WorldWideScience

Sample records for external marker tracking

  1. Two-dimensional radial laser scanning for circular marker detection and external mobile robot tracking.

    Science.gov (United States)

    Teixidó, Mercè; Pallejà, Tomàs; Font, Davinia; Tresanchez, Marcel; Moreno, Javier; Palacín, Jordi

    2012-11-28

    This paper presents the use of an external fixed two-dimensional laser scanner to detect cylindrical targets attached to moving devices, such as a mobile robot. This proposal is based on the detection of circular markers in the raw data provided by the laser scanner by applying an algorithm for outlier avoidance and a least-squares circular fitting. Some experiments have been developed to empirically validate the proposal with different cylindrical targets in order to estimate the location and tracking errors achieved, which are generally less than 20 mm in the area covered by the laser sensor. As a result of the validation experiments, several error maps have been obtained in order to give an estimate of the uncertainty of any location computed. This proposal has been validated with a medium-sized mobile robot with an attached cylindrical target (diameter 200 mm). The trajectory of the mobile robot was estimated with an average location error of less than 15 mm, and the real location error in each individual circular fitting was similar to the error estimated with the obtained error maps. The radial area covered in this validation experiment was up to 10 m, a value that depends on the radius of the cylindrical target and the radial density of the distance range points provided by the laser scanner but this area can be increased by combining the information of additional external laser scanners.

  2. Two-Dimensional Radial Laser Scanning for Circular Marker Detection and External Mobile Robot Tracking

    Directory of Open Access Journals (Sweden)

    Jordi Palacín

    2012-11-01

    Full Text Available This paper presents the use of an external fixed two-dimensional laser scanner to detect cylindrical targets attached to moving devices, such as a mobile robot. This proposal is based on the detection of circular markers in the raw data provided by the laser scanner by applying an algorithm for outlier avoidance and a least-squares circular fitting. Some experiments have been developed to empirically validate the proposal with different cylindrical targets in order to estimate the location and tracking errors achieved, which are generally less than 20 mm in the area covered by the laser sensor. As a result of the validation experiments, several error maps have been obtained in order to give an estimate of the uncertainty of any location computed. This proposal has been validated with a medium-sized mobile robot with an attached cylindrical target (diameter 200 mm. The trajectory of the mobile robot was estimated with an average location error of less than 15 mm, and the real location error in each individual circular fitting was similar to the error estimated with the obtained error maps. The radial area covered in this validation experiment was up to 10 m, a value that depends on the radius of the cylindrical target and the radial density of the distance range points provided by the laser scanner but this area can be increased by combining the information of additional external laser scanners.

  3. Passive markers for tracking surgical instruments in real-time 3-D ultrasound imaging.

    Science.gov (United States)

    Stoll, Jeffrey; Ren, Hongliang; Dupont, Pierre E

    2012-03-01

    A family of passive echogenic markers is presented by which the position and orientation of a surgical instrument can be determined in a 3-D ultrasound volume, using simple image processing. Markers are attached near the distal end of the instrument so that they appear in the ultrasound volume along with the instrument tip. They are detected and measured within the ultrasound image, thus requiring no external tracking device. This approach facilitates imaging instruments and tissue simultaneously in ultrasound-guided interventions. Marker-based estimates of instrument pose can be used in augmented reality displays or for image-based servoing. Design principles for marker shapes are presented that ensure imaging system and measurement uniqueness constraints are met. An error analysis is included that can be used to guide marker design and which also establishes a lower bound on measurement uncertainty. Finally, examples of marker measurement and tracking algorithms are presented along with experimental validation of the concepts.

  4. Markerless monocular tracking system for guided external eye surgery.

    Science.gov (United States)

    Monserrat, C; Rupérez, M J; Alcañiz, M; Mataix, J

    2014-12-01

    This paper presents a novel markerless monocular tracking system aimed at guiding ophthalmologists during external eye surgery. This new tracking system performs a very accurate tracking of the eye by detecting invariant points using only textures that are present in the sclera, i.e., without using traditional features like the pupil and/or cornea reflections, which remain partially or totally occluded in most surgeries. Two known algorithms that compute invariant points and correspondences between pairs of images were implemented in our system: Scalable Invariant Feature Transforms (SIFT) and Speed Up Robust Features (SURF). The results of experiments performed on phantom eyes show that, with either algorithm, the developed system tracks a sphere at a 360° rotation angle with an error that is lower than 0.5%. Some experiments have also been carried out on images of real eyes showing promising behavior of the system in the presence of blood or surgical instruments during real eye surgery.

  5. Standardization of tumor markers - priorities identified through external quality assessment.

    Science.gov (United States)

    Sturgeon, Catharine

    2016-01-01

    Tumor markers are often heterogeneous substances that may be present in elevated concentrations in the serum of cancer patients. Typically measured by immunoassay, they contribute to clinical management, particularly in screening, case-finding, prognostic assessment, and post-treatment monitoring. Data both from external quality assessment (EQA) schemes and clinical studies demonstrate significant variation in tumor marker results obtained for the same specimen using different methods. Between-method between-laboratory coefficients of variation (CV) reported by EQA schemes generally reflect the complexity of the measurand, ranging from 25% for the complex mucinous cancer antigen 19-9 (CA19-9). Improving the standardization of tumor marker measurements is particularly important for three reasons. The primary use of tumor markers is in monitoring cancer patients over long periods of time. Clinical interpretation of trends may consequently be affected if results are obtained in different laboratories using different methods or if a laboratory has to change method. Differences in results may have major implications for adoption of area-wide decision cut-offs and make implementation of these difficult. Method-related differences also make it difficult to compare clinical studies. Improving comparability of tumor marker results requires broad international agreement about which molecular forms of the measurand have clinical utility, identifying and adopting pure molecular forms as calibrants, and defining antibody specificities for their optimal detection. These aims have been achieved to varying extents for the most frequently measured serum tumor markers as described in this paper.

  6. Natural tags and markers for tracking and identifying fish

    Directory of Open Access Journals (Sweden)

    Steven Campana

    2015-12-01

    Full Text Available A winning feature of naturally-induced fish tags is their simultaneous appearance on the entire group or population, at no expense to the researcher. The challenge then becomes the search for a marker that is sufficiently distinct that it will allow clear identification of the group of interest. Elemental and isotopic fingerprints, genetic markers, growth patterns recorded in otoliths, and parasites are all examples of natural tags with demonstrated success in identifying and tracking sub-populations, groups and even individuals of teleost fishes. Far less explored are similar applications involving sharks and crustaceans such as lobsters, yet many of the same powerful tracking and identification applications appear to exist for these animals as well. In this talk, I will briefly review some of the established natural tags with proven track records for monitoring the movement of aquatic organisms, before exploring some exciting new possibilities.

  7. Analisis Penggunaan Marker Tracking Pada Augmented Reality Huruf Hijaiyah

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    Meyti Eka Apriyani

    2016-05-01

    Full Text Available Teknologi augmented reality berdasarkan metode pelacakan (tracking  terbagi menjadi dua yaitu marker based tracking dan markerless. Kedua metode ini memiliki persamaan yaitu dipengaruhi oleh jarak pendeteksian dan intensitas cahaya dalam keberhasilannya memunculkan suatu objek. Akan tetapi belum diketahui berapa jarak yang tepat dan kondisi intensitas cahaya yang ideal bagi kedua metode tersebut. Penelitian ini diusulkan untuk menganalisis pengaruh jarak pendeteksian serta integritas cahaya terhadap metode marker based tracking dan markerless. Variasi jarak yang digunakan adalah 5cm, 10cm, 20cm, 30cm, 40cm, 50cm, dan 80cm sebagai sub indikator jarak pendeteksian kemudian untuk mendapatkan variasi besarnya intensitas cahaya digunakan sumber cahaya matahari, lampu berwarna kuning, merah, hijau, biru, dan putih (terang. Metode pengujian yang digunakan yaitu menentukan jarak minimum dan jarak maksimum pendeteksian serta menentukan besarnya intensitas cahaya untuk memunculkan  suatu objek. Hasil pengujian ini adalah jarak minimum dan maksimum pendeteksian serta intensitas cahaya yang didapatkan untuk kedua metode yang diusulkan yaitu marker based tracking memiliki rata-rata jarak minimum 7.5 cm dan maksimum 80.5 cm. Sedangkan markerless rata-rata jarak minimum 3.8 cm dan maksimum 300 cm. Sistem dapat memunculkan objek pada intensitas 97 lux -1605 lux

  8. Molecular Imaging Markers to Track Huntington’s Disease Pathology

    Science.gov (United States)

    Wilson, Heather; De Micco, Rosa; Niccolini, Flavia; Politis, Marios

    2017-01-01

    Huntington’s disease (HD) is a progressive, monogenic dominant neurodegenerative disorder caused by repeat expansion mutation in the huntingtin gene. The accumulation of mutant huntingtin protein, forming intranuclear inclusions, subsequently leads to degeneration of medium spiny neurons in the striatum and cortical areas. Genetic testing can identify HD gene carriers before individuals develop overt cognitive, psychiatric, and chorea symptoms. Thus, HD gene carriers can be studied in premanifest stages to understand and track the evolution of HD pathology. While advances have been made, the precise pathophysiological mechanisms underlying HD are unclear. Magnetic resonance imaging (MRI) and positron emission tomography (PET) have been employed to understand HD pathology in presymptomatic and symptomatic disease stages. PET imaging uses radioactive tracers to detect specific changes, at a molecular level, which could be used as markers of HD progression and to monitor response to therapeutic treatments for HD gene expansion carriers (HDGECs). This review focuses on available PET techniques, employed in cross-sectional and longitudinal human studies, as biomarkers for HD, and highlights future potential PET targets. PET studies have assessed changes in postsynaptic dopaminergic receptors, brain metabolism, microglial activation, and recently phosphodiesterase 10A (PDE10A) as markers to track HD progression. Alterations in PDE10A expression are the earliest biochemical change identified in HD gene carriers up to 43 years before predicted symptomatic onset. Thus, PDE10A expression could be a promising marker to track HD progression from early premanifest disease stages. Other PET targets which have been less well investigated as biomarkers include cannabinoid, adenosine, and GABA receptors. Future longitudinal studies are required to fully validate these PET biomarkers for use to track disease progression from far-onset premanifest to manifest HD stages. PET

  9. Molecular Imaging Markers to Track Huntington's Disease Pathology.

    Science.gov (United States)

    Wilson, Heather; De Micco, Rosa; Niccolini, Flavia; Politis, Marios

    2017-01-01

    Huntington's disease (HD) is a progressive, monogenic dominant neurodegenerative disorder caused by repeat expansion mutation in the huntingtin gene. The accumulation of mutant huntingtin protein, forming intranuclear inclusions, subsequently leads to degeneration of medium spiny neurons in the striatum and cortical areas. Genetic testing can identify HD gene carriers before individuals develop overt cognitive, psychiatric, and chorea symptoms. Thus, HD gene carriers can be studied in premanifest stages to understand and track the evolution of HD pathology. While advances have been made, the precise pathophysiological mechanisms underlying HD are unclear. Magnetic resonance imaging (MRI) and positron emission tomography (PET) have been employed to understand HD pathology in presymptomatic and symptomatic disease stages. PET imaging uses radioactive tracers to detect specific changes, at a molecular level, which could be used as markers of HD progression and to monitor response to therapeutic treatments for HD gene expansion carriers (HDGECs). This review focuses on available PET techniques, employed in cross-sectional and longitudinal human studies, as biomarkers for HD, and highlights future potential PET targets. PET studies have assessed changes in postsynaptic dopaminergic receptors, brain metabolism, microglial activation, and recently phosphodiesterase 10A (PDE10A) as markers to track HD progression. Alterations in PDE10A expression are the earliest biochemical change identified in HD gene carriers up to 43 years before predicted symptomatic onset. Thus, PDE10A expression could be a promising marker to track HD progression from early premanifest disease stages. Other PET targets which have been less well investigated as biomarkers include cannabinoid, adenosine, and GABA receptors. Future longitudinal studies are required to fully validate these PET biomarkers for use to track disease progression from far-onset premanifest to manifest HD stages. PET imaging

  10. Adaptive tracking control for double-pendulum overhead cranes subject to tracking error limitation, parametric uncertainties and external disturbances

    Science.gov (United States)

    Zhang, Menghua; Ma, Xin; Rong, Xuewen; Tian, Xincheng; Li, Yibin

    2016-08-01

    In a practical application, overhead cranes are usually subjected to system parameter uncertainties, such as uncertain payload masses, cable lengths, frictions, and external disturbances, such as air resistance. Most existing crane control methods treat the payload swing as that of a single-pendulum. However, certain types of payloads and hoisting mechanisms result in double-pendulum dynamics. The double-pendulum effects will make most existing crane control methods fail to work normally. Therefore, an adaptive tracking controller for double-pendulum overhead cranes subject to parametric uncertainties and external disturbances is developed in this paper. The proposed adaptive tracking control method guarantees that the trolley tracking error is always within a prior set of boundary conditions and converges to zero rapidly. The asymptotic stability of the closed-loop system's equilibrium point is assured by Lyapunov techniques and Barbalat's Lemma. Simulation results show that the proposed adaptive tracking control method is robust with respect to system parametric uncertainties and external disturbances.

  11. Ghost marker detection and elimination in marker-based optical tracking systems for real-time tracking in stereotactic body radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Guanghua, E-mail: yan@ufl.edu; Li, Jonathan; Huang, Yin; Mittauer, Kathryn; Lu, Bo; Liu, Chihray [Department of Radiation Oncology, University of Florida, Gainesville, Florida 32610 (United States)

    2014-10-15

    Purpose: To propose a simple model to explain the origin of ghost markers in marker-based optical tracking systems (OTS) and to develop retrospective strategies to detect and eliminate ghost markers. Methods: In marker-based OTS, ghost markers are virtual markers created due to the cross-talk between the two camera sensors, which can lead to system execution failure or inaccuracy in patient tracking. As a result, the users have to limit the number of markers and avoid certain marker configurations to reduce the chances of ghost markers. In this work, the authors propose retrospective strategies to detect and eliminate ghost markers. The two camera sensors were treated as mathematical points in space. The authors identified the coplanar within limit (CWL) condition as the necessary condition for ghost marker occurrence. A simple ghost marker detection method was proposed based on the model. Ghost marker elimination was achieved through pattern matching: a ghost marker-free reference set was matched with the optical marker set observed by the OTS; unmatched optical markers were eliminated as either ghost markers or misplaced markers. The pattern matching problem was formulated as a constraint satisfaction problem (using pairwise distances as constraints) and solved with an iterative backtracking algorithm. Wildcard markers were introduced to address missing or misplaced markers. An experiment was designed to measure the sensor positions and the limit for the CWL condition. The ghost marker detection and elimination algorithms were verified with samples collected from a five-marker jig and a nine-marker anthropomorphic phantom, rotated with the treatment couch from −60° to +60°. The accuracy of the pattern matching algorithm was further validated with marker patterns from 40 patients who underwent stereotactic body radiotherapy (SBRT). For this purpose, a synthetic optical marker pattern was created for each patient by introducing ghost markers, marker position

  12. An External Focus of Attention Enhances Manual Tracking of Occluded and Visible Targets

    Directory of Open Access Journals (Sweden)

    Matthew eSchlesinger

    2013-01-01

    Full Text Available The present study investigated the enhancement effects of an external focus-of-attention (FOA in the context of a manual-tracking task, in which participants tracked both visible and occluded targets. Three conditions were compared, which manipulated the distance of the FOA from the participant as well as the external/internal dimension. As expected, an external FOA resulted in lower tracking errors than an internal FOA. In addition, analyses of participants' movement patterns revealed a systematic shift toward higher-frequency movements in the external FOA condition, consistent with the idea that an external FOA exploits the natural movement dynamics available during skilled action. Finally, target visibility did not influence the effect of focused attention on tracking performance, which provides evidence for the proposal that the mechanisms that underlie FOA do not depend directly on vision.

  13. Real-Time Tracking of Implanted Markers During Radiation Treatment by Use of Simultaneous kV and MV Imaging

    Science.gov (United States)

    2009-03-01

    imaging together with a MV electronic portal-imaging device (EPID). A Varian radiotherapy system equipped with both kV and MV imaging systems was used...direct (fiducial/image) in nature. In general, indirect tumor location methods, such as external skin marker tracking 10, 17, 18 or breath monitoring...more additional kV x-ray imaging systems, the technique may offer potential radiation sparing to the patient and overall system cost reductions. With

  14. Bacteriophages infecting Bacteroides as a marker for microbial source tracking.

    Science.gov (United States)

    Jofre, Joan; Blanch, Anicet R; Lucena, Francisco; Muniesa, Maite

    2014-05-15

    Bacteriophages infecting certain strains of Bacteroides are amid the numerous procedures proposed for tracking the source of faecal pollution. These bacteriophages fulfil reasonably well most of the requirements identified as appropriate for a suitable marker of faecal sources. Thus, different host strains are available that detect bacteriophages preferably in water contaminated with faecal wastes corresponding to different animal species. For phages found preferably in human faecal wastes, which are the ones that have been more extensively studied, the amounts of phages found in waters contaminated with human fecal samples is reasonably high; these amounts are invariable through the time; their resistance to natural and anthropogenic stressors is comparable to that of other relatively resistant indicator of faecal pollution such us coliphages; the abundance ratios of somatic coliphages and bacteriophages infecting Bacteroides thetaiotaomicron GA17 are unvarying in recent and aged contamination; and standardised detection methods exist. These methods are easy, cost effective and provide data susceptible of numerical analysis. In contrast, there are some uncertainties regarding their geographical stability, and consequently suitable hosts need to be isolated for different geographical areas. However, a feasible method has been described to isolate suitable hosts in a given geographical area. In summary, phages infecting Bacteroides are a marker of faecal sources that in our opinion merits being included in the "toolbox" for microbial source tracking. However, further research is still needed in order to make clear some uncertainties regarding some of their characteristics and behaviour, to compare their suitability to the one of emerging methods such us targeting Bacteroidetes by qPCR assays; or settling molecular methods for their determination.

  15. Optical Tracking With Two Markers for Robust Prospective Motion Correction for Brain Imaging

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    Singh, Aditya; Zahneisen, Benjamin; Keating, Brian; Herbst, Michael; Chang, Linda; Zaitsev, Maxim; Ernst, Thomas

    2017-01-01

    Object Prospective motion correction (PMC) during brain imaging using camera-based tracking of a skin-attached marker may suffer from problems including loss of marker visibility due to the coil and false correction due to non-rigid-body facial motion, such as frowning or squinting. A modified PMC system is introduced to mitigate these problems and increase the robustness of motion correction. Materials and Methods The method relies on simultaneously tracking two markers, each providing six degrees of freedom, that are placed on the forehead. This allows us to track head motion when one marker is obscured, and detect skin movements to prevent false corrections. Experiments were performed to compare the performance of the two-marker motion correction technique to the previous single-marker approach. Results Experiments validate the theory developed for adaptive marker tracking and skin movement detection, and demonstrate improved image quality during obstruction of the line-of-sight of one marker, when subjects squint, or when subjects squint and move simultaneously. Conclusion The proposed methods eliminate two common failure modes of PMC and substantially improve the robustness of PMC and can be applied to other optical tracking systems capable of tracking multiple markers. The methods presented can be adapted to the use of more than two markers. PMID:26121941

  16. Comparison of external motion tracking systems for PET list-mode reconstruction

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Keller, Sune H.

    2011-01-01

    attachment of markers to the subject introducing image artifacts on human scans. We have previously designed a camera-based structured light (SL) system for 3D head tracking used with the high resolution research tomograph (HRRT, Siemens, Knoxville, USA) [5]. The system was modified to use invisible light...... markerless tracking system is not trivial to provide and to our knowledge not presently existent. The Polaris Vicra optical tracking system (Northern Digital Inc.) is generally used with PET brain imaging and has been demonstrated to work very well on phantoms [4]. However, it suffers from the necessary...

  17. Decay of Fecal Indicator Bacteria and Microbial Source Tracking Markers in Cattle Feces

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    The survival of fecal indicator bacteria (FIB) and microbial source tracking (MST) markers in water microcosms and manure amended soils has been well documented; however, little is known about the survival of MST markers in bovine feces deposited on pastures. We conducted a study...

  18. Adaptive external torque estimation by means of tracking a Lyapunov function

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, H.; Junkins, J.L. [Texas A and M Univ., College Station, TX (United States); Robinett, R.D. [Sandia National Labs., Albuquerque, NM (United States)

    1996-03-01

    A real-time method is presented to adoptively estimate three-dimensional unmodeled external torques acting on a spacecraft. This is accomplished by forcing the tracking error dynamics to follow the Lyapunov function underlying the feedback control law. For the case where the external torque is constant, the tracking error dynamics are shown to converge asypmtotically. The methodology applies not only to the control law used in this paper, but can also be applied to most Lyapunov derived feedback control laws. The adaptive external torque estimation is very robust in the presence of measurement noise, since a numerical integration is used instead of a numerical differentiation. Spacecraft modeling errors, such as in the inertia matrix, are also compensated for by this method. Several examples illustrate the practical significance of these ideas.

  19. A 4D ultrasound real-time tracking system for external beam radiotherapy of upper abdominal lesions under breath-hold

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    Sihono, Dwi Seno Kuncoro; Vogel, Lena; Thoelking, Johannes; Wenz, Frederik; Boda-Heggemann, Judit; Wertz, Hansjoerg [University of Heidelberg, Department of Radiation Oncology, University Medical Center Mannheim, Mannheim (Germany); Weiss, Christel [University of Heidelberg, Department of Biomathematics and Medical Statistics, University Medical Center Mannheim, Mannheim (Germany); Lohr, Frank [University of Heidelberg, Department of Radiation Oncology, University Medical Center Mannheim, Mannheim (Germany); Az. Ospedaliero-Universitaria di Modena, Struttura Complessa di Radioterapia, Dipartimento di Oncologia, Modena (Italy)

    2017-03-15

    To evaluate a novel four-dimensional (4D) ultrasound (US) tracking system for external beam radiotherapy of upper abdominal lesions under computer-controlled deep-inspiration breath-hold (DIBH). The tracking accuracy of the research 4D US system was evaluated using two motion phantoms programmed with sinusoidal and breathing patterns to simulate free breathing and DIBH. Clinical performance was evaluated with five healthy volunteers. US datasets were acquired in computer-controlled DIBH with varying angular scanning angles. Tracked structures were renal pelvis (spherical structure) and portal/liver vein branches (non-spherical structure). An external marker was attached to the surface of both phantoms and volunteers as a secondary object to be tracked by an infrared camera for comparison. Phantom measurements showed increased accuracy of US tracking with decreasing scanning range/increasing scanning frequency. The probability of lost tracking was higher for small scanning ranges (43.09% for 10 and 13.54% for 20 ).The tracking success rates in healthy volunteers during DIBH were 93.24 and 89.86% for renal pelvis and portal vein branches, respectively. There was a strong correlation between marker motion and US tracking for the majority of analyzed breath-holds: 84.06 and 88.41% of renal pelvis target results and 82.26 and 91.94% of liver vein target results in anteroposterior and superoinferior directions, respectively; Pearson's correlation coefficient was between 0.71 and 0.99. The US system showed a good tracking performance in 4D motion phantoms. The tracking capability of surrogate structures for upper abdominal lesions in DIBH fulfills clinical requirements. Further investigation in a larger cohort of patients is underway. (orig.) [German] Evaluation eines neuen vierdimensionalen (4D) Ultraschall(US)-Tracking-Systems fuer die externe Strahlentherapie von Oberbauchlaesionen unter computergesteuertem tiefem Atemanhalt (DIBH). Die Tracking-Genauigkeit des 4D

  20. Resource Saving Approach of Visual Tracking Fiducial Marker Recognition for Unmanned Aerial Vehicle

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    Arunas Andziulis

    2015-01-01

    Full Text Available Unmanned aerial vehicle (UAV tracking fiducial marker is a challenging problem, because of camera system vibration, which causes visible frame-to-frame jitter in the airborne videos and unclear marker vision. Multirotors have very limited weight carrying, controller, and battery power resources. While obtaining and processing motion blurred images, which have no useful information, requires much more image processing subsystem resources. The paper presents blurry image frame elimination based approach of UAV resource saving fiducial marker visual tracking. The proposed approach integrates accelerometer and visual data processing algorithms to predict image blur and skip blurred frames. Experiments have been performed to verify the validity of the proposed approach.

  1. PADC Detected External Neutron Field by Nuclear Tracks at RFX-mod

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    W. Gonzalez

    2014-08-01

    Full Text Available Measured neutron signals relevant for plasma diagnostics on Reversed Field pinch eXperiment, RFX-mod, are obtained by nuclear track methodology with PADC-NTD’s. This technique provides the external neutron field values around the RFX-mod installation during pulsed operation. Charged particles from (n, p and (n, α reactions are related to formed latent tracks. These are etched in a thermoregulated water bath with a 6.25M, KOH solution at 60o C. Observed tracks were analyzed to determine track density from which neutron fluence spatial values should be derived. Results indicate that the neutron density in the surrounding environment change at most 40%. The epithermal component is 60% higher than that corresponding to the thermal region. The estimated neutron fluence for the whole experiment is 7.5×1010 neutrons cm2 /s.

  2. Observer-based approximate optimal tracking control for time-delay systems with external disturbances

    Science.gov (United States)

    Su, Hao; Tang, Gong-You

    2016-09-01

    This paper proposes a successive approximation design approach of observer-based optimal tracking controllers for time-delay systems with external disturbances. To solve a two-point boundary value problem with time-delay and time-advance terms and obtain the optimal tracking control law, two sequences of vector differential equations are constructed first. Second, the convergence of the sequences of the vector differential equations is proved to guarantee the existence and uniqueness of the control law. Third, a design algorithm of the optimal tracking control law is presented and the physically realisable problem is addressed by designing a disturbance state observer and a reference input state observer. An example of an industrial electric heater is given to demonstrate the efficiency of the proposed approach.

