WorldWideScience

Sample records for sample locality maps

  1. Local activation time sampling density for atrial tachycardia contact mapping: how much is enough?

    Science.gov (United States)

    Williams, Steven E; Harrison, James L; Chubb, Henry; Whitaker, John; Kiedrowicz, Radek; Rinaldi, Christopher A; Cooklin, Michael; Wright, Matthew; Niederer, Steven; O'Neill, Mark D

    2018-02-01

    Local activation time (LAT) mapping forms the cornerstone of atrial tachycardia diagnosis. Although anatomic and positional accuracy of electroanatomic mapping (EAM) systems have been validated, the effect of electrode sampling density on LAT map reconstruction is not known. Here, we study the effect of chamber geometry and activation complexity on optimal LAT sampling density using a combined in silico and in vivo approach. In vivo 21 atrial tachycardia maps were studied in three groups: (1) focal activation, (2) macro-re-entry, and (3) localized re-entry. In silico activation was simulated on a 4×4cm atrial monolayer, sampled randomly at 0.25-10 points/cm2 and used to re-interpolate LAT maps. Activation patterns were studied in the geometrically simple porcine right atrium (RA) and complex human left atrium (LA). Activation complexity was introduced into the porcine RA by incomplete inter-caval linear ablation. In all cases, optimal sampling density was defined as the highest density resulting in minimal further error reduction in the re-interpolated maps. Optimal sampling densities for LA tachycardias were 0.67 ± 0.17 points/cm2 (focal activation), 1.05 ± 0.32 points/cm2 (macro-re-entry) and 1.23 ± 0.26 points/cm2 (localized re-entry), P = 0.0031. Increasing activation complexity was associated with increased optimal sampling density both in silico (focal activation 1.09 ± 0.14 points/cm2; re-entry 1.44 ± 0.49 points/cm2; spiral-wave 1.50 ± 0.34 points/cm2, P density (0.61 ± 0.22 points/cm2 vs. 1.0 ± 0.34 points/cm2, P = 0.0015). Optimal sampling densities can be identified to maximize diagnostic yield of LAT maps. Greater sampling density is required to correctly reveal complex activation and represent activation across complex geometries. Overall, the optimal sampling density for LAT map interpolation defined in this study was ∼1.0-1.5 points/cm2. Published on behalf of the European Society of

  2. Approach of simultaneous localization and mapping based on local maps for robot

    Institute of Scientific and Technical Information of China (English)

    CHEN Bai-fan; CAI Zi-xing; HU De-wen

    2006-01-01

    An extended Kalman filter approach of simultaneous localization and mapping(SLAM) was proposed based on local maps.A local frame of reference was established periodically at the position of the robot, and then the observations of the robot and landmarks were fused into the global frame of reference. Because of the independence of the local map, the approach does not cumulate the estimate and calculation errors which are produced by SLAM using Kalman filter directly. At the same time, it reduces the computational complexity. This method is proven correct and feasible in simulation experiments.

  3. Recovering Sample Diversity in Rao-Blackwellized Particle Filters for Simultaneous Localization and Mapping

    National Research Council Canada - National Science Library

    Anderson, Andrew D

    2006-01-01

    ...) in simultaneous localization and mapping (SLAM) situations that arises when precise feature measurements yield a limited perceptual distribution relative to a motion-based proposal distribution...

  4. Geographical affinities of the HapMap samples.

    Directory of Open Access Journals (Sweden)

    Miao He

    Full Text Available The HapMap samples were collected for medical-genetic studies, but are also widely used in population-genetic and evolutionary investigations. Yet the ascertainment of the samples differs from most population-genetic studies which collect individuals who live in the same local region as their ancestors. What effects could this non-standard ascertainment have on the interpretation of HapMap results?We compared the HapMap samples with more conventionally-ascertained samples used in population- and forensic-genetic studies, including the HGDP-CEPH panel, making use of published genome-wide autosomal SNP data and Y-STR haplotypes, as well as producing new Y-STR data. We found that the HapMap samples were representative of their broad geographical regions of ancestry according to all tests applied. The YRI and JPT were indistinguishable from independent samples of Yoruba and Japanese in all ways investigated. However, both the CHB and the CEU were distinguishable from all other HGDP-CEPH populations with autosomal markers, and both showed Y-STR similarities to unusually large numbers of populations, perhaps reflecting their admixed origins.The CHB and JPT are readily distinguished from one another with both autosomal and Y-chromosomal markers, and results obtained after combining them into a single sample should be interpreted with caution. The CEU are better described as being of Western European ancestry than of Northern European ancestry as often reported. Both the CHB and CEU show subtle but detectable signs of admixture. Thus the YRI and JPT samples are well-suited to standard population-genetic studies, but the CHB and CEU less so.

  5. USING M DWARF SPECTRA TO MAP EXTINCTION IN THE LOCAL GALAXY

    International Nuclear Information System (INIS)

    Jones, David O.; West, Andrew A.; Foster, Jonathan B.

    2011-01-01

    We use spectra of more than 56,000 M dwarfs from the Sloan Digital Sky Survey (SDSS) to create a high-latitude extinction map of the local Galaxy. Our technique compares spectra from the stars in the SDSS Data Release 7 M dwarf sample in low-extinction lines of sight, as determined by Schlegel et al., to other SDSS M dwarf spectra in order to derive improved distance estimates and accurate line-of-sight extinctions. Unlike most previous studies, which have used a two-color method to determine extinction, we fit extinction curves to fluxes across the spectral range from 5700 to 9200 A for every star in our sample. Our result is an A V map that extends from a few tens of pc to approximately 2 kpc away from the Sun. We also use a similar technique to create a map of R V values within approximately 1 kpc of the Sun and find that they are consistent with the widely accepted diffuse interstellar medium value of 3.1. Using our extinction data, we derive a dust scale height for the local Galaxy of 119 ± 15 pc and find evidence for a local dust cavity.

  6. Effective absorption correction for energy dispersive X-ray mapping in a scanning transmission electron microscope: analysing the local indium distribution in rough samples of InGaN alloy layers.

    Science.gov (United States)

    Wang, X; Chauvat, M-P; Ruterana, P; Walther, T

    2017-12-01

    We have applied our previous method of self-consistent k*-factors for absorption correction in energy-dispersive X-ray spectroscopy to quantify the indium content in X-ray maps of thick compound InGaN layers. The method allows us to quantify the indium concentration without measuring the sample thickness, density or beam current, and works even if there is a drastic local thickness change due to sample roughness or preferential thinning. The method is shown to select, point-by-point in a two-dimensional spectrum image or map, the k*-factor from the local Ga K/L intensity ratio that is most appropriate for the corresponding sample geometry, demonstrating it is not the sample thickness measured along the electron beam direction but the optical path length the X-rays have to travel through the sample that is relevant for the absorption correction. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

  7. Mapping the results of local statistics: Using geographically weighted regression

    Directory of Open Access Journals (Sweden)

    Stephen A. Matthews

    2012-03-01

    Full Text Available BACKGROUND The application of geographically weighted regression (GWR - a local spatial statistical technique used to test for spatial nonstationarity - has grown rapidly in the social, health, and demographic sciences. GWR is a useful exploratory analytical tool that generates a set of location-specific parameter estimates which can be mapped and analysed to provide information on spatial nonstationarity in the relationships between predictors and the outcome variable. OBJECTIVE A major challenge to users of GWR methods is how best to present and synthesize the large number of mappable results, specifically the local parameter parameter estimates and local t-values, generated from local GWR models. We offer an elegant solution. METHODS This paper introduces a mapping technique to simultaneously display local parameter estimates and local t-values on one map based on the use of data selection and transparency techniques. We integrate GWR software and GIS software package (ArcGIS and adapt earlier work in cartography on bivariate mapping. We compare traditional mapping strategies (i.e., side-by-side comparison and isoline overlay maps with our method using an illustration focusing on US county infant mortality data. CONCLUSIONS The resultant map design is more elegant than methods used to date. This type of map presentation can facilitate the exploration and interpretation of nonstationarity, focusing map reader attention on the areas of primary interest.

  8. Local adaptive tone mapping for video enhancement

    Science.gov (United States)

    Lachine, Vladimir; Dai, Min (.

    2015-03-01

    As new technologies like High Dynamic Range cameras, AMOLED and high resolution displays emerge on consumer electronics market, it becomes very important to deliver the best picture quality for mobile devices. Tone Mapping (TM) is a popular technique to enhance visual quality. However, the traditional implementation of Tone Mapping procedure is limited by pixel's value to value mapping, and the performance is restricted in terms of local sharpness and colorfulness. To overcome the drawbacks of traditional TM, we propose a spatial-frequency based framework in this paper. In the proposed solution, intensity component of an input video/image signal is split on low pass filtered (LPF) and high pass filtered (HPF) bands. Tone Mapping (TM) function is applied to LPF band to improve the global contrast/brightness, and HPF band is added back afterwards to keep the local contrast. The HPF band may be adjusted by a coring function to avoid noise boosting and signal overshooting. Colorfulness of an original image may be preserved or enhanced by chroma components correction by means of saturation function. Localized content adaptation is further improved by dividing an image to a set of non-overlapped regions and modifying each region individually. The suggested framework allows users to implement a wide range of tone mapping applications with perceptional local sharpness and colorfulness preserved or enhanced. Corresponding hardware circuit may be integrated in camera, video or display pipeline with minimal hardware budget

  9. Stochastic Wheel-Slip Compensation Based Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    SIDHARTHAN, R. K.

    2016-05-01

    Full Text Available Wheel slip compensation is vital for building accurate and reliable dead reckoning based robot localization and mapping algorithms. This investigation presents stochastic slip compensation scheme for robot localization and mapping. Main idea of the slip compensation technique is to use wheel-slip data obtained from experiments to model the variations in slip velocity as Gaussian distributions. This leads to a family of models that are switched depending on the input command. To obtain the wheel-slip measurements, experiments are conducted on a wheeled mobile robot and the measurements thus obtained are used to build the Gaussian models. Then the localization and mapping algorithm is tested on an experimental terrain and a new metric called the map spread factor is used to evaluate the ability of the slip compensation technique. Our results clearly indicate that the proposed methodology improves the accuracy by 72.55% for rotation and 66.67% for translation motion as against an uncompensated mapping system. The proposed compensation technique eliminates the need for extro receptive sensors for slip compensation, complex feature extraction and association algorithms. As a result, we obtain a simple slip compensation scheme for localization and mapping.

  10. Sampling for validation of digital soil maps

    NARCIS (Netherlands)

    Brus, D.J.; Kempen, B.; Heuvelink, G.B.M.

    2011-01-01

    The increase in digital soil mapping around the world means that appropriate and efficient sampling strategies are needed for validation. Data used for calibrating a digital soil mapping model typically are non-random samples. In such a case we recommend collection of additional independent data and

  11. Mapping local anisotropy axis for scattering media using backscattering Mueller matrix imaging

    Science.gov (United States)

    He, Honghui; Sun, Minghao; Zeng, Nan; Du, E.; Guo, Yihong; He, Yonghong; Ma, Hui

    2014-03-01

    Mueller matrix imaging techniques can be used to detect the micro-structure variations of superficial biological tissues, including the sizes and shapes of cells, the structures in cells, and the densities of the organelles. Many tissues contain anisotropic fibrous micro-structures, such as collagen fibers, elastin fibers, and muscle fibers. Changes of these fibrous structures are potentially good indicators for some pathological variations. In this paper, we propose a quantitative analysis technique based on Mueller matrix for mapping local anisotropy axis of scattering media. By conducting both experiments on silk sample and Monte Carlo simulation based on the sphere-cylinder scattering model (SCSM), we extract anisotropy axis parameters from different backscattering Mueller matrix elements. Moreover, we testify the possible applications of these parameters for biological tissues. The preliminary experimental results of human cancerous samples show that, these parameters are capable to map the local axis of fibers. Since many pathological changes including early stage cancers affect the well aligned structures for tissues, the experimental results indicate that these parameters can be used as potential tools in clinical applications for biomedical diagnosis purposes.

  12. Harmonic Riemannian Maps on Locally Conformal Kaehler Manifolds

    Indian Academy of Sciences (India)

    We study harmonic Riemannian maps on locally conformal Kaehler manifolds ( l c K manifolds). We show that if a Riemannian holomorphic map between l c K manifolds is harmonic, then the Lee vector field of the domain belongs to the kernel of the Riemannian map under a condition. When the domain is Kaehler, we ...

  13. A Probabilistic Feature Map-Based Localization System Using a Monocular Camera

    Directory of Open Access Journals (Sweden)

    Hyungjin Kim

    2015-08-01

    Full Text Available Image-based localization is one of the most widely researched localization techniques in the robotics and computer vision communities. As enormous image data sets are provided through the Internet, many studies on estimating a location with a pre-built image-based 3D map have been conducted. Most research groups use numerous image data sets that contain sufficient features. In contrast, this paper focuses on image-based localization in the case of insufficient images and features. A more accurate localization method is proposed based on a probabilistic map using 3D-to-2D matching correspondences between a map and a query image. The probabilistic feature map is generated in advance by probabilistic modeling of the sensor system as well as the uncertainties of camera poses. Using the conventional PnP algorithm, an initial camera pose is estimated on the probabilistic feature map. The proposed algorithm is optimized from the initial pose by minimizing Mahalanobis distance errors between features from the query image and the map to improve accuracy. To verify that the localization accuracy is improved, the proposed algorithm is compared with the conventional algorithm in a simulation and realenvironments

  14. A Probabilistic Feature Map-Based Localization System Using a Monocular Camera.

    Science.gov (United States)

    Kim, Hyungjin; Lee, Donghwa; Oh, Taekjun; Choi, Hyun-Taek; Myung, Hyun

    2015-08-31

    Image-based localization is one of the most widely researched localization techniques in the robotics and computer vision communities. As enormous image data sets are provided through the Internet, many studies on estimating a location with a pre-built image-based 3D map have been conducted. Most research groups use numerous image data sets that contain sufficient features. In contrast, this paper focuses on image-based localization in the case of insufficient images and features. A more accurate localization method is proposed based on a probabilistic map using 3D-to-2D matching correspondences between a map and a query image. The probabilistic feature map is generated in advance by probabilistic modeling of the sensor system as well as the uncertainties of camera poses. Using the conventional PnP algorithm, an initial camera pose is estimated on the probabilistic feature map. The proposed algorithm is optimized from the initial pose by minimizing Mahalanobis distance errors between features from the query image and the map to improve accuracy. To verify that the localization accuracy is improved, the proposed algorithm is compared with the conventional algorithm in a simulation and realenvironments.

  15. Analytical data and sample locality map for aqua-regia leachates of stream sediments analyzed by ICP, and emission spectrographic and ICP results for many NURE stream sediments from the Killik River Quadrangle, Alaska

    International Nuclear Information System (INIS)

    Motooka, J.M.; Adrian, B.M.; Church, S.E.; McDougal, C.M.; Fife, J.B.

    1989-01-01

    A U.S. Geological Survey report is presented giving analytical data and sample locality map for aqua-regia leachates of stream sediments analyzed by ICP, and emission spectrographic and ICP results for many NURE stream sediments from the Killik River Quadrangle, Alaska

  16. Functional Maps of Neocortical Local Circuitry

    Science.gov (United States)

    Thomson, Alex M.; Lamy, Christophe

    2007-01-01

    This review aims to summarize data obtained with different techniques to provide a functional map of the local circuit connections made by neocortical neurones, a reference for those interested in cortical circuitry and the numerical information required by those wishing to model the circuit. A brief description of the main techniques used to study circuitry is followed by outline descriptions of the major classes of neocortical excitatory and inhibitory neurones and the connections that each layer makes with other cortical and subcortical regions. Maps summarizing the projection patterns of each class of neurone within the local circuit and tables of the properties of these local circuit connections are provided. This review relies primarily on anatomical studies that have identified the classes of neurones and their local and long distance connections and on paired intracellular and whole-cell recordings which have documented the properties of the connections between them. A large number of different types of synaptic connections have been described, but for some there are only a few published examples and for others the details that can only be obtained with paired recordings and dye-filling are lacking. A further complication is provided by the range of species, technical approaches and age groups used in these studies. Wherever possible the range of available data are summarised and compared. To fill some of the more obvious gaps for the less well-documented cases, data obtained with other methods are also summarized. PMID:18982117

  17. Prediction of CT Substitutes from MR Images Based on Local Diffeomorphic Mapping for Brain PET Attenuation Correction.

    Science.gov (United States)

    Wu, Yao; Yang, Wei; Lu, Lijun; Lu, Zhentai; Zhong, Liming; Huang, Meiyan; Feng, Yanqiu; Feng, Qianjin; Chen, Wufan

    2016-10-01

    Attenuation correction is important for PET reconstruction. In PET/MR, MR intensities are not directly related to attenuation coefficients that are needed in PET imaging. The attenuation coefficient map can be derived from CT images. Therefore, prediction of CT substitutes from MR images is desired for attenuation correction in PET/MR. This study presents a patch-based method for CT prediction from MR images, generating attenuation maps for PET reconstruction. Because no global relation exists between MR and CT intensities, we propose local diffeomorphic mapping (LDM) for CT prediction. In LDM, we assume that MR and CT patches are located on 2 nonlinear manifolds, and the mapping from the MR manifold to the CT manifold approximates a diffeomorphism under a local constraint. Locality is important in LDM and is constrained by the following techniques. The first is local dictionary construction, wherein, for each patch in the testing MR image, a local search window is used to extract patches from training MR/CT pairs to construct MR and CT dictionaries. The k-nearest neighbors and an outlier detection strategy are then used to constrain the locality in MR and CT dictionaries. Second is local linear representation, wherein, local anchor embedding is used to solve MR dictionary coefficients when representing the MR testing sample. Under these local constraints, dictionary coefficients are linearly transferred from the MR manifold to the CT manifold and used to combine CT training samples to generate CT predictions. Our dataset contains 13 healthy subjects, each with T1- and T2-weighted MR and CT brain images. This method provides CT predictions with a mean absolute error of 110.1 Hounsfield units, Pearson linear correlation of 0.82, peak signal-to-noise ratio of 24.81 dB, and Dice in bone regions of 0.84 as compared with real CTs. CT substitute-based PET reconstruction has a regression slope of 1.0084 and R 2 of 0.9903 compared with real CT-based PET. In this method, no

  18. A short note on nearly perfect maps of locales | Razafindrakoto ...

    African Journals Online (AJOL)

    We characterise compact locales in terms of nearly perfect maps. We show in particular that these maps are the natural pointfree version of Bourbaki's proper maps - when defined via any ultrafillter - and that they extend Herrlich's notion of nearly closed sublocales [10]. Mathematics Subject Classication (2010): 06A15, ...

  19. Spatial Mapping of Organic Carbon in Returned Samples from Mars

    Science.gov (United States)

    Siljeström, S.; Fornaro, T.; Greenwalt, D.; Steele, A.

    2018-04-01

    To map organic material spatially to minerals present in the sample will be essential for the understanding of the origin of any organics in returned samples from Mars. It will be shown how ToF-SIMS may be used to map organics in samples from Mars.

  20. Simultaneous Localization and Mapping for Satellite Rendezvous and Proximity Operations

    Data.gov (United States)

    National Aeronautics and Space Administration — Simultaneous Localization and Mapping (SLAM) attempts to estimate a vehicle’s position and orientation (localization) and the location of an initially unknown number...

  1. Integrated multi-sensor fusion for mapping and localization in outdoor environments for mobile robots

    Science.gov (United States)

    Emter, Thomas; Petereit, Janko

    2014-05-01

    An integrated multi-sensor fusion framework for localization and mapping for autonomous navigation in unstructured outdoor environments based on extended Kalman filters (EKF) is presented. The sensors for localization include an inertial measurement unit, a GPS, a fiber optic gyroscope, and wheel odometry. Additionally a 3D LIDAR is used for simultaneous localization and mapping (SLAM). A 3D map is built while concurrently a localization in a so far established 2D map is estimated with the current scan of the LIDAR. Despite of longer run-time of the SLAM algorithm compared to the EKF update, a high update rate is still guaranteed by sophisticatedly joining and synchronizing two parallel localization estimators.

  2. An Odometry-free Approach for Simultaneous Localization and Online Hybrid Map Building

    Directory of Open Access Journals (Sweden)

    Wei Hong Chin

    2016-11-01

    Full Text Available In this paper, a new approach is proposed for mobile robot localization and hybrid map building simultaneously without using any odometry hardware system. The proposed method termed as Genetic Bayesian ARAM which comprises two main components: 1 Steady state genetic algorithm (SSGA for self-localization and occupancy grid map building; 2 Bayesian Adaptive Resonance Associative Memory (ARAM for online topological map building. The model of the explored environment is formed as a hybrid representation, both topological and grid-based, and it is incrementally constructed during the exploration process. During occupancy map building, robot estimated self-position is updated by SSGA. At the same time, robot estimated self position is transmit to Bayesian ARAM for topological map building and localization. The effectiveness of our proposed approach is validated by a number of standardized benchmark datasets and real experimental results carried on mobile robot. Benchmark datasets are used to verify the proposed method capable of generating topological map in different environment conditions. Real robot experiment is to verify the proposed method can be implemented in real world.

  3. CellMap visualizes protein-protein interactions and subcellular localization

    Science.gov (United States)

    Dallago, Christian; Goldberg, Tatyana; Andrade-Navarro, Miguel Angel; Alanis-Lobato, Gregorio; Rost, Burkhard

    2018-01-01

    Many tools visualize protein-protein interaction (PPI) networks. The tool introduced here, CellMap, adds one crucial novelty by visualizing PPI networks in the context of subcellular localization, i.e. the location in the cell or cellular component in which a PPI happens. Users can upload images of cells and define areas of interest against which PPIs for selected proteins are displayed (by default on a cartoon of a cell). Annotations of localization are provided by the user or through our in-house database. The visualizer and server are written in JavaScript, making CellMap easy to customize and to extend by researchers and developers. PMID:29497493

  4. A critique of current developments in simultaneous localization and mapping

    Directory of Open Access Journals (Sweden)

    Shoudong Huang

    2016-10-01

    Full Text Available The number of research publications dealing with the simultaneous localization and mapping problem has grown significantly over the past 15 years. Many fundamental and practical aspects of simultaneous localization and mapping have been addressed, and some efficient algorithms and practical solutions have been demonstrated. The aim of this paper is to provide a critical review of current theoretical understanding of the fundamental properties of the SLAM problem, such as observability, convergence, achievable accuracy and consistency. Recent research outcomes associated with these topics are briefly discussed together with potential future research directions.

  5. Automatic traveltime picking using local time-frequency maps

    KAUST Repository

    Saragiotis, Christos; Alkhalifah, Tariq Ali; Fomel, Sergey B.

    2011-01-01

    The arrival times of distinct and sufficiently concentrated signals can be computed using Fourier transforms. In real seis- mograms, however, signals are far from distinct. We use local time-frequency maps of the seismograms and its frequency

  6. Single Image Super-Resolution Using Global Regression Based on Multiple Local Linear Mappings.

    Science.gov (United States)

    Choi, Jae-Seok; Kim, Munchurl

    2017-03-01

    Super-resolution (SR) has become more vital, because of its capability to generate high-quality ultra-high definition (UHD) high-resolution (HR) images from low-resolution (LR) input images. Conventional SR methods entail high computational complexity, which makes them difficult to be implemented for up-scaling of full-high-definition input images into UHD-resolution images. Nevertheless, our previous super-interpolation (SI) method showed a good compromise between Peak-Signal-to-Noise Ratio (PSNR) performances and computational complexity. However, since SI only utilizes simple linear mappings, it may fail to precisely reconstruct HR patches with complex texture. In this paper, we present a novel SR method, which inherits the large-to-small patch conversion scheme from SI but uses global regression based on local linear mappings (GLM). Thus, our new SR method is called GLM-SI. In GLM-SI, each LR input patch is divided into 25 overlapped subpatches. Next, based on the local properties of these subpatches, 25 different local linear mappings are applied to the current LR input patch to generate 25 HR patch candidates, which are then regressed into one final HR patch using a global regressor. The local linear mappings are learned cluster-wise in our off-line training phase. The main contribution of this paper is as follows: Previously, linear-mapping-based conventional SR methods, including SI only used one simple yet coarse linear mapping to each patch to reconstruct its HR version. On the contrary, for each LR input patch, our GLM-SI is the first to apply a combination of multiple local linear mappings, where each local linear mapping is found according to local properties of the current LR patch. Therefore, it can better approximate nonlinear LR-to-HR mappings for HR patches with complex texture. Experiment results show that the proposed GLM-SI method outperforms most of the state-of-the-art methods, and shows comparable PSNR performance with much lower

  7. Local thermodynamic mapping for effective liquid density-functional theory

    Science.gov (United States)

    Kyrlidis, Agathagelos; Brown, Robert A.

    1992-01-01

    The structural-mapping approximation introduced by Lutsko and Baus (1990) in the generalized effective-liquid approximation is extended to include a local thermodynamic mapping based on a spatially dependent effective density for approximating the solid phase in terms of the uniform liquid. This latter approximation, called the local generalized effective-liquid approximation (LGELA) yields excellent predictions for the free energy of hard-sphere solids and for the conditions of coexistence of a hard-sphere fcc solid with a liquid. Moreover, the predicted free energy remains single valued for calculations with more loosely packed crystalline structures, such as the diamond lattice. The spatial dependence of the weighted density makes the LGELA useful in the study of inhomogeneous solids.

  8. Assessing local knowledge use in agroforestry management with cognitive maps.

    Science.gov (United States)

    Isaac, Marney E; Dawoe, Evans; Sieciechowicz, Krystyna

    2009-06-01

    Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production. In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices, (2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 +/- 3 variables and 19 +/- 3 links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment, and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation, thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks and that cognitive mapping provides a tool-based approach to advance such a management support system.

  9. Assessing Local Knowledge Use in Agroforestry Management with Cognitive Maps

    Science.gov (United States)

    Isaac, Marney E.; Dawoe, Evans; Sieciechowicz, Krystyna

    2009-06-01

    Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production. In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices, (2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 ± 3 variables and 19 ± 3 links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment, and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation, thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks and that cognitive mapping provides a tool-based approach to advance such a management support system.

  10. Keyframes Global Map Establishing Method for Robot Localization through Content-Based Image Matching

    Directory of Open Access Journals (Sweden)

    Tianyang Cao

    2017-01-01

    Full Text Available Self-localization and mapping are important for indoor mobile robot. We report a robust algorithm for map building and subsequent localization especially suited for indoor floor-cleaning robots. Common methods, for example, SLAM, can easily be kidnapped by colliding or disturbed by similar objects. Therefore, keyframes global map establishing method for robot localization in multiple rooms and corridors is needed. Content-based image matching is the core of this method. It is designed for the situation, by establishing keyframes containing both floor and distorted wall images. Image distortion, caused by robot view angle and movement, is analyzed and deduced. And an image matching solution is presented, consisting of extraction of overlap regions of keyframes extraction and overlap region rebuild through subblocks matching. For improving accuracy, ceiling points detecting and mismatching subblocks checking methods are incorporated. This matching method can process environment video effectively. In experiments, less than 5% frames are extracted as keyframes to build global map, which have large space distance and overlap each other. Through this method, robot can localize itself by matching its real-time vision frames with our keyframes map. Even with many similar objects/background in the environment or kidnapping robot, robot localization is achieved with position RMSE <0.5 m.

  11. FAST Mapping of Diffuse HI Gas in the Local Universe

    Science.gov (United States)

    Zhu, M.; Pisano, D. J.; Ai, M.; Jiao, Q.

    2016-02-01

    We propose to use the Five hundred meter Aperture Spherical radio Telescope (FAST) to map the diffuse intergalactic HI gas in the local universe at column densities of NHI=1018 cm-2 and below. The major science goal is to study gas accretion during galaxy evolution, and trace cosmic web features in the local universe. We disuss the technical feasibilty of such a deep survey, and have conducted test observations with the Arecibo 305 m telescope. Our preliminary results shows that, with about a few thousand hours of observing time, FAST will be able to map several hundred square degree regions at 1 σ of NHI=2×1017 cm-2 level out to a distance of 5-10 Mpc, and with a volume 1000 larger than that of the Local Group.

  12. MAP Fault Localization Based on Wide Area Synchronous Phasor Measurement Information

    Science.gov (United States)

    Zhang, Yagang; Wang, Zengping

    2015-02-01

    In the research of complicated electrical engineering, the emergence of phasor measurement units (PMU) is a landmark event. The establishment and application of wide area measurement system (WAMS) in power system has made widespread and profound influence on the safe and stable operation of complicated power system. In this paper, taking full advantage of wide area synchronous phasor measurement information provided by PMUs, we have carried out precise fault localization based on the principles of maximum posteriori probability (MAP). Large numbers of simulation experiments have confirmed that the results of MAP fault localization are accurate and reliable. Even if there are interferences from white Gaussian stochastic noise, the results from MAP classification are also identical to the actual real situation.

  13. How to generate a sound-localization map in fish

    Science.gov (United States)

    van Hemmen, J. Leo

    2015-03-01

    How sound localization is represented in the fish brain is a research field largely unbiased by theoretical analysis and computational modeling. Yet, there is experimental evidence that the axes of particle acceleration due to underwater sound are represented through a map in the midbrain of fish, e.g., in the torus semicircularis of the rainbow trout (Wubbels et al. 1997). How does such a map arise? Fish perceive pressure gradients by their three otolithic organs, each of which comprises a dense, calcareous, stone that is bathed in endolymph and attached to a sensory epithelium. In rainbow trout, the sensory epithelia of left and right utricle lie in the horizontal plane and consist of hair cells with equally distributed preferred orientations. We model the neuronal response of this system on the basis of Schuijf's vector detection hypothesis (Schuijf et al. 1975) and introduce a temporal spike code of sound direction, where optimality of hair cell orientation θj with respect to the acceleration direction θs is mapped onto spike phases via a von-Mises distribution. By learning to tune in to the earliest synchronized activity, nerve cells in the midbrain generate a map under the supervision of a locally excitatory, yet globally inhibitory visual teacher. Work done in collaboration with Daniel Begovic. Partially supported by BCCN - Munich.

  14. Localization and Mapping Using a Non-Central Catadioptric Camera System

    Science.gov (United States)

    Khurana, M.; Armenakis, C.

    2018-05-01

    This work details the development of an indoor navigation and mapping system using a non-central catadioptric omnidirectional camera and its implementation for mobile applications. Omnidirectional catadioptric cameras find their use in navigation and mapping of robotic platforms, owing to their wide field of view. Having a wider field of view, or rather a potential 360° field of view, allows the system to "see and move" more freely in the navigation space. A catadioptric camera system is a low cost system which consists of a mirror and a camera. Any perspective camera can be used. A platform was constructed in order to combine the mirror and a camera to build a catadioptric system. A calibration method was developed in order to obtain the relative position and orientation between the two components so that they can be considered as one monolithic system. The mathematical model for localizing the system was determined using conditions based on the reflective properties of the mirror. The obtained platform positions were then used to map the environment using epipolar geometry. Experiments were performed to test the mathematical models and the achieved location and mapping accuracies of the system. An iterative process of positioning and mapping was applied to determine object coordinates of an indoor environment while navigating the mobile platform. Camera localization and 3D coordinates of object points obtained decimetre level accuracies.

  15. Simultaneous Localization and Mapping for Planetary Surface Mobility, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC and Carnegie Mellon University have formed a partnership to commercially develop localization and mapping technologies for planetary rovers....

  16. Testing of Alignment Parameters for Ancient Samples: Evaluating and Optimizing Mapping Parameters for Ancient Samples Using the TAPAS Tool

    Directory of Open Access Journals (Sweden)

    Ulrike H. Taron

    2018-03-01

    Full Text Available High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present ‘TAPAS’, (Testing of Alignment Parameters for Ancient Samples, a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang (Prionodon linsang, for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material.

  17. REVERBERATION MAPPING MEASUREMENTS OF BLACK HOLE MASSES IN SIX LOCAL SEYFERT GALAXIES

    International Nuclear Information System (INIS)

    Denney, K. D.; Peterson, B. M.; Pogge, R. W.; Atlee, D. W.; Bentz, M. C.; Bird, J. C.; Comins, M. L.; Dietrich, M.; Eastman, J. D.; Adair, A.; Au-Yong, K.; Chisholm, E.; Ewald, S.; Ferbey, S.; Jackson, K.; Brokofsky, D. J.; Gaskell, C. M.; Hedrick, C. H.; Doroshenko, V. T.; Efimov, Y. S.

    2010-01-01

    We present the final results from a high sampling rate, multi-month, spectrophotometric reverberation mapping campaign undertaken to obtain either new or improved Hβ reverberation lag measurements for several relatively low-luminosity active galactic nuclei (AGNs). We have reliably measured the time delay between variations in the continuum and Hβ emission line in six local Seyfert 1 galaxies. These measurements are used to calculate the mass of the supermassive black hole at the center of each of these AGNs. We place our results in context to the most current calibration of the broad-line region (BLR) R BLR -L relationship, where our results remove outliers and reduce the scatter at the low-luminosity end of this relationship. We also present velocity-resolved Hβ time-delay measurements for our complete sample, though the clearest velocity-resolved kinematic signatures have already been published.

  18. Demonstration of inaccuracy of QTL mapping due to sampling error€

    African Journals Online (AJOL)

    Bertrand Collard

    2012-06-12

    Jun 12, 2012 ... finding in simple terms so that findings and implications can be easily ... While sampling from the true populations for n = 94 and n =190, individual mapping .... Overview of QTL mapping experimental design. Four true ...

  19. Small-angle X-ray scattering tensor tomography: model of the three-dimensional reciprocal-space map, reconstruction algorithm and angular sampling requirements.

    Science.gov (United States)

    Liebi, Marianne; Georgiadis, Marios; Kohlbrecher, Joachim; Holler, Mirko; Raabe, Jörg; Usov, Ivan; Menzel, Andreas; Schneider, Philipp; Bunk, Oliver; Guizar-Sicairos, Manuel

    2018-01-01

    Small-angle X-ray scattering tensor tomography, which allows reconstruction of the local three-dimensional reciprocal-space map within a three-dimensional sample as introduced by Liebi et al. [Nature (2015), 527, 349-352], is described in more detail with regard to the mathematical framework and the optimization algorithm. For the case of trabecular bone samples from vertebrae it is shown that the model of the three-dimensional reciprocal-space map using spherical harmonics can adequately describe the measured data. The method enables the determination of nanostructure orientation and degree of orientation as demonstrated previously in a single momentum transfer q range. This article presents a reconstruction of the complete reciprocal-space map for the case of bone over extended ranges of q. In addition, it is shown that uniform angular sampling and advanced regularization strategies help to reduce the amount of data required.

  20. Urban local climate zone mapping and apply in urban environment study

    Science.gov (United States)

    He, Shan; Zhang, Yunwei; Zhang, Jili

    2018-02-01

    The city’s local climate zone (LCZ) was considered to be a powerful tool for urban climate mapping. But for cities in different countries and regions, the LCZ division methods and results were different, thus targeted researches should be performed. In the current work, a LCZ mapping method was proposed, which is convenient in operation and city planning oriented. In this proposed method, the local climate zoning types were adjusted firstly, according to the characteristics of Chinese city, that more tall buildings and high density. Then the classification method proposed by WUDAPT based on remote sensing data was performed on Xi’an city, as an example, for LCZ mapping. Combined with the city road network, a reasonable expression of the dividing results was provided, to adapt to the characteristics in city planning that land parcels are usually recognized as the basic unit. The proposed method was validated against the actual land use and construction data that surveyed in Xi’an, with results indicating the feasibility of the proposed method for urban LCZ mapping in China.

  1. Localizing New Pulsars with Intensity Mapping

    Science.gov (United States)

    Swiggum, Joe; Gentile, Peter

    2018-01-01

    Although low-frequency, single dish pulsar surveys provide an efficient means of searching large regions of sky quickly, the localization of new discoveries is poor. For example, discoveries from 350 MHz surveys using the Green Bank Telescope (GBT) have position uncertainties up to the FWHM of the telescope's "beam" on the sky, over half a degree! Before finding a coherent timing solution (requires 8-12 months of dedicated timing observations) a "gridding" method is usually employed to improve localization of new pulsars, whereby a grid of higher frequency beam positions is used to tile the initial error region. This method often requires over an hour of observing time to achieve arcminute-precision localization (provided the pulsar is detectable at higher frequencies).Here, we describe another method that uses the same observing frequency as the discovery observation and scans over Right Ascension and Declination directions around the nominal position. A Gaussian beam model is fit to folded pulse profile intensities as a function of time/position to provide improved localization. Using five test cases, we show that intensity mapping localization at 350 MHz with the GBT yields pulsar positions to 1 arcminute precision, facilitating high-frequency follow-up and higher significance detections for future pulsar timing. This method is also well suited to be directly implemented in future low-frequency drift scan pulsar surveys (e.g. with the Five hundred meter Aperture Spherical Telescope; FAST).

  2. Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization

    National Research Council Canada - National Science Library

    Owens, Kevin L

    2005-01-01

    This research effort explores and develops a real-time sonar-based robot mapping and localization algorithm that provides pose correction within the context of a singe room, to be combined with pre...

  3. Fishing site mapping using local knowledge provides accurate and ...

    African Journals Online (AJOL)

    Accurate fishing ground maps are necessary for fisheries monitoring. In Velondriake locally managed marine area (LMMA) we observed that the nomenclature of shared fishing sites (FS) is villages dependent. Additionally, the level of illiteracy makes data collection more complicated, leading to data collectors improvising ...

  4. Mapping of marine benthic invertebrates in the Oslofjord and the Skagerrak: sampling data of museum collections from 1950-1955 and from recent investigations

    Directory of Open Access Journals (Sweden)

    Eivind Oug

    2015-12-01

    Full Text Available Data from large sampling programmes for the mapping of marine invertebrates in the Oslofjord, Norway, and the Skagerrak, spanning more than six decades, are compiled and digitized to provide easy access in modern data repositories. Two sampling programmes undertaken in the period 1950–55 are still the most extensive mapping of marine benthic fauna in the area. Information from a total of more than 900 localities, or sampling events, covering all benthic habitats in the Oslofjord and coastal waters to Kvitsøy in Rogaland county, have been carefully digitized from field notes, original sea charts, and primary observations from sample handling in the field. Geographical coordinates referred to WGS84 chart datum have been fixed with a general accuracy of 20 m in the Oslofjord and 100–250 m in coastal areas, based on precise map sketches with cross-bearings to land objects and chart annotations. Most samples were collected using triangular, Agassiz and lightweight dredges. The collected material has been deposited in the collections of the Natural History Museum, University of Oslo. Two recent projects, ‘Polyskag’ and ‘Bioskag’ (2006–2014, are briefly described. The projects focused on the diversity of marine bristle worms (Polychaeta, inter alia providing material for molecular genetic analyses. Type localities for early described species and generally understudied biotopes were visited. The data from the 1950s, together with recent studies, constitute a considerable resource for studies of biodiversity, facilitated through the sharing of species records from the museum collections in modern data repositories. The accurate positioning of sampling localities in the 1950s is of particular value for documenting species distributions over long time spans, thus providing a reference base for studying present and future species changes and assessing the effects of human influence and environmental changes in the Oslofjord and the Skagerrak.

  5. Visual-based simultaneous localization and mapping and global positioning system correction for geo-localization of a mobile robot

    International Nuclear Information System (INIS)

    Berrabah, Sid Ahmed; Baudoin, Yvan; Sahli, Hichem

    2011-01-01

    This paper introduces an approach combining visual-based simultaneous localization and mapping (V-SLAM) and global positioning system (GPS) correction for accurate multi-sensor localization of an outdoor mobile robot in geo-referenced maps. The proposed framework combines two extended Kalman filters (EKF); the first one, referred to as the integration filter, is dedicated to the improvement of the GPS localization based on data from an inertial navigation system and wheels' encoders. The second EKF implements the V-SLAM process. The linear and angular velocities in the dynamic model of the V-SLAM EKF filter are given by the GPS/INS/Encoders integration filter. On the other hand, the output of the V-SLAM EKF filter is used to update the dynamics estimation in the integration filter and therefore the geo-referenced localization. This solution increases the accuracy and the robustness of the positioning during GPS outage and allows SLAM in less featured environments

  6. A high-resolution computational localization method for transcranial magnetic stimulation mapping.

    Science.gov (United States)

    Aonuma, Shinta; Gomez-Tames, Jose; Laakso, Ilkka; Hirata, Akimasa; Takakura, Tomokazu; Tamura, Manabu; Muragaki, Yoshihiro

    2018-05-15

    Transcranial magnetic stimulation (TMS) is used for the mapping of brain motor functions. The complexity of the brain deters determining the exact localization of the stimulation site using simplified methods (e.g., the region below the center of the TMS coil) or conventional computational approaches. This study aimed to present a high-precision localization method for a specific motor area by synthesizing computed non-uniform current distributions in the brain for multiple sessions of TMS. Peritumoral mapping by TMS was conducted on patients who had intra-axial brain neoplasms located within or close to the motor speech area. The electric field induced by TMS was computed using realistic head models constructed from magnetic resonance images of patients. A post-processing method was implemented to determine a TMS hotspot by combining the computed electric fields for the coil orientations and positions that delivered high motor-evoked potentials during peritumoral mapping. The method was compared to the stimulation site localized via intraoperative direct brain stimulation and navigated TMS. Four main results were obtained: 1) the dependence of the computed hotspot area on the number of peritumoral measurements was evaluated; 2) the estimated localization of the hand motor area in eight non-affected hemispheres was in good agreement with the position of a so-called "hand-knob"; 3) the estimated hotspot areas were not sensitive to variations in tissue conductivity; and 4) the hand motor areas estimated by this proposal and direct electric stimulation (DES) were in good agreement in the ipsilateral hemisphere of four glioma patients. The TMS localization method was validated by well-known positions of the "hand-knob" in brains for the non-affected hemisphere, and by a hotspot localized via DES during awake craniotomy for the tumor-containing hemisphere. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. Three-dimensional mapping of the local interstellar medium with composite data

    Science.gov (United States)

    Capitanio, L.; Lallement, R.; Vergely, J. L.; Elyajouri, M.; Monreal-Ibero, A.

    2017-10-01

    Context. Three-dimensional maps of the Galactic interstellar medium are general astrophysical tools. Reddening maps may be based on the inversion of color excess measurements for individual target stars or on statistical methods using stellar surveys. Three-dimensional maps based on diffuse interstellar bands (DIBs) have also been produced. All methods benefit from the advent of massive surveys and may benefit from Gaia data. Aims: All of the various methods and databases have their own advantages and limitations. Here we present a first attempt to combine different datasets and methods to improve the local maps. Methods: We first updated our previous local dust maps based on a regularized Bayesian inversion of individual color excess data by replacing Hipparcos or photometric distances with Gaia Data Release 1 values when available. Secondly, we complemented this database with a series of ≃5000 color excess values estimated from the strength of the λ15273 DIB toward stars possessing a Gaia parallax. The DIB strengths were extracted from SDSS/APOGEE spectra. Third, we computed a low-resolution map based on a grid of Pan-STARRS reddening measurements by means of a new hierarchical technique and used this map as the prior distribution during the inversion of the two other datasets. Results: The use of Gaia parallaxes introduces significant changes in some areas and globally increases the compactness of the structures. Additional DIB-based data make it possible to assign distances to clouds located behind closer opaque structures and do not introduce contradictory information for the close structures. A more realistic prior distribution instead of a plane-parallel homogeneous distribution helps better define the structures. We validated the results through comparisons with other maps and with soft X-ray data. Conclusions: Our study demonstrates that the combination of various tracers is a potential tool for more accurate maps. An online tool makes it possible to

  8. Study by Hall probe mapping of the trapped flux modification produced by local heating in YBCO HTS bulks for different surface/volume ratios

    International Nuclear Information System (INIS)

    Laurent, Ph; Mathieu, J-P; Mattivi, B; Fagnard, J-F; Meslin, S; Noudem, J G; Ausloos, M; Cloots, R; Vanderbemden, Ph

    2005-01-01

    The aim of this report is to compare the trapped field distribution under a local heating created at the sample edge for different sample morphologies. Hall probe mappings of the magnetic induction trapped in YBCO bulk samples maintained out of thermal equilibrium were performed on YBCO bulk single domains, YBCO single domains with regularly spaced hole arrays, and YBCO superconducting foams. The capability of heat draining was quantified by two criteria: the average induction decay and the size of the thermally affected zone caused by a local heating of the sample. Among the three investigated sample shapes, the drilled single domain displays a trapped induction which is weakly affected by the local heating while displaying a high trapped field. Finally, a simple numerical modelling of the heat flux spreading into a drilled sample is used to suggest some design rules about the hole configuration and their size

  9. Indoor Localization and Radio Map Estimation using Unsupervised Manifold Alignment with Geometry Perturbation

    KAUST Repository

    Majeed, Khaqan

    2015-12-22

    The Received Signal Strength (RSS) based fingerprinting approaches for indoor localization pose a need for updating the fingerprint databases due to dynamic nature of the indoor environment. This process is hectic and time-consuming when the size of the indoor area is large. The semi-supervised approaches reduce this workload and achieve good accuracy around 15% of the fingerprinting load but the performance is severely degraded if it is reduced below this level. We propose an indoor localization framework that uses unsupervised manifold alignment. It requires only 1% of the fingerprinting load, some crowd sourced readings and plan coordinates of the indoor area. The 1% fingerprinting load is used only in perturbing the local geometries of the plan coordinates. The proposed framework achieves less than 5m mean localization error, which is considerably better than semi-supervised approaches at very small amount of fingerprinting load. In addition, the few location estimations together with few fingerprints help to estimate the complete radio map of the indoor environment. The estimation of radio map does not demand extra workload rather it employs the already available information from the proposed indoor localization framework. The testing results for radio map estimation show almost 50% performance improvement by using this information as compared to using only fingerprints.

  10. Indoor Localization and Radio Map Estimation using Unsupervised Manifold Alignment with Geometry Perturbation

    KAUST Repository

    Majeed, Khaqan; Sorour, Sameh; Al-Naffouri, Tareq Y.; Valaee, Shahrokh

    2015-01-01

    The Received Signal Strength (RSS) based fingerprinting approaches for indoor localization pose a need for updating the fingerprint databases due to dynamic nature of the indoor environment. This process is hectic and time-consuming when the size of the indoor area is large. The semi-supervised approaches reduce this workload and achieve good accuracy around 15% of the fingerprinting load but the performance is severely degraded if it is reduced below this level. We propose an indoor localization framework that uses unsupervised manifold alignment. It requires only 1% of the fingerprinting load, some crowd sourced readings and plan coordinates of the indoor area. The 1% fingerprinting load is used only in perturbing the local geometries of the plan coordinates. The proposed framework achieves less than 5m mean localization error, which is considerably better than semi-supervised approaches at very small amount of fingerprinting load. In addition, the few location estimations together with few fingerprints help to estimate the complete radio map of the indoor environment. The estimation of radio map does not demand extra workload rather it employs the already available information from the proposed indoor localization framework. The testing results for radio map estimation show almost 50% performance improvement by using this information as compared to using only fingerprints.

  11. Energy Road-map 2050: Towards regional and local energy Road-maps. IMAGINE seminar 2011

    International Nuclear Information System (INIS)

    Maillot, Herve; Pidoux, Blandine

    2011-11-01

    The 2011 IMAGINE Seminar held in Brussels on 9 November 2011 united around fifty representatives from Energy Cities network member cities as well as representatives from the European Parliament and the Commission, various industrial sectors and civil society organisations. Participants were invited to share their visions of their action by 2040-2050 in a sustainable and desirable city, having achieved its energy transition. The spontaneous and inspiring discussions that followed broached the following questions: - What is and should be the role of the local level in the EU Energy Road-map? - What if European local authorities were to develop their own 'Energy 2050' Road-maps? - What local and regional policies can social and economic players use for contributing to achieving European targets? - Under what conditions is the 'low energy cities with a high quality of life for all' concept relevant? The debate helped outline a shared, global vision as a step towards European collective dynamics giving territories a major role in energy transition. At the end of the day, participants from very different backgrounds converged on the following key points: - Like European institutions, territories must develop a long-term vision, failing which they will be unable to take meaningful action, mobilise players and make the right decisions in the short-term. - The energy-territory relationship, from efficient energy use to supply policies, is a major democratic challenge. - Although a number of technologies are already available, they still have to be integrated so that citizens can satisfy their needs and become fully accountable for their energy use. - Energy strategies must help meet a number of local challenges: social and territorial cohesion, employment and economic development, environmental protection and quality of life. To do so, they need to be designed taking those they are supposed to serve, i.e. citizens, into consideration. - The interaction between local

  12. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods

    International Nuclear Information System (INIS)

    Kleinschmidt, R.; Watson, D.

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km 2 ), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h −1 (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. - Highlights: • A baseline terrestrial air kerma map of Queensland, Australia was developed using geochemical data from a major drainage catchment ultra-low density sampling program

  13. Steepest descent method for set-valued locally accretive mappings

    International Nuclear Information System (INIS)

    Chidume, C.E.

    1993-05-01

    Let E be a real q-uniformly smooth Banach space. Suppose T is a set-valued locally strongly accretive map with open domain D(T) in E and that 0 is an element of Tx has a solution x* in D(T). Then there exists a neighbourhood B in D(T) of x* and a real number r 1 >0 such that for any r>r 1 and some real sequence {c n }, any initial guess x 1 is an element of B and any single-valued selection T 0 of T, the sequence {x n } generated from x 1 by x n+1 =x n -c n T 0 x n , n≥1, remains in D(T) and converges strongly to x* with ||x n -x*|| O(n -(q-1)/ q). A related result deals with iterative approximation of a solution of the equation f is an element of x+Ax when A is a locally accretive map. Our theorems generalize important known results and resolve a problem of interest. (author). 39 refs

  14. On a Hopping-Points SVD and Hough Transform-Based Line Detection Algorithm for Robot Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Abhijeet Ravankar

    2016-05-01

    Full Text Available Line detection is an important problem in computer vision, graphics and autonomous robot navigation. Lines detected using a laser range sensor (LRS mounted on a robot can be used as features to build a map of the environment, and later to localize the robot in the map, in a process known as Simultaneous Localization and Mapping (SLAM. We propose an efficient algorithm for line detection from LRS data using a novel hopping-points Singular Value Decomposition (SVD and Hough transform-based algorithm, in which SVD is applied to intermittent LRS points to accelerate the algorithm. A reverse-hop mechanism ensures that the end points of the line segments are accurately extracted. Line segments extracted from the proposed algorithm are used to form a map and, subsequently, LRS data points are matched with the line segments to localize the robot. The proposed algorithm eliminates the drawbacks of point-based matching algorithms like the Iterative Closest Points (ICP algorithm, the performance of which degrades with an increasing number of points. We tested the proposed algorithm for mapping and localization in both simulated and real environments, and found it to detect lines accurately and build maps with good self-localization.

  15. A proposal for combining mapping, localization and target recognition

    Science.gov (United States)

    Grönwall, Christina; Hendeby, Gustaf; Sinivaara, Kristian

    2015-10-01

    Simultaneous localization and mapping (SLAM) is a well-known positioning approach in GPS-denied environments such as urban canyons and inside buildings. Autonomous/aided target detection and recognition (ATR) is commonly used in military application to detect threats and targets in outdoor environments. This papers present approaches to combine SLAM with ATR in ways that compensate for the drawbacks in each method. The methods use physical objects that are recognizable by ATR as unambiguous features in SLAM, while SLAM provides the ATR with better position estimates. Landmarks in the form of 3D point features based on normal aligned radial features (NARF) are used in conjunction with identified objects and 3D object models that replace landmarks when possible. This leads to a more compact map representation with fewer landmarks, which partly compensates for the introduced cost of the ATR. We analyze three approaches to combine SLAM and 3D-data; point-point matching ignoring NARF features, point-point matching using the set of points that are selected by NARF feature analysis, and matching of NARF features using nearest neighbor analysis. The first two approaches are is similar to the common iterative closest point (ICP). We propose an algorithm that combines EKF-SLAM and ATR based on rectangle estimation. The intended application is to improve the positioning of a first responder moving through an indoor environment, where the map offers localization and simultaneously helps locate people, furniture and potentially dangerous objects such as gas canisters.

  16. Mapping Spaces, Centralizers, and p-Local Finite Groups of Lie Type

    DEFF Research Database (Denmark)

    Laude, Isabelle

    We study the space of maps from the classifying space of a finite p-group to theBorel construction of a finite group of Lie type G in characteristic p acting on itsbuilding. The first main result is a description of the homology with Fp-coefficients,showing that the mapping space, up to p...... between a finite p-group and theuncompleted classifying space of the p-local finite group coming from a finite groupof Lie type in characteristic p, providing some of the first results in this uncompletedsetting.......-completion, is a disjoint union indexedover the group homomorphism up to conjugation of classifying spaces of centralizersof p-subgroups in the underlying group G. We complement this description bydetermining the actual homotopy groups of the mapping space. These resultstranslate to descriptions of the space of maps...

  17. Algebraic models of local period maps and Yukawa algebras

    Science.gov (United States)

    Bandiera, Ruggero; Manetti, Marco

    2018-02-01

    We describe some L_{∞} model for the local period map of a compact Kähler manifold. Applications include the study of deformations with associated variation of Hodge structure constrained by certain closed strata of the Grassmannian of the de Rham cohomology. As a by-product, we obtain an interpretation in the framework of deformation theory of the Yukawa coupling.

  18. Local heterogeneity effects on small-sample worths

    International Nuclear Information System (INIS)

    Schaefer, R.W.

    1986-01-01

    One of the parameters usually measured in a fast reactor critical assembly is the reactivity associated with inserting a small sample of a material into the core (sample worth). Local heterogeneities introduced by the worth measurement techniques can have a significant effect on the sample worth. Unfortunately, the capability is lacking to model some of the heterogeneity effects associated with the experimental technique traditionally used at ANL (the radial tube technique). It has been suggested that these effects could account for a large portion of what remains of the longstanding central worth discrepancy. The purpose of this paper is to describe a large body of experimental data - most of which has never been reported - that shows the effect of radial tube-related local heterogeneities

  19. Position Estimation and Local Mapping Using Omnidirectional Images and Global Appearance Descriptors

    Directory of Open Access Journals (Sweden)

    Yerai Berenguer

    2015-10-01

    Full Text Available This work presents some methods to create local maps and to estimate the position of a mobile robot, using the global appearance of omnidirectional images. We use a robot that carries an omnidirectional vision system on it. Every omnidirectional image acquired by the robot is described only with one global appearance descriptor, based on the Radon transform. In the work presented in this paper, two different possibilities have been considered. In the first one, we assume the existence of a map previously built composed of omnidirectional images that have been captured from previously-known positions. The purpose in this case consists of estimating the nearest position of the map to the current position of the robot, making use of the visual information acquired by the robot from its current (unknown position. In the second one, we assume that we have a model of the environment composed of omnidirectional images, but with no information about the location of where the images were acquired. The purpose in this case consists of building a local map and estimating the position of the robot within this map. Both methods are tested with different databases (including virtual and real images taking into consideration the changes of the position of different objects in the environment, different lighting conditions and occlusions. The results show the effectiveness and the robustness of both methods.

  20. Crowd-Sourced Mobility Mapping for Location Tracking Using Unlabeled Wi-Fi Simultaneous Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Mu Zhou

    2015-01-01

    Full Text Available Due to the increasing requirements of the seamless and round-the-clock Location-based services (LBSs, a growing interest in Wi-Fi network aided location tracking is witnessed in the past decade. One of the significant problems of the conventional Wi-Fi location tracking approaches based on received signal strength (RSS fingerprinting is the time-consuming and labor intensive work involved in location fingerprint calibration. To solve this problem, a novel unlabeled Wi-Fi simultaneous localization and mapping (SLAM approach is developed to avoid the location fingerprinting and additional inertial or vision sensors. In this approach, an unlabeled mobility map of the coverage area is first constructed by using the crowd-sourcing from a batch of sporadically recorded Wi-Fi RSS sequences based on the spectral cluster assembling. Then, the sequence alignment algorithm is applied to conduct location tracking and mobility map updating. Finally, the effectiveness of this approach is verified by the extensive experiments carried out in a campus-wide area.

  1. A simulation of Earthquake Loss Estimation in Southeastern Korea using HAZUS and the local site classification Map

    Science.gov (United States)

    Kang, S.; Kim, K.

    2013-12-01

    Regionally varying seismic hazards can be estimated using an earthquake loss estimation system (e.g. HAZUS-MH). The estimations for actual earthquakes help federal and local authorities develop rapid, effective recovery measures. Estimates for scenario earthquakes help in designing a comprehensive earthquake hazard mitigation plan. Local site characteristics influence the ground motion. Although direct measurements are desirable to construct a site-amplification map, such data are expensive and time consuming to collect. Thus we derived a site classification map of the southern Korean Peninsula using geologic and geomorphologic data, which are readily available for the entire southern Korean Peninsula. Class B sites (mainly rock) are predominant in the area, although localized areas of softer soils are found along major rivers and seashores. The site classification map is compared with independent site classification studies to confirm our site classification map effectively represents the local behavior of site amplification during an earthquake. We then estimated the losses due to a magnitude 6.7 scenario earthquake in Gyeongju, southeastern Korea, with and without the site classification map. Significant differences in loss estimates were observed. The loss without the site classification map decreased without variation with increasing epicentral distance, while the loss with the site classification map varied from region to region, due to both the epicentral distance and local site effects. The major cause of the large loss expected in Gyeongju is the short epicentral distance. Pohang Nam-Gu is located farther from the earthquake source region. Nonetheless, the loss estimates in the remote city are as large as those in Gyeongju and are attributed to the site effect of soft soil found widely in the area.

  2. PRIMAL: Page Rank-Based Indoor Mapping and Localization Using Gene-Sequenced Unlabeled WLAN Received Signal Strength

    Directory of Open Access Journals (Sweden)

    Mu Zhou

    2015-09-01

    Full Text Available Due to the wide deployment of wireless local area networks (WLAN, received signal strength (RSS-based indoor WLAN localization has attracted considerable attention in both academia and industry. In this paper, we propose a novel page rank-based indoor mapping and localization (PRIMAL by using the gene-sequenced unlabeled WLAN RSS for simultaneous localization and mapping (SLAM. Specifically, first of all, based on the observation of the motion patterns of the people in the target environment, we use the Allen logic to construct the mobility graph to characterize the connectivity among different areas of interest. Second, the concept of gene sequencing is utilized to assemble the sporadically-collected RSS sequences into a signal graph based on the transition relations among different RSS sequences. Third, we apply the graph drawing approach to exhibit both the mobility graph and signal graph in a more readable manner. Finally, the page rank (PR algorithm is proposed to construct the mapping from the signal graph into the mobility graph. The experimental results show that the proposed approach achieves satisfactory localization accuracy and meanwhile avoids the intensive time and labor cost involved in the conventional location fingerprinting-based indoor WLAN localization.

  3. PRIMAL: Page Rank-Based Indoor Mapping and Localization Using Gene-Sequenced Unlabeled WLAN Received Signal Strength.

    Science.gov (United States)

    Zhou, Mu; Zhang, Qiao; Xu, Kunjie; Tian, Zengshan; Wang, Yanmeng; He, Wei

    2015-09-25

    Due to the wide deployment of wireless local area networks (WLAN), received signal strength (RSS)-based indoor WLAN localization has attracted considerable attention in both academia and industry. In this paper, we propose a novel page rank-based indoor mapping and localization (PRIMAL) by using the gene-sequenced unlabeled WLAN RSS for simultaneous localization and mapping (SLAM). Specifically, first of all, based on the observation of the motion patterns of the people in the target environment, we use the Allen logic to construct the mobility graph to characterize the connectivity among different areas of interest. Second, the concept of gene sequencing is utilized to assemble the sporadically-collected RSS sequences into a signal graph based on the transition relations among different RSS sequences. Third, we apply the graph drawing approach to exhibit both the mobility graph and signal graph in a more readable manner. Finally, the page rank (PR) algorithm is proposed to construct the mapping from the signal graph into the mobility graph. The experimental results show that the proposed approach achieves satisfactory localization accuracy and meanwhile avoids the intensive time and labor cost involved in the conventional location fingerprinting-based indoor WLAN localization.

  4. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    Energy Technology Data Exchange (ETDEWEB)

    Wanzenboeck, H.D.; Hochleitner, G.; Mika, J.; Shawrav, M.M.; Gavagnin, M.; Bertagnolli, E. [Vienna University of Technology, Institute for Solid State Electronics, Vienna (Austria)

    2014-12-15

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-μm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID. (orig.)

  5. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    International Nuclear Information System (INIS)

    Wanzenboeck, H.D.; Hochleitner, G.; Mika, J.; Shawrav, M.M.; Gavagnin, M.; Bertagnolli, E.

    2014-01-01

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-μm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID. (orig.)

  6. Mapping of local argon impingement on a virtual surface: an insight for gas injection during FEBID

    Science.gov (United States)

    Wanzenboeck, H. D.; Hochleitner, G.; Mika, J.; Shawrav, M. M.; Gavagnin, M.; Bertagnolli, E.

    2014-12-01

    During the last decades, focused electron beam induced deposition (FEBID) has become a successful approach for direct-write fabrication of nanodevices. Such a deposition technique relies on the precursor supply to the sample surface which is typically accomplished by a gas injection system using a tube-shaped injector nozzle. This precursor injection strategy implies a position-dependent concentration gradient on the surface, which affects the geometry and chemistry of the final nanodeposit. Although simulations already proposed the local distribution of nozzle-borne gas molecules impinging on the surface, this isolated step in the FEBID process has never been experimentally measured yet. This work experimentally investigates the local distribution of impinging gas molecules on the sample plane, isolating the direct impingement component from surface diffusion or precursor depletion by deposition. The experimental setup used in this work maps and quantifies the local impinging rate of argon gas over the sample plane. This setup simulates the identical conditions for a precursor molecule during FEBID. Argon gas was locally collected with a sniffer tube, which is directly connected to a residual gas analyzer for quantification. The measured distribution of impinging gas molecules showed a strong position dependence. Indeed, a 300-µm shift of the deposition area to a position further away from the impingement center spot resulted in a 50 % decrease in the precursor impinging rate on the surface area. With the same parameters, the precursor distribution was also simulated by a Monte Carlo software by Friedli and Utke and showed a good correlation between the empirical and the simulated precursor distribution. The results hereby presented underline the importance of controlling the local precursor flux conditions in order to obtain reproducible and comparable deposition results in FEBID.

  7. Generating samples for association studies based on HapMap data

    Directory of Open Access Journals (Sweden)

    Chen Yixuan

    2008-01-01

    Full Text Available Abstract Background With the completion of the HapMap project, a variety of computational algorithms and tools have been proposed for haplotype inference, tag SNP selection and genome-wide association studies. Simulated data are commonly used in evaluating these new developed approaches. In addition to simulations based on population models, empirical data generated by perturbing real data, has also been used because it may inherit specific properties from real data. However, there is no tool that is publicly available to generate large scale simulated variation data by taking into account knowledge from the HapMap project. Results A computer program (gs was developed to quickly generate a large number of samples based on real data that are useful for a variety of purposes, including evaluating methods for haplotype inference, tag SNP selection and association studies. Two approaches have been implemented to generate dense SNP haplotype/genotype data that share similar local linkage disequilibrium (LD patterns as those in human populations. The first approach takes haplotype pairs from samples as inputs, and the second approach takes patterns of haplotype block structures as inputs. Both quantitative and qualitative traits have been incorporated in the program. Phenotypes are generated based on a disease model, or based on the effect of a quantitative trait nucleotide, both of which can be specified by users. In addition to single-locus disease models, two-locus disease models have also been implemented that can incorporate any degree of epistasis. Users are allowed to specify all nine parameters in a 3 × 3 penetrance table. For several commonly used two-locus disease models, the program can automatically calculate penetrances based on the population prevalence and marginal effects of a disease that users can conveniently specify. Conclusion The program gs can effectively generate large scale genetic and phenotypic variation data that can be

  8. Mapping of depleted uranium with in situ spectrometry and soil samples

    International Nuclear Information System (INIS)

    Shebell, P.; Reginatto, M.; Monetti, M.; Faller, S.; Davis, L.

    1999-01-01

    Depleted uranium (DU) has been developed in the past two decades as a highly effective material for armor penetrating rounds and vehicle shielding. There is now a growing interest in the defense community to determine the presence and extent of DU contamination quickly and with a minimum amount of intrusive sampling. We report on a new approach using deconvolution techniques to quantitatively map DU contamination in surface soil. This approach combines data from soil samples with data from in situ gamma-ray spectrometry measurements to produce an accurate and detailed map of DU contamination. Results of a field survey at the Aberdeen Proving Ground are presented. (author)

  9. Mobile Ground-Based Radar Sensor for Localization and Mapping: An Evaluation of two Approaches

    Directory of Open Access Journals (Sweden)

    Damien Vivet

    2013-08-01

    Full Text Available This paper is concerned with robotic applications using a ground-based radar sensor for simultaneous localization and mapping problems. In mobile robotics, radar technology is interesting because of its long range and the robustness of radar waves to atmospheric conditions, making these sensors well-suited for extended outdoor robotic applications. Two localization and mapping approaches using data obtained from a 360° field of view microwave radar sensor are presented and compared. The first method is a trajectory-oriented simultaneous localization and mapping technique, which makes no landmark assumptions and avoids the data association problem. The estimation of the ego-motion makes use of the Fourier-Mellin transform for registering radar images in a sequence, from which the rotation and translation of the sensor motion can be estimated. The second approach uses the consequence of using a rotating range sensor in high speed robotics. In such a situation, movement combinations create distortions in the collected data. Velocimetry is achieved here by explicitly analysing these measurement distortions. As a result, the trajectory of the vehicle and then the radar map of outdoor environments can be obtained. The evaluation of experimental results obtained by the two methods is presented on real-world data from a vehicle moving at 30 km/h over a 2.5 km course.

  10. Two-photon mapping of localized field enhancements in thin nanostrip antennas

    DEFF Research Database (Denmark)

    Beermann, I.; Novikov, S.M.; Søndergaard, Thomas

    2008-01-01

    scanning optical microscopy, in which two-photon-excited photoluminescence (TPL) excited with a strongly focused laser beam at the wavelength 745 nm is detected. We use TPL images to map the local field enhancements from individual nanostrips at a resolution of 0.35µm and compare results with theoretical......Resonant scattering and local field enhancements by 11-nm-thin gold nanostrip antennas due to constructive interference of counter propagating slow surface plasmon polaritons is investigated. We characterize nanostrips of widths between 50-530 nm using both reflection spectroscopy and nonlinear...

  11. Localization and Classification of Paddy Field Pests using a Saliency Map and Deep Convolutional Neural Network

    Science.gov (United States)

    Liu, Ziyi; Gao, Junfeng; Yang, Guoguo; Zhang, Huan; He, Yong

    2016-01-01

    We present a pipeline for the visual localization and classification of agricultural pest insects by computing a saliency map and applying deep convolutional neural network (DCNN) learning. First, we used a global contrast region-based approach to compute a saliency map for localizing pest insect objects. Bounding squares containing targets were then extracted, resized to a fixed size, and used to construct a large standard database called Pest ID. This database was then utilized for self-learning of local image features which were, in turn, used for classification by DCNN. DCNN learning optimized the critical parameters, including size, number and convolutional stride of local receptive fields, dropout ratio and the final loss function. To demonstrate the practical utility of using DCNN, we explored different architectures by shrinking depth and width, and found effective sizes that can act as alternatives for practical applications. On the test set of paddy field images, our architectures achieved a mean Accuracy Precision (mAP) of 0.951, a significant improvement over previous methods. PMID:26864172

  12. Evaluation of macromolecular electron-density map quality using the correlation of local r.m.s. density

    International Nuclear Information System (INIS)

    Terwilliger, Thomas C.; Berendzen, Joel

    1999-01-01

    The correlation of local r.m.s. density is shown to be a good measure of the presence of distinct solvent and macromolecule regions in macromolecular electron-density maps. It has recently been shown that the standard deviation of local r.m.s. electron density is a good indicator of the presence of distinct regions of solvent and protein in macromolecular electron-density maps [Terwilliger & Berendzen (1999 ▶). Acta Cryst. D55, 501–505]. Here, it is demonstrated that a complementary measure, the correlation of local r.m.s. density in adjacent regions on the unit cell, is also a good measure of the presence of distinct solvent and protein regions. The correlation of local r.m.s. density is essentially a measure of how contiguous the solvent (and protein) regions are in the electron-density map. This statistic can be calculated in real space or in reciprocal space and has potential uses in evaluation of heavy-atom solutions in the MIR and MAD methods as well as for evaluation of trial phase sets in ab initio phasing procedures

  13. Can single molecule localization microscopy be used to map closely spaced RGD nanodomains?

    Directory of Open Access Journals (Sweden)

    Mahdie Mollazade

    Full Text Available Cells sense and respond to nanoscale variations in the distribution of ligands to adhesion receptors. This makes single molecule localization microscopy (SMLM an attractive tool to map the distribution of ligands on nanopatterned surfaces. We explore the use of SMLM spatial cluster analysis to detect nanodomains of the cell adhesion-stimulating tripeptide arginine-glycine-aspartic acid (RGD. These domains were formed by the phase separation of block copolymers with controllable spacing on the scale of tens of nanometers. We first determined the topology of the block copolymer with atomic force microscopy (AFM and then imaged the localization of individual RGD peptides with direct stochastic optical reconstruction microscopy (dSTORM. To compare the data, we analyzed the dSTORM data with DBSCAN (density-based spatial clustering application with noise. The ligand distribution and polymer topology are not necessary identical since peptides may attach to the polymer outside the nanodomains and/or coupling and detection of peptides within the nanodomains is incomplete. We therefore performed simulations to explore the extent to which nanodomains could be mapped with dSTORM. We found that successful detection of nanodomains by dSTORM was influenced by the inter-domain spacing and the localization precision of individual fluorophores, and less by non-specific absorption of ligands to the substratum. For example, under our imaging conditions, DBSCAN identification of nanodomains spaced further than 50 nm apart was largely independent of background localisations, while nanodomains spaced closer than 50 nm required a localization precision of ~11 nm to correctly estimate the modal nearest neighbor distance (NDD between nanodomains. We therefore conclude that SMLM is a promising technique to directly map the distribution and nanoscale organization of ligands and would benefit from an improved localization precision.

  14. Mappings for Special Functions on Cantor Sets and Special Integral Transforms via Local Fractional Operators

    Directory of Open Access Journals (Sweden)

    Yang Zhao

    2013-01-01

    Full Text Available The mappings for some special functions on Cantor sets are investigated. Meanwhile, we apply the local fractional Fourier series, Fourier transforms, and Laplace transforms to solve three local fractional differential equations, and the corresponding nondifferentiable solutions were presented.

