WorldWideScience

Sample records for multi-temporal database accuracy

  1. Robust Automated Image Co-Registration of Optical Multi-Sensor Time Series Data: Database Generation for Multi-Temporal Landslide Detection

    Directory of Open Access Journals (Sweden)

    Robert Behling

    2014-03-01

    Full Text Available Reliable multi-temporal landslide detection over longer periods of time requires multi-sensor time series data characterized by high internal geometric stability, as well as high relative and absolute accuracy. For this purpose, a new methodology for fully automated co-registration has been developed allowing efficient and robust spatial alignment of standard orthorectified data products originating from a multitude of optical satellite remote sensing data of varying spatial resolution. Correlation-based co-registration uses world-wide available terrain corrected Landsat Level 1T time series data as the spatial reference, ensuring global applicability. The developed approach has been applied to a multi-sensor time series of 592 remote sensing datasets covering an approximately 12,000 km2 area in Southern Kyrgyzstan (Central Asia strongly affected by landslides. The database contains images acquired during the last 26 years by Landsat (ETM, ASTER, SPOT and RapidEye sensors. Analysis of the spatial shifts obtained from co-registration has revealed sensor-specific alignments ranging between 5 m and more than 400 m. Overall accuracy assessment of these alignments has resulted in a high relative image-to-image accuracy of 17 m (RMSE and a high absolute accuracy of 23 m (RMSE for the whole co-registered database, making it suitable for multi-temporal landslide detection at a regional scale in Southern Kyrgyzstan.

  2. The Multi-Temporal Database of Planetary Image Data (MUTED): A database to support the identification of surface changes and short-lived surface processes

    Science.gov (United States)

    Erkeling, G.; Luesebrink, D.; Hiesinger, H.; Reiss, D.; Heyer, T.; Jaumann, R.

    2016-06-01

    Images of Mars taken by spacecraft in the last few decades indicate that the landscape has changed and that current processes are continuously changing the surface. The modifications of the landscape are caused by exogenic processes including eolian activity, mass movement, the growth and retreat of the polar caps, glacial processes and crater-forming impacts. In particular the High Resolution Stereo Camera (HRSC) on board Mars Express (MEx) and the Context Camera (CTX) on board the Mars Reconnaissance Orbiter (MRO) cover large areas at high resolution and thus are particularly well-suited to detect the extent and origin of surface changes on Mars. Multi-temporal observations of variable features on Mars became possible by the increasing number of repeated image acquisitions of the same surface areas. To support the investigation of surface changes that represents a key element in martian research, we developed MUTED, the "Multi-Temporal Database of Planetary Image Data", which is a tool for the identification of the spatial and multi-temporal coverage of planetary image data from Mars. Using MUTED, scientists are able to identify the location, number, and time range of acquisitions of overlapping images from, for example, HRSC and CTX. MUTED also includes images from other planetary datasets such as those of the Mars Orbiter Camera (MOC), the Thermal Emission Imaging System (THEMIS), and the High Resolution Imaging Science Experiment (HiRISE). The database supports the identification and analysis of surface changes and short-lived surface processes on Mars based on fast automatic planetary image database queries. From the multi-temporal planetary image database and investigations based on multi-temporal observations we will better understand the interactions between the surface of Mars and external forces, including the atmosphere. MUTED is available for the planetary scientific community via the webpage of the Institut für Planetologie (IfP) Muenster.

  3. Using Urban Landscape Trajectories to Develop a Multi-Temporal Land Cover Database to Support Ecological Modeling

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    Marina Alberti

    2009-12-01

    Full Text Available Urbanization and the resulting changes in land cover have myriad impacts on ecological systems. Monitoring these changes across large spatial extents and long time spans requires synoptic remotely sensed data with an appropriate temporal sequence. We developed a multi-temporal land cover dataset for a six-county area surrounding the Seattle, Washington State, USA, metropolitan region. Land cover maps for 1986, 1991, 1995, 1999, and 2002 were developed from Landsat TM images through a combination of spectral unmixing, image segmentation, multi-season imagery, and supervised classification approaches to differentiate an initial nine land cover classes. We then used ancillary GIS layers and temporal information to define trajectories of land cover change through multiple updating and backdating rules and refined our land cover classification for each date into 14 classes. We compared the accuracy of the initial approach with the landscape trajectory modifications and determined that the use of landscape trajectory rules increased our ability to differentiate several classes including bare soil (separated into cleared for development, agriculture, and clearcut forest and three intensities of urban. Using the temporal dataset, we found that between 1986 and 2002, urban land cover increased from 8 to 18% of our study area, while lowland deciduous and mixed forests decreased from 21 to 14%, and grass and agriculture decreased from 11 to 8%. The intensity of urban land cover increased with 252 km2 in Heavy Urban in 1986 increasing to 629 km2 by 2002. The ecological systems that are present in this region were likely significantly altered by these changes in land cover. Our results suggest that multi-temporal (i.e., multiple years and multiple seasons within years Landsat data are an economical means to quantify land cover and land cover change across large and highly heterogeneous urbanizing landscapes. Our data, and similar temporal land cover change

  4. CADASTRAL DATABASE POSITIONAL ACCURACY IMPROVEMENT

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    N. M. Hashim

    2017-10-01

    Full Text Available Positional Accuracy Improvement (PAI is the refining process of the geometry feature in a geospatial dataset to improve its actual position. This actual position relates to the absolute position in specific coordinate system and the relation to the neighborhood features. With the growth of spatial based technology especially Geographical Information System (GIS and Global Navigation Satellite System (GNSS, the PAI campaign is inevitable especially to the legacy cadastral database. Integration of legacy dataset and higher accuracy dataset like GNSS observation is a potential solution for improving the legacy dataset. However, by merely integrating both datasets will lead to a distortion of the relative geometry. The improved dataset should be further treated to minimize inherent errors and fitting to the new accurate dataset. The main focus of this study is to describe a method of angular based Least Square Adjustment (LSA for PAI process of legacy dataset. The existing high accuracy dataset known as National Digital Cadastral Database (NDCDB is then used as bench mark to validate the results. It was found that the propose technique is highly possible for positional accuracy improvement of legacy spatial datasets.

  5. Curation accuracy of model organism databases.

    Science.gov (United States)

    Keseler, Ingrid M; Skrzypek, Marek; Weerasinghe, Deepika; Chen, Albert Y; Fulcher, Carol; Li, Gene-Wei; Lemmer, Kimberly C; Mladinich, Katherine M; Chow, Edmond D; Sherlock, Gavin; Karp, Peter D

    2014-01-01

    Manual extraction of information from the biomedical literature-or biocuration-is the central methodology used to construct many biological databases. For example, the UniProt protein database, the EcoCyc Escherichia coli database and the Candida Genome Database (CGD) are all based on biocuration. Biological databases are used extensively by life science researchers, as online encyclopedias, as aids in the interpretation of new experimental data and as golden standards for the development of new bioinformatics algorithms. Although manual curation has been assumed to be highly accurate, we are aware of only one previous study of biocuration accuracy. We assessed the accuracy of EcoCyc and CGD by manually selecting curated assertions within randomly chosen EcoCyc and CGD gene pages and by then validating that the data found in the referenced publications supported those assertions. A database assertion is considered to be in error if that assertion could not be found in the publication cited for that assertion. We identified 10 errors in the 633 facts that we validated across the two databases, for an overall error rate of 1.58%, and individual error rates of 1.82% for CGD and 1.40% for EcoCyc. These data suggest that manual curation of the experimental literature by Ph.D-level scientists is highly accurate. Database URL: http://ecocyc.org/, http://www.candidagenome.org//

  6. Harmonic regression based multi-temporal cloud filtering algorithm for Landsat 8

    Science.gov (United States)

    Joshi, P.

    2015-12-01

    Landsat data archive though rich is seen to have missing dates and periods owing to the weather irregularities and inconsistent coverage. The satellite images are further subject to cloud cover effects resulting in erroneous analysis and observations of ground features. In earlier studies the change detection algorithm using statistical control charts on harmonic residuals of multi-temporal Landsat 5 data have been shown to detect few prominent remnant clouds [Brooks, Evan B., et al, 2014]. So, in this work we build on this harmonic regression approach to detect and filter clouds using a multi-temporal series of Landsat 8 images. Firstly, we compute the harmonic coefficients using the fitting models on annual training data. This time series of residuals is further subjected to Shewhart X-bar control charts which signal the deviations of cloud points from the fitted multi-temporal fourier curve. For the process with standard deviation σ we found the second and third order harmonic regression with a x-bar chart control limit [Lσ] ranging between [0.5σ HOT), and utilizing the seasonal physical properties of these parameters, we have designed a novel multi-temporal algorithm for filtering clouds from Landsat 8 images. The method is applied to Virginia and Alabama in Landsat8 UTM zones 17 and 16 respectively. Our algorithm efficiently filters all types of cloud cover with an overall accuracy greater than 90%. As a result of the multi-temporal operation and the ability to recreate the multi-temporal database of images using only the coefficients of the fourier regression, our algorithm is largely storage and time efficient. The results show a good potential for this multi-temporal approach for cloud detection as a timely and targeted solution for the Landsat 8 research community, catering to the need for innovative processing solutions in the infant stage of the satellite.

  7. Influence of multi-source and multi-temporal remotely sensed and ancillary data on the accuracy of random forest classification of wetlands in northern Minnesota

    Science.gov (United States)

    Corcoran, Jennifer M.; Knight, Joseph F.; Gallant, Alisa L.

    2013-01-01

    Wetland mapping at the landscape scale using remotely sensed data requires both affordable data and an efficient accurate classification method. Random forest classification offers several advantages over traditional land cover classification techniques, including a bootstrapping technique to generate robust estimations of outliers in the training data, as well as the capability of measuring classification confidence. Though the random forest classifier can generate complex decision trees with a multitude of input data and still not run a high risk of over fitting, there is a great need to reduce computational and operational costs by including only key input data sets without sacrificing a significant level of accuracy. Our main questions for this study site in Northern Minnesota were: (1) how does classification accuracy and confidence of mapping wetlands compare using different remote sensing platforms and sets of input data; (2) what are the key input variables for accurate differentiation of upland, water, and wetlands, including wetland type; and (3) which datasets and seasonal imagery yield the best accuracy for wetland classification. Our results show the key input variables include terrain (elevation and curvature) and soils descriptors (hydric), along with an assortment of remotely sensed data collected in the spring (satellite visible, near infrared, and thermal bands; satellite normalized vegetation index and Tasseled Cap greenness and wetness; and horizontal-horizontal (HH) and horizontal-vertical (HV) polarization using L-band satellite radar). We undertook this exploratory analysis to inform decisions by natural resource managers charged with monitoring wetland ecosystems and to aid in designing a system for consistent operational mapping of wetlands across landscapes similar to those found in Northern Minnesota.

  8. Multi-temporal topographic models in fluvial systems: are accuracies enough to change the temporal and spatial scales of our studies?

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    Vericat, Damià; Ramos, Ester; Brasington, James; Muñoz, Efrén; Béjar, María; Gibbins, Chris; Batalla, Ramon J.; Tena, Álvaro; Smith, Mark; Wheaton, Joe

    2015-04-01

    Recent advances in topography are offering a set of opportunities that deserve a critical evaluation before being successfully applied. Terrestrial Laser Scanning opened a new world by offering the opportunity to obtain topographic models at unprecedented resolutions. The time involved in data acquisition, although has substantially improved by means of fast scanners and new mobile platforms, limited the spatial and temporal scales in which such technique could be applied. Automatic Digital Photogrammetry or Structure from Motion is now offering a new set of opportunities and challenges. This technique possesses the trilogy a geomorphologist is looking to fully understand how landforms change and which are the main causes and consequences: speed, cost and resolution. But, a set of questions arise after all post-processing involved in these novel datasets: are accuracies enough to jump at large spatial scales? Can we repeat topographic surveys and depict small magnitude but relatively high frequent landform deformations overcoming the minimum level of detection of our comparisons? In this paper we present some of the preliminary results obtained in the background of MorphSed (www.morphsed.es). Morphsed is analysing the morpho-sedimentary dynamics of a fluvial system at multiple temporal scales. Multi-event topographic models (DEMs) are obtained by means of Structure from Motion using close range aerial photography obtained in a 12-km channel reach of the wandering Upper River Cinca (Southern Pyrenees, Iberian Peninsula). Topographic channel changes are critically analysed based on the quality of the developed models. DEMs obtained at different periods are compared (DoD). Two general comparisons are performed: (a) comparison of topographic models obtained before and after low magnitude channel changes, and (b) comparison of models acquired before and after major channel disturbances. Special attention is paid to the role of the ground control, data density and

  9. Multi-Temporal Landsat Images and Ancillary Data for Land Use/Cover Change (LULCC Detection in the Southwest of Burkina Faso, West Africa

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    Benewinde J-B. Zoungrana

    2015-09-01

    Full Text Available Accurate quantification of land use/cover change (LULCC is important for efficient environmental management, especially in regions that are extremely affected by climate variability and continuous population growth such as West Africa. In this context, accurate LULC classification and statistically sound change area estimates are essential for a better understanding of LULCC processes. This study aimed at comparing mono-temporal and multi-temporal LULC classifications as well as their combination with ancillary data and to determine LULCC across the heterogeneous landscape of southwest Burkina Faso using accurate classification results. Landsat data (1999, 2006 and 2011 and ancillary data served as input features for the random forest classifier algorithm. Five LULC classes were identified: woodland, mixed vegetation, bare surface, water and agricultural area. A reference database was established using different sources including high-resolution images, aerial photo and field data. LULCC and LULC classification accuracies, area and area uncertainty were computed based on the method of adjusted error matrices. The results revealed that multi-temporal classification significantly outperformed those solely based on mono-temporal data in the study area. However, combining mono-temporal imagery and ancillary data for LULC classification had the same accuracy level as multi-temporal classification which is an indication that this combination is an efficient alternative to multi-temporal classification in the study region, where cloud free images are rare. The LULCC map obtained had an overall accuracy of 92%. Natural vegetation loss was estimated to be 17.9% ± 2.5% between 1999 and 2011. The study area experienced an increase in agricultural area and bare surface at the expense of woodland and mixed vegetation, which attests to the ongoing deforestation. These results can serve as means of regional and global land cover products validation, as they

  10. MULTI-TEMPORAL ANALYSIS OF LANDSCAPES AND URBAN AREAS

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    E. Nocerino

    2012-07-01

    Full Text Available This article presents a 4D modelling approach that employs multi-temporal and historical aerial images to derive spatio-temporal information for scenes and landscapes. Such imagery represent a unique data source, which combined with photo interpretation and reality-based 3D reconstruction techniques, can offer a more complete modelling procedure because it adds the fourth dimension of time to 3D geometrical representation and thus, allows urban planners, historians, and others to identify, describe, and analyse changes in individual scenes and buildings as well as across landscapes. Particularly important to this approach are historical aerial photos, which provide data about the past that can be collected, processed, and then integrated as a database. The proposed methodology employs both historical (1945 and more recent (1973 and 2000s aerial images from the Trentino region in North-eastern Italy in order to create a multi-temporal database of information to assist researchers in many disciplines such as topographic mapping, geology, geography, architecture, and archaeology as they work to reconstruct building phases and to understand landscape transformations (Fig. 1.

  11. Accuracy of Veterans Affairs Databases for Diagnoses of Chronic Diseases

    OpenAIRE

    Singh, Jasvinder A.

    2009-01-01

    Introduction Epidemiologic studies usually use database diagnoses or patient self-report to identify disease cohorts, but no previous research has examined the extent to which self-report of chronic disease agrees with database diagnoses in a Veterans Affairs (VA) health care setting. Methods All veterans who had a medical care visit from October 1, 1996, through May 31, 1998, at any of the Veterans Integrated Service Network 13 facilities were surveyed about physician diagnosis of chronic ob...

  12. Study on interferometric combination for multi-temporal InSAR optimization

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    Wang, Xu; Wang, Yanbing; Li, Xiaojuan; Chen, Yahui; Chen, Xin; Hong, Wei

    2014-11-01

    Differential synthetic aperture radar interferometry (InSAR) has already proven its potential for ground subsidence monitoring. In recent years Multi-Temporal InSAR technology has been rapid development. Coherence of interferogram is an important indicator to measure the interferometric phase in the Multi-Temporal InSAR system. This paper study the effect of the Spatial-Temporal baseline on coherence for SAR images in Multi-Temporal InSAR processing base on the aspect of statistics. on the basis of a large amount of data, a formula for calculating coherence for SAR images was deduced which it correspond to the relationship between Spatial-Temporal baseline and the coherence of interferogram. This formula can optimize the selection of interference image pairs during processing Multi-Temporal InSAR. To determine whether this formula is useful, two methods of interference image pairs selection was used, one is the formula to optimize the selection, another is the traditional fixed threshold method. The author compared the coherence of Interferogram to judge the merits of the two methods. The results indicate that the formula not only select more interferogram from interferogram stack, but also increase the number of highly coherent points. And use SBAS-InSAR technique to obtain the 2010-2013 Beijing urban land subsidence information, verification monitoring accuracy by comparing level monitoring result.

  13. Improving data accuracy of commercial food outlet databases.

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    Ohri-Vachaspati, Punam; Martinez, Diane; Yedidia, Michael J; Petlick, Nirvana

    2011-01-01

    PURPOSE. Assessing food environments often requires using commercially available data. Disparate methods used for classifying food outlets in these databases call for creating a classification approach using common definitions. A systematic strategy for reclassifying food stores and restaurants, as they appear in commercial databases, into categories that differentiate the availability of healthy options is described here. DESIGN AND SETTING. Commercially available data on food outlets including names, addresses, North American Industry Classification System codes, and associated characteristics was obtained for five New Jersey communities. ANALYSIS. A reclassification methodology was developed using criteria and definitions from the literature to categorize food outlets based on availability of healthy options. Information in the database was supplemented by systematic Internet and key word searches, and from phone calls to food outlets. RESULTS. The methodology resulted in 622 supermarket/grocery stores, 183 convenience stores, and 148 specialty stores in the original data to be reclassified into 58 supermarkets, 30 grocery stores, 692 convenience stores, and 115 specialty stores. Outlets from the original list of 1485 full-service restaurants and 506 limited-service restaurants were reclassified as 563 full-service restaurants and 1247 limited-service restaurants. Reclassification resulted in less than one-seventh the number of supermarkets and grocery stores, more than three times the number of convenience stores, and twice as many limited-service restaurants-a much less healthy profile than the one generated by using exclusively the commercial databases. CONCLUSION. An explicit and replicable strategy is proposed for reclassifying food outlets in commercial databases into categories that differentiate on the basis of healthy food availability. The intent is to contribute towards building a consensus among researchers on definitions used in public health

  14. AUTOMATIC URBAN ILLEGAL BUILDING DETECTION USING MULTI-TEMPORAL SATELLITE IMAGES AND GEOSPATIAL INFORMATION SYSTEMS

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    N. Khalili Moghadam

    2015-12-01

    Full Text Available With the unprecedented growth of urban population and urban development, we are faced with the growing trend of illegal building (IB construction. Field visit, as the currently used method of IB detection, is time and man power consuming, in addition to its high cost. Therefore, an automatic IB detection is required. Acquiring multi-temporal satellite images and using image processing techniques for automatic change detection is one of the optimum methods which can be used in IB monitoring. In this research an automatic method of IB detection has been proposed. Two-temporal panchromatic satellite images of IRS-P5 of the study area in a part of Tehran, the city map and an updated spatial database of existing buildings were used to detect the suspected IBs. In the pre-processing step, the images were geometrically and radiometrically corrected. In the next step, the changed pixels were detected using K-means clustering technique because of its quickness and less user’s intervention required. Then, all the changed pixels of each building were identified and the change percentage of each building with the standard threshold of changes was compared to detect the buildings which are under construction. Finally, the IBs were detected by checking the municipality database. The unmatched constructed buildings with municipal database will be field checked to identify the IBs. The results show that out of 343 buildings appeared in the images; only 19 buildings were detected as under construction and three of them as unlicensed buildings. Furthermore, the overall accuracies of 83%, 79% and 75% were obtained for K-means change detection, detection of under construction buildings and IBs detection, respectively.

  15. Crop classification using multi-temporal HJ satellite images: case study in Kashgar, Xinjiang

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    Hao, Pengyu; Niu, Zheng; Wang, Li

    2014-11-01

    The HJ satellite constellation, characterized as high temporal resolution (4 day revisit frequency), has high potential to obtain cloud-free images covering all cruel periods for crop classification during growing season. In this paper, three HJ images (in May, July and September) were acquired, the performances of different multi-spectral HJ CCD data combinations for crop classification in Kashgar, Xinjiang were estimated using library for Support Vector Machine (LIBSVM), and ground reference data obtained in 2011 field work were used as training and validation samples. The result showed that multi-temporal HJ data has a potential to classify crops with an overall classification accuracy of 93.77%. Among the three time periods utilized in this research, the image acquired in July achieved the highest overall accuracy (86.98%) because all summer crops were under dense canopy closure. Cotton could be accurately extracted in May image (both user and produce accuracy are above 90%) because of its lower canopy closure compared with spring, the rotate crop (wheat_maize) and winter crop (wheat) at the time period. Then, the July and September combination performed as good as that of all threetime- period combination, which indicated that images obtained at cruel time periods are enough to identify crops, and the additional images improve little on classification accuracy. In addition, multi-temporal NDVI in cruel time periods of the growing season is testified efficient to classify crops with significant phenonlogical variances since they achieved similar overall accuracy to that of multi-temporal multi-spectral combination.

  16. Thematic Accuracy Assessment of the 2011 National Land Cover Database (NLCD)

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    Accuracy assessment is a standard protocol of National Land Cover Database (NLCD) mapping. Here we report agreement statistics between map and reference labels for NLCD 2011, which includes land cover for ca. 2001, ca. 2006, and ca. 2011. The two main objectives were assessment o...

  17. Auditing an Online Self-reported Interventional Radiology Adverse Event Database for Compliance and Accuracy.

    Science.gov (United States)

    Burch, Ezra A; Shyn, Paul B; Chick, Jeffrey F; Chauhan, Nikunj R

    2017-04-01

    The purpose of this study was to determine whether auditing an online self-reported interventional radiology quality assurance database improves compliance with record entry or improves the accuracy of adverse event (AE) reporting and grading. Physicians were trained in using the database before the study began. An audit of all database entries for the first 3 months, or the first quarter, was performed, at which point physicians were informed of the audit process; entries for the subsequent 3 months, or the second quarter, were again audited. Results between quarters were compared. Compliance with record entry improved from the first to second quarter, but reminders were necessary to ensure 100% compliance with record entry. Knowledge of the audit process did not significantly improve self-reporting of AE or accuracy of AE grading. However, auditing significantly changed the final AE reporting rates and grades. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. MODIS multi-temporal data retrieval and processing toolbox

    NARCIS (Netherlands)

    Mattiuzzi, M.; Verbesselt, J.; Klisch, A.

    2012-01-01

    The package functionalities are focused for the download and processing of multi-temporal datasets from MODIS sensors. All standard MODIS grid data can be accessed and processed by the package routines. The package is still in alpha development and not all the functionalities are available for now.

  19. Capability Database of Injection Molding Process— Requirements Study for Wider Suitability and Higher Accuracy

    DEFF Research Database (Denmark)

    Boorla, Srinivasa Murthy; Eifler, Tobias; Jepsen, Jens Dines O.

    2017-01-01

    Generally, there is little disagreement that an early consideration of dimensional accuracies achieved in production is conducive to the success of development of injection molding products. While different process capability databases (PCDBs) provide guidance for a meaningful estimation...... for an improved applicability of corresponding database solutions in an industrial context. A survey of database users at all phases of product value chain in the plastic industry revealed that 59% of the participating companies use their own, internally created databases, although reported to be not fully...... of the expected part variation, the adoption of corresponding guidelines and (proprietary) software tools seems to be, however, limited in industrial practice so far. This research paper addresses the gap between the available PCDBs and the requirement of designers in practice and investigates the key drivers...

  20. Thematic accuracy assessment of the 2011 National Land Cover Database (NLCD)

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    Wickham, James; Stehman, Stephen V.; Gass, Leila; Dewitz, Jon; Sorenson, Daniel G.; Granneman, Brian J.; Poss, Richard V.; Baer, Lori Anne

    2017-01-01

    Accuracy assessment is a standard protocol of National Land Cover Database (NLCD) mapping. Here we report agreement statistics between map and reference labels for NLCD 2011, which includes land cover for ca. 2001, ca. 2006, and ca. 2011. The two main objectives were assessment of agreement between map and reference labels for the three, single-date NLCD land cover products at Level II and Level I of the classification hierarchy, and agreement for 17 land cover change reporting themes based on Level I classes (e.g., forest loss; forest gain; forest, no change) for three change periods (2001–2006, 2006–2011, and 2001–2011). The single-date overall accuracies were 82%, 83%, and 83% at Level II and 88%, 89%, and 89% at Level I for 2011, 2006, and 2001, respectively. Many class-specific user's accuracies met or exceeded a previously established nominal accuracy benchmark of 85%. Overall accuracies for 2006 and 2001 land cover components of NLCD 2011 were approximately 4% higher (at Level II and Level I) than the overall accuracies for the same components of NLCD 2006. The high Level I overall, user's, and producer's accuracies for the single-date eras in NLCD 2011 did not translate into high class-specific user's and producer's accuracies for many of the 17 change reporting themes. User's accuracies were high for the no change reporting themes, commonly exceeding 85%, but were typically much lower for the reporting themes that represented change. Only forest loss, forest gain, and urban gain had user's accuracies that exceeded 70%. Lower user's accuracies for the other change reporting themes may be attributable to the difficulty in determining the context of grass (e.g., open urban, grassland, agriculture) and between the components of the forest-shrubland-grassland gradient at either the mapping phase, reference label assignment phase, or both. NLCD 2011 user's accuracies for forest loss, forest gain, and urban gain compare favorably with results from other

  1. Surface Subsidence Analysis by Multi-Temporal InSAR and GRACE: A Case Study in Beijing

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    Jiming Guo

    2016-09-01

    Full Text Available The aim of this study was to investigate the relationship between surface subsidence and groundwater changes. To investigate this relationship, we first analyzed surface subsidence. This paper presents the results of a case study of surface subsidence in Beijing from 1 August 2007 to 29 September 2010. The Multi-temporal Interferometric Synthetic Aperture Radar (multi-temporal InSAR technique, which can simultaneously detect point-like stable reflectors (PSs and distributed scatterers (DSs, was used to retrieve the subsidence magnitude and distribution in Beijing using 18 ENVISAT ASAR images. The multi-temporal InSAR-derived subsidence was verified by leveling at an accuracy better than 5 mm/year. Based on the verified multi-temporal InSAR results, a prominent uneven subsidence was identified in Beijing. Specifically, most of the subsidence velocities in the downtown area were within 10 mm/year, and the largest subsidence was detected in Tongzhou, with velocities exceeding 140 mm/year. Furthermore, Gravity Recovery and Climate Experiment (GRACE data were used to derive the groundwater change series and trend. By comparison with the multi-temporal InSAR-derived subsidence results, the long-term decreasing trend between groundwater changes and surface subsidence showed a relatively high consistency, and a significant impact of groundwater changes on the surface subsidence was identified. Additionally, the spatial distribution of the subsidence funnel was partially consistent with that of groundwater depression, i.e., the former possessed a wider range than the latter. Finally, the relationship between surface subsidence and groundwater changes was determined.

  2. Cloud and Cloud Shadow Masking Using Multi-Temporal Cloud Masking Algorithm in Tropical Environmental

    Science.gov (United States)

    Candra, D. S.; Phinn, S.; Scarth, P.

    2016-06-01

    A cloud masking approach based on multi-temporal satellite images is proposed. The basic idea of this approach is to detect cloud and cloud shadow by using the difference reflectance values between clear pixels and cloud and cloud shadow contaminated pixels. Several bands of satellite image which have big difference values are selected for developing Multi-temporal Cloud Masking (MCM) algorithm. Some experimental analyses are conducted by using Landsat-8 images. Band 3 and band 4 are selected because they can distinguish between cloud and non cloud. Afterwards, band 5 and band 6 are used to distinguish between cloud shadow and clear. The results show that the MCM algorithm can detect cloud and cloud shadow appropriately. Moreover, qualitative and quantitative assessments are conducted using visual inspections and confusion matrix, respectively, to evaluate the reliability of this algorithm. Comparison between this algorithm and QA band are conducted to prove the reliability of the approach. The results show that MCM better than QA band and the accuracy of the results are very high.

  3. Mapping paddy rice distribution using multi-temporal Landsat imagery in the Sanjiang Plain, northeast China

    Institute of Scientific and Technical Information of China (English)

    Cui JIN; Xiangming XIAO; Jinwei DONG; Yuanwei QIN; Zongming WANG

    2016-01-01

    Information of paddy rice distribution is essential for food production and methane emission calculation.Phenology-based algorithms have been utilized in the mapping of paddy rice fields by identifying the unique flooding and seedling transplanting phases using multi-temporal moderate resolution (500m to 1 km) images.In this study,we developed simple algorithms to identify paddy rice at a fine resolution at the regional scale using multi-temporal Landsat imagery.Sixteen Landsat images from 2010-2012 were used to generate the 30 m paddy rice map in the Sanjiang Plain,northeast China—one of the major paddy rice cultivation regions in China.Three vegetation indices,Normalized Difference Vegetation Index (NDVI),Enhanced Vegetation Index (EVI),and Land Surface Water Index (LSWI),were used to identify rice fields during the flooding/transplanting and ripening phases.The user and producer accuracies of paddy rice on the resultant Landsat-based paddy rice map were 90% and 94%,respectively.The Landsat-based paddy rice map was an improvement over the paddy rice layer on the National Land Cover Dataset,which was generated through visual interpretation and digitalization on the fine-resolution images.The agricultural census data substantially underreported paddy rice area,raising serious concern about its use for studies on food security.

  4. Thematic accuracy of the National Land Cover Database (NLCD) 2001 land cover for Alaska

    Science.gov (United States)

    Selkowitz, D.J.; Stehman, S.V.

    2011-01-01

    The National Land Cover Database (NLCD) 2001 Alaska land cover classification is the first 30-m resolution land cover product available covering the entire state of Alaska. The accuracy assessment of the NLCD 2001 Alaska land cover classification employed a geographically stratified three-stage sampling design to select the reference sample of pixels. Reference land cover class labels were determined via fixed wing aircraft, as the high resolution imagery used for determining the reference land cover classification in the conterminous U.S. was not available for most of Alaska. Overall thematic accuracy for the Alaska NLCD was 76.2% (s.e. 2.8%) at Level II (12 classes evaluated) and 83.9% (s.e. 2.1%) at Level I (6 classes evaluated) when agreement was defined as a match between the map class and either the primary or alternate reference class label. When agreement was defined as a match between the map class and primary reference label only, overall accuracy was 59.4% at Level II and 69.3% at Level I. The majority of classification errors occurred at Level I of the classification hierarchy (i.e., misclassifications were generally to a different Level I class, not to a Level II class within the same Level I class). Classification accuracy was higher for more abundant land cover classes and for pixels located in the interior of homogeneous land cover patches. ?? 2011.

  5. Enhanced diagnostic accuracy for quantitative bone scan using an artificial neural network system: a Japanese multi-center database project

    National Research Council Canada - National Science Library

    Nakajima, Kenichi; Nakajima, Yasuo; Horikoshi, Hiroyuki; Ueno, Munehisa; Wakabayashi, Hiroshi; Shiga, Tohru; Yoshimura, Mana; Ohtake, Eiji; Sugawara, Yoshifumi; Matsuyama, Hideyasu; Edenbrandt, Lars

    2013-01-01

    Artificial neural network (ANN)-based bone scan index (BSI), a marker of the amount of bone metastasis, has been shown to enhance diagnostic accuracy and reproducibility but is potentially affected by training database...

  6. Classification of paddy rice through multi-temporal multi-sensor data fusion

    Science.gov (United States)

    Im, Jungho; Park, Seonyoung

    2017-04-01

    Rice is one of important food resources in the world and its consumption continues to increase with increasing world population. Accurate paddy rice mapping and monitoring are crucial for food security and agricultural mitigation because they enable us to forecast rice production. There have been studies for paddy rice classification using optical sensor data. However, optical sensor data has a limitation for data acquisition due to cloud contamination. Active Synthetic Aperture Radar (SAR) data have been used to complement the cloud problems of optical sensor images. Integration of the multispectral and SAR data can produce the more reliable crop classification results than from a single sensor data. In addition, as paddy rice has distinct phenology, many studies used phenology features from multi-temporal data for detecting paddy rice. Thus, this study aims at mapping paddy rice by expanding the spectral and temporal dimensions of data. In this study, we conducted paddy rice classification through fusion of multi-temporal optical sensor (Landsat) and SAR (RADARSAT-1 and ALSO PALSAR) data using two machine learning approaches—random forest (RF) and support vector machines (SVM) over two study sites (Dangjin-si in South Korea and Sutter County, California in the United States). This study examined six scenarios to identify the effect of the expansion of data dimension. Each scenario has a different combination of data sources and seasonal characteristics. We examined variable importance to identify which sensor data collected at which season are important to classify paddy rice. In addition, this study proposed a new index called Paddy rice Mapping Index (PMI) for effective paddy rice classification considering the spectral and temporal characteristics of paddy rice. Scenario 6 that uses optical sensor and SAR multi temporal data showed the highest overall accuracy (site 1: 98.67%; site 2: 93.87%) for paddy rice classification among six scenarios. Both machine

  7. Crop classification based on multi-temporal satellite remote sensing data for agro-advisory services

    Science.gov (United States)

    Karale, Yogita; Mohite, Jayant; Jagyasi, Bhushan

    2014-11-01

    In this paper, we envision the use of satellite images coupled with GIS to obtain location specific crop type information in order to disseminate crop specific advises to the farmers. In our ongoing mKRISHI R project, the accurate information about the field level crop type and acreage will help in the agro-advisory services and supply chain planning and management. The key contribution of this paper is the field level crop classification using multi temporal images of Landsat-8 acquired during November 2013 to April 2014. The study area chosen is Vani, Maharashtra, India, from where the field level ground truth information for various crops such as grape, wheat, onion, soybean, tomato, along with fodder and fallow fields has been collected using the mobile application. The ground truth information includes crop type, crop stage and GPS location for 104 farms in the study area with approximate area of 42 hectares. The seven multi-temporal images of the Landsat-8 were used to compute the vegetation indices namely: Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR) and Difference Vegetation Index (DVI) for the study area. The vegetation indices values of the pixels within a field were then averaged to obtain the field level vegetation indices. For each crop, binary classification has been carried out using the feed forward neural network operating on the field level vegetation indices. The classification accuracy for the individual crop was in the range of 74.5% to 97.5% and the overall classification accuracy was found to be 88.49%.

  8. Monitoring powdery mildew of winter wheat by using moderate resolution multi-temporal satellite imagery.

    Directory of Open Access Journals (Sweden)

    Jingcheng Zhang

    Full Text Available Powdery mildew is one of the most serious diseases that have a significant impact on the production of winter wheat. As an effective alternative to traditional sampling methods, remote sensing can be a useful tool in disease detection. This study attempted to use multi-temporal moderate resolution satellite-based data of surface reflectances in blue (B, green (G, red (R and near infrared (NIR bands from HJ-CCD (CCD sensor on Huanjing satellite to monitor disease at a regional scale. In a suburban area in Beijing, China, an extensive field campaign for disease intensity survey was conducted at key growth stages of winter wheat in 2010. Meanwhile, corresponding time series of HJ-CCD images were acquired over the study area. In this study, a number of single-stage and multi-stage spectral features, which were sensitive to powdery mildew, were selected by using an independent t-test. With the selected spectral features, four advanced methods: mahalanobis distance, maximum likelihood classifier, partial least square regression and mixture tuned matched filtering were tested and evaluated for their performances in disease mapping. The experimental results showed that all four algorithms could generate disease maps with a generally correct distribution pattern of powdery mildew at the grain filling stage (Zadoks 72. However, by comparing these disease maps with ground survey data (validation samples, all of the four algorithms also produced a variable degree of error in estimating the disease occurrence and severity. Further, we found that the integration of MTMF and PLSR algorithms could result in a significant accuracy improvement of identifying and determining the disease intensity (overall accuracy of 72% increased to 78% and kappa coefficient of 0.49 increased to 0.59. The experimental results also demonstrated that the multi-temporal satellite images have a great potential in crop diseases mapping at a regional scale.

  9. MULTI-TEMPORAL SAR INTERFEROMETRY FOR LANDSLIDE MONITORING

    Directory of Open Access Journals (Sweden)

    R. Dwivedi

    2016-06-01

    Full Text Available In the past few years, SAR Interferometry specially InSAR and D-InSAR were extensively used for deformation monitoring related applications. Due to temporal and spatial decorrelation in dense vegetated areas, effectiveness of InSAR and D-InSAR observations were always under scrutiny. Multi-temporal InSAR methods are developed in recent times to retrieve the deformation signal from pixels with different scattering characteristics. Presently, two classes of multi-temporal InSAR algorithms are available- Persistent Scatterer (PS and Small Baseline (SB methods. This paper discusses the Stanford Method for Persistent Scatterer (StaMPS based PS-InSAR and the Small Baselines Subset (SBAS techniques to estimate the surface deformation in Tehri dam reservoir region in Uttarkhand, India. Both PS-InSAR and SBAS approaches used sixteen ENVISAT ASAR C-Band images for generating single master and multiple master interferograms stack respectively and their StaMPS processing resulted in time series 1D-Line of Sight (LOS mean velocity maps which are indicative of deformation in terms of movement towards and away from the satellites. From 1D LOS velocity maps, localization of landslide is evident along the reservoir rim area which was also investigated in the previous studies. Both PS-InSAR and SBAS effectively extract measurement pixels in the study region, and the general results provided by both approaches show a similar deformation pattern along the Tehri reservoir region. Further, we conclude that StaMPS based PS-InSAR method performs better in terms of extracting more number of measurement pixels and in the estimation of mean Line of Sight (LOS velocity as compared to SBAS method. It is also proposed to take up a few major landslides area in Uttarakhand for slope stability assessment.

  10. Rice yield estimation with multi-temporal Radarsat-2 data

    Science.gov (United States)

    Chen, Chi-Farn; Son, Nguyen-Thanh; Chen, Cheng-Ru

    2015-04-01

    Rice is the most important food crop in Taiwan. Monitoring rice crop yield is thus crucial for agronomic planners to formulate successful strategies to address national food security and rice grain export issues. However, there is a real challenge for this monitoring purpose because the size of rice fields in Taiwan was generally small and fragmented, and the cropping calendar was also different from region to region. Thus, satellite-based estimation of rice crop yield requires the data that have sufficient spatial and temporal resolutions. This study aimed to develop models to estimate rice crop yield from multi-temporal Radarsat-2 data (5 m resolution). Data processing were carried out for the first rice cropping season from February to July in 2014 in the western part of Taiwan, consisting of four main steps: (1) constructing time-series backscattering coefficient data, (2) spatiotemporal noise filtering of the time-series data, (3) establishment of crop yield models using the time-series backscattering coefficients and in-situ measured yield data, and (4) model validation using field data and government's yield statistics. The results indicated that backscattering behavior varied from region to region due to changes in cultural practices and cropping calendars. The highest correlation coefficient (R2 > 0.8) was obtained at the ripening period. The robustness of the established models was evaluated by comparisons between the estimated yields and in-situ measured yield data showed satisfactory results, with the root mean squared error (RMSE) smaller than 10%. Such results were reaffirmed by the correlation analysis between the estimated yields and government's rice yield statistics (R2 > 0.8). This study demonstrates advantages of using multi-temporal Radarsat-2 backscattering data for estimating rice crop yields in Taiwan prior to the harvesting period, and thus the methods were proposed for rice yield monitoring in other regions.

  11. Multi-Temporal SAR Interferometry for Landslide Monitoring

    Science.gov (United States)

    Dwivedi, R.; Narayan, A. B.; Tiwari, A.; Dikshit, O.; Singh, A. K.

    2016-06-01

    In the past few years, SAR Interferometry specially InSAR and D-InSAR were extensively used for deformation monitoring related applications. Due to temporal and spatial decorrelation in dense vegetated areas, effectiveness of InSAR and D-InSAR observations were always under scrutiny. Multi-temporal InSAR methods are developed in recent times to retrieve the deformation signal from pixels with different scattering characteristics. Presently, two classes of multi-temporal InSAR algorithms are available- Persistent Scatterer (PS) and Small Baseline (SB) methods. This paper discusses the Stanford Method for Persistent Scatterer (StaMPS) based PS-InSAR and the Small Baselines Subset (SBAS) techniques to estimate the surface deformation in Tehri dam reservoir region in Uttarkhand, India. Both PS-InSAR and SBAS approaches used sixteen ENVISAT ASAR C-Band images for generating single master and multiple master interferograms stack respectively and their StaMPS processing resulted in time series 1D-Line of Sight (LOS) mean velocity maps which are indicative of deformation in terms of movement towards and away from the satellites. From 1D LOS velocity maps, localization of landslide is evident along the reservoir rim area which was also investigated in the previous studies. Both PS-InSAR and SBAS effectively extract measurement pixels in the study region, and the general results provided by both approaches show a similar deformation pattern along the Tehri reservoir region. Further, we conclude that StaMPS based PS-InSAR method performs better in terms of extracting more number of measurement pixels and in the estimation of mean Line of Sight (LOS) velocity as compared to SBAS method. It is also proposed to take up a few major landslides area in Uttarakhand for slope stability assessment.

  12. Environmental Change Detection Using Multi-Temporal SAR Imagery

    Science.gov (United States)

    Fazel, Mohammad A.; Homayouni, Saeid; Aghakarimi, Armin

    2013-04-01

    Monitoring of environmental phenomena in short-, mid- and long-term periods is the first step of any study or plan for natural resource management. As a result, detection and identification of the environmental changes became a main area of research for different applications. Remotely sensed data and especially Synthetic Aperture Radar (SAR) imagery thanks to its independence to weather conditions and sun illumination, and its spatial and temporal resolution ability is a valuable source of information for change detection analysis and provides reliable data for information extraction for various applications. In general, change detection methods are grouped into supervised and unsupervised methods. Supervised methods work based on multi-temporal land-cover mapping of satellite images. While, unsupervised techniques include the very simple idea of image differencing to more sophisticated statistical modeling of changes in images. Unsupervised methods because of their advantages are more important in many applications. In recent years, the use of kernel based methods in change detection applications became an interesting topic in remote sensing community. Kernel-based methods and machine learning algorithms are the unsupervised paradigms which introduced powerful tools to deal with nonlinear classification. In this paper, we have presented a fully unsupervised framework for detecting the Urmia Lake changes during 2007 to 2010. This method uses the kernel-based clustering technique. The kernel k-means algorithm separates the changes from no-change classes of speckle free images. This method is a non-linear algorithm which considers the contextual information. For this purpose, at first, difference maps are calculated from multi-temporal data. Then these maps are projected into a higher dimensional space by using kernel function. Finally an unsupervised k-means clustering algorithm is used to obtain change and no-change classes. The proposed methodology is applied to

  13. GIS based mapping of land cover changes utilizing multi-temporal remotely sensed image data in Lake Hawassa Watershed, Ethiopia.

    Science.gov (United States)

    Nigatu Wondrade; Dick, Øystein B; Tveite, Havard

    2014-03-01

    Classifying multi-temporal image data to produce thematic maps and quantify land cover changes is one of the most common applications of remote sensing. Mapping land cover changes at the regional level is essential for a wide range of applications including land use planning, decision making, land cover database generation, and as a source of information for sustainable management of natural resources. Land cover changes in Lake Hawassa Watershed, Southern Ethiopia, were investigated using Landsat MSS image data of 1973, and Landsat TM images of 1985, 1995, and 2011, covering a period of nearly four decades. Each image was partitioned in a GIS environment, and classified using an unsupervised algorithm followed by a supervised classification method. A hybrid approach was employed in order to reduce spectral confusion due to high variability of land cover. Classification of satellite image data was performed integrating field data, aerial photographs, topographical maps, medium resolution satellite image (SPOT 20 m), and visual image interpretation. The image data were classified into nine land cover types: water, built-up, cropland, woody vegetation, forest, grassland, swamp, bare land, and scrub. The overall accuracy of the LULC maps ranged from 82.5 to 85.0 %. The achieved accuracies were reasonable, and the observed classification errors were attributable to coarse spatial resolution and pixels containing a mixture of cover types. Land cover change statistics were extracted and tabulated using the ERDAS Imagine software. The results indicated an increase in built-up area, cropland, and bare land areas, and a reduction in the six other land cover classes. Predominant land cover is cropland changing from 43.6 % in 1973 to 56.4 % in 2011. A significant portion of land cover was converted into cropland. Woody vegetation and forest cover which occupied 21.0 and 10.3 % in 1973, respectively, diminished to 13.6 and 5.6 % in 2011. The change in water body was very

  14. Multi-Temporal Analysis of WWII Reconnaissance Photos

    Science.gov (United States)

    Meixner, P.; Eckstein, M.

    2016-06-01

    There are millions of aerial photographs from the period of the Second Wold War available in the Allied archives, obtained by aerial photo reconnaissance, covering most of today's European countries. They are spanning the time from 1938 until the end of the war and even beyond. Photo reconnaissance provided intelligence information for the Allied headquarters and accompanied the bombing offensive against the German homeland and the occupied territories. One of the initial principal targets in Bohemia were the synthetized fuel works STW AG (Sudetenländische Treibstoffwerke AG) in Zaluzi (formerly Maltheuren) near Most (formerly Brück), Czech Republic. The STW AG synthetized fuel plant was not only subject to bombing raids, but a subject to quite intensive photo reconnaissance, too - long before the start of the bombing campaign. With a multi-temporal analysis of the available imagery from international archives we will demonstrate the factory build-up during 1942 and 1943, the effects of the bombing raids in 1944 and the struggle to keep the plant working in the last year of the war. Furthermore we would like to show the impact the bombings have today, in form of potential unexploded ordnance in the adjacent area of the open cast mines.

  15. Multi-temporal airborne LIDAR-DEMs for glacier and permafrost mapping and monitoring

    Directory of Open Access Journals (Sweden)

    J. Abermann

    2009-07-01

    Full Text Available The proposed method presents a simple and robust way to derive glacier extent by using multi-temporal high-resolution DEMs (digital elevation models as a main data source. For glaciers that are not debris covered, we perform the glacier boundary delineation by analysing roughness differences between ice and its surroundings. A promising way to distinguish dead ice, debris-covered ice or permafrost from its rocky surroundings is shown by taking elevation changes from DEMs of different dates into consideration. In case data has a high spatial and temporal resolution a good representation of the extent of debris cover and thus the overall ice covered area can be given. We use examples to show how potentially ambiguous areas can be treated decisively by the additional qualitative analysis of aerial photographs. Problems and limitations are discussed in comparison with selected other remote sensing techniques and accuracies are quantified. For glaciers larger than 1 km2 an accuracy of ±1% of the glacier area could be assessed. The errors of smaller glaciers do not exceed ±5% of the glacier area.

  16. Determination of mangrove change in Matang Mangrove Forest using multi temporal satellite imageries

    Science.gov (United States)

    Ibrahim, N. A.; Mustapha, M. A.; Lihan, T.; Ghaffar, M. A.

    2013-11-01

    Mangrove protects shorelines from damaging storm and hurricane winds, waves, and floods. Mangroves also help prevent erosion by stabilizing sediments with their tangled root systems. They maintain water quality and clarity, filtering pollutants and trapping sediments originating from land. However, mangrove has been reported to be threatened by land conversion for other activities. In this study, land use and land cover changes in Matang Mangrove Forest during the past 18 years (1993 to 2011) were determined using multi-temporal satellite imageries by Landsat TM and RapidEye. In this study, classification of land use and land cover approach was performed using the maximum likelihood classifier (MCL) method along with vegetation index differencing (NDVI) technique. Data obtained was evaluated through Kappa coefficient calculation for accuracy and results revealed that the classification accuracy was 81.25% with Kappa Statistics of 0.78. The results indicated changes in mangrove forest area to water body with 2,490.6 ha, aquaculture with 890.7 ha, horticulture with 1,646.1 ha, palm oil areas with 1,959.2 ha, dry land forest with 2,906.7 ha and urban settlement area with 224.1 ha. Combinations of these approaches were useful for change detection and for indication of the nature of these changes.

  17. Rapid Damage Assessment by Means of Multi-Temporal SAR — A Comprehensive Review and Outlook to Sentinel-1

    Directory of Open Access Journals (Sweden)

    Simon Plank

    2014-05-01

    Full Text Available Fast crisis response after natural disasters, such as earthquakes and tropical storms, is necessary to support, for instance, rescue, humanitarian, and reconstruction operations in the crisis area. Therefore, rapid damage mapping after a disaster is crucial, i.e., to detect the affected area, including grade and type of damage. Thereby, satellite remote sensing plays a key role due to its fast response, wide field of view, and low cost. With the increasing availability of remote sensing data, numerous methods have been developed for damage assessment. This article gives a comprehensive review of these techniques focusing on multi-temporal SAR procedures for rapid damage assessment: interferometric coherence and intensity correlation. The review is divided into six parts: First, methods based on coherence; second, the ones using intensity correlation; and third, techniques using both methodologies combined to increase the accuracy of the damage assessment are reviewed. Next, studies using additional data (e.g., GIS and optical imagery to support the damage assessment and increase its accuracy are reported. Moreover, selected studies on post-event SAR damage assessment techniques and examples of other applications of the interferometric coherence are presented. Then, the preconditions for a successful worldwide application of multi-temporal SAR methods for damage assessment and the limitations of current SAR satellite missions are reported. Finally, an outlook to the Sentinel-1 SAR mission shows possible solutions of these limitations, enabling a worldwide applicability of the presented damage assessment methods.

  18. A COMPARISON STUDY OF DIFFERENT KERNEL FUNCTIONS FOR SVM-BASED CLASSIFICATION OF MULTI-TEMPORAL POLARIMETRY SAR DATA

    Directory of Open Access Journals (Sweden)

    B. Yekkehkhany

    2014-10-01

    Full Text Available In this paper, a framework is developed based on Support Vector Machines (SVM for crop classification using polarimetric features extracted from multi-temporal Synthetic Aperture Radar (SAR imageries. The multi-temporal integration of data not only improves the overall retrieval accuracy but also provides more reliable estimates with respect to single-date data. Several kernel functions are employed and compared in this study for mapping the input space to higher Hilbert dimension space. These kernel functions include linear, polynomials and Radial Based Function (RBF. The method is applied to several UAVSAR L-band SAR images acquired over an agricultural area near Winnipeg, Manitoba, Canada. In this research, the temporal alpha features of H/A/α decomposition method are used in classification. The experimental tests show an SVM classifier with RBF kernel for three dates of data increases the Overall Accuracy (OA to up to 3% in comparison to using linear kernel function, and up to 1% in comparison to a 3rd degree polynomial kernel function.

  19. Annual Corn Yield Estimation through Multi-temporal MODIS Data

    Science.gov (United States)

    Shao, Y.; Zheng, B.; Campbell, J. B.

    2013-12-01

    This research employed 13 years of the Moderate Resolution Imaging Spectroradiometer (MODIS) to estimate annual corn yield for the Midwest of the United States. The overall objective of this study was to examine if annual corn yield could be accurately predicted using MODIS time-series NDVI (Normalized Difference Vegetation Index) and ancillary data such monthly precipitation and temperature. MODIS-NDVI 16-Day composite images were acquired from the USGS EROS Data Center for calendar years 2000 to 2012. For the same time-period, county level corn yield statistics were obtained from the National Agricultural Statistics Service (NASS). The monthly precipitation and temperature measures were derived from Precipitation-Elevation Regressions on Independent Slopes Model (PRISM) climate data. A cropland mask was derived using 2006 National Land Cover Database. For each county and within the cropland mask, the MODIS-NDVI time-series data and PRISM climate data were spatially averaged, at their respective time steps. We developed a random forest predictive model with the MODIS-NDVI and climate data as predictors and corn yield as response. To assess the model accuracy, we used twelve years of data as training and the remaining year as hold-out testing set. The training and testing procedures were repeated 13 times. The R2 ranged from 0.72 to 0.83 for testing years. It was also found that the inclusion of climate data did not improve the model predictive performance. MODIS-NDVI time-series data alone might provide sufficient information for county level corn yield prediction.

  20. Towards Building Reliable, High-Accuracy Solar Irradiance Database For Arid Climates

    Science.gov (United States)

    Munawwar, S.; Ghedira, H.

    2012-12-01

    Middle East's growing interest in renewable energy has led to increased activity in solar technology development with the recent commissioning of several utility-scale solar power projects and many other commercial installations across the Arabian Peninsula. The region, lying in a virtually rainless sunny belt with a typical daily average solar radiation exceeding 6 kWh/m2, is also one of the most promising candidates for solar energy deployment. However, it is not the availability of resource, but its characterization and reasonably accurate assessment that determines the application potential. Solar irradiance, magnitude and variability inclusive, is the key input in assessing the economic feasibility of a solar system. The accuracy of such data is of critical importance for realistic on-site performance estimates. This contribution aims to identify the key stages in developing a robust solar database for desert climate by focusing on the challenges that an arid environment presents to parameterization of solar irradiance attenuating factors. Adjustments are proposed based on the currently available resource assessment tools to produce high quality data for assessing bankability. Establishing and maintaining ground solar irradiance measurements is an expensive affair and fairly limited in time (recently operational) and space (fewer sites) in the Gulf region. Developers within solar technology industry, therefore, rely on solar radiation models and satellite-derived data for prompt resource assessment needs. It is imperative that such estimation tools are as accurate as possible. While purely empirical models have been widely researched and validated in the Arabian Peninsula's solar modeling history, they are known to be intrinsically site-specific. A primal step to modeling is an in-depth understanding of the region's climate, identifying the key players attenuating radiation and their appropriate characterization to determine solar irradiance. Physical approach

  1. MULTI-TEMPORAL REMOTE SENSING IMAGE CLASSIFICATION - A MULTI-VIEW APPROACH

    Data.gov (United States)

    National Aeronautics and Space Administration — MULTI-TEMPORAL REMOTE SENSING IMAGE CLASSIFICATION - A MULTI-VIEW APPROACH VARUN CHANDOLA AND RANGA RAJU VATSAVAI Abstract. Multispectral remote sensing images have...

  2. Analysis of uncertainty in multi-temporal object-based classification

    Science.gov (United States)

    Löw, Fabian; Knöfel, Patrick; Conrad, Christopher

    2015-07-01

    Agricultural management increasingly uses crop maps based on classification of remotely sensed data. However, classification errors can translate to errors in model outputs, for instance agricultural production monitoring (yield, water demand) or crop acreage calculation. Hence, knowledge on the spatial variability of the classier performance is important information for the user. But this is not provided by traditional assessments of accuracy, which are based on the confusion matrix. In this study, classification uncertainty was analyzed, based on the support vector machines (SVM) algorithm. SVM was applied to multi-spectral time series data of RapidEye from different agricultural landscapes and years. Entropy was calculated as a measure of classification uncertainty, based on the per-object class membership estimations from the SVM algorithm. Permuting all possible combinations of available images allowed investigating the impact of the image acquisition frequency and timing, respectively, on the classification uncertainty. Results show that multi-temporal datasets decrease classification uncertainty for different crops compared to single data sets, but there was no "one-image-combination-fits-all" solution. The number and acquisition timing of the images, for which a decrease in uncertainty could be realized, proved to be specific to a given landscape, and for each crop they differed across different landscapes. For some crops, an increase of uncertainty was observed when increasing the quantity of images, even if classification accuracy was improved. Random forest regression was employed to investigate the impact of different explanatory variables on the observed spatial pattern of classification uncertainty. It was strongly influenced by factors related with the agricultural management and training sample density. Lower uncertainties were revealed for fields close to rivers or irrigation canals. This study demonstrates that classification uncertainty estimates

  3. Modeling spatial and temporal change of soil erosion based on multi-temporal remotely sensed data

    Institute of Scientific and Technical Information of China (English)

    Pei Liu; PeiJun Du; RuiMei Han; Chao Ma; YouFeng Zou

    2015-01-01

    In order to monitor the pattern, distribution, and trend of land use/cover change (LUCC) and its impacts on soil erosion, it is highly appropriate to adopt Remote Sensing (RS) data and Geographic Information System (GIS) to analyze, assess, simulate, and predict the spatial and temporal evolution dynamics. In this paper, multi-temporal Landsat TM/ETM+ re-motely sensed data are used to generate land cover maps by image classification, and the Cellular Automata Markov (CA_Markov) model is employed to simulate the evolution and trend of landscape pattern change. Furthermore, the Re-vised Universal Soil Loss Equation (RUSLE) is used to evaluate the situation of soil erosion in the case study mining area. The trend of soil erosion is analyzed according to total/average amount of soil erosion, and the rainfall (R), cover man-agement (C), and support practice (P) factors in RUSLE relevant to soil erosion are determined. The change trends of soil erosion and the relationship between land cover types and soil erosion amount are analyzed. The results demonstrate that the CA_Markov model is suitable to simulate and predict LUCC trends with good efficiency and accuracy, and RUSLE can calculate the total soil erosion effectively. In the study area, there was minimal erosion grade and this is expected to con-tinue to decline in the next few years, according to our prediction results.

  4. Mapping Plastic-Mulched Farmland with Multi-Temporal Landsat-8 Data

    Directory of Open Access Journals (Sweden)

    Hasituya

    2017-06-01

    Full Text Available Using plastic mulching for farmland is booming around the world. Despite its benefit of protecting crops from unfavorable conditions and increasing crop yield, the massive use of the plastic-mulching technique causes many environmental problems. Therefore, timely and effective mapping of plastic-mulched farmland (PMF is of great interest to policy-makers to leverage the trade-off between economic profit and adverse environmental impacts. However, it is still challenging to implement remote-sensing-based PMF mapping due to its changing spectral characteristics with the growing seasons of crops and geographic regions. In this study, we examined the potential of multi-temporal Landsat-8 imagery for mapping PMF. To this end, we gathered the information of spectra, textures, indices, and thermal features into random forest (RF and support vector machine (SVM algorithms in order to select the common characteristics for distinguishing PMF from other land cover types. The experiment was conducted in Jizhou, Hebei Province. The results demonstrated that the spectral features and indices features of NDVI (normalized difference vegetation index, GI (greenness index, and textural features of mean are more important than the other features for mapping PMF in Jizhou. With that, the optimal period for mapping PMF is in April, followed by May. A combination of these two times (April and May is better than later in the season. The highest overall, producer’s, and user’s accuracies achieved were 97.01%, 92.48%, and 96.40% in Jizhou, respectively.

  5. Californian demonstration and validation of automated agricultural field extraction from multi-temporal Landsat data

    Science.gov (United States)

    Yan, L.; Roy, D. P.

    2013-12-01

    The spatial distribution of agricultural fields is a fundamental description of rural landscapes and the location and extent of fields is important to establish the area of land utilized for agricultural yield prediction, resource allocation, and for economic planning. To date, field objects have not been extracted from satellite data over large areas because of computational constraints and because consistently processed appropriate resolution data have not been available or affordable. We present a fully automated computational methodology to extract agricultural fields from 30m Web Enabled Landsat data (WELD) time series and results for approximately 250,000 square kilometers (eleven 150 x 150 km WELD tiles) encompassing all the major agricultural areas of California. The extracted fields, including rectangular, circular, and irregularly shaped fields, are evaluated by comparison with manually interpreted Landsat field objects. Validation results are presented in terms of standard confusion matrix accuracy measures and also the degree of field object over-segmentation, under-segmentation, fragmentation and shape distortion. The apparent success of the presented field extraction methodology is due to several factors. First, the use of multi-temporal Landsat data, as opposed to single Landsat acquisitions, that enables crop rotations and inter-annual variability in the state of the vegetation to be accommodated for and provides more opportunities for cloud-free, non-missing and atmospherically uncontaminated surface observations. Second, the adoption of an object based approach, namely the variational region-based geometric active contour method that enables robust segmentation with only a small number of parameters and that requires no training data collection. Third, the use of a watershed algorithm to decompose connected segments belonging to multiple fields into coherent isolated field segments and a geometry based algorithm to detect and associate parts of

  6. Pan-Tropical Forest Mapping by Exploiting Textures of Multi-Temporal High Resolution SAR Data

    Science.gov (United States)

    Knuth, R.; Eckardt, R.; Richter, N.; Schmullius, C.

    2012-12-01

    radar images were processed using an operational processing chain that includes radiometric transformation, noise reduction, and georeferencing of the SAR data. In places with pronounced topography both satellites were used as single pass interferometer to derive a digital surface model in order to perform an orthorectification followed by a topographic normalization of the SAR backscatter values. As prescribed by the FAO, the final segment-based classification algorithm was fed by multi-temporal backscatter information, a set of textural features, and information on the degree of coherence between the multi-temporal acquisitions. Validation with available high resolution optical imagery suggests that the produced forest maps possess an overall accuracy of 75 percent or higher.