  3. Automatic tracking of arbitrarily shaped implanted markers in kilovoltage projection images: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Regmi, Rajesh; Lovelock, D. Michael; Hunt, Margie; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D.; Mageras, Gig S., E-mail: magerasg@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 (United States); Goodman, Karyn A.; Rimner, Andreas [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 (United States); Mostafavi, Hassan [Ginzton Technology Center, Varian Medical Systems, Palo Alto, California 94304 (United States)

    2014-07-15

    Purpose: Certain types of commonly used fiducial markers take on irregular shapes upon implantation in soft tissue. This poses a challenge for methods that assume a predefined shape of markers when automatically tracking such markers in kilovoltage (kV) radiographs. The authors have developed a method of automatically tracking regularly and irregularly shaped markers using kV projection images and assessed its potential for detecting intrafractional target motion during rotational treatment. Methods: Template-based matching used a normalized cross-correlation with simplex minimization. Templates were created from computed tomography (CT) images for phantom studies and from end-expiration breath-hold planning CT for patient studies. The kV images were processed using a Sobel filter to enhance marker visibility. To correct for changes in intermarker relative positions between simulation and treatment that can introduce errors in automatic matching, marker offsets in three dimensions were manually determined from an approximately orthogonal pair of kV images. Two studies in anthropomorphic phantom were carried out, one using a gold cylindrical marker representing regular shape, another using a Visicoil marker representing irregular shape. Automatic matching of templates to cone beam CT (CBCT) projection images was performed to known marker positions in phantom. In patient data, automatic matching was compared to manual matching as an approximate ground truth. Positional discrepancy between automatic and manual matching of less than 2 mm was assumed as the criterion for successful tracking. Tracking success rates were examined in kV projection images from 22 CBCT scans of four pancreas, six gastroesophageal junction, and one lung cancer patients. Each patient had at least one irregularly shaped radiopaque marker implanted in or near the tumor. In addition, automatic tracking was tested in intrafraction kV images of three lung cancer patients with irregularly shaped

  4. Oxidative Stress Markers in Prostate Cancer Patients after HDR Brachytherapy Combined with External Beam Radiation

    OpenAIRE

    Alina Woźniak; Rafał Masiak; Michał Szpinda; Celestyna Mila-Kierzenkowska; Bartosz Woźniak; Roman Makarewicz; Anna Szpinda

    2012-01-01

    Assessment of oxidative stress markers was perfomed in prostate cancer (PCa) patients subjected to high-dose brachytherapy (HDR) with external beam radiotherapy (EBRT). Sixty men with PCa were subjected to combined two-fraction treatment with HDR (tot. 20 Gy) and EBRT (46 Gy). Blood samples were taken before treatment, immediately afterwards, after 1.5–3 months, and approx. 2 years. Control group consisted of 30 healthy men. Erythrocyte glutathione peroxidase activity in the patients was lowe...

  5. Alternative fiducial markers for Vero real-time tumor tracking radiotherapy: A phantom study

    Science.gov (United States)

    Park, Shin-Hyung; Kim, Jae-Chul; Kim, Sung Joon

    2016-12-01

    The objective of this study was to investigate the feasibility of potential fiducial markers consisting of various materials in a Vero real-time tumor-tracking (RTTT) system. In order to determine the applicability of fiducial markers for the Vero RTTT system, we tested various markers consisting of 8 kinds of material (titanium, stainless steel, high-carbon steel, pure steel, copper, silver, tantalum, and gold) with various diameters ranging from 0.3 mm to 1.6 mm and a length of 5 mm. Additionally, a commercial gold coil marker (Visicoil™, IBA dosimetry, Schwarzenbruck, Germany) of diameter 0.5 mm and length 1 cm was included for evaluation. The radiologic visibility on kV fluoroscopy/kV CT scan images of the fiducial markers was evaluated. The detectability on the RTTT system was tested using a two-dimensional moving phantom (Brainlab AG, Feldkirchen, Germany), producing sinusoidal motion. The target center's accuracy was evaluated by calculating the deviation of the position of a metal sphere from the center on the dose profile. Dose profiles were measured using Gafchromic EBT2 films (International Specialty Products, NJ, USA). All markers were visible on kV fluoroscopy/kV CT while markers with atomic number ≥ 25.7 were detectable on the Vero RTTT system. All the detected markers showed excellent geometric accuracy.

  6. Tracking Dissipation Reduction, Externalities, Stability and Sustainability for Environmental Management of New Orleans

    Science.gov (United States)

    McNamara, D.; Werner, B. T.

    2014-12-01

    Sustainability requires stability, but in promoting economic development, modern economies and political systems reduce stabilizing dissipation by facilitating use and management of the environment through engineered mitigation of disturbances, which externalizes dissipation over the short to medium term. To quantitatively investigate the relationship between a range of environmental management approaches and sustainability, and the implications for Earth's future, we track the impact of management strategies on dissipation within the system and its externalities in a numerical model for the coupled economic, political/management and flooding dynamics of New Orleans. The model simulates river floods, hurricane storm-surge-induced floods, subsidence, and agent-based market interactions leading to development of port services, hotels, homes and labor relations. Flood protection decisions for levee construction based on the baseline case of cost-benefit analyses designed to prevent short-term economic loss from future floods qualitatively reproduce historical expansion of New Orleans and increases in levee height. Alternative management strategies explored include majority voting, consensus-based decision-making, and variations in discounting of costs and benefits. Enhanced dissipation is measured relative to optimal economic development without floods. The focus of modern economies on commodification is exploited to track dissipation as a scalar representing value or power, but this approach might not be applicable to more complicated traditional/indigenous cultures or cultures of resistance. For the baseline case, short-to-medium-term reductions in dissipation destabilize the coupled system, resulting in episodic bursts of externalized dissipation during flooding. Comparisons of results for a range of management options and generalizations of this approach for alternative cultural systems will be discussed.

  7. Fast internal marker tracking algorithm for onboard MV and kV imaging systems.

    Science.gov (United States)

    Mao, W; Wiersma, R D; Xing, L

    2008-05-01

    Intrafraction organ motion can limit the advantage of highly conformal dose techniques such as intensity modulated radiation therapy (IMRT) due to target position uncertainty. To ensure high accuracy in beam targeting, real-time knowledge of the target location is highly desired throughout the beam delivery process. This knowledge can be gained through imaging of internally implanted radio-opaque markers with fluoroscopic or electronic portal imaging devices (EPID). In the case of MV based images, marker detection can be problematic due to the significantly lower contrast between different materials in comparison to their kV-based counterparts. This work presents a fully automated algorithm capable of detecting implanted metallic markers in both kV and MV images with high consistency. Using prior CT information, the algorithm predefines the volumetric search space without manual region-of-interest (ROI) selection by the user. Depending on the template selected, both spherical and cylindrical markers can be detected. Multiple markers can be simultaneously tracked without indexing confusion. Phantom studies show detection success rates of 100% for both kV and MV image data. In addition, application of the algorithm to real patient image data results in successful detection of all implanted markers for MV images. Near real-time operational speeds of approximately 10 frames/sec for the detection of five markers in a 1024 x 768 image are accomplished using an ordinary PC workstation.

  8. A Reductionist Approach to Extract Robust Molecular Markers from Microarray Data Series -Isolating Markers to Track Osseointegration.

    Science.gov (United States)

    Barik, Anwesha; Banerjee, Satarupa; Dhara, Santanu; Chakravorty, Nishant

    2017-03-10

    Complexities in the full genome expression studies hinder the extraction of tracker genes to analyze the course of biological events. In this study, we demonstrate the applications of supervised machine learning methods to reduce the irrelevance in microarray data series and thereby extract robust molecular markers to track biological processes. The methodology has been illustrated by analyzing whole genome expression studies on bone-implant integration (ossointegration). Being a biological process, osseointegration is known to leave a trail of genetic footprint during the course. In spite of existence of enormous amount of raw data in public repositories, researchers still do not have access to a panel of genes that can definitively track osseointegrtion. The results from our study revealed panels comprising of matrix metalloproteinases and collagen genes were able to track osseointegration on implant surfaces (MMP9 and COL1A2 on micro-textured; MMP12 and COL6A3 on superimposed nano-textured surfaces) 100% classification accuracy, specificity and sensitivity. Further, our analysis showed the importance of the progression of the duration in establishment of the mechanical connection at bone-implant surface. The findings from this study are expected to be useful to researchers investigating osseointegration of novel implant materials especially at the early stage. The methodology demonstrated can be easily adapted by scientists in different fields to analyze large databases for other biological processes.

  9. Oxidative Stress Markers in Prostate Cancer Patients after HDR Brachytherapy Combined with External Beam Radiation

    Directory of Open Access Journals (Sweden)

    Alina Woźniak

    2012-01-01

    Full Text Available Assessment of oxidative stress markers was perfomed in prostate cancer (PCa patients subjected to high-dose brachytherapy (HDR with external beam radiotherapy (EBRT. Sixty men with PCa were subjected to combined two-fraction treatment with HDR (tot. 20 Gy and EBRT (46 Gy. Blood samples were taken before treatment, immediately afterwards, after 1.5–3 months, and approx. 2 years. Control group consisted of 30 healthy men. Erythrocyte glutathione peroxidase activity in the patients was lower than in healthy subjects by 34% (, 50% (, 30% (, and 61% (, respectively, at all periods. No significant differences were found by comparing superoxide dismutase and catalase activity in PCa patients with that of the controls. After 2 years of the end of treatment, the activity of studied enzymes demonstrated a decreasing tendency versus before therapy. Blood plasma thiobarbituric acid reactive substances (TBARS concentration was higher than in the controls at all periods, while erythrocyte TBARS decreased after 2 years to control levels. The results confirm that in the course of PCa, imbalance of oxidant-antioxidant processes occurs. The therapy did not alter the levels of oxidative stress markers, which may prove its applicability. Two years is too short a period to restore the oxidant-antioxidant balance.

  10. Application of leftover sample material from waterborne protozoa monitoring for the molecular detection of Bacteroidales and fecal source tracking markers

    Science.gov (United States)

    In this study, we examined the potential for detecting fecal bacteria and microbial source tracking markers in samples discarded during the concentration of Cryptosporidium and Giardia using USEPA Method 1623. Recovery rates for different fecal bacteria were determined using sp...

  11. Application of leftover sample material from waterborne protozoa monitoring for the molecular detection of Bacteroidales and fecal source tracking markers

    Science.gov (United States)

    In this study, we examined the potential for detecting fecal bacteria and microbial source tracking markers in samples discarded during the concentration of Cryptosporidium and Giardia using USEPA Method 1623. Recovery rates for different fecal bacteria were determined using sp...

  12. Optical eye tracking system for real-time noninvasive tumor localization in external beam radiotherapy.

    Science.gov (United States)

    Via, Riccardo; Fassi, Aurora; Fattori, Giovanni; Fontana, Giulia; Pella, Andrea; Tagaste, Barbara; Riboldi, Marco; Ciocca, Mario; Orecchia, Roberto; Baroni, Guido

    2015-05-01

    External beam radiotherapy currently represents an important therapeutic strategy for the treatment of intraocular tumors. Accurate target localization and efficient compensation of involuntary eye movements are crucial to avoid deviations in dose distribution with respect to the treatment plan. This paper describes an eye tracking system (ETS) based on noninvasive infrared video imaging. The system was designed for capturing the tridimensional (3D) ocular motion and provides an on-line estimation of intraocular lesions position based on a priori knowledge coming from volumetric imaging. Eye tracking is performed by localizing cornea and pupil centers on stereo images captured by two calibrated video cameras, exploiting eye reflections produced by infrared illumination. Additionally, torsional eye movements are detected by template matching in the iris region of eye images. This information allows estimating the 3D position and orientation of the eye by means of an eye local reference system. By combining ETS measurements with volumetric imaging for treatment planning [computed tomography (CT) and magnetic resonance (MR)], one is able to map the position of the lesion to be treated in local eye coordinates, thus enabling real-time tumor referencing during treatment setup and irradiation. Experimental tests on an eye phantom and seven healthy subjects were performed to assess ETS tracking accuracy. Measurements on phantom showed an overall median accuracy within 0.16 mm and 0.40° for translations and rotations, respectively. Torsional movements were affected by 0.28° median uncertainty. On healthy subjects, the gaze direction error ranged between 0.19° and 0.82° at a median working distance of 29 cm. The median processing time of the eye tracking algorithm was 18.60 ms, thus allowing eye monitoring up to 50 Hz. A noninvasive ETS prototype was designed to perform real-time target localization and eye movement monitoring during ocular radiotherapy treatments. The

  13. Optical eye tracking system for real-time noninvasive tumor localization in external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Via, Riccardo, E-mail: riccardo.via@polimi.it; Fassi, Aurora; Fattori, Giovanni [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano 20133 (Italy); Fontana, Giulia; Pella, Andrea; Tagaste, Barbara; Ciocca, Mario [CNAO Centro Nazionale di Adroterapia Oncologica, Pavia 27100 (Italy); Riboldi, Marco; Baroni, Guido [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano 20133, Italy and CNAO Centro Nazionale di Adroterapia Oncologica, Pavia 27100 (Italy); Orecchia, Roberto [CNAO Centro Nazionale di Adroterapia Oncologica, Pavia 27100, Italy and European Institute of Oncology, Milano 20141 (Italy)

    2015-05-15

    Purpose: External beam radiotherapy currently represents an important therapeutic strategy for the treatment of intraocular tumors. Accurate target localization and efficient compensation of involuntary eye movements are crucial to avoid deviations in dose distribution with respect to the treatment plan. This paper describes an eye tracking system (ETS) based on noninvasive infrared video imaging. The system was designed for capturing the tridimensional (3D) ocular motion and provides an on-line estimation of intraocular lesions position based on a priori knowledge coming from volumetric imaging. Methods: Eye tracking is performed by localizing cornea and pupil centers on stereo images captured by two calibrated video cameras, exploiting eye reflections produced by infrared illumination. Additionally, torsional eye movements are detected by template matching in the iris region of eye images. This information allows estimating the 3D position and orientation of the eye by means of an eye local reference system. By combining ETS measurements with volumetric imaging for treatment planning [computed tomography (CT) and magnetic resonance (MR)], one is able to map the position of the lesion to be treated in local eye coordinates, thus enabling real-time tumor referencing during treatment setup and irradiation. Experimental tests on an eye phantom and seven healthy subjects were performed to assess ETS tracking accuracy. Results: Measurements on phantom showed an overall median accuracy within 0.16 mm and 0.40° for translations and rotations, respectively. Torsional movements were affected by 0.28° median uncertainty. On healthy subjects, the gaze direction error ranged between 0.19° and 0.82° at a median working distance of 29 cm. The median processing time of the eye tracking algorithm was 18.60 ms, thus allowing eye monitoring up to 50 Hz. Conclusions: A noninvasive ETS prototype was designed to perform real-time target localization and eye movement monitoring

  14. Adaptive tracking control of leader-following linear multi-agent systems with external disturbances

    Science.gov (United States)

    Lin, Hanquan; Wei, Qinglai; Liu, Derong; Ma, Hongwen

    2016-10-01

    In this paper, the consensus problem for leader-following linear multi-agent systems with external disturbances is investigated. Brownian motions are used to describe exogenous disturbances. A distributed tracking controller based on Riccati inequalities with an adaptive law for adjusting coupling weights between neighbouring agents is designed for leader-following multi-agent systems under fixed and switching topologies. In traditional distributed static controllers, the coupling weights depend on the communication graph. However, coupling weights associated with the feedback gain matrix in our method are updated by state errors between neighbouring agents. We further present the stability analysis of leader-following multi-agent systems with stochastic disturbances under switching topology. Most traditional literature requires the graph to be connected all the time, while the communication graph is only assumed to be jointly connected in this paper. The design technique is based on Riccati inequalities and algebraic graph theory. Finally, simulations are given to show the validity of our method.

  15. Repurposing the Microsoft Kinect for Windows v2 for external head motion tracking for brain PET

    Science.gov (United States)

    Noonan, P. J.; Howard, J.; Hallett, W. A.; Gunn, R. N.

    2015-11-01

    Medical imaging systems such as those used in positron emission tomography (PET) are capable of spatial resolutions that enable the imaging of small, functionally important brain structures. However, the quality of data from PET brain studies is often limited by subject motion during acquisition. This is particularly challenging for patients with neurological disorders or with dynamic research studies that can last 90 min or more. Restraining head movement during the scan does not eliminate motion entirely and can be unpleasant for the subject. Head motion can be detected and measured using a variety of techniques that either use the PET data itself or an external tracking system. Advances in computer vision arising from the video gaming industry could offer significant benefits when re-purposed for medical applications. A method for measuring rigid body type head motion using the Microsoft Kinect v2 is described with results presenting  ⩽0.5 mm spatial accuracy. Motion data is measured in real-time at 30 Hz using the KinectFusion algorithm. Non-rigid motion is detected using the residual alignment energy data of the KinectFusion algorithm allowing for unreliable motion to be discarded. Motion data is aligned to PET listmode data using injected pulse sequences into the PET/CT gantry allowing for correction of rigid body motion. Pilot data from a clinical dynamic PET/CT examination is shown.

  16. Registration and display of brain SPECT and MRI using external markers.

    Science.gov (United States)

    Pohjonen, H; Nikkinen, P; Sipilä, O; Launes, J; Salli, E; Salonen, O; Karp, P; Ylä-Jääski, J; Katila, T; Liewendahl, K

    1996-02-01

    Accurate anatomical localisation of abnormalities observed in brain perfusion single-photon emission computed tomography (SPECT) is difficult, but can be improved by correlating data from SPECT and other tomographic imaging modalities. For this purpose we have developed software to register, analyse and display 99mTc-hexamethylpropyleneamine oxime SPECT and 1.0 T MRI of the brain. For registration of SPECT and MRI data external skin markers containing 99mTc (220 kBq) in 50 microliters of coconut butter were used. The software is coded in the C programming language, and the X Window system and the OSF/Motif standards are used for graphics and definition of the user interface. The registration algorithm follows a noniterative least-squares method using singular value decomposition of a 3 x 3 covariance matrix. After registration, the image slices of both data sets are shown at identical tomographic levels. The registration error in phantom studies was on average 4 mm. In the two-dimensional display mode the orthogonal cross-sections of the data sets are displayed side by side. In the three-dimensional mode MRI data are displayed as a surface-shaded 3 D reconstruction and SPECT data as cut planes. The usefulness of this method is demonstrated in patients with cerebral infarcts, brain tumour, herpes simplex encephalitis and epilepsy.

  17. Registration and display of brain SPECT and MRI using external markers

    Energy Technology Data Exchange (ETDEWEB)

    Pohjonen, H. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland); Nikkinen, P. [Department of Clinical Chemistry, Division of Nuclear Medicine, Helsinki University Central Hospital, Helsinki (Finland); Sipilae, O. [Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Launes, J. [Department of Neurology, Helsinki University Central Hospital, Helsinki (Finland); Salli, E. [Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Salonen, O. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Karp, P. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland); Ylae-Jaeaeski, J. [Graphic Arts Laboratory, Technical Research Centre of Finland, Espoo (Finland); Katila, T. [Medical Engineering Centre, Helsinki University Central Hospital, Stenbaeckinkatu 9, FIN-00290 Helsinki (Finland)]|[Laboratory of Biomedical Engineering, Helsinki University of Technology, Espoo (Finland); Liewendahl, K. [Department of Clinical Chemistry, Division of Nuclear Medicine, Helsinki University Central Hospital, Helsinki (Finland)

    1996-02-01

    Accurate anatomical localisation of abnormalities observed in brain perfusion single-photon emission computed tomography (SPECT) is difficult, but can be improved by correlating data from SPECT and other tomographic imaging modalities. For this purpose we have developed software to register, analyse and display {sup 99m}Tc-hexamethylpropyleneamine oxime SPECT and 1.0 T MRI of the brain. For registration of SPECT and MRI data external skin markers containing {sup 99m}Tc (220 kBq) in 50 {mu}l of coconut butter were used. The software is coded in the C programming language, and the X Window system and the OSF/Motif standards are used for graphics and definition of the user interface. The registration algorithm follows a noniterative least-squares method using singular value decomposition of a 3 x 3 covariance matrix. After registration, the image slices of both data sets are shown at identical tomographic levels. The registration error in phantom studies was on average 4 mm. In the two-dimensional display mode the orthogonal cross-sections of the data sets are displayed side by side. In the three-dimensional mode MRI data are displayed as a surface-shaded 3 D reconstruction and SPECT data as cut planes. The usefulness of this method is demonstrated in patients with cerebral infarcts, brain tumour, herpes simplex encephalitis and epilepsy. (orig.). With 9 figs.

  18. Intra-operative prostate motion tracking using surface markers for robot-assisted laparoscopic radical prostatectomy

    Science.gov (United States)

    Esteghamatian, Mehdi; Sarkar, Kripasindhu; Pautler, Stephen E.; Chen, Elvis C. S.; Peters, Terry M.

    2012-02-01

    Radical prostatectomy surgery (RP) is the gold standard for treatment of localized prostate cancer (PCa). Recently, emergence of minimally invasive techniques such as Laparoscopic Radical Prostatectomy (LRP) and Robot-Assisted Laparoscopic Radical Prostatectomy (RARP) has improved the outcomes for prostatectomy. However, it remains difficult for the surgeons to make informed decisions regarding resection margins and nerve sparing since the location of the tumor within the organ is not usually visible in a laparoscopic view. While MRI enables visualization of the salient structures and cancer foci, its efficacy in LRP is reduced unless it is fused into a stereoscopic view such that homologous structures overlap. Registration of the MRI image and peri-operative ultrasound image using a tracked probe can potentially be exploited to bring the pre-operative information into alignment with the patient coordinate system during the procedure. While doing so, prostate motion needs to be compensated in real-time to synchronize the stereoscopic view with the pre-operative MRI during the prostatectomy procedure. In this study, a point-based stereoscopic tracking technique is investigated to compensate for rigid prostate motion so that the same motion can be applied to the pre-operative images. This method benefits from stereoscopic tracking of the surface markers implanted over the surface of the prostate phantom. The average target registration error using this approach was 3.25+/-1.43mm.

  19. Distributed Time-Varying Formation Robust Tracking for General Linear Multiagent Systems With Parameter Uncertainties and External Disturbances.

    Science.gov (United States)

    Hua, Yongzhao; Dong, Xiwang; Li, Qingdong; Ren, Zhang

    2017-05-18

    This paper investigates the time-varying formation robust tracking problems for high-order linear multiagent systems with a leader of unknown control input in the presence of heterogeneous parameter uncertainties and external disturbances. The followers need to accomplish an expected time-varying formation in the state space and track the state trajectory produced by the leader simultaneously. First, a time-varying formation robust tracking protocol with a totally distributed form is proposed utilizing the neighborhood state information. With the adaptive updating mechanism, neither any global knowledge about the communication topology nor the upper bounds of the parameter uncertainties, external disturbances and leader's unknown input are required in the proposed protocol. Then, in order to determine the control parameters, an algorithm with four steps is presented, where feasible conditions for the followers to accomplish the expected time-varying formation tracking are provided. Furthermore, based on the Lyapunov-like analysis theory, it is proved that the formation tracking error can converge to zero asymptotically. Finally, the effectiveness of the theoretical results is verified by simulation examples.

  20. Relationship of human-associated microbial source tracking markers with Enterococci in Gulf of Mexico waters.

    Science.gov (United States)

    Gordon, Katrina V; Brownell, Miriam; Wang, Shiao Y; Lepo, Joe Eugene; Mott, Joanna; Nathaniel, Rajkumar; Kilgen, Marilyn; Hellein, Kristen N; Kennedy, Elizabeth; Harwood, Valerie J

    2013-03-01

    Human and ecosystem health can be damaged by fecal contamination of recreational waters. Microbial source tracking (MST) can be used to specifically detect domestic sewage containing human waste, thereby informing both risk assessment and remediation strategies. Previously, an inter-laboratory collaboration developed standardized PCR methods for a bacterial, an archaeal, and a viral indicator of human sewage. Here we present results for two subsequent years of field testing in fresh and salt water by five laboratories across the U.S. Gulf Coast (two in Florida and one each in Mississippi, Louisiana and Texas) using common standard operating procedures (SOPs) developed previously. Culturable enterococci were enumerated by membrane filtration, and PCR was used to detect three MST markers targeting domestic sewage: human-associated Bacteroides (HF183), Methanobrevibacter smithii and human polyomaviruses BK and JC (HPyVs). Detection of sewage markers in surface waters was significantly associated with higher enterococci levels and with exceedance of the recreational water quality standard in four or three regions, respectively. Sewage markers were frequently co-detected in single samples, e.g., M. smithii and HF183 were co-detected in 81% of Louisiana samples, and HPyVs and M. smithii were co-detected in over 40% of southwest Florida and Mississippi samples. This study demonstrates the robustness and inter-laboratory transferability of these three markers for the detection of pollution from domestic sewage in the waters impacting the Gulf of Mexico over a coastal range of over 1000 miles. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Coding SNPs as intrinsic markers for sample tracking in large-scale transcriptome studies.

    Science.gov (United States)

    Xu, Weihong; Gao, Hong; Seok, Junhee; Wilhelmy, Julie; Mindrinos, Michael N; Davis, Ronald W; Xiao, Wenzhong

    2012-06-01

    Large-scale transcriptome profiling in clinical studies often involves assaying multiple samples of a patient to monitor disease progression, treatment effect, and host response in multiple tissues. Such profiling is prone to human error, which often results in mislabeled samples. Here, we present a method to detect mislabeled sample outliers using coding single nucleotide polymorphisms (cSNPs) specifically designed on the microarray and demonstrate that the mislabeled samples can be efficiently identified by either simple clustering of allele-specific expression scores or Mahalanobis distance-based outlier detection method. Based on our results, we recommend the incorporation of cSNPs into future transcriptome array designs as intrinsic markers for sample tracking.