  15. Three main paradigms of simultaneous localization and mapping (SLAM) problem

    Science.gov (United States)

    Imani, Vandad; Haataja, Keijo; Toivanen, Pekka

    2018-04-01

    Simultaneous Localization and Mapping (SLAM) is one of the most challenging research areas within computer and machine vision for automated scene commentary and explanation. The SLAM technique has been a developing research area in the robotics context during recent years. By utilizing the SLAM method robot can estimate the different positions of the robot at the distinct points of time which can indicate the trajectory of robot as well as generate a map of the environment. SLAM has unique traits which are estimating the location of robot and building a map in the various types of environment. SLAM is effective in different types of environment such as indoor, outdoor district, Air, Underwater, Underground and Space. Several approaches have been investigated to use SLAM technique in distinct environments. The purpose of this paper is to provide an accurate perceptive review of case history of SLAM relied on laser/ultrasonic sensors and camera as perception input data. In addition, we mainly focus on three paradigms of SLAM problem with all its pros and cons. In the future, use intelligent methods and some new idea will be used on visual SLAM to estimate the motion intelligent underwater robot and building a feature map of marine environment.

  16. Local search for optimal global map generation using mid-decadal landsat images

    Science.gov (United States)

    Khatib, L.; Gasch, J.; Morris, Robert; Covington, S.

    2007-01-01

    NASA and the US Geological Survey (USGS) are seeking to generate a map of the entire globe using Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) sensor data from the "mid-decadal" period of 2004 through 2006. The global map is comprised of thousands of scene locations and, for each location, tens of different images of varying quality to chose from. Furthermore, it is desirable for images of adjacent scenes be close together in time of acquisition, to avoid obvious discontinuities due to seasonal changes. These characteristics make it desirable to formulate an automated solution to the problem of generating the complete map. This paper formulates a Global Map Generator problem as a Constraint Optimization Problem (GMG-COP) and describes an approach to solving it using local search. Preliminary results of running the algorithm on image data sets are summarized. The results suggest a significant improvement in map quality using constraint-based solutions. Copyright ?? 2007, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved.

  17. 36 CFR 9.42 - Well records and reports, plots and maps, samples, tests and surveys.

    Science.gov (United States)

    2010-07-01

    ... Well records and reports, plots and maps, samples, tests and surveys. Any technical data gathered... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Well records and reports, plots and maps, samples, tests and surveys. 9.42 Section 9.42 Parks, Forests, and Public Property...

  18. Terrestrial gamma radiation baseline mapping using ultra low density sampling methods.

    Science.gov (United States)

    Kleinschmidt, R; Watson, D

    2016-01-01

    Baseline terrestrial gamma radiation maps are indispensable for providing basic reference information that may be used in assessing the impact of a radiation related incident, performing epidemiological studies, remediating land contaminated with radioactive materials, assessment of land use applications and resource prospectivity. For a large land mass, such as Queensland, Australia (over 1.7 million km(2)), it is prohibitively expensive and practically difficult to undertake detailed in-situ radiometric surveys of this scale. It is proposed that an existing, ultra-low density sampling program already undertaken for the purpose of a nationwide soil survey project be utilised to develop a baseline terrestrial gamma radiation map. Geoelement data derived from the National Geochemistry Survey of Australia (NGSA) was used to construct a baseline terrestrial gamma air kerma rate map, delineated by major drainage catchments, for Queensland. Three drainage catchments (sampled at the catchment outlet) spanning low, medium and high radioelement concentrations were selected for validation of the methodology using radiometric techniques including in-situ measurements and soil sampling for high resolution gamma spectrometry, and comparative non-radiometric analysis. A Queensland mean terrestrial air kerma rate, as calculated from the NGSA outlet sediment uranium, thorium and potassium concentrations, of 49 ± 69 nGy h(-1) (n = 311, 3σ 99% confidence level) is proposed as being suitable for use as a generic terrestrial air kerma rate background range. Validation results indicate that catchment outlet measurements are representative of the range of results obtained across the catchment and that the NGSA geoelement data is suitable for calculation and mapping of terrestrial air kerma rate. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  19. A 2.5D Map-Based Mobile Robot Localization via Cooperation of Aerial and Ground Robots.

    Science.gov (United States)

    Nam, Tae Hyeon; Shim, Jae Hong; Cho, Young Im

    2017-11-25

    Recently, there has been increasing interest in studying the task coordination of aerial and ground robots. When a robot begins navigation in an unknown area, it has no information about the surrounding environment. Accordingly, for robots to perform tasks based on location information, they need a simultaneous localization and mapping (SLAM) process that uses sensor information to draw a map of the environment, while simultaneously estimating the current location of the robot on the map. This paper aims to present a localization method based in cooperation between aerial and ground robots in an indoor environment. The proposed method allows a ground robot to reach accurate destination by using a 2.5D elevation map built by a low-cost RGB-D (Red Green and Blue-Depth) sensor and 2D Laser sensor attached onto an aerial robot. A 2.5D elevation map is formed by projecting height information of an obstacle using depth information obtained by the RGB-D sensor onto a grid map, which is generated by using the 2D Laser sensor and scan matching. Experimental results demonstrate the effectiveness of the proposed method for its accuracy in location recognition and computing speed.

  20. A 2.5D Map-Based Mobile Robot Localization via Cooperation of Aerial and Ground Robots

    Directory of Open Access Journals (Sweden)

    Tae Hyeon Nam

    2017-11-01

    Full Text Available Recently, there has been increasing interest in studying the task coordination of aerial and ground robots. When a robot begins navigation in an unknown area, it has no information about the surrounding environment. Accordingly, for robots to perform tasks based on location information, they need a simultaneous localization and mapping (SLAM process that uses sensor information to draw a map of the environment, while simultaneously estimating the current location of the robot on the map. This paper aims to present a localization method based in cooperation between aerial and ground robots in an indoor environment. The proposed method allows a ground robot to reach accurate destination by using a 2.5D elevation map built by a low-cost RGB-D (Red Green and Blue-Depth sensor and 2D Laser sensor attached onto an aerial robot. A 2.5D elevation map is formed by projecting height information of an obstacle using depth information obtained by the RGB-D sensor onto a grid map, which is generated by using the 2D Laser sensor and scan matching. Experimental results demonstrate the effectiveness of the proposed method for its accuracy in location recognition and computing speed.

  1. Adopting the FAB-MAP algorithm for indoor localization with WiFi fingerprints

    OpenAIRE

    Wietrzykowski, Jan; Nowicki, Michał; Skrzypczyński, Piotr

    2016-01-01

    Personal indoor localization is usually accomplished by fusing information from various sensors. A common choice is to use the WiFi adapter that provides information about Access Points that can be found in the vicinity. Unfortunately, state-of-the-art approaches to WiFi-based localization often employ very dense maps of the WiFi signal distribution, and require a time-consuming process of parameter selection. On the other hand, camera images are commonly used for visual place recognition, de...

  2. Localized Multiple Kernel Learning Via Sample-Wise Alternating Optimization.

    Science.gov (United States)

    Han, Yina; Yang, Kunde; Ma, Yuanliang; Liu, Guizhong

    2014-01-01

    Our objective is to train support vector machines (SVM)-based localized multiple kernel learning (LMKL), using the alternating optimization between the standard SVM solvers with the local combination of base kernels and the sample-specific kernel weights. The advantage of alternating optimization developed from the state-of-the-art MKL is the SVM-tied overall complexity and the simultaneous optimization on both the kernel weights and the classifier. Unfortunately, in LMKL, the sample-specific character makes the updating of kernel weights a difficult quadratic nonconvex problem. In this paper, starting from a new primal-dual equivalence, the canonical objective on which state-of-the-art methods are based is first decomposed into an ensemble of objectives corresponding to each sample, namely, sample-wise objectives. Then, the associated sample-wise alternating optimization method is conducted, in which the localized kernel weights can be independently obtained by solving their exclusive sample-wise objectives, either linear programming (for l1-norm) or with closed-form solutions (for lp-norm). At test time, the learnt kernel weights for the training data are deployed based on the nearest-neighbor rule. Hence, to guarantee their generality among the test part, we introduce the neighborhood information and incorporate it into the empirical loss when deriving the sample-wise objectives. Extensive experiments on four benchmark machine learning datasets and two real-world computer vision datasets demonstrate the effectiveness and efficiency of the proposed algorithm.

  3. Environment mapping and localization with an uncontrolled swarm of ultrasound sensor motes

    NARCIS (Netherlands)

    Duisterwinkel, E.; Demi, L.; Dubbelman, G.; Talnishnikh, E.; Wörtche, H.J.; Bergmans, J.W.M.

    2014-01-01

    A method is presented in which a (large) swarm of sensor motes perform simple ultrasonic ranging measurements. The method allows to localize the motes within the swarm, and at the same time, map the environment which the swarm has traversed. The motes float passively uncontrolled through the

  4. 17. Annotations to the map of the more important fossil localities in the Netherlands East Indies

    NARCIS (Netherlands)

    Krijnen, W.F.

    1931-01-01

    For the compilation of the map of fossil localities I have followed the example of Dr. A. Tobler (bibl. 194), arranging the localities according to age. The localities from which more than one formation has been recorded, are numbered for the oldest formation found. In the list these numbers are

  5. Local Relation Map: A Novel Illumination Invariant Face Recognition Approach

    Directory of Open Access Journals (Sweden)

    Lian Zhichao

    2012-10-01

    Full Text Available In this paper, a novel illumination invariant face recognition approach is proposed. Different from most existing methods, an additive term as noise is considered in the face model under varying illuminations in addition to a multiplicative illumination term. High frequency coefficients of Discrete Cosine Transform (DCT are discarded to eliminate the effect caused by noise. Based on the local characteristics of the human face, a simple but effective illumination invariant feature local relation map is proposed. Experimental results on the Yale B, Extended Yale B and CMU PIE demonstrate the outperformance and lower computational burden of the proposed method compared to other existing methods. The results also demonstrate the validity of the proposed face model and the assumption on noise.

  6. The role of Urbis' noise and noise effects maps in local policy

    NARCIS (Netherlands)

    Borst, H.C.

    2001-01-01

    An important aspect of the EU noise policy is mapping of noise and noise effects and the formulation of noise action plans. In the Netherlands, due to the new policy on noise (MIG), the municipalities will be responsible for the formulation of a local noise policy. An instrument for the assessment

  7. Using Environmental Variables for Studying of the Quality of Sampling in Soil Mapping

    Directory of Open Access Journals (Sweden)

    A. Jafari

    2016-02-01

    Full Text Available Introduction: Methods of soil survey are generally empirical and based on the mental development of the surveyor, correlating soil with underlying geology, landforms, vegetation and air-photo interpretation. Since there are no statistical criteria for traditional soil sampling; this may lead to bias in the areas being sampled. In digital soil mapping, soil samples may be used to elaborate quantitative relationships or models between soil attributes and soil covariates. Because the relationships are based on the soil observations, the quality of the resulting soil map depends also on the soil observation quality. An appropriate sampling design for digital soil mapping depends on how much data is available and where the data is located. Some statistical methods have been developed for optimizing data sampling for soil surveys. Some of these methods deal with the use of ancillary information. The purpose of this study was to evaluate the quality of sampling of existing data. Materials and Methods: The study area is located in the central basin of the Iranian plateau (Figure 1. The geologic infrastructure of the area is mainly Cretaceous limestone, Mesozoic shale and sandstone. Air photo interpretation (API was used to differentiate geomorphic patterns based on their formation processes, general structure and morphometry. The patterns were differentiated through a nested geomorphic hierarchy (Fig. 2. A four-level geomorphic hierarchy is used to breakdown the complexity of different landscapes of the study area. In the lower level of the hierarchy, the geomorphic surfaces, which were formed by a unique process during a specific geologic time, were defined. A stratified sampling scheme was designed based on geomorphic mapping. In the stratified simple random sampling, the area was divided into sub-areas referred to as strata based on geomorphic surfaces, and within each stratum, sampling locations were randomly selected (Figure 2. This resulted in 191

  8. Automatic traveltime picking using local time-frequency maps

    KAUST Repository

    Saragiotis, Christos

    2011-01-01

    The arrival times of distinct and sufficiently concentrated signals can be computed using Fourier transforms. In real seis- mograms, however, signals are far from distinct. We use local time-frequency maps of the seismograms and its frequency derivatives to obtain frequency-dependent (instantaneous) traveltimes. A smooth division is utilized to control the resolution of the instantaneous traveltimes to allow for a trade-off between resolution and stability. We average these traveltimes over the frequency band which is data-dependent. The resulting traveltime attribute is used to isolate different signals in seismic traces. We demonstrate the effectiveness of this automatic method for picking arrivals by applying it on synthetic and real data. © 2011 Society of Exploration Geophysicists.

  9. Gas source localization and gas distribution mapping with a micro-drone

    International Nuclear Information System (INIS)

    Neumann, Patrick P.

    2013-01-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF-based GSL algorithm

  10. Gas source localization and gas distribution mapping with a micro-drone

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Patrick P.

    2013-07-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF

  11. Gas source localization and gas distribution mapping with a micro-drone

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Patrick P.

    2013-07-01

    The objective of this Ph.D. thesis is the development and validation of a VTOL-based (Vertical Take Off and Landing) micro-drone for the measurement of gas concentrations, to locate gas emission sources, and to build gas distribution maps. Gas distribution mapping and localization of a static gas source are complex tasks due to the turbulent nature of gas transport under natural conditions and becomes even more challenging when airborne. This is especially so, when using a VTOL-based micro-drone that induces disturbances through its rotors, which heavily affects gas distribution. Besides the adaptation of a micro-drone for gas concentration measurements, a novel method for the determination of the wind vector in real-time is presented. The on-board sensors for the flight control of the micro-drone provide a basis for the wind vector calculation. Furthermore, robot operating software for controlling the micro-drone autonomously is developed and used to validate the algorithms developed within this Ph.D. thesis in simulations and real-world experiments. Three biologically inspired algorithms for locating gas sources are adapted and developed for use with the micro-drone: the surge-cast algorithm (a variant of the silkworm moth algorithm), the zigzag / dung beetle algorithm, and a newly developed algorithm called ''pseudo gradient algorithm''. The latter extracts from two spatially separated measuring positions the information necessary (concentration gradient and mean wind direction) to follow a gas plume to its emission source. The performance of the algorithms is evaluated in simulations and real-world experiments. The distance overhead and the gas source localization success rate are used as main performance criteria for comparing the algorithms. Next, a new method for gas source localization (GSL) based on a particle filter (PF) is presented. Each particle represents a weighted hypothesis of the gas source position. As a first step, the PF-based GSL algorithm

  12. Determining Coastal Hazards Risk Perception to Enhance Local Mitigation Planning through a Participatory Mapping Approach

    Science.gov (United States)

    Bethel, M.; Braud, D.; Lambeth, T.; Biber, P.; Wu, W.

    2017-12-01

    Coastal community leaders, government officials, and natural resource managers must be able to accurately assess and predict a given coastal landscape's sustainability and/or vulnerability as coastal habitat continues to undergo rapid and dramatic changes associated with natural and anthropogenic activities such as accelerated relative sea level rise (SLR). To help address this information need, a multi-disciplinary project team conducted Sea Grant sponsored research in Louisiana and Mississippi with traditional ecosystem users and natural resource managers to determine a method for producing localized vulnerability and sustainability maps for projected SLR and storm surge impacts, and determine how and whether the results of such an approach can provide more useful information to enhance hazard mitigation planning. The goals of the project are to develop and refine SLR visualization tools for local implementation in areas experiencing subsidence and erosion, and discover the different ways stakeholder groups evaluate risk and plan mitigation strategies associated with projected SLR and storm surge. Results from physical information derived from data and modeling of subsidence, erosion, engineered restoration and coastal protection features, historical land loss, and future land projections under SLR are integrated with complimentary traditional ecological knowledge (TEK) offered by the collaborating local ecosystem users for these assessments. The data analysis involves interviewing stakeholders, coding the interviews for themes, and then converting the themes into vulnerability and sustainability factors. Each factor is weighted according to emphasis by the TEK experts and number of experts who mention it to determine which factors are the highest priority. The priority factors are then mapped with emphasis on the perception of contributing to local community vulnerability or sustainability to SLR and storm surge. The maps are used by the collaborators to benefit

  13. Performance of Global-Appearance Descriptors in Map Building and Localization Using Omnidirectional Vision

    Directory of Open Access Journals (Sweden)

    Luis Payá

    2014-02-01

    Full Text Available Map building and localization are two crucial abilities that autonomous robots must develop. Vision sensors have become a widespread option to solve these problems. When using this kind of sensors, the robot must extract the necessary information from the scenes to build a representation of the environment where it has to move and to estimate its position and orientation with robustness. The techniques based on the global appearance of the scenes constitute one of the possible approaches to extract this information. They consist in representing each scene using only one descriptor which gathers global information from the scene. These techniques present some advantages comparing to other classical descriptors, based on the extraction of local features. However, it is important a good configuration of the parameters to reach a compromise between computational cost and accuracy. In this paper we make an exhaustive comparison among some global appearance descriptors to solve the mapping and localization problem. With this aim, we make use of several image sets captured in indoor environments under realistic working conditions. The datasets have been collected using an omnidirectional vision sensor mounted on the robot.

  14. Improving mapping for Ebola response through mobilising a local community with self-owned smartphones: Tonkolili District, Sierra Leone, January 2015.

    Directory of Open Access Journals (Sweden)

    Laura M Nic Lochlainn

    Full Text Available During the 2014-16 Ebola virus disease (EVD outbreak, the Magburaka Ebola Management Centre (EMC operated by Médecins Sans Frontières (MSF in Tonkolili District, Sierra Leone, identified that available district maps lacked up-to-date village information to facilitate timely implementation of EVD control strategies. In January 2015, we undertook a survey in chiefdoms within the MSF EMC catchment area to collect mapping and village data. We explore the feasibility and cost to mobilise a local community for this survey, describe validation against existing mapping sources and use of the data to prioritise areas for interventions, and lessons learned.We recruited local people with self-owned Android smartphones installed with open-source survey software (OpenDataKit (ODK and open-source navigation software (OpenStreetMap Automated Navigation Directions (OsmAnd. Surveyors were paired with local motorbike drivers to travel to eligible villages. The collected mapping data were validated by checking for duplication and comparing the village names against a pre-existing village name and location list using a geographic distance and text string-matching algorithm.The survey teams gained sufficient familiarity with the ODK and OsmAnd software within 1-2 hours. Nine chiefdoms in Tonkolili District and three in Bombali District were surveyed within two weeks. Following de-duplication, the surveyors collected data from 891 villages with an estimated 127,021 households. The overall survey cost was €3,395; €3.80 per village surveyed. The MSF GIS team (MSF-OCG created improved maps for the MSF Magburaka EMC team which were used to support surveillance, investigation of suspect EVD cases, hygiene-kit distribution and EVD survivor support. We shared the mapping data with OpenStreetMap, the local Ministry of Health and Sanitation and Sierra Leone District and National Ebola Response Centres.Involving local community and using accessible technology allowed

  15. Improving mapping for Ebola response through mobilising a local community with self-owned smartphones: Tonkolili District, Sierra Leone, January 2015.

    Science.gov (United States)

    Nic Lochlainn, Laura M; Gayton, Ivan; Theocharopoulos, Georgios; Edwards, Robin; Danis, Kostas; Kremer, Ronald; Kleijer, Karline; Tejan, Sumaila M; Sankoh, Mohamed; Jimissa, Augustin; Greig, Jane; Caleo, Grazia

    2018-01-01

    During the 2014-16 Ebola virus disease (EVD) outbreak, the Magburaka Ebola Management Centre (EMC) operated by Médecins Sans Frontières (MSF) in Tonkolili District, Sierra Leone, identified that available district maps lacked up-to-date village information to facilitate timely implementation of EVD control strategies. In January 2015, we undertook a survey in chiefdoms within the MSF EMC catchment area to collect mapping and village data. We explore the feasibility and cost to mobilise a local community for this survey, describe validation against existing mapping sources and use of the data to prioritise areas for interventions, and lessons learned. We recruited local people with self-owned Android smartphones installed with open-source survey software (OpenDataKit (ODK)) and open-source navigation software (OpenStreetMap Automated Navigation Directions (OsmAnd)). Surveyors were paired with local motorbike drivers to travel to eligible villages. The collected mapping data were validated by checking for duplication and comparing the village names against a pre-existing village name and location list using a geographic distance and text string-matching algorithm. The survey teams gained sufficient familiarity with the ODK and OsmAnd software within 1-2 hours. Nine chiefdoms in Tonkolili District and three in Bombali District were surveyed within two weeks. Following de-duplication, the surveyors collected data from 891 villages with an estimated 127,021 households. The overall survey cost was €3,395; €3.80 per village surveyed. The MSF GIS team (MSF-OCG) created improved maps for the MSF Magburaka EMC team which were used to support surveillance, investigation of suspect EVD cases, hygiene-kit distribution and EVD survivor support. We shared the mapping data with OpenStreetMap, the local Ministry of Health and Sanitation and Sierra Leone District and National Ebola Response Centres. Involving local community and using accessible technology allowed rapid

  16. Using ESRI Story Maps for Engaging Tribal Youth in Localized Climate Education

    Science.gov (United States)

    Masters, E. L.; Marsik, F. J.; Sonderegger, C.

    2017-12-01

    A critical step in any climate adaptation initiative is the engagement of the community through educational outreach about the impacts of climate change on vulnerable economic, infrastructure and natural resources within the community. For Tribal communities, such outreach must also highlight connections between these vulnerable assets, such as natural resources, and Tribal cultural practices. For adult members of these communities, the combination of traditional ecological knowledge and western science approaches can prove effective in this regard. For Tribal youth, the often complex and data-heavy nature of western science approaches may prove to be more of an obstacle than an aid in communicating the impacts of our changing climate on their local Tribal community. A collaborative educational effort between the Grand Traverse Band of Ottawa and Chippewa Indians (Peshawbestown, MI) and the University of Michigan seeks to lean upon the rich tradition of storytelling as a method of conveying information to younger generations. The ESRI Story Maps platform provides such a tool through its combined use of narratives, images, maps, and data. The ability to make a Story Map deep and complex, or simple and fun, makes this application ideal for communicating with a range of people, from school-age children to adults. For our project, we created two Story Maps with different complexity levels, with one for elementary to middle school students, and the other targeted at high school students. The project for younger children was aimed at engaging viewers through a series of images and maps, introducing them to the basics of what wetlands are, which types of wetlands can be found locally, Indigenous cultural connections to wetlands, and how to protect wetlands. The more complex project provided a more expansive discussion of these same topics, including threats to these wetlands from human activities, including climate change, as well as an extensive list of references and a

  17. Self-organizing adaptive map: autonomous learning of curves and surfaces from point samples.

    Science.gov (United States)

    Piastra, Marco

    2013-05-01

    Competitive Hebbian Learning (CHL) (Martinetz, 1993) is a simple and elegant method for estimating the topology of a manifold from point samples. The method has been adopted in a number of self-organizing networks described in the literature and has given rise to related studies in the fields of geometry and computational topology. Recent results from these fields have shown that a faithful reconstruction can be obtained using the CHL method only for curves and surfaces. Within these limitations, these findings constitute a basis for defining a CHL-based, growing self-organizing network that produces a faithful reconstruction of an input manifold. The SOAM (Self-Organizing Adaptive Map) algorithm adapts its local structure autonomously in such a way that it can match the features of the manifold being learned. The adaptation process is driven by the defects arising when the network structure is inadequate, which cause a growth in the density of units. Regions of the network undergo a phase transition and change their behavior whenever a simple, local condition of topological regularity is met. The phase transition is eventually completed across the entire structure and the adaptation process terminates. In specific conditions, the structure thus obtained is homeomorphic to the input manifold. During the adaptation process, the network also has the capability to focus on the acquisition of input point samples in critical regions, with a substantial increase in efficiency. The behavior of the network has been assessed experimentally with typical data sets for surface reconstruction, including suboptimal conditions, e.g. with undersampling and noise. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Communication: Quantitative multi-site frequency maps for amide I vibrational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Reppert, Mike [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Department of Chemistry, University of Chicago, Chicago, Illinois 60637 (United States); Tokmakoff, Andrei, E-mail: tokmakoff@uchicago.edu [Department of Chemistry, University of Chicago, Chicago, Illinois 60637 (United States)

    2015-08-14

    An accurate method for predicting the amide I vibrational spectrum of a given protein structure has been sought for many years. Significant progress has been made recently by sampling structures from molecular dynamics simulations and mapping local electrostatic variables onto the frequencies of individual amide bonds. Agreement with experiment, however, has remained largely qualitative. Previously, we used dipeptide fragments and isotope-labeled constructs of the protein G mimic NuG2b as experimental standards for developing and testing amide I frequency maps. Here, we combine these datasets to test different frequency-map models and develop a novel method to produce an optimized four-site potential (4P) map based on the CHARMM27 force field. Together with a charge correction for glycine residues, the optimized map accurately describes both experimental datasets, with average frequency errors of 2–3 cm{sup −1}. This 4P map is shown to be convertible to a three-site field map which provides equivalent performance, highlighting the viability of both field- and potential-based maps for amide I spectral modeling. The use of multiple sampling points for local electrostatics is found to be essential for accurate map performance.

  19. Sampling Realistic Protein Conformations Using Local Structural Bias

    DEFF Research Database (Denmark)

    Hamelryck, Thomas Wim; Kent, John T.; Krogh, A.

    2006-01-01

    The prediction of protein structure from sequence remains a major unsolved problem in biology. The most successful protein structure prediction methods make use of a divide-and-conquer strategy to attack the problem: a conformational sampling method generates plausible candidate structures, which...... are subsequently accepted or rejected using an energy function. Conceptually, this often corresponds to separating local structural bias from the long-range interactions that stabilize the compact, native state. However, sampling protein conformations that are compatible with the local structural bias encoded...... in a given protein sequence is a long-standing open problem, especially in continuous space. We describe an elegant and mathematically rigorous method to do this, and show that it readily generates native-like protein conformations simply by enforcing compactness. Our results have far-reaching implications...

  20. 3D mapping of cerebrospinal fluid local volume changes in patients with hydrocephalus treated by surgery: preliminary study

    International Nuclear Information System (INIS)

    Hodel, Jerome; Besson, Pierre; Pruvo, Jean-Pierre; Leclerc, Xavier; Rahmouni, Alain; Grandjacques, Benedicte; Luciani, Alain; Petit, Eric; Lebret, Alain; Outteryck, Olivier; Benadjaoud, Mohamed Amine; Maraval, Anne; Decq, Philippe

    2014-01-01

    To develop automated deformation modelling for the assessment of cerebrospinal fluid (CSF) local volume changes in patients with hydrocephalus treated by surgery. Ventricular and subarachnoid CSF volume changes were mapped by calculating the Jacobian determinant of the deformation fields obtained after non-linear registration of pre- and postoperative images. A total of 31 consecutive patients, 15 with communicating hydrocephalus (CH) and 16 with non-communicating hydrocephalus (NCH), were investigated before and after surgery using a 3D SPACE (sampling perfection with application optimised contrast using different flip-angle evolution) sequence. Two readers assessed CSF volume changes using 3D colour-encoded maps. The Evans index and postoperative volume changes of the lateral ventricles and sylvian fissures were quantified and statistically compared. Before surgery, sylvian fissure and brain ventricle volume differed significantly between CH and NCH (P = 0.001 and P = 0.025, respectively). After surgery, 3D colour-encoded maps allowed for the visual recognition of the CSF volume changes in all patients. The amounts of ventricle volume loss of CH and NCH patients were not significantly different (P = 0.30), whereas readjustment of the sylvian fissure volume was conflicting in CH and NCH patients (P < 0.001). The Evans index correlated with ventricle volume in NCH patients. 3D mapping of CSF volume changes is feasible providing a quantitative follow-up of patients with hydrocephalus. (orig.)

  1. 3D mapping of cerebrospinal fluid local volume changes in patients with hydrocephalus treated by surgery: preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Hodel, Jerome [Hopital Roger Salengro, Department of Neuroradiology, Lille (France); Hopital Roger Salengro, Service de Neuroradiologie, Lille (France); Besson, Pierre; Pruvo, Jean-Pierre; Leclerc, Xavier [Hopital Roger Salengro, Department of Neuroradiology, Lille (France); Rahmouni, Alain; Grandjacques, Benedicte; Luciani, Alain [Hopital Henri Mondor, Department of Radiology, Creteil (France); Petit, Eric; Lebret, Alain [Signals Images and Intelligent Systems Laboratory, Creteil (France); Outteryck, Olivier [Hopital Roger Salengro, Department of Neurology, Lille (France); Benadjaoud, Mohamed Amine [Radiation Epidemiology Team, CESP, Centre for Research in Epidemiology and Population Health U1018, Villejuif (France); Maraval, Anne [Hopital Henri Mondor, Department of Neuroradiology, Creteil (France); Decq, Philippe [Hopital Henri Mondor, Department of Neurosurgery, Creteil (France)

    2014-01-15

    To develop automated deformation modelling for the assessment of cerebrospinal fluid (CSF) local volume changes in patients with hydrocephalus treated by surgery. Ventricular and subarachnoid CSF volume changes were mapped by calculating the Jacobian determinant of the deformation fields obtained after non-linear registration of pre- and postoperative images. A total of 31 consecutive patients, 15 with communicating hydrocephalus (CH) and 16 with non-communicating hydrocephalus (NCH), were investigated before and after surgery using a 3D SPACE (sampling perfection with application optimised contrast using different flip-angle evolution) sequence. Two readers assessed CSF volume changes using 3D colour-encoded maps. The Evans index and postoperative volume changes of the lateral ventricles and sylvian fissures were quantified and statistically compared. Before surgery, sylvian fissure and brain ventricle volume differed significantly between CH and NCH (P = 0.001 and P = 0.025, respectively). After surgery, 3D colour-encoded maps allowed for the visual recognition of the CSF volume changes in all patients. The amounts of ventricle volume loss of CH and NCH patients were not significantly different (P = 0.30), whereas readjustment of the sylvian fissure volume was conflicting in CH and NCH patients (P < 0.001). The Evans index correlated with ventricle volume in NCH patients. 3D mapping of CSF volume changes is feasible providing a quantitative follow-up of patients with hydrocephalus. (orig.)

  2. Novel Mobile Robot Simultaneous Localization and Mapping Using Rao-Blackwellised Particle Filter

    Directory of Open Access Journals (Sweden)

    Hong Bingrong

    2008-11-01

    Full Text Available This paper presents the novel method of mobile robot simultaneous localization and mapping (SLAM, which is implemented by using the Rao-Blackwellised particle filter (RBPF for monocular vision-based autonomous robot in unknown indoor environment. The particle filter is combined with unscented Kalman filter (UKF to extending the path posterior by sampling new poses that integrate the current observation. The landmark position estimation and update is implemented through the unscented transform (UT. Furthermore, the number of resampling steps is determined adaptively, which seriously reduces the particle depletion problem. Monocular CCD camera mounted on the robot tracks the 3D natural point landmarks, which are structured with matching image feature pairs extracted through Scale Invariant Feature Transform (SIFT. The matching for multi-dimension SIFT features which are highly distinctive due to a special descriptor is implemented with a KDTree in the time cost of O(log2N. Experiments on the robot Pioneer3 in our real indoor environment show that our method is of high precision and stability.

  3. Relationship between accuracy and number of samples on statistical quantity and contour map of environmental gamma-ray dose rate. Example of random sampling

    International Nuclear Information System (INIS)

    Matsuda, Hideharu; Minato, Susumu

    2002-01-01

    The accuracy of statistical quantity like the mean value and contour map obtained by measurement of the environmental gamma-ray dose rate was evaluated by random sampling of 5 different model distribution maps made by the mean slope, -1.3, of power spectra calculated from the actually measured values. The values were derived from 58 natural gamma dose rate data reported worldwide ranging in the means of 10-100 Gy/h rates and 10 -3 -10 7 km 2 areas. The accuracy of the mean value was found around ±7% even for 60 or 80 samplings (the most frequent number) and the standard deviation had the accuracy less than 1/4-1/3 of the means. The correlation coefficient of the frequency distribution was found 0.860 or more for 200-400 samplings (the most frequent number) but of the contour map, 0.502-0.770. (K.H.)

  4. High-resolution AUV mapping and sampling of a deep hydrocarbon plume in the Gulf of Mexico

    Science.gov (United States)

    Ryan, J. P.; Zhang, Y.; Thomas, H.; Rienecker, E.; Nelson, R.; Cummings, S.

    2010-12-01

    During NOAA cruise GU-10-02 on the Ship Gordon Gunter, the Monterey Bay Aquarium Research Institute (MBARI) autonomous underwater vehicle (AUV) Dorado was deployed to map and sample a deep (900-1200 m) volume centered approximately seven nautical miles southwest of the Deepwater Horizon wellhead. Dorado was equipped to detect optical and chemical signals of hydrocarbons and to acquire targeted samples. The primary sensor reading used for hydrocarbon detection was colored dissolved organic matter (CDOM) fluorescence (CF). On June 2 and 3, ship cast and subsequent AUV surveys detected elevated CF in a layer between 1100 and 1200 m depth. While the deep volume was mapped in a series of parallel vertical sections, the AUV ran a peak-capture algorithm to target sample acquisition at layer signal peaks. Samples returned by ship CTD/CF rosette sampling and by AUV were preliminarily examined at sea, and they exhibited odor and fluorometric signal consistent with oil. More definitive and detailed results on these samples are forthcoming from shore-based laboratory analyses. During post-cruise analysis, all of the CF data were analyzed to objectively define and map the deep plume feature. Specifically, the maximum expected background CF over the depth range 1000-1200 m was extrapolated from a linear relationship between depth and maximum CF over the depth range 200 to 1000 m. Values exceeding the maximum expected background in the depth range 1000-1200 m were interpreted as signal from a hydrocarbon-enriched plume. Using this definition we examine relationships between CF and other AUV measurements within the plume, illustrate the three-dimensional structure of the plume boundary region that was mapped, describe small-scale layering on isopycnals, and examine short-term variations in plume depth, intensity and hydrographic relationships. Three-dimensional representation of part of a deep hydrocarbon plume mapped and sampled by AUV on June 2-3, 2010.

  5. Mapping regional livelihood benefits from local ecosystem services assessments in rural Sahel.

    Science.gov (United States)

    Malmborg, Katja; Sinare, Hanna; Enfors Kautsky, Elin; Ouedraogo, Issa; Gordon, Line J

    2018-01-01

    Most current approaches to landscape scale ecosystem service assessments rely on detailed secondary data. This type of data is seldom available in regions with high levels of poverty and strong local dependence on provisioning ecosystem services for livelihoods. We develop a method to extrapolate results from a previously published village scale ecosystem services assessment to a higher administrative level, relevant for land use decision making. The method combines remote sensing (using a hybrid classification method) and interviews with community members. The resulting landscape scale maps show the spatial distribution of five different livelihood benefits (nutritional diversity, income, insurance/saving, material assets and energy, and crops for consumption) that illustrate the strong multifunctionality of the Sahelian landscapes. The maps highlight the importance of a diverse set of sub-units of the landscape in supporting Sahelian livelihoods. We see a large potential in using the resulting type of livelihood benefit maps for guiding future land use decisions in the Sahel.

  6. Mapping regional livelihood benefits from local ecosystem services assessments in rural Sahel

    Science.gov (United States)

    Sinare, Hanna; Enfors Kautsky, Elin; Ouedraogo, Issa; Gordon, Line J.

    2018-01-01

    Most current approaches to landscape scale ecosystem service assessments rely on detailed secondary data. This type of data is seldom available in regions with high levels of poverty and strong local dependence on provisioning ecosystem services for livelihoods. We develop a method to extrapolate results from a previously published village scale ecosystem services assessment to a higher administrative level, relevant for land use decision making. The method combines remote sensing (using a hybrid classification method) and interviews with community members. The resulting landscape scale maps show the spatial distribution of five different livelihood benefits (nutritional diversity, income, insurance/saving, material assets and energy, and crops for consumption) that illustrate the strong multifunctionality of the Sahelian landscapes. The maps highlight the importance of a diverse set of sub-units of the landscape in supporting Sahelian livelihoods. We see a large potential in using the resulting type of livelihood benefit maps for guiding future land use decisions in the Sahel. PMID:29389965

  7. Mapping regional livelihood benefits from local ecosystem services assessments in rural Sahel.

    Directory of Open Access Journals (Sweden)

    Katja Malmborg

    Full Text Available Most current approaches to landscape scale ecosystem service assessments rely on detailed secondary data. This type of data is seldom available in regions with high levels of poverty and strong local dependence on provisioning ecosystem services for livelihoods. We develop a method to extrapolate results from a previously published village scale ecosystem services assessment to a higher administrative level, relevant for land use decision making. The method combines remote sensing (using a hybrid classification method and interviews with community members. The resulting landscape scale maps show the spatial distribution of five different livelihood benefits (nutritional diversity, income, insurance/saving, material assets and energy, and crops for consumption that illustrate the strong multifunctionality of the Sahelian landscapes. The maps highlight the importance of a diverse set of sub-units of the landscape in supporting Sahelian livelihoods. We see a large potential in using the resulting type of livelihood benefit maps for guiding future land use decisions in the Sahel.

  8. Inference for Local Distributions at High Sampling Frequencies: A Bootstrap Approach

    DEFF Research Database (Denmark)

    Hounyo, Ulrich; Varneskov, Rasmus T.

    of "large" jumps. Our locally dependent wild bootstrap (LDWB) accommodate issues related to the stochastic scale and jumps as well as account for a special block-wise dependence structure induced by sampling errors. We show that the LDWB replicates first and second-order limit theory from the usual...... empirical process and the stochastic scale estimate, respectively, as well as an asymptotic bias. Moreover, we design the LDWB sufficiently general to establish asymptotic equivalence between it and and a nonparametric local block bootstrap, also introduced here, up to second-order distribution theory....... Finally, we introduce LDWB-aided Kolmogorov-Smirnov tests for local Gaussianity as well as local von-Mises statistics, with and without bootstrap inference, and establish their asymptotic validity using the second-order distribution theory. The finite sample performance of CLT and LDWB-aided local...

  9. Local discrepancies in continental scale biomass maps: a case study over forested and non-forested landscapes in Maryland, USA

    Science.gov (United States)

    Wenli Huang; Anu Swatantran; Kristofer Johnson; Laura Duncanson; Hao Tang; Jarlath O' Neil Dunne; George Hurtt; Ralph Dubayah

    2015-01-01

    Continental-scale aboveground biomass maps are increasingly available, but their estimates vary widely, particularly at high resolution. A comprehensive understanding of map discrepancies is required to improve their effectiveness in carbon accounting and local decision-making. To this end, we compare four continental-scale maps with a recent high-resolution lidar-...

  10. Creation Greenhouse Environment Map Using Localization of Edge of Cultivation Platforms Based on Stereo Vision

    Directory of Open Access Journals (Sweden)

    A Nasiri

    2017-10-01

    Full Text Available Introduction Stereo vision means the capability of extracting the depth based on analysis of two images taken from different angles of one scene. The result of stereo vision is a collection of three-dimensional points which describes the details of scene proportional to the resolution of the obtained images. Vehicle automatic steering and crop growth monitoring are two important operations in agricultural precision. The essential aspects of an automated steering are position and orientation of the agricultural equipment in relation to crop row, detection of obstacles and design of path planning between the crop rows. The developed map can provide this information in the real time. Machine vision has the capabilities to perform these tasks in order to execute some operations such as cultivation, spraying and harvesting. In greenhouse environment, it is possible to develop a map and perform an automatic control by detecting and localizing the cultivation platforms as the main moving obstacle. The current work was performed to meet a method based on the stereo vision for detecting and localizing platforms, and then, providing a two-dimensional map for cultivation platforms in the greenhouse environment. Materials and Methods In this research, two webcams, made by Microsoft Corporation with the resolution of 960×544, are connected to the computer via USB2 in order to produce a stereo parallel camera. Due to the structure of cultivation platforms, the number of points in the point cloud will be decreased by extracting the only upper and lower edges of the platform. The proposed method in this work aims at extracting the edges based on depth discontinuous features in the region of platform edge. By getting the disparity image of the platform edges from the rectified stereo images and translating its data to 3D-space, the point cloud model of the environments is constructed. Then by projecting the points to XZ plane and putting local maps together

  11. Using NDVI and guided sampling to develop yield prediction maps of processing tomato crop

    Energy Technology Data Exchange (ETDEWEB)

    Fortes, A.; Henar Prieto, M. del; García-Martín, A.; Córdoba, A.; Martínez, L.; Campillo, C.

    2015-07-01

    The use of yield prediction maps is an important tool for the delineation of within-field management zones. Vegetation indices based on crop reflectance are of potential use in the attainment of this objective. There are different types of vegetation indices based on crop reflectance, the most commonly used of which is the NDVI (normalized difference vegetation index). NDVI values are reported to have good correlation with several vegetation parameters including the ability to predict yield. The field research was conducted in two commercial farms of processing tomato crop, Cantillana and Enviciados. An NDVI prediction map developed through ordinary kriging technique was used for guided sampling of processing tomato yield. Yield was studied and related with NDVI, and finally a prediction map of crop yield for the entire plot was generated using two geostatistical methodologies (ordinary and regression kriging). Finally, a comparison was made between the yield obtained at validation points and the yield values according to the prediction maps. The most precise yield maps were obtained with the regression kriging methodology with RRMSE values of 14% and 17% in Cantillana and Enviciados, respectively, using the NDVI as predictor. The coefficient of correlation between NDVI and yield was correlated in the point samples taken in the two locations, with values of 0.71 and 0.67 in Cantillana and Enviciados, respectively. The results suggest that the use of a massive sampling parameter such as NDVI is a good indicator of the distribution of within-field yield variation. (Author)

  12. Visual simultaneous localization and mapping (VSLAM) methods applied to indoor 3D topographical and radiological mapping in real-time

    International Nuclear Information System (INIS)

    Hautot, F.; Dubart, P.; Chagneau, B.; Bacri, C.O.; Abou-Khalil, R.

    2017-01-01

    New developments in the field of robotics and computer vision enable to merge sensors to allow fast real-time localization of radiological measurements in the space/volume with near real-time radioactive sources identification and characterization. These capabilities lead nuclear investigations to a more efficient way for operators' dosimetry evaluation, intervention scenarios and risks mitigation and simulations, such as accidents in unknown potentially contaminated areas or during dismantling operations. This paper will present new progresses in merging RGB-D camera based on SLAM (Simultaneous Localization and Mapping) systems and nuclear measurement in motion methods in order to detect, locate, and evaluate the activity of radioactive sources in 3-dimensions

  13. Influence of neighbourhood information on 'Local Climate Zone' mapping in heterogeneous cities

    Science.gov (United States)

    Verdonck, Marie-Leen; Okujeni, Akpona; van der Linden, Sebastian; Demuzere, Matthias; De Wulf, Robert; Van Coillie, Frieke

    2017-10-01

    Local climate zone (LCZ) mapping is an emerging field in urban climate research. LCZs potentially provide an objective framework to assess urban form and function worldwide. The scheme is currently being used to globally map LCZs as a part of the World Urban Database and Access Portal Tools (WUDAPT) initiative. So far, most of the LCZ maps lack proper quantitative assessment, challenging the generic character of the WUDAPT workflow. Using the standard method introduced by the WUDAPT community difficulties arose concerning the built zones due to high levels of heterogeneity. To overcome this problem a contextual classifier is adopted in the mapping process. This paper quantitatively assesses the influence of neighbourhood information on the LCZ mapping result of three cities in Belgium: Antwerp, Brussels and Ghent. Overall accuracies for the maps were respectively 85.7 ± 0.5, 79.6 ± 0.9, 90.2 ± 0.4%. The approach presented here results in overall accuracies of 93.6 ± 0.2, 92.6 ± 0.3 and 95.6 ± 0.3% for Antwerp, Brussels and Ghent. The results thus indicate a positive influence of neighbourhood information for all study areas with an increase in overall accuracies of 7.9, 13.0 and 5.4%. This paper reaches two main conclusions. Firstly, evidence was introduced on the relevance of a quantitative accuracy assessment in LCZ mapping, showing that the accuracies reported in previous papers are not easily achieved. Secondly, the method presented in this paper proves to be highly effective in Belgian cities, and given its open character shows promise for application in other heterogeneous cities worldwide.

  14. Fast mapping of the local environment of an autonomous mobile robot

    International Nuclear Information System (INIS)

    Fanton, Herve

    1989-01-01

    The construction of a map of the local world for the navigation of an autonomous mobile robot leads to the following problem: how to extract among the sensor data information accurate an reliable enough to plan a path, in a way that enables a reasonable displacement speed. Choice has been made not to tele-operate the vehicle nor to design any custom architecture. So the only way to match the computational cost is to look for the most efficient sensor-algorithms-architecture combination. A good solution is described in this study, using a laser range-finder, a grid model of the world and both SIMD and MIMD parallel processors. A short review of some possible approaches is made first; the mapping algorithms are then described as also the parallel implementations with the corresponding speedup and efficiency factors. (author) [fr

  15. Kalman/Map Filtering-Aided Fast Normalized Cross Correlation-Based Wi-Fi Fingerprinting Location Sensing

    Directory of Open Access Journals (Sweden)

    Yongliang Sun

    2013-11-01

    Full Text Available A Kalman/map filtering (KMF-aided fast normalized cross correlation (FNCC-based Wi-Fi fingerprinting location sensing system is proposed in this paper. Compared with conventional neighbor selection algorithms that calculate localization results with received signal strength (RSS mean samples, the proposed FNCC algorithm makes use of all the on-line RSS samples and reference point RSS variations to achieve higher fingerprinting accuracy. The FNCC computes efficiently while maintaining the same accuracy as the basic normalized cross correlation. Additionally, a KMF is also proposed to process fingerprinting localization results. It employs a new map matching algorithm to nonlinearize the linear location prediction process of Kalman filtering (KF that takes advantage of spatial proximities of consecutive localization results. With a calibration model integrated into an indoor map, the map matching algorithm corrects unreasonable prediction locations of the KF according to the building interior structure. Thus, more accurate prediction locations are obtained. Using these locations, the KMF considerably improves fingerprinting algorithm performance. Experimental results demonstrate that the FNCC algorithm with reduced computational complexity outperforms other neighbor selection algorithms and the KMF effectively improves location sensing accuracy by using indoor map information and spatial proximities of consecutive localization results.

  16. Kalman/Map filtering-aided fast normalized cross correlation-based Wi-Fi fingerprinting location sensing.

    Science.gov (United States)

    Sun, Yongliang; Xu, Yubin; Li, Cheng; Ma, Lin

    2013-11-13

    A Kalman/map filtering (KMF)-aided fast normalized cross correlation (FNCC)-based Wi-Fi fingerprinting location sensing system is proposed in this paper. Compared with conventional neighbor selection algorithms that calculate localization results with received signal strength (RSS) mean samples, the proposed FNCC algorithm makes use of all the on-line RSS samples and reference point RSS variations to achieve higher fingerprinting accuracy. The FNCC computes efficiently while maintaining the same accuracy as the basic normalized cross correlation. Additionally, a KMF is also proposed to process fingerprinting localization results. It employs a new map matching algorithm to nonlinearize the linear location prediction process of Kalman filtering (KF) that takes advantage of spatial proximities of consecutive localization results. With a calibration model integrated into an indoor map, the map matching algorithm corrects unreasonable prediction locations of the KF according to the building interior structure. Thus, more accurate prediction locations are obtained. Using these locations, the KMF considerably improves fingerprinting algorithm performance. Experimental results demonstrate that the FNCC algorithm with reduced computational complexity outperforms other neighbor selection algorithms and the KMF effectively improves location sensing accuracy by using indoor map information and spatial proximities of consecutive localization results.

  17. A review of feature detection and match algorithms for localization and mapping

    Science.gov (United States)

    Li, Shimiao

    2017-09-01

    Localization and mapping is an essential ability of a robot to keep track of its own location in an unknown environment. Among existing methods for this purpose, vision-based methods are more effective solutions for being accurate, inexpensive and versatile. Vision-based methods can generally be categorized as feature-based approaches and appearance-based approaches. The feature-based approaches prove higher performance in textured scenarios. However, their performance depend highly on the applied feature-detection algorithms. In this paper, we surveyed algorithms for feature detection, which is an essential step in achieving vision-based localization and mapping. In this pater, we present mathematical models of the algorithms one after another. To compare the performances of the algorithms, we conducted a series of experiments on their accuracy, speed, scale invariance and rotation invariance. The results of the experiments showed that ORB is the fastest algorithm in detecting and matching features, the speed of which is more than 10 times that of SURF and approximately 40 times that of SIFT. And SIFT, although with no advantage in terms of speed, shows the most correct matching pairs and proves its accuracy.

  18. Accuracy assessment of the National Forest Inventory map of Mexico: sampling designs and the fuzzy characterization of landscapes

    Directory of Open Access Journals (Sweden)

    Stéphane Couturier

    2009-10-01

    Full Text Available There is no record so far in the literature of a comprehensive method to assess the accuracy of regional scale Land Cover/ Land Use (LCLU maps in the sub-tropical belt. The elevated biodiversity and the presence of highly fragmented classes hamper the use of sampling designs commonly employed in previous assessments of mainly temperate zones. A sampling design for assessing the accuracy of the Mexican National Forest Inventory (NFI map at community level is presented. A pilot study was conducted on the Cuitzeo Lake watershed region covering 400 000 ha of the 2000 Landsat-derived map. Various sampling designs were tested in order to find a trade-off between operational costs, a good spatial distribution of the sample and the inclusion of all scarcely distributed classes (‘rare classes’. A two-stage sampling design where the selection of Primary Sampling Units (PSU was done under separate schemes for commonly and scarcely distributed classes, showed best characteristics. A total of 2 023 punctual secondary sampling units were verified against their NFI map label. Issues regarding the assessment strategy and trends of class confusions are devised.

  19. Quantal bookkeeping of samples and locality

    International Nuclear Information System (INIS)

    Groenewold, H.J.

    1983-01-01

    The skeptical pruned ensemble interpretation of quantal measurements is described in the conventional representation and in an equivalent hedge-hog representation. (A symmetric hedge-hog is displayed by a spiny array of Hilbert projectors.) A fundamental problem of any individual interpretation is the distinction in the formalism of individual samples and their mutual independence. In the formal hedge-hog bookkeeping an auxiliary hedge-hog hypothesis is proposed, which associates separate real samples of quantal ensembles with separate fictions hedge-hogs. In accordance with its private unobservable hedge-hog each sample has so to speak to every potential observable question its own definite potential answer in store. The statistical distribution of the answers of the various samples to all questions is represented by the ensemble operator, which can only be attributed to the entire ensemble as a whole. Observable answers can be obtained from an individual real sample only one at a time. In this fictitous finer grained model the hedge-hogs metaphorically represent a kind of individual memory of the corresponding samples. The principle of mutual kinematical and dynamical independence of samples as well as the principle of locality in retarded correlation is satisfied. This has to be paid for by indefinite statistics of the hedge-hog distribution in the ensemble. Even if the hedge-hog model is afterwards thrown away as an untestable fake, the logical compatibility of these two fundamental principles (whatever their significance may be) with standard quantum mechanics holds firm. The physical compatibility remains an open question. (orig.)

  20. Integrating field sampling, geostatistics and remote sensing to map wetland vegetation in the Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    J. Arieira

    2011-03-01

    Full Text Available Development of efficient methodologies for mapping wetland vegetation is of key importance to wetland conservation. Here we propose the integration of a number of statistical techniques, in particular cluster analysis, universal kriging and error propagation modelling, to integrate observations from remote sensing and field sampling for mapping vegetation communities and estimating uncertainty. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relationship between remotely sensed data and vegetation patterns, captured in four factorial axes, were described using multiple linear regression models. There were then used in a universal kriging procedure to reduce the mapping uncertainty. Cross-validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty derived from Monte Carlo simulations revealed significant spatial variation in classification, but this had little impact on the proportion and arrangement of the communities observed. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by including a larger number of digital images as explanatory variables in the model. Comparison of the resulting plant community map with a flood duration map, revealed that flooding duration is an important driver of vegetation zonation. This mapping approach is able to integrate field point data and high-resolution remote-sensing images, providing a new basis to map wetland vegetation and allow its future application in habitat management, conservation assessment and long-term ecological monitoring in wetland

  1. Elemental mapping of large samples by external ion beam analysis with sub-millimeter resolution and its applications

    Science.gov (United States)

    Silva, T. F.; Rodrigues, C. L.; Added, N.; Rizzutto, M. A.; Tabacniks, M. H.; Mangiarotti, A.; Curado, J. F.; Aguirre, F. R.; Aguero, N. F.; Allegro, P. R. P.; Campos, P. H. O. V.; Restrepo, J. M.; Trindade, G. F.; Antonio, M. R.; Assis, R. F.; Leite, A. R.

    2018-05-01

    The elemental mapping of large areas using ion beam techniques is a desired capability for several scientific communities, involved on topics ranging from geoscience to cultural heritage. Usually, the constraints for large-area mapping are not met in setups employing micro- and nano-probes implemented all over the world. A novel setup for mapping large sized samples in an external beam was recently built at the University of São Paulo employing a broad MeV-proton probe with sub-millimeter dimension, coupled to a high-precision large range XYZ robotic stage (60 cm range in all axis and precision of 5 μ m ensured by optical sensors). An important issue on large area mapping is how to deal with the irregularities of the sample's surface, that may introduce artifacts in the images due to the variation of the measuring conditions. In our setup, we implemented an automatic system based on machine vision to correct the position of the sample to compensate for its surface irregularities. As an additional benefit, a 3D digital reconstruction of the scanned surface can also be obtained. Using this new and unique setup, we have produced large-area elemental maps of ceramics, stones, fossils, and other sort of samples.

  2. Assessment and visualization of uncertainty for countrywide soil organic matter map of Hungary using local entropy

    Science.gov (United States)

    Szatmári, Gábor; Pásztor, László

    2016-04-01

    Uncertainty is a general term expressing our imperfect knowledge in describing an environmental process and we are aware of it (Bárdossy and Fodor, 2004). Sampling, laboratory measurements, models and so on are subject to uncertainty. Effective quantification and visualization of uncertainty would be indispensable to stakeholders (e.g. policy makers, society). Soil related features and their spatial models should be stressfully targeted to uncertainty assessment because their inferences are further used in modelling and decision making process. The aim of our present study was to assess and effectively visualize the local uncertainty of the countrywide soil organic matter (SOM) spatial distribution model of Hungary using geostatistical tools and concepts. The Hungarian Soil Information and Monitoring System's SOM data (approximately 1,200 observations) and environmental related, spatially exhaustive secondary information (i.e. digital elevation model, climatic maps, MODIS satellite images and geological map) were used to model the countrywide SOM spatial distribution by regression kriging. It would be common to use the calculated estimation (or kriging) variance as a measure of uncertainty, however the normality and homoscedasticity hypotheses have to be refused according to our preliminary analysis on the data. Therefore, a normal score transformation and a sequential stochastic simulation approach was introduced to be able to model and assess the local uncertainty. Five hundred equally probable realizations (i.e. stochastic images) were generated. The number of the stochastic images is fairly enough to provide a model of uncertainty at each location, which is a complete description of uncertainty in geostatistics (Deutsch and Journel, 1998). Furthermore, these models can be applied e.g. to contour the probability of any events, which can be regarded as goal oriented digital soil maps and are of interest for agricultural management and decision making as well. A

  3. Exploring local risk managers' use of flood hazard maps for risk communication purposes in Baden-Württemberg

    Directory of Open Access Journals (Sweden)

    S. Kjellgren

    2013-07-01

    Full Text Available In response to the EU Floods Directive (2007/60/EC, flood hazard maps are currently produced all over Europe, reflecting a wider shift in focus from "flood protection" to "risk management", for which not only public authorities but also populations at risk are seen as responsible. By providing a visual image of the foreseen consequences of flooding, flood hazard maps can enhance people's knowledge about flood risk, making them more capable of an adequate response. Current literature, however, questions the maps' awareness raising capacity, arguing that their content and design are rarely adjusted to laypeople's needs. This paper wants to complement this perspective with a focus on risk communication by studying how these tools are disseminated and marketed to the public in the first place. Judging from communication theory, simply making hazard maps publicly available is unlikely to lead to attitudinal or behavioral effects, since this typically requires two-way communication and material or symbolic incentives. Consequently, it is relevant to investigate whether and how local risk managers, who are well positioned to interact with the local population, make use of flood hazard maps for risk communication purposes. A qualitative case study of this issue in the German state of Baden-Württemberg suggests that many municipalities lack a clear strategy for using this new information tool for hazard and risk communication. Four barriers in this regard are identified: perceived disinterest/sufficient awareness on behalf of the population at risk; unwillingness to cause worry or distress; lack of skills and resources; and insufficient support. These barriers are important to address – in research as well as in practice – since it is only if flood hazard maps are used to enhance local knowledge resources that they can be expected to contribute to social capacity building.

  4. Exploring local risk managers' use of flood hazard maps for risk communication purposes in Baden-Württemberg

    Science.gov (United States)

    Kjellgren, S.

    2013-07-01

    In response to the EU Floods Directive (2007/60/EC), flood hazard maps are currently produced all over Europe, reflecting a wider shift in focus from "flood protection" to "risk management", for which not only public authorities but also populations at risk are seen as responsible. By providing a visual image of the foreseen consequences of flooding, flood hazard maps can enhance people's knowledge about flood risk, making them more capable of an adequate response. Current literature, however, questions the maps' awareness raising capacity, arguing that their content and design are rarely adjusted to laypeople's needs. This paper wants to complement this perspective with a focus on risk communication by studying how these tools are disseminated and marketed to the public in the first place. Judging from communication theory, simply making hazard maps publicly available is unlikely to lead to attitudinal or behavioral effects, since this typically requires two-way communication and material or symbolic incentives. Consequently, it is relevant to investigate whether and how local risk managers, who are well positioned to interact with the local population, make use of flood hazard maps for risk communication purposes. A qualitative case study of this issue in the German state of Baden-Württemberg suggests that many municipalities lack a clear strategy for using this new information tool for hazard and risk communication. Four barriers in this regard are identified: perceived disinterest/sufficient awareness on behalf of the population at risk; unwillingness to cause worry or distress; lack of skills and resources; and insufficient support. These barriers are important to address - in research as well as in practice - since it is only if flood hazard maps are used to enhance local knowledge resources that they can be expected to contribute to social capacity building.

  5. Mapping local knowledge of hazards to inform research, practice and policy in the Americas

    International Nuclear Information System (INIS)

    Coles, Ashley; Eosco, Gina; Norton, Todd; Ruiz, Jorge; Tate, Eric; Weathers, Melinda

    2011-01-01

    Hazards are fundamentally understood and experienced spatially; therefore, it is not surprising that hazards research, management, communication, and policy have relied heavily on spatial representations using geomatics tools such as remote sensing and geographic information systems (GIS). As powerful and useful as these tools have been, they tend to privilege the collection and utilization of quantifiable data at the expense of qualitative data (e.g., experiential local knowledge). Local knowledge has been increasingly used both to challenge and to supplement mapping strategies, although less so in the realm of hazards than in other areas such as natural resource management. In this paper, we propose a unique framework for taking these approaches one-step further through the development of a knowledge management system that integrates local knowledge of hazards with spatial visualization tools. First, we discuss relevant literature related to current tools and practices for visualizing hazard information. Next we propose a methodology for mapping mental models of individuals. Finally, we discuss the potential applications of such a framework for hazards research, practice, and policy, as well as discuss the challenges associated with this framework.

  6. Defining Mapping Mashups with BioXMash

    Directory of Open Access Journals (Sweden)

    Hunt Ela

    2007-12-01

    Full Text Available We present a novel approach to XML data integration which allows a biologist to select data from a large XML file repository, add it to a genome map, and produce a mapping mashup showing integrated data in map context. This approach can be used to produce contextual views of arbitrary XML data which relates to objects shown on a map. A biologist using BioXMash searches in XML tags, and is guided by XML path data availability, shown as the number of values reachable via a path, in both global, genome-wide, and local, per-gene, context. Then she examines sample values in an area of interest on the map. If required, the resulting data is dumped to files, for subsequent analysis.

  7. Unified framework for recognition, localization and mapping using wearable cameras.

    Science.gov (United States)

    Vázquez-Martín, Ricardo; Bandera, Antonio

    2012-08-01

    Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be

  8. Using Environmental Variables for Studying of the Quality of Sampling in Soil Mapping

    OpenAIRE

    A. Jafari; Norair Toomanian; R. Taghizadeh Mehrjerdi

    2016-01-01

    Introduction: Methods of soil survey are generally empirical and based on the mental development of the surveyor, correlating soil with underlying geology, landforms, vegetation and air-photo interpretation. Since there are no statistical criteria for traditional soil sampling; this may lead to bias in the areas being sampled. In digital soil mapping, soil samples may be used to elaborate quantitative relationships or models between soil attributes and soil covariates. Because the relationshi...

  9. Reliability of different sampling densities for estimating and mapping lichen diversity in biomonitoring studies

    International Nuclear Information System (INIS)

    Ferretti, M.; Brambilla, E.; Brunialti, G.; Fornasier, F.; Mazzali, C.; Giordani, P.; Nimis, P.L.

    2004-01-01

    Sampling requirements related to lichen biomonitoring include optimal sampling density for obtaining precise and unbiased estimates of population parameters and maps of known reliability. Two available datasets on a sub-national scale in Italy were used to determine a cost-effective sampling density to be adopted in medium-to-large-scale biomonitoring studies. As expected, the relative error in the mean Lichen Biodiversity (Italian acronym: BL) values and the error associated with the interpolation of BL values for (unmeasured) grid cells increased as the sampling density decreased. However, the increase in size of the error was not linear and even a considerable reduction (up to 50%) in the original sampling effort led to a far smaller increase in errors in the mean estimates (<6%) and in mapping (<18%) as compared with the original sampling densities. A reduction in the sampling effort can result in considerable savings of resources, which can then be used for a more detailed investigation of potentially problematic areas. It is, however, necessary to decide the acceptable level of precision at the design stage of the investigation, so as to select the proper sampling density. - An acceptable level of precision must be decided before determining a sampling design

  10. AMCO Scribe Sampling Data Map Service, Oakland CA, 2017, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map service contains a single layer: Groundwater Samples. The layer draws at all scales. Full FGDC metadata for the layer may be found by clicking the layer...

  11. Feature Point Extraction from the Local Frequency Map of an Image

    Directory of Open Access Journals (Sweden)

    Jesmin Khan

    2012-01-01

    Full Text Available We propose a novel technique for detecting rotation- and scale-invariant interest points from the local frequency representation of an image. Local or instantaneous frequency is the spatial derivative of the local phase, where the local phase of any signal can be found from its Hilbert transform. Local frequency estimation can detect edge, ridge, corner, and texture information at the same time, and it shows high values at those dominant features of an image. For each pixel, we select an appropriate width of the window for computing the derivative of the phase. In order to select the width of the window for any given pixel, we make use of the measure of the extent to which the phases, in the neighborhood of that pixel, are in the same direction. The local frequency map, thus obtained, is then thresholded by employing a global thresholding approach to detect the interest or feature points. Repeatability rate, a performance evaluation criterion for an interest point detector, is used to check the geometric stability of the proposed method under different transformations. We present simulation results of the detection of feature points from image utilizing the suggested technique and compare the proposed method with five existing approaches that yield good results. The results prove the efficacy of the proposed feature point detection algorithm. Moreover, in terms of repeatability rate; the results show that the performance of the proposed method with respect to different aspect is compatible with the existing methods.

  12. CT in the staging of bronchogenic carcinoma: Analysis by correlative lymph node mapping and sampling

    International Nuclear Information System (INIS)

    McLoud, T.C.; Woldenberg, R.; Mathisen, D.J.; Grillo, H.C.; Bourgoulin, P.M.; Shepard, J.O.; Moore, E.H.

    1987-01-01

    Although previous studies have evaluated the accuracy of CT in staging the mediastinum in bronchogenic carcinoma, none has determined the sensitivity and specificity of CT in the assessment of individual lymph node groups by correlative nodal sampling at surgery. CT scans were performed on 84 patients with bronchogenic carcinoma. Abnormal nodes (≥ 1 cm) were localized according to the ATS classification of regional lymph node mapping. Seventy-nine patients had mediastinoscopy and 64 patients underwent thoracotomy. In each case, biopsies of lymph node groups 2R, 4R, 2L, 4L (paratracheal), 7 (subcarinal), and 5 (aorticopulmonary) were performed on the appropriate side. Hilar nodes (10R and 11R, 10L and 11L) were resected with the surgical specimen. A total of 292 nodes were sampled. Overall sensitivity for all lymph node groups was 40%, and specificity, 81%. Sensitivity was highest for the 4R (paratracheal) group (82%) and lowest for the subcarinal area (20%). Specificity ranged from 71% for 11R nodes (right hilar) to 94% for 10L (left peribronchial). The positive predictive value was 34%, and the negative predictive value, 84%. This study suggests that the more optimistic results previously reported may have resulted from lack of correlation of individual lymph node groups identified on CT with those sampled at surgery

  13. Self-Organizing Maps Neural Networks Applied to the Classification of Ethanol Samples According to the Region of Commercialization

    Directory of Open Access Journals (Sweden)

    Aline Regina Walkoff

    2017-10-01

    Full Text Available Physical-chemical analysis data were collected, from 998 ethanol samples of automotive ethanol commercialized in the northern, midwestern and eastern regions of the state of Paraná. The data presented self-organizing maps (SOM neural networks, which classified them according to those regions. The self-organizing maps best configuration had a 45 x 45 topology and 5000 training epochs, with a final learning rate of 6.7x10-4, a final neighborhood relationship of 3x10-2 and a mean quantization error of 2x10-2. This neural network provided a topological map depicting three separated groups, each one corresponding to samples of a same region of commercialization. Four maps of weights, one for each parameter, were presented. The network established the pH was the most important variable for classification and electrical conductivity the least one. The self-organizing maps application allowed the segmentation of alcohol samples, therefore identifying them according to the region of commercialization. DOI: http://dx.doi.org/10.17807/orbital.v9i4.982

  14. The Metacognitive Anger Processing (MAP) Scale - Validation in a Mixed Clinical and a Forensic In-Patient Sample

    DEFF Research Database (Denmark)

    Moeller, Stine Bjerrum; Bech, Per

    2018-01-01

    BACKGROUND: The metacognitive approach by Wells and colleagues has gained empirical support with a broad range of symptoms. The Metacognitive Anger Processing (MAP) scale was developed to provide a metacognitive measure on anger (Moeller, 2016). In the preliminary validation, three components were...... identified (positive beliefs, negative beliefs and rumination) to be positively correlated with the anger. AIMS: To validate the MAP in a sample of mixed clinical patients (n = 88) and a sample of male forensic patients (n = 54). METHOD: The MAP was administered together with measures of metacognition, anger......, rumination, anxiety and depressive symptoms. RESULTS: The MAP showed acceptable scalability and excellent reliability. Convergent validity was evidenced using the general metacognitive measure (MCQ-30), and concurrent validity was supported using two different anger measures (STAXI-2 and NAS). CONCLUSIONS...

  15. GIS and local knowledge in disaster management: a case study of flood risk mapping in Viet Nam.

    Science.gov (United States)

    Tran, Phong; Shaw, Rajib; Chantry, Guillaume; Norton, John

    2009-03-01

    Linking community knowledge with modern techniques to record and analyse risk related data is one way of engaging and mobilising community capacity. This paper discusses the use of the Geographic Information System (GIS) at the local level and the need for integrating modern technology and indigenous knowledge into disaster management. It suggests a way to mobilise available human and technical resources in order to strengthen a good partnership between local communities and local and national institutions. The paper also analyses the current vulnerability of two communes by correlating hazard risk and loss/damage caused by disasters and the contribution that domestic risk maps in the community can make to reduce this risk. The disadvantages, advantages and lessons learned from the GIS flood risk mapping project are presented through the case study of the Quang Tho Commune in Thua Thien Hue province, central Viet Nam.

  16. Children's active free play in local neighborhoods: a behavioral mapping study.

    Science.gov (United States)

    Veitch, J; Salmon, J; Ball, K

    2008-10-01

    Many Australian children are more sedentary than they should be, and almost one in five are currently overweight or obese. Some children may face difficulties finding opportunities to be active, having poor access to safe public open spaces or having low independent mobility limiting their access to places to play. This study aimed to examine children's access to places in their neighborhood for active free play and how these vary by age, sex and socioeconomic status (SES). Behavioral maps of the local neighborhood were completed by children (8-12 years) from five primary schools across different areas of Melbourne. Children living in low SES outer-urban neighborhoods had to travel greater distances to access local parks compared with those in inner-urban mid and high SES areas. One-third (32%) of children reported an independent mobility range of <100 m from home. In conclusion, for some children opportunities to engage in active free play in the local neighborhood may be limited due to lack of parks in close proximity to home and restricted independent mobility. It is important to collaborate with local governments, urban planners and community groups to improve access to neighborhood parks and to promote a sense of neighborhood safety.

  17. Soil geohazard mapping for improved asset management of UK local roads

    Science.gov (United States)

    Pritchard, O. G.; Hallett, S. H.; Farewell, T. S.

    2015-09-01

    Unclassified roads comprise 60 % of the road network in the United Kingdom (UK). The resilience of this locally important network is declining. It is considered by the Institution of Civil Engineers to be "at risk" and is ranked 26th in the world. Many factors contribute to the degradation and ultimate failure of particular road sections. However, several UK local authorities have identified that in drought conditions, road sections founded upon shrink-swell susceptible clay soils undergo significant deterioration compared with sections on non-susceptible soils. This arises from the local road network having little, if any, structural foundations. Consequently, droughts in East Anglia have resulted in millions of pounds of damage, leading authorities to seek emergency governmental funding. This paper assesses the use of soil-related geohazard assessments in providing soil-informed maintenance strategies for the asset management of the locally important road network of the UK. A case study draws upon the UK administrative county of Lincolnshire, where road assessment data have been analysed against mapped clay-subsidence risk. This reveals a statistically significant relationship between road condition and susceptible clay soils. Furthermore, incorporation of UKCP09 future climate projections within the geohazard models has highlighted roads likely to be at future risk of clay-related subsidence.

  18. Local Dynamic Map als modulares Software Framework für Fahrerassistenzsysteme

    Science.gov (United States)

    Reisdorf, P.; Auerswald, A.; Wanielik, G.

    2015-11-01

    Moderne Fahrerassistenzsysteme basieren auf der Verarbeitung von Informationen, welche durch die Umfeldwahrnehmung mit unterschiedlicher Sensorik erfolgt. Neben den Informationen aus dem eigenen Fahrzeug ergeben sich durch unterschiedliche Kommunikationsmöglichkeiten (Car2Car, Car2X,...) erweiterte Umfeldwahrnehmungen (siehe Abb. 1). Diese Daten gilt es aufbereitet und zielorientiert einer Anwendung zur Verfügung zu stellen, was mit Hilfe einer Local Dynamic Map (LDM) erfüllt werden kann. Die vorliegende Veröffentlichung beschreibt den Aufbau, Verwendungszweck und Eigenschaften einer entwickelten LDM und geht auf einige Applikationen ein, die mit Hilfe dieser realisiert wurden.

  19. Large area synchrotron X-ray fluorescence mapping of biological samples

    International Nuclear Information System (INIS)

    Kempson, I.; Thierry, B.; Smith, E.; Gao, M.; De Jonge, M.