  7. Registration in the Danish Regional Nonmelanoma Skin Cancer Dermatology Database: completeness of registration and accuracy of key variables

    Directory of Open Access Journals (Sweden)

    Anna L Lamberg

    2010-05-01

    Full Text Available Anna L Lamberg1, Deirdre Cronin-Fenton2, Anne B Olesen11Department of Dermatology, 2Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, C, DenmarkObjective: To validate a clinical database for nonmelanoma skin cancer (NMSC with the aim of monitoring and predicting the prognosis of NMSC treated by dermatologists in clinics in the central and north Denmark regions.Methods: We assessed the completeness of registration of patients and follow-up visits, and positive predictive value (PPV, negative predictive value (NPV, sensitivity, and specificity of registrations in the database. We used the Danish Pathology Registry (DPR (n = 288 and a review of randomly selected medical records (n = 67 from two clinics as gold standards.Results: The completeness of registration of patients was 62% and 76% with DPR and medical record review as gold standards, respectively. The completeness of registration of 1st and 2nd follow up visits was 85% and 69%, respectively. The PPV and NPV ranged from 85% to 99%, and the sensitivity and specificity from 67% to 100%.Conclusion: Overall, the accuracy of variables registered in the NMSC database was satisfactory but completeness of patient registration and follow-up visits were modest. The NMSC database is a potentially valuable tool for monitoring and facilitating improvement of NMSC treatment in dermatology clinics. However, there is still room for improvement of registration of both patients and their follow-up visits.Keywords: nonmelanoma skin cancer, validation, database, positive predictive value, completeness

  8. A discussion on different techniques for GIS data collecting, precision, accuracy and quality of database

    OpenAIRE

    2004-01-01

    Nowadays, is a common sense the importance of geotechnologies in urban planning, transportation engineering and other different areas of knowledge. The Geographic Information System (GIS) is one of the geotechnologies that has been used increasingly. The collection of information and creation of a database are the most expensive, complex and important task in a GIS project. The collection of information results from the direct and indirect measurement of the real world. The reason for c...

  9. Databases

    Data.gov (United States)

    National Aeronautics and Space Administration — The databases of computational and experimental data from the first Aeroelastic Prediction Workshop are located here. The databases file names tell their contents by...

  10. Retrieval of interseismic displacement from multi-temporal InSAR measurements: challenges and solutions

    Science.gov (United States)

    Zhang, L.; Ding, X.; Lu, Z.; Wen, Y.; Hu, J.

    2016-12-01

    High-resolution measurements of interseismic displacement are critical for understanding the earthquake cycle and for assessing earthquake hazard. Compared with sparsely located GNSS sites, it is well-known that by jointly analyzing a set of data over the same area acquired on different dates, multi-temporal InSAR (MTInSAR) is capable of remotely imaging interseismic deformation at an unprecedented level of spatial resolution. However conventional MTInSAR cannot hold a considerate promise for the precise retrieval of interseismic deformation in tectonically active zones where complicated atmospheric delay, orbital errors, and localized seasonal ground fluctuations commonly exist. Of interest in this study is to develop reliable solutions to correct or suppress these unwanted signals thereby to improve the accuracy of mapped interseismic displacement. Our technical innovations lie in the following aspects. According to different spatial-temporal characteristics, a joint model that takes both orbit errors and interseismic displacement as parameters is designed to isolate long wavelength motion from orbit error even in the case these two types of signals exhibit similar spatial patterns. To suppress the localized impacts (e.g., a portion of atmospheric artifacts and small-scale anthropogenic deformation), spatial correlation is employed as a constraint during the parameter estimation. The proposed solutions are evaluated by synthetic tests and applied to map the interseismic displacement over Eastern Turkey that spans the Arabia-Eurasia plate boundary zone from a large set of radar images acquired by Envisat/ASAR and Sentinel-1. The derived interseismic displacement validated by GPS data is further used to invert the slip rate and locking depth for the North and East Anatolian Faults. A cross-comparison with published results is also conducted.

  11. Metabolomic database annotations via query of elemental compositions: Mass accuracy is insufficient even at less than 1 ppm

    Directory of Open Access Journals (Sweden)

    Fiehn Oliver

    2006-04-01

    Full Text Available Abstract Background Metabolomic studies are targeted at identifying and quantifying all metabolites in a given biological context. Among the tools used for metabolomic research, mass spectrometry is one of the most powerful tools. However, metabolomics by mass spectrometry always reveals a high number of unknown compounds which complicate in depth mechanistic or biochemical understanding. In principle, mass spectrometry can be utilized within strategies of de novo structure elucidation of small molecules, starting with the computation of the elemental composition of an unknown metabolite using accurate masses with errors Results High mass accuracy (95% of false candidates. This orthogonal filter can condense several thousand candidates down to only a small number of molecular formulas. Example calculations for 10, 5, 3, 1 and 0.1 ppm mass accuracy are given. Corresponding software scripts can be downloaded from http://fiehnlab.ucdavis.edu. A comparison of eight chemical databases revealed that PubChem and the Dictionary of Natural Products can be recommended for automatic queries using molecular formulae. Conclusion More than 1.6 million molecular formulae in the range 0–500 Da were generated in an exhaustive manner under strict observation of mathematical and chemical rules. Assuming that ion species are fully resolved (either by chromatography or by high resolution mass spectrometry, we conclude that a mass spectrometer capable of 3 ppm mass accuracy and 2% error for isotopic abundance patterns outperforms mass spectrometers with less than 1 ppm mass accuracy or even hypothetical mass spectrometers with 0.1 ppm mass accuracy that do not include isotope information in the calculation of molecular formulae.

  12. Databases

    Directory of Open Access Journals (Sweden)

    Nick Ryan

    2004-01-01

    Full Text Available Databases are deeply embedded in archaeology, underpinning and supporting many aspects of the subject. However, as well as providing a means for storing, retrieving and modifying data, databases themselves must be a result of a detailed analysis and design process. This article looks at this process, and shows how the characteristics of data models affect the process of database design and implementation. The impact of the Internet on the development of databases is examined, and the article concludes with a discussion of a range of issues associated with the recording and management of archaeological data.

  13. GRACE Data-based High Accuracy Global Static Earth's Gravity Field Model

    Directory of Open Access Journals (Sweden)

    CHEN Qiujie

    2016-04-01

    Full Text Available To recover the highly accurate static earth's gravity field by using GRACE satellite data is one of the hot topics in geodesy. Since linearization errors of dynamic approach quickly increase when extending satellite arc length, we established a modified dynamic approach for processing GRACE orbit and range-rate measurements in this paper, which treated orbit observations of the twin GRACE satellites as approximate values for linearization. Using the GRACE data spanning the period Jan. 2003 to Dec. 2010, containing satellite attitudes, orbits, range-rate, and non-conservative forces, we developed two global static gravity field models. One is the unconstrained solution called Tongji-Dyn01s complete to degree and order 180; the other one is the Tongji-Dyn01k model computed by using Kaula constraint. The comparisons between our models and those latest GRACE-only models (including the AIUB-GRACE03, the GGM05S, the ITSG-Grace2014k and the Tongji-GRACE01 published by different international groups, and the external validations with marine gravity anomalies from DTU13 product and height anomalies from GPS/levelling data, were performed in this study. The results demonstrate that the Tongji-Dyn01s has the same accuracy level with those of the latest GRACE-only models, while the Tongji-Dyn01k model is closer to the EIGEN6C2 than the other GRACE-only models as a whole.

  14. Multi-Temporal Multi-Sensor Analysis of Urbanization and Environmental/Climate Impact in China for Sustainable Urban Development

    Science.gov (United States)

    Ban, Yifang; Gong, Peng; Gamba, Paolo; Taubenbock, Hannes; Du, Peijun

    2016-08-01

    The overall objective of this research is to investigate multi-temporal, multi-scale, multi-sensor satellite data for analysis of urbanization and environmental/climate impact in China to support sustainable planning. Multi- temporal multi-scale SAR and optical data have been evaluated for urban information extraction using innovative methods and algorithms, including KTH- Pavia Urban Extractor, Pavia UEXT, and an "exclusion- inclusion" framework for urban extent extraction, and KTH-SEG, a novel object-based classification method for detailed urban land cover mapping. Various pixel- based and object-based change detection algorithms were also developed to extract urban changes. Several Chinese cities including Beijing, Shanghai and Guangzhou are selected as study areas. Spatio-temporal urbanization patterns and environmental impact at regional, metropolitan and city core were evaluated through ecosystem service, landscape metrics, spatial indices, and/or their combinations. The relationship between land surface temperature and land-cover classes was also analyzed.The urban extraction results showed that urban areas and small towns could be well extracted using multitemporal SAR data with the KTH-Pavia Urban Extractor and UEXT. The fusion of SAR data at multiple scales from multiple sensors was proven to improve urban extraction. For urban land cover mapping, the results show that the fusion of multitemporal SAR and optical data could produce detailed land cover maps with improved accuracy than that of SAR or optical data alone. Pixel-based and object-based change detection algorithms developed with the project were effective to extract urban changes. Comparing the urban land cover results from mulitemporal multisensor data, the environmental impact analysis indicates major losses for food supply, noise reduction, runoff mitigation, waste treatment and global climate regulation services through landscape structural changes in terms of decreases in service area, edge

  15. Infrastructure assessment for disaster management using multi-sensor and multi-temporal remote sensing imagery

    DEFF Research Database (Denmark)

    Butenuth, Matthias; Frey, Daniel; Nielsen, Allan Aasbjerg

    2011-01-01

    In this paper, a new assessment system is presented to evaluate infrastructure objects such as roads after natural disasters in near-realtime. A particular aim is the exploitation of multi-sensorial and multi-temporal imagery together with further {GIS-}data in a comprehensive assessment framework...

  16. Infrastructure assessment for disaster management using multi-sensor and multi-temporal remote sensing imagery

    DEFF Research Database (Denmark)

    Butenuth, Matthias; Frey, Daniel; Nielsen, Allan Aasbjerg

    2011-01-01

    In this paper, a new assessment system is presented to evaluate infrastructure objects such as roads after natural disasters in near-realtime. A particular aim is the exploitation of multi-sensorial and multi-temporal imagery together with further {GIS-}data in a comprehensive assessment framework...

  17. Geomorphological change detection using object-based feature extraction from multi-temporal LIDAR data

    NARCIS (Netherlands)

    Seijmonsbergen, A.C.; Anders, N.S.; Bouten, W.; Feitosa, R.Q.; da Costa, G.A.O.P.; de Almeida, C.M.; Fonseca, L.M.G.; Kux, H.J.H.

    2012-01-01

    Multi-temporal LiDAR DTMs are used for the development and testing of a method for geomorphological change analysis in western Austria. Our test area is located on a mountain slope in the Gargellen Valley in western Austria. Six geomorphological features were mapped by using stratified Object-Based

  18. Multi-Temporal Decomposed Wind and Load Power Models for Electric Energy Systems

    Science.gov (United States)

    Abdel-Karim, Noha

    electricity market rules capable of providing the right incentives to manage uncertainties and of differentiating various technologies according to the rate at which they can respond to ever changing conditions. Given the overall need for modeling uncertainties in electric energy systems, we consider in this thesis the problem of multi-temporal modeling of wind and demand power, in particular. Historic data is used to derive prediction models for several future time horizons. Short-term prediction models derived can be used for look-ahead economic dispatch and unit commitment, while the long-term annual predictive models can be used for investment planning. As expected, the accuracy of such predictive models depends on the time horizons over which the predictions are made, as well as on the nature of uncertain signals. It is shown that predictive models obtained using the same general modeling approaches result in different accuracy for wind than for demand power. In what follows, we introduce several models which have qualitatively different patterns, ranging from hourly to annual. We first transform historic time-stamped data into the Fourier Transform (Fr) representation. The frequency domain data representation is used to decompose the wind and load power signals and to derive predictive models relevant for short-term and long-term predictions using extracted spectral techniques. The short-term results are interpreted next as a Linear Prediction Coding Model (LPC) and its accuracy is analyzed. Next, a new Markov-Based Sensitivity Model (MBSM) for short term prediction has been proposed and the dispatched costs of uncertainties for different predictive models with comparisons have been developed. Moreover, the Discrete Markov Process (DMP) representation is applied to help assess probabilities of most likely short-, medium- and long-term states and the related multi-temporal risks. In addition, this thesis discusses operational impacts of wind power integration in

  19. PHOTOGRAMMETRIC EVALUATION OF MULTI-TEMPORAL FIXED WING UAV IMAGERY

    Directory of Open Access Journals (Sweden)

    E. Gülch

    2012-09-01

    Full Text Available Several flights have been undertaken with PAMS (Photogrammetric Aerial Mapping System by Germatics, Germany, which is briefly introduced. This system is based on the SmartPlane fixed-wing UAV and a CANON IXUS camera system. The plane is equipped with GPS and has an infrared sensor system to estimate attitude values. A software has been developed to link the PAMS output to a standard photogrammetric processing chain built on Trimble INPHO. The linking of the image files and image IDs and the handling of different cases with partly corrupted output have to be solved to generate an INPHO project file. Based on this project file the software packages MATCH-AT, MATCH-T DSM, OrthoMaster and OrthoVista for digital aerial triangulation, DTM/DSM generation and finally digital orthomosaik generation are applied. The focus has been on investigations on how to adapt the "usual" parameters for the digital aerial triangulation and other software to the UAV flight conditions, which are showing high overlaps, large kappa angles and a certain image blur in case of turbulences. It was found, that the selected parameter setup shows a quite stable behaviour and can be applied to other flights. Investigations have been performed to improve the image quality estimates by the PAMS software and extend it to whole images. This gives the user a reliable basis when deciding on rejecting images with low quality for the follow-up process. Flights over the same area at different times have been compared to each other. The major objective was first to see, on how far differences occur relative to each other, without having access to ground control data, which would have a potential for applications with low requirements on the absolute accuracy. In a second stage the results are compared to GPS measurements on the ground. The results show, that there are influences of weather and illumination visible. The "unusual" flight pattern, which shows big time differences for

  20. Comparison of Two Methods in Multi-Temporal Differential Interferometry: Application to the Measurement of Mexico City Subsidence

    Science.gov (United States)

    Yan, Y.; Doin, M. P.; Lopez-Quiroz, P.; Tupin, F.; Fruneau, B.; Trouve, E.; Pinel, V.

    2010-03-01

    In multi-temporal InSAR processing, both the Permanent Scatterer (PS) and Small BAseline Subset (SBAS) methods are optimized to obtain ground displacement rates with a nominal accuracy of millimetres per year. The PS approach extracts deformation signals on point targets by modelling and analyzing their phase value that remains stable in time for all interferograms performed with a common master image. The SBAS approach is developped to maximize the spatial and temporal coherence by construction of small baseline interferograms. In this paper, we evaluate the performance of both approaches, their limitations and their complementarity through an inter-comparison. We apply both the Gamma-IPTA chain (PS approach) and the SBAS approach developped by Lopez-Quiroz et al. on 38 ENVISAT images from November 2002 to March 2007 to map the Mexico City subsidence. The subsidence rate maps obtained by both approaches are compared quantitatively and analysed at different steps of the PS approach.The difference is partly explained by errors in the spatial integration of subsidence rates in the PS approach. At a local scale, outside subsiding area, the difference standard deviation drops to 0.9 mm/yr, close to the nominal accuracy of both approaches. On the other hand, within the subsiding area, it increases to 3.6 mm/yr, that may be partly interpreted as punctual differential subsidence between various human-made structures unseen by the SBAS approach.

  1. Object-Based Greenhouse Horticultural Crop Identification from Multi-Temporal Satellite Imagery: A Case Study in Almeria, Spain

    Directory of Open Access Journals (Sweden)

    Manuel A. Aguilar

    2015-06-01

    Full Text Available Greenhouse detection and mapping via remote sensing is a complex task, which has already been addressed in numerous studies. In this research, the innovative goal relies on the identification of greenhouse horticultural crops that were growing under plastic coverings on 30 September 2013. To this end, object-based image analysis (OBIA and a decision tree classifier (DT were applied to a set consisting of eight Landsat 8 OLI images collected from May to November 2013. Moreover, a single WorldView-2 satellite image acquired on 30 September 2013, was also used as a data source. In this approach, basic spectral information, textural features and several vegetation indices (VIs derived from Landsat 8 and WorldView-2 multi-temporal satellite data were computed on previously segmented image objects in order to identify four of the most popular autumn crops cultivated under greenhouse in Almería, Spain (i.e., tomato, pepper, cucumber and aubergine. The best classification accuracy (81.3% overall accuracy was achieved by using the full set of Landsat 8 time series. These results were considered good in the case of tomato and pepper crops, being significantly worse for cucumber and aubergine. These results were hardly improved by adding the information of the WorldView-2 image. The most important information for correct classification of different crops under greenhouses was related to the greenhouse management practices and not the spectral properties of the crops themselves.

  2. Multi-temporal image co-registration improvement for a better representation and quantification of risky situations: the Belvedere Glacier case study

    Directory of Open Access Journals (Sweden)

    Enrico Borgogno Mondino

    2015-07-01

    Full Text Available Scientific applications dealing with natural hazards make wide use of digital geographical data and change detection techniques. If the attention is focused on changes affecting surfaces’ geometry, multi-temporal aerial photogrammetry can represent an effective tool. In this case, the degree of spatial coherence between measurements at different times is an important issue to deal with. Reliability and accuracy of measured differences strictly depend on the strategy used during image processing. In this paper, a simultaneous multi-temporal aerial image bundle adjustment approach (MTBA is compared against two more traditional strategies for aerial stereo-pair adjustment to map surface changes of the Belvedere Glacier (Italian north-western Alps in the period 2001–2003. Two aerial stereo pairs (of 2001 and 2003 were used to generate the correspondent digital surface models. These were then compared to map glacier shape differences and calculate ablation and accumulation volumes. Results demonstrate that the proposed MTBA approach improves and maximizes accuracy and reliability of measured differences also when available reference data are low quality ones. Final uncertainty for both direct (surface height differences and derived (volume changes measurements were quantified and mapped.

  3. A Phenology-based Approach for Rice Crop Mapping from Multi-temporal Sentinel-1A Data in Taiwan

    Science.gov (United States)

    Chen, C. F.; Chen, J. B.; Nguyen, S. T.; Chen, C. R.; Chiang, S. H.

    2016-12-01

    Rice is the most important food crop in Taiwan, accounting for approximately 5% (166,616 ha) of the total cultivated area. Besides its nutritional value, rice agriculture remains the primary source of livelihood for the majority of rural populations in the country. Rice monitoring is a crucial activity due to official initiatives to ensure the national food security. Because the size of rice fields in Taiwan is relatively small, rice monitoring is traditionally implemented through time-consuming and costly visual interpretation of aerial photos. The Sentinel-1A launched on 3 April 2014 provides the data that have sufficient spatial and temporal resolutions (i.e., 10 m resolution and 12-day revisit cycle) for monitoring small patches of rice fields in the country. This study aimed to develop a phenology-based approach to map rice-growing areas in Taiwan from multi-temporal descending Sentinel-1A VH and VV data. The data were processed for the second rice cropping season (July‒December) in 2015, consisting four main steps: (1) data pre-processing, including radiometric and geometric corrections, and speckle noise filtering of the VH and VV backscattering coefficient data, (2) normalization difference sigma-naught index (NDSI) calculation based on the sowing and heading periods obtained from the analysis of rice crop phenology in the region, (3) threshold-based rice classification using the expectation-maximization method, and (4) accuracy assessment of the mapping results. The mapping results compared with the ground reference data indicated that the overall accuracies and Kappa coefficients achieved for the VH data were 92.0% and 0.84, while the values for the VV data were 81.1% and 0.62, respectively. The mapping results further verified with the government's rice area statistics reaffirmed the consistency between these two datasets with the root mean square error (RMSE) less than 1%, in both cases. This study demonstrates the potential application of multi-temporal

  4. Multi-temporal SAR Interferometry for Monitoring of Man-Made Sfructures.

    OpenAIRE

    Patrício, Glória; Guimarães, Pedro; Sousa, Joaquim S.; Ruiz, António M.; Bastos, Luísa

    2016-01-01

    Multi-temporal InSAR (MTI) methods are effective tools for monitoring and investigating surface displacement on Earth based on conventional radar interferometry. These techniques allow us to measure deformation with uncertainties up to one millimeter per year, interpreting time series of interferometric phases at coherent/stable point scatterers. Considering the regular revisit time and wide-area coverage of satellite radar sensors, and that stable points usually correspond to buildings and o...

  5. [Review of change detection methods using multi-temporal remotely sensed images].

    Science.gov (United States)

    Yin, Shou-Jing; Wu, Chuan-Qing; Wang, Qiao; Ma, Wan-Dong; Zhu, Li; Yao, Yan-Juan; Wang, Xue-Lei; Wu, Di

    2013-12-01

    With the development of platforms and sensors, continuous repetition of remote sensing observation of the earth surface has been realized, and a mass of multi-source, multi-scale, multi-resolution remote sensing data has been accumulated. Those images have detailedly recorded the changing process of ground objects on the earth, which makes the long term global change research, such as change detection, based on remote sensing become possible, and greatly push forward the research on image processing and application. Although plenty of successful research has been reported, there are still enormous challenges in multi-temporal imagery change detection. A relatively complete mature theoretical system has not formed, and there is still a lack of systematic summary of research progress. Firstly, the current progress in change detection methods using multi-temporal remotely sensed imagery has been reviewed in this paper. Then, the methods are classified into three categories and summarized according to the type and amount of the input data, single-phase post-classification comparison, two-phase comparison, and time series analysis. After that, the possible existing problems in the current development of multi-temporal change detection are analyzed, and the development trend is discussed finally.

  6. Analysis of urban development by means of multi-temporal fragmentation metrics from LULC data

    Science.gov (United States)

    Sapena, M.; Ruiz, L. A.

    2015-04-01

    The monitoring and modelling of the evolution of urban areas is increasingly attracting the attention of land managers and administration. New data, tools and methods are being developed and made available for a better understanding of these dynamic areas. We study and analyse the concept of landscape fragmentation by means of GIS and remote sensing techniques, particularly focused on urban areas. Using LULC data obtained from the European Urban Atlas dataset developed by the local component of Copernicus Land Monitoring Services (scale 1:10,000), the urban fragmentation of the province of Rome is studied at 2006 and 2012. A selection of indices that are able to measure the land cover fragmentation level in the landscape are obtained employing a tool called IndiFrag, using as input data LULC data in vector format. In order to monitor the urban morphological changes and growth patterns, a new module with additional multi-temporal metrics has been developed for this purpose. These urban fragmentation and multi-temporal indices have been applied to the municipalities and districts of Rome, analysed and interpreted to characterise quantity, spatial distribution and structure of the urban change. This methodology is applicable to different regions, affording a dynamic quantification of urban spatial patterns and urban sprawl. The results show that urban form monitoring with multi-temporal data using these techniques highlights urbanization trends, having a great potential to quantify and model geographic development of metropolitan areas and to analyse its relationship with socioeconomic factors through the time.

  7. A Hierarchical Multi-Temporal InSAR Method for Increasing the Spatial Density of Deformation Measurements

    Directory of Open Access Journals (Sweden)

    Tao Li

    2014-04-01

    Full Text Available Point-like targets are useful in providing surface deformation with the time series of synthetic aperture radar (SAR images using the multi-temporal interferometric synthetic aperture radar (MTInSAR methodology. However, the spatial density of point-like targets is low, especially in non-urban areas. In this paper, a hierarchical MTInSAR method is proposed to increase the spatial density of deformation measurements by tracking both the point-like targets and the distributed targets with the temporal steadiness of radar backscattering. To efficiently reduce error propagation, the deformation rates on point-like targets with lower amplitude dispersion index values are first estimated using a least squared estimator and a region growing method. Afterwards, the distributed targets are identified using the amplitude dispersion index and a Pearson correlation coefficient through a multi-level processing strategy. Meanwhile, the deformation rates on distributed targets are estimated during the multi-level processing. The proposed MTInSAR method has been tested for subsidence detection over a suburban area located in Tianjin, China using 40 high-resolution TerraSAR-X images acquired between 2009 and 2010, and validated using the ground-based leveling measurements. The experiment results indicate that the spatial density of deformation measurements can be increased by about 250% and that subsidence accuracy can reach to the millimeter level by using the hierarchical MTInSAR method.

  8. Identification of rice field using Multi-Temporal NDVI and PCA method on Landsat 8 (Case Study: Demak, Central Java)

    Science.gov (United States)

    Sukmono, Abdi; Ardiansyah

    2017-01-01

    Paddy is one of the most important agricultural crop in Indonesia. Indonesia’s consumption of rice per capita in 2013 amounted to 78,82 kg/capita/year. In 2017, the Indonesian government has the mission of realizing Indonesia became self-sufficient in food. Therefore, the Indonesian government should be able to seek the stability of the fulfillment of basic needs for food, such as rice field mapping. The accurate mapping for rice field can use a quick and easy method such as Remote Sensing. In this study, multi-temporal Landsat 8 are used for identification of rice field based on Rice Planting Time. It was combined with other method for extract information from the imagery. The methods which was used Normalized Difference Vegetation Index (NDVI), Principal Component Analysis (PCA) and band combination. Image classification is processed by using nine classes, those are water, settlements, mangrove, gardens, fields, rice fields 1st, rice fields 2nd, rice fields 3rd and rice fields 4th. The results showed the rice fields area obtained from the PCA method was 50,009 ha, combination bands was 51,016 ha and NDVI method was 45,893 ha. The accuracy level was obtained PCA method (84.848%), band combination (81.818%), and NDVI method (75.758%).

  9. Landuse change detection in a surface coal mine area using multi-temporal high resolution satellite images

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, N.; Duzgun, S.; Kemal Emil, M. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering

    2010-07-01

    Changes in the landcover and landuse of a mine area can be caused by surface mining activities, exploitation of ore and stripping and dumping overburden. In order to identify the long-term impacts of mining on the environment and land cover, these changes must be continuously monitored. A facility to regularly observe the progress of surface mining and reclamation is important for effective enforcement of mining and environmental regulations. Remote sensing provides a powerful tool to obtain rigorous data and reduce the need for time-consuming and expensive field measurements. The purpose of this study was to conduct post classification change detection for identifying, quantifying, and analyzing the spatial response of landscape due to surface lignite coal mining activities in Goynuk, Bolu, Turkey, from 2004 to 2008. The paper presented the research algorithm which involved acquiring multi temporal high resolution satellite data; preprocessing the data; performing image classification using maximum likelihood classification algorithm and performing accuracy assessment on the classification results; performing post classification change detection algorithm; and analyzing the results. Specifically, the paper discussed the study area, data and methodology, and image preprocessing using radiometric correction. Image classification and change detection were also discussed. It was concluded that the mine and dump area decreased by 192.5 ha from 2004 to 2008 and was caused by the diminishing reserves in the area and decline in the required production. 5 refs., 2 tabs., 4 figs.

  10. Multi-temporal SAR data analysis for landcover, water-level changes, and subsidence studies in Southeastern Louisiana

    Science.gov (United States)

    Kwoun, O.; Lu, Z.

    2006-12-01

    We used multi-temporal European Remote Sensing Satellites 1 and 2 (ERS-1/2), Environment Satellite (ENVISAT), and Canadian RADARSAT-1 Synthetic Aperture Radar (SAR) images for ecological, hydrological, and geological studies of the Southeastern Louisiana coastal flood zone. First, we present a distinctive correlation among the seasonal changes in SAR backscatter, interferometric coherence, and land cover types with the associated normalized difference vegetation indices. Second, we demonstrate the use of C-band SAR images to measure changes in the water-level beneath moderately dense swamp forests, at a vertical accuracy and spatial resolution that is not possible with the current gauge-based measurements. Finally, we apply the conventional SAR interferometry (InSAR) and the Permanent Scatterer InSAR techniques to map land surface subsidence in New Orleans and the surrounding area; the comparison of measured subsidence patterns shows certain discrepancies that are probably due to atmospheric delays in this humid area. Our study demonstrates the importance of SAR data for understanding this coastal flood zone and the associated ecological, hydrological, and geological processes.

  11. Multi-temporal UAV based data for mapping crop type and structure in smallholder dominated Tanzanian agricultural landscape

    Science.gov (United States)

    Nagol, J. R.; Chung, C.; Dempewolf, J.; Maurice, S.; Mbungu, W.; Tumbo, S.

    2015-12-01

    Timely mapping and monitoring of crops like Maize, an important food security crop in Tanzania, can facilitate timely response by government and non-government organizations to food shortage or surplus conditions. Small UAVs can play an important role in linking the spaceborne remote sensing data and ground based measurement to improve the calibration and validation of satellite based estimates of in-season crop metrics. In Tanzania most of the growing season is often obscured by clouds. UAV data, if collected within a stratified statistical sampling framework, can also be used to directly in lieu of spaceborne data to infer mid-season yield estimates at regional scales.Here we present an object based approach to estimate crop metrics like crop type, area, and height using multi-temporal UAV based imagery. The methods were tested at three 1km2 plots in Kilosa, Njombe, and Same districts in Tanzania. At these sites both ground based and UAV based data were collected on a monthly time-step during the year 2015 growing season. SenseFly eBee drone with RGB and NIR-R-G camera was used to collect data. Crop type classification accuracies of above 85% were easily achieved.

  12. Multi-Temporal Monitoring of Slow Moving Landslides in South Pindus Mountain Range, Greece

    Science.gov (United States)

    Psychogyiou, Christina; Papoutsis, Ioannis; Kontoes, Charalambos; Poyiadji, Eleftheria; Spanou, Natalia; Klimis, Nikolaos

    2015-05-01

    The high frequency of landslide occurrences in Central and Western Greece, part of the Pindus mountain range, is now approached by exploiting the high temporal sampling rate of historical ERS-1/2 and ENVISAT SAR imagery in combination with the Multi Temporal Interferometry (MTI) technique. An existing well-established ground truth dataset is updated and enriched with the diachronic MTI results. Critical areas prone to slide are evaluated through susceptibility assessment and mapping taking into consideration the challenging environmental factors which dominate at the area of interest. A set of supplementary interesting geophysical and structural MTI detections at the region of analysis are additionally discussed.

  13. Multi-Temporal InSAR Analysis of Wenjiagou Landslide using Distributed Scatterers

    Science.gov (United States)

    Wang, Chao; Zhang, Zhengjia; Zhang, Hong; Tang, Yixian

    2015-05-01

    This paper presents a multi-temporal InSAR method to monitor landslide movement at wenjiagou using Distributed Scatterers (DS). In this study, TDX and TSX bistatic SAR data are processed to obtain high precision DEM of the pose-landslide. DSs are efficiently identified using classified information and statistical characteristics. A series of Radarsat-2 HH polarization images collected in Wenjiagou from 2014.6 to 2014.9 are used to generate the deformation of the giant landslide. The experimental results show that there are obvious ground movement detected in the depositing area of the landslide during the observation.

  14. Exploring Google Earth Engine platform for big data processing: classification of multi-temporal satellite imagery for crop mapping

    Science.gov (United States)

    Shelestov, Andrii; Lavreniuk, Mykola; Kussul, Nataliia; Novikov, Alexei; Skakun, Sergii

    2017-02-01

    Many applied problems arising in agricultural monitoring and food security require reliable crop maps at national or global scale. Large scale crop mapping requires processing and management of large amount of heterogeneous satellite imagery acquired by various sensors that consequently leads to a “Big Data” problem. The main objective of this study is to explore efficiency of using the Google Earth Engine (GEE) platform when classifying multi-temporal satellite imagery with potential to apply the platform for a larger scale (e.g. country level) and multiple sensors (e.g. Landsat-8 and Sentinel-2). In particular, multiple state-of-the-art classifiers available in the GEE platform are compared to produce a high resolution (30 m) crop classification map for a large territory ( 28,100 km2 and 1.0 M ha of cropland). Though this study does not involve large volumes of data, it does address efficiency of the GEE platform to effectively execute complex workflows of satellite data processing required with large scale applications such as crop mapping. The study discusses strengths and weaknesses of classifiers, assesses accuracies that can be achieved with different classifiers for the Ukrainian landscape, and compares them to the benchmark classifier using a neural network approach that was developed in our previous studies. The study is carried out for the Joint Experiment of Crop Assessment and Monitoring (JECAM) test site in Ukraine covering the Kyiv region (North of Ukraine) in 2013. We found that Google Earth Engine (GEE) provides very good performance in terms of enabling access to the remote sensing products through the cloud platform and providing pre-processing; however, in terms of classification accuracy, the neural network based approach outperformed support vector machine (SVM), decision tree and random forest classifiers available in GEE.

  15. Deforestation monitoring in the Amazon River estuary by multi-temporal Envisat ScanSAR data

    Science.gov (United States)

    Chen, F.; Ishwaran, N.; Brito Pezzuti, J. C.

    2016-04-01

    In this study, we have capitalized on the all-weather, all-day operational capability of spaceborne synthetic aperture radar (SAR) systems and used multi-temporal (from 2002 to 2006), multi-track (track 174, 360 and 447) Envisat ScanSAR amplitude images for deforestation mapping and change detection in the Amazon River estuary. A synergistic approach to deforestation mapping was adopted using SAR backscattering anomalies, the neighbouring forest constraint and DEM-derived slopes based on the three following characteristics: (1) backscattering is reduced in regions suspected to have undergone deforestation; (2) open regions without neighbouring forests were identified for removal; and (3) false-alarms linked to water bodies are mitigated using the shape threshold of flat-slope objects. Our results show that deforestation in the Amazon River estuary continues to be a serious problem, particularly along the rivers, streams or roads, which are more susceptible to anthropogenic activities than other areas. Up to 2006, the deforested portion accounts for 4.6 per cent (3,096,000 pixels) of the entire study site of approximately 458,000 square kilometers (67,320,000 pixels). However, this figure, validated by Landsat ETM images, may have overestimated deforestation to some extent. Nevertheless, multi-temporal analysis using SAR systems, as done in this study, have a clear potential for surveillance of deforestation in the Amazon, particularly in light of the frequent cloud cover typical of the area and the limitations of deforestation monitoring by means of optical satellite imagery.

  16. Multi-temporal MRI carpal bone volumes analysis by principal axes registration

    Science.gov (United States)

    Ferretti, Roberta; Dellepiane, Silvana

    2016-03-01

    In this paper, a principal axes registration technique is presented, with the relevant application to segmented volumes. The purpose of the proposed registration is to compare multi-temporal volumes of carpal bones from Magnetic Resonance Imaging (MRI) acquisitions. Starting from the study of the second-order moment matrix, the eigenvectors are calculated to allow the rotation of volumes with respect to reference axes. Then the volumes are spatially translated to become perfectly overlapped. A quantitative evaluation of the results obtained is carried out by computing classical indices from the confusion matrix, which depict similarity measures between the volumes of the same organ as extracted from MRI acquisitions executed at different moments. Within the medical field, the way a registration can be used to compare multi-temporal images is of great interest, since it provides the physician with a tool which allows a visual monitoring of a disease evolution. The segmentation method used herein is based on the graph theory and is a robust, unsupervised and parameters independent method. Patients affected by rheumatic diseases have been considered.

  17. Determination of the Impact of Urbanization on Agricultural Lands using Multi-temporal Satellite Sensor Images

    Science.gov (United States)

    Kaya, S.; Alganci, U.; Sertel, E.; Ustundag, B.

    2015-12-01

    Throughout the history, agricultural activities have been performed close to urban areas. Main reason behind this phenomenon is the need of fast marketing of the agricultural production to urban residents and financial provision. Thus, using the areas nearby cities for agricultural activities brings out advantage of easy transportation of productions and fast marketing. For decades, heavy migration to cities has directly and negatively affected natural grasslands, forests and agricultural lands. This pressure has caused agricultural lands to be changed into urban areas. Dense urbanization causes increase in impervious surfaces, heat islands and many other problems in addition to destruction of agricultural lands. Considering the negative impacts of urbanization on agricultural lands and natural resources, a periodic monitoring of these changes becomes indisputably important. At this point, satellite images are known to be good data sources for land cover / use change monitoring with their fast data acquisition, large area coverages and temporal resolution properties. Classification of the satellite images provides thematic the land cover / use maps of the earth surface and changes can be determined with GIS based analysis multi-temporal maps. In this study, effects of heavy urbanization over agricultural lands in Istanbul, metropolitan city of Turkey, were investigated with use of multi-temporal Landsat TM satellite images acquired between 1984 and 2011. Images were geometrically registered to each other and classified using supervised maximum likelihood classification algorithm. Resulting thematic maps were exported to GIS environment and destructed agricultural lands by urbanization were determined using spatial analysis.

  18. Object-based illumination normalization for multi-temporal satellite images in urban area

    Science.gov (United States)

    Su, Nan; Zhang, Ye; Tian, Shu; Yan, Yiming

    2016-09-01

    Multi-temporal satellite images acquisition with different illumination conditions cause radiometric difference to have a huge effect on image quality during remote sensing image processing. In particular, image matching of satellite stereo images with great difference between acquisition dates is very difficult for the high-precision DSM generation in the field of satellite photogrammetry. Therefore, illumination normalization is one of the greatest application technology to eliminate radiometric difference for image matching and other image applications. In this paper, we proposed a novel method of object-based illumination normalization to improve image matching of different temporal satellite stereo images in urban area. Our proposed method include two main steps: 1) the object extraction 2) multi-level illumination normalization. Firstly, we proposed a object extraction method for the same objects extraction among the multi-temporal satellite images, which can keep the object structural attribute. Moreover, the multi-level illumination normalization is proposed by combining gradient domain method and singular value decomposition (SVD) according to characteristic information of relevant objects. Our proposed method has great improvement for the illumination of object area to be benefit for image matching in urban area with multiple objects. And the histogram similarity parameter and matching rate are used for illumination consistency quantitative evaluation. The experiments have been conducted on different satellite images with different acquisition dates in the same urban area to verify the effectiveness of our proposed method. The experimental results demonstrate a good performance by comparing other methods.

  19. Monitoring Landslides in Western Mountainous Areas of China Using Advanced Multi-Temporal InSAR Techniques

    Science.gov (United States)

    Dong, Jie; Liao, Mingsheng; Zhang, Lu; Gong, Jianya

    2016-08-01

    Disasters, caused by landslide, rock fall, debris flow, ground fissure, etc., are one of the significant natural catastrophes, threatening and influencing the socio-economic conditions around the world. China is one of the countries that suffer heavily from such geo-hazards. And most landslides take place in the mountainous valley areas of western China. With its wide coverage and sub-centimeter accuracy, radar remote sensing has already proven its potential for remotely measuring unstable slopes. Differential InSAR (D-InSAR) is used to recognize known landslides and find potential unstable slopes in a region scale. Then, for a specific landslide, advanced multi-temporal InSAR method is exploited to characterize its surface deformation by obtaining time-series displacement on coherent targets. Among them, the PSI technique exploits only PSs exhibiting high phase stability in a stack of interferograms, which generally exist in urban areas. But, in the case of rural environment characterized by vegetated or low reflectivity homogeneous regions, few PSs could be identified. As a complement of persistent scatterers, distributed scatterers widely existing in rural areas can be exploited. DSs decorrelate slowly and can be found from homogeneous ground, scattered outcrops, debris flows, non-cultivated lands and desert areas. In this poster, a distributed scatterers-based InSAR technique, making use of PSs and DSs, is proposed. At first, we will use D-InSAR technique to detect landslides. Then, both PSI and DS-InSAR will be implemented to monitor interested landslides. And a comparison study of these two methods are conducted.

  20. Analysis of elevation changes detected from multi-temporal LiDAR surveys in forested landslide terrain in western Oregon

    Science.gov (United States)

    Burns, W.J.; Coe, J.A.; Kaya, B.S.; Ma, L.

    2010-01-01

    We examined elevation changes detected from two successive sets of Light Detection and Ranging (LiDAR) data in the northern Coast Range of Oregon. The first set of LiDAR data was acquired during leafon conditions and the second set during leaf-off conditions. We were able to successfully identify and map active landslides using a differential digital elevation model (DEM) created from the two LiDAR data sets, but this required the use of thresholds (0.50 and 0.75 m) to remove noise from the differential elevation data, visual pattern recognition of landslideinduced elevation changes, and supplemental QuickBird satellite imagery. After mapping, we field-verified 88 percent of the landslides that we had mapped with high confidence, but we could not detect active landslides with elevation changes of less than 0.50 m. Volumetric calculations showed that a total of about 18,100 m3 of material was missing from landslide areas, probably as a result of systematic negative elevation errors in the differential DEM and as a result of removal of material by erosion and transport. We also examined the accuracies of 285 leaf-off LiDAR elevations at four landslide sites using Global Positioning System and total station surveys. A comparison of LiDAR and survey data indicated an overall root mean square error of 0.50 m, a maximum error of 2.21 m, and a systematic error of 0.09 m. LiDAR ground-point densities were lowest in areas with young conifer forests and deciduous vegetation, which resulted in extensive interpolations of elevations in the leaf-on, bare-earth DEM. For optimal use of multi-temporal LiDAR data in forested areas, we recommend that all data sets be flown during leaf-off seasons.

  1. Assessing the uncertainty of biomass change estimates obtained using multi-temporal field, lidar sampling, and satellite imagery on the Kenai Peninsula of Alaska (Invited)

    Science.gov (United States)

    Andersen, H.

    2013-12-01

    changes estimated using 1) multi-temporal lidar data, 2) multi-temporal lidar and Landsat TM data, and 3) multi-temporal Landsat TM data. Both analytical and resampling (i.e. bootstrapping) approaches to variance estimation were presented and evaluated.

  2. Beach monitoring using Unmanned Aerial Vehicles: results of a multi-temporal study

    Science.gov (United States)

    Casella, Elisa; Rovere, Alessio; Casella, Marco; Pedroncini, Andrea; Ferrari, Marco; Vacchi, Matteo; Firpo, Marco

    2015-04-01

    The application of Unmanned Aerial Vehicles and photogrammetry techniques in earth sciences is flourishing. In this study, we show how we applied small Unmanned Aerial Vehicles to the study of topographic changes of a beach in Italy, NW Mediterranean Sea. We surveyed the same stretch of coastline three times in 5 months, obtaining ortophotos and digital elevation models of the beach using a structure from motion approach. We then calculated the difference in beach topography between each time step, and we related topography changes to both human and natural modifications of the beach morphology that can be inferred from aerial photos or wave data. We conclude that small drones have the potential to open new possibilities for beach monitoring studies, and can be successfully employed for multi-temporal monitoring studies at relatively low cost.

  3. Monitoring Structural Health of Different Types of Bridges Using Advanced Multi-Temporal InSAR

    Science.gov (United States)

    Qin, Xiaoqiong; Liao, Mingsheng; Yang, Mengshi; Zhang, Lu; Balz, Timo

    2016-08-01

    Since the bridges paly a significance role in national economic development and transportation safety, the structure health and safety of bridges aroused a lot of concern in society and become a hotspot research in earth observation and civil engineering. However, the materials degradation and environmental stresses increase may destroy the structure of bridges and pose significant risks to public safety and quality of life. This highlighted the importance of developing effective structure health monitoring strategies to reflect the current status of bridges and identify structural problems. In this work, an advanced multi-temporal InSAR technique is introduced into deformation monitoring of bridges. We focus on analysis the distribution of PSs, distinction of stable and unstable parts and recognition temporal-spatial deformation characteristics at the scale of single bridge through the examples of different types of bridges in Tianjin and Shanghai.

  4. Monitoring of rock glacier dynamics by multi-temporal UAV images

    Science.gov (United States)

    Morra di Cella, Umberto; Pogliotti, Paolo; Diotri, Fabrizio; Cremonese, Edoardo; Filippa, Gianluca; Galvagno, Marta

    2015-04-01

    During the last years several steps forward have been made in the comprehension of rock glaciers dynamics mainly for their potential evolution into rapid mass movements phenomena. Monitoring the surface movement of creeping mountain permafrost is important for understanding the potential effect of ongoing climate change on such a landforms. This study presents the reconstruction of two years of surface movements and DEM changes obtained by multi-temporal analysis of UAV images (provided by SenseFly Swinglet CAM drone). The movement rate obtained by photogrammetry are compared to those obtained by differential GNSS repeated campaigns on almost fifty points distributed on the rock glacier. Results reveals a very good agreements between both rates velocities obtained by the two methods and vertical displacements on fixed points. Strengths, weaknesses and shrewdness of this methods will be discussed. Such a method is very promising mainly for remote regions with difficult access.

  5. Changes in Amazon Forest Structure and Canopy Illumination from Multi-temporal Lidar Data

    Science.gov (United States)

    Leitold, V.; Morton, D. C.; Keller, M. M.; Cook, B.

    2015-12-01

    Lidar remote sensing of tropical forests provides unprecedented detail on 3D vegetation structure to support in-depth studies of ecosystem processes and carbon dynamics across large landscapes. Here, we used high-resolution, multi-temporal airborne lidar data from nine terra firme forest sites (total area = 3500 ha) in the Brazilian Amazon to estimate spatial and temporal patterns of forest disturbance and associated changes in canopy illumination. Across sites, we observed large variability in mean canopy height (15.7 m to 28.1 m) and the vertical distributions of forest vegetation and light penetration. At the site scale, lidar-derived canopy height models from repeat surveys showed minimal change in canopy structure over time intervals of 1 to 4 years, with nearly identical initial and final canopy height distributions. Annualized rates of total canopy turnover, based on losses in canopy height between lidar collections, ranged from 0.66 to 2.57% yr-1, with a mean value of 1.59% yr-1 across sites. Field estimates of tree crown sizes were used to classify canopy turnover into branch fall, tree fall and multiple tree fall events. Partial crown losses occurred most frequently across the landscape (40% of all events), but accounted for only a small fraction of the total turnover area (10%). Size-frequency distributions of canopy turnover followed a power-law distribution with a decline in the number of events with increasing size across all sites (range of λ between 1.26 - 1.35). The distributions of illumination conditions before and after disturbance events were inverted, as fully-illuminated crowns were replaced by low-light conditions within patches of canopy loss. Estimates of the spatial and temporal patterns of Amazon forest disturbance and recovery from multi-temporal lidar data complement information from plot-scale (≤ 1ha) studies to provide a more complete understanding of regional variability in ecosystem structure and function under current climate.

  6. Monitoring of environmental change in Dzungar basin by the analysis of multi temporal satellite data sets

    Science.gov (United States)

    Nakayama, Y.; Yanagi, T.; Nishimura, J.

    In recent 40-50 years, rapid environmental changes are shown in the arid and semi-arid regions of the inland areas in each continent. The environment change situation is especially remarkable at closed lakes and their vicinity of the Asian continent inland. This study aimed to investigate the environmental change and its cause in Dzungar basin of the central Asia through the analysis of multi-temporal satellite data sets. The multi temporal and multi stage satellite data sets were firstly created by using high spatial resolution satellite data such as LANDSAT/MSS TM, Terra/ASTER, and JERS-1/OPS, and wide observation satellite data such as NOAA/AVHRR and Terra/MODIS. Next, the fluctuations of the past about 50 years in water area of lakes were investigated in detail by analyzing the data sets, and also changes in the irrigated agricultural lands along the inflow rivers, and the snow and glacier covering the mountainous district were investigated. Finally, hydrological change situation and its cause in the object area were examined by comparing the analyzed results with meteorological data and auxiliary sources. The results of this study are summarized as follows; Most of closed lakes in Dzungar basin have shown the rapid shrinkages in the past about 50 years. However, it changed into the remarkable expansion of the water area since 2001. According to the analysis results of changes in the irrigated agricultural lands, snow and glacier extents, it was shown that the influence of human activities such as development of irrigation lands was bigger than the influence of the nature fluctuation based on the global warming as a cause of the change in closed lakes.

  7. Integrated snow and avalanche monitoring syatem for Indian Himalaya using multi-temporal satellite imagery and ancillary data

    Science.gov (United States)

    Sharma, S. S.; Mani, Sneh; Mathur, P.

    . Different methods have been used for the analysis of the temporal changes in satellite images. Multi-sensor data fusion techniques have been applied to increase the accuracy of classification, and also for extraction of necessary information about characteristics of snow and avalanches and the ground conditions. The results of the analysis of time series of last two winters are reported. The study confirms that significant changes in snow characteristics and wetness are mainly due to large variations in temperature at these altitudes, which contribute towards avalanche activities in early winter. A definite relationship has been observed between snow wetness, altitude and period of the year with respect to the probability of an avalanche occurrence. Snow wetness is found to be inversely proportional to the altitude, whereas probability of an avalanche is directly proportional to the wetness of snow, lying either over thin grass or boulder-covered ground. The results were verified through extensive field measurements. The emphasis has been laid on establishment of a dense network of Automatic Weather Stations (AWS), Upper Air Stations (UAS) and observatories in entire Himalaya; development of GIS based data bases using satellite imageries and other ancillary data for weather, snow and land cover monitoring. Records of past years will provide base information for realistic estimation of the impact of climatic changes and confidence to predict the weather and avalanches in various regions of Himalaya. Key Words: Integrated Monitoring System, Time series multi-sensor/multi-temporal Satellite Imageries, Multi-sensor Data Fusion, Change Detection, Snow characteristics

  8. Integrated snow and avalanche monitoring system for Indian Himalaya using multi-temporal satellite imagery and ancillary data

    Science.gov (United States)

    Sharma, S. S.; Mani, Sneh; Mathur, P.

    . Different methods have been used for the analysis of the temporal changes in satellite images. Multi-sensor data fusion techniques have been applied to increase the accuracy of classification, and also for extraction of necessary information about characteristics of snow and avalanches and the ground conditions. The results of the analysis of time series of last two winters are reported. The study confirms that significant changes in snow characteristics and wetness are mainly due to large variations in temperature at these altitudes, which contribute towards avalanche activities in early winter. A definite relationship has been observed between snow wetness, altitude and period of the year with respect to the probability of an avalanche occurrence. Snow wetness is found to be inversely proportional to the altitude, whereas probability of an avalanche is directly proportional to the wetness of snow, lying either over thin grass or boulder-covered ground. The results were verified through extensive field measurements. The emphasis has been laid on establishment of a dense network of Automatic Weather Stations (AWS), Upper Air Stations (UAS) and observatories in entire Himalaya; development of GIS based data bases using satellite imageries and other ancillary data for weather, snow and land cover monitoring. Records of past years will provide base information for realistic estimation of the impact of climatic changes and confidence to predict the weather and avalanches in various regions of Himalaya. Key Words: Integrated Monitoring System, Time series multi-sensor/multi-temporal Satellite Imageries, Multi-sensor Data Fusion, Change Detection, Snow characteristics

  9. Decadal region-wide and glacier-wide mass balances derived from multi-temporal ASTER satellite digital elevation models. Validation over the Mont-Blanc area

    Science.gov (United States)

    Berthier, Etienne; Cabot, Vincent; Vincent, Christian; Six, Delphine

    2016-06-01

    Since 2000, a vast archive of stereo-images has been built by the Advanced Spaceborne Thermal Emission and Reflection (ASTER) satellite. Several studies already extracted glacier mass balances from multi-temporal ASTER digital elevation models (DEMs) but they lacked accurate independent data for validation. Here, we apply a linear regression to a time series of 3D-coregistered ASTER DEMs to estimate the rate of surface elevation changes (dh/dtASTER) and geodetic mass balances of Mont-Blanc glaciers (155 km²) between 2000 and 2014. Validation using field and spaceborne geodetic measurements reveals large errors at the individual pixel level (> 1 m a-1) and an accuracy of 0.2-0.3 m a-1 for dh/dtASTER averaged over areas larger than 1 km². For all Mont-Blanc glaciers, the ASTER region-wide mass balance (-1.05±0.37 m water equivalent (w.e.) a-1) agrees remarkably with the one measured using Spot5 and Pléiades DEMs (-1.06±0.23 m w.e. a-1) over their common 2003-2012 period. This multi-temporal ASTER DEM strategy leads to smaller errors than the simple differencing of two ASTER DEMs. By extrapolating dh/dtASTER to mid-February 2000, we infer a mean penetration depth of about 9±3 m for the C-band Shuttle Radar Topographic Mission (SRTM) radar signal, with a strong altitudinal dependency (range 0-12 m). This methodology thus reveals the regional pattern of glacier surface elevation changes and improves our knowledge of the penetration of the radar signal into snow and ice.

  10. Decadal region-wide and glacier-wide mass balances derived from multi-temporal ASTER satellite digital elevation models. Validation over the Mont-Blanc area

    Directory of Open Access Journals (Sweden)

    Etienne eBerthier

    2016-06-01

    Full Text Available Since 2000, a vast archive of stereo-images has been built by the Advanced Spaceborne Thermal Emission and Reflection (ASTER satellite. Several studies already extracted glacier mass balances from multi-temporal ASTER digital elevation models (DEMs but they lacked accurate independent data for validation. Here, we apply a linear regression to a time series of 3D-coregistered ASTER DEMs to estimate the rate of surface elevation changes (dh/dtASTER and geodetic mass balances of Mont-Blanc glaciers (155 km² between 2000 and 2014. Validation using field and spaceborne geodetic measurements reveals large errors at the individual pixel level (> 1 m a-1 and an accuracy of 0.2-0.3 m a-1 for dh/dtASTER averaged over areas larger than 1 km². For all Mont-Blanc glaciers, the ASTER region-wide mass balance (-1.05±0.37 m water equivalent (w.e. a-1 agrees remarkably with the one measured using Spot5 and Pléiades DEMs (-1.06±0.23 m w.e. a-1 over their common 2003-2012 period. This multi-temporal ASTER DEM strategy leads to smaller errors than the simple differencing of two ASTER DEMs. By extrapolating dh/dtASTER to mid-February 2000, we infer a mean penetration depth of about 9±3 m for the C-band Shuttle Radar Topographic Mission (SRTM radar signal, with a strong altitudinal dependency (range 0-12 m. This methodology thus reveals the regional pattern of glacier surface elevation changes and improves our knowledge of the penetration of the radar signal into snow and ice.

  11. Usefulness and accuracy of MALDI-TOF mass spectrometry as a supplementary tool to identify mosquito vector species and to invest in development of international database.

    Science.gov (United States)

    Raharimalala, F N; Andrianinarivomanana, T M; Rakotondrasoa, A; Collard, J M; Boyer, S

    2017-09-01

    Arthropod-borne diseases are important causes of morbidity and mortality. The identification of vector species relies mainly on morphological features and/or molecular biology tools. The first method requires specific technical skills and may result in misidentifications, and the second method is time-consuming and expensive. The aim of the present study is to assess the usefulness and accuracy of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a supplementary tool with which to identify mosquito vector species and to invest in the creation of an international database. A total of 89 specimens belonging to 10 mosquito species were selected for the extraction of proteins from legs and for the establishment of a reference database. A blind test with 123 mosquitoes was performed to validate the MS method. Results showed that: (a) the spectra obtained in the study with a given species differed from the spectra of the same species collected in another country, which highlights the need for an international database; (b) MALDI-TOF MS is an accurate method for the rapid identification of mosquito species that are referenced in a database; (c) MALDI-TOF MS allows the separation of groups or complex species, and (d) laboratory specimens undergo a loss of proteins compared with those isolated in the field. In conclusion, MALDI-TOF MS is a useful supplementary tool for mosquito identification and can help inform vector control. © 2017 The Royal Entomological Society.

  12. Discrimination rice cropping systems using multi-temporal Proba-V data in the Mekong Delta, Vietnam

    Science.gov (United States)

    Son, Nguyen-Thanh; Chen, Chi-Farn; Chen, Cheng-Ru; Chang, Ly-Yu; Chiang, Shou-Hao; Lau, Khin-Va

    2016-04-01

    Rice is considered a main source of livelihoods for several billions of people worldwide and plays an important role in the economy of many Asian countries. More than just a food source, rice production is regarded as one of the most important components to maintaining political stability and is also a national subject of economic policy due to domestic food consumption and grain exports. Vietnam is globally one of the largest rice producers and suppliers with more than 80% of the exported rice amount produced from the Mekong River Delta. This delta is one of the three deltas in the world most vulnerable to the climate change, causing the potential loss of rice yields. Thus, spatiotemporal information of rice cropping systems is important for agricultural management to ensure food security and rice grain exports. Coarse resolution satellite data such as MODIS demonstrates the applicability for rice mapping at a large scale. However, the use of MODIS data for such a monitoring purpose still reveals a challenging task due to mixed-pixel issues. The Proba-V satellite launched on 7 May 2013 is a potential candidate for this monitoring purpose because the data include four spectral bands (blue, red, near-infrared and mid-infrared) with a swath of 2,285 km with a spatial resolution of 100 m and temporal resolution of 5 days. This study aimed to investigate the applicability of multi-temporal Proba-V data for mapping rice cropping systems in Mekong Delta River, South Vietnam. The data were processed for 2014-2015 rice cropping seasons, following three main steps: (1) construction of smooth time-series NDVI data, (2) classification of rice cropping systems using crop phenological metrics, and (3) accuracy assessment of the mapping results. The results indicated that the smooth time-series NDVI profiles characterized the temporal spectral responses of rice fields through different growing stages of rice plant, which was critically important for understanding rice crop

  13. Quest for a universal density functional: the accuracy of density functionals across a broad spectrum of databases in chemistry and physics.

    Science.gov (United States)

    Peverati, Roberto; Truhlar, Donald G

    2014-03-13

    Kohn-Sham density functional theory is in principle an exact formulation of quantum mechanical electronic structure theory, but in practice we have to rely on approximate exchange-correlation (xc) functionals. The objective of our work has been to design an xc functional with broad accuracy across as wide an expanse of chemistry and physics as possible, leading--as a long-range goal--to a functional with good accuracy for all problems, i.e. a universal functional. To guide our path towards that goal and to measure our progress, we have developed-building on earlier work of our group-a set of databases of reference data for a variety of energetic and structural properties in chemistry and physics. These databases include energies of molecular processes, such as atomization, complexation, proton addition and ionization; they also include molecular geometries and solid-state lattice constants, chemical reaction barrier heights, and cohesive energies and band gaps of solids. For this paper, we gather many of these databases into four comprehensive databases, two with 384 energetic data for chemistry and solid-state physics and another two with 68 structural data for chemistry and solid-state physics, and we test two wave function methods and 77 density functionals (12 Minnesota meta functionals and 65 others) in a consistent way across this same broad set of data. We especially highlight the Minnesota density functionals, but the results have broader implications in that one may see the successes and failures of many kinds of density functionals when they are all applied to the same data. Therefore, the results provide a status report on the quest for a universal functional.

  14. Multi-temporal sub-pixel landsat ETM+ classification of isolated wetlands in Cuyahoga County, Ohio, USA

    Science.gov (United States)

    The goal of this project was to determine the utility of subpixel processing of multi-temporal Landsat Enhanced Thematic Mapper Plus (ETM+) data for the detection of isolated wetlands greater than 0.50 acres in Cuyahoga County, located in the Erie Drift Plains ecoregion of northe...

  15. Multi-Temporal Land-Cover Classification of Agricultural Areas in Two European Regions with High Resolution Spotlight TerraSAR-X Data

    Directory of Open Access Journals (Sweden)

    Sylvia Herrmann

    2011-04-01

    Full Text Available Functioning ecosystems offer multiple services for human well-being (e.g., food, freshwater, fiber. Agriculture provides several of these services but also can cause negative impacts. Thus, it is essential to derive up-to-date information about agricultural land use and its change. This paper describes the multi-temporal classification of agricultural land use based on high resolution spotlight TerraSAR-X images. A stack of l4 dual-polarized radar images taken during the vegetation season have been used for two different study areas (North of Germany and Southeast Poland. They represent extremely diverse regions with regard to their population density, agricultural management, as well as geological and geomorphological conditions. Thereby, the transferability of the classification method for different regions is tested. The Maximum Likelihood classification is based on a high amount of ground truth samples. Classification accuracies differ in both regions. Overall accuracy for all classes for the German area is 61.78% and 39.25% for the Polish region. Accuracies improved notably for both regions (about 90% when single vegetation classes were merged into groups of classes. Such regular land use classifications, applicable for different European agricultural sites, can serve as basis for monitoring systems for agricultural land use and its related ecosystems.

  16. The quest for a universal density functional: The accuracy of density functionals across a broad spectrum of databases in chemistry and physics

    CERN Document Server

    Peverati, Roberto

    2012-01-01

    Kohn-Sham density functional theory is in principle an exact formulation of quantum mechanical electronic structure theory, but in practice we have to rely on approximate exchange-correlation (xc) functionals. The objective of our work has been to design an xc functional with broad accuracy across as wide an expanse of chemistry and physics as possible, leading-as a long-range goal-to a functional with good accuracy for all problems, i.e., a universal functional. To guide our path toward that goal and to measure our progress, we have developed-building on earlier work in our group-a set of databases of reference data for a variety of energetic and structural properties in chemistry and physics. These databases include energies of molecular processes such as atomization, complexation, proton addition, and ionization; they also include molecular geometries and solid-state lattice constants, chemical reaction barrier heights, and cohesive energies and band gaps of solids. For the present paper we gather many of ...