  2. Remote Marker-Based Tracking for UAV Landing Using Visible-Light Camera Sensor.

    Science.gov (United States)

    Nguyen, Phong Ha; Kim, Ki Wan; Lee, Young Won; Park, Kang Ryoung

    2017-08-30

    Unmanned aerial vehicles (UAVs), which are commonly known as drones, have proved to be useful not only on the battlefields where manned flight is considered too risky or difficult, but also in everyday life purposes such as surveillance, monitoring, rescue, unmanned cargo, aerial video, and photography. More advanced drones make use of global positioning system (GPS) receivers during the navigation and control loop which allows for smart GPS features of drone navigation. However, there are problems if the drones operate in heterogeneous areas with no GPS signal, so it is important to perform research into the development of UAVs with autonomous navigation and landing guidance using computer vision. In this research, we determined how to safely land a drone in the absence of GPS signals using our remote maker-based tracking algorithm based on the visible light camera sensor. The proposed method uses a unique marker designed as a tracking target during landing procedures. Experimental results show that our method significantly outperforms state-of-the-art object trackers in terms of both accuracy and processing time, and we perform test on an embedded system in various environments.

  3. Automated marker tracking using noisy X-ray images degraded by the treatment beam

    Energy Technology Data Exchange (ETDEWEB)

    Wisotzky, E. [Fraunhofer Institute for Production Systems and Design Technology (IPK), Berlin (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Fast, M.F.; Nill, S. [The Royal Marsden NHS Foundation Trust, London (United Kingdom). Joint Dept. of Physics; Oelfke, U. [The Royal Marsden NHS Foundation Trust, London (United Kingdom). Joint Dept. of Physics; German Cancer Research Center (DKFZ), Heidelberg (Germany)

    2015-09-01

    This study demonstrates the feasibility of automated marker tracking for the real-time detection of intrafractional target motion using noisy kilovoltage (kV) X-ray images degraded by the megavoltage (MV) treatment beam. The authors previously introduced the in-line imaging geometry, in which the flat-panel detector (FPD) is mounted directly underneath the treatment head of the linear accelerator. They found that the 121 kVp image quality was severely compromised by the 6 MV beam passing through the FPD at the same time. Specific MV-induced artefacts present a considerable challenge for automated marker detection algorithms. For this study, the authors developed a new imaging geometry by re-positioning the FPD and the X-ray tube. This improved the contrast-to-noise-ratio between 40% and 72% at the 1.2 mAs/image exposure setting. The increase in image quality clearly facilitates the quick and stable detection of motion with the aid of a template matching algorithm. The setup was tested with an anthropomorphic lung phantom (including an artificial lung tumour). In the tumour one or three Calypso {sup registered} beacons were embedded to achieve better contrast during MV radiation. For a single beacon, image acquisition and automated marker detection typically took around 76±6 ms. The success rate was found to be highly dependent on imaging dose and gantry angle. To eliminate possible false detections, the authors implemented a training phase prior to treatment beam irradiation and also introduced speed limits for motion between subsequent images.

  4. US/MRI fusion with new optical tracking and marker approach for interventional procedures inside the MRI suite

    Directory of Open Access Journals (Sweden)

    Nagaraj Yeshaswini

    2016-09-01

    Full Text Available Interventional MRI in closed bore high-field systems is a challenge due to limited space and the need of dedicated MRI compatible equipment and tools. A possible solution could be to perform an ultrasound procedure for guidance of the therapy tools outside the bore, but still on the MRI patient bed. That could track and subsequently combine the superior images of MRI with the real-time features of ultrasound. Conventional optical tracking systems suffer from line of sight issues and electromagnetic tracking does not perform well in the presence of magnetic fields. Hence, to overcome these issues a new optical tracking system called inside-out tracking is used. In this approach, the camera is directly attached to the US probe and the markers are placed onto the patient to achieve the location information of the US slice. The evaluation of our novel system of framed fusion markers can easily be adapted to various imaging modalities without losing image registration. To confirm this evaluation, phantom studies with MRI and US imaging were carried out using a point-registration algorithm along with a similarity measure for fusion. In the inside-out system approach, image registration was found to yield an accuracy of upto 4 mm, depending on the imaging modality and the employed marker arrangement and with that provides an accuracy that cannot be easily achieved by combining pre-operative MRI with live ultrasound.

  5. Trajectory Tracking Control of Underactuated USV with Model Perturbation and External Interference

    Directory of Open Access Journals (Sweden)

    Liu Jinbiao

    2016-01-01

    Full Text Available This paper presents an improved trajectory tracking controller based backstepping control algorithm to address the trajectory tracking problem of an underactuated Unmanned Surface Vessel (USV. A Three Degree of Freedom (DOF underactuated maneuvering motion model for water-jet-propelled USV is established, and controller can track both straight line trajectory and curve trajectory with relatively high accuracy. The stability of USV system is proved by BIBO (bounded-input-bounded-output stable characteristics, then simulation experiments are carried out to demonstrate the robustness and precise control performance of the controller.

  6. Chattering-Free Adaptive Sliding Mode Control for Attitude Tracking of Spacecraft with External Disturbance

    Directory of Open Access Journals (Sweden)

    Xuxi Zhang

    2014-01-01

    Full Text Available The attitude tracking problem of spacecraft in the presence of unknown disturbance is investigated. By using the adaptive control technique and the Lyapunov stability theory, a chattering-free adaptive sliding mode control law is proposed for the attitude tracking problem of spacecraft with unknown disturbance. Simulation results are employed to demonstrate the effectiveness of the proposed control design technique in this paper.

  7. Marker-less systems for tracking working postures--results from two experiments.

    Science.gov (United States)

    Pinzke, S; Kopp, L

    2001-10-01

    Two experiments are performed to examine the usability of different marker-less approaches in image analysis and computer vision for automatic registration of OWAS (Ovako working posture analysing system) postures from video film. In experiment 1, a parametric method based on image analysis routines is developed both for separating the subject from its background and for relating the shapes of the extracted subject to OWAS postures. All 12 analysed images were correctly classified by the method. In experiment 2 a computer neural network is taught to relate postures of a subject to OWAS postures. When the network was trained with 53 images the rest of the set of 138 images was correctly classified. The experiments described in this paper show promising results regarding the use of image analysis and computer vision for tracking and assessing working postures. However, further research is needed including tests of different human models, neural networks, and template matching for making the OWAS method more useful in identifying and evaluating potentially harmful working postures.

  8. External quality assessment of tumour marker analysis: state of the art and consequences for estimating diagnostic sensitivity and specificity

    Directory of Open Access Journals (Sweden)

    Wood, William Graham

    2005-05-01

    Full Text Available This review shows the current analytical quality for the following analytes used as tumour markers in the external quality assessment (EQA-programmes of Instand e.V., a national EQA-organiser in Germany: Corticotropin (ACTH, growth hormone (GH, hGH, prolactin (PRL, chorionic gonadotropin (CG, hCG, calcitonin (CT, hCT, thyroglobulin (Tg, carcinoembryonic antigen (CEA, CA-Antigens 125, 72-4, 15-3 and 19-9, alpha foetoprotein (AFP and prostate-specific antigen (PSA. The results from the participants show a large variation in the precision of the methods used as well as in the comparability of results between methods for the same analyte. In general, the hormones used as tumour markers show better performance than the "CA-markers", which are often inadequately standardised and defined. In the case of one CA-marker (CA 72-4/TAG 72-4, the differences between the lowest kit median concentration and highest kit median concentration for one sample pair were 440% and 580%. The corresponding figures for ACTH were 123% and 156% and for CEA 180% and 184%. The classical tumour markers such as carcinoembryonic antigen (CEA and alpha foetoprotein (AFP performed markedly better than the CA-markers and PSA with regards to both inter- and intra-method comparability. The inter-laboratory precision for a given kit and marker was acceptable in many cases. The results show that only results from the same kit/method for each tumour marker can be used for cumulative or time-dependent comparison of results - for example pre-operative and post-operative follow up. In the case of prostate specific antigen (PSA, the kits used for free and total PSA must come from the same producer, if the generally accepted ratios are to have any diagnostic value. The need for kit- and laboratory-specific reference ranges and cut-off values for setting diagnostic specificity and sensitivity is highlighted from the EQA-results. The situation for inter-method comparability for the CA-Markers

  9. Automatic Thresholding for Frame-Repositioning Using External Tracking in PET Brain Imaging

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Keller, Sune; Sibomana, Merence

    2010-01-01

    Motion correction (MC) in positron emission tomography (PET) brain imaging become of higher importance with increasing scanner resolution. Several motion correction methods have been suggested and so far the Polaris Vicra tracking system has been the preferred one for motion registration. We pres...

  10. Stereoscopic representation of the breast from two mammographic view with external markers

    Science.gov (United States)

    Kallergi, Maria; Manohar, Anand

    2003-05-01

    A new breast imaging technique has been develoepd and tested for the stereoscopic representation of the breast. The method uses markers at specific locations on the breast surface and standard mammographic projections and was tested with an anthropomorphic phantom containing five mass-like objects at locations determined by a CT scan. The phantom was imaged with a GE Senographe 2000D digital system with and without the markers. The algorithm's modules included: 1) Breast area segmentation; 2) Pectoral muscle segmentation; 3) Registration and alignment of the mammographic projections based on selected reference points; 4) Breast volume estimation basdd on volume conservation principle during compression and shape definition using surface points; 5) 3D lesion(s) localization and representation. An interactive, ILD-based, graphical interface was also developed for the stereoscopic display of the breast. The reconstruction algorithm assumed that the breast shrinks and stretches uniformly when compression is applied and removed. The relative movement of the markers after compression allowed more accurate estimation of the shrinking and stretching of the surface offering a relatively simple and practical way to improve volume estimation and surface reconstruction. Such stereoscopic representation of the breast and associated findings may improve radiological interpretation and physical examinations for breast cancer diagnosis.

  11. Fecal pollution source tracking in waters intended for human supply based on archaeal and bacterial genetic markers.

    Science.gov (United States)

    Bianco, Kayo; Barreto, Camila; Oliveira, Samara Sant'Anna; Pinto, Leonardo Henriques; Albano, Rodolpho Mattos; Miranda, Catia Chaia; Clementino, Maysa Mandetta

    2015-12-01

    The determination of fecal pollution sources in aquatic ecosystems is essential to estimate associated health risks. In this study, we evaluate eight microbial source tracking (MST) markers including host-specific Bacteroidales and Methanobrevibacter spp. for discrimination between human, bovine, equine, and swine fecal contamination in waters intended for human supply. Overall, the novel host-specific archaeal and bacterial primers proposed in this study demonstrated high sensitivity and specificity. Markers for the Archaea domain were more prevalent in the fecal and water samples studied. We conclude that the investigations regarding the sources of fecal pollution in public water supplies can contribute to improve the quality of human health. To our knowledge, this is the first analysis using both archaeal and bacterial fecal MST markers on tropical water bodies of Rio de Janeiro city, Brazil.

  12. Utility of Microbial Source-Tracking Markers for Assessing Fecal Contamination in the Portage River Watershed, Northwestern Ohio, 2008

    Science.gov (United States)

    Kephart, Christopher M.; Bushon, Rebecca N.

    2010-01-01

    An influx of concentrated animal feeding operations in northwest Ohio has prompted local agencies to examine the effects of these industrial farms on water quality in the upper Portage River watershed. The utility of microbial source-tracking (MST) tools as a means of characterizing sources of fecal contamination in the watershed was evaluated. From 2007 to 2008, scientists with the U.S. Geological Survey, Bowling Green State University, and the Wood County Health Department collected and analyzed 17 environmental samples and 13 fecal source samples for Bacteroides-based host-associated DNA markers. At many of the environmental sites tested, MST marker results corroborated the presumptive fecal contamination sources. Results from this demonstration study support the utility of using MST with host-specific molecular markers to characterize the sources of fecal contamination in the Portage River watershed.

  13. [External changes of the face soft tissues as a marker of degenerative changes in collagen].

    Science.gov (United States)

    Vereshchaka, V V

    2013-01-01

    It was examined 120 persons of both sexes who had some problems with face skin. It was investigated the degree of face age changes in persons with the symptoms of skin slacses and practically healthy persons of different ages. Some methods of investigation were involved: computer analysis of photo graphes usingthe programmes of systemic face investigation in the combined stereocamera with optic device; it was involved semiquantity estimation of age skin changes which was introduced by us. Skin wrinkle creation is the reaction of collagene on the dose tention in soft tissues of the face and it is connected with compensatore reactions of collagen earchitectonicp reservation. Traditional articulatore movements create conditions for wrinkle development. Mimic muscule contraction lead to the wrinkle development which are determined in genetic level. External factors, particulatory solar radiation is the induction factor of wrinkle degree.

  14. Towards an Evaluation of Air Surveillance Track Clustering Algorithms via External Cluster Quality Measures

    Science.gov (United States)

    2013-01-01

    output. This function is referred to as PRM (for "Peak Rolling Mean") in the following table. By combining these track separation measures with the...9.39 5 1055 Mean-60k 60 km 403 10.28 5 858 Mean-70k 70 km 369 11.62 6 712 Mean-80k Simple Mean n/a 80 km 350 12.54 6 611 PRM :50-30k 30 km 427...7.49 4 1801 PRM :50-40k 40 km 375 6.79 4 2454 PRM :50-50k 50 km 405 7.06 4 2139 PRM :50-60k 60 km 412 7.46 4 1928 PRM :50-70k 70 km 427 7.76 4 1685

  15. Evaluation of five microbial and four mitochondrial DNA markers for tracking human and pig fecal pollution in freshwater

    Science.gov (United States)

    He, Xiwei; Liu, Peng; Zheng, Guolu; Chen, Huimei; Shi, Wei; Cui, Yibin; Ren, Hongqiang; Zhang, Xu-Xiang

    2016-10-01

    This study systematically evaluated five microbial and four mitochondrial DNA (mtDNA) markers, including sensitivities and specificities under PCR method, and fecal concentrations and decay rates in water under qPCR method. The microbial DNA markers were the three human-associated (BacH, HF183 and B.adolescentis) and two pig-associated (Pig-2-Bac and L.amylovorus), while the mtDNA ones were two human- (H-ND6 and H-ND5) and two pig-associated (P-CytB and P-ND5). All the mtDNA markers showed higher sensitivity (100%) than the microbial ones (84.0-88.8%) except Pig-2-Bac (100%). Specificities of the human mtDNA markers (99.1 and 98.1%) were higher than those of the human-associated microbial ones (57.0-88.8%). But this pattern was not observed in the pig-associated markers where Pig-2-Bac had 100% specificity. The reliability of H-ND6 and H-ND5 was further evidenced to identify locations of the most polluted within the Taihu Lake watershed of China. In general, the microbial DNA markers demonstrated a higher fecal concentration than the mtDNA ones; increasing temperature and sunlight exposure accelerated significantly the decay of all the DNA markers. Results of this study suggest that DNA markers H-ND6, H-ND5, and Pig-2-Bac may be among the best for fecal source tracking in water.

  16. Tracking tumor boundary in MV-EPID images without implanted markers: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaoyong, E-mail: xiaoyong@ieee.org; Homma, Noriyasu, E-mail: homma@ieee.org [Department of Radiological Imaging and Informatics, Tohoku University Graduate School of Medicine, Sendai 980-8579 (Japan); Ichiji, Kei, E-mail: ichiji@yoshizawa.ecei.tohoku.ac.jp [Research Institute of Electrical Communication, Tohoku University, Sendai 980-8579 (Japan); Takai, Yoshihiro, E-mail: y-takai@cc.hirosaki-u.ac.jp [Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562 (Japan); Yoshizawa, Makoto, E-mail: yoshizawa@yoshizawa.ecei.tohoku.ac.jp [Research Division on Advanced Information Technology, Cyberscience Center, Tohoku University, Sendai 980-8579 (Japan)

    2015-05-15

    Purpose: To develop a markerless tracking algorithm to track the tumor boundary in megavoltage (MV)-electronic portal imaging device (EPID) images for image-guided radiation therapy. Methods: A level set method (LSM)-based algorithm is developed to track tumor boundary in EPID image sequences. Given an EPID image sequence, an initial curve is manually specified in the first frame. Driven by a region-scalable energy fitting function, the initial curve automatically evolves toward the tumor boundary and stops on the desired boundary while the energy function reaches its minimum. For the subsequent frames, the tracking algorithm updates the initial curve by using the tracking result in the previous frame and reuses the LSM to detect the tumor boundary in the subsequent frame so that the tracking processing can be continued without user intervention. The tracking algorithm is tested on three image datasets, including a 4-D phantom EPID image sequence, four digitally deformable phantom image sequences with different noise levels, and four clinical EPID image sequences acquired in lung cancer treatment. The tracking accuracy is evaluated based on two metrics: centroid localization error (CLE) and volume overlap index (VOI) between the tracking result and the ground truth. Results: For the 4-D phantom image sequence, the CLE is 0.23 ± 0.20 mm, and VOI is 95.6% ± 0.2%. For the digital phantom image sequences, the total CLE and VOI are 0.11 ± 0.08 mm and 96.7% ± 0.7%, respectively. In addition, for the clinical EPID image sequences, the proposed algorithm achieves 0.32 ± 0.77 mm in the CLE and 72.1% ± 5.5% in the VOI. These results demonstrate the effectiveness of the authors’ proposed method both in tumor localization and boundary tracking in EPID images. In addition, compared with two existing tracking algorithms, the proposed method achieves a higher accuracy in tumor localization. Conclusions: In this paper, the authors presented a feasibility study of tracking

  17. Tracking neuronal marker expression inside living differentiating cells using molecular beacons

    DEFF Research Database (Denmark)

    Ilieva, Mirolyuba; Della Vedova, Paolo; Hansen, Ole

    2013-01-01

    Monitoring gene expression is an important tool for elucidating mechanisms of cellular function. In order to monitor gene expression during nerve cell development, molecular beacon (MB) probes targeting markers representing different stages of neuronal differentiation were designed and synthesized...

  18. Probabilistic analysis showing that a combination of bacteroides and methanobrevibacter source tracking markers is effective for identifying waters contaminated by human fecal pollution

    Science.gov (United States)

    Johnston, Christopher; Byappanahalli, Muruleedhara N.; Gibson, Jacqueline MacDonald; Ufnar, Jennifer A.; Whitman, Richard L.; Stewart, Jill R.

    2013-01-01

    Microbial source tracking assays to identify sources of waterborne contamination typically target genetic markers of host-specific microorganisms. However, no bacterial marker has been shown to be 100% host-specific, and cross-reactivity has been noted in studies evaluating known source samples. Using 485 challenge samples from 20 different human and animal fecal sources, this study evaluated microbial source tracking markers including the Bacteroides HF183 16S rRNA, M. smithii nifH, and Enterococcus esp gene targets that have been proposed as potential indicators of human fecal contamination. Bayes' Theorem was used to calculate the conditional probability that these markers or a combination of markers can correctly identify human sources of fecal pollution. All three human-associated markers were detected in 100% of the sewage samples analyzed. Bacteroides HF183 was the most effective marker for determining whether contamination was specifically from a human source, and greater than 98% certainty that contamination was from a human source was shown when both Bacteroides HF183 and M. smithii nifH markers were present. A high degree of certainty was attained even in cases where the prior probability of human fecal contamination was as low as 8.5%. The combination of Bacteroides HF183 and M. smithii nifH source tracking markers can help identify surface waters impacted by human fecal contamination, information useful for prioritizing restoration activities or assessing health risks from exposure to contaminated waters.

  19. Probabilistic analysis showing that a combination of Bacteroides and Methanobrevibacter source tracking markers is effective for identifying waters contaminated by human fecal pollution.

    Science.gov (United States)

    Johnston, Christopher; Byappanahalli, Muruleedhara N; Gibson, Jacqueline MacDonald; Ufnar, Jennifer A; Whitman, Richard L; Stewart, Jill R

    2013-01-01

    Microbial source tracking assays to identify sources of waterborne contamination typically target genetic markers of host-specific microorganisms. However, no bacterial marker has been shown to be 100% host-specific, and cross-reactivity has been noted in studies evaluating known source samples. Using 485 challenge samples from 20 different human and animal fecal sources, this study evaluated microbial source tracking markers including the Bacteroides HF183 16S rRNA, M. smithii nifH, and Enterococcus esp gene targets that have been proposed as potential indicators of human fecal contamination. Bayes' Theorem was used to calculate the conditional probability that these markers or a combination of markers can correctly identify human sources of fecal pollution. All three human-associated markers were detected in 100% of the sewage samples analyzed. Bacteroides HF183 was the most effective marker for determining whether contamination was specifically from a human source, and greater than 98% certainty that contamination was from a human source was shown when both Bacteroides HF183 and M. smithii nifH markers were present. A high degree of certainty was attained even in cases where the prior probability of human fecal contamination was as low as 8.5%. The combination of Bacteroides HF183 and M. smithii nifH source tracking markers can help identify surface waters impacted by human fecal contamination, information useful for prioritizing restoration activities or assessing health risks from exposure to contaminated waters.

  20. Music Preferences, Friendship, and Externalizing Behavior in Early Adolescence: A SIENA Examination of the Music Marker Theory Using the SNARE Study.

    Science.gov (United States)

    Franken, Aart; Keijsers, Loes; Dijkstra, Jan Kornelis; Ter Bogt, Tom

    2017-01-18

    Music Marker Theory posits that music is relevant for the structuring of peer groups and that rock, urban, or dance music preferences relate to externalizing behavior. The present study tested these hypotheses, by investigating the role of music preference similarity in friendship selection and the development of externalizing behavior, while taking the effects of friends' externalizing behavior into account. Data were used from the first three waves of the SNARE (Social Network Analysis of Risk behavior in Early adolescence) study (N = 1144; 50% boys; M age = 12.7; SD = 0.47), including students who entered the first-year of secondary school. Two hypotheses were tested. First, adolescents were expected to select friends based both on a similarity in externalizing behavior and music genre preference. Second, a preference for rock, urban, or dance, music types was expected to predict the development of externalizing behavior, even when taking friends' influence on externalizing behavior into account. Stochastic Actor-Based Modeling indicated that adolescents select their friends based on both externalizing behavior and highbrow music preference. Moreover, both friends' externalizing behavior and a preference for dance music predicted the development of externalizing behavior. Intervention programs might focus on adolescents with dance music preferences.

  1. Music preferences, friendship, and externalizing behavior in early adolescence : A SIENA examination of the music marker theory using the SNARE Study

    NARCIS (Netherlands)

    Franken, Aart; Keijsers, L.G.M.T.; Dijkstra, Jan Kornelis; Ter Bogt, Tom

    2017-01-01

    Music Marker Theory posits that music is relevant for the structuring of peer groups and that rock, urban, or dance music preferences relate to externalizing behavior. The present study tested these hypotheses, by investigating the role of music preference similarity in friendship selection and the

  2. Music preferences, friendship, and externalizing behavior in early adolescence : A SIENA examination of the music marker theory using the SNARE Study

    NARCIS (Netherlands)

    Franken, Aart; Keijsers, Loes; Dijkstra, Jan Kornelis; Ter Bogt, Tom

    2017-01-01

    Music Marker Theory posits that music is relevant for the structuring of peer groups and that rock, urban, or dance music preferences relate to externalizing behavior. The present study tested these hypotheses, by investigating the role of music preference similarity in friendship selection and the

  3. Pathogenic bacteria and microbial-source tracking markers in Brandywine Creek Basin, Pennsylvania and Delaware, 2009-10

    Science.gov (United States)

    Duris, Joseph W.; Reif, Andrew G.; Olson, Leif E.; Johnson, Heather E.

    2011-01-01

    virulent type of pathogenic E. coli, was found only in the West Branch and main stem at high flow but was not found in the East Branch under similar conditions. However, it must be noted that throughout the entire year of sampling there were occasions, during both high and normal flows, when both the East and West Branches were potential contributors of pathogen and microbial-source tracking markers to the main stem. Therefore, this study indicates that under selected conditions (high flow, October through March), West Branch Brandywine Creek Basin was the most likely source of elevated FIB densities in the main stem. These elevated densities are associated with more frequent detection of selected pathogenic E. coli markers (rfbO157 stx1) and are associated with MST markers of bovine source. However, during other times of the year, both the West Branch and East Branch Basins are acting as potential sources of FIB and fecally derived pathogens.

  4. Suitability and use of two molecular markers to track race-specific ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-07-08

    Jul 8, 2015 ... The obligate root parasitic weed Striga gesnerioides poses a severe constraint to cowpea productivity in the .... Recently, there are increasing interests in studies aiming at the molecular ... Faso, and present in IT82D-849; and six AFLP markers associated ... 25 µl PCR ready mix (Sigma-Aldrich) had18 µl of.

  5. Combined kV and MV imaging for real-time tracking of implanted fiducial markers.

    Science.gov (United States)

    Wiersma, R D; Mao, Weihua; Xing, L

    2008-04-01

    In the presence of intrafraction organ motion, target localization uncertainty can greatly hamper the advantage of highly conformal dose techniques such as intensity modulated radiation therapy (IMRT). To minimize the adverse dosimetric effect caused by tumor motion, a real-time knowledge of the tumor position is required throughout the beam delivery process. The recent integration of onboard kV diagnostic imaging together with MV electronic portal imaging devices on linear accelerators can allow for real-time three-dimensional (3D) tumor position monitoring during a treatment delivery. The aim of this study is to demonstrate a near real-time 3D internal fiducial tracking system based on the combined use of kV and MV imaging. A commercially available radiotherapy system equipped with both kV and MV imaging systems was used in this work. A hardware video frame grabber was used to capture both kV and MV video streams simultaneously through independent video channels at 30 frames per second. The fiducial locations were extracted from the kV and MV images using a software tool. The geometric tracking capabilities of the system were evaluated using a pelvic phantom with embedded fiducials placed on a moveable stage. The maximum tracking speed of the kV/MV system is approximately 9 Hz, which is primarily limited by the frame rate of the MV imager. The geometric accuracy of the system is found to be on the order of less than 1 mm in all three spatial dimensions. The technique requires minimal hardware modification and is potentially useful for image-guided radiation therapy systems.