    2014-01-01

    Large area mapping of inorganic material in biological samples has suffered severely from prohibitively long acquisition times. With the advent of new detector technology we can now generate statistically relevant information for studying cell populations, inter-variability and bioinorganic chemistry in large specimen. We have been implementing ultrafast synchrotron-based XRF mapping afforded by the MAIA detector for large area mapping of biological material. For example, a 2.5 million pixel map can be acquired in 3 hours, compared to a typical synchrotron XRF set-up needing over 1 month of uninterrupted beamtime. Of particular focus to us is the fate of metals and nanoparticles in cells, 3D tissue models and animal tissues. The large area scanning has for the first time provided statistically significant information on sufficiently large numbers of cells to provide data on intercellular variability in uptake of nanoparticles. Techniques such as flow cytometry generally require analysis of thousands of cells for statistically meaningful comparison, due to the large degree of variability. Large area XRF now gives comparable information in a quantifiable manner. Furthermore, we can now image localised deposition of nanoparticles in tissues that would be highly improbable to 'find' by typical XRF imaging. In addition, the ultra fast nature also makes it viable to conduct 3D XRF tomography over large dimensions. This technology avails new opportunities in biomonitoring and understanding metal and nanoparticle fate ex-vivo. Following from this is extension to molecular imaging through specific anti-body targeted nanoparticles to label specific tissues and monitor cellular process or biological consequence

  20. Efficient Unbiased Rendering using Enlightened Local Path Sampling

    DEFF Research Database (Denmark)

    Kristensen, Anders Wang

    measurements, which are the solution to the adjoint light transport problem. The second is a representation of the distribution of radiance and importance in the scene. We also derive a new method of particle sampling, which is advantageous compared to existing methods. Together we call the resulting algorithm....... The downside to using these algorithms is that they can be slow to converge. Due to the nature of Monte Carlo methods, the results are random variables subject to variance. This manifests itself as noise in the images, which can only be reduced by generating more samples. The reason these methods are slow...... is because of a lack of eeffective methods of importance sampling. Most global illumination algorithms are based on local path sampling, which is essentially a recipe for constructing random walks. Using this procedure paths are built based on information given explicitly as part of scene description...

  1. Mapping Typical Urban LULC from Landsat Imagery without Training Samples or Self-Defined Parameters

    Directory of Open Access Journals (Sweden)

    Hui Li

    2017-07-01

    Full Text Available Land use/land cover (LULC change is one of the most important indicators in understanding the interactions between humans and the environment. Traditionally, when LULC maps are produced yearly, most existing remote-sensing methods have to collect ground reference data annually, as the classifiers have to be trained individually in each corresponding year. This study presented a novel strategy to map LULC classes without training samples or assigning parameters. First of all, several novel indices were carefully selected from the index pool, which were able to highlight certain LULC very well. Following this, a common unsupervised classifier was employed to extract the LULC from the associated index image without assigning thresholds. Finally, a supervised classification was implemented with samples automatically collected from the unsupervised classification outputs. Results illustrated that the proposed method could achieve satisfactory performance, reaching similar accuracies to traditional approaches. Findings of this study demonstrate that the proposed strategy is a simple and effective alternative to mapping urban LULC. With the proposed strategy, the budget and time required for remote-sensing data processing could be reduced dramatically.

  2. Additional Samples: Where They Should Be Located

    International Nuclear Information System (INIS)

    Pilger, G. G.; Costa, J. F. C. L.; Koppe, J. C.

    2001-01-01

    Information for mine planning requires to be close spaced, if compared to the grid used for exploration and resource assessment. The additional samples collected during quasimining usually are located in the same pattern of the original diamond drillholes net but closer spaced. This procedure is not the best in mathematical sense for selecting a location. The impact of an additional information to reduce the uncertainty about the parameter been modeled is not the same everywhere within the deposit. Some locations are more sensitive in reducing the local and global uncertainty than others. This study introduces a methodology to select additional sample locations based on stochastic simulation. The procedure takes into account data variability and their spatial location. Multiple equally probable models representing a geological attribute are generated via geostatistical simulation. These models share basically the same histogram and the same variogram obtained from the original data set. At each block belonging to the model a value is obtained from the n simulations and their combination allows one to access local variability. Variability is measured using an uncertainty index proposed. This index was used to map zones of high variability. A value extracted from a given simulation is added to the original data set from a zone identified as erratic in the previous maps. The process of adding samples and simulation is repeated and the benefit of the additional sample is evaluated. The benefit in terms of uncertainty reduction is measure locally and globally. The procedure showed to be robust and theoretically sound, mapping zones where the additional information is most beneficial. A case study in a coal mine using coal seam thickness illustrates the method

  3. A Novel Edge-Map Creation Approach for Highly Accurate Pupil Localization in Unconstrained Infrared Iris Images

    Directory of Open Access Journals (Sweden)

    Vineet Kumar

    2016-01-01

    Full Text Available Iris segmentation in the iris recognition systems is a challenging task under noncooperative environments. The iris segmentation is a process of detecting the pupil, iris’s outer boundary, and eyelids in the iris image. In this paper, we propose a pupil localization method for locating the pupils in the non-close-up and frontal-view iris images that are captured under near-infrared (NIR illuminations and contain the noise, such as specular and lighting reflection spots, eyeglasses, nonuniform illumination, low contrast, and occlusions by the eyelids, eyelashes, and eyebrow hair. In the proposed method, first, a novel edge-map is created from the iris image, which is based on combining the conventional thresholding and edge detection based segmentation techniques, and then, the general circular Hough transform (CHT is used to find the pupil circle parameters in the edge-map. Our main contribution in this research is a novel edge-map creation technique, which reduces the false edges drastically in the edge-map of the iris image and makes the pupil localization in the noisy NIR images more accurate, fast, robust, and simple. The proposed method was tested with three iris databases: CASIA-Iris-Thousand (version 4.0, CASIA-Iris-Lamp (version 3.0, and MMU (version 2.0. The average accuracy of the proposed method is 99.72% and average time cost per image is 0.727 sec.

  4. Sampling and Mapping Soil Erosion Cover Factor for Fort Richardson, Alaska. Integrating Stratification and an Up-Scaling Method

    National Research Council Canada - National Science Library

    Wang, Guangxing; Gertner, George; Anderson, Alan B; Howard, Heidi

    2006-01-01

    When a ground and vegetation cover factor related to soil erosion is mapped with the aid of remotely sensed data, a cost-efficient sample design to collect ground data and obtain an accurate map is required...

  5. Mapping the Local Density of Optical States of a Photonic Crystal with Single Quantum Dots

    DEFF Research Database (Denmark)

    Wang, Qin; Stobbe, Søren; Lodahl, Peter

    2011-01-01

    We use single self-assembled InGaAs quantum dots as internal probes to map the local density of optical states of photonic crystal membranes. The employed technique separates contributions from nonradiative recombination and spin-flip processes by properly accounting for the role of the exciton...... fine structure. We observe inhibition factors as high as 70 and compare our results to local density of optical states calculations available from the literature, thereby establishing a quantitative understanding of photon emission in photonic crystal membranes. © 2011 American Physical Society....

  6. Localization of canine brachycephaly using an across breed mapping approach.

    Directory of Open Access Journals (Sweden)

    Danika Bannasch

    2010-03-01

    Full Text Available The domestic dog, Canis familiaris, exhibits profound phenotypic diversity and is an ideal model organism for the genetic dissection of simple and complex traits. However, some of the most interesting phenotypes are fixed in particular breeds and are therefore less tractable to genetic analysis using classical segregation-based mapping approaches. We implemented an across breed mapping approach using a moderately dense SNP array, a low number of animals and breeds carefully selected for the phenotypes of interest to identify genetic variants responsible for breed-defining characteristics. Using a modest number of affected (10-30 and control (20-60 samples from multiple breeds, the correct chromosomal assignment was identified in a proof of concept experiment using three previously defined loci; hyperuricosuria, white spotting and chondrodysplasia. Genome-wide association was performed in a similar manner for one of the most striking morphological traits in dogs: brachycephalic head type. Although candidate gene approaches based on comparable phenotypes in mice and humans have been utilized for this trait, the causative gene has remained elusive using this method. Samples from nine affected breeds and thirteen control breeds identified strong genome-wide associations for brachycephalic head type on Cfa 1. Two independent datasets identified the same genomic region. Levels of relative heterozygosity in the associated region indicate that it has been subjected to a selective sweep, consistent with it being a breed defining morphological characteristic. Genotyping additional dogs in the region confirmed the association. To date, the genetic structure of dog breeds has primarily been exploited for genome wide association for segregating traits. These results demonstrate that non-segregating traits under strong selection are equally tractable to genetic analysis using small sample numbers.

  7. The Toggle Local Planner for sampling-based motion planning

    KAUST Repository

    Denny, Jory

    2012-05-01

    Sampling-based solutions to the motion planning problem, such as the probabilistic roadmap method (PRM), have become commonplace in robotics applications. These solutions are the norm as the dimensionality of the planning space grows, i.e., d > 5. An important primitive of these methods is the local planner, which is used for validation of simple paths between two configurations. The most common is the straight-line local planner which interpolates along the straight line between the two configurations. In this paper, we introduce a new local planner, Toggle Local Planner (Toggle LP), which extends local planning to a two-dimensional subspace of the overall planning space. If no path exists between the two configurations in the subspace, then Toggle LP is guaranteed to correctly return false. Intuitively, more connections could be found by Toggle LP than by the straight-line planner, resulting in better connected roadmaps. As shown in our results, this is the case, and additionally, the extra cost, in terms of time or storage, for Toggle LP is minimal. Additionally, our experimental analysis of the planner shows the benefit for a wide array of robots, with DOF as high as 70. © 2012 IEEE.

  8. Intermittent Contact Alternating Current Scanning Electrochemical Microscopy: A Method for Mapping Conductivities in Solid Li Ion Conducting Electrolyte Samples

    Energy Technology Data Exchange (ETDEWEB)

    Catarelli, Samantha Raisa; Lonsdale, Daniel [Uniscan Instruments Ltd., Macclesfield (United Kingdom); Cheng, Lei [Energy Storage and Distribution Resources Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Materials Sciences and Engineering Department, University of California Berkeley, Berkeley, CA (United States); Syzdek, Jaroslaw [Bio-Logic USA LLC, Knoxville, TN (United States); Doeff, Marca, E-mail: mmdoeff@lbl.gov [Energy Storage and Distribution Resources Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2016-03-31

    Intermittent contact alternating current scanning electrochemical microscopy (ic-ac-SECM) has been used to determine the electrochemical response to an ac signal of several types of materials. A conductive gold foil and insulating Teflon sheet were first used to demonstrate that the intermittent contact function allows the topography and conductivity to be mapped simultaneously and independently in a single experiment. Then, a dense pellet of an electronically insulating but Li ion conducting garnet phase, Al-substituted Li{sub 7}La{sub 3}Zr{sub 2}O{sub 12} (LLZO), was characterized using the same technique. The polycrystalline pellet was prepared by classical ceramic sintering techniques and was comprised of large (~150 μm) grains. Critical information regarding the contributions of grain and grain boundary resistances to the total conductivity of the garnet phase was lacking due to ambiguities in the impedance data. In contrast, the use of the ic-ac-SECM technique allowed spatially resolved information regarding local conductivities to be measured directly. Impedance mapping of the pellet showed that the grain boundary resistance, while generally higher than that of grains, varied considerably, revealing the complex nature of the LLZO sample.

  9. Incidence of Mycotoxins in Local and Branded Samples of Chocolates Marketed in Pakistan

    Directory of Open Access Journals (Sweden)

    Narjis Naz

    2017-01-01

    Full Text Available The present overview was intended to evaluate the degree of total aflatoxins and ochratoxin A contamination in different samples of bitter, dark, milk, and white chocolates marketed in Pakistan. For that exploration, two hundred (n=200 samples of chocolates, 100 branded and 100 local, were analyzed for mycotoxins profile by HPLC-FLD. The outcomes firmly sustained that the majority of the samples were contaminated with aflatoxins and ochratoxin A. The incidence of total aflatoxins and ochratoxin A in branded samples was 83% and 90%, whereas the local samples showed 91% and 97% contamination, respectively. The highest amount of total aflatoxins was found in branded dark chocolates, that is, 2.27 μg/kg, and maximum ochratoxin A level was detected white chocolates (2.06 μg/kg. On average, the local white chocolates and dark chocolates faced the highest level of total aflatoxins (3.35 μg/kg and ochratoxin A (3.48 μg/kg, respectively. The local samples of chocolates were more contaminated with mycotoxins as compared to branded ones accredited to the lack of quality control and quality assurance during the manufacturing as well as packing processes. In recent years, consumption of chocolate is rapidly increasing especially by young generation, so monitoring of mycotoxin occurrence in them is a matter of great concern and more studies are required to comprehend the production of mycotoxins in these products.

  10. Spatial resolution limits for the localization of noise sources using direct sound mapping

    DEFF Research Database (Denmark)

    Comesana, D. Fernandez; Holland, K. R.; Fernandez Grande, Efren

    2016-01-01

    the relationship between spatial resolution, noise level and geometry. The proposed expressions are validated via simulations and experiments. It is shown that particle velocity mapping yields better results for identifying closely spaced sound sources than sound pressure or sound intensity, especially...... extensively been used for many years to locate sound sources. However, it is not yet well defined when two sources should be regarded as resolved by means of direct sound mapping. This paper derives the limits of the direct representation of sound pressure, particle velocity and sound intensity by exploring......One of the main challenges arising from noise and vibration problems is how to identify the areas of a device, machine or structure that produce significant acoustic excitation, i.e. the localization of main noise sources. The direct visualization of sound, in particular sound intensity, has...

  11. DRIFT-FREE INDOOR NAVIGATION USING SIMULTANEOUS LOCALIZATION AND MAPPING OF THE AMBIENT HETEROGENEOUS MAGNETIC FIELD

    Directory of Open Access Journals (Sweden)

    J. C. K. Chow

    2017-09-01

    Full Text Available In the absence of external reference position information (e.g. surveyed targets or Global Navigation Satellite Systems Simultaneous Localization and Mapping (SLAM has proven to be an effective method for indoor navigation. The positioning drift can be reduced with regular loop-closures and global relaxation as the backend, thus achieving a good balance between exploration and exploitation. Although vision-based systems like laser scanners are typically deployed for SLAM, these sensors are heavy, energy inefficient, and expensive, making them unattractive for wearables or smartphone applications. However, the concept of SLAM can be extended to non-optical systems such as magnetometers. Instead of matching features such as walls and furniture using some variation of the Iterative Closest Point algorithm, the local magnetic field can be matched to provide loop-closure and global trajectory updates in a Gaussian Process (GP SLAM framework. With a MEMS-based inertial measurement unit providing a continuous trajectory, and the matching of locally distinct magnetic field maps, experimental results in this paper show that a drift-free navigation solution in an indoor environment with millimetre-level accuracy can be achieved. The GP-SLAM approach presented can be formulated as a maximum a posteriori estimation problem and it can naturally perform loop-detection, feature-to-feature distance minimization, global trajectory optimization, and magnetic field map estimation simultaneously. Spatially continuous features (i.e. smooth magnetic field signatures are used instead of discrete feature correspondences (e.g. point-to-point as in conventional vision-based SLAM. These position updates from the ambient magnetic field also provide enough information for calibrating the accelerometer bias and gyroscope bias in-use. The only restriction for this method is the need for magnetic disturbances (which is typically not an issue for indoor environments; however

  12. Drift-Free Indoor Navigation Using Simultaneous Localization and Mapping of the Ambient Heterogeneous Magnetic Field

    Science.gov (United States)

    Chow, J. C. K.

    2017-09-01

    In the absence of external reference position information (e.g. surveyed targets or Global Navigation Satellite Systems) Simultaneous Localization and Mapping (SLAM) has proven to be an effective method for indoor navigation. The positioning drift can be reduced with regular loop-closures and global relaxation as the backend, thus achieving a good balance between exploration and exploitation. Although vision-based systems like laser scanners are typically deployed for SLAM, these sensors are heavy, energy inefficient, and expensive, making them unattractive for wearables or smartphone applications. However, the concept of SLAM can be extended to non-optical systems such as magnetometers. Instead of matching features such as walls and furniture using some variation of the Iterative Closest Point algorithm, the local magnetic field can be matched to provide loop-closure and global trajectory updates in a Gaussian Process (GP) SLAM framework. With a MEMS-based inertial measurement unit providing a continuous trajectory, and the matching of locally distinct magnetic field maps, experimental results in this paper show that a drift-free navigation solution in an indoor environment with millimetre-level accuracy can be achieved. The GP-SLAM approach presented can be formulated as a maximum a posteriori estimation problem and it can naturally perform loop-detection, feature-to-feature distance minimization, global trajectory optimization, and magnetic field map estimation simultaneously. Spatially continuous features (i.e. smooth magnetic field signatures) are used instead of discrete feature correspondences (e.g. point-to-point) as in conventional vision-based SLAM. These position updates from the ambient magnetic field also provide enough information for calibrating the accelerometer bias and gyroscope bias in-use. The only restriction for this method is the need for magnetic disturbances (which is typically not an issue for indoor environments); however, no assumptions

  13. Bridging scale gaps between regional maps of forest aboveground biomass and field sampling plots using TanDEM-X data

    Science.gov (United States)

    Ni, W.; Zhang, Z.; Sun, G.

    2017-12-01

    Several large-scale maps of forest AGB have been released [1] [2] [3]. However, these existing global or regional datasets were only approximations based on combining land cover type and representative values instead of measurements of actual forest aboveground biomass or forest heights [4]. Rodríguez-Veiga et al[5] reported obvious discrepancies of existing forest biomass stock maps with in-situ observations in Mexico. One of the biggest challenges to the credibility of these maps comes from the scale gaps between the size of field sampling plots used to develop(or validate) estimation models and the pixel size of these maps and the availability of field sampling plots with sufficient size for the verification of these products [6]. It is time-consuming and labor-intensive to collect sufficient number of field sampling data over the plot size of the same as resolutions of regional maps. The smaller field sampling plots cannot fully represent the spatial heterogeneity of forest stands as shown in Figure 1. Forest AGB is directly determined by forest heights, diameter at breast height (DBH) of each tree, forest density and tree species. What measured in the field sampling are the geometrical characteristics of forest stands including the DBH, tree heights and forest densities. The LiDAR data is considered as the best dataset for the estimation of forest AGB. The main reason is that LiDAR can directly capture geometrical features of forest stands by its range detection capabilities.The remotely sensed dataset, which is capable of direct measurements of forest spatial structures, may serve as a ladder to bridge the scale gaps between the pixel size of regional maps of forest AGB and field sampling plots. Several researches report that TanDEM-X data can be used to characterize the forest spatial structures [7, 8]. In this study, the forest AGB map of northeast China were produced using ALOS/PALSAR data taking TanDEM-X data as a bridges. The TanDEM-X InSAR data used in

  14. Further results for crack-edge mappings by ray methods

    International Nuclear Information System (INIS)

    Norris, A.N.; Achenbach, J.D.; Ahlberg, L.; Tittman, B.R.

    1984-01-01

    This chapter discusses further extensions of the local edge mapping method to the pulse-echo case and to configurations of water-immersed specimens and transducers. Crack edges are mapped by the use of arrival times of edge-diffracted signals. Topics considered include local edge mapping in a homogeneous medium, local edge mapping algorithms, local edge mapping through an interface, and edge mapping through an interface using synthetic data. Local edge mapping is iterative, with two or three iterations required for convergence

  15. Smart watch RSSI localization and refinement for behavioral classification using laser-SLAM for mapping and fingerprinting.

    Science.gov (United States)

    Carlson, Jay D; Mittek, Mateusz; Parkison, Steven A; Sathler, Pedro; Bayne, David; Psota, Eric T; Perez, Lance C; Bonasera, Stephen J

    2014-01-01

    As a first step toward building a smart home behavioral monitoring system capable of classifying a wide variety of human behavior, a wireless sensor network (WSN) system is presented for RSSI localization. The low-cost, non-intrusive system uses a smart watch worn by the user to broadcast data to the WSN, where the strength of the radio signal is evaluated at each WSN node to localize the user. A method is presented that uses simultaneous localization and mapping (SLAM) for system calibration, providing automated fingerprinting associating the radio signal strength patterns to the user's location within the living space. To improve the accuracy of localization, a novel refinement technique is introduced that takes into account typical movement patterns of people within their homes. Experimental results demonstrate that the system is capable of providing accurate localization results in a typical living space.

  16. Magnetoresistance sensitivity mapping of the localized response of contiguous and lead-overlaid sensors

    International Nuclear Information System (INIS)

    Sankar, Sandra

    2003-01-01

    Magnetoresistance sensitivity mapping (MSM) was used to investigate the local response of magnetic recording sensors without convolution of the writer, magnetic media and data channel. From a 2D map of the local sensor response, the intrinsic pulse shape and magnetic track profile are readily obtained. Pulse-width is a concern for high data rate since if pulse-width is too broad, individual transitions become difficult to distinguish. Track profiles are important because due to the small difference between magnetic write-width and magnetic read-width, side reading will lead to an increase in noise. Three experiments are discussed: the dependence of the pulse-width (PW50) of the standard contiguous junction (CJ) design on shield-to-shield spacing; a comparison of the pulse shape of lead-overlaid (LOL) and CJ designs; and a comparison of the magnetic track profile (including track-width and skirt ratio) of LOL and CJ designs. The LOL design offers an increased sensitivity; however, as seen from MSM, the penalties are broadening of the track and pulse profiles. These are a direct result of the finite current in the lead overlay region and an increased shield-to-shield spacing in that region. The MSM image shows a curvature, which is associated with the topography of the top shield due to the lead overlay

  17. Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping.

    Science.gov (United States)

    Hamalainen, Sampsa; Geng, Xiaoyuan; He, Juanxia

    2017-04-01

    Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping. Sampsa Hamalainen, Xiaoyuan Geng, and Juanxia, He. AAFC - Agriculture and Agr-Food Canada, Ottawa, Canada. The Latin Hypercube Sampling (LHS) approach to assist with Digital Soil Mapping has been developed for some time now, however the purpose of this work was to complement LHS with use of multiple spatial resolutions of covariate datasets and variability in the range of sampling points produced. This allowed for specific sets of LHS points to be produced to fulfil the needs of various partners from multiple projects working in the Ontario and Prince Edward Island provinces of Canada. Secondary soil and environmental attributes are critical inputs that are required in the development of sampling points by LHS. These include a required Digital Elevation Model (DEM) and subsequent covariate datasets produced as a result of a Digital Terrain Analysis performed on the DEM. These additional covariates often include but are not limited to Topographic Wetness Index (TWI), Length-Slope (LS) Factor, and Slope which are continuous data. The range of specific points created in LHS included 50 - 200 depending on the size of the watershed and more importantly the number of soil types found within. The spatial resolution of covariates included within the work ranged from 5 - 30 m. The iterations within the LHS sampling were run at an optimal level so the LHS model provided a good spatial representation of the environmental attributes within the watershed. Also, additional covariates were included in the Latin Hypercube Sampling approach which is categorical in nature such as external Surficial Geology data. Some initial results of the work include using a 1000 iteration variable within the LHS model. 1000 iterations was consistently a reasonable value used to produce sampling points that provided a good spatial representation of the environmental

  18. Application of self-organising maps towards segmentation of soybean samples by determination of amino acids concentration.

    Science.gov (United States)

    Silva, Lívia Ramazzoti Chanan; Angilelli, Karina Gomes; Cremasco, Hágata; Romagnoli, Érica Signori; Galão, Olívio Fernandes; Borsato, Dionisio; Moraes, Larissa Alexandra Cardoso; Mandarino, José Marcos Gontijo

    2016-09-01

    Soybeans are widely used both for human nutrition and animal feed, since they are an important source of protein, and they also provide components such as phytosterols, isoflavones, and amino acids. In this study, were determined the concentrations of the amino acids lysine, histidine, arginine, asparagine, glutamic acid, glycine, alanine, valine, isoleucine, leucine, tyrosine, phenylalanine present in 14 samples of conventional soybeans and 6 transgenic, cultivated in two cities of the state of Paraná, Londrina and Ponta Grossa. The results were tabulated and presented to a self-organising map for segmentation according planting regions and conventional or transgenic varieties. A network with 7000 training epochs and a 10 × 10 topology was used, and it proved appropriate in the segmentation of the samples using the data analysed. The weight maps provided by the network, showed that all the amino acids were important in targeting the samples, especially isoleucine. Three clusters were formed, one with only Ponta Grossa samples (including transgenic (PGT) and common (PGC)), a second group with Londrina transgenic (LT) samples and the third with Londrina common (LC) samples. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  19. Indoor Localization Algorithms for an Ambulatory Human Operated 3D Mobile Mapping System

    Directory of Open Access Journals (Sweden)

    Nicholas Corso

    2013-12-01

    Full Text Available Indoor localization and mapping is an important problem with many applications such as emergency response, architectural modeling, and historical preservation. In this paper, we develop an automatic, off-line pipeline for metrically accurate, GPS-denied, indoor 3D mobile mapping using a human-mounted backpack system consisting of a variety of sensors. There are three novel contributions in our proposed mapping approach. First, we present an algorithm which automatically detects loop closure constraints from an occupancy grid map. In doing so, we ensure that constraints are detected only in locations that are well conditioned for scan matching. Secondly, we address the problem of scan matching with poor initial condition by presenting an outlier-resistant, genetic scan matching algorithm that accurately matches scans despite a poor initial condition. Third, we present two metrics based on the amount and complexity of overlapping geometry in order to vet the estimated loop closure constraints. By doing so, we automatically prevent erroneous loop closures from degrading the accuracy of the reconstructed trajectory. The proposed algorithms are experimentally verified using both controlled and real-world data. The end-to-end system performance is evaluated using 100 surveyed control points in an office environment and obtains a mean accuracy of 10 cm. Experimental results are also shown on three additional datasets from real world environments including a 1500 meter trajectory in a warehouse sized retail shopping center.

  20. Affine-Invariant Geometric Constraints-Based High Accuracy Simultaneous Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Gangchen Hua

    2017-01-01

    Full Text Available In this study we describe a new appearance-based loop-closure detection method for online incremental simultaneous localization and mapping (SLAM using affine-invariant-based geometric constraints. Unlike other pure bag-of-words-based approaches, our proposed method uses geometric constraints as a supplement to improve accuracy. By establishing an affine-invariant hypothesis, the proposed method excludes incorrect visual words and calculates the dispersion of correctly matched visual words to improve the accuracy of the likelihood calculation. In addition, camera’s intrinsic parameters and distortion coefficients are adequate for this method. 3D measuring is not necessary. We use the mechanism of Long-Term Memory and Working Memory (WM to manage the memory. Only a limited size of the WM is used for loop-closure detection; therefore the proposed method is suitable for large-scale real-time SLAM. We tested our method using the CityCenter and Lip6Indoor datasets. Our proposed method results can effectively correct the typical false-positive localization of previous methods, thus gaining better recall ratios and better precision.

  1. Accuracy assessment of planimetric large-scale map data for decision-making

    Directory of Open Access Journals (Sweden)

    Doskocz Adam

    2016-06-01

    Full Text Available This paper presents decision-making risk estimation based on planimetric large-scale map data, which are data sets or databases which are useful for creating planimetric maps on scales of 1:5,000 or larger. The studies were conducted on four data sets of large-scale map data. Errors of map data were used for a risk assessment of decision-making about the localization of objects, e.g. for land-use planning in realization of investments. An analysis was performed for a large statistical sample set of shift vectors of control points, which were identified with the position errors of these points (errors of map data.

  2. Mapping social-ecological vulnerability to inform local decision making.

    Science.gov (United States)

    Thiault, Lauric; Marshall, Paul; Gelcich, Stefan; Collin, Antoine; Chlous, Frédérique; Claudet, Joachim

    2018-04-01

    An overarching challenge of natural resource management and biodiversity conservation is that relationships between people and nature are difficult to integrate into tools that can effectively guide decision making. Social-ecological vulnerability offers a valuable framework for identifying and understanding important social-ecological linkages, and the implications of dependencies and other feedback loops in the system. Unfortunately, its implementation at local scales has hitherto been limited due at least in part to the lack of operational tools for spatial representation of social-ecological vulnerability. We developed a method to map social-ecological vulnerability based on information on human-nature dependencies and ecosystem services at local scales. We applied our method to the small-scale fishery of Moorea, French Polynesia, by combining spatially explicit indicators of exposure, sensitivity, and adaptive capacity of both the resource (i.e., vulnerability of reef fish assemblages to fishing) and resource users (i.e., vulnerability of fishing households to the loss of fishing opportunity). Our results revealed that both social and ecological vulnerabilities varied considerably through space and highlighted areas where sources of vulnerability were high for both social and ecological subsystems (i.e., social-ecological vulnerability hotspots) and thus of high priority for management intervention. Our approach can be used to inform decisions about where biodiversity conservation strategies are likely to be more effective and how social impacts from policy decisions can be minimized. It provides a new perspective on human-nature linkages that can help guide sustainability management at local scales; delivers insights distinct from those provided by emphasis on a single vulnerability component (e.g., exposure); and demonstrates the feasibility and value of operationalizing the social-ecological vulnerability framework for policy, planning, and participatory

  3. Mapping cell populations in flow cytometry data for cross-sample comparison using the Friedman-Rafsky test statistic as a distance measure.

    Science.gov (United States)

    Hsiao, Chiaowen; Liu, Mengya; Stanton, Rick; McGee, Monnie; Qian, Yu; Scheuermann, Richard H

    2016-01-01

    Flow cytometry (FCM) is a fluorescence-based single-cell experimental technology that is routinely applied in biomedical research for identifying cellular biomarkers of normal physiological responses and abnormal disease states. While many computational methods have been developed that focus on identifying cell populations in individual FCM samples, very few have addressed how the identified cell populations can be matched across samples for comparative analysis. This article presents FlowMap-FR, a novel method for cell population mapping across FCM samples. FlowMap-FR is based on the Friedman-Rafsky nonparametric test statistic (FR statistic), which quantifies the equivalence of multivariate distributions. As applied to FCM data by FlowMap-FR, the FR statistic objectively quantifies the similarity between cell populations based on the shapes, sizes, and positions of fluorescence data distributions in the multidimensional feature space. To test and evaluate the performance of FlowMap-FR, we simulated the kinds of biological and technical sample variations that are commonly observed in FCM data. The results show that FlowMap-FR is able to effectively identify equivalent cell populations between samples under scenarios of proportion differences and modest position shifts. As a statistical test, FlowMap-FR can be used to determine whether the expression of a cellular marker is statistically different between two cell populations, suggesting candidates for new cellular phenotypes by providing an objective statistical measure. In addition, FlowMap-FR can indicate situations in which inappropriate splitting or merging of cell populations has occurred during gating procedures. We compared the FR statistic with the symmetric version of Kullback-Leibler divergence measure used in a previous population matching method with both simulated and real data. The FR statistic outperforms the symmetric version of KL-distance in distinguishing equivalent from nonequivalent cell

  4. The impact of sample size on the reproducibility of voxel-based lesion-deficit mappings.

    Science.gov (United States)

    Lorca-Puls, Diego L; Gajardo-Vidal, Andrea; White, Jitrachote; Seghier, Mohamed L; Leff, Alexander P; Green, David W; Crinion, Jenny T; Ludersdorfer, Philipp; Hope, Thomas M H; Bowman, Howard; Price, Cathy J

    2018-07-01

    This study investigated how sample size affects the reproducibility of findings from univariate voxel-based lesion-deficit analyses (e.g., voxel-based lesion-symptom mapping and voxel-based morphometry). Our effect of interest was the strength of the mapping between brain damage and speech articulation difficulties, as measured in terms of the proportion of variance explained. First, we identified a region of interest by searching on a voxel-by-voxel basis for brain areas where greater lesion load was associated with poorer speech articulation using a large sample of 360 right-handed English-speaking stroke survivors. We then randomly drew thousands of bootstrap samples from this data set that included either 30, 60, 90, 120, 180, or 360 patients. For each resample, we recorded effect size estimates and p values after conducting exactly the same lesion-deficit analysis within the previously identified region of interest and holding all procedures constant. The results show (1) how often small effect sizes in a heterogeneous population fail to be detected; (2) how effect size and its statistical significance varies with sample size; (3) how low-powered studies (due to small sample sizes) can greatly over-estimate as well as under-estimate effect sizes; and (4) how large sample sizes (N ≥ 90) can yield highly significant p values even when effect sizes are so small that they become trivial in practical terms. The implications of these findings for interpreting the results from univariate voxel-based lesion-deficit analyses are discussed. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  5. Soil map disaggregation improved by soil-landscape relationships, area-proportional sampling and random forest implementation

    DEFF Research Database (Denmark)

    Møller, Anders Bjørn; Malone, Brendan P.; Odgers, Nathan

    implementation generally improved the algorithm’s ability to predict the correct soil class. The implementation of soil-landscape relationships and area-proportional sampling generally increased the calculation time, while the random forest implementation reduced the calculation time. In the most successful......Detailed soil information is often needed to support agricultural practices, environmental protection and policy decisions. Several digital approaches can be used to map soil properties based on field observations. When soil observations are sparse or missing, an alternative approach...... is to disaggregate existing conventional soil maps. At present, the DSMART algorithm represents the most sophisticated approach for disaggregating conventional soil maps (Odgers et al., 2014). The algorithm relies on classification trees trained from resampled points, which are assigned classes according...

  6. Concurrent Cognitive Mapping and Localization Using Expectation Maximization

    National Research Council Canada - National Science Library

    Laviers, Kennard

    2004-01-01

    ...) views the world as a series of connected spaces. These spaces are initially mapped as an occupancy grid in a room-by-room fashion using a modified version of the Histogram In Motion Mapping (HIMM...

  7. Bedrock Geologic Map of Vermont - Geochronology Sample Locations

    Data.gov (United States)

    Vermont Center for Geographic Information — The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale...

  8. Mapping Vineyard Leaf Area Using Mobile Terrestrial Laser Scanners: Should Rows be Scanned On-the-Go or Discontinuously Sampled?

    Directory of Open Access Journals (Sweden)

    Ignacio del-Moral-Martínez

    2016-01-01

    Full Text Available The leaf area index (LAI is defined as the one-side leaf area per unit ground area, and is probably the most widely used index to characterize grapevine vigor. However, LAI varies spatially within vineyard plots. Mapping and quantifying this variability is very important for improving management decisions and agricultural practices. In this study, a mobile terrestrial laser scanner (MTLS was used to map the LAI of a vineyard, and then to examine how different scanning methods (on-the-go or discontinuous systematic sampling may affect the reliability of the resulting raster maps. The use of the MTLS allows calculating the enveloping vegetative area of the canopy, which is the sum of the leaf wall areas for both sides of the row (excluding gaps and the projected upper area. Obtaining the enveloping areas requires scanning from both sides one meter length section along the row at each systematic sampling point. By converting the enveloping areas into LAI values, a raster map of the latter can be obtained by spatial interpolation (kriging. However, the user can opt for scanning on-the-go in a continuous way and compute 1-m LAI values along the rows, or instead, perform the scanning at discontinuous systematic sampling within the plot. An analysis of correlation between maps indicated that MTLS can be used discontinuously in specific sampling sections separated by up to 15 m along the rows. This capability significantly reduces the amount of data to be acquired at field level, the data storage capacity and the processing power of computers.

  9. Wind class sampling of satellite SAR imagery for offshore wind resource mapping

    DEFF Research Database (Denmark)

    Badger, Merete; Badger, Jake; Nielsen, Morten

    2010-01-01

    developed for mesoscale modeling of wind resources. Its performance in connection with sampling of SAR scenes is tested against two sets of random SAR samples and meteorological observations at three sites in the North Sea during 2005–08. Predictions of the mean wind speed and the Weibull scale parameter......High-resolution wind fields retrieved from satellite synthetic aperture radar (SAR) imagery are combined for mapping of wind resources offshore where site measurements are costly and sparse. A new sampling strategy for the SAR scenes is introduced, based on a method for statistical......-dynamical downscaling of large-scale wind conditions using a set of wind classes that describe representative wind situations. One or more SAR scenes are then selected to represent each wind class and the classes are weighted according to their frequency of occurrence. The wind class methodology was originally...

  10. Understanding and mapping local conflicts related to protected areas in small islands: a case study of the Azores archipelago

    Directory of Open Access Journals (Sweden)

    Chiara Bragagnolo

    2016-05-01

    Full Text Available Establishing Protected Areas (PAs is considered one of the most appropriate ways to conserve nature and cultural landscapes. However, conservation constraints can generate social conflicts, especially at a local level. In small islands (SIs, local conflicts may escalate due to an increase in competition for limited space and resources. Pico island in the Azores Archipelago (Portugal, part of the Outermost European region, was considered a good case to study conservation-development conflicts due to the amount of designated protected land (> 35% of its surface and the approval of a new Azorean PA network in 2007. This paper presents a new approach to understanding and mapping local conflicts within PAs in SIs by integrating qualitative data and spatially explicit information. This research takes stock of the benefits, needs and constraints related to Pico Natural Park as perceived by local stakeholders through face-to-face semi-structured interviews; it subsequently identifies and transposes the conflicts distilled from stakeholder discourse into spatially representative visual maps via GIS. Research outcomes show that PAs are perceived mainly as constraints to local development, showing inconsistency between local expectations and regional conservation policy. This highlights the importance of including public participation processes prior to any implementation of conservation strategies. The proposed method provides a springboard towards effective conflict management for PAs on Pico island, showing a relatively low-cost and straightforward approach to minimising future local conflicts which could be adapted to other similar Outermost European regions and SIs.

  11. Performance of local information-based link prediction: a sampling perspective

    Science.gov (United States)

    Zhao, Jichang; Feng, Xu; Dong, Li; Liang, Xiao; Xu, Ke

    2012-08-01

    Link prediction is pervasively employed to uncover the missing links in the snapshots of real-world networks, which are usually obtained through different kinds of sampling methods. In the previous literature, in order to evaluate the performance of the prediction, known edges in the sampled snapshot are divided into the training set and the probe set randomly, without considering the underlying sampling approaches. However, different sampling methods might lead to different missing links, especially for the biased ways. For this reason, random partition-based evaluation of performance is no longer convincing if we take the sampling method into account. In this paper, we try to re-evaluate the performance of local information-based link predictions through sampling method governed division of the training set and the probe set. It is interesting that we find that for different sampling methods, each prediction approach performs unevenly. Moreover, most of these predictions perform weakly when the sampling method is biased, which indicates that the performance of these methods might have been overestimated in the prior works.

  12. Practical indoor mobile robot navigation using hybrid maps

    DEFF Research Database (Denmark)

    Özkil, Ali Gürcan; Fan, Zhun; Xiao, Jizhong

    2011-01-01

    This paper presents a practical navigation scheme for indoor mobile robots using hybrid maps. The method makes use of metric maps for local navigation and a topological map for global path planning. Metric maps are generated as 2D occupancy grids by a range sensor to represent local information...... about partial areas. The global topological map is used to indicate the connectivity of the 'places-of-interests' in the environment and the interconnectivity of the local maps. Visual tags on the ceiling to be detected by the robot provide valuable information and contribute to reliable localization...... robot and evaluated in a hospital environment....

  13. Synchronizing spatiotemporal chaos by introducing a finite flat region in the local map

    Directory of Open Access Journals (Sweden)

    J. Y. Chen

    2001-01-01

    Full Text Available An approach to synchronize spatiotemporal chaos is proposed. It is achieved by introducing a finite flat region in the local map. By using this scheme, a number of orbits in both the drive and the response subsystems are forced to pass through a fixed point in every dimension. With only an arbitrary phase space variable as drive signal, synchronization of spatiotemporal chaos can be achieved rapidly in the response subsystem. This is an advantage when compared with other synchronization methods that require a linear combination of the original phase space variables.

  14. Locally Linear Embedding of Local Orthogonal Least Squares Images for Face Recognition

    Science.gov (United States)

    Hafizhelmi Kamaru Zaman, Fadhlan

    2018-03-01

    Dimensionality reduction is very important in face recognition since it ensures that high-dimensionality data can be mapped to lower dimensional space without losing salient and integral facial information. Locally Linear Embedding (LLE) has been previously used to serve this purpose, however, the process of acquiring LLE features requires high computation and resources. To overcome this limitation, we propose a locally-applied Local Orthogonal Least Squares (LOLS) model can be used as initial feature extraction before the application of LLE. By construction of least squares regression under orthogonal constraints we can preserve more discriminant information in the local subspace of facial features while reducing the overall features into a more compact form that we called LOLS images. LLE can then be applied on the LOLS images to maps its representation into a global coordinate system of much lower dimensionality. Several experiments carried out using publicly available face datasets such as AR, ORL, YaleB, and FERET under Single Sample Per Person (SSPP) constraint demonstrates that our proposed method can reduce the time required to compute LLE features while delivering better accuracy when compared to when either LLE or OLS alone is used. Comparison against several other feature extraction methods and more recent feature-learning method such as state-of-the-art Convolutional Neural Networks (CNN) also reveal the superiority of the proposed method under SSPP constraint.

  15. Enhancement of bone shadow region using local phase-based ultrasound transmission maps.

    Science.gov (United States)

    Hacihaliloglu, Ilker

    2017-06-01

    Ultrasound is increasingly being employed in different orthopedic procedures as an imaging modality for real-time guidance. Nevertheless, low signal-to-noise-ratio and different imaging artifacts continue to hamper the success of ultrasound-based procedures. Bone shadow region is an important feature indicating the presence of bone/tissue interface in the acquired ultrasound data. Enhancement and automatic detection of this region could improve the sensitivity of ultrasound for imaging bone and result in improved guidance for various orthopedic procedures. In this work, a method is introduced for the enhancement of bone shadow regions from B-mode ultrasound data. The method is based on the combination of three different image phase features: local phase tensor, local weighted mean phase angle, and local phase energy. The combined local phase image features are used as an input to an [Formula: see text] norm-based contextual regularization method which emphasizes uncertainty in the shadow regions. The enhanced bone shadow images are automatically segmented and compared against expert segmentation. Qualitative and quantitative validation was performed on 100 in vivo US scans obtained from five subjects by scanning femur and vertebrae bones. Validation against expert segmentation achieved a mean dice similarity coefficient of 0.88. The encouraging results obtained in this initial study suggest that the proposed method is promising enough for further evaluation. The calculated bone shadow maps could be incorporated into different ultrasound bone segmentation and registration approaches as an additional feature.

  16. Two-dimensional T2 distribution mapping in rock core plugs with optimal k-space sampling.

    Science.gov (United States)

    Xiao, Dan; Balcom, Bruce J

    2012-07-01

    Spin-echo single point imaging has been employed for 1D T(2) distribution mapping, but a simple extension to 2D is challenging since the time increase is n fold, where n is the number of pixels in the second dimension. Nevertheless 2D T(2) mapping in fluid saturated rock core plugs is highly desirable because the bedding plane structure in rocks often results in different pore properties within the sample. The acquisition time can be improved by undersampling k-space. The cylindrical shape of rock core plugs yields well defined intensity distributions in k-space that may be efficiently determined by new k-space sampling patterns that are developed in this work. These patterns acquire 22.2% and 11.7% of the k-space data points. Companion density images may be employed, in a keyhole imaging sense, to improve image quality. T(2) weighted images are fit to extract T(2) distributions, pixel by pixel, employing an inverse Laplace transform. Images reconstructed with compressed sensing, with similar acceleration factors, are also presented. The results show that restricted k-space sampling, in this application, provides high quality results. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Reproducibility of somatosensory spatial perceptual maps.

    Science.gov (United States)

    Steenbergen, Peter; Buitenweg, Jan R; Trojan, Jörg; Veltink, Peter H

    2013-02-01

    Various studies have shown subjects to mislocalize cutaneous stimuli in an idiosyncratic manner. Spatial properties of individual localization behavior can be represented in the form of perceptual maps. Individual differences in these maps may reflect properties of internal body representations, and perceptual maps may therefore be a useful method for studying these representations. For this to be the case, individual perceptual maps need to be reproducible, which has not yet been demonstrated. We assessed the reproducibility of localizations measured twice on subsequent days. Ten subjects participated in the experiments. Non-painful electrocutaneous stimuli were applied at seven sites on the lower arm. Subjects localized the stimuli on a photograph of their own arm, which was presented on a tablet screen overlaying the real arm. Reproducibility was assessed by calculating intraclass correlation coefficients (ICC) for the mean localizations of each electrode site and the slope and offset of regression models of the localizations, which represent scaling and displacement of perceptual maps relative to the stimulated sites. The ICCs of the mean localizations ranged from 0.68 to 0.93; the ICCs of the regression parameters were 0.88 for the intercept and 0.92 for the slope. These results indicate a high degree of reproducibility. We conclude that localization patterns of non-painful electrocutaneous stimuli on the arm are reproducible on subsequent days. Reproducibility is a necessary property of perceptual maps for these to reflect properties of a subject's internal body representations. Perceptual maps are therefore a promising method for studying body representations.

  18. Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

    Science.gov (United States)

    Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

    2013-06-01

    As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

  19. Subspace preservation, subspace locality, and gluing of completely positive maps

    International Nuclear Information System (INIS)

    Aaberg, Johan

    2004-01-01

    Three concepts concerning completely positive maps (CPMs) and trace preserving CPMs (channels) are introduced and investigated. These are named subspace preserving (SP) CPMs, subspace local (SL) channels, and gluing of CPMs. SP CPMs has, in the case of trace preserving CPMs, a simple interpretation as those which preserve probability weights on a given orthogonal sum decomposition of the Hilbert space of a quantum system. The proposed definition of subspace locality of quantum channels is an attempt to answer the question of what kind of restriction should be put on a channel, if it is to act 'locally' with respect to two 'locations', when these naturally correspond to a separation of the total Hilbert space in an orthogonal sum of subspaces, rather than a tensor product decomposition. As a description of the concept of gluings of quantum channels, consider a pair of 'evolution machines', each with the ability to evolve the internal state of a 'particle' inserted into its input. Each of these machines is characterized by a channel describing the operation the internal state has experienced when the particle is returned at the output. Suppose a particle is put in a superposition between the input of the first and the second machine. Here it is shown that the total evolution caused by a pair of such devices is not uniquely determined by the channels of the two machines. Such 'global' channels describing the machine pair are examples of gluings of the two single machine channels. Various expressions to generate the set of SP and SL channels, as well as expressions to generate the set of gluings of given channels, are deduced. We discuss conceptual aspects of the nature of these channels and the nature of the non-uniqueness of gluings

  20. Range-efficient consistent sampling and locality-sensitive hashing for polygons

    DEFF Research Database (Denmark)

    Gudmundsson, Joachim; Pagh, Rasmus

    2017-01-01

    Locality-sensitive hashing (LSH) is a fundamental technique for similarity search and similarity estimation in high-dimensional spaces. The basic idea is that similar objects should produce hash collisions with probability significantly larger than objects with low similarity. We consider LSH for...... or union of a set of preprocessed polygons. Curiously, our consistent sampling method uses transformation to a geometric problem....

  1. Estimating cross-validatory predictive p-values with integrated importance sampling for disease mapping models.

    Science.gov (United States)

    Li, Longhai; Feng, Cindy X; Qiu, Shi

    2017-06-30

    An important statistical task in disease mapping problems is to identify divergent regions with unusually high or low risk of disease. Leave-one-out cross-validatory (LOOCV) model assessment is the gold standard for estimating predictive p-values that can flag such divergent regions. However, actual LOOCV is time-consuming because one needs to rerun a Markov chain Monte Carlo analysis for each posterior distribution in which an observation is held out as a test case. This paper introduces a new method, called integrated importance sampling (iIS), for estimating LOOCV predictive p-values with only Markov chain samples drawn from the posterior based on a full data set. The key step in iIS is that we integrate away the latent variables associated the test observation with respect to their conditional distribution without reference to the actual observation. By following the general theory for importance sampling, the formula used by iIS can be proved to be equivalent to the LOOCV predictive p-value. We compare iIS and other three existing methods in the literature with two disease mapping datasets. Our empirical results show that the predictive p-values estimated with iIS are almost identical to the predictive p-values estimated with actual LOOCV and outperform those given by the existing three methods, namely, the posterior predictive checking, the ordinary importance sampling, and the ghosting method by Marshall and Spiegelhalter (2003). Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  2. MAPPING LOCAL CLIMATE ZONES WITH A VECTOR-BASED GIS METHOD

    Directory of Open Access Journals (Sweden)

    E. Lelovics

    2013-03-01

    Full Text Available In this study we determined Local Climate Zones in a South-Hungarian city, using vector-based and raster-based databases. We calculated seven of the originally proposed ten physical (geometric, surface cover and radiative properties for areas which are based on the mobile temperature measurement campaigns earlier carried out in this city.As input data we applied 3D building database (earlier created with photogrammetric methods, 2D road database, topographic map, aerial photographs, remotely sensed reflectance information from RapidEye satellite image and our local knowledge about the area. The values of the properties were calculated by GIS methods developed for this purpose.We derived for the examined areas and applied for classification sky view factor, mean building height, terrain roughness class, building surface fraction, pervious surface fraction, impervious surface fraction and albedo.Six built and one land cover LCZ classes could be detected with this method on our study area. From each class one circle area was selected, which is representative for that class. Their thermal reactions were examined with the application of mobile temperature measurement dataset. The comparison was made in cases, when the weather was clear and calm and the surface was dry. We found that compact built-in types have more temperature surplus than open ones, and midrise types also have more than lowrise ones. According to our primary results, these categories provide a useful opportunity for intra- and inter-urban comparisons.

  3. Advancing the quantification of humid tropical forest cover loss with multi-resolution optical remote sensing data: Sampling & wall-to-wall mapping

    Science.gov (United States)

    Broich, Mark

    Humid tropical forest cover loss is threatening the sustainability of ecosystem goods and services as vast forest areas are rapidly cleared for industrial scale agriculture and tree plantations. Despite the importance of humid tropical forest in the provision of ecosystem services and economic development opportunities, the spatial and temporal distribution of forest cover loss across large areas is not well quantified. Here I improve the quantification of humid tropical forest cover loss using two remote sensing-based methods: sampling and wall-to-wall mapping. In all of the presented studies, the integration of coarse spatial, high temporal resolution data with moderate spatial, low temporal resolution data enable advances in quantifying forest cover loss in the humid tropics. Imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) are used as the source of coarse spatial resolution, high temporal resolution data and imagery from the Landsat Enhanced Thematic Mapper Plus (ETM+) sensor are used as the source of moderate spatial, low temporal resolution data. In a first study, I compare the precision of different sampling designs for the Brazilian Amazon using the annual deforestation maps derived by the Brazilian Space Agency for reference. I show that sampling designs can provide reliable deforestation estimates; furthermore, sampling designs guided by MODIS data can provide more efficient estimates than the systematic design used for the United Nations Food and Agricultural Organization Forest Resource Assessment 2010. Sampling approaches, such as the one demonstrated, are viable in regions where data limitations, such as cloud contamination, limit exhaustive mapping methods. Cloud-contaminated regions experiencing high rates of change include Insular Southeast Asia, specifically Indonesia and Malaysia. Due to persistent cloud cover, forest cover loss in Indonesia has only been mapped at a 5-10 year interval using photo interpretation of single

  4. Multidrug resistance among new tuberculosis cases: detecting local variation through lot quality-assurance sampling.

    Science.gov (United States)

    Hedt, Bethany Lynn; van Leth, Frank; Zignol, Matteo; Cobelens, Frank; van Gemert, Wayne; Nhung, Nguyen Viet; Lyepshina, Svitlana; Egwaga, Saidi; Cohen, Ted

    2012-03-01

    Current methodology for multidrug-resistant tuberculosis (MDR TB) surveys endorsed by the World Health Organization provides estimates of MDR TB prevalence among new cases at the national level. On the aggregate, local variation in the burden of MDR TB may be masked. This paper investigates the utility of applying lot quality-assurance sampling to identify geographic heterogeneity in the proportion of new cases with multidrug resistance. We simulated the performance of lot quality-assurance sampling by applying these classification-based approaches to data collected in the most recent TB drug-resistance surveys in Ukraine, Vietnam, and Tanzania. We explored 3 classification systems- two-way static, three-way static, and three-way truncated sequential sampling-at 2 sets of thresholds: low MDR TB = 2%, high MDR TB = 10%, and low MDR TB = 5%, high MDR TB = 20%. The lot quality-assurance sampling systems identified local variability in the prevalence of multidrug resistance in both high-resistance (Ukraine) and low-resistance settings (Vietnam). In Tanzania, prevalence was uniformly low, and the lot quality-assurance sampling approach did not reveal variability. The three-way classification systems provide additional information, but sample sizes may not be obtainable in some settings. New rapid drug-sensitivity testing methods may allow truncated sequential sampling designs and early stopping within static designs, producing even greater efficiency gains. Lot quality-assurance sampling study designs may offer an efficient approach for collecting critical information on local variability in the burden of multidrug-resistant TB. Before this methodology is adopted, programs must determine appropriate classification thresholds, the most useful classification system, and appropriate weighting if unbiased national estimates are also desired.

  5. Dense 3D Map Construction for Indoor Search and Rescue

    DEFF Research Database (Denmark)

    Ellekilde, Lars-Peter; Huang, Shoudong; Miró, Jaime Valls

    2007-01-01

    The main contribution of this paper is a new simultaneous localization and mapping  SLAM algorithm for building dense three-dimensional maps using information ac- quired from a range imager and a conventional camera, for robotic search and rescue in unstructured indoor environments. A key challen...... invariant feature transformation SIFT feature detection and matching, random sampling consensus RANSAC , and least square 3D point sets ?tting. Experimental results are provided to demonstrate the effectiveness of the techniques developed....

  6. Impact of population structure, effective bottleneck time, and allele frequency on linkage disequilibrium maps.

    Science.gov (United States)

    Zhang, Weihua; Collins, Andrew; Gibson, Jane; Tapper, William J; Hunt, Sarah; Deloukas, Panos; Bentley, David R; Morton, Newton E

    2004-12-28

    Genetic maps in linkage disequilibrium (LD) units play the same role for association mapping as maps in centimorgans provide at much lower resolution for linkage mapping. Association mapping of genes determining disease susceptibility and other phenotypes is based on the theory of LD, here applied to relations with three phenomena. To test the theory, markers at high density along a 10-Mb continuous segment of chromosome 20q were studied in African-American, Asian, and Caucasian samples. Population structure, whether created by pooling samples from divergent populations or by the mating pattern in a mixed population, is accurately bioassayed from genotype frequencies. The effective bottleneck time for Eurasians is substantially less than for migration out of Africa, reflecting later bottlenecks. The classical dependence of allele frequency on mutation age does not hold for the generally shorter time span of inbreeding and LD. Limitation of the classical theory to mutation age justifies the assumption of constant time in a LD map, except for alleles that were rare at the effective bottleneck time or have arisen since. This assumption is derived from the Malecot model and verified in all samples. Tested measures of relative efficiency, support intervals, and localization error determine the operating characteristics of LD maps that are applicable to every sexually reproducing species, with implications for association mapping, high-resolution linkage maps, evolutionary inference, and identification of recombinogenic sequences.

  7. Flux mapping at 77 K and local measurement at lower temperature of thin-wall YBaCuO single-domain samples oxygenated under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Chaud, X., E-mail: Xavier.chaud@grenoble.cnrs.f [CRETA, CNRS, 25, Avenue des Martyrs, 38042 Grenoble Cedex 9 (France); Noudem, J. [CRISMAT/ENSICAEN, CNRS, 6 bd Marechal Juin, 14050 Caen (France); Prikhna, T.; Savchuk, Y. [ISM, National Acad. of Sciences of Ukraine, 2 Avtozavodskaya Street, Kiev, 04074 (Ukraine); Haanappel, E. [LNCMP, UMR 5147, 143 avenue de Rangueil, 31400 Toulouse (France); Diko, P. [IEP, Slovak Acad. of Sciences, Watsonova 47, 043 53, Kosice (Slovakia); Zhang, C.P. [SMRC, NIN, 96 Weiyang Road, Xi' an 710016 (China)

    2009-10-15

    YBCO single-domain samples are suitable for the production of high trapped fields in the range 20-77 K using a cryocooler or liquid nitrogen. But the oxygenation process required to actually transform the single domains into superconductors induces an extensive crack network that is limiting the material performances. Thin-wall geometry has been introduced to reduce the diffusion paths and to enable a progressive oxygenation strategy. As a consequence cracks are drastically reduced. In addition the use of a high oxygen pressure (16 MPa) speeds up further the process by displacing the oxygen-temperature equilibrium towards the higher temperature of the phase diagram. The advantage of thin-wall geometry is that such an annealing can be applied directly to a much larger sample. Remarkable results are obtained without any doping by the combination of thin walls and oxygen high pressure. While classical plain samples yield 300-400 mT, a trapped field of 840 mT has been measured at 77 K on a 16 mm diameter Y123 thin-wall single-domain sample with an annealing time as short as 3 days. Local measurements with a fixed Hall probe on top of the sample were performed at lower temperature after magnetization either in a static field or in a pulse field. The trapped field is significantly higher at lower temperature. Cryocoolers become the key to compromise between performances and cryogenic cost around 40 K.

  8. Mapping corrections for radon indoor data suggested by simulated data distributions

    International Nuclear Information System (INIS)

    Majerus, J.; Kies, A.; Tondeur, F.

    2004-01-01

    Indoor radon measurements may be considered as a stochastic function of spatial or spatio-temporal coordinates. This is characterized by a combination of deterministic and stochastic factors, including an important local 'noise' due to special indoor conditions. Radon mapping always consists in trying to smooth out the noise and possible outliers, to identify risk zones of high radon concentrations. To explore the spatial variation of radon we used indoor concentration data, obtained in Luxembourg and Belgium. These indoor radon databases have medium sampling density of 1 to 2 data per km 2 , respectively 0,3 data per km 2 . Furthermore we tried to investigate the relationship between geologic conditions and indoor radon concentrations. For indoor radon data, the best data sampling is restricted to all given house locations, thus we first investigated the ability to recover geological information with respect to the restricted indoor sampling distribution. To do so, we used simulated radon data with different sampling density and local clustering, generated by assuming specified average values depending on the coordinates, broadened by a typical log-normal noise and outliers of varying magnitude. Data clustering inside of villages and under-representation of the far field data locations leads to the well-known bull-eyes effects in mapping. Because the underlying deterministic structure of the simulated data is known, these data can be used to test different pre-treatments to apply before running a given gridding method. Adequate corrections for the non-uniform sampling distribution of radon indoor data can thus be explored. Furthermore, it is shown how simulated data can help to find good smoothing criteria. With smoothing needed, it may be difficult to find a good compromise between showing only significant features and showing more details at the risk of pointing out irrelevant details or even artifacts. Simulated data proved to be very useful in this context. In

  9. A Multi-Sensorial Simultaneous Localization and Mapping (SLAM) System for Low-Cost Micro Aerial Vehicles in GPS-Denied Environments.

    Science.gov (United States)

    López, Elena; García, Sergio; Barea, Rafael; Bergasa, Luis M; Molinos, Eduardo J; Arroyo, Roberto; Romera, Eduardo; Pardo, Samuel

    2017-04-08

    One of the main challenges of aerial robots navigation in indoor or GPS-denied environments is position estimation using only the available onboard sensors. This paper presents a Simultaneous Localization and Mapping (SLAM) system that remotely calculates the pose and environment map of different low-cost commercial aerial platforms, whose onboard computing capacity is usually limited. The proposed system adapts to the sensory configuration of the aerial robot, by integrating different state-of-the art SLAM methods based on vision, laser and/or inertial measurements using an Extended Kalman Filter (EKF). To do this, a minimum onboard sensory configuration is supposed, consisting of a monocular camera, an Inertial Measurement Unit (IMU) and an altimeter. It allows to improve the results of well-known monocular visual SLAM methods (LSD-SLAM and ORB-SLAM are tested and compared in this work) by solving scale ambiguity and providing additional information to the EKF. When payload and computational capabilities permit, a 2D laser sensor can be easily incorporated to the SLAM system, obtaining a local 2.5D map and a footprint estimation of the robot position that improves the 6D pose estimation through the EKF. We present some experimental results with two different commercial platforms, and validate the system by applying it to their position control.

  10. Digital technical map of Košice city

    Directory of Open Access Journals (Sweden)

    Štefan Kuzevič

    2007-06-01

    Full Text Available The digital map of a city is comprised complex of the map. Process of creation of the digital map of a city is time consuming and financially demanding. The digital map is created as co-operation of the local authority, technology network administrator, companies, and local government. The exact and current digital map of the city utilizable for multilateral applications is the result of this co-operation. The digital map of city catch all important phenomenon and objects which are needed for making decisions and planning to all grades controlling the local authority. The Geographic information systems tools make possible updating digital map, analyses and syntheses spatial phenomena and theirs relationships. The digital map of city is created step by step. The digital technical map of city is one of very important part of the digital map. Illustration of the part digital technical map of Košice is showed in the Fig. 1.

  11. Synchrotron-based FTIR microspectroscopy for the mapping of photo-oxidation and additives in acrylonitrile-butadiene-styrene model samples and historical objects.

    Science.gov (United States)

    Saviello, Daniela; Pouyet, Emeline; Toniolo, Lucia; Cotte, Marine; Nevin, Austin

    2014-09-16

    Synchrotron-based Fourier transform infrared micro-spectroscopy (SR-μFTIR) was used to map photo-oxidative degradation of acrylonitrile-butadiene-styrene (ABS) and to investigate the presence and the migration of additives in historical samples from important Italian design objects. High resolution (3×3 μm(2)) molecular maps were obtained by FTIR microspectroscopy in transmission mode, using a new method for the preparation of polymer thin sections. The depth of photo-oxidation in samples was evaluated and accompanied by the formation of ketones, aldehydes, esters, and unsaturated carbonyl compounds. This study demonstrates selective surface oxidation and a probable passivation of material against further degradation. In polymer fragments from design objects made of ABS from the 1960s, UV-stabilizers were detected and mapped, and microscopic inclusions of proteinaceous material were identified and mapped for the first time. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Mapping with Drupal

    CERN Document Server

    Palazzolo, Alan

    2011-01-01

    Build beautiful interactive maps on your Drupal website, and tell engaging visual stories with your data. This concise guide shows you how to create custom geographical maps from top to bottom, using Drupal 7 tools and out-of-the-box modules. You'll learn how mapping works in Drupal, with examples on how to use intuitive interfaces to map local events, businesses, groups, and other custom data. Although building maps with Drupal can be tricky, this book helps you navigate the system's complexities for creating sophisticated maps that match your site design. Get the knowledge and tools you ne

  13. Passive acoustic mapping of magnetic microbubbles for cavitation enhancement and localization

    International Nuclear Information System (INIS)

    Crake, Calum; Victor, Marie de Saint; Owen, Joshua; Coviello, Christian; Collin, Jamie; Coussios, Constantin-C; Stride, Eleanor

    2015-01-01

    Magnetic targeting of microbubbles functionalized with superparamagnetic nanoparticles has been demonstrated previously for diagnostic (B-mode) ultrasound imaging and shown to enhance gene delivery in vitro and in vivo. In the present work, passive acoustic mapping (PAM) was used to investigate the potential of magnetic microbubbles for localizing and enhancing cavitation activity under focused ultrasound. Suspensions of magnetic microbubbles consisting of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), air and 10 nm diameter iron oxide nanoparticles were injected into a tissue mimicking phantom at different flow velocities (from 0 to 50 mm s −1 ) with or without an applied magnetic field. Microbubbles were excited using a 500 kHz single element focused transducer at peak negative focal pressures of 0.1–1.0 MPa, while a 64 channel imaging array passively recorded their acoustic emissions. Magnetic localization of microbubble-induced cavitation activity was successfully achieved and could be resolved using PAM as a shift in the spatial distribution and increases in the intensity and sustainability of cavitation activity under the influence of a magnetic field. Under flow conditions at shear rates of up to 100 s −1 targeting efficacy was maintained. Application of a magnetic field was shown to consistently increase the energy of cavitation emissions by a factor of 2–5 times over the duration of exposures compared to the case without targeting, which was approximately equivalent to doubling the injected microbubble dose. These results suggest that magnetic targeting could be used to localize and increase the concentration of microbubbles and hence cavitation activity for a given systemic dose of microbubbles or ultrasound intensity. (paper)

  14. Technical note Flood map development by coupling satellite maps ...

    African Journals Online (AJOL)

    Flood maps are important for local authorities in designing mitigation plans to minimise damage and loss due to flooding. In recent years, flood events in the Sarawak River Basin, Malaysia have caused damage to property, loss of life and disruption of productive activities. Currently, the available flood map for Sarawak River ...

  15. Fixed point theorems in locally convex spaces—the Schauder mapping method

    Directory of Open Access Journals (Sweden)

    S. Cobzaş

    2006-03-01

    Full Text Available In the appendix to the book by F. F. Bonsal, Lectures on Some Fixed Point Theorems of Functional Analysis (Tata Institute, Bombay, 1962 a proof by Singbal of the Schauder-Tychonoff fixed point theorem, based on a locally convex variant of Schauder mapping method, is included. The aim of this note is to show that this method can be adapted to yield a proof of Kakutani fixed point theorem in the locally convex case. For the sake of completeness we include also the proof of Schauder-Tychonoff theorem based on this method. As applications, one proves a theorem of von Neumann and a minimax result in game theory.

  16. Spatial cluster analysis of nanoscopically mapped serotonin receptors for classification of fixed brain tissue

    Science.gov (United States)

    Sams, Michael; Silye, Rene; Göhring, Janett; Muresan, Leila; Schilcher, Kurt; Jacak, Jaroslaw

    2014-01-01

    We present a cluster spatial analysis method using nanoscopic dSTORM images to determine changes in protein cluster distributions within brain tissue. Such methods are suitable to investigate human brain tissue and will help to achieve a deeper understanding of brain disease along with aiding drug development. Human brain tissue samples are usually treated postmortem via standard fixation protocols, which are established in clinical laboratories. Therefore, our localization microscopy-based method was adapted to characterize protein density and protein cluster localization in samples fixed using different protocols followed by common fluorescent immunohistochemistry techniques. The localization microscopy allows nanoscopic mapping of serotonin 5-HT1A receptor groups within a two-dimensional image of a brain tissue slice. These nanoscopically mapped proteins can be confined to clusters by applying the proposed statistical spatial analysis. Selected features of such clusters were subsequently used to characterize and classify the tissue. Samples were obtained from different types of patients, fixed with different preparation methods, and finally stored in a human tissue bank. To verify the proposed method, samples of a cryopreserved healthy brain have been compared with epitope-retrieved and paraffin-fixed tissues. Furthermore, samples of healthy brain tissues were compared with data obtained from patients suffering from mental illnesses (e.g., major depressive disorder). Our work demonstrates the applicability of localization microscopy and image analysis methods for comparison and classification of human brain tissues at a nanoscopic level. Furthermore, the presented workflow marks a unique technological advance in the characterization of protein distributions in brain tissue sections.

  17. Learning process mapping heuristics under stochastic sampling overheads

    Science.gov (United States)

    Ieumwananonthachai, Arthur; Wah, Benjamin W.

    1991-01-01

    A statistical method was developed previously for improving process mapping heuristics. The method systematically explores the space of possible heuristics under a specified time constraint. Its goal is to get the best possible heuristics while trading between the solution quality of the process mapping heuristics and their execution time. The statistical selection method is extended to take into consideration the variations in the amount of time used to evaluate heuristics on a problem instance. The improvement in performance is presented using the more realistic assumption along with some methods that alleviate the additional complexity.

  18. How relevant is heterogeneous chemistry on Mars? Strong tests via global mapping of water and ozone (sampled via O2 dayglow)

    Science.gov (United States)

    Villanueva, Geronimo Luis; Mumma, Michael J.; Novak, Robert E.

    2015-11-01

    Ozone and water are powerful tracers of photochemical processes on Mars. Considering that water is a condensable with a multifaceted hydrological cycle and ozone is continuously being produced / destroyed on short-time scales, their maps can test the validity of current 3D photochemical and dynamical models. Comparisons of modern GCM models (e.g., Lefèvre et al. 2004) with certain datasets (e.g., Clancy et al. 2012; Bertaux et al. 2012) point to significant disagreement, which in some cases have been related to heterogeneous (gas-dust) chemistry beyond the classical gas-gas homogeneous reactions.We address these concerns by acquiring full 2D maps of water and ozone (via O2 dayglow) on Mars, employing high spectral infrared spectrometers at ground-based telescopes (CRIRES/VLT and CSHELL/NASA-IRTF). By performing a rotational analysis on the O2 lines, we derive molecular temperature maps that we use to derive the vertical level of the emission (e.g., Novak et al. 2002). Our maps sample the full observable disk of Mars on March/25/2008 (Ls=50°, northern winter) and on Jan/29/2014 (Ls=83°, northern spring). The maps reveal a strong dependence of the O2 emission and water burden on local orography, while the temperature maps are in strong disagreement with current models. Could this be the signature of heterogeneous chemistry? We will present the global maps and will discuss possible scenarios to explain the observations.This work was partially funded by grants from NASA's Planetary Astronomy Program (344-32-51-96), NASA’s Mars Fundamental Research Program (203959.02.02.20.29), NASA’s Astrobiology Program (344-53-51), and the NSF-RUI Program (AST-805540). We thank the administration and staff of the European Southern Observatory/VLT and NASA-IRTF for awarding observing time and coordinating our observations.Bertaux, J.-L., Gondet, B., Lefèvre, F., et al. 2012. J. Geophys. Res. Pl. 117. pp. 1-9.Clancy, R.T., Sandor, B.J., Wolff, M.J., et al. 2012. J. Geophys. Res

  19. A microarray-based genotyping and genetic mapping approach for highly heterozygous outcrossing species enables localization of a large fraction of the unassembled Populus trichocarpa genome sequence.

    Science.gov (United States)

    Drost, Derek R; Novaes, Evandro; Boaventura-Novaes, Carolina; Benedict, Catherine I; Brown, Ryan S; Yin, Tongming; Tuskan, Gerald A; Kirst, Matias

    2009-06-01

    Microarrays have demonstrated significant power for genome-wide analyses of gene expression, and recently have also revolutionized the genetic analysis of segregating populations by genotyping thousands of loci in a single assay. Although microarray-based genotyping approaches have been successfully applied in yeast and several inbred plant species, their power has not been proven in an outcrossing species with extensive genetic diversity. Here we have developed methods for high-throughput microarray-based genotyping in such species using a pseudo-backcross progeny of 154 individuals of Populus trichocarpa and P. deltoides analyzed with long-oligonucleotide in situ-synthesized microarray probes. Our analysis resulted in high-confidence genotypes for 719 single-feature polymorphism (SFP) and 1014 gene expression marker (GEM) candidates. Using these genotypes and an established microsatellite (SSR) framework map, we produced a high-density genetic map comprising over 600 SFPs, GEMs and SSRs. The abundance of gene-based markers allowed us to localize over 35 million base pairs of previously unplaced whole-genome shotgun (WGS) scaffold sequence to putative locations in the genome of P. trichocarpa. A high proportion of sampled scaffolds could be verified for their placement with independently mapped SSRs, demonstrating the previously un-utilized power that high-density genotyping can provide in the context of map-based WGS sequence reassembly. Our results provide a substantial contribution to the continued improvement of the Populus genome assembly, while demonstrating the feasibility of microarray-based genotyping in a highly heterozygous population. The strategies presented are applicable to genetic mapping efforts in all plant species with similarly high levels of genetic diversity.