  17. Challenges of flood monitoring in the Senegal river valley using multi-temporal data

    Science.gov (United States)

    Bruckmann, Laurent; Delbart, Nicolas

    2017-04-01

    In Sub-Saharan Africa, floodplains wetlands play an important role for livelihoods and economy, especially for agriculture and fishing. However, tropical rivers flows are increasingly modified by climate change and dam regulation. In the Senegal river valley, the annual flood, from August to November, is an important water resources creating ecosystems services for people. Senegal river basin face to hydrological changes, due to rainfall diminution during the 1970's and building of large dams during 1980's to secure water resources. Water management and development of irrigation have modified the floodplain functioning. Flood recession agriculture, grazing and fishing are now confronted to a high uncertainty about floods level, duration and extension. Thus, spatiotemporal information of flood extension and duration are important for local communities and stakeholders to ensure food security and ecosystems services. Multi-temporal satellite data demonstrates an important applicability for flood mapping. Aims of this work is to present potentiality of using multi-temporal data from MODIS and new satellite Sentinel-2 for flood monitoring in a Sahelian context. It will also discuss the potential of flood mapping for the analysis of the dynamics of riparian vegetation and flood recession agriculture. This study uses two datasets to explore flood monitoring in Senegal river valley. Firstly, MODIS 8-days data (MOD09A) are first used, because of its temporal resolution of 8 days covering the period from 2000 to 2016. However, MODIS data are limited due to a low spatial resolution, that's why we also use Sentinel-2 data, available since summer 2015. The data were processed by constructing NDWI time-series (NDWI threshold is empirically defined) and extracting NDWI values for each inundated pixel during flood. First results demonstrate that using MODIS on a large scale is enough for analyze interannual variability of the flooded surfaces. We present here maps of flood

  18. Determination of Destructed and Infracted Forest Areas with Multi-temporal High Resolution Satellite Images

    Science.gov (United States)

    Seker, D. Z.; Unal, A.; Kaya, S.; Alganci, U.

    2015-12-01

    Migration from rural areas to city centers and their surroundings is an important problem of not only our country but also the countries that under development stage. This uncontrolled and huge amount of migration brings out urbanization and socio - economic problems. The demand on settling the industrial areas and commercial activities nearby the city centers results with a negative change in natural land cover on cities. Negative impacts of human induced activities on natural resources and land cover has been continuously increasing for decades. The main human activities that resulted with destruction and infraction of forest areas can be defined as mining activities, agricultural activities, industrial / commercial activities and urbanization. Temporal monitoring of the changes in spatial distribution of forest areas is significantly important for effective management and planning progress. Changes can occur as spatially large destructions or small infractions. Therefore there is a need for reliable, fast and accurate data sources. At this point, satellite images proved to be a good data source for determination of the land use /cover changes with their capability of monitoring large areas with reasonable temporal resolutions. Spectral information derived from images provides discrimination of land use/cover types from each other. Developments in remote sensing technology in the last decade improved the spatial resolution of satellites and high resolution images were started to be used to detect even small changes in the land surface. As being the megacity of Turkey, Istanbul has been facing a huge migration for the last 20 years and effects of urbanization and other human based activities over forest areas are significant. Main focus of this study is to determine the destructions and infractions in forest areas of Istanbul, Turkey with 2.5m resolution SPOT 5 multi-temporal satellite imagery. Analysis was mainly constructed on threshold based classification of

  19. Relative accuracy and availability of an Irish National Database of dispensed medication as a source of medication history information: observational study and retrospective record analysis.

    LENUS (Irish Health Repository)

    Grimes, T

    2013-01-27

    WHAT IS KNOWN AND OBJECTIVE: The medication reconciliation process begins by identifying which medicines a patient used before presentation to hospital. This is time-consuming, labour intensive and may involve interruption of clinicians. We sought to identify the availability and accuracy of data held in a national dispensing database, relative to other sources of medication history information. METHODS: For patients admitted to two acute hospitals in Ireland, a Gold Standard Pre-Admission Medication List (GSPAML) was identified and corroborated with the patient or carer. The GSPAML was compared for accuracy and availability to PAMLs from other sources, including the Health Service Executive Primary Care Reimbursement Scheme (HSE-PCRS) dispensing database. RESULTS: Some 1111 medication were assessed for 97 patients, who were median age 74 years (range 18-92 years), median four co-morbidities (range 1-9), used median 10 medications (range 3-25) and half (52%) were male. The HSE-PCRS PAML was the most accurate source compared to lists provided by the general practitioner, community pharmacist or cited in previous hospital documentation: the list agreed for 74% of the medications the patients actually used, representing complete agreement for all medications in 17% of patients. It was equally contemporaneous to other sources, but was less reliable for male than female patients, those using increasing numbers of medications and those using one or more item that was not reimbursable by the HSE. WHAT IS NEW AND CONCLUSION: The HSE-PCRS database is a relatively accurate, available and contemporaneous source of medication history information and could support acute hospital medication reconciliation.

  20. Land Use Changes of Mata Lake Using Multi-temporal Satellite Imageries

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Land use and protection has become a global hotspot. How to use land resources is an important topic for the future socio-economic sustainable development. This paper analyzes the land use changes of Mata lake of Shandong province in China, from 1985's to 2000's using multi-temporal remotely sensed data including TM in the 1985s, ETM+ in the 2000s and ancillary data such as soil use map, water map etc. The remote sensing imageries were calibrated, registered and geo-referenced, then classified by multi-source information data and remote sensing image interpretation expert system based on knowledge base. Five land use types were extracted from remote sensing imageries, that is, water body, agriculture land, rural settlement, bare land and none use land. The total precision is 80.7% and Kappa index is 0.825. The analysis result of the remote sensing showsthat during the past 15 years, water resource dropped off very promptly from 51.77 km2 to 16. 65 km2 and bare land reduced greatly more than 60% in Mata lake region. With the development of the economy and agriculture areas, more and more water body and bare land converted to agriculture land use and rural settlement areas. Since last years, the Mata lake has been affected by natural factor, human activity and increasing population. So its land use pattern greatly changed from 1985 to 2000.The information of land use changes provided scientific supports for land planning and environmental protection.

  1. Decadal changes from a multi-temporal glacier inventory of Svalbard

    Directory of Open Access Journals (Sweden)

    C. Nuth

    2013-10-01

    Full Text Available We present a multi-temporal digital inventory of Svalbard glaciers with the most recent from the late 2000s containing 33 775 km2 of glaciers covering 57% of the total land area of the archipelago. At present, 68% of the glacierized area of Svalbard drains through tidewater glaciers that have a total terminus width of ~ 740 km. The glacierized area over the entire archipelago has decreased by an average of 80 km2 a−1 over the past ~ 30 yr, representing a reduction of 7%. For a sample of ~ 400 glaciers (10 000 km2 in the south and west of Spitsbergen, three digital inventories are available from the 1930/60s, 1990 and 2007 from which we calculate average changes during 2 epochs. In the more recent epoch, the terminus retreat was larger than in the earlier epoch, while area shrinkage was smaller. The contrasting pattern may be explained by the decreased lateral wastage of the glacier tongues. Retreat rates for individual glaciers show a mix of accelerating and decelerating trends, reflecting the large spatial variability of glacier types and climatic/dynamic response times in Svalbard. Lastly, retreat rates estimated by dividing glacier area changes by the tongue width are larger than centerline retreat due to a more encompassing frontal change estimate with inclusion of lateral area loss.

  2. Decadal changes from a multi-temporal glacier inventory of Svalbard

    Directory of Open Access Journals (Sweden)

    C. Nuth

    2013-06-01

    Full Text Available We present a multi-temporal digital inventory of Svalbard glaciers with the most recent from the late 2000s containing 33 775 km2 of glaciers, or 57% of the total land area of the archipelago. At present, 68% of the glaciated area of Svalbard drains through tidewater glaciers that have a summed terminus width of ~ 740 km. The glaciated area over the entire archipelago has decreased by an average of 80 km2 a−1 over the past ~ 30 yr, representing a reduction of 7%. For a sample of ~ 400 glaciers (10 000 km2 in the south and west of Spitsbergen, three digital inventories are available from 1930/60s, 1990 and 2007 from which we calculate average changes during 2 epochs. In the more recent epoch, the terminus retreat was larger than in the earlier epoch while area shrinkage was smaller. The contrasting pattern may be explained by the decreased lateral wastage of the glacier tongues. Temporal retreat rates for individual glaciers show a mix of accelerating and decelerating trends, reflecting the large spatial variability of glacier types and climatic/dynamic response times in Svalbard. Last, retreat rates estimated by dividing glacier area changes by the tongue width are larger than centerline retreat due to a more encompassing frontal change estimate with inclusion of lateral area loss.

  3. Identification of brome grass infestations in southwest Oklahoma using multi-temporal Landsat imagery

    Science.gov (United States)

    Yan, D.; de Beurs, K.

    2013-12-01

    The extensive infestation of brome grasses (Cheatgrass, Rye brome and Japanese brome) in southwest Oklahoma imposes negative impacts on local economy and ecosystem in terms of decreasing crop and forage production and increasing fire risk. Previously proposed methodologies on brome grass detection are found ill-suitable for southwest Oklahoma as a result of similar responses of background vegetation to inter-annual variability of rainfall. In this study, we aim to identify brome grass infestations by detecting senescent brome grasses using the 2011 Cultivated Land Cover Data Sets and the difference Normalized Difference Infrared Index (NDII) derived from multi-temporal Landsat imagery. Landsat imageries acquired on May 18th and June 10th 2013 by Operational Land Imager and Enhanced Thematic Mapper plus were used. The imagery acquisition dates correspond to the peak growth and senescent time of brome grasses, respectively. The difference NDII was calculated by subtracting the NDII image acquired in May from the June NDII image. Our hypotheses is that senescent brome grasses and crop/pasture fields harvested between the two image acquisition dates can be distinguished from background land cover classes because of their increases in NDII due to decreased water absorption by senescent vegetation in the shortwave infrared region. The Cultivated Land Cover Data Sets were used to further separate senescent brome grass patches from newly harvested crop/pasture fields. Ground truth data collected during field trips in June, July and August of 2013 were used to validate the detection results.

  4. Flood Inundation Mapping in the Logone Floodplain from Multi Temporal Landsat ETM+Imagery

    Science.gov (United States)

    Jung, Hahn Chul; Alsdorf, Douglas E.; Moritz, Mark; Lee, Hyongki; Vassolo, Sara

    2011-01-01

    Yearly flooding in the Logone floodplain makes an impact on agricultural, pastoral, and fishery systems in the Lake Chad Basin. Since the flooding extent and depth are highly variable, flood inundation mapping helps us make better use of water resources and prevent flood hazards in the Logone floodplain. The flood maps are generated from 33 multi temporal Landsat Enhanced Thematic Mapper Plus (ETM+) during three years 2006 to 2008. Flooded area is classified using a short-wave infrared band whereas open water is classified by Iterative Self-organizing Data Analysis (ISODATA) clustering. The maximum flooding extent in the study area increases up to approximately 5.8K km2 in late October 2008. The study also provides strong correlation of the flooding extents with water height variations in both the floodplain and the river based on a second polynomial regression model. The water heights are from ENIVSAT altimetry in the floodplain and gauge measurements in the river. Coefficients of determination between flooding extents and water height variations are greater than 0.91 with 4 to 36 days in phase lag. Floodwater drains back to the river and to the northeast during the recession period in December and January. The study supports understanding of the Logone floodplain dynamics in detail of spatial pattern and size of the flooding extent and assists the flood monitoring and prediction systems in the catchment.

  5. Protected Area Monitoring in the Niger Delta Using Multi-Temporal Remote Sensing

    Directory of Open Access Journals (Sweden)

    Alex Okiemute Onojeghuo

    2015-10-01

    Full Text Available Despite their importance, available information on the dynamics of forest protected areas and their management in the Niger delta are insufficient. We present results showing the distribution and structure of forest landscapes across protected areas in two states (Cross River and Delta within the Niger Delta using multi-temporal remote sensing. Satellite images were classified and validated using ground data, existing maps, Google Earth, and historic aerial photographs over 1986, 2000 and 2014. The total area of forest landscape for 1986, 2000 and 2014 across the identified protected areas were 535,671 ha, 494,009 ha and 469,684 ha (Cross River and 74,631 ha, 68,470 ha and 58,824 ha (Delta respectively. The study showed annual deforestation rates for protected areas across both states from 1986 to 2000 were 0.8%. However, the overall annual deforestation rate between 2000 and 2014 was higher in Delta (1.9% compared to Cross River (0.7%. This study shows accelerated levels of forest fragmentation across protected areas in both states as a side effect of the prevalence of agricultural practices and unsupervised urbanisation. The results show the need for government intervention and policy implementation, in addition to efforts by local communities and conservation organisations in protected area management across ecologically fragile areas of Nigeria.

  6. Accuracy Assessments and Validation of an Expanded UV Irradiance Database from Satellite Total Ozone Mapping Spectrometer (TOMS)

    Science.gov (United States)

    Krotkov, N. A.; Herman, J.; Fioletov, V.; Seftor, C.; Larko, D.; Vasilkov, A.

    2004-01-01

    The TOMS UV irradiance database (1978 to 2000) has been expanded to include 5 new products (noon irradiance at 305, 310, 324, and 380 nm, and noon erythemal-weighted irradiance), in addition to the existing erythemal daily exposure, which permit direct Comparisons with ground-based measurements from UV spectrometers. Sensitivity studies are conducted to estimate uncertainties of the new TOMS UV irradiance data due to algorithm apriori assumptions. Comparisons with Brewer spectrometers as well as filter radiometers are used to review of the sources of known errors. Inability to distinguish between snow and cloud cover using only TOMS data results in large errors in estimating surface UV using snow climatology. A correction is suggested for the case when the regional snow albedo is known from an independent source. The summer-time positive bias between TOMS UV estimations and Brewer measurements can be seen at all wavelengths. This suggests the difference is not related to ozone absorption effects. We emphasize that uncertainty of boundary layer UV aerosol absorption properties remains a major source of error in modeling UV irradiance in clear sky conditions. Neglecting aerosol absorption by the present TOMS algorithm results in a positive summertime bias in clear-sky UV estimations over many locations. Due to high aerosol variability the bias is strongly site dependent. Data from UV-shadow-band radiometer and well-calibrated CIMEL sun-sky radiometer are used to quantify the bias at NASA/GSFC site in Greenbelt, MD. Recommendations are given to enable potential users to better account for local conditions by combining standard TOMS UV data with ancillary ground measurements.

  7. An Image-Based Approach for the Co-Registration of Multi-Temporal UAV Image Datasets

    OpenAIRE

    Irene Aicardi; Francesco Nex; Markus Gerke; Andrea Maria Lingua

    2016-01-01

    During the past years, UAVs (Unmanned Aerial Vehicles) became very popular as low-cost image acquisition platforms since they allow for high resolution and repetitive flights in a flexible way. One application is to monitor dynamic scenes. However, the fully automatic co-registration of the acquired multi-temporal data still remains an open issue. Most UAVs are not able to provide accurate direct image georeferencing and the co-registration process is mostly performed with the manual introduc...

  8. Sandbank and Oyster Farm Monitoring with Multi-Temporal Polarimetric SAR Data Using Four-Component Scattering Power Decomposition

    OpenAIRE

    Cheng, Tzu-Yu; Yamaguchi, Yoshio; Chen, Kun-Shan; Lee, Jong-Sen; Cui, Yi

    2013-01-01

    In this paper, a multi-temporal analysis of polarimetric synthetic aperture radar (Pol-SAR) data over the sandbank and oyster farm area is presented. Specifically, a four-component scattering model, being able to identify single bounce, double bounce, volume, and helix scattering power contributions, has been employed to retrieve information. Decomposition results of a time series RADARSAT Pol-SAR images acquired over the western Taiwan coast indicate that the coastal tide level plays a key r...

  9. Agricultural Monitoring in Northeastern Ontario, Canada, Using Multi-Temporal Polarimetric RADARSAT-2 Data

    Directory of Open Access Journals (Sweden)

    Jeffrey W. Cable

    2014-03-01

    Full Text Available The purpose of this research is to analyze how changes in acquisition time and incidence angle affect various C-band synthetic aperture radar (SAR polarimetric intensities, co-polarized phase information, polarimetric response plots and decomposition parameters for various crops typical of Northern Ontario, Canada. We examine how these parameters may be used to monitor the growth stages of five common cash crops, namely, barley (Hordeum vulgare, canola (Brassica napus, oat (Avena sativa, soybean (Glycine max and wheat (Triticum spp.. In total, nine RADARSAT-2 polarimetric images were analyzed across a 14-week period beginning in June and ending in September 2011 using two incidence angles of approximately 26° and 41°. As expected, the backscatter intensities for all targets were found to show a higher response when acquired at the steeper incidence angle (26°. All cash crop targets showed a rise and fall in backscatter response over the course of the growing season, coinciding with changing growth stages. Slight phase differences were observed for cereal crops, possibly due to one of the polarizations penetrating between the rows allowing double-bounce to occur. The polarimetric response plots and decompositions offered insight into the scattering mechanisms of each crop type, generally showing an increase in volume scattering as the crops reached maturity. Specifically, the contributions of the crops increased towards the volume scattering component and zones 4 and 2, as the crops matured in regards to the Freeman-Durden and Cloude-Pottier decompositions respectively. Overall, soybean and canola showed a more similar response in comparison to the cereal cash crops. Although the study focused on Northern Ontario, it is anticipated that these results would be relevant in investigations of multi-temporal RADARSAT-2 for agricultural zones with similar crop types.

  10. Multi-temporal and multi-source remote sensing image classification by nonlinear relative normalization

    Science.gov (United States)

    Tuia, Devis; Marcos, Diego; Camps-Valls, Gustau

    2016-10-01

    Remote sensing image classification exploiting multiple sensors is a very challenging problem: data from different modalities are affected by spectral distortions and mis-alignments of all kinds, and this hampers re-using models built for one image to be used successfully in other scenes. In order to adapt and transfer models across image acquisitions, one must be able to cope with datasets that are not co-registered, acquired under different illumination and atmospheric conditions, by different sensors, and with scarce ground references. Traditionally, methods based on histogram matching have been used. However, they fail when densities have very different shapes or when there is no corresponding band to be matched between the images. An alternative builds upon manifold alignment. Manifold alignment performs a multidimensional relative normalization of the data prior to product generation that can cope with data of different dimensionality (e.g. different number of bands) and possibly unpaired examples. Aligning data distributions is an appealing strategy, since it allows to provide data spaces that are more similar to each other, regardless of the subsequent use of the transformed data. In this paper, we study a methodology that aligns data from different domains in a nonlinear way through kernelization. We introduce the Kernel Manifold Alignment (KEMA) method, which provides a flexible and discriminative projection map, exploits only a few labeled samples (or semantic ties) in each domain, and reduces to solving a generalized eigenvalue problem. We successfully test KEMA in multi-temporal and multi-source very high resolution classification tasks, as well as on the task of making a model invariant to shadowing for hyperspectral imaging.

  11. Monitoring landslide kinematics by multi-temporal radar interferometry - the Corvara landslide case study

    Science.gov (United States)

    Thiebes, Benni; Cuozzo, Giovanni; Callegari, Mattia; Schlögel, Romy; Mulas, Marco; Corsini, Alessandro; Mair, Volkmar

    2016-04-01

    Corvara landslide in the Italian Dolomites is slow-moving landslide on which extensive research activities have been carried out since the 1990ies, including sub-surface techniques (e.g. drillings, piezometers and inclinometers), surface methods (e.g. geomorphological mapping and GPS measurements), and remote sensing techniques (e.g. multi-temporal radar interferometry (MTI), and recently amplitude-based offset-tracking and UAV-based photogrammetry). The currently active volume of Corvara landslide has been estimated to be approximately 25 million m³ with shear surfaces at depths of 40 m. Displacement velocities greatly vary spatially and temporally, with only a few cm per year in the accumulation zone, and more than 20 m per year in the highly active source zone. Autumn rainfall and spring snow melt, as well as accumulation of snow during winter have been identified as the major displacement triggering and accelerating events. The ongoing landslide movements pose a threat to the municipality of Corvara, the national road 244, extensive ski resort infrastructure and a golf course. Over the last years, the focus for monitoring the Corvara landslide was put on MTI using 16 artificial corner reflectors and on permanent and periodic differential GPS measurements. This aimed for (1) assessing the ongoing displacements of an active and complex landslide, and (2) analysing the benefits and limitations of MTI for landslide monitoring from the perspective of geomorphologists but also for administrative end-user such as civil protection and Geological surveys. Here, we present the latest results of these analyses, and report on the potential of MTI and related investigations, as well as future fields of research.

  12. Monitoring Winter Wheat Freeze Injury Using Multi-Temporal MODIS Data

    Institute of Scientific and Technical Information of China (English)

    FENG Mei-chen; YANG Wu-de; CAO Liang-liang; DING Guang-wei

    2009-01-01

    Freeze injury is an usual disaster for winter wheat in Shanxi Province,China,and monitoring freeze injury is of important economic significance.The aim of this article is to monitor and analyze the winter wheat freeze injury using remote sensmg data,to monitor the occurrence and spatial distribution of winter wheat freeze in time.as well as the severity of the damage.The winter wheat freeze injury was monitored using multi-temporal moderate-resolution imaging spectroradiometer (MODIS) data,combined with ground meteorological data and field survey data,the change of normalized difference vegetation index (NDVI) before and after freeze injury was analyzed,as well as the effect of winter wheat growth recovery rate on yield.The results showed that the NDVI of winter wheat decreased dramatically after the suffering from freeze injury,which was the prominent feature for the winter wheat freeze injury monitoring.The degrees of winter wheat freeze injury were different in the three regions,of which,Yuncheng was the worst severity and the largest freeze injury area,the severity of freeze injury correlates with the breeding stage of the winter wheat.The yield of winter wheat showed positive correlation with its growth recovery rate (r=0.659**) which can be utilized to monitor the severity of winter wheat freeze injury as well as its impact on yield.It can effectively monitor the occurrence and severity of winter wheat freeze injury using horizontal and vertical profile distribution and growth recovery rate,and provide a basis for monitoring the winter wheat freeze injury in Shanxi Province.

  13. Rice monitoring with multi-temporal and dual-polarimetric TerraSAR-X data

    Science.gov (United States)

    Koppe, Wolfgang; Gnyp, Martin L.; Hütt, Christoph; Yao, Yinkun; Miao, Yuxin; Chen, Xinping; Bareth, Georg

    2013-04-01

    This study assesses the use of TerraSAR-X data for monitoring rice cultivation in the Sanjiang Plain in Heilongjiang Province, Northeast China. The main objective is the understanding of the coherent co-polarized X-band backscattering signature of rice at different phenological stages in order to retrieve growth status. For this, multi-temporal dual polarimetric TerraSAR-X High Resolution SpotLight data (HH/VV) as well as single polarized StripMap (VV) data were acquired over the test site. In conjunction with the satellite data acquisition, a ground truth field campaign was carried out. The backscattering coefficients at HH and VV of the observed fields were extracted on the different dates and analysed as a function of rice phenology to provide a physical interpretation for the co-polarized backscatter response in a temporal and spatial manner. Then, a correlation analysis was carried out between TerraSAR-X backscattering signal and rice biomass of stem, leaf and head to evaluate the relationship with different vertical layers within the rice vegetation. HH and VV signatures show two phases of backscatter increase, one at the beginning up to 46 days after transplanting and a second one from 80 days after transplanting onwards. The first increase is related to increasing double bounce reflection from the surface-stem interaction. Then, a decreasing trend of both polarizations can be observed due to signal attenuation by increasing leaf density. A second slight increase is observed during senescence. Correlation analysis showed a significant relationship with different vertical layers at different phenological stages which prove the physical interpretation of X-band backscatter of rice. The seasonal backscatter coefficient showed that X-band is highly sensitive to changes in size, orientation and density of the dominant elements in the upper canopy.

  14. Interannual surface evolution of an Antarctic blue-ice moraine using multi-temporal DEMs

    Science.gov (United States)

    Westoby, Matthew J.; Dunning, Stuart A.; Woodward, John; Hein, Andrew S.; Marrero, Shasta M.; Winter, Kate; Sugden, David E.

    2016-06-01

    Multi-temporal and fine-resolution topographic data products are increasingly used to quantify surface elevation change in glacial environments. In this study, we employ 3-D digital elevation model (DEM) differencing to quantify the topographic evolution of a blue-ice moraine complex in front of Patriot Hills, Heritage Range, Antarctica. Terrestrial laser scanning (TLS) was used to acquire multiple topographic datasets of the moraine surface at the beginning and end of the austral summer season in 2012/2013 and during a resurvey field campaign in 2014. A complementary topographic dataset was acquired at the end of season 1 through the application of structure from motion with multi-view stereo (SfM-MVS) photogrammetry to a set of aerial photographs acquired from an unmanned aerial vehicle (UAV). Three-dimensional cloud-to-cloud differencing was undertaken using the Multiscale Model to Model Cloud Comparison (M3C2) algorithm. DEM differencing revealed net uplift and lateral movement of the moraine crests within season 1 (mean uplift ~ 0.10 m) and surface lowering of a similar magnitude in some inter-moraine depressions and close to the current ice margin, although we are unable to validate the latter. Our results indicate net uplift across the site between seasons 1 and 2 (mean 0.07 m). This research demonstrates that it is possible to detect dynamic surface topographical change across glacial moraines over short (annual to intra-annual) timescales through the acquisition and differencing of fine-resolution topographic datasets. Such data offer new opportunities to understand the process linkages between surface ablation, ice flow and debris supply within moraine ice.

  15. A novel multi-temporal approach to wet snow retrieval with Sentinel-1 images (Conference Presentation)

    Science.gov (United States)

    Marin, Carlo; Callegari, Mattia; Notarnicola, Claudia

    2016-10-01

    Snow is one of the most relevant natural water resources present in nature. It stores water in winter and releases it in spring during the melting season. Monitoring snow cover and its variability is thus of great importance for a proactive management of water-resources. Of particular interest is the identification of snowmelt processes, which could significantly support water administration, flood prediction and prevention. In the past years, remote sensing has demonstrated to be an essential tool for providing accurate inputs to hydrological models concerning the spatial and temporal variability of snow. Even though the analysis of snow pack can be conducted in the visible, near-infrared and short-wave infrared spectrum, the presence of clouds during the melting season, which may be pervasive in some parts of the World (e.g., polar regions), renders impossible the regular acquisition of information needed for the operational purposes. Therefore, the use of the microwave sensors, which signal can penetrate the clouds, can be an asset for the detection of snow proprieties. In particular, the SAR images have demonstrated to be effective and robust measurements to identify the wet snow. Among the several methods presented in the literature, the best results in wet snow mapping have been achieved by the bi-temporal change detection approach proposed by Nagler and Rott [1], or its slight improvements presented afterwards (e.g., [2]). Nonetheless, with the introduction of the Sentinel-1 by ESA, which provides free-of-charge SAR images every 6 days over the same geographical area with a resolution of 20m, the scientists have the opportunity to better investigate and improve the state-of-the-art methods for wet snow detection. In this work, we propose a novel method based on a supervised learning approach able to exploit both the experience of the state-of-the-art algorithms and the high multi-temporal information provided by the Sentinel-1 data. In detail, this is done

  16. Quantification and correction of the error due to limited PIV resolution on the accuracy of non-intrusive spatial pressure measurement using a DNS channel flow database

    Science.gov (United States)

    Liu, Xiaofeng; Siddle-Mitchell, Seth

    2016-11-01

    The effect of the subgrid-scale (SGS) stress due to limited PIV resolution on pressure measurement accuracy is quantified using data from a direct numerical simulation database of turbulent channel flow (JHTDB). A series of 2000 consecutive realizations of sample block data with 512x512x49 grid nodal points were selected and spatially filtered with a coarse 17x17x17 and a fine 5x5x5 box averaging, respectively, giving rise to corresponding PIV resolutions of roughly 62.6 and 18.4 times of the viscous length scale. Comparison of the reconstructed pressure at different levels of pressure gradient approximation with the filtered pressure shows that the neglect of the viscous term leads to a small but noticeable change in the reconstructed pressure, especially in regions near the channel walls. As a contrast, the neglect of the SGS stress results in a more significant increase in both the bias and the random errors, indicating the SGS term must be accounted for in PIV pressure measurement. Correction using similarity SGS modeling reduces the random error due to the omission of SGS stress from 114.5% of the filtered pressure r.m.s. fluctuation to 89.1% for the coarse PIV resolution, and from 66.5% to 35.9% for the fine PIV resolution, respectively, confirming the benefit of the error compensation method and the positive influence of increasing PIV resolution on pressure measurement accuracy improvement.

  17. Mapping tropical forests and deciduous rubber plantations in Hainan Island, China by integrating PALSAR 25-m and multi-temporal Landsat images

    Science.gov (United States)

    Chen, Bangqian; Li, Xiangping; Xiao, Xiangming; Zhao, Bin; Dong, Jinwei; Kou, Weili; Qin, Yuanwei; Yang, Chuan; Wu, Zhixiang; Sun, Rui; Lan, Guoyu; Xie, Guishui

    2016-08-01

    Updated and accurate maps of tropical forests and industrial plantations, like rubber plantations, are essential for understanding carbon cycle and optimal forest management practices, but existing optical-imagery-based efforts are greatly limited by frequent cloud cover. Here we explored the potential utility of integrating 25-m cloud-free Phased Array type L-band Synthetic Aperture Radar (PALSAR) mosaic product and multi-temporal Landsat images to map forests and rubber plantations in Hainan Island, China. Based on structure information detected by PALSAR and yearly maximum Normalized Difference Vegetation Index (NDVI), we first identified and mapped forests with a producer accuracy (PA) of 96% and user accuracy (UA) of 98%. The resultant forest map showed reasonable spatial and areal agreements with the optical-based forest maps of Fine Resolution Observation and Monitoring Global Land Clover (FROM-GLC) and GlobalLand30. We then extracted rubber plantations from the forest map according to their deciduous features (using minimum Land Surface Water Index, LSWI) and rapid changes in canopies during Rubber Defoliation and Foliation (RDF) period (using standard deviation of LSWI) and dense canopy in growing season (using maximum NDVI). The rubber plantation map yielded a high accuracy when validated by ground truth-based data (PA/UA > 86%) and evaluated with three farm-scale rubber plantation maps (PA/UA >88%). It is estimated that in 2010, Hainan Island had 2.11 × 106 ha of forest and 5.15 × 105 ha of rubber plantations. This study has demonstrated the potential of integrating 25-m PALSAR-based structure information, and Landsat-based spectral and phenology information for mapping tropical forests and rubber plantations.

  18. Built-up Area Change Analysis in Hanoi Using Support Vector Machine Classification of Landsat Multi-Temporal Image Stacks and Population Data

    Directory of Open Access Journals (Sweden)

    Duong H. Nong

    2015-12-01

    Full Text Available In 1986, the Government of Vietnam implemented free market reforms known as Doi Moi (renovation that provided private ownership of farms and companies, and encouraged deregulation and foreign investment. Since then, the economy of Vietnam has achieved rapid growth in agricultural and industrial production, construction and housing, and exports and foreign investments, each of which have resulted in momentous landscape transformations. One of the most evident changes is urbanization and an accompanying loss of agricultural lands and open spaces. These rapid changes pose enormous challenges for local populations as well as planning authorities. Accurate and timely data on changes in built-up urban environments are essential for supporting sound urban development. In this study, we applied the Support Vector Machine classification (SVM to multi-temporal stacks of Landsat Thematic Mapper (TM and Enhanced Thematic Mapper Plus (ETM+ images from 1993 to 2010 to quantify changes in built-up areas. The SVM classification algorithm produced a highly accurate map of land cover change with an overall accuracy of 95%. The study showed that most urban expansion occurred in the periods 2001–2006 and 2006–2010. The analysis was strengthened by the incorporation of population and other socio-economic data. This study provides state authorities a means to examine correlations between urban growth, spatial expansion, and other socio-economic factors in order to not only assess patterns of urban growth but also become aware of potential environmental, social, and economic problems.

  19. Himalayan glaciers: understanding contrasting patterns of glacier behavior using multi-temporal satellite imagery

    Science.gov (United States)

    Racoviteanu, A.

    2014-12-01

    High rates of glacier retreat for the last decades are often reported, and believed to be induced by 20th century climate changes. However, regional glacier fluctuations are complex, and depend on a combination of climate and local topography. Furthermore, in ares such as the Hindu-Kush Himalaya, there are concerns about warming, decreasing monsoon precipitation and their impact on local glacier regimes. Currently, the challenge is in understanding the magnitude of feedbacks between large-scale climate forcing and small-scale glacier behavior. Spatio-temporal patterns of glacier distribution are still llimited in some areas of the high Hindu-Kush Himalaya, but multi-temporal satellite imagery has helped fill spatial and temporal gaps in regional glacier parameters in the last decade. Here I present a synopsis of the behavior of glaciers across the Himalaya, following a west to east gradient. In particular, I focus on spatial patterns of glacier parameters in the eastern Himalaya, which I investigate at multi-spatial scales using remote sensing data from declassified Corona, ASTER, Landsat ETM+, Quickbird and Worldview2 sensors. I also present the use of high-resolution imagery, including texture and thermal analysis for mapping glacier features at small scale, which are particularly useful in understanding surface trends of debris-covered glaciers, which are prevalent in the Himalaya. I compare and contrast spatial patterns of glacier area and élévation changes in the monsoon-influenced eastern Himalaya (the Everest region in the Nepal Himalaya and Sikkim in the Indian Himalaya) with other observations from the dry western Indian Himalaya (Ladakh and Lahul-Spiti), both field measurements and remote sensing-based. In the eastern Himalaya, results point to glacier area change of -0.24 % ± 0.08% per year from the 1960's to the 2006's, with a higher rate of retreat in the last decade (-0.43% /yr). Debris-covered glacier tongues show thinning trends of -30.8 m± 39 m

  20. Evaluating automatic registration of UAV imagery using multi-temporal ortho images

    Science.gov (United States)

    Saur, Günter; Krüger, Wolfgang

    2016-10-01

    Accurate geo-registration of acquired imagery is an important task when using unmanned aerial vehicles (UAV) for video reconnaissance and surveillance. As an example, change detection needs accurately geo-registered images for selecting and comparing co-located images taken at different points in time. One challenge using small UAVs lies in the instable flight behavior and using low-weight cameras. Thus, there is a need to stabilize and register the UAV imagery by image processing methods since using only direct approaches based on positional information coming from a GPS and attitude and acceleration measured by an inertial measurement unit (IMU) are not accurate enough. In order to improve this direct geo-registration (or "pre-registration"), image matching techniques are applied to align the UAV imagery to geo-registered reference images. The main challenge consists in matching images taken from different sensors at different day time and seasons. In this paper, we present evaluation methods for measuring the performance of image registration algorithms w.r.t. multi-temporal input data. They are based on augmenting a set of aligned image pairs by synthetic pre-registrations to an evaluation data set including truth transformations. The evaluation characteristics are based on quantiles of transformation residuals at certain control points. For a test site, video frames of a UAV mission and several ortho images from a period of 12 years are collected and synthetic pre-registrations corresponding to real flight parameters and registration errors are computed. Two algorithms A1 and A2 based on extracting key-points with a floating point descriptor (A1) and a binary descriptor (A2) are applied to the evaluation data set. As evaluation result, the algorithm A1 turned out to perform better than A2. Using affine or Helmert transformation types, both algorithms perform better than in the projective case. Furthermore, the evaluation classifies the ortho images w

  1. Multi-temporal satellite analysis of Wilkins Ice Shelf, Antarctic Peninsula, and consequences for its stability

    Science.gov (United States)

    Rankl, Melanie; Fürst, Johannes; Helm, Veit; Humbert, Angelika; Braun, Matthias

    2016-04-01

    Antarctic Peninsula (AP) ice shelves have been affected by ice front retreat and surface lowering over the past decades. 12 major ice shelves have disintegrated or significantly retreated and have been affected by volume loss. Longterm ice shelf thinning is twice as high at western AP ice shelves than at eastern AP ice shelves. Wilkins Ice Shelf (WIS), located at the western AP, has undergone considerable ice front retreat since the 1990s. It lost ~ 5000 km² of its size since then. Surface lowering at WIS was found to be the largest at AP ice shelves between 1978 and 2008. Here, we analyze time-series of satellite data in order to assess dynamic changes of WIS following the ice front retreat between 1994 and 2010. We present multi-temporal changes in surface velocities and deduced products, such as strain rate and stress regimes. Surface flow was derived from SAR intensity offset tracking applied to ALOS PALSAR image pairs. In addition, we show variations in ice thickness between 2003 and 2012 derived from TanDEM-X satellite acquisitions and altimetry datasets (CryoSAT-2, ICESat). The bistatic TanDEM-X acquisitions are very suitable for interferometric processing due to highly coherent image pairs. The results showed surface velocity speed up during break-up of an ice bridge between two confining islands in 2006-2008, when an area of ~ 1800 km² broke off. A sharp transition between compressive and extensive in-flow strain rates evolved at the narrowest part of the ice bridge, which contributed to the formation of a crack and hence, failure of the ice bridge in April 2009. First principal stresses were estimated to amount to ~ 250 kPa in the vicinity of the crack formation. The imaging TanDEM-X radar geometry allowed for a comprehensive ice thickness mapping of the ice shelf in 2012 and resolved many details due to the high spatial resolution. The ice thickness at WIS was found to be very heterogeneous. Thickness changes between 2003 and 2012 revealed increased

  2. Use of a multi-temporal grid method to analyze changes in glacier coverage in the Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    Qinghua Ye; Feng Chen; Alfred Stein; Zhenwei Zhong

    2009-01-01

    This paper describes a multi-temporal grid method for quantifying changes in glacier coverage. A multi-temporal grid synthesizes spatial, attribute and process components of glacier information by sequentially combining spatial data from satellite images or maps. It enables us to identify glacier retreat and advance areas in individual grid cells for three or more periods of data sets. Discrepancies among the sequential data sets were detected graphically and numerically, including noise from geo-location error, misclassification, or different interpretation results in various pixel resolutions. Noise was detected and corrected to a large extent by visualization of the synthetic grid. The paper compares the results with that from a common method based on individual data sets, focusing on the Mr. Naimona'Nyi and Mt. Qomolangrna regions at the northern slopes of the Himalayas. Results show that the identified noise (e.g. by 2.5 km2 in the Mt. Naimona'Nyi region) is much larger than measurement uncertainty calculated by sensor resolution and co-regis-tration error (e.g. by 0.015 km2 in the Mt. Naimona'Nyi region). After noise removal, we notice that glacier recession clearly accelerates. The multi-temporal grid method results in a better quantification of glacier variation. It shows that glaciers in the Himalayas have both retreated and advanced during the last several decades, with retreat dominating and accelerating. Glaciers on the northern slope of Mt.Qomolangma in the middle Himalayas retreat more extensively and faster than those in the Mt. Naimona'Nyi region in the western Himalayas.

  3. Analyzing dune dynamics at the dune-field scale based on multi-temporal analysis of Landsat-TM images

    OpenAIRE

    Mohamed, I.N.L.; Verstraeten, G.

    2012-01-01

    Studying dune dynamics at the dune-field scale requires intensive fieldwork and a relatively huge dataset. However, this is not always possible with the high cost and the limited availability of data. Here, we present a technique based on the analysis of multi-temporal Landsat-TM images for studying the dynamics of different dune morphologies from five dune-field sites around the world. A pair of Landsat-TM images for each site has been used after performing several steps of image pre-process...

  4. Object-Based Land Use Classification of Agricultural Land by Coupling Multi-Temporal Spectral Characteristics and Phenological Events in Germany

    Science.gov (United States)

    Knoefel, Patrick; Loew, Fabian; Conrad, Christopher

    2015-04-01

    Crop maps based on classification of remotely sensed data are of increased attendance in agricultural management. This induces a more detailed knowledge about the reliability of such spatial information. However, classification of agricultural land use is often limited by high spectral similarities of the studied crop types. More, spatially and temporally varying agro-ecological conditions can introduce confusion in crop mapping. Classification errors in crop maps in turn may have influence on model outputs, like agricultural production monitoring. One major goal of the PhenoS project ("Phenological structuring to determine optimal acquisition dates for Sentinel-2 data for field crop classification"), is the detection of optimal phenological time windows for land cover classification purposes. Since many crop species are spectrally highly similar, accurate classification requires the right selection of satellite images for a certain classification task. In the course of one growing season, phenological phases exist where crops are separable with higher accuracies. For this purpose, coupling of multi-temporal spectral characteristics and phenological events is promising. The focus of this study is set on the separation of spectrally similar cereal crops like winter wheat, barley, and rye of two test sites in Germany called "Harz/Central German Lowland" and "Demmin". However, this study uses object based random forest (RF) classification to investigate the impact of image acquisition frequency and timing on crop classification uncertainty by permuting all possible combinations of available RapidEye time series recorded on the test sites between 2010 and 2014. The permutations were applied to different segmentation parameters. Then, classification uncertainty was assessed and analysed, based on the probabilistic soft-output from the RF algorithm at the per-field basis. From this soft output, entropy was calculated as a spatial measure of classification uncertainty

  5. Analisis Transisi Lahan di Kabupaten Gunungkidul dengan Citra Penginderaan Jauh Multi Temporal

    Directory of Open Access Journals (Sweden)

    Wahyu Wardhana

    2015-02-01

    Full Text Available Kabupaten Gunungkidul dulu terkenal tandus kering gersang pada tahun 1940-1970-an tetapi kini telah menjadi hijau kembali. Proses ini disebut dengan proses transisi. Penelitian ini memberikan bukti empirik melalui alat bantu analisis perubahan spasial dan penginderaan jauh yang hasilnya kemudian digunakan untuk memodelkan proses tahapan transisi sebagaimana model menurut Mather (1992 dan Hosunuma (2002. Tahapan transisi saat ini menurut model tersebut adalah menuju tahap akhir dari proses pertumbuhan. Yang unik dari proses transisi di wilayah ini adalah model penutupan/penggunaan lahan yang dominan dengan bentuk pemukiman/pekarangan, sawah tadah hujan dan tegalan/ladang (sesuai SNI 7645-2010. Model ini dapat dikatakan merupakan model penyusun ekosistem baru yang terjadi dalam proses transisi yang berbeda dari model penutupan sebelumnya yang berupa hutan campuran sebagaimana dijelaskan oleh Nibbering (1991. Model ini merupakan bentuk kompromi sosial-ekologis hasil proses rehabilitasi saat itu yang dilakukan baik oleh masyarakat maupun oleh Pemerintah Daerah dengan program INPRES Penghijauan dari Pemerintah Pusat saat itu. Pembelajaran yang menarik dari proses transisi adalah kembalinya lahan bervegetasi menjadi sebuah ekosistem baru di Gunungkidul melalui dominasi penutupan/penggunaan lahan pemukiman (pekarangan, sawah tadah hujan dan tegalan/ladang. Bentuk-bentuk ini merupakan proses kompromi yang menjadi faktor keberhasilan rehabilitasi yang dilakukan saat itu. Katakunci: Gunungkidul, transisi hutan, rehabilitasi, perubahan spasial, penginderaan jauh   Analysis on the Land Transition in Gunungkidul using Multi Temporal Remote Sensing Abstract Gunungkidul was well known as barren area during 1940-1970 but now becomes fully vegetated. This process called the transition process. This study provided empirical evidences by spatial changes and remote sensing analysis and then the results were used for modelling of  the transition phases according

  6. Modelling of trail degradation based on detailed multi-temporal digital elevation models

    Science.gov (United States)

    Tomczyk, Aleksandra; Ewertowski, Marek

    2017-04-01

    Degradation of trails adversely affects the natural environment as well as the safety and comfort of visitors. Managers of protected areas can directly impact some of the factors related to the degradation, for example, they may regulate the type of use or location of the drainage. On the other hand, they may only have an indirect impact on the other factors, e.g. through the appropriate demarcation of trails. The role of national and landscape parks is both protection of the natural environment and providing recreational opportunities. Hence, the need to obtain accurate information about the current state of the trails and the direction of their transformation is apparent. Based on multi-temporal detailed digital elevation models (DEMs) generated using topographic surveys, we proposed a simplified model of geomorphological processes which shape the surface of recreational trails. As the basis of our consideration, we adopt the idea that recreational trails and forest roads can be equated with periodic flows in the context of soil loss, transport and accumulation. Our model of trail development and degradation consists of three phases: 1) Initial phase: In this phase, anthropogenic processes play the most important role. Destroying of vegetation cover by boots and tires leads to developing of a bare trail tread which becomes vulnerable to the natural processes. When the vegetation cover is removed, soil erosion starts, hence anthropogenic processes such as trampling or damaging vegetation by tires can be regarded as preparatory processes for further development. 2) Mature phase: In this phase, natural and anthropogenic processes coexist. All areas of trail tread and its surrounding undergo transformations. Anthropogenic processes impact mainly on trail tread. Trampling leads to soil compaction in case of smooth tread or to soil relocation and loss in case of bumpy tread. Uses of hiking sticks also lead to soil loosening, similar to tires of cycles. Loosening by

  7. Multi-temporal mapping of a large, slow-moving earth flow for kinematic interpretation

    Science.gov (United States)

    Guerriero, Luigi; Coe, Jeffrey A.; Revellino, Paola; Guadagno, Francesco M.

    2014-01-01

    lowest in the upper and lower parts. As the velocity of movement initiated and increased, stretching of the earth flow body induced the formation of normal faults. Conversely, decreasing velocity and shortening of the earth flow induced the formation of thrust faults. A zone with relatively few structures, bounded by strike-slip faults, was located between stretching and shortening areas. These kinematic elements indicate that the overall earth flow was actually composed of numerous linked internal earth flows, with each internal flow having a distinct pattern of structures representative of stretching and shortening (Guerriero et al., in review). These observations indicated that the spatial variation in movement velocity associated with each internal earth flow, mimicked the pattern of movement for the overall earth flow. That is, the earth flow displayed a self-similar pattern at different scales. Furthermore, the presence of other structures such as back-tilted surfaces, flank-ridges, and hydrological elements provide specific information about the shape of the basal topographic surface. Our multi-temporal maps provided a basis for interpretation of the long-term kinematic evolution of the earth flow and the influence of the basal-slip surface on the earth flow movement. Our maps showed that main faults remained stationary through time, despite extensive mobilization and movement of material. This observation indicated that the slip-surface has remained relatively stationary since at least 1954.

  8. A co-training, mutual learning approach towards mapping snow cover from multi-temporal high-spatial resolution satellite imagery

    Science.gov (United States)

    Zhu, Liujun; Xiao, Pengfeng; Feng, Xuezhi; Zhang, Xueliang; Huang, Yinyou; Li, Chengxi

    2016-12-01

    High-spatial and -temporal resolution snow cover maps for mountain areas are needed for hydrological applications and snow hazard monitoring. The Chinese GF-1 satellite is potential to provide such information with a spatial resolution of 8 m and a revisit of 4 days. The main challenge for the extraction of multi-temporal snow cover from high-spatial resolution images is that the observed spectral signature of snow and snow-free areas is non-stationary in both spatial and temporal domains. As a result, successful extraction requires adequate labelled samples for each image, which is difficult to be achieved. To solve this problem, a semi-supervised multi-temporal classification method for snow cover extraction (MSCE) is proposed. This method extends the co-training based algorithms from single image classification to multi-temporal ones. Multi-temporal images in MSCE are treated as different descriptions of the same land surface, and consequently, each pixel has multiple sets of features. Independent classifiers are trained on each feature set using a few labelled samples, and then, they are iteratively re-trained in a mutual learning way using a great number of unlabelled samples. The main principle behind MSCE is that the multi-temporal difference of land surface in spectral space can be the source of mutual learning inspired by the co-training paradigm, providing a new strategy to deal with multi-temporal image classification. The experimental findings of multi-temporal GF-1 images confirm the effectiveness of the proposed method.

  9. On the Added Value of Quad-Pol Data in a Multi-Temporal Crop Classification Framework Based on RADARSAT-2 Imagery

    Directory of Open Access Journals (Sweden)

    Arantzazu Larrañaga

    2016-04-01

    Full Text Available Polarimetric SAR images are a rich data source for crop mapping. However, quad-pol sensors have some limitations due to their complexity, increased data rate, and reduced coverage and revisit time. The main objective of this study was to evaluate the added value of quad-pol data in a multi-temporal crop classification framework based on SAR imagery. With this aim, three RADARSAT-2 scenes were acquired between May and June 2010. Once we analyzed the separability and the descriptive analysis of the features, an object-based supervised classification was performed using the Random Forests classification algorithm. Classification results obtained with dual-pol (VV-VH data as input were compared to those using quad-pol data in different polarization bases (linear H-V, circular, and linear 45°, and also to configurations where several polarimetric features (Pauli and Cloude–Pottier decomposition features and co-pol coherence and phase difference were added. Dual-pol data obtained satisfactory results, equal to those obtained with quad-pol data (in H-V basis in terms of overall accuracy (0.79 and Kappa values (0.69. Quad-pol data in circular and linear 45° bases resulted in lower accuracies. The inclusion of polarimetric features, particularly co-pol coherence and phase difference, resulted in enhanced classification accuracies with an overall accuracy of 0.86 and Kappa of 0.79 in the best case, when all the polarimetric features were added. Improvements were also observed in the identification of some particular crops, but major crops like cereals, rapeseed, and sunflower already achieved a satisfactory accuracy with the VV-VH dual-pol configuration and obtained only minor improvements. Therefore, it can be concluded that C-band VV-VH dual-pol data is almost ready to be used operationally for crop mapping as long as at least three acquisitions in dates reflecting key growth stages representing typical phenology differences of the present crops are

  10. Monitoring land subsidence process in the urban area of Ho Chi Minh city, Vietnam using multi-temporal SAR Interferometry

    Science.gov (United States)

    Nguyen, Xuan; Chang, Chung-Pai; Le, Tuan

    2016-04-01

    Land subsidence has become the most common hazard in urban area that could led to cracking buildings and infrastructures, extending the flooding area or even change the river path. Despite deriving precise information, conventional subsidence monitoring techniques are considered as costly, man-power consuming and lack of comprehensive information. Recently, SAR Interferometry (InSAR) has become a widely used geodetic technique for monitoring the deformation of the Earth's surface, especially methods based on the use of a multi-temporal dataset. In this study, we use a stack of 18 SAR images acquired from L-band PALSAR sensor onboard the ALOS satellite to derive the subsidence information of Ho Chi Minh city, Vietnam over the period of December 2006 to December 2010. The Stanford Method for Persistent Scatterers (StaMPS) Multi-Temporal Interferometry (MTI) approach is chosen to take advantages of both the persistent scatterers and the distributed scatterers, which could be used as monitoring points to measure the subsidence process. Assume the subsidence in this area mostly corresponds to vertical components, we found subsidence patterns along Saigon river and in the South of the city. Maximum subsidence rate reaches up to -66 mm/year in vertical direction. Finally, InSAR derived result and previous levelling data are taken into comparison to find the correlation between the two results.

  11. Flood monitoring and damage assessment in Thailand using multi-temporal HJ-1A/1B and MODIS images

    Science.gov (United States)

    Zhou, S. L.; Zhang, W. C.

    2017-02-01

    Flood is one of the most serious natural disasters in South Asia. How to monitor floods and assess damage caused is the most urgent problem for the government and disaster experts. With the advances of remote sensing, images acquired before the beginning of disaster to the very end or after the disaster from Earth-observing satellites benefit the decision making for reduction and protection of disaster dramatically. By using multi-temporal HJ-1A/1B and MODIS remote sensing data, applicability of different algorithms for flood monitoring and damage assessing was investigated in 2011 Thailand floods. Three different algorithms were adopted to monitor flood disaster events with water indices. Comparisons on the flood disaster monitoring and damage assessing by means of HJ-1A/1B and MODIS images suggested that multi-temporal HJ-1A/1B is much useful for the purpose, which demonstrated with the analysis of the thresholds estimated and problems in data post-processing. The variations of the inundated areas in the process of 2011 Thailand floods revealed were presented in this paper, and the damage caused by flooding was evaluated in three aspects, the population in the inundated region, the inundated information of different provinces and land use areas. Compared with MODIS, HJ-1A/1B images can provide more rapid and accurate flood extent and damage assessment for the disaster prevention, damage mitigation and disaster relief.

  12. A novel approach to co registering multi-temporal remotely sensed data in a vulnerability monitoring framework

    Science.gov (United States)

    Harb, Mostapha; De Vecchi, Daniele; Dell'Acqua, Fabio

    2014-05-01

    The paper introduces a novel approach for the geometric co registration of optical remote sensing imagery. In the context of disaster mitigation and preparedness, a multi-temporal set of several remote sensing images often has to be processed separately to extract the required information. Then, a comparison among the obtained results would provide clues towards the time-evolving extent and distribution of risk. Therefore, it is of significant importance to achieve a proper geometric matching among the compared images. The traditional procedure of using manually-determined ground control points is not viable for large stacks of images, and automated methods may fail short of ensuring image conformity. The established method uses image data itself to effectively perform the co registration among the images relying on feature extraction and matching, without the necessity of using ground control points (GCPs). The approach has been tested using both high and medium resolution images on different test cases in a context of multi-risk vulnerability monitoring. The obtained results were highly promising in resolving the mismatching problem of objects in images taken from different dates and allowing smooth extraction of vulnerability proxies from multi-temporal moderate resolution optical satellite images. In conclusion, the methodology would be a useful contribution towards easing the tracking of temporal variation of ground features in the wide domain of risk-related application of remote sensing (e.g. urban development, deforestation, wild fire, damage assessment...) Keywords: Risk monitoring, remote sensing, optical imagery, geometric co registration

  13. Application of multi-temporal landform analysis in landslide susceptibility assessment for mountainous highway - a case study in southeastern Taiwan

    Science.gov (United States)

    Liu-Xuan, Jian; Wei-Kai, Huang; Po-Shen, Lin

    2016-04-01

    This study divided a coastal mountainous highway into small sections with slope unit, plot the multi-temporal landslide inventories, and analyze the relationships between the revegetation areas of the existing landslide and newly activated landslide to calculate landslide status Index (LSI). The RI represents the multi-temporal status of landslide status in each slope unit; three statuses and their representing colors were defined in this study. Red representing slope unit with continuously landslides, yellow for those with previous landslide but stable and revegetating, green are those without landslides. The regression lines became one of the parameters in establishing landslide status map. The study area, 407K to 439K of Provincial Highway No. 9, located in southeastern Taiwan and is the most important transport corridor connecting southern Taiwan and the east coast. In 2009 this mountainous highway was hit by Typhoon Morakot and several landslides, debris slides were triggered in the study area. The debris blocked the traffic and residential communities alone the highway became isolated. To this date some section of the highway still suffer from landslide hazard and transportation had to be temporarily interrupted during some occasions. The landslide status map of this transport corridor was established combining the result of field investigation, remote sensing interpretation, and the regression lines of LSI. The preliminary result shows that out of the 258 slope units, 13 (5%) showing continuous landslides, 44 (17%) became stable and revegetating. The result of this study could provide better information for mountainous highway safety management.

  14. Change Detection Research Based on Multi-Temporal and Multi-Polarization PALSAR Data

    Science.gov (United States)

    Zhang, Wangfei; Chen, Erxue; Li, Zengyuan; Feng, Qi; Zhao, Lei

    2016-08-01

    DEM Differential Method is an effective and efficient way for forest tree height assessment with Polarimetric and interferometric technology, however, the assessment accuracy of it is based on the accuracy of interferometric results and DEM. Terra-SAR/TanDEM-X, which established the first spaceborne bistatic interferometer, can provide highly accurate cross-track interferometric images in the whole global without inherent accuracy limitations like temporal decorrelation and atmospheric disturbance. These characters of Terra-SAR/TandDEM-X give great potential for global or regional tree height assessment, which have been constraint by the temporal decorrelation in traditional repeat-pass interferometry. Currently, in China, it will be costly to collect high accurate DEM with Lidar. At the same time, it is also difficult to get truly representative ground survey samples to test and verify the assessment results. In this paper, we analyzed the feasibility of using TerraSAR/TanDEM-X data to assess forest tree height with current free DEM data like ASTER-GDEM and archived ground in-suit data like forest management inventory data (FMI). At first, the accuracy and of ASTER-GDEM and forest management inventory data had been assessment according to the DEM and canopy height model (CHM) extracted from Lidar data. The results show the average elevation RMSE between ASTER-GEDM and Lidar-DEM is about 13 meters, but they have high correlation with the correlation coefficient of 0.96. With a linear regression model, we can compensate ASTER-GDEM and improve its accuracy nearly to the Lidar-DEM with same scale. The correlation coefficient between FMI and CHM is 0.40. its accuracy is able to be improved by a linear regression model withinconfidence intervals of 95%. After compensation of ASTER-GDEM and FMI, we calculated the tree height in Mengla test site with DEM Differential Method. The results showed that the corrected ASTER-GDEM can effectively improve the assessment accuracy

  15. Efficiency and accuracy of per-field classification for operational crop mapping

    NARCIS (Netherlands)

    Wit, de A.J.W.; Clevers, J.G.P.W.

    2004-01-01

    A crop map of The Netherlands was created using a methodology that integrates multi-temporal and multi-sensor satellite imagery, statistical data on crop area and parcel boundaries from a 1 : 10 000 digital topographic map. In the first phase a crop field database was created by extracting static pa

  16. Simple luminosity normalization of greenness, yellowness and redness/greenness for comparison of leaf spectral profiles in multi-temporally acquired remote sensing images

    Indian Academy of Sciences (India)

    Ryoichi Doi

    2012-09-01

    Observation of leaf colour (spectral profiles) through remote sensing is an effective method of identifying the spatial distribution patterns of abnormalities in leaf colour, which enables appropriate plant management measures to be taken. However, because the brightness of remote sensing images varies with acquisition time, in the observation of leaf spectral profiles in multi-temporally acquired remote sensing images, changes in brightness must be taken into account. This study identified a simple luminosity normalization technique that enables leaf colours to be compared in remote sensing images over time. The intensity values of green and yellow (green+red) exhibited strong linear relationships with luminosity (R2 > 0.926) when various invariant rooftops in Bangkok or Tokyo were spectral-profiled using remote sensing images acquired at different time points. The values of the coefficient and constant or the coefficient of the formulae describing the intensity of green or yellow were comparable among the single Bangkok site and the two Tokyo sites, indicating the technique’s general applicability. For single rooftops, the values of the coefficient of variation for green, yellow, and red/green were 16% or less (n=6−11), indicating an accuracy not less than those of well-established remote sensing measures such as the normalized difference vegetation index. After obtaining the above linear relationships, raw intensity values were normalized and a temporal comparison of the spectral profiles of the canopies of evergreen and deciduous tree species in Tokyo was made to highlight the changes in the canopies’ spectral profiles. Future aspects of this technique are discussed herein.

  17. Cropping Pattern Detection and Change Analysis in Central Luzon, Philippines Using Multi-Temporal MODIS Imagery and Artificial Neural Network Classifier

    Science.gov (United States)

    dela Torre, D. M.; Perez, G. J. P.

    2016-12-01

    Cropping practices in the Philippines has been intensifying with greater demand for food and agricultural supplies in view of an increasing population and advanced technologies for farming. This has not been monitored regularly using traditional methods but alternative methods using remote sensing has been promising yet underutilized. This study employed multi-temporal data from MODIS and neural network classifier to map annual land use in agricultural areas from 2001-2014 in Central Luzon, the primary rice growing area of the Philippines. Land use statistics derived from these maps were compared with historical El Nino events to examine how land area is affected by drought events. Fourteen maps of agricultural land use was produced, with the primary classes being single-cropping, double-cropping and perennial crops with secondary classes of forests, urban, bare, water and other classes. Primary classes were produced from the neural network classifier while secondary classes were derived from NDVI threshold masks. The overall accuracy for the 2014 map was 62.05% and a kappa statistic of 0.45. 155.56% increase in single-cropping systems from 2001 to 2014 was observed while double cropping systems decreased by 14.83%. Perennials increased by 76.21% while built-up areas decreased by 12.22% within the 14-year interval. There are several sources of error including mixed-pixels, scale-conversion problems and limited ground reference data. An analysis including El Niño events in 2004 and 2010 demonstrated that marginally irrigated areas that usually planted twice in a year resorted to single cropping, indicating that scarcity of water limited the intensification allowable in the area. Findings from this study can be used to predict future use of agricultural land in the country and also examine how farmlands have responded to climatic factors and stressors.

  18. Simple luminosity normalization of greenness, yellowness and redness/greenness for comparison of leaf spectral profiles in multi-temporally acquired remote sensing images.

    Science.gov (United States)

    Doi, Ryoichi

    2012-09-01

    Observation of leaf colour (spectral profiles) through remote sensing is an effective method of identifying the spatial distribution patterns of abnormalities in leaf colour, which enables appropriate plant management measures to be taken. However, because the brightness of remote sensing images varies with acquisition time, in the observation of leaf spectral profiles in multi-temporally acquired remote sensing images, changes in brightness must be taken into account. This study identified a simple luminosity normalization technique that enables leaf colours to be compared in remote sensing images over time. The intensity values of green and yellow (green+red) exhibited strong linear relationships with luminosity (R2 greater than 0.926) when various invariant rooftops in Bangkok or Tokyo were spectralprofiled using remote sensing images acquired at different time points. The values of the coefficient and constant or the coefficient of the formulae describing the intensity of green or yellow were comparable among the single Bangkok site and the two Tokyo sites, indicating the technique's general applicability. For single rooftops, the values of the coefficient of variation for green, yellow, and red/green were 16% or less (n=6-11), indicating an accuracy not less than those of well-established remote sensing measures such as the normalized difference vegetation index. After obtaining the above linear relationships, raw intensity values were normalized and a temporal comparison of the spectral profiles of the canopies of evergreen and deciduous tree species in Tokyo was made to highlight the changes in the canopies' spectral profiles. Future aspects of this technique are discussed herein.