  6. Age- and fatigue-related markers of human faces: an eye-tracking study.

    Science.gov (United States)

    Nguyen, Huy Tu; Isaacowitz, Derek M; Rubin, Peter A D

    2009-02-01

    To investigate the facial cues that are used when making judgments about how old or tired a face appears. Experimental study. Forty-seven subjects: 15 male and 32 female participants, ranging from age 18 to 30 years. Forty-eight full-face digital images of "normal-appearing" patients were collected and uploaded to an eye-tracking system. We used an Applied Science Laboratories (Bedford, MA) Eye Tracker device associated with gaze-tracking software to record and calculate the gaze and fixation of the participants' left eye as they viewed images on a computer screen. After seeing each picture, participants were asked to assess the age of the face in the picture by making a selection on a rating scale divided into 5-year intervals; for fatigue judgments we used a rating scale from 1 (not tired) to 7 (most tired). The main outcome measure was gaze fixation, as assessed by tracking the eye movements of participants as they viewed full-face digital pictures. For fatigue judgments, participants spent the most time looking at the eye region (31.81%), then the forehead and the nose regions (14.99% and 14.12%, respectively); in the eye region, participants looked most at the brows (13.1%) and lower lids (9.4%). Participants spent more time looking at the cheeks on faces they rated as least tired than they did on those they rated as most tired (t = 2.079, Peye region (27.22%) and then the forehead (15.71%) and the nose (14.30%) had the highest frequencies of interest; in the eye region, the brows and lower lids also had the highest frequencies of interest (11.40% and 8.90%, respectively). Participants looked more at the brows (t = -2.63, Peye region. Consequently, these results suggest that aesthetic or functional surgery to the eye region may be one of the most effective interventions in enhancing the appearance of an individual. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

  7. Relative Vessel Motion Tracking using Sensor Fusion, Aruco Markers, and MRU Sensors

    Directory of Open Access Journals (Sweden)

    Sondre Sanden Tordal

    2017-04-01

    Full Text Available This paper presents a novel approach for estimating the relative motion between two moving offshore vessels. The method is based on a sensor fusion algorithm including a vision system and two motion reference units (MRUs. The vision system makes use of the open-source computer vision library OpenCV and a cube with Aruco markers placed onto each of the cube sides. The Extended Quaternion Kalman Filter (EQKF is used for bad pose rejection for the vision system. The presented sensor fusion algorithm is based on the Indirect Feedforward Kalman Filter for error estimation. The system is self-calibrating in the sense that the Aruco cube can be placed in an arbitrary location on the secondary vessel. Experimental 6-DOF results demonstrate the accuracy and efficiency of the proposed sensor fusion method compared with the internal joint sensors of two Stewart platforms and the industrial robot. The standard deviation error was found to be 31mm or better when the Arcuo cube was placed at three different locations.

  8. Tracking growth hormone abuse in sport: performance of marker proteins in a controlled setting.

    Science.gov (United States)

    Bosch, J; Such-Sanmartín, G; Segura, J; Gutiérrez-Gallego, R

    2012-10-01

    Human growth hormone (hGH) abuse in sport is a challenge at present. The current strategy used, known as direct method, is based on the quantification of hGH variants in serum. An alternative strategy, known as indirect method, focuses on serum markers such as insulin-like growth factor I (IGF-I) and procollagen type III N-terminal propeptide (P-III-NP). The indirect method allows a longer window of detection (WOO) of hGH abuse. To evaluate the performance of the indirect method, in parallel to the direct method, a clinical trial with recombinant hGH (rhGH) was conducted on healthy male subjects during 7 days (0.026 mg(-1) kg(-1) person(-1) day(-1)). The data were fit to the discriminant formula proposed in the previously published GH-2000 project. The low sensitivity of the scores, judged from the high number of false negative outcomes, imposed a new discriminant analysis, standarised using local population subjects demographically similar to the ones of the study. The sensitivity of the method significantly increased, highlighting the importance of the standardisation. The indirect method allowed extended window of opportunity (WOO), although two false positive evaluations were observed derived from elevated basal IGF-I and P-III-NP concentrations stressing the need for an independent confirmation method. When direct and indirect methods were combined the best selectivity and sensitivity were achieved.

  9. Postprostatectomy ultrasound-guided transrectal implantation of gold markers for external beam radiotherapy. Technique and complications rate

    Energy Technology Data Exchange (ETDEWEB)

    Langenhuijsen, J.F.; Kiemeney, L.A.L.M.; Witjes, J.A. [Radboud Univ. Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Urology; Donker, R. [Medical Center Alkmaar (Netherlands). Dept. of Radiation Oncology; McColl, G.M.; Lin, E.N.J.T. van [Radboud Univ. Nijmegen Medical Center, Nijmegen (Netherlands). Dept. of Radiation Oncology

    2013-06-15

    Background and purpose: Postprostatectomy radiotherapy (RT) improves survival in adjuvant and salvage settings. The implantation technique and complications rate of gold markers in the prostate bed for high-precision RT were analyzed. Patients and methods: Patients undergoing postprostatectomy RT for prostate-specific antigen (PSA) relapse or high-risk disease were enrolled in the study. Under transrectal ultrasound guidance, three fine gold markers were implanted in the prostate bed and the technical difficulties of insertion were documented. Patients received our self-designed questionnaires concerning complications and pain. The influence of anticoagulants and coumarins on bleeding was analyzed, as was the effect of potential risk factors on pain. Results: In 77 consecutive patients, failure of marker implantation or marker migration was seen in six cases. Rectal bleeding was reported by 10 patients and 1 had voiding complaints. No macroscopic hematuria persisting for more than 3 days was observed. Other complications included rectal discomfort (n = 2), nausea (n = 1), abdominal discomfort (n = 1), and pain requiring analgesics (n = 4). No major complications were reported. On a 0-10 visual analogue scale (VAS), the mean pain score was 3.7. No clinically significant risk factors for complications were identified. Conclusion: Transrectal implantation of gold markers in the prostate bed is feasible and safe. Alternatives like cone beam computed tomography (CBCT) should be considered, but the advantages of gold marker implantation for high-precision postprostatectomy RT would seem to outweigh the minor risks involved. (orig.)

  10. Presence of microbial and chemical source tracking markers in roof-harvested rainwater and catchment systems for the detection of fecal contamination.

    Science.gov (United States)

    Waso, M; Ndlovu, T; Dobrowsky, P H; Khan, S; Khan, W

    2016-09-01

    Microbial source tracking (MST) and chemical source tracking (CST) markers were utilized to identify fecal contamination in harvested rainwater and gutter debris samples. Throughout the sampling period, Bacteroides HF183 was detected in 57.5 % of the tank water samples and 95 % of the gutter debris samples, while adenovirus was detected in 42.5 and 52.5 % of the tank water and gutter debris samples, respectively. Human adenovirus was then detected at levels ranging from below the detection limit to 316 and 1253 genome copies/μL in the tank water and debris samples, respectively. Results for the CST markers showed that salicylic acid (average 4.62 μg/L) was the most prevalent marker (100 %) in the gutter debris samples, caffeine (average 18.0 μg/L) was the most prevalent in the tank water samples (100 %) and acetaminophen was detected sporadically throughout the study period. Bacteroides HF183 and salicylic acid (95 %) and Bacteroides HF183 and caffeine (80 %) yielded high concurrence frequencies in the gutter debris samples. In addition, the highest concurrence frequency in the tank water samples was observed for Bacteroides HF183 and caffeine (60 %). The current study thus indicates that Bacteroides HF183, salicylic acid and caffeine may potentially be applied as source tracking markers in rainwater catchment systems in order to supplement fecal indicator analyses.

  11. SU-E-J-42: Evaluation of Fiducial Markers for Ultrasound and X-Ray Images Used for Motion Tracking in Pancreas SBRT

    Energy Technology Data Exchange (ETDEWEB)

    Ng, SK; Armour, E; Su, L; Zhang, Y; Wong, J; Ding, K [Department of Radiation Oncology, Johns Hopkins University, Baltimore, MD (United States); Iordachita, I [Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD (United States); Sen, H Tutkun; Kazanzides, P; Bell, M Lediju [Department of Computer Science, Johns Hopkins University, Baltimore, MD (United States)

    2015-06-15

    Purpose Ultrasound tracking of target motion relies on visibility of vascular and/or anatomical landmark. However this is challenging when the target is located far from vascular structures or in organs that lack ultrasound landmark structure, such as in the case of pancreas cancer. The purpose of this study is to evaluate visibility, artifacts and distortions of fusion coils and solid gold markers in ultrasound, CT, CBCT and kV images to identify markers suitable for real-time ultrasound tracking of tumor motion in SBRT pancreas treatment. Methods Two fusion coils (1mm × 5mm and 1mm × 10 mm) and a solid gold marker (0.8mm × 10mm) were embedded in a tissue–like ultrasound phantom. The phantom (5cm × 12cm × 20cm) was prepared using water, gelatin and psyllium-hydrophilic-mucilloid fiber. Psylliumhydrophilic mucilloid acts as scattering medium to produce echo texture that simulates sonographic appearance of human tissue in ultrasound images while maintaining electron density close to that of water in CT images. Ultrasound images were acquired using 3D-ultrasound system with markers embedded at 5, 10 and 15mm depth from phantom surface. CT images were acquired using Philips Big Bore CT while CBCT and kV images were acquired with XVI-system (Elexta). Visual analysis was performed to compare visibility of the markers and visibility score (1 to 3) were assigned. Results All markers embedded at various depths are clearly visible (score of 3) in ultrasound images. Good visibility of all markers is observed in CT, CBCT and kV images. The degree of artifact produced by the markers in CT and CBCT images are indistinguishable. No distortion is observed in images from any modalities. Conclusion All markers are visible in images across all modalities in this homogenous tissue-like phantom. Human subject data is necessary to confirm the marker type suitable for real-time ultrasound tracking of tumor motion in SBRT pancreas treatment.

  12. An Eye Tracking Comparison of External Pointing Cues and Internal Continuous Cues in Learning with Complex Animations

    Science.gov (United States)

    Boucheix, Jean-Michel; Lowe, Richard K.

    2010-01-01

    Two experiments used eye tracking to investigate a novel cueing approach for directing learner attention to low salience, high relevance aspects of a complex animation. In the first experiment, comprehension of a piano mechanism animation containing spreading-colour cues was compared with comprehension obtained with arrow cues or no cues. Eye…

  13. An Eye Tracking Comparison of External Pointing Cues and Internal Continuous Cues in Learning with Complex Animations

    Science.gov (United States)

    Boucheix, Jean-Michel; Lowe, Richard K.

    2010-01-01

    Two experiments used eye tracking to investigate a novel cueing approach for directing learner attention to low salience, high relevance aspects of a complex animation. In the first experiment, comprehension of a piano mechanism animation containing spreading-colour cues was compared with comprehension obtained with arrow cues or no cues. Eye…

  14. Piezo activated mode tracking system for widely tunable mode-hop-free external cavity mid-IR semiconductor lasers

    Science.gov (United States)

    Wysocki, Gerard (Inventor); Tittel, Frank K. (Inventor); Curl, Robert F. (Inventor)

    2010-01-01

    A widely tunable, mode-hop-free semiconductor laser operating in the mid-IR comprises a QCL laser chip having an effective QCL cavity length, a diffraction grating defining a grating angle and an external cavity length with respect to said chip, and means for controlling the QCL cavity length, the external cavity length, and the grating angle. The laser of claim 1 wherein said chip may be tuned over a range of frequencies even in the absence of an anti-reflective coating. The diffraction grating is controllably pivotable and translatable relative to said chip and the effective QCL cavity length can be adjusted by varying the injection current to the chip. The laser can be used for high resolution spectroscopic applications and multi species trace-gas detection. Mode-hopping is avoided by controlling the effective QCL cavity length, the external cavity length, and the grating angle so as to replicate a virtual pivot point.

  15. A new tool fixation for external 3D head tracking using the Polaris Vicra system with the HRRT PET scanner

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Andersen, Flemming; Holm, Søren;

    Objectives: The Polaris Vicra system (Northern Digital Inc.) is used for external 3D head registration with the Siemens HRRT brain PET. Our new tool fixation using a standard bandaid with a velcro-strap implies an improved frame repositioning. Methods: Head movements during serial PET 15O-water s...

  16. Feasibility of two-dimensional speckle tracking in evaluation of arterial stiffness: Comparison with pulse wave velocity and conventional sonographic markers of atherosclerosis.

    Science.gov (United States)

    Podgórski, Michał; Grzelak, Piotr; Kaczmarska, Magdalena; Polguj, Michał; Łukaszewski, Maciej; Stefańczyk, Ludomir

    2017-01-01

    Objective Arterial stiffening is an early marker of atherosclerosis that has a prognostic value for cardiovascular morbidity and mortality. Although many markers of arterial hardening have been proposed, the search is on for newer, more user-friendly and reliable surrogates. One such potential candidate has emerged from cardiology, the speckle-tracking technique. The aim of this study was to evaluate the feasibility of the two-dimensional speckle tracking for the evaluation of arterial wall stiffness in comparison with standard stiffness parameters. Methods Carotid ultrasound and applanation tonometry were performed in 188 patients with no cardiovascular risk factors. The following parameters were then evaluated: the intima-media complex thickness, distensibility coefficient, β-stiffness index, circumferential strain/strain rate, and pulse wave velocity and augmentation index. These variables were compared with each other and with patient age, and their reliability was assessed with Bland-Altman plots. Results Strain parameters derived from two-dimensional speckle tracking and intima-media complex thickness correlated better with age and pulse wave velocity than standard makers of arterial stiffness. Moreover, the reliability of these measurements was significantly higher than conventional surrogates. Conclusions Two-dimensional speckle tracing is a reliable method for the evaluation of arterial stiffness. Therefore, together with intima-media complex thickness measurement, it offers great potential in clinical practice as an early marker of atherosclerosis.

  17. Development of microsatellite markers in Gonystylus bancanus (Ramin) useful for tracing and tracking of wood of this protected species

    NARCIS (Netherlands)

    Smulders, M.J.M.; Westende, van 't W.P.C.; Diway, B.; Esselink, G.D.; Meer, van der P.J.; Koopman, W.J.M.

    2008-01-01

    Ten polymorphic microsatellite markers have been developed for Gonystylus bancanus (Ramin), a protected tree species of peat swamp forests in Malaysia and Indonesia. Eight markers were also shown to be polymorphic in other Gonystylus species. The markers will enable assessing the amount of genetic v

  18. Transperineal gold marker implantation for image-guided external beam radiotherapy of prostate cancer. A single institution, prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Jorgo, Kliton; Agoston, Peter; Major, Tibor; Takacsi-Nagy, Zoltan; Polgar, Csaba [National Institute of Oncology, Centre of Radiotherapy, Budapest (Hungary)

    2017-06-15

    To present the feasibility and complications of transperineal fiducial marker implantation in prostate cancer patients undergoing image-guided radiotherapy (IGRT) Between November 2011 and April 2016, three radiopaque, gold-plated markers were transperineally implanted into the prostate of 300 patients under transrectal ultrasound guidance and with local anaesthesia. A week after the procedure patients filled in a questionnaire regarding pain, dysuria, urinary frequency, nocturia, rectal bleeding, hematuria, hematospermia or fever symptoms caused by the implantation. Pain was scored on a 1-10 scale, where score 1 meant very weak and score 10 meant unbearable pain. The implanted gold markers were used for daily verification and online correction of patients' setup during IGRT. Based on the questionnaires no patient experienced fever, infection, dysuria or rectal bleeding after implantation. Among the 300 patients, 12 (4%) had hematospermia, 43 (14%) hematuria, which lasted for an average of 3.4 and 1.8 days, respectively. The average pain score was 4.6 (range 0-9). Of 300 patients 87 (29%) felt any pain after the intervention, which took an average of 1.5 days. None of the patients needed analgesics after implantation. Overall, 105 patients (35%) reported less, 80 patients (27%) more, and 94 patients (31%) equal amount of pain during marker implantation compared to biopsy. The 21 patients who had a biopsy performed under general anesthesia did not answer this question. Transperineal gold marker implantation under local anesthesia was well tolerated. Complications were limited; rate and frequency of perioperative pain was comparable to the pain caused by biopsy. The method can be performed safely in clinical practice. (orig.) [German] Darstellung von Machbarkeit und Komplikationen der transperinealen Implantation von Goldmarkern bei mit perkutaner Strahlentherapie (IGRT) behandelten Prostatakarzinompatienten. Zwischen November 2011 und April 2016 bekamen 300

  19. Adaptive Radiation Therapy for Postprostatectomy Patients Using Real-Time Electromagnetic Target Motion Tracking During External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Mingyao [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Bharat, Shyam [Philips Research North America, Briarcliff Manor, New York (United States); Michalski, Jeff M.; Gay, Hiram A. [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Hou, Wei-Hsien [St Louis University School of Medicine, St Louis, Missouri (United States); Parikh, Parag J., E-mail: pparikh@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States)

    2013-03-15

    Purpose: Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in postprostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Methods and Materials: Tracking data recorded by Calypso EM transponders was analyzed for postprostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (D{sub min}) with the planned D{sub min} to the CTV. Treatments were considered adequate if the delivered CTV D{sub min} is at least 95% of the planned CTV D{sub min}. Results: Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: −0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5°, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Conclusion: Target rotational motion could cause underdosage to partial volume of the postprostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery.

  20. Adaptive Radiation Therapy for Post-Prostatectomy Patients Using Real-Time Electromagnetic Target Motion Tracking During External Beam Radiotherapy

    Science.gov (United States)

    Zhu, Mingyao; Bharat, Shyam; Michalski, Jeff M.; Gay, H; Hou, Wei-Hsien; Parikh, Parag J.

    2012-01-01

    Purpose Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso® 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in post-prostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Methods and Materials Tracking data recorded by Calypso EM transponders was analyzed for post-prostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (Dmin) with the planned Dmin to the CTV. Treatments were considered adequate if the delivered CTV Dmin is at least 95% of the planned CTV Dmin. Results Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: − 0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5 degrees, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Conclusion Target rotational motion could cause under-dosage to partial volume of the post-prostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery. PMID:23021439

  1. Adaptive radiation therapy for postprostatectomy patients using real-time electromagnetic target motion tracking during external beam radiation therapy.

    Science.gov (United States)

    Zhu, Mingyao; Bharat, Shyam; Michalski, Jeff M; Gay, Hiram A; Hou, Wei-Hsien; Parikh, Parag J

    2013-03-15

    Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in postprostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Tracking data recorded by Calypso EM transponders was analyzed for postprostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (Dmin) with the planned Dmin to the CTV. Treatments were considered adequate if the delivered CTV Dmin is at least 95% of the planned CTV Dmin. Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: -0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5°, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Target rotational motion could cause underdosage to partial volume of the postprostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Simulation of magnetic drug targeting through tracheobronchial airways in the presence of an external non-uniform magnetic field using Lagrangian magnetic particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Pourmehran, O., E-mail: oveis87@yahoo.com; Rahimi-Gorji, M.; Gorji-Bandpy, M., E-mail: gorji@nit.ac.ir; Gorji, T.B.

    2015-11-01

    Drug delivery technologies are an important area within biomedicine. Targeted drug delivery aims to reduce the undesired side effects of drug usage by directing or capturing the active agents near a desired site within the body. Herein, a numerical investigation of magnetic drug targeting (MDT) using aerosol drugs named polystyrene particle (PMS40) in human lung is presented considering one-way coupling on the transport and capture of the magnetic particle. A realistic 3D geometry based on CT scan images is provided for CFD simulation. An external non-uniform magnetic field is applied. Parametric investigation is conducted and the influence of particle diameter, magnetic source position, and magnetic number (Mn) on the deposition efficiency and particle behavior is reported. According to the results, the magnetic field increased deposition efficiency of particles in a target region, the efficiency of deposition and MDT technique has a direct relation with increasing the particle diameter for magnetic number of 1 Tesla (T) and lower (Mn≤1(T)). Also it can be seen that there is an inverse relation between the particle diameter and deposition efficiency when Mn is more than 1 (T). - Highlights: • A realistic 3D geometry of human tracheobronchial airway based on CT scan image. • External non-uniform magnetic field applied to target the magnetic drug career. • Lagrangian particle tracking using discrete phase model applied. • The efficiency of deposition is dependent of magnetic number and particle diameter.

  3. Development and validation of a microbial source tracking marker for the detection of fecal pollution by muskrats.

    Science.gov (United States)

    Marti, Romain; Zhang, Yun; Lapen, David R; Topp, Edward

    2011-10-01

    Surface waters in mixed-activity watersheds can be compromised by fecal pollution from livestock production, sewage outflows or leaking septic systems, or avian or mammalian wildlife. While undertaking water quality research in Eastern Ontario Canada, we observed an abundance of muskrats (Ondatra zibethicus) in some waterways, and sought to determine their significance with respect to fecal pollution loads. To that end, we developed and validated here a sensitive and specific marker, designated MuBa01, based on the 16S rRNA gene that distinguishes muskrat feces from human, livestock, or other wildlife sources. DNA from waterways inhabited by muskrats carried the marker. The widely used pig-specific marker Pig-2-Bac yielded a product with some muskrat feces, suggesting that it lacks specificity required to establish the significance of swine production in areas inhabited by muskrats. Overall, the MuBa01 marker will be useful for distinguishing the significance of this wide-ranging semi-aquatic mammal in the context of other fecal pollution sources.

  4. Transesophageal Echocardiography, 3-Dimensional and Speckle Tracking Together as Sensitive Markers for Early Outcome in Patients With Left Ventricular Dysfunction Undergoing Cardiac Surgery.

    Science.gov (United States)

    Kumar, Alok; Puri, Goverdhan Dutt; Bahl, Ajay

    2017-10-01

    Speckle tracking, when combined with 3-dimensional (3D) left ventricular ejection fraction, might prove to be a more sensitive marker for postoperative ventricular dysfunction. This study investigated early outcomes in a cohort of patients with left ventricular dysfunction undergoing cardiac surgery. Prospective, blinded, observational study. University hospital; single institution. The study comprised 73 adult patients with left ventricular ejection fraction speckle tracking and 3D left ventricular ejection fraction were computed using transesophageal echocardiography. Mean prebypass global longitudinal strain and 3D left ventricle ejection fraction were significantly lower in patients with postoperative low-cardiac-output syndrome compared with patients who did not develop low cardiac output (global longitudinal strain -7.5% v -10.7% and 3D left ventricular ejection fraction 29% v 39%, respectively; p < 0.0001). The cut-off value of global longitudinal strain predicting postoperative low-cardiac-output syndrome was -6%, with 95% sensitivity and 68% specificity; and 3D left ventricular ejection fraction was 19% with 98% sensitivity and 81% specificity. Preoperative left ventricular global longitudinal strain (-6%) and 3D left ventricular ejection fraction (19%) together could act as predictor of postoperative low-cardiac-output states with high sensitivity (99.9%) in patients undergoing cardiac surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. A Study on Stereoscopic X-ray Imaging Data Set on the Accuracy of Real-Time Tumor Tracking in External Beam Radiotherapy.

    Science.gov (United States)

    Esmaili Torshabi, Ahmad; Ghorbanzadeh, Leila

    2017-04-01

    At external beam radiotherapy, stereoscopic X-ray imaging system is responsible as tumor motion information provider. This system takes X-ray images intermittently from tumor position (1) at pretreatment step to provide training data set for model construction and (2) during treatment to control the accuracy of correlation model performance. In this work, we investigated the effect of imaging data points provided by this system on treatment quality. Because some information is still lacking about (1) the number of imaging data points, (2) shooting time for capturing each data point, and also (3) additional imaging dose delivered by this system. These 3 issues were comprehensively assessed at (1) pretreatment step while training data set is gathered for prediction model construction and (2) during treatment while model is tested and reconstructed using new arrival data points. A group of real patients treated with CyberKnife Synchrony module was chosen in this work, and an adaptive neuro-fuzzy inference system was considered as consistent correlation model. Results show that a proper model can be constructed while the number of imaging data points is highly enough to represent a good pattern of breathing cycles. Moreover, a trade-off between the number of imaging data points and additional imaging dose is considered in this study. Since breathing phenomena are highly variable at different patients, the time for taking some of imaging data points is very important, while their absence at that critical time may yield wrong tumor tracking. In contrast, the sensitivity of another category of imaging data points is not high, while breathing is normal and in the control range. Therefore, an adaptive supervision on the implementation of stereoscopic X-ray imaging is proposed to intelligently accomplish shooting process, based on breathing motion variations.

  6. The dopamine receptor D4 gene and familial loading interact with perceived parenting in predicting externalizing behavior problems in early adolescence: the TRacking Adolescents' Individual Lives Survey (TRAILS)

    NARCIS (Netherlands)

    Marsman, R.; Oldehinkel, A.J.; Ormel, J.; Buitelaar, J.K.

    2013-01-01

    Although externalizing behavior problems show in general a high stability over time, the course of externalizing behavior problems may vary from individual to individual. Our main goal was to investigate the predictive role of parenting on externalizing behavior problems. In addition, we investigate

  7. The dopamine receptor D4 gene and familial loading interact with perceived parenting in predicting externalizing behavior problems in early adolescence : The TRacking Adolescents' Individual Lives Survey (TRAILS)

    NARCIS (Netherlands)

    Marsman, Rianne; Oldehinkel, Albertine J.; Ormel, Johan; Buitelaar, Jan K.