  20. Simultaneous Localization and Mapping with Iterative Sparse Extended Information Filter for Autonomous Vehicles

    Directory of Open Access Journals (Sweden)

    Bo He

    2015-08-01

    Full Text Available In this paper, a novel iterative sparse extended information filter (ISEIF was proposed to solve the simultaneous localization and mapping problem (SLAM, which is very crucial for autonomous vehicles. The proposed algorithm solves the measurement update equations with iterative methods adaptively to reduce linearization errors. With the scalability advantage being kept, the consistency and accuracy of SEIF is improved. Simulations and practical experiments were carried out with both a land car benchmark and an autonomous underwater vehicle. Comparisons between iterative SEIF (ISEIF, standard EKF and SEIF are presented. All of the results convincingly show that ISEIF yields more consistent and accurate estimates compared to SEIF and preserves the scalability advantage over EKF, as well.

  1. Simultaneous Localization and Mapping with Iterative Sparse Extended Information Filter for Autonomous Vehicles.

    Science.gov (United States)

    He, Bo; Liu, Yang; Dong, Diya; Shen, Yue; Yan, Tianhong; Nian, Rui

    2015-08-13

    In this paper, a novel iterative sparse extended information filter (ISEIF) was proposed to solve the simultaneous localization and mapping problem (SLAM), which is very crucial for autonomous vehicles. The proposed algorithm solves the measurement update equations with iterative methods adaptively to reduce linearization errors. With the scalability advantage being kept, the consistency and accuracy of SEIF is improved. Simulations and practical experiments were carried out with both a land car benchmark and an autonomous underwater vehicle. Comparisons between iterative SEIF (ISEIF), standard EKF and SEIF are presented. All of the results convincingly show that ISEIF yields more consistent and accurate estimates compared to SEIF and preserves the scalability advantage over EKF, as well.

  2. Generating Multi-Destination Maps.

    Science.gov (United States)

    Zhang, Junsong; Fan, Jiepeng; Luo, Zhenshan

    2017-08-01

    Multi-destination maps are a kind of navigation maps aimed to guide visitors to multiple destinations within a region, which can be of great help to urban visitors. However, they have not been developed in the current online map service. To address this issue, we introduce a novel layout model designed especially for generating multi-destination maps, which considers the global and local layout of a multi-destination map. We model the layout problem as a graph drawing that satisfies a set of hard and soft constraints. In the global layout phase, we balance the scale factor between ROIs. In the local layout phase, we make all edges have good visibility and optimize the map layout to preserve the relative length and angle of roads. We also propose a perturbation-based optimization method to find an optimal layout in the complex solution space. The multi-destination maps generated by our system are potential feasible on the modern mobile devices and our result can show an overview and a detail view of the whole map at the same time. In addition, we perform a user study to evaluate the effectiveness of our method, and the results prove that the multi-destination maps achieve our goals well.

  3. Mapping face recognition information use across cultures

    Directory of Open Access Journals (Sweden)

    Sébastien eMiellet

    2013-02-01

    Full Text Available Face recognition is not rooted in a universal eye movement information-gathering strategy. Western observers favor a local facial feature sampling strategy, whereas Eastern observers prefer sampling face information from a global, central fixation strategy. Yet, the precise qualitative (the diagnostic and quantitative (the amount information underlying these cultural perceptual biases in face recognition remains undetermined.To this end, we monitored the eye movements of Western and Eastern observers during a face recognition task, with a novel gaze-contingent technique: the Expanding Spotlight. We used 2° Gaussian apertures centered on the observers' fixations expanding dynamically at a rate of 1° every 25ms at each fixation - the longer the fixation duration, the larger the aperture size. Identity-specific face information was only displayed within the Gaussian aperture; outside the aperture, an average face template was displayed to facilitate saccade planning. Thus, the Expanding Spotlight simultaneously maps out the facial information span at each fixation location.Data obtained with the Expanding Spotlight technique confirmed that Westerners extract more information from the eye region, whereas Easterners extract more information from the nose region. Interestingly, this quantitative difference was paired with a qualitative disparity. Retinal filters based on spatial frequency decomposition built from the fixations maps revealed that Westerners used local high-spatial frequency information sampling, covering all the features critical for effective face recognition (the eyes and the mouth. In contrast, Easterners achieved a similar result by using global low-spatial frequency information from those facial features.Our data show that the face system flexibly engages into local or global eye movement strategies across cultures, by relying on distinct facial information span and culturally tuned spatially filtered information. Overall, our

  4. The analytical calibration in (bio)imaging/mapping of the metallic elements in biological samples--definitions, nomenclature and strategies: state of the art.

    Science.gov (United States)

    Jurowski, Kamil; Buszewski, Bogusław; Piekoszewski, Wojciech

    2015-01-01

    Nowadays, studies related to the distribution of metallic elements in biological samples are one of the most important issues. There are many articles dedicated to specific analytical atomic spectrometry techniques used for mapping/(bio)imaging the metallic elements in various kinds of biological samples. However, in such literature, there is a lack of articles dedicated to reviewing calibration strategies, and their problems, nomenclature, definitions, ways and methods used to obtain quantitative distribution maps. The aim of this article was to characterize the analytical calibration in the (bio)imaging/mapping of the metallic elements in biological samples including (1) nomenclature; (2) definitions, and (3) selected and sophisticated, examples of calibration strategies with analytical calibration procedures applied in the different analytical methods currently used to study an element's distribution in biological samples/materials such as LA ICP-MS, SIMS, EDS, XRF and others. The main emphasis was placed on the procedures and methodology of the analytical calibration strategy. Additionally, the aim of this work is to systematize the nomenclature for the calibration terms: analytical calibration, analytical calibration method, analytical calibration procedure and analytical calibration strategy. The authors also want to popularize the division of calibration methods that are different than those hitherto used. This article is the first work in literature that refers to and emphasizes many different and complex aspects of analytical calibration problems in studies related to (bio)imaging/mapping metallic elements in different kinds of biological samples. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Value of epicardial potential maps in localizing pre-excitation sites for radiofrequency ablation. A simulation study

    Science.gov (United States)

    Hren, Rok

    1998-06-01

    Using computer simulations, we systematically investigated the limitations of an inverse solution that employs the potential distribution on the epicardial surface as an equivalent source model in localizing pre-excitation sites in Wolff-Parkinson-White syndrome. A model of the human ventricular myocardium that features an anatomically accurate geometry, an intramural rotating anisotropy and a computational implementation of the excitation process based on electrotonic interactions among cells, was used to simulate body surface potential maps (BSPMs) for 35 pre-excitation sites positioned along the atrioventricular ring. Two individualized torso models were used to account for variations in torso boundaries. Epicardial potential maps (EPMs) were computed using the L-curve inverse solution. The measure for accuracy of the localization was the distance between a position of the minimum in the inverse EPMs and the actual site of pre-excitation in the ventricular model. When the volume conductor properties and lead positions of the torso were precisely known and the measurement noise was added to the simulated BSPMs, the minimum in the inverse EPMs was at 12 ms after the onset on average within cm of the pre-excitation site. When the standard torso model was used to localize the sites of onset of the pre-excitation sequence initiated in individualized male and female torso models, the mean distance between the minimum and the pre-excitation site was cm for the male torso and cm for the female torso. The findings of our study indicate that a location of the minimum in EPMs computed using the inverse solution can offer non-invasive means for pre-interventional planning of the ablative treatment.

  6. Elemental mapping in scanning transmission electron microscopy

    International Nuclear Information System (INIS)

    Allen, L J; D'Alfonso, A J; Lugg, N R; Findlay, S D; LeBeau, J M; Stemmer, S

    2010-01-01

    We discuss atomic resolution chemical mapping in scanning transmission electron microscopy (STEM) based on core-loss electron energy loss spectroscopy (EELS) and also on energy dispersive X-ray (EDX) imaging. Chemical mapping using EELS can yield counterintuitive results which, however, can be understood using first principles calculations. Experimental chemical maps based on EDX bear out the thesis that such maps are always likely to be directly interpretable. This can be explained in terms of the local nature of the effective optical potential for ionization under those imaging conditions. This is followed by an excursion into the complementary technique of elemental mapping using energy-filtered transmission electron microscopy (EFTEM) in a conventional transmission electron microscope. We will then consider the widely used technique of Z-contrast or high-angle annular dark field (HAADF) imaging, which is based on phonon excitation, where it has recently been shown that intensity variations can be placed on an absolute scale by normalizing the measured intensities to the incident beam. Results, showing excellent agreement between theory and experiment to within a few percent, are shown for Z-contrast imaging from a sample of PbWO 4 .

  7. The usefulness of fractional anisotropy maps in localization of lacunar infractions in striatum, internal capsule and thalamus

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, H.K.; Lee, S.K.; Kim, D.I. [Dept. of Radiology and Research, Yonsei University Coll. of Medicine, Seoul (Korea); JHeo, J.H. [Dept. of Neurology, Yonsei University Coll. of Medicine, Seoul (Korea)

    2005-04-01

    We aimed in this study to assess the clinical usefulness of fractional anisotropy (FA) maps in the evaluation of lacunar infractions in striatum, internal capsule and thalamus. We retrospectively reviewed 28 patients (18 mean, 10 women; mean age 63 years) who had acute lacunar infraction in striatum, internal capsule and thalamus on diffusion weighted MR imaging (DWI). Fractional anisotropy (FA) maps were generated in addition to conventional T2 weigthed images (T2WI) and trace masp of DWI. Two radiologists reviewed the location of infraction was determined by FA maps. i.e. on the white band of internal capsule. Accuracy and inter-observer agreement on determination of the location of interfraction was evaluated. Accuracy of infract localization by T2WI-DWI only was varied from 72 to 91% according to the observers. Inter-observer agreement value was moderate (Kappa=0.446), when images were interpreted by T2WI-DWI only. Clinical manifestation of each lesions wre varied, but sensory motor stroke was mainly observed in thalamic lesion (50%) while pure motor hemiparesis was predominant in the case of infract involving internal capsule, corona radiata (91%) and basal ganglia (83%). The FA maps is useful in the evaluation of lacunar lesions in striatum, internal capsule and thalamus. Clinical presentation varies according to the exact location of lacunar infractions, and more accurate diagnosis can be made by FA maps as well as conventional T2-weighted image and DWI.

  8. Accelerated Enveloping Distribution Sampling: Enabling Sampling of Multiple End States while Preserving Local Energy Minima.

    Science.gov (United States)

    Perthold, Jan Walther; Oostenbrink, Chris

    2018-05-17

    Enveloping distribution sampling (EDS) is an efficient approach to calculate multiple free-energy differences from a single molecular dynamics (MD) simulation. However, the construction of an appropriate reference-state Hamiltonian that samples all states efficiently is not straightforward. We propose a novel approach for the construction of the EDS reference-state Hamiltonian, related to a previously described procedure to smoothen energy landscapes. In contrast to previously suggested EDS approaches, our reference-state Hamiltonian preserves local energy minima of the combined end-states. Moreover, we propose an intuitive, robust and efficient parameter optimization scheme to tune EDS Hamiltonian parameters. We demonstrate the proposed method with established and novel test systems and conclude that our approach allows for the automated calculation of multiple free-energy differences from a single simulation. Accelerated EDS promises to be a robust and user-friendly method to compute free-energy differences based on solid statistical mechanics.

  9. Circle Maps and C*-algebras

    DEFF Research Database (Denmark)

    Schmidt, Thomas Lundsgaard; Thomsen, Klaus

    2015-01-01

    We consider a construction of $C^*$-algebras from continuous piecewise monotone maps on the circle which generalizes the crossed product construction for homeomorphisms and more generally the construction of Renault, Deaconu and Anantharaman-Delaroche for local homeomorphisms. Assuming that the map...... is surjective and not locally injective we give necessary and sufficient conditions for the simplicity of the $C^*$-algebra and show that it is then a Kirchberg algebra. We provide tools for the calculation of the K-theory groups and turn them into an algorithmic method for Markov maps....

  10. Assessment and application of national environmental databases and mapping tools at the local level to two community case studies.

    Science.gov (United States)

    Hammond, Davyda; Conlon, Kathryn; Barzyk, Timothy; Chahine, Teresa; Zartarian, Valerie; Schultz, Brad

    2011-03-01

    Communities are concerned over pollution levels and seek methods to systematically identify and prioritize the environmental stressors in their communities. Geographic information system (GIS) maps of environmental information can be useful tools for communities in their assessment of environmental-pollution-related risks. Databases and mapping tools that supply community-level estimates of ambient concentrations of hazardous pollutants, risk, and potential health impacts can provide relevant information for communities to understand, identify, and prioritize potential exposures and risk from multiple sources. An assessment of existing databases and mapping tools was conducted as part of this study to explore the utility of publicly available databases, and three of these databases were selected for use in a community-level GIS mapping application. Queried data from the U.S. EPA's National-Scale Air Toxics Assessment, Air Quality System, and National Emissions Inventory were mapped at the appropriate spatial and temporal resolutions for identifying risks of exposure to air pollutants in two communities. The maps combine monitored and model-simulated pollutant and health risk estimates, along with local survey results, to assist communities with the identification of potential exposure sources and pollution hot spots. Findings from this case study analysis will provide information to advance the development of new tools to assist communities with environmental risk assessments and hazard prioritization. © 2010 Society for Risk Analysis.

  11. A consensus linkage map of lentil based on DArT markers from three RIL mapping populations.

    Directory of Open Access Journals (Sweden)

    Duygu Ates

    Full Text Available Lentil (Lens culinaris ssp. culinaris Medikus is a diploid (2n = 2x = 14, self-pollinating grain legume with a haploid genome size of about 4 Gbp and is grown throughout the world with current annual production of 4.9 million tonnes.A consensus map of lentil (Lens culinaris ssp. culinaris Medikus was constructed using three different lentils recombinant inbred line (RIL populations, including "CDC Redberry" x "ILL7502" (LR8, "ILL8006" x "CDC Milestone" (LR11 and "PI320937" x "Eston" (LR39.The lentil consensus map was composed of 9,793 DArT markers, covered a total of 977.47 cM with an average distance of 0.10 cM between adjacent markers and constructed 7 linkage groups representing 7 chromosomes of the lentil genome. The consensus map had no gap larger than 12.67 cM and only 5 gaps were found to be between 12.67 cM and 6.0 cM (on LG3 and LG4. The localization of the SNP markers on the lentil consensus map were in general consistent with their localization on the three individual genetic linkage maps and the lentil consensus map has longer map length, higher marker density and shorter average distance between the adjacent markers compared to the component linkage maps.This high-density consensus map could provide insight into the lentil genome. The consensus map could also help to construct a physical map using a Bacterial Artificial Chromosome library and map based cloning studies. Sequence information of DArT may help localization of orientation scaffolds from Next Generation Sequencing data.

  12. A consensus linkage map of lentil based on DArT markers from three RIL mapping populations.

    Science.gov (United States)

    Ates, Duygu; Aldemir, Secil; Alsaleh, Ahmad; Erdogmus, Semih; Nemli, Seda; Kahriman, Abdullah; Ozkan, Hakan; Vandenberg, Albert; Tanyolac, Bahattin

    2018-01-01

    Lentil (Lens culinaris ssp. culinaris Medikus) is a diploid (2n = 2x = 14), self-pollinating grain legume with a haploid genome size of about 4 Gbp and is grown throughout the world with current annual production of 4.9 million tonnes. A consensus map of lentil (Lens culinaris ssp. culinaris Medikus) was constructed using three different lentils recombinant inbred line (RIL) populations, including "CDC Redberry" x "ILL7502" (LR8), "ILL8006" x "CDC Milestone" (LR11) and "PI320937" x "Eston" (LR39). The lentil consensus map was composed of 9,793 DArT markers, covered a total of 977.47 cM with an average distance of 0.10 cM between adjacent markers and constructed 7 linkage groups representing 7 chromosomes of the lentil genome. The consensus map had no gap larger than 12.67 cM and only 5 gaps were found to be between 12.67 cM and 6.0 cM (on LG3 and LG4). The localization of the SNP markers on the lentil consensus map were in general consistent with their localization on the three individual genetic linkage maps and the lentil consensus map has longer map length, higher marker density and shorter average distance between the adjacent markers compared to the component linkage maps. This high-density consensus map could provide insight into the lentil genome. The consensus map could also help to construct a physical map using a Bacterial Artificial Chromosome library and map based cloning studies. Sequence information of DArT may help localization of orientation scaffolds from Next Generation Sequencing data.

  13. Local connectome phenotypes predict social, health, and cognitive factors

    Directory of Open Access Journals (Sweden)

    Michael A. Powell

    2018-03-01

    Full Text Available The unique architecture of the human connectome is defined initially by genetics and subsequently sculpted over time with experience. Thus, similarities in predisposition and experience that lead to similarities in social, biological, and cognitive attributes should also be reflected in the local architecture of white matter fascicles. Here we employ a method known as local connectome fingerprinting that uses diffusion MRI to measure the fiber-wise characteristics of macroscopic white matter pathways throughout the brain. This fingerprinting approach was applied to a large sample (N = 841 of subjects from the Human Connectome Project, revealing a reliable degree of between-subject correlation in the local connectome fingerprints, with a relatively complex, low-dimensional substructure. Using a cross-validated, high-dimensional regression analysis approach, we derived local connectome phenotype (LCP maps that could reliably predict a subset of subject attributes measured, including demographic, health, and cognitive measures. These LCP maps were highly specific to the attribute being predicted but also sensitive to correlations between attributes. Collectively, these results indicate that the local architecture of white matter fascicles reflects a meaningful portion of the variability shared between subjects along several dimensions. The local connectome is the pattern of fiber systems (i.e., number of fibers, orientation, and size within a voxel, and it reflects the proximal characteristics of white matter fascicles distributed throughout the brain. Here we show how variability in the local connectome is correlated in a principled way across individuals. This intersubject correlation is reliable enough that unique phenotype maps can be learned to predict between-subject variability in a range of social, health, and cognitive attributes. This work shows, for the first time, how the local connectome has both the sensitivity and the specificity to

  14. Imaging of Caenorhabditis elegans samples and sub-cellular localization of new generation photosensitizers for photodynamic therapy, using non-linear microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Filippidis, G [Institute of Electronic Structure and Laser, Foundation of Research and Technology-Hellas, PO Box 1527, 71110 Heraklion (Greece); Kouloumentas, C [Institute of Electronic Structure and Laser, Foundation of Research and Technology-Hellas, PO Box 1527, 71110 Heraklion (Greece); Kapsokalyvas, D [Institute of Electronic Structure and Laser, Foundation of Research and Technology-Hellas, PO Box 1527, 71110 Heraklion (Greece); Voglis, G [Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology, Heraklion 71110, Crete (Greece); Tavernarakis, N [Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology, Heraklion 71110, Crete (Greece); Papazoglou, T G [Institute of Electronic Structure and Laser, Foundation of Research and Technology-Hellas, PO Box 1527, 71110 Heraklion (Greece)

    2005-08-07

    Two-photon excitation fluorescence (TPEF) and second-harmonic generation (SHG) are relatively new promising tools for the imaging and mapping of biological structures and processes at the microscopic level. The combination of the two image-contrast modes in a single instrument can provide unique and complementary information concerning the structure and the function of tissues and individual cells. The extended application of this novel, innovative technique by the biological community is limited due to the high price of commercial multiphoton microscopes. In this study, a compact, inexpensive and reliable setup utilizing femtosecond pulses for excitation was developed for the TPEF and SHG imaging of biological samples. Specific cell types of the nematode Caenorhabditis elegans were imaged. Detection of the endogenous structural proteins of the worm, which are responsible for observation of SHG signals, was achieved. Additionally, the binding of different photosensitizers in the HL-60 cell line was investigated, using non-linear microscopy. The sub-cellular localization of photosensitizers of a new generation, very promising for photodynamic therapy (PDT) (Hypericum perforatum L. extracts) was achieved. The sub-cellular localization of these novel photosensitizers was linked with their photodynamic action during PDT, and the possible mechanisms for cell killing have been elucidated.

  15. Ordered and isomorphic mapping of periodic structures in the parametrically forced logistic map

    Energy Technology Data Exchange (ETDEWEB)

    Maranhão, Dariel M., E-mail: dariel@ifsp.edu.br [Departamento de Ciências e Matemática, Instituto Federal de Educação, Ciência e Tecnologia de São Paulo, São Paulo (Brazil); Diretoria de Informática, Universidade Nove de Julho, São Paulo (Brazil)

    2016-09-23

    Highlights: • A direct description of the internal structure of a periodic window in terms of winding numbers is proposed. • Periodic structures in parameter spaces are mapped in a recurrent and isomorphic way. • Sequences of winding numbers show global and local organization of periodic domains. - Abstract: We investigate the periodic domains found in the parametrically forced logistic map, the classical logistic map when its control parameter changes dynamically. Phase diagrams in two-parameter spaces reveal intricate periodic structures composed of patterns of intersecting superstable orbits curves, defining the cell of a periodic window. Cells appear multifoliated and ordered, and they are isomorphically mapped when one changes the map parameters. Also, we identify the characteristics of simplest cell and apply them to other more complex, discussing how the topography on parameter space is affected. By use of the winding number as defined in periodically forced oscillators, we show that the hierarchical organization of the periodic domains is manifested in global and local scales.

  16. Analyzing thematic maps and mapping for accuracy

    Science.gov (United States)

    Rosenfield, G.H.

    1982-01-01

    Two problems which exist while attempting to test the accuracy of thematic maps and mapping are: (1) evaluating the accuracy of thematic content, and (2) evaluating the effects of the variables on thematic mapping. Statistical analysis techniques are applicable to both these problems and include techniques for sampling the data and determining their accuracy. In addition, techniques for hypothesis testing, or inferential statistics, are used when comparing the effects of variables. A comprehensive and valid accuracy test of a classification project, such as thematic mapping from remotely sensed data, includes the following components of statistical analysis: (1) sample design, including the sample distribution, sample size, size of the sample unit, and sampling procedure; and (2) accuracy estimation, including estimation of the variance and confidence limits. Careful consideration must be given to the minimum sample size necessary to validate the accuracy of a given. classification category. The results of an accuracy test are presented in a contingency table sometimes called a classification error matrix. Usually the rows represent the interpretation, and the columns represent the verification. The diagonal elements represent the correct classifications. The remaining elements of the rows represent errors by commission, and the remaining elements of the columns represent the errors of omission. For tests of hypothesis that compare variables, the general practice has been to use only the diagonal elements from several related classification error matrices. These data are arranged in the form of another contingency table. The columns of the table represent the different variables being compared, such as different scales of mapping. The rows represent the blocking characteristics, such as the various categories of classification. The values in the cells of the tables might be the counts of correct classification or the binomial proportions of these counts divided by

  17. A novel chaotic particle swarm optimization approach using Henon map and implicit filtering local search for economic load dispatch

    International Nuclear Information System (INIS)

    Coelho, Leandro dos Santos; Mariani, Viviana Cocco

    2009-01-01

    Particle swarm optimization (PSO) is a population-based swarm intelligence algorithm driven by the simulation of a social psychological metaphor instead of the survival of the fittest individual. Based on the chaotic systems theory, this paper proposed a novel chaotic PSO combined with an implicit filtering (IF) local search method to solve economic dispatch problems. Since chaotic mapping enjoys certainty, ergodicity and the stochastic property, the proposed PSO introduces chaos mapping using Henon map sequences which increases its convergence rate and resulting precision. The chaotic PSO approach is used to produce good potential solutions, and the IF is used to fine-tune of final solution of PSO. The hybrid methodology is validated for a test system consisting of 13 thermal units whose incremental fuel cost function takes into account the valve-point loading effects. Simulation results are promising and show the effectiveness of the proposed approach.

  18. A survey of simultaneous localization and mapping on unstructured lunar complex environment

    Science.gov (United States)

    Wang, Yiqiao; Zhang, Wei; An, Pei

    2017-10-01

    Simultaneous localization and mapping (SLAM) technology is the key to realizing lunar rover's intelligent perception and autonomous navigation. It embodies the autonomous ability of mobile robot, and has attracted plenty of concerns of researchers in the past thirty years. Visual sensors are meaningful to SLAM research because they can provide a wealth of information. Visual SLAM uses merely images as external information to estimate the location of the robot and construct the environment map. Nowadays, SLAM technology still has problems when applied in large-scale, unstructured and complex environment. Based on the latest technology in the field of visual SLAM, this paper investigates and summarizes the SLAM technology using in the unstructured complex environment of lunar surface. In particular, we focus on summarizing and comparing the detection and matching of features of SIFT, SURF and ORB, in the meanwhile discussing their advantages and disadvantages. We have analyzed the three main methods: SLAM Based on Extended Kalman Filter, SLAM Based on Particle Filter and SLAM Based on Graph Optimization (EKF-SLAM, PF-SLAM and Graph-based SLAM). Finally, this article summarizes and discusses the key scientific and technical difficulties in the lunar context that Visual SLAM faces. At the same time, we have explored the frontier issues such as multi-sensor fusion SLAM and multi-robot cooperative SLAM technology. We also predict and prospect the development trend of lunar rover SLAM technology, and put forward some ideas of further research.

  19. Analyses of Gas, Steam and Water Samples Collected in and Around Lassen Volcanic National Park, California, 1975-2002

    Science.gov (United States)

    Janik, Cathy J.; Bergfeld, D.

    2010-01-01

    This report contains physical and chemical data from gas, steam, and water samples collected between July 1975 and September 2002 from locations in and around Lassen Volcanic National Park, California. Data are compiled as tables in Excel spreadsheets and are organized by locale. Most data are keyed to 1 of 107 site codes that are shown on local- and regional-scale maps. Brief descriptions of terminology, sampling, and analytical methods are provided.

  20. A map of the universe

    Energy Technology Data Exchange (ETDEWEB)

    Gott III, J. Richard; Juric, Mario; Schlegel, David; Hoyle, Fiona; Vogeley, Michael; Tegmark, Max; Bahcall, Neta; Brinkmann, Jon

    2003-10-20

    We have produced a new conformal map of the universe illustrating recent discoveries, ranging from Kuiper belt objects in the Solar system, to the galaxies and quasars from the Sloan Digital Sky Survey. This map projection, based on the logarithm map of the complex plane, preserves shapes locally, and yet is able to display the entire range of astronomical scales from the Earth s neighborhood to the cosmic microwave background. The conformal nature of the projection, preserving shapes locally, may be of particular use for analyzing large scale structure. Prominent in the map is a Sloan Great Wall of galaxies 1.37 billion light years long, 80 percent longer than the Great Wall discovered by Geller and Huchra and therefore the largest observed structure in the universe.

  1. Investigating the origins of double photopeaks in CsI:Tl samples through activator mapping

    Science.gov (United States)

    Onken, Drew R.; Gridin, Sergii; Williams, Richard T.; Williams, Charles B.; Donati, George L.; Gayshan, Vadim; Vasyukov, Sergey; Gektin, Alex

    2018-06-01

    Careful examination of the origins of double photopeaks in CsI:Tl provides a foundation for exploring the relationship between activator homogeneity and photopeak resolution in scintillators. In rare cases, certain CsI:Tl crystals exhibit a second photopeak in the pulse-height spectrum. A combination of optical mapping and ICP-MS measurements reveals the presence of two distinct regions with differing Tl concentrations in these crystals. The oscillator strength of the 299 nm absorption A-band of Tl in CsI was measured to be 0.0526 ± 0.0008; this parameter can be used to quantify activator concentration from the optical absorption. Using published measurements of luminescence intensity versus Tl concentration, the distributions of Tl measured from optical absorption maps of the samples were reconstructed into photopeaks in good agreement with experiment. The distribution of Tl concentrations in these particular crystals allowed examining luminescence pulse shape as a function of Tl concentration.

  2. Performance Analysis of the Microsoft Kinect Sensor for 2D Simultaneous Localization and Mapping (SLAM Techniques

    Directory of Open Access Journals (Sweden)

    Kamarulzaman Kamarudin

    2014-12-01

    Full Text Available This paper presents a performance analysis of two open-source, laser scanner-based Simultaneous Localization and Mapping (SLAM techniques (i.e., Gmapping and Hector SLAM using a Microsoft Kinect to replace the laser sensor. Furthermore, the paper proposes a new system integration approach whereby a Linux virtual machine is used to run the open source SLAM algorithms. The experiments were conducted in two different environments; a small room with no features and a typical office corridor with desks and chairs. Using the data logged from real-time experiments, each SLAM technique was simulated and tested with different parameter settings. The results show that the system is able to achieve real time SLAM operation. The system implementation offers a simple and reliable way to compare the performance of Windows-based SLAM algorithm with the algorithms typically implemented in a Robot Operating System (ROS. The results also indicate that certain modifications to the default laser scanner-based parameters are able to improve the map accuracy. However, the limited field of view and range of Kinect’s depth sensor often causes the map to be inaccurate, especially in featureless areas, therefore the Kinect sensor is not a direct replacement for a laser scanner, but rather offers a feasible alternative for 2D SLAM tasks.

  3. Mapping local and global variability in plant trait distributions

    Energy Technology Data Exchange (ETDEWEB)

    Butler, Ethan E.; Datta, Abhirup; Flores-Moreno, Habacuc; Chen, Ming; Wythers, Kirk R.; Fazayeli, Farideh; Banerjee, Arindam; Atkin, Owen K.; Kattge, Jens; Amiaud, Bernard; Blonder, Benjamin; Boenisch, Gerhard; Bond-Lamberty, Ben; Brown, Kerry A.; Byun, Chaeho; Campetella, Giandiego; Cerabolini, Bruno E. L.; Cornelissen, Johannes H. C.; Craine, Joseph M.; Craven, Dylan; de Vries, Franciska T.; Díaz, Sandra; Domingues, Tomas F.; Forey, Estelle; González-Melo, Andrés; Gross, Nicolas; Han, Wenxuan; Hattingh, Wesley N.; Hickler, Thomas; Jansen, Steven; Kramer, Koen; Kraft, Nathan J. B.; Kurokawa, Hiroko; Laughlin, Daniel C.; Meir, Patrick; Minden, Vanessa; Niinemets, Ülo; Onoda, Yusuke; Peñuelas, Josep; Read, Quentin; Sack, Lawren; Schamp, Brandon; Soudzilovskaia, Nadejda A.; Spasojevic, Marko J.; Sosinski, Enio; Thornton, Peter E.; Valladares, Fernando; van Bodegom, Peter M.; Williams, Mathew; Wirth, Christian; Reich, Peter B.

    2017-12-01

    Accurate trait-environment relationships and global maps of plant trait distributions represent a needed stepping stone in global biogeography and are critical constraints of key parameters for land models. Here, we use a global data set of plant traits to map trait distributions closely coupled to photosynthesis and foliar respiration: specific leaf area (SLA), and dry mass-based concentrations of leaf nitrogen (Nm) and phosphorus (Pm); We propose two models to extrapolate geographically sparse point data to continuous spatial surfaces. The first is a categorical model using species mean trait values, categorized into plant functional types (PFTs) and extrapolating to PFT occurrence ranges identified by remote sensing. The second is a Bayesian spatial model that incorporates information about PFT, location and environmental covariates to estimate trait distributions. Both models are further stratified by varying the number of PFTs; The performance of the models was evaluated based on their explanatory and predictive ability. The Bayesian spatial model leveraging the largest number of PFTs produced the best maps; The interpolation of full trait distributions enables a wider diversity of vegetation to be represented across the land surface. These maps may be used as input to Earth System Models and to evaluate other estimates of functional diversity.

  4. Geostatistics for Mapping Leaf Area Index over a Cropland Landscape: Efficiency Sampling Assessment

    Directory of Open Access Journals (Sweden)

    Javier Garcia-Haro

    2010-11-01

    Full Text Available This paper evaluates the performance of spatial methods to estimate leaf area index (LAI fields from ground-based measurements at high-spatial resolution over a cropland landscape. Three geostatistical model variants of the kriging technique, the ordinary kriging (OK, the collocated cokriging (CKC and kriging with an external drift (KED are used. The study focused on the influence of the spatial sampling protocol, auxiliary information, and spatial resolution in the estimates. The main advantage of these models lies in the possibility of considering the spatial dependence of the data and, in the case of the KED and CKC, the auxiliary information for each location used for prediction purposes. A high-resolution NDVI image computed from SPOT TOA reflectance data is used as an auxiliary variable in LAI predictions. The CKC and KED predictions have proven the relevance of the auxiliary information to reproduce the spatial pattern at local scales, proving the KED model to be the best estimator when a non-stationary trend is observed. Advantages and limitations of the methods in LAI field predictions for two systematic and two stratified spatial samplings are discussed for high (20 m, medium (300 m and coarse (1 km spatial scales. The KED has exhibited the best observed local accuracy for all the spatial samplings. Meanwhile, the OK model provides comparable results when a well stratified sampling scheme is considered by land cover.

  5. An adaptive scheme for robot localization and mapping with dynamically configurable inter-beacon range measurements.

    Science.gov (United States)

    Torres-González, Arturo; Martinez-de Dios, Jose Ramiro; Ollero, Anibal

    2014-04-25

    This work is motivated by robot-sensor network cooperation techniques where sensor nodes (beacons) are used as landmarks for range-only (RO) simultaneous localization and mapping (SLAM). This paper presents a RO-SLAM scheme that actuates over the measurement gathering process using mechanisms that dynamically modify the rate and variety of measurements that are integrated in the SLAM filter. It includes a measurement gathering module that can be configured to collect direct robot-beacon and inter-beacon measurements with different inter-beacon depth levels and at different rates. It also includes a supervision module that monitors the SLAM performance and dynamically selects the measurement gathering configuration balancing SLAM accuracy and resource consumption. The proposed scheme has been applied to an extended Kalman filter SLAM with auxiliary particle filters for beacon initialization (PF-EKF SLAM) and validated with experiments performed in the CONET Integrated Testbed. It achieved lower map and robot errors (34% and 14%, respectively) than traditional methods with a lower computational burden (16%) and similar beacon energy consumption.

  6. LiDAR-based 2D Localization and Mapping System using Elliptical Distance Correction Models for UAV Wind Turbine Blade Inspection

    DEFF Research Database (Denmark)

    Nikolov, Ivan Adriyanov; Madsen, Claus B.

    2017-01-01

    for on-site outdoor localization and mapping in low feature environment using the inexpensive RPLIDAR and an 9-DOF IMU. Our algorithm geometrically simplifies the wind turbine blade 2D cross-section to an elliptical model and uses it for distance and shape correction. We show that the proposed algorithm...

  7. Regional geochemical maps of the Tonopah 1 degree by 2 degrees Quadrangle, Nevada, based on samples of stream sediment and nonmagnetic heavy-mineral concentrate

    Science.gov (United States)

    Nash, J.T.; Siems, D.F.

    1988-01-01

    This report is part of a series of geologic, geochemical, and geophysical maps of the Tonopah 1° x 2° quadrangle, Nevada, prepared during studies of the area for the Conterminous United States Mineral Assessment Program (CUSMAP). Included here are 21 maps showing the distributions of selected elements or combinations of elements. These regional geochemical maps are based on chemical analyses of the minus-60 mesh (0.25 mm) fraction of stream-sediment samples and the nonmagnetic heavy-mineral concentrate derived from stream sediment. Stream sediments were collected at 1,217 sites. Our geochemical studies of mineralized rock samples provide a framework for evaluating the results from stream sediments.

  8. Generating a Danish raster-based topsoil property map combining choropleth maps and point information

    DEFF Research Database (Denmark)

    Greve, Mogens H.; Greve, Mette B.; Bøcher, Peder K.

    2007-01-01

    The Danish environmental authorities have posed a soil type dependent restriction on the application of nitrogen. The official Danish soil map is a choropleth topsoil map classifying the agricultural land into eight classes. The use of the soil map has shown that the maps have serious...... classification flaws. The objective of this work is to compile a continuous national topsoil texture map to replace the old topsoil map. Approximately 45,000 point samples were interpolated using ordinary kriging in 250 m x 250 m cells. To reduce variability and to obtain more homogeneous strata, the samples...... were stratified according to landscape types. Five new soil texture maps were compiled; one for each of the five textural classes, and a new categorical soil type map was compiled using the old classification system. Both the old choropleth map and the new continuous soil maps were compared to 354...

  9. Presurgical mapping with functional MRI. Comparative study with transcranial magnetic stimulation and intraoperative mapping

    Energy Technology Data Exchange (ETDEWEB)

    Kaminogo, Makio; Morikawa, Minoru; Ishimaru, Hideki; Ochi, Makoto; Onizuka, Masanori; Shirakawa, Yasushi; Takahashi, Haruki; Shibata, Shobu [Nagasaki Univ. (Japan). School of Medicine

    1999-05-01

    The thumb movement was evoked by transcranical magnetic stimulation (TCS) for the mapping of the motor cortex. After the placement of the marker determined by TCS on the scalp, fMRI under motor tasks consisting of repetitive grasping was performed. For motor cortex activation, an axial oblique plane to maximize gray matter sampling in the rolandic cortex was employed in order to compare these different mapping techniques more precisely. Sixteen patients with brain tumors were included in this study. In nine patients, fMRI disclosed activation in one restricted gyrus or in the localized area around one restricted sulcus. Of these nine patients, preoperative TCS mapping corresponded closely with fMRI in six, while in the remaining three, the TCS marker fell between 1 and 2 cm apart from the fMRI-activated area. However, in these three patients, intraoperative electrocortical stimulation corresponded with the preoperative mapping with fMRI. In six patients, contiguous two gyri were activated by motor tasks. The TCS marker was disclosed on one of the two activated gyri. Of these six patients, the position of the TCS marker and fMRI-activated site corresponded with each other in four cases. They were found on the same gyrus but there was 1.0-2.0 cm distance between them in two cases. Intraoperative somatosensory evoked potential was monitored in two of these six cases. They corresponded well with the mapping by fMRI and TCS together. In only one patient, no significant activation area was obtained by fMRI because of excessive head motion during motor tasks. The TCS maker in this patients was identical with intraoperative electro-cortical stimulation mapping. (K.H.)

  10. Presurgical mapping with functional MRI. Comparative study with transcranial magnetic stimulation and intraoperative mapping

    International Nuclear Information System (INIS)

    Kaminogo, Makio; Morikawa, Minoru; Ishimaru, Hideki; Ochi, Makoto; Onizuka, Masanori; Shirakawa, Yasushi; Takahashi, Haruki; Shibata, Shobu

    1999-01-01

    The thumb movement was evoked by transcranical magnetic stimulation (TCS) for the mapping of the motor cortex. After the placement of the marker determined by TCS on the scalp, fMRI under motor tasks consisting of repetitive grasping was performed. For motor cortex activation, an axial oblique plane to maximize gray matter sampling in the rolandic cortex was employed in order to compare these different mapping techniques more precisely. Sixteen patients with brain tumors were included in this study. In nine patients, fMRI disclosed activation in one restricted gyrus or in the localized area around one restricted sulcus. Of these nine patients, preoperative TCS mapping corresponded closely with fMRI in six, while in the remaining three, the TCS marker fell between 1 and 2 cm apart from the fMRI-activated area. However, in these three patients, intraoperative electrocortical stimulation corresponded with the preoperative mapping with fMRI. In six patients, contiguous two gyri were activated by motor tasks. The TCS marker was disclosed on one of the two activated gyri. Of these six patients, the position of the TCS marker and fMRI-activated site corresponded with each other in four cases. They were found on the same gyrus but there was 1.0-2.0 cm distance between them in two cases. Intraoperative somatosensory evoked potential was monitored in two of these six cases. They corresponded well with the mapping by fMRI and TCS together. In only one patient, no significant activation area was obtained by fMRI because of excessive head motion during motor tasks. The TCS maker in this patients was identical with intraoperative electro-cortical stimulation mapping. (K.H.)

  11. BAC-HAPPY mapping (BAP mapping: a new and efficient protocol for physical mapping.

    Directory of Open Access Journals (Sweden)

    Giang T H Vu

    2010-02-01

    Full Text Available Physical and linkage mapping underpin efforts to sequence and characterize the genomes of eukaryotic organisms by providing a skeleton framework for whole genome assembly. Hitherto, linkage and physical "contig" maps were generated independently prior to merging. Here, we develop a new and easy method, BAC HAPPY MAPPING (BAP mapping, that utilizes BAC library pools as a HAPPY mapping panel together with an Mbp-sized DNA panel to integrate the linkage and physical mapping efforts into one pipeline. Using Arabidopsis thaliana as an exemplar, a set of 40 Sequence Tagged Site (STS markers spanning approximately 10% of chromosome 4 were simultaneously assembled onto a BAP map compiled using both a series of BAC pools each comprising 0.7x genome coverage and dilute (0.7x genome samples of sheared genomic DNA. The resultant BAP map overcomes the need for polymorphic loci to separate genetic loci by recombination and allows physical mapping in segments of suppressed recombination that are difficult to analyze using traditional mapping techniques. Even virtual "BAC-HAPPY-mapping" to convert BAC landing data into BAC linkage contigs is possible.

  12. Distributed autonomous mapping of indoor environments

    Science.gov (United States)

    Rogers, J.; Paluri, M.; Cunningham, A.; Christensen, H. I.; Michael, N.; Kumar, V.; Ma, J.; Matthies, L.

    2011-06-01

    This paper describes the results of a Joint Experiment performed on behalf of the MAST CTA. The system developed for the Joint Experiment makes use of three robots which work together to explore and map an unknown environment. Each of the robots used in this experiment is equipped with a laser scanner for measuring walls and a camera for locating doorways. Information from both of these types of structures is concurrently incorporated into each robot's local map using a graph based SLAM technique. A Distributed-Data-Fusion algorithm is used to efficiently combine local maps from each robot into a shared global map. Each robot computes a compressed local feature map and transmits it to neighboring robots, which allows each robot to merge its map with the maps of its neighbors. Each robot caches the compressed maps from its neighbors, allowing it to maintain a coherent map with a common frame of reference. The robots utilize an exploration strategy to efficiently cover the unknown environment which allows collaboration on an unreliable communications channel. As each new branching point is discovered by a robot, it broadcasts the information about where this point is along with the robot's path from a known landmark to the other robots. When the next robot reaches a dead-end, new branching points are allocated by auction. In the event of communication interruption, the robot which observed the branching point will eventually explore it; therefore, the exploration is complete in the face of communication failure.

  13. A fixed point theorem for uniformly locally contractive mappings in a C-chainable cone rectangular metric space

    Directory of Open Access Journals (Sweden)

    Bessem Samet

    2011-09-01

    Full Text Available Recently, Azam, Arshad and Beg [ Banach contraction principle on cone rectangular metric spaces, Appl. Anal. Discrete Math. 2009] introduced the notion of cone rectangular metric spaces by replacing the triangular inequality of a cone metric space by a rectangular inequality. In this paper, we introduce the notion of c-chainable cone rectangular metric space and we establish a fixed point theorem for uniformly locally contractive mappings in such spaces. An example is given to illustrate our obtained result.

  14. Vaccination with peptides of Mycobacterium avium subsp. paratuberculosis (MAP) reduces MAP burden of infected goats

    DEFF Research Database (Denmark)

    Melvang, Heidi Mikkelsen; Hassan, Sufia Butt; Thakur, Aneesh

    Mycobacterium avium subsp. paratuberculosis (Map) is the cause of paratuberculosis, a chronic enteritis of ruminants that is widespread worldwide. We investigated the effect of post-exposure vaccination with Map specific peptides in a goat model aiming at developing a Map vaccine that will neither...... unique to Map from selected proteins (n =68). For vaccination, 23 MAP peptides (20 µg each) were selected and formulated with Montanide ISA 61 VG adjuvant. At age three weeks 10 goats were orally inoculated with 4x10E9 live Map and assigned to two groups of 5 goats each: 5 vaccinated (V) at 14 and 18...... weeks post inoculation (PI) and 5 unvaccinated (C). At termination 32 weeks PI, Map burdens in 15 intestinal tissues and lymph nodes were determined by IS900 qPCR. Of the 75 tissue samples from the 5 C goats only 5 samples were IS900 qPCR negative. In contrast, only 9 samples in total from 5 V goats...

  15. Investigating the tradeoffs between spatial resolution and diffusion sampling for brain mapping with diffusion tractography: time well spent?

    Science.gov (United States)

    Calabrese, Evan; Badea, Alexandra; Coe, Christopher L; Lubach, Gabriele R; Styner, Martin A; Johnson, G Allan

    2014-11-01

    Interest in mapping white matter pathways in the brain has peaked with the recognition that altered brain connectivity may contribute to a variety of neurologic and psychiatric diseases. Diffusion tractography has emerged as a popular method for postmortem brain mapping initiatives, including the ex-vivo component of the human connectome project, yet it remains unclear to what extent computer-generated tracks fully reflect the actual underlying anatomy. Of particular concern is the fact that diffusion tractography results vary widely depending on the choice of acquisition protocol. The two major acquisition variables that consume scan time, spatial resolution, and diffusion sampling, can each have profound effects on the resulting tractography. In this analysis, we determined the effects of the temporal tradeoff between spatial resolution and diffusion sampling on tractography in the ex-vivo rhesus macaque brain, a close primate model for the human brain. We used the wealth of autoradiography-based connectivity data available for the rhesus macaque brain to assess the anatomic accuracy of six time-matched diffusion acquisition protocols with varying balance between spatial and diffusion sampling. We show that tractography results vary greatly, even when the subject and the total acquisition time are held constant. Further, we found that focusing on either spatial resolution or diffusion sampling at the expense of the other is counterproductive. A balanced consideration of both sampling domains produces the most anatomically accurate and consistent results. Copyright © 2014 Wiley Periodicals, Inc.

  16. Fast approach to evaluate MAP reconstruction for lesion detection and localization

    International Nuclear Information System (INIS)

    Qi, Jinyi; Huesman, Ronald H.

    2004-01-01

    Lesion detection is an important task in emission tomography. Localization ROC (LROC) studies are often used to analyze the lesion detection and localization performance. Most researchers rely on Monte Carlo reconstruction samples to obtain LROC curves, which can be very time-consuming for iterative algorithms. In this paper we develop a fast approach to obtain LROC curves that does not require Monte Carlo reconstructions. We use a channelized Hotelling observer model to search for lesions, and the results can be easily extended to other numerical observers. We theoretically analyzed the mean and covariance of the observer output. Assuming the observer outputs are multivariate Gaussian random variables, an LROC curve can be directly generated by integrating the conditional probability density functions. The high-dimensional integrals are calculated using a Monte Carlo method. The proposed approach is very fast because no iterative reconstruction is involved. Computer simulations show that the results of the proposed method match well with those obtained using the tradition LROC analysis

  17. Application of the entropy generation minimization method to a solar heat exchanger: A pseudo-optimization design process based on the analysis of the local entropy generation maps

    International Nuclear Information System (INIS)

    Giangaspero, Giorgio; Sciubba, Enrico

    2013-01-01

    This paper presents an application of the entropy generation minimization method to the pseudo-optimization of the configuration of the heat exchange surfaces in a Solar Rooftile. An initial “standard” commercial configuration is gradually improved by introducing design changes aimed at the reduction of the thermodynamic losses due to heat transfer and fluid friction. Different geometries (pins, fins and others) are analysed with a commercial CFD (Computational Fluid Dynamics) code that also computes the local entropy generation rate. The design improvement process is carried out on the basis of a careful analysis of the local entropy generation maps and the rationale behind each step of the process is discussed in this perspective. The results are compared with other entropy generation minimization techniques available in the recent technical literature. It is found that the geometry with pin-fins has the best performance among the tested ones, and that the optimal pin array shape parameters (pitch and span) can be determined by a critical analysis of the integrated and local entropy maps and of the temperature contours. - Highlights: ► An entropy generation minimization method is applied to a solar heat exchanger. ► The approach is heuristic and leads to a pseudo-optimization process with CFD as main tool. ► The process is based on the evaluation of the local entropy generation maps. ► The geometry with pin-fins in general outperforms all other configurations. ► The entropy maps and temperature contours can be used to determine the optimal pin array design parameters

  18. a Performance Comparison of Feature Detectors for Planetary Rover Mapping and Localization

    Science.gov (United States)

    Wan, W.; Peng, M.; Xing, Y.; Wang, Y.; Liu, Z.; Di, K.; Teng, B.; Mao, X.; Zhao, Q.; Xin, X.; Jia, M.

    2017-07-01

    Feature detection and matching are key techniques in computer vision and robotics, and have been successfully implemented in many fields. So far there is no performance comparison of feature detectors and matching methods for planetary mapping and rover localization using rover stereo images. In this research, we present a comprehensive evaluation and comparison of six feature detectors, including Moravec, Förstner, Harris, FAST, SIFT and SURF, aiming for optimal implementation of feature-based matching in planetary surface environment. To facilitate quantitative analysis, a series of evaluation criteria, including distribution evenness of matched points, coverage of detected points, and feature matching accuracy, are developed in the research. In order to perform exhaustive evaluation, stereo images, simulated under different baseline, pitch angle, and interval of adjacent rover locations, are taken as experimental data source. The comparison results show that SIFT offers the best overall performance, especially it is less sensitive to changes of image taken at adjacent locations.

  19. A PERFORMANCE COMPARISON OF FEATURE DETECTORS FOR PLANETARY ROVER MAPPING AND LOCALIZATION

    Directory of Open Access Journals (Sweden)

    W. Wan

    2017-07-01

    Full Text Available Feature detection and matching are key techniques in computer vision and robotics, and have been successfully implemented in many fields. So far there is no performance comparison of feature detectors and matching methods for planetary mapping and rover localization using rover stereo images. In this research, we present a comprehensive evaluation and comparison of six feature detectors, including Moravec, Förstner, Harris, FAST, SIFT and SURF, aiming for optimal implementation of feature-based matching in planetary surface environment. To facilitate quantitative analysis, a series of evaluation criteria, including distribution evenness of matched points, coverage of detected points, and feature matching accuracy, are developed in the research. In order to perform exhaustive evaluation, stereo images, simulated under different baseline, pitch angle, and interval of adjacent rover locations, are taken as experimental data source. The comparison results show that SIFT offers the best overall performance, especially it is less sensitive to changes of image taken at adjacent locations.

  20. Semantic Modeling for SNPs Associated with Ethnic Disparities in HapMap Samples

    Directory of Open Access Journals (Sweden)

    HyoYoung Kim

    2014-03-01

    Full Text Available Single-nucleotide polymorphisms (SNPs have been emerging out of the efforts to research human diseases and ethnic disparities. A semantic network is needed for in-depth understanding of the impacts of SNPs, because phenotypes are modulated by complex networks, including biochemical and physiological pathways. We identified ethnicity-specific SNPs by eliminating overlapped SNPs from HapMap samples, and the ethnicity-specific SNPs were mapped to the UCSC RefGene lists. Ethnicity-specific genes were identified as follows: 22 genes in the USA (CEU individuals, 25 genes in the Japanese (JPT individuals, and 332 genes in the African (YRI individuals. To analyze the biologically functional implications for ethnicity-specific SNPs, we focused on constructing a semantic network model. Entities for the network represented by "Gene," "Pathway," "Disease," "Chemical," "Drug," "ClinicalTrials," "SNP," and relationships between entity-entity were obtained through curation. Our semantic modeling for ethnicity-specific SNPs showed interesting results in the three categories, including three diseases ("AIDS-associated nephropathy," "Hypertension," and "Pelvic infection", one drug ("Methylphenidate", and five pathways ("Hemostasis," "Systemic lupus erythematosus," "Prostate cancer," "Hepatitis C virus," and "Rheumatoid arthritis". We found ethnicity-specific genes using the semantic modeling, and the majority of our findings was consistent with the previous studies - that an understanding of genetic variability explained ethnicity-specific disparities.

  1. Mapping diffuse interstellar bands in the local ISM on small scales via MUSE 3D spectroscopy. A pilot study based on globular cluster NGC 6397

    Science.gov (United States)

    Wendt, Martin; Husser, Tim-Oliver; Kamann, Sebastian; Monreal-Ibero, Ana; Richter, Philipp; Brinchmann, Jarle; Dreizler, Stefan; Weilbacher, Peter M.; Wisotzki, Lutz

    2017-11-01

    Context. We map the interstellar medium (ISM) including the diffuse interstellar bands (DIBs) in absorption toward the globular cluster NGC 6397 using VLT/MUSE. Assuming the absorbers are located at the rim of the Local Bubble we trace structures on the order of mpc (milliparsec, a few thousand AU). Aims: We aimed to demonstrate the feasibility to map variations of DIBs on small scales with MUSE. The sightlines defined by binned stellar spectra are separated by only a few arcseconds and we probe the absorption within a physically connected region. Methods: This analysis utilized the fitting residuals of individual stellar spectra of NGC 6397 member stars and analyzed lines from neutral species and several DIBs in Voronoi-binned composite spectra with high signal-to-noise ratio (S/N). Results: This pilot study demonstrates the power of MUSE for mapping the local ISM on very small scales which provides a new window for ISM observations. We detect small scale variations in Na I and K I as well as in several DIBs within few arcseconds, or mpc with regard to the Local Bubble. We verify the suitability of the MUSE 3D spectrograph for such measurements and gain new insights by probing a single physical absorber with multiple sight lines.

  2. APFiLoc: An Infrastructure-Free Indoor Localization Method Fusing Smartphone Inertial Sensors, Landmarks and Map Information

    Science.gov (United States)

    Shang, Jianga; Gu, Fuqiang; Hu, Xuke; Kealy, Allison

    2015-01-01

    The utility and adoption of indoor localization applications have been limited due to the complex nature of the physical environment combined with an increasing requirement for more robust localization performance. Existing solutions to this problem are either too expensive or too dependent on infrastructure such as Wi-Fi access points. To address this problem, we propose APFiLoc—a low cost, smartphone-based framework for indoor localization. The key idea behind this framework is to obtain landmarks within the environment and to use the augmented particle filter to fuse them with measurements from smartphone sensors and map information. A clustering method based on distance constraints is developed to detect organic landmarks in an unsupervised way, and the least square support vector machine is used to classify seed landmarks. A series of real-world experiments were conducted in complex environments including multiple floors and the results show APFiLoc can achieve 80% accuracy (phone in the hand) and around 70% accuracy (phone in the pocket) of the error less than 2 m error without the assistance of infrastructure like Wi-Fi access points. PMID:26516858

  3. Three-dimensional mapping of local cerebral perfusion in alcoholic encephalopathy with and without Wernicke-Korsakoff syndrome

    International Nuclear Information System (INIS)

    Hata, T.; Meyer, J.S.; Tanahashi, N.

    1987-01-01

    Seventeen severe chronic alcoholic patients with and without Wernicke-Korsakoff syndrome (WKS) were examined prospectively after being treated by withdrawal from alcohol. The WKS patients also received thiamine supplements. Three-dimensional measurements of local cerebral blood flow (LCBF) and local partition coefficients (L lambda) were made utilizing xenon contrast computed tomography (Xe CT-CBF). Results were displayed as color-coded brain maps before and after treatment and these were correlated with neurological and cognitive examinations. Before treatment chronic alcoholics without WKS (n = 10) showed diffuse reductions of LCBF values throughout all gray matter including hypothalamus, vicinity of nucleus basalis of Meynert, thalamus, and basal ganglia. Similar, but more severe, reductions were seen in patients with WKS (n = 7), however, white matter perfusion was also reduced. In WKS, most prominent reductions of LCBF were also seen in hypothalamus and basal forebrain nuclei but thalamus, basal ganglia, and limbic systems were severely reduced. After treatment, both groups with alcoholic encephalopathy showed marked clinical improvement and cerebral perfusion was restored toward normal. Chronic alcohol abuse, in the absence of thiamine deficiency, reduces CBF by direct neurotoxic effects. If thiamine deficiency is also present, more severe and localized hemodynamic reductions are superimposed

  4. New Map Symbol System for Disaster Management

    Science.gov (United States)

    Marinova, Silvia T.

    2018-05-01

    In the last 10 years Bulgaria was frequently affected by natural and man-made disasters that caused considerable losses. According to the Bulgarian Disaster Management Act (2006) disaster management should be planned at local, regional and national level. Disaster protection is based on plans that include maps such as hazard maps, maps for protection, maps for evacuation planning, etc. Decision-making and cooperation between two or more neighboring municipalities or regions in crisis situation are still rendered difficult because the maps included in the plans differ in scale, colors, map symbols and cartographic design. To improve decision-making process in case of emergency and to reduce the number of human loss and property damages disaster management plans at local and regional level should be supported by detailed thematic maps created in accordance with uniform contents, map symbol system and design. The paper proposes a new symbol system for disaster management that includes a four level hierarchical classification of objects and phenomena according to their type and origin. All objects and phenomena of this classification are divided into five categories: disasters; infrastructure; protection services and infrastructure for protection; affected people and affected infrastructure; operational sites and activities. The symbols of these categories are shown with different background colors and shapes so that they are identifiable. All the symbols have simple but associative design. The new symbol system is used in the design of a series of maps for disaster management at local and regional level.

  5. Adjusting for sampling variability in sparse data: geostatistical approaches to disease mapping.

    Science.gov (United States)

    Hampton, Kristen H; Serre, Marc L; Gesink, Dionne C; Pilcher, Christopher D; Miller, William C

    2011-10-06

    Disease maps of crude rates from routinely collected health data indexed at a small geographical resolution pose specific statistical problems due to the sparse nature of the data. Spatial smoothers allow areas to borrow strength from neighboring regions to produce a more stable estimate of the areal value. Geostatistical smoothers are able to quantify the uncertainty in smoothed rate estimates without a high computational burden. In this paper, we introduce a uniform model extension of Bayesian Maximum Entropy (UMBME) and compare its performance to that of Poisson kriging in measures of smoothing strength and estimation accuracy as applied to simulated data and the real data example of HIV infection in North Carolina. The aim is to produce more reliable maps of disease rates in small areas to improve identification of spatial trends at the local level. In all data environments, Poisson kriging exhibited greater smoothing strength than UMBME. With the simulated data where the true latent rate of infection was known, Poisson kriging resulted in greater estimation accuracy with data that displayed low spatial autocorrelation, while UMBME provided more accurate estimators with data that displayed higher spatial autocorrelation. With the HIV data, UMBME performed slightly better than Poisson kriging in cross-validatory predictive checks, with both models performing better than the observed data model with no smoothing. Smoothing methods have different advantages depending upon both internal model assumptions that affect smoothing strength and external data environments, such as spatial correlation of the observed data. Further model comparisons in different data environments are required to provide public health practitioners with guidelines needed in choosing the most appropriate smoothing method for their particular health dataset.

  6. X-ray fluorescence microscopy artefacts in elemental maps of topologically complex samples: Analytical observations, simulation and a map correction method

    Science.gov (United States)

    Billè, Fulvio; Kourousias, George; Luchinat, Enrico; Kiskinova, Maya; Gianoncelli, Alessandra

    2016-08-01

    XRF spectroscopy is among the most widely used non-destructive techniques for elemental analysis. Despite the known angular dependence of X-ray fluorescence (XRF), topological artefacts remain an unresolved issue when using X-ray micro- or nano-probes. In this work we investigate the origin of the artefacts in XRF imaging of topologically complex samples, which are unresolved problems in studies of organic matter due to the limited travel distances of low energy XRF emission from the light elements. In particular we mapped Human Embryonic Kidney (HEK293T) cells. The exemplary results with biological samples, obtained with a soft X-ray scanning microscope installed at a synchrotron facility were used for testing a mathematical model based on detector response simulations, and for proposing an artefact correction method based on directional derivatives. Despite the peculiar and specific application, the methodology can be easily extended to hard X-rays and to set-ups with multi-array detector systems when the dimensions of surface reliefs are in the order of the probing beam size.

  7. Map based localization to assist commercial fleet operations.

    Science.gov (United States)

    2014-08-01

    This report outlines key recent contributions to the state of the art in lane detection, lane departure warning, : and map-based sensor fusion algorithms. These key studies are used as a basis for a discussion about the : limitations of systems that ...

  8. Local ancestry transitions modify snp-trait associations.

    Science.gov (United States)

    Fish, Alexandra E; Crawford, Dana C; Capra, John A; Bush, William S

    2018-01-01

    Genomic maps of local ancestry identify ancestry transitions - points on a chromosome where recent recombination events in admixed individuals have joined two different ancestral haplotypes. These events bring together alleles that evolved within separate continential populations, providing a unique opportunity to evaluate the joint effect of these alleles on health outcomes. In this work, we evaluate the impact of genetic variants in the context of nearby local ancestry transitions within a sample of nearly 10,000 adults of African ancestry with traits derived from electronic health records. Genetic data was located using the Metabochip, and used to derive local ancestry. We develop a model that captures the effect of both single variants and local ancestry, and use it to identify examples where local ancestry transitions significantly interact with nearby variants to influence metabolic traits. In our most compelling example, we find that the minor allele of rs16890640 occuring on a European background with a downstream local ancestry transition to African ancestry results in significantly lower mean corpuscular hemoglobin and volume. This finding represents a new way of discovering genetic interactions, and is supported by molecular data that suggest changes to local ancestry may impact local chromatin looping.

  9. Optimization of the sampling scheme for maps of physical and chemical properties estimated by kriging

    Directory of Open Access Journals (Sweden)

    Gener Tadeu Pereira

    2013-10-01

    Full Text Available The sampling scheme is essential in the investigation of the spatial variability of soil properties in Soil Science studies. The high costs of sampling schemes optimized with additional sampling points for each physical and chemical soil property, prevent their use in precision agriculture. The purpose of this study was to obtain an optimal sampling scheme for physical and chemical property sets and investigate its effect on the quality of soil sampling. Soil was sampled on a 42-ha area, with 206 geo-referenced points arranged in a regular grid spaced 50 m from each other, in a depth range of 0.00-0.20 m. In order to obtain an optimal sampling scheme for every physical and chemical property, a sample grid, a medium-scale variogram and the extended Spatial Simulated Annealing (SSA method were used to minimize kriging variance. The optimization procedure was validated by constructing maps of relative improvement comparing the sample configuration before and after the process. A greater concentration of recommended points in specific areas (NW-SE direction was observed, which also reflects a greater estimate variance at these locations. The addition of optimal samples, for specific regions, increased the accuracy up to 2 % for chemical and 1 % for physical properties. The use of a sample grid and medium-scale variogram, as previous information for the conception of additional sampling schemes, was very promising to determine the locations of these additional points for all physical and chemical soil properties, enhancing the accuracy of kriging estimates of the physical-chemical properties.

  10. Exponential local discriminant embedding and its application to face recognition.

    Science.gov (United States)

    Dornaika, Fadi; Bosaghzadeh, Alireza

    2013-06-01

    Local discriminant embedding (LDE) has been recently proposed to overcome some limitations of the global linear discriminant analysis method. In the case of a small training data set, however, LDE cannot directly be applied to high-dimensional data. This case is the so-called small-sample-size (SSS) problem. The classical solution to this problem was applying dimensionality reduction on the raw data (e.g., using principal component analysis). In this paper, we introduce a novel discriminant technique called "exponential LDE" (ELDE). The proposed ELDE can be seen as an extension of LDE framework in two directions. First, the proposed framework overcomes the SSS problem without discarding the discriminant information that was contained in the null space of the locality preserving scatter matrices associated with LDE. Second, the proposed ELDE is equivalent to transforming original data into a new space by distance diffusion mapping (similar to kernel-based nonlinear mapping), and then, LDE is applied in such a new space. As a result of diffusion mapping, the margin between samples belonging to different classes is enlarged, which is helpful in improving classification accuracy. The experiments are conducted on five public face databases: Yale, Extended Yale, PF01, Pose, Illumination, and Expression (PIE), and Facial Recognition Technology (FERET). The results show that the performances of the proposed ELDE are better than those of LDE and many state-of-the-art discriminant analysis techniques.

  11. Fault Localization Method by Partitioning Memory Using Memory Map and the Stack for Automotive ECU Software Testing

    Directory of Open Access Journals (Sweden)

    Kwanhyo Kim

    2016-09-01

    Full Text Available Recently, the usage of the automotive Electronic Control Unit (ECU and its software in cars is increasing. Therefore, as the functional complexity of such software increases, so does the likelihood of software-related faults. Therefore, it is important to ensure the reliability of ECU software in order to ensure automobile safety. For this reason, systematic testing methods are required that can guarantee software quality. However, it is difficult to locate a fault during testing with the current ECU development system because a tester performs the black-box testing using a Hardware-in-the-Loop (HiL simulator. Consequently, developers consume a large amount of money and time for debugging because they perform debugging without any information about the location of the fault. In this paper, we propose a method for localizing the fault utilizing memory information during black-box testing. This is likely to be of use to developers who debug automotive software. In order to observe whether symbols stored in the memory have been updated, the memory is partitioned by a memory map and the stack, thus the fault candidate region is reduced. A memory map method has the advantage of being able to finely partition the memory, and the stack method can partition the memory without a memory map. We validated these methods by applying these to HiL testing of the ECU for a body control system. The preliminary results indicate that a memory map and the stack reduce the possible fault locations to 22% and 19% of the updated memory, respectively.

  12. Mapping the backbone of science.

    Energy Technology Data Exchange (ETDEWEB)

    Klavans, Richard (Indiana University, Bloomington, IN); BÞorner, Katy (Strategies for Science & Technology, Incorporation, Berwyn, PA); Boyack, Kevin W.

    2004-11-01

    This paper presents a new map representing the structure of all of science, based on journal articles, including both the natural and social sciences. Similar to cartographic maps of our world, the map of science provides a bird's eye view of today's scientific landscape. It can be used to visually identify major areas of science, their size, similarity, and interconnectedness. In order to be useful, the map needs to be accurate on a local and on a global scale. While our recent work has focused on the former aspect, this paper summarizes results on how to achieve structural accuracy. Eight alternative measures of journal similarity were applied to a data set of 7,121 journals covering over 1 million documents in the combined Science Citation and Social Science Citation Indexes. For each journal similarity measure we generated two-dimensional spatial layouts using the force-directed graph layout tool, VxOrd. Next, mutual information values were calculated for each graph at different clustering levels to give a measure of structural accuracy for each map. The best co-citation and inter-citation maps according to local and structural accuracy were selected and are presented and characterized. These two maps are compared to establish robustness. The inter-citation map is then used to examine linkages between disciplines. Biochemistry appears as the most interdisciplinary discipline in science.

  13. The effect of local heat on term neonates pain intensity during heel-blood sampling

    Directory of Open Access Journals (Sweden)

    R. GHobadi Mohebi

    2017-04-01

    Full Text Available Aims: Newborns are more sensitive to pain than adults and are more susceptible to the long-term complications of pain. So, it is necessary to use procedures for reducing pain in newborns. The aim of this study was to determine the effect of local heat on the pain intensity of heel-blood sampling in the term newborns. Material & Methods: In this randomized controlled clinical trial study, in 2012, 63 healthy 3 to 5-day newborns who were referred to Shahid Delkhah Health Center in Ferdows were selected by random sampling method and randomly divided into 3 groups (21 people in each group: test (heat, placebo (sound and control. The pain intensity of newborns before, during and after heel-blood sampling was evaluated. The data collection tools were demographic questionnaire and Neonatal Infant Pain Scale (NIPS. Data were analyzed by SPSS 14.5 software and chi-square test, one-way ANOVA, Tukey's post hoc test, and ANOVA with repeated observations. Finding: The mean pain intensity in the three groups was not significantly different before intervention (p=0.86, but the mean pain intensity was lower in the test group than in the other two groups (p=0.006. After heel-blood sampling, the mean pain intensity was the least in the test group and was the most in the control group (p<0.001. Conclusion: Local heat during and after heel blood sampling decreases pain intensity in the term newborns.

  14. Empirical evaluation of a practical indoor mobile robot navigation method using hybrid maps

    DEFF Research Database (Denmark)

    Özkil, Ali Gürcan; Fan, Zhun; Xiao, Jizhong

    2010-01-01

    This video presents a practical navigation scheme for indoor mobile robots using hybrid maps. The method makes use of metric maps for local navigation and a topological map for global path planning. Metric maps are generated as occupancy grids by a laser range finder to represent local information...... about partial areas. The global topological map is used to indicate the connectivity of the ‘places-of-interests’ in the environment and the interconnectivity of the local maps. Visual tags on the ceiling to be detected by the robot provide valuable information and contribute to reliable localization...... that the method is implemented successfully on physical robot in a hospital environment, which provides a practical solution for indoor navigation....

  15. Characterization of rock samples localized in some sites of the Mexican Pacific coast

    International Nuclear Information System (INIS)

    Pena, P.; Torre, J. de la; Falcon, T.; Segovia, N.; Azorin, J.

    1999-01-01

    Geophysical studies in zones of high seismicity have showed differences in the content of radioactive material that is used in the study of the geochemical behavior of the subsoil. In an emanometric mapping of radon in soil realized in the Mexican Pacific coast were finding distinct levels in zones with different lithology. With the finality to know the mineralization types in two zones of study which are localized in the Guerrero coast and they belonging to terrains named Guerrero and Xolapa it was determined the mineralogic characteristics in two types of rocks. The identification of the rocks was realized by X-ray diffraction and was determined the elemental chemical composition using a scanning electron microscope. It was indicated in the results obtained that in the two types of rocks were found minerals such as: quartz, albite, microcline anortite, ferroactinolite and biotite. However, it was found differences between them by the presence of their mineralogic compounds because in the rock belonging to Xolapa terrain were presented whereas in the rock localized in the Guerrero terrain were presented sodic and potassic feldspars. The analysis by the Elemental Chemical Composition technique (Energy Dispersive Spectroscopy) corroborated the results obtained by the X-ray diffraction technique. (Author)

  16. Application of self-organising maps towards segmentation of soybean samples by determination of inorganic compounds content.

    Science.gov (United States)

    Cremasco, Hágata; Borsato, Dionísio; Angilelli, Karina Gomes; Galão, Olívio Fernandes; Bona, Evandro; Valle, Marcos Eduardo

    2016-01-15

    In this study, 20 samples of soybean, both transgenic and conventional cultivars, which were planted in two different regions, Londrina and Ponta Grossa, both located at Paraná, Brazil, were analysed. In order to verify whether the inorganic compound levels in soybeans varied with the region of planting, K, P, Ca, Mg, S, Zn, Mn, Fe, Cu and B contents were analysed by an artificial neural network self-organising map. It was observed that with a topology 10 × 10, 8000 epochs, initial learning rate of 0.1 and initial neighbourhood ratio of 4.5, the network was able to differentiate samples according to region of origin. Among all of the variables analysed by the artificial neural network, the elements Zn, Ca and Mn were those which most contributed to the classification of the samples. The results indicated that samples planted in these two regions differ in their mineral content; however, conventional and transgenic samples grown in the same region show no difference in mineral contents in the grain. © 2015 Society of Chemical Industry.

  17. THE ALFALFA H α SURVEY. I. PROJECT DESCRIPTION AND THE LOCAL STAR FORMATION RATE DENSITY FROM THE FALL SAMPLE

    International Nuclear Information System (INIS)

    Sistine, Angela Van; Salzer, John J.; Janowiecki, Steven; Sugden, Arthur; Giovanelli, Riccardo; Haynes, Martha P.; Jaskot, Anne E.; Wilcots, Eric M.

    2016-01-01

    The ALFALFA H α survey utilizes a large sample of H i-selected galaxies from the ALFALFA survey to study star formation (SF) in the local universe. ALFALFA H α contains 1555 galaxies with distances between ∼20 and ∼100 Mpc. We have obtained continuum-subtracted narrowband H α images and broadband R images for each galaxy, creating one of the largest homogeneous sets of H α images ever assembled. Our procedures were designed to minimize the uncertainties related to the calculation of the local SF rate density (SFRD). The galaxy sample we constructed is as close to volume-limited as possible, is a robust statistical sample, and spans a wide range of galaxy environments. In this paper, we discuss the properties of our Fall sample of 565 galaxies, our procedure for deriving individual galaxy SF rates, and our method for calculating the local SFRD. We present a preliminary value of log(SFRD[ M ⊙ yr −1 Mpc −3 ]) = −1.747 ± 0.018 (random) ±0.05 (systematic) based on the 565 galaxies in our Fall sub-sample. Compared to the weighted average of SFRD values around z ≈ 2, our local value indicates a drop in the global SFRD of a factor of 10.2 over that lookback time.