  19. An Improved Method for Producing High Spatial-Resolution NDVI Time Series Datasets with Multi-Temporal MODIS NDVI Data and Landsat TM/ETM+ Images

    Directory of Open Access Journals (Sweden)

    Yuhan Rao

    2015-06-01

    Full Text Available Due to technical limitations, it is impossible to have high resolution in both spatial and temporal dimensions for current NDVI datasets. Therefore, several methods are developed to produce high resolution (spatial and temporal NDVI time-series datasets, which face some limitations including high computation loads and unreasonable assumptions. In this study, an unmixing-based method, NDVI Linear Mixing Growth Model (NDVI-LMGM, is proposed to achieve the goal of accurately and efficiently blending MODIS NDVI time-series data and multi-temporal Landsat TM/ETM+ images. This method firstly unmixes the NDVI temporal changes in MODIS time-series to different land cover types and then uses unmixed NDVI temporal changes to predict Landsat-like NDVI dataset. The test over a forest site shows high accuracy (average difference: −0.0070; average absolute difference: 0.0228; and average absolute relative difference: 4.02% and computation efficiency of NDVI-LMGM (31 seconds using a personal computer. Experiments over more complex landscape and long-term time-series demonstrated that NDVI-LMGM performs well in each stage of vegetation growing season and is robust in regions with contrasting spatial and spatial variations. Comparisons between NDVI-LMGM and current methods (i.e., Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM, Enhanced STARFM (ESTARFM and Weighted Linear Model (WLM show that NDVI-LMGM is more accurate and efficient than current methods. The proposed method will benefit land surface process research, which requires a dense NDVI time-series dataset with high spatial resolution.

  20. Vegetation classification of East China with multi-temporal NOAA-AVHRR data

    Institute of Scientific and Technical Information of China (English)

    LI Junxiang; DA Liangjun; WANG Yujie; SONG Yongchang

    2006-01-01

    East China lies in the subtropical monsoon climatic zone and is dominated by subtropical evergreen broad-leaved forests,a unique vegetation type mainly distributed in East Asia with the largest distnbution in China.It is important to be able to monitor and estimate forest biomass and production,regional carbon storage,and global climate change impacts on these important vegetation types.In this paper,we used coarse resolution remote sensing data to identify the vegetation types in East China and developed a map of the spatial distribution of vegetation types in this region.Nineteen maximum normalized difference vegetation index(NDVI)composite images(acquisition time span of 7 months from February to August),which were derived from 10 days National Oceanographic and Atmospheric Administration(NOAA)Advanced Very High Resolution Radiometer(AVHRR)channel 1 and channel 2 observations,an unsupervised classification method,and the ISODATA algorithm were employed to identify the vegetation types.To reduce the dimensions of the dataset resulted in a total of 28 spectral clusters of land-cover of which two clusters were urban/bare soil and water,the images were processed using principal component analysis(PCA).The 26 remaining spectral clusters were merged into six vegetation types using the Chinese vegetation taxonomy system:evergreen broad-leaved forest,coniferous forest,bamboo forest,shrub-grass,aquatic vegetation,and agricultural vegetation.The spatial distribution and areal extent for the coniferous forests,shrub-grass,evergreen broad-leaved forests,and agricultural vegetation were calculated and comscale.The spatial accuracy and the area accuracy for coniferous forests,shrub-grass,evergreen broad-leaved forests,and agricultural vegetation were 79.2%,91.3%,68.2% and 95.9% and 92.1%,95.9%,63.8% and 90.5%,respectively.The spatial accuracy and area accuracy of the bamboo forest were 28.7% and 96.5%,respectively;the spatial accuracy of aquatic vegetation was 69.6%,but there

  1. Modelling above-ground carbon dynamics using multi-temporal airborne lidar: insights from a Mediterranean woodland

    Directory of Open Access Journals (Sweden)

    W. Simonson

    2015-09-01

    Full Text Available Woodlands represent highly significant carbon sinks globally, though could lose this function under future climatic change. Effective large-scale monitoring of these woodlands has a critical role to play in mitigating for, and adapting to, climate change. Mediterranean woodlands have low carbon densities, but represent important global carbon stocks due to their extensiveness and are particularly vulnerable because the region is predicted to become much hotter and drier over the coming century. Airborne lidar is already recognized as an excellent approach for high-fidelity carbon mapping, but few studies have used multi-temporal lidar surveys to measure carbon fluxes in forests and none have worked with Mediterranean woodlands. We use a multi-temporal (five year interval airborne lidar dataset for a region of central Spain to estimate above-ground biomass (AGB and carbon dynamics in typical mixed broadleaved/coniferous Mediterranean woodlands. Field calibration of the lidar data enabled the generation of grid-based maps of AGB for 2006 and 2011, and the resulting AGB change were estimated. There was a close agreement between the lidar-based AGB growth estimate (1.22 Mg ha−1 year−1 and those derived from two independent sources: the Spanish National Forest Inventory, and a~tree-ring based analysis (1.19 and 1.13 Mg ha−1 year−1, respectively. We parameterised a simple simulator of forest dynamics using the lidar carbon flux measurements, and used it to explore four scenarios of fire occurrence. Under undisturbed conditions (no fire occurrence an accelerating accumulation of biomass and carbon is evident over the next 100 years with an average carbon sequestration rate of 1.95 Mg C ha−1 year−1. This rate reduces by almost a third when fire probability is increased to 0.01, as has been predicted under climate change. Our work shows the power of multi-temporal lidar surveying to map woodland carbon fluxes and provide parameters for carbon

  2. Modelling above-ground carbon dynamics using multi-temporal airborne lidar: insights from a Mediterranean woodland

    Science.gov (United States)

    Simonson, W.; Ruiz-Benito, P.; Valladares, F.; Coomes, D.

    2016-02-01

    Woodlands represent highly significant carbon sinks globally, though could lose this function under future climatic change. Effective large-scale monitoring of these woodlands has a critical role to play in mitigating for, and adapting to, climate change. Mediterranean woodlands have low carbon densities, but represent important global carbon stocks due to their extensiveness and are particularly vulnerable because the region is predicted to become much hotter and drier over the coming century. Airborne lidar is already recognized as an excellent approach for high-fidelity carbon mapping, but few studies have used multi-temporal lidar surveys to measure carbon fluxes in forests and none have worked with Mediterranean woodlands. We use a multi-temporal (5-year interval) airborne lidar data set for a region of central Spain to estimate above-ground biomass (AGB) and carbon dynamics in typical mixed broadleaved and/or coniferous Mediterranean woodlands. Field calibration of the lidar data enabled the generation of grid-based maps of AGB for 2006 and 2011, and the resulting AGB change was estimated. There was a close agreement between the lidar-based AGB growth estimate (1.22 Mg ha-1 yr-1) and those derived from two independent sources: the Spanish National Forest Inventory, and a tree-ring based analysis (1.19 and 1.13 Mg ha-1 yr-1, respectively). We parameterised a simple simulator of forest dynamics using the lidar carbon flux measurements, and used it to explore four scenarios of fire occurrence. Under undisturbed conditions (no fire) an accelerating accumulation of biomass and carbon is evident over the next 100 years with an average carbon sequestration rate of 1.95 Mg C ha-1 yr-1. This rate reduces by almost a third when fire probability is increased to 0.01 (fire return rate of 100 years), as has been predicted under climate change. Our work shows the power of multi-temporal lidar surveying to map woodland carbon fluxes and provide parameters for carbon

  3. 支持多模推荐的多层数据库优化访问技术%Multi Database Access Technology Optimization Support Multimode Recommendation

    Institute of Scientific and Technical Information of China (English)

    李晓东; 魏惠茹

    2015-01-01

    Multi temporal attribute database reconstruction is the key technology to solve the data association database ac-cess recommendation, text information classification data reconstruction method using the traditional temporal attribute re-construction, which cannot effectively meet the multi-mode data recommended in the database environment. This paper proposes a support multimode recommendation database multi temporal attribute reconstruction technology. Multi temporal data reconstruction data structure model of database, realization of adaptive threshold optimization in the reconstruction pro-cess, calculate the transmission nodes in the data distribution in the direct trust and indirect trust value for each value, mul-timode recommended diagram structure, using adaptive threshold average mutual information method to solve the multi tem-poral attribute database, database access optimization. The simulation results show that, using the method of analysis of da-tabase multi temporal attribute data structure, effective implementation of multimode database user recommendation, im-prove the performance of database access, improve data scheduling. The universality and accuracy are improved.%为解决数据库访问中的关联数据推荐问题,进行数据库的多层时态属性重构,提高数据库访问能力.传统的数据时态属性重构技术采用文本信息特征分类重构方法,无法有效满足多模数据推荐中的数据库访问环境.提出一种支持多模推荐的数据库多层时态属性重构优化访问技术.构建数据库的多层时态数据重构数据结构模型,在重构过程中进行实现自适应阈值寻优,计算各传输节点在数据分发中自身对对方的直接信任值和间接信任值,进行多模推荐关系图构造,采用平均互信息方法求解数据库多层时态属性的自适应阈值,对数据库访问节点的彼此行为进行监控,实现数据库访问优化.仿真结果表明,采用该方法能有

  4. Mapping Winter Wheat with Multi-Temporal SAR and Optical Images in an Urban Agricultural Region

    Directory of Open Access Journals (Sweden)

    Tao Zhou

    2017-05-01

    Full Text Available Winter wheat is the second largest food crop in China. It is important to obtain reliable winter wheat acreage to guarantee the food security for the most populous country in the world. This paper focuses on assessing the feasibility of in-season winter wheat mapping and investigating potential classification improvement by using SAR (Synthetic Aperture Radar images, optical images, and the integration of both types of data in urban agricultural regions with complex planting structures in Southern China. Both SAR (Sentinel-1A and optical (Landsat-8 data were acquired, and classification using different combinations of Sentinel-1A-derived information and optical images was performed using a support vector machine (SVM and a random forest (RF method. The interference coherence and texture images were obtained and used to assess the effect of adding them to the backscatter intensity images on the classification accuracy. The results showed that the use of four Sentinel-1A images acquired before the jointing period of winter wheat can provide satisfactory winter wheat classification accuracy, with an F1 measure of 87.89%. The combination of SAR and optical images for winter wheat mapping achieved the best F1 measure–up to 98.06%. The SVM was superior to RF in terms of the overall accuracy and the kappa coefficient, and was faster than RF, while the RF classifier was slightly better than SVM in terms of the F1 measure. In addition, the classification accuracy can be effectively improved by adding the texture and coherence images to the backscatter intensity data.

  5. Multi-Temporal Investigation of Greenland Ice Sheet Snow Facies Using TanDEM-X Mission Data

    Science.gov (United States)

    Rizzoli, Paola; Martone, Michele; Brautigam, Benjamin; Rott, Helmut; Moreira, Alberto

    2016-08-01

    This paper presents the first results of the developed approach for classifying Greenland ice sheet snow facies, based on the use of interferometric TanDEM-X SAR data. Large-scale mosaics of radar backscatter and volume decorrelation, derived from the interferometric coherence, are used as input data set for applying a classification algorithm based on the c-means fuzzy clustering. The unique data set provided by TanDEM-X is particularly suitable for this analysis due to the single-pass bistatic acquisition mode which does not suffer from temporal decorrelation. The obtained results have been verified with external snow melt data. Moreover, independent multi-temporal TanDEM-X backscatter data and interferometric time series have been analyzed as well.

  6. Land Cover classification and change-detection analysis using multi-temporal remote sensed imagery and landscape metrics

    Directory of Open Access Journals (Sweden)

    Carmelo Riccardo Fichera

    2012-03-01

    Full Text Available Remote Sensing (RS data and techniques, in combination with GIS and landscape metrics, are fundamental to analyse and characterise Land Cover (LC and its changes. The case study here described, has been conducted in the area of Avellino (Southern Italy. To characterise the dynamics of changes during a fifty year period (1954÷2004, a multi-temporal set of images has been processed: aerial photos (1954, and Landsat scenes (MSS 1975, TM 1985 and 1993, ETM+ 2004. LC pattern and its changes are linked to both natural and social processes whose driving role has been clearly demonstrated in the case study: after the disastrous Irpinia earthquake (1980, specific zoning laws and urban plans have significantly addressed landscape changes.

  7. Detecting land subsidence near metro lines in the Baoshan district of Shanghai with multi-temporal interferometric synthetic aperture radar

    Institute of Scientific and Technical Information of China (English)

    Tao Li; Guoxiang Liu; Hui Lin; Rui Zhang; Hongguo Jia; Bing Yu

    2014-01-01

    Land subsidence is a major factor that affects metro line (ML) stability. In this study, an improved multi-temporal interferometric synthetic aperture radar (InSAR) (MTI) method to detect land subsidence near MLs is pre-sented. In particular, our multi-temporal InSAR method provides surface subsidence measurements with high observation density. The MTI method tracks both point-like targets and distributed targets with temporal radar back-scattering steadiness. First, subsidence rates at the point targets with low-amplitude dispersion index (ADI) values are extracted by applying a least-squared estimator on an optimized freely connected network. Second, to reduce error propagation, the pixels with high-ADI values are classified into several groups according to ADI intervals and processed using a Pearson correlation coefficient and hierarchical analysis strategy to obtain the distributed targets. Then, nonlinear subsidence components at all point-like and dis-tributed targets are estimated using phase unwrapping and spatiotemporal filtering on the phase residuals. The proposed MTI method was applied to detect land subsidence near MLs of No. 1 and 3 in the Baoshan district of Shanghai using 18 TerraSAR-X images acquired between April 21, 2008 and October 30, 2010. The results show that the mean subsidence rates of the stations distributed along the two MLs are -12.9 and -14.0 mm/year. Furthermore, three subsidence funnels near the MLs are discovered through the hierarchical analysis. The testing results demonstrate the satisfactory capacity of the proposed MTI method in pro-viding detailed subsidence information near MLs.

  8. Analysis of spatio-temporal pattern and driving force of land cover change using multi-temporal remote sensing images

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Landuse and land cover change is regarded as a good indicator that represents the impact of human activities on earth’s environment.When the large collection of multi-temporal satellite images has become available,it is possible to study a long-term historical process of land cover change.This study aims to investigate the spatio-temporal pattern and driving force of land cover change in the Pearl River Delta region in southern China,where the rapid development has been witnessed since 1980s.The fast economic growth has been associated with an accelerated expansion of urban landuse,which has been recorded by historical remote sensing images.This paper reports the method and outcome of the research that attempts to model spatio-temporal pattern of land cover change using multi-temporal satellite images.The classified satellite images were compared to detect the change from various landuse types to built-up areas.The trajectories of land cover change have then been established based on the time-series of the classified land cover classes.The correlation between the expansion of built-up areas and selected economic data has also been analysed for better understanding on the driving force of the rapid urbanisation process.The result shows that,since early 1990s,the dominant trend of land cover change has been from farmland to urban landuse.The relationship between economic growth indicator(measured by GDP)and built-up area can well fit into a linear regression model with correlation coefficients greater than 0.9.It is quite clear that cities or towns have been sprawling in general,demonstrating two growth models that were closely related to the economic development stages.

  9. An Image-Based Approach for the Co-Registration of Multi-Temporal UAV Image Datasets

    Directory of Open Access Journals (Sweden)

    Irene Aicardi

    2016-09-01

    Full Text Available During the past years, UAVs (Unmanned Aerial Vehicles became very popular as low-cost image acquisition platforms since they allow for high resolution and repetitive flights in a flexible way. One application is to monitor dynamic scenes. However, the fully automatic co-registration of the acquired multi-temporal data still remains an open issue. Most UAVs are not able to provide accurate direct image georeferencing and the co-registration process is mostly performed with the manual introduction of ground control points (GCPs, which is time consuming, costly and sometimes not possible at all. A new technique to automate the co-registration of multi-temporal high resolution image blocks without the use of GCPs is investigated in this paper. The image orientation is initially performed on a reference epoch and the registration of the following datasets is achieved including some anchor images from the reference data. The interior and exterior orientation parameters of the anchor images are then fixed in order to constrain the Bundle Block Adjustment of the slave epoch to be aligned with the reference one. The study involved the use of two different datasets acquired over a construction site and a post-earthquake damaged area. Different tests have been performed to assess the registration procedure using both a manual and an automatic approach for the selection of anchor images. The tests have shown that the procedure provides results comparable to the traditional GCP-based strategy and both the manual and automatic selection of the anchor images can provide reliable results.

  10. PEMETAAN DISTRIBUSI KERAMBA JARING APUNG IKAN AIR TAWAR DI WADUK CIRATA, JAWA BARAT DENGAN MULTI TEMPORAL DATA ALOS AVNIR-2

    Directory of Open Access Journals (Sweden)

    I Nyoman Radiarta

    2016-11-01

    Full Text Available Budidaya ikan air tawar dengan keramba jaring apung (KJA telah memberikan kontribusi yang cukup besar bagi peningkatan produksi perikanan, menyediakan lapangan kerja, dan perbaikan perekonomian masyarakat. Penelitian ini bertujuan untuk melakukan pemetaan distribusi keramba jaring apung ikan air tawar di Waduk Cirata, Jawa Barat. Data utama yang digunakan dalam penelitian ini adalah multi temporal data satelit Advanced Land Observing Satellite (ALOS Advance Visible and Near Infrared Radiometer type 2 (AVNIR-2 tanggal 27 Juni 2008 dan 27 September 2008. Validasi data satelit telah dilakukan melalui survei lapangan pada tanggal 17 April 2009. Hasil klasifikasikan data satelit dan estimasi luasan menunjukkan adanya peningkatan luasan KJA dari 892 ha pada bulan Juni 2008 menjadi 949 ha pada bulan September 2008, sedangkan luasan waduk menunjukkan penurunan yaitu 5.839 ha pada bulan Juni 2008 menjadi 4.818 ha pada bulan September 2008. Hasil pemetaan dan estimasi luasan dari penelitian ini berguna sebagai data dasar yang dapat dimanfaatkan untuk perencanaan dan pengelolaan waduk yang lebih baik. Freshwater cage aquaculture is of a great importance to increase aquaculture production, provide employment opportunity and improve rural economy. The aim of this study was to map the distribution of freshwater cage aquaculture in Cirata Reservoir, West Java. The main data source used in this study include a multi temporal satellite data of ALOS AVNIR-2 acquired on Juni 27, 2008 and September 27, 2008. Satellite data were validated through field visit on April 17, 2009. Based on image classification and area estimation, the results show that increasing trend of cage culture area from 892 ha in June 2008 to 949 ha in September 2008. Meanwhile, decreasing trend was observed for reservoir area: 5,839 ha in June 2008 to 4,818 ha in September 2008. Results from this study can be used as a basic information for a better planning and management of the reservoir.

  11. Predicting grain yield in rice using multi-temporal vegetation indices from UAV-based multispectral and digital imagery

    Science.gov (United States)

    Zhou, X.; Zheng, H. B.; Xu, X. Q.; He, J. Y.; Ge, X. K.; Yao, X.; Cheng, T.; Zhu, Y.; Cao, W. X.; Tian, Y. C.

    2017-08-01

    Timely and non-destructive assessment of crop yield is an essential part of agricultural remote sensing (RS). The development of unmanned aerial vehicles (UAVs) has provided a novel approach for RS, and makes it possible to acquire high spatio-temporal resolution imagery on a regional scale. In this study, the rice grain yield was predicted with single stage vegetation indices (VIs) and multi-temporal VIs derived from the multispectral (MS) and digital images. The results showed that the booting stage was identified as the optimal stage for grain yield prediction with VIs at a single stage for both digital image and MS image. And corresponding optimal color index was VARI with R2 value of 0.71 (Log relationship). While the optimal vegetation index NDVI[800,720] based on MS images showed a linear relationship with the grain yield and gained a higher R2 value (0.75) than color index did. The multi-temporal VIs showed a higher correlation with grain yield than the single stage VIs did. And the VIs at two random growth stage with the multiple linear regression function [MLR(VI)] performed best. The highest correlation coefficient were 0.76 with MLR(NDVI[800,720]) at the booting and heading stages (for the MS image) and 0.73 with MLR(VARI) at the jointing and booting stages (for the digital image). In addition, the VIs that showed a high correlation with LAI performed well for yield prediction, and the VIs composed of red edge band (720 nm) and near infrared band (800 nm) were found to be more effective in predicting yield and LAI at high level. In conclusion, this study has demonstrated that both MS and digital sensors mounted on the UAV are reliable platforms for rice growth and grain yield estimation, and determined the best period and optimal VIs for rice grain yield prediction.

  12. Combined Use of Multi-Temporal Optical and Radar Satellite Images for Grassland Monitoring

    Directory of Open Access Journals (Sweden)

    Pauline Dusseux

    2014-06-01

    Full Text Available The aim of this study was to assess the ability of optical images, SAR (Synthetic Aperture Radar images and the combination of both types of data to discriminate between grasslands and crops in agricultural areas where cloud cover is very high most of the time, which restricts the use of visible and near-infrared satellite data. We compared the performances of variables extracted from four optical and five SAR satellite images with high/very high spatial resolutions acquired during the growing season. A vegetation index, namely the NDVI (Normalized Difference Vegetation Index, and two biophysical variables, the LAI (Leaf Area Index and the fCOVER (fraction of Vegetation Cover were computed using optical time series and polarization (HH, VV, HV, VH. The polarization ratio and polarimetric decomposition (Freeman–Durden and Cloude–Pottier were calculated using SAR time series. Then, variables derived from optical, SAR and both types of remotely-sensed data were successively classified using the Support Vector Machine (SVM technique. The results show that the classification accuracy of SAR variables is higher than those using optical data (0.98 compared to 0.81. They also highlight that the combination of optical and SAR time series data is of prime interest to discriminate grasslands from crops, allowing an improved classification accuracy.

  13. Implementation of the European multicentre database of healthy controls for [(123)I]FP-CIT SPECT increases diagnostic accuracy in patients with clinically uncertain parkinsonian syndromes

    DEFF Research Database (Denmark)

    Albert, Nathalie L; Unterrainer, Marcus; Diemling, Markus

    2016-01-01

    PURPOSE: Even though [(123)I]FP-CIT SPECT provides high accuracy in detecting nigrostriatal cell loss in neurodegenerative parkinsonian syndromes (PS), some patients with an inconclusive diagnosis remain. We investigated whether the diagnostic accuracy in patients with clinically uncertain PS...

  14. Dynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR), P. R. China

    Science.gov (United States)

    Leempoel, K.; Satyaranayana, B.; Bourgeois, C.; Zhang, J.; Chen, M.; Wang, J.; Bogaert, J.; Dahdouh-Guebas, F.

    2013-08-01

    Mangrove forests are declining across the globe, mainly because of human intervention, and therefore require an evaluation of their past and present status (e.g. areal extent, species-level distribution, etc.) to implement better conservation and management strategies. In this paper, mangrove cover dynamics at Gaoqiao (P. R. China) were assessed through time using 1967, 2000 and 2009 satellite imagery (sensors Corona KH-4B, Landsat ETM+, GeoEye-1 respectively). Firstly, multi-temporal analysis of satellite data was undertaken, and secondly biotic and abiotic differences were analysed between the different mangrove stands, assessed through a supervised classification of a high-resolution satellite image. A major decline in mangrove cover (-36%) was observed between 1967 and 2009 due to rice cultivation and aquaculture practices. Moreover, dike construction has prevented mangroves from expanding landward. Although a small increase of mangrove area was observed between 2000 and 2009 (+24%), the ratio mangrove / aquaculture kept decreasing due to increased aquaculture at the expense of rice cultivation in the vicinity. From the land-use/cover map based on ground-truth data (5 × 5 m plot-based tree measurements) (August-September, 2009) as well as spectral reflectance values (obtained from pansharpened GeoEye-1), both Bruguiera gymnorrhiza and small Aegiceras corniculatum are distinguishable at 73-100% accuracy, whereas tall A. corniculatum was correctly classified at only 53% due to its mixed vegetation stands with B. gymnorrhiza (overall classification accuracy: 85%). In the case of sediments, sand proportion was significantly different between the three mangrove classes. Overall, the advantage of very high resolution satellite images like GeoEye-1 (0.5 m) for mangrove spatial heterogeneity assessment and/or species-level discrimination was well demonstrated, along with the complexity to provide a precise classification for non-dominant species (e.g. Kandelia obovata

  15. Dynamics in mangroves assessed by high-resolution and multi-temporal satellite data: a case study in Zhanjiang Mangrove National Nature Reserve (ZMNNR, P. R. China

    Directory of Open Access Journals (Sweden)

    K. Leempoel

    2013-08-01

    Full Text Available Mangrove forests are declining across the globe, mainly because of human intervention, and therefore require an evaluation of their past and present status (e.g. areal extent, species-level distribution, etc. to implement better conservation and management strategies. In this paper, mangrove cover dynamics at Gaoqiao (P. R. China were assessed through time using 1967, 2000 and 2009 satellite imagery (sensors Corona KH-4B, Landsat ETM+, GeoEye-1 respectively. Firstly, multi-temporal analysis of satellite data was undertaken, and secondly biotic and abiotic differences were analysed between the different mangrove stands, assessed through a supervised classification of a high-resolution satellite image. A major decline in mangrove cover (−36% was observed between 1967 and 2009 due to rice cultivation and aquaculture practices. Moreover, dike construction has prevented mangroves from expanding landward. Although a small increase of mangrove area was observed between 2000 and 2009 (+24%, the ratio mangrove / aquaculture kept decreasing due to increased aquaculture at the expense of rice cultivation in the vicinity. From the land-use/cover map based on ground-truth data (5 × 5 m plot-based tree measurements (August–September, 2009 as well as spectral reflectance values (obtained from pansharpened GeoEye-1, both Bruguiera gymnorrhiza and small Aegiceras corniculatum are distinguishable at 73–100% accuracy, whereas tall A. corniculatum was correctly classified at only 53% due to its mixed vegetation stands with B. gymnorrhiza (overall classification accuracy: 85%. In the case of sediments, sand proportion was significantly different between the three mangrove classes. Overall, the advantage of very high resolution satellite images like GeoEye-1 (0.5 m for mangrove spatial heterogeneity assessment and/or species-level discrimination was well demonstrated, along with the complexity to provide a precise classification for non-dominant species (e

  16. Quantification of Deltaic Coastal Zone Change Based on Multi-Temporal High Resolution Earth Observation Techniques

    Directory of Open Access Journals (Sweden)

    Emmanuel Vassilakis

    2014-01-01

    Full Text Available A series of methodologies are described in this paper aiming to quantify the natural hazard due to the coastal changes at a deltaic fan. The coastline of Istiaia (North Evia, Greece has been chosen for this study as several areas of accretion and erosion have been identified during the past few decades. We combined different types of datasets, extracted from high resolution panchromatic aerial photographs and traced the contemporary shoreline by high accuracy surveying with Real Time Kinematics (RTK GPS equipment. The interpretation of all shorelines required geo-statistical analysis in a Geographical Information System. A large number of high resolution morphological sections were constructed normally to the coast, revealing erosional and depositional parts of the beach. Retreating and extension rates were calculated for each section reaching the values of 0.98 m/yr and 1.36 m/yr, respectively. The results proved to be very accurate, allowing us to expand the developed methodology by using more complete time-series of remote sensing datasets along with more frequent RTK-GPS surveying.

  17. Changing Pattern of Crop Fraction in Late Blight Induced Potato Crops in Potato Bowl of West Bengal by using Multi-temporal Time Series AWiFs Data

    Science.gov (United States)

    Chakrabarty, Abhisek

    2016-07-01

    Crop fraction is the ratio of crop occupying a unit area in ground pixel, is very important for monitoring crop growth. One of the most important variables in crop growth monitoring is the fraction of available solar radiation intercepted by foliage. Late blight of potato (Solanum tuberosum), caused by the oomycete pathogen Phytophthora infestans, is considered to be the most destructive crop diseases of potato worldwide. Under favourable climatic conditions, and without intervention (i.e. fungicide sprays), the disease can destroy potato crop within few weeks. Therefore it is important to evaluate the crop fraction for monitoring the healthy and late blight affected potato crops. This study was conducted in potato bowl of West Bengal, which consists of districts of Hooghly, Howrah, Burdwan, Bankuara, and Paschim Medinipur. In this study different crop fraction estimation method like linear spectral un-mixing, Normalized difference vegetation index (NDVI) based DPM model (Zhang et al. 2013), Ratio vegetation index based DPM model, improved Pixel Dichotomy Model (Li et al. 2014) ware evaluated using multi-temporal IRS AWiFs data in two successive potato growing season of 2012-13 and 2013-14 over the study area and compared with measured crop fraction. The comparative study based on measured healthy and late blight affected potato crop fraction showed that improved Pixel Dichotomy Model maintain the high coefficient of determination (R2= 0.835) with low root mean square error (RMSE=0.21) whereas the correlation values of NDVI based DPM model and RVI based DPM model is 0.763 and 0.694 respectively. The changing pattern of crop fraction profile of late blight affected potato crop was studied in respect of healthy potato crop fraction which was extracted from the 269 GPS points of potato field. It showed that the healthy potato crop fraction profile maintained the normal phenological trend whereas the late blight affected potato crop fraction profile suddenly fallen

  18. Woody vegetation cover monitoring with multi-temporal Landsat data and Random Forests: the case of the Northwest Province (South Africa)

    Science.gov (United States)

    Symeonakis, Elias; Higginbottom, Thomas; Petroulaki, Kyriaki

    2016-04-01

    Land degradation and desertification (LDD) are serious global threats to humans and the environment. Globally, 10-20% of drylands and 24% of the world's productive lands are potentially degraded, which affects 1.5 billion people and reduces GDP by €3.4 billion. In Africa, LDD processes affect up to a third of savannahs, leading to a decline in the ecosystem services provided to some of the continent's poorest and most vulnerable communities. Indirectly, LDD can be monitored using relevant indicators. The encroachment of woody plants into grasslands, and the subsequent conversion of savannahs and open woodlands into shrublands, has attracted a lot of attention over the last decades and has been identified as an indicator of LDD. According to some assessments, bush encroachment has rendered 1.1 million ha of South African savanna unusable, threatens another 27 million ha (~17% of the country), and has reduced the grazing capacity throughout the region by up to 50%. Mapping woody cover encroachment over large areas can only be effectively achieved using remote sensing data and techniques. The longest continuously operating Earth-observation program, the Landsat series, is now freely-available as an atmospherically corrected, cloud masked surface reflectance product. The availability and length of the Landsat archive is thus an unparalleled Earth-observation resource, particularly for long-term change detection and monitoring. Here, we map and monitor woody vegetation cover in the Northwest Province of South Africa, a mosaic of 12 Landsat scenes that expands over more than 100,000km2. We employ a multi-temporal approach with dry-season TM, ETM+ and OLI data from 15 epochs between 1989 to 2015. We use 0.5m-pixel colour aerial photography to collect >15,000 samples for training and validating a Random Forest model to map woody cover, grasses, crops, urban and bare areas. High classification accuracies are achieved, especially so for the two cover types indirectly

  19. Multi-temporal image analysis for river reach morphological changes identification

    Science.gov (United States)

    Giordan, Daniele; Franzi, Luca; Rinaldi, Stefano; Dutto, Furio; Baldo, Marco; Allasia, Paolo

    2016-04-01

    to threatening the hamlet of Pratoregio. In 2007 the public administration (Regione Piemonte) financed the LiDAR survey on the Orco river, in collaboration with the Politecnico of Turin and the CNR-IRPI. Now, a RPAS survey of the reach nearby Pratoregio has been used to map the recent altimetric and planimetric evolution of the river, where the flood control works have been damaged by strong lateral river erosion. The RPAS dataset has been very useful to map the new shape of the river's channels to measure the volumetric changes of the river lateral bars and to obtain an updated 3D model useful for hydraulic numerical simulations. The aim of the survey is the identification of the best engineering solution tom manage the river and to protect the endangered areas. The availability of LiDAR and RPAS DSM has been also used to evaluate the accuracy of RPAS DSM and its limitations.

  20. Railway infrastructure monitoring with COSMO/SkyMed imagery and multi-temporal SAR interferometry

    Science.gov (United States)

    Chiaradia, M.; Nutricato, R.; Nitti, D. O.; Bovenga, F.; Guerriero, L.

    2012-12-01

    For all the European Countries, the rail network represents a key critical infrastructure, deserving protection in view of its continuous structure spread over the whole territory, of the high number of European citizens using it for personal and professional reasons, and of the large volume of freight moving through it. Railway system traverses a wide variety of terrains and encounters a range of geo-technical conditions. The interaction of these factors together with climatic and seismic forcing, may produce ground instabilities that impact on the safety and efficiency of rail operations. In such context, a particular interest is directed to the development of technologies regarding both the prevention of mishaps of infrastructures and the fast recovery of their normal working conditions after the occurrence of accidents (disaster managing). Both these issues are of strategic interest for EU Countries, and in particular for Italy, since, more than other countries, it is characterized by a geo-morphological and hydro-geological structure complexity that increases the risk of natural catastrophes due to landslides, overflowings and floods. The present study has been carried out in the framework of a scientific project aimed at producing a diagnostic system, capable to foresee and monitor landslide events along railway networks by integrating in situ data, detected from on board sophisticated innovative measuring systems, with Earth Observation (EO) techniques. Particular importance is devoted to the use of advanced SAR interferometry, thanks to their all-weather, day-night capability to detect and measure with sub-centimeter accuracy ground surface displacements that, in such context, can occur before a landslide event or after that movements . Special attention is directed to the use of SAR images acquired by COSMO/SkyMed (ASI) constellation capable to achieve very high spatial resolution and very short revisit and response time. In this context, a stack of 57 CSK

  1. Multi-temporal InSAR monitoring of landslides in a tropical urban environment: focus on Bukavu (DR Congo)

    Science.gov (United States)

    Nobile, Adriano; Monsieurs, Elise; Dewitte, Olivier; d'Oreyes, Nicolas; Kervyn, Francois

    2016-04-01

    The western branch of the East African Rift System, in Central Africa, is characterized by the presence of several geohazards: earthquakes, volcanoes, and landslides. Every year, landslides cause fatalities, structural and functional damage to infrastructure and private properties with serious disruptions of the organization of societies and severe impact on the populations. These impacts are particularly important in the city of Bukavu (DR Congo) located within the Rift, on the southern shore of Lake Kivu. Large slow-moving landslides continuously affect highly populated slopes in the city. However little is known about their actual kinematics and the processes at play. Here we use multi-temporal InSAR technique to monitor these ground deformations. Using 50 Cosmo-SkyMed SAR images, acquired between March - October 2015 with a revisiting time of 8 days (ascending and descending orbits), we produce displacement-rate maps and ground deformation time series using the PS technique. Movements with a velocity >5cm/yr are detected, which is consistent with field observations. DGPS measurements, taken at 21 benchmarks in the area during the same period, allow validating the results. Similar ground deformation rates are found for the period 2002-2008 using Envisat ASAR images. Furthermore, comparison with rainfall monitoring data acquire on site should help us to understand the influence of water and the tropical seasonality in the slide mechanisms.

  2. Use of multi-temporal SPOT-5 satellite images for land degradation assessment in Cameron Highlands, Malaysia using Geospatial techniques

    Science.gov (United States)

    Nampak, Haleh; Pradhan, Biswajeet

    2016-07-01

    Soil erosion is the common land degradation problem worldwide because of its economic and environmental impacts. Therefore, land-use change detection has become one of the major concern to geomorphologists, environmentalists, and land use planners due to its impact on natural ecosystems. The objective of this paper is to evaluate the relationship between land use/cover changes and land degradation in the Cameron highlands (Malaysia) through multi-temporal remotely sensed satellite images and ancillary data. Land clearing in the study area has resulted increased soil erosion due to rainfall events. Also unsustainable development and agriculture, mismanagement and lacking policies contribute to increasing soil erosion rates. The LULC distribution of the study area was mapped for 2005, 2010, and 2015 through SPOT-5 satellite imagery data which were classified based on object-based classification. A soil erosion model was also used within a GIS in order to study the susceptibility of the areas affected by changes to overland flow and rain splash erosion. The model consists of four parameters, namely soil erodibility, slope, vegetation cover and overland flow. The results of this research will be used in the selection of the areas that require mitigation processes which will reduce their degrading potential. Key words: Land degradation, Geospatial, LULC change, Soil erosion modelling, Cameron highlands.

  3. Predictive modelling of savannah woody cover: A multi-temporal and multi-sensor machine learning investigation

    Science.gov (United States)

    Higginbottom, Thomas; Symeonakis, Elias

    2016-04-01

    Effective monitoring of the Earth's ecosystems requires the availability of methods for quantifying the structural composition and cover of vegetation. This is especially important in heterogeneous environments, such as semi-arid savannahs which are naturally comprised of a dynamic mix of tree, shrub, and grass components. The fractional coverage of woody vegetation is a key ecosystem attribute in savannahs, particularly given current concerns over the invasion of grasslands by shrub species (shrub encroachment), or the over-exploitation of woody biomass for fuelwood. Remote sensing has a clear role to play in monitoring semi-arid environments, and in recent years the number of both spacebourne sensors and collected scenes has increased dramatically allowing for multi-temporal and multi-sensor investigations. Here we employ a statistical learning framework to assess the potential of optical and radar imagery for predicting fractional woody cover. We test a number of different model combinations in the Kruger National Park, South Africa. Our results show that combining Landsat and PALSAR data produces the most accurate predictions (R2 =0.65, P fractional cover prediction.

  4. The evolution of active Lavina di Roncovetro landslides by multi-temporal high-resolution topographic data

    Science.gov (United States)

    Isola, Ilaria; Fornaciai, Alessandro; Favalli, Massimiliano; Gigli, Giovanni; Nannipieri, Luca; Mucchi, Lorenzo; Intrieri, Emanuele; Pizziolo, Marco; Bertolini, Giovanni; Trippi, Federico; Casagli, Nicola; Schina, Rosa; Carnevale, Ennio

    2017-04-01

    High-resolution topographic data has been collected over the Lavina di Roncovetro active landslide (Reggio Emilia, Italy) for about 3 years by using various methods and technologies. Tha Lavina di Roncovetro landslide can be considered as a fluid-viscous mudflow, which can reach a down flow maximum rate of 10 m/day. The landslide started between the middle and the end of the XIX century and since then it has had a rapid evolution mainly characterized by the rapid retrogression of the crown to the extent that now reaches the top of Mount Staffola. In the frame of EU Wireless Sensor Network for Ground Instability Monitoring - Wi-GIM project (LIFE12ENV/IT/001033) the Lavina di Roncovetro landslide has been periodically tracked using technologies that span from the LiDAR, both terrestrial and aerial, to the Structure from Motion (SfM) photogrammetry method based on Unmanned Aerial Vehicle (UAV) and aerial survey. These data are used to create six high-resolution Digital Terrain Models (DEMs), which imaged the landslide surface on March 2014, October 2014, June 2015, July 2015, January 2016 and December 2016. Multi-temporal high-resolution topographic data have been used for qualitative and quantitative morphometric analysis and topographic change detection of the landslide with the aim to estimate and map the volume of removed and/or accumulated material, the average rates of vertical and horizontal displacement and the deformation structures affecting the landslide over the investigated period.

  5. L- and X-Band Multi-Temporal InSAR Analysis of Tianjin Subsidence

    Directory of Open Access Journals (Sweden)

    Qingli Luo

    2014-08-01

    Full Text Available When synthetic aperture radar interferometry (InSAR technology is applied in the monitoring of land subsidence, the sensor band plays an important role. An X-band SAR system as TerraSAR-X (TSX provides high resolution and short revisit time, but it has no capability of global coverage. On the other side, an L-band sensor as Advanced Land Observing Satellite-Phased Array L-band Synthetic Aperture Radar (ALOS-PALSAR has global coverage and it produces highly coherent interferograms, but it provides much less details in time and space. The characteristics of these two satellites from different bands can be regarded as complementary. In this paper, we firstly present a possible strategy for X-band optimized acquisition planning combining with L-band. More importantly, we also present the multi-temporal InSAR (MT-InSAR analysis results from 23 ALOS-PALSAR images and 37 TSX data, which show the complementarity of L- and X-band allows measuring deformations both in urban and non-urban areas. Furthermore, the validation between MT-INSAR and leveling/GPS has been carried out. The combination analysis of L- and X-band MT-InSAR results effectively avoids the limitation of X-band, providing a way to define the shape and the borderline of subsiding center and helps us to understand the subsidence mechanism. Finally, the geological interpretation of the detected subsidence center is given.

  6. Evaluation of crop yield loss of floods based on water turbidity index with multi-temporal HJ-CCD images

    Science.gov (United States)

    Gu, Xiaohe; Xu, Peng; Wang, Lei; Wang, Xiuhui

    2015-12-01

    Paddy is one of the most important food crops in China. Due to the intensive planting in the surrounding of rivers and lakes, paddy is vulnerable to flooding stress. The research on predicting crop yield loss derived from flooding stress will help the adjustment of crop planting structure and the claims of agricultural insurance. The paper aimed to develop a method of estimating yield loss of paddy derived from flooding by multi-temporal HJ CCD images. At first, the water pixels after flooding were extracted, from which the water line (WL) of turbid water pixels was generated. Secondly, the water turbidity index (WTI) and perpendicular vegetation index (PVI) was defined and calculated. By analyzing the relation among WTI, PVI and paddy yield, the model of evaluating yield loss of flooding was developed. Based on this model, the spatial distribution of paddy yield loss derived from flooding was mapped in the study area. Results showed that the water turbidity index (WTI) could be used to monitor the sediment content of flood, which was closely related to the plant physiology and per unit area yield of paddy. The PVI was the good indicator of paddy yield with significant correlation (0.965). So the PVI could be used to estimate the per unit area yield before harvesting. The PVI and WTI had good linear relation, which could provide an effective, practical and feasible method for monitoring yield loss of waterlogged paddy.

  7. Co-seismic landslide topographic analysis based on multi-temporal DEM-A case study of the Wenchuan earthquake.

    Science.gov (United States)

    Ren, Zhikun; Zhang, Zhuqi; Dai, Fuchu; Yin, Jinhui; Zhang, Huiping

    2013-01-01

    Hillslope instability has been thought to be one of the most important factors for landslide susceptibility. In this study, we apply geomorphic analysis using multi-temporal DEM data and shake intensity analysis to evaluate the topographic characteristics of the landslide areas. There are many geomorphologic analysis methods such as roughness, slope aspect, which are also as useful as slope analysis. The analyses indicate that most of the co-seismic landslides occurred in regions with roughness, hillslope and slope aspect of >1.2, >30, and between 90 and 270, respectively. However, the intersection regions from the above three methods are more accurate than that derived by applying single topographic analysis method. The ground motion data indicates that the co-seismic landslides mainly occurred on the hanging wall side of Longmen Shan Thrust Belt within the up-down and horizontal peak ground acceleration (PGA) contour of 150 PGA and 200 gal, respectively. The comparisons of pre- and post-earthquake DEM data indicate that the medium roughness and slope increased, the roughest and steepest regions decreased after the Wenchuan earthquake. However, slope aspects did not even change. Our results indicate that co-seismic landslides mainly occurred at specific regions of high roughness, southward and steep sloping areas under strong ground motion. Co-seismic landslides significantly modified the local topography, especially the hillslope and roughness. The roughest relief and steepest slope are significantly smoothed; however, the medium relief and slope become rougher and steeper, respectively.

  8. Spatial changes of estuary in Ernakulam district, Southern India for last seven decades, using multi-temporal satellite data.

    Science.gov (United States)

    Dipson, P T; Chithra, S V; Amarnath, A; Smitha, S V; Harindranathan Nair, M V; Shahin, Adhem

    2015-01-15

    The study area, located in the western side of Kerala State, South India, is a part of Vembanad-Kol wetlands - the largest estuary in India's western coastal wetland system and one of the Ramsar Sites of Kerala. Major portion of this estuary comes under the Ernakulam district which includes the Cochin City - the business and Industrial hub of Kerala, which has seen fast urbanization since independence (1947). Recently, this region is subjected to a characteristic fast urban sprawl, whereas, the estuarine zone is subjected to tremendous land use/land cover changes (LULC). Periodic monitoring of the estuary is essential for the formulation of viable management options for the sustainable utilization of this vital environmental resource. Remote sensing coupled with GIS applications has proved to be a useful tool in monitoring wetland changes. In the present study, the changes this estuarine region have undergone from 1944 to 2009 have been monitored with the help of multi-temporal satellite data. Estuarine areas were mapped with the help of Landsat MSS (1973), Landsat ETM (1990) and IRS LISS-III (1998 and 2009) using visual interpretation and digitization techniques in ArcGIS 9.3 Environment. The study shows a progressive decrease in the estuarine area, the reasons of which are identified chronologically. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Implementation of the European multicentre database of healthy controls for [{sup 123}I]FP-CIT SPECT increases diagnostic accuracy in patients with clinically uncertain parkinsonian syndromes

    Energy Technology Data Exchange (ETDEWEB)

    Albert, Nathalie L.; Unterrainer, Marcus; Xiong, Guoming; Bartenstein, Peter; Koch, Walter [University of Munich, Department of Nuclear Medicine, Munich (Germany); Diemling, Markus [Hermes Medical Solutions, Stockholm (Sweden); Varrone, Andrea [Karolinska University Hospital, Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm (Sweden); Dickson, John C. [UCLH NHS Foundation Trust and University College, Institute of Nuclear Medicine, London (United Kingdom); Tossici-Bolt, Livia [University Hospitals Southampton NHS Trust, Department of Medical Physics, Southampton (United Kingdom); Sera, Terez [University of Szeged, Department of Nuclear Medicine and Euromedic Szeged, Szeged (Hungary); Asenbaum, Susanne [Medical University of Vienna, Department of Neurology, Vienna (Austria); Booij, Jan [University of Amsterdam, Department of Nuclear Medicine, Academic Medical Centre, Amsterdam (Netherlands); Kapucu, L. Oezlem A. [Gazi University, Department of Nuclear Medicine, Faculty of Medicine, Ankara (Turkey); Kluge, Andreas [ABX-CRO, Dresden (Germany); Ziebell, Morten [Rigshospitalet and University of Copenhagen, Neurobiology Research Unit, Copenhagen (Denmark); Darcourt, Jacques [University of Nice-Sophia Antipolis, Nuclear Medicine Department, Centre Antoine Lacassagne, Nice (France); Nobili, Flavio [University of Genoa, Clinical Neurology Unit, Department of Neuroscience (DINOGMI), Genoa (Italy); Pagani, Marco [Institute of Cognitive Sciences and Technologies, CNR, Rome (Italy); Karolinska Hospital, Department of Nuclear medicine, Stockholm (Sweden); Sabri, Osama [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Hesse, Swen [University of Leipzig, Department of Nuclear Medicine, Leipzig (Germany); Leipzig University Medical Centre, Molecular Neuroimaging IFB Adiposity Diseases, Leipzig (Germany); Borght, Thierry vander [Universite Catholique de Louvain, Nuclear Medicine Division, Mont-Godinne Medical Center, Yvoir (Belgium); Laere, Koen van [University Hospital and K.U. Leuven, Nuclear Medicine, Leuven (Belgium); Tatsch, Klaus [Staedtisches Klinikum Karlsruhe, Department of Nuclear Medicine, Karlsruhe (Germany); La Fougere, Christian [University of Tuebingen, Division of Nuclear Medicine, Department of Radiology, Tuebingen (Germany)

    2016-07-15

    Even though [{sup 123}I]FP-CIT SPECT provides high accuracy in detecting nigrostriatal cell loss in neurodegenerative parkinsonian syndromes (PS), some patients with an inconclusive diagnosis remain. We investigated whether the diagnostic accuracy in patients with clinically uncertain PS with previously inconclusive findings can be improved by the use of iterative reconstruction algorithms and an improved semiquantitative evaluation which additionally implemented a correction algorithm for patient age and gamma camera dependency (EARL-BRASS; Hermes Medical Solutions, Sweden). We identified 101 patients with inconclusive findings who underwent an [{sup 123}I]FP-CIT SPECT between 2003 and 2010 as part of the diagnostic process of suspected PS at the University of Munich, and re-evaluated these scans using iterative reconstruction algorithms and the new corrected EARL-BRASS. Clinical follow-up was obtained in 62 out of the 101 patients and constituted the gold standard for the re-evaluation to assess the possible improvement in diagnostic accuracy. Clinical follow-up confirmed the diagnosis of PS in 11 of the 62 patients. In patients in whom both visual and semiquantitative analysis showed concordant findings (48 patients), a high negative predictive value (93 %), positive predictive value (100 %) and accuracy (94 %) were found, and thus a correct diagnosis was obtained in 45 of the 48 patients. Among the 14 patients with discordant findings, the additional semiquantitative analysis correctly identified all five of nine patients patients without PS by nonpathological semiquantitative findings in visually pathological or inconclusive scans. In contrast, four of the remaining five patients with decreased semiquantitative values but visually normal scans did not show a PS during follow-up. The age-corrected and camera-corrected mode of evaluation using EARL-BRASS provided a notable improvement in the diagnostic accuracy of [{sup 123}I]FP-CIT SPECT in PS patients with

  10. Exploring the potential of Sentinel-1 data for regional scale slope instability detection using multi-temporal interferometry

    Science.gov (United States)

    Wasowski, Janusz; Bovenga, Fabio; Nutricato, Raffaele; Nitti, Davide Oscar; Chiaradia, Maria Teresa; Refice, Alberto; Pasquariello, Guido

    2016-04-01

    Launched in 2014, the European Space Agency (ESA) Sentinel-1 satellite carrying a medium resolution (20 m) C-Band Synthetic Aperture Radar (SAR) sensor holds much promise for new applications of multi-temporal interferometry (MTI) in landslide assessment. Specifically, the regularity of acquisitions, timeliness of data delivery, shorter repeat cycle (currently 12 days with Sentinel-1A sensor), and flexible incidence angle geometry, all imply better practical utility of MTI relying on Sentinel-1 with respect to MTI based on data from earlier ESA's satellite radar C-band sensors (ERS1/2, ENVISAT). Furthermore, the upcoming launch of Sentinel-1B will cut down the repeat cycle to 6 days, thereby further improving temporal coherence and quality and coverage of MTI products. Taking advantage of the Interferometric Wide (IW) Swath acquisition mode of Sentinel-1 (images covering a 250 km swath on the ground), in this work we test the potential of such data for regional scale slope instability detection through MTI. Our test area includes the landslide-prone Apennine Mountains of Southern Italy. We rely on over 30 Sentinel-1 images, most of which acquired in 2015, and MTI processing through the SPINUA algorithm (Stable Points INterferometry in Un-urbanized Areas). The potential of MTI results based on Sentinel-1 data is assessed by comparing the detected ground surface displacements with the MTI results obtained for the same test area using the C-Band data acquired by ERS1/2 and ENVISAT in 1990s and 2000s. Although the initial results are encouraging, it seems evident that longer-term (few years) acquisitions of Sentinel-1 are necessary to reliably detect some extremely slow movements, which were observed in the last two decades and are likely to be still present in peri-urban areas of many hilltop towns in the Apennine Mts. The MTI results obtained from Sentinel-1 data are also locally compared with the MTI outcomes based on the high resolution (3 m) TerraSAR-X imagery

  11. Contribution of multi-temporal remote sensing images to characterize landslide slip surface ‒ Application to the La Clapière landslide (France

    Directory of Open Access Journals (Sweden)

    B. Casson

    2005-01-01

    Full Text Available Landslide activity is partly controlled by the geometry of the slip surface. This activity is traduced at the surface by displacements and topographic variations. Consequently, multi-temporal remote sensing images can be used in order to characterize the geometry of landslide slip surface and its spatial and temporal evolution. Differential Digital Elevation Models (DEMs are obtained by subtracting two DEMs of different years. A method of multi-temporal images correlation allows to generate displacement maps that can be interpreted in terms of velocity and direction of movements. These data are then used to characterize qualitatively the geometry of the slip surface of the la Clapière landslide (French Southern Alps. Distribution of displacement vectors and of topographic variations are in accordance with a curved slip surface, characterizing a preferential rotational behaviour of this landslide. On the other hand, a spatial and temporal evolution of the geometry of the slip surface is pointed out. Indeed, a propagation of the slip surface under the Iglière bar, in the W part of the landslide, is suspected and can be linked to the acceleration of the landslide in 1987. This study shows the high potential of multi-temporal remote sensing images for slip surface characterization. Although this method could not replace in situ investigations, it can really help to well distribute geophysical profiles or boreholes on unstable areas.

  12. ALOS-PALSAR multi-temporal observation for describing land use and forest cover changes in Malaysia

    Science.gov (United States)

    Avtar, R.; Suzuki, R.; Ishii, R.; Kobayashi, H.; Nagai, S.; Fadaei, H.; Hirata, R.; Suhaili, A. B.

    2012-12-01

    The establishment of plantations in carbon rich peatland of Southeast Asia has shown an increase in the past decade. The need to support development in countries such as Malaysia has been reflected by having a higher rate of conversion of its forested areas to agricultural land use in particular oilpalm plantation. Use of optical data to monitor changes in peatland forests is difficult because of the high cloudiness in tropical region. Synthetic Aperture Radar (SAR) based remote sensing can potentially be used to monitor changes in such forested landscapes. In this study, we have demonstrated the capability of multi-temporal Fine-Beam Dual (FBD) data of Phased Array L-band Synthetic Aperture Radar (PALSAR) to detect forest cover changes in peatland to other landuse such as oilpalm plantation. Here, the backscattering properties of radar were evaluated to estimate changes in the forest cover. Temporal analysis of PALSAR FBD data shows that conversion of peatland forest to oilpalm can be detected by analyzing changes in the value of σoHH and σoHV. This is characterized by a high value of σoHH (-7.89 dB) and σoHV (-12.13 dB) for areas under peat forests. The value of σoHV decreased about 2-4 dB due to the conversion of peatland to a plantation area. There is also an increase in the value of σoHH/σoHV. Changes in σoHV is more prominent to identify the peatland conversion than in the σoHH. The results indicate the potential of PALSAR to estimate peatland forest conversion based on thresholding of σoHV or σoHH/σoHV for monitoring changes in peatland forest. This would improve our understanding of the temporal change and its effect on the peatland forest ecosystem.

  13. Detection of Slope Instabilities Along the National Road 7, Mendoza Province, Argentina, Using Multi-Temporal InSAR

    Science.gov (United States)

    Michoud, Clément; Derron, Marc-Henri; Baumann, Valérie; Jaboyedoff, Michel; Rune Lauknes, Tom

    2013-04-01

    About 2'230 vehicles per day pass through the National Road 7 that link Buenos Aires to Santiago de Chile, crossing Andes Cordillera. This extremely important corridor, being the most important land pass between Argentina and Chile, is exposed to numerous natural hazards, such as snow avalanches, rockfalls and debris flows and remains closed by natural hazards several days per year. This goal of this study is to perform a regional mapping of geohazard susceptibilities along the Road 7 corridor, as started by Baumann et al. (2005), using modern remote sensing and numerical approaches with field checking. The area of interest is located in the Mendoza Province, between the villages Potrerillos and Las Cuevas near the Chilean border. The diversity of soil and rock conditions, the active geomorphological processes associated to post-glacial decompression, seasonal freeze and thaw and severe storms along the road corridor, increase the risk to natural hazard. With the support of the European Space Agency (ESA Category-1 Project 7154), we have in this study processed a large number of ERS and Envisat ASAR scenes, covering the period from 1995 to 2000. We applied both the small-baseline (SB) and the persistent scatterer (PSI) multi-temporal interferometric SAR (InSAR) techniques. The study area contains sparse vegetation, and the SB InSAR method is therefore well suited to map the area containing mainly distributed scatterers. Furthermore, PSI algorithms are also used for comparison for selected landslides in the inventory. Both approaches show a relatively good coherence within mountain areas, which is a good point for the landslide detections along the road. Indeed, the authors identified several large slope instabilities even active scree deposits. This inventory is finally compared with field observations and with existing susceptibility maps regarding snow avalanches, debris-flows and rockfalls. The final objective of this project is to develop a risk strategy that

  14. Quantifying soil carbon loss and uncertainty from a peatland wildfire using multi-temporal LiDAR

    Science.gov (United States)

    Reddy, Ashwan D.; Hawbaker, Todd J.; Wurster, F.; Zhu, Zhiliang; Ward, S.; Newcomb, Doug; Murray, R.

    2015-01-01

    Peatlands are a major reservoir of global soil carbon, yet account for just 3% of global land cover. Human impacts like draining can hinder the ability of peatlands to sequester carbon and expose their soils to fire under dry conditions. Estimating soil carbon loss from peat fires can be challenging due to uncertainty about pre-fire surface elevations. This study uses multi-temporal LiDAR to obtain pre- and post-fire elevations and estimate soil carbon loss caused by the 2011 Lateral West fire in the Great Dismal Swamp National Wildlife Refuge, VA, USA. We also determine how LiDAR elevation error affects uncertainty in our carbon loss estimate by randomly perturbing the LiDAR point elevations and recalculating elevation change and carbon loss, iterating this process 1000 times. We calculated a total loss using LiDAR of 1.10 Tg C across the 25 km2 burned area. The fire burned an average of 47 cm deep, equivalent to 44 kg C/m2, a value larger than the 1997 Indonesian peat fires (29 kg C/m2). Carbon loss via the First-Order Fire Effects Model (FOFEM) was estimated to be 0.06 Tg C. Propagating the LiDAR elevation error to the carbon loss estimates, we calculated a standard deviation of 0.00009 Tg C, equivalent to 0.008% of total carbon loss. We conclude that LiDAR elevation error is not a significant contributor to uncertainty in soil carbon loss under severe fire conditions with substantial peat consumption. However, uncertainties may be more substantial when soil elevation loss is of a similar or smaller magnitude than the reported LiDAR error.

  15. Assessment of Water Availability Impact on Wetland Management using Multi-temporal Landsat Images and Bayesian-based Learning Machines

    Science.gov (United States)

    Alminagorta, O.; Torres, A. F.

    2013-12-01

    Water availability has a direct impact on the wetland ecosystems. While wetland managers need better information to allocate scarce water to improve wetland services, most monitoring activities of flood areas and vegetation condition on wetlands relies on manual estimation of water depth and use of airboat with GPS devices. This process is costly and time-consuming. Remote sensing techniques have been previously used to characterize vegetation conditions along with hydrological characteristics of the wetlands with excellent results. Nevertheless, limited analysis has been done to relate the resulting wetland characterization with the historical water availability records. The present paper addresses the lack of adequate feedback on wetland conditions upon the available water for the wetland system by making use of multi-temporal Landsat images. These images are processed at wetland unit and system level to extract information about vegetation, soil and water conditions. This information is then correlated with historical water availability records for the wetland system by means of the Relevance Vector Machine, a Bayesian-based algorithm known for its robustness, efficiency, and sparseness. This research is applied at the Bear River Migratory Bird Refuge (the Refuge), located on the northeast side of Great Salt Lake, Utah. The Refuge constitutes one of the most important habitats for migratory birds for the Pacific Flyway of North America. Water-discharge records and coverage vegetation collected at the Refuge has been used to calibrate and evaluate the effects on wetland services to the process of flooding and drought in wetland units during different years. The final product of this research is to provide a methodology that wetland managers can use to make informed decisions about water allocation to improve wetland services while avoiding wasting resources, effort, time and money.

  16. The multi temporal/multi-model approach to predictive uncertainty assessment in real-time flood forecasting

    Science.gov (United States)

    Barbetta, Silvia; Coccia, Gabriele; Moramarco, Tommaso; Brocca, Luca; Todini, Ezio

    2017-08-01

    This work extends the multi-temporal approach of the Model Conditional Processor (MCP-MT) to the multi-model case and to the four Truncated Normal Distributions (TNDs) approach, demonstrating the improvement on the single-temporal one. The study is framed in the context of probabilistic Bayesian decision-making that is appropriate to take rational decisions on uncertain future outcomes. As opposed to the direct use of deterministic forecasts, the probabilistic forecast identifies a predictive probability density function that represents a fundamental knowledge on future occurrences. The added value of MCP-MT is the identification of the probability that a critical situation will happen within the forecast lead-time and when, more likely, it will occur. MCP-MT is thoroughly tested for both single-model and multi-model configurations at a gauged site on the Tiber River, central Italy. The stages forecasted by two operative deterministic models, STAFOM-RCM and MISDc, are considered for the study. The dataset used for the analysis consists of hourly data from 34 flood events selected on a time series of six years. MCP-MT improves over the original models' forecasts: the peak overestimation and the rising limb delayed forecast, characterizing MISDc and STAFOM-RCM respectively, are significantly mitigated, with a reduced mean error on peak stage from 45 to 5 cm and an increased coefficient of persistence from 0.53 up to 0.75. The results show that MCP-MT outperforms the single-temporal approach and is potentially useful for supporting decision-making because the exceedance probability of hydrometric thresholds within a forecast horizon and the most probable flooding time can be estimated.