    2013-01-01

    Although externalizing behavior problems show in general a high stability over time, the course of externalizing behavior problems may vary from individual to individual. Our main goal was to investigate the predictive role of parenting on externalizing behavior problems. In addition, we investigate

  8. Tracking the expression of excitatory and inhibitory neurotransmission-related proteins and neuroplasticity markers after noise induced hearing loss.

    Directory of Open Access Journals (Sweden)

    Cherylea J Browne

    Full Text Available Excessive exposure to loud noise can damage the cochlea and create a hearing loss. These pathologies coincide with a range of CNS changes including reorganisation of frequency representation, alterations in the pattern of spontaneous activity and changed expression of excitatory and inhibitory neurotransmitters. Moreover, damage to the cochlea is often accompanied by acoustic disorders such as hyperacusis and tinnitus, suggesting that one or more of these neuronal changes may be involved in these disorders, although the mechanisms remain unknown. We tested the hypothesis that excessive noise exposure increases expression of markers of excitation and plasticity, and decreases expression of inhibitory markers over a 32-day recovery period. Adult rats (n = 25 were monaurally exposed to a loud noise (16 kHz, 1/10(th octave band pass (115 dB SPL for 1-hour, or left as non-exposed controls (n = 5. Animals were euthanased at either 0, 4, 8, 16 or 32 days following acoustic trauma. We used Western Blots to quantify protein levels of GABA(A receptor subunit α1 (GABA(Aα1, Glutamic-Acid Decarboxylase-67 (GAD-67, N-Methyl-D-Aspartate receptor subunit 2A (NR2A, Calbindin (Calb1 and Growth Associated Protein 43 (GAP-43 in the Auditory Cortex (AC, Inferior Colliculus (IC and Dorsal Cochlear Nucleus (DCN. Compared to sham-exposed controls, noise-exposed animals had significantly (p<0.05: lower levels of GABA(Aα1 in the contralateral AC at day-16 and day-32, lower levels of GAD-67 in the ipsilateral DCN at day-4, lower levels of Calb1 in the ipsilateral DCN at day-0, lower levels of GABA(Aα1 in the ipsilateral AC at day-4 and day-32. GAP-43 was reduced in the ipsilateral AC for the duration of the experiment. These complex fluctuations in protein expression suggests that for at least a month following acoustic trauma the auditory system is adapting to a new pattern of sensory input.

  9. 基于标记点检测的视线跟踪注视点估计%Eye Tracking Gaze Estimation Based on Marker Detection

    Institute of Scientific and Technical Information of China (English)

    龚秀锋; 李斌; 邓宏平; 张文聪

    2011-01-01

    For head-mounted eye gaze tracking, additional head position sensors is needed to determine the gaze direction, a new method based on marker detection is proposed to estimate the gaze of point for head-mounted system in this paper.The markers are detected by computer vision method, and the relationship between scene image and computer screen is constructed with point correspondences in two views.The point of gaze in the scene image is translated to computer screen coordinate.Experimental result shows that this method can estimate the point of gaze in real scene easily irrespective of user's head position.%传统的头戴式视线跟踪系统需要借助额外的头部位置跟踪器或其他辅助设备才能定位视线方向.针对该问题,提出一种基于标记点检测的注视点估计方法.该方法通过计算机视觉的方法检测标记点,建立场景图像与真实场景中计算机屏幕之间的空间关系,将场景图像中的注视点坐标映射到计算机屏幕中.实验结果表明,该方法简单易行,可以较好地估计出用户在真实场景中的注视点坐标.

  10. WE-AB-303-08: Direct Lung Tumor Tracking Using Short Imaging Arcs

    Energy Technology Data Exchange (ETDEWEB)

    Shieh, C; Huang, C; Keall, P; Feain, I [University of Sydney, Sydney (Australia)

    2015-06-15

    Purpose: Most current tumor tracking technologies rely on implanted markers, which suffer from potential toxicity of marker placement and mis-targeting due to marker migration. Several markerless tracking methods have been proposed: these are either indirect methods or have difficulties tracking lung tumors in most clinical cases due to overlapping anatomies in 2D projection images. We propose a direct lung tumor tracking algorithm robust to overlapping anatomies using short imaging arcs. Methods: The proposed algorithm tracks the tumor based on kV projections acquired within the latest six-degree imaging arc. To account for respiratory motion, an external motion surrogate is used to select projections of the same phase within the latest arc. For each arc, the pre-treatment 4D cone-beam CT (CBCT) with tumor contours are used to estimate and remove the contribution to the integral attenuation from surrounding anatomies. The position of the tumor model extracted from 4D CBCT of the same phase is then optimized to match the processed projections using the conjugate gradient method. The algorithm was retrospectively validated on two kV scans of a lung cancer patient with implanted fiducial markers. This patient was selected as the tumor is attached to the mediastinum, representing a challenging case for markerless tracking methods. The tracking results were converted to expected marker positions and compared with marker trajectories obtained via direct marker segmentation (ground truth). Results: The root-mean-squared-errors of tracking were 0.8 mm and 0.9 mm in the superior-inferior direction for the two scans. Tracking error was found to be below 2 and 3 mm for 90% and 98% of the time, respectively. Conclusions: A direct lung tumor tracking algorithm robust to overlapping anatomies was proposed and validated on two scans of a lung cancer patient. Sub-millimeter tracking accuracy was observed, indicating the potential of this algorithm for real-time guidance

  11. A novel mouse model for non-invasive single marker tracking of mammary stem cells in vivo reveals stem cell dynamics throughout pregnancy.

    Directory of Open Access Journals (Sweden)

    Benjamin J Tiede

    Full Text Available Mammary stem cells (MaSCs play essential roles for the development of the mammary gland and its remodeling during pregnancy. However, the precise localization of MaSCs in the mammary gland and their regulation during pregnancy is unknown. Here we report a transgenic mouse model for luciferase-based single marker detection of MaSCs in vivo that we used to address these issues. Single transgene expressing mammary epithelial cells were shown to reconstitute mammary glands in vivo while immunohistochemical staining identified MaSCs in basal and luminal locations, with preponderance towards the basal position. By quantifying luciferase expression using bioluminescent imaging, we were able to track MaSCs non-invasively in individual mice over time. Using this model to monitor MaSC dynamics throughout pregnancy, we found that MaSCs expand in both total number and percentage during pregnancy and then drop down to or below baseline levels after weaning. However, in a second round of pregnancy, this expansion was not as extensive. These findings validate a powerful system for the analysis of MaSC dynamics in vivo, which will facilitate future characterization of MaSCs during mammary gland development and breast cancer.

  12. Performing gait analysis within the timed up & go assessment test: comparison of aTUG to a marker-based tracking system.

    Science.gov (United States)

    Frenken, Thomas; Lohmann, Okko; Frenken, Melina; Steen, Enno-Edzard; Hein, Andreas

    2014-01-01

    Results from a technical validation of the aTUG (ambient Timed Up & Go) system are presented. The approach's gait analysis capabilities were compared to a gold standard: SIMI Motion, a marker-based motion tracking system. Seven people participated and computation of step length and step duration happened with a median error of 3 cm (IQR 3 cm) respectively 0.08 s (IQR 0.07 s). These results show that aTUG has a measurement precision which is sufficient for use in clinical gait analysis and enables the use of the device without a gold standard, i.e. in hospitals outside laboratories or in the homes of patients. aTUG is an approach and system that utilizes only ambient sensor technologies to support the execution of geriatric mobility assessment tests and to perform a gait analysis simultaneously. Such capabilities are strongly demanded in order to support physicians in executing the geriatric assessment tests frequently and objectively in professional and domestic environments. The latter may enable more early prevention and more sustainable rehabilitation.

  13. Differential denudations of the Argentera Alpine external crystalline massif (SE France) revealed by fission track thermo-chronology (zircons, apatites); Denudations differentielles du massif cristallin externe alpin de l'Argentera (Sud-Est de la France) revelees par thermochronologie traces de fission (apatites, zircons)

    Energy Technology Data Exchange (ETDEWEB)

    Bigot-Cormier, F.; Sosson, M. [Centre National de la Recherche Scientifique (CNRS-UMR 6526), Geosciences Azur, 06 - Valbonne (France); Poupeau, G. [Maison des Geosciences, 38 - Grenoble (France)

    2000-03-01

    A fission track thermo-chronological study of the Argentera external crystalline massif (western Alps) reveals tectonic blocks with differential vertical motions. The northwest area cooled down about 300 deg. C from the Upper Cretaceous and the remaining of the massif crossed the 250 deg. C isotherm in the 29-20 Ma time interval, after the internal nappe over-thrust. Moreover the massif cooled below 120 deg. C more than 12.5 Ma ago and its denudation rate increased locally 6 Ma ago and more generally since 3.5 Ma in relation with the reverse motion along the Bersezio fault. (authors)

  14. Effects of divorce on Dutch boys' and girls' externalizing behavior in Gene × Environment perspective: diathesis stress or differential susceptibility in the Dutch Tracking Adolescents' Individual Lives Survey study?

    Science.gov (United States)

    Nederhof, Esther; Belsky, Jay; Ormel, Johan; Oldehinkel, Albertine J

    2012-08-01

    The effects of divorce on children's behavioral development have proven to be quite varied across studies, and most developmental and family scholars today appreciate the great heterogeneity in divorce effects. Thus, this inquiry sought to determine whether select dopaminergic genes previously associated with externalizing behavior and/or found to moderate diverse environmental effects (dopamine receptors D2 and D4, catechol-O-methyltransferase) might moderate divorce effects on adolescent self-reported externalizing problems; and, if so, whether evidence of gene-environment (G × E) interaction would prove consistent with diathesis-stress or differential-susceptibility models of environmental action. Data from the first and third wave of the Dutch Tracking Adolescents' Individual Lives Survey (n = 1,134) revealed some evidence of G × E interaction reflecting diathesis-stress but not differential susceptibility. It is intriguing that some evidence pointed to "vantage sensitivity," which are benefits accruing to those with a specific genotype when their parents remained together, the exact opposite of diathesis-stress. The limits of this work are considered, especially with regard to the conditions for testing differential susceptibility, and future directions are outlined.

  15. Outcome prediction after mild and complicated mild traumatic brain injury: external validation of existing models and identification of new predictors using the TRACK-TBI pilot study.

    Science.gov (United States)

    Lingsma, Hester F; Yue, John K; Maas, Andrew I R; Steyerberg, Ewout W; Manley, Geoffrey T

    2015-01-15

    Although the majority of patients with mild traumatic brain injury (mTBI) recover completely, some still suffer from disabling ailments at 3 or 6 months. We validated existing prognostic models for mTBI and explored predictors of poor outcome after mTBI. We selected patients with mTBI from TRACK-TBI Pilot, an unselected observational cohort of TBI patients from three centers in the United States. We validated two prognostic models for the Glasgow Outcome Scale Extended (GOS-E) at 6 months after injury. One model was based on the CRASH study data and another from Nijmegen, The Netherlands. Possible predictors of 3- and 6-month GOS-E were analyzed with univariate and multi-variable proportional odds regression models. Of the 386 of 485 patients included in the study (median age, 44 years; interquartile range, 27-58), 75% (n=290) presented with a Glasgow Coma Score (GCS) of 15. In this mTBI population, both previously developed models had a poor performance (area under the receiver operating characteristic curve, 0.49-0.56). In multivariable analyses, the strongest predictors of lower 3- and 6-month GOS-E were older age, pre-existing psychiatric conditions, and lower education. Injury caused by assault, extracranial injuries, and lower GCS were also predictive of lower GOS-E. Existing models for mTBI performed unsatisfactorily. Our study shows that, for mTBI, different predictors are relevant as for moderate and severe TBI. These include age, pre-existing psychiatric conditions, and lower education. Development of a valid prediction model for mTBI patients requires further research efforts.

  16. Outcome Prediction after Mild and Complicated Mild Traumatic Brain Injury: External Validation of Existing Models and Identification of New Predictors Using the TRACK-TBI Pilot Study

    Science.gov (United States)

    Lingsma, Hester F.; Yue, John K.; Maas, Andrew I.R.; Steyerberg, Ewout W.; Cooper, Shelly R.; Dams-O'Connor, Kristen; Gordon, Wayne A.; Menon, David K.; Mukherjee, Pratik; Okonkwo, David O.; Puccio, Ava M.; Schnyer, David M.; Valadka, Alex B.; Vassar, Mary J.; Yuh, Esther L.

    2015-01-01

    Abstract Although the majority of patients with mild traumatic brain injury (mTBI) recover completely, some still suffer from disabling ailments at 3 or 6 months. We validated existing prognostic models for mTBI and explored predictors of poor outcome after mTBI. We selected patients with mTBI from TRACK-TBI Pilot, an unselected observational cohort of TBI patients from three centers in the United States. We validated two prognostic models for the Glasgow Outcome Scale Extended (GOS-E) at 6 months after injury. One model was based on the CRASH study data and another from Nijmegen, The Netherlands. Possible predictors of 3- and 6-month GOS-E were analyzed with univariate and multi-variable proportional odds regression models. Of the 386 of 485 patients included in the study (median age, 44 years; interquartile range, 27–58), 75% (n=290) presented with a Glasgow Coma Score (GCS) of 15. In this mTBI population, both previously developed models had a poor performance (area under the receiver operating characteristic curve, 0.49–0.56). In multivariable analyses, the strongest predictors of lower 3- and 6-month GOS-E were older age, pre-existing psychiatric conditions, and lower education. Injury caused by assault, extracranial injuries, and lower GCS were also predictive of lower GOS-E. Existing models for mTBI performed unsatisfactorily. Our study shows that, for mTBI, different predictors are relevant as for moderate and severe TBI. These include age, pre-existing psychiatric conditions, and lower education. Development of a valid prediction model for mTBI patients requires further research efforts. PMID:25025611

  17. Real time noninvasive assessment of external trunk geometry during surgical correction of adolescent idiopathic scoliosis

    Directory of Open Access Journals (Sweden)

    Mac-Thiong Jean-Marc

    2009-02-01

    Full Text Available Abstract Background The correction of trunk deformity is crucial in scoliosis surgery, especially for the patient's self-image. However, direct visualization of external scoliotic trunk deformity during surgical correction is difficult due to the covering draping sheets. Methods An optoelectronic camera system with 10 passive markers is used to track the trunk geometry of 5 scoliotic patients during corrective surgery. The position of 10 anatomical landmarks and 5 trunk indices computed from the position of the passive markers are compared during and after instrumentation of the spine. Results Internal validation of the accuracy of tracking was evaluated at 0.41 +/- 0.05 mm RMS. Intra operative tracking during surgical maneuvers shows improvement of the shoulder balance during and after correction of the spine. Improvement of the overall patient balance is observed. At last, a minor increase of the spinal length can be noticed. Conclusion Tracking of the external geometry of the trunk during surgical correction is useful to monitor changes occurring under the sterile draping sheets. Moreover, this technique can used be used to reach the optimal configuration on the operating frame before proceeding to surgery. The current tracking technique was able to detect significant changes in trunk geometry caused by posterior instrumentation of the spine despite significant correction of the spinal curvature. It could therefore become relevant for computer-assisted guidance of surgical maneuvers when performing posterior instrumentation of the scoliotic spine, provide important insights during positioning of patients.

  18. Optimal marker placement in hadrontherapy: intelligent optimization strategies with augmented Lagrangian pattern search.

    Science.gov (United States)

    Altomare, Cristina; Guglielmann, Raffaella; Riboldi, Marco; Bellazzi, Riccardo; Baroni, Guido

    2015-02-01

    In high precision photon radiotherapy and in hadrontherapy, it is crucial to minimize the occurrence of geometrical deviations with respect to the treatment plan in each treatment session. To this end, point-based infrared (IR) optical tracking for patient set-up quality assessment is performed. Such tracking depends on external fiducial points placement. The main purpose of our work is to propose a new algorithm based on simulated annealing and augmented Lagrangian pattern search (SAPS), which is able to take into account prior knowledge, such as spatial constraints, during the optimization process. The SAPS algorithm was tested on data related to head and neck and pelvic cancer patients, and that were fitted with external surface markers for IR optical tracking applied for patient set-up preliminary correction. The integrated algorithm was tested considering optimality measures obtained with Computed Tomography (CT) images (i.e. the ratio between the so-called target registration error and fiducial registration error, TRE/FRE) and assessing the marker spatial distribution. Comparison has been performed with randomly selected marker configuration and with the GETS algorithm (Genetic Evolutionary Taboo Search), also taking into account the presence of organs at risk. The results obtained with SAPS highlight improvements with respect to the other approaches: (i) TRE/FRE ratio decreases; (ii) marker distribution satisfies both marker visibility and spatial constraints. We have also investigated how the TRE/FRE ratio is influenced by the number of markers, obtaining significant TRE/FRE reduction with respect to the random configurations, when a high number of markers is used. The SAPS algorithm is a valuable strategy for fiducial configuration optimization in IR optical tracking applied for patient set-up error detection and correction in radiation therapy, showing that taking into account prior knowledge is valuable in this optimization process. Further work will be

  19. Quality assurance program of a respiratory gating irradiation system based on external and internal fiducial markers; Programa de garantia de calidad de un sistema de irradiacion con control respiratorio basado en marcadores fiduciales externos e internos

    Energy Technology Data Exchange (ETDEWEB)

    Zucca Aparicio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrilla, J.; Minambres Moro, A.

    2011-07-01

    Respiratory Gating involves the administration of radiation during treatment delivery within a particular portion of the patients breathing cycle, so the absorbed dose administration with respiratory control techniques requires specific quality control to ensure the correctness of the delivered dose. The establishment of a Quality Control Program (QC) is proposed for the Respiratory Gating based techniques in order to have a better understanding of how this system works and to know its associated dosimetric impact. The influence of the CT acquisition under respiratory motion conditions has been analyzed for the treatment isocenter localization, using internal and external fiducial markers with IGRT techniques that allow the correlation of the isocenter positioning with the phase of the respiratory cycle. Radiation delivery in the presence of intra fraction organ motion causes an averaging or blurring of the static dose distribution over the path of motion increasing the beam penumbra of the radiation field and reducing the therapeutic region when the irradiation is not breath controlled. The feasibility of intensity modulated treatments (IMRT) for both static and dynamic techniques, managed by respiratory control has been tested, demonstrating the possibility of synchronizing the movement of the leaves in the microfluorimeter collimator (mMLC) with the gated beam irradiation. (Author) 45 refs.

  20. Transgenic manipulation of plant embryo sacs tracked through cell-type-specific fluorescent markers: cell labeling, cell ablation, and adventitious embryos.

    Science.gov (United States)

    Lawit, Shai J; Chamberlin, Mark A; Agee, April; Caswell, Eric S; Albertsen, Marc C

    2013-06-01

    Expression datasets relating to the Arabidopsis female gametophyte have enabled the creation of a tool set which allows simultaneous visual tracking of each specific cell type (egg, synergids, central cell, and antipodals). This cell-specific, fluorescent labeling tool-set functions from gametophyte cellularization through fertilization and early embryo development. Using this system, cell fates were tracked within Arabidopsis ovules following molecular manipulations, such as the ablation of the egg and/or synergids. Upon egg cell ablation, it was observed that a synergid can switch its developmental fate to become egg/embryo-like upon loss of the native egg. Also, manipulated was the fate of the somatic ovular cells, which can become egg- and embryo-like, reminiscent of adventitious embryony. These advances represent initial steps toward engineering synthetic apomixis resulting in seed derived wholly from the maternal plant. The end goal of applied apomixis research, fixing important agronomic traits such as hybrid vigor, would be a key benefit to agricultural productivity.

  1. Internal-external correlation investigations of respiratory induced motion of lung tumors.

    Science.gov (United States)

    Ionascu, Dan; Jiang, Steve B; Nishioka, Seiko; Shirato, Hiroki; Berbeco, Ross I

    2007-10-01

    In gated radiation therapy procedures, the lung tumor position is used directly (by implanted radiopaque markers) or indirectly (by external surrogate methods) to decrease the volume of irradiated healthy tissue. Due to a risk of pneumothorax, many clinics do not implant fiducials, and the gated treatment is primarily based on a respiratory induced external signal. The external surrogate method relies upon the assumption that the internal tumor motion is well correlated with the external respiratory induced motion, and that this correlation is constant in time. Using a set of data that contains synchronous internal and external motion traces, we have developed a dynamic data analysis technique to study the internal-external correlation, and to quantitatively estimate its underlying time behavior. The work presented here quantifies the time dependent behavior of the correlation between external respiratory signals and lung implanted fiducial motion. The corresponding amplitude mismatch is also reported for the lung patients studied. The information obtained can be used to improve the accuracy of tumor tracking. For the ten patients in this study, the SI internal-external motion is well correlated, with small time shifts and corresponding amplitude mismatches. Although the AP internal-external motion reveals larger time shifts than along the SI direction, the corresponding amplitude mismatches are below 5 mm.

  2. ERIC-PCR fingerprinting-based community DNA hybridization to pinpoint genome-specific fragments as molecular markers to identify and track populations common to healthy human guts.

    Science.gov (United States)

    Wei, Guifang; Pan, Li; Du, Huimin; Chen, Junyi; Zhao, Liping

    2004-10-01

    Bacterial populations common to healthy human guts may play important roles in human health. A new strategy for discovering genomic sequences as markers for these bacteria was developed using Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR fingerprinting. Structural features within microbial communities are compared with ERIC-PCR followed by DNA hybridization to identify genomic fragments shared by samples from healthy human individuals. ERIC-PCR profiles of fecal samples from 12 diseased or healthy human and piglet subjects demonstrated stable, unique banding patterns for each individual tested. Sequence homology of DNA fragments in bands of identical size was examined between samples by hybridization under high stringency conditions with DIG-labeled ERIC-PCR products derived from the fecal sample of one healthy child. Comparative analysis of the hybridization profiles with the original agarose fingerprints identified three predominant bands as signatures for populations associated with healthy human guts with sizes of 500, 800 and 1000 bp. Clone library profiling of the three bands produced 17 genome fragments, three of which showed high similarity only with regions of the Bacteroides thetaiotaomicron genome, while the remainder were orphan sequences. Association of these sequences with healthy guts was validated by sequence-selective PCR experiments, which showed that a single fragment was present in all 32 healthy humans and 13 healthy piglets tested. Two fragments were present in the healthy human group and in 18 children with non-infectious diarrhea but not in eight children with infectious diarrhea. Genome fragments identified with this novel strategy may be used as genome-specific markers for dynamic monitoring and sequence-guided isolation of functionally important bacterial populations in complex communities such as human gut microflora.

  3. Tracking micro-optical resonances for identifying and sensing novel procaspase-3 protein marker released from cell cultures in response to toxins

    Science.gov (United States)

    Chen, Ying-Jen; Xiang, Wei; Klucken, Jochen; Vollmer, Frank

    2016-04-01

    The response of cells to toxins is commonly investigated by detecting intracellular markers for cell death, such as caspase proteins. This requires the introduction of labels by the permeabilization or complete lysis of cells. Here we introduce a non-invasive tool for monitoring a caspase protein in the extracellular medium. The tool is based on highly sensitive optical micro-devices, referred to as whispering-gallery mode biosensors (WGMBs). WGMBs are functionalized with antibodies for the specific and label-free detection of procaspase-3 released from human embryonic kidney HEK293 and neuroglioma H4 cells after introducing staurosporine and rotenone toxins, respectively. Additional tests show that the extracellular accumulation of procaspase-3 is concomitant with a decrease in cell viability. The hitherto unknown release of procaspase-3 from cells in response to toxins and its accumulation in the medium is further investigated by Western blot, showing that the extracellular detection of procaspase-3 is interrelated with cytotoxicity of alpha-synuclein protein (aSyn) overexpressed in H4 cells. These studies provide evidence for procaspase-3 as a novel extracellular biomarker for cell death, with applications in cytotoxicity tests. Such WGMBs could be applied to further identify as-yet unknown extracellular biomarkers using established antibodies against intracellular antigens.

  4. Comparison of Superparamagnetic and Ultrasmall Superparamagnetic Iron Oxide Cell Labeling for Tracking Green Fluorescent Protein Gene Marker with Negative and Positive Contrast Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Zhuoli Zhang

    2009-05-01

    Full Text Available The objectives of this study were to investigate the feasibility of imaging green fluorescent protein (GFP-expressing cells labeled with iron oxide nanoparticles with the fast low-angle positive contrast steady-state free precession (FLAPS method and to compare them with the traditional negative contrast technique. The GFP-R3230Ac cell line (GFP cell was incubated for 24 hours using 20 μg Fe/mL concentration of superparamagnetic iron oxide (SPIO and ultrasmall superparamagnetic iron oxide (USPIO nanoparticles. Cell samples were prepared for iron content analysis and cell function evaluation. The labeled cells were imaged using positive contrast with FLAPS imaging, and FLAPS images were compared with negative contrast T2*-weighted images. The results demonstrated that SPIO and USPIO labeling of GFP cells had no effect on cell function or GFP expression. Labeled cells were successfully imaged with both positive and negative contrast magnetic resonance imaging (MRI. The labeled cells were observed as a narrow band of signal enhancement surrounding signal voids in FLAPS images and were visible as signal voids in T2*-weighted images. Positive contrast and negative contrast imaging were both valuable for visualizing labeled GFP cells. MRI of labeled cells with GFP expression holds potential promise for monitoring the temporal and spatial migration of gene markers and cells, thereby enhancing the understanding of cell- and gene-based therapeutic strategies.

  5. AIRSHIP ATTITUDE TRACKING SYSTEM

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-liang; SHAN Xue-xiong

    2006-01-01

    The attitude tracking control problem for an airship with parameter uncertainties and external disturbances was considered in this paper. The mathematical model of the airship attitude is a multi-input/multi-output uncertain nonlinear system. Based on the characteristics of this system, a design method of robust output tracking controllers was adopted based on the upper-bounds of the uncertainties. Using the input/output feedback linearization approach and Liapunov method, a control law was designed, which guarantees that the system output exponentially tracks the given desired output. The controller is easy to compute and complement. Simulation results show that, in the closed-loop system, precise attitude control is accomplished in spite of the uncertainties and external disturbances in the system.