  18. Passive Acoustic Source Localization at a Low Sampling Rate Based on a Five-Element Cross Microphone Array

    Directory of Open Access Journals (Sweden)

    Yue Kan

    2015-06-01

    Full Text Available Accurate acoustic source localization at a low sampling rate (less than 10 kHz is still a challenging problem for small portable systems, especially for a multitasking micro-embedded system. A modification of the generalized cross-correlation (GCC method with the up-sampling (US theory is proposed and defined as the US-GCC method, which can improve the accuracy of the time delay of arrival (TDOA and source location at a low sampling rate. In this work, through the US operation, an input signal with a certain sampling rate can be converted into another signal with a higher frequency. Furthermore, the optimal interpolation factor for the US operation is derived according to localization computation time and the standard deviation (SD of target location estimations. On the one hand, simulation results show that absolute errors of the source locations based on the US-GCC method with an interpolation factor of 15 are approximately from 1/15- to 1/12-times those based on the GCC method, when the initial same sampling rates of both methods are 8 kHz. On the other hand, a simple and small portable passive acoustic source localization platform composed of a five-element cross microphone array has been designed and set up in this paper. The experiments on the established platform, which accurately locates a three-dimensional (3D near-field target at a low sampling rate demonstrate that the proposed method is workable.

  19. Deterministic Diffusion in Delayed Coupled Maps

    International Nuclear Information System (INIS)

    Sozanski, M.

    2005-01-01

    Coupled Map Lattices (CML) are discrete time and discrete space dynamical systems used for modeling phenomena arising in nonlinear systems with many degrees of freedom. In this work, the dynamical and statistical properties of a modified version of the CML with global coupling are considered. The main modification of the model is the extension of the coupling over a set of local map states corresponding to different time iterations. The model with both stochastic and chaotic one-dimensional local maps is studied. Deterministic diffusion in the CML under variation of a control parameter is analyzed for unimodal maps. As a main result, simple relations between statistical and dynamical measures are found for the model and the cases where substituting nonlinear lattices with simpler processes is possible are presented. (author)

  20. Mapping in vitro local material properties of intact and disrupted virions at high resolution using multi-harmonic atomic force microscopy.

    Science.gov (United States)

    Cartagena, Alexander; Hernando-Pérez, Mercedes; Carrascosa, José L; de Pablo, Pedro J; Raman, Arvind

    2013-06-07

    Understanding the relationships between viral material properties (stiffness, strength, charge density, adhesion, hydration, viscosity, etc.), structure (protein sub-units, genome, surface receptors, appendages), and functions (self-assembly, stability, disassembly, infection) is of significant importance in physical virology and nanomedicine. Conventional Atomic Force Microscopy (AFM) methods have measured a single physical property such as the stiffness of the entire virus from nano-indentation at a few points which severely limits the study of structure-property-function relationships. We present an in vitro dynamic AFM technique operating in the intermittent contact regime which synthesizes anharmonic Lorentz-force excited AFM cantilevers to map quantitatively at nanometer resolution the local electro-mechanical force gradient, adhesion, and hydration layer viscosity within individual φ29 virions. Furthermore, the changes in material properties over the entire φ29 virion provoked by the local disruption of its shell are studied, providing evidence of bacteriophage depressurization. The technique significantly generalizes recent multi-harmonic theory (A. Raman, et al., Nat. Nanotechnol., 2011, 6, 809-814) and enables high-resolution in vitro quantitative mapping of multiple material properties within weakly bonded viruses and nanoparticles with complex structure that otherwise cannot be observed using standard AFM techniques.

  1. Diagnostic usefulness of endorectal magnetic resonance imaging with dynamic contrast-enhancement in patients with localized prostate cancer. Mapping studies with biopsy specimens

    International Nuclear Information System (INIS)

    Tanaka, Nobumichi; Samma, Shoji; Joko, Masanori; Akiyama, Tatsuya; Takewa, Megumi; Kitano, Satoru; Okajima, Eigoro

    1999-01-01

    New diagnostic criteria for dynamic magnetic resonance (MR) imaging in prostate cancer are presented. The diagnostic usefulness of endorectal MR imaging with dynamic contrast-enhancement in localized prostate cancer and the validity of these criteria were evaluated. Eighteen untreated patients who were suspected of localized prostate cancer were included in the study. They received endorectal dynamic MR imaging before systematic sextant needle biopsy. First, a mapping study with the findings of MR images and histopathology of biopsy specimens was performed in eight patients out of 18 to compare the difference in T2-weighted images with the endorectal coil and the body coil in the same individuals. Second, another mapping study was performed in all 18 patients by analyzing the findings of endorectal dynamic MR images. For the diagnosis of prostate cancer in MR imaging, we offered diagnostic criteria from our experience in addition to those in plain T2-weighted images from the literature. The overall diagnostic rates of endorectal dynamic MR imaging were 88.9% in accuracy, 100% in sensitivity, and 81.8% in specificity. In the comparison of the endorectal and body coils in T2-weighted images in eight patients, there was no difference in the diagnostic rates except for one more histopathologic false positive portion in endorectal MR imaging. In the second mapping study in 18 patients, the diagnostic rates were 92.6% in accuracy, 88.9% in sensitivity and 93.3% in specificity. Endorectal dynamic imaging raised the diagnostic sensitivity from 77.8 to 88.9%. The data demonstrated the validity of this diagnostic criteria and the diagnostic usefulness of endorectal dynamic MR imaging in localized prostate cancer. (author)

  2. Estimation of Initial Position Using Line Segment Matching in Maps

    Directory of Open Access Journals (Sweden)

    Chongyang Wei

    2016-06-01

    Full Text Available While navigating in a typical traffic scene, with a drastic drift or sudden jump in its Global Positioning System (GPS position, the localization based on such an initial position is unable to extract precise overlapping data from the prior map in order to match the current data, thus rendering the localization as unfeasible. In this paper, we first propose a new method to estimate an initial position by matching the infrared reflectivity maps. The maps consist of a highly precise prior map, built with the offline simultaneous localization and mapping (SLAM technique, and a smooth current map, built with the integral over velocities. Considering the attributes of the maps, we first propose to exploit the stable, rich line segments to match the lidar maps. To evaluate the consistency of the candidate line pairs in both maps, we propose to adopt the local appearance, pairwise geometric attribute and structural likelihood to construct an affinity graph, as well as employ a spectral algorithm to solve the graph efficiently. The initial position is obtained according to the relationship between the vehicle's current position and matched lines. Experiments on the campus with a GPS error of dozens of metres show that our algorithm can provide an accurate initial value with average longitudinal and lateral errors being 1.68m and 1.04m, respectively.

  3. Dependence of critical current on sample length analyzed by the variation of local critical current bent of BSCCO superconducting composite tape

    International Nuclear Information System (INIS)

    Matsubayashi, H.; Mukai, Y.; Shin, J.K.; Ochiai, S.; Okuda, H.; Osamura, K.; Otto, A.; Malozemoff, A.

    2008-01-01

    Using the high critical current type BSCCO composite tape fabricated at American Superconductor Corporation, the relation of overall critical current to the distribution of local critical current and the dependence of overall critical current on sample length of the bent samples were studied experimentally and analytically. The measured overall critical current was described well from the distribution of local critical current and n-value of the constituting short elements, by regarding the overall sample to be composed of local series circuits and applying the voltage summation model. Also the dependence of overall critical current on sample length could be reproduced in computer satisfactorily by the proposed simulation method

  4. Mapping local cerebral blood flow by means of computerized tomography with a short inhalation of low-dose stable xenon

    International Nuclear Information System (INIS)

    Nakagawara, Jyoji; Karasawa, Jun; Tasawa, Toshiaki; Touho, Hajime; Nakauchi, Mikio; Kagawa, Masa-aki; Asai, Masa-aki; Kuriyama, Yoshihiro; Kikuchi, Haruhiko.

    1986-01-01

    A non-invasive technique has been developed for mapping the local blood-brain partition coefficient (λi), the local build-up rate constant (κi), and the local cerebral blood flow (l-CBF) by means of xenon-enhanced computerized tomography (CT) using a YMS CT 9000 scanner. After denitrogenation for 10 minutes, a 30 % xenon/oxygen mixture is inhaled for 4 - 8 minutes through a rubber face-mask and a delivery system of stable xenon. The time course of local cerebral CT enhancement is utilized in order to calculate, the λi, κi, and l-CBF values. The CT enhancement data during the washin-washout phase are fitted to the mathematical functions, based on Kety's formula, using least-squares curve-fitting analysis. Several case studies of patients with cerebral vascular accidents are presented to demonstrate the characterization of the λi and l-CBF patterns in various tissues; the results are of sufficient quality for the management of patients. The theoretical assumptions underlying stable xenon CT CBF measurements are discussed. (author)

  5. Distributed Monocular SLAM for Indoor Map Building

    Directory of Open Access Journals (Sweden)

    Ruwan Egodagamage

    2017-01-01

    Full Text Available Utilization and generation of indoor maps are critical elements in accurate indoor tracking. Simultaneous Localization and Mapping (SLAM is one of the main techniques for such map generation. In SLAM an agent generates a map of an unknown environment while estimating its location in it. Ubiquitous cameras lead to monocular visual SLAM, where a camera is the only sensing device for the SLAM process. In modern applications, multiple mobile agents may be involved in the generation of such maps, thus requiring a distributed computational framework. Each agent can generate its own local map, which can then be combined into a map covering a larger area. By doing so, they can cover a given environment faster than a single agent. Furthermore, they can interact with each other in the same environment, making this framework more practical, especially for collaborative applications such as augmented reality. One of the main challenges of distributed SLAM is identifying overlapping maps, especially when relative starting positions of agents are unknown. In this paper, we are proposing a system having multiple monocular agents, with unknown relative starting positions, which generates a semidense global map of the environment.

  6. A Fast Map Merging Algorithm in the Field of Multirobot SLAM

    Directory of Open Access Journals (Sweden)

    Yanli Liu

    2013-01-01

    Full Text Available In recent years, the research on single-robot simultaneous localization and mapping (SLAM has made a great success. However, multirobot SLAM faces many challenging problems, including unknown robot poses, unshared map, and unstable communication. In this paper, a map merging algorithm based on virtual robot motion is proposed for multi-robot SLAM. The thinning algorithm is used to construct the skeleton of the grid map’s empty area, and a mobile robot is simulated in one map. The simulated data is used as information sources in the other map to do partial map Monte Carlo localization; if localization succeeds, the relative pose hypotheses between the two maps can be computed easily. We verify these hypotheses using the rendezvous technique and use them as initial values to optimize the estimation by a heuristic random search algorithm.

  7. Population weighted raster maps can communicate findings of social audits: examples from three continents

    Directory of Open Access Journals (Sweden)

    Mitchell Steven

    2011-12-01

    Full Text Available Abstract Background Maps can portray trends, patterns, and spatial differences that might be overlooked in tabular data and are now widely used in health research. Little has been reported about the process of using maps to communicate epidemiological findings. Method Population weighted raster maps show colour changes over the study area. Similar to the rasters of barometric pressure in a weather map, data are the health occurrence – a peak on the map represents a higher value of the indicator in question. The population relevance of each sentinel site, as determined in the stratified last stage random sample, combines with geography (inverse-distance weighting to provide a population-weighted extension of each colour. This transforms the map to show population space rather than simply geographic space. Results Maps allowed discussion of strategies to reduce violence against women in a context of political sensitivity about quoting summary indicator figures. Time-series maps showed planners how experiences of health services had deteriorated despite a reform programme; where in a country HIV risk behaviours were improving; and how knowledge of an economic development programme quickly fell off across a region. Change maps highlighted where indicators were improving and where they were deteriorating. Maps of potential impact of interventions, based on multivariate modelling, displayed how partial and full implementation of programmes could improve outcomes across a country. Scale depends on context. To support local planning, district maps or local government authority maps of health indicators were more useful than national maps; but multinational maps of outcomes were more useful for regional institutions. Mapping was useful to illustrate in which districts enrolment in religious schools – a rare occurrence - was more prevalent. Conclusions Population weighted raster maps can present social audit findings in an accessible and compelling

  8. Population weighted raster maps can communicate findings of social audits: examples from three continents.

    Science.gov (United States)

    Mitchell, Steven; Cockcroft, Anne; Andersson, Neil

    2011-12-21

    Maps can portray trends, patterns, and spatial differences that might be overlooked in tabular data and are now widely used in health research. Little has been reported about the process of using maps to communicate epidemiological findings. Population weighted raster maps show colour changes over the study area. Similar to the rasters of barometric pressure in a weather map, data are the health occurrence--a peak on the map represents a higher value of the indicator in question. The population relevance of each sentinel site, as determined in the stratified last stage random sample, combines with geography (inverse-distance weighting) to provide a population-weighted extension of each colour. This transforms the map to show population space rather than simply geographic space. Maps allowed discussion of strategies to reduce violence against women in a context of political sensitivity about quoting summary indicator figures. Time-series maps showed planners how experiences of health services had deteriorated despite a reform programme; where in a country HIV risk behaviours were improving; and how knowledge of an economic development programme quickly fell off across a region. Change maps highlighted where indicators were improving and where they were deteriorating. Maps of potential impact of interventions, based on multivariate modelling, displayed how partial and full implementation of programmes could improve outcomes across a country. Scale depends on context. To support local planning, district maps or local government authority maps of health indicators were more useful than national maps; but multinational maps of outcomes were more useful for regional institutions. Mapping was useful to illustrate in which districts enrolment in religious schools--a rare occurrence--was more prevalent. Population weighted raster maps can present social audit findings in an accessible and compelling way, increasing the use of evidence by planners with limited numeracy

  9. Adjusting for sampling variability in sparse data: geostatistical approaches to disease mapping

    Directory of Open Access Journals (Sweden)

    Pilcher Christopher D

    2011-10-01

    Full Text Available Abstract Background Disease maps of crude rates from routinely collected health data indexed at a small geographical resolution pose specific statistical problems due to the sparse nature of the data. Spatial smoothers allow areas to borrow strength from neighboring regions to produce a more stable estimate of the areal value. Geostatistical smoothers are able to quantify the uncertainty in smoothed rate estimates without a high computational burden. In this paper, we introduce a uniform model extension of Bayesian Maximum Entropy (UMBME and compare its performance to that of Poisson kriging in measures of smoothing strength and estimation accuracy as applied to simulated data and the real data example of HIV infection in North Carolina. The aim is to produce more reliable maps of disease rates in small areas to improve identification of spatial trends at the local level. Results In all data environments, Poisson kriging exhibited greater smoothing strength than UMBME. With the simulated data where the true latent rate of infection was known, Poisson kriging resulted in greater estimation accuracy with data that displayed low spatial autocorrelation, while UMBME provided more accurate estimators with data that displayed higher spatial autocorrelation. With the HIV data, UMBME performed slightly better than Poisson kriging in cross-validatory predictive checks, with both models performing better than the observed data model with no smoothing. Conclusions Smoothing methods have different advantages depending upon both internal model assumptions that affect smoothing strength and external data environments, such as spatial correlation of the observed data. Further model comparisons in different data environments are required to provide public health practitioners with guidelines needed in choosing the most appropriate smoothing method for their particular health dataset.

  10. Phenotypic and Genotypic Detection of Campylobacter jejuni at Local Chicken and Chicken Meat

    Directory of Open Access Journals (Sweden)

    A Rosyidi

    2010-05-01

    Full Text Available The Objective of this study was to identify the existence of Campylobacter jejuni based on phenotypic and genotypic characteristic in local chicken and chicken meats. Samples of local chicken intestine and meat were tested for the bacterial existence. Phenotypic examination was carried out by means of cultivation followed by gram staining and biochemical tests. Genotypic examination was conducted by polymerase chain reaction (PCR using genus specific16S rRNA gene at 816 bp and membrane-associated protein A (mapA gene at 589 bp as Campylobacter jejuni species-specific gene. The result of phenotypic detection revealed the existence of Campylobacter spp as gram negative, curved rod shape, oxidase positive, urease negative and motile. Genotypic examination also indicated the existence of bacteria using both primers. However, no Campylobacter jejuni detected from meat of the chickens. The results suggest that the method of PCR using a primer detecting species-specific gene of Campylobacter jejuni gives a rapid and accurate detection of the bacteria as compared to that using phenotypic and biochemical test. Identification of Campylobacter spp from chicken meats should be improved with enrichment method and sample collection. (Animal Production 12(2: 128-134 (2010Key Words: Campylobacter jejuni, mapA gene, local chicken

  11. Interfacial orientation and misorientation relationships in nanolamellar Cu/Nb composites using transmission-electron-microscope-based orientation and phase mapping

    International Nuclear Information System (INIS)

    Liu, X.; Nuhfer, N.T.; Rollett, A.D.; Sinha, S.; Lee, S.-B.; Carpenter, J.S.; LeDonne, J.E.; Darbal, A.; Barmak, K.

    2014-01-01

    A transmission-electron-microscope-based orientation mapping technique that makes use of beam precession to achieve near-kinematical conditions was used to map the phase and crystal orientations in nanolamellar Cu/Nb composites with average layer thicknesses of 86, 30 and 18 nm. Maps of high quality and reliability were obtained by comparing the recorded diffraction patterns with pre-calculated templates. Particular care was taken in optimizing the dewarping parameters and in calibrating the frames of reference. Layers with thicknesses as low as 4 nm were successfully mapped. Heterophase interface plane and character distributions (HIPD and HICD, respectively) of Cu and Nb phases from the samples were determined from the orientation maps. In addition, local orientation relation stereograms of the Cu/Nb interfaces were calculated, and these revealed the detailed layer-to-layer texture information. The results are in agreement with previously reported neutron-diffraction-based and precession-electron-diffraction-based measurements on an accumulated roll bonding (ARB)-fabricated Cu/Nb sample with an average layer thickness of 30 nm as well as scanning-electron-microscope-based electron backscattered diffraction HIPD/HICD plots of ARB-fabricated Cu/Nb samples with layer thicknesses between 200 and 600 nm

  12. Mapping species distributions with MAXENT using a geographically biased sample of presence data: a performance assessment of methods for correcting sampling bias.

    Science.gov (United States)

    Fourcade, Yoan; Engler, Jan O; Rödder, Dennis; Secondi, Jean

    2014-01-01

    MAXENT is now a common species distribution modeling (SDM) tool used by conservation practitioners for predicting the distribution of a species from a set of records and environmental predictors. However, datasets of species occurrence used to train the model are often biased in the geographical space because of unequal sampling effort across the study area. This bias may be a source of strong inaccuracy in the resulting model and could lead to incorrect predictions. Although a number of sampling bias correction methods have been proposed, there is no consensual guideline to account for it. We compared here the performance of five methods of bias correction on three datasets of species occurrence: one "virtual" derived from a land cover map, and two actual datasets for a turtle (Chrysemys picta) and a salamander (Plethodon cylindraceus). We subjected these datasets to four types of sampling biases corresponding to potential types of empirical biases. We applied five correction methods to the biased samples and compared the outputs of distribution models to unbiased datasets to assess the overall correction performance of each method. The results revealed that the ability of methods to correct the initial sampling bias varied greatly depending on bias type, bias intensity and species. However, the simple systematic sampling of records consistently ranked among the best performing across the range of conditions tested, whereas other methods performed more poorly in most cases. The strong effect of initial conditions on correction performance highlights the need for further research to develop a step-by-step guideline to account for sampling bias. However, this method seems to be the most efficient in correcting sampling bias and should be advised in most cases.

  13. Fate mapping of the silkworm, Bombyx mori, using localized UV irradiation of the egg at fertilization

    International Nuclear Information System (INIS)

    Myohara, Maroko

    1994-01-01

    Bombyx eggs at the fertilization stage (0-2 hours after oviposition) were irradiated with a scanning UV-laser microbeam (355 nm) over an area of about 1% of the total egg surface. In spite of absence of nuclei or cells at the irradiated sites, larvae from treated eggs showed localized cuticle defects in the integument. The location and frequency of the defects within the cuticular pattern correlated closely to the site of irradiation both in the anteroposterior and the dorsoventral direction. Based on the correlation, presumptive regions for each larval segment were located and a fate map of the Bombyx egg was established. (author)

  14. Active Neural Localization

    OpenAIRE

    Chaplot, Devendra Singh; Parisotto, Emilio; Salakhutdinov, Ruslan

    2018-01-01

    Localization is the problem of estimating the location of an autonomous agent from an observation and a map of the environment. Traditional methods of localization, which filter the belief based on the observations, are sub-optimal in the number of steps required, as they do not decide the actions taken by the agent. We propose "Active Neural Localizer", a fully differentiable neural network that learns to localize accurately and efficiently. The proposed model incorporates ideas of tradition...

  15. Map showing thermal-alteration indicies in roadless areas and the Santa Lucia Wilderness in the Los Padres National Forest, Southwestern California

    Science.gov (United States)

    Frederiksen, N.O.

    1985-01-01

    This map shows thermal-alteration indices (TAI's), based on colors of pollen grains, of 115 outcrop and 20 conventional core samples from Mesozoic and lower Tertiary rocks in the southern Coast and western Transverse Ranges, Southwestern California. The TAI's have been calibrated against previously determined vitrinite reflectance values from some of the same sample localities.

  16. Mappings with closed range and compactness

    International Nuclear Information System (INIS)

    Iyahen, S.O.; Umweni, I.

    1985-12-01

    The motivation for this note is the result of E.O. Thorp that a normed linear space E is finite dimensional if and only if every continuous linear map for E into any normed linear space has a closed range. Here, a class of Hausdorff topological groups is introduced; called r-compactifiable topological groups, they include compact groups, locally compact Abelian groups and locally convex linear topological spaces. It is proved that a group in this class which is separable, complete metrizable or locally compact, is necessarily compact if its image by a continuous group homomorphism is necessarily closed. It is deduced then that a Hausdorff locally convex is zero if its image by a continuous additive map is necessarily closed. (author)

  17. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling

    Energy Technology Data Exchange (ETDEWEB)

    Aerts, Sam, E-mail: sam.aerts@intec.ugent.be; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-10-15

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information—inside hotspots or in search of them—based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km{sup 2}. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2 dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. -- Highlights: • We present an

  18. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling

    International Nuclear Information System (INIS)

    Aerts, Sam; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-01-01

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information—inside hotspots or in search of them—based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km 2 . In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2 dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. -- Highlights: • We present an

  19. THE ALFALFA H α SURVEY. I. PROJECT DESCRIPTION AND THE LOCAL STAR FORMATION RATE DENSITY FROM THE FALL SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Sistine, Angela Van [Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Salzer, John J.; Janowiecki, Steven [Department of Astronomy, Indiana University, Bloomington, IN 47405 (United States); Sugden, Arthur [Department of Endocrinology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115 (United States); Giovanelli, Riccardo; Haynes, Martha P. [Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853 (United States); Jaskot, Anne E. [Department of Astronomy, Smith College, Northampton, MA 01063 (United States); Wilcots, Eric M. [Department of Astronomy, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2016-06-10

    The ALFALFA H α survey utilizes a large sample of H i-selected galaxies from the ALFALFA survey to study star formation (SF) in the local universe. ALFALFA H α contains 1555 galaxies with distances between ∼20 and ∼100 Mpc. We have obtained continuum-subtracted narrowband H α images and broadband R images for each galaxy, creating one of the largest homogeneous sets of H α images ever assembled. Our procedures were designed to minimize the uncertainties related to the calculation of the local SF rate density (SFRD). The galaxy sample we constructed is as close to volume-limited as possible, is a robust statistical sample, and spans a wide range of galaxy environments. In this paper, we discuss the properties of our Fall sample of 565 galaxies, our procedure for deriving individual galaxy SF rates, and our method for calculating the local SFRD. We present a preliminary value of log(SFRD[ M {sub ⊙} yr{sup −1} Mpc{sup −3}]) = −1.747 ± 0.018 (random) ±0.05 (systematic) based on the 565 galaxies in our Fall sub-sample. Compared to the weighted average of SFRD values around z ≈ 2, our local value indicates a drop in the global SFRD of a factor of 10.2 over that lookback time.

  20. Walking dynamics of the passive compass-gait model under OGY-based state-feedback control: Analysis of local bifurcations via the hybrid Poincaré map

    International Nuclear Information System (INIS)

    Gritli, Hassène; Belghith, Safya

    2017-01-01

    Highlights: • We study the passive walking dynamics of the compass-gait model under OGY-based state-feedback control. • We analyze local bifurcations via a hybrid Poincaré map. • We show exhibition of the super(sub)-critical flip bifurcation, the saddle-node(saddle) bifurcation and a saddle-flip bifurcation. • An analysis via a two-parameter bifurcation diagram is presented. • Some new hidden attractors in the controlled passive walking dynamics are displayed. - Abstract: In our previous work, we have analyzed the passive dynamic walking of the compass-gait biped model under the OGY-based state-feedback control using the impulsive hybrid nonlinear dynamics. Such study was carried out through bifurcation diagrams. It was shown that the controlled bipedal gait exhibits attractive nonlinear phenomena such as the cyclic-fold (saddle-node) bifurcation, the period-doubling (flip) bifurcation and chaos. Moreover, we revealed that, using the controlled continuous-time dynamics, we encountered a problem in finding, identifying and hence following branches of (un)stable solutions in order to characterize local bifurcations. The present paper solves such problem and then provides a further investigation of the controlled bipedal walking dynamics using the developed analytical expression of the controlled hybrid Poincaré map. Thus, we show that analysis via such Poincaré map allows to follow branches of both stable and unstable fixed points in bifurcation diagrams and hence to explore the complete dynamics of the controlled compass-gait biped model. We demonstrate the generation, other than the conventional local bifurcations in bipedal walking, i.e. the flip bifurcation and the saddle-node bifurcation, of a saddle-saddle bifurcation, a subcritical flip bifurcation and a new type of a local bifurcation, the saddle-flip bifurcation. In addition, to further understand the occurrence of the local bifurcations, we present an analysis with a two-parameter bifurcation

  1. Radiation hybrid mapping as one of the main methods of the creation of high resolution maps of human and animal genomes

    International Nuclear Information System (INIS)

    Sulimova, G.E.; Kompanijtsev, A.A.; Mojsyak, E.V.; Rakhmanaliev, Eh.R.; Klimov, E.A.; Udina, I.G.; Zakharov, I.A.

    2000-01-01

    Radiation hybrid mapping (RH mapping) is considered as one of the main method of constructing physical maps of mammalian genomes. In introduction, theoretical prerequisites of developing of the RH mapping and statistical methods of data analysis are discussed. Comparative characteristics of universal commercial panels of the radiation hybrid somatic cells (RH panels) are shown. In experimental part of the work, RH mapping is used to localize nucleotide sequences adjacent to Not I sites of human chromosome 3 with the aim to integrate contig map of Nor I clones to comprehensive maps of human genome. Five nucleotide sequences adjacent to the sites of integration of papilloma virus in human genome and expressed in the cells of cervical cancer involved localized. It is demonstrated that the region 13q14.3-q21.1 was enriched with nucleotide sequences involved in the processes of carcinogenesis. RH mapping can be considered as one of the most perspective applications of modern radiation biology in the field of molecular genetics, that is, in constructing physical maps of mammalian genomes with high resolution level [ru

  2. [An AIDS-related cognitive map in a sample of drug abusers in Buenos Aires City].

    Science.gov (United States)

    Kornblit, A L; Bilyk, A

    1990-01-01

    This paper is an approach to AIDS as a topic among a drug abusers sample of the city of Buenos Aires. Research was carried out on the basis of a qualitative methodology. In an attempt at surveying opinions and attitudes of such a sample as regards AIDS (i.e. subjects' cognitive map), 21 drug abusers from three different rehabilitation programs operating in the B.A. area were interviewed. On the basis of the research performed, the authors elaborate communication strategies among drug abusers that would be helpful for authorities engaged in AIDS prevention to adopt. To boost a strategy likely to break up the AIDS-drug association existing in the mind of many an abuser would be highly advisable so that a separation be settled between both representations, thus giving drug abusers a higher motivation for self-care practice.

  3. Integration of anatomical and external response mappings explains crossing effects in tactile localization: A probabilistic modeling approach.

    Science.gov (United States)

    Badde, Stephanie; Heed, Tobias; Röder, Brigitte

    2016-04-01

    To act upon a tactile stimulus its original skin-based, anatomical spatial code has to be transformed into an external, posture-dependent reference frame, a process known as tactile remapping. When the limbs are crossed, anatomical and external location codes are in conflict, leading to a decline in tactile localization accuracy. It is unknown whether this impairment originates from the integration of the resulting external localization response with the original, anatomical one or from a failure of tactile remapping in crossed postures. We fitted probabilistic models based on these diverging accounts to the data from three tactile localization experiments. Hand crossing disturbed tactile left-right location choices in all experiments. Furthermore, the size of these crossing effects was modulated by stimulus configuration and task instructions. The best model accounted for these results by integration of the external response mapping with the original, anatomical one, while applying identical integration weights for uncrossed and crossed postures. Thus, the model explained the data without assuming failures of remapping. Moreover, performance differences across tasks were accounted for by non-individual parameter adjustments, indicating that individual participants' task adaptation results from one common functional mechanism. These results suggest that remapping is an automatic and accurate process, and that the observed localization impairments in touch result from a cognitively controlled integration process that combines anatomically and externally coded responses.

  4. A technique for visualization and mapping of local cartilage thickness changes in MR images of osteoarthritic knee

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Quanxu, E-mail: gequanxu@yahoo.com.cn [Department of Radiology, Weihai Municipal Hospital, Weihai City, Shandong Province, 164200 (China); Cheng, Yuanzhi, E-mail: yzcheng@hitwh.edu.cn [School of Computer Science and Technology, Harbin Institute of Technology, Harbin, 150001 (China); Bi, Kesen, E-mail: whbks@yahoo.com.cn [Department of Radiology, Weihai Municipal Hospital, Weihai City, Shandong Province, 164200 (China); Guo, Changyong, E-mail: hit_gcy@163.com [School of Computer Science and Technology, Harbin Institute of Technology, Harbin, 150001 (China); Bai, Jing, E-mail: deabj@tsinghua.edu.cn [Department of Biomedical Engineering, School of Medicine, Tsinghua University, China B209, Medical School Building, Tsinghua University, Beijing, 100084 (China); Tamura, Shinichi, E-mail: tamuras@nblmt.jp [Center for Advanced Medical Engineering and Informatics, Osaka University, D11, 2-2, Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2012-11-15

    Purpose: The aim of this paper is to describe a technique for the visualization and mapping of focal, local cartilage thickness changes over time in magnetic resonance images of osteoarthritic knee. Methods: Magnetic resonance imaging was performed in 25 fresh frozen pig knee joints and 15 knees of patients with borderline to mild osteoarthritis (51.2 {+-} 6.3 years). Cartilage and corresponding bone structures were extracted by semi-automatic segmentation. Each point in the bone surface which was part of the bone-cartilage interface was assigned a cartilage thickness value. Cartilage thicknesses were computed for each point in the bone-cartilage interfaces and transferred to the bone surfaces. Moreover, we developed a three dimensional registration method for the identification of anatomically corresponding points of the bone surface to quantify local cartilage thickness changes. One of the main advantages of our method compared to other studies in the field of registration is a global optimization algorithm that does not require any initialization. Results and conclusion: The registration accuracy was 0.93 {+-} 0.05 mm (less than a voxel of magnetic resonance data). Local cartilage thickness changes were seen as having follow-up clinical study for detecting local changes in cartilage thickness. Experiment results suggest that our method was sufficiently accurate and effective for monitoring knee joint diseases.

  5. Hypocalcemic stimulation and nonselective venous sampling for localizing parathyroid adenomas: work in progress.

    Science.gov (United States)

    Doppman, J L; Skarulis, M C; Chang, R; Alexander, H R; Bartlett, D; Libutti, S K; Marx, S J; Spiegel, A M

    1998-07-01

    To evaluate whether the release of parathyroid hormone (PTH) from parathyroid tumors during selective parathyroid arteriography can help localize the tumors. In 20 patients (six men, 14 women; age range, 24-72 years) with parathyroid tumors undergoing parathyroid arteriography after failed surgery, serial measurements of PTH were obtained during selective arteriography with nonionic contrast material. PTH levels were measured in the superior vena cava (SVC) before and at varying times from 20 to 120 seconds after arteriography. A 1.4-fold increase in the PTH level of the postarteriographic SVC samples enabled correct prediction of the site of adenoma in 13 of the 20 patients (65%). Of nine patients with positive arteriograms, eight had positive results of postarteriographic sampling. Of 11 patients with negative arteriograms, five had positive results of postarteriographic sampling. Sampling the SVC for PTH gradients after selective parathyroid arteriography correctly indicated the site of the adenoma in 13 of 20 patients (65%).

  6. Putting Chronic Disease on the Map: Building GIS Capacity in State and Local Health Departments

    Science.gov (United States)

    Casper, Michele; Tootoo, Joshua; Schieb, Linda

    2013-01-01

    Techniques based on geographic information systems (GIS) have been widely adopted and applied in the fields of infectious disease and environmental epidemiology; their use in chronic disease programs is relatively new. The Centers for Disease Control and Prevention’s Division for Heart Disease and Stroke Prevention is collaborating with the National Association of Chronic Disease Directors and the University of Michigan to provide health departments with capacity to integrate GIS into daily operations, which support priorities for surveillance and prevention of chronic diseases. So far, 19 state and 7 local health departments participated in this project. On the basis of these participants’ experiences, we describe our training strategy and identify high-impact GIS skills that can be mastered and applied over a short time in support of chronic disease surveillance. We also describe the web-based resources in the Chronic Disease GIS Exchange that were produced on the basis of this training and are available to anyone interested in GIS and chronic disease (www.cdc.gov/DHDSP/maps/GISX). GIS offers diverse sets of tools that promise increased productivity for chronic disease staff of state and local health departments. PMID:23786907

  7. Putting chronic disease on the map: building GIS capacity in state and local health departments.

    Science.gov (United States)

    Miranda, Marie Lynn; Casper, Michele; Tootoo, Joshua; Schieb, Linda

    2013-06-20

    Techniques based on geographic information systems (GIS) have been widely adopted and applied in the fields of infectious disease and environmental epidemiology; their use in chronic disease programs is relatively new. The Centers for Disease Control and Prevention's Division for Heart Disease and Stroke Prevention is collaborating with the National Association of Chronic Disease Directors and the University of Michigan to provide health departments with capacity to integrate GIS into daily operations, which support priorities for surveillance and prevention of chronic diseases. So far, 19 state and 7 local health departments participated in this project. On the basis of these participants' experiences, we describe our training strategy and identify high-impact GIS skills that can be mastered and applied over a short time in support of chronic disease surveillance. We also describe the web-based resources in the Chronic Disease GIS Exchange that were produced on the basis of this training and are available to anyone interested in GIS and chronic disease (www.cdc.gov/DHDSP/maps/GISX). GIS offers diverse sets of tools that promise increased productivity for chronic disease staff of state and local health departments.

  8. Mapping aerial metal deposition in metropolitan areas from tree bark: a case study in Sheffield, England.

    Science.gov (United States)

    Schelle, E; Rawlins, B G; Lark, R M; Webster, R; Staton, I; McLeod, C W

    2008-09-01

    We investigated the use of metals accumulated on tree bark for mapping their deposition across metropolitan Sheffield by sampling 642 trees of three common species. Mean concentrations of metals were generally an order of magnitude greater than in samples from a remote uncontaminated site. We found trivially small differences among tree species with respect to metal concentrations on bark, and in subsequent statistical analyses did not discriminate between them. We mapped the concentrations of As, Cd and Ni by lognormal universal kriging using parameters estimated by residual maximum likelihood (REML). The concentrations of Ni and Cd were greatest close to a large steel works, their probable source, and declined markedly within 500 m of it and from there more gradually over several kilometres. Arsenic was much more evenly distributed, probably as a result of locally mined coal burned in domestic fires for many years. Tree bark seems to integrate airborne pollution over time, and our findings show that sampling and analysing it are cost-effective means of mapping and identifying sources.

  9. Local entropy as a measure for sampling solutions in constraint satisfaction problems

    International Nuclear Information System (INIS)

    Baldassi, Carlo; Ingrosso, Alessandro; Lucibello, Carlo; Saglietti, Luca; Zecchina, Riccardo

    2016-01-01

    We introduce a novel entropy-driven Monte Carlo (EdMC) strategy to efficiently sample solutions of random constraint satisfaction problems (CSPs). First, we extend a recent result that, using a large-deviation analysis, shows that the geometry of the space of solutions of the binary perceptron learning problem (a prototypical CSP), contains regions of very high-density of solutions. Despite being sub-dominant, these regions can be found by optimizing a local entropy measure. Building on these results, we construct a fast solver that relies exclusively on a local entropy estimate, and can be applied to general CSPs. We describe its performance not only for the perceptron learning problem but also for the random K-satisfiabilty problem (another prototypical CSP with a radically different structure), and show numerically that a simple zero-temperature Metropolis search in the smooth local entropy landscape can reach sub-dominant clusters of optimal solutions in a small number of steps, while standard Simulated Annealing either requires extremely long cooling procedures or just fails. We also discuss how the EdMC can heuristically be made even more efficient for the cases we studied. (paper: disordered systems, classical and quantum)

  10. Exploration and Discovery through Maps: Teaching Science with Technology

    Science.gov (United States)

    Online maps have the power to bring students closer to their local natural environments. EnviroAtlas is an interactive, web-based tool that was designed by the EPA and its partners to provide access to maps that show the status of the local environment and social elements of an ...

  11. Comparison of prevalence estimation of Mycobacterium avium subsp. paratuberculosis infection by sampling slaughtered cattle with macroscopic lesions vs. systematic sampling.

    Science.gov (United States)

    Elze, J; Liebler-Tenorio, E; Ziller, M; Köhler, H

    2013-07-01

    The objective of this study was to identify the most reliable approach for prevalence estimation of Mycobacterium avium ssp. paratuberculosis (MAP) infection in clinically healthy slaughtered cattle. Sampling of macroscopically suspect tissue was compared to systematic sampling. Specimens of ileum, jejunum, mesenteric and caecal lymph nodes were examined for MAP infection using bacterial microscopy, culture, histopathology and immunohistochemistry. MAP was found most frequently in caecal lymph nodes, but sampling more tissues optimized the detection rate. Examination by culture was most efficient while combination with histopathology increased the detection rate slightly. MAP was detected in 49/50 animals with macroscopic lesions representing 1.35% of the slaughtered cattle examined. Of 150 systematically sampled macroscopically non-suspect cows, 28.7% were infected with MAP. This indicates that the majority of MAP-positive cattle are slaughtered without evidence of macroscopic lesions and before clinical signs occur. For reliable prevalence estimation of MAP infection in slaughtered cattle, systematic random sampling is essential.

  12. Geometry of the local equivalence of states

    Energy Technology Data Exchange (ETDEWEB)

    Sawicki, A; Kus, M, E-mail: assawi@cft.edu.pl, E-mail: marek.kus@cft.edu.pl [Center for Theoretical Physics, Polish Academy of Sciences, Al Lotnikow 32/46, 02-668 Warszawa (Poland)

    2011-12-09

    We present a description of locally equivalent states in terms of symplectic geometry. Using the moment map between local orbits in the space of states and coadjoint orbits of the local unitary group, we reduce the problem of local unitary equivalence to an easy part consisting of identifying the proper coadjoint orbit and a harder problem of the geometry of fibers of the moment map. We give a detailed analysis of the properties of orbits of 'equally entangled states'. In particular, we show connections between certain symplectic properties of orbits such as their isotropy and coisotropy with effective criteria of local unitary equivalence. (paper)

  13. Distributed Monocular SLAM for Indoor Map Building

    OpenAIRE

    Ruwan Egodagamage; Mihran Tuceryan

    2017-01-01

    Utilization and generation of indoor maps are critical elements in accurate indoor tracking. Simultaneous Localization and Mapping (SLAM) is one of the main techniques for such map generation. In SLAM an agent generates a map of an unknown environment while estimating its location in it. Ubiquitous cameras lead to monocular visual SLAM, where a camera is the only sensing device for the SLAM process. In modern applications, multiple mobile agents may be involved in the generation of such maps,...

  14. Convenience Sampling of Children Presenting to Hospital-Based Outpatient Clinics to Estimate Childhood Obesity Levels in Local Surroundings.

    Science.gov (United States)

    Gilliland, Jason; Clark, Andrew F; Kobrzynski, Marta; Filler, Guido

    2015-07-01

    Childhood obesity is a critical public health matter associated with numerous pediatric comorbidities. Local-level data are required to monitor obesity and to help administer prevention efforts when and where they are most needed. We hypothesized that samples of children visiting hospital clinics could provide representative local population estimates of childhood obesity using data from 2007 to 2013. Such data might provide more accurate, timely, and cost-effective obesity estimates than national surveys. Results revealed that our hospital-based sample could not serve as a population surrogate. Further research is needed to confirm this finding.

  15. The Complete Local Volume Groups Sample - I. Sample selection and X-ray properties of the high-richness subsample

    Science.gov (United States)

    O'Sullivan, Ewan; Ponman, Trevor J.; Kolokythas, Konstantinos; Raychaudhury, Somak; Babul, Arif; Vrtilek, Jan M.; David, Laurence P.; Giacintucci, Simona; Gitti, Myriam; Haines, Chris P.

    2017-12-01

    We present the Complete Local-Volume Groups Sample (CLoGS), a statistically complete optically selected sample of 53 groups within 80 Mpc. Our goal is to combine X-ray, radio and optical data to investigate the relationship between member galaxies, their active nuclei and the hot intra-group medium (IGM). We describe sample selection, define a 26-group high-richness subsample of groups containing at least four optically bright (log LB ≥ 10.2 LB⊙) galaxies, and report the results of XMM-Newton and Chandra observations of these systems. We find that 14 of the 26 groups are X-ray bright, possessing a group-scale IGM extending at least 65 kpc and with luminosity >1041 erg s-1, while a further three groups host smaller galaxy-scale gas haloes. The X-ray bright groups have masses in the range M500 ≃ 0.5-5 × 1013 M⊙, based on system temperatures of 0.4-1.4 keV, and X-ray luminosities in the range 2-200 × 1041 erg s-1. We find that ∼53-65 per cent of the X-ray bright groups have cool cores, a somewhat lower fraction than found by previous archival surveys. Approximately 30 per cent of the X-ray bright groups show evidence of recent dynamical interactions (mergers or sloshing), and ∼35 per cent of their dominant early-type galaxies host active galactic nuclei with radio jets. We find no groups with unusually high central entropies, as predicted by some simulations, and confirm that CLoGS is in principle capable of detecting such systems. We identify three previously unrecognized groups, and find that they are either faint (LX, R500 < 1042 erg s-1) with no concentrated cool core, or highly disturbed. This leads us to suggest that ∼20 per cent of X-ray bright groups in the local universe may still be unidentified.

  16. Using local symmetry for landmark selection

    OpenAIRE

    Kootstra, Geert; de Jong, Sjoerd; Schomaker, Lambert R. B.

    2009-01-01

    Most visual Simultaneous Localization And Mapping (SLAM) methods use interest points as landmarks in their maps of the environment. Often the interest points are detected using contrast features, for instance those of the Scale Invariant Feature Transform (SIFT). The SIFT interest points, however, have problems with stability, and noise robustness. Taking our inspiration from human vision, we therefore propose the use of local symmetry to select interest points. Our method, the MUlti-scale Sy...

  17. Autonomous Sampling Platform Development: Radiological Contamination Mapping at SRS

    International Nuclear Information System (INIS)

    Moya, Nicholas; Whiteside, Tad

    2016-01-01

    From 1961 to 1964, radioactive elements were released from the Savannah River Site into local bodies of water via cooling water charges from the reactors on site. In 1983, the extent of the radioactive contamination was first studied, and elements such as 137 Cs, 90 Sr, 238 Pu, 241 Am, 244 Cm, and tritium were found to have seeped from local bodies of water into sediment and the surrounding flora and fauna. The current method of tracking and monitoring radioactive contamination at the SRS is to gather samples and conduct measurements in a laboratory. A cheaper, and safer, method to conduct such measurements would be to automate the process by using an autonomous boat that can travel to locations, conduct measurements, and return home all without human intervention. To introduce this idea, the construction of an autonomous boat prototype was completed to demonstrate the practicality and feasibility of such an idea. The prototype travels to a set of waypoints, stops at each waypoint, and returns when all waypoints have been reached. It does this by employing a simple battery-powered boat with an Arduino controller that steers the boat using a steering algorithm incorporated into a Proportional Integral Derivative (PID) function. A total of three tests were conducted at two different bodies of water; and after working out some hardware problems, the boat drone was able to successfully steer and reach all programmed waypoints. With the prototype complete, the next steps to realizing the final product of the boat drone will include adopting a processing unit with higher-bit architecture, using a bigger boat with a more powerful trolling motor, and incorporating a solar panel for continuous power and round-the-clock performance.

  18. Autonomous Sampling Platform Development: Radiological Contamination Mapping at SRS

    Energy Technology Data Exchange (ETDEWEB)

    Moya, Nicholas [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Whiteside, Tad [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-01

    From 1961 to 1964, radioactive elements were released from the Savannah River Site into local bodies of water via cooling water charges from the reactors on site. In 1983, the extent of the radioactive contamination was first studied, and elements such as 137Cs, 90Sr, 238Pu, 241Am, 244Cm, and tritium were found to have seeped from local bodies of water into sediment and the surrounding flora and fauna. The current method of tracking and monitoring radioactive contamination at the SRS is to gather samples and conduct measurements in a laboratory. A cheaper, and safer, method to conduct such measurements would be to automate the process by using an autonomous boat that can travel to locations, conduct measurements, and return home all without human intervention. To introduce this idea, the construction of an autonomous boat prototype was completed to demonstrate the practicality and feasibility of such an idea. The prototype travels to a set of waypoints, stops at each waypoint, and returns when all waypoints have been reached. It does this by employing a simple battery-powered boat with an Arduino controller that steers the boat using a steering algorithm incorporated into a Proportional Integral Derivative (PID) function. A total of three tests were conducted at two different bodies of water; and after working out some hardware problems, the boat drone was able to successfully steer and reach all programmed waypoints. With the prototype complete, the next steps to realizing the final product of the boat drone will include adopting a processing unit with higher-bit architecture, using a bigger boat with a more powerful trolling motor, and incorporating a solar panel for continuous power and round-the-clock performance.

  19. Conductance maps of quantum rings due to a local potential perturbation.

    Science.gov (United States)

    Petrović, M D; Peeters, F M; Chaves, A; Farias, G A

    2013-12-11

    We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the ϕ0 periodic Aharonov-Bohm oscillation pattern into a ϕ0/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total conductance map.

  20. ReactionMap: an efficient atom-mapping algorithm for chemical reactions.

    Science.gov (United States)

    Fooshee, David; Andronico, Alessio; Baldi, Pierre

    2013-11-25

    Large databases of chemical reactions provide new data-mining opportunities and challenges. Key challenges result from the imperfect quality of the data and the fact that many of these reactions are not properly balanced or atom-mapped. Here, we describe ReactionMap, an efficient atom-mapping algorithm. Our approach uses a combination of maximum common chemical subgraph search and minimization of an assignment cost function derived empirically from training data. We use a set of over 259,000 balanced atom-mapped reactions from the SPRESI commercial database to train the system, and we validate it on random sets of 1000 and 17,996 reactions sampled from this pool. These large test sets represent a broad range of chemical reaction types, and ReactionMap correctly maps about 99% of the atoms and about 96% of the reactions, with a mean time per mapping of 2 s. Most correctly mapped reactions are mapped with high confidence. Mapping accuracy compares favorably with ChemAxon's AutoMapper, versions 5 and 6.1, and the DREAM Web tool. These approaches correctly map 60.7%, 86.5%, and 90.3% of the reactions, respectively, on the same data set. A ReactionMap server is available on the ChemDB Web portal at http://cdb.ics.uci.edu .

  1. New GIS approaches to wild land mapping in Europe

    Science.gov (United States)

    Steffen Fritz; Steve Carver; Linda See

    2000-01-01

    This paper outlines modifications and new approaches to wild land mapping developed specifically for the United Kingdom and European areas. In particular, national level reconnaissance and local level mapping of wild land in the UK and Scotland are presented. A national level study for the UK is undertaken, and a local study focuses on the Cairngorm Mountains in...

  2. Mapping local singularities using magnetic data to investigate the volcanic rocks of the Qikou depression, Dagang oilfield, eastern China

    Directory of Open Access Journals (Sweden)

    G. Chen

    2013-07-01

    Full Text Available The spatial structural characteristics of geological anomaly, including singularity and self-similarity, can be analysed using fractal or multifractal modelling. Here we apply the multifractal methods to potential fields to demonstrate that singularities can characterise geological bodies, including rock density and magnetic susceptibility. In addition to enhancing weak gravity and magnetic anomalies with respect to either strong or weak background levels, the local singularity index (α ≈ 2 can be used to delineate the edges of geological bodies. Two models were established to evaluate the effectiveness of mapping singularities for extracting weak anomalies and delineating edges of buried geological bodies. The Qikou depression of the Dagang oilfield in eastern China has been chosen as a study area for demonstrating the extraction of weak anomalies of volcanic rocks, using the singularity mapping technique to analyse complex magnetic anomalies caused by complex geological background. The results have shown that the singularities of magnetic data mapped in the paper are associated with buried volcanic rocks, which have been verified by both drilling and seismic survey, and the S–N and E–W faults in the region. The targets delineated for deeply seated faults and volcanic rocks in the Qikou depression should be further investigated for the potential application in undiscovered oil and gas reservoirs exploration.

  3. Vision-based mapping with cooperative robots

    Science.gov (United States)

    Little, James J.; Jennings, Cullen; Murray, Don

    1998-10-01

    Two stereo-vision-based mobile robots navigate and autonomously explore their environment safely while building occupancy grid maps of the environment. The robots maintain position estimates within a global coordinate frame using landmark recognition. This allows them to build a common map by sharing position information and stereo data. Stereo vision processing and map updates are done at 3 Hz and the robots move at speeds of 200 cm/s. Cooperative mapping is achieved through autonomous exploration of unstructured and dynamic environments. The map is constructed conservatively, so as to be useful for collision-free path planning. Each robot maintains a separate copy of a shared map, and then posts updates to the common map when it returns to observe a landmark at home base. Issues include synchronization, mutual localization, navigation, exploration, registration of maps, merging repeated views (fusion), centralized vs decentralized maps.

  4. Mapping how local perturbations influence systems-level brain dynamics.

    Science.gov (United States)

    Gollo, Leonardo L; Roberts, James A; Cocchi, Luca

    2017-10-15

    The human brain exhibits a distinct spatiotemporal organization that supports brain function and can be manipulated via local brain stimulation. Such perturbations to local cortical dynamics are globally integrated by distinct neural systems. However, it remains unclear how local changes in neural activity affect large-scale system dynamics. Here, we briefly review empirical and computational studies addressing how localized perturbations affect brain activity. We then systematically analyze a model of large-scale brain dynamics, assessing how localized changes in brain activity at the different sites affect whole-brain dynamics. We find that local stimulation induces changes in brain activity that can be summarized by relatively smooth tuning curves, which relate a region's effectiveness as a stimulation site to its position within the cortical hierarchy. Our results also support the notion that brain hubs, operating in a slower regime, are more resilient to focal perturbations and critically contribute to maintain stability in global brain dynamics. In contrast, perturbations of peripheral regions, characterized by faster activity, have greater impact on functional connectivity. As a parallel with this region-level result, we also find that peripheral systems such as the visual and sensorimotor networks were more affected by local perturbations than high-level systems such as the cingulo-opercular network. Our findings highlight the importance of a periphery-to-core hierarchy to determine the effect of local stimulation on the brain network. This study also provides novel resources to orient empirical work aiming at manipulating functional connectivity using non-invasive brain stimulation. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Modeling non-locality of plasmonic excitations with a fictitious film

    Science.gov (United States)

    Kong, Jiantao; Shvonski, Alexander; Kempa, Krzysztof

    Non-local effects, requiring a wavevector (q) dependent dielectric response are becoming increasingly important in studies of plasmonic and metamaterial structures. The phenomenological hydrodynamic approximation (HDA) is the simplest, and most often used model, but it often fails. We show that the d-function formalism, exact to first order in q, is a powerful and simple-to-use alternative. Recently, we developed a mapping of the d-function formalism into a purely local fictitious film. This geometric mapping allows for non-local extensions of any local calculation scheme, including FDTD. We demonstrate here, that such mapped FDTD simulation of metallic nanoclusters agrees very well with various experiments.

  6. An Integrated Tone Mapping for High Dynamic Range Image Visualization

    Science.gov (United States)

    Liang, Lei; Pan, Jeng-Shyang; Zhuang, Yongjun

    2018-01-01

    There are two type tone mapping operators for high dynamic range (HDR) image visualization. HDR image mapped by perceptual operators have strong sense of reality, but will lose local details. Empirical operators can maximize local detail information of HDR image, but realism is not strong. A common tone mapping operator suitable for all applications is not available. This paper proposes a novel integrated tone mapping framework which can achieve conversion between empirical operators and perceptual operators. In this framework, the empirical operator is rendered based on improved saliency map, which simulates the visual attention mechanism of the human eye to the natural scene. The results of objective evaluation prove the effectiveness of the proposed solution.

  7. Puzzle Imaging: Using Large-Scale Dimensionality Reduction Algorithms for Localization.

    Science.gov (United States)

    Glaser, Joshua I; Zamft, Bradley M; Church, George M; Kording, Konrad P

    2015-01-01

    Current high-resolution imaging techniques require an intact sample that preserves spatial relationships. We here present a novel approach, "puzzle imaging," that allows imaging a spatially scrambled sample. This technique takes many spatially disordered samples, and then pieces them back together using local properties embedded within the sample. We show that puzzle imaging can efficiently produce high-resolution images using dimensionality reduction algorithms. We demonstrate the theoretical capabilities of puzzle imaging in three biological scenarios, showing that (1) relatively precise 3-dimensional brain imaging is possible; (2) the physical structure of a neural network can often be recovered based only on the neural connectivity matrix; and (3) a chemical map could be reproduced using bacteria with chemosensitive DNA and conjugative transfer. The ability to reconstruct scrambled images promises to enable imaging based on DNA sequencing of homogenized tissue samples.

  8. Tree Cover Mapping Tool—Documentation and user manual

    Science.gov (United States)

    Cotillon, Suzanne E.; Mathis, Melissa L.

    2016-06-02

    The Tree Cover Mapping (TCM) tool was developed by scientists at the U.S. Geological Survey Earth Resources Observation and Science Center to allow a user to quickly map tree cover density over large areas using visual interpretation of high resolution imagery within a geographic information system interface. The TCM tool uses a systematic sample grid to produce maps of tree cover. The TCM tool allows the user to define sampling parameters to estimate tree cover within each sample unit. This mapping method generated the first on-farm tree cover maps of vast regions of Niger and Burkina Faso. The approach contributes to implementing integrated landscape management to scale up re-greening and restore degraded land in the drylands of Africa. The TCM tool is easy to operate, practical, and can be adapted to many other applications such as crop mapping, settlements mapping, or other features. This user manual provides step-by-step instructions for installing and using the tool, and creating tree cover maps. Familiarity with ArcMap tools and concepts is helpful for using the tool.

  9. Optimized preparation of urine samples for two-dimensional electrophoresis and initial application to patient samples

    DEFF Research Database (Denmark)

    Lafitte, Daniel; Dussol, Bertrand; Andersen, Søren

    2002-01-01

    OBJECTIVE: We optimized of the preparation of urinary samples to obtain a comprehensive map of urinary proteins of healthy subjects and then compared this map with the ones obtained with patient samples to show that the pattern was specific of their kidney disease. DESIGN AND METHODS: The urinary...

  10. Adaptive local learning in sampling based motion planning for protein folding.

    Science.gov (United States)

    Ekenna, Chinwe; Thomas, Shawna; Amato, Nancy M

    2016-08-01

    Simulating protein folding motions is an important problem in computational biology. Motion planning algorithms, such as Probabilistic Roadmap Methods, have been successful in modeling the folding landscape. Probabilistic Roadmap Methods and variants contain several phases (i.e., sampling, connection, and path extraction). Most of the time is spent in the connection phase and selecting which variant to employ is a difficult task. Global machine learning has been applied to the connection phase but is inefficient in situations with varying topology, such as those typical of folding landscapes. We develop a local learning algorithm that exploits the past performance of methods within the neighborhood of the current connection attempts as a basis for learning. It is sensitive not only to different types of landscapes but also to differing regions in the landscape itself, removing the need to explicitly partition the landscape. We perform experiments on 23 proteins of varying secondary structure makeup with 52-114 residues. We compare the success rate when using our methods and other methods. We demonstrate a clear need for learning (i.e., only learning methods were able to validate against all available experimental data) and show that local learning is superior to global learning producing, in many cases, significantly higher quality results than the other methods. We present an algorithm that uses local learning to select appropriate connection methods in the context of roadmap construction for protein folding. Our method removes the burden of deciding which method to use, leverages the strengths of the individual input methods, and it is extendable to include other future connection methods.

  11. The Mapping X-ray Fluorescence Spectrometer (MapX)

    Science.gov (United States)

    Sarrazin, P.; Blake, D. F.; Marchis, F.; Bristow, T.; Thompson, K.

    2017-12-01

    Many planetary surface processes leave traces of their actions as features in the size range 10s to 100s of microns. The Mapping X-ray Fluorescence Spectrometer (MapX) will provide elemental imaging at 100 micron spatial resolution, yielding elemental chemistry at a scale where many relict physical, chemical, or biological features can be imaged and interpreted in ancient rocks on planetary bodies and planetesimals. MapX is an arm-based instrument positioned on a rock or regolith with touch sensors. During an analysis, an X-ray source (tube or radioisotope) bombards the sample with X-rays or alpha-particles / gamma-rays, resulting in sample X-ray Fluorescence (XRF). X-rays emitted in the direction of an X-ray sensitive CCD imager pass through a 1:1 focusing lens (X-ray micro-pore Optic (MPO)) that projects a spatially resolved image of the X-rays onto the CCD. The CCD is operated in single photon counting mode so that the energies and positions of individual X-ray photons are recorded. In a single analysis, several thousand frames are both stored and processed in real-time. Higher level data products include single-element maps with a lateral spatial resolution of 100 microns and quantitative XRF spectra from ground- or instrument- selected Regions of Interest (ROI). XRF spectra from ROI are compared with known rock and mineral compositions to extrapolate the data to rock types and putative mineralogies. When applied to airless bodies and implemented with an appropriate radioisotope source for alpha-particle excitation, MapX will be able to analyze biogenic elements C, N, O, P, S, in addition to the cations of the rock-forming elements >Na, accessible with either X-ray or gamma-ray excitation. The MapX concept has been demonstrated with a series of lab-based prototypes and is currently under refinement and TRL maturation.

  12. Information-Fusion Methods Based Simultaneous Localization and Mapping for Robot Adapting to Search and Rescue Postdisaster Environments

    Directory of Open Access Journals (Sweden)

    Hongling Wang

    2018-01-01

    Full Text Available The first application of utilizing unique information-fusion SLAM (IF-SLAM methods is developed for mobile robots performing simultaneous localization and mapping (SLAM adapting to search and rescue (SAR environments in this paper. Several fusion approaches, parallel measurements filtering, exploration trajectories fusing, and combination sensors’ measurements and mobile robots’ trajectories, are proposed. The novel integration particle filter (IPF and optimal improved EKF (IEKF algorithms are derived for information-fusion systems to perform SLAM task in SAR scenarios. The information-fusion architecture consists of multirobots and multisensors (MAM; multiple robots mount on-board laser range finder (LRF sensors, localization sonars, gyro odometry, Kinect-sensor, RGB-D camera, and other proprioceptive sensors. This information-fusion SLAM (IF-SLAM is compared with conventional methods, which indicates that fusion trajectory is more consistent with estimated trajectories and real observation trajectories. The simulations and experiments of SLAM process are conducted in both cluttered indoor environment and outdoor collapsed unstructured scenario, and experimental results validate the effectiveness of the proposed information-fusion methods in improving SLAM performances adapting to SAR scenarios.

  13. The role of house surveys in geological radon potential mapping

    International Nuclear Information System (INIS)

    Ball, K.

    1997-01-01

    Because radon levels vary widely between apparently identical buildings on the same geological unit, no map can predict the radon level in an individual building. Maps can, however, give the probability that a building in a particular locality is above a threshold of radon concentration such as a reference or action level. The probability may be calculated for a particular building type or for a mixture of building types. In the latter case the probability is in effect an estimate of the proportion of buildings above the threshold level. Alternatively maps can provide estimates of the mean radon levels in buildings by area. Maps showing the geographical variation in probability that new or existing building will exceed a radon reference level are used to prevent excessive exposures to radon. The information may be used in various ways, such as to target information campaigns encouraging measurement of radon levels in homes or to modify regulations for new buildings. The data which are used to provide the estimates of the proportion of buildings above a threshold may be radon measurements results from a sample of buildings, or may be indirect indicators such as ground radium concentrations, emanation coefficients and permeability measurements. Consistency in radon measurement protocols and detailed positional information are prerequisites for mapping radon prone areas based upon house data. Grouping building radon measurements by geological formation and superficial cover can produce radon potential maps which are more spatially accurate than grid square maps and more accurate in estimating numbers of homes affected than mapping based only on measuring geological and pedagogical properties

  14. Freeze-substitution methods for Ni localization and quantitative analysis in Berkheya coddii leaves by means of PIXE

    International Nuclear Information System (INIS)

    Budka, D.; Mesjasz-PrzybyIowicz, J.; Tylko, G.; PrzybyIowicz, W.J.

    2005-01-01

    Leaves of Ni hyperaccumulator Berkheya coddii were chosen as a model to investigate the influence of eight freeze-substitution protocols on the Ni content and distribution. Freeze-substitution of leaf samples cryofixed by high-pressure freezing was carried out in dry acetone, methanol, diethyl ether and tetrahydrofuran. The same substitution media were also used with dimethylglyoxime added as a precipitation reagent. The samples were infiltrated and embedded in Spurr's resin. Micro-PIXE analysis of Ni concentration and localization, complemented by proton backscattering for matrix assessment, was performed using the nuclear microprobe at Materials Research Group, iThemba LABS, South Africa. True elemental maps and concentrations were obtained using GeoPIXE-II software. The results were compared with the control results obtained for the parallel air-dried samples, corrected for the water content. The highest Ni content was found in the leaf samples substituted in diethyl ether. This concentration was statistically different from the results obtained for other media. In case of diethyl ether medium Ni was mainly localized in the mesophyll tissue, and the distribution map of this element was in accordance with previous results obtained for freeze-dried and frozen-hydrated leaves of this species. The same distribution pattern was observed for specimens embedded in dry acetone, but Ni concentration was significantly lower. Tetrahydrofuran medium preserved Ni preferentially in the epidermis and vascular tissue, and the elemental map for samples embedded in this medium was distorted. Ni was almost completely washed out from samples substituted in methanol and it was thus impossible to obtain a picture of its distribution. Dimethylglyoxime did not improve the preservation of this element. These results show that diethyl ether is a suitable substitution medium for assessment of Ni concentration and distribution in leaves of B. coddii

  15. Analytical results and sample locality map for rock, stream-sediment, and soil samples, Northern and Eastern Coloado Desert BLM Resource Area, Imperial, Riverside, and San Bernardino Counties, California

    Science.gov (United States)

    King, Harley D.; Chaffee, Maurice A.

    2000-01-01

    INTRODUCTION In 1996-1998 the U.S. Geological Survey (USGS) conducted a geochemical study of the Bureau of Land Management's (BLM) 5.5 million-acre Northern and Eastern Colorado Desert Resource Area (usually referred to as the NECD in this report), Imperial, Riverside, and San Bernardino Counties, southeastern California (figure 1). This study was done in support of the BLM's Coordinated Management Plan for the area. This report presents analytical data from this study. To provide comprehensive coverage of the NECD, we compiled and examined all available geochemical data, in digital form, from previous studies in the area, and made sample-site plots to aid in determining where sample-site coverage and analyses were sufficient, which samples should be re-analyzed, and where additional sampling was needed. Previous investigations conducted in parts of the current study area included the National Uranium Resource Evaluation (NURE) program studies of the Needles and Salton Sea 1? x 2? quadrangles; USGS studies of 12 BLM Wilderness Study Areas (WSAs) (Big Maria Mountains, Chemehuevi Mountains, Chuckwalla Mountains, Coxcomb Mountains, Mecca Hills, Orocopia Mountains, Palen-McCoy, Picacho Peak, Riverside Mountains, Sheephole Valley (also known as Sheep Hole/Cadiz), Turtle Mountains, and Whipple Mountains); and USGS studies in the Needles and El Centro 1? x 2? quadrangles done during the early 1990s as part of a project to identify the regional geochemistry of southern California. Areas where we did new sampling of rocks and stream sediments are mainly in the Chocolate Mountain Aerial Gunnery Range and in Joshua Tree National Park, which extends into the west-central part of the NECD, as shown in figure 1 and figure 2. This report contains analytical data for 132 rock samples and 1,245 stream-sediment samples collected by the USGS, and 362 stream-sediment samples and 189 soil samples collected during the NURE program. All samples are from the Northern and Eastern Colorado

  16. SLAMM: Visual monocular SLAM with continuous mapping using multiple maps.

    Directory of Open Access Journals (Sweden)

    Hayyan Afeef Daoud

    Full Text Available This paper presents the concept of Simultaneous Localization and Multi-Mapping (SLAMM. It is a system that ensures continuous mapping and information preservation despite failures in tracking due to corrupted frames or sensor's malfunction; making it suitable for real-world applications. It works with single or multiple robots. In a single robot scenario the algorithm generates a new map at the time of tracking failure, and later it merges maps at the event of loop closure. Similarly, maps generated from multiple robots are merged without prior knowledge of their relative poses; which makes this algorithm flexible. The system works in real time at frame-rate speed. The proposed approach was tested on the KITTI and TUM RGB-D public datasets and it showed superior results compared to the state-of-the-arts in calibrated visual monocular keyframe-based SLAM. The mean tracking time is around 22 milliseconds. The initialization is twice as fast as it is in ORB-SLAM, and the retrieved map can reach up to 90 percent more in terms of information preservation depending on tracking loss and loop closure events. For the benefit of the community, the source code along with a framework to be run with Bebop drone are made available at https://github.com/hdaoud/ORBSLAMM.

  17. MAPPING THE SIMILARITIES OF SPECTRA: GLOBAL AND LOCALLY-BIASED APPROACHES TO SDSS GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Lawlor, David [Statistical and Applied Mathematical Sciences Institute (United States); Budavári, Tamás [Dept. of Applied Mathematics and Statistics, The Johns Hopkins University (United States); Mahoney, Michael W. [International Computer Science Institute (United States)

    2016-12-10

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors . Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  18. Mapping the Similarities of Spectra: Global and Locally-biased Approaches to SDSS Galaxies

    Science.gov (United States)

    Lawlor, David; Budavári, Tamás; Mahoney, Michael W.

    2016-12-01

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors. Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  19. MAPPING THE SIMILARITIES OF SPECTRA: GLOBAL AND LOCALLY-BIASED APPROACHES TO SDSS GALAXIES

    International Nuclear Information System (INIS)

    Lawlor, David; Budavári, Tamás; Mahoney, Michael W.

    2016-01-01

    We present a novel approach to studying the diversity of galaxies. It is based on a novel spectral graph technique, that of locally-biased semi-supervised eigenvectors . Our method introduces new coordinates that summarize an entire spectrum, similar to but going well beyond the widely used Principal Component Analysis (PCA). Unlike PCA, however, this technique does not assume that the Euclidean distance between galaxy spectra is a good global measure of similarity. Instead, we relax that condition to only the most similar spectra, and we show that doing so yields more reliable results for many astronomical questions of interest. The global variant of our approach can identify very finely numerous astronomical phenomena of interest. The locally-biased variants of our basic approach enable us to explore subtle trends around a set of chosen objects. The power of the method is demonstrated in the Sloan Digital Sky Survey Main Galaxy Sample, by illustrating that the derived spectral coordinates carry an unprecedented amount of information.

  20. Maps on large-scale air quality concentrations in the Netherlands. Report on 2010

    International Nuclear Information System (INIS)

    Velders, G.J.M.; Aben, J.M.M.; Diederen, H.S.M.A.; Drissen, E; Geilenkirchen, G.P.; Jimmink, B.A.; Koekoek, A.F.; Koelemeijer, R.B.A.; Matthijsen, J.; Peek, C.J.; Van Rijn, F.J.A.; De Vries, W.J.

    2010-06-01

    In the Netherlands, the number of locations for which the European limit values for nitrogen dioxide concentrations could be exceeded is larger than was estimated last year. The limit value, from 2015 onwards, might be exceeded along 100 to 150 kilometres of city roads and along about 100 kilometres of motorways, based on standing and proposed national and European policies, not taking local policies into account. The exceedances occur mainly in the Randstad area, along motorways around the large cities, and in streets within these cities. The number of locations is about twice as large as was estimated last year, as a result of new measurements of emissions from heavy-duty vehicles, and meeting the limit value in time may require additional national and local policies. The new estimates were based on large-scale concentration maps (called GCN maps) of air quality components, and on additional local contributions. The concentration maps provided the best possible estimate of large-scale air quality. The degree of uncertainty in local concentrations of particulate matter and nitrogen dioxide was estimated at approximately 15 to 20 per cent. This report presents the methods and emissions used for producing the GCN maps. It also shows the differences with the maps produced in 2009. These maps are used by local, provincial and other authorities to define additional local measures. The PBL would like to emphasise that uncertainties in the concentrations must be kept in mind when using these maps for planning, or when comparing concentrations with limit values. This also applies to the selecting of local measures to improve the air quality. The concentration maps are available online, at http://www.pbl.nl/gcn. Keywords: GCN; particulate matter; PM10; nitrogen dioxide; limit value. [nl

  1. Using Local Symmetry for Landmark Selection

    NARCIS (Netherlands)

    Kootstra, Gert; de Jong, Sjoerd; Schomaker, Lambert R. B.; Fritz, M; Schiele, B; Piater, JH

    2009-01-01

    Most visual Simultaneous Localization And Mapping (SLAM) methods use interest points as landmarks in their maps of the environment. Often the interest points are detected using contrast features, for instance those of the Scale Invariant Feature Transform (SIFT). The SIFT interest points, however,

  2. Mapping nanoscale effects of localized noise-source activities on photoconductive charge transports in polymer-blend films

    Science.gov (United States)

    Shekhar, Shashank; Cho, Duckhyung; Cho, Dong-Guk; Yang, Myungjae; Hong, Seunghun

    2018-05-01

    We develolped a method to directly image the nanoscale effects of localized noise-source activities on photoconducting charge transports in domain structures of phase-separated polymer-blend films of Poly(9,9-di-n-octylfluorenyl-2,7-diyl) and Poly(9,9-di-n-octylfluorene-alt-benzothiadiazole). For the imaging, current and noise maps of the polymer-blend were recorded using a conducting nanoprobe in contact with the surface, enabling the conductivity (σ) and noise-source density (N T) mappings under an external stimulus. The blend-films exhibited the phase-separation between the constituent polymers at domains level. Within a domain, high σ (low N T) and low σ (high N T) regions were observed, which could be associated with the ordered and disordered regions of a domain. In the N T maps, we observed that noise-sources strongly affected the conduction mechanism, resulting in a scaling behavior of σ ∝ {{N}{{T}}}-0.5 in both ordered and disordered regions. When a blend film was under an influence of an external stimulus such as a high bias or an illumination, an increase in the σ was observed, but that also resulted in increases in the N T as a trade-off. Interestingly, the Δσ versus ΔN T plot exhibited an unusual scaling behavior of Δσ ∝ {{Δ }}{{N}{{T}}}0.5, which is attributed to the de-trapping of carriers from deep traps by the external stimuli. In addition, we found that an external stimulus increased the conductivity at the interfaces without significantly increasing their N T, which can be the origin of the superior performances of polymer-blend based devices. These results provide valuable insight about the effects of noise-sources on nanoscale optoelectronic properties in polymer-blend films, which can be an important guideline for improving devices based on polymer-blend.