  17. Multi-temporal Soil Erosion Modelling over the Mt Kenya Region with Multi-Sensor Earth Observation Data

    Science.gov (United States)

    Symeonakis, Elias; Higginbottom, Thomas

    2015-04-01

    Accelerated soil erosion is the principal cause of soil degradation across the world. In Africa, it is seen as a serious problem creating negative impacts on agricultural production, infrastructure and water quality. Regarding the Mt Kenya region, specifically, soil erosion is a serious threat mainly due to unplanned and unsustainable practices linked to tourism, agriculture and rapid population growth. The soil types roughly correspond with different altitudinal zones and are generally very fertile due to their volcanic origin. Some of them have been created by eroding glaciers while others are due to millions of years of fluvial erosion. The soils on the mountain are easily eroded once exposed: when vegetation is removed, the soil quickly erodes down to bedrock by either animals or humans, as tourists erode paths and local people clear large swaths of forested land for agriculture, mostly illegally. It is imperative, therefore, that a soil erosion monitoring system for the Mt Kenya region is in place in order to understand the magnitude of, and be able to respond to, the increasing number of demands on this renewable resource. In this paper, we employ a simple regional-scale soil erosion modelling framework based on the Thornes model and suggest an operational methodology for quantifying and monitoring water runoff and soil erosion using multi-sensor and multi-temporal remote sensing data in a GIS framework. We compare the estimates of this study with general data on the severity of soil erosion over Kenya and with measured rates of soil loss at different locations over the area of study. The results show that the measured and estimated rates of erosion are generally similar and within the same order of magnitude. They also show that, over the last years, erosion rates are increasing in large parts of the region at an alarming rate, and that mitigation measures are needed to reverse the negative effects of uncontrolled socio-economic practices.

  18. Inter-annual surface evolution of an Antarctic blue-ice moraine using multi-temporal DEMs

    Science.gov (United States)

    Westoby, M. J.; Dunning, S. A.; Woodward, J.; Hein, A. S.; Marrero, S. M.; Winter, K.; Sugden, D. E.

    2015-11-01

    Multi-temporal and fine resolution topographic data products are being increasingly used to quantify surface elevation change in glacial environments. In this study, we employ 3-D digital elevation model (DEM) differencing to quantify the topographic evolution of a blue-ice moraine complex in front of Patriot Hills, Heritage Range, Antarctica. Terrestrial laser scanning (TLS) was used to acquire multiple topographic datasets of the moraine surface at the beginning and end of the austral summer season in 2012/2013 and during a resurvey field campaign in 2014. A complementary topographic dataset was acquired at the end of season 1 through the application of Structure-from-Motion (SfM) photogrammetry to a set of aerial photographs taken from an unmanned aerial vehicle (UAV). Three-dimensional cloud-to-cloud differencing was undertaken using the Multiscale Model to Model Cloud Comparison (M3C2) algorithm. DEM differencing revealed net uplift and lateral movement of the moraine crests within season 1 (mean uplift ∼ 0.10 m), with lowering of a similar magnitude in some inter-moraine depressions and close to the current ice margin. Our results indicate net uplift across the site between seasons 1 and 2 (mean 0.07 m). This research demonstrates that it is possible to detect dynamic surface topographical change across glacial moraines over short (annual to intra-annual) timescales through the acquisition and differencing of fine-resolution topographic datasets. Such data offer new opportunities to understand the process linkages between surface ablation, ice flow, and debris supply within moraine ice.

  19. Vegetation cover change detection and assessment in arid environment using multi-temporal remote sensing images and ecosystem management approach

    Science.gov (United States)

    Abdelrahman Aly, Anwar; Mosa Al-Omran, Abdulrasoul; Shahwan Sallam, Abdulazeam; Al-Wabel, Mohammad Ibrahim; Shayaa Al-Shayaa, Mohammad

    2016-04-01

    Vegetation cover (VC) change detection is essential for a better understanding of the interactions and interrelationships between humans and their ecosystem. Remote sensing (RS) technology is one of the most beneficial tools to study spatial and temporal changes of VC. A case study has been conducted in the agro-ecosystem (AE) of Al-Kharj, in the center of Saudi Arabia. Characteristics and dynamics of total VC changes during a period of 26 years (1987-2013) were investigated. A multi-temporal set of images was processed using Landsat images from Landsat4 TM 1987, Landsat7 ETM+2000, and Landsat8 to investigate the drivers responsible for the total VC pattern and changes, which are linked to both natural and social processes. The analyses of the three satellite images concluded that the surface area of the total VC increased by 107.4 % between 1987 and 2000 and decreased by 27.5 % between years 2000 and 2013. The field study, review of secondary data, and community problem diagnosis using the participatory rural appraisal (PRA) method suggested that the drivers for this change are the deterioration and salinization of both soil and water resources. Ground truth data indicated that the deteriorated soils in the eastern part of the Al-Kharj AE are frequently subjected to sand dune encroachment, while the southwestern part is frequently subjected to soil and groundwater salinization. The groundwater in the western part of the ecosystem is highly saline, with a salinity ≥ 6 dS m-1. The ecosystem management approach applied in this study can be used to alike AE worldwide.

  20. Multi-sensor and multi-temporal data fusion for measurement of depositional features at Augustine Volcano, south-central Alaska

    Science.gov (United States)

    McAlpin, D. B.; Meyer, F. J.

    2012-12-01

    In this paper, optical, SAR, and InSAR data from the 2006 eruption of Augustine Volcano, are used to demonstrate how fusion of photogrammatically derived, high resolution DEMs can be used to quantify extent and volume of eruption-related depositional features; to improve the sensitivity and accuracy of differential InSAR (d-InSAR) for volcano deformation monitoring; and how coherence maps of lava, pyroclastic flow deposits, and lahars provide information on deposition history and coherence recovery time of areas disrupted by lahars. Augustine Volcano's most recent eruption occurred in December 2005 through March 2006. Post 2006-eruption data from the ALOS-PRISM satellite is available from image acquisitions on 21 September 2007, 25 May 2008, and 26 September 2009. The ALOS-PRISM instrument consists of three independent panchromatic radiometers for simultaneous imaging in nadir, forward, and backward directions. This results in along-track stereoscopy in overlapping images (triplets), with horizontal resolution at nadir of 2.5-meters. DEMs produced from these high resolution triplets are compared to pre-eruption DEMs from the Shuttle Radar Topography Mission (SRTM) to delineate depositional features and quantify their volumes. Multi-temporal DEMs are also beneficial for the generation of topography-free d-InSAR images Separate d-InSAR analyses based on DEMs from PRISM triplets and the SRTM demonstrate the improvement in deformation-estimate precision that is achieved by using high-resolution DEM information. Augustine's 2006 eruption produced significant lava flows, pyroclastic flows, and lahars, which were previously mapped in detail. Coherence mapping from pre- and post-eruption Envisat data are validated by comparison to the available detail maps, and analyzed to determine the extent to which coherence mapping can resolve the time sequence of deposition during the 2006 eruption. Additional radar data sets are available from the Phased Array type L-band Synthetic

  1. Model-based surface soil moisture (SSM) retrieval algorithm using multi-temporal RISAT-1 C-band SAR data

    Science.gov (United States)

    Pandey, Dharmendra K.; Maity, Saroj; Bhattacharya, Bimal; Misra, Arundhati

    2016-05-01

    Accurate measurement of surface soil moisture of bare and vegetation covered soil over agricultural field and monitoring the changes in surface soil moisture is vital for estimation for managing and mitigating risk to agricultural crop, which requires information and knowledge to assess risk potential and implement risk reduction strategies and deliver essential responses. The empirical and semi-empirical model-based soil moisture inversion approach developed in the past are either sensor or region specific, vegetation type specific or have limited validity range, and have limited scope to explain physical scattering processes. Hence, there is need for more robust, physical polarimetric radar backscatter model-based retrieval methods, which are sensor and location independent and have wide range of validity over soil properties. In the present study, Integral Equation Model (IEM) and Vector Radiative Transfer (VRT) model were used to simulate averaged backscatter coefficients in various soil moisture (dry, moist and wet soil), soil roughness (smooth to very rough) and crop conditions (low to high vegetation water contents) over selected regions of Gujarat state of India and the results were compared with multi-temporal Radar Imaging Satellite-1 (RISAT-1) C-band Synthetic Aperture Radar (SAR) data in σ°HH and σ°HV polarizations, in sync with on field measured soil and crop conditions. High correlations were observed between RISAT-1 HH and HV with model simulated σ°HH & σ°HV based on field measured soil with the coefficient of determination R2 varying from 0.84 to 0.77 and RMSE varying from 0.94 dB to 2.1 dB for bare soil. Whereas in case of winter wheat crop, coefficient of determination R2 varying from 0.84 to 0.79 and RMSE varying from 0.87 dB to 1.34 dB, corresponding to with vegetation water content values up to 3.4 kg/m2. Artificial Neural Network (ANN) methods were adopted for model-based soil moisture inversion. The training datasets for the NNs were

  2. Response of a boreal forest to canopy opening: assessing vertical and lateral tree growth with multi-temporal lidar data.

    Science.gov (United States)

    Vepakomma, Udayalakshmi; St-Onge, Benoit; Kneeshaw, Daniel

    2011-01-01

    Fine-scale height-growth response of boreal trees to canopy openings is difficult to measure from the ground, and there are important limitations in using stereophotogrammetry in defining gaps and determining individual crowns and height. However, precise knowledge on height growth response to different openings is critical for refining partial harvesting techniques. In this study, we question whether conifers and hardwoods respond equally in terms of sapling growth or lateral growth to openings. We also ask to what distance gaps affect tree growth into the forest. We use multi-temporal lidar to characterize tree/sapling height and lateral growth responses over five years to canopy openings and high resolution images to identify conifers and hardwoods. Species-class-wise height-growth patterns of trees/saplings in various neighborhood contexts were determined across a 6-km matrix of Canadian boreal mixed deciduous coniferous forests. We then use statistical techniques to probe how these growth responses vary by spatial location with respect to the gap edge. Results confirm that both mechanisms of gap closure contribute to the closing of canopies at a rate of 1.2% per annum. Evidence also shows that both hardwood and conifer gap edge trees have a similar lateral growth (average of 22 cm/yr) and similar rates of height growth irrespective of their location and initial height. Height growth of all saplings, however, was strongly dependent on their position within the gap and the size of the gap. Results suggest that hardwood and softwood saplings in gaps have greatest growth rates at distances of 0.5-2 m and 1.5-4 m from the gap edge and in openings smaller than 800 m2 and 250 m2, respectively. Gap effects on the height growth of trees in the intact forest were evident up to 30 m and 20 m from gap edges for hardwood and softwood overstory trees, respectively. Our results thus suggest that foresters should consider silvicultural techniques that create many small

  3. Using high resolution satellite multi-temporal interferometry for landslide hazard detection in tropical environments: the case of Haiti

    Science.gov (United States)

    Wasowski, Janusz; Nutricato, Raffaele; Nitti, Davide Oscar; Bovenga, Fabio; Chiaradia, Maria Teresa; Piard, Boby Emmanuel; Mondesir, Philemon

    2015-04-01

    Synthetic aperture radar (SAR) multi-temporal interferometry (MTI) is one of the most promising satellite-based remote sensing techniques for fostering new opportunities in landslide hazard detection and assessment. MTI is attractive because it can provide very precise quantitative information on slow slope displacements of the ground surface over huge areas with limited vegetation cover. Although MTI is a mature technique, we are only beginning to realize the benefits of the high-resolution imagery that is currently acquired by the new generation radar satellites (e.g., COSMO-SkyMed, TerraSAR-X). In this work we demonstrate the potential of high resolution X-band MTI for wide-area detection of slope instability hazards even in tropical environments that are typically very harsh (eg. coherence loss) for differential interferometry applications. This is done by presenting an example from the island of Haiti, a tropical region characterized by dense and rapidly growing vegetation, as well as by significant climatic variability (two rainy seasons) with intense precipitation events. Despite the unfavorable setting, MTI processing of nearly 100 COSMO-SkyMed (CSK) mages (2011-2013) resulted in the identification of numerous radar targets even in some rural (inhabited) areas thanks to the high resolution (3 m) of CSK radar imagery, the adoption of a patch wise processing SPINUA approach and the presence of many man-made structures dispersed in heavily vegetated terrain. In particular, the density of the targets resulted suitable for the detection of some deep-seated and shallower landslides, as well as localized, very slow slope deformations. The interpretation and widespread exploitation of high resolution MTI data was facilitated by Google EarthTM tools with the associated high resolution optical imagery. Furthermore, our reconnaissance in situ checks confirmed that MTI results provided useful information on landslides and marginally stable slopes that can represent a

  4. Multi-temporal thermal analyses for submarine groundwater discharge (SGD) detection over large spatial scales in the Mediterranean

    Science.gov (United States)

    Hennig, Hanna; Mallast, Ulf; Merz, Ralf

    2015-04-01

    steep than the slope of the surrounding area, resulting in less influence through outliers and an equal weighting of all integrated scenes. Both methods could be used to detect SGD sites in the Mediterranean regardless to the discharge characteristics (diffuse and focused) exceptions are sites with deep emergences. Better results could be shown in bays compared to more exposed sites. Since the range of the SST is mostly influenced by maximum and minimum of the scenes, the slope approach can be seen as a more representative method using all scenes. References: Mallast, U., Gloaguen, R., Friesen, J., Rödiger, T., Geyer, S., Merz, R., Siebert, C., 2014. How to identify groundwater-caused thermal anomalies in lakes based on multi-temporal satellite data in semi-arid regions. Hydrol. Earth Syst. Sci. 18 (7), 2773-2787.

  5. Multi-temporal UAV-borne LiDAR point clouds for vegetation analysis - a case study

    Science.gov (United States)

    Mandlburger, Gottfried; Wieser, Martin; Hollaus, Markus; Pfennigbauer, Martin; Riegl, Ursula

    2016-04-01

    decrease of ca. 50% is compensated by an increase in the upper canopy area (>20 m a.g.l.; Feb: 348 points/m2, Oct: 757 points/m2, increase rate: 118%). The greater leaf area in October results in more laser echoes from the canopy but the density decrease on the ground is not entirely attributed to shadowing from the upper canopy as the point distribution is nearly constant in the medium (10-20 m) and lower (0-10 m) sub-canopy area. The lower density on the ground is rather caused by a densely foliated shrub layer (0.15-3 m; Feb: 178 points/m2, Oct: 259 points/m2, increase rate: 46%). A sharp ground point density drop could be observed in areas covered by an invasive weed species (Fallopia japonica) which keeps its extremely dense foliage till late in the year. In summary, the preliminary point density study has shown the potential of UAV-borne, multi-temporal LiDAR for characterization of seasonal vegetation changes in deciduous environments. It is remarkable that even under leaf-on conditions a very high terrain point density is achievable. Except for the dense shrub layer, the case study has shown a similar 3D point distribution in the sub-canopy area for leaf-off and leaf-on data acquisition.

  6. Evaluation of DSMs generated from multi-temporal aerial photographs using emerging structure from motion-multi-view stereo technology

    Science.gov (United States)

    Ishiguro, Satoshi; Yamano, Hiroya; Oguma, Hiroyuki

    2016-09-01

    An accuracy assessment of digital surface models (DSMs) generated from archived aerial photographs using the structure from motion-multi-view stereo (SfM-MVS) technique was carried out. A four-step accuracy-assessment procedure was adopted using aerial photography from eight periods, as follows. Step 1: generate a DSM and orthophoto from digital aerial photographs taken in 2013 and ground control points (GCPs) measured by GNSS. Step 2: assess the accuracy of the DSM by comparison with altitude measured by leveling survey. Step 3: generate other historical DSMs and orthophotos from historical aerial photographs using GCPs extracted from the DSM of 2013. Step 4: assess the accuracy of all historical DSMs by comparing with the leveling survey. Then re-calculate the accuracy of historical DSMs by reducing the inherent error in the 2013 DSM. The DSM based on the aerial photographs taken in 2013 was generated with a resolution of 48.2 cm. The residual height error of the GCPs was 15.4 cm. Validation against the altitudes of 171 points revealed that this DSM has a height root-mean-square-error (RMSE) of 24.1 cm and is 9.2 cm lower than the leveling data on average. Even using US military photos with unconfirmed detailed specifications, the model can measure the altitude with an RMSE value of 121.5 cm. It appears therefore that analysis by SfM-MVS can give comparable measurement accuracy to traditional aerial photogrammetry. The low cost and high accuracy obtained with archived aerial photographs are worthy of special mention.

  7. Modelling of oil spill frequency, leak sources and contamination probability in the Caspian Sea using multi-temporal SAR images 2006–2010 and stochastic modelling

    Directory of Open Access Journals (Sweden)

    Emil Bayramov

    2016-05-01

    Full Text Available The main goal of this research was to detect oil spills, to determine the oil spill frequencies and to approximate oil leak sources around the Oil Rocks Settlement, the Chilov and Pirallahi Islands in the Caspian Sea using 136 multi-temporal ENVISAT Advanced Synthetic Aperture Radar Wide Swath Medium Resolution images acquired during 2006–2010. The following oil spill frequencies were observed around the Oil Rocks Settlement, the Chilov and Pirallahi Islands: 2–10 (3471.04 sq km, 11–20 (971.66 sq km, 21–50 (692.44 sq km, 51–128 (191.38 sq km. The most critical oil leak sources with the frequency range of 41–128 were observed at the Oil Rocks Settlement. The exponential regression analysis between wind speeds and oil slick areas detected from 136 multi-temporal ENVISAT images revealed the regression coefficient equal to 63%. The regression model showed that larger oil spill areas were observed with decreasing wind speeds. The spatiotemporal patterns of currents in the Caspian Sea explained the multi-directional spatial distribution of oil spills around Oil Rocks Settlement, the Chilov and Pirallahi Islands. The linear regression analysis between detected oil spill frequencies and predicted oil contamination probability by the stochastic model showed the positive trend with the regression coefficient of 30%.

  8. Large-Area Landslides Monitoring Using Advanced Multi-Temporal InSAR Technique over the Giant Panda Habitat, Sichuan, China

    Directory of Open Access Journals (Sweden)

    Panpan Tang

    2015-07-01

    Full Text Available The region near Dujiangyan City and Wenchuan County, Sichuan China, including significant giant panda habitats, was severely impacted by the Wenchuan earthquake. Large-area landslides occurred and seriously threatened the lives of people and giant pandas. In this paper, we report the development of an enhanced multi-temporal interferometric synthetic aperture radar (MTInSAR methodology to monitor potential post-seismic landslides by analyzing coherent scatterers (CS and distributed scatterers (DS points extracted from multi-temporal l-band ALOS/PALSAR data in an integrated manner. Through the integration of phase optimization and mitigation of the orbit and topography-related phase errors, surface deformations in the study area were derived: the rates in the line of sight (LOS direction ranged from −7 to 1.5 cm/a. Dozens of potential landslides, distributed mainly along the Minjiang River, Longmenshan Fault, and in other the high-altitude areas were detected. These findings matched the distribution of previous landslides. InSAR-derived results demonstrated that some previous landslides were still active; many unstable slopes have developed, and there are significant probabilities of future massive failures. The impact of landslides on the giant panda habitat, however ranged from low to moderate, would continue to be a concern for conservationists for some time in the future.

  9. Assessment of degradation in coral reef communities using multi-temporal QuickBird imagery in Kish Island, the Persian Gulf

    Science.gov (United States)

    Kabiri, Keivan

    Differential image processing analysis were utilized to detect changes occurred in the significant coral reef communities located around the Kish Island in the northern side of the Persian Gulf. In this regard, multi-temporal bands of two QuickBird images (for years 2005 and 2008) were applied to implement change detection analysis. The methodology conducted in this research was based on integration of class-wised and pixel-wised change detection methodologies to highlight the variations in situation of corals. Moreover, some historical field observations from the study area were employed to fulfill required image classifications, as well as for assessment and validation of the obtained results. The results demonstrated that most of coral reefs of the study area were under stress between 2005 and 2008. Furthermore, field observations proved that most of these stresses come from the bleaching happened in August 2007, which caused a massive degradation and mass moralities in coral reef communities. Finally, it is resulted that multi-temporal/multi-spectral high resolution satellite imagery is beneficial to utilize for investigation of degradation in the coral reefs, particularly for inaccessible islands and in absence of field observations.

  10. Evaluation of registration accuracy between Sentinel-2 and Landsat 8

    Science.gov (United States)

    Barazzetti, Luigi; Cuca, Branka; Previtali, Mattia

    2016-08-01

    Starting from June 2015, Sentinel-2A is delivering high resolution optical images (ground resolution up to 10 meters) to provide a global coverage of the Earth's land surface every 10 days. The planned launch of Sentinel-2B along with the integration of Landsat images will provide time series with an unprecedented revisit time indispensable for numerous monitoring applications, in which high resolution multi-temporal information is required. They include agriculture, water bodies, natural hazards to name a few. However, the combined use of multi-temporal images requires an accurate geometric registration, i.e. pixel-to-pixel correspondence for terrain-corrected products. This paper presents an analysis of spatial co-registration accuracy for several datasets of Sentinel-2 and Landsat 8 images distributed all around the world. Images were compared with digital correlation techniques for image matching, obtaining an evaluation of registration accuracy with an affine transformation as geometrical model. Results demonstrate that sub-pixel accuracy was achieved between 10 m resolution Sentinel-2 bands (band 3) and 15 m resolution panchromatic Landsat images (band 8).

  11. Rice Fields Mapping in Fragmented Area Using Multi-Temporal HJ-1A/B CCD Images

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2015-03-01

    Full Text Available Rice is one of the most important crops in the world; meanwhile, the rice field is also an important contributor to greenhouse gas methane emission. Therefore, it is important to get an accurate estimation of rice acreage for both food production and climate change related studies. The eastern plain region is one of the major single-cropped rice (SCR growing areas in China. Subjected to the topography and intensified human activities, the rice fields are generally fragmented and irregular. How remote sensing can meet this challenge to accurately estimate the acreage of the rice in this region using medium-resolution imagery is the topic of this study. In this study, the applicability of the Chinese HJ-1A/B satellites and a two-band enhanced vegetation index (EVI2 was investigated. Field campaigns were carried out during the rice growing season and ground-truth data were collected for classification accuracy assessments in 2012. A stepwise classification strategy utilizing the EVI2 signatures during key phenology stages, i.e., the transplanting and the vegetative to reproductive transition phases, of the SCR was proposed, and the overall classification accuracy was 91.7%. The influence of the mixed pixel and boundary effects to classification accuracy was also investigated. This work demonstrates that the Chinese HJ-1A/B data are suitable data source to estimating SCR cropping area under complex land cover composition.

  12. Automatic analysis of change detection of multi-temporal ERS-2 SAR images by using two-threshold EM and MRF algorithms

    Institute of Scientific and Technical Information of China (English)

    CHEN Fei; LUO Lin; JIN Yaqiu

    2004-01-01

    To automatically detect and analyze the surface change in the urban area from multi-temporal SAR images, an algorithm of two-threshold expectation maximum (EM) and Markov random field (MRF) is developed. Difference of the SAR images demonstrates variation of backscattering caused by the surface change all over the image pixels. Two thresholds are obtained by the EM iterative process and categorized to three classes: enhanced scattering, reduced scattering and unchanged regimes. Initializing from the EM result, the iterated conditional modes (ICM) algorithm of the MRF is then used to analyze the detection of contexture change in the urban area. As an example, two images of the ERS-2 SAR in 1996 and 2002 over the Shanghai City are studied.

  13. Vegetation cover dynamics of the Mongolian semiarid zone according to multi-temporal LANDSAT imagery (the case of Darkhan test range)

    Science.gov (United States)

    Zharnikova, M. A.; Alymbaeva, ZH B.; Ayurzhanaev, A. A.; Garmaev, E. ZH

    2016-11-01

    At present much attention is given to the spatio-temporal dynamics of plant communities of steppes to assess their response to the current climate changes. In this study, a mapping of a selected modeling polygon was carried out on the basis of data decoding and field surveys of vegetation cover in the semi-arid zone. The resulting large-scale map of actual vegetation reflects the current state of the vegetation cover and its horizontal structure. It is a valuable material for monitoring of changes in the chosen area. With multi-temporal satellite Landsat imagery we consider the vegetation cover dynamics of the test range. To analyze the transformation of the environment by the climatic factors, we compared series of NDVI versus the precipitation and of NDVI versus the temperatures. Then we calculated the degree of correlation between them.

  14. A particle swarm optimized kernel-based clustering method for crop mapping from multi-temporal polarimetric L-band SAR observations

    Science.gov (United States)

    Tamiminia, Haifa; Homayouni, Saeid; McNairn, Heather; Safari, Abdoreza

    2017-06-01

    Polarimetric Synthetic Aperture Radar (PolSAR) data, thanks to their specific characteristics such as high resolution, weather and daylight independence, have become a valuable source of information for environment monitoring and management. The discrimination capability of observations acquired by these sensors can be used for land cover classification and mapping. The aim of this paper is to propose an optimized kernel-based C-means clustering algorithm for agriculture crop mapping from multi-temporal PolSAR data. Firstly, several polarimetric features are extracted from preprocessed data. These features are linear polarization intensities, and several statistical and physical based decompositions such as Cloude-Pottier, Freeman-Durden and Yamaguchi techniques. Then, the kernelized version of hard and fuzzy C-means clustering algorithms are applied to these polarimetric features in order to identify crop types. The kernel function, unlike the conventional partitioning clustering algorithms, simplifies the non-spherical and non-linearly patterns of data structure, to be clustered easily. In addition, in order to enhance the results, Particle Swarm Optimization (PSO) algorithm is used to tune the kernel parameters, cluster centers and to optimize features selection. The efficiency of this method was evaluated by using multi-temporal UAVSAR L-band images acquired over an agricultural area near Winnipeg, Manitoba, Canada, during June and July in 2012. The results demonstrate more accurate crop maps using the proposed method when compared to the classical approaches, (e.g. 12% improvement in general). In addition, when the optimization technique is used, greater improvement is observed in crop classification, e.g. 5% in overall. Furthermore, a strong relationship between Freeman-Durden volume scattering component, which is related to canopy structure, and phenological growth stages is observed.

  15. A novel flood detection mapping using multi-temporal RADARSAT-2 and TerraSAR-X images through an optimized Taguchi based classification technique

    Science.gov (United States)

    Pradhan, Biswajeet

    2016-07-01

    Floods are considered as one of the most common natural disasters in Malaysia. Preparation of an actuate flood inventory map is the basic step in flood risk management. Flood detection is yet significantly complex process due to the presence of cloud coverage in the tropical areas especially in Malaysia. Moreover, the most available techniques are expensive and time-consuming. Therefore, in the present study an efficient approach is presented to identify the flooded areas by means of multi-temporal RADARSAT-2 and single Terra-SAR-X images. The proposed framework was tested at two tropical areas in Malaysia: Kelantan (2014 flood); and Kuala Terengganu (2009 flood) to map the flooded areas. Multi-temporal RADARSAT-2 and single TerrSAR-X and Landsat images were classified based on a rule-based object-oriented technique. Then, different levels of image segmentation was performed to distinguish the boundaries of various dimensions and scales of objects. Finally, a novel Taguchi based method was employed to optimize the segmentation parameters. After the completion of segmentation, the rules were defined and the images were classified to produce an accurate flood inventory map for both 2014 Kelantan flood event as well as 2009 flood event in Kuala Terengganu. Finally, the results of classification were measured through the confusion matrix. In this research, the combination of techniques and the optimization approach were applied as a pioneering approach for flood detection. The flood inventory map which was obtained by using the proposed approach is showing the efficiency of the methodology which can be applied by other researchers and decision makers to construct the flood inventory maps. Keywords: Radarsat 2; Multispectral imagery; flood detection; Taguchi; rule-based classification

  16. Multi-temporal and multi-platforms remote sensing data for the analysis of open-pit mining earth surface dynamics

    Science.gov (United States)

    Feng, Zengwen; Chen, Jianping; Li, Ke; Tarolli, Paolo

    2015-04-01

    Open-pit mining activities can affect the earth surface processes inducing soil erosion, landslides, and subsidence. The recognition and the analysis of mining induced Earth surface changes and the related processes represent, therefore, a challenge for a sustainable environmental planning for those regions affected by an intense mining activity. The purpose of this study is to monitor the effects of open-pit mining and the associated landform processes using multi-temporal and multi-platforms remote sensing data. The study area consists in an open-pit mine located in Miyun county, northern Beijing. For the study area different datasets are available for different years: a GeoEye image (2011, res. 1m/pix), two pairs of Cartosat - 1 stereo pairs (2009, 2012, res. 2.5m/pix) from which we extracted two DSMs (res. 5m/pix), an UAV aerial photograph (2014, res. 0.07m) and the derived DSM (2014, res. 0.1m). We also obtained a DTM (2014, res. 1m) from terrestrial laser scanner (TLS) and a DSM (2014, res. 0.5m) using the Structure from Motion (SfM) technique by a camera. These data served as the basis to recognize, through the application of morphometric indicators, the areas subject to erosion and landsliding. A volumetric estimate of soil loss from 2009 to 2014 has been also quantified using the multiple DSMs provided by the multi-platform. The recognition and the analysis of earth surface dynamics using low-cost multi-temporal and multi-platforms remote sensing such as SfM and UAVs represents a useful tool to mitigate the environmental consequences open-pit mining, and to mitigate the related natural disaster and risk.

  17. The Relational Database Dictionary

    CERN Document Server

    J, C

    2006-01-01

    Avoid misunderstandings that can affect the design, programming, and use of database systems. Whether you're using Oracle, DB2, SQL Server, MySQL, or PostgreSQL, The Relational Database Dictionary will prevent confusion about the precise meaning of database-related terms (e.g., attribute, 3NF, one-to-many correspondence, predicate, repeating group, join dependency), helping to ensure the success of your database projects. Carefully reviewed for clarity, accuracy, and completeness, this authoritative and comprehensive quick-reference contains more than 600 terms, many with examples, covering i

  18. Multi-Temporal Independent Component Analysis and Landsat 8 for Delineating Maximum Extent of the 2013 Colorado Front Range Flood

    Directory of Open Access Journals (Sweden)

    Stephen M. Chignell

    2015-07-01

    Full Text Available Maximum flood extent—a key data need for disaster response and mitigation—is rarely quantified due to storm-related cloud cover and the low temporal resolution of optical sensors. While change detection approaches can circumvent these issues through the identification of inundated land and soil from post-flood imagery, their accuracy can suffer in the narrow and complex channels of increasingly developed and heterogeneous floodplains. This study explored the utility of the Operational Land Imager (OLI and Independent Component Analysis (ICA for addressing these challenges in the unprecedented 2013 Flood along the Colorado Front Range, USA. Pre- and post-flood images were composited and transformed with an ICA to identify change classes. Flooded pixels were extracted using image segmentation, and the resulting flood layer was refined with cloud and irrigated agricultural masks derived from the ICA. Visual assessment against aerial orthophotography showed close agreement with high water marks and scoured riverbanks, and a pixel-to-pixel validation with WorldView-2 imagery captured near peak flow yielded an overall accuracy of 87% and Kappa of 0.73. Additional tests showed a twofold increase in flood class accuracy over the commonly used modified normalized water index. The approach was able to simultaneously distinguish flood-related water and soil moisture from pre-existing water bodies and other spectrally similar classes within the narrow and braided channels of the study site. This was accomplished without the use of post-processing smoothing operations, enabling the important preservation of nuanced inundation patterns. Although flooding beneath moderate and sparse riparian vegetation canopy was captured, dense vegetation cover and paved regions of the floodplain were main sources of omission error, and commission errors occurred primarily in pixels of mixed land use and along the flood edge. Nevertheless, the unsupervised nature of ICA

  19. EXACTITUD ESPACIAL EN LA CREACIÓN DE BASES DE DATOS SIG MODELOS RÁSTER Y VECTORIAL SPATIAL ACCURACY IN THE CREATION OF DATABASES GIS RASTER AND VECTOR MODELS

    Directory of Open Access Journals (Sweden)

    Carlos Mena Frau

    2008-06-01

    Full Text Available La exactitud en la representación espacial de elementos geográficos en una base de datos de un Sistema de Información Geográfica (SIG está sujeta a errores originados en los procesos de captura y procesamiento de los datos, lo cual queda en evidencia cuando se integra información más exacta. La cuantificación del error es fundamental cuando se pretende tomar decisiones sobre la base de la información disponible. En el estudio se establece una metodología para determinar y comparar el error de representación de elementos geográficos en los modelos vectorial y ráster. La base de datos incluye elementos puntuales, lineales y poligonales, que representan elementos reales correspondientes a una torre, un camino y un rodal. Esta información se obtuvo a partir de mediciones en terreno con el Sistema de Posicionamiento Global (GPS, que fueron procesadas para dar origen a coberturas en formato vectorial. Posteriormente, se realizó el traspaso de la información al formato ráster, empleando resoluciones de píxel de 5, 10 y 20 metros. Mediante un algoritmo matemático se determinaron coordenadas homólogas entre los elementos representados en los dos modelos. De la distancia euclidiana entre coordenadas homólogas, se obtuvo un error medio de representación para cada modelo que luego se utilizó para hacer un análisis estadístico de comparación de exactitud espacial entre los modelos. Los resultados obtenidos indican que no existen diferencias significativas en el error medio de los modelos vectorial y ráster, pero sí existen diferencias en los errores medios arrojados para las distintas resoluciones empleadas en la rasterización de la información original.Representation spatial accuracy of geographic elements in a Geographic Information System (GIS database is subject to errors generated in the processes of data capture and processing, which is in evidence when more exact information is integrated. Error quantification is

  20. Rice crop mapping and change prediction using multi-temporal satellite images in the Mekong Delta, Vietnam

    Science.gov (United States)

    Chen, C. R.; Chen, C. F.; Nguyen, S. T.

    2014-12-01

    The rice cropping systems in the Vietnamese Mekong Delta (VMD) has been undergoing major changes to cope with developing agro-economics, increasing population and changing climate. Information on rice cropping practices and changes in cropping systems is critical for policymakers to devise successful strategies to ensure food security and rice grain exports for the country. The primary objective of this research is to map rice cropping systems and predict future dynamics of rice cropping systems using the MODIS time-series data of 2002, 2006, and 2010. First, a phenology-based classification approach was applied for the classification and assessment of rice cropping systems in study region. Second, the Cellular Automata-Markov (CA-Markov) models was used to simulate the rice-cropping system map of VMD for 2010. The comparisons between the classification maps and the ground reference data indicated satisfactory results with overall accuracies and Kappa coefficients, respectively, of 81.4% and 0.75 for 2002, 80.6% and 0.74 for 2006 and 85.5% and 0.81 for 2010. The simulated map of rice cropping system for 2010 was extrapolated by CA-Markov model based on the trend of rice cropping systems during 2002~2006. The comparison between predicted scenario and classification map for 2010 presents a reasonably closer agreement. In conclusion, the CA-Markov model performs a powerful tool for the dynamic modeling of changes in rice cropping systems, and the results obtained demonstrate that the approach produces satisfactory results in terms of accuracy, quantitative forecast and spatial pattern changes. Meanwhile, the projections of the future changes would provide useful inputs to the agricultural policy for effective management of the rice cropping practices in VMD.

  1. Quantifying Land Use Change in Zhejiang Coastal Region, China Using Multi-Temporal Landsat TM/ETM+ Images

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images in 1985, 1986, 1993, 1994and 2001 were used to quantify the land use and land cover changes (LUCC) in the Zhejiang coastal region with a stratified unsupervised classification technique in conjunction with visual interpretation and to attempt an identification of the socioeconomic driving forces. In level Ⅰ an overall accurate classification was achieved using a modified Anderson's Ⅰ/Ⅱ/Ⅲ-level classification scheme. The overall accuracy of the land use classification at Anderson level I were 89.7%(1985), 91.6% (1993), and 90.4% (2001). The most rapid land use change was a dramatic increase in urban or built-up areas, which quadrupled from 1985 to 2001. Over 90% of this newly expanded built-up area was originally paddy fields or other croplands. In different parts of the Zhejiang coastal region, urban land expansion was spatially uneven. Temporally,land use development did not stabilized, and the two study periods of time (1985-1993 and 1993-2001) had different transition styles. Socioeconomic factors, such as gross domestic product, total population, and financial expenditure, were all highly correlated with the expansion of urban or built-up areas. Based on the degree of urban sprawl and socioeconomic factors, cities and towns were further divided into six subgroups, which may help decision makers improve land use for the region.

  2. Application of a regularized model inversion system (REGFLEC) to multi-temporal RapidEye imagery for retrieving vegetation characteristics

    Science.gov (United States)

    Houborg, Rasmus; McCabe, Matthew F.

    2015-10-01

    Accurate retrieval of canopy biophysical and leaf biochemical constituents from space observations is critical to diagnosing the functioning and condition of vegetation canopies across spatio-temporal scales. Retrieved vegetation characteristics may serve as important inputs to precision farming applications and as constraints in spatially and temporally distributed model simulations of water and carbon exchange processes. However significant challenges remain in the translation of composite remote sensing signals into useful biochemical, physiological or structural quantities and treatment of confounding factors in spectrum-trait relations. Bands in the red-edge spectrum have particular potential for improving the robustness of retrieved vegetation properties. The development of observationally based vegetation retrieval capacities, effectively constrained by the enhanced information content afforded by bands in the red-edge, is a needed investment towards optimizing the benefit of current and future satellite sensor systems. In this study, a REGularized canopy reFLECtance model (REGFLEC) for joint leaf chlorophyll (Chll) and leaf area index (LAI) retrieval is extended to sensor systems with a band in the red-edge region for the first time. Application to time-series of 5 m resolution multi-spectral RapidEye data is demonstrated over an irrigated agricultural region in central Saudi Arabia, showcasing the value of satellite-derived crop information at this fine scale for precision management. Validation against in-situ measurements in fields of alfalfa, Rhodes grass, carrot and maize indicate improved accuracy of retrieved vegetation properties when exploiting red-edge information in the model inversion process.

  3. Land use change detection and impact assessment in Anzali international coastal wetland using multi-temporal satellite images.

    Science.gov (United States)

    Mousazadeh, Roya; Ghaffarzadeh, Hamidreza; Nouri, Jafar; Gharagozlou, Alireza; Farahpour, Mehdi

    2015-12-01

    Anzali is one of the 18 Iranian wetlands of international importance listed in Ramsar Convention. This unique ecosystem in the world with high ecological diversity is highly threatened by various factors such as pollutants, sedimentation, unauthorized development of urban infrastructure, over-harvesting of wetland resources, land use changes, and invasive species. Among which, one of the most challenging destructive factors, land use change, was scrutinized in this study. For this, remotely sensed data and Geographical Information System (GIS) were used to detect land changes and corresponding impacts on the study area over a 38-year period from 1975 to 2013.. Changes in the study area were traced in five dominant land-use classes at four time intervals of 1975, 1989, 2007, and 2013. Accordingly, changes in different categories were quantified using satellite images. The methodology adopted in this study includes an integrated approach of supervised classification, zonal and object-oriented image analyses. According to the Kappa coefficient of 0.84 for the land use map of 2013, the overall accuracy of the method was estimated at 89%, which indicated that this method can be useful for monitoring and behavior analysis of other Iranian wetlands. The obtained results revealed extensive land use changes over the study period. As the results suggest, between the years 1975 to 2013, approximately 6500 ha (∼69%) rangeland area degraded. Further, urban and agricultural areas have been extended by 2982 ha (∼74%) and 2228 ha (∼6%), respectively. This could leave a negative impact on water quality of the wetland.

  4. Application of a regularized model inversion system (REGFLEC) to multi-temporal RapidEye imagery for retrieving vegetation characteristics

    KAUST Repository

    Houborg, Rasmus

    2015-10-14

    Accurate retrieval of canopy biophysical and leaf biochemical constituents from space observations is critical to diagnosing the functioning and condition of vegetation canopies across spatio-temporal scales. Retrieved vegetation characteristics may serve as important inputs to precision farming applications and as constraints in spatially and temporally distributed model simulations of water and carbon exchange processes. However significant challenges remain in the translation of composite remote sensing signals into useful biochemical, physiological or structural quantities and treatment of confounding factors in spectrum-trait relations. Bands in the red-edge spectrum have particular potential for improving the robustness of retrieved vegetation properties. The development of observationally based vegetation retrieval capacities, effectively constrained by the enhanced information content afforded by bands in the red-edge, is a needed investment towards optimizing the benefit of current and future satellite sensor systems. In this study, a REGularized canopy reFLECtance model (REGFLEC) for joint leaf chlorophyll (Chll) and leaf area index (LAI) retrieval is extended to sensor systems with a band in the red-edge region for the first time. Application to time-series of 5 m resolution multi-spectral RapidEye data is demonstrated over an irrigated agricultural region in central Saudi Arabia, showcasing the value of satellite-derived crop information at this fine scale for precision management. Validation against in-situ measurements in fields of alfalfa, Rhodes grass, carrot and maize indicate improved accuracy of retrieved vegetation properties when exploiting red-edge information in the model inversion process. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

  5. Spatial and multi-temporal analysis of deforestation and quantification of the remnant forests on Porto Rico Island, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    João Batista Campos

    1999-01-01

    Full Text Available The process of land occupation by the state of Paraná practically decimated its forests. Presently, only 7% from a total area of 83.41% is covered by forests. Most of them are now concentrated in the "Serra do Mar" and in the Iguaçu National Park. With regard to forest cover the most critical region is situated in the northwestern of the state with less than 1% of its area covered by forest. This restricted area mainly consists of conservation units and the islands of the high Paraná River floodplain. The present study consists of a spatial and multi-temporal analysis of deforestation and the quantification of the remnant forests on Porto Rico island (22º45'S; 53º15'W, which have their occupation history linked to the colonization process of the region. Historical aerial photographs of this region were used and the relationship of deforestation with the process of colonization and social transformation of the region is discussed.O processo de ocupação das terras do Paraná praticamente dizimou as florestas do Estado, que originalmente possuía 83,41% de sua área total coberta com florestas. Atualmente remanescem aproximadamente 7% da área com florestas, concentradas na Serra do Mar e no Parque Nacional do Iguaçu. Na região noroeste, a situação é mais crítica, com menos de 1% de sua área coberta por florestas, concentradas, principalmente, em unidades de conservação e nas ilhas da planície de inundação do alto rio Paraná. Esta planície é formada por uma ampla calha aluvial, com inúmeros canais, lagoas e ilhas, que têm sua história de ocupação ligadas ao processo de colonização na região. Neste trabalho, é realizada uma análise espacial e multi-temporal dos desflorestamentos e uma quantificação das florestas remanescentes da ilha Porto Rico (22º45'S; 53º15'W, por meio de fotografias aéreas históricas da região e discutidas as relações destes desflorestamentos com os processo de colonização e transforma

  6. An automatic fuzzy-based multi-temporal brain digital subtraction angiography image fusion algorithm using curvelet transform and content selection strategy.

    Science.gov (United States)

    Momeni, Saba; Pourghassem, Hossein

    2014-08-01

    Recently image fusion has prominent role in medical image processing and is useful to diagnose and treat many diseases. Digital subtraction angiography is one of the most applicable imaging to diagnose brain vascular diseases and radiosurgery of brain. This paper proposes an automatic fuzzy-based multi-temporal fusion algorithm for 2-D digital subtraction angiography images. In this algorithm, for blood vessel map extraction, the valuable frames of brain angiography video are automatically determined to form the digital subtraction angiography images based on a novel definition of vessel dispersion generated by injected contrast material. Our proposed fusion scheme contains different fusion methods for high and low frequency contents based on the coefficient characteristic of wrapping second generation of curvelet transform and a novel content selection strategy. Our proposed content selection strategy is defined based on sample correlation of the curvelet transform coefficients. In our proposed fuzzy-based fusion scheme, the selection of curvelet coefficients are optimized by applying weighted averaging and maximum selection rules for the high frequency coefficients. For low frequency coefficients, the maximum selection rule based on local energy criterion is applied to better visual perception. Our proposed fusion algorithm is evaluated on a perfect brain angiography image dataset consisting of one hundred 2-D internal carotid rotational angiography videos. The obtained results demonstrate the effectiveness and efficiency of our proposed fusion algorithm in comparison with common and basic fusion algorithms.

  7. Recent changes in Imja Glacial Lake and its damming moraine in the Nepal Himalaya revealed by in situ surveys and multi-temporal ASTER imagery

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Koji; Sakai, Akiko; Nuimura, Takayuki [Graduate School of Environmental Studies, Nagoya University, Nagoya 464-8601 (Japan); Yamaguchi, Satoru [Snow and Ice Research Center, National Research Institute for Earth Science and Disaster Prevention, Nagaoka 940-0821 (Japan); Sharma, Rishi R [Department of Hydrology and Meteorology, Ministry of Environment, Science and Technology, Babar Mahal, Kathmandu (Nepal)

    2009-10-15

    Changes in the area and bathymetry of Imja Glacial Lake and in the elevation of its damming moraine, Khumbu region, Nepal Himalaya are investigated. Previously reported changes in the lake area have been updated by multi-temporal ASTER images, which revealed a decreased expansion rate after 2000. A provisional expansion of the lake observed in 2004, from which some studies concluded an accelerated lake expansion due to global warming, has, from 2005, subsided to the glacier surface. Bathymetric changes for the period 1992-2002 that were first obtained for Himalayan glacial lakes suggest that the melting of debris-covered ice beneath the lake is insignificant in terms of the increase in lake volume, and that the retreat of a glacier in contact with the lake by calving is essential for the lake's expansion. Changes in the height of a damming moraine for the period 2001-2007 suggest a continuous surface lowering near the lake, though the lowering rates are smaller than those for the period 1989-1994.

  8. Utilization of multi-temporal landsat imagery for analyzing land Use/Cover changes and urban expansion of Nakhon Rachasima City

    Directory of Open Access Journals (Sweden)

    Prach Sangthongwattanakul

    2014-03-01

    Full Text Available One of important causes to climate change is land use/ land cover changes due to their important role in the amount of carbon dioxide in the atmosphere which directly relate to a solution to the problem of global warming. Analysis of land use/ land cover changes is thus very important for developing countries such as Thailand, especially to study the trend of land use/land cover changes that can be used for investigation of theirs driving forces. In addition, during these four decades, land use/cover in Nakhon Ratchasima city, a metropolitan city in Northeastern Thailand, has been rapidly changes because of rapid economical growth together with its location situated in the central of Northeastern Thailand. This study aims to determine land use/cover changes pattern of the Nakhon Ratchasima city. We employed unsupervised classification approach coupled with GIS analyses was employed to generate land use/cover maps for 1972, 2002 and 2013 with four classes; vegetated areas, settlement areas, barelands and water resoures. The results indicate that urban areas have increased based on economic and population growth as well as road network extension and consequently the urban growth affected environmental conditions. In the study, with multi-temporal Landsat data, we successfully used remote sensing techniques together with information technology as a tool for effectively monitoring urban growth.

  9. Automated Extraction of Inundated Areas from Multi-Temporal Dual-Polarization RADARSAT-2 Images of the 2011 Central Thailand Flood

    Directory of Open Access Journals (Sweden)

    Pisut Nakmuenwai

    2017-01-01

    Full Text Available This study examines a novel extraction method for SAR imagery data of widespread flooding, particularly in the Chao Phraya river basin of central Thailand, where flooding occurs almost every year. Because the 2011 flood was among the largest events and of a long duration, a large number of satellites observed it, and imagery data are available. At that time, RADARSAT-2 data were mainly used to extract the affected areas by the Thai government, whereas ThaiChote-1 imagery data were also used as optical supporting data. In this study, the same data were also employed in a somewhat different and more detailed manner. Multi-temporal dual-polarized RADARSAT-2 images were used to classify water areas using a clustering-based thresholding technique, neighboring valley-emphasis, to establish an automated extraction system. The novel technique has been proposed to improve classification speed and efficiency. This technique selects specific water references throughout the study area to estimate local threshold values and then averages them by an area weight to obtain the threshold value for the entire area. The extracted results were validated using high-resolution optical images from the GeoEye-1 and ThaiChote-1 satellites and water elevation data from gaging stations.

  10. Comparison of multi-temporal NOAA-AVHRR and SPOT-XS satellite data for mapping land-cover dynamics in the West African Sahel

    Science.gov (United States)

    Marsh, S. E.; Walsh, J. L.; Lee, C. T.; Beck, L. R.; Hutchinson, C. F.

    1992-01-01

    Multi-resolution and multi-temporal remote sensing data (SPOT-XS and AVHRR) were evaluated for mapping local land-cover dynamics in the Sahel of West Africa. The aim of this research was to evaluate the agricultural information that could be derived from both high and low spatial resolution data in areas where there is very often limited ground information. A combination of raster-based image processing and vector-based geographical information system mapping was found to be effective for understanding both spatial and spectral land-cover dynamics. The SPOT data proved useful for mapping local land-cover classes in a dominantly recessive agricultural region. The AVHRR-LAC data could be used to map the dynamics of riparian vegetation, but not the changes associated with recession agriculture. In areas where there was a complex mixture of recession and irrigated agriculture, as well as riparian vegetation, the AVHRR data did not provide an accurate temporal assessment of vegetation dynamics.

  11. Backscatter Analysis Using Multi-Temporal and Multi-Frequency SAR Data in the Context of Flood Mapping at River Saale, Germany

    Directory of Open Access Journals (Sweden)

    Sandro Martinis

    2015-06-01

    Full Text Available In this study, an analysis of multi-temporal and multi-frequency Synthetic Aperture Radar data is performed to investigate the backscatter behavior of various semantic classes in the context of flood mapping in central Europe. The focus is mainly on partially submerged vegetation such as forests and agricultural fields. The test area is located at River Saale, Saxony-Anhalt, Germany, which is covered by a time series of 39 TerraSAR-X data acquired within the time interval December 2009 to June 2013. The data set is supplemented by ALOS PALSAR L-band and RADARSAT-2 C-band data. The time series covers two inundations in January 2011 and June 2013 which allows evaluating backscatter variations between flood periods and normal water level conditions using different radar wavelengths. According to the results, there is potential in detecting flooding beneath vegetation in all microwave wavelengths, even in X-band for sparse vegetation or leaf-off forests.

  12. Data management of multi-temporal images for remote sensing information services in oil and gas application%面向石油遥感信息服务的多时相影像数据管理

    Institute of Scientific and Technical Information of China (English)

    郭红燕; 邹立群; 张友焱; 刘扬; 董文彤; 周红英

    2016-01-01

    在石油遥感应用中,多时相数据的应用面非常广,如何对不同应用中大量的多时相成果影像进行有效管理是一个迫切需要解决的问题。应用三维地理信息技术,采用两套数据分体管理模式,在三维基础影像数据的基础上,设计了一个实用的多时相数据存储结构,该模式充分考虑了石油遥感应用中多时相数据的多应用专题、多地区或事件、多数据源、多时相的特点,建立了基于三维地理信息的多时相数据管理系统,初步实现了面向石油遥感信息服务的多时相数据的有效管理。%In the application of remote sensing to petroleum exploration, multi-temporal images are very commonly used. How to manage effectively the massive multi -temporal images to satisfy diverse applications is an urgent problem to be solved. The authors firstly employ separate - management mode for two - set data in three -dimensional GIS. Based on the fundamental image data of three-dimensional GIS, the authors present a practical data storage model of multi-temporal images suitable to solving complicated data features,which is characterized by multi-application, multi -district or event, multi -data resource, multi -temporal in providing RS Information service for oil application. This research is verified by developing a multi -temporal images data management system to provide remote sensing multi-temporal images information service.

  13. Assessing the Accuracy of High Resolution Digital Surface Models Computed by PhotoScan ® and MicMac ® in Sub-Optimal Survey Conditions

    OpenAIRE

    Marion Jaud; Sophie Passot; Réjanne Le Bivic; Christophe Delacourt; Philippe Grandjean; Nicolas Le Dantec

    2016-01-01

    International audience; For monitoring purposes and in the context of geomorphological research, Unmanned Aerial Vehicles (UAV) appear to be a promising solution to provide multi-temporal Digital Surface Models (DSMs) and orthophotographs. There are a variety of photogrammetric software tools available for UAV-based data. The objective of this study is to investigate the level of accuracy that can be achieved using two of these software tools: Agisoft PhotoScan ® Pro and an open-source altern...

  14. Relational databases

    CERN Document Server

    Bell, D A

    1986-01-01

    Relational Databases explores the major advances in relational databases and provides a balanced analysis of the state of the art in relational databases. Topics covered include capture and analysis of data placement requirements; distributed relational database systems; data dependency manipulation in database schemata; and relational database support for computer graphics and computer aided design. This book is divided into three sections and begins with an overview of the theory and practice of distributed systems, using the example of INGRES from Relational Technology as illustration. The

  15. Biofuel Database

    Science.gov (United States)

    Biofuel Database (Web, free access)   This database brings together structural, biological, and thermodynamic data for enzymes that are either in current use or are being considered for use in the production of biofuels.

  16. Onzekere databases

    NARCIS (Netherlands)

    van Keulen, Maurice

    Een recente ontwikkeling in het databaseonderzoek betret zogenaamde 'onzekere databases'. Dit artikel beschrijft wat onzekere databases zijn, hoe ze gebruikt kunnen worden en welke toepassingen met name voordeel zouden kunnen hebben van deze technologie.

  17. Community Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This excel spreadsheet is the result of merging at the port level of several of the in-house fisheries databases in combination with other demographic databases such...

  18. Regional heavy metal pollution in crops by integrating physiological function variability with spatio-temporal stability using multi-temporal thermal remote sensing

    Science.gov (United States)

    Liu, Meiling; Liu, Xiangnan; Zhang, Biyao; Ding, Chao

    2016-09-01

    Heavy metal stress in crops is characterized by stability in space and time, which differs from other stressors that are typically more transient (e.g., drought, pests/diseases, and mismanagement). The objective of this study is to assess regional heavy metal stress in rice by integrating physiological function variability with spatio-temporal stability based on multi-temporal thermal infrared (TIR) remote sensing images. The field in which the experiment was conducted is located in Zhuzhou City, Hunan Province, China. HJ-1B images and in-situ measured data were collected from rice growing in heavy metal contaminated soils. A stress index (SI) was devised as an indicator for the degree of heavy metal stress of the rice in different growth stages, and a time-spectrum feature space (TSFS) model was used to determine rice heavy metal stress levels. The results indicate that (i) SI is a good indicator of rice damage caused by heavy metal stress. Minimum values of SI occur in rice subject to high pollution, followed by larger SI with medium pollution and maximum SI for low pollution, for the same growth stage. (ii) SI shows some variation for different growth stages of rice, and the minimum SI occurs at the flowering stage. (iii) The TSFS model is successful at identifying rice heavy metal stress, and stress levels in rice stabilized regardless of the model being applied in the two different years. This study suggests that regional heavy metal stress in crops can be accurately detected using TIR technology, if a sensitive indicator of crop physiological function impairment is used and an effective model is selected. A combination of spectrum and spatio-temporal information appears to be a very promising method for monitoring crops with various stressors.

  19. A Method for Estimating the Aerodynamic Roughness Length with NDVI and BRDF Signatures Using Multi-Temporal Proba-V Data

    Directory of Open Access Journals (Sweden)

    Mingzhao Yu

    2016-12-01

    Full Text Available Aerodynamic roughness length is an important parameter for surface fluxes estimates. This paper developed an innovative method for estimation of aerodynamic roughness length (z0m over farmland with a new vegetation index, the Hot-darkspot Vegetation Index (HDVI. To obtain this new index, the normalized-difference hot-darkspot index (NDHD is introduced using a semi-empirical, kernel-driven bidirectional reflectance model with multi-temporal Proba-V 300-m top-of-canopy (TOC reflectance products. A linear relationship between HDVI and z0m was found during the crop growth period. Wind profiles data from two field automatic weather station (AWS were used to calibrate the model: one site is in Guantao County in Hai Basin, in which double-cropping systems and crop rotations with summer maize and winter wheat are implemented; the other is in the middle reach of the Heihe River Basin from the Heihe Watershed Allied Telemetry Experimental Research (HiWATER project, with the main crop of spring maize. The iterative algorithm based on Monin–Obukhov similarity theory is employed to calculate the field z0m from time series. Results show that the relationship between HDVI and z0m is more pronounced than that between NDVI and z0m for spring maize at Yingke site, with an R2 value that improved from 0.636 to 0.772. At Guantao site, HDVI also exhibits better performance than NDVI, with R2 increasing from 0.630 to 0.793 for summer maize and from 0.764 to 0.790 for winter wheat. HDVI can capture the impacts of crop residue on z0m, whereas NDVI cannot.

  20. Monitoring mangrove forest dynamics of the Sundarbans in Bangladesh and India using multi-temporal satellite data from 1973 to 2000

    Science.gov (United States)

    Giri, C.; Pengra, B.; Zhu, Z.; Singh, A.; Tieszen, L.L.

    2007-01-01

    Mangrove forests in many parts of the world are declining at an alarming rate-possibly even more rapidly than inland tropical forests. The rate and causes of such changes are not known. The forests themselves are dynamic in nature and are undergoing constant changes due to both natural and anthropogenic forces. Our research objective was to monitor deforestation and degradation arising from both natural and anthropogenic forces. We analyzed multi-temporal satellite data from 1970s, 1990s, and 2000s using supervised classification approach. Our spatio-temporal??analysis shows that despite having the highest population density in the world in its periphery, areal extent of the mangrove forest of the Sundarbans has not changed significantly (approximately 1.2%) in the last ???25 years. The forest is however constantly changing due to erosion, aggradation, deforestation and mangrove rehabilitation programs. The net forest area increased by 1.4% from the 1970s to 1990 and decreased by 2.5% from 1990 to 2000. The change is insignificant in the context of classification errors and the dynamic nature of mangrove forests. This is an excellent example of the co-existence of humans with terrestrial and aquatic plant and animal life. The strong commitment of governments under various protection measures such as forest reserves, wildlife sanctuaries, national parks, and international designations, is believed to be responsible for keeping this forest relatively intact (at least in terms of area). While the measured net loss of mangrove forest is not that high, the change matrix shows that turnover due to erosion, aggradation, reforestation and deforestation was much greater than net change. The forest is under threat from natural and anthropogenic forces leading to forest degradation, primarily due to top-dying disease and over-exploitation of forest resources. ?? 2007 Elsevier Ltd. All rights reserved.

  1. Monitoring mangrove forest dynamics of the Sundarbans in Bangladesh and India using multi-temporal satellite data from 1973 to 2000

    Science.gov (United States)

    Giri, Chandra; Pengra, Bruce; Zhu, Zhiliang; Singh, Ashbindu; Tieszen, Larry L.

    2007-06-01

    Mangrove forests in many parts of the world are declining at an alarming rate—possibly even more rapidly than inland tropical forests. The rate and causes of such changes are not known. The forests themselves are dynamic in nature and are undergoing constant changes due to both natural and anthropogenic forces. Our research objective was to monitor deforestation and degradation arising from both natural and anthropogenic forces. We analyzed multi-temporal satellite data from 1970s, 1990s, and 2000s using supervised classification approach. Our spatio-temporal analysis shows that despite having the highest population density in the world in its periphery, areal extent of the mangrove forest of the Sundarbans has not changed significantly (approximately 1.2%) in the last ˜25 years. The forest is however constantly changing due to erosion, aggradation, deforestation and mangrove rehabilitation programs. The net forest area increased by 1.4% from the 1970s to 1990 and decreased by 2.5% from 1990 to 2000. The change is insignificant in the context of classification errors and the dynamic nature of mangrove forests. This is an excellent example of the co-existence of humans with terrestrial and aquatic plant and animal life. The strong commitment of governments under various protection measures such as forest reserves, wildlife sanctuaries, national parks, and international designations, is believed to be responsible for keeping this forest relatively intact (at least in terms of area). While the measured net loss of mangrove forest is not that high, the change matrix shows that turnover due to erosion, aggradation, reforestation and deforestation was much greater than net change. The forest is under threat from natural and anthropogenic forces leading to forest degradation, primarily due to top-dying disease and over-exploitation of forest resources.

  2. Structural health monitoring of engineered structures using a space-borne synthetic aperture radar multi-temporal approach: from cultural heritage sites to war zones

    Science.gov (United States)

    Milillo, Pietro; Tapete, Deodato; Cigna, Francesca; Perissin, Daniele; Salzer, Jacqueline; Lundgren, Paul; Fielding, Eric; Burgmann, Roland; Biondi, Filippo; Milillo, Giovanni; Serio, Carmine

    2016-10-01

    Structural health monitoring (SHM) of engineered structures consists of an automated or semi-automated survey system that seeks to assess the structural condition of an anthropogenic structure. The aim of an SHM system is to provide insights into possible induced damage or any inherent signals of deformation affecting the structure in terms of detection, localization, assessment, and prediction. During the last decade there has been a growing interest in using several remote sensing techniques, such as synthetic aperture radar (SAR), for SHM. Constellations of SAR satellites with short repeat time acquisitions permit detailed surveys temporal resolution and millimetric sensitivity to deformation that are at the scales relevant to monitoring large structures. The all-weather multi-temporal characteristics of SAR make its products suitable for SHM systems, especially in areas where in situ measurements are not feasible or not cost effective. To illustrate this capability, we present results from COSMO-SkyMed (CSK) and TerraSAR-X SAR observations applied to the remote sensing of engineered structures. We show how by using multiple-geometry SAR-based products which exploit both phase and amplitude of the SAR signal we can address the main objectives of an SHM system including detection and localization. We highlight that, when external data such as rain or temperature records are available or simple elastic models can be assumed, the SAR-based SHM capability can also provide an interpretation in terms of assessment and prediction. We highlight examples of the potential for such imaging capabilities to enable advances in SHM from space, focusing on dams and cultural heritage areas.