  6. Molecular marker applications in plants.

    Science.gov (United States)

    Hayward, Alice C; Tollenaere, Reece; Dalton-Morgan, Jessica; Batley, Jacqueline

    2015-01-01

    Individuals within a population of a sexually reproducing species will have some degree of heritable genomic variation caused by mutations, insertion/deletions (INDELS), inversions, duplications, and translocations. Such variation can be detected and screened using molecular, or genetic, markers. By definition, molecular markers are genetic loci that can be easily tracked and quantified in a population and may be associated with a particular gene or trait of interest. This chapter will review the current major applications of molecular markers in plants.

  7. An externally and internally deformable, programmable lung motion phantom

    Science.gov (United States)

    Cheung, Yam; Sawant, Amit

    2015-01-01

    Purpose: Most clinically deployed strategies for respiratory motion management in lung radiotherapy (e.g., gating and tracking) use external markers that serve as surrogates for tumor motion. However, typical lung phantoms used to validate these strategies are based on a rigid exterior and a rigid or a deformable-interior. Such designs do not adequately represent respiration because the thoracic anatomy deforms internally as well as externally. In order to create a closer approximation of respiratory motion, the authors describe the construction and experimental testing of an externally as well as internally deformable, programmable lung phantom. Methods: The outer shell of a commercially available lung phantom (RS-1500, RSD, Inc.) was used. The shell consists of a chest cavity with a flexible anterior surface, and embedded vertebrae, rib-cage and sternum. A custom-made insert was designed using a piece of natural latex foam block. A motion platform was programmed with sinusoidal and ten patient-recorded lung tumor trajectories. The platform was used to drive a rigid foam “diaphragm” that compressed/decompressed the phantom interior. Experimental characterization comprised of determining the reproducibility and the external–internal correlation of external and internal marker trajectories extracted from kV x-ray fluoroscopy. Experiments were conducted to illustrate three example applications of the phantom—(i) validating the geometric accuracy of the VisionRT surface photogrammetry system; (ii) validating an image registration tool, NiftyReg; and (iii) quantifying the geometric error due to irregular motion in four-dimensional computed tomography (4DCT). Results: The phantom correctly reproduced sinusoidal and patient-derived motion, as well as realistic respiratory motion-related effects such as hysteresis. The reproducibility of marker trajectories over multiple runs for sinusoidal as well as patient traces, as characterized by fluoroscopy, was within 0

  8. An externally and internally deformable, programmable lung motion phantom

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Yam; Sawant, Amit, E-mail: amit.sawant@utsouthwestern.edu [UT Southwestern Medical Center, University of Texas, Dallas, Texas 75390 (United States)

    2015-05-15

    Purpose: Most clinically deployed strategies for respiratory motion management in lung radiotherapy (e.g., gating and tracking) use external markers that serve as surrogates for tumor motion. However, typical lung phantoms used to validate these strategies are based on a rigid exterior and a rigid or a deformable-interior. Such designs do not adequately represent respiration because the thoracic anatomy deforms internally as well as externally. In order to create a closer approximation of respiratory motion, the authors describe the construction and experimental testing of an externally as well as internally deformable, programmable lung phantom. Methods: The outer shell of a commercially available lung phantom (RS-1500, RSD, Inc.) was used. The shell consists of a chest cavity with a flexible anterior surface, and embedded vertebrae, rib-cage and sternum. A custom-made insert was designed using a piece of natural latex foam block. A motion platform was programmed with sinusoidal and ten patient-recorded lung tumor trajectories. The platform was used to drive a rigid foam “diaphragm” that compressed/decompressed the phantom interior. Experimental characterization comprised of determining the reproducibility and the external–internal correlation of external and internal marker trajectories extracted from kV x-ray fluoroscopy. Experiments were conducted to illustrate three example applications of the phantom—(i) validating the geometric accuracy of the VisionRT surface photogrammetry system; (ii) validating an image registration tool, NiftyReg; and (iii) quantifying the geometric error due to irregular motion in four-dimensional computed tomography (4DCT). Results: The phantom correctly reproduced sinusoidal and patient-derived motion, as well as realistic respiratory motion-related effects such as hysteresis. The reproducibility of marker trajectories over multiple runs for sinusoidal as well as patient traces, as characterized by fluoroscopy, was within 0

  9. Magnetic Resonance Imaging–Guided versus Surrogate-Based Motion Tracking in Liver Radiation Therapy: A Prospective Comparative Study

    Energy Technology Data Exchange (ETDEWEB)

    Paganelli, Chiara, E-mail: chiara.paganelli@polimi.it [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Seregni, Matteo; Fattori, Giovanni [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Summers, Paul [Division of Radiology, Istituto Europeo di Oncologia, Milano (Italy); Bellomi, Massimo [Division of Radiology, Istituto Europeo di Oncologia, Milano (Italy); Department of Health Sciences, Università degli Studi di Milano, Milano (Italy); Baroni, Guido; Riboldi, Marco [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano (Italy); Bioengineering Unit, CNAO Foundation, Pavia (Italy)

    2015-03-15

    Purpose: This study applied automatic feature detection on cine–magnetic resonance imaging (MRI) liver images in order to provide a prospective comparison between MRI-guided and surrogate-based tracking methods for motion-compensated liver radiation therapy. Methods and Materials: In a population of 30 subjects (5 volunteers plus 25 patients), 2 oblique sagittal slices were acquired across the liver at high temporal resolution. An algorithm based on scale invariant feature transform (SIFT) was used to extract and track multiple features throughout the image sequence. The position of abdominal markers was also measured directly from the image series, and the internal motion of each feature was quantified through multiparametric analysis. Surrogate-based tumor tracking with a state-of-the-art external/internal correlation model was simulated. The geometrical tracking error was measured, and its correlation with external motion parameters was also investigated. Finally, the potential gain in tracking accuracy relying on MRI guidance was quantified as a function of the maximum allowed tracking error. Results: An average of 45 features was extracted for each subject across the whole liver. The multi-parametric motion analysis reported relevant inter- and intrasubject variability, highlighting the value of patient-specific and spatially-distributed measurements. Surrogate-based tracking errors (relative to the motion amplitude) were were in the range 7% to 23% (1.02-3.57mm) and were significantly influenced by external motion parameters. The gain of MRI guidance compared to surrogate-based motion tracking was larger than 30% in 50% of the subjects when considering a 1.5-mm tracking error tolerance. Conclusions: Automatic feature detection applied to cine-MRI allows detailed liver motion description to be obtained. Such information was used to quantify the performance of surrogate-based tracking methods and to provide a prospective comparison with respect to MRI

  10. Marker development

    Energy Technology Data Exchange (ETDEWEB)

    Adams, M.R.

    1987-05-01

    This report is to discuss the marker development for radioactive waste disposal sites. The markers must be designed to last 10,000 years, and place no undue burdens on the future generations. Barriers cannot be constructed that preclude human intrusion. Design specifications for surface markers will be discussed, also marker pictograms will also be covered.

  11. Prediction of 3D internal organ position from skin surface motion: results from electromagnetic tracking studies

    Science.gov (United States)

    Wong, Kenneth H.; Tang, Jonathan; Zhang, Hui J.; Varghese, Emmanuel; Cleary, Kevin R.

    2005-04-01

    An effective treatment method for organs that move with respiration (such as the lungs, pancreas, and liver) is a major goal of radiation medicine. In order to treat such tumors, we need (1) real-time knowledge of the current location of the tumor, and (2) the ability to adapt the radiation delivery system to follow this constantly changing location. In this study, we used electromagnetic tracking in a swine model to address the first challenge, and to determine if movement of a marker attached to the skin could accurately predict movement of an internal marker embedded in an organ. Under approved animal research protocols, an electromagnetically tracked needle was inserted into a swine liver and an electromagnetically tracked guidewire was taped to the abdominal skin of the animal. The Aurora (Northern Digital Inc., Waterloo, Canada) electromagnetic tracking system was then used to monitor the position of both of these sensors every 40 msec. Position readouts from the sensors were then tested to see if any of the movements showed correlation. The strongest correlations were observed between external anterior-posterior motion and internal inferior-superior motion, with many other axes exhibiting only weak correlation. We also used these data to build a predictive model of internal motion by taking segments from the data and using them to derive a general functional relationship between the internal needle and the external guidewire. For the axis with the strongest correlation, this model enabled us to predict internal organ motion to within 1 mm.

  12. Laser Marked Codes For Paperless Tracking Applications

    Science.gov (United States)

    Crater, David

    1987-01-01

    The application of laser markers for marking machine readable codes is described. Use of such codes for automatic tracking and considerations for marker performance and features are discussed. Available laser marker types are reviewed. Compatibility of laser/material combinations and material/code/reader systems are reviewed.

  13. A quantitative assessment of using the Kinect for Xbox 360 for respiratory surface motion tracking

    Science.gov (United States)

    Alnowami, M.; Alnwaimi, B.; Tahavori, F.; Copland, M.; Wells, K.

    2012-02-01

    This paper describes a quantitative assessment of the Microsoft Kinect for X-box360TM for potential application in tracking respiratory and body motion in diagnostic imaging and external beam radiotherapy. However, the results can also be used in many other biomedical applications. We consider the performance of the Kinect in controlled conditions and find mm precision at depths of 0.8-1.5m. We also demonstrate the use of the Kinect for monitoring respiratory motion of the anterior surface. To improve the performance of respiratory monitoring, we fit a spline model of the chest surface through the depth data as a method of a marker-less monitoring of a respiratory motion. In addition, a comparison between the Kinect camera with and without zoom lens and a marker-based system was used to evaluate the accuracy of using the Kinect camera as a respiratory tracking system.

  14. Marker chromosomes.

    Science.gov (United States)

    Rao, Kiran Prabhaker; Belogolovkin, Victoria

    2013-04-01

    Marker chromosomes are a morphologically heterogeneous group of structurally abnormal chromosomes that pose a significant challenge in prenatal diagnosis. Phenotypes associated with marker chromosomes are highly variable and range from normal to severely abnormal. Clinical outcomes are very difficult to predict when marker chromosomes are detected prenatally. In this review, we outline the classification, etiology, cytogenetic characterization, and clinical consequences of marker chromosomes, as well as practical approaches to prenatal diagnosis and genetic counseling.

  15. External Otitis (Swimmer's Ear)

    Science.gov (United States)

    ... to Pneumococcal Vaccine Additional Content Medical News External Otitis (Swimmer's Ear) By Bradley W. Kesser, MD, Associate ... the Outer Ear Ear Blockages Ear Tumors External Otitis (Swimmer's Ear) Malignant External Otitis Perichondritis External otitis ...

  16. Marker Detection in Aerial Images

    KAUST Repository

    Alharbi, Yazeed

    2017-04-09

    The problem that the thesis is trying to solve is the detection of small markers in high-resolution aerial images. Given a high-resolution image, the goal is to return the pixel coordinates corresponding to the center of the marker in the image. The marker has the shape of two triangles sharing a vertex in the middle, and it occupies no more than 0.01% of the image size. An improvement on the Histogram of Oriented Gradients (HOG) is proposed, eliminating the majority of baseline HOG false positives for marker detection. The improvement is guided by the observation that standard HOG description struggles to separate markers from negatives patches containing an X shape. The proposed method alters intensities with the aim of altering gradients. The intensity-dependent gradient alteration leads to more separation between filled and unfilled shapes. The improvement is used in a two-stage algorithm to achieve high recall and high precision in detection of markers in aerial images. In the first stage, two classifiers are used: one to quickly eliminate most of the uninteresting parts of the image, and one to carefully select the marker among the remaining interesting regions. Interesting regions are selected by scanning the image with a fast classifier trained on the HOG features of markers in all rotations and scales. The next classifier is more precise and uses our method to eliminate the majority of the false positives of standard HOG. In the second stage, detected markers are tracked forward and backward in time. Tracking is needed to detect extremely blurred or distorted markers that are missed by the previous stage. The algorithm achieves 94% recall with minimal user guidance. An average of 30 guesses are given per image; the user verifies for each whether it is a marker or not. The brute force approach would return 100,000 guesses per image.

  17. (SSR) markers

    African Journals Online (AJOL)

    SAM

    2014-07-30

    Jul 30, 2014 ... Simple sequence repeats (SSRs) are the most widely used marker system for plant variety characterization and ... gene tagging in marker assisted breeding and gene cloning in .... PLS-2 and PAU Selection Long) to 1.00 (between PC. 2062 and .... Comparative analyses of genetic diversities within tomato.

  18. (SSR) markers

    African Journals Online (AJOL)

    Yomi

    2012-04-03

    Apr 3, 2012 ... seeded and black-seeded cultivars and breeding lines. The group B included 70 ... maize, rice and tomatoes (Reif et al., 2006; Vigouroux et al., 2005; Warburton et ..... development of molecular markers for marker-assisted breeding. .... Selection under domestication: evidence for a sweep in the rice Waxy ...

  19. SU-C-BRF-05: Design and Geometric Validation of An Externally and Internally Deformable, Programmable Lung Motion Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Y; Sawant, A [UT Southwestern Medical Center, Dallas, TX (United States)

    2014-06-15

    Purpose: Most clinically-deployed strategies for respiratory motion management in lung radiotherapy (e.g., gating, tracking) use external markers that serve as surrogates for tumor motion. However, typical lung phantoms used to validate these strategies are rigid-exterior+rigid-interior or rigid-exterior+deformable-interior. Neither class adequately represents the human anatomy, which is deformable internally as well as externally. We describe the construction and experimental validation of a more realistic, externally- and internally-deformable, programmable lung phantom. Methods: The outer shell of a commercially-available lung phantom (RS- 1500, RSD Inc.) was used. The shell consists of a chest cavity with a flexible anterior surface, and embedded vertebrae, rib-cage and sternum. A 3-axis platform was programmed with sinusoidal and six patient-recorded lung tumor trajectories. The platform was used to drive a rigid foam ‘diaphragm’ that compressed/decompressed the phantom interior. Experimental characterization comprised of mapping the superior-inferior (SI) and anterior-posterior (AP) trajectories of external and internal radioopaque markers with kV x-ray fluoroscopy and correlating these with optical surface monitoring using the in-room VisionRT system. Results: The phantom correctly reproduced the programmed motion as well as realistic effects such as hysteresis. The reproducibility of marker trajectories over multiple runs for sinusoidal as well as patient traces, as characterized by fluoroscopy, was within 0.4 mm RMS error for internal as well as external markers. The motion trajectories of internal and external markers as measured by fluoroscopy were found to be highly correlated (R=0.97). Furthermore, motion trajectories of arbitrary points on the deforming phantom surface, as recorded by the VisionRT system also showed a high correlation with respect to the fluoroscopically-measured trajectories of internal markers (R=0.92). Conclusion: We have

  20. Unscented Kalman filtering for articulated human tracking

    DEFF Research Database (Denmark)

    Boesen Lindbo Larsen, Anders; Hauberg, Søren; Pedersen, Kim Steenstrup

    2011-01-01

    We present an articulated tracking system working with data from a single narrow baseline stereo camera. The use of stereo data allows for some depth disambiguation, a common issue in articulated tracking, which in turn yields likelihoods that are practically unimodal. While current state...... with superior results. Tracking quality is measured by comparing with ground truth data from a marker-based motion capture system....

  1. Bone Markers

    Science.gov (United States)

    ... markers may be seen in conditions such as: Osteoporosis Paget disease Cancer that has spread to the bone (metastatic bone disease) Hyperparathyroidism Hyperthyroidism Osteomalacia in adults and rickets in children—lack of bone mineralization, ...

  2. Sci—Sat AM: Stereo — 09: Accuracy of Liver Cancer Treatment on Cyberknife® with Synchrony™ Optical Tracking Throughout the Respiratory Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Winter, J.; Chow, T [Juravinski Cancer Center, Hamilton, Ontario (Canada); Wong, R.

    2014-08-15

    The Cyberknife® robotic stereotactic body radiation therapy system is well-suited for treating liver lesions over the respiratory cycle as it includes room-mounted orthogonal x-ray tracking of internal fiducial markers and optical tracking of external markers. The Synchrony™ software generates a model of internal target positions during patient respiration and correlates it to the external optical tracking system for real-time optical-based position corrections of the linear accelerator during beam delivery. Although clinical studies have provided preliminary outcomes for liver lesions treated with the Cyberknife system, to date, there is little data demonstrating the ability of the Synchrony software to track targets in the liver, which deforms throughout the respiratory cycle. In this study, we investigated the respiratory motion model performance for predicting tumour motion. We conducted a retrospective analysis of fifteen liver cancer patients treated on the Cyberknife using the Synchrony optical tracking system. We analyzed Cyberknife tracking information stored in the log files to extract the left-right (LR), anterior-posterior (AP) and superior-inferior (SI) correlation errors between the model-predicted position and the internal fiducial centroid position determined by x-ray imaging. Only translational tracking and corrections were applied during treatment. Overall, the correlation errors were greatest in the SI direction. We calculated radial correlation errors, and determined that the 95{sup th}, 98{sup th} and 99{sup th} percentile errors were 3.4 mm, 4.4 mm and 5.1 mm, respectively. Based on translational correlation tracking errors we expect the clinical target volume will be within 3.4 mm of the planning target volume for 95 % of beam delivery time.

  3. Printed Tag Real-time Tracking

    KAUST Repository

    Bilal, Rana M.

    2014-09-18

    Disclosed are various embodiments for monitoring tracking devices capable of seamless indoor and outdoor tracking transitions. A tracking device may comprise, for example, printable circuitry and antennas combined with one or more receivers/transceivers on a substrate. The tracking device may be configured, for example, to localize the tracking device via GPS or an alternative localization strategy based on a determination of whether GPS communication is available. A modified RSSI fingerprinting methodology may be used to accurately determine a location of the tracking device using Wi-Fi access points. A device monitoring service may communicate with internal and/or external mapping API\\'s to render a device monitoring user interface comprising a visual representation of the location of the tracking device.

  4. Handheld pose tracking using vision-inertial sensors with occlusion handling

    Science.gov (United States)

    Li, Juan; Slembrouck, Maarten; Deboeverie, Francis; Bernardos, Ana M.; Besada, Juan A.; Veelaert, Peter; Aghajan, Hamid; Casar, José R.; Philips, Wilfried

    2016-07-01

    Tracking of a handheld device's three-dimensional (3-D) position and orientation is fundamental to various application domains, including augmented reality (AR), virtual reality, and interaction in smart spaces. Existing systems still offer limited performance in terms of accuracy, robustness, computational cost, and ease of deployment. We present a low-cost, accurate, and robust system for handheld pose tracking using fused vision and inertial data. The integration of measurements from embedded accelerometers reduces the number of unknown parameters in the six-degree-of-freedom pose calculation. The proposed system requires two light-emitting diode (LED) markers to be attached to the device, which are tracked by external cameras through a robust algorithm against illumination changes. Three data fusion methods have been proposed, including the triangulation-based stereo-vision system, constraint-based stereo-vision system with occlusion handling, and triangulation-based multivision system. Real-time demonstrations of the proposed system applied to AR and 3-D gaming are also included. The accuracy assessment of the proposed system is carried out by comparing with the data generated by the state-of-the-art commercial motion tracking system OptiTrack. Experimental results show that the proposed system has achieved high accuracy of few centimeters in position estimation and few degrees in orientation estimation.

  5. The External Degree.

    Science.gov (United States)

    Houle, Cyril O.

    This book examines the external degree in relation to the extremes of attitudes, myths, and data. Emphasis is placed on the emergence of the American external degree, foreign external-degree programs, the purpose of the external degree, the current scene, institutional issues, and problems of general policy. (MJM)

  6. A Magnetic Tracking System based on Highly Sensitive Integrated Hall Sensors

    Science.gov (United States)

    Schlageter, Vincent; Drljaca, Predrag; Popovic, Radivoje S.; KuČERA, Pavel

    A tracking system with five degrees of freedom based on a 2D-array of 16 Hall sensors and a permanent magnet is presented in this paper. The sensitivity of the Hall sensors is increased by integrated micro- and external macro-flux-concentrators. Detection distance larger than 20cm (during one hour without calibration) is achieved using a magnet of 0.2cm3. This corresponds to a resolution of the sensors of 0.05µTrms. The position and orientation of the marker is displayed in real time at least 20 times per second. The sensing system is small enough to be hand-held and can be used in a normal environment. This presented tracking system has been successfully applied to follow a small swallowed magnet through the entire human digestive tube. This approach is extremely promising as a new non-invasive diagnostic technique in gastro-enterology.

  7. SU-E-J-156: Preclinical Inverstigation of Dynamic Tumor Tracking Using Vero SBRT Linear Accelerator: Motion Phantom Dosimetry Study

    Energy Technology Data Exchange (ETDEWEB)

    Mamalui-Hunter, M; Wu, J; Li, Z; Su, Z [University of Florida/Radiation Oncology, Jacksonville, FL (United States)

    2014-06-01

    Purpose: Following the ‘end-to-end testing’ paradigm of Dynamic Target Tracking option in our Image-Guided dedicated SBRT VeroTM linac, we verify the capability of the system to deliver planned dose to moving targets in the heterogeneous thorax phantom (CIRSTM). The system includes gimbaled C-band linac head, robotic 6 degree of freedom couch and a tumor tracking method based on predictive modeling of target position using fluoroscopically tracked implanted markers and optically tracked infrared reflecting external markers. Methods: 4DCT scan of the motion phantom with the VisicoilTM implanted marker in the close vicinity of the target was acquired, the ‘exhale’=most prevalent phase was used for planning (iPlan by BrainLabTM). Typical 3D conformal SBRT treatment plans aimed to deliver 6-8Gy/fx to two types of targets: a)solid water-equivalent target 3cm in diameter; b)single VisicoilTM marker inserted within lung equivalent material. The planning GTV/CTV-to-PTV margins were 2mm, the block margins were 3 mm. The dose calculated by MonteCarlo algorithm with 1% variance using option Dose-to-water was compared to the ion chamber (CC01 by IBA Dosimetry) measurements in case (a) and GafchromicTM EBT3 film measurements in case (b). During delivery, the target 6 motion patterns available as a standard on CIRSTM motion phantom were investigated: in case (a), the target was moving along the designated sine or cosine4 3D trajectory; in case (b), the inserted marker was moving sinusoidally in 1D. Results: The ion chamber measurements have shown the agreement with the planned dose within 1% under all the studied motion conditions. The film measurements show 98.1% agreement with the planar calculated dose (gamma criteria: 3%/3mm). Conclusion: We successfully verified the capability of the SBRT VeroTM linac to perform real-time tumor tracking and accurate dose delivery to the target, based on predictive modeling of the correlation between implanted marker motion and

  8. Prostate Specific Antigen (PSA as Predicting Marker for Clinical Outcome and Evaluation of Early Toxicity Rate after High-Dose Rate Brachytherapy (HDR-BT in Combination with Additional External Beam Radiation Therapy (EBRT for High Risk Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Thorsten H. Ecke

    2016-11-01

    Full Text Available High-dose-rate brachytherapy (HDR-BT with external beam radiation therapy (EBRT is a common treatment option for locally advanced prostate cancer (PCa. Seventy-nine male patients (median age 71 years, range 50 to 79 with high-risk PCa underwent HDR-BT following EBRT between December 2009 and January 2016 with a median follow-up of 21 months. HDR-BT was administered in two treatment sessions (one week interval with 9 Gy per fraction using a planning system and the Ir192 treatment unit GammaMed Plus iX. EBRT was performed with CT-based 3D-conformal treatment planning with a total dose administration of 50.4 Gy with 1.8 Gy per fraction and five fractions per week. Follow-up for all patients was organized one, three, and five years after radiation therapy to evaluate early and late toxicity side effects, metastases, local recurrence, and prostate-specific antigen (PSA value measured in ng/mL. The evaluated data included age, PSA at time of diagnosis, PSA density, BMI (body mass index, Gleason score, D’Amico risk classification for PCa, digital rectal examination (DRE, PSA value after one/three/five year(s follow-up (FU, time of follow-up, TNM classification, prostate volume, and early toxicity rates. Early toxicity rates were 8.86% for gastrointestinal, and 6.33% for genitourinary side effects. Of all treated patients, 84.81% had no side effects. All reported complications in early toxicity were grade 1. PSA density at time of diagnosis (p = 0.009, PSA on date of first HDR-BT (p = 0.033, and PSA on date of first follow-up after one year (p = 0.025 have statistical significance on a higher risk to get a local recurrence during follow-up. HDR-BT in combination with additional EBRT in the presented design for high-risk PCa results in high biochemical control rates with minimal side-effects. PSA is a negative predictive biomarker for local recurrence during follow-up. A longer follow-up is needed to assess long-term outcome and toxicities.

  9. Regulating multiple externalities

    DEFF Research Database (Denmark)

    Waldo, Staffan; Jensen, Frank; Nielsen, Max

    2016-01-01

    Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory instrume......Open access is a well-known externality problem in fisheries causing excess capacity and overfishing. Due to global warming, externality problems from CO2 emissions have gained increased interest. With two externality problems, a first-best optimum can be achieved by using two regulatory...