  3. Sub-sampling-based 2D localization of an impulsive acoustic source in reverberant environments

    KAUST Repository

    Omer, Muhammad

    2014-07-01

    This paper presents a robust method for two-dimensional (2D) impulsive acoustic source localization in a room environment using low sampling rates. The proposed method finds the time delay from the room impulse response (RIR) which makes it robust against room reverberations. We consider the RIR as a sparse phenomenon and apply a recently proposed sparse signal reconstruction technique called orthogonal clustering (OC) for its estimation from the sub-sampled received signal. The arrival time of the direct path signal at a pair of microphones is identified from the estimated RIR, and their difference yields the desired time delay estimate (TDE). Low sampling rates reduces the hardware and computational complexity and decreases the communication between the microphones and the centralized location. Simulation and experimental results of an actual hardware setup are presented to demonstrate the performance of the proposed technique.

  4. Sub-sampling-based 2D localization of an impulsive acoustic source in reverberant environments

    KAUST Repository

    Omer, Muhammad; Quadeer, Ahmed A; Sharawi, Mohammad S; Al-Naffouri, Tareq Y.

    2014-01-01

    This paper presents a robust method for two-dimensional (2D) impulsive acoustic source localization in a room environment using low sampling rates. The proposed method finds the time delay from the room impulse response (RIR) which makes it robust against room reverberations. We consider the RIR as a sparse phenomenon and apply a recently proposed sparse signal reconstruction technique called orthogonal clustering (OC) for its estimation from the sub-sampled received signal. The arrival time of the direct path signal at a pair of microphones is identified from the estimated RIR, and their difference yields the desired time delay estimate (TDE). Low sampling rates reduces the hardware and computational complexity and decreases the communication between the microphones and the centralized location. Simulation and experimental results of an actual hardware setup are presented to demonstrate the performance of the proposed technique.

  5. More 'mapping' in brain mapping: statistical comparison of effects

    DEFF Research Database (Denmark)

    Jernigan, Terry Lynne; Gamst, Anthony C.; Fennema-Notestine, Christine

    2003-01-01

    The term 'mapping' in the context of brain imaging conveys to most the concept of localization; that is, a brain map is meant to reveal a relationship between some condition or parameter and specific sites within the brain. However, in reality, conventional voxel-based maps of brain function......, or for that matter of brain structure, are generally constructed using analyses that yield no basis for inferences regarding the spatial nonuniformity of the effects. In the normal analysis path for functional images, for example, there is nowhere a statistical comparison of the observed effect in any voxel relative...... to that in any other voxel. Under these circumstances, strictly speaking, the presence of significant activation serves as a legitimate basis only for inferences about the brain as a unit. In their discussion of results, investigators rarely are content to confirm the brain's role, and instead generally prefer...

  6. Water-sanitation-hygiene mapping: an improved approach for data collection at local level.

    Science.gov (United States)

    Giné-Garriga, Ricard; de Palencia, Alejandro Jiménez-Fernández; Pérez-Foguet, Agustí

    2013-10-01

    Strategic planning and appropriate development and management of water and sanitation services are strongly supported by accurate and accessible data. If adequately exploited, these data might assist water managers with performance monitoring, benchmarking comparisons, policy progress evaluation, resources allocation, and decision making. A variety of tools and techniques are in place to collect such information. However, some methodological weaknesses arise when developing an instrument for routine data collection, particularly at local level: i) comparability problems due to heterogeneity of indicators, ii) poor reliability of collected data, iii) inadequate combination of different information sources, and iv) statistical validity of produced estimates when disaggregated into small geographic subareas. This study proposes an improved approach for water, sanitation and hygiene (WASH) data collection at decentralised level in low income settings, as an attempt to overcome previous shortcomings. The ultimate aim is to provide local policymakers with strong evidences to inform their planning decisions. The survey design takes the Water Point Mapping (WPM) as a starting point to record all available water sources at a particular location. This information is then linked to data produced by a household survey. Different survey instruments are implemented to collect reliable data by employing a variety of techniques, such as structured questionnaires, direct observation and water quality testing. The collected data is finally validated through simple statistical analysis, which in turn produces valuable outputs that might feed into the decision-making process. In order to demonstrate the applicability of the method, outcomes produced from three different case studies (Homa Bay District-Kenya-; Kibondo District-Tanzania-; and Municipality of Manhiça-Mozambique-) are presented. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. TRAM (Transcriptome Mapper: database-driven creation and analysis of transcriptome maps from multiple sources

    Directory of Open Access Journals (Sweden)

    Danieli Gian

    2011-02-01

    Full Text Available Abstract Background Several tools have been developed to perform global gene expression profile data analysis, to search for specific chromosomal regions whose features meet defined criteria as well as to study neighbouring gene expression. However, most of these tools are tailored for a specific use in a particular context (e.g. they are species-specific, or limited to a particular data format and they typically accept only gene lists as input. Results TRAM (Transcriptome Mapper is a new general tool that allows the simple generation and analysis of quantitative transcriptome maps, starting from any source listing gene expression values for a given gene set (e.g. expression microarrays, implemented as a relational database. It includes a parser able to assign univocal and updated gene symbols to gene identifiers from different data sources. Moreover, TRAM is able to perform intra-sample and inter-sample data normalization, including an original variant of quantile normalization (scaled quantile, useful to normalize data from platforms with highly different numbers of investigated genes. When in 'Map' mode, the software generates a quantitative representation of the transcriptome of a sample (or of a pool of samples and identifies if segments of defined lengths are over/under-expressed compared to the desired threshold. When in 'Cluster' mode, the software searches for a set of over/under-expressed consecutive genes. Statistical significance for all results is calculated with respect to genes localized on the same chromosome or to all genome genes. Transcriptome maps, showing differential expression between two sample groups, relative to two different biological conditions, may be easily generated. We present the results of a biological model test, based on a meta-analysis comparison between a sample pool of human CD34+ hematopoietic progenitor cells and a sample pool of megakaryocytic cells. Biologically relevant chromosomal segments and gene

  8. MeshSLAM: Robust Localization and Large-Scale Mapping in Barren Terrain, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Robots need to know their location to map of their surroundings but without global positioning data they need a map to identify their surroundings and estimate their...

  9. MeshSLAM: Robust Localization and Large-Scale Mapping in Barren Terrain, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Robots need to know their location to map of their surroundings but without global positioning data they need a map to identify their surroundings and estimate their...

  10. Metabarcoding of Fecal Samples to Determine Herbivore Diets: A Case Study of the Endangered Pacific Pocket Mouse.

    Science.gov (United States)

    Iwanowicz, Deborah D; Vandergast, Amy G; Cornman, Robert S; Adams, Cynthia R; Kohn, Joshua R; Fisher, Robert N; Brehme, Cheryl S

    2016-01-01

    Understanding the diet of an endangered species illuminates the animal's ecology, habitat requirements, and conservation needs. However, direct observation of diet can be difficult, particularly for small, nocturnal animals such as the Pacific pocket mouse (Heteromyidae: Perognathus longimembris pacificus). Very little is known of the dietary habits of this federally endangered rodent, hindering management and restoration efforts. We used a metabarcoding approach to identify source plants in fecal samples (N = 52) from the three remaining populations known. The internal transcribed spacers (ITS) of the nuclear ribosomal loci were sequenced following the Illumina MiSeq amplicon strategy and processed reads were mapped to reference databases. We evaluated a range of threshold mapping criteria and found the best-performing setting generally recovered two distinct mock communities in proportions similar to expectation. We tested our method on captive animals fed a known diet and recovered almost all plant sources, but found substantial heterogeneity among fecal pellets collected from the same individual at the same time. Observed richness did not increase with pooling of pellets from the same individual. In field-collected samples, we identified 4-14 plant genera in individual samples and 74 genera overall, but over 50 percent of reads mapped to just six species in five genera. We simulated the effects of sequencing error, variable read length, and chimera formation to infer taxon-specific rates of misassignment for the local flora, which were generally low with some exceptions. Richness at the species and genus levels did not reach a clear asymptote, suggesting that diet breadth remained underestimated in the current pool of samples. Large numbers of scat samples are therefore needed to make inferences about diet and resource selection in future studies of the Pacific pocket mouse. We conclude that our minimally invasive method is promising for determining herbivore

  11. Metabarcoding of Fecal Samples to Determine Herbivore Diets: A Case Study of the Endangered Pacific Pocket Mouse.

    Directory of Open Access Journals (Sweden)

    Deborah D Iwanowicz

    Full Text Available Understanding the diet of an endangered species illuminates the animal's ecology, habitat requirements, and conservation needs. However, direct observation of diet can be difficult, particularly for small, nocturnal animals such as the Pacific pocket mouse (Heteromyidae: Perognathus longimembris pacificus. Very little is known of the dietary habits of this federally endangered rodent, hindering management and restoration efforts. We used a metabarcoding approach to identify source plants in fecal samples (N = 52 from the three remaining populations known. The internal transcribed spacers (ITS of the nuclear ribosomal loci were sequenced following the Illumina MiSeq amplicon strategy and processed reads were mapped to reference databases. We evaluated a range of threshold mapping criteria and found the best-performing setting generally recovered two distinct mock communities in proportions similar to expectation. We tested our method on captive animals fed a known diet and recovered almost all plant sources, but found substantial heterogeneity among fecal pellets collected from the same individual at the same time. Observed richness did not increase with pooling of pellets from the same individual. In field-collected samples, we identified 4-14 plant genera in individual samples and 74 genera overall, but over 50 percent of reads mapped to just six species in five genera. We simulated the effects of sequencing error, variable read length, and chimera formation to infer taxon-specific rates of misassignment for the local flora, which were generally low with some exceptions. Richness at the species and genus levels did not reach a clear asymptote, suggesting that diet breadth remained underestimated in the current pool of samples. Large numbers of scat samples are therefore needed to make inferences about diet and resource selection in future studies of the Pacific pocket mouse. We conclude that our minimally invasive method is promising for

  12. Data Assimilation with Optimal Maps

    Science.gov (United States)

    El Moselhy, T.; Marzouk, Y.

    2012-12-01

    Tarek El Moselhy and Youssef Marzouk Massachusetts Institute of Technology We present a new approach to Bayesian inference that entirely avoids Markov chain simulation and sequential importance resampling, by constructing a map that pushes forward the prior measure to the posterior measure. Existence and uniqueness of a suitable measure-preserving map is established by formulating the problem in the context of optimal transport theory. The map is written as a multivariate polynomial expansion and computed efficiently through the solution of a stochastic optimization problem. While our previous work [1] focused on static Bayesian inference problems, we now extend the map-based approach to sequential data assimilation, i.e., nonlinear filtering and smoothing. One scheme involves pushing forward a fixed reference measure to each filtered state distribution, while an alternative scheme computes maps that push forward the filtering distribution from one stage to the other. We compare the performance of these schemes and extend the former to problems of smoothing, using a map implementation of the forward-backward smoothing formula. Advantages of a map-based representation of the filtering and smoothing distributions include analytical expressions for posterior moments and the ability to generate arbitrary numbers of independent uniformly-weighted posterior samples without additional evaluations of the dynamical model. Perhaps the main advantage, however, is that the map approach inherently avoids issues of sample impoverishment, since it explicitly represents the posterior as the pushforward of a reference measure, rather than with a particular set of samples. The computational complexity of our algorithm is comparable to state-of-the-art particle filters. Moreover, the accuracy of the approach is controlled via the convergence criterion of the underlying optimization problem. We demonstrate the efficiency and accuracy of the map approach via data assimilation in

  13. CRISM Multispectral and Hyperspectral Mapping Data - A Global Data Set for Hydrated Mineral Mapping

    Science.gov (United States)

    Seelos, F. P.; Hash, C. D.; Murchie, S. L.; Lim, H.

    2017-12-01

    The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is a visible through short-wave infrared hyperspectral imaging spectrometer (VNIR S-detector: 364-1055 nm; IR L-detector: 1001-3936 nm; 6.55 nm sampling) that has been in operation on the Mars Reconnaissance Orbiter (MRO) since 2006. Over the course of the MRO mission, CRISM has acquired 290,000 individual mapping observation segments (mapping strips) with a variety of observing modes and data characteristics (VNIR/IR; 100/200 m/pxl; multi-/hyper-spectral band selection) over a wide range of observing conditions (atmospheric state, observation geometry, instrument state). CRISM mapping data coverage density varies primarily with latitude and secondarily due to seasonal and operational considerations. The aggregate global IR mapping data coverage currently stands at 85% ( 80% at the equator with 40% repeat sampling), which is sufficient spatial sampling density to support the assembly of empirically optimized radiometrically consistent mapping mosaic products. The CRISM project has defined a number of mapping mosaic data products (e.g. Multispectral Reduced Data Record (MRDR) map tiles) with varying degrees of observation-specific processing and correction applied prior to mosaic assembly. A commonality among the mosaic products is the presence of inter-observation radiometric discrepancies which are traceable to variable observation circumstances or associated atmospheric/photometric correction residuals. The empirical approach to radiometric reconciliation leverages inter-observation spatial overlaps and proximal relationships to construct a graph that encodes the mosaic structure and radiometric discrepancies. The graph theory abstraction allows the underling structure of the msaic to be evaluated and the corresponding optimization problem configured so it is well-posed. Linear and non-linear least squares optimization is then employed to derive a set of observation- and wavelength- specific model

  14. Multi-phase EBSD mapping and local texture analysis in NdFeB sintered magnets

    Energy Technology Data Exchange (ETDEWEB)

    Woodcock, T.G., E-mail: t.woodcock@ifw-dresden.de [IFW Dresden, Institute for Metallic Materials, PO Box 270116, 01171 Dresden (Germany); Gutfleisch, O. [IFW Dresden, Institute for Metallic Materials, PO Box 270116, 01171 Dresden (Germany)

    2011-02-15

    A combination of electron backscatter diffraction and energy-dispersive X-ray spectroscopy has been used to identify the crystal structure and composition of all the phases present in commercially available NdFeB sintered magnets and to map their spatial distribution. The Nd{sub 2}Fe{sub 14}B and NdO grains were shown to have low defect densities. The fcc Nd-rich and Nd{sub 2}O{sub 3} grains had intra-grain misorientation angles of up to 14{sup o}, which was shown to be due to defects. Large numbers ({approx}100) of data points for each phase were used to study texture in the NdO, Nd{sub 2}O{sub 3} and Nd{sub 2}Fe{sub 14}B phases. The Nd{sub 2}Fe{sub 14}B grains exhibited a <0 0 1> fibre texture. The Nd oxide phases showed no strong texture, which implied that no strongly preferred orientation relationships between those phases and Nd{sub 2}Fe{sub 14}B exist. The result was shown to be valid for optimally annealed samples exhibiting high coercivity and as-sintered samples exhibiting low coercivity.

  15. Identification of probabilistic approaches and map-based navigation ...

    Indian Academy of Sciences (India)

    B Madhevan

    2018-02-07

    Feb 7, 2018 ... consists of three processes: map learning (ML), localization and PP [73–76]. (i) ML ...... [83] Thrun S 2001 A probabilistic online mapping algorithm for teams of .... for target tracking using fuzzy logic controller in game theoretic ...

  16. Conditional estimation of local pooled dispersion parameter in small-sample RNA-Seq data improves differential expression test.

    Science.gov (United States)

    Gim, Jungsoo; Won, Sungho; Park, Taesung

    2016-10-01

    High throughput sequencing technology in transcriptomics studies contribute to the understanding of gene regulation mechanism and its cellular function, but also increases a need for accurate statistical methods to assess quantitative differences between experiments. Many methods have been developed to account for the specifics of count data: non-normality, a dependence of the variance on the mean, and small sample size. Among them, the small number of samples in typical experiments is still a challenge. Here we present a method for differential analysis of count data, using conditional estimation of local pooled dispersion parameters. A comprehensive evaluation of our proposed method in the aspect of differential gene expression analysis using both simulated and real data sets shows that the proposed method is more powerful than other existing methods while controlling the false discovery rates. By introducing conditional estimation of local pooled dispersion parameters, we successfully overcome the limitation of small power and enable a powerful quantitative analysis focused on differential expression test with the small number of samples.

  17. Map updates in a dynamic Voronoi data structure

    DEFF Research Database (Denmark)

    Mioc, Darka; Antón Castro, Francesc/François; Gold, C. M.

    2006-01-01

    In this paper we are using local and sequential map updates in the Voronoi data structure, which allows us to automatically record each event and performed map updates within the system. These map updates are executed through map construction commands that are composed of atomic actions (geometric...... algorithms for addition, deletion, and motion of spatial objects) on the dynamic Voronoi data structure. The formalization of map commands led to the development of a spatial language comprising a set of atomic operations or constructs on spatial primitives (points and lines), powerful enough to define...

  18. Geomagnetism-Aided Indoor Wi-Fi Radio-Map Construction via Smartphone Crowdsourcing.

    Science.gov (United States)

    Li, Wen; Wei, Dongyan; Lai, Qifeng; Li, Xianghong; Yuan, Hong

    2018-05-08

    Wi-Fi radio-map construction is an important phase in indoor fingerprint localization systems. Traditional methods for Wi-Fi radio-map construction have the problems of being time-consuming and labor-intensive. In this paper, an indoor Wi-Fi radio-map construction method is proposed which utilizes crowdsourcing data contributed by smartphone users. We draw indoor pathway map and construct Wi-Fi radio-map without requiring manual site survey, exact floor layout and extra infrastructure support. The key novelty is that it recognizes road segments from crowdsourcing traces by a cluster based on magnetism sequence similarity and constructs an indoor pathway map with Wi-Fi signal strengths annotated on. Through experiments in real world indoor areas, the method is proved to have good performance on magnetism similarity calculation, road segment clustering and pathway map construction. The Wi-Fi radio maps constructed by crowdsourcing data are validated to provide competitive indoor localization accuracy.

  19. Geomagnetism-Aided Indoor Wi-Fi Radio-Map Construction via Smartphone Crowdsourcing

    Directory of Open Access Journals (Sweden)

    Wen Li

    2018-05-01

    Full Text Available Wi-Fi radio-map construction is an important phase in indoor fingerprint localization systems. Traditional methods for Wi-Fi radio-map construction have the problems of being time-consuming and labor-intensive. In this paper, an indoor Wi-Fi radio-map construction method is proposed which utilizes crowdsourcing data contributed by smartphone users. We draw indoor pathway map and construct Wi-Fi radio-map without requiring manual site survey, exact floor layout and extra infrastructure support. The key novelty is that it recognizes road segments from crowdsourcing traces by a cluster based on magnetism sequence similarity and constructs an indoor pathway map with Wi-Fi signal strengths annotated on. Through experiments in real world indoor areas, the method is proved to have good performance on magnetism similarity calculation, road segment clustering and pathway map construction. The Wi-Fi radio maps constructed by crowdsourcing data are validated to provide competitive indoor localization accuracy.

  20. RF-Based Location Using Interpolation Functions to Reduce Fingerprint Mapping

    Science.gov (United States)

    Ezpeleta, Santiago; Claver, José M.; Pérez-Solano, Juan J.; Martí, José V.

    2015-01-01

    Indoor RF-based localization using fingerprint mapping requires an initial training step, which represents a time consuming process. This location methodology needs a database conformed with RSSI (Radio Signal Strength Indicator) measures from the communication transceivers taken at specific locations within the localization area. But, the real world localization environment is dynamic and it is necessary to rebuild the fingerprint database when some environmental changes are made. This paper explores the use of different interpolation functions to complete the fingerprint mapping needed to achieve the sought accuracy, thereby reducing the effort in the training step. Also, different distributions of test maps and reference points have been evaluated, showing the validity of this proposal and necessary trade-offs. Results reported show that the same or similar localization accuracy can be achieved even when only 50% of the initial fingerprint reference points are taken. PMID:26516862

  1. Mapping liquid hazardous waste migration in ground water with electromagnetic terrain conductivity measurement

    International Nuclear Information System (INIS)

    Ketelle, R.H.; Pin, F.G.

    1984-01-01

    Electromagnetic conductivity measurements were used to map apparent ground conductivity in the vicinity of a liquid hazardous waste disposal site. Approximately 600 conductivity measurements were obtained to prepare a conductivity map of the site which includes an area of 12 ha (30 acres). Conductivity measurements in the area correlate with specific conductance measurements of surface and ground water samples. Contouring of the conductivity data located contaminant migration pathways in the subsurface. A complex contaminant plume was defined by the conductivity survey. Conductivity values obtained reflected anisotropic characteristics related to local bedrock structure. Anisotropic characteristics of measurements and the use of different instrument configurations indicated semiquantitatively the depth of the high conductivity zone and the direction of flow. 4 references, 2 figures

  2. SUPPLEMENT: “GOING THE DISTANCE: MAPPING HOST GALAXIES OF LIGO AND VIRGO SOURCES IN THREE DIMENSIONS USING LOCAL COSMOGRAPHY AND TARGETED FOLLOW-UP” (2016, ApJL, 829, L15)

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Leo P.; Cenko, S. Bradley; Gehrels, Neil; Cannizzo, John [Astroparticle Physics Laboratory, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Chen, Hsin-Yu; Holz, Daniel E.; Farr, Ben [Department of Physics, Enrico Fermi Institute, and Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637 (United States); Farr, Will M.; Veitch, John; Berry, Christopher P. L.; Mandel, Ilya [School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT (United Kingdom); Price, Larry R.; Raymond, Vivien [LIGO Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Kasliwal, Mansi M. [Cahill Center for Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Nissanke, Samaya [Institute of Mathematics, Astrophysics and Particle Physics, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Coughlin, Michael [Department of Physics and Astronomy, Harvard University, Cambridge, MA 02138 (United States); Urban, Alex L. [Leonard E. Parker Center for Gravitation, Cosmology, and Astrophysics, University of Wisconsin–Milwaukee, Milwaukee, WI 53201 (United States); Vitale, Salvatore; Mohapatra, Satya [LIGO Laboratory, Massachusetts Institute of Technology, 185 Albany Street, Cambridge, MA 02139 (United States); Graff, Philip [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2016-09-01

    This is a supplement to the Letter of Singer et al., in which we demonstrated a rapid algorithm for obtaining joint 3D estimates of sky location and luminosity distance from observations of binary neutron star mergers with Advanced LIGO and Virgo. We argued that combining the reconstructed volumes with positions and redshifts of possible host galaxies can provide large-aperture but small field of view instruments with a manageable list of targets to search for optical or infrared emission. In this Supplement, we document the new HEALPix-based file format for 3D localizations of gravitational-wave transients. We include Python sample code to show the reader how to perform simple manipulations of the 3D sky maps and extract ranked lists of likely host galaxies. Finally, we include mathematical details of the rapid volume reconstruction algorithm.

  3. Statistical density modification using local pattern matching

    International Nuclear Information System (INIS)

    Terwilliger, Thomas C.

    2003-01-01

    Statistical density modification can make use of local patterns of density found in protein structures to improve crystallographic phases. A method for improving crystallographic phases is presented that is based on the preferential occurrence of certain local patterns of electron density in macromolecular electron-density maps. The method focuses on the relationship between the value of electron density at a point in the map and the pattern of density surrounding this point. Patterns of density that can be superimposed by rotation about the central point are considered equivalent. Standard templates are created from experimental or model electron-density maps by clustering and averaging local patterns of electron density. The clustering is based on correlation coefficients after rotation to maximize the correlation. Experimental or model maps are also used to create histograms relating the value of electron density at the central point to the correlation coefficient of the density surrounding this point with each member of the set of standard patterns. These histograms are then used to estimate the electron density at each point in a new experimental electron-density map using the pattern of electron density at points surrounding that point and the correlation coefficient of this density to each of the set of standard templates, again after rotation to maximize the correlation. The method is strengthened by excluding any information from the point in question from both the templates and the local pattern of density in the calculation. A function based on the origin of the Patterson function is used to remove information about the electron density at the point in question from nearby electron density. This allows an estimation of the electron density at each point in a map, using only information from other points in the process. The resulting estimates of electron density are shown to have errors that are nearly independent of the errors in the original map using

  4. Maps on large-scale air quality concentrations in the Netherlands. Report on 2009

    International Nuclear Information System (INIS)

    Velders, G.J.M.; Aben, J.M.M.; Blom, W.F.; Diederen, H.S.M.A.; Geilenkirchen, G.P.; Jimmink, B.A.; Koekoek, A.F.; Koelemeijer, R.B.A.; Matthijsen, J.; Peek, C.J.; Van Rijn, F.J.A.; Van Schijndel, M.W.; Van der Sluis, O.C.; De Vries, W.J.

    2009-06-01

    In the Netherlands, the number of locations where the European limit values for particulate matter and nitrogen dioxide concentrations could be exceeded is lower than was estimated last year. The limit value for particulate matter, from 2011 onwards, is possibly be exceeded at only a few locations in the Netherlands, based on standing and proposed national and European policies. These locations are situated mainly in the Randstad area in the Netherlands, in the vicinity of motorways around the large cities, and close to stables in agricultural areas. The limit value for nitrogen dioxide, from 2015 onwards, is possibly to be exceeded along 100 kilometres of roads in cities and along 50 kilometres of motorways. Whether the limit values will actually be exceeded depends also on local policies and meteorological fluctuations. This estimate was based on large-scale concentration maps (called GCN maps) of air quality components, and on additional local contributions. The concentration maps provided the best possible estimate of large-scale air quality. The degree of uncertainty in local concentrations of particulate matter and nitrogen dioxide was estimated to be approximately 15 to 20%. This report presents the methods and emissions used for producing the GCN maps. It also shows the differences with respect to the maps of 2008. These maps are used by local, provincial and other authorities to define additional local measures. PBL would like to emphasise that uncertainties in the concentrations must be kept in mind when using these maps for planning, or when comparing concentrations with limit values. This also applies to the selecting of local measures to improve the air quality. The concentration maps are available online, at http://www. pbl.nl/gcn [nl

  5. Effects of white matter microstructure on phase and susceptibility maps.

    Science.gov (United States)

    Wharton, Samuel; Bowtell, Richard

    2015-03-01

    To investigate the effects on quantitative susceptibility mapping (QSM) and susceptibility tensor imaging (STI) of the frequency variation produced by the microstructure of white matter (WM). The frequency offsets in a WM tissue sample that are not explained by the effect of bulk isotropic or anisotropic magnetic susceptibility, but rather result from the local microstructure, were characterized for the first time. QSM and STI were then applied to simulated frequency maps that were calculated using a digitized whole-brain, WM model formed from anatomical and diffusion tensor imaging data acquired from a volunteer. In this model, the magnitudes of the frequency contributions due to anisotropy and microstructure were derived from the results of the tissue experiments. The simulations suggest that the frequency contribution of microstructure is much larger than that due to bulk effects of anisotropic magnetic susceptibility. In QSM, the microstructure contribution introduced artificial WM heterogeneity. For the STI processing, the microstructure contribution caused the susceptibility anisotropy to be significantly overestimated. Microstructure-related phase offsets in WM yield artifacts in the calculated susceptibility maps. If susceptibility mapping is to become a robust MRI technique, further research should be carried out to reduce the confounding effects of microstructure-related frequency contributions. © 2014 Wiley Periodicals, Inc.

  6. A multicriteria framework for producing local, regional, and national insect and disease risk maps

    Science.gov (United States)

    Frank J. Jr. Krist; Frank J. Sapio

    2010-01-01

    The construction of the 2006 National Insect and Disease Risk Map, compiled by the USDA Forest Service, State and Private Forestry Area, Forest Health Protection Unit, resulted in the development of a GIS-based, multicriteria approach for insect and disease risk mapping that can account for regional variations in forest health concerns and threats. This risk mapping...

  7. Gabor Weber Local Descriptor for Bovine Iris Recognition

    OpenAIRE

    Sun, Shengnan; Zhao, Lindu; Yang, Shicai

    2013-01-01

    Iris recognition is a robust biometric technology. This paper proposes a novel local descriptor for bovine iris recognition, named Gabor Weber local descriptor (GWLD). We first compute the Gabor magnitude maps for the input bovine iris image, and then calculate the differential excitation and orientation for each pixel over each Gabor magnitude map. After that, we use these differential excitations and orientations to construct the GWLD histogram representation. Finally, histogram intersectio...

  8. Theoretical STM maps of curved graphene

    Science.gov (United States)

    Diniz, G. S.; Ulloa, S. E.

    2010-03-01

    We calculate the effect of curvature on the electronic states in monolayer graphene, considering a local ripple along different directions on the plane. The curvature introduces hybridization between σ and π bands and affects the electronic structure and associated wave functions, even opening a gap of the order of few meV at the Dirac point. Our calculation uses a non-orthogonal four-orbital tight-binding representation up to nearest-neighbors, which fully describes the electronic states of the structure. We focus this study on the analysis of theoretical STM maps for different ripple directions and radius of curvature. We discuss the appearance of a well defined pattern in the STM map near the Dirac point, which is strongly modified when the graphene is rippled along different directions, and discuss this effect in terms of a geometric Berry phase. Although it is difficult experimentally to produce and control a well defined direction for the graphene ripple, recent experiments suggest that this structure may be possible in suspended samples with stressors along the edges [1].[4pt] [1] W. Bao et al., Nature Nanotech. 4, 562 (2009).

  9. Characterization of the spatial structure of local functional connectivity using multi-distance average correlation measures.

    Science.gov (United States)

    Macia, Didac; Pujol, Jesus; Blanco-Hinojo, Laura; Martínez-Vilavella, Gerard; Martín-Santos, Rocío; Deus, Joan

    2018-04-24

    There is ample evidence from basic research in neuroscience of the importance of local cortico-cortical networks. Millimetric resolution is achievable with current functional MRI (fMRI) scanners and sequences, and consequently a number of "local" activity similarity measures have been defined to describe patterns of segregation and integration at this spatial scale. We have introduced the use of Iso-Distant local Average Correlation (IDAC), easily defined as the average fMRI temporal correlation of a given voxel with other voxels placed at increasingly separated iso-distant intervals, to characterize the curve of local fMRI signal similarities. IDAC curves can be statistically compared using parametric multivariate statistics. Furthermore, by using RGB color-coding to display jointly IDAC values belonging to three different distance lags, IDAC curves can also be displayed as multi-distance IDAC maps. We applied IDAC analysis to a sample of 41 subjects scanned under two different conditions, a resting state and an auditory-visual continuous stimulation. Multi-distance IDAC mapping was able to discriminate between gross anatomo-functional cortical areas and, moreover, was sensitive to modulation between the two brain conditions in areas known to activate and de-activate during audio-visual tasks. Unlike previous fMRI local similarity measures already in use, our approach draws special attention to the continuous smooth pattern of local functional connectivity.

  10. Using Local Materials To Teach Writing.

    Science.gov (United States)

    Ness, Verna M.

    1997-01-01

    English teachers in foreign countries frequently encounter a lack of materials in English dealing with local topics of interest to students. One suggestion is to use materials written in English for tourists, such as travel brochures or local maps. These materials are readily available in most places at little or no cost from local travel agencies…

  11. A new map of global urban extent from MODIS satellite data

    International Nuclear Information System (INIS)

    Schneider, A; Friedl, M A; Potere, D

    2009-01-01

    Although only a small percentage of global land cover, urban areas significantly alter climate, biogeochemistry, and hydrology at local, regional, and global scales. To understand the impact of urban areas on these processes, high quality, regularly updated information on the urban environment-including maps that monitor location and extent-is essential. Here we present results from efforts to map the global distribution of urban land use at 500 m spatial resolution using remotely sensed data from the Moderate Resolution Imaging Spectroradiometer (MODIS). Our approach uses a supervised decision tree classification algorithm that we process using region-specific parameters. An accuracy assessment based on sites from a stratified random sample of 140 cities shows that the new map has an overall accuracy of 93% (k = 0.65) at the pixel level and a high level of agreement at the city scale (R 2 = 0.90). Our results (available at http://sage.wisc.edu/urbanenvironment.html) also reveal that the land footprint of cities occupies less than 0.5% of the Earth's total land area.

  12. Visualizing fossilization using laser ablation-inductively coupled plasma-mass spectrometry maps of trace elements in Late Cretaceous bones

    Science.gov (United States)

    Koenig, A.E.; Rogers, R.R.; Trueman, C.N.

    2009-01-01

    Elemental maps generated by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) provide a previously unavailable high-resolution visualization of the complex physicochemical conditions operating within individual bones during the early stages of diagenesis and fossilization. A selection of LA-ICP-MS maps of bones collected from the Late Cretaceous of Montana (United States) and Madagascar graphically illustrate diverse paths to recrystallization, and reveal unique insights into geochemical aspects of taphonomic history. Some bones show distinct gradients in concentrations of rare earth elements and uranium, with highest concentrations at external bone margins. Others exhibit more intricate patterns of trace element uptake related to bone histology and its control on the flow paths of pore waters. Patterns of element uptake as revealed by LA-ICP-MS maps can be used to guide sampling strategies, and call into question previous studies that hinge upon localized bulk samples of fossilized bone tissue. LA-ICP-MS maps also allow for comparison of recrystallization rates among fossil bones, and afford a novel approach to identifying bones or regions of bones potentially suitable for extracting intact biogeochemical signals. ?? 2009 Geological Society of America.

  13. Indoor Map Acquisition System Using Global Scan Matching Method and Laser Range Scan Data

    Science.gov (United States)

    Hisanaga, Satoshi; Kase, Takaaki

    Simultaneous localization and mapping (SLAM) is the latest technique for constructing indoor maps. In indoor environment, a localization method using the features of the walls as landmarks has been studied in the past. The past study has a drawback. It cannot localize in spaces surrounded by featureless walls or walls on which similar features are repeated. To overcome this drawback, we developed an accuracy localization method that ignores the features of the walls. We noted the fact that the walls in a building are aligned along only two orthogonal directions. By considering a specific wall to be a reference wall, the location of a robot was expressed by using the distance between the robot and the reference wall. We developed the robot in order to evaluate the mapping accuracy of our method and carried out an experiment to map a corridor (40m long) that contained featureless parts. The map obtained had a margin of error of less than 2%.

  14. Genome-wide SNP association-based localization of a dwarfism gene in Friesian dwarf horses.

    Science.gov (United States)

    Orr, N; Back, W; Gu, J; Leegwater, P; Govindarajan, P; Conroy, J; Ducro, B; Van Arendonk, J A M; MacHugh, D E; Ennis, S; Hill, E W; Brama, P A J

    2010-12-01

    The recent completion of the horse genome and commercial availability of an equine SNP genotyping array has facilitated the mapping of disease genes. We report putative localization of the gene responsible for dwarfism, a trait in Friesian horses that is thought to have a recessive mode of inheritance, to a 2-MB region of chromosome 14 using just 10 affected animals and 10 controls. We successfully genotyped 34,429 SNPs that were tested for association with dwarfism using chi-square tests. The most significant SNP in our study, BIEC2-239376 (P(2df)=4.54 × 10(-5), P(rec)=7.74 × 10(-6)), is located close to a gene implicated in human dwarfism. Fine-mapping and resequencing analyses did not aid in further localization of the causative variant, and replication of our findings in independent sample sets will be necessary to confirm these results. © 2010 The Authors, Journal compilation © 2010 Stichting International Foundation for Animal Genetics.

  15. Recommendations for the user-specific enhancement of flood maps

    Directory of Open Access Journals (Sweden)

    V. Meyer

    2012-05-01

    Full Text Available The European Union Floods Directive requires the establishment of flood maps for high risk areas in all European member states by 2013. However, the current practice of flood mapping in Europe still shows some deficits. Firstly, flood maps are frequently seen as an information tool rather than a communication tool. This means that, for example, local stocks of knowledge are not incorporated. Secondly, the contents of flood maps often do not match the requirements of the end-users. Finally, flood maps are often designed and visualised in a way that cannot be easily understood by residents at risk and/or that is not suitable for the respective needs of public authorities in risk and event management. The RISK MAP project examined how end-user participation in the mapping process may be used to overcome these barriers and enhance the communicative power of flood maps, fundamentally increasing their effectiveness.

    Based on empirical findings from a participatory approach that incorporated interviews, workshops and eye-tracking tests, conducted in five European case studies, this paper outlines recommendations for user-specific enhancements of flood maps. More specific, recommendations are given with regard to (1 appropriate stakeholder participation processes, which allow incorporating local knowledge and preferences, (2 the improvement of the contents of flood maps by considering user-specific needs and (3 the improvement of the visualisation of risk maps in order to produce user-friendly and understandable risk maps for the user groups concerned. Furthermore, "idealised" maps for different user groups are presented: for strategic planning, emergency management and the public.

  16. Photogrammetry and Digital Mapping

    DEFF Research Database (Denmark)

    Frederiksen, Poul

    1998-01-01

    Technical tour to Lithuania, Poland and Estonia for 13 technical staff and managers of State Land Service, HQ, Latvia. Focus on technical aspects and management of geographical data for map production and administration. Visits to state and local government organisations and newly established...

  17. Statistical probabilistic mapping in the individual brain space: decreased metabolism in epilepsy with FDG PET

    International Nuclear Information System (INIS)

    Oh, Jung Su; Lee, Jae Sung; Kim, Yu Kyeong; Chung, June Key; Lee, Myung Chul; Lee, Dong Soo

    2005-01-01

    In the statistical probabilistic mapping, commonly, differences between two or more groups of subjects are statistically analyzed following spatial normalization. However, to our best knowledge, there is few study which performed the statistical mapping in the individual brain space rather than in the stereotaxic brain space, i.e., template space. Therefore, in the current study, a new method for mapping the statistical results in the template space onto individual brain space has been developed. Four young subjects with epilepsy and their age-matched thirty normal healthy subjects were recruited. Both FDG PET and T1 structural MRI was scanned in these groups. Statistical analysis on the decreased FDG metabolism in epilepsy was performed on the SPM with two sample t-test (p < 0.001, intensity threshold 100). To map the statistical results onto individual space, inverse deformation was performed as follows. With SPM deformation toolbox, DCT (discrete cosine transform) basis-encoded deformation fields between individual T1 images and T1 MNI template were obtained. Afterward, inverse of those fields, i.e., inverse deformation fields were obtained. Since both PET and T1 images have been already normalized in the same MNI space, inversely deformed results in PET is on the individual brain MRI space. By applying inverse deformation field on the statistical results of the PET, the statistical map of decreased metabolism in individual spaces were obtained. With statistical results in the template space, localization of decreased metabolism was in the inferior temporal lobe, which was slightly inferior to the hippocampus. The statistical results in the individual space were commonly located in the hippocampus, where the activation should be decreased according to a priori knowledge of neuroscience. With our newly developed statistical mapping on the individual spaces, the localization of the brain functional mapping became more appropriate in the sense of neuroscience

  18. Statistical probabilistic mapping in the individual brain space: decreased metabolism in epilepsy with FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jung Su; Lee, Jae Sung; Kim, Yu Kyeong; Chung, June Key; Lee, Myung Chul; Lee, Dong Soo [Seoul National University Hospital, Seoul (Korea, Republic of)

    2005-07-01

    In the statistical probabilistic mapping, commonly, differences between two or more groups of subjects are statistically analyzed following spatial normalization. However, to our best knowledge, there is few study which performed the statistical mapping in the individual brain space rather than in the stereotaxic brain space, i.e., template space. Therefore, in the current study, a new method for mapping the statistical results in the template space onto individual brain space has been developed. Four young subjects with epilepsy and their age-matched thirty normal healthy subjects were recruited. Both FDG PET and T1 structural MRI was scanned in these groups. Statistical analysis on the decreased FDG metabolism in epilepsy was performed on the SPM with two sample t-test (p < 0.001, intensity threshold 100). To map the statistical results onto individual space, inverse deformation was performed as follows. With SPM deformation toolbox, DCT (discrete cosine transform) basis-encoded deformation fields between individual T1 images and T1 MNI template were obtained. Afterward, inverse of those fields, i.e., inverse deformation fields were obtained. Since both PET and T1 images have been already normalized in the same MNI space, inversely deformed results in PET is on the individual brain MRI space. By applying inverse deformation field on the statistical results of the PET, the statistical map of decreased metabolism in individual spaces were obtained. With statistical results in the template space, localization of decreased metabolism was in the inferior temporal lobe, which was slightly inferior to the hippocampus. The statistical results in the individual space were commonly located in the hippocampus, where the activation should be decreased according to a priori knowledge of neuroscience. With our newly developed statistical mapping on the individual spaces, the localization of the brain functional mapping became more appropriate in the sense of neuroscience.

  19. Gabor Weber Local Descriptor for Bovine Iris Recognition

    Directory of Open Access Journals (Sweden)

    Shengnan Sun

    2013-01-01

    Full Text Available Iris recognition is a robust biometric technology. This paper proposes a novel local descriptor for bovine iris recognition, named Gabor Weber local descriptor (GWLD. We first compute the Gabor magnitude maps for the input bovine iris image, and then calculate the differential excitation and orientation for each pixel over each Gabor magnitude map. After that, we use these differential excitations and orientations to construct the GWLD histogram representation. Finally, histogram intersection is adopted to measure the similarity between different GWLD histograms. The experimental results on the SEU bovine iris database verify the representation power of our proposed local descriptor.

  20. Vaccination with map specific peptides reduces map burden in tissues of infected goats

    DEFF Research Database (Denmark)

    Melvang, Heidi Mikkelsen; Hassan, Sufia Butt; Thakur, Aneesh

    As an alternative to protein-based vaccines, we investigated the effect of post-exposure vaccination with Map specific peptides in a goat model aiming at developing a Map vaccine that will neither interfere with diagnosis of paratuberculosis nor bovine tuberculosis. Peptides were initially select...... in the unvaccinated control group seroconverted in ID Screen® ELISA at last sampling prior to euthanasia. These results indicate that a subunit vaccine against Map can induce a protective immune response against paratuberculosis in goats....

  1. Maps on large-scale air quality concentrations in the Netherlands. Report on 2008

    International Nuclear Information System (INIS)

    Velders, G.J.M.; Aben, J.M.M.; Blom, W.F.; Van Dam, J.D.; Elzenga, H.E.; Geilenkirchen, G.P.; Hammingh, P.; Hoen, A.; Jimmink, B.A.; Koelemeijer, R.B.A.; Matthijsen, J.; Peek, C.J.; Schilderman, C.B.W.; Van der Sluis, O.C.; De Vries, W.J.

    2008-01-01

    Decrease expected in the number of locations exceeding the air quality limit values In the Netherlands, the number of locations were the European limit values for particulate matter and nitrogen dioxide will be exceeded is expected to decrease by 70-90%, in the period up to 2011, respectively 2015. The limit value for particulate matter from 2011 onwards, and for nitrogen dioxide from 2015 onwards, is expected to be exceeded at a small number of locations in the Netherlands, based on standing and proposed Dutch and European policies. These locations are situated mainly in the Randstad, Netherlands, in the vicinity of motorway around the large cities and in the busiest streets in large cities. Whether the limit values will actually be exceeded depends also on local policies and meteorological fluctuations. This estimate is based on large-scale concentration maps (called GCN maps) of air quality components and on additional local contributions. The concentration maps provide the best possible estimate of large-scale air quality. The degree of uncertainty about the local concentrations of particulate matter and nitrogen dioxide is estimated to be approximately 20%. This report presents the methods used to produce the GCN maps and the included emissions. It also shows the differences with respect to the maps of 2007. These maps are used by local, provincial and other authorities. MNP emphasises to keep the uncertainties in the concentrations in mind when using these maps for planning, or when comparing concentrations with limit values. This also applies to the selecting of local measures to improve the air quality. The concentration maps are available online, at http://www.mnp.nl/gcn.html [nl

  2. Electrocorticographic Temporal Alteration Mapping: A Clinical Technique for Mapping the Motor Cortex with Movement-Related Cortical Potentials

    Directory of Open Access Journals (Sweden)

    Zehan Wu

    2017-06-01

    Full Text Available We propose electrocorticographic temporal alteration mapping (ETAM for motor cortex mapping by utilizing movement-related cortical potentials (MRCPs within the low-frequency band [0.05-3] Hz. This MRCP waveform-based temporal domain approach was compared with the state-of-the-art electrocorticographic frequency alteration mapping (EFAM, which is based on frequency spectrum dynamics. Five patients (two epilepsy cases and three tumor cases were enrolled in the study. Each patient underwent intraoperative direct electrocortical stimulation (DECS procedure for motor cortex localization. Moreover, the patients were required to perform simple brisk wrist extension task during awake craniotomy surgery. Cross-validation results showed that the proposed ETAM method had high sensitivity (81.8% and specificity (94.3% in identifying sites which exhibited positive DECS motor responses. Moreover, although the sensitivity of the ETAM and EFAM approaches was not significantly different, ETAM had greater specificity compared with EFAM (94.3 vs. 86.1%. These results indicate that for the intraoperative functional brain mapping, ETAM is a promising novel approach for motor cortex localization with the potential to reduce the need for cortical electrical stimulation.

  3. Forest Biomass Mapping From Lidar and Radar Synergies

    Science.gov (United States)

    Sun, Guoqing; Ranson, K. Jon; Guo, Z.; Zhang, Z.; Montesano, P.; Kimes, D.

    2011-01-01

    The use of lidar and radar instruments to measure forest structure attributes such as height and biomass at global scales is being considered for a future Earth Observation satellite mission, DESDynI (Deformation, Ecosystem Structure, and Dynamics of Ice). Large footprint lidar makes a direct measurement of the heights of scatterers in the illuminated footprint and can yield accurate information about the vertical profile of the canopy within lidar footprint samples. Synthetic Aperture Radar (SAR) is known to sense the canopy volume, especially at longer wavelengths and provides image data. Methods for biomass mapping by a combination of lidar sampling and radar mapping need to be developed. In this study, several issues in this respect were investigated using aircraft borne lidar and SAR data in Howland, Maine, USA. The stepwise regression selected the height indices rh50 and rh75 of the Laser Vegetation Imaging Sensor (LVIS) data for predicting field measured biomass with a R(exp 2) of 0.71 and RMSE of 31.33 Mg/ha. The above-ground biomass map generated from this regression model was considered to represent the true biomass of the area and used as a reference map since no better biomass map exists for the area. Random samples were taken from the biomass map and the correlation between the sampled biomass and co-located SAR signature was studied. The best models were used to extend the biomass from lidar samples into all forested areas in the study area, which mimics a procedure that could be used for the future DESDYnI Mission. It was found that depending on the data types used (quad-pol or dual-pol) the SAR data can predict the lidar biomass samples with R2 of 0.63-0.71, RMSE of 32.0-28.2 Mg/ha up to biomass levels of 200-250 Mg/ha. The mean biomass of the study area calculated from the biomass maps generated by lidar- SAR synergy 63 was within 10% of the reference biomass map derived from LVIS data. The results from this study are preliminary, but do show the

  4. The National Map 2.0 Tactical Plan: "Toward the (Integrated) National Map"

    Science.gov (United States)

    Zulick, Carl A.

    2008-01-01

    The National Map's 2-year goal, as described in this plan, is to provide a range of geospatial products and services that meet the basic goals of the original vision for The National Map while furthering the National Spatial Data Infrastructure that underpins U.S. Geological Survey (USGS) science. To accomplish this goal, the National Geospatial Program (NGP) will acquire, store, maintain, and distribute base map data. The management team for the NGP sets priorities for The National Map in three areas: Data and Products, Services, and Management. Priorities for fiscal years 2008 and 2009 (October 1, 2007 through September 30, 2009), involving the current data inventory, data acquisition, and the integration of data, are (1) incorporating current data from Federal, State, and local organizations into The National Map to the degree possible, given data availability and program resources; (2) collaborating with other USGS programs to incorporate data that support the USGS Science Strategy; (3) supporting the Department of the Interior (DOI) high-priority geospatial information needs; (4) emergency response; (5) homeland security, natural hazards; and (6) graphics products delivery. The management team identified known constraints, enablers, and drivers for the acquisition and integration of data. The NGP management team also identified customer-focused products and services of The National Map. Ongoing planning and management activities direct the development and delivery of these products and services. Management of work flow processes to support The National Map priorities are identified and established through a business-driven prioritization process. This tactical plan is primarily for use as a document to guide The National Map program for the next two fiscal years. The document is available to the public because of widespread interest in The National Map. The USGS collaborates with a broad range of customers and partners who are essential to the success of The

  5. On diagonalization in map(M,G)

    International Nuclear Information System (INIS)

    Blau, M.; Thompson, G.

    1995-01-01

    Motivated by some questions in the path integral approach to (topological) gauge theories, we are led to address the following question: given a smooth map from a manifold M to a compact group G, is it possible to smoothly ''diagonalize'' it, i.e. conjugate it into a map to a maximal torus T of G? We analyze the local and global obstructions and give a complete solution to the problem for regular maps. We establish that these can always be smoothly diagonalized locally and that the obstructions to doing this globally are non-trivial Weyl group and torus bundles on M. We explain the relation of the obstructions to winding numbers of maps into G/T and restrictions of the structure group of a principal G bundle to T and examine the behaviour of gauge fields under this diagonalization. We also discuss the complications that arise in the presence of non-trivial G-bundles and for non-regular maps. We use these results to justify a Weyl integral formula for functional integrals which, as a novel feature not seen in the finite-dimensional case, contains a summation over all those topological T-sectors which arise as restrictions of a trivial principal G bundle and which was used previously to solve completely Yang-Mills theory and the G/ G model in two dimensions. (orig.)

  6. Prevalence of antibiotic resistant Staphylococcus aureus from raw milk samples collected from the local vendors in the region of Tirupathi, India

    Directory of Open Access Journals (Sweden)

    Sudhanthirakodi Sudhanthiramani

    2015-04-01

    Full Text Available Aim: The study was carried out with the aim to identify the suitability of the milk for consumer use with special reference to Staphylococcus aureus from milk samples collected from various local vendors and determine the antibiotic susceptibility pattern of those positive isolates. Materials and Methods: A total of 110 milk samples were collected from the local milk vendors in and around Tirupathi region of India. All the samples were enriched with buffered peptone water in 9:1 ratio and the then inoculated on baird parker agar medium with added 2% egg yolk tellurite emulsion as selective medium for S.aureus and confirmed with mannitol salt agar, Gram’s staining and biochemical tests. The typical cultural characters with coagulase-positive samples were taken as positive samples the positive samples were tested for antibiotic susceptibility with 10 different antibiotics by employing disc diffusion method. Results: Prevalence of coagulase-positive S. aureus was 39.09% (43/110 from the milk samples. The antibiotic susceptibility test of positive isolates showed high resistant toward penicillin G 37/43 (86.04% and ampicillin 32/43 (74.42%, and also showed resistant to methicillin 6/43 (13.95%, cephalothin 6/43 (13.95%, tetracycline 6/43 (13.95%, ciprofloxacin 4/43 (9.30%, enrofloxacin 3/43 (6.97%, cefoxitin 2/43 (4.65%, gentamicin 2/43 (4.65%, and co-trimoxazole 2/43 (4.65%. Many individual isolates showed resistant against two or more antibiotics in our study. Conclusion: The above study results show that the milk samples collected from local vendor having S. aureus, which can induce disease condition as well as antibiotic resistant to the humans particularly young children and old age peoples by means of consumption of raw milk and its products. This is the public health issue, which needs to be solved by educating the local vendors regarding health problems related to unhygienic milk supply and make the awareness among the consumers about this

  7. Mapping geomorphic process domains to predict hillslope sediment size distribution using remotely-sensed data and field sampling, Inyo Creek, California

    Science.gov (United States)

    Leclere, S.; Sklar, L. S.; Genetti, J. R.

    2014-12-01

    The size distribution of sediments produced on hillslopes and supplied to channels depends on the geomorphic processes that weather, detach and transport rock fragments down slopes. Little in the way of theory or data is available to predict patterns in hillslope size distributions at the catchment scale from topographic and geologic maps. Here we use aerial imagery and a variety of remote sensing techniques to map and categorize geomorphic landscape units (GLUs) by inferred sediment production process regime, across the steep mountain catchment of Inyo Creek, eastern Sierra Nevada, California. We also use field measurements of particle size and local geomorphic attributes to test and refine GLU determinations. Across the 2 km of relief in this catchment, landcover varies from bare bedrock cliffs at higher elevations to vegetated, regolith-covered convex slopes at lower elevations. Hillslope gradient could provide a simple index of sediment production process, from rock spallation and landsliding at highest slopes, to tree-throw and other disturbance-driven soil production processes at lowest slopes. However, many other attributes are needed for a more robust predictive model, including elevation, curvature, aspect, drainage area, and color. We combine tools from ArcGIS, ERDAS Imagine and Envi with groundtruthing field work to find an optimal combination of attributes for defining sediment production GLUs. Key challenges include distinguishing: weathered from freshly eroded bedrock, boulders from intact bedrock, and landslide deposits from talus slopes. We take advantage of emerging technologies that provide new ways of conducting fieldwork and comparing field data to mapping solutions. In particular, cellphone GPS is approaching the accuracy of dedicated GPS systems and the ability to geo-reference photos simplifies field notes and increases accuracy of later map creation. However, the predictive power of the GLU mapping approach is limited by inherent uncertainty

  8. Performing Mimetic Mapping: A Non-Visualisable Map of the Suzhou River Area of Shanghai

    Directory of Open Access Journals (Sweden)

    Anastasia Karandinou

    2014-07-01

    Full Text Available This paper questions issues concerning the mapping of experience, through the concept of mimesis – the creative re-performance of the site experience onto the map. The place mapped is the Suzhou River area, a significant part of Shanghai, the former boundary between the British and American Settlements, and an ever-changing and transforming territory. Through the detailed description of the mapping processes, we analyse the position of this particular map within contemporary discourse about mapping. Here, we question the purpose of the process, the desired outcome, the consciousness of the significance of each step/event, and the possible significance of the final traces that the mapping leaves behind. Although after the mapping had been carried out, the procedure was analysed, post-rationalised, and justified through its partial documentation (as part of an educational process, this paper questions the way and the reason for these practices (the post-rationalising of the mapping activity, justifying the strategy, etc., and their possible meaning, purpose, demand or context. Thus we conclude that the subject matter is not the final outcome of an object or ‘map’; there is no final map to be exhibited. What this paper brings forth is the mapping as an event, an action performed by the embodied experience of the actual place and by the trans-local materiality of the tools and elements involved in the process of its making.

  9. cudaMap: a GPU accelerated program for gene expression connectivity mapping.

    Science.gov (United States)

    McArt, Darragh G; Bankhead, Peter; Dunne, Philip D; Salto-Tellez, Manuel; Hamilton, Peter; Zhang, Shu-Dong

    2013-10-11

    Modern cancer research often involves large datasets and the use of sophisticated statistical techniques. Together these add a heavy computational load to the analysis, which is often coupled with issues surrounding data accessibility. Connectivity mapping is an advanced bioinformatic and computational technique dedicated to therapeutics discovery and drug re-purposing around differential gene expression analysis. On a normal desktop PC, it is common for the connectivity mapping task with a single gene signature to take > 2h to complete using sscMap, a popular Java application that runs on standard CPUs (Central Processing Units). Here, we describe new software, cudaMap, which has been implemented using CUDA C/C++ to harness the computational power of NVIDIA GPUs (Graphics Processing Units) to greatly reduce processing times for connectivity mapping. cudaMap can identify candidate therapeutics from the same signature in just over thirty seconds when using an NVIDIA Tesla C2050 GPU. Results from the analysis of multiple gene signatures, which would previously have taken several days, can now be obtained in as little as 10 minutes, greatly facilitating candidate therapeutics discovery with high throughput. We are able to demonstrate dramatic speed differentials between GPU assisted performance and CPU executions as the computational load increases for high accuracy evaluation of statistical significance. Emerging 'omics' technologies are constantly increasing the volume of data and information to be processed in all areas of biomedical research. Embracing the multicore functionality of GPUs represents a major avenue of local accelerated computing. cudaMap will make a strong contribution in the discovery of candidate therapeutics by enabling speedy execution of heavy duty connectivity mapping tasks, which are increasingly required in modern cancer research. cudaMap is open source and can be freely downloaded from http://purl.oclc.org/NET/cudaMap.

  10. GPU-Boosted Camera-Only Indoor Localization

    DEFF Research Database (Denmark)

    Özkil, Ali Gürcan; Fan, Zhun; Kristensen, Jens Klæstrup

    relies on local image features detection, description and matching; by parallelizing these computationally intensive tasks on the graphical processing unit (GPU), it is possible to do online localization using a Topometric Appearance Map. The method is developed as an integral part of a mobile service...

  11. A novel intra-operative, high-resolution atrial mapping approach.

    Science.gov (United States)

    Yaksh, Ameeta; van der Does, Lisette J M E; Kik, Charles; Knops, Paul; Oei, Frans B S; van de Woestijne, Pieter C; Bekkers, Jos A; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S

    2015-12-01

    A new technique is demonstrated for extensive high-resolution intra-operative atrial mapping that will facilitate the localization of atrial fibrillation (AF) sources and identification of the substrate perpetuating AF. Prior to the start of extra-corporal circulation, a 8 × 24-electrode array (2-mm inter-electrode distance) is placed subsequently on all the right and left epicardial atrial sites, including Bachmann's bundle, for recording of unipolar electrograms during sinus rhythm and (induced) AF. AF is induced by high-frequency pacing at the right atrial free wall. A pacemaker wire stitched to the right atrium serves as a reference signal. The indifferent pole is connected to a steal wire fixed to subcutaneous tissue. Electrograms are recorded by a computerized mapping system and, after amplification (gain 1000), filtering (bandwidth 0.5-400 Hz), sampling (1 kHz) and analogue to digital conversion (16 bits), automatically stored on hard disk. During the mapping procedure, real-time visualization secures electrogram quality. Analysis will be performed offline. This technique was performed in 168 patients of 18 years and older, with coronary and/or structural heart disease, with or without AF, electively scheduled for cardiac surgery and a ventricular ejection fraction above 40 %. The mean duration of the entire mapping procedure including preparation time was 9 ± 2 min. Complications related to the mapping procedure during or after cardiac surgery were not observed. We introduce the first epicardial atrial mapping approach with a high resolution of ≥1728 recording sites which can be performed in a procedure time of only 9±2 mins. This mapping technique can potentially identify areas responsible for initiation and persistence of AF and hopefully can individualize both diagnosis and therapy of AF.

  12. Driving Pressure Influence in Voltage Maps Measurement Process Using Advanced Pneumatic Mapping Probe

    Directory of Open Access Journals (Sweden)

    Marek Kukucka

    2016-01-01

    Full Text Available Our paper deals with the method of the voltage-impedance map measurement process as a method useful for the electric mapping of human skin. The area of research extends from the basic research to its practical application in acupuncture skin mapping and acupuncture point localization and visualization. The problem of sufficient skin coverage and electrical contact with measuring electrodes is solved by the conventional mechanical telescopic electrodes and by the pneumatic matrix electrode probe. A 2D or 3D voltage-impedance map of skin is an output of the measuring, interpretation and evaluation process. New pneumatic construction of measuring probe was implemented to achieve a better coverage of specified skin area and get a reduced force range of the touching electrodes allowing the steady contact of the skin-electrode. A skin contact is related to the driving pressure of touching electrodes. Our paper offers experimentally measured results, voltage maps of skin on specific areas, selected measured and described acupuncture points and their applications in electro-acupuncture.

  13. Use of electromagnetic terrain conductivity measurements to map liquid hazardous waste migration in groundwater

    International Nuclear Information System (INIS)

    Ketelle, R.H.; Pin, F.G.

    1983-11-01

    Electromagnetic conductivity measurements have been used to map apparent ground conductivity in the vicinity of a liquid hazardous waste disposal site. An area of approximately 12 ha (30 acres) was surveyed. Approximately 600 conductivity measurements were obtained to prepare a conductivity map of the site. Conductivity measurments in the area correlate with specific conductance measurements of surface and groundwater samples. Contouring of the conductivity data showed the precise location of contaminant migration pathways in the subsurface. A complex contaminant plume was defined by the conductivity survey. Conductivity values obtained reflected anisotropic characteristics related to local bedrock structure. Anisotropy characteristics and the use of different instrument configurations indicated semiquantitatively the depth of the high conductivity zone and the direction of flow

  14. Tapping into local lore: toward scalable local mapping and tagging for rural Africa using mobile devices

    DEFF Research Database (Denmark)

    Jensen, Kasper L; Winschiers-Theophilus, Heike; Rodil, Kasper

    2012-01-01

    In this paper we present a context-aware tool designed for mapping and tagging objects and places of importance to rural communities using sensor-enabled mobile devices. These data sets comprise comprehensive models of specific environments which we use for creating interactive visualized knowled...

  15. A TEM method for analyzing local strain fields in irradiated materials

    International Nuclear Information System (INIS)

    Bennetch, J.I.; Jesser, W.A.

    1983-01-01

    Of great interest to the field of fracture mechanics is the strain field in front of a crack tip. In irradiated materials, cavities which naturally form as a result of radiation provide convenient internal markers. If a miniaturized irradiated tensile sample is pulled in situ in a transmission electron microscope (TEM), both the relative displacement of these cavities and their distortion in shape provide information on localized strain on a microscopic level. In addition, the TEM method allows direct correlation of active slip systems with crack propagation characteristics. To illustrate this method a strain field map was constructed about a crack propagating in a helium irradiated type 316 stainless steel sample containing large cavities. (orig.)

  16. Mapping Patterns of Local Recurrence After Pancreaticoduodenectomy for Pancreatic Adenocarcinoma: A New Approach to Adjuvant Radiation Field Design

    International Nuclear Information System (INIS)

    Dholakia, Avani S.; Kumar, Rachit; Raman, Siva P.; Moore, Joseph A.; Ellsworth, Susannah; McNutt, Todd; Laheru, Daniel A.; Jaffee, Elizabeth; Cameron, John L.; Tran, Phuoc T.; Hobbs, Robert F.; Wolfgang, Christopher L.

    2013-01-01

    Purpose: To generate a map of local recurrences after pancreaticoduodenectomy (PD) for patients with resectable pancreatic ductal adenocarcinoma (PDA) and to model an adjuvant radiation therapy planning treatment volume (PTV) that encompasses a majority of local recurrences. Methods and Materials: Consecutive patients with resectable PDA undergoing PD and 1 or more computed tomography (CT) scans more than 60 days after PD at our institution were reviewed. Patients were divided into 3 groups: no adjuvant treatment (NA), chemotherapy alone (CTA), or chemoradiation (CRT). Cross-sectional scans were centrally reviewed, and local recurrences were plotted to scale with respect to the celiac axis (CA), superior mesenteric artery (SMA), and renal veins on 1 CT scan of a template post-PD patient. An adjuvant clinical treatment volume comprising 90% of local failures based on standard expansions of the CA and SMA was created and simulated on 3 post-PD CT scans to assess the feasibility of this planning approach. Results: Of the 202 patients in the study, 40 (20%), 34 (17%), and 128 (63%) received NA, CTA, and CRT adjuvant therapy, respectively. The rate of margin-positive resections was greater in CRT patients than in CTA patients (28% vs 9%, P=.023). Local recurrence occurred in 90 of the 202 patients overall (45%) and in 19 (48%), 22 (65%), and 49 (38%) in the NA, CTA, and CRT groups, respectively. Ninety percent of recurrences were within a 3.0-cm right-lateral, 2.0-cm left-lateral, 1.5-cm anterior, 1.0-cm posterior, 1.0-cm superior, and 2.0-cm inferior expansion of the combined CA and SMA contours. Three simulated radiation treatment plans using these expansions with adjustments to avoid nearby structures were created to demonstrate the use of this treatment volume. Conclusions: Modified PTVs targeting high-risk areas may improve local control while minimizing toxicities, allowing dose escalation with intensity-modulated or stereotactic body radiation therapy

  17. Mapping Patterns of Local Recurrence After Pancreaticoduodenectomy for Pancreatic Adenocarcinoma: A New Approach to Adjuvant Radiation Field Design

    Energy Technology Data Exchange (ETDEWEB)

    Dholakia, Avani S.; Kumar, Rachit [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Raman, Siva P. [Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Moore, Joseph A.; Ellsworth, Susannah; McNutt, Todd [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Laheru, Daniel A.; Jaffee, Elizabeth [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Cameron, John L. [Department of Surgery, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hobbs, Robert F. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Wolfgang, Christopher L. [Department of Surgery, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); and others

    2013-12-01

    Purpose: To generate a map of local recurrences after pancreaticoduodenectomy (PD) for patients with resectable pancreatic ductal adenocarcinoma (PDA) and to model an adjuvant radiation therapy planning treatment volume (PTV) that encompasses a majority of local recurrences. Methods and Materials: Consecutive patients with resectable PDA undergoing PD and 1 or more computed tomography (CT) scans more than 60 days after PD at our institution were reviewed. Patients were divided into 3 groups: no adjuvant treatment (NA), chemotherapy alone (CTA), or chemoradiation (CRT). Cross-sectional scans were centrally reviewed, and local recurrences were plotted to scale with respect to the celiac axis (CA), superior mesenteric artery (SMA), and renal veins on 1 CT scan of a template post-PD patient. An adjuvant clinical treatment volume comprising 90% of local failures based on standard expansions of the CA and SMA was created and simulated on 3 post-PD CT scans to assess the feasibility of this planning approach. Results: Of the 202 patients in the study, 40 (20%), 34 (17%), and 128 (63%) received NA, CTA, and CRT adjuvant therapy, respectively. The rate of margin-positive resections was greater in CRT patients than in CTA patients (28% vs 9%, P=.023). Local recurrence occurred in 90 of the 202 patients overall (45%) and in 19 (48%), 22 (65%), and 49 (38%) in the NA, CTA, and CRT groups, respectively. Ninety percent of recurrences were within a 3.0-cm right-lateral, 2.0-cm left-lateral, 1.5-cm anterior, 1.0-cm posterior, 1.0-cm superior, and 2.0-cm inferior expansion of the combined CA and SMA contours. Three simulated radiation treatment plans using these expansions with adjustments to avoid nearby structures were created to demonstrate the use of this treatment volume. Conclusions: Modified PTVs targeting high-risk areas may improve local control while minimizing toxicities, allowing dose escalation with intensity-modulated or stereotactic body radiation therapy.

  18. Marine habitat mapping of the Milford Haven Waterway, Wales, UK: Comparison of facies mapping and EUNIS classification for monitoring sediment habitats in an industrialized estuary

    Science.gov (United States)

    Carey, Drew A.; Hayn, Melanie; Germano, Joseph D.; Little, David I.; Bullimore, Blaise

    2015-06-01

    A detailed map and dataset of sedimentary habitats of the Milford Haven Waterway (MHW) was compiled for the Milford Haven Waterway Environmental Surveillance Group (MHWESG) from seafloor images collected in May, 2012 using sediment-profile and plan-view imaging (SPI/PV) survey techniques. This is the most comprehensive synoptic assessment of sediment distribution and benthic habitat composition available for the MHW, with 559 stations covering over 40 km2 of subtidal habitats. In the context of the MHW, an interpretative framework was developed that classified each station within a 'facies' that included information on the location within the waterway and inferred sedimentary and biological processes. The facies approach provides critical information on landscape-scale habitats including relative location and inferred sediment transport processes and can be used to direct future monitoring activities within the MHW and to predict areas of greatest potential risk from contaminant transport. Intertidal sediment 'facies' maps have been compiled in the past for MHW; this approach was expanded to map the subtidal portions of the waterway. Because sediment facies can be projected over larger areas than individual samples (due to assumptions based on physiography, or landforms) they represent an observational model of the distribution of sediments in an estuary. This model can be tested over time and space through comparison with additional past or future sample results. This approach provides a means to evaluate stability or change in the physical and biological conditions of the estuarine system. Initial comparison with past results for intertidal facies mapping and grain size analysis from grab samples showed remarkable stability over time for the MHW. The results of the SPI/PV mapping effort were cross-walked to the European Nature Information System (EUNIS) classification to provide a comparison of locally derived habitat mapping with European-standard habitat

  19. Automatically Annotated Mapping for Indoor Mobile Robot Applications

    DEFF Research Database (Denmark)

    Özkil, Ali Gürcan; Howard, Thomas J.

    2012-01-01

    This paper presents a new and practical method for mapping and annotating indoor environments for mobile robot use. The method makes use of 2D occupancy grid maps for metric representation, and topology maps to indicate the connectivity of the ‘places-of-interests’ in the environment. Novel use...... localization and mapping in topology space, and fuses camera and robot pose estimations to build an automatically annotated global topo-metric map. It is developed as a framework for a hospital service robot and tested in a real hospital. Experiments show that the method is capable of producing globally...... consistent, automatically annotated hybrid metric-topological maps that is needed by mobile service robots....

  20. mapDIA: Preprocessing and statistical analysis of quantitative proteomics data from data independent acquisition mass spectrometry.