  3. Database Administrator

    Science.gov (United States)

    Moore, Pam

    2010-01-01

    The Internet and electronic commerce (e-commerce) generate lots of data. Data must be stored, organized, and managed. Database administrators, or DBAs, work with database software to find ways to do this. They identify user needs, set up computer databases, and test systems. They ensure that systems perform as they should and add people to the…

  4. Database Administrator

    Science.gov (United States)

    Moore, Pam

    2010-01-01

    The Internet and electronic commerce (e-commerce) generate lots of data. Data must be stored, organized, and managed. Database administrators, or DBAs, work with database software to find ways to do this. They identify user needs, set up computer databases, and test systems. They ensure that systems perform as they should and add people to the…

  5. A multi-tier higher order Conditional Random Field for land cover classification of multi-temporal multi-spectral Landsat imagery

    CSIR Research Space (South Africa)

    Salmon, BP

    2015-07-01

    Full Text Available accuracy while keeping the computational costs tractable. We also expand the typical 1-tier protograph used in conventional CRFs to a 2-tier graph to encapsulate the temporal dimension. This further improves the classification accuracy by modeling...

  6. Multi-temporal study of BELVEDERE glacier for hydrologic hazard monitoring and water resource estimation using UAV: tests and first results

    Science.gov (United States)

    Piras, Marco; Cina, Alberto; De Michele, Carlo; Pinto, Livio; Barzaghi, Riccardo; Maschio, Paolo F.; Avanzi, Francesco; Bianchi, Alberto; Deidda, Cristina; Donizetti, Alberto; Giani, Giulia; Giarrizzo, Giuseppe; Negrini, Alessandro; Rampazzo, Alessandro; Savaia, Gianluca; Soria, Enrica

    2016-04-01

    2015. Eight flights were realized, covering about 2.7 km2; the images have been georeferenced through a series of ground control points, installed on the glacier and on surrounding moraines, which were measured with GNSS positioning (RTK or static). The images (> 1200) have been elaborated with different photogrammetric software, such as Agisoft PhotoScan, APS, LPS, Pix4D, in order to investigate the ratio quality of the product/ time consumption, with respect to hydrological purposes. The DSM obtained has been compared with other DSMs realized in the past years, making a multi-temporal analysis, and estimating the volumes' variations and trends of the glacier. Here, the activities will be described, including the field campaigns, data processing, and the first results obtained.

  7. Implications for the tectonic transition zone of active orogeny in Hoping drainage basin, by landscape evolution at the multi-temporal timescale

    Science.gov (United States)

    Chang, Q.; Chen, R. F.; Lin, W.; Hsieh, P. S.

    2015-12-01

    In an actively orogeny the landscape are transient state of disequilibrium in response to climatic and tectonic inputs. At the catchment scale, sensitivity of river systems plays an important role in landscape evolution. Hoping drainage basin is located at the tectonic transition zone in the north-eastern Taiwan, where the behavior of Philippine Sea plate switches from overriding above the east-dipping Eurasian Continental plate to northward subducting under the Ryukyu arc. However, extensive deep-seated landslides, debris flow, and numerous large alluvial terraces can be observed, suggesting strong surface processes in this watershed. This effect on regional climate fundamentally changed the landscape by reconfiguring drainage patterns and creating a vast influx of sediments into the basin. In this study we review the morphological evidence from multi-temporal timescale, including in-situ cosmogenic nuclides denudation rate and suspension load data, coupled with the analysis of the longitudinal profiles. The main goal of this study is to compare Holocene erosion rates with thermochronology and radiometric dating of river terraces to investigate the erosion history of Hoping area. The result shows that short-term erosion rate is around twice as large as the long-term denudation rate, which might due to the climate-driven erosion events such as typhoon-induced landslide. We've also mapped detail morphological features by using the high-resolution LiDAR image, which help us to identify not only the landslide but also tectonic features such as lineation, fault scarps, and fracture zones. The tectonic surface features and field investigation results show that the drainage basin is highly fractured, suggesting that even though the vertical tectonic activity rate is small, the horizontal shortening influenced by both southward opening of the back-arc Okinawa trough and the north-western collision in this area is significant. This might cause the reducing in rock strength

  8. Multi-Temporal Crop Surface Models Combined with the RGB Vegetation Index from Uav-Based Images for Forage Monitoring in Grassland

    Science.gov (United States)

    Possoch, M.; Bieker, S.; Hoffmeister, D.; Bolten, A.; Schellberg, J.; Bareth, G.

    2016-06-01

    Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs) were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition). Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI) was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based) and Esri ArcGIS. 14 ground control points (GCPs) were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon) with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass. There is a

  9. MULTI-TEMPORAL CROP SURFACE MODELS COMBINED WITH THE RGB VEGETATION INDEX FROM UAV-BASED IMAGES FOR FORAGE MONITORING IN GRASSLAND

    Directory of Open Access Journals (Sweden)

    M. Possoch

    2016-06-01

    Full Text Available Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition. Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based and Esri ArcGIS. 14 ground control points (GCPs were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass

  10. ENERGIC OD Geopan application using Virtual Hub: multi-temporal knowledge oriented information on built environment and riverbed changes to geologist community

    Science.gov (United States)

    Boldrini, E.; Brumana, R.; Previtali, M., Jr.; Mazzetti, P., Sr.; Cuca, B., Sr.; Barazzetti, L., Sr.; Camagni, R.; Santoro, M.

    2016-12-01

    The Built Environment (BE) is intended as the sum of natural and human activities in dynamic transformations in the past, in the present and in the future: it calls for more informed decisions to face the challenging threats (climate change, natural hazards, anthropic pressures) by exploiting resilience, sustainable intervention and tackling societal opportunities, as heritage valorization and tourism acknowledgment; thus, it asks for awareness rising among circular reflective society. In the framework of ENERGIC OD project (EU Network for Redistributing Geographic Information - Open Data), this paper describes the implementation of an application (GeoPAN Atl@s app) addressed to improve a circular multi-temporal knowledge oriented generation of information, able to integrate and take in account historic and current maps, as well as products of satellite image processing to understand on course and on coming phenomena and relating them with the ones occurred in the ancient and recent past in a diachronic approach. The app is focused on riverbeds-BE and knowledge generation for the detection of their changes by involving geologist community and providing to other user the retrieved information (architects and urban planner, tourists and citizen). Here is described the implementation of the app interfaced with the ENERGIC OD Virtual Hub component, based on a brokering framework for OD discovery and access, to assure interoperability and integration of different datasets, wide spread cartographic products with huge granularity (national, regional environmental Risk Maps, i.e. PAI, on site local data, i.e. UAV data, or results of Copernicus Programme satellite data processing, i.e. object-based and time series image analysis for riverbed monitoring using Sentinel2): different sources, scales and formats, including historical maps needing metadata generation, and SHP data used by the geologist in their daily activities for hydrogeological analysis, to be both usable as

  11. Register-based follow-up of social benefits and other transfer payments: accuracy and degree of completeness in a Danish interdepartmental administrative database compared with a population-based survey

    DEFF Research Database (Denmark)

    Hjøllund, Niels Henrik Ingvar; Andersen, Johan Hvid; Larsen, F. B.

    2007-01-01

    -related benefit (sickness benefit, vocational rehabilitation allowance, salary from subsidized jobs for persons with limited work capacity, anticipatory pension), 10.1% a voluntary retirement pension, while 74.4% had no record of transfer payment for that week. The predictive value of DREAM was 74.8% for health......-related transfer payment and 98.2% for self-support. Among persons with a record of sickness benefit, 52.4% reported no transfer payment. CONCLUSION: The DREAM database is feasible for follow-up of social and economic consequences of disease. Respondents may be unaware of payments transferred by the public...... authorities to the employer, and in such cases DREAM may be the best source of information. The database is useful for public health research, but may also be useful for socioeconomic analyses of selection bias and dropout from other studies...

  12. Database Manager

    Science.gov (United States)

    Martin, Andrew

    2010-01-01

    It is normal practice today for organizations to store large quantities of records of related information as computer-based files or databases. Purposeful information is retrieved by performing queries on the data sets. The purpose of DATABASE MANAGER is to communicate to students the method by which the computer performs these queries. This…

  13. Genome databases

    Energy Technology Data Exchange (ETDEWEB)

    Courteau, J.

    1991-10-11

    Since the Genome Project began several years ago, a plethora of databases have been developed or are in the works. They range from the massive Genome Data Base at Johns Hopkins University, the central repository of all gene mapping information, to small databases focusing on single chromosomes or organisms. Some are publicly available, others are essentially private electronic lab notebooks. Still others limit access to a consortium of researchers working on, say, a single human chromosome. An increasing number incorporate sophisticated search and analytical software, while others operate as little more than data lists. In consultation with numerous experts in the field, a list has been compiled of some key genome-related databases. The list was not limited to map and sequence databases but also included the tools investigators use to interpret and elucidate genetic data, such as protein sequence and protein structure databases. Because a major goal of the Genome Project is to map and sequence the genomes of several experimental animals, including E. coli, yeast, fruit fly, nematode, and mouse, the available databases for those organisms are listed as well. The author also includes several databases that are still under development - including some ambitious efforts that go beyond data compilation to create what are being called electronic research communities, enabling many users, rather than just one or a few curators, to add or edit the data and tag it as raw or confirmed.

  14. Database Replication

    CERN Document Server

    Kemme, Bettina

    2010-01-01

    Database replication is widely used for fault-tolerance, scalability and performance. The failure of one database replica does not stop the system from working as available replicas can take over the tasks of the failed replica. Scalability can be achieved by distributing the load across all replicas, and adding new replicas should the load increase. Finally, database replication can provide fast local access, even if clients are geographically distributed clients, if data copies are located close to clients. Despite its advantages, replication is not a straightforward technique to apply, and

  15. Probabilistic Databases

    CERN Document Server

    Suciu, Dan; Koch, Christop

    2011-01-01

    Probabilistic databases are databases where the value of some attributes or the presence of some records are uncertain and known only with some probability. Applications in many areas such as information extraction, RFID and scientific data management, data cleaning, data integration, and financial risk assessment produce large volumes of uncertain data, which are best modeled and processed by a probabilistic database. This book presents the state of the art in representation formalisms and query processing techniques for probabilistic data. It starts by discussing the basic principles for rep

  16. Dealer Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dealer reporting databases contain the primary data reported by federally permitted seafood dealers in the northeast. Electronic reporting was implemented May 1,...

  17. RDD Databases

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database was established to oversee documents issued in support of fishery research activities including experimental fishing permits (EFP), letters of...

  18. National database

    DEFF Research Database (Denmark)

    Kristensen, Helen Grundtvig; Stjernø, Henrik

    1995-01-01

    Artikel om national database for sygeplejeforskning oprettet på Dansk Institut for Sundheds- og Sygeplejeforskning. Det er målet med databasen at samle viden om forsknings- og udviklingsaktiviteter inden for sygeplejen.......Artikel om national database for sygeplejeforskning oprettet på Dansk Institut for Sundheds- og Sygeplejeforskning. Det er målet med databasen at samle viden om forsknings- og udviklingsaktiviteter inden for sygeplejen....

  19. Extracting land cover types in western Jilin based on multi-temporal remote sensing data%基于多时相遥感数据的吉林西部土地覆被分类提取

    Institute of Scientific and Technical Information of China (English)

    李晓东; 姜琦刚

    2016-01-01

    Recently, it’s still difficult to entirely replace the artificial visual interpretation for the computer automatic classification, which is used to extract land cover types' information from the remote sensing imagery, because the automatic method needs more efforts to improve the precision of the classification results. Furthermore, this problem has become the key joint of the automatic classification extraction. How to extract land cover types’ information in western area of Jilin, is one of the important problems, and the confused land cover types needs to be distinguished. The aim of this study is to deepen the application of remote sensing classification method that is used to extract land cover information automatically and quickly from the satellite imagery. The western area of Jilin is selected as the main research area. A new total solution to extract land cover information, based on the spatial variation theory, has been designed for the convenient automatic classification with the remote sensing technology. The remote sensing classification scheme is carried out by coding the R language algorithm and operating the remote sensing software ERDAS platform. The land cover types in Zhenlai County in the western area of Jilin, have been extracted and monitored through the combined utilization of 4 indices, including semivariance value of normalized difference vegetation index (NDVI) dataset, local variance of image texture, modified soil-adjusted vegetation index and normalized difference water index, which have significant meaning for the land cover types in the transition zone between cropping area and nomadic area. These variances have definite physical meaning (including vegetation, water, and soil drought conditions), so that the phenological information was used to build a multi-dimensional feature space classification data set. The results indicated that: 1) A total of 11 land cover types are extracted, using the multi-temporal remote sensing

  20. Biological Databases

    Directory of Open Access Journals (Sweden)

    Kaviena Baskaran

    2013-12-01

    Full Text Available Biology has entered a new era in distributing information based on database and this collection of database become primary in publishing information. This data publishing is done through Internet Gopher where information resources easy and affordable offered by powerful research tools. The more important thing now is the development of high quality and professionally operated electronic data publishing sites. To enhance the service and appropriate editorial and policies for electronic data publishing has been established and editors of article shoulder the responsibility.

  1. Accuracy Assessment of GEOV1 and MODIS C5 & C6 LAI and FAPAR Essential Climate Variables Products over a Network of Cropland Sites.

    Science.gov (United States)

    camacho De Coca, F.; Sánchez, J.; Latorre, C.; Lacaze, R. N.; Baret, F.; Weiss, M.

    2016-12-01

    This work discuss the accuracy of the LAI and FAPAR essential climate variables derived from satellite observations over a network of cropland sites mostly located in Europe. Three different LAI and FAPAR products are evaluated: GEOV1 from Copernicus Global Land Service derived from SPOT/VEGETATION and PROBA-V observations at 1 km spatial resolution, and the MODIS collection 5 derived at 1 km spatial resolution and the new collection 6 derived at 500m spatial resolution. The ground database was generated during the FP7 ImagineS project over a network of cropland sites, including some JECAM sites, in collaboration with local teams. A total of 66 field campaigns were conducted over 23 sites from january 2013 to march 2016 around the world (21 of them corresponding to croplands), sampling more than 1700 Elementary Sampling Units (ESUs) of about 20x20m size (more than 2000 measurements including replications with different devices). Most of the ESUs were characterized using digital hemispherical photos (DHP), as well as LAI-2200 and AccuPAR LP-80 devices, during the growing or mature period of the vegetation avoiding senescent, to be close to the definition of satellite LAI and FAPAR related to green foliar elements. The spatial sampling protocol follows the VALERI recommendations, with an stratified sampling per cover types in the study area of about 3x3 km2. Multi-temporal campaigns were performed in some of the sites, where in others only one campaign was conducted. Ground measurements were up-scaled by EOLAB using high-resolution imagery (mainly Landsat-8 data and SPOT-4) and robust regression methods testing the best band combination to minimize cross-validation and weighted RMS errors. This efforts resulted in a consistent an unique database of ground measurements and ground-based reference maps (between 38 and 48 depending on variable) generated following the standards of the CEOS/WGCV Land Products Validation, suitable to be used as fiducial reference for

  2. Extracting seasonal cropping patterns using multi-temporal vegetation indices from IRS LISS-III data in Muzaffarpur District of Bihar, India

    Directory of Open Access Journals (Sweden)

    Saptarshi Mondal

    2014-12-01

    Full Text Available The advancement in satellite technology in terms of spatial, temporal, spectral and radiometric resolutions leads, successfully, to more specific and intensified research on agriculture. Automatic assessment of spatio-temporal cropping pattern and extent at multi-scale (community level, regional level and global level has been a challenge to researchers. This study aims to develop a semi-automated approach using Indian Remote Sensing (IRS satellite data and associated vegetation indices to extract annual cropping pattern in Muzaffarpur district of Bihar, India at a fine scale (1:50,000. Three vegetation indices (VIs – NDVI, EVI2 and NDSBVI, were calculated using three seasonal (Kharif, Rabi and Zaid IRS Resourcesat 2 LISS-III images. Threshold reference values for vegetation and non-vegetation thematic classes were extracted based on 40 training samples over each of the seasonal VI. Using these estimated value range a decision tree was established to classify three seasonal VI stack images which reveals seven different cropping patterns and plantation. In addition, a digitised reference map was also generated from multi-seasonal LISS-III images to check the accuracy of the semi-automatically extracted VI based classified image. The overall accuracies of 86.08%, 83.1% and 83.3% were achieved between reference map and NDVI, EVI2 and NDSBVI, respectively. Plantation was successfully identified in all cases with 96% (NDVI, 95% (EVI2 and 91% (NDSBVI accuracy.

  3. Evaluating the trade-off between food and timber resulting from the conversion of Miombo forests to agricultural land in Angola using multi-temporal Landsat data.

    Science.gov (United States)

    Schneibel, Anne; Stellmes, Marion; Röder, Achim; Finckh, Manfred; Revermann, Rasmus; Frantz, David; Hill, Joachim

    2016-04-01

    The repopulation of abandoned areas in Angola after 27years of civil war led to a fast and extensive expansion of agricultural fields to meet the rising food demand. Yet, the increase in crop production at the expense of natural resources carries an inherent potential for conflicts since the demand for timber and wood extraction are also supposed to rise. We use the concept of ecosystem services to evaluate the trade-off between food and woody biomass. Our study area is located in central Angola, in the highlands of the upper Okavango catchment. We used Landsat data (spatial resolution: 30×30m) with a bi-temporal and multi-seasonal change detection approach for five time steps between 1989 and 2013 to estimate the conversion area from woodland to agriculture. Overall accuracy is 95%, user's accuracy varies from 89-95% and producer's accuracy ranges between 92-99%. To quantify the trade-off between woody biomass and the amount of food, this information was combined with indicator values and we furthermore assessed biomass regrowth on fallows. Our results reveal a constant rise in agricultural expansion from 1989-2013 with the mean annual deforestation rate increasing from roughly 5300ha up to about 12,000ha. Overall, 5.6% of the forested areas were converted to agriculture, whereas the FAO states a national deforestation rate for Angola of 5% from 1990-2010 (FAO, 2010). In the last time step 961,000t per year of woodland were cleared to potentially produce 1240t per year of maize. Current global agro-economical projections forecast increasing pressure on tropical dry forests from large-scale agriculture schemes (Gasparri et al., 2015; Searchinger and Heimlich, 2015). Our study underlines the importance of considering subsistence-related change processes, which may contribute significantly to negative effects associated with deforestation and degradation of these forest ecosystems.

  4. Audit of the Danish national vascular database

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Jensen, L P; Schroeder, T V

    1996-01-01

    The accuracy of data contained in the Danish vascular database was compared with the case notes. A total of 100 case notes were reviewed for 11 pertinent variables in the database. A high error rate ranging from 2 to 34% was found. Also, approximately 10% of patients had never been entered into t...

  5. Teknik Cepat Identifikasi Lahan Terbuka Melalui Citra Multi Temporal dan Multi Spasial (Quick Tecniques in Indentifying Open Area by the Use of Multi Spatial and Multidate Imageries

    Directory of Open Access Journals (Sweden)

    Ahyar Gunawan

    2010-12-01

    Full Text Available This study describes the use of multitemporal principal component analysis (MPCA and vegetation indexdifferencing (VIDN techniques in identifying open area on post-coal-mining sites using multi spatial and multidateof Landsat TM and SPOT 4 XS imageries. The study revealed that the synthetic images derived from stablebrightness, stable greenness,s and delta brightness of MPCA summarize information on post-coal-mining openedareas provided overall accuracy of 76.47% for the new ex mining area and 32.69% for old ex mining area. TheVIDN method provided relatively lower accuracy than those from MPCA i.e. 58.87% for new ex mining and13.25% for old ex-mining areas. The study also concluded that identifying open area on post-coal-mining sitesusing imageries was more efficient than using only ground survey, providing cost efficiency of 29%. Thisindicates that the cost required using satellite image is only 29% of the cost required for ground survey. Thestudy concluded that MPCA is better than VIDN for identifying open area on post-coal-mining sites.

  6. More Data and Better Tools for the GLIMS Glacier Database

    Science.gov (United States)

    Raup, B. H.; Armstrong, R. L.; Cogley, J. G.; Hock, R.

    2015-12-01

    Earth's glaciers are changing rapidly in response to a changing climate, and this has implications for people in numerous ways, such as increased hazards from glacial lake outburst floods, changes to water resources, and increasing sea level. To understand these changes, it is vitally important to monitor glaciers through time, measuring their areal extent, changes in volume, flow velocities, snow lines, elevation distribution, and changes to associated water bodies. The glacier database of the Global Land Ice Measurements from Space (GLIMS) initiative is the only multi-temporal glacier database capable of tracking all these glacier measurements and providing them to the scientific community and broader public.This contribution presents recent results in 1) expansion of the GLIMS Glacier Database in geographic coverage by drawing on the Randolph Glacier Inventory (RGI) and other new data sets; 2) new tools for visualizing and downloading GLIMS data in a choice of formats and data models; 3) a new data model for handling multiple glacier records through time while avoiding double-counting of glacier number or area; and 4) a new system of collaboration between all members of the glacier mapping community to streamline the process of meeting various community needs. The result of this work promises to be an improved glacier data repository that will be useful for tracking changes in water resources, hazards, and mass budgets of the world's glaciers.

  7. Assessing the Accuracy of High Resolution Digital Surface Models Computed by PhotoScan® and MicMac® in Sub-Optimal Survey Conditions

    OpenAIRE

    Marion Jaud; Sophie Passot; Réjanne Le Bivic; Christophe Delacourt; Philippe Grandjean; Nicolas Le Dantec

    2016-01-01

    For monitoring purposes and in the context of geomorphological research, Unmanned Aerial Vehicles (UAV) appear to be a promising solution to provide multi-temporal Digital Surface Models (DSMs) and orthophotographs. There are a variety of photogrammetric software tools available for UAV-based data. The objective of this study is to investigate the level of accuracy that can be achieved using two of these software tools: Agisoft PhotoScan® Pro and an open-source alternative, IGN© MicMac®, in s...

  8. Integrating age in the detection and mapping of incongruous patches in coffee (Coffea arabica) plantations using multi-temporal Landsat 8 NDVI anomalies

    Science.gov (United States)

    Chemura, Abel; Mutanga, Onisimo; Dube, Timothy

    2017-05-01

    The development of cost-effective, reliable and easy to implement crop condition monitoring methods is urgently required for perennial tree crops such as coffee (Coffea arabica), as they are grown over large areas and represent long term and higher levels of investment. These monitoring methods are useful in identifying farm areas that experience poor crop growth, pest infestation, diseases outbreaks and/or to monitor response to management interventions. This study compares field level coffee mean NDVI and LSWI anomalies and age-adjusted coffee mean NDVI and LSWI anomalies in identifying and mapping incongruous patches across perennial coffee plantations. To achieve this objective, we first derived deviation of coffee pixels from the global coffee mean NDVI and LSWI values of nine sequential Landsat 8 OLI image scenes. We then evaluated the influence of coffee age class (young, mature and old) on Landsat-scale NDVI and LSWI values using a one-way ANOVA and since results showed significant differences, we adjusted NDVI and LSWI anomalies for age-class. We then used the cumulative inverse distribution function (α ≤ 0.05) to identify fields and within field areas with excessive deviation of NDVI and LSWI from the global and the age-expected mean for each of the Landsat 8 OLI scene dates spanning three seasons. Results from accuracy assessment indicated that it was possible to separate incongruous and healthy patches using these anomalies and that using NDVI performed better than using LSWI for both global and age-adjusted mean anomalies. Using the age-adjusted anomalies performed better in separating incongruous and healthy patches than using the global mean for both NDVI (Overall accuracy = 80.9% and 68.1% respectively) and for LSWI (Overall accuracy = 68.1% and 48.9% respectively). When applied to other Landsat 8 OLI scenes, the results showed that the proportions of coffee fields that were modelled incongruent decreased with time for the young age category and

  9. Comparison of Object-Based Image Analysis Approaches to Mapping New Buildings in Accra, Ghana Using Multi-Temporal QuickBird Satellite Imagery

    Directory of Open Access Journals (Sweden)

    Yu Hsin Tsai

    2011-12-01

    Full Text Available The goal of this study was to map and quantify the number of newly constructed buildings in Accra, Ghana between 2002 and 2010 based on high spatial resolution satellite image data. Two semi-automated feature detection approaches for detecting and mapping newly constructed buildings based on QuickBird very high spatial resolution satellite imagery were analyzed: (1 post-classification comparison; and (2 bi-temporal layerstack classification. Feature Analyst software based on a spatial contextual classifier and ENVI Feature Extraction that uses a true object-based image analysis approach of image segmentation and segment classification were evaluated. Final map products representing new building objects were compared and assessed for accuracy using two object-based accuracy measures, completeness and correctness. The bi-temporal layerstack method generated more accurate results compared to the post-classification comparison method due to less confusion with background objects. The spectral/spatial contextual approach (Feature Analyst outperformed the true object-based feature delineation approach (ENVI Feature Extraction due to its ability to more reliably delineate individual buildings of various sizes. Semi-automated, object-based detection followed by manual editing appears to be a reliable and efficient approach for detecting and enumerating new building objects. A bivariate regression analysis was performed using neighborhood-level estimates of new building density regressed on a census-derived measure of socio-economic status, yielding an inverse relationship with R2 = 0.31 (n = 27; p = 0.00. The primary utility of the new building delineation results is to support spatial analyses of land cover and land use and demographic change.

  10. Protein-Protein Interaction Databases

    DEFF Research Database (Denmark)

    Szklarczyk, Damian; Jensen, Lars Juhl

    2015-01-01

    of research are explored. Here we present an overview of the most widely used protein-protein interaction databases and the methods they employ to gather, combine, and predict interactions. We also point out the trade-off between comprehensiveness and accuracy and the main pitfall scientists have to be aware......Years of meticulous curation of scientific literature and increasingly reliable computational predictions have resulted in creation of vast databases of protein interaction data. Over the years, these repositories have become a basic framework in which experiments are analyzed and new directions...

  11. Multi-temporal monitoring of crack formation on a mountain col with low-cost unmanned aerial systems - a case study in Austria

    Science.gov (United States)

    Stary, Ulrike; Adams, Marc

    2016-04-01

    In the Tuxer Alps of Western Austria, crack formation was observed on a col at approximately 2,500 m a.s.l., in close proximity to a highly frequented hiking trail. On an area of 0.2 ha, three several meter deep cracks were identified. Here we present the results of a 3-year monitoring of this area with low-cost, unmanned aerial systems (UAS) and photogrammetric techniques. In 2013 and 2014, a custom-built fixed-wing UAS (Multiplex Mentor, wingspan 1.6 m, gross take-off weight 2.5 kg), equipped with a Sony NEX5 (16 mm prime lens, 14 MP sensor resolution) was used to map the study site. In 2015 we employed a helicopter (Thundertiger Raptor, 0.55 m blade length, gross take-off weight 2.8 kg), fitted with a GoPro2 (60° prime lens, 5 MP sensor resolution). In all three cases we recorded 1,200-2,000 images in 10-30 minutes. To georeference the images, 8-10 ground control points (GCP) were placed at the study site and measured with a Trimble GeoXT GPS device (expected accuracy 0.15 m, precision 0.3 m). Using AgiSoft's PhotoScan (v.1.1.6), Orthophotos (OP) and digital surface models (DSM) were calculated with 5 and 20 cm ground sampling distance, respectively. The visual interpretation of the OPs gave some indication, that the size of the cracks was increasing by 0.1-0.5 m (A-axis) or 0.2-0.8 m² per year. An interpretation of the DSMs was inconclusive with regard to the depth of the cracks due to shadows in the imagery and vertical or overhanging sidewalls of the cracks. Additionally the accuracy of the GCP-measurements was found to lie below the rate of change of the cracks, thus not permitting a direct calculation of difference DSM. From an operational point-of-view, the study site proved very challenging because of its exposed, high-alpine location, with high wind speeds, gusts and poor visibility hampering the UAS-missions. The monitoring campaign will continue in 2016, where the collection of additional ground-based reference data is planned (e.g. terrestrial

  12. Study on High Accuracy Topographic Mapping via UAV-based Images

    Science.gov (United States)

    Chi, Yun-Yao; Lee, Ya-Fen; Tsai, Shang-En

    2016-10-01

    Unmanned aerial vehicle (UAV) provides a promising tool for the acquisition of such multi-temporal aerial stereo photos and high-resolution digital surface models. Recently, the flight of UAVs operates with high degrees of autonomy by the global position system and onboard digit camera and computer. The UAV-based mapping can be obtained faster and cheaper, but its accuracy is anxious. This paper aims to identify the integration ability of high accuracy topographic map via the image of quad-rotors UAV and ground control points (GCPs). The living survey data is collected in the Errn river basins area in Tainan, Taiwan. The high accuracy UAV-based topographic in the study area is calibrated by the local coordinate of GCPs using the total station with the accuracy less than 1/2000. The comparison results show the accuracy of UAV-based topographic is accepted by overlapping. The results can be a reference for the practice works of mapping survey in earth.

  13. Examining Urban Expansion Using Multi-Temporal Landsat Imagery: a Case Study of the Montreal Census Metropolitan Area from 1975 TO 2015, Canada

    Science.gov (United States)

    Ma, Lingfei; Zhao, He; Li, Jonathan

    2016-06-01

    Urban expansion, particularly the movement of residential and commercial land use to sub-urban areas in metropolitan areas, has been considered as a significant signal of regional economic development. In 1970s, the economic centre of Canada moved from Montreal to Toronto. Since some previous research have been focused on the urbanization process in Greater Toronto Area (GTA), it is significant to conduct research in its counterpart. This study evaluates urban expansion process in Montréal census metropolitan area (CMA), Canada, between 1975 and 2015 using satellite images and socio-economic data. Spatial and temporal dynamic information of urbanization process was quantified using Landsat imagery, supervised classification algorithms and the post-classification change detection technique. Accuracy of the Landsat-derived land use classification map ranged from 80% to 97%. The results indicated that continuous growth of built-up areas in the CMA over the study period resulted in a decrease in the area of cultivated land and vegetation. The results showed that urban areas expanded 442 km2 both along major river systems and lakeshores, as well as expanded from urban centres to surrounded areas. The analysis revealed that urban expansion has been largely driven by population growth and economic development. Consequently, the urban expansion maps produced in this research can assist decision-makers to promote sustainable urban development, and forecast potential changes in urbanization growth patterns.

  14. Detection of Land Use/Land Cover Changes and Urban Sprawl in Al-Khobar, Saudi Arabia: An Analysis of Multi-Temporal Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Muhammad Tauhidur Rahman

    2016-02-01

    Full Text Available While several studies examined land use and land cover changes in the central and western parts of Saudi Arabia, this study is the first to use remote sensing data to examine the decadal land cover changes in Saudi Arabia’s eastern coastal city of Al-Khobar between 1990 and 2013. Specifically, it utilized ISODATA classification method to classify Landsat TM, ETM+, and OLI data collected from 1990, 2001, and 2013 and then detected changes in the land cover within the study area. It then measured urban sprawl by calculating the relative Shannon’s entropy index values for the three years. With overall classification accuracies greater than 85%, the results show that urban built-up areas increased by 117% between 1990 and 2001 and 43.51% from 2001 to 2013. Vegetation increased by 110% from 1990 to 2001 and by 52% between 2001 and 2013. The entropy index values of 0.700 (1990, 0.779 (2001, and 0.840 (2013 indicates a high rate of urban sprawl and the city dispersing near the outskirts and towards the neighboring cities of Dhahran and Dammam. Future studies should examine the current challenges faced by the city’s residents due to urban expansion and attempt to find ways to resolve them in the near future.

  15. Accuracy Assessment Points for Badlands National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the accuracy assessment data associated with the vegetation land cover and land use geospatial database for Badlands National Park and...

  16. Estimation of Paddy Rice Variables with a Modified Water Cloud Model and Improved Polarimetric Decomposition Using Multi-Temporal RADARSAT-2 Images

    Directory of Open Access Journals (Sweden)

    Zhi Yang

    2016-10-01

    Full Text Available Rice growth monitoring is very important as rice is one of the staple crops of the world. Rice variables as quantitative indicators of rice growth are critical for farming management and yield estimation, and synthetic aperture radar (SAR has great advantages for monitoring rice variables due to its all-weather observation capability. In this study, eight temporal RADARSAT-2 full-polarimetric SAR images were acquired during rice growth cycle and a modified water cloud model (MWCM was proposed, in which the heterogeneity of the rice canopy in the horizontal direction and its phenological changes were considered when the double-bounce scattering between the rice canopy and the underlying surface was firstly considered as well. Then, three scattering components from an improved polarimetric decomposition were coupled with the MWCM, instead of the backscattering coefficients. Using a genetic algorithm, eight rice variables were estimated, such as the leaf area index (LAI, rice height (h, and the fresh and dry biomass of ears (Fe and De. The accuracy validation showed the MWCM was suitable for the estimation of rice variables during the whole growth season. The validation results showed that the MWCM could predict the temporal behaviors of the rice variables well during the growth cycle (R2 > 0.8. Compared with the original water cloud model (WCM, the relative errors of rice variables with the MWCM were much smaller, especially in the vegetation phase (approximately 15% smaller. Finally, it was discussed that the MWCM could be used, theoretically, for extensive applications since the empirical coefficients in the MWCM were determined in general cases, but more applications of the MWCM are necessary in future work.

  17. Use of Aerial high resolution visible imagery to produce large river bathymetry: a multi temporal and spatial study over the by-passed Upper Rhine

    Science.gov (United States)

    Béal, D.; Piégay, H.; Arnaud, F.; Rollet, A.; Schmitt, L.

    2011-12-01

    Aerial high resolution visible imagery allows producing large river bathymetry assuming that water depth is related to water colour (Beer-Bouguer-Lambert law). In this paper we aim at monitoring Rhine River geometry changes for a diachronic study as well as sediment transport after an artificial injection (25.000 m3 restoration operation). For that a consequent data base of ground measurements of river depth is used, built on 3 different sources: (i) differential GPS acquisitions, (ii) sounder data and (iii) lateral profiles realized by experts. Water depth is estimated using a multi linear regression over neo channels built on a principal component analysis over red, green and blue bands and previously cited depth data. The study site is a 12 km long reach of the by-passed section of the Rhine River that draws French and German border. This section has been heavily impacted by engineering works during the last two centuries: channelization since 1842 for navigation purposes and the construction of a 45 km long lateral canal and 4 consecutive hydroelectric power plants of since 1932. Several bathymetric models are produced based on 3 different spatial resolutions (6, 13 and 20 cm) and 5 acquisitions (January, March, April, August and October) since 2008. Objectives are to find the optimal spatial resolution and to characterize seasonal effects. Best performances according to the 13 cm resolution show a 18 cm accuracy when suspended matters impacted less water transparency. Discussions are oriented to the monitoring of the artificial reload after 2 flood events during winter 2010-2011. Bathymetric models produced are also useful to build 2D hydraulic model's mesh.

  18. A spatial-temporal Hopfield neural network approach for super-resolution land cover mapping with multi-temporal different resolution remotely sensed images

    Science.gov (United States)

    Li, Xiaodong; Ling, Feng; Du, Yun; Feng, Qi; Zhang, Yihang

    2014-07-01

    The mixed pixel problem affects the extraction of land cover information from remotely sensed images. Super-resolution mapping (SRM) can produce land cover maps with a finer spatial resolution than the remotely sensed images, and reduce the mixed pixel problem to some extent. Traditional SRMs solely adopt a single coarse-resolution image as input. Uncertainty always exists in resultant fine-resolution land cover maps, due to the lack of information about detailed land cover spatial patterns. The development of remote sensing technology has enabled the storage of a great amount of fine spatial resolution remotely sensed images. These data can provide fine-resolution land cover spatial information and are promising in reducing the SRM uncertainty. This paper presents a spatial-temporal Hopfield neural network (STHNN) based SRM, by employing both a current coarse-resolution image and a previous fine-resolution land cover map as input. STHNN considers the spatial information, as well as the temporal information of sub-pixel pairs by distinguishing the unchanged, decreased and increased land cover fractions in each coarse-resolution pixel, and uses different rules in labeling these sub-pixels. The proposed STHNN method was tested using synthetic images with different class fraction errors and real Landsat images, by comparing with pixel-based classification method and several popular SRM methods including pixel-swapping algorithm, Hopfield neural network based method and sub-pixel land cover change mapping method. Results show that STHNN outperforms pixel-based classification method, pixel-swapping algorithm and Hopfield neural network based model in most cases. The weight parameters of different STHNN spatial constraints, temporal constraints and fraction constraint have important functions in the STHNN performance. The heterogeneity degree of the previous map and the fraction images errors affect the STHNN accuracy, and can be served as guidances of selecting the

  19. Kaloko-Honokohau National Historical Park Vegetation Mapping Project - Field Plots, Observation and Accuracy Assessment Points

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 vegetation (classification) field plots (spatial database) and 2010 accuracy assessment points (spatial database) created from the...

  20. Data from clinical database on septic shock are valid

    DEFF Research Database (Denmark)

    Grønlykke, Lars; Brandstrup, Sofie Louise Rygaard; Perner, Anders

    2012-01-01

    Clinical databases have become important tools in intensive care. Disease severity and organ dysfunction scoring systems are registered in the databases, including the Simplified Acute Physiology Score II (SAPS II) and the Sequential Organ Failure Assessment (SOFA) score. The purpose of this study...... was to evaluate the reliability and accuracy of a clinical database on intensive care unit (ICU) patients....

  1. Multi-temporal Reconstruction of a 35km reach of the Dart River Valley, New Zealand with the Structure-from-Motion pipeline (SfM).

    Science.gov (United States)

    James, Joe; Brasington, James; Cook, Simon; Cox, Simon; Lotsari, Eliisa; McColl, Sam; Lehane, Niall; Williams, Richard; Vericat, Damia

    2016-04-01

    Two discrete surveys, May 2014 and May 2015, were undertaken to capture the topography of a 35km reach of the Dart River, immediately downstream of a significant landslide that initially dammed the river in January 2014. Repeat surveys provide the opportunity to broadly quantify morphological response in terms of elevation change through Dem-of-Differencing. Such an approach requires the generation of consistent surfaces devoid of systematic bias across each epoch that are accurately geo-referenced and of a research specific, minimum accuracy. For this study, the highly automated cost effective method of SfM has been used to generate catchment models at a x, y resolution of 0.5m. This was achieved through the helicopter mounted capture of ~2,000 nadir only images, using a Nikon D90 (2014) and ~10,000 convergent images using two Nikon D750'S (2015) at a height of 350m above ground at a flight speed of 85 knots. Both surveys were geo-referenced by 100 Ground Control Points (GCP) measured with Real-Time-Kinetic (RTK) GPS, with additional control in the form of a series of TLS scans across the length of the catchment. Initial results from 2014 show prevalent systematic errors from both inadequate camera network geometry and ground control. The following survey from 2015 makes use of a convergent network with increased ground control to theoretically provide catchment topography with minimal bias. In the absence of a convergent network, results from 2014 may be improved via additional ground control to extend the 3-dimensional radius of control, beyond which, results are often inferred. In this instance the 2015 data set has been used to provide additional reference through the identification of concurrent features which are unlikely to have moved between surveys, such as town buildings. The final reconstructions from both 2014 and 2015 are sufficiently accurate to provide us with the opportunity to perform detailed analysis to answer a range of geomorphological

  2. Database development and management

    CERN Document Server

    Chao, Lee

    2006-01-01

    Introduction to Database Systems Functions of a DatabaseDatabase Management SystemDatabase ComponentsDatabase Development ProcessConceptual Design and Data Modeling Introduction to Database Design Process Understanding Business ProcessEntity-Relationship Data Model Representing Business Process with Entity-RelationshipModelTable Structure and NormalizationIntroduction to TablesTable NormalizationTransforming Data Models to Relational Databases .DBMS Selection Transforming Data Models to Relational DatabasesEnforcing ConstraintsCreating Database for Business ProcessPhysical Design and Database

  3. Target Price Accuracy

    Directory of Open Access Journals (Sweden)

    Alexander G. Kerl

    2011-04-01

    Full Text Available This study analyzes the accuracy of forecasted target prices within analysts’ reports. We compute a measure for target price forecast accuracy that evaluates the ability of analysts to exactly forecast the ex-ante (unknown 12-month stock price. Furthermore, we determine factors that explain this accuracy. Target price accuracy is negatively related to analyst-specific optimism and stock-specific risk (measured by volatility and price-to-book ratio. However, target price accuracy is positively related to the level of detail of each report, company size and the reputation of the investment bank. The potential conflicts of interests between an analyst and a covered company do not bias forecast accuracy.

  4. Rethinking Empathic Accuracy

    OpenAIRE

    Meadors, Joshua

    2014-01-01

    The present study is a methodological examination of the implicit empathic accuracy measure introduced by Zaki, Ochsner, and Bolger (2008). Empathic accuracy (EA) is defined as the ability to understand another person's thoughts and feelings (Ickes, 1993). Because this definition is similar to definitions of cognitive empathy (e.g., Shamay-Tsoory, 2011) and because affective empathy does not appear to be related to empathic accuracy (Zaki et al., 2008), the Basic Empathy Scale--which measures...

  5. Global Terrestrial Network for Glaciers: Databases and Web interfaces

    Science.gov (United States)

    Raup, B.; Armstrong, R.; Fetterer, F.; Gartner-Roer, I.; Haeberli, W.; Hoelzle, M.; Khalsa, S. J. S.; Nussbaumer, S.; Weaver, R.; Zemp, M.

    2012-04-01

    The Global Terrestrial Network for Glaciers (GTN-G) is an umbrella organization with links to the Global Climate Observing System (GCOS), Global Terrestrial Observing System (GTOS), and UNESCO (all organizations under the United Nations), for the curation of several glacier-related databases. It is composed of the World Glacier Monitoring Service (WGMS), the U.S. National Snow and Ice Data Center (NSIDC), and the Global Land Ice Measurements from Space (GLIMS) initiative. The glacier databases include the World Glacier Inventory (WGI), the GLIMS Glacier Database, the Glacier Photograph Collection at NSIDC, and the Fluctuations of Glaciers (FoG) and Mass Balance databases at WGMS. We are working toward increased interoperability between these related databases. For example, the Web interface to the GLIMS Glacier Database has also included queryable layers for the WGI and FoG databases since 2008. To improve this further, we have produced a new GTN-G web portal (http://www.gtn-g.org/), which includes a glacier metadata browsing application. This web application allows the browsing of the metadata behind the main GTN-G databases, as well as querying the metadata in order to get to the source, no matter which database holds the data in question. A new glacier inventory, called the Randolph Glacier Inventory 1.0, has recently been compiled. This compilation, which includes glacier outlines that do not have the attributes or IDs or links to other data like the GLIMS data do, was motivated by the tight deadline schedule of the sea level chapter of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Now served from the GLIMS website (http://glims.org/), it is designed to serve that narrowly focused research goal in the near term, and in the longer term will be incorporated into the multi-temporal glacier database of GLIMS. For the required merging of large sets of glacier outlines and association of proper IDs that tie together outlines

  6. Improving Estimation Accuracy of Aggregate Queries on Data Cubes

    Energy Technology Data Exchange (ETDEWEB)

    Pourabbas, Elaheh; Shoshani, Arie

    2008-08-15

    In this paper, we investigate the problem of estimation of a target database from summary databases derived from a base data cube. We show that such estimates can be derived by choosing a primary database which uses a proxy database to estimate the results. This technique is common in statistics, but an important issue we are addressing is the accuracy of these estimates. Specifically, given multiple primary and multiple proxy databases, that share the same summary measure, the problem is how to select the primary and proxy databases that will generate the most accurate target database estimation possible. We propose an algorithmic approach for determining the steps to select or compute the source databases from multiple summary databases, which makes use of the principles of information entropy. We show that the source databases with the largest number of cells in common provide the more accurate estimates. We prove that this is consistent with maximizing the entropy. We provide some experimental results on the accuracy of the target database estimation in order to verify our results.

  7. Databases and their application

    NARCIS (Netherlands)

    E.C. Grimm; R.H.W Bradshaw; S. Brewer; S. Flantua; T. Giesecke; A.M. Lézine; H. Takahara; J.W.,Jr Williams

    2013-01-01

    During the past 20 years, several pollen database cooperatives have been established. These databases are now constituent databases of the Neotoma Paleoecology Database, a public domain, multiproxy, relational database designed for Quaternary-Pliocene fossil data and modern surface samples. The poll

  8. [Total quality management of clinical database].

    Science.gov (United States)

    Okubo, Suguru; Miyata, Hiroaki; Tomotaki, Ai; Motomura, Noboru; Murakami, Arata; Ono, Minoru; Iwanaka, Tadashi

    2013-06-01

    Data entry system should be constructed considering utility, accuracy, propriety, and feasibility. The methods for developing useful and accurate clinical databases are 1)system development based on the concept of "error proofing", 2)system test by real users, 3)guidances for participants, and 4)incentive for accurate data entry. In terms of propriety, to gain patient's consent on data collection and to publicly announce objectives and methods of clinical database are necessary. Confidentiality and anonymization of data are also important. Balancing efficacy and propriety for maximization of patients' and societal benefit is one of the important responsibilities of database management organizations. In addition, assessment of data quality such as audit and feedback is useful for enhancing accuracy and reliability of clinical databases.

  9. The impact of database quality on keystroke dynamics authentication

    KAUST Repository

    Panasiuk, Piotr

    2016-06-11

    This paper concerns keystroke dynamics, also partially in the context of touchscreen devices. The authors concentrate on the impact of database quality and propose their algorithm to test database quality issues. The algorithm is used on their own database> as well as the well-known database>. Following specific problems were researched: classification accuracy, development of user typing proficiency, time precision during sample acquisition, representativeness of training set, sample length.

  10. Dietary Supplement Ingredient Database

    Science.gov (United States)

    ... and US Department of Agriculture Dietary Supplement Ingredient Database Toggle navigation Menu Home About DSID Mission Current ... values can be saved to build a small database or add to an existing database for national, ...

  11. NoSQL Databases

    OpenAIRE

    2013-01-01

    This thesis deals with database systems referred to as NoSQL databases. In the second chapter, I explain basic terms and the theory of database systems. A short explanation is dedicated to database systems based on the relational data model and the SQL standardized query language. Chapter Three explains the concept and history of the NoSQL databases, and also presents database models, major features and the use of NoSQL databases in comparison with traditional database systems. In the fourth ...

  12. USAID Anticorruption Projects Database

    Data.gov (United States)

    US Agency for International Development — The Anticorruption Projects Database (Database) includes information about USAID projects with anticorruption interventions implemented worldwide between 2007 and...

  13. Collecting Taxes Database

    Data.gov (United States)

    US Agency for International Development — The Collecting Taxes Database contains performance and structural indicators about national tax systems. The database contains quantitative revenue performance...

  14. Accuracy of Sphygmomanometers

    OpenAIRE

    Basak, Okay

    2014-01-01

    One of the factors affecting the accuracy of readings of blood pressure is the equipment used. Defects or inaccuracy of aneroid sphygmomanometers may be source of error in blood pressure measurement. We inspected 100 sphygmomanometers for physical defects and assessed their accuracy against a standard mercury manometer at four different pressure points. 46 of the 100 sphygmomanometers were determined to be intolerant (deviation from the mercury manometer by greater than±3 mm Hg at two or more...

  15. Exploiting COSMO-Skymed Data and Multi-Temporal Interferometry for Early Detection of Landslide Hazard: A Case of Slope Failure and Train Derailment Near Marina Di Andora, Italy.

    Science.gov (United States)

    Wasowski, J.; Chiaradia, M.; Bovenga, F.; Nutricato, R.; Nitti, D. O.; Milillo, G.; Guerriero, L.

    2014-12-01

    The improving temporal and spatial resolutions of new generation space-borne X-Band SAR sensors such as COSMO-SkyMed (CSK) constellation, and therefore their better monitoring capabilities, will guarantee increasing and more efficient use of multi-temporal interferometry (MTI) in landslide investigations. Thanks to their finer spatial resolution with respect to C-band data, X-band InSAR applications are very promising also for monitoring smaller landslides and single engineering structures sited on potentially unstable slopes. This work is focused on the detection of precursory signals of an impending slope failure from MTI time series of ground deformations obtained by exploiting 3 m resolution CSK data. We show the case of retrospectively captured pre-failure strains related to the landslide which occurred on January 2014 close to the town of Marina di Andora. The landslide caused the derailment of a train and the interruption of the railway line connecting north-western Italy to France. A dataset of 56 images acquired in STRIPMAP HIMAGE mode by CSK constellation from October 2008 to May 2014 was processed through SPINUA algorithm to derive the ground surface deformation map and the time series of displacement rates for each coherent radar target. We show that a cluster of moving targets coincides with the structures (buildings and terraces) affected by the 2014 landslide. The analysis of the MTI time series further shows that the targets had been moving since 2009, and thus could have provided a forewarning signal about ongoing slope or engineering structure instability. Although temporal landslide prediction remains difficult even via in situ monitoring, the presented case study indicates that MTI relying on high resolution radars such as CSK can provide very useful information for slope hazard mapping and possibly for early warning. Acknowledgments DIF provided contribution to data analysis within the framework of CAR-SLIDE project funded by MIUR (PON01_00536).

  16. Application of Multi-temporal Statistical Data Dynamic Spatial Visualization Methods%多时相统计数据空间动态可视化模型研究

    Institute of Scientific and Technical Information of China (English)

    周平; 唐新明; 张过

    2012-01-01

    By describing the spatial-temporal characteristics of statistical data and extending the dynamic visual parameters of dynamic spatial visualization,three types of dynamic statistical charts are designed.Those charts are based on dynamic spatial visualization of electronic map and are used in representing the multi-temporal statistical information.According to time factor technology using in map animation and the interpolation technology using in the key-frame,the idea and the flow of dynamic statistical charts are designed and built.Meanwhile,the research results was adopted in a program,which realized the visualization expression of the statistical data which is changing as time.Finally,we achieved the expected effect of dynamic spatial visualization expression of statistical data,which indicating that the research has certain promotion value.%阐述了统计数据的时空特性,扩展了动态空间可视化的动态视觉参量,设计了3种用于多时相统计信息动态空间可视化的"动态统计图表"。采用时间地图动画技术及关键帧插值动画技术来设计与构建动态统计图表,并将此方法应用于相应系统,实现了统计数据随时间变化动态特性的可视化表达。

  17. Characterizing the primary material sources and dominant erosional processes for post-fire debris-flow initiation in a headwater basin using multi-temporal terrestrial laser scanning data

    Science.gov (United States)

    Staley, Dennis M.; Waslewicz, Thad A.; Kean, Jason W.

    2014-01-01

    Wildfire dramatically alters the hydrologic response of a watershed such that even modest rainstorms can produce hazardous debris flows. Relative to shallow landslides, the primary sources of material and dominant erosional processes that contribute to post-fire debris-flow initiation are poorly constrained. Improving our understanding of how and where material is eroded from a watershed during a post-fire debris-flow requires (1) precise measurements of topographic change to calculate volumetric measurements of erosion and deposition, and (2) the identification of relevant morphometrically defined process domains to spatially constrain these measurements of erosion and deposition. In this study, we combine the morphometric analysis of a steep, small (0.01 km2) headwater drainage basin with measurements of topographic change using high-resolution (2.5 cm) multi-temporal terrestrial laser scanning data made before and after a post-fire debris flow. The results of the morphometric analysis are used to define four process domains: hillslope-divergent, hillslope-convergent, transitional, and channelized incision. We determine that hillslope-divergent and hillslope-convergent process domains represent the primary sources of material over the period of analysis in the study basin. From these results we conclude that raindrop-impact induced erosion, ravel, surface wash, and rilling are the primary erosional processes contributing to post-fire debris-flow initiation in the small, steep headwater basin. Further work is needed to determine (1) how these results vary with increasing drainage basin size, (2) how these data might scale upward for use with coarser resolution measurements of topography, and (3) how these results change with evolving sediment supply conditions and vegetation recovery.

  18. Characterizing the primary material sources and dominant erosional processes for post-fire debris-flow initiation in a headwater basin using multi-temporal terrestrial laser scanning data

    Science.gov (United States)

    Staley, Dennis M.; Wasklewicz, Thad A.; Kean, Jason W.

    2014-06-01

    Wildfire dramatically alters the hydrologic response of a watershed such that even modest rainstorms can produce hazardous debris flows. Relative to shallow landslides, the primary sources of material and dominant erosional processes that contribute to post-fire debris-flow initiation are poorly constrained. Improving our understanding of how and where material is eroded from a watershed during a post-fire debris-flow requires (1) precise measurements of topographic change to calculate volumetric measurements of erosion and deposition, and (2) the identification of relevant morphometrically defined process domains to spatially constrain these measurements of erosion and deposition. In this study, we combine the morphometric analysis of a steep, small (0.01 km2) headwater drainage basin with measurements of topographic change using high-resolution (2.5 cm) multi-temporal terrestrial laser scanning data made before and after a post-fire debris flow. The results of the morphometric analysis are used to define four process domains: hillslope-divergent, hillslope-convergent, transitional, and channelized incision. We determine that hillslope-divergent and hillslope-convergent process domains represent the primary sources of material over the period of analysis in the study basin. From these results we conclude that raindrop-impact induced erosion, ravel, surface wash, and rilling are the primary erosional processes contributing to post-fire debris-flow initiation in the small, steep headwater basin. Further work is needed to determine (1) how these results vary with increasing drainage basin size, (2) how these data might scale upward for use with coarser resolution measurements of topography, and (3) how these results change with evolving sediment supply conditions and vegetation recovery.

  19. Soil moisture retrieval using multi-temporal Sentinel-1 SAR data in agricultural areas%利用多时相Sentinel-1 SAR数据反演农田地表土壤水分

    Institute of Scientific and Technical Information of China (English)

    何连; 秦其明; 任华忠; 都骏; 孟晋杰; 杜宸

    2016-01-01

    土壤水分是陆面生态系统水分和能量循环的重要变量,在农田干旱监测、作物长势监测和作物估产等应用研究中具有重要的作用。该文结合基于变化检测的Alpha近似模型,利用Sentinel-1卫星获取的多时相C波段合成孔径雷达(synthetic aperture radar,SAR)数据,实现了农田地表土壤水分的反演。该文首先利用微波辐射传输模型验证了Alpha近似模型在土壤水分反演中的合理性。研究发现,对于土壤散射占主导的区域,Alpha近似模型对辐射传输模型有较好的近似,能够有效地消除地表粗糙度和植被对雷达后向散射系数的影响。在此基础上,结合怀来研究区多时相Sentinel-1 SAR数据,利用Alpha近似模型构建了土壤水分观测方程组,通过求解方程组得到了农田地表土壤水分。地面验证结果表明,土壤水分反演的均方根误差(root mean square error,RMSE)为0.06 cm3/cm3,平均偏差为0.01 cm3/cm3,精度较好。该文研究为利用高重访周期、多时相的Sentinel-1 SAR数据获取农田地表土壤水分提供了参考。%Soil moisture is a key variable that links the water and energy cycles. Its information is also essential for many applications, such as agricultural drought monitoring, crop status monitoring and crop yield prediction. Sentinel-1 of the European Space Agency (ESA) is composed of 2 satellites, Sentinel-1A and Sentinel-1B, which share the same orbital plane with a 180° orbital phasing difference. The Sentinel-1 mission can provide C-band synthetic aperture radar (SAR) data with a global revisit time of just 6 days and high spatial resolution of about tens of meters, thus showing a strong potential for global soil moisture monitoring at high/moderate spatial resolutions. The aim of this study was to investigate the capability of multi-temporal Sentinel-1 C-band SAR data with a short repeating cycle in soil moisture estimation over

  20. Cloud Databases: A Paradigm Shift in Databases

    Directory of Open Access Journals (Sweden)

    Indu Arora

    2012-07-01

    Full Text Available Relational databases ruled the Information Technology (IT industry for almost 40 years. But last few years have seen sea changes in the way IT is being used and viewed. Stand alone applications have been replaced with web-based applications, dedicated servers with multiple distributed servers and dedicated storage with network storage. Cloud computing has become a reality due to its lesser cost, scalability and pay-as-you-go model. It is one of the biggest changes in IT after the rise of World Wide Web. Cloud databases such as Big Table, Sherpa and SimpleDB are becoming popular. They address the limitations of existing relational databases related to scalability, ease of use and dynamic provisioning. Cloud databases are mainly used for data-intensive applications such as data warehousing, data mining and business intelligence. These applications are read-intensive, scalable and elastic in nature. Transactional data management applications such as banking, airline reservation, online e-commerce and supply chain management applications are write-intensive. Databases supporting such applications require ACID (Atomicity, Consistency, Isolation and Durability properties, but these databases are difficult to deploy in the cloud. The goal of this paper is to review the state of the art in the cloud databases and various architectures. It further assesses the challenges to develop cloud databases that meet the user requirements and discusses popularly used Cloud databases.

  1. Logical database design principles

    CERN Document Server

    Garmany, John; Clark, Terry

    2005-01-01

    INTRODUCTION TO LOGICAL DATABASE DESIGNUnderstanding a Database Database Architectures Relational Databases Creating the Database System Development Life Cycle (SDLC)Systems Planning: Assessment and Feasibility System Analysis: RequirementsSystem Analysis: Requirements Checklist Models Tracking and Schedules Design Modeling Functional Decomposition DiagramData Flow Diagrams Data Dictionary Logical Structures and Decision Trees System Design: LogicalSYSTEM DESIGN AND IMPLEMENTATION The ER ApproachEntities and Entity Types Attribute Domains AttributesSet-Valued AttributesWeak Entities Constraint

  2. An Interoperable Cartographic Database

    OpenAIRE

    Slobodanka Ključanin; Zdravko Galić

    2007-01-01

    The concept of producing a prototype of interoperable cartographic database is explored in this paper, including the possibilities of integration of different geospatial data into the database management system and their visualization on the Internet. The implementation includes vectorization of the concept of a single map page, creation of the cartographic database in an object-relation database, spatial analysis, definition and visualization of the database content in the form of a map on t...

  3. Evaluating Measurement Accuracy

    CERN Document Server

    Rabinovich, Semyon G

    2010-01-01

    The goal of Evaluating Measurement Accuracy: A Practical Approach is to present methods for estimating the accuracy of measurements performed in industry, trade, and scientific research. Although multiple measurements are the focus of current theory, single measurements are the ones most commonly used. This book answers fundamental questions not addressed by present theory, such as how to discover the complete uncertainty of a measurement result. In developing a general theory of processing experimental data, this book, for the first time, presents the postulates of the theory of measurements. It introduces several new terms and definitions about the relationship between the accuracy of measuring instruments and measurements utilizing these instruments. It also offers well-grounded and practical methods for combining the components of measurement inaccuracy. From developing the theory of indirect measurements to proposing new methods of reduction in place of the traditional ones, this work encompasses the ful...

  4. The Truth about Accuracy

    NARCIS (Netherlands)

    Buekens, F.A.I.; Truyen, Frederick; Martini, Carlo; Boumans, Marcel

    2014-01-01

    When we evaluate the outcomes of investigative actions as justified or unjustified, good or bad, rational or irrational, we make, in a broad sense of the term, evaluative judgements about them. We look at operational accuracy as a desirable and evaluable quality of the outcomes and explore how the c

  5. Database Description - RMOS | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us RMOS Database Description General information of database Database name RMOS Alternative nam...arch Unit Shoshi Kikuchi E-mail : Database classification Plant databases - Rice Microarray Data and other Gene Expression Database...s Organism Taxonomy Name: Oryza sativa Taxonomy ID: 4530 Database description The Ric...e Microarray Opening Site is a database of comprehensive information for Rice Mic...es and manner of utilization of database You can refer to the information of the

  6. Pu`ukohola Heiau National Historic Site Vegetation Mapping Project - Field Plots, Observation and Accuracy Assessment Points

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 vegetation (classification) field plots (spatial database) and 2010 accuracy assessment points (spatial database) created from the...

  7. E3 Staff Database

    Data.gov (United States)

    US Agency for International Development — E3 Staff database is maintained by E3 PDMS (Professional Development & Management Services) office. The database is Mysql. It is manually updated by E3 staff as...

  8. Native Health Research Database

    Science.gov (United States)

    ... APP WITH JAVASCRIPT TURNED OFF. THE NATIVE HEALTH DATABASE REQUIRES JAVASCRIPT IN ORDER TO FUNCTION. PLEASE ENTER ... To learn more about searching the Native Health Database, click here. Keywords Title Author Source of Publication ...