  10. Evaluation of fecal recovering and long term bias of internal and external markers in a digestion assay with cattle Recuperação fecal e vício de tempo longo de indicadores internos e externos em ensaio de digestão com bovinos

    Directory of Open Access Journals (Sweden)

    Cláudia Batista Sampaio

    2011-01-01

    Full Text Available The objective of this work was to estimate the total recovering and the long term bias of the estimates of fecal excretion using the external markers chromic oxide and titanium dioxide and internal markers indigestible dry matter (iDM, indigestible neutral detergent fiber (iNDF and indigestible acid detergent fiber (iADF in a digestion assay with cattle fed different diets. Fourteen F1 Red Angus x Nellore averaging 12 months and 287 kg were used. The animals were fed with elephant grass silage, corn silage or signal grass hay and supplemented or not with 20% of concentrate. The experiment consisted of two 13-days experimental periods according to a 2 x 2 Latin square design with seven squares. The animals received 10 g/d of chromic oxide and titanium dioxide through esophageal sounder. There was no effect of forage, concentrate or their interaction on fecal recovering of external and internal markers. The average fecal recovering of chromic oxide and titanium dioxide were 99.50% and 101.95%, respectively. iDM, iNDF and iADF presented average fecal recovering of 99.02%, 98.87% and 102.07%, respectively. For all markers the fecal recovering was found to be 100% and all of them presented no long term bias. However, higher precision was observed for fecal excretion estimates obtained with internal markers.Objetivou-se estimar a recuperação total e o vício de tempo longo das estimativas de excreção fecal obtidas com os indicadores externos óxido crômico e dióxido de titânio e com os indicadores internos matéria seca indigestível (MSi, fibra em detergente neutro indigestível (FDNi e fibra em detergente ácido indigestível (FDAi em ensaio de digestão com bovinos alimentados com diferentes dietas. Foram utilizados 14 novilhos F1 Red Angus x Nelore, não-castrados, com idade e peso médios de 12 meses e 287 kg. Os animais foram alimentados com silagem de capim-elefante, silagem de milho ou feno de capim-braquiária, suplementados ou n

  11. ExternE National Implementation Finland

    Energy Technology Data Exchange (ETDEWEB)

    Pingoud, K.; Maelkki, H.; Wihersaari, M.; Pirilae, P. [VTT Energy, Espoo (Finland); Hongisto, M. [Imatran Voima Oy, Vantaa (Finland); Siitonen, S. [Ekono Energy Ltd, Espoo (Finland); Johansson, M. [Finnish Environment Institute, Helsinki (Finland)

    1999-07-01

    ExternE National Implementation is a continuation of the ExternE Project, funded in part by the European Commission's Joule III Programme. This study is the result of the ExternE National Implementation Project for Finland. Three fuel cycles were selected for the Finnish study: coal, peat and wood-derived biomass, which together are responsible for about 40% of total electricity generation in Finland and about 75% of the non-nuclear fuel based generation. The estimated external costs or damages were dominated by the global warming (GW) impacts in the coal and peat fuel cycles, but knowledge of the true GW impacts is still uncertain. From among other impacts that were valued in monetary terms the human health damages due to airborne emissions dominated in all the three fuel cycles. Monetary valuation for ecosystem impacts is not possible using the ExternE methodology at present. The Meri-Pori power station representing the coal fuel cycle is one of the world's cleanest and most efficient coal-fired power plants with a condensing turbine. The coal is imported mainly from Poland. The estimated health damages were about 4 mECU/kWh, crop damages an order of magnitude lower and damages caused to building materials two orders of magnitude lower. The power stations of the peat and biomass fuel cycles are of CHP type, generating electricity and heat for the district heating systems of two cities. Their fuels are of domestic origin. The estimated health damages allocated to electricity generation were about 5 and 6 mECU/kWh, respectively. The estimates were case-specific and thus an generalisation of the results to the whole electricity generation in Finland is unrealistic. Despite the uncertainties and limitations of the methodology, it is a promising tool in the comparison of similar kinds of fuel cycles, new power plants and pollution abatement technologies and different plant locations with each other. (orig.)

  12. Tracking Porters

    DEFF Research Database (Denmark)

    Bruun, Maja Hojer; Krause-Jensen, Jakob; Saltofte, Margit

    2015-01-01

    Anthropology attempts to gain insight into people's experiential life-worlds through long-term fieldwork. The quality of anthropological knowledge production, however, does not depend solely on the duration of the stay in the field, but also on a particular way of seeing social situations. The an...... the students followed the work of a group of porters. Drawing on anthropological concepts and research strategies the students gained crucial insights about the potential effects of using tracking technologies in the hospital....

  13. A comparative study between the imaging system and the optical tracking system in proton therapy at CNAO

    CERN Document Server

    Desplanques, Maxime; Fontana, Giulia; Pella, Andrea; Riboldi, Marco; Fattori, Giovanni; Donno, Andrea; Baroni, Guido; Orecchia, Roberto

    2013-01-01

    The synergy between in-room imaging and optical tracking, in co-operation with highly accurate robotic patient handling represents a concept for patient-set-up which has been implemented at CNAO (Centro Nazionale di Adroterapia Oncologica). In-room imaging is based on a double oblique X-ray projection system; optical tracking consists of the detection of the position of spherical markers placed directly on the patient’s skin or on the immobilization devices. These markers are used as external fiducials during patient positioning and dose delivery. This study reports the results of a comparative analysis between in-room imaging and optical tracking data for patient positioning within the framework of high-precision particle therapy. Differences between the optical tracking system (OTS) and the imaging system (IS) were on average within the expected localization accuracy. On the first 633 fractions for head and neck (H&N) set-up procedures, the corrections applied by the IS, after patient positioning usin...

  14. ASH External Web Portal (External Portal) -

    Data.gov (United States)

    Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

  15. 6DOF optical tracking system using afocal optics for image guided surgery

    Directory of Open Access Journals (Sweden)

    Chae You Seong

    2015-01-01

    Full Text Available Image guided surgery using medical robots is becoming popular these days. For image guided surgery, a tracking system is required to provide 6DOF information of patient coordinate, surgical instruments and medical robots used in surgery. To provide 6DOF information, a marker has to be attached to the target. However, it is hard to use many markers all together because the markers will take too much space in the surgical area. The tracking system proposed in this study utilizes down sized markers compared to traditional markers by using micro-engraved data-coded pattern with a lens instead of using geometrically specified marker spheres as a tracking target. A tracking system is developed that has a measurement area of 1m to 2.5m from the tracking system. Experiment has been done for surgical navigation using the proposed tracking system and a medical robot.

  16. Occurrence of human-associated Bacteroidetes genetic source tracking markers in raw and treated wastewater of municipal and domestic origin and comparison to standard and alternative indicators of faecal pollution.

    Science.gov (United States)

    Mayer, R E; Bofill-Mas, S; Egle, L; Reischer, G H; Schade, M; Fernandez-Cassi, X; Fuchs, W; Mach, R L; Lindner, G; Kirschner, A; Gaisbauer, M; Piringer, H; Blaschke, A P; Girones, R; Zessner, M; Sommer, R; Farnleitner, A H

    2016-03-01

    This was a detailed investigation of the seasonal occurrence, dynamics, removal and resistance of human-associated genetic Bacteroidetes faecal markers (GeBaM) compared with ISO-based standard faecal indicator bacteria (SFIB), human-specific viral faecal markers and one human-associated Bacteroidetes phage in raw and treated wastewater of municipal and domestic origin. Characteristics of the selected activated sludge wastewater treatment plants (WWTPs) from Austria and Germany were studied in detail (WWTPs, n = 13, connected populations from 3 to 49000 individuals), supported by volume-proportional automated 24-h sampling and chemical water quality analysis. GeBaM were consistently detected in high concentrations in raw (median log10 8.6 marker equivalents (ME) 100 ml(-1)) and biologically treated wastewater samples (median log10 6.2-6.5 ME 100 ml(-1)), irrespective of plant size, type and time of the season (n = 53-65). GeBaM, Escherichia coli, and enterococci concentrations revealed the same range of statistical variability for raw (multiplicative standard deviations s* = 2.3-3.0) and treated wastewater (s* = 3.7-4.5), with increased variability after treatment. Clostridium perfringens spores revealed the lowest variability for raw wastewater (s* = 1.5). In raw wastewater correlations among microbiological parameters were only detectable between GeBaM, C. perfringens and JC polyomaviruses. Statistical associations amongst microbial parameters increased during wastewater treatment. Two plants with advanced treatment were also investigated, revealing a minimum log10 5.0 (10th percentile) reduction of GeBaM in the activated sludge membrane bioreactor, but no reduction of the genetic markers during UV irradiation (254 nm). This study highlights the potential of human-associated GeBaM to complement wastewater impact monitoring based on the determination of SFIB. In addition, human-specific JC polyomaviruses and adenoviruses seem to be a valuable support

  17. A novel strong tracking finite-difference extended Kalman filter for nonlinear eye tracking

    Institute of Scientific and Technical Information of China (English)

    ZHANG ZuTao; ZHANG JiaShu

    2009-01-01

    Non-Intrusive methods for eye tracking are Important for many applications of vision-based human computer interaction. However, due to the high nonlinearity of eye motion, how to ensure the robust-ness of external interference and accuracy of eye tracking poses the primary obstacle to the integration of eye movements into today's interfaces. In this paper, we present a strong tracking finite-difference extended Kalman filter algorithm, aiming to overcome the difficulty In modeling nonlinear eye tracking. In filtering calculation, strong tracking factor is introduced to modify a priori covariance matrix and im-prove the accuracy of the filter. The filter uses finite-difference method to calculate partial derivatives of nonlinear functions for eye tracking. The latest experimental results show the validity of our method for eye tracking under realistic conditions.

  18. Eye-Hand Synergy and Intermittent Behaviors during Target-Directed Tracking with Visual and Non-visual Information

    OpenAIRE

    2012-01-01

    Visual feedback and non-visual information play different roles in tracking of an external target. This study explored the respective roles of the visual and non-visual information in eleven healthy volunteers who coupled the manual cursor to a rhythmically moving target of 0.5 Hz under three sensorimotor conditions: eye-alone tracking (EA), eye-hand tracking with visual feedback of manual outputs (EH tracking), and the same tracking without such feedback (EHM tracking). Tracking error, kinem...

  19. Tracking telecommuting

    Energy Technology Data Exchange (ETDEWEB)

    Stastny, P.

    2007-03-15

    Many employees are now choosing to work from home using laptops and telephones. Employers in the oil and gas industry are now reaping a number of benefits from their telecommuting employees, including increased productivity; higher levels of employee satisfaction, and less absenteeism. Providing a telecommunication option can prove to be advantageous for employers wishing to hire or retain employees. Telecommuting may also help to reduce greenhouse gas (GHG) emissions. This article provided details of Teletrips Inc., a company that aids in the production of corporate social responsibility reports. Teletrips provides reports that document employee savings in time, vehicle depreciation maintenance, and gasoline costs. Teletrips currently tracks 12 companies in Calgary, and plans to grow through the development of key technology partnerships. The company is also working with the federal government to provide their clients with emission trading credits, and has forged a memorandum of understanding with the British Columbia government for tracking emissions. Calgary now openly supports telecommuting and is encouraging businesses in the city to adopt telecommuting on a larger scale. It was concluded that the expanding needs for road infrastructure and the energy used by cars to move workers in and out of the city are a massive burden to the city's tax base. 1 fig.

  20. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The Objective for 2006 was to complete all of the CMS Tracker sub-detectors and to start the integration of the sub-detectors into the Tracker Support Tube (TST). The Objective for 2007 is to deliver to CMS a completed, installed, commissioned and calibrated Tracking System (Silicon Strip and Pixels) aligned to < 100µ in April 2008 ready for the first physics collisions at LHC. In November 2006 all of the sub-detectors had been delivered to the Tracker Integration facility (TIF) at CERN and the tests and QA procedures to be carried out on each sub-detector before integration had been established. In December 2006, TIB/TID+ was integrated into TOB+, TIB/TID- was being prepared for integration, and TEC+ was undergoing tests at the final tracker operating temperature (-100 C) in the Lyon cold room. In February 2007, TIB/TID- has been integrated into TOB-, and the installation of the pixel support tube and the services for TI...

  1. Botnet Tracking

    OpenAIRE

    Esteban Gutierrez, Alvaro

    2015-01-01

    Una Botnet és una xarxa d'ordinadors anomenats Bots, controlats sense autorització del propietari i de forma remota per un agent extern maliciós anomenat Command & Control. Aquestes xarxes son conegudes principalment pels seus atacs de denegació de servei distribuït (DDoS) essent aquesta la motivació per trobar nous mecanismes de detecció d'aquestes xarxes i així ser capaç de minimitzar l'impacte d'un atac. Una Botnet és una xarxa d'ordinadors anomenats Bots, controlats sense autorització del...

  2. External radiation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  3. Computer program TRACK_VISION for simulating optical appearance of etched tracks in CR-39 nuclear track detectors

    Science.gov (United States)

    Nikezic, D.; Yu, K. N.

    2008-04-01

    A computer program called TRACK_VISION for determining the optical appearances of tracks in nuclear track materials resulted from light-ion irradiation and subsequent chemical etching was described. A previously published software, TRACK_TEST, was the starting point for the present software TRACK_VISION, which contained TRACK_TEST as its subset. The programming steps were outlined. Descriptions of the program were given, including the built-in V functions for the commonly employed nuclear track material commercially known as CR-39 (polyallyldiglycol carbonate) irradiated by alpha particles. Program summaryProgram title: TRACK_VISION Catalogue identifier: AEAF_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAF_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 4084 No. of bytes in distributed program, including test data, etc.: 71 117 Distribution format: tar.gz Programming language: Fortran 90 Computer: Pentium PC Operating system: Windows 95+ RAM: 256 MB Classification: 17.5, 18 External routines: The entire code must be linked with the MSFLIB library. MSFLib is a collection of C and C++ modules which provides a general framework for processing IBM's AFP datastream. MSFLIB is specific to Visual Fortran (Digital, Compaq or Intel flavors). Nature of problem: Nuclear track detectors are commonly used for radon measurements through studying the tracks generated by the incident alpha particles. Optical microscopes are often used for this purpose but the process is relatively tedious and time consuming. Several automatic and semi-automatic systems have been developed in order to facilitate determination of track densities. In all these automatic systems, the optical appearance of the tracks is important. However, not much has been done so far to obtaining the

  4. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The successful commissioning of ~ 25% of the Silicon Strip Tracker was completed in the Tracker Integration Facility (TIF) at CERN in July 2007 and the Tracker has since been prepared for moving and installation into CMS at P5. The Tracker was ready to move on schedule in September 2007. The Installation of the Tracker cooling pipes and LV cables between Patch Panel 1 (PP1) on the inside the CMS magnet cryostat, and the cooling plants and power system racks on the balconies has been completed. The optical fibres from PP1 to the readout FEDs in the USC have been installed, together with the Tracker cable channels, in parallel with the installation of the EB/HB services. All of the Tracker Safety, Power, DCS and the VME Readout Systems have been installed at P5 and are being tested and commissioned with CMS. It is planned to install the Tracker into CMS before Christmas. The Tracker will then be connected to the pre-installed services on Y...

  5. INNER TRACKING

    CERN Multimedia

    P. Sharp

    The CMS Inner Tracking Detector continues to make good progress. The successful commissioning of ~ 25% of the Silicon Strip Tracker was completed in the Tracker Integration Facility (TIF) at CERN on 18 July 2007 and the Tracker has since been prepared for moving and installation into CMS at P5. The Tracker will be ready to move on schedule in September 2007. The Installation of the Tracker cooling pipes and LV cables between Patch Panel 1 (PP1) on the inside the CMS magnet cryostat, and the cooling plants and power system racks on the balconies has been completed. The optical fibres from PP1 to the readout FEDs in the USC will be installed in parallel with the installation of the EB/HB services, and will be completed in October. It is planned to install the Tracker into CMS at the end of October, after the completion of the installation of the EB/HB services. The Tracker will then be connected to the pre-installed services on YB0 and commissioned with CMS in December. The FPix and BPix continue to make ...

  6. Patient Treatment Tracking Chart

    Science.gov (United States)

    ... ZIP code here Hepatitis C Treatment Tracking Chart Patient Treatment Tracking Chart Patient Treatment Tracking Chart Sample Chart This chart is ... this website Submit Share this page Related Resource Patient Treatment Tutorial return to top CONNECT Veterans Crisis ...

  7. Track and Cut: Simultaneous Tracking and Segmentation of Multiple Objects with Graph Cuts

    Directory of Open Access Journals (Sweden)

    Patrick Pérez

    2008-06-01

    Full Text Available This paper presents a new method to both track and segment multiple objects in videos using min-cut/max-flow optimizations. We introduce objective functions that combine low-level pixel wise measures (color, motion, high-level observations obtained via an independent detection module, motion prediction, and contrast-sensitive contextual regularization. One novelty is that external observations are used without adding any association step. The observations are image regions (pixel sets that can be provided by any kind of detector. The minimization of appropriate cost functions simultaneously allows “detection-before-track” tracking (track-to-observation assignment and automatic initialization of new tracks and segmentation of tracked objects. When several tracked objects get mixed up by the detection module (e.g., a single foreground detection mask is obtained for several objects close to each other, a second stage of minimization allows the proper tracking and segmentation of these individual entities despite the confusion of the external detection module.

  8. Fast particle tracking with wake fields

    Energy Technology Data Exchange (ETDEWEB)

    Dohlus, M.; Floettmann, K.; Henning, C.

    2012-01-15

    Tracking calculations of charged particles in electromagnetic fields require in principle the simultaneous solution of the equation of motion and of Maxwell's equations. In many tracking codes a simpler and more efficient approach is used: external fields like that of the accelerating structures are provided as field maps, generated in separate computations and for the calculation of self fields the model of a particle bunch in uniform motion is used. We describe how an externally computed wake function can be approximated by a table of Taylor coefficients and how the wake field kick can be calculated for the particle distribution in a tracking calculation. The integrated kick, representing the effect of a distributed structure, is applied at a discrete time. As an example, we use our approach to calculate the emittance growth of a bunch in an undulator beam pipe due to resistive wall wake field effects. (orig.)

  9. Estimating missing marker positions using low dimensional Kalman smoothing.

    Science.gov (United States)

    Burke, M; Lasenby, J

    2016-06-14

    Motion capture is frequently used for studies in biomechanics, and has proved particularly useful in understanding human motion. Unfortunately, motion capture approaches often fail when markers are occluded or missing and a mechanism by which the position of missing markers can be estimated is highly desirable. Of particular interest is the problem of estimating missing marker positions when no prior knowledge of marker placement is known. Existing approaches to marker completion in this scenario can be broadly divided into tracking approaches using dynamical modelling, and low rank matrix completion. This paper shows that these approaches can be combined to provide a marker completion algorithm that not only outperforms its respective components, but also solves the problem of incremental position error typically associated with tracking approaches.

  10. On the development of inexpensive speed and position tracking system for swimming

    DEFF Research Database (Denmark)

    Trangbæk, Søren; Rasmussen, Cuno; Andersen, Thomas Bull

    2016-01-01

    A semi-automated tracking system was developed for the analysis of swimming, using cameras, an LED diode marker, and a red swim cap. Four experienced young swimmers were equipped with a marker and a swim cap and their position and speed was tracked throughout above-water and under-water swimming...

  11. Stabilization of unstable pelvic fractures with a novel internal-external fixator

    Institute of Scientific and Technical Information of China (English)

    JIANG Zan-li; Gary Chen

    2011-01-01

    An internal-external fixator for stabilization in three cases with unstable pelvic fractures were reported.Compared with external fixation,the internal-external fixator,which is placed in the subcutaneous layer,decreased the risk of pin-track infection,pin site pain,and bowel obstruction; meanwhile,it had the advantage of external fixation:it was easy to apply,controlled damage,and resulted in minimal injury.

  12. Externally Verifiable Oblivious RAM

    Directory of Open Access Journals (Sweden)

    Gancher Joshua

    2017-04-01

    Full Text Available We present the idea of externally verifiable oblivious RAM (ORAM. Our goal is to allow a client and server carrying out an ORAM protocol to have disputes adjudicated by a third party, allowing for the enforcement of penalties against an unreliable or malicious server. We give a security definition that guarantees protection not only against a malicious server but also against a client making false accusations. We then give modifications of the Path ORAM [15] and Ring ORAM [9] protocols that meet this security definition. These protocols both have the same asymptotic runtimes as the semi-honest original versions and require the external verifier to be involved only when the client or server deviates from the protocol. Finally, we implement externally verified ORAM, along with an automated cryptocurrency contract to use as the external verifier.

  13. External Beam Therapy (EBT)

    Science.gov (United States)

    ... Esophageal Cancer Treatment Head and Neck Cancer Treatment Lung Cancer Treatment Prostate Cancer Treatment Brain Tumor Treatment Why is ... Radiation Oncology) Breast Cancer Treatment Esophageal Cancer Treatment Lung Cancer Treatment Images related to External Beam Therapy (EBT) Sponsored ...

  14. MALIGNANT EXTERNAL OTITIS

    OpenAIRE

    Massoud Moghaddam

    1993-01-01

    Two case reports of malignant external otitis in the elderly diabetics and their complications and management with regard to our experience at Amir Alam Hospital, Department of ENT will be discussed here.

  15. Checklists for external validity

    DEFF Research Database (Denmark)

    Dyrvig, Anne-Kirstine; Kidholm, Kristian; Gerke, Oke;

    2014-01-01

    RATIONALE, AIMS AND OBJECTIVES: The quality of the current literature on external validity varies considerably. An improved checklist with validated items on external validity would aid decision-makers in judging similarities among circumstances when transferring evidence from a study setting...... to an implementation setting. In this paper, currently available checklists on external validity are identified, assessed and used as a basis for proposing a new improved instrument. METHOD: A systematic literature review was carried out in Pubmed, Embase and Cinahl on English-language papers without time restrictions....... The retrieved checklist items were assessed for (i) the methodology used in primary literature, justifying inclusion of each item; and (ii) the number of times each item appeared in checklists. RESULTS: Fifteen papers were identified, presenting a total of 21 checklists for external validity, yielding a total...

  16. Migration with fiscal externalities.

    Science.gov (United States)

    Hercowitz, Z; Pines, D

    1991-11-01

    "This paper analyses the distribution of a country's population among regions when migration involves fiscal externalities. The main question addressed is whether a decentralized decision making [by] regional governments can produce an optimal population distribution...or a centralized intervention is indispensable, as argued before in the literature.... It turns out that, while with costless mobility the fiscal externality is fully internalized by voluntary interregional transfers, with costly mobility, centrally coordinated transfers still remain indispensable for achieving the socially optimal allocation."

  17. Sen cycles and externalities

    OpenAIRE

    Piggins, Ashley; Salerno, Gillian

    2016-01-01

    It has long been understood that externalities of some kind are responsible for Sen’s (1970) theorem on the impossibility of a Paretian liberal. However, Saari and Petron (2006) show that for any social preference cycle generated by combining the weak Pareto principle and individual decisiveness, every decisive individual must suffer at least one strong negative externality. We show that this fundamental result only holds when individual preferences are strict. Building on their contribution,...

  18. High Precision Control of Ship-Mounted Satellite Tracking Antenna

    DEFF Research Database (Denmark)

    Mohsen, Soltani; Izadi-Zamanabadi, Roozbeh; Wisniewski, Rafal

    2007-01-01

    The telecommunication on a modern merchandise ship is maintained by means of satellite communication. The task of the tracking system is to position the on-board antenna toward a chosen satellite. The control system is capable of rejecting the external disturbances which affect on the under......-actuated antenna and ensures that it remains locked on the satellite. In this paper, a nonlinear internal model controller (NIMC), which achieves asymptotic tracking for the nonlinear antenna system with nonlinear exogenous dynamics, is proposed. Computer simulations as well as practical tests verify...... the effectiveness of this method to cope with the external disturbances that are imposed to the satellite tracking antenna (STA)....

  19. High Precision Control of Ship-Mounted Satellite Tracking Antenna

    DEFF Research Database (Denmark)

    Mohsen, Soltani; Izadi-Zamanabadi, Roozbeh; Wisniewski, Rafal

    2007-01-01

    The telecommunication on a modern merchandise ship is maintained by means of satellite communication. The task of the tracking system is to position the on-board antenna toward a chosen satellite. The control system is capable of rejecting the external disturbances which affect on the under......-actuated antenna and ensures that it remains locked on the satellite. In this paper, a nonlinear internal model controller (NIMC), which achieves asymptotic tracking for the nonlinear antenna system with nonlinear exogenous dynamics, is proposed. Computer simulations as well as practical tests verify...... the effectiveness of this method to cope with the external disturbances that are imposed to the satellite tracking antenna (STA)....

  20. Solar tracking system

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  1. Disturbance observer based position tracking of electro-hydraulic actuator

    Institute of Scientific and Technical Information of China (English)

    国凯; 魏建华; 田启岩

    2015-01-01

    A nonlinear controller based on an extended second-order disturbance observer is presented to track desired position for an electro-hydraulic single-rod actuator in the presence of both external disturbances and parameter uncertainties. The proposed extended second-order disturbance observer deals with not only the external perturbations, but also parameter uncertainties which are commonly regarded as lumped disturbances in previous researches. Besides, the outer position tracking loop is designed with cylinder load pressure as output; and the inner pressure control loop provides the hydraulic actuator the characteristic of a force generator. The stability of the closed-loop system is provided based on Lyapunov theory. The performance of the controller is verified through simulations and experiments. The results demonstrate that the proposed nonlinear position tracking controller, together with the extended second-order disturbance observer, gives an excellent tracking performance in the presence of parameter uncertainties and external disturbance.

  2. TPC track distortions III: fiat lux

    CERN Document Server

    Boyko, I; Dydak, F; Elagin, A; Gostkin, M; Guskov, A; Koreshev, V; Nefedov, Y; Nikolaev, K; Veenhof, R; Wotschack, J; Zhemchugov, A

    2005-01-01

    We present a comprehensive overview and final summary of all four types of static track distortions seen in the HARP TPC, in terms of physical origins, mathematical modelling, and correction algorithms. 'Static'™ distortions are defined as not depending on the event time within the 400 ms long accelerator spill. Calculated static distortions are compared with measurements from cosmic-muon tracks. We characterize track distortions by the r phi residuals of cluster positions with respect to the transverse projection of a helical trajectory constrained by hits in the RPC overlap regions. This method provides a fixed TPC-external reference system (by contrast to the co-moving coordinate system associated with a fit) which solely permits to identify individually, and measure quantitatively, the static TPC track distortions arising from (i) the inhomogeneity of the solenoidal magnetic field, (ii) the inhomogeneity of the electric field from the high-voltage mismatch between the inner and outer TPC field cages, (...