    Science.gov (United States)

    Teo, Guoshou; Kim, Sinae; Tsou, Chih-Chiang; Collins, Ben; Gingras, Anne-Claude; Nesvizhskii, Alexey I; Choi, Hyungwon

    2015-11-03

    Data independent acquisition (DIA) mass spectrometry is an emerging technique that offers more complete detection and quantification of peptides and proteins across multiple samples. DIA allows fragment-level quantification, which can be considered as repeated measurements of the abundance of the corresponding peptides and proteins in the downstream statistical analysis. However, few statistical approaches are available for aggregating these complex fragment-level data into peptide- or protein-level statistical summaries. In this work, we describe a software package, mapDIA, for statistical analysis of differential protein expression using DIA fragment-level intensities. The workflow consists of three major steps: intensity normalization, peptide/fragment selection, and statistical analysis. First, mapDIA offers normalization of fragment-level intensities by total intensity sums as well as a novel alternative normalization by local intensity sums in retention time space. Second, mapDIA removes outlier observations and selects peptides/fragments that preserve the major quantitative patterns across all samples for each protein. Last, using the selected fragments and peptides, mapDIA performs model-based statistical significance analysis of protein-level differential expression between specified groups of samples. Using a comprehensive set of simulation datasets, we show that mapDIA detects differentially expressed proteins with accurate control of the false discovery rates. We also describe the analysis procedure in detail using two recently published DIA datasets generated for 14-3-3β dynamic interaction network and prostate cancer glycoproteome. The software was written in C++ language and the source code is available for free through SourceForge website http://sourceforge.net/projects/mapdia/.This article is part of a Special Issue entitled: Computational Proteomics. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Acoustic Communications Considerations for Collaborative Simultaneous Localization and Mapping

    Science.gov (United States)

    2014-12-01

    Mission Operations (NEEMO) off the coast of Key Largo, Florida, in September 2013. The mission used the REMUS vehicles to map a simulated asteroid ...Simplifications and assumptions about sound propagation in one area of the world may not hold true for another area simply based on physical conditions...rays follows a curvilinear path as previously discussed in Section II.B.3. If , at the point of transmission, we consider the acoustic message to be a

  2. Mapping geogenic radon potential by regression kriging

    Energy Technology Data Exchange (ETDEWEB)

    Pásztor, László [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Szabó, Katalin Zsuzsanna, E-mail: sz_k_zs@yahoo.de [Department of Chemistry, Institute of Environmental Science, Szent István University, Páter Károly u. 1, Gödöllő 2100 (Hungary); Szatmári, Gábor; Laborczi, Annamária [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Horváth, Ákos [Department of Atomic Physics, Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest (Hungary)

    2016-02-15

    Radon ({sup 222}Rn) gas is produced in the radioactive decay chain of uranium ({sup 238}U) which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on the physical and meteorological parameters of the soil and can enter and accumulate in buildings. Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP). Identification of areas with high health risks require spatial modeling, that is, mapping of radon risk. In addition to geology and meteorology, physical soil properties play a significant role in the determination of GRP. In order to compile a reliable GRP map for a model area in Central-Hungary, spatial auxiliary information representing GRP forming environmental factors were taken into account to support the spatial inference of the locally measured GRP values. Since the number of measured sites was limited, efficient spatial prediction methodologies were searched for to construct a reliable map for a larger area. Regression kriging (RK) was applied for the interpolation using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly, the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Overall accuracy of the map was tested by Leave-One-Out Cross-Validation. Furthermore the spatial reliability of the resultant map is also estimated by the calculation of the 90% prediction interval of the local prediction values. The applicability of the applied method as well as that of the map is discussed briefly. - Highlights: • A new method

  3. Mapping geogenic radon potential by regression kriging

    International Nuclear Information System (INIS)

    Pásztor, László; Szabó, Katalin Zsuzsanna; Szatmári, Gábor; Laborczi, Annamária; Horváth, Ákos

    2016-01-01

    Radon ( 222 Rn) gas is produced in the radioactive decay chain of uranium ( 238 U) which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on the physical and meteorological parameters of the soil and can enter and accumulate in buildings. Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP). Identification of areas with high health risks require spatial modeling, that is, mapping of radon risk. In addition to geology and meteorology, physical soil properties play a significant role in the determination of GRP. In order to compile a reliable GRP map for a model area in Central-Hungary, spatial auxiliary information representing GRP forming environmental factors were taken into account to support the spatial inference of the locally measured GRP values. Since the number of measured sites was limited, efficient spatial prediction methodologies were searched for to construct a reliable map for a larger area. Regression kriging (RK) was applied for the interpolation using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly, the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Overall accuracy of the map was tested by Leave-One-Out Cross-Validation. Furthermore the spatial reliability of the resultant map is also estimated by the calculation of the 90% prediction interval of the local prediction values. The applicability of the applied method as well as that of the map is discussed briefly. - Highlights: • A new method, regression

  4. Endpoint Distinctiveness Facilitates Analogical Mapping in Pigeons

    Science.gov (United States)

    Hagmann, Carl Erick; Cook, Robert G.

    2015-01-01

    Analogical thinking necessitates mapping shared relations across two separate domains. We investigated whether pigeons could learn faster with ordinal mapping of relations across two physical dimensions (circle size & choice spatial position) relative to random mapping of these relations. Pigeons were trained to relate six circular samples of different sizes to horizontally positioned choice locations in a six alternative matching-to-sample task. Three pigeons were trained in a mapped condition in which circle size mapped directly onto choice spatial position. Three other pigeons were trained in a random condition in which the relations between size and choice position were arbitrarily assigned. The mapped group showed an advantage over the random group in acquiring this task. In a subsequent second phase, reassignment, relations between the dimensions were ordinally reversed for the mapped group and re-randomized for the random group. There was no difference in how quickly matching accuracy re-emerged in the two groups, although the mapped group eventually performed more accurately. Analyses suggested this mapped advantage was likely due endpoint distinctiveness and the benefits of proximity errors during choice responding rather than a conceptual or relational advantage attributable to the common or ordinal map of the two dimensions. This potential difficulty in mapping relations across dimensions may limit the pigeons’ capacity for more advanced types of analogical reasoning. PMID:25447511

  5. Evaluation of methods to produce an image library for automatic patient model localization for dose mapping during fluoroscopically guided procedures

    Science.gov (United States)

    Kilian-Meneghin, Josh; Xiong, Z.; Rudin, S.; Oines, A.; Bednarek, D. R.

    2017-03-01

    The purpose of this work is to evaluate methods for producing a library of 2D-radiographic images to be correlated to clinical images obtained during a fluoroscopically-guided procedure for automated patient-model localization. The localization algorithm will be used to improve the accuracy of the skin-dose map superimposed on the 3D patient- model of the real-time Dose-Tracking-System (DTS). For the library, 2D images were generated from CT datasets of the SK-150 anthropomorphic phantom using two methods: Schmid's 3D-visualization tool and Plastimatch's digitally-reconstructed-radiograph (DRR) code. Those images, as well as a standard 2D-radiographic image, were correlated to a 2D-fluoroscopic image of a phantom, which represented the clinical-fluoroscopic image, using the Corr2 function in Matlab. The Corr2 function takes two images and outputs the relative correlation between them, which is fed into the localization algorithm. Higher correlation means better alignment of the 3D patient-model with the patient image. In this instance, it was determined that the localization algorithm will succeed when Corr2 returns a correlation of at least 50%. The 3D-visualization tool images returned 55-80% correlation relative to the fluoroscopic-image, which was comparable to the correlation for the radiograph. The DRR images returned 61-90% correlation, again comparable to the radiograph. Both methods prove to be sufficient for the localization algorithm and can be produced quickly; however, the DRR method produces more accurate grey-levels. Using the DRR code, a library at varying angles can be produced for the localization algorithm.

  6. Sparse PDF maps for non-linear multi-resolution image operations

    KAUST Repository

    Hadwiger, Markus

    2012-11-01

    We introduce a new type of multi-resolution image pyramid for high-resolution images called sparse pdf maps (sPDF-maps). Each pyramid level consists of a sparse encoding of continuous probability density functions (pdfs) of pixel neighborhoods in the original image. The encoded pdfs enable the accurate computation of non-linear image operations directly in any pyramid level with proper pre-filtering for anti-aliasing, without accessing higher or lower resolutions. The sparsity of sPDF-maps makes them feasible for gigapixel images, while enabling direct evaluation of a variety of non-linear operators from the same representation. We illustrate this versatility for antialiased color mapping, O(n) local Laplacian filters, smoothed local histogram filters (e.g., median or mode filters), and bilateral filters. © 2012 ACM.

  7. NeuroMap: A spline-based interactive open-source software for spatiotemporal mapping of 2D and 3D MEA data

    Directory of Open Access Journals (Sweden)

    Oussama eAbdoun

    2011-01-01

    Full Text Available A major characteristic of neural networks is the complexity of their organization at various spatial scales, from microscopic local circuits to macroscopic brain-scale areas. Understanding how neural information is processed thus entails the ability to study them at multiple scales simultaneously. This is made possible using microelectrodes array (MEA technology. Indeed, high-density MEAs provide large-scale covering (several mm² of whole neural structures combined with microscopic resolution (about 50µm of unit activity. Yet, current options for spatiotemporal representation of MEA-collected data remain limited. Here we present NeuroMap, a new interactive Matlab-based software for spatiotemporal mapping of MEA data. NeuroMap uses thin plate spline interpolation, which provides several assets with respect to conventional mapping methods used currently. First, any MEA design can be considered, including 2D or 3D, regular or irregular, arrangements of electrodes. Second, spline interpolation allows the estimation of activity across the tissue with local extrema not necessarily at recording sites. Finally, this interpolation approach provides a straightforward analytical estimation of the spatial Laplacian for better current sources localization. In this software, coregistration of 2D MEA data on the anatomy of the neural tissue is made possible by fine matching of anatomical data with electrode positions using rigid deformation based correction of anatomical pictures. Overall, NeuroMap provides substantial material for detailed spatiotemporal analysis of MEA data. The package is distributed under GNU General Public License (GPL and available at http://sites.google.com/site/neuromapsoftware.

  8. NeuroMap: A Spline-Based Interactive Open-Source Software for Spatiotemporal Mapping of 2D and 3D MEA Data.

    Science.gov (United States)

    Abdoun, Oussama; Joucla, Sébastien; Mazzocco, Claire; Yvert, Blaise

    2011-01-01

    A major characteristic of neural networks is the complexity of their organization at various spatial scales, from microscopic local circuits to macroscopic brain-scale areas. Understanding how neural information is processed thus entails the ability to study them at multiple scales simultaneously. This is made possible using microelectrodes array (MEA) technology. Indeed, high-density MEAs provide large-scale coverage (several square millimeters) of whole neural structures combined with microscopic resolution (about 50 μm) of unit activity. Yet, current options for spatiotemporal representation of MEA-collected data remain limited. Here we present NeuroMap, a new interactive Matlab-based software for spatiotemporal mapping of MEA data. NeuroMap uses thin plate spline interpolation, which provides several assets with respect to conventional mapping methods used currently. First, any MEA design can be considered, including 2D or 3D, regular or irregular, arrangements of electrodes. Second, spline interpolation allows the estimation of activity across the tissue with local extrema not necessarily at recording sites. Finally, this interpolation approach provides a straightforward analytical estimation of the spatial Laplacian for better current sources localization. In this software, coregistration of 2D MEA data on the anatomy of the neural tissue is made possible by fine matching of anatomical data with electrode positions using rigid-deformation-based correction of anatomical pictures. Overall, NeuroMap provides substantial material for detailed spatiotemporal analysis of MEA data. The package is distributed under GNU General Public License and available at http://sites.google.com/site/neuromapsoftware.

  9. The peeling process of infinite Boltzmann planar maps

    DEFF Research Database (Denmark)

    Budd, Timothy George

    2016-01-01

    criterion has a very simple interpretation. The finite random planar maps under consideration were recently proved to possess a well-defined local limit known as the infinite Boltzmann planar map (IBPM). Inspired by recent work of Curien and Le Gall, we show that the peeling process on the IBPM can...

  10. Detailed deposition density maps constructed by large-scale soil sampling for gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant accident.

    Science.gov (United States)

    Saito, Kimiaki; Tanihata, Isao; Fujiwara, Mamoru; Saito, Takashi; Shimoura, Susumu; Otsuka, Takaharu; Onda, Yuichi; Hoshi, Masaharu; Ikeuchi, Yoshihiro; Takahashi, Fumiaki; Kinouchi, Nobuyuki; Saegusa, Jun; Seki, Akiyuki; Takemiya, Hiroshi; Shibata, Tokushi

    2015-01-01

    Soil deposition density maps of gamma-ray emitting radioactive nuclides from the Fukushima Dai-ichi Nuclear Power Plant (NPP) accident were constructed on the basis of results from large-scale soil sampling. In total 10,915 soil samples were collected at 2168 locations. Gamma rays emitted from the samples were measured by Ge detectors and analyzed using a reliable unified method. The determined radioactivity was corrected to that of June 14, 2011 by considering the intrinsic decay constant of each nuclide. Finally the deposition maps were created for (134)Cs, (137)Cs, (131)I, (129m)Te and (110m)Ag. The radioactivity ratio of (134)Cs-(137)Cs was almost constant at 0.91 regardless of the locations of soil sampling. The radioactivity ratios of (131)I and (129m)Te-(137)Cs were relatively high in the regions south of the Fukushima NPP site. Effective doses for 50 y after the accident were evaluated for external and inhalation exposures due to the observed radioactive nuclides. The radiation doses from radioactive cesium were found to be much higher than those from the other radioactive nuclides. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Spectral signature selection for mapping unvegetated soils

    Science.gov (United States)

    May, G. A.; Petersen, G. W.

    1975-01-01

    Airborne multispectral scanner data covering the wavelength interval from 0.40-2.60 microns were collected at an altitude of 1000 m above the terrain in southeastern Pennsylvania. Uniform training areas were selected within three sites from this flightline. Soil samples were collected from each site and a procedure developed to allow assignment of scan line and element number from the multispectral scanner data to each sampling location. These soil samples were analyzed on a spectrophotometer and laboratory spectral signatures were derived. After correcting for solar radiation and atmospheric attenuation, the laboratory signatures were compared to the spectral signatures derived from these same soils using multispectral scanner data. Both signatures were used in supervised and unsupervised classification routines. Computer-generated maps using the laboratory and multispectral scanner derived signatures resulted in maps that were similar to maps resulting from field surveys. Approximately 90% agreement was obtained between classification maps produced using multispectral scanner derived signatures and laboratory derived signatures.

  12. Distribution of local critical current along sample length and its relation to overall current in a long Bi2223/Ag superconducting composite tape

    International Nuclear Information System (INIS)

    Ochiai, S; Doko, D; Okuda, H; Oh, S S; Ha, D W

    2006-01-01

    The distribution of the local critical current and the n-value along the sample length and its relation to the overall critical current were studied experimentally and analytically for the bent multifilamentary Bi2223/Ag/Ag-Mg alloy superconducting composite tape. Then, based on the results, it was attempted to simulate on a computer the dependence of the critical current on the sample length. The main results are summarized as follows. The experimentally observed relation of the distributed local critical current and n-value to the overall critical current was described comprehensively with a simple voltage summation model, in which the sample was regarded as a one-dimensional series circuit. The sample length dependence of the critical current was reproduced on the computer by a Monte Carlo simulation incorporating the voltage summation model and the regression analysis results for the local critical current distribution and the relation of the n-value to the critical current

  13. Complete Surface Mapping of ICF Shells

    International Nuclear Information System (INIS)

    Stephens, R.B.; Olson, D.; Huang, H.; Gibson, J.B.

    2004-01-01

    Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. We have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ, φ) surface map for accurate 3-D modeling of a shot

  14. COMPLETE SURFACE MAPPING OF ICF SHELLS

    International Nuclear Information System (INIS)

    STEPHENS, R.B.; OLSON, D.; HUANG, H.; GIBSON, J.B.

    2003-09-01

    OAK-B135 Inertial confinement fusion shells have previously been evaluated on the basis of microscopic examination for local defects and limited surface profiling to represent their average fluctuation power. Since defects are local, and don't always have visible edges, this approach both misses some important fluctuations and doesn't properly represent the spatially dependent surface fluctuation power. they have taken the first step toward correcting this problem by demonstrating the capability to completely map the surface of a NIF shell with the resolution to account for all modes. This allows complete accounting of all the surface fluctuations. In the future this capability could be used for valuable shells to generate a complete r(θ,ψ) surface map for accurate 3-D modeling of a shot

  15. SDSS-IV MaNGA: faint quenched galaxies - I. Sample selection and evidence for environmental quenching

    Science.gov (United States)

    Penny, Samantha J.; Masters, Karen L.; Weijmans, Anne-Marie; Westfall, Kyle B.; Bershady, Matthew A.; Bundy, Kevin; Drory, Niv; Falcón-Barroso, Jesús; Law, David; Nichol, Robert C.; Thomas, Daniel; Bizyaev, Dmitry; Brownstein, Joel R.; Freischlad, Gordon; Gaulme, Patrick; Grabowski, Katie; Kinemuchi, Karen; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Daniel; Roman-Lopes, Alexandre; Pan, Kaike; Simmons, Audrey; Wake, David A.

    2016-11-01

    Using kinematic maps from the Sloan Digital Sky Survey (SDSS) Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, we reveal that the majority of low-mass quenched galaxies exhibit coherent rotation in their stellar kinematics. Our sample includes all 39 quenched low-mass galaxies observed in the first year of MaNGA. The galaxies are selected with Mr > -19.1, stellar masses 109 M⊙ 1.9. They lie on the size-magnitude and σ-luminosity relations for previously studied dwarf galaxies. Just six (15 ± 5.7 per cent) are found to have rotation speeds ve, rot 5 × 1010 M⊙), supporting the hypothesis that galaxy-galaxy or galaxy-group interactions quench star formation in low-mass galaxies. The local bright galaxy density for our sample is ρproj = 8.2 ± 2.0 Mpc-2, compared to ρproj = 2.1 ± 0.4 Mpc-2 for a star-forming comparison sample, confirming that the quenched low-mass galaxies are preferentially found in higher density environments.

  16. The National Map - Orthoimagery

    Science.gov (United States)

    Mauck, James; Brown, Kim; Carswell, William J.

    2009-01-01

    Orthorectified digital aerial photographs and satellite images of 1-meter (m) pixel resolution or finer make up the orthoimagery component of The National Map. The process of orthorectification removes feature displacements and scale variations caused by terrain relief and sensor geometry. The result is a combination of the image characteristics of an aerial photograph or satellite image and the geometric qualities of a map. These attributes allow users to: *Measure distance *Calculate areas *Determine shapes of features *Calculate directions *Determine accurate coordinates *Determine land cover and use *Perform change detection *Update maps The standard digital orthoimage is a 1-m or finer resolution, natural color or color infra-red product. Most are now produced as GeoTIFFs and accompanied by a Federal Geographic Data Committee (FGDC)-compliant metadata file. The primary source for 1-m data is the National Agriculture Imagery Program (NAIP) leaf-on imagery. The U.S. Geological Survey (USGS) utilizes NAIP imagery as the image layer on its 'Digital- Map' - a new generation of USGS topographic maps (http://nationalmap.gov/digital_map). However, many Federal, State, and local governments and organizations require finer resolutions to meet a myriad of needs. Most of these images are leaf-off, natural-color products at resolutions of 1-foot (ft) or finer.

  17. Assessment Of Accuracies Of Remote-Sensing Maps

    Science.gov (United States)

    Card, Don H.; Strong, Laurence L.

    1992-01-01

    Report describes study of accuracies of classifications of picture elements in map derived by digital processing of Landsat-multispectral-scanner imagery of coastal plain of Arctic National Wildlife Refuge. Accuracies of portions of map analyzed with help of statistical sampling procedure called "stratified plurality sampling", in which all picture elements in given cluster classified in stratum to which plurality of them belong.

  18. Improving snow density estimation for mapping SWE with Lidar snow depth: assessment of uncertainty in modeled density and field sampling strategies in NASA SnowEx

    Science.gov (United States)

    Raleigh, M. S.; Smyth, E.; Small, E. E.

    2017-12-01

    The spatial distribution of snow water equivalent (SWE) is not sufficiently monitored with either remotely sensed or ground-based observations for water resources management. Recent applications of airborne Lidar have yielded basin-wide mapping of SWE when combined with a snow density model. However, in the absence of snow density observations, the uncertainty in these SWE maps is dominated by uncertainty in modeled snow density rather than in Lidar measurement of snow depth. Available observations tend to have a bias in physiographic regime (e.g., flat open areas) and are often insufficient in number to support testing of models across a range of conditions. Thus, there is a need for targeted sampling strategies and controlled model experiments to understand where and why different snow density models diverge. This will enable identification of robust model structures that represent dominant processes controlling snow densification, in support of basin-scale estimation of SWE with remotely-sensed snow depth datasets. The NASA SnowEx mission is a unique opportunity to evaluate sampling strategies of snow density and to quantify and reduce uncertainty in modeled snow density. In this presentation, we present initial field data analyses and modeling results over the Colorado SnowEx domain in the 2016-2017 winter campaign. We detail a framework for spatially mapping the uncertainty in snowpack density, as represented across multiple models. Leveraging the modular SUMMA model, we construct a series of physically-based models to assess systematically the importance of specific process representations to snow density estimates. We will show how models and snow pit observations characterize snow density variations with forest cover in the SnowEx domains. Finally, we will use the spatial maps of density uncertainty to evaluate the selected locations of snow pits, thereby assessing the adequacy of the sampling strategy for targeting uncertainty in modeled snow density.

  19. Improving Flood Risk Maps as a Capacity Building Activity: Fostering Public Participation and Raising Flood Risk Awareness in the German Mulde Region (project RISK MAP)

    Science.gov (United States)

    Luther, J.; Meyer, V.; Kuhlicke, C.; Scheuer, S.; Unnerstall, H.

    2012-04-01

    The EU Floods Directive requires the establishment of flood risk maps for high risk areas in all EU Member States by 2013. However, if existing at all, the current practice of risk mapping still shows some deficits: Risk maps are often seen as an information tool rather than a communication tool. This means that e.g. important local knowledge is not incorporated and forms a contrast to the understanding of capacity building which calls for engaging individuals in the process of learning and adapting to change and for the establishment of a more interactive public administration that learns equally from its actions and from the feedback it receives. Furthermore, the contents of risk maps often do not match the requirements of the end users, so that risk maps are often designed and visualised in a way which cannot be easily understood by laypersons and/or which is not suitable for the respective needs of public authorities in risk and flood event management. The project RISK MAP aimed at improving flood risk maps as a means to foster public participation and raising flood risk awareness. For achieving this aim, RISK MAP (1) developed rules for appropriate stakeholder participation enabling the incorporation of local knowledge and preferences; (2) improved the content of risk maps by considering different risk criteria through the use of a deliberative multicriteria risk mapping tool; and (3) improved the visualisation of risk maps in order to produce user-friendly risk maps by applying the experimental graphic semiology (EGS) method that uses the eye tracking approach. The research was carried out in five European case studies where the status quo of risk mapping and the legal framework was analysed, several stakeholder interviews and workshops were conducted, the visual perception of risk maps was tested and - based on this empirical work - exemplary improved risk maps were produced. The presentation and paper will outline the main findings of the project which

  20. Large-Area, High-Resolution Tree Cover Mapping with Multi-Temporal SPOT5 Imagery, New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    Adrian Fisher

    2016-06-01

    Full Text Available Tree cover maps are used for many purposes, such as vegetation mapping, habitat connectivity and fragmentation studies. Small remnant patches of native vegetation are recognised as ecologically important, yet they are underestimated in remote sensing products derived from Landsat. High spatial resolution sensors are capable of mapping small patches of trees, but their use in large-area mapping has been limited. In this study, multi-temporal Satellite pour l’Observation de la Terre 5 (SPOT5 High Resolution Geometrical data was pan-sharpened to 5 m resolution and used to map tree cover for the Australian state of New South Wales (NSW, an area of over 800,000 km2. Complete coverages of SPOT5 panchromatic and multispectral data over NSW were acquired during four consecutive summers (2008–2011 for a total of 1256 images. After pre-processing, the imagery was used to model foliage projective cover (FPC, a measure of tree canopy density commonly used in Australia. The multi-temporal imagery, FPC models and 26,579 training pixels were used in a binomial logistic regression model to estimate the probability of each pixel containing trees. The probability images were classified into a binary map of tree cover using local thresholds, and then visually edited to reduce errors. The final tree map was then attributed with the mean FPC value from the multi-temporal imagery. Validation of the binary map based on visually assessed high resolution reference imagery revealed an overall accuracy of 88% (±0.51% standard error, while comparison against airborne lidar derived data also resulted in an overall accuracy of 88%. A preliminary assessment of the FPC map by comparing against 76 field measurements showed a very good agreement (r2 = 0.90 with a root mean square error of 8.57%, although this may not be representative due to the opportunistic sampling design. The map represents a regionally consistent and locally relevant record of tree cover for NSW, and

  1. Evaluation of local radiation damage in silicon sensor via charge collection mapping with the Timepix read-out chip

    International Nuclear Information System (INIS)

    Platkevic, M; Jakubek, J; Jakubek, M; Pospisil, S; Zemlicka, J; Havranek, V; Semian, V

    2013-01-01

    Studies of radiation hardness of silicon sensors are standardly performed with single-pad detectors evaluating their global electrical properties. In this work we introduce a technique to visualize and determine the spatial distribution of radiation damage across the area of a semiconductor sensor. The sensor properties such as charge collection efficiency and charge diffusion were evaluated locally at many points of the sensor creating 2D maps. For this purpose we used a silicon sensor bump bonded to the pixelated Timepix read-out chip. This device, operated in Time-over-threshold (TOT) mode, allows for the direct energy measurement in each pixel. Selected regions of the sensor were intentionally damaged by defined doses (up to 10 12 particles/cm 2 ) of energetic protons (of 2.5 and 4 MeV). The extent of the damage was measured in terms of the detector response to the same ions. This procedure was performed either on-line during irradiation or off-line after it. The response of the detector to each single particle was analyzed determining the charge collection efficiency and lateral charge diffusion. We evaluated the changes of these parameters as a function of radiation dose. These features are related to the local properties such as the spatial homogeneity of the sensor. The effect of radiation damage was also independently investigated measuring local changes of signal response to γ, and X rays and alpha particles.

  2. Mapping and defining sources of variability in bioavailable strontium isotope ratios in the Eastern Mediterranean

    Science.gov (United States)

    Hartman, Gideon; Richards, Mike

    2014-02-01

    The relative contributions of bedrock and atmospheric sources to bioavailable strontium (Sr) pools in local soils was studied in Northern Israel and the Golan regions through intensive systematic sampling of modern plants and invertebrates, to produce a map of modern bioavailable strontium isotope ratios (87Sr/86Sr) for regional reconstructions of human and animal mobility patterns. The study investigates sources of variability in bioavailable 87Sr/86Sr ratios, in particular the intra-and inter-site range of variation in plant 87Sr/86Sr ratios, the range of 87Sr/86Sr ratios of plants growing on marine sedimentary versus volcanic geologies, the differences between ligneous and non-ligneous plants with varying growth and water utilization strategies, and the relative contribution of atmospheric Sr sources from different soil and vegetation types and climatic zones. Results indicate predictable variation in 87Sr/86Sr ratios. Inter- and intra-site differences in bioavailable 87Sr/86Sr ratios average of 0.00025, while the range of 87Sr/86Sr ratios measured regionally in plants and invertebrates is 0.7090 in Pleistocene calcareous sandstone and 0.7074 in mid-Pleistocene volcanic pyroclast. The 87Sr/86Sr ratios measured in plants growing on volcanic bedrock show time dependent increases in atmospheric deposition relative to bedrock weathering. The 87Sr/86Sr ratios measured in plants growing on renzina soils depends on precipitation. The spacing between bedrock 87Sr/86Sr ratios and plants is highest in wet conditions and decreases in dry conditions. The 87Sr/86Sr ratios measured in plants growing on terra rossa soils is relatively constant (0.7085) regardless of precipitation. Ligneous plants are typically closer to bedrock 87Sr/86Sr ratios than non-ligneous plants. Since the bioavailable 87Sr/86Sr ratios currently measured in the region reflect a mix of both exogenous and endogenous sources, changes in the relative contribution of exogenous sources can cause variation

  3. Centenary of Brodmann's map--conception and fate.

    Science.gov (United States)

    Zilles, Karl; Amunts, Katrin

    2010-02-01

    Rarely in the history of neuroscience has a single illustration been as influential as the cytoarchitectonic map of the human brain published by Korbinian Brodmann in his monograph from 1909. The map presents the segregation of the cerebral cortex into 43 areas, as visible in cell body-stained histological sections. More importantly, Brodmann provided a comparative neuroanatomical approach and discussed ontogenetic and pathological aspects as well as structural-functional correlations. One hundred years later, a large number of neuroscientists still use Brodmann's map for localizing neuroimaging data obtained in the living human brain.

  4. California State Waters Map Series-Offshore of Point Reyes, California

    Science.gov (United States)

    Watt, Janet T.; Dartnell, Peter; Golden, Nadine E.; Greene, H. Gary; Erdey, Mercedes D.; Cochrane, Guy R.; Johnson, Samuel Y.; Hartwell, Stephen R.; Kvitek, Rikk G.; Manson, Michael W.; Endris, Charles A.; Dieter, Bryan E.; Sliter, Ray W.; Krigsman, Lisa M.; Lowe, Erik; Chinn, John L.; Watt, Janet T.; Cochran, Susan A.

    2015-01-01

    Reyes bar, and Bolinas shelf domains. Sheet 10 is a geologic map that merges onshore geologic mapping (compiled from existing maps by the California Geological Survey) and new offshore geologic mapping that is based on integration of high-resolution bathymetry and backscatter imagery (sheets 1, 2, 3), seafloor-sediment and rock samples (Reid and others, 2006), digital camera and video imagery (sheet 6), and high-resolution seismic-reflection profiles (sheet 8), as well as aerial-photographic interpretation of nearshore areas. The information provided by the map sheets, pamphlet, and data catalog have a broad range of applications. High-resolution bathymetry, acoustic backscatter, ground-truth-surveying imagery, and habitat mapping all contribute to habitat characterization and ecosystem-based management by providing essential data for delineation of marine protected areas and ecosystem restoration. Many of the maps provide high-resolution baselines that will be critical for monitoring environmental change associated with climate change, coastal development, or other forcings. High-resolution bathymetry is a critical component for modeling coastal flooding caused by storms and tsunamis, as well as inundation associated with longer term sea-level rise. Seismic-reflection and bathymetric data help characterize earthquake and tsunami sources, critical for natural-hazard assessments of coastal zones. Information on sediment distribution and thickness is essential to the understanding of local and regional sediment transport, as well as the development of regional sediment-management plans. In addition, siting of any new offshore infrastructure (for example, pipelines, cables, or renewable-energy facilities) will depend on high-resolution mapping. Finally, this mapping will both stimulate and enable new scientific research and also raise public awareness of, and education about, coastal environments and issues.

  5. Epidemiological geomatics in evaluation of mine risk education in Afghanistan: introducing population weighted raster maps

    Directory of Open Access Journals (Sweden)

    Andersson Neil

    2006-01-01

    Full Text Available Abstract Evaluation of mine risk education in Afghanistan used population weighted raster maps as an evaluation tool to assess mine education performance, coverage and costs. A stratified last-stage random cluster sample produced representative data on mine risk and exposure to education. Clusters were weighted by the population they represented, rather than the land area. A "friction surface" hooked the population weight into interpolation of cluster-specific indicators. The resulting population weighted raster contours offer a model of the population effects of landmine risks and risk education. Five indicator levels ordered the evidence from simple description of the population-weighted indicators (level 0, through risk analysis (levels 1–3 to modelling programme investment and local variations (level 4. Using graphic overlay techniques, it was possible to metamorphose the map, portraying the prediction of what might happen over time, based on the causality models developed in the epidemiological analysis. Based on a lattice of local site-specific predictions, each cluster being a small universe, the "average" prediction was immediately interpretable without losing the spatial complexity.

  6. Endpoint distinctiveness facilitates analogical mapping in pigeons.

    Science.gov (United States)

    Hagmann, Carl Erick; Cook, Robert G

    2015-03-01

    Analogical thinking necessitates mapping shared relations across two separate domains. We investigated whether pigeons could learn faster with ordinal mapping of relations across two physical dimensions (circle size & choice spatial position) relative to random mapping of these relations. Pigeons were trained to relate six circular samples of different sizes to horizontally positioned choice locations in a six alternative matching-to-sample task. Three pigeons were trained in a mapped condition in which circle size mapped directly onto choice spatial position. Three other pigeons were trained in a random condition in which the relations between size and choice position were arbitrarily assigned. The mapped group showed an advantage over the random group in acquiring this task. In a subsequent second phase, relations between the dimensions were ordinally reversed for the mapped group and re-randomized for the random group. There was no difference in how quickly matching accuracy re-emerged in the two groups, although the mapped group eventually performed more accurately. Analyses suggested this mapped advantage was likely due to endpoint distinctiveness and the benefits of proximity errors during choice responding rather than a conceptual or relational advantage attributable to the common or ordinal mapping of the two dimensions. This potential difficulty in mapping relations across dimensions may limit the pigeons' capacity for more advanced types of analogical reasoning. This article is part of a Special Issue entitled: Tribute to Tom Zentall. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Sentinel lymph node biopsy in local recurrence of cutaneous melanoma

    International Nuclear Information System (INIS)

    Junqueira, G. Jr.; Bodanese, B.; Boff, M.F.; Espindola, M.B.; Haack, R.L.; Frigeri, C.D.L.

    2004-01-01

    Full text: Locally recurrent disease in patients with melanoma is usually defined as cutaneous or subcutaneous arising within 5 cm of the primary site after complete excision of the primary lesion. It may represent residual disease not excised with the primary tumor or the outgrowth of the satellite lesions, which are common with melanoma. Lymphatic mapping and sentinel lymph node (SLN) biopsy is highly accurate in staging nodal basins at risk of regional metastases in primary melanoma patients and identifies those who may benefit from earlier lymphadenectomy. Our purpose was to evaluate the efficacy of sentinel lymph node mapping and biopsy in local recurrence of cutaneous melanoma when the primary lesion was less than 1.0mm thick. Three patients with local recurrence of cutaneous melanoma underwent sentinel lymph node mapping and biopsy. All patients underwent preoperative lymphoscintigraphy to identify the lymphatic basin and the site of the sentinel node. All patients subsequently underwent intra-operative lymphatic mapping and selective lymph node biopsy with vital blue dye and hand-held gamma probe. Excised SLN were analysed by conventional histological staining (H and E) and immunohistochemical staining. In all patients the lymphatic mapping and sentinel lymph node biopsy was successful. The SLN biopsy was negative in two patients and positive in one who underwent therapeutic lymph node dissection. Our results indicate that the SLN mapping and biopsy is also possible in patients having local recurrence of cutaneous melanoma. Although long-term results are not available, early results are promising. (author)

  8. Going beyond the flood insurance rate map: insights from flood hazard map co-production

    Science.gov (United States)

    Luke, Adam; Sanders, Brett F.; Goodrich, Kristen A.; Feldman, David L.; Boudreau, Danielle; Eguiarte, Ana; Serrano, Kimberly; Reyes, Abigail; Schubert, Jochen E.; AghaKouchak, Amir; Basolo, Victoria; Matthew, Richard A.

    2018-04-01

    Flood hazard mapping in the United States (US) is deeply tied to the National Flood Insurance Program (NFIP). Consequently, publicly available flood maps provide essential information for insurance purposes, but they do not necessarily provide relevant information for non-insurance aspects of flood risk management (FRM) such as public education and emergency planning. Recent calls for flood hazard maps that support a wider variety of FRM tasks highlight the need to deepen our understanding about the factors that make flood maps useful and understandable for local end users. In this study, social scientists and engineers explore opportunities for improving the utility and relevance of flood hazard maps through the co-production of maps responsive to end users' FRM needs. Specifically, two-dimensional flood modeling produced a set of baseline hazard maps for stakeholders of the Tijuana River valley, US, and Los Laureles Canyon in Tijuana, Mexico. Focus groups with natural resource managers, city planners, emergency managers, academia, non-profit, and community leaders refined the baseline hazard maps by triggering additional modeling scenarios and map revisions. Several important end user preferences emerged, such as (1) legends that frame flood intensity both qualitatively and quantitatively, and (2) flood scenario descriptions that report flood magnitude in terms of rainfall, streamflow, and its relation to an historic event. Regarding desired hazard map content, end users' requests revealed general consistency with mapping needs reported in European studies and guidelines published in Australia. However, requested map content that is not commonly produced included (1) standing water depths following the flood, (2) the erosive potential of flowing water, and (3) pluvial flood hazards, or flooding caused directly by rainfall. We conclude that the relevance and utility of commonly produced flood hazard maps can be most improved by illustrating pluvial flood hazards

  9. Quantitative Architectural Analysis: A New Approach to Cortical Mapping

    Science.gov (United States)

    Schleicher, Axel; Morosan, Patricia; Amunts, Katrin; Zilles, Karl

    2009-01-01

    Results from functional imaging studies are often still interpreted using the classical architectonic brain maps of Brodmann and his successors. One obvious weakness in traditional, architectural mapping is the subjective nature of localizing borders between cortical areas by means of a purely visual, microscopical examination of histological…

  10. Human-Robot Site Survey and Sampling for Space Exploration

    Science.gov (United States)

    Fong, Terrence; Bualat, Maria; Edwards, Laurence; Flueckiger, Lorenzo; Kunz, Clayton; Lee, Susan Y.; Park, Eric; To, Vinh; Utz, Hans; Ackner, Nir

    2006-01-01

    NASA is planning to send humans and robots back to the Moon before 2020. In order for extended missions to be productive, high quality maps of lunar terrain and resources are required. Although orbital images can provide much information, many features (local topography, resources, etc) will have to be characterized directly on the surface. To address this need, we are developing a system to perform site survey and sampling. The system includes multiple robots and humans operating in a variety of team configurations, coordinated via peer-to-peer human-robot interaction. In this paper, we present our system design and describe planned field tests.

  11. Fast, High Resolution, and Wide Modulus Range Nanomechanical Mapping with Bimodal Tapping Mode.

    Science.gov (United States)

    Kocun, Marta; Labuda, Aleksander; Meinhold, Waiman; Revenko, Irène; Proksch, Roger

    2017-10-24

    Tapping mode atomic force microscopy (AFM), also known as amplitude modulated (AM) or AC mode, is a proven, reliable, and gentle imaging mode with widespread applications. Over the several decades that tapping mode has been in use, quantification of tip-sample mechanical properties such as stiffness has remained elusive. Bimodal tapping mode keeps the advantages of single-frequency tapping mode while extending the technique by driving and measuring an additional resonant mode of the cantilever. The simultaneously measured observables of this additional resonance provide the additional information necessary to extract quantitative nanomechanical information about the tip-sample mechanics. Specifically, driving the higher cantilever resonance in a frequency modulated (FM) mode allows direct measurement of the tip-sample interaction stiffness and, with appropriate modeling, the set point-independent local elastic modulus. Here we discuss the advantages of bimodal tapping, coined AM-FM imaging, for modulus mapping. Results are presented for samples over a wide modulus range, from a compliant gel (∼100 MPa) to stiff materials (∼100 GPa), with the same type of cantilever. We also show high-resolution (subnanometer) stiffness mapping of individual molecules in semicrystalline polymers and of DNA in fluid. Combined with the ability to remain quantitative even at line scan rates of nearly 40 Hz, the results demonstrate the versatility of AM-FM imaging for nanomechanical characterization in a wide range of applications.

  12. Detailed gravity survey to help seismic microzonation: Mapping the thickness of unconsolidated deposits in Ottawa, Canada

    Science.gov (United States)

    Lamontagne, M.; Thomas, M.; Silliker, J.; Jobin, D.

    2011-11-01

    In this study, measurements of gravity were made to map and model the thickness of Quaternary deposits (sand and clay) overlying Ordovician limestones in a suburb of Ottawa (Orléans, Ontario). Because ground motion amplification is partly related to the thickness of unconsolidated deposits, this work helps refine the assessment of the earthquake damage potential of the area. It also helps the mapping of clay basins, which can locally exceed 100 m in thickness, where ground motion amplification can occur. Previous work, including well log data and seismic methods, have yielded a wealth of information on near-surface geology in Orléans, thereby providing the necessary constraints to test the applicability of gravity modeling in other locations where other methods cannot always be used. Some 104 gravity stations were occupied in an 8 × 12 km test area in the Orléans. Stations were accurately located with differential GPS that provided centimetric accuracy in elevation. Densities of the unconsolidated Quaternary deposits (Champlain Sea clay) determined on core samples and densities determined on limestone samples from outcrops were used to constrain models of the clay layer overlying the higher density bedrock formations (limestone). The gravity anomaly map delineates areas where clay basins attain > 100 m depth. Assuming a realistic density for the Champlain Sea clays (1.9-2.1 g/cm 3), the thickness over the higher density bedrock formations (Ordovician carbonate rocks) was modeled and compared with well logs and two seismic reflection profiles. The models match quite well with the information determined from well logs and seismic methods. It was found that gravity and the thickness of unconsolidated deposits are correlated but the uncertainties in both data sets preclude the definition of a direct correlation between the two. We propose that gravity measurements at a local scale be used as an inexpensive means of mapping the thickness of unconsolidated deposits

  13. Nonlinear dynamics of the relativistic standard map

    International Nuclear Information System (INIS)

    Nomura, Y.; Ichikawa, Y.H.; Horton, W.

    1991-04-01

    Heating and acceleration of charged particles by RF fields have been extensively investigated by the standard map. The question arises as to how the relativistic effects change the nonlinear dynamical behavior described by the classical standard map. The relativistic standard map is a two parameter (K, Β = ω/kc) family of dynamical systems reducing to the standard map when Β → 0. For Β ≠ 0 the relativistic mass increase suppresses the onset of stochasticity. It shown that the speed of light limits the rate of advance of the phase in the relativistic standard map and introduces KAM surfaces persisting in the high momentum region. An intricate structure of mixing in the higher order periodic orbits and chaotic orbits is analyzed using the symmetry properties of the relativistic standard map. The interchange of the stability of the periodic orbits in the relativistic standard map is also observed and is explained by the local linear stability of the orbits. 12 refs., 16 figs

  14. Singularity theory and equivariant symplectic maps

    CERN Document Server

    Bridges, Thomas J

    1993-01-01

    The monograph is a study of the local bifurcations of multiparameter symplectic maps of arbitrary dimension in the neighborhood of a fixed point.The problem is reduced to a study of critical points of an equivariant gradient bifurcation problem, using the correspondence between orbits ofa symplectic map and critical points of an action functional. New results onsingularity theory for equivariant gradient bifurcation problems are obtained and then used to classify singularities of bifurcating period-q points. Of particular interest is that a general framework for analyzing group-theoretic aspects and singularities of symplectic maps (particularly period-q points) is presented. Topics include: bifurcations when the symplectic map has spatial symmetry and a theory for the collision of multipliers near rational points with and without spatial symmetry. The monograph also includes 11 self-contained appendices each with a basic result on symplectic maps. The monograph will appeal to researchers and graduate student...

  15. 76 FR 60962 - Noise Exposure Map Update for Buffalo Niagara International Airport, Buffalo, NY

    Science.gov (United States)

    2011-09-30

    ... ``2008 Noise Exposure Map with Land Use'' and Figure 9 ``2013 Noise Exposure Map & Affected Land Uses... meet applicable regulations and which depict non-compatible land uses as of the date of submission of... land use control and planning responsibilities of local government. These local responsibilities are...

  16. Nonlinear Spatial Inversion Without Monte Carlo Sampling

    Science.gov (United States)

    Curtis, A.; Nawaz, A.

    2017-12-01

    High-dimensional, nonlinear inverse or inference problems usually have non-unique solutions. The distribution of solutions are described by probability distributions, and these are usually found using Monte Carlo (MC) sampling methods. These take pseudo-random samples of models in parameter space, calculate the probability of each sample given available data and other information, and thus map out high or low probability values of model parameters. However, such methods would converge to the solution only as the number of samples tends to infinity; in practice, MC is found to be slow to converge, convergence is not guaranteed to be achieved in finite time, and detection of convergence requires the use of subjective criteria. We propose a method for Bayesian inversion of categorical variables such as geological facies or rock types in spatial problems, which requires no sampling at all. The method uses a 2-D Hidden Markov Model over a grid of cells, where observations represent localized data constraining the model in each cell. The data in our example application are seismic properties such as P- and S-wave impedances or rock density; our model parameters are the hidden states and represent the geological rock types in each cell. The observations at each location are assumed to depend on the facies at that location only - an assumption referred to as `localized likelihoods'. However, the facies at a location cannot be determined solely by the observation at that location as it also depends on prior information concerning its correlation with the spatial distribution of facies elsewhere. Such prior information is included in the inversion in the form of a training image which represents a conceptual depiction of the distribution of local geologies that might be expected, but other forms of prior information can be used in the method as desired. The method provides direct (pseudo-analytic) estimates of posterior marginal probability distributions over each variable

  17. Evaluating rapid ground sampling and scaling estimated plant cover using UAV imagery up to Landsat for mapping arctic vegetation

    Science.gov (United States)

    Nelson, P.; Paradis, D. P.

    2017-12-01

    The small stature and spectral diversity of arctic plant taxa presents challenges in mapping arctic vegetation. Mapping vegetation at the appropriate scale is needed to visualize effects of disturbance, directional vegetation change or mapping of specific plant groups for other applications (eg. habitat mapping). Fine spatial grain of remotely sensed data (ca. 10 cm pixels) is often necessary to resolve patches of many arctic plant groups, such as bryophytes and lichens. These groups are also spectrally different from mineral, litter and vascular plants. We sought to explore method to generate high-resolution spatial and spectral data to explore better mapping methods for arctic vegetation. We sampled ground vegetation at seven sites north or west of tree-line in Alaska, four north of Fairbanks and three northwest of Bethel, respectively. At each site, we estimated cover of plant functional types in 1m2 quadrats spaced approximately every 10 m along a 100 m long transect. Each quadrat was also scanned using a field spectroradiometer (PSR+ Spectral Evolution, 400-2500 nm range) and photographed from multiple perspectives. We then flew our small UAV with a RGB camera over the transect and at least 50 m on either side collecting on imagery of the plot, which were used to generate a image mosaic and digital surface model of the plot. We compare plant functional group cover ocular estimated in situ to post-hoc estimation, either automated or using a human observer, using the quadrat photos. We also compare interpolated lichen cover from UAV scenes to estimated lichen cover using a statistical models using Landsat data, with focus on lichens. Light and yellow lichens are discernable in the UAV imagery but certain lichens, especially dark colored lichens or those with spectral signatures similar to graminoid litter, present challenges. Future efforts will focus on integrating UAV-upscaled ground cover estimates to hyperspectral sensors (eg. AVIRIS ng) for better combined

  18. Human and Robotic Mission to Small Bodies: Mapping, Planning and Exploration

    Science.gov (United States)

    Neffian, Ara V.; Bellerose, Julie; Beyer, Ross A.; Archinal, Brent; Edwards, Laurence; Lee, Pascal; Colaprete, Anthony; Fong, Terry

    2013-01-01

    This study investigates the requirements, performs a gap analysis and makes a set of recommendations for mapping products and exploration tools required to support operations and scientific discovery for near- term and future NASA missions to small bodies. The mapping products and their requirements are based on the analysis of current mission scenarios (rendezvous, docking, and sample return) and recommendations made by the NEA Users Team (NUT) in the framework of human exploration. The mapping products that sat- isfy operational, scienti c, and public outreach goals include topography, images, albedo, gravity, mass, density, subsurface radar, mineralogical and thermal maps. The gap analysis points to a need for incremental generation of mapping products from low (flyby) to high-resolution data needed for anchoring and docking, real-time spatial data processing for hazard avoidance and astronaut or robot localization in low gravity, high dynamic environments, and motivates a standard for coordinate reference systems capable of describing irregular body shapes. Another aspect investigated in this study is the set of requirements and the gap analysis for exploration tools that support visualization and simulation of operational conditions including soil interactions, environment dynamics, and communications coverage. Building robust, usable data sets and visualisation/simulation tools is the best way for mission designers and simulators to make correct decisions for future missions. In the near term, it is the most useful way to begin building capabilities for small body exploration without needing to commit to specific mission architectures.

  19. Successful Teaching, Learning, and Use of Digital Mapping Technology in Mazvihwa, Rural Zimbabwe

    Science.gov (United States)

    Eitzel Solera, M. V.; Madzoro, S.; Solera, J.; Mhike Hove, E.; Changarara, A.; Ndlovu, D.; Chirindira, A.; Ndlovu, A.; Gwatipedza, S.; Mhizha, M.; Ndlovu, M.

    2016-12-01

    Participatory mapping is now a staple of community-based work around the world. Particularly for indigenous and rural peoples, it can represent a new avenue for environmental justice and can be a tool for culturally appropriate management of local ecosystems. We present a successful example of teaching and learning digital mapping technology in rural Zimbabwe. Our digital mapping project is part of the long-term community-based participatory research of The Muonde Trust in Mazvihwa, Zimbabwe. By gathering and distributing local knowledge and also bringing in visitors to share knowledge, Muonde has been able to spread relevant information among rural farmers. The authors were all members of Muonde or were Muonde's visitors, and were mentors and learners of digital mapping technologies at different times. Key successful characteristics of participants included patience, compassion, openness, perseverance, respect, and humility. Important mentoring strategies included: 1) instruction in Shona and in English, 2) locally relevant examples, assignments, and analogies motivated by real needs, 3) using a variety of teaching methods for different learning modalities, 4) building on and modifying familiar teaching methods, and 5) paying attention to the social and relational aspects of teaching and learning. The Muonde mapping team has used their new skills for a wide variety of purposes, including: identifying, discussing, and acting on emerging needs; using digital mapping for land-use and agropastoral planning; and using mapping as a tool for recording and telling important historical and cultural stories. Digital mapping has built self-confidence as well as providing employable skills and giving Muonde more visibility to other local and national non-governmental organizations, utility companies, and educational institutions. Digital mapping, as taught in a bottom-up, collaborative way, has proven to be both accessible and of enormous practical use to rural Zimbabweans.

  20. Rayleigh-wave phase-velocity maps and three-dimensional shear velocity structure of the western US from local non-plane surface wave tomography

    Science.gov (United States)

    Pollitz, F.F.; Snoke, J. Arthur

    2010-01-01

    We utilize two-and-three-quarter years of vertical-component recordings made by the Transportable Array (TA) component of Earthscope to constrain three-dimensional (3-D) seismic shear wave velocity structure in the upper 200 km of the western United States. Single-taper spectral estimation is used to compile measurements of complex spectral amplitudes from 44 317 seismograms generated by 123 teleseismic events. In the first step employed to determine the Rayleigh-wave phase-velocity structure, we implement a new tomographic method, which is simpler and more robust than scattering-based methods (e.g. multi-plane surface wave tomography). The TA is effectively implemented as a large number of local arrays by defining a horizontal Gaussian smoothing distance that weights observations near a given target point. The complex spectral-amplitude measurements are interpreted with the spherical Helmholtz equation using local observations about a succession of target points, resulting in Rayleigh-wave phase-velocity maps at periods over the range of 18–125 s. The derived maps depend on the form of local fits to the Helmholtz equation, which generally involve the nonplane-wave solutions of Friederich et al. In a second step, the phase-velocity maps are used to derive 3-D shear velocity structure. The 3-D velocity images confirm details witnessed in prior body-wave and surface-wave studies and reveal new structures, including a deep (>100 km deep) high-velocity lineament, of width ∼200 km, stretching from the southern Great Valley to northern Utah that may be a relic of plate subduction or, alternatively, either a remnant of the Mojave Precambrian Province or a mantle downwelling. Mantle seismic velocity is highly correlated with heat flow, Holocene volcanism, elastic plate thickness and seismicity. This suggests that shallow mantle structure provides the heat source for associated magmatism, as well as thinning of the thermal lithosphere, leading to relatively high

  1. Combined Ovarian and Adrenal Venous Sampling in the Localization of Adrenocorticotropic Hormone-Independent Ectopic Cushing Syndrome.

    Science.gov (United States)

    Chen, Shi; Li, Ran; Zhang, Xiaobo; Lu, Lin; Li, Ji; Pan, Hui; Zhu, Huijuan

    2018-03-01

    Cushing syndrome is rarely caused by the secretion of cortisol from ovarian tumors. In clinical decision-making, it is important to determine whether the ovarian tumor is capable of secreting cortisol. Selective ovarian and adrenal venous sampling is scarcely reported in the localization of ACTH-independent ectopic Cushing syndrome. We present a case of 40-year-old Chinese woman who had weight gain, hirsutism, hypertension, and menstrual disorder over 6 months. Her physical examination and biochemical assessment revealed adrenocorticotropic hormone-independent Cushing syndrome. Adrenal computed tomography scan indicated no abnormality. A mass of 5.7 cm × 4.2 cm × 3.4 cm was discovered by pelvic ultrasonography. Somatostatin receptor scintigraphy revealed no abnormal radioactivity intake. Combined ovarian and adrenal venous sampling together with a cortisol assay were conducted. Results revealed cortisol concentration of the right-side ovarian vein, left-side ovarian vein, and peripheral vein of 268.60, 29.00, and 35.18 μg/dL, respectively, suggesting a right-side ovarian origin. A right-side salpingo-oophorectomy was performed and the pathological diagnosis revealed ovarian steroid cell tumor, not otherwise specified. The cortisol level was substantially lower after the patient underwent surgery and symptoms of Cushing syndrome disappeared. At 3-year follow-up, the patient remained disease free, and no tumor was observed on pelvic ultrasonogram. Combined ovarian and adrenal venous sampling is valuable in the localization of adrenocorticotropic hormone-independent ectopic Cushing syndrome.

  2. Physico-empirical approach for mapping soil hydraulic behaviour

    Directory of Open Access Journals (Sweden)

    G. D'Urso

    1997-01-01

    Full Text Available Abstract: Pedo-transfer functions are largely used in soil hydraulic characterisation of large areas. The use of physico-empirical approaches for the derivation of soil hydraulic parameters from disturbed samples data can be greatly enhanced if a characterisation performed on undisturbed cores of the same type of soil is available. In this study, an experimental procedure for deriving maps of soil hydraulic behaviour is discussed with reference to its application in an irrigation district (30 km2 in southern Italy. The main steps of the proposed procedure are: i the precise identification of soil hydraulic functions from undisturbed sampling of main horizons in representative profiles for each soil map unit; ii the determination of pore-size distribution curves from larger disturbed sampling data sets within the same soil map unit. iii the calibration of physical-empirical methods for retrieving soil hydraulic parameters from particle-size data and undisturbed soil sample analysis; iv the definition of functional hydraulic properties from water balance output; and v the delimitation of soil hydraulic map units based on functional properties.

  3. TOWARDS CONSISTENT MAPPING OF URBAN STRUCTURES – GLOBAL HUMAN SETTLEMENT LAYER AND LOCAL CLIMATE ZONES

    Directory of Open Access Journals (Sweden)

    B. Bechtel

    2016-06-01

    Full Text Available Although more than half of the Earth’s population live in urban areas, we know remarkably little about most cities and what we do know is incomplete (lack of coverage and inconsistent (varying definitions and scale. While there have been considerable advances in the derivation of a global urban mask using satellite information, the complexity of urban structures, the heterogeneity of materials, and the multiplicity of spectral properties have impeded the derivation of universal urban structural types (UST. Further, the variety of UST typologies severely limits the comparability of such studies and although a common and generic description of urban structures is an essential requirement for the universal mapping of urban structures, such a standard scheme is still lacking. More recently, there have been two developments in urban mapping that have the potential for providing a standard approach: the Local Climate Zone (LCZ scheme (used by the World Urban Database and Access Portal Tools project and the Global Human Settlement Layer (GHSL methodology by JRC. In this paper the LCZ scheme and the GHSL LABEL product were compared for selected cities. The comparison between both datasets revealed a good agreement at city and coarse scale, while the contingency at pixel scale was limited due to the mismatch in grid resolution and typology. At a 1 km scale, built-up as well as open and compact classes showed very good agreement in terms of correlation coefficient and mean absolute distance, spatial pattern, and radial distribution as a function of distance from town, which indicates that a decomposition relevant for modelling applications could be derived from both. On the other hand, specific problems were found for both datasets, which are discussed along with their general advantages and disadvantages as a standard for UST classification in urban remote sensing.

  4. Marker-Based Multi-Sensor Fusion Indoor Localization System for Micro Air Vehicles.

    Science.gov (United States)

    Xing, Boyang; Zhu, Quanmin; Pan, Feng; Feng, Xiaoxue

    2018-05-25

    A novel multi-sensor fusion indoor localization algorithm based on ArUco marker is designed in this paper. The proposed ArUco mapping algorithm can build and correct the map of markers online with Grubbs criterion and K-mean clustering, which avoids the map distortion due to lack of correction. Based on the conception of multi-sensor information fusion, the federated Kalman filter is utilized to synthesize the multi-source information from markers, optical flow, ultrasonic and the inertial sensor, which can obtain a continuous localization result and effectively reduce the position drift due to the long-term loss of markers in pure marker localization. The proposed algorithm can be easily implemented in a hardware of one Raspberry Pi Zero and two STM32 micro controllers produced by STMicroelectronics (Geneva, Switzerland). Thus, a small-size and low-cost marker-based localization system is presented. The experimental results show that the speed estimation result of the proposed system is better than Px4flow, and it has the centimeter accuracy of mapping and positioning. The presented system not only gives satisfying localization precision, but also has the potential to expand other sensors (such as visual odometry, ultra wideband (UWB) beacon and lidar) to further improve the localization performance. The proposed system can be reliably employed in Micro Aerial Vehicle (MAV) visual localization and robotics control.

  5. Marker-Based Multi-Sensor Fusion Indoor Localization System for Micro Air Vehicles

    Directory of Open Access Journals (Sweden)

    Boyang Xing

    2018-05-01

    Full Text Available A novel multi-sensor fusion indoor localization algorithm based on ArUco marker is designed in this paper. The proposed ArUco mapping algorithm can build and correct the map of markers online with Grubbs criterion and K-mean clustering, which avoids the map distortion due to lack of correction. Based on the conception of multi-sensor information fusion, the federated Kalman filter is utilized to synthesize the multi-source information from markers, optical flow, ultrasonic and the inertial sensor, which can obtain a continuous localization result and effectively reduce the position drift due to the long-term loss of markers in pure marker localization. The proposed algorithm can be easily implemented in a hardware of one Raspberry Pi Zero and two STM32 micro controllers produced by STMicroelectronics (Geneva, Switzerland. Thus, a small-size and low-cost marker-based localization system is presented. The experimental results show that the speed estimation result of the proposed system is better than Px4flow, and it has the centimeter accuracy of mapping and positioning. The presented system not only gives satisfying localization precision, but also has the potential to expand other sensors (such as visual odometry, ultra wideband (UWB beacon and lidar to further improve the localization performance. The proposed system can be reliably employed in Micro Aerial Vehicle (MAV visual localization and robotics control.

  6. Technological Implementation of Renewable Energy in Rural-Isolated Areas and Small-Medium Islands in Indonesia: Problem Mapping And Preliminary Surveys of Total People Participation in a Local Wind Pump Water Supply

    Science.gov (United States)

    Taufik, Ahmad

    2007-10-01

    This article discusses a formulation of problem mapping and preliminary surveys of total people participation in a local wind pump (LWP) water supply in term of technological implementation of renewable energy (RE) in rural-isolated areas and small-medium islands in Indonesia. The formulation was constructed in order to enhance and to promote the local product of RE across Indonesia. It was also addressed to accommodate local potencies, barriers and opportunities into a priority map. Moreover, it was designed into five aspects such as (1) local technology of the RE: a case of pilot project of the LWP; (2) environmental-cultural aspects related to global issues of energy-renewable energy; (3) potencies and barriers corresponding to local, national, regional and international contents; (4) education and training and (5) gender participation. To focus the formulation, serial preliminary surveys were conducted in five major areas, namely: (1) survey on support and barrier factors of the aspects; (2) strategic planning model, a concept A-B-G which stands for Academician-Business people-Government; (3) survey on background based knowledge on energy conservation; (4) survey on gender participation in energy conservation and (5) survey on local stakeholder involvement. Throughout the surveys, it has been notified that the concept needs to be developed to any level of its component since its elements were identified in tolerance values such as high potency value of the LWP development (95%); a strong potency of rural area application (88%); a medium background of energy, energy conservation (EC) identified in a range of 56%-72%, sufficient support from local stakeholders and gender participation.

  7. Bodily maps of emotions.

    Science.gov (United States)

    Nummenmaa, Lauri; Glerean, Enrico; Hari, Riitta; Hietanen, Jari K

    2014-01-14

    Emotions are often felt in the body, and somatosensory feedback has been proposed to trigger conscious emotional experiences. Here we reveal maps of bodily sensations associated with different emotions using a unique topographical self-report method. In five experiments, participants (n = 701) were shown two silhouettes of bodies alongside emotional words, stories, movies, or facial expressions. They were asked to color the bodily regions whose activity they felt increasing or decreasing while viewing each stimulus. Different emotions were consistently associated with statistically separable bodily sensation maps across experiments. These maps were concordant across West European and East Asian samples. Statistical classifiers distinguished emotion-specific activation maps accurately, confirming independence of topographies across emotions. We propose that emotions are represented in the somatosensory system as culturally universal categorical somatotopic maps. Perception of these emotion-triggered bodily changes may play a key role in generating consciously felt emotions.

  8. Landmarks selection in street map design

    International Nuclear Information System (INIS)

    Kao, C J

    2014-01-01

    In Taiwan many electrical maps present their landmarks according to the category of the feature, a designer short of knowledge about mental representation of space, can cause the map to lose its communication effects. To resolve this map design problem, in this research through long-term memory recall, navigation and observation, and short-term memory processing 111 participants were asked to select the proper landmark from study area. The results reveal that in Taiwan convenience stores are the most popular local landmark in rural and urban areas. Their commercial signs have a unique design and bright color. Contrasted to their background, this makes the convenience store a salient feature. This study also developed a rule to assess the priority of the landmarks to design them in different scale maps

  9. Landmarks selection in street map design

    Science.gov (United States)

    Kao, C. J.

    2014-02-01

    In Taiwan many electrical maps present their landmarks according to the category of the feature, a designer short of knowledge about mental representation of space, can cause the map to lose its communication effects. To resolve this map design problem, in this research through long-term memory recall, navigation and observation, and short-term memory processing 111 participants were asked to select the proper landmark from study area. The results reveal that in Taiwan convenience stores are the most popular local landmark in rural and urban areas. Their commercial signs have a unique design and bright color. Contrasted to their background, this makes the convenience store a salient feature. This study also developed a rule to assess the priority of the landmarks to design them in different scale maps.

  10. The correlation of the results of capacitance mapping and of sheet resistance mapping in semi-insulating 6H-SiC

    International Nuclear Information System (INIS)

    Lin Shenghuang; Chen Zhiming; Liang Peng; Jiang Dong; Xie Huajie; Yang Ying

    2010-01-01

    A combination of complex surface capacitance mapping and sheet resistance mapping is applied to establish the origin of resistance variations on semi-insulating (SI) 6H-SiC substrates. The direct correlation between the capacitance quadrature and the sheet resistance is found in vanadium-doped SI samples. Regions with low capacitance quadrature show high sheet resistance. This indicates, associated with the nonhomogeneity of sheet resistance on the substrate, that the quality of crystallization is not good enough, which also leads to resistivity nonhomogeneity when comparing with different types of deep defects. According to the capacitance mapping, the region with bad crystallization quality has a high radio absorption coefficient. Another correlation is established between the capacitance in-phase and sheet resistance for the vanadium-doped sample. In this sample, the capacitance in-phase map shows not only the surface topography, but also the same distribution trend as the sheet resistance, namely, regions of high capacitance in-phase reveal high sheet resistance.

  11. Achieving Accuracy Requirements for Forest Biomass Mapping: A Data Fusion Method for Estimating Forest Biomass and LiDAR Sampling Error with Spaceborne Data

    Science.gov (United States)

    Montesano, P. M.; Cook, B. D.; Sun, G.; Simard, M.; Zhang, Z.; Nelson, R. F.; Ranson, K. J.; Lutchke, S.; Blair, J. B.

    2012-01-01

    The synergistic use of active and passive remote sensing (i.e., data fusion) demonstrates the ability of spaceborne light detection and ranging (LiDAR), synthetic aperture radar (SAR) and multispectral imagery for achieving the accuracy requirements of a global forest biomass mapping mission. This data fusion approach also provides a means to extend 3D information from discrete spaceborne LiDAR measurements of forest structure across scales much larger than that of the LiDAR footprint. For estimating biomass, these measurements mix a number of errors including those associated with LiDAR footprint sampling over regional - global extents. A general framework for mapping above ground live forest biomass (AGB) with a data fusion approach is presented and verified using data from NASA field campaigns near Howland, ME, USA, to assess AGB and LiDAR sampling errors across a regionally representative landscape. We combined SAR and Landsat-derived optical (passive optical) image data to identify forest patches, and used image and simulated spaceborne LiDAR data to compute AGB and estimate LiDAR sampling error for forest patches and 100m, 250m, 500m, and 1km grid cells. Forest patches were delineated with Landsat-derived data and airborne SAR imagery, and simulated spaceborne LiDAR (SSL) data were derived from orbit and cloud cover simulations and airborne data from NASA's Laser Vegetation Imaging Sensor (L VIS). At both the patch and grid scales, we evaluated differences in AGB estimation and sampling error from the combined use of LiDAR with both SAR and passive optical and with either SAR or passive optical alone. This data fusion approach demonstrates that incorporating forest patches into the AGB mapping framework can provide sub-grid forest information for coarser grid-level AGB reporting, and that combining simulated spaceborne LiDAR with SAR and passive optical data are most useful for estimating AGB when measurements from LiDAR are limited because they minimized

  12. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps......, to location-based social networks and games, such as Foursquare and facebook. Warns of the threats these technologies, such as data surveillance, present to our sense of privacy, while also outlining the opportunities for pro-social developments. Provides a theory of the web in the context of the history...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  13. Mapping Local Cytosolic Enzymatic Activity in Human Esophageal Mucosa with Porous Silicon Nanoneedles.

    Science.gov (United States)

    Chiappini, Ciro; Campagnolo, Paola; Almeida, Carina S; Abbassi-Ghadi, Nima; Chow, Lesley W; Hanna, George B; Stevens, Molly M

    2015-09-16

    Porous silicon nanoneedles can map Cathepsin B activity across normal and tumor human esophageal mucosa. Assembling a peptide-based Cathepsin B cleavable sensor over a large array of nano-needles allows the discrimination of cancer cells from healthy ones in mixed culture. The same sensor applied to tissue can map Cathepsin B activity with high resolution across the tumor margin area of esophageal adenocarcinoma. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Neighborhood size of training data influences soil map disaggregation

    Science.gov (United States)

    Soil class mapping relies on the ability of sample locations to represent portions of the landscape with similar soil types; however, most digital soil mapping (DSM) approaches intersect sample locations with one raster pixel per covariate layer regardless of pixel size. This approach does not take ...

  15. Development of a Florida Coastal Mapping Program Through Local and Regional Coordination

    Science.gov (United States)

    Hapke, C. J.; Kramer, P. A.; Fetherston-Resch, E.; Baumstark, R.

    2017-12-01

    The State of Florida has the longest coastline in the contiguous United States (2,170 km). The coastal zone is heavily populated and contains 1,900 km of sandy beaches that support economically important recreation and tourism. Florida's waters also host important marine mineral resources, unique ecosystems, and the largest number of recreational boats and saltwater fishermen in the country. There is increasing need and demand for high resolution data of the coast and adjacent seafloor for resource and habitat mapping, understanding coastal vulnerability, evaluating performance of restoration projects, and many other coastal and marine spatial planning efforts. The Florida Coastal Mapping Program (FCMP), initiated in 2017 as a regional collaboration between four federal and three state agencies, has goals of establishing the priorities for high resolution seafloor mapping of Florida's coastal environment, and developing a strategy for leveraging funds to support mapping priorities set by stakeholders. We began by creating a comprehensive digital inventory of existing data (collected by government, the private sector, and academia) from 1 kilometer inland to the 200 meter isobath for a statewide geospatial database and gap analysis. Data types include coastal topography, bathymetry, and acoustic data such as sidescan sonar and subbottom profiles. Next, we will develop appropriate proposals and legislative budget requests in response to opportunities to collect priority data in high priority areas. Data collection will be undertaken by a combination of state and federal agencies. The FCMP effort will provide the critical baseline information that is required for characterizing changes to fragile ecosystems, assessing marine resources, and forecasting the impacts on coastal infrastructure and recreational beaches from future storms and sea-level rise.

  16. Going Local to Find Help

    Science.gov (United States)

    ... Cover Story: Traumatic Brain Injury Going Local to Find Help Past Issues / Fall 2008 Table of Contents ... phone numbers, maps and directions, such as To Find Out More: Visit www.ninds.nih.gov/Disorders/ ...

  17. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling.

    Science.gov (United States)

    Aerts, Sam; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-10-01

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information-inside hotspots or in search of them-based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km2. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. Copyright © 2013 Elsevier Inc. All rights

  18. Changes in hydrogen isotope ratios in sequential plumage stages: an implication for the creation of isotope-base maps for tracking migratory birds.

    Science.gov (United States)

    Duxbury, J M; Holroyd, G L; Muehlenbachs, K

    2003-09-01

    Accurate reference maps are important in the use of stable-isotopes to track the movements of migratory birds. Reference maps created by the analysis of samples collected from young at the nest site are more accurate than simply referring to naturally occurring patterns of hydrogen isotope ratios created by precipitation cycles. Ratios of hydrogen isotopes in the nutrients incorporated early in the development of young birds can be derived from endogenous, maternal sources. Base-maps should be created with the analysis of tissue samples from hatchlings after local the isotopic signature of exogenous nutrients is dominant. Migratory species such as Peregrine Falcons are known to use endogenous sources in the creation of their eggs, therefore knowledge of what plumage stage best represents the local hydrogen ratios would assist in the planning of nest visits. We conducted diet manipulation experiments involving Japanese Quail and Peregrine Falcons to determine the plumage stage when hydrogen isotope ratios were indicative of a switch in their food source. The natal down of both the quail and falcons reflected the diet of breeding adult females. The hydrogen isotope ratios of a new food source were dominant in the juvenile down of the young falcons, although a further shift was detected in the final juvenile plumage. The juvenile plumage is grown during weeks 3-4 after hatch on Peregrine Falcons. Nest visits for the purpose of collecting feathers for isotope-base-map creation should be made around 4 weeks after the presumed hatch of the young falcons.

  19. Design of a Multi-layer Lane-Level Map for Vehicle Route Planning

    Directory of Open Access Journals (Sweden)

    Liu Chaoran

    2017-01-01

    Full Text Available With the development of intelligent transportation system, there occurs further demand for high precision localization and route planning, and simultaneously the traditional road-level map fails to meet with this requirement, by which this paper is motivated. In this paper, t he three-layer lane-level map architecture for vehicle path guidance is established, and the mathematical models of road-level layer, intermediate layer and lane-level layer are designed considering efficiency and precision. The geometric model of the lane-level layer of the map is characterized by Cubic Hermite Spline for continuity. A method of generating the lane geometry with fixed and variable control points is proposed, which can effectively ensure the accuracy with limited num ber of control points. In experimental part, a multi-layer map of an intersection is built to validate the map model, and an example of a local map was generated with the lane-level geometry.

  20. The application of GBS markers for extending the dense genetic map of rye (Secale cereale L.) and the localization of the Rfc1 gene restoring male fertility in plants with the C source of sterility-inducing cytoplasm.

    Science.gov (United States)

    Milczarski, Paweł; Hanek, Monika; Tyrka, Mirosław; Stojałowski, Stefan

    2016-11-01

    Genotyping by sequencing (GBS) is an efficient method of genotyping in numerous plant species. One of the crucial steps toward the application of GBS markers in crop improvement is anchoring them on particular chromosomes. In rye (Secale cereale L.), chromosomal localization of GBS markers has not yet been reported. In this paper, the application of GBS markers generated by the DArTseq platform for extending the high-density map of rye is presented. Additionally, their application is used for the localization of the Rfc1 gene that restores male fertility in plants with the C source of sterility-inducing cytoplasm. The total number of markers anchored on the current version of the map is 19,081, of which 18,132 were obtained from the DArTseq platform. Numerous markers co-segregated within the studied mapping population, so, finally, only 3397 unique positions were located on the map of all seven rye chromosomes. The total length of the map is 1593 cM and the average distance between markers is 0.47 cM. In spite of the resolution of the map being not very high, it should be a useful tool for further studies of the Secale cereale genome because of the presence on this map of numerous GBS markers anchored for the first time on rye chromosomes. The Rfc1 gene was located on high-density maps of the long arm of the 4R chromosome obtained for two mapping populations. Genetic maps were composed of DArT, DArTseq, and PCR-based markers. Consistent mapping results were obtained and DArTs tightly linked to the Rfc1 gene were successfully applied for the development of six new PCR-based markers useful in marker-assisted selection.