  9. Physiological Information Database (PID)

    Science.gov (United States)

    EPA has developed a physiological information database (created using Microsoft ACCESS) intended to be used in PBPK modeling. The database contains physiological parameter values for humans from early childhood through senescence as well as similar data for laboratory animal spec...

  10. Cell Centred Database (CCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Cell Centered Database (CCDB) is a web accessible database for high resolution 2D, 3D and 4D data from light and electron microscopy, including correlated imaging.

  11. Database Urban Europe

    NARCIS (Netherlands)

    Sleutjes, B.; de Valk, H.A.G.

    2016-01-01

    Database Urban Europe: ResSegr database on segregation in The Netherlands. Collaborative research on residential segregation in Europe 2014–2016 funded by JPI Urban Europe (Joint Programming Initiative Urban Europe).

  12. Property Modelling and Databases in Product-Process Design

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Sansonetti, Sascha

    of the PC-SAFT is used. The developed database and property prediction models have been combined into a properties-software that allows different product-process design related applications. The presentation will also briefly highlight applications of the software for virtual product-process design...... development, however, it is necessary to have a large database of measured property data that has been checked for consistency and accuracy. The presentation will first introduce a database, in terms of its knowledge representation structure, the type and range of properties and chemical systems covered......, and their internal consistency-accuracy checks. The database includes properties of organic chemicals, polymers and ionic liquids. There are also chemical class specific database sections, such as for solvents, aroma-chemicals, surfactants and emulsifiers. The use of this property database for model development...

  13. Property Modelling and Databases in Product-Process Design

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Sansonetti, Sascha

    development, however, it is necessary to have a large database of measured property data that has been checked for consistency and accuracy. The presentation will first introduce a database, in terms of its knowledge representation structure, the type and range of properties and chemical systems covered......, and their internal consistency-accuracy checks. The database includes properties of organic chemicals, polymers and ionic liquids. There are also chemical class specific database sections, such as for solvents, aroma-chemicals, surfactants and emulsifiers. The use of this property database for model development...... of the PC-SAFT is used. The developed database and property prediction models have been combined into a properties-software that allows different product-process design related applications. The presentation will also briefly highlight applications of the software for virtual product-process design...

  14. Scopus database: a review.

    Science.gov (United States)

    Burnham, Judy F

    2006-03-08

    The Scopus database provides access to STM journal articles and the references included in those articles, allowing the searcher to search both forward and backward in time. The database can be used for collection development as well as for research. This review provides information on the key points of the database and compares it to Web of Science. Neither database is inclusive, but complements each other. If a library can only afford one, choice must be based in institutional needs.

  15. Future database machine architectures

    OpenAIRE

    Hsiao, David K.

    1984-01-01

    There are many software database management systems available on many general-purpose computers ranging from micros to super-mainframes. Database machines as backened computers can offload the database management work from the mainframe so that we can retain the same mainframe longer. However, the database backend must also demonstrate lower cost, higher performance, and newer functionality. Some of the fundamental architecture issues in the design of high-performance and great-capacity datab...

  16. MPlus Database system

    Energy Technology Data Exchange (ETDEWEB)

    1989-01-20

    The MPlus Database program was developed to keep track of mail received. This system was developed by TRESP for the Department of Energy/Oak Ridge Operations. The MPlus Database program is a PC application, written in dBase III+'' and compiled with Clipper'' into an executable file. The files you need to run the MPLus Database program can be installed on a Bernoulli, or a hard drive. This paper discusses the use of this database.

  17. Reconceptualizing metacomprehension calibration accuracy

    OpenAIRE

    Egan, Rylan Graham

    2012-01-01

    Accurate judgment of text comprehension is compulsory for learners to effectively self-regulate learning from text. Unfortunately, until relatively recently the literature on text comprehension judgment, termed metacomprehension, has shown learners to be inaccurate in their judgments. Over the last decade researchers have discovered that when learners use delayed summaries of text to make judgments metacomprehension accuracy increases. In contrast, when learners use individual differences (e....

  18. Geoid undulation accuracy

    Science.gov (United States)

    Rapp, Richard H.

    1993-01-01

    The determination of the geoid and equipotential surface of the Earth's gravity field, has long been of interest to geodesists and oceanographers. The geoid provides a surface to which the actual ocean surface can be compared with the differences implying information on the circulation patterns of the oceans. For use in oceanographic applications the geoid is ideally needed to a high accuracy and to a high resolution. There are applications that require geoid undulation information to an accuracy of +/- 10 cm with a resolution of 50 km. We are far from this goal today but substantial improvement in geoid determination has been made. In 1979 the cumulative geoid undulation error to spherical harmonic degree 20 was +/- 1.4 m for the GEM10 potential coefficient model. Today the corresponding value has been reduced to +/- 25 cm for GEM-T3 or +/- 11 cm for the OSU91A model. Similar improvements are noted by harmonic degree (wave-length) and in resolution. Potential coefficient models now exist to degree 360 based on a combination of data types. This paper discusses the accuracy changes that have taken place in the past 12 years in the determination of geoid undulations.

  19. CTD_DATABASE - Cascadia tsunami deposit database

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Cascadia Tsunami Deposit Database contains data on the location and sedimentological properties of tsunami deposits found along the Cascadia margin. Data have...

  20. The impact of database quality on keystroke dynamics authentication

    Science.gov (United States)

    Panasiuk, Piotr; Rybnik, Mariusz; Saeed, Khalid; Rogowski, Marcin

    2016-06-01

    This paper concerns keystroke dynamics, also partially in the context of touchscreen devices. The authors concentrate on the impact of database quality and propose their algorithm to test database quality issues. The algorithm is used on their own as well as the well-known Keystroke Dynamics - Benchmark Data Set database>. Following specific problems were researched: classification accuracy, development of user typing proficiency, time precision during sample acquisition, representativeness of training set, sample length.

  1. Database Description - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us Trypanosomes Database... Database Description General information of database Database name Trypanosomes Database...rmation and Systems Yata 1111, Mishima, Shizuoka 411-8540, JAPAN E mail: Database... classification Protein sequence databases Organism Taxonomy Name: Trypanosoma Taxonomy ID: 5690 Taxonomy Na...me: Homo sapiens Taxonomy ID: 9606 Database description The Trypanosomes database is a database providing th

  2. Database Description - PLACE | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us PLACE Database... Description General information of database Database name A Database of Plant Cis-acting Regu...araki 305-8602, Japan National Institute of Agrobiological Sciences E-mail : Database classification Plant database...s Organism Taxonomy Name: Tracheophyta Taxonomy ID: 58023 Database description PLACE is a database of... motifs found in plant cis-acting regulatory DNA elements based on previously pub

  3. Keyword Search in Databases

    CERN Document Server

    Yu, Jeffrey Xu; Chang, Lijun

    2009-01-01

    It has become highly desirable to provide users with flexible ways to query/search information over databases as simple as keyword search like Google search. This book surveys the recent developments on keyword search over databases, and focuses on finding structural information among objects in a database using a set of keywords. Such structural information to be returned can be either trees or subgraphs representing how the objects, that contain the required keywords, are interconnected in a relational database or in an XML database. The structural keyword search is completely different from

  4. An Interoperable Cartographic Database

    Directory of Open Access Journals (Sweden)

    Slobodanka Ključanin

    2007-05-01

    Full Text Available The concept of producing a prototype of interoperable cartographic database is explored in this paper, including the possibilities of integration of different geospatial data into the database management system and their visualization on the Internet. The implementation includes vectorization of the concept of a single map page, creation of the cartographic database in an object-relation database, spatial analysis, definition and visualization of the database content in the form of a map on the Internet. 

  5. The NCBI Taxonomy database.

    Science.gov (United States)

    Federhen, Scott

    2012-01-01

    The NCBI Taxonomy database (http://www.ncbi.nlm.nih.gov/taxonomy) is the standard nomenclature and classification repository for the International Nucleotide Sequence Database Collaboration (INSDC), comprising the GenBank, ENA (EMBL) and DDBJ databases. It includes organism names and taxonomic lineages for each of the sequences represented in the INSDC's nucleotide and protein sequence databases. The taxonomy database is manually curated by a small group of scientists at the NCBI who use the current taxonomic literature to maintain a phylogenetic taxonomy for the source organisms represented in the sequence databases. The taxonomy database is a central organizing hub for many of the resources at the NCBI, and provides a means for clustering elements within other domains of NCBI web site, for internal linking between domains of the Entrez system and for linking out to taxon-specific external resources on the web. Our primary purpose is to index the domain of sequences as conveniently as possible for our user community.

  6. On the accuracy of language trees.

    Directory of Open Access Journals (Sweden)

    Simone Pompei

    Full Text Available Historical linguistics aims at inferring the most likely language phylogenetic tree starting from information concerning the evolutionary relatedness of languages. The available information are typically lists of homologous (lexical, phonological, syntactic features or characters for many different languages: a set of parallel corpora whose compilation represents a paramount achievement in linguistics. From this perspective the reconstruction of language trees is an example of inverse problems: starting from present, incomplete and often noisy, information, one aims at inferring the most likely past evolutionary history. A fundamental issue in inverse problems is the evaluation of the inference made. A standard way of dealing with this question is to generate data with artificial models in order to have full access to the evolutionary process one is going to infer. This procedure presents an intrinsic limitation: when dealing with real data sets, one typically does not know which model of evolution is the most suitable for them. A possible way out is to compare algorithmic inference with expert classifications. This is the point of view we take here by conducting a thorough survey of the accuracy of reconstruction methods as compared with the Ethnologue expert classifications. We focus in particular on state-of-the-art distance-based methods for phylogeny reconstruction using worldwide linguistic databases. In order to assess the accuracy of the inferred trees we introduce and characterize two generalizations of standard definitions of distances between trees. Based on these scores we quantify the relative performances of the distance-based algorithms considered. Further we quantify how the completeness and the coverage of the available databases affect the accuracy of the reconstruction. Finally we draw some conclusions about where the accuracy of the reconstructions in historical linguistics stands and about the leading directions to improve

  7. 酒店网站访问者行为的多时间维度研究%Research on user behavior of hotel website on multi temporal time dimensions

    Institute of Scientific and Technical Information of China (English)

    沈阳

    2015-01-01

    基于“迈点”网站公布的酒店品牌指数 MBI 排名,利用时间日志调查系统和 Alexa 访问量查询系统,跟踪获取了一系列周、月、年内访问者行为的时间分布资料。采取多时间维度方法,描绘出一系列连续的折线来反映用户的访问趋势,分析酒店网站访问者的行为特征。研究结果表明,在周内分布特征方面,国际高端酒店网站呈现三种表现形态;国内高端酒店、经济型酒店和中端酒店网站均呈现两种表现形态。在月内分布特征方面,国际高端酒店和中端酒店网站呈现三峰态势;国内高端酒店网站呈现双峰态势;经济型酒店和精品酒店网站呈现单峰态势。在年内分布特征方面,国际和国内高端酒店、经济型酒店和中端酒店的网站访问峰值分布于不同月份;精品酒店网站波动不明显。%Based on the hotel website rankings of Maidian hotel brand MBI index,we use the time diary survey system and Alexa traffic query system to track the visitors'behavior and obtain a series of data on weeks,months,years time dimension.We a-dopt multi temporal dimensions method to describe a series of continuous lines to reflect user access tendency and analyze the be-havior trait of hotel website visitors.The research results show that international upscale hotel website presents three kinds of graphs.The domestic upscale,mid -scale hotel website presents two kinds of graphs.International upscale hotel and mid -scale hotel website presents three peaks;the domestic upscale hotel website presents two peaks;mid -scale hotel and economy hotel website presents steadiness.International upscale hotel website's,domestic upscale hotel website's,economy hotel website's,mid-scale hotel website's peaks appear in different months.The graph of boutique hotel website appears smooth and steady.

  8. Update History of This Database - Arabidopsis Phenome Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Arabidopsis Phenome Database Update History of This Database Date Update contents 2017/02/27... Arabidopsis Phenome Database English archive site is opened. - Arabidopsis Phenome Database (http://jphenom...e.info/?page_id=95) is opened. About This Database Database Description Download License Update History of This Database... Site Policy | Contact Us Update History of This Database - Arabidopsis Phenome Database | LSDB Archive ...

  9. Update History of This Database - SKIP Stemcell Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us SKIP Stemcell Database Update History of This Database Date Update contents 2017/03/13 SKIP Stemcell Database... English archive site is opened. 2013/03/29 SKIP Stemcell Database ( https://www.skip.med.k...eio.ac.jp/SKIPSearch/top?lang=en ) is opened. About This Database Database Description Download License Upda...te History of This Database Site Policy | Contact Us Update History of This Database - SKIP Stemcell Database | LSDB Archive ...

  10. Database Description - RMG | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us RMG Database... Description General information of database Database name RMG Alternative name Rice Mitochondri...ational Institute of Agrobiological Sciences E-mail : Database classification Nucleotide Sequence Databases ...Organism Taxonomy Name: Oryza sativa Japonica Group Taxonomy ID: 39947 Database description This database co...e of rice mitochondrial genome and information on the analysis results. Features and manner of utilization of database

  11. Towards Understanding Spontaneous Speech Word Accuracy vs. Concept Accuracy

    CERN Document Server

    Boros, M; Gallwitz, F; Goerz, G; Hanrieder, G; Niemann, H

    1996-01-01

    In this paper we describe an approach to automatic evaluation of both the speech recognition and understanding capabilities of a spoken dialogue system for train time table information. We use word accuracy for recognition and concept accuracy for understanding performance judgement. Both measures are calculated by comparing these modules' output with a correct reference answer. We report evaluation results for a spontaneous speech corpus with about 10000 utterances. We observed a nearly linear relationship between word accuracy and concept accuracy.

  12. The effect of atmospheric and topographic correction methods on land cover classification accuracy

    Science.gov (United States)

    Vanonckelen, Steven; Lhermitte, Stefaan; Van Rompaey, Anton

    2013-10-01

    of different land cover types in the landscape. Finally, coupled correction methods showed most efficient on weakly illuminated slopes. After correction, accuracies in the low illumination zone (cos β ≤ 0.65) were improved more than in the moderate and high illumination zones. Considering all results, best overall classification results were achieved after combination of the transmittance function correction with pixel-based Minnaert or pixel-based C-topographic correction. Furthermore, results of this bi-temporal study indicated that the topographic component had a higher influence on classification accuracy than the atmospheric component and that it is worthwhile to invest in both atmospheric and topographic corrections in a multi-temporal study.

  13. National Database of Geriatrics

    DEFF Research Database (Denmark)

    Kannegaard, Pia Nimann; Vinding, Kirsten L; Hare-Bruun, Helle

    2016-01-01

    AIM OF DATABASE: The aim of the National Database of Geriatrics is to monitor the quality of interdisciplinary diagnostics and treatment of patients admitted to a geriatric hospital unit. STUDY POPULATION: The database population consists of patients who were admitted to a geriatric hospital unit....... Geriatric patients cannot be defined by specific diagnoses. A geriatric patient is typically a frail multimorbid elderly patient with decreasing functional ability and social challenges. The database includes 14-15,000 admissions per year, and the database completeness has been stable at 90% during the past......, percentage of discharges with a rehabilitation plan, and the part of cases where an interdisciplinary conference has taken place. Data are recorded by doctors, nurses, and therapists in a database and linked to the Danish National Patient Register. DESCRIPTIVE DATA: Descriptive patient-related data include...

  14. Hazard Analysis Database Report

    CERN Document Server

    Grams, W H

    2000-01-01

    The Hazard Analysis Database was developed in conjunction with the hazard analysis activities conducted in accordance with DOE-STD-3009-94, Preparation Guide for U S . Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports, for HNF-SD-WM-SAR-067, Tank Farms Final Safety Analysis Report (FSAR). The FSAR is part of the approved Authorization Basis (AB) for the River Protection Project (RPP). This document describes, identifies, and defines the contents and structure of the Tank Farms FSAR Hazard Analysis Database and documents the configuration control changes made to the database. The Hazard Analysis Database contains the collection of information generated during the initial hazard evaluations and the subsequent hazard and accident analysis activities. The Hazard Analysis Database supports the preparation of Chapters 3 ,4 , and 5 of the Tank Farms FSAR and the Unreviewed Safety Question (USQ) process and consists of two major, interrelated data sets: (1) Hazard Analysis Database: Data from t...

  15. Conditioning Probabilistic Databases

    CERN Document Server

    Koch, Christoph

    2008-01-01

    Past research on probabilistic databases has studied the problem of answering queries on a static database. Application scenarios of probabilistic databases however often involve the conditioning of a database using additional information in the form of new evidence. The conditioning problem is thus to transform a probabilistic database of priors into a posterior probabilistic database which is materialized for subsequent query processing or further refinement. It turns out that the conditioning problem is closely related to the problem of computing exact tuple confidence values. It is known that exact confidence computation is an NP-hard problem. This has lead researchers to consider approximation techniques for confidence computation. However, neither conditioning nor exact confidence computation can be solved using such techniques. In this paper we present efficient techniques for both problems. We study several problem decomposition methods and heuristics that are based on the most successful search techn...

  16. Database design and database administration for a kindergarten

    OpenAIRE

    Vítek, Daniel

    2009-01-01

    The bachelor thesis deals with creation of database design for a standard kindergarten, installation of the designed database into the database system Oracle Database 10g Express Edition and demonstration of the administration tasks in this database system. The verification of the database was proved by a developed access application.

  17. ITS-90 Thermocouple Database

    Science.gov (United States)

    SRD 60 NIST ITS-90 Thermocouple Database (Web, free access)   Web version of Standard Reference Database 60 and NIST Monograph 175. The database gives temperature -- electromotive force (emf) reference functions and tables for the letter-designated thermocouple types B, E, J, K, N, R, S and T. These reference functions have been adopted as standards by the American Society for Testing and Materials (ASTM) and the International Electrotechnical Commission (IEC).

  18. Searching Databases with Keywords

    Institute of Scientific and Technical Information of China (English)

    Shan Wang; Kun-Long Zhang

    2005-01-01

    Traditionally, SQL query language is used to search the data in databases. However, it is inappropriate for end-users, since it is complex and hard to learn. It is the need of end-user, searching in databases with keywords, like in web search engines. This paper presents a survey of work on keyword search in databases. It also includes a brief introduction to the SEEKER system which has been developed.

  19. Specialist Bibliographic Databases

    OpenAIRE

    Gasparyan, Armen Yuri; Yessirkepov, Marlen; Voronov, Alexander A.; Trukhachev, Vladimir I.; Kostyukova, Elena I.; Gerasimov, Alexey N.; Kitas, George D.

    2016-01-01

    Specialist bibliographic databases offer essential online tools for researchers and authors who work on specific subjects and perform comprehensive and systematic syntheses of evidence. This article presents examples of the established specialist databases, which may be of interest to those engaged in multidisciplinary science communication. Access to most specialist databases is through subscription schemes and membership in professional associations. Several aggregators of information and d...

  20. Accuracy of tablet splitting.

    Science.gov (United States)

    McDevitt, J T; Gurst, A H; Chen, Y

    1998-01-01

    We attempted to determine the accuracy of manually splitting hydrochlorothiazide tablets. Ninety-four healthy volunteers each split ten 25-mg hydrochlorothiazide tablets, which were then weighed using an analytical balance. Demographics, grip and pinch strength, digit circumference, and tablet-splitting experience were documented. Subjects were also surveyed regarding their willingness to pay a premium for commercially available, lower-dose tablets. Of 1752 manually split tablet portions, 41.3% deviated from ideal weight by more than 10% and 12.4% deviated by more than 20%. Gender, age, education, and tablet-splitting experience were not predictive of variability. Most subjects (96.8%) stated a preference for commercially produced, lower-dose tablets, and 77.2% were willing to pay more for them. For drugs with steep dose-response curves or narrow therapeutic windows, the differences we recorded could be clinically relevant.

  1. Smart Location Database - Download

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  2. Database principles programming performance

    CERN Document Server

    O'Neil, Patrick

    2014-01-01

    Database: Principles Programming Performance provides an introduction to the fundamental principles of database systems. This book focuses on database programming and the relationships between principles, programming, and performance.Organized into 10 chapters, this book begins with an overview of database design principles and presents a comprehensive introduction to the concepts used by a DBA. This text then provides grounding in many abstract concepts of the relational model. Other chapters introduce SQL, describing its capabilities and covering the statements and functions of the programmi

  3. Smart Location Database - Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  4. Database Publication Practices

    DEFF Research Database (Denmark)

    Bernstein, P.A.; DeWitt, D.; Heuer, A.

    2005-01-01

    There has been a growing interest in improving the publication processes for database research papers. This panel reports on recent changes in those processes and presents an initial cut at historical data for the VLDB Journal and ACM Transactions on Database Systems.......There has been a growing interest in improving the publication processes for database research papers. This panel reports on recent changes in those processes and presents an initial cut at historical data for the VLDB Journal and ACM Transactions on Database Systems....

  5. The Danish Melanoma Database

    DEFF Research Database (Denmark)

    Hölmich, Lisbet Rosenkrantz; Klausen, Siri; Spaun, Eva

    2016-01-01

    AIM OF DATABASE: The aim of the database is to monitor and improve the treatment and survival of melanoma patients. STUDY POPULATION: All Danish patients with cutaneous melanoma and in situ melanomas must be registered in the Danish Melanoma Database (DMD). In 2014, 2,525 patients with invasive......, nature, and treatment hereof is registered. In case of death, the cause and date are included. Currently, all data are entered manually; however, data catchment from the existing registries is planned to be included shortly. DESCRIPTIVE DATA: The DMD is an old research database, but new as a clinical...

  6. Danish Gynecological Cancer Database

    DEFF Research Database (Denmark)

    Sørensen, Sarah Mejer; Bjørn, Signe Frahm; Jochumsen, Kirsten Marie

    2016-01-01

    AIM OF DATABASE: The Danish Gynecological Cancer Database (DGCD) is a nationwide clinical cancer database and its aim is to monitor the treatment quality of Danish gynecological cancer patients, and to generate data for scientific purposes. DGCD also records detailed data on the diagnostic measures...... is the registration of oncological treatment data, which is incomplete for a large number of patients. CONCLUSION: The very complete collection of available data from more registries form one of the unique strengths of DGCD compared to many other clinical databases, and provides unique possibilities for validation...

  7. Transporter Classification Database (TCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Transporter Classification Database details a comprehensive classification system for membrane transport proteins known as the Transporter Classification (TC)...

  8. IVR EFP Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database contains trip-level reports submitted by vessels participating in Exempted Fishery projects with IVR reporting requirements.

  9. Databases for Microbiologists

    Science.gov (United States)

    2015-01-01

    Databases play an increasingly important role in biology. They archive, store, maintain, and share information on genes, genomes, expression data, protein sequences and structures, metabolites and reactions, interactions, and pathways. All these data are critically important to microbiologists. Furthermore, microbiology has its own databases that deal with model microorganisms, microbial diversity, physiology, and pathogenesis. Thousands of biological databases are currently available, and it becomes increasingly difficult to keep up with their development. The purpose of this minireview is to provide a brief survey of current databases that are of interest to microbiologists. PMID:26013493

  10. Veterans Administration Databases

    Science.gov (United States)

    The Veterans Administration Information Resource Center provides database and informatics experts, customer service, expert advice, information products, and web technology to VA researchers and others.

  11. Residency Allocation Database

    Data.gov (United States)

    Department of Veterans Affairs — The Residency Allocation Database is used to determine allocation of funds for residency programs offered by Veterans Affairs Medical Centers (VAMCs). Information...

  12. Improving metacomprehension accuracy in an undergraduate course context.

    Science.gov (United States)

    Wiley, Jennifer; Griffin, Thomas D; Jaeger, Allison J; Jarosz, Andrew F; Cushen, Patrick J; Thiede, Keith W

    2016-12-01

    Students tend to have poor metacomprehension when learning from text, meaning they are not able to distinguish between what they have understood well and what they have not. Although there are a good number of studies that have explored comprehension monitoring accuracy in laboratory experiments, fewer studies have explored this in authentic course contexts. This study investigated the effect of an instructional condition that encouraged comprehension-test-expectancy and self-explanation during study on metacomprehension accuracy in the context of an undergraduate course in research methods. Results indicated that when students received this instructional condition, relative metacomprehension accuracy was better than in a comparison condition. In addition, differences were also seen in absolute metacomprehension accuracy measures, strategic study behaviors, and learning outcomes. The results of the current study demonstrate that a condition that has improved relative metacomprehension accuracy in laboratory contexts may have value in real classroom contexts as well. (PsycINFO Database Record

  13. License - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Trypanosomes Database License License to Use This Database Last updated : 2014/02/04 You may use this database...pecifies the license terms regarding the use of this database and the requirements you must follow in using this database.... The license for this database is specified in the Creative Commons... Attribution-Share Alike 2.1 Japan . If you use data from this database, please be sure attribute this database...pan is found here . With regard to this database, you are licensed to: freely access part or whole of this database

  14. DEPOT database: Reference manual and user's guide

    Energy Technology Data Exchange (ETDEWEB)

    Clancey, P.; Logg, C.

    1991-03-01

    DEPOT has been developed to provide tracking for the Stanford Linear Collider (SLC) control system equipment. For each piece of equipment entered into the database, complete location, service, maintenance, modification, certification, and radiation exposure histories can be maintained. To facilitate data entry accuracy, efficiency, and consistency, barcoding technology has been used extensively. DEPOT has been an important tool in improving the reliability of the microsystems controlling SLC. This document describes the components of the DEPOT database, the elements in the database records, and the use of the supporting programs for entering data, searching the database, and producing reports from the information.

  15. Adaptive Peak Frequency Estimation Using a Database of PARCOR Coefficients

    Directory of Open Access Journals (Sweden)

    Iiguni Youji

    2005-01-01

    Full Text Available This paper presents an adaptive peak frequency estimation method using a database that stores PARCOR coefficients as key attributes and the corresponding peak frequencies as nonkey attributes. The least-square lattice algorithm is used to recursively estimate the PARCOR coefficients to adapt to changing circumstances. The nearest neighbor to the current PARCOR coefficient is retrieved from the database, and the corresponding peak frequency is regarded as the estimation. A simultaneous execution of database construction and peak estimation with database update is performed to accelerate the processing time and to improve the estimation accuracy.

  16. Neutrosophic Relational Database Decomposition

    OpenAIRE

    Meena Arora; Ranjit Biswas; Dr. U.S.Pandey

    2011-01-01

    In this paper we present a method of decomposing a neutrosophic database relation with Neutrosophic attributes into basic relational form. Our objective is capable of manipulating incomplete as well as inconsistent information. Fuzzy relation or vague relation can only handle incomplete information. Authors are taking the Neutrosophic Relational database [8],[2] to show how imprecise data can be handled in relational schema.

  17. HIV Structural Database

    Science.gov (United States)

    SRD 102 HIV Structural Database (Web, free access)   The HIV Protease Structural Database is an archive of experimentally determined 3-D structures of Human Immunodeficiency Virus 1 (HIV-1), Human Immunodeficiency Virus 2 (HIV-2) and Simian Immunodeficiency Virus (SIV) Proteases and their complexes with inhibitors or products of substrate cleavage.

  18. Structural Ceramics Database

    Science.gov (United States)

    SRD 30 NIST Structural Ceramics Database (Web, free access)   The NIST Structural Ceramics Database (WebSCD) provides evaluated materials property data for a wide range of advanced ceramics known variously as structural ceramics, engineering ceramics, and fine ceramics.

  19. Odense Pharmacoepidemiological Database (OPED)

    DEFF Research Database (Denmark)

    Hallas, Jesper; Poulsen, Maja Hellfritzsch; Hansen, Morten Rix

    2017-01-01

    The Odense University Pharmacoepidemiological Database (OPED) is a prescription database established in 1990 by the University of Southern Denmark, covering reimbursed prescriptions from the county of Funen in Denmark and the region of Southern Denmark (1.2 million inhabitants). It is still active...

  20. The Danish Anaesthesia Database

    DEFF Research Database (Denmark)

    Antonsen, Kristian; Rosenstock, Charlotte Vallentin; Lundstrøm, Lars Hyldborg

    2016-01-01

    AIM OF DATABASE: The aim of the Danish Anaesthesia Database (DAD) is the nationwide collection of data on all patients undergoing anesthesia. Collected data are used for quality assurance, quality development, and serve as a basis for research projects. STUDY POPULATION: The DAD was founded in 2004...

  1. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1.

  2. Balkan Vegetation Database

    NARCIS (Netherlands)

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir

    2016-01-01

    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; http://www.givd.info/ID/EU-00- 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  3. Balkan Vegetation Database

    NARCIS (Netherlands)

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir

    2016-01-01

    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; http://www.givd.info/ID/EU-00- 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  4. Biological Macromolecule Crystallization Database

    Science.gov (United States)

    SRD 21 Biological Macromolecule Crystallization Database (Web, free access)   The Biological Macromolecule Crystallization Database and NASA Archive for Protein Crystal Growth Data (BMCD) contains the conditions reported for the crystallization of proteins and nucleic acids used in X-ray structure determinations and archives the results of microgravity macromolecule crystallization studies.

  5. Database Publication Practices

    DEFF Research Database (Denmark)

    Bernstein, P.A.; DeWitt, D.; Heuer, A.

    2005-01-01

    There has been a growing interest in improving the publication processes for database research papers. This panel reports on recent changes in those processes and presents an initial cut at historical data for the VLDB Journal and ACM Transactions on Database Systems....

  6. A Quality System Database

    Science.gov (United States)

    Snell, William H.; Turner, Anne M.; Gifford, Luther; Stites, William

    2010-01-01

    A quality system database (QSD), and software to administer the database, were developed to support recording of administrative nonconformance activities that involve requirements for documentation of corrective and/or preventive actions, which can include ISO 9000 internal quality audits and customer complaints.

  7. An organic database system

    NARCIS (Netherlands)

    M.L. Kersten (Martin); A.P.J.M. Siebes (Arno)

    1999-01-01

    textabstractThe pervasive penetration of database technology may suggest that we have reached the end of the database research era. The contrary is true. Emerging technology, in hardware, software, and connectivity, brings a wealth of opportunities to push technology to a new level of maturity.

  8. Atomic Spectra Database (ASD)

    Science.gov (United States)

    SRD 78 NIST Atomic Spectra Database (ASD) (Web, free access)   This database provides access and search capability for NIST critically evaluated data on atomic energy levels, wavelengths, and transition probabilities that are reasonably up-to-date. The NIST Atomic Spectroscopy Data Center has carried out these critical compilations.

  9. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1. Bib

  10. World Database of Happiness

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1995-01-01

    textabstractABSTRACT The World Database of Happiness is an ongoing register of research on subjective appreciation of life. Its purpose is to make the wealth of scattered findings accessible, and to create a basis for further meta-analytic studies. The database involves four sections:
    1. Bib

  11. Database Description - Yeast Interacting Proteins Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available Yeast Interacting Proteins Database Database Description General information of database Database name Yeast... Interacting Proteins Database Alternative name - Creator Creator Name: Takashi Ito* Creator Affiliation: Di...-4-7136-3989 FAX: +81-4-7136-3979 E-mail : Database classification Metabolic and Signaling Pathways - Protei...n-protein interactions Organism Taxonomy Name: Saccharomyces cerevisiae Taxonomy ID: 4932 Database descripti...ive yeast two-hybrid analysis of budding yeast proteins. Features and manner of utilization of database Prot

  12. Bluetooth wireless database for scoliosis clinics.

    Science.gov (United States)

    Lou, E; Fedorak, M V; Hill, D L; Raso, J V; Moreau, M J; Mahood, J K

    2003-05-01

    A database system with Bluetooth wireless connectivity has been developed so that scoliosis clinics can be run more efficiently and data can be mined for research studies without significant increases in equipment cost. The wireless database system consists of a Bluetooth-enabled laptop or PC and a Bluetooth-enabled handheld personal data assistant (PDA). Each patient has a profile in the database, which has all of his or her clinical history. Immediately prior to the examination, the orthopaedic surgeon selects a patient's profile from the database and uploads that data to the PDA over a Bluetooth wireless connection. The surgeon can view the entire clinical history of the patient while in the examination room and, at the same time, enter in any new measurements and comments from the current examination. After seeing the patient, the surgeon synchronises the newly entered information with the database wirelessly and prints a record for the chart. This combination of the database and the PDA both improves efficiency and accuracy and can save significant time, as there is less duplication of work, and no dictation is required. The equipment required to implement this solution is a Bluetooth-enabled PDA and a Bluetooth wireless transceiver for the PC or laptop.

  13. Reclamation research database

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    A reclamation research database was compiled to help stakeholders search publications and research related to the reclamation of Alberta's oil sands region. New publications are added to the database by the Cumulative Environmental Management Association (CEMA), a nonprofit association whose mandate is to develop frameworks and guidelines for the management of cumulative environmental effects in the oil sands region. A total of 514 research papers have been compiled in the database to date. Topics include recent research on hydrology, aquatic and terrestrial ecosystems, laboratory studies on biodegradation, and the effects of oil sands processing on micro-organisms. The database includes a wide variety of studies related to reconstructed wetlands as well as the ecological effects of hydrocarbons on phytoplankton and other organisms. The database format included information on research format availability, as well as information related to the author's affiliations. Links to external abstracts were provided where available, as well as details of source information.

  14. The LHCb configuration database

    CERN Document Server

    Abadie, L; Van Herwijnen, Eric; Jacobsson, R; Jost, B; Neufeld, N

    2005-01-01

    The aim of the LHCb configuration database is to store information about all the controllable devices of the detector. The experiment's control system (that uses PVSS ) will configure, start up and monitor the detector from the information in the configuration database. The database will contain devices with their properties, connectivity and hierarchy. The ability to store and rapidly retrieve huge amounts of data, and the navigability between devices are important requirements. We have collected use cases to ensure the completeness of the design. Using the entity relationship modelling technique we describe the use cases as classes with attributes and links. We designed the schema for the tables using relational diagrams. This methodology has been applied to the TFC (switches) and DAQ system. Other parts of the detector will follow later. The database has been implemented using Oracle to benefit from central CERN database support. The project also foresees the creation of tools to populate, maintain, and co...

  15. Cascadia Tsunami Deposit Database

    Science.gov (United States)

    Peters, Robert; Jaffe, Bruce; Gelfenbaum, Guy; Peterson, Curt

    2003-01-01

    The Cascadia Tsunami Deposit Database contains data on the location and sedimentological properties of tsunami deposits found along the Cascadia margin. Data have been compiled from 52 studies, documenting 59 sites from northern California to Vancouver Island, British Columbia that contain known or potential tsunami deposits. Bibliographical references are provided for all sites included in the database. Cascadia tsunami deposits are usually seen as anomalous sand layers in coastal marsh or lake sediments. The studies cited in the database use numerous criteria based on sedimentary characteristics to distinguish tsunami deposits from sand layers deposited by other processes, such as river flooding and storm surges. Several studies cited in the database contain evidence for more than one tsunami at a site. Data categories include age, thickness, layering, grainsize, and other sedimentological characteristics of Cascadia tsunami deposits. The database documents the variability observed in tsunami deposits found along the Cascadia margin.

  16. Database Description - DGBY | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us DGBY Database... Description General information of database Database name DGBY Alternative name Database for G...-12 Kannondai, Tsukuba, Ibaraki 305-8642 Japan Akira Ando TEL: +81-29-838-8066 E-mail: Database classificati...on Microarray Data and other Gene Expression Databases Organism Taxonomy Name: Sa...ccharomyces cerevisiae Taxonomy ID: 4932 Database description Baker's yeast Saccharomyces cerevisiae is an e

  17. Database Description - RPSD | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us RPSD Database... Description General information of database Database name RPSD Alternative name Summary inform...n National Institute of Agrobiological Sciences Toshimasa Yamazaki E-mail : Database classification Structure Database...idopsis thaliana Taxonomy ID: 3702 Taxonomy Name: Glycine max Taxonomy ID: 3847 Database description We have...nts such as rice, and have put together the result and related informations. This database contains the basi

  18. Reticence, Accuracy and Efficacy

    Science.gov (United States)

    Oreskes, N.; Lewandowsky, S.

    2015-12-01

    James Hansen has cautioned the scientific community against "reticence," by which he means a reluctance to speak in public about the threat of climate change. This may contribute to social inaction, with the result that society fails to respond appropriately to threats that are well understood scientifically. Against this, others have warned against the dangers of "crying wolf," suggesting that reticence protects scientific credibility. We argue that both these positions are missing an important point: that reticence is not only a matter of style but also of substance. In previous work, Bysse et al. (2013) showed that scientific projections of key indicators of climate change have been skewed towards the low end of actual events, suggesting a bias in scientific work. More recently, we have shown that scientific efforts to be responsive to contrarian challenges have led scientists to adopt the terminology of a "pause" or "hiatus" in climate warming, despite the lack of evidence to support such a conclusion (Lewandowsky et al., 2015a. 2015b). In the former case, scientific conservatism has led to under-estimation of climate related changes. In the latter case, the use of misleading terminology has perpetuated scientific misunderstanding and hindered effective communication. Scientific communication should embody two equally important goals: 1) accuracy in communicating scientific information and 2) efficacy in expressing what that information means. Scientists should strive to be neither conservative nor adventurous but to be accurate, and to communicate that accurate information effectively.

  19. The age-phenome database.

    Science.gov (United States)

    Geifman, Nophar; Rubin, Eitan

    2012-01-01

    Data linking specific ages or age ranges with disease are abundant in biomedical literature. However, these data are organized such that searching for age-phenotype relationships is difficult. Recently, we described the Age-Phenome Knowledge-base (APK), a computational platform for storage and retrieval of information concerning age-related phenotypic patterns. Here, we report that data derived from over 1.5 million human-related PubMed abstracts have been added to APK. Using a text-mining pipeline, 35,683 entries which describe relationships between age and phenotype (such as disease) have been introduced into the database. Comparing the results to those obtained by a human reader reveals that the overall accuracy of these entries is estimated to exceed 80%. The usefulness of these data for obtaining new insight regarding age-disease relationships is demonstrated using clustering analysis, which is shown to capture obvious, as well as potentially interesting relationships between diseases. In addition, a new tool for browsing and searching the APK database is presented. We thus present a unique resource and a new framework for studying age-disease relationships and other phenotypic processes.

  20. Field Plot and Accuracy Assessment Points for Palo Alto Battlefield National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Plot data were collected from 2000-2003; however, minimal attributes were maintained and a plots database was not...

  1. Field Plot and Accuracy Assessment Points for Padre Island National Seashore Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — Accuracy Assessment, Observation and Plot Points. Currently there are NO DATA in this feature class. As of December 2009, a plots database has not been developed and...

  2. Accuracy Assessment Points for Craters of the Moon National Monument and Preserve Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2008 accuracy assessment points (spatial database) created from the sample points collected at Craters of the Moon National Monument and...

  3. Accuracy Assessment Points for Washita Battlefield National Historic Site Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2006 accuracy assessment points (spatial database) created from the sample points collected at Washita Battlefield National Historic Site.

  4. Accuracy Assessment Points for Theodore Roosevelt National Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the accuracy assessment data associated with the vegetation land cover and land use geospatial database for Theodore Roosevelt National Park and...

  5. Accuracy Assessment Points for San Antonio Missions National Historical Park Vegetation Mapping Project

    Data.gov (United States)

    National Park Service, Department of the Interior — This metadata is for the 2006 accuracy assessment points (spatial database) created from the sample points collected at San Antonio Missions National Historical Park.

  6. PADB : Published Association Database

    Directory of Open Access Journals (Sweden)

    Lee Jin-Sung

    2007-09-01

    Full Text Available Abstract Background Although molecular pathway information and the International HapMap Project data can help biomedical researchers to investigate the aetiology of complex diseases more effectively, such information is missing or insufficient in current genetic association databases. In addition, only a few of the environmental risk factors are included as gene-environment interactions, and the risk measures of associations are not indexed in any association databases. Description We have developed a published association database (PADB; http://www.medclue.com/padb that includes both the genetic associations and the environmental risk factors available in PubMed database. Each genetic risk factor is linked to a molecular pathway database and the HapMap database through human gene symbols identified in the abstracts. And the risk measures such as odds ratios or hazard ratios are extracted automatically from the abstracts when available. Thus, users can review the association data sorted by the risk measures, and genetic associations can be grouped by human genes or molecular pathways. The search results can also be saved to tab-delimited text files for further sorting or analysis. Currently, PADB indexes more than 1,500,000 PubMed abstracts that include 3442 human genes, 461 molecular pathways and about 190,000 risk measures ranging from 0.00001 to 4878.9. Conclusion PADB is a unique online database of published associations that will serve as a novel and powerful resource for reviewing and interpreting huge association data of complex human diseases.

  7. Database and Expert Systems Applications

    DEFF Research Database (Denmark)

    Viborg Andersen, Kim; Debenham, John; Wagner, Roland

    submissions. The papers are organized in topical sections on workflow automation, database queries, data classification and recommendation systems, information retrieval in multimedia databases, Web applications, implementational aspects of databases, multimedia databases, XML processing, security, XML...... schemata, query evaluation, semantic processing, information retrieval, temporal and spatial databases, querying XML, organisational aspects of databases, natural language processing, ontologies, Web data extraction, semantic Web, data stream management, data extraction, distributed database systems...

  8. Glycoproteomic and glycomic databases.

    Science.gov (United States)

    Baycin Hizal, Deniz; Wolozny, Daniel; Colao, Joseph; Jacobson, Elena; Tian, Yuan; Krag, Sharon S; Betenbaugh, Michael J; Zhang, Hui

    2014-01-01

    Protein glycosylation serves critical roles in the cellular and biological processes of many organisms. Aberrant glycosylation has been associated with many illnesses such as hereditary and chronic diseases like cancer, cardiovascular diseases, neurological disorders, and immunological disorders. Emerging mass spectrometry (MS) technologies that enable the high-throughput identification of glycoproteins and glycans have accelerated the analysis and made possible the creation of dynamic and expanding databases. Although glycosylation-related databases have been established by many laboratories and institutions, they are not yet widely known in the community. Our study reviews 15 different publicly available databases and identifies their key elements so that users can identify the most applicable platform for their analytical needs. These databases include biological information on the experimentally identified glycans and glycopeptides from various cells and organisms such as human, rat, mouse, fly and zebrafish. The features of these databases - 7 for glycoproteomic data, 6 for glycomic data, and 2 for glycan binding proteins are summarized including the enrichment techniques that are used for glycoproteome and glycan identification. Furthermore databases such as Unipep, GlycoFly, GlycoFish recently established by our group are introduced. The unique features of each database, such as the analytical methods used and bioinformatical tools available are summarized. This information will be a valuable resource for the glycobiology community as it presents the analytical methods and glycosylation related databases together in one compendium. It will also represent a step towards the desired long term goal of integrating the different databases of glycosylation in order to characterize and categorize glycoproteins and glycans better for biomedical research.

  9. Update History of This Database - Trypanosomes Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Trypanosomes Database Update History of This Database Date Update contents 2014/05/07 The co...ntact information is corrected. The features and manner of utilization of the database are corrected. 2014/02/04 Trypanosomes Databas...e English archive site is opened. 2011/04/04 Trypanosomes Database ( http://www.tan...paku.org/tdb/ ) is opened. About This Database Database Description Download Lice...nse Update History of This Database Site Policy | Contact Us Update History of This Database - Trypanosomes Database | LSDB Archive ...

  10. Phase Equilibria Diagrams Database

    Science.gov (United States)

    SRD 31 NIST/ACerS Phase Equilibria Diagrams Database (PC database for purchase)   The Phase Equilibria Diagrams Database contains commentaries and more than 21,000 diagrams for non-organic systems, including those published in all 21 hard-copy volumes produced as part of the ACerS-NIST Phase Equilibria Diagrams Program (formerly titled Phase Diagrams for Ceramists): Volumes I through XIV (blue books); Annuals 91, 92, 93; High Tc Superconductors I & II; Zirconium & Zirconia Systems; and Electronic Ceramics I. Materials covered include oxides as well as non-oxide systems such as chalcogenides and pnictides, phosphates, salt systems, and mixed systems of these classes.

  11. LandIT Database

    DEFF Research Database (Denmark)

    Iftikhar, Nadeem; Pedersen, Torben Bach

    2010-01-01

    and reporting purposes. This paper presents the LandIT database; which is result of the LandIT project, which refers to an industrial collaboration project that developed technologies for communication and data integration between farming devices and systems. The LandIT database in principal is based...... on the ISOBUS standard; however the standard is extended with additional requirements, such as gradual data aggregation and flexible exchange of farming data. This paper describes the conceptual and logical schemas of the proposed database based on a real-life farming case study....

  12. ALICE Geometry Database

    CERN Document Server

    Santo, J

    1999-01-01

    The ALICE Geometry Database project consists of the development of a set of data structures to store the geometrical information of the ALICE Detector. This Database will be used in Simulation, Reconstruction and Visualisation and will interface with existing CAD systems and Geometrical Modellers.At the present time, we are able to read a complete GEANT3 geometry, to store it in our database and to visualise it. On disk, we store different geometry files in hierarchical fashion, and all the nodes, materials, shapes, configurations and transformations distributed in this tree structure. The present status of the prototype and its future evolution will be presented.

  13. Database machine performance

    Energy Technology Data Exchange (ETDEWEB)

    Cesarini, F.; Salza, S.

    1987-01-01

    This book is devoted to the important problem of database machine performance evaluation. The book presents several methodological proposals and case studies, that have been developed within an international project supported by the European Economic Community on Database Machine Evaluation Techniques and Tools in the Context of the Real Time Processing. The book gives an overall view of the modeling methodologies and the evaluation strategies that can be adopted to analyze the performance of the database machine. Moreover, it includes interesting case studies and an extensive bibliography.

  14. Product Licenses Database Application

    CERN Document Server

    Tonkovikj, Petar

    2016-01-01

    The goal of this project is to organize and centralize the data about software tools available to CERN employees, as well as provide a system that would simplify the license management process by providing information about the available licenses and their expiry dates. The project development process is consisted of two steps: modeling the products (software tools), product licenses, legal agreements and other data related to these entities in a relational database and developing the front-end user interface so that the user can interact with the database. The result is an ASP.NET MVC web application with interactive views for displaying and managing the data in the underlying database.

  15. Plant Genome Duplication Database.

    Science.gov (United States)

    Lee, Tae-Ho; Kim, Junah; Robertson, Jon S; Paterson, Andrew H

    2017-01-01

    Genome duplication, widespread in flowering plants, is a driving force in evolution. Genome alignments between/within genomes facilitate identification of homologous regions and individual genes to investigate evolutionary consequences of genome duplication. PGDD (the Plant Genome Duplication Database), a public web service database, provides intra- or interplant genome alignment information. At present, PGDD contains information for 47 plants whose genome sequences have been released. Here, we describe methods for identification and estimation of dates of genome duplication and speciation by functions of PGDD.The database is freely available at http://chibba.agtec.uga.edu/duplication/.

  16. LandIT Database

    DEFF Research Database (Denmark)

    Iftikhar, Nadeem; Pedersen, Torben Bach

    2010-01-01

    and reporting purposes. This paper presents the LandIT database; which is result of the LandIT project, which refers to an industrial collaboration project that developed technologies for communication and data integration between farming devices and systems. The LandIT database in principal is based...... on the ISOBUS standard; however the standard is extended with additional requirements, such as gradual data aggregation and flexible exchange of farming data. This paper describes the conceptual and logical schemas of the proposed database based on a real-life farming case study....

  17. Danish Pancreatic Cancer Database

    DEFF Research Database (Denmark)

    Fristrup, Claus; Detlefsen, Sönke; Palnæs Hansen, Carsten

    2016-01-01

    AIM OF DATABASE: The Danish Pancreatic Cancer Database aims to prospectively register the epidemiology, diagnostic workup, diagnosis, treatment, and outcome of patients with pancreatic cancer in Denmark at an institutional and national level. STUDY POPULATION: Since May 1, 2011, all patients......, and survival. The results are published annually. CONCLUSION: The Danish Pancreatic Cancer Database has registered data on 2,217 patients with microscopically verified ductal adenocarcinoma of the pancreas. The data have been obtained nationwide over a period of 4 years and 2 months. The completeness...

  18. ARTI Refrigerant Database

    Energy Technology Data Exchange (ETDEWEB)

    Calm, J.M. [Calm (James M.), Great Falls, VA (United States)

    1994-05-27

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  19. Kansas Cartographic Database (KCD)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas Cartographic Database (KCD) is an exact digital representation of selected features from the USGS 7.5 minute topographic map series. Features that are...

  20. Records Management Database

    Data.gov (United States)

    US Agency for International Development — The Records Management Database is tool created in Microsoft Access specifically for USAID use. It contains metadata in order to access and retrieve the information...

  1. OTI Activity Database

    Data.gov (United States)

    US Agency for International Development — OTI's worldwide activity database is a simple and effective information system that serves as a program management, tracking, and reporting tool. In each country,...

  2. Children's Culture Database (CCD)

    DEFF Research Database (Denmark)

    Wanting, Birgit

    a Dialogue inspired database with documentation, network (individual and institutional profiles) and current news , paper presented at the research seminar: Electronic access to fiction, Copenhagen, November 11-13, 1996...

  3. Danish Urogynaecological Database

    DEFF Research Database (Denmark)

    Hansen, Ulla Darling; Gradel, Kim Oren; Larsen, Michael Due

    2016-01-01

    The Danish Urogynaecological Database is established in order to ensure high quality of treatment for patients undergoing urogynecological surgery. The database contains details of all women in Denmark undergoing incontinence surgery or pelvic organ prolapse surgery amounting to ~5,200 procedures...... per year. The variables are collected along the course of treatment of the patient from the referral to a postoperative control. Main variables are prior obstetrical and gynecological history, symptoms, symptom-related quality of life, objective urogynecological findings, type of operation......, complications if relevant, implants used if relevant, 3-6-month postoperative recording of symptoms, if any. A set of clinical quality indicators is being maintained by the steering committee for the database and is published in an annual report which also contains extensive descriptive statistics. The database...

  4. Fine Arts Database (FAD)

    Data.gov (United States)

    General Services Administration — The Fine Arts Database records information on federally owned art in the control of the GSA; this includes the location, current condition and information on artists.

  5. Rat Genome Database (RGD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Rat Genome Database (RGD) is a collaborative effort between leading research institutions involved in rat genetic and genomic research to collect, consolidate,...

  6. The Exoplanet Orbit Database

    CERN Document Server

    Wright, Jason T; Marcy, Geoffrey W; Han, Eunkyu; Feng, Ying; Johnson, John Asher; Howard, Andrew W; Valenti, Jeff A; Anderson, Jay; Piskunov, Nikolai

    2010-01-01

    We present a database of well determined orbital parameters of exoplanets. This database comprises spectroscopic orbital elements measured for 421 planets orbiting 357 stars from radial velocity and transit measurements as reported in the literature. We have also compiled fundamental transit parameters, stellar parameters, and the method used for the planets discovery. This Exoplanet Orbit Database includes all planets with robust, well measured orbital parameters reported in peer-reviewed articles. The database is available in a searchable, filterable, and sortable form on the Web at http://exoplanets.org through the Exoplanets Data Explorer Table, and the data can be plotted and explored through the Exoplanets Data Explorer Plotter. We use the Data Explorer to generate publication-ready plots giving three examples of the signatures of exoplanet migration and dynamical evolution: We illustrate the character of the apparent correlation between mass and period in exoplanet orbits, the selection different biase...

  7. National Geochemical Database: Concentrate

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geochemistry of concentrates from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are from the continental US and...

  8. National Geochemical Database: Soil

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geochemical analysis of soil samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are from the continental US...

  9. National Geochemical Database: Sediment

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geochemical analysis of sediment samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are of stream sediment in...

  10. The Danish Urogynaecological Database

    DEFF Research Database (Denmark)

    Guldberg, Rikke; Brostrøm, Søren; Hansen, Jesper Kjær

    2013-01-01

    INTRODUCTION AND HYPOTHESIS: The Danish Urogynaecological Database (DugaBase) is a nationwide clinical database established in 2006 to monitor, ensure and improve the quality of urogynaecological surgery. We aimed to describe its establishment and completeness and to validate selected variables....... This is the first study based on data from the DugaBase. METHODS: The database completeness was calculated as a comparison between urogynaecological procedures reported to the Danish National Patient Registry and to the DugaBase. Validity was assessed for selected variables from a random sample of 200 women...... in the DugaBase from 1 January 2009 to 31 October 2010, using medical records as a reference. RESULTS: A total of 16,509 urogynaecological procedures were registered in the DugaBase by 31 December 2010. The database completeness has increased by calendar time, from 38.2 % in 2007 to 93.2 % in 2010 for public...

  11. The Danish Depression Database

    DEFF Research Database (Denmark)

    Videbech, Poul Bror Hemming; Deleuran, Anette

    2016-01-01

    AIM OF DATABASE: The purpose of the Danish Depression Database (DDD) is to monitor and facilitate the improvement of the quality of the treatment of depression in Denmark. Furthermore, the DDD has been designed to facilitate research. STUDY POPULATION: Inpatients as well as outpatients...... as an evaluation of the risk of suicide are measured before and after treatment. Whether psychiatric aftercare has been scheduled for inpatients and the rate of rehospitalization are also registered. DESCRIPTIVE DATA: The database was launched in 2011. Every year since then ~5,500 inpatients and 7,500 outpatients...... have been registered annually in the database. A total of 24,083 inpatients and 29,918 outpatients have been registered. The DDD produces an annual report published on the Internet. CONCLUSION: The DDD can become an important tool for quality improvement and research, when the reporting is more...

  12. Molecular marker databases.

    Science.gov (United States)

    Lai, Kaitao; Lorenc, Michał Tadeusz; Edwards, David

    2015-01-01

    The detection and analysis of genetic variation plays an important role in plant breeding and this role is increasing with the continued development of genome sequencing technologies. Molecular genetic markers are important tools to characterize genetic variation and assist with genomic breeding. Processing and storing the growing abundance of molecular marker data being produced requires the development of specific bioinformatics tools and advanced databases. Molecular marker databases range from species specific through to organism wide and often host a variety of additional related genetic, genomic, or phenotypic information. In this chapter, we will present some of the features of plant molecular genetic marker databases, highlight the various types of marker resources, and predict the potential future direction of crop marker databases.

  13. Consumer Product Category Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Chemical and Product Categories database (CPCat) catalogs the use of over 40,000 chemicals and their presence in different consumer products. The chemical use...

  14. Eldercare Locator Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Eldercare Locator is a searchable database that allows a user to search via zip code or city/ state for agencies at the State and local levels that provide...

  15. Drycleaner Database - Region 7

    Data.gov (United States)

    U.S. Environmental Protection Agency — THIS DATA ASSET NO LONGER ACTIVE: This is metadata documentation for the Region 7 Drycleaner Database (R7DryClnDB) which tracks all Region7 drycleaners who notify...

  16. Reach Address Database (RAD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reach Address Database (RAD) stores the reach address of each Water Program feature that has been linked to the underlying surface water features (streams,...

  17. Toxicity Reference Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Toxicity Reference Database (ToxRefDB) contains approximately 30 years and $2 billion worth of animal studies. ToxRefDB allows scientists and the interested...

  18. 1988 Spitak Earthquake Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1988 Spitak Earthquake database is an extensive collection of geophysical and geological data, maps, charts, images and descriptive text pertaining to the...

  19. Hawaii bibliographic database

    Science.gov (United States)

    Wright, Thomas L.; Takahashi, Taeko Jane

    The Hawaii bibliographic database has been created to contain all of the literature, from 1779 to the present, pertinent to the volcanological history of the Hawaiian-Emperor volcanic chain. References are entered in a PC- and Macintosh-compatible EndNote Plus bibliographic database with keywords and s or (if no ) with annotations as to content. Keywords emphasize location, discipline, process, identification of new chemical data or age determinations, and type of publication. The database is updated approximately three times a year and is available to upload from an ftp site. The bibliography contained 8460 references at the time this paper was submitted for publication. Use of the database greatly enhances the power and completeness of library searches for anyone interested in Hawaiian volcanism.

  20. Food Habits Database (FHDBS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NEFSC Food Habits Database has two major sources of data. The first, and most extensive, is the standard NEFSC Bottom Trawl Surveys Program. During these...

  1. NLCD 2011 database

    Data.gov (United States)

    U.S. Environmental Protection Agency — National Land Cover Database 2011 (NLCD 2011) is the most recent national land cover product created by the Multi-Resolution Land Characteristics (MRLC) Consortium....

  2. Mouse Phenome Database (MPD)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Mouse Phenome Database (MPD) has characterizations of hundreds of strains of laboratory mice to facilitate translational discoveries and to assist in selection...

  3. Disaster Debris Recovery Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The US EPA Region 5 Disaster Debris Recovery Database includes public datasets of over 3,500 composting facilities, demolition contractors, haulers, transfer...

  4. National Geochemical Database: Sediment

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Geochemical analysis of sediment samples from the National Geochemical Database. Primarily inorganic elemental concentrations, most samples are of stream sediment...

  5. Uranium Location Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — A GIS compiled locational database in Microsoft Access of ~15,000 mines with uranium occurrence or production, primarily in the western United States. The metadata...

  6. National Assessment Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Assessment Database stores and tracks state water quality assessment decisions, Total Maximum Daily Loads (TMDLs) and other watershed plans designed to...

  7. Household Products Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — This database links over 4,000 consumer brands to health effects from Material Safety Data Sheets (MSDS) provided by the manufacturers and allows scientists and...

  8. Dissolution Methods Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — For a drug product that does not have a dissolution test method in the United States Pharmacopeia (USP), the FDA Dissolution Methods Database provides information on...

  9. ATLAS DAQ Configuration Databases

    Institute of Scientific and Technical Information of China (English)

    I.Alexandrov; A.Amorim; 等

    2001-01-01

    The configuration databases are an important part of the Trigger/DAQ system of the future ATLAS experiment .This paper describes their current status giving details of architecture,implementation,test results and plans for future work.

  10. Venus Crater Database

    Data.gov (United States)

    National Aeronautics and Space Administration — This web page leads to a database of images and information about the 900 or so impact craters on the surface of Venus by diameter, latitude, and name.

  11. Global Volcano Locations Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC maintains a database of over 1,500 volcano locations obtained from the Smithsonian Institution Global Volcanism Program, Volcanoes of the World publication. The...

  12. IVR RSA Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This database contains trip-level reports submitted by vessels participating in Research Set-Aside projects with IVR reporting requirements.

  13. Dissolution Methods Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — For a drug product that does not have a dissolution test method in the United States Pharmacopeia (USP), the FDA Dissolution Methods Database provides information on...

  14. Chemical Kinetics Database

    Science.gov (United States)

    SRD 17 NIST Chemical Kinetics Database (Web, free access)   The NIST Chemical Kinetics Database includes essentially all reported kinetics results for thermal gas-phase chemical reactions. The database is designed to be searched for kinetics data based on the specific reactants involved, for reactions resulting in specified products, for all the reactions of a particular species, or for various combinations of these. In addition, the bibliography can be searched by author name or combination of names. The database contains in excess of 38,000 separate reaction records for over 11,700 distinct reactant pairs. These data have been abstracted from over 12,000 papers with literature coverage through early 2000.

  15. Medicaid CHIP ESPC Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Environmental Scanning and Program Characteristic (ESPC) Database is in a Microsoft (MS) Access format and contains Medicaid and CHIP data, for the 50 states and...

  16. Medicare Coverage Database

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medicare Coverage Database (MCD) contains all National Coverage Determinations (NCDs) and Local Coverage Determinations (LCDs), local articles, and proposed NCD...

  17. Determining Geometric Accuracy in Turning

    Institute of Scientific and Technical Information of China (English)

    Kwong; Chi; Kit; A; Geddam

    2002-01-01

    Mechanical components machined to high levels of ac cu racy are vital to achieve various functional requirements in engineering product s. In particular, the geometric accuracy of turned components play an important role in determining the form, fit and function of mechanical assembly requiremen ts. The geometric accuracy requirements of turned components are usually specifi ed in terms of roundness, straightness, cylindricity and concentricity. In pract ice, the accuracy specifications achievable are infl...

  18. The Jungle Database Search Engine

    DEFF Research Database (Denmark)

    Bøhlen, Michael Hanspeter; Bukauskas, Linas; Dyreson, Curtis

    1999-01-01

    Information spread in in databases cannot be found by current search engines. A database search engine is capable to access and advertise database on the WWW. Jungle is a database search engine prototype developed at Aalborg University. Operating through JDBC connections to remote databases, Jungle...

  19. Neutrosophic Relational Database Decomposition

    Directory of Open Access Journals (Sweden)

    Meena Arora

    2011-08-01

    Full Text Available In this paper we present a method of decomposing a neutrosophic database relation with Neutrosophic attributes into basic relational form. Our objective is capable of manipulating incomplete as well as inconsistent information. Fuzzy relation or vague relation can only handle incomplete information. Authors are taking the Neutrosophic Relational database [8],[2] to show how imprecise data can be handled in relational schema.

  20. Database on Wind Characteristics

    DEFF Research Database (Denmark)

    Højstrup, J.; Ejsing Jørgensen, Hans; Lundtang Petersen, Erik

    1999-01-01

    his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061......his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061...

  1. Querying genomic databases

    Energy Technology Data Exchange (ETDEWEB)

    Baehr, A.; Hagstrom, R.; Joerg, D.; Overbeek, R.