  1. An Integrated Approach Using Chaotic Map & Sample Value Difference Method for Electrocardiogram Steganography and OFDM Based Secured Patient Information Transmission.

    Science.gov (United States)

    Pandey, Anukul; Saini, Barjinder Singh; Singh, Butta; Sood, Neetu

    2017-10-18

    This paper presents a patient's confidential data hiding scheme in electrocardiogram (ECG) signal and its subsequent wireless transmission. Patient's confidential data is embedded in ECG (called stego-ECG) using chaotic map and the sample value difference approach. The sample value difference approach effectually hides the patient's confidential data in ECG sample pairs at the predefined locations. The chaotic map generates these predefined locations through the use of selective control parameters. Subsequently, the wireless transmission of the stego-ECG is analyzed using the Orthogonal Frequency Division Multiplexing (OFDM) system in a Rayleigh fading scenario for telemedicine applications. Evaluation of proposed method on all 48 records of MIT-BIH arrhythmia ECG database demonstrates that the embedding does not alter the diagnostic features of cover ECG. The secret data imperceptibility in stego-ECG is evident through the statistical and clinical performance measures. Statistical measures comprise of Percentage Root-mean-square Difference (PRD), Peak Signal to Noise Ratio (PSNR), and Kulback-Leibler Divergence (KL-Div), etc. while clinical metrics includes wavelet Energy Based Diagnostic Distortion (WEDD) and Wavelet based Weighted PRD (WWPRD). The various channel Signal-to-Noise Ratio scenarios are simulated for wireless communication of stego-ECG in OFDM system. The proposed method over all the 48 records of MIT-BIH arrhythmia database resulted in average, PRD = 0.26, PSNR = 55.49, KL-Div = 3.34 × 10 -6 , WEDD = 0.02, and WWPRD = 0.10 with secret data size of 21Kb. Further, a comparative analysis of proposed method and recent existing works was also performed. The results clearly, demonstrated the superiority of proposed method.

  2. LARGE-SCALE INDICATIVE MAPPING OF SOIL RUNOFF

    Directory of Open Access Journals (Sweden)

    E. Panidi

    2017-11-01

    Full Text Available In our study we estimate relationships between quantitative parameters of relief, soil runoff regime, and spatial distribution of radioactive pollutants in the soil. The study is conducted on the test arable area located in basin of the upper Oka River (Orel region, Russia. Previously we collected rich amount of soil samples, which make it possible to investigate redistribution of the Chernobyl-origin cesium-137 in soil material and as a consequence the soil runoff magnitude at sampling points. Currently we are describing and discussing the technique applied to large-scale mapping of the soil runoff. The technique is based upon the cesium-137 radioactivity measurement in the different relief structures. Key stages are the allocation of the places for soil sampling points (we used very high resolution space imagery as a supporting data; soil samples collection and analysis; calibration of the mathematical model (using the estimated background value of the cesium-137 radioactivity; and automated compilation of the map (predictive map of the studied territory (digital elevation model is used for this purpose, and cesium-137 radioactivity can be predicted using quantitative parameters of the relief. The maps can be used as a support data for precision agriculture and for recultivation or melioration purposes.

  3. The information published by local governments. The websites of Catalonia’s municipal governments

    Directory of Open Access Journals (Sweden)

    M Corcoy Rius

    2013-07-01

    Full Text Available Introduction. The information issued by government institutions must be complete and intelligible so that citizens are able to exercise their right to participation based on informed decisions and the media professionals can use consider these institutions as reliable sources of information. This article presents the results of the development and application of a method to evaluate the information offered by the websites of the municipal governments of Catalonia in order to encourage policymakers to introduce improvements to these platforms. Methods. The sample of study includes the institutional websites run by the government of 947 municipalities of Catalonia. The evaluation is based on 41 purpose-created indicators. Results. The results have been represented on an online geographical mapping tool, titled Map of Good Practices in Local Public Communication, which offers individual and general results and statistics. Conclusions. The publication of results has quickly led to improvements in the sample of websites under analysis, which has led the research team to apply the same evaluation method to the websites of the municipal governments of other five Spanish autonomous communities.

  4. Self-Localization at Street Intersections.

    Science.gov (United States)

    Fusco, Giovanni; Shen, Huiying; Coughlan, James M

    2014-05-01

    There is growing interest among smartphone users in the ability to determine their precise location in their environment for a variety of applications related to wayfinding, travel and shopping. While GPS provides valuable self-localization estimates, its accuracy is limited to approximately 10 meters in most urban locations. This paper focuses on the self-localization needs of blind or visually impaired travelers, who are faced with the challenge of negotiating street intersections. These travelers need more precise self-localization to help them align themselves properly to crosswalks, signal lights and other features such as walk light pushbuttons. We demonstrate a novel computer vision-based localization approach that is tailored to the street intersection domain. Unlike most work on computer vision-based localization techniques, which typically assume the presence of detailed, high-quality 3D models of urban environments, our technique harnesses the availability of simple, ubiquitous satellite imagery (e.g., Google Maps) to create simple maps of each intersection. Not only does this technique scale naturally to the great majority of street intersections in urban areas, but it has the added advantage of incorporating the specific metric information that blind or visually impaired travelers need, namely, the locations of intersection features such as crosswalks. Key to our approach is the integration of IMU (inertial measurement unit) information with geometric information obtained from image panorama stitchings. Finally, we evaluate the localization performance of our algorithm on a dataset of intersection panoramas, demonstrating the feasibility of our approach.

  5. Local subdifferentials and multivariational inequalities in Banach and Frechet spaces

    Directory of Open Access Journals (Sweden)

    Pavlo O. Kasyanov

    2008-01-01

    Full Text Available Some functional-topological concepts of subdifferential and locally subdifferential maps in Frechet spaces are established. Multivariational inequalities with an operator of the pseudo-monotone type, connected with subdifferential maps, are considered.

  6. a Fast and Flexible Method for Meta-Map Building for Icp Based Slam

    Science.gov (United States)

    Kurian, A.; Morin, K. W.

    2016-06-01

    Recent developments in LiDAR sensors make mobile mapping fast and cost effective. These sensors generate a large amount of data which in turn improves the coverage and details of the map. Due to the limited range of the sensor, one has to collect a series of scans to build the entire map of the environment. If we have good GNSS coverage, building a map is a well addressed problem. But in an indoor environment, we have limited GNSS reception and an inertial solution, if available, can quickly diverge. In such situations, simultaneous localization and mapping (SLAM) is used to generate a navigation solution and map concurrently. SLAM using point clouds possesses a number of computational challenges even with modern hardware due to the shear amount of data. In this paper, we propose two strategies for minimizing the cost of computation and storage when a 3D point cloud is used for navigation and real-time map building. We have used the 3D point cloud generated by Leica Geosystems's Pegasus Backpack which is equipped with Velodyne VLP-16 LiDARs scanners. To improve the speed of the conventional iterative closest point (ICP) algorithm, we propose a point cloud sub-sampling strategy which does not throw away any key features and yet significantly reduces the number of points that needs to be processed and stored. In order to speed up the correspondence finding step, a dual kd-tree and circular buffer architecture is proposed. We have shown that the proposed method can run in real time and has excellent navigation accuracy characteristics.

  7. Sparse PDF maps for non-linear multi-resolution image operations

    KAUST Repository

    Hadwiger, Markus; Sicat, Ronell Barrera; Beyer, Johanna; Krü ger, Jens J.; Mö ller, Torsten

    2012-01-01

    feasible for gigapixel images, while enabling direct evaluation of a variety of non-linear operators from the same representation. We illustrate this versatility for antialiased color mapping, O(n) local Laplacian filters, smoothed local histogram filters

  8. Local and global statistical dynamical properties of chaotic Markov analytic maps and repellers: A coarse grained and spectral perspective

    International Nuclear Information System (INIS)

    MacKernan, Donal; Basios, Vasileios

    2009-01-01

    The statistical properties of chaotic Markov analytic maps and equivalent repellers are investigated through matrix representations of the Frobenius-Perron operator (U). The associated basis sets are constructed using Chebyshev functions and Markov partitions which can be tailored to examine statistical dynamical properties associated with observables having support over local regions or for example, about periodic orbits. The decay properties of corresponding time correlations functions are given by a analytic expression of the spectra of U which is expected to be valid for a much larger class of systems than that studied here. An explicit and general expression is also derived for the correction factor to the dynamical zeta functions occurring when analytic function spaces are not invariant under U.

  9. Telling Anthropocene Tales: Localizing the impacts of global change using data-driven story maps

    Science.gov (United States)

    Mychajliw, A.; Hadly, E. A.

    2016-12-01

    Navigating the Anthropocene requires innovative approaches for generating scientific knowledge and for its communication outside academia. The global, synergistic nature of the environmental challenges we face - climate change, human population growth, biodiversity loss, pollution, invasive species and diseases - highlight the need for public outreach strategies that incorporate multiple scales and perspectives in an easily understandable and rapidly accessible format. Data-driven story-telling maps are optimal in that they can display variable geographic scales and their intersections with the environmental challenges relevant to both scientists and non-scientists. Maps are a powerful way to present complex data to all stakeholders. We present an overview of best practices in community-engaged scientific story-telling and data translation for policy-makers by reviewing three Story Map projects that map the geographic impacts of global change across multiple spatial and policy scales: the entire United States, the state of California, and the town of Pescadero, California. We document a chain of translation from a primary scientific manscript to a policy document (Scientific Consensus Statement on Maintaining Humanity's Life Support Systems in the 21st Century) to a set of interactive ArcGIS Story Maps. We discuss the widening breadth of participants (students, community members) and audiences (White House, Governor's Office of California, California Congressional Offices, general public) involved. We highlight how scientists, through careful curation of popular news media articles and stakeholder interviews, can co-produce these communication modules with community partners such as non-governmental organizations and government agencies. The placement of scientific and citizen's everyday knowledge of global change into an appropriate geographic context allows for effective dissemination by political units such as congressional districts and agency management units

  10. A degree theory for a class of perturbed Fredholm maps II

    Directory of Open Access Journals (Sweden)

    Calamai Alessandro

    2006-01-01

    Full Text Available In a recent paper we gave a notion of degree for a class of perturbations of nonlinear Fredholm maps of index zero between real infinite dimensional Banach spaces. Our purpose here is to extend that notion in order to include the degree introduced by Nussbaum for local -condensing perturbations of the identity, as well as the degree for locally compact perturbations of Fredholm maps of index zero recently defined by the first and third authors.

  11. Biomass energy inventory and mapping system

    Energy Technology Data Exchange (ETDEWEB)

    Kasile, J.D. [Ohio State Univ., Columbus, OH (United States)

    1993-12-31

    A four-stage biomass energy inventory and mapping system was conducted for the entire State of Ohio. The product is a set of maps and an inventory of the State of Ohio. The set of amps and an inventory of the State`s energy biomass resource are to a one kilometer grid square basis on the Universal Transverse Mercator (UTM) system. Each square kilometer is identified and mapped showing total British Thermal Unit (BTU) energy availability. Land cover percentages and BTU values are provided for each of nine biomass strata types for each one kilometer grid square. LANDSAT satellite data was used as the primary stratifier. The second stage sampling was the photointerpretation of randomly selected one kilometer grid squares that exactly corresponded to the LANDSAT one kilometer grid square classification orientation. Field sampling comprised the third stage of the energy biomass inventory system and was combined with the fourth stage sample of laboratory biomass energy analysis using a Bomb calorimeter and was then used to assign BTU values to the photointerpretation and to adjust the LANDSAT classification. The sampling error for the whole system was 3.91%.

  12. Method for Pre-Conditioning a Measured Surface Height Map for Model Validation

    Science.gov (United States)

    Sidick, Erkin

    2012-01-01

    This software allows one to up-sample or down-sample a measured surface map for model validation, not only without introducing any re-sampling errors, but also eliminating the existing measurement noise and measurement errors. Because the re-sampling of a surface map is accomplished based on the analytical expressions of Zernike-polynomials and a power spectral density model, such re-sampling does not introduce any aliasing and interpolation errors as is done by the conventional interpolation and FFT-based (fast-Fourier-transform-based) spatial-filtering method. Also, this new method automatically eliminates the measurement noise and other measurement errors such as artificial discontinuity. The developmental cycle of an optical system, such as a space telescope, includes, but is not limited to, the following two steps: (1) deriving requirements or specs on the optical quality of individual optics before they are fabricated through optical modeling and simulations, and (2) validating the optical model using the measured surface height maps after all optics are fabricated. There are a number of computational issues related to model validation, one of which is the "pre-conditioning" or pre-processing of the measured surface maps before using them in a model validation software tool. This software addresses the following issues: (1) up- or down-sampling a measured surface map to match it with the gridded data format of a model validation tool, and (2) eliminating the surface measurement noise or measurement errors such that the resulted surface height map is continuous or smoothly-varying. So far, the preferred method used for re-sampling a surface map is two-dimensional interpolation. The main problem of this method is that the same pixel can take different values when the method of interpolation is changed among the different methods such as the "nearest," "linear," "cubic," and "spline" fitting in Matlab. The conventional, FFT-based spatial filtering method used to

  13. Laser Scribed Graphene Biosensor for Detection of Biogenic Amines in Food Samples Using Locally Sourced Materials

    Directory of Open Access Journals (Sweden)

    Diana C. Vanegas

    2018-04-01

    Full Text Available In foods, high levels of biogenic amines (BA are the result of microbial metabolism that could be affected by temperatures and storage conditions. Thus, the level of BA is commonly used as an indicator of food safety and quality. This manuscript outlines the development of laser scribed graphene electrodes, with locally sourced materials, for reagent-free food safety biosensing. To fabricate the biosensors, the graphene surface was functionalized with copper microparticles and diamine oxidase, purchased from a local supermarket; and then compared to biosensors fabricated with analytical grade materials. The amperometric biosensor exhibits good electrochemical performance, with an average histamine sensitivity of 23.3 µA/mM, a lower detection limit of 11.6 µM, and a response time of 7.3 s, showing similar performance to biosensors constructed from analytical grade materials. We demonstrated the application of the biosensor by testing total BA concentration in fish paste samples subjected to fermentation with lactic acid bacteria. Biogenic amines concentrations prior to lactic acid fermentation were below the detection limit of the biosensor, while concentration after fermentation was 19.24 ± 8.21 mg histamine/kg, confirming that the sensor was selective in a complex food matrix. The low-cost, rapid, and accurate device is a promising tool for biogenic amine estimation in food samples, particularly in situations where standard laboratory techniques are unavailable, or are cost prohibitive. This biosensor can be used for screening food samples, potentially limiting food waste, while reducing chances of foodborne outbreaks.

  14. Exploring structural variability in X-ray crystallographic models using protein local optimization by torsion-angle sampling

    International Nuclear Information System (INIS)

    Knight, Jennifer L.; Zhou, Zhiyong; Gallicchio, Emilio; Himmel, Daniel M.; Friesner, Richard A.; Arnold, Eddy; Levy, Ronald M.

    2008-01-01

    Torsion-angle sampling, as implemented in the Protein Local Optimization Program (PLOP), is used to generate multiple structurally variable single-conformer models which are in good agreement with X-ray data. An ensemble-refinement approach to differentiate between positional uncertainty and conformational heterogeneity is proposed. Modeling structural variability is critical for understanding protein function and for modeling reliable targets for in silico docking experiments. Because of the time-intensive nature of manual X-ray crystallographic refinement, automated refinement methods that thoroughly explore conformational space are essential for the systematic construction of structurally variable models. Using five proteins spanning resolutions of 1.0–2.8 Å, it is demonstrated how torsion-angle sampling of backbone and side-chain libraries with filtering against both the chemical energy, using a modern effective potential, and the electron density, coupled with minimization of a reciprocal-space X-ray target function, can generate multiple structurally variable models which fit the X-ray data well. Torsion-angle sampling as implemented in the Protein Local Optimization Program (PLOP) has been used in this work. Models with the lowest R free values are obtained when electrostatic and implicit solvation terms are included in the effective potential. HIV-1 protease, calmodulin and SUMO-conjugating enzyme illustrate how variability in the ensemble of structures captures structural variability that is observed across multiple crystal structures and is linked to functional flexibility at hinge regions and binding interfaces. An ensemble-refinement procedure is proposed to differentiate between variability that is a consequence of physical conformational heterogeneity and that which reflects uncertainty in the atomic coordinates

  15. Situations in Construction of 3D Mapping for Slam

    OpenAIRE

    Nguyen Hoang Thuy Trang; Shydlouski Stanislav

    2018-01-01

    Nowadays, the simultaneous localization and mapping (SLAM) approach has become one of the most advanced engineering methods used for mobile robots to build maps in unknown or inaccessible spaces. Update maps before a certain area while tracking current location and distance. The motivation behind writing this paper is mainly to help us better understand about SLAM and the study situation of SLAM in the world today. Through this, we find the optimal algorithm for moving robots in three dimensi...

  16. Carotenoids co-localize with hydroxyapatite, cholesterol, and other lipids in calcified stenotic aortic valves. Ex vivo Raman maps compared to histological patterns

    Directory of Open Access Journals (Sweden)

    A. Bonetti

    2015-04-01

    Full Text Available Unlike its application for atherosclerotic plaque analysis, Raman microspectroscopy was sporadically used to check the sole nature of bioapatite deposits in stenotic aortic valves, neglecting the involvement of accumulated lipids/lipoproteins in the calcific process. Here, Raman microspectroscopy was employed for examination of stenotic aortic valve leaflets to add information on nature and distribution of accumulated lipids and their correlation with mineralization in the light of its potential precocious diagnostic use. Cryosections from surgically explanted stenotic aortic valves (n=4 were studied matching Raman maps against specific histological patterns. Raman maps revealed the presence of phospholipids/triglycerides and cholesterol, which showed spatial overlapping with one another and Raman-identified hydroxyapatite. Moreover, the Raman patterns correlated with those displayed by both von-Kossa-calcium- and Nile-blue-stained serial cryosections. Raman analysis also provided the first identification of carotenoids, which co-localized with the identified lipid moieties. Additional fit concerned the distribution of collagen and elastin. The good correlation of Raman maps with high-affinity staining patterns proved that Raman microspectroscopy is a reliable tool in evaluating calcification degree, alteration/displacement of extracellular matrix components, and accumulation rate of different lipid forms in calcified heart valves. In addition, the novel identification of carotenoids supports the concept that valve stenosis is an atherosclerosis-like valve lesion, consistently with their previous Raman microspectroscopical identification inside atherosclerotic plaques.

  17. Carotenoids co-localize with hydroxyapatite, cholesterol, and other lipids in calcified stenotic aortic valves. Ex vivo Raman maps compared to histological patterns.

    Science.gov (United States)

    Bonetti, A; Bonifacio, A; Della Mora, A; Livi, U; Marchini, M; Ortolani, F

    2015-04-20

    Unlike its application for atherosclerotic plaque analysis, Raman microspectroscopy was sporadically used to check the sole nature of bioapatite deposits in stenotic aortic valves, neglecting the involvement of accumulated lipids/lipoproteins in the calcific process. Here, Raman microspectroscopy was employed for examination of stenotic aortic valve leaflets to add information on nature and distribution of accumulated lipids and their correlation with mineralization in the light of its potential precocious diagnostic use. Cryosections from surgically explanted stenotic aortic valves (n=4) were studied matching Raman maps against specific histological patterns. Raman maps revealed the presence of phospholipids/triglycerides and cholesterol, which showed spatial overlapping with one another and Raman-identified hydroxyapatite. Moreover, the Raman patterns correlated with those displayed by both von-Kossa-calcium- and Nile-blue-stained serial cryosections. Raman analysis also provided the first identification of carotenoids, which co-localized with the identified lipid moieties. Additional fit concerned the distribution of collagen and elastin. The good correlation of Raman maps with high-affinity staining patterns proved that Raman microspectroscopy is a reliable tool in evaluating calcification degree, alteration/displacement of extracellular matrix components, and accumulation rate of different lipid forms in calcified heart valves. In addition, the novel identification of carotenoids supports the concept that valve stenosis is an atherosclerosis-like valve lesion, consistently with their previous Raman microspectroscopical identification inside atherosclerotic plaques.

  18. Topological visual mapping in robotics.

    Science.gov (United States)

    Romero, Anna; Cazorla, Miguel

    2012-08-01

    A key problem in robotics is the construction of a map from its environment. This map could be used in different tasks, like localization, recognition, obstacle avoidance, etc. Besides, the simultaneous location and mapping (SLAM) problem has had a lot of interest in the robotics community. This paper presents a new method for visual mapping, using topological instead of metric information. For that purpose, we propose prior image segmentation into regions in order to group the extracted invariant features in a graph so that each graph defines a single region of the image. Although others methods have been proposed for visual SLAM, our method is complete, in the sense that it makes all the process: it presents a new method for image matching; it defines a way to build the topological map; and it also defines a matching criterion for loop-closing. The matching process will take into account visual features and their structure using the graph transformation matching (GTM) algorithm, which allows us to process the matching and to remove out the outliers. Then, using this image comparison method, we propose an algorithm for constructing topological maps. During the experimentation phase, we will test the robustness of the method and its ability constructing topological maps. We have also introduced new hysteresis behavior in order to solve some problems found building the graph.

  19. Transport maps and dimension reduction for Bayesian computation

    KAUST Repository

    Marzouk, Youssef

    2015-01-01

    We introduce a new framework for efficient sampling from complex probability distributions, using a combination of optimal transport maps and the Metropolis-Hastings rule. The core idea is to use continuous transportation to transform typical Metropolis proposal mechanisms (e.g., random walks, Langevin methods) into non-Gaussian proposal distributions that can more effectively explore the target density. Our approach adaptively constructs a lower triangular transport map—an approximation of the Knothe-Rosenblatt rearrangement—using information from previous MCMC states, via the solution of an optimization problem. This optimization problem is convex regardless of the form of the target distribution. It is solved efficiently using a Newton method that requires no gradient information from the target probability distribution; the target distribution is instead represented via samples. Sequential updates enable efficient and parallelizable adaptation of the map even for large numbers of samples. We show that this approach uses inexact or truncated maps to produce an adaptive MCMC algorithm that is ergodic for the exact target distribution. Numerical demonstrations on a range of parameter inference problems show order-of-magnitude speedups over standard MCMC techniques, measured by the number of effectively independent samples produced per target density evaluation and per unit of wallclock time. We will also discuss adaptive methods for the construction of transport maps in high dimensions, where use of a non-adapted basis (e.g., a total order polynomial expansion) can become computationally prohibitive. If only samples of the target distribution, rather than density evaluations, are available, then we can construct high-dimensional transformations by composing sparsely parameterized transport maps with rotations of the parameter space. If evaluations of the target density and its gradients are available, then one can exploit the structure of the variational

  20. Transport maps and dimension reduction for Bayesian computation

    KAUST Repository

    Marzouk, Youssef

    2015-01-07

    We introduce a new framework for efficient sampling from complex probability distributions, using a combination of optimal transport maps and the Metropolis-Hastings rule. The core idea is to use continuous transportation to transform typical Metropolis proposal mechanisms (e.g., random walks, Langevin methods) into non-Gaussian proposal distributions that can more effectively explore the target density. Our approach adaptively constructs a lower triangular transport map—an approximation of the Knothe-Rosenblatt rearrangement—using information from previous MCMC states, via the solution of an optimization problem. This optimization problem is convex regardless of the form of the target distribution. It is solved efficiently using a Newton method that requires no gradient information from the target probability distribution; the target distribution is instead represented via samples. Sequential updates enable efficient and parallelizable adaptation of the map even for large numbers of samples. We show that this approach uses inexact or truncated maps to produce an adaptive MCMC algorithm that is ergodic for the exact target distribution. Numerical demonstrations on a range of parameter inference problems show order-of-magnitude speedups over standard MCMC techniques, measured by the number of effectively independent samples produced per target density evaluation and per unit of wallclock time. We will also discuss adaptive methods for the construction of transport maps in high dimensions, where use of a non-adapted basis (e.g., a total order polynomial expansion) can become computationally prohibitive. If only samples of the target distribution, rather than density evaluations, are available, then we can construct high-dimensional transformations by composing sparsely parameterized transport maps with rotations of the parameter space. If evaluations of the target density and its gradients are available, then one can exploit the structure of the variational

  1. Positivity of linear maps under tensor powers

    Energy Technology Data Exchange (ETDEWEB)

    Müller-Hermes, Alexander, E-mail: muellerh@ma.tum.de; Wolf, Michael M., E-mail: m.wolf@tum.de [Zentrum Mathematik, Technische Universität München, 85748 Garching (Germany); Reeb, David, E-mail: reeb.qit@gmail.com [Zentrum Mathematik, Technische Universität München, 85748 Garching (Germany); Institute for Theoretical Physics, Leibniz Universität Hannover, 30167 Hannover (Germany)

    2016-01-15

    We investigate linear maps between matrix algebras that remain positive under tensor powers, i.e., under tensoring with n copies of themselves. Completely positive and completely co-positive maps are trivial examples of this kind. We show that for every n ∈ ℕ, there exist non-trivial maps with this property and that for two-dimensional Hilbert spaces there is no non-trivial map for which this holds for all n. For higher dimensions, we reduce the existence question of such non-trivial “tensor-stable positive maps” to a one-parameter family of maps and show that an affirmative answer would imply the existence of non-positive partial transpose bound entanglement. As an application, we show that any tensor-stable positive map that is not completely positive yields an upper bound on the quantum channel capacity, which for the transposition map gives the well-known cb-norm bound. We, furthermore, show that the latter is an upper bound even for the local operations and classical communications-assisted quantum capacity, and that moreover it is a strong converse rate for this task.

  2. Positivity of linear maps under tensor powers

    International Nuclear Information System (INIS)

    Müller-Hermes, Alexander; Wolf, Michael M.; Reeb, David

    2016-01-01

    We investigate linear maps between matrix algebras that remain positive under tensor powers, i.e., under tensoring with n copies of themselves. Completely positive and completely co-positive maps are trivial examples of this kind. We show that for every n ∈ ℕ, there exist non-trivial maps with this property and that for two-dimensional Hilbert spaces there is no non-trivial map for which this holds for all n. For higher dimensions, we reduce the existence question of such non-trivial “tensor-stable positive maps” to a one-parameter family of maps and show that an affirmative answer would imply the existence of non-positive partial transpose bound entanglement. As an application, we show that any tensor-stable positive map that is not completely positive yields an upper bound on the quantum channel capacity, which for the transposition map gives the well-known cb-norm bound. We, furthermore, show that the latter is an upper bound even for the local operations and classical communications-assisted quantum capacity, and that moreover it is a strong converse rate for this task

  3. Simultaneous topography imaging and broadband nanomechanical mapping on atomic force microscope

    Science.gov (United States)

    Li, Tianwei; Zou, Qingze

    2017-12-01

    In this paper, an approach is proposed to achieve simultaneous imaging and broadband nanomechanical mapping of soft materials in air by using an atomic force microscope. Simultaneous imaging and nanomechanical mapping are needed, for example, to correlate the morphological and mechanical evolutions of the sample during dynamic phenomena such as the cell endocytosis process. Current techniques for nanomechanical mapping, however, are only capable of capturing static elasticity of the material, or the material viscoelasticity in a narrow frequency band around the resonant frequency(ies) of the cantilever used, not competent for broadband nanomechanical mapping, nor acquiring topography image of the sample simultaneously. These limitations are addressed in this work by enabling the augmentation of an excitation force stimuli of rich frequency spectrum for nanomechanical mapping in the imaging process. Kalman-filtering technique is exploited to decouple and split the mixed signals for imaging and mapping, respectively. Then the sample indentation generated is quantified online via a system-inversion method, and the effects of the indentation generated and the topography tracking error on the topography quantification are taken into account. Moreover, a data-driven feedforward-feedback control is utilized to track the sample topography. The proposed approach is illustrated through experimental implementation on a polydimethylsiloxane sample with a pre-fabricated pattern.

  4. Admixture mapping of end stage kidney disease genetic susceptibility using estimated mutual information ancestry informative markers

    Directory of Open Access Journals (Sweden)

    Geiger Dan

    2010-10-01

    Full Text Available Abstract Background The question of a genetic contribution to the higher prevalence and incidence of end stage kidney disease (ESKD among African Americans (AA remained unresolved, until recent findings using admixture mapping pointed to the association of a genomic locus on chromosome 22 with this disease phenotype. In the current study we utilize this example to demonstrate the utility of applying a multi-step admixture mapping approach. Methods A multi-step case only admixture mapping study, consisted of the following steps was designed: 1 Assembly of the sample dataset (ESKD AA; 2 Design of the estimated mutual information ancestry informative markers (n = 2016 screening panel 3; Genotyping the sample set whose size was determined by a power analysis (n = 576 appropriate for the initial screening panel; 4 Inference of local ancestry for each individual and identification of regions with increased AA ancestry using two different ancestry inference statistical approaches; 5 Enrichment of the initial screening panel; 6 Power analysis of the enriched panel 7 Genotyping of additional samples. 8 Re-analysis of the genotyping results to identify a genetic risk locus. Results The initial screening phase yielded a significant peak using the ADMIXMAP ancestry inference program applying case only statistics. Subgroup analysis of 299 ESKD patients with no history of diabetes yielded peaks using both the ANCESTRYMAP and ADMIXMAP ancestry inference programs. The significant peak was found on chromosome 22. Genotyping of additional ancestry informative markers on chromosome 22 that took into account linkage disequilibrium in the ancestral populations, and the addition of samples increased the statistical significance of the finding. Conclusions A multi-step admixture mapping analysis of AA ESKD patients replicated the finding of a candidate risk locus on chromosome 22, contributing to the heightened susceptibility of African Americans to develop non

  5. Hybrid Map-Based Navigation Method for Unmanned Ground Vehicle in Urban Scenario

    Directory of Open Access Journals (Sweden)

    Huiyan Chen

    2013-07-01

    Full Text Available To reduce the data size of metric map and map matching computational cost in unmanned ground vehicle self-driving navigation in urban scenarios, a metric-topological hybrid map navigation system is proposed in this paper. According to the different positioning accuracy requirements, urban areas are divided into strong constraint (SC areas, such as roads with lanes, and loose constraint (LC areas, such as intersections and open areas. As direction of the self-driving vehicle is provided by traffic lanes and global waypoints in the road network, a simple topological map is fit for the navigation in the SC areas. While in the LC areas, the navigation of the self-driving vehicle mainly relies on the positioning information. Simultaneous localization and mapping technology is used to provide a detailed metric map in the LC areas, and a window constraint Markov localization algorithm is introduced to achieve accurate position using laser scanner. Furthermore, the real-time performance of the Markov algorithm is enhanced by using a constraint window to restrict the size of the state space. By registering the metric maps into the road network, a hybrid map of the urban scenario can be constructed. Real unmanned vehicle mapping and navigation tests demonstrated the capabilities of the proposed method.

  6. ESTIMAP: Ecosystem services mapping at European scale

    OpenAIRE

    ZULIAN GRAZIA; PARACCHINI Maria-Luisa; MAES JOACHIM; LIQUETE GARCIA MARIA DEL CAMINO

    2013-01-01

    Mapping, visualization and the access to suitable data as a means to facilitate the dialogue among scientists, policy makers and the general public are among the most challenging issues within current ecosystem service science and application. Recently the attention on spatially explicit ways to map ecosystem services, at local, regional and global scale is increasing. This report presents ESTIMAP: a suite of models for a spatially explicit assessment of three ecosystem services (recreati...

  7. Going beyond the flood insurance rate map: insights from flood hazard map co-production

    Directory of Open Access Journals (Sweden)

    A. Luke

    2018-04-01

    Full Text Available Flood hazard mapping in the United States (US is deeply tied to the National Flood Insurance Program (NFIP. Consequently, publicly available flood maps provide essential information for insurance purposes, but they do not necessarily provide relevant information for non-insurance aspects of flood risk management (FRM such as public education and emergency planning. Recent calls for flood hazard maps that support a wider variety of FRM tasks highlight the need to deepen our understanding about the factors that make flood maps useful and understandable for local end users. In this study, social scientists and engineers explore opportunities for improving the utility and relevance of flood hazard maps through the co-production of maps responsive to end users' FRM needs. Specifically, two-dimensional flood modeling produced a set of baseline hazard maps for stakeholders of the Tijuana River valley, US, and Los Laureles Canyon in Tijuana, Mexico. Focus groups with natural resource managers, city planners, emergency managers, academia, non-profit, and community leaders refined the baseline hazard maps by triggering additional modeling scenarios and map revisions. Several important end user preferences emerged, such as (1 legends that frame flood intensity both qualitatively and quantitatively, and (2 flood scenario descriptions that report flood magnitude in terms of rainfall, streamflow, and its relation to an historic event. Regarding desired hazard map content, end users' requests revealed general consistency with mapping needs reported in European studies and guidelines published in Australia. However, requested map content that is not commonly produced included (1 standing water depths following the flood, (2 the erosive potential of flowing water, and (3 pluvial flood hazards, or flooding caused directly by rainfall. We conclude that the relevance and utility of commonly produced flood hazard maps can be most improved by illustrating

  8. A stratified two-stage sampling design for digital soil mapping in a Mediterranean basin

    Science.gov (United States)

    Blaschek, Michael; Duttmann, Rainer

    2015-04-01

    ESRI software (ArcGIS) extended by Hawth's Tools and later on its replacement the Geospatial Modelling Environment (GME). 88% of all desired points could actually be reached in the field and have been successfully sampled. Our results indicate that the sampled calibration and validation sets are representative for each other and could be successfully used as interpolation data for spatial prediction purposes. With respect to soil textural fractions, for instance, equal multivariate means and variance homogeneity were found for the two datasets as evidenced by significant (P > 0.05) Hotelling T²-test (2.3 with df1 = 3, df2 = 193) and Bartlett's test statistics (6.4 with df = 6). The multivariate prediction of clay, silt and sand content using a neural network residual cokriging approach reached an explained variance level of 56%, 47% and 63%. Thus, the presented case study is a successful example of considering readily available continuous information on soil forming factors such as geology and relief as stratifying variables for designing sampling schemes in digital soil mapping projects.

  9. Multisensor On-The-Go Mapping of Soil Organic Carbon Content

    DEFF Research Database (Denmark)

    Knadel, Maria; Thomsen, Anton Gårde; Greve, Mogens Humlekrog

    2011-01-01

    resulted in values as follows: root mean square error of prediction = 5.94; R2 = 0.84; and ratio of standard error of prediction to SD [RPD] = 2.3. This study showed that the quality of those maps can be improved and spatial sampling intensities can be reduced by incorporating auxiliary data as a source...... mapping SOC using a mobile sensor platform (MSP) and conventional grid sampling on a highly variable agricultural field in Denmark. Sixty-four samples collected on a 25-m grid were used to generate a reference map of SOC distribution using kriging. Mobile sensory data (visible–near infrared spectra...

  10. Normal mammogram detection based on local probability difference transforms and support vector machines

    International Nuclear Information System (INIS)

    Chiracharit, W.; Kumhom, P.; Chamnongthai, K.; Sun, Y.; Delp, E.J.; Babbs, C.F

    2007-01-01

    Automatic detection of normal mammograms, as a ''first look'' for breast cancer, is a new approach to computer-aided diagnosis. This approach may be limited, however, by two main causes. The first problem is the presence of poorly separable ''crossed-distributions'' in which the correct classification depends upon the value of each feature. The second problem is overlap of the feature distributions that are extracted from digitized mammograms of normal and abnormal patients. Here we introduce a new Support Vector Machine (SVM) based method utilizing with the proposed uncrossing mapping and Local Probability Difference (LPD). Crossed-distribution feature pairs are identified and mapped into a new features that can be separated by a zero-hyperplane of the new axis. The probability density functions of the features of normal and abnormal mammograms are then sampled and the local probability difference functions are estimated to enhance the features. From 1,000 ground-truth-known mammograms, 250 normal and 250 abnormal cases, including spiculated lesions, circumscribed masses or microcalcifications, are used for training a support vector machine. The classification results tested with another 250 normal and 250 abnormal sets show improved testing performances with 90% sensitivity and 89% specificity. (author)

  11. Kullback-Leibler Divergence-Based Differential Evolution Markov Chain Filter for Global Localization of Mobile Robots.

    Science.gov (United States)

    Martín, Fernando; Moreno, Luis; Garrido, Santiago; Blanco, Dolores

    2015-09-16

    One of the most important skills desired for a mobile robot is the ability to obtain its own location even in challenging environments. The information provided by the sensing system is used here to solve the global localization problem. In our previous work, we designed different algorithms founded on evolutionary strategies in order to solve the aforementioned task. The latest developments are presented in this paper. The engine of the localization module is a combination of the Markov chain Monte Carlo sampling technique and the Differential Evolution method, which results in a particle filter based on the minimization of a fitness function. The robot's pose is estimated from a set of possible locations weighted by a cost value. The measurements of the perceptive sensors are used together with the predicted ones in a known map to define a cost function to optimize. Although most localization methods rely on quadratic fitness functions, the sensed information is processed asymmetrically in this filter. The Kullback-Leibler divergence is the basis of a cost function that makes it possible to deal with different types of occlusions. The algorithm performance has been checked in a real map. The results are excellent in environments with dynamic and unmodeled obstacles, a fact that causes occlusions in the sensing area.

  12. Indoor self-localization via bluetooth low energy beacons

    NARCIS (Netherlands)

    Rizky Pratama, Azkario; Widyawan, Widyawan; Lazovik, Aliaksandr; Aiello, Marco

    2017-01-01

    Indoor localization is concerned with mapping sensory data to physical locations inside buildings. Location of a user or a mobile device is an essential part of the context, and is therefore very useful for pervasive computing applications. Many proposals exist for solving the localization problem,

  13. Role of adrenal vein sampling in primary aldosteronism: Impact of imaging, localization, and age.

    Science.gov (United States)

    Wachtel, Heather; Zaheer, Salman; Shah, Parth K; Trerotola, Scott O; Karakousis, Giorgos C; Roses, Robert E; Cohen, Debbie L; Fraker, Douglas L

    2016-04-01

    The role of adrenal vein sampling (AVS) has been debated, with some authorities advocating selective use in younger patients (≤40 years), and those localized by preoperative imaging. We examined our experience to determine the impact of AVS in patients who routinely underwent AVS with a high success rate. A retrospective cohort study was performed using a prospectively maintained database of patients referred for evaluation of PA (1997-2013). Patients were classified as localized (L) if a unilateral mass was identified on imaging, and non-localized (NL) otherwise. Of 367 patients, 94% (n = 345) underwent successful AVS. Seventy-two percent (n = 265) were L; AVS was lateralizing 58% (n = 214). AVS changed management in 43% of patients (n = 158). In patients ≤40 years, AVS changed management in 30% (n = 15). In patients ≤40 years with a ≥1 cm adrenal mass, 12% (n = 3) would have undergone unnecessary surgery based on imaging results alone; in patients >40 years with a ≥1 cm adrenal mass, 3% (n = 5) would have undergone wrong-side surgery, and 30% (n = 50) would have undergone unnecessary surgery based on imaging. AVS changed management in a significant minority of patients regardless of age and imaging findings. AVS should be routinely recommended in all patients with PA, to direct operative therapy. J. Surg. Oncol. 2016;113:532-537. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  14. Situations in Construction of 3D Mapping for Slam

    Directory of Open Access Journals (Sweden)

    Nguyen Hoang Thuy Trang

    2018-01-01

    Full Text Available Nowadays, the simultaneous localization and mapping (SLAM approach has become one of the most advanced engineering methods used for mobile robots to build maps in unknown or inaccessible spaces. Update maps before a certain area while tracking current location and distance. The motivation behind writing this paper is mainly to help us better understand about SLAM and the study situation of SLAM in the world today. Through this, we find the optimal algorithm for moving robots in three dimensions.

  15. Missing value imputation for epistatic MAPs

    LENUS (Irish Health Repository)

    Ryan, Colm

    2010-04-20

    Abstract Background Epistatic miniarray profiling (E-MAPs) is a high-throughput approach capable of quantifying aggravating or alleviating genetic interactions between gene pairs. The datasets resulting from E-MAP experiments typically take the form of a symmetric pairwise matrix of interaction scores. These datasets have a significant number of missing values - up to 35% - that can reduce the effectiveness of some data analysis techniques and prevent the use of others. An effective method for imputing interactions would therefore increase the types of possible analysis, as well as increase the potential to identify novel functional interactions between gene pairs. Several methods have been developed to handle missing values in microarray data, but it is unclear how applicable these methods are to E-MAP data because of their pairwise nature and the significantly larger number of missing values. Here we evaluate four alternative imputation strategies, three local (Nearest neighbor-based) and one global (PCA-based), that have been modified to work with symmetric pairwise data. Results We identify different categories for the missing data based on their underlying cause, and show that values from the largest category can be imputed effectively. We compare local and global imputation approaches across a variety of distinct E-MAP datasets, showing that both are competitive and preferable to filling in with zeros. In addition we show that these methods are effective in an E-MAP from a different species, suggesting that pairwise imputation techniques will be increasingly useful as analogous epistasis mapping techniques are developed in different species. We show that strongly alleviating interactions are significantly more difficult to predict than strongly aggravating interactions. Finally we show that imputed interactions, generated using nearest neighbor methods, are enriched for annotations in the same manner as measured interactions. Therefore our method potentially

  16. Boat sampling

    International Nuclear Information System (INIS)

    Citanovic, M.; Bezlaj, H.

    1994-01-01

    This presentation describes essential boat sampling activities: on site boat sampling process optimization and qualification; boat sampling of base material (beltline region); boat sampling of weld material (weld No. 4); problems accompanied with weld crown varieties, RPV shell inner radius tolerance, local corrosion pitting and water clarity. The equipment used for boat sampling is described too. 7 pictures

  17. Geologic Mapping and Paired Geochemical-Paleomagnetic Sampling of Reference Sections in the Grande Ronde Basalt: An Example from the Bingen Section, Columbia River Gorge, Washington

    Science.gov (United States)

    Sawlan, M.; Hagstrum, J. T.; Wells, R. E.

    2011-12-01

    We have completed comprehensive geochemical (GC) and paleomagnetic (PM) sampling of individual lava flows from eight reference stratigraphic sections in the Grande Ronde Basalt (GRB), Columbia River Basalt Group [Hagstrum et al., 2009, GSA Ann. Mtg, Portland (abst); Hagstrum et al., 2010, AGU Fall Mtg, San Francisco (abst)]. These sections, distributed across the Columbia Plateau and eastern Columbia River Gorge, contain as many as 30 flows, are up to 670 m thick, span upper magneto-stratigraphic zones R2 and N2, and, in some locations, also contain one or more N1 flows. In concert with GC and PM sampling, we have carried out detailed geologic mapping of these sections, typically at a scale of 1:3,000 to 1:5,000, using GPS, digital imagery from the National Aerial Imagery Program (NAIP), and compilation in GIS. GRB member and informal unit names of Reidel et al. [1989, GSA Sp. Paper 239] generally have been adopted, although two new units are identified and named within the N2 zone. Notably, a distinctive PM direction for intercalated lavas of several lower N2 units indicates coeval eruption of compositionally distinct units; this result contrasts with the scenario of serial stratigraphic succession of GRB units proposed by Reidel et al. [1989]. Our objectives in the mapping include: Confirming the integrity of the stratigraphic sequences by documenting flow contacts and intraflow horizons (changes in joint patterns or vesicularity); assessing fault displacements; and, establishing precisely located samples in geologic context such that selected sites can be unambiguously reoccupied. A geologic map and GC-PM data for the Bingen section, along the north side of the Columbia River, are presented as an example of our GRB reference section mapping and sampling. One of our thicker sections (670 m) along which 30 flows are mapped, the Bingen section spans 7 km along WA State Hwy 14, from near the Hood River Bridge ESE to Locke Lake. This section cuts obliquely through a

  18. Soil organic carbon content assessment in a heterogeneous landscape: comparison of digital soil mapping and visible and near Infrared spectroscopy approaches

    Science.gov (United States)

    Michot, Didier; Fouad, Youssef; Pascal, Pichelin; Viaud, Valérie; Soltani, Inès; Walter, Christian

    2017-04-01

    This study aims are: i) to assess SOC content distribution according to the global soil map (GSM) project recommendations in a heterogeneous landscape ; ii) to compare the prediction performance of digital soil mapping (DSM) and visible-near infrared (Vis-NIR) spectroscopy approaches. The study area of 140 ha, located at Plancoët, surrounds the unique mineral spring water of Brittany (Western France). It's a hillock characterized by a heterogeneous landscape mosaic with different types of forest, permanent pastures and wetlands along a small coastal river. We acquired two independent datasets: j) 50 points selected using a conditioned Latin hypercube sampling (cLHS); jj) 254 points corresponding to the GSM grid. Soil samples were collected in three layers (0-5, 20-25 and 40-50cm) for both sampling strategies. SOC content was only measured in cLHS soil samples, while Vis-NIR spectra were measured on all the collected samples. For the DSM approach, a machine-learning algorithm (Cubist) was applied on the cLHS calibration data to build rule-based models linking soil carbon content in the different layers with environmental covariates, derived from digital elevation model, geological variables, land use data and existing large scale soil maps. For the spectroscopy approach, we used two calibration datasets: k) the local cLHS ; kk) a subset selected from the regional spectral database of Brittany after a PCA with a hierarchical clustering analysis and spiked by local cLHS spectra. The PLS regression algorithm with "leave-one-out" cross validation was performed for both calibration datasets. SOC contents for the 3 layers of the GSM grid were predicted using the different approaches and were compared with each other. Their prediction performance was evaluated by the following parameters: R2, RMSE and RPD. Both approaches led to satisfactory predictions for SOC content with an advantage for the spectral approach, particularly as regards the pertinence of the variation

  19. Taking potential probability function maps to the local scale and matching them with land use maps

    Science.gov (United States)

    Garg, Saryu; Sinha, Vinayak; Sinha, Baerbel

    2013-04-01

    Source-Receptor models have been developed using different methods. Residence-time weighted concentration back trajectory analysis and Potential Source Contribution Function (PSCF) are the two most popular techniques for identification of potential sources of a substance in a defined geographical area. Both techniques use back trajectories calculated using global models and assign values of probability/concentration to various locations in an area. These values represent the probability of threshold exceedances / the average concentration measured at the receptor in air masses with a certain residence time over a source area. Both techniques, however, have only been applied to regional and long-range transport phenomena due to inherent limitation with respect to both spatial accuracy and temporal resolution of the of back trajectory calculations. Employing the above mentioned concepts of residence time weighted concentration back-trajectory analysis and PSCF, we developed a source-receptor model capable of identifying local and regional sources of air pollutants like Particulate Matter (PM), NOx, SO2 and VOCs. We use 1 to 30 minute averages of concentration values and wind direction and speed from a single receptor site or from multiple receptor sites to trace the air mass back in time. The model code assumes all the atmospheric transport to be Lagrangian and linearly extrapolates air masses reaching the receptor location, backwards in time for a fixed number of steps. We restrict the model run to the lifetime of the chemical species under consideration. For long lived species the model run is limited to 180 trees/gridsquare); moderate concentrations for agricultural lands with low tree density (1.5-2.5 ppbv for 250 μg/m3 for traffic hotspots in Chandigarh City are observed. Based on the validation against the land use maps, the model appears to do an excellent job in source apportionment and identifying emission hotspots. Acknowledgement: We thank the IISER

  20. Cognitive Mapping Based on Conjunctive Representations of Space and Movement

    Directory of Open Access Journals (Sweden)

    Taiping Zeng

    2017-11-01

    Full Text Available It is a challenge to build robust simultaneous localization and mapping (SLAM system in dynamical large-scale environments. Inspired by recent findings in the entorhinal–hippocampal neuronal circuits, we propose a cognitive mapping model that includes continuous attractor networks of head-direction cells and conjunctive grid cells to integrate velocity information by conjunctive encodings of space and movement. Visual inputs from the local view cells in the model provide feedback cues to correct drifting errors of the attractors caused by the noisy velocity inputs. We demonstrate the mapping performance of the proposed cognitive mapping model on an open-source dataset of 66 km car journey in a 3 km × 1.6 km urban area. Experimental results show that the proposed model is robust in building a coherent semi-metric topological map of the entire urban area using a monocular camera, even though the image inputs contain various changes caused by different light conditions and terrains. The results in this study could inspire both neuroscience and robotic research to better understand the neural computational mechanisms of spatial cognition and to build robust robotic navigation systems in large-scale environments.

  1. Aerial image geolocalization by matching its line structure with route map

    Science.gov (United States)

    Kunina, I. A.; Terekhin, A. P.; Khanipov, T. M.; Kuznetsova, E. G.; Nikolaev, D. P.

    2017-03-01

    The classic way of aerial photographs geolocation is to bind their local coordinates to a geographic coordinate system using GPS and IMU data. At the same time the possibility of geolocation in a jammed navigation field is also of interest for practical purposes. In this paper we consider one approach to visual localization relatively to a vector road map without GPS. We suggest a geolocalization algorithm which detects image line segments and looks for a geometrical transformation which provides the best mapping between the obtained segments set and line segments in the road map. We consider IMU and altimeter data still known which allows to work with orthorectified images. The problem is hence reduced to a search for a transformation which contains an arbitrary shift and bounded rotation and scaling relatively to the vector map. These parameters are estimated using RANSAC by matching straight line segments from the image to vector map segments. We also investigate how the proposed algorithm's stability is influenced by segment coordinates (two spatial and one angular).

  2. Mapping the logics in practice oriented competence development

    DEFF Research Database (Denmark)

    Tamborg, Andreas Lindenskov; Allsopp, Benjamin B.; Fougt, Simon Skov

    In this paper we investigate the role of the local supervisor when implementing a mathematics teacher training program based on Action Learning (Misfeldt et al. 2014, Plauborg et al. 2007). Using data from interviews of teachers, local supervisors and school managers we examine the arising...... expectations on the local supervisor and how these expectations influence the program’s ability to support teachers in their professional development. We do so by using Clarke’s (2009) Situational Analysis and Arcform notation (Allsopp 2013) to map the actors’ relation to the supervisor. We see that the local...

  3. Mapping and Measuring European Local Governments’ Priorities for a Sustainable and Low-Carbon Energy Future

    Directory of Open Access Journals (Sweden)

    Stelios Grafakos

    2015-10-01

    Full Text Available The main objective of this article is to assess the priorities of local governments (LGs in Europe regarding climate change mitigation technologies evaluation in the electricity sector and to provide important insights for energy policy design. The study applies a hybrid weighting methodology to elicit LGs’ preferences in a constructive and iterative way regarding the evaluation criteria of low-carbon energy technologies. Furthermore, the study employs three data collection and preference elicitation methods, namely: survey, workshop, and webinar. The study was conducted across thirty one (31 European LGs that were categorized according to three variables: population size, geographical region and gross domestic product (GDP per capita. The analysis shows that “CO2 emissions” is the most important criterion among European LGs, followed by “mortality and morbidity” and “ecosystem damages”. The results illustrate the potential synergies of climate and energy policies for addressing both CO2 emissions and air pollution. It was also found, based on a correlation analysis, that LGs with higher GDP per capita tend to provide higher weights to criteria related to security of energy supply and technological innovation. The current study provides insights on the actual LGs’ priorities that are important to consider during low-carbon energy technologies evaluation and energy policy design. Interestingly, the results of the European LGs’ preferences clearly show that the EU climate policy objectives have reached different levels of governance—and at this particular case, the local level. Furthermore, the developed methodology could be applied at different geographical regions to map other regions’ LG priorities, but also at a group decision making context to elicit relevant stakeholders’ preferences regarding low-carbon energy technologies and policy objectives.

  4. Empirical PPGIS/PGIS mapping of ecosystem services

    DEFF Research Database (Denmark)

    Brown, Gregory G; Fagerholm, Nora

    2015-01-01

    demonstrate high potential for the identification of ecosystem services, especially cultural services, there has been no review to evaluate the methods to identify best practice. Through examination of peer-reviewed, empirical PPGIS/PGIS studies, we describe the types of ecosystem services mapped, the spatial...... of experimental design and long-term case studies where the influence of mapped ecosystem services on land use decisions can be assessed....... mapping methods, the sampling approaches and range of participants, the types of spatial analyses performed, and the methodological trade-offs associated with each PPGIS/PGIS mapping approach. We found that multiple methods were implemented in nearly 30 case studies worldwide with the mapping of cultural...

  5. Whole-brain activity mapping onto a zebrafish brain atlas

    Science.gov (United States)

    Randlett, Owen; Wee, Caroline L.; Naumann, Eva A.; Nnaemeka, Onyeka; Schoppik, David; Fitzgerald, James E.; Portugues, Ruben; Lacoste, Alix M.B.; Riegler, Clemens; Engert, Florian; Schier, Alexander F.

    2015-01-01

    In order to localize the neural circuits involved in generating behaviors, it is necessary to assign activity onto anatomical maps of the nervous system. Using brain registration across hundreds of larval zebrafish, we have built an expandable open source atlas containing molecular labels and anatomical region definitions, the Z-Brain. Using this platform and immunohistochemical detection of phosphorylated-Extracellular signal-regulated kinase (ERK/MAPK) as a readout of neural activity, we have developed a system to create and contextualize whole brain maps of stimulus- and behavior-dependent neural activity. This MAP-Mapping (Mitogen Activated Protein kinase – Mapping) assay is technically simple, fast, inexpensive, and data analysis is completely automated. Since MAP-Mapping is performed on fish that are freely swimming, it is applicable to nearly any stimulus or behavior. We demonstrate the utility of our high-throughput approach using hunting/feeding, pharmacological, visual and noxious stimuli. The resultant maps outline hundreds of areas associated with behaviors. PMID:26778924

  6. Completing the Picture: Importance of Considering Participatory Mapping for REDD+ Measurement, Reporting and Verification (MRV.

    Directory of Open Access Journals (Sweden)

    Guillaume Beaudoin

    Full Text Available Remote sensing has been widely used for mapping land cover and is considered key to monitoring changes in forest areas in the REDD+ Measurement, Reporting and Verification (MRV system. But Remote Sensing as a desk study cannot capture the whole picture; it also requires ground checking. Therefore, complementing remote sensing analysis using participatory mapping can help provide information for an initial forest cover assessment, gain better understanding of how local land use might affect changes, and provide a way to engage local communities in REDD+. Our study looked at the potential of participatory mapping in providing complementary information for remotely sensed maps. The research sites were located in different ecological and socio-economic contexts in the provinces of Papua, West Kalimantan and Central Java, Indonesia. Twenty-one maps of land cover and land use were drawn with local community participation during focus group discussions in seven villages. These maps, covering a total of 270,000ha, were used to add information to maps developed using remote sensing, adding 39 land covers to the eight from our initial desk assessment. They also provided additional information on drivers of land use and land cover change, resource areas, territory claims and land status, which we were able to correlate to understand changes in forest cover. Incorporating participatory mapping in the REDD+ MRV protocol would help with initial remotely sensed land classifications, stratify an area for ground checks and measurement plots, and add other valuable social data not visible at the RS scale. Ultimately, it would provide a forum for local communities to discuss REDD+ activities and develop a better understanding of REDD+.

  7. A FAST AND FLEXIBLE METHOD FOR META-MAP BUILDING FOR ICP BASED SLAM

    Directory of Open Access Journals (Sweden)

    A. Kurian

    2016-06-01

    Full Text Available Recent developments in LiDAR sensors make mobile mapping fast and cost effective. These sensors generate a large amount of data which in turn improves the coverage and details of the map. Due to the limited range of the sensor, one has to collect a series of scans to build the entire map of the environment. If we have good GNSS coverage, building a map is a well addressed problem. But in an indoor environment, we have limited GNSS reception and an inertial solution, if available, can quickly diverge. In such situations, simultaneous localization and mapping (SLAM is used to generate a navigation solution and map concurrently. SLAM using point clouds possesses a number of computational challenges even with modern hardware due to the shear amount of data. In this paper, we propose two strategies for minimizing the cost of computation and storage when a 3D point cloud is used for navigation and real-time map building. We have used the 3D point cloud generated by Leica Geosystems's Pegasus Backpack which is equipped with Velodyne VLP-16 LiDARs scanners. To improve the speed of the conventional iterative closest point (ICP algorithm, we propose a point cloud sub-sampling strategy which does not throw away any key features and yet significantly reduces the number of points that needs to be processed and stored. In order to speed up the correspondence finding step, a dual kd-tree and circular buffer architecture is proposed. We have shown that the proposed method can run in real time and has excellent navigation accuracy characteristics.

  8. Accounting for access costs in validation of soil maps

    NARCIS (Netherlands)

    Yang, Lin; Brus, Dick J.; Zhu, A.X.; Li, Xinming; Shi, Jingjing

    2018-01-01

    The quality of soil maps can best be estimated by collecting additional data at locations selected by probability sampling. These data can be used in design-based estimation of map quality measures such as the population mean of the squared prediction errors (MSE) for continuous soil maps and

  9. Mapping urban poverty for local governance in an Indian mega-city: The case of Delhi

    NARCIS (Netherlands)

    Baud, I.; Sridharan, N.; Pfeffer, K.

    2008-01-01

    The article maps urban poverty, using the `livelihoods assets framework' to develop a new index of multiple deprivation, examining the implications for area and sector targeting by policy-makers. This article deals with the index and the results for Delhi. The study maps: the spatial concentration

  10. Assessment of Convolution Neural Networks for Surficial Geology Mapping in the South Rae Geological Region, Northwest Territories, Canada

    Directory of Open Access Journals (Sweden)

    Rasim Latifovic

    2018-02-01

    Full Text Available Mapping of surficial geology is an important requirement for broadening the geoscience database of northern Canada. Surficial geology maps are an integral data source for mineral and energy exploration. Moreover, they provide information such as the location of gravels and sands, which are important for infrastructure development. Currently, surficial geology maps are produced through expert interpretation of aerial photography and field data. However, interpretation is known to be subjective, labour-intensive and difficult to repeat. The expert knowledge required for interpretation can be challenging to maintain and transfer. In this research, we seek to assess the potential of deep neural networks to aid surficial geology mapping by providing an objective surficial materials initial layer that experts can modify to speed map development and improve consistency between mapped areas. Such an approach may also harness expert knowledge in a way that is transferable to unmapped areas. For this purpose, we assess the ability of convolution neural networks (CNN to predict surficial geology classes under two sampling scenarios. In the first scenario, a CNN uses samples collected over the area to be mapped. In the second, a CNN trained over one area is then applied to locations where the available samples were not used in training the network. The latter case is important, as a collection of in situ training data can be costly. The evaluation of the CNN was carried out using aerial photos, Landsat reflectance, and high-resolution digital elevation data over five areas within the South Rae geological region of Northwest Territories, Canada. The results are encouraging, with the CNN generating average accuracy of 76% when locally trained. For independent test areas (i.e., trained over one area and applied over other, accuracy dropped to 59–70% depending on the classes selected for mapping. In the South Rae region, significant confusion was found

  11. A microsatellite linkage map of Drosophila mojavensis

    Directory of Open Access Journals (Sweden)

    Schully Sheri

    2004-05-01

    Full Text Available Abstract Background Drosophila mojavensis has been a model system for genetic studies of ecological adaptation and speciation. However, despite its use for over half a century, no linkage map has been produced for this species or its close relatives. Results We have developed and mapped 90 microsatellites in D. mojavensis, and we present a detailed recombinational linkage map of 34 of these microsatellites. A slight excess of repetitive sequence was observed on the X-chromosome relative to the autosomes, and the linkage groups have a greater recombinational length than the homologous D. melanogaster chromosome arms. We also confirmed the conservation of Muller's elements in 23 sequences between D. melanogaster and D. mojavensis. Conclusions The microsatellite primer sequences and localizations are presented here and made available to the public. This map will facilitate future quantitative trait locus mapping studies of phenotypes involved in adaptation or reproductive isolation using this species.

  12. Interpolation methods for creating a scatter radiation exposure map

    International Nuclear Information System (INIS)

    Gonçalves, Elicardo A. de S.; Gomes, Celio S.; Lopes, Ricardo T.; Oliveira, Luis F. de; Anjos, Marcelino J. dos; Oliveira, Davi F.

    2017-01-01

    A well know way for best comprehension of radiation scattering during a radiography is to map exposure over the space around the source and sample. This map is done measuring exposure in points regularly spaced, it means, measurement will be placed in localization chosen by increasing a regular steps from a starting point, along the x, y and z axes or even radial and angular coordinates. However, it is not always possible to maintain the accuracy of the steps throughout the entire space, or there will be regions of difficult access where the regularity of the steps will be impaired. This work intended to use some interpolation techniques that work with irregular steps, and to compare their results and their limits. It was firstly done angular coordinates, and tested in lack of some points. Later, in the same data was performed the Delaunay tessellation interpolation ir order to compare. Computational and graphic treatments was done with the GNU OCTAVE software and its image-processing package. Real data was acquired from a bunker where a 6 MeV betatron can be used to produce radiation scattering. (author)

  13. Interpolation methods for creating a scatter radiation exposure map

    Energy Technology Data Exchange (ETDEWEB)

    Gonçalves, Elicardo A. de S., E-mail: elicardo.goncalves@ifrj.edu.br [Instituto Federal do Rio de Janeiro (IFRJ), Paracambi, RJ (Brazil); Gomes, Celio S.; Lopes, Ricardo T. [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Oliveira, Luis F. de; Anjos, Marcelino J. dos; Oliveira, Davi F. [Universidade do Estado do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Física

    2017-07-01

    A well know way for best comprehension of radiation scattering during a radiography is to map exposure over the space around the source and sample. This map is done measuring exposure in points regularly spaced, it means, measurement will be placed in localization chosen by increasing a regular steps from a starting point, along the x, y and z axes or even radial and angular coordinates. However, it is not always possible to maintain the accuracy of the steps throughout the entire space, or there will be regions of difficult access where the regularity of the steps will be impaired. This work intended to use some interpolation techniques that work with irregular steps, and to compare their results and their limits. It was firstly done angular coordinates, and tested in lack of some points. Later, in the same data was performed the Delaunay tessellation interpolation ir order to compare. Computational and graphic treatments was done with the GNU OCTAVE software and its image-processing package. Real data was acquired from a bunker where a 6 MeV betatron can be used to produce radiation scattering. (author)

  14. Geologic mapping procedure: Final draft

    International Nuclear Information System (INIS)

    1987-09-01

    Geologic mapping will provide a baseline record of the subsurface geology in the shafts and drifts of the Exploratory Shaft Facility (ESF). This information will be essential in confirming the specific repository horizon, selecting representative locations for the in situ tests, providing information for construction and decommissioning seal designs, documenting the excavation effects, and in providing information for performance assessment, which relates to the ultimate suitability of the site as a nuclear waste repository. Geologic mapping will be undertaken on the walls and roof, and locally on the floor within the completed At-Depth Facility (ADF) and on the walls of the two access shafts. Periodic mapping of the exposed face may be conducted during construction of the ADF. The mapping will be oriented toward the collection and presentation of geologic information in an engineering format and the portrayal of detailed stratigraphic information which may be useful in confirmation of drillhole data collected as part of the surface-based testing program. Geologic mapping can be considered as a predictive tool as well as a means of checking design assumptions. This document provides a description of the required procedures for geologic mapping for the ESF. Included in this procedure is information that qualified technical personnel can use to collect the required types of geologic descriptions, at the appropriate level of detail. 5 refs., 3 figs., 1 tab

  15. Epileptogenic zone localization using magnetoencephalography predicts seizure freedom in epilepsy surgery

    Science.gov (United States)

    Englot, Dario J.; Nagarajan, Srikantan S.; Imber, Brandon S.; Raygor, Kunal P.; Honma, Susanne M.; Mizuiri, Danielle; Mantle, Mary; Knowlton, Robert C.; Kirsch, Heidi E.; Chang, Edward F.

    2015-01-01

    Objective The efficacy of epilepsy surgery depends critically upon successful localization of the epileptogenic zone. Magnetoencephalography (MEG) enables non-invasive detection of interictal spike activity in epilepsy, which can then be localized in three dimensions using magnetic source imaging (MSI) techniques. However, the clinical value of MEG in the pre-surgical epilepsy evaluation is not fully understood, as studies to date are limited by either a lack of long-term seizure outcomes or small sample size. Methods We performed a retrospective cohort study of focal epilepsy patients who received MEG for interictal spike mapping followed by surgical resection at our institution. Results We studied 132 surgical patients, with mean post-operative follow-up of 3.6 years (minimum 1 year). Dipole source modelling was successful in 103 (78%) patients, while no interictal spikes were seen in others. Among patients with successful dipole modelling, MEG findings were concordant with and specific to: i) the region of resection in 66% of patients, ii) invasive electrocorticography (ECoG) findings in 67% of individuals, and iii) the MRI abnormality in 74% of cases. MEG showed discordant lateralization in ~5% of cases. After surgery, 70% of all patients achieved seizure-freedom (Engel class I outcome). Whereas 85% of patients with concordant and specific MEG findings became seizure-free, this outcome was achieved by only 37% of individuals with MEG findings that were non-specific or discordant with the region of resection (χ2 = 26.4, p < 0.001). MEG reliability was comparable in patients with or without localized scalp EEG, and overall, localizing MEG findings predicted seizure freedom with an odds ratio of 5.11 (2.23–11.8, 95% CI). Significance MEG is a valuable tool for non-invasive interictal spike mapping in epilepsy surgery, including patients with non-localized findings on long-term EEG monitoring, and localization of the epileptogenic zone using MEG is associated

  16. Mapping the EORTC QLQ-C30 onto the EQ-5D-3L: assessing the external validity of existing mapping algorithms.

    Science.gov (United States)

    Doble, Brett; Lorgelly, Paula

    2016-04-01

    To determine the external validity of existing mapping algorithms for predicting EQ-5D-3L utility values from EORTC QLQ-C30 responses and to establish their generalizability in different types of cancer. A main analysis (pooled) sample of 3560 observations (1727 patients) and two disease severity patient samples (496 and 93 patients) with repeated observations over time from Cancer 2015 were used to validate the existing algorithms. Errors were calculated between observed and predicted EQ-5D-3L utility values using a single pooled sample and ten pooled tumour type-specific samples. Predictive accuracy was assessed using mean absolute error (MAE) and standardized root-mean-squared error (RMSE). The association between observed and predicted EQ-5D utility values and other covariates across the distribution was tested using quantile regression. Quality-adjusted life years (QALYs) were calculated using observed and predicted values to test responsiveness. Ten 'preferred' mapping algorithms were identified. Two algorithms estimated via response mapping and ordinary least-squares regression using dummy variables performed well on number of validation criteria, including accurate prediction of the best and worst QLQ-C30 health states, predicted values within the EQ-5D tariff range, relatively small MAEs and RMSEs, and minimal differences between estimated QALYs. Comparison of predictive accuracy across ten tumour type-specific samples highlighted that algorithms are relatively insensitive to grouping by tumour type and affected more by differences in disease severity. Two of the 'preferred' mapping algorithms suggest more accurate predictions, but limitations exist. We recommend extensive scenario analyses if mapped utilities are used in cost-utility analyses.

  17. Improved Culture Medium (TiKa) for Mycobacterium avium Subspecies Paratuberculosis (MAP) Matches qPCR Sensitivity and Reveals Significant Proportions of Non-viable MAP in Lymphoid Tissue of Vaccinated MAP Challenged Animals

    DEFF Research Database (Denmark)

    Bull, Tim J.; Munshil, Tulika; Melvang, Heidi Mikkelsen

    2017-01-01

    The quantitative detection of viable pathogen load is an important tool in determining the degree of infection in animals and contamination of foodstuffs. Current conventional culture methods are limited in their ability to determine these levels in Mycobacterium avium subspecies paratuberculosis......Ka culture equates well with qPCR and provides important evidence that accuracy in estimating viable MAP load using DNA tests alone may vary significantly between samples of mucosal and lymphatic origin....... (MAP) due to slow growth, clumping and low recoverability issues. The principle goal of this study was to evaluate a novel culturing process (TiKa) with unique ability to stimulate MAP growth from low sample loads and dilutions. We demonstrate it was able to stimulate a mean 29-fold increase...

  18. Detection of minute strain in very local areas of materials by using an X-ray microbeam

    CERN Document Server

    Matsui, J; Tsusaka, Y; Kimura, S

    2003-01-01

    In order to analyze the local minute strain in semiconductor materials and devices, we have demonstrated formation of X-ray microbeams by using asymmetric Bragg reflections of the crystal and a zone plate or cylindrical mirror combined with synchrotron radiation. A series of X-ray rocking curves have been obtained by scanning the sample with using the X-ray microbeam. In addition, reciprocal space maps have also been obtained by inserting an analyzer crystal behind the sample. From these data, information on the strain distribution can be obtained for various samples, such as the strain near SiO sub 2 /Si film edges, that in silicon-on-insulator (SOI) crystals, and that in InGaAsP semiconductor laser stripes. (author)

  19. Necessary conditions for cartographic communication and navigation with guide maps

    OpenAIRE

    Wakabayashi, Yoshiki

    2007-01-01

    The aim of this study was to examine the necessary conditions for the communication of geographic information and navigation with guide maps by conducting two experiments. The results of the first experiment showed that not only local landmarks but also the names of well-known places were necessary to identify the location indicated by the map. The spatial abilities of the subject also affected the performance of the identification task when the map indicated unfamiliar places. The second exp...

  20. Assessing the Suitability of Future Multi- and Hyperspectral Satellite Systems for Mapping the Spatial Distribution of Norway Spruce Timber Volume

    Directory of Open Access Journals (Sweden)

    Sascha Nink

    2015-09-01

    Full Text Available The availability of accurate and timely information on timber volume is important for supporting operational forest management. One option is to combine statistical concepts (e.g., small area estimates with specifically designed terrestrial sampling strategies to provide estimations also on the level of administrative units such as forest districts. This may suffice for economic assessments, but still fails to provide spatially explicit information on the distribution of timber volume within these management units. This type of information, however, is needed for decision-makers to design and implement appropriate management operations. The German federal state of Rhineland-Palatinate is currently implementing an object-oriented database that will also allow the direct integration of Earth observation data products. This work analyzes the suitability of forthcoming multi- and hyperspectral satellite imaging systems for producing local distribution maps for timber volume of Norway spruce, one of the most economically important tree species. In combination with site-specific inventory data, fully processed hyperspectral data sets (HyMap were used to simulate datasets of the forthcoming EnMAP and Sentinel-2 systems to establish adequate models for estimating timber volume maps. The analysis included PLS regression and the k-NN method. Root Mean Square Errors between 21.6% and 26.5% were obtained, where k-NN performed slightly better than PLSR. It was concluded that the datasets of both simulated sensor systems fulfill accuracy requirements to support local forest management operations and could be used in synergy. Sentinel-2 can provide meaningful volume distribution maps in higher geometric resolution, while EnMAP, due to its hyperspectral coverage, can contribute complementary information, e.g., on biophysical conditions.