    1991-09-01

    A natural-language interface has been developed that retrieves genomic information by using a simple subset of English. The interface spares the biologist from the task of learning database-specific query languages and computer programming. Currently, the interface deals with the E. coli genome. It can, however, be readily extended and shows promise as a means of easy access to other sequenced genomic databases as well.

  2. Fashion Information Database

    Institute of Scientific and Technical Information of China (English)

    LI Jun; WU Hai-yan; WANG Yun-yi

    2002-01-01

    In the field of fashion industry, it is a bottleneck of how to control and apply the information in the procedure of fashion merchandising. By the aid of digital technology,a perfect and practical fashion information database could be established so that high- quality and efficient,low-cost and characteristic fashion merchandising system could be realized. The basic structure of fashion information database is discussed.

  3. The Gun Violence Database

    OpenAIRE

    Pavlick, Ellie; Callison-Burch, Chris

    2016-01-01

    We describe the Gun Violence Database (GVDB), a large and growing database of gun violence incidents in the United States. The GVDB is built from the detailed information found in local news reports about gun violence, and is constructed via a large-scale crowdsourced annotation effort through our web site, http://gun-violence.org/. We argue that centralized and publicly available data about gun violence can facilitate scientific, fact-based discussion about a topic that is often dominated by...

  4. Database computing in HEP

    Science.gov (United States)

    Day, C. T.; Loken, S.; Macfarlane, J. F.; May, E.; Lifka, D.; Lusk, E.; Price, L. E.; Baden, A.; Grossman, R.; Qin, X.

    1992-01-01

    The major SSC experiments are expected to produce up to 1 Petabyte of data per year each. Once the primary reconstruction is completed by farms of inexpensive processors, I/O becomes a major factor in further analysis of the data. We believe that the application of database techniques can significantly reduce the I/O performed in these analyses. We present examples of such I/O reductions in prototypes based on relational and object-oriented databases of CDF data samples.

  5. Database on Wind Characteristics

    DEFF Research Database (Denmark)

    Højstrup, J.; Ejsing Jørgensen, Hans; Lundtang Petersen, Erik

    1999-01-01

    his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061......his report describes the work and results of the project: Database on Wind Characteristics which was sponsered partly by the European Commision within the framework of JOULE III program under contract JOR3-CT95-0061...

  6. Specialist Bibliographic Databases.

    Science.gov (United States)

    Gasparyan, Armen Yuri; Yessirkepov, Marlen; Voronov, Alexander A; Trukhachev, Vladimir I; Kostyukova, Elena I; Gerasimov, Alexey N; Kitas, George D

    2016-05-01

    Specialist bibliographic databases offer essential online tools for researchers and authors who work on specific subjects and perform comprehensive and systematic syntheses of evidence. This article presents examples of the established specialist databases, which may be of interest to those engaged in multidisciplinary science communication. Access to most specialist databases is through subscription schemes and membership in professional associations. Several aggregators of information and database vendors, such as EBSCOhost and ProQuest, facilitate advanced searches supported by specialist keyword thesauri. Searches of items through specialist databases are complementary to those through multidisciplinary research platforms, such as PubMed, Web of Science, and Google Scholar. Familiarizing with the functional characteristics of biomedical and nonbiomedical bibliographic search tools is mandatory for researchers, authors, editors, and publishers. The database users are offered updates of the indexed journal lists, abstracts, author profiles, and links to other metadata. Editors and publishers may find particularly useful source selection criteria and apply for coverage of their peer-reviewed journals and grey literature sources. These criteria are aimed at accepting relevant sources with established editorial policies and quality controls.

  7. Information Retrieval in Telemedicine: a Comparative Study on Bibliographic Databases

    Science.gov (United States)

    Ahmadi, Maryam; Sarabi, Roghayeh Ershad; Orak, Roohangiz Jamshidi; Bahaadinbeigy, Kambiz

    2015-01-01

    Background and Aims: The first step in each systematic review is selection of the most valid database that can provide the highest number of relevant references. This study was carried out to determine the most suitable database for information retrieval in telemedicine field. Methods: Cinhal, PubMed, Web of Science and Scopus databases were searched for telemedicine matched with Education, cost benefit and patient satisfaction. After analysis of the obtained results, the accuracy coefficient, sensitivity, uniqueness and overlap of databases were calculated. Results: The studied databases differed in the number of retrieved articles. PubMed was identified as the most suitable database for retrieving information on the selected topics with the accuracy and sensitivity ratios of 50.7% and 61.4% respectively. The uniqueness percent of retrieved articles ranged from 38% for Pubmed to 3.0% for Cinhal. The highest overlap rate (18.6%) was found between PubMed and Web of Science. Less than 1% of articles have been indexed in all searched databases. Conclusion: PubMed is suggested as the most suitable database for starting search in telemedicine and after PubMed, Scopus and Web of Science can retrieve about 90% of the relevant articles. PMID:26236086

  8. Update History of This Database - Yeast Interacting Proteins Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us ...Yeast Interacting Proteins Database Update History of This Database Date Update contents 2010/03/29 Yeast In...t This Database Database Description Download License Update History of This Database Site Policy | Contact Us Update History

  9. Test Expectancy Affects Metacomprehension Accuracy

    Science.gov (United States)

    Thiede, Keith W.; Wiley, Jennifer; Griffin, Thomas D.

    2011-01-01

    Background: Theory suggests that the accuracy of metacognitive monitoring is affected by the cues used to judge learning. Researchers have improved monitoring accuracy by directing attention to more appropriate cues; however, this is the first study to more directly point students to more appropriate cues using instructions regarding tests and…

  10. Classification Accuracy Is Not Enough

    DEFF Research Database (Denmark)

    Sturm, Bob L.

    2013-01-01

    A recent review of the research literature evaluating music genre recognition (MGR) systems over the past two decades shows that most works (81\\%) measure the capacity of a system to recognize genre by its classification accuracy. We show here, by implementing and testing three categorically diff...... classification accuracy obscures the aim of MGR: to select labels indistinguishable from those a person would choose....

  11. Surgery Risk Assessment (SRA) Database

    Data.gov (United States)

    Department of Veterans Affairs — The Surgery Risk Assessment (SRA) database is part of the VA Surgical Quality Improvement Program (VASQIP). This database contains assessments of selected surgical...

  12. Accessing and using chemical databases

    DEFF Research Database (Denmark)

    Nikolov, Nikolai Georgiev; Pavlov, Todor; Niemelä, Jay Russell

    2013-01-01

    Computer-based representation of chemicals makes it possible to organize data in chemical databases-collections of chemical structures and associated properties. Databases are widely used wherever efficient processing of chemical information is needed, including search, storage, retrieval......, and dissemination. Structure and functionality of chemical databases are considered. The typical kinds of information found in a chemical database are considered-identification, structural, and associated data. Functionality of chemical databases is presented, with examples of search and access types. More details...... are included about the OASIS database and platform and the Danish (Q)SAR Database online. Various types of chemical database resources are discussed, together with a list of examples....

  13. Danish clinical databases: An overview

    DEFF Research Database (Denmark)

    Green, Anders

    2011-01-01

    Clinical databases contain data related to diagnostic procedures, treatments and outcomes. In 2001, a scheme was introduced for the approval, supervision and support to clinical databases in Denmark....

  14. Scalable Earth-observation Analytics for Geoscientists: Spacetime Extensions to the Array Database SciDB

    Science.gov (United States)

    Appel, Marius; Lahn, Florian; Pebesma, Edzer; Buytaert, Wouter; Moulds, Simon

    2016-04-01

    Today's amount of freely available data requires scientists to spend large parts of their work on data management. This is especially true in environmental sciences when working with large remote sensing datasets, such as obtained from earth-observation satellites like the Sentinel fleet. Many frameworks like SpatialHadoop or Apache Spark address the scalability but target programmers rather than data analysts, and are not dedicated to imagery or array data. In this work, we use the open-source data management and analytics system SciDB to bring large earth-observation datasets closer to analysts. Its underlying data representation as multidimensional arrays fits naturally to earth-observation datasets, distributes storage and computational load over multiple instances by multidimensional chunking, and also enables efficient time-series based analyses, which is usually difficult using file- or tile-based approaches. Existing interfaces to R and Python furthermore allow for scalable analytics with relatively little learning effort. However, interfacing SciDB and file-based earth-observation datasets that come as tiled temporal snapshots requires a lot of manual bookkeeping during ingestion, and SciDB natively only supports loading data from CSV-like and custom binary formatted files, which currently limits its practical use in earth-observation analytics. To make it easier to work with large multi-temporal datasets in SciDB, we developed software tools that enrich SciDB with earth observation metadata and allow working with commonly used file formats: (i) the SciDB extension library scidb4geo simplifies working with spatiotemporal arrays by adding relevant metadata to the database and (ii) the Geospatial Data Abstraction Library (GDAL) driver implementation scidb4gdal allows to ingest and export remote sensing imagery from and to a large number of file formats. Using added metadata on temporal resolution and coverage, the GDAL driver supports time-based ingestion of

  15. ADANS database specification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-16

    The purpose of the Air Mobility Command (AMC) Deployment Analysis System (ADANS) Database Specification (DS) is to describe the database organization and storage allocation and to provide the detailed data model of the physical design and information necessary for the construction of the parts of the database (e.g., tables, indexes, rules, defaults). The DS includes entity relationship diagrams, table and field definitions, reports on other database objects, and a description of the ADANS data dictionary. ADANS is the automated system used by Headquarters AMC and the Tanker Airlift Control Center (TACC) for airlift planning and scheduling of peacetime and contingency operations as well as for deliberate planning. ADANS also supports planning and scheduling of Air Refueling Events by the TACC and the unit-level tanker schedulers. ADANS receives input in the form of movement requirements and air refueling requests. It provides a suite of tools for planners to manipulate these requirements/requests against mobility assets and to develop, analyze, and distribute schedules. Analysis tools are provided for assessing the products of the scheduling subsystems, and editing capabilities support the refinement of schedules. A reporting capability provides formatted screen, print, and/or file outputs of various standard reports. An interface subsystem handles message traffic to and from external systems. The database is an integral part of the functionality summarized above.

  16. The CAPEC Database

    DEFF Research Database (Denmark)

    Nielsen, Thomas Lund; Abildskov, Jens; Harper, Peter Mathias

    2001-01-01

    The Computer-Aided Process Engineering Center (CAPEC) database of measured data was established with the aim to promote greater data exchange in the chemical engineering community. The target properties are pure component properties, mixture properties, and special drug solubility data. The datab......The Computer-Aided Process Engineering Center (CAPEC) database of measured data was established with the aim to promote greater data exchange in the chemical engineering community. The target properties are pure component properties, mixture properties, and special drug solubility data....... The database divides pure component properties into primary, secondary, and functional properties. Mixture properties are categorized in terms of the number of components in the mixture and the number of phases present. The compounds in the database have been classified on the basis of the functional groups...... in the compound. This classification makes the CAPEC database a very useful tool, for example, in the development of new property models, since properties of chemically similar compounds are easily obtained. A program with efficient search and retrieval functions of properties has been developed....

  17. FishTraits Database

    Science.gov (United States)

    Angermeier, Paul L.; Frimpong, Emmanuel A.

    2009-01-01

    The need for integrated and widely accessible sources of species traits data to facilitate studies of ecology, conservation, and management has motivated development of traits databases for various taxa. In spite of the increasing number of traits-based analyses of freshwater fishes in the United States, no consolidated database of traits of this group exists publicly, and much useful information on these species is documented only in obscure sources. The largely inaccessible and unconsolidated traits information makes large-scale analysis involving many fishes and/or traits particularly challenging. FishTraits is a database of >100 traits for 809 (731 native and 78 exotic) fish species found in freshwaters of the conterminous United States, including 37 native families and 145 native genera. The database contains information on four major categories of traits: (1) trophic ecology, (2) body size and reproductive ecology (life history), (3) habitat associations, and (4) salinity and temperature tolerances. Information on geographic distribution and conservation status is also included. Together, we refer to the traits, distribution, and conservation status information as attributes. Descriptions of attributes are available here. Many sources were consulted to compile attributes, including state and regional species accounts and other databases.

  18. The Danish Depression Database

    Directory of Open Access Journals (Sweden)

    Videbech P

    2016-10-01

    Full Text Available Poul Videbech,1 Anette Deleuran2 1Mental Health Centre Glostrup, Department of Clinical Medicine, University of Copenhagen, Glostrup, 2Psychiatric Centre Amager, Copenhagen S, Denmark Aim of database: The purpose of the Danish Depression Database (DDD is to monitor and facilitate the improvement of the quality of the treatment of depression in Denmark. Furthermore, the DDD has been designed to facilitate research. Study population: Inpatients as well as outpatients with depression, aged above 18 years, and treated in the public psychiatric hospital system were enrolled. Main variables: Variables include whether the patient has been thoroughly somatically examined and has been interviewed about the psychopathology by a specialist in psychiatry. The Hamilton score as well as an evaluation of the risk of suicide are measured before and after treatment. Whether psychiatric aftercare has been scheduled for inpatients and the rate of rehospitalization are also registered. Descriptive data: The database was launched in 2011. Every year since then ~5,500 inpatients and 7,500 outpatients have been registered annually in the database. A total of 24,083 inpatients and 29,918 outpatients have been registered. The DDD produces an annual report published on the Internet. Conclusion: The DDD can become an important tool for quality improvement and research, when the reporting is more complete. Keywords: quality assurance, suicide, somatic diseases, national database

  19. The Chandra Bibliography Database

    Science.gov (United States)

    Rots, A. H.; Winkelman, S. L.; Paltani, S.; Blecksmith, S. E.; Bright, J. D.

    2004-07-01

    Early in the mission, the Chandra Data Archive started the development of a bibliography database, tracking publications in refereed journals and on-line conference proceedings that are based on Chandra observations, allowing our users to link directly to articles in the ADS from our archive, and to link to the relevant data in the archive from the ADS entries. Subsequently, we have been working closely with the ADS and other data centers, in the context of the ADEC-ITWG, on standardizing the literature-data linking. We have also extended our bibliography database to include all Chandra-related articles and we are also keeping track of the number of citations of each paper. Obviously, in addition to providing valuable services to our users, this database allows us to extract a wide variety of statistical information. The project comprises five components: the bibliography database-proper, a maintenance database, an interactive maintenance tool, a user browsing interface, and a web services component for exchanging information with the ADS. All of these elements are nearly mission-independent and we intend make the package as a whole available for use by other data centers. The capabilities thus provided represent support for an essential component of the Virtual Observatory.

  20. Multimodal Biometric Systems - Study to Improve Accuracy and Performance

    CERN Document Server

    Sasidhar, K; Ramakrishna, Kolikipogu; KailasaRao, K

    2010-01-01

    Biometrics is the science and technology of measuring and analyzing biological data of human body, extracting a feature set from the acquired data, and comparing this set against to the template set in the database. Experimental studies show that Unimodal biometric systems had many disadvantages regarding performance and accuracy. Multimodal biometric systems perform better than unimodal biometric systems and are popular even more complex also. We examine the accuracy and performance of multimodal biometric authentication systems using state of the art Commercial Off- The-Shelf (COTS) products. Here we discuss fingerprint and face biometric systems, decision and fusion techniques used in these systems. We also discuss their advantage over unimodal biometric systems.

  1. Open Geoscience Database

    Science.gov (United States)

    Bashev, A.

    2012-04-01

    Currently there is an enormous amount of various geoscience databases. Unfortunately the only users of the majority of the databases are their elaborators. There are several reasons for that: incompaitability, specificity of tasks and objects and so on. However the main obstacles for wide usage of geoscience databases are complexity for elaborators and complication for users. The complexity of architecture leads to high costs that block the public access. The complication prevents users from understanding when and how to use the database. Only databases, associated with GoogleMaps don't have these drawbacks, but they could be hardly named "geoscience" Nevertheless, open and simple geoscience database is necessary at least for educational purposes (see our abstract for ESSI20/EOS12). We developed a database and web interface to work with them and now it is accessible at maps.sch192.ru. In this database a result is a value of a parameter (no matter which) in a station with a certain position, associated with metadata: the date when the result was obtained; the type of a station (lake, soil etc); the contributor that sent the result. Each contributor has its own profile, that allows to estimate the reliability of the data. The results can be represented on GoogleMaps space image as a point in a certain position, coloured according to the value of the parameter. There are default colour scales and each registered user can create the own scale. The results can be also extracted in *.csv file. For both types of representation one could select the data by date, object type, parameter type, area and contributor. The data are uploaded in *.csv format: Name of the station; Lattitude(dd.dddddd); Longitude(ddd.dddddd); Station type; Parameter type; Parameter value; Date(yyyy-mm-dd). The contributor is recognised while entering. This is the minimal set of features that is required to connect a value of a parameter with a position and see the results. All the complicated data

  2. Database Vs Data Warehouse

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available Data warehouse technology includes a set of concepts and methods that offer the users useful information for decision making. The necessity to build a data warehouse arises from the necessity to improve the quality of information in the organization. The date proceeding from different sources, having a variety of forms - both structured and unstructured, are filtered according to business rules and are integrated in a single large data collection. Using informatics solutions, managers have understood that data stored in operational systems - including databases, are an informational gold mine that must be exploited. Data warehouses have been developed to answer the increasing demands for complex analysis, which could not be properly achieved with operational databases. The present paper emphasizes some of the criteria that information application developers can use in order to choose between a database solution or a data warehouse one.

  3. The LHCb configuration database

    CERN Document Server

    Abadie, Lana; Gaspar, Clara; Jacobsson, Richard; Jost, Beat; Neufeld, Niko

    2005-01-01

    The Experiment Control System (ECS) will handle the monitoring, configuration and operation of all the LHCb experimental equipment. All parameters required to configure electronics equipment under the control of the ECS will reside in a configuration database. The database will contain two kinds of information: 1.\tConfiguration properties about devices such as hardware addresses, geographical location, and operational parameters associated with particular running modes (dynamic properties). 2.\tConnectivity between devices : this consists of describing the output and input connections of a device (static properties). The representation of these data using tables must be complete so that it can provide all the required information to the ECS and must cater for all the subsystems. The design should also guarantee a fast response time, even if a query results in a large volume of data being loaded from the database into the ECS. To fulfil these constraints, we apply the following methodology: Determine from the d...

  4. Mouse genome database 2016.

    Science.gov (United States)

    Bult, Carol J; Eppig, Janan T; Blake, Judith A; Kadin, James A; Richardson, Joel E

    2016-01-01

    The Mouse Genome Database (MGD; http://www.informatics.jax.org) is the primary community model organism database for the laboratory mouse and serves as the source for key biological reference data related to mouse genes, gene functions, phenotypes and disease models with a strong emphasis on the relationship of these data to human biology and disease. As the cost of genome-scale sequencing continues to decrease and new technologies for genome editing become widely adopted, the laboratory mouse is more important than ever as a model system for understanding the biological significance of human genetic variation and for advancing the basic research needed to support the emergence of genome-guided precision medicine. Recent enhancements to MGD include new graphical summaries of biological annotations for mouse genes, support for mobile access to the database, tools to support the annotation and analysis of sets of genes, and expanded support for comparative biology through the expansion of homology data.

  5. Database Application Schema Forensics

    Directory of Open Access Journals (Sweden)

    Hector Quintus Beyers

    2014-12-01

    Full Text Available The application schema layer of a Database Management System (DBMS can be modified to deliver results that may warrant a forensic investigation. Table structures can be corrupted by changing the metadata of a database or operators of the database can be altered to deliver incorrect results when used in queries. This paper will discuss categories of possibilities that exist to alter the application schema with some practical examples. Two forensic environments are introduced where a forensic investigation can take place in. Arguments are provided why these environments are important. Methods are presented how these environments can be achieved for the application schema layer of a DBMS. A process is proposed on how forensic evidence should be extracted from the application schema layer of a DBMS. The application schema forensic evidence identification process can be applied to a wide range of forensic settings.

  6. Towards Sensor Database Systems

    DEFF Research Database (Denmark)

    Bonnet, Philippe; Gehrke, Johannes; Seshadri, Praveen

    2001-01-01

    Sensor networks are being widely deployed for measurement, detection and surveillance applications. In these new applications, users issue long-running queries over a combination of stored data and sensor data. Most existing applications rely on a centralized system for collecting sensor data....... These systems lack flexibility because data is extracted in a predefined way; also, they do not scale to a large number of devices because large volumes of raw data are transferred regardless of the queries that are submitted. In our new concept of sensor database system, queries dictate which data is extracted...... from the sensors. In this paper, we define the concept of sensor databases mixing stored data represented as relations and sensor data represented as time series. Each long-running query formulated over a sensor database defines a persistent view, which is maintained during a given time interval. We...

  7. The Danish Melanoma Database

    DEFF Research Database (Denmark)

    Hölmich, Lisbet Rosenkrantz; Klausen, Siri; Spaun, Eva;

    2016-01-01

    AIM OF DATABASE: The aim of the database is to monitor and improve the treatment and survival of melanoma patients. STUDY POPULATION: All Danish patients with cutaneous melanoma and in situ melanomas must be registered in the Danish Melanoma Database (DMD). In 2014, 2,525 patients with invasive...... melanoma and 780 with in situ tumors were registered. The coverage is currently 93% compared with the Danish Pathology Register. MAIN VARIABLES: The main variables include demographic, clinical, and pathological characteristics, including Breslow's tumor thickness, ± ulceration, mitoses, and tumor...... quality register. The coverage is high, and the performance in the five Danish regions is quite similar due to strong adherence to guidelines provided by the Danish Melanoma Group. The list of monitored indicators is constantly expanding, and annual quality reports are issued. Several important scientific...

  8. The Danish Sarcoma Database

    DEFF Research Database (Denmark)

    Jørgensen, Peter Holmberg; Lausten, Gunnar Schwarz; Pedersen, Alma B

    2016-01-01

    AIM: The aim of the database is to gather information about sarcomas treated in Denmark in order to continuously monitor and improve the quality of sarcoma treatment in a local, a national, and an international perspective. STUDY POPULATION: Patients in Denmark diagnosed with a sarcoma, both...... skeletal and ekstraskeletal, are to be registered since 2009. MAIN VARIABLES: The database contains information about appearance of symptoms; date of receiving referral to a sarcoma center; date of first visit; whether surgery has been performed elsewhere before referral, diagnosis, and treatment; tumor...... of Diseases - tenth edition codes and TNM Classification of Malignant Tumours, and date of death (after yearly coupling to the Danish Civil Registration System). Data quality and completeness are currently secured. CONCLUSION: The Danish Sarcoma Database is population based and includes sarcomas occurring...

  9. DistiLD Database

    DEFF Research Database (Denmark)

    Palleja, Albert; Horn, Heiko; Eliasson, Sabrina

    2012-01-01

    Genome-wide association studies (GWAS) have identified thousands of single nucleotide polymorphisms (SNPs) associated with the risk of hundreds of diseases. However, there is currently no database that enables non-specialists to answer the following simple questions: which SNPs associated...... blocks, so that SNPs in LD with each other are preferentially in the same block, whereas SNPs not in LD are in different blocks. By projecting SNPs and genes onto LD blocks, the DistiLD database aims to increase usage of existing GWAS results by making it easy to query and visualize disease......-associated SNPs and genes in their chromosomal context. The database is available at http://distild.jensenlab.org/....

  10. Harmonization of Databases

    DEFF Research Database (Denmark)

    Charlifue, Susan; Tate, Denise; Biering-Sorensen, Fin

    2016-01-01

    The objectives of this article are to (1) provide an overview of existing spinal cord injury (SCI) clinical research databases-their purposes, characteristics, and accessibility to users; and (2) present a vision for future collaborations required for cross-cutting research in SCI. This vision...... strengths and weaknesses. Efforts to provide a uniform approach to data collection are also reviewed. The databases reviewed offer different approaches to capture important clinical information on SCI. They vary on size, purpose, data points, inclusion of standard outcomes, and technical requirements. Each...... highlights the need for validated and relevant data for longitudinal clinical trials and observational and epidemiologic SCI-related studies. Three existing SCI clinical research databases/registries are reviewed and summarized with regard to current formats, collection methods, and uses, including major...

  11. Danish Gynecological Cancer Database

    DEFF Research Database (Denmark)

    Sørensen, Sarah Mejer; Bjørn, Signe Frahm; Jochumsen, Kirsten Marie;

    2016-01-01

    AIM OF DATABASE: The Danish Gynecological Cancer Database (DGCD) is a nationwide clinical cancer database and its aim is to monitor the treatment quality of Danish gynecological cancer patients, and to generate data for scientific purposes. DGCD also records detailed data on the diagnostic measures...... for gynecological cancer. STUDY POPULATION: DGCD was initiated January 1, 2005, and includes all patients treated at Danish hospitals for cancer of the ovaries, peritoneum, fallopian tubes, cervix, vulva, vagina, and uterus, including rare histological types. MAIN VARIABLES: DGCD data are organized within separate...... Danish personal identification number (CPR number). DESCRIPTIVE DATA: Data from DGCD and registers are available online in the Statistical Analysis Software portal. The DGCD forms cover almost all possible clinical variables used to describe gynecological cancer courses. The only limitation...

  12. Medical database security evaluation.

    Science.gov (United States)

    Pangalos, G J

    1993-01-01

    Users of medical information systems need confidence in the security of the system they are using. They also need a method to evaluate and compare its security capabilities. Every system has its own requirements for maintaining confidentiality, integrity and availability. In order to meet these requirements a number of security functions must be specified covering areas such as access control, auditing, error recovery, etc. Appropriate confidence in these functions is also required. The 'trust' in trusted computer systems rests on their ability to prove that their secure mechanisms work as advertised and cannot be disabled or diverted. The general framework and requirements for medical database security and a number of parameters of the evaluation problem are presented and discussed. The problem of database security evaluation is then discussed, and a number of specific proposals are presented, based on a number of existing medical database security systems.

  13. The Danish Sarcoma Database

    Directory of Open Access Journals (Sweden)

    Jorgensen PH

    2016-10-01

    Full Text Available Peter Holmberg Jørgensen,1 Gunnar Schwarz Lausten,2 Alma B Pedersen3 1Tumor Section, Department of Orthopedic Surgery, Aarhus University Hospital, Aarhus, 2Tumor Section, Department of Orthopedic Surgery, Rigshospitalet, Copenhagen, 3Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark Aim: The aim of the database is to gather information about sarcomas treated in Denmark in order to continuously monitor and improve the quality of sarcoma treatment in a local, a national, and an international perspective. Study population: Patients in Denmark diagnosed with a sarcoma, both skeletal and ekstraskeletal, are to be registered since 2009. Main variables: The database contains information about appearance of symptoms; date of receiving referral to a sarcoma center; date of first visit; whether surgery has been performed elsewhere before referral, diagnosis, and treatment; tumor characteristics such as location, size, malignancy grade, and growth pattern; details on treatment (kind of surgery, amount of radiation therapy, type and duration of chemotherapy; complications of treatment; local recurrence and metastases; and comorbidity. In addition, several quality indicators are registered in order to measure the quality of care provided by the hospitals and make comparisons between hospitals and with international standards. Descriptive data: Demographic patient-specific data such as age, sex, region of living, comorbidity, World Health Organization's International Classification of Diseases – tenth edition codes and TNM Classification of Malignant Tumours, and date of death (after yearly coupling to the Danish Civil Registration System. Data quality and completeness are currently secured. Conclusion: The Danish Sarcoma Database is population based and includes sarcomas occurring in Denmark since 2009. It is a valuable tool for monitoring sarcoma incidence and quality of treatment and its improvement, postoperative

  14. Database Description - KOME | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available [ Credits ] BLAST Search Image Search Home About Archive Update History Contact us KOME Database... Description General information of database Database name Knowledge-based Oryza Molecular biol...baraki 305-8602, Japan National Institute of Agrobiological Sciences Plant Genome Research Unit Shoshi Kikuchi E-mail : Database... classification Plant databases - Rice Organism Taxonomy Name: Oryza sativa Taxonomy ID: 4530 Database...A clones that were completely sequenced in the Rice full-length cDNA project is shown in the database. The f

  15. Database Description - GETDB | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us GETDB Database Description General information of database Database name GETDB Alternative n...ame Gal4 Enhancer Trap Insertion Database DOI 10.18908/lsdba.nbdc00236-000 Creator Creator Name: Shigeo Haya... Chuo-ku, Kobe 650-0047 Tel: +81-78-306-3185 FAX: +81-78-306-3183 E-mail: Database classification Expression... Invertebrate genome database Organism Taxonomy Name: Drosophila melanogaster Taxonomy ID: 7227 Database des...cription About 4,600 insertion lines of enhancer trap lines based on the Gal4-UAS

  16. Meditation Experience Predicts Introspective Accuracy

    Science.gov (United States)

    Fox, Kieran C. R.; Zakarauskas, Pierre; Dixon, Matt; Ellamil, Melissa; Thompson, Evan; Christoff, Kalina

    2012-01-01

    The accuracy of subjective reports, especially those involving introspection of one's own internal processes, remains unclear, and research has demonstrated large individual differences in introspective accuracy. It has been hypothesized that introspective accuracy may be heightened in persons who engage in meditation practices, due to the highly introspective nature of such practices. We undertook a preliminary exploration of this hypothesis, examining introspective accuracy in a cross-section of meditation practitioners (1–15,000 hrs experience). Introspective accuracy was assessed by comparing subjective reports of tactile sensitivity for each of 20 body regions during a ‘body-scanning’ meditation with averaged, objective measures of tactile sensitivity (mean size of body representation area in primary somatosensory cortex; two-point discrimination threshold) as reported in prior research. Expert meditators showed significantly better introspective accuracy than novices; overall meditation experience also significantly predicted individual introspective accuracy. These results suggest that long-term meditators provide more accurate introspective reports than novices. PMID:23049790

  17. C# Database Basics

    CERN Document Server

    Schmalz, Michael

    2012-01-01

    Working with data and databases in C# certainly can be daunting if you're coming from VB6, VBA, or Access. With this hands-on guide, you'll shorten the learning curve considerably as you master accessing, adding, updating, and deleting data with C#-basic skills you need if you intend to program with this language. No previous knowledge of C# is necessary. By following the examples in this book, you'll learn how to tackle several database tasks in C#, such as working with SQL Server, building data entry forms, and using data in a web service. The book's code samples will help you get started

  18. Rett networked database

    DEFF Research Database (Denmark)

    Grillo, Elisa; Villard, Laurent; Clarke, Angus

    2012-01-01

    underlie some (usually variant) cases. There is only limited correlation between genotype and phenotype. The Rett Networked Database (http://www.rettdatabasenetwork.org/) has been established to share clinical and genetic information. Through an "adaptor" process of data harmonization, a set of 293...... clinical items and 16 genetic items was generated; 62 clinical and 7 genetic items constitute the core dataset; 23 clinical items contain longitudinal information. The database contains information on 1838 patients from 11 countries (December 2011), with or without mutations in known genes. These numbers...

  19. MARKS ON ART database

    DEFF Research Database (Denmark)

    van Vlierden, Marieke; Wadum, Jørgen; Wolters, Margreet

    2016-01-01

    Mestermærker, monogrammer og kvalitetsmærker findes ofte præget eller stemplet på kunstværker fra 1300-1700. En illustreret database med denne typer mræker er under etablering på Nederlands Kunsthistoriske Institut (RKD) i Den Haag.......Mestermærker, monogrammer og kvalitetsmærker findes ofte præget eller stemplet på kunstværker fra 1300-1700. En illustreret database med denne typer mræker er under etablering på Nederlands Kunsthistoriske Institut (RKD) i Den Haag....

  20. The CATH database

    Directory of Open Access Journals (Sweden)

    Knudsen Michael

    2010-02-01

    Full Text Available Abstract The CATH database provides hierarchical classification of protein domains based on their folding patterns. Domains are obtained from protein structures deposited in the Protein Data Bank and both domain identification and subsequent classification use manual as well as automated procedures. The accompanying website http://www.cathdb.info provides an easy-to-use entry to the classification, allowing for both browsing and downloading of data. Here, we give a brief review of the database, its corresponding website and some related tools.

  1. Empathic accuracy for happiness in the daily lives of older couples: Fluid cognitive performance predicts pattern accuracy among men.

    Science.gov (United States)

    Hülür, Gizem; Hoppmann, Christiane A; Rauers, Antje; Schade, Hannah; Ram, Nilam; Gerstorf, Denis

    2016-08-01

    Correctly identifying other's emotional states is a central cognitive component of empathy. We examined the role of fluid cognitive performance for empathic accuracy for happiness in the daily lives of 86 older couples (mean relationship length = 45 years; mean age = 75 years) on up to 42 occasions over 7 consecutive days. Men performing better on the Digit Symbol test were more accurate in identifying ups and downs of their partner's happiness. A similar association was not found for women. We discuss the potential role of fluid cognitive performance and other individual, partner, and situation characteristics for empathic accuracy. (PsycINFO Database Record

  2. Database for Simulation of Electron Spectra for Surface Analysis (SESSA)Database for Simulation of Electron Spectra for Surface Analysis (SESSA)

    Science.gov (United States)

    SRD 100 Database for Simulation of Electron Spectra for Surface Analysis (SESSA)Database for Simulation of Electron Spectra for Surface Analysis (SESSA) (PC database for purchase)   This database has been designed to facilitate quantitative interpretation of Auger-electron and X-ray photoelectron spectra and to improve the accuracy of quantitation in routine analysis. The database contains all physical data needed to perform quantitative interpretation of an electron spectrum for a thin-film specimen of given composition. A simulation module provides an estimate of peak intensities as well as the energy and angular distributions of the emitted electron flux.

  3. Database trial impact on graduate nursing comprehensive exams.

    Science.gov (United States)

    Pionke, Katharine; Huckstadt, Alicia

    2015-10-01

    While the authors were doing a test period of databases, the question of whether or not databases affect outcomes of graduate nursing comprehensive examinations came up. This study explored that question through using citation analysis of exams that were taken during a database trial and exams that were not. The findings showed no difference in examination pass/fail rates. While the pass/fail rates did not change, a great deal was learned in terms of citation accuracy and types of materials that students used, leading to discussions about changing how citation and plagiarism awareness were taught.

  4. Database management systems understanding and applying database technology

    CERN Document Server

    Gorman, Michael M

    1991-01-01

    Database Management Systems: Understanding and Applying Database Technology focuses on the processes, methodologies, techniques, and approaches involved in database management systems (DBMSs).The book first takes a look at ANSI database standards and DBMS applications and components. Discussion focus on application components and DBMS components, implementing the dynamic relationship application, problems and benefits of dynamic relationship DBMSs, nature of a dynamic relationship application, ANSI/NDL, and DBMS standards. The manuscript then ponders on logical database, interrogation, and phy

  5. BioWarehouse: a bioinformatics database warehouse toolkit

    Directory of Open Access Journals (Sweden)

    Stringer-Calvert David WJ

    2006-03-01

    Full Text Available Abstract Background This article addresses the problem of interoperation of heterogeneous bioinformatics databases. Results We introduce BioWarehouse, an open source toolkit for constructing bioinformatics database warehouses using the MySQL and Oracle relational database managers. BioWarehouse integrates its component databases into a common representational framework within a single database management system, thus enabling multi-database queries using the Structured Query Language (SQL but also facilitating a variety of database integration tasks such as comparative analysis and data mining. BioWarehouse currently supports the integration of a pathway-centric set of databases including ENZYME, KEGG, and BioCyc, and in addition the UniProt, GenBank, NCBI Taxonomy, and CMR databases, and the Gene Ontology. Loader tools, written in the C and JAVA languages, parse and load these databases into a relational database schema. The loaders also apply a degree of semantic normalization to their respective source data, decreasing semantic heterogeneity. The schema supports the following bioinformatics datatypes: chemical compounds, biochemical reactions, metabolic pathways, proteins, genes, nucleic acid sequences, features on protein and nucleic-acid sequences, organisms, organism taxonomies, and controlled vocabularies. As an application example, we applied BioWarehouse to determine the fraction of biochemically characterized enzyme activities for which no sequences exist in the public sequence databases. The answer is that no sequence exists for 36% of enzyme activities for which EC numbers have been assigned. These gaps in sequence data significantly limit the accuracy of genome annotation and metabolic pathway prediction, and are a barrier for metabolic engineering. Complex queries of this type provide examples of the value of the data warehousing approach to bioinformatics research. Conclusion BioWarehouse embodies significant progress on the

  6. MARC and Relational Databases.

    Science.gov (United States)

    Llorens, Jose; Trenor, Asuncion

    1993-01-01

    Discusses the use of MARC format in relational databases and addresses problems of incompatibilities. A solution is presented that is in accordance with Open Systems Interconnection (OSI) standards and is based on experiences at the library of the Universidad Politecnica de Valencia (Spain). (four references) (EA)

  7. NoSQL Databases

    OpenAIRE

    2014-01-01

    In this document, I present the main notions of NoSQL databases and compare four selected products (Riak, MongoDB, Cassandra, Neo4J) according to their capabilities with respect to consistency, availability, and partition tolerance, as well as performance. I also propose a few criteria for selecting the right tool for the right situation.

  8. Dansk kolorektal Cancer Database

    DEFF Research Database (Denmark)

    Harling, Henrik; Nickelsen, Thomas

    2005-01-01

    The Danish Colorectal Cancer Database was established in 1994 with the purpose of monitoring whether diagnostic and surgical principles specified in the evidence-based national guidelines of good clinical practice were followed. Twelve clinical indicators have been listed by the Danish Colorectal...

  9. Dutch Vegetation Database (LVD)

    NARCIS (Netherlands)

    Hennekens, S.M.

    2011-01-01

    The Dutch Vegetation Database (LVD) hosts information on all plant communities in the Netherlands. This substantial archive consists of over 600.000 recent and historic vegetation descriptions. The data provide information on more than 85 years of vegetation recording in various habitats covering te

  10. Database Programming Languages

    DEFF Research Database (Denmark)

    This volume contains the proceedings of the 11th International Symposium on Database Programming Languages (DBPL 2007), held in Vienna, Austria, on September 23-24, 2007. DBPL 2007 was one of 15 meetings co-located with VLBD (the International Conference on Very Large Data Bases). DBPL continues...

  11. Database for West Africa

    African Journals Online (AJOL)

    Such database can prove an invaluable source of information for a wide range of agricultural and ... national soil classification systems around the world ... West African Journal of Appl ied Ecology, vol. .... SDB FAO-ISRIC English, French, Spanish Morphology and analytical ..... Furthermore, it will enhance the state of soil.

  12. Food composition databases

    Science.gov (United States)

    Food composition is the determination of what is in the foods we eat and is the critical bridge between nutrition, health promotion and disease prevention and food production. Compilation of data into useable databases is essential to the development of dietary guidance for individuals and populat...

  13. The Ribosomal Database Project

    Science.gov (United States)

    Olsen, G. J.; Overbeek, R.; Larsen, N.; Marsh, T. L.; McCaughey, M. J.; Maciukenas, M. A.; Kuan, W. M.; Macke, T. J.; Xing, Y.; Woese, C. R.

    1992-01-01

    The Ribosomal Database Project (RDP) complies ribosomal sequences and related data, and redistributes them in aligned and phylogenetically ordered form to its user community. It also offers various software packages for handling, analyzing and displaying sequences. In addition, the RDP offers (or will offer) certain analytic services. At present the project is in an intermediate stage of development.

  14. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  15. Database on wind characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, K.S. [The Technical Univ. of Denmark (Denmark); Courtney, M.S. [Risoe National Lab., (Denmark)

    1999-08-01

    The organisations that participated in the project consists of five research organisations: MIUU (Sweden), ECN (The Netherlands), CRES (Greece), DTU (Denmark), Risoe (Denmark) and one wind turbine manufacturer: Vestas Wind System A/S (Denmark). The overall goal was to build a database consisting of a large number of wind speed time series and create tools for efficiently searching through the data to select interesting data. The project resulted in a database located at DTU, Denmark with online access through the Internet. The database contains more than 50.000 hours of measured wind speed measurements. A wide range of wind climates and terrain types are represented with significant amounts of time series. Data have been chosen selectively with a deliberate over-representation of high wind and complex terrain cases. This makes the database ideal for wind turbine design needs but completely unsuitable for resource studies. Diversity has also been an important aim and this is realised with data from a large range of terrain types; everything from offshore to mountain, from Norway to Greece. (EHS)

  16. Databases and data mining

    Science.gov (United States)

    Over the course of the past decade, the breadth of information that is made available through online resources for plant biology has increased astronomically, as have the interconnectedness among databases, online tools, and methods of data acquisition and analysis. For maize researchers, the numbe...

  17. Test expectancy affects metacomprehension accuracy.

    Science.gov (United States)

    Thiede, Keith W; Wiley, Jennifer; Griffin, Thomas D

    2011-06-01

    Theory suggests that the accuracy of metacognitive monitoring is affected by the cues used to judge learning. Researchers have improved monitoring accuracy by directing attention to more appropriate cues; however, this is the first study to more directly point students to more appropriate cues using instructions regarding tests and practice tests. The purpose of the present study was to examine whether the accuracy metacognitive monitoring was affected by the nature of the test expected. Students (N= 59) were randomly assigned to one of two test expectancy groups (memory vs. inference). Then after reading texts, judging learning, completed both memory and inference tests. Test performance and monitoring accuracy were superior when students received the kind of test they had been led to expect rather than the unexpected test. Tests influence students' perceptions of what constitutes learning. Our findings suggest that this could affect how students prepare for tests and how they monitoring their own learning. ©2010 The British Psychological Society.

  18. The AMMA database

    Science.gov (United States)

    Boichard, Jean-Luc; Brissebrat, Guillaume; Cloche, Sophie; Eymard, Laurence; Fleury, Laurence; Mastrorillo, Laurence; Moulaye, Oumarou; Ramage, Karim

    2010-05-01

    The AMMA project includes aircraft, ground-based and ocean measurements, an intensive use of satellite data and diverse modelling studies. Therefore, the AMMA database aims at storing a great amount and a large variety of data, and at providing the data as rapidly and safely as possible to the AMMA research community. In order to stimulate the exchange of information and collaboration between researchers from different disciplines or using different tools, the database provides a detailed description of the products and uses standardized formats. The AMMA database contains: - AMMA field campaigns datasets; - historical data in West Africa from 1850 (operational networks and previous scientific programs); - satellite products from past and future satellites, (re-)mapped on a regular latitude/longitude grid and stored in NetCDF format (CF Convention); - model outputs from atmosphere or ocean operational (re-)analysis and forecasts, and from research simulations. The outputs are processed as the satellite products are. Before accessing the data, any user has to sign the AMMA data and publication policy. This chart only covers the use of data in the framework of scientific objectives and categorically excludes the redistribution of data to third parties and the usage for commercial applications. Some collaboration between data producers and users, and the mention of the AMMA project in any publication is also required. The AMMA database and the associated on-line tools have been fully developed and are managed by two teams in France (IPSL Database Centre, Paris and OMP, Toulouse). Users can access data of both data centres using an unique web portal. This website is composed of different modules : - Registration: forms to register, read and sign the data use chart when an user visits for the first time - Data access interface: friendly tool allowing to build a data extraction request by selecting various criteria like location, time, parameters... The request can

  19. DataBase on demand

    CERN Document Server

    Aparicio, Ruben Gaspar; Coterillo Coz, I

    2012-01-01

    At CERN a number of key database applications are running on user-managed MySQL database services. The database on demand project was born out of an idea to provide the CERN user community with an environment to develop and run database services outside of the actual centralised Oracle based database services. The Database on Demand (DBoD) empowers the user to perform certain actions that had been traditionally done by database administrators, DBA's, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently open community version of MySQL and single instance Oracle database server. This article describes a technology approach to face this challenge, a service level agreement, the SLA that the project provides, and an evolution of possible scenarios.

  20. DataBase on Demand

    Science.gov (United States)

    Gaspar Aparicio, R.; Gomez, D.; Coterillo Coz, I.; Wojcik, D.

    2012-12-01

    At CERN a number of key database applications are running on user-managed MySQL database services. The database on demand project was born out of an idea to provide the CERN user community with an environment to develop and run database services outside of the actual centralised Oracle based database services. The Database on Demand (DBoD) empowers the user to perform certain actions that had been traditionally done by database administrators, DBA's, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently open community version of MySQL and single instance Oracle database server. This article describes a technology approach to face this challenge, a service level agreement, the SLA that the project provides, and an evolution of possible scenarios.

  1. Process Analysis Via Accuracy Control

    Science.gov (United States)

    1982-02-01

    0 1 4 3 NDARDS THE NATIONAL February 1982 Process Analysis Via Accuracy Control RESEARCH PROG RAM U.S. DEPARTMENT OF TRANSPORTATION Maritime...SUBTITLE Process Analysis Via Accuracy Control 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e...examples are contained in Appendix C. Included, are examples of how “A/C” process - analysis leads to design improvement and how a change in sequence can

  2. Social Power Increases Interoceptive Accuracy

    Directory of Open Access Journals (Sweden)

    Mehrad Moeini-Jazani

    2017-08-01

    Full Text Available Building on recent psychological research showing that power increases self-focused attention, we propose that having power increases accuracy in perception of bodily signals, a phenomenon known as interoceptive accuracy. Consistent with our proposition, participants in a high-power experimental condition outperformed those in the control and low-power conditions in the Schandry heartbeat-detection task. We demonstrate that the effect of power on interoceptive accuracy is not explained by participants’ physiological arousal, affective state, or general intention for accuracy. Rather, consistent with our reasoning that experiencing power shifts attentional resources inward, we show that the effect of power on interoceptive accuracy is dependent on individuals’ chronic tendency to focus on their internal sensations. Moreover, we demonstrate that individuals’ chronic sense of power also predicts interoceptive accuracy similar to, and independent of, how their situationally induced feeling of power does. We therefore provide further support on the relation between power and enhanced perception of bodily signals. Our findings offer a novel perspective–a psychophysiological account–on how power might affect judgments and behavior. We highlight and discuss some of these intriguing possibilities for future research.

  3. Hadoop NoSQL database

    OpenAIRE

    2015-01-01

    The theme of this work is database storage Hadoop Hbase. The main goal is to demonstrate the principles of its function and show the main usage. The entire text assumes that the reader is already familiar with the basic principles of NoSQL databases. The theoretical part briefly describes the basic concepts of databases then mostly covers Hadoop and its properties. This work also includes the practical part which describes how to install a database repository and illustrates basic database op...

  4. The Database State Machine Approach

    OpenAIRE

    1999-01-01

    Database replication protocols have historically been built on top of distributed database systems, and have consequently been designed and implemented using distributed transactional mechanisms, such as atomic commitment. We present the Database State Machine approach, a new way to deal with database replication in a cluster of servers. This approach relies on a powerful atomic broadcast primitive to propagate transactions between database servers, and alleviates the need for atomic comm...

  5. Interim report on the meteorological database

    Energy Technology Data Exchange (ETDEWEB)

    Stage, S.A.; Ramsdell, J.V.; Simonen, C.A.; Burk, K.W.

    1993-01-01

    The Hanford Environmental Dose Reconstruction (HEDR) Project is estimating radiation doses that individuals may have received from operations at Hanford from 1944 to the present. An independent Technical Steering Panel (TSP) directs the project, which is being conducted by the Battelle, Pacific Northwest Laboratories in Richland, Washington. The goals of HEDR, as approved by the TSP, include dose estimates and determination of confidence ranges for these estimates. This letter report describes the current status of the meteorological database. The report defines the meteorological data available for use in climate model calculations, describes the data collection procedures and the preparation and control of the meteorological database. This report also provides an initial assessment of the data quality. The available meteorological data are adequate for atmospheric calculations. Initial checks of the data indicate the data entry accuracy meets the data quality objectives.

  6. Very large database of lipids: rationale and design.

    Science.gov (United States)

    Martin, Seth S; Blaha, Michael J; Toth, Peter P; Joshi, Parag H; McEvoy, John W; Ahmed, Haitham M; Elshazly, Mohamed B; Swiger, Kristopher J; Michos, Erin D; Kwiterovich, Peter O; Kulkarni, Krishnaji R; Chimera, Joseph; Cannon, Christopher P; Blumenthal, Roger S; Jones, Steven R

    2013-11-01

    Blood lipids have major cardiovascular and public health implications. Lipid-lowering drugs are prescribed based in part on categorization of patients into normal or abnormal lipid metabolism, yet relatively little emphasis has been placed on: (1) the accuracy of current lipid measures used in clinical practice, (2) the reliability of current categorizations of dyslipidemia states, and (3) the relationship of advanced lipid characterization to other cardiovascular disease biomarkers. To these ends, we developed the Very Large Database of Lipids (NCT01698489), an ongoing database protocol that harnesses deidentified data from the daily operations of a commercial lipid laboratory. The database includes individuals who were referred for clinical purposes for a Vertical Auto Profile (Atherotech Inc., Birmingham, AL), which directly measures cholesterol concentrations of low-density lipoprotein, very low-density lipoprotein, intermediate-density lipoprotein, high-density lipoprotein, their subclasses, and lipoprotein(a). Individual Very Large Database of Lipids studies, ranging from studies of measurement accuracy, to dyslipidemia categorization, to biomarker associations, to characterization of rare lipid disorders, are investigator-initiated and utilize peer-reviewed statistical analysis plans to address a priori hypotheses/aims. In the first database harvest (Very Large Database of Lipids 1.0) from 2009 to 2011, there were 1 340 614 adult and 10 294 pediatric patients; the adult sample had a median age of 59 years (interquartile range, 49-70 years) with even representation by sex. Lipid distributions closely matched those from the population-representative National Health and Nutrition Examination Survey. The second harvest of the database (Very Large Database of Lipids 2.0) is underway. Overall, the Very Large Database of Lipids database provides an opportunity for collaboration and new knowledge generation through careful examination of granular lipid data on

  7. CADASTRAL POSITIONING ACCURACY IMPROVEMENT: A CASE STUDY IN MALAYSIA

    Directory of Open Access Journals (Sweden)

    N. M. Hashim

    2016-09-01

    Full Text Available Cadastral map is a parcel-based information which is specifically designed to define the limitation of boundaries. In Malaysia, the cadastral map is under authority of the Department of Surveying and Mapping Malaysia (DSMM. With the growth of spatial based technology especially Geographical Information System (GIS, DSMM decided to modernize and reform its cadastral legacy datasets by generating an accurate digital based representation of cadastral parcels. These legacy databases usually are derived from paper parcel maps known as certified plan. The cadastral modernization will result in the new cadastral database no longer being based on single and static parcel paper maps, but on a global digital map. Despite the strict process of the cadastral modernization, this reform has raised unexpected queries that remain essential to be addressed. The main focus of this study is to review the issues that have been generated by this transition. The transformed cadastral database should be additionally treated to minimize inherent errors and to fit them to the new satellite based coordinate system with high positional accuracy. This review result will be applied as a foundation for investigation to study the systematic and effectiveness method for Positional Accuracy Improvement (PAI in cadastral database modernization.

  8. Cadastral Positioning Accuracy Improvement: a Case Study in Malaysia

    Science.gov (United States)

    Hashim, N. M.; Omar, A. H.; Omar, K. M.; Abdullah, N. M.; Yatim, M. H. M.

    2016-09-01

    Cadastral map is a parcel-based information which is specifically designed to define the limitation of boundaries. In Malaysia, the cadastral map is under authority of the Department of Surveying and Mapping Malaysia (DSMM). With the growth of spatial based technology especially Geographical Information System (GIS), DSMM decided to modernize and reform its cadastral legacy datasets by generating an accurate digital based representation of cadastral parcels. These legacy databases usually are derived from paper parcel maps known as certified plan. The cadastral modernization will result in the new cadastral database no longer being based on single and static parcel paper maps, but on a global digital map. Despite the strict process of the cadastral modernization, this reform has raised unexpected queries that remain essential to be addressed. The main focus of this study is to review the issues that have been generated by this transition. The transformed cadastral database should be additionally treated to minimize inherent errors and to fit them to the new satellite based coordinate system with high positional accuracy. This review result will be applied as a foundation for investigation to study the systematic and effectiveness method for Positional Accuracy Improvement (PAI) in cadastral database modernization.

  9. The Danish Melanoma Database

    Directory of Open Access Journals (Sweden)

    Hölmich Lr

    2016-10-01

    Full Text Available Lisbet Rosenkrantz Hölmich,1 Siri Klausen,2 Eva Spaun,3 Grethe Schmidt,4 Dorte Gad,5 Inge Marie Svane,6,7 Henrik Schmidt,8 Henrik Frank Lorentzen,9 Else Helene Ibfelt10 1Department of Plastic Surgery, 2Department of Pathology, Herlev-Gentofte Hospital, University of Copenhagen, Herlev, 3Institute of Pathology, Aarhus University Hospital, Aarhus, 4Department of Plastic and Reconstructive Surgery, Breast Surgery and Burns, Rigshospitalet – Glostrup, University of Copenhagen, Copenhagen, 5Department of Plastic Surgery, Odense University Hospital, Odense, 6Center for Cancer Immune Therapy, Department of Hematology, 7Department of Oncology, Herlev-Gentofte Hospital, University of Copenhagen, Herlev, 8Department of Oncology, 9Department of Dermatology, Aarhus University Hospital, Aarhus, 10Registry Support Centre (East – Epidemiology and Biostatistics, Research Centre for Prevention and Health, Glostrup – Rigshospitalet, University of Copenhagen, Glostrup, Denmark Aim of database: The aim of the database is to monitor and improve the treatment and survival of melanoma patients.Study population: All Danish patients with cutaneous melanoma and in situ melanomas must be registered in the Danish Melanoma Database (DMD. In 2014, 2,525 patients with invasive melanoma and 780 with in situ tumors were registered. The coverage is currently 93% compared with the Danish Pathology Register.Main variables: The main variables include demographic, clinical, and pathological characteristics, including Breslow’s tumor thickness, ± ulceration, mitoses, and tumor–node–metastasis stage. Information about the date of diagnosis, treatment, type of surgery, including safety margins, results of lymphoscintigraphy in patients for whom this was indicated (tumors > T1a, results of sentinel node biopsy, pathological evaluation hereof, and follow-up information, including recurrence, nature, and treatment hereof is registered. In case of death, the cause and date

  10. Database Description - DMPD | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us DMPD Database Description General information of database Database name DMPD Alternative nam...e Dynamic Macrophage Pathway CSML Database DOI 10.18908/lsdba.nbdc00558-000 Creator Creator Name: Masao Naga...ty of Tokyo 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 Tel: +81-3-5449-5615 FAX: +83-3-5449-5442 E-mail: Database...606 Taxonomy Name: Mammalia Taxonomy ID: 40674 Database description DMPD collects... pathway models of transcriptional regulation and signal transduction in CSML format for dymamic simulation base

  11. An Audit of the Irish National Intellectual Disability Database

    Science.gov (United States)

    Dodd, Philip; Craig, Sarah; Kelly, Fionnola; Guerin, Suzanne

    2010-01-01

    This study describes a national data audit of the National Intellectual Disability Database (NIDD). The NIDD is a national information system for intellectual disability (ID) for Ireland. The purpose of this audit was to assess the overall accuracy of information contained on the NIDD, as well as collecting qualitative information to support the…

  12. Building a GIS Database for Space and Facilities Management

    Science.gov (United States)

    Valcik, Nicolas A.; Huesca-Dorantes, Patricia

    2003-01-01

    Growth and technology have driven the University of Texas at Dallas (UTD) to build a geographic information system (GIS) database for its facilities and space management. This chapter reviews several issues concerning this implementation: (1) the challenges involved in implementing the system; (2) the lack of efficiency and accuracy that existed…

  13. On the proper use of mass accuracy in proteomics.

    Science.gov (United States)

    Zubarev, Roman; Mann, Matthias

    2007-03-01

    Mass measurement is the main outcome of mass spectrometry-based proteomics yet the potential of recent advances in accurate mass measurements remains largely unexploited. There is not even a clear definition of mass accuracy in the proteomics literature, and we identify at least three uses of this term: anecdotal mass accuracy, statistical mass accuracy, and the maximum mass deviation (MMD) allowed in a database search. We suggest using the second of these terms as the generic one. To make the best use of the mass precision offered by modern instruments we propose a series of simple steps involving recalibration of the data on "internal standards" contained in every proteomics data set. Each data set should be accompanied by a plot of mass errors from which the appropriate MMD can be chosen. More advanced uses of high mass accuracy include an MMD that depends on the signal abundance of each peptide. Adapting search engines to high mass accuracy in the MS/MS data is also a high priority. Proper use of high mass accuracy data can make MS-based proteomics one of the most "digital" and accurate post-genomics disciplines.

  14. Protein Model Database

    Energy Technology Data Exchange (ETDEWEB)

    Fidelis, K; Adzhubej, A; Kryshtafovych, A; Daniluk, P

    2005-02-23

    The phenomenal success of the genome sequencing projects reveals the power of completeness in revolutionizing biological science. Currently it is possible to sequence entire organisms at a time, allowing for a systemic rather than fractional view of their organization and the various genome-encoded functions. There is an international plan to move towards a similar goal in the area of protein structure. This will not be achieved by experiment alone, but rather by a combination of efforts in crystallography, NMR spectroscopy, and computational modeling. Only a small fraction of structures are expected to be identified experimentally, the remainder to be modeled. Presently there is no organized infrastructure to critically evaluate and present these data to the biological community. The goal of the Protein Model Database project is to create such infrastructure, including (1) public database of theoretically derived protein structures; (2) reliable annotation of protein model quality, (3) novel structure analysis tools, and (4) access to the highest quality modeling techniques available.

  15. Search Databases and Statistics

    DEFF Research Database (Denmark)

    Refsgaard, Jan C; Munk, Stephanie; Jensen, Lars J

    2016-01-01

    the vast amounts of raw data. This task is tackled by computational tools implementing algorithms that match the experimental data to databases, providing the user with lists for downstream analysis. Several platforms for such automated interpretation of mass spectrometric data have been developed, each...... having strengths and weaknesses that must be considered for the individual needs. These are reviewed in this chapter. Equally critical for generating highly confident output datasets is the application of sound statistical criteria to limit the inclusion of incorrect peptide identifications from database...... searches. Additionally, careful filtering and use of appropriate statistical tests on the output datasets affects the quality of all downstream analyses and interpretation of the data. Our considerations and general practices on these aspects of phosphoproteomics data processing are presented here....

  16. Geologic Field Database

    Directory of Open Access Journals (Sweden)

    Katarina Hribernik

    2002-12-01

    Full Text Available The purpose of the paper is to present the field data relational database, which was compiled from data, gathered during thirty years of fieldwork on the Basic Geologic Map of Slovenia in scale1:100.000. The database was created using MS Access software. The MS Access environment ensures its stability and effective operation despite changing, searching, and updating the data. It also enables faster and easier user-friendly access to the field data. Last but not least, in the long-term, with the data transferred into the GISenvironment, it will provide the basis for the sound geologic information system that will satisfy a broad spectrum of geologists’ needs.

  17. ARTI Refrigerant Database

    Energy Technology Data Exchange (ETDEWEB)

    Calm, J.M.

    1992-11-09

    The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R- 717 (ammonia), ethers, and others as well as azeotropic and zeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents on compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. A computerized version is available that includes retrieval software.

  18. The DIPPR® databases

    Science.gov (United States)

    Thomson, G. H.

    1996-01-01

    The Design Institute for Physical Property Data® (DIPPR), one of the Sponsored Research groups of the American Institute of Chemical Engineers (AIChE), has been in existence for 15 years and has supported a total of 14 projects, some completed, some ongoing. Four of these projects are “database” projects for which the primary product is a database of carefully evaluated property data. These projects are Data Compilation; Evaluated Data on Mixtures; Environmental, Safety, and Health Data Compilation; and Difusivities and Thermal Properties of Polymer Solutions. This paper lists the existing DIPPR projects; discusses DIPPR's structure and modes of dissemination of results; describes DIPPR's supporters and its unique characteristics; and finally, discusses the origin, nature, and content of the four database projects.

  19. A global land-cover validation data set, II: augmenting a stratified sampling design to estimate accuracy by region and land-cover class

    NARCIS (Netherlands)

    Stehman, S.; Olofsson, P.; Woodcock, C.; Herold, M.; Friedl, M.A.

    2012-01-01

    A global validation database that can be used to assess the accuracy of multiple global and regional land-cover maps would yield significant cost savings and enhance comparisons of accuracy of different maps. Because the global validation database should expand over time as new validation data are c

  20. What is a lexicographical database?

    DEFF Research Database (Denmark)

    Bergenholtz, Henning; Skovgård Nielsen, Jesper

    2013-01-01

    project. Such cooperation will reach the highest level of success if the lexicographer has at least a basic knowledge of the topic presented in this paper: What is a database? This type of knowledge is also needed when the lexicographer describes an ongoing or a finished project. In this article, we......50 years ago, no lexicographer used a database in the work process. Today, almost all dictionary projects incorporate databases. In our opinion, the optimal lexicographical database should be planned in cooperation between a lexicographer and a database specialist in each specific lexicographic...... provide the description of this type of cooperation, using the most important theoretical terms relevant in the planning of a database. It will be made clear that a lexicographical database is like any other database. The only difference is that an optimal lexicographical database is constructed to fulfil...