  3. Evolution of the Tracking Code PLACET

    CERN Document Server

    Latina, A; Schulte, D; Snuverink, J

    2013-01-01

    The tracking code PLACET simulates beam transport and orbit corrections in linear accelerators. It incorporates single- and multi-bunch effects, static and dynamic imperfections. A major restructuring of its core has resulted in an improvement in its modularity, with some immediate advantages: its tracking core, which is one of the fastest available for this kind of simulations, is now interfaced toward three different scripting languages to further expand its simulation capabilities: Tcl/Tk, Octave, and Python. These three languages provide access to a vast and diverse library of scientific tools, mechanisms for parallel computing, and access to Java interfaces for control systems. Also, several new functionalities have been added to the PLACET core itself: parallel tracking to exploit modern multicore CPUs and clusters of computers, the possibility to track through the interaction region in presence of external magnetic fields (detector solenoid) and higher order imperfections in magnets. PLACET is currentl...

  4. Environmental external effects from wind power based on the EU ExternE methodology

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1998-01-01

    The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective...

  5. Externality or sustainability economics?

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, Jeroen C.J.M. van den [ICREA, Barcelona (Spain); Department of Economics and Economic History and Institute for Environmental Science and Technology, Universitat Autonoma de Barcelona (Spain)

    2010-09-15

    In an effort to develop 'sustainability economics' Baumgaertner and Quaas (2010) neglect the central concept of environmental economics-'environmental externality'. This note proposes a possible connection between the concepts of environmental externality and sustainability. In addition, attention is asked for other aspects of 'sustainability economics', namely the distinction weak/strong sustainability, spatial sustainability and sustainable trade, distinctive sustainability policy, and the ideas of early 'sustainability economists'. I argue that both sustainability and externalities reflect a systems perspective and propose that effective sustainability solutions require that more attention is given to system feedbacks, notably other-regarding preferences and social interactions, and energy and environmental rebound. The case of climate change and policy is used to illustrate particular statements. As a conclusion, a list of 20 insights and suggestions for research is offered. (author)

  6. Metasurface external cavity laser

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Luyao, E-mail: luyaoxu.ee@ucla.edu; Curwen, Christopher A.; Williams, Benjamin S. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); California NanoSystems Institute, University of California, Los Angeles, California 90095 (United States); Hon, Philip W. C.; Itoh, Tatsuo [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Chen, Qi-Sheng [Northrop Grumman Aerospace Systems, Redondo Beach, California 90278 (United States)

    2015-11-30

    A vertical-external-cavity surface-emitting-laser is demonstrated in the terahertz range, which is based upon an amplifying metasurface reflector composed of a sub-wavelength array of antenna-coupled quantum-cascade sub-cavities. Lasing is possible when the metasurface reflector is placed into a low-loss external cavity such that the external cavity—not the sub-cavities—determines the beam properties. A near-Gaussian beam of 4.3° × 5.1° divergence is observed and an output power level >5 mW is achieved. The polarized response of the metasurface allows the use of a wire-grid polarizer as an output coupler that is continuously tunable.

  7. 基于不安全性、健康影响和机动化交通外部成本的步行和自行车道网络的成本效益分析%Cost-benefit Analyses of Walking and Cycling Track Networks Taking into Account Insecurity,Health Effects and External Costs of Motorized Traffic

    Institute of Scientific and Technical Information of China (English)

    卡加汤·赛伦斯敏德; 邹晖

    2012-01-01

    The study presents cost-benefit analyses of walking and cycling track networks in three Norwegian cities. The cost-benefit analyses take into account the benefit of reduced insecurity and the health benefits of the improved fitness the use of non-motorized transport provides. In addition to reductions in health costs, the analyses also take into account that a change from travel by car to cycling or walking means reduced external costs (e.g. air pollution and noise) from motorized traffic and reduced parking costs. The benefits of investments in cycle networks are estimated to be at least 4~5 times the costs. Such investments are thus more beneficial to society than other transport investments. The results of such complete cost-benefit analyses make it possible to calculate the benefits to society that are not realized because motorized traffic prevents people from bicycling or walking as much as they otherwise would prefer. These ' barrier costs' attributable to motorized traffic are estimated to be of at least the same magnitude as air pollution costs and more than double the noise costs. Barrier costs should therefore be taken into account in the same way as other external costs, when the issue is to determine the proper level of car taxes or to evaluate different kinds of restrictions on car use.%本文介绍了对三个挪威城市中步行和自行车道网络进行的成本效益分析.这项成本效益分析考虑了由采用非机动化交通方式带来的不安全性的减少和健康收益.除了健康成本的降低之外,分析还考虑了从开车出行转变为骑自行车出行或步行带来的机动化交通外部成本的减少(如空气污染和噪音)以及停车成本的降低.投资自行车道网络带来的收益估计至少是其成本的4~5倍.因此这种投资比其他交通投资对社会更有益.此项完整的成本效益分析的结果使人们有可能计算原来没有被意识到的社会效益——因为机动化交通阻

  8. Methods for abdominal respiratory motion tracking.

    Science.gov (United States)

    Spinczyk, Dominik; Karwan, Adam; Copik, Marcin

    2014-01-01

    Non-invasive surface registration methods have been developed to register and track breathing motions in a patient's abdomen and thorax. We evaluated several different registration methods, including marker tracking using a stereo camera, chessboard image projection, and abdominal point clouds. Our point cloud approach was based on a time-of-flight (ToF) sensor that tracked the abdominal surface. We tested different respiratory phases using additional markers as landmarks for the extension of the non-rigid Iterative Closest Point (ICP) algorithm to improve the matching of irregular meshes. Four variants for retrieving the correspondence data were implemented and compared. Our evaluation involved 9 healthy individuals (3 females and 6 males) with point clouds captured in opposite breathing phases (i.e., inhalation and exhalation). We measured three factors: surface distance, correspondence distance, and marker error. To evaluate different methods for computing the correspondence measurements, we defined the number of correspondences for every target point and the average correspondence assignment error of the points nearest the markers.

  9. Weld pool visual sensing without external illumination

    DEFF Research Database (Denmark)

    Liu, Jinchao; Fan, Zhun; Olsen, Soren Ingvor

    2011-01-01

    Visual sensing in arc welding has become more and more important, but still remains challenging because of the harsh environment with extremely strong illumination from the arc. This paper presents a low-cost camera-based sensor system, without using external Illumination, but nevertheless able...... to sense and model the weld pool. Central is a carefully selected optical filtering as well as an active contour-based tracking of the weld pool boundary. The system is able to extract the 2D shape of the weld pool in real time. The reported experiments show the feasibility of this approach....

  10. Enlargement of the External Mobility Programme

    CERN Multimedia

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has attracted considerable interest from both CERN personnel as well as from several major European companies. The CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CE...

  11. Enlargement of the External Mobility Programme

    CERN Document Server

    HR Department

    2008-01-01

    The External Mobility Programme was launched at the end of September 2007. Initially, the programme was aimed at staff members on limited-duration contracts, having received formal notification of the termination of their employment contract at CERN, to help them towards their next employment. The programme provides a privileged, fast-track entry into the recruitment process of partner companies. Despite the short time since its inception, the programme has already delivered some encouraging and concrete results in terms of interviews granted to participating staff. The Programme has raised considerable interest from both CERN personnel as well as from several major European companies. CERN Management has decided to broaden the scope of the External Mobility Programme. The Programme is now open to: All staff members whose limited duration contract will end in less than one year, as well as all those with indefinite contracts. All fellows who have been employed by CERN fo...

  12. Tracking Hypoxic Signaling in Encapsulated Stem Cells

    Science.gov (United States)

    Sahai, Suchit; McFarland, Rachel; Skiles, Mathew L.; Sullivan, Denise; Williams, Amanda

    2012-01-01

    Oxygen is not only a nutrient but also an important signaling molecule whose concentration can influence the fate of stem cells. This study details the development of a marker of hypoxic signaling for use with encapsulated cells. Testing of the marker was performed with adipose-derived stem cells (ADSCs) in two-dimensional (2D) and 3D culture conditions in varied oxygen environments. The cells were genetically modified with our hypoxia marker, which produces a red fluorescent protein (DsRed-DR), under the control of a hypoxia-responsive element (HRE) trimer. For 3D culture, ADSCs were encapsulated in poly(ethylene glycol)–based hydrogels. The hypoxia marker (termed HRE DsRed-DR) is built on a recombinant adenovirus and ADSCs infected with the marker will display red fluorescence when hypoxic signaling is active. This marker was not designed to measure local oxygen concentration but rather to show how a cell perceives its local oxygen concentration. ADSCs cultured in both 2D and 3D were exposed to 20% or 1% oxygen environments for 96 h. In 2D at 20% O2, the marker signal was not observed during the study period. In 1% O2, the fluorescent signal was first observed at 24 h, with maximum prevalence observed at 96 h as 59%±3% cells expressed the marker. In 3D, the signal was observed in both 1% and 20% O2. The onset of signal in 1% O2 was observed at 4 h, reaching maximum prevalence at 96 h with 76%±4% cells expressing the marker. Interestingly, hypoxic signal was also observed in 20% O2, with 13%±3% cells showing positive marker signal after 96 h. The transcription factor subunit hypoxia inducible factor-1α was tracked in these cells over the same time period by immunostaining and western blot analysis. Immunostaining results in 2D correlated well with our marker at 72 h and 96 h, but 3D results did not correlate well. The western blotting results in 2D and 3D correlated well with the fluorescent marker. The HRE DsRed-DR virus can be used to track

  13. Eye-tracking dysfunctions in schizophrenic patients and their relatives

    Energy Technology Data Exchange (ETDEWEB)

    Holzman, P.S.; Proctor, L.R.; Levy, D.L.; Yasillo, N.J.; Meltzer, H.Y.; Hurt, S.W.

    1974-08-01

    A simple test of smooth-pursuit eye movements disclosed a striking association between deviant eye tracking and clinically diagnosed schizophrenia. A high proportion of the schizophrenic patients' first-degree relatives who were not themselves clinically schizophrenic also showed deviant eye-tracking behavior. The relationship of poor eye tracking and schizophrenia is even stronger when specific psychological test evidence of thought disorder is used operationally to classify patients. The eye-tracking dysfunction may thus represent a genetic marker that can prove highly useful for studying the transmission of a vulnerability to schizophrenia. The findings suggest proprioceptive and interoceptive involvement in schizophrenic pathology. (auth)

  14. Motion tracking for medical imaging: a nonvisible structured light tracking approach.

    Science.gov (United States)

    Olesen, Oline Vinter; Paulsen, Rasmus R; Højgaard, Liselotte; Roed, Bjarne; Larsen, Rasmus

    2012-01-01

    We present a system for head motion tracking in 3D brain imaging. The system is based on facial surface reconstruction and tracking using a structured light (SL) scanning principle. The system is designed to fit into narrow 3D medical scanner geometries limiting the field of view. It is tested in a clinical setting on the high resolution research tomograph (HRRT), Siemens PET scanner with a head phantom and volunteers. The SL system is compared to a commercial optical tracking system, the Polaris Vicra system, from NDI based on translatory and rotary ground truth motions of the head phantom. The accuracy of the systems was similar, with root mean square (rms) errors of 0.09 degrees for ±20 degrees axial rotations, and rms errors of 0.24 mm for ± 25 mm translations. Tests were made using (1) a light emitting diode (LED) based miniaturized video projector, the Pico projector from Texas Instruments, and (2) a customized version of this projector replacing a visible light LED with a 850 nm near infrared LED. The latter system does not provide additional discomfort by visible light projection into the patient's eyes. The main advantage over existing head motion tracking devices, including the Polaris Vicra system, is that it is not necessary to place markers on the patient. This provides a simpler workflow and eliminates uncertainties related to marker attachment and stability. We show proof of concept of a marker less tracking system especially designed for clinical use with promising results.

  15. External motion tracking for brain imaging: structured light tracking with invisible light

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Paulsen, Rasmus Reinhold; Højgaard, Liselotte;

    2010-01-01

    The importance of motion correction in 3D medical imaging increases with increasing scanner resolution. It is necessary for scanners with long image acquisition and low contrast images to correct for patient motion in order to optimize image quality. We present a near infrared structured light st...

  16. Stochastic Control - External Models

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    2005-01-01

    This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...

  17. Productivity Change and Externalities

    DEFF Research Database (Denmark)

    Kravtsova, Victoria

    2014-01-01

    firms and the economy as a whole. The approach used in the current research accounts for different internal as well as external factors that individual firms face and evaluates the effect on changes in productivity, technology as well as the efficiency of domestic firms. The empirical analysis focuses...... change in different types of firms and sectors of the economy...

  18. Multiple external root resorption.

    Science.gov (United States)

    Yusof, W Z; Ghazali, M N

    1989-04-01

    Presented is an unusual case of multiple external root resorption. Although the cause of this resorption was not determined, several possibilities are presented. Trauma from occlusion, periodontal and pulpal inflammation, and resorption of idiopathic origin are all discussed as possible causes.

  19. Orthographic and Phonological Contributions to Reading Development: Tracking Developmental Trajectories Using Masked Priming

    Science.gov (United States)

    Ziegler, Johannes C.; Bertrand, Daisy; Lété, Bernard; Grainger, Jonathan

    2014-01-01

    The present study used a variant of masked priming to track the development of 2 marker effects of orthographic and phonological processing from Grade 1 through Grade 5 in a cross-sectional study. Pseudohomophone (PsH) priming served as a marker for phonological processing, whereas transposed-letter (TL) priming was a marker for coarse-grained…

  20. Orthographic and Phonological Contributions to Reading Development: Tracking Developmental Trajectories Using Masked Priming

    Science.gov (United States)

    Ziegler, Johannes C.; Bertrand, Daisy; Lété, Bernard; Grainger, Jonathan

    2014-01-01

    The present study used a variant of masked priming to track the development of 2 marker effects of orthographic and phonological processing from Grade 1 through Grade 5 in a cross-sectional study. Pseudohomophone (PsH) priming served as a marker for phonological processing, whereas transposed-letter (TL) priming was a marker for coarse-grained…

  1. External conference: Geneva University

    CERN Multimedia

    2006-01-01

    Ecole de physique Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 GENEVE 4 Tél: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 13 December 2006 PARTICLE PHYSICS SEMINAR at 17.00 hrs - Stückelberg Auditorium Radiation Tolerant Sensors for Solid State Tracking Detectors by Dr Michael MOLL / CERN The envisaged upgrade of the Large Hadron Collider (LHC) at CERN towards the Super-LHC (SLHC) with a 10 times increased luminosity of 1035 cm2 s-1 will present severe challenges for the tracking detectors of the SLHC experiments. Unprecedented high radiation levels and track densities and a reduced bunch crossing time in the order of 10 ns as well as the need for cost effective detectors have called for an intensive R&D program. The CERN RD50 collaboration 'Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders' is working on the development of semiconductor sensors matching the requirements of the SLHC. Sensors based on defect engineered silic...

  2. Renewable Energy Tracking Systems

    Science.gov (United States)

    Renewable energy generation ownership can be accounted through tracking systems. Tracking systems are highly automated, contain specific information about each MWh, and are accessible over the internet to market participants.

  3. Forward tracking detectors

    Indian Academy of Sciences (India)

    Klaus Mönig

    2007-11-01

    Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  4. Performance of ATLAS tracking

    CERN Document Server

    Roe, Shaun; The ATLAS collaboration

    2017-01-01

    Run-2 of the Large Hadron Collider (LHC) has provided new challenges to track and vertex reconstruction with higher centre-of-mass energies and luminosity leading to increasingly high-multiplicity envi-ronments. This talk provides an overview of the tracking performance, highlighting tracking improvements due to the Insertable B-Layer (IBL) and the introduction of time-dependent alignment.

  5. Eye-hand synergy and intermittent behaviors during target-directed tracking with visual and non-visual information.

    Science.gov (United States)

    Huang, Chien-Ting; Hwang, Ing-Shiou

    2012-01-01

    Visual feedback and non-visual information play different roles in tracking of an external target. This study explored the respective roles of the visual and non-visual information in eleven healthy volunteers who coupled the manual cursor to a rhythmically moving target of 0.5 Hz under three sensorimotor conditions: eye-alone tracking (EA), eye-hand tracking with visual feedback of manual outputs (EH tracking), and the same tracking without such feedback (EHM tracking). Tracking error, kinematic variables, and movement intermittency (saccade and speed pulse) were contrasted among tracking conditions. The results showed that EHM tracking exhibited larger pursuit gain, less tracking error, and less movement intermittency for the ocular plant than EA tracking. With the vision of manual cursor, EH tracking achieved superior tracking congruency of the ocular and manual effectors with smaller movement intermittency than EHM tracking, except that the rate precision of manual action was similar for both types of tracking. The present study demonstrated that visibility of manual consequences altered mutual relationships between movement intermittency and tracking error. The speed pulse metrics of manual output were linked to ocular tracking error, and saccade events were time-locked to the positional error of manual tracking during EH tracking. In conclusion, peripheral non-visual information is critical to smooth pursuit characteristics and rate control of rhythmic manual tracking. Visual information adds to eye-hand synchrony, underlying improved amplitude control and elaborate error interpretation during oculo-manual tracking.

  6. Eye-Hand Synergy and Intermittent Behaviors during Target-Directed Tracking with Visual and Non-visual Information

    Science.gov (United States)

    Huang, Chien-Ting; Hwang, Ing-Shiou

    2012-01-01

    Visual feedback and non-visual information play different roles in tracking of an external target. This study explored the respective roles of the visual and non-visual information in eleven healthy volunteers who coupled the manual cursor to a rhythmically moving target of 0.5 Hz under three sensorimotor conditions: eye-alone tracking (EA), eye-hand tracking with visual feedback of manual outputs (EH tracking), and the same tracking without such feedback (EHM tracking). Tracking error, kinematic variables, and movement intermittency (saccade and speed pulse) were contrasted among tracking conditions. The results showed that EHM tracking exhibited larger pursuit gain, less tracking error, and less movement intermittency for the ocular plant than EA tracking. With the vision of manual cursor, EH tracking achieved superior tracking congruency of the ocular and manual effectors with smaller movement intermittency than EHM tracking, except that the rate precision of manual action was similar for both types of tracking. The present study demonstrated that visibility of manual consequences altered mutual relationships between movement intermittency and tracking error. The speed pulse metrics of manual output were linked to ocular tracking error, and saccade events were time-locked to the positional error of manual tracking during EH tracking. In conclusion, peripheral non-visual information is critical to smooth pursuit characteristics and rate control of rhythmic manual tracking. Visual information adds to eye-hand synchrony, underlying improved amplitude control and elaborate error interpretation during oculo-manual tracking. PMID:23236498

  7. Poly (dopamine) coated superparamagnetic iron oxide nanocluster for noninvasive labeling, tracking, and targeted delivery of adipose tissue-derived stem cells

    Science.gov (United States)

    Liao, Naishun; Wu, Ming; Pan, Fan; Lin, Jiumao; Li, Zuanfang; Zhang, Da; Wang, Yingchao; Zheng, Youshi; Peng, Jun; Liu, Xiaolong; Liu, Jingfeng

    2016-01-01

    Tracking and monitoring of cells in vivo after transplantation can provide crucial information for stem cell therapy. Magnetic resonance imaging (MRI) combined with contrast agents is believed to be an effective and non-invasive technique for cell tracking in living bodies. However, commercial superparamagnetic iron oxide nanoparticles (SPIONs) applied to label cells suffer from shortages such as potential toxicity, low labeling efficiency, and low contrast enhancing. Herein, the adipose tissue-derived stem cells (ADSCs) were efficiently labeled with SPIONs coated with poly (dopamine) (SPIONs cluster@PDA), without affecting their viability, proliferation, apoptosis, surface marker expression, as well as their self-renew ability and multi-differentiation potential. The labeled cells transplanted into the mice through tail intravenous injection exhibited a negative enhancement of the MRI signal in the damaged liver-induced by carbon tetrachloride, and subsequently these homed ADSCs with SPIONs cluster@PDA labeling exhibited excellent repair effects to the damaged liver. Moreover, the enhanced target-homing to tissue of interest and repair effects of SPIONs cluster@PDA-labeled ADSCs could be achieved by use of external magnetic field in the excisional skin wound mice model. Therefore, we provide a facile, safe, noninvasive and sensitive method for external magnetic field targeted delivery and MRI based tracking of transplanted cells in vivo.

  8. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summaris...

  9. The External Mind

    DEFF Research Database (Denmark)

    The External Mind: an Introduction by Riccardo Fusaroli, Claudio Paolucci pp. 3-31 The sign of the Hand: Symbolic Practices and the Extended Mind by Massimiliano Cappuccio, Michael Wheeler pp. 33-55 The Overextended Mind by Shaun Gallagher pp. 57-68 The "External Mind": Semiotics, Pragmatism......, Extended Mind and Distributed Cognition by Claudio Paolucci pp. 69-96 The Social Horizon of Embodied Language and Material Symbols by Riccardo Fusaroli pp. 97-123 Semiotics and Theories of Situated/Distributed Action and Cognition: a Dialogue and Many Intersections by Tommaso Granelli pp. 125-167 Building...... Action in Public Environments with Diverse Semiotic Resources by Charles Goodwin pp. 169-182 How Marking in Dance Constitutes Thinking with the Body by David Kirsh pp. 183-214 Ambiguous Coordination: Collaboration in Informal Science Education Research by Ivan Rosero, Robert Lecusay, Michael Cole pp. 215-240...

  10. External-Memory Multimaps

    CERN Document Server

    Angelino, Elaine; Mitzenmacher, Michael; Thaler, Justin

    2011-01-01

    Many data structures support dictionaries, also known as maps or associative arrays, which store and manage a set of key-value pairs. A \\emph{multimap} is generalization that allows multiple values to be associated with the same key. For example, the inverted file data structure that is used prevalently in the infrastructure supporting search engines is a type of multimap, where words are used as keys and document pointers are used as values. We study the multimap abstract data type and how it can be implemented efficiently online in external memory frameworks, with constant expected I/O performance. The key technique used to achieve our results is a combination of cuckoo hashing using buckets that hold multiple items with a multiqueue implementation to cope with varying numbers of values per key. Our external-memory results are for the standard two-level memory model.

  11. Ceramic subsurface marker prototypes

    Energy Technology Data Exchange (ETDEWEB)

    Lukens, C.E. [Rockwell International Corp., Richland, WA (United States). Rockwell Hanford Operations

    1985-05-02

    The client submitted 5 sets of porcelain and stoneware subsurface (radioactive site) marker prototypes (31 markers each set). The following were determined: compressive strength, thermal shock resistance, thermal crazing resistance, alkali resistance, color retention, and chemical resistance.

  12. Visual Analytics for Mobile Eye Tracking.

    Science.gov (United States)

    Kurzhals, Kuno; Hlawatsch, Marcel; Seeger, Christof; Weiskopf, Daniel

    2017-01-01

    The analysis of eye tracking data often requires the annotation of areas of interest (AOIs) to derive semantic interpretations of human viewing behavior during experiments. This annotation is typically the most time-consuming step of the analysis process. Especially for data from wearable eye tracking glasses, every independently recorded video has to be annotated individually and corresponding AOIs between videos have to be identified. We provide a novel visual analytics approach to ease this annotation process by image-based, automatic clustering of eye tracking data integrated in an interactive labeling and analysis system. The annotation and analysis are tightly coupled by multiple linked views that allow for a direct interpretation of the labeled data in the context of the recorded video stimuli. The components of our analytics environment were developed with a user-centered design approach in close cooperation with an eye tracking expert. We demonstrate our approach with eye tracking data from a real experiment and compare it to an analysis of the data by manual annotation of dynamic AOIs. Furthermore, we conducted an expert user study with 6 external eye tracking researchers to collect feedback and identify analysis strategies they used while working with our application.

  13. Track finding efficiency in

    Energy Technology Data Exchange (ETDEWEB)

    Allmendinger, T.; Bhuyan, B.; Brown, D. N.; Choi, H.; Christ, S.; Covarelli, R.; Davier, M.; Denig, A. G.; Fritsch, M.; Hafner, A.; Kowalewski, R.; Long, O.; Lutz, A. M.; Martinelli, M.; Muller, D. R.; Nugent, I. M.; Lopes Pegna, D.; Purohit, M. V.; Prencipe, E.; Roney, J. M.; Simi, G.; Solodov, E. P.; Telnov, A. V.; Varnes, E.; Waldi, R.; Wang, W. F.; White, R. M.

    2012-12-10

    We describe several studies to measure the charged track reconstruction efficiency and asymmetry of the BaBar detector. The first two studies measure the tracking efficiency of a charged particle using τ and initial state radiation decays. The third uses the τ decays to study the asymmetry in tracking, the fourth measures the tracking efficiency for low momentum tracks, and the last measures the reconstruction efficiency of K$0\\atop{S}$ particles. The first section also examines the stability of the measurements vs. BaBar running periods.

  14. Advanced Tracking of Vehicles

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Li, K.-J.; Pakalnis, Stardas

    2005-01-01

    With the continued advances in wireless communications, geo-location technologies, and consumer electronics, it is becoming possible to accurately track the time-varying location of each vehicle in a population of vehicles. This paper reports on ongoing research that has as it objective to develop...... efficient tracking techniques. More specifically, while almost all commercially available tracking solutions simply offer time-based sampling of positions, this paper's techniques aim to offer a guaranteed tracking accuracy for each vehicle at the lowest possible costs, in terms of network traffic...... and server-side updates. This is achieved by designing, prototyping, and testing novel tracking techniques that exploit knowledge of the road network and past movement. These resulting tracking techniques are to support mobile services that rely on the existence of a central server that continuously tracks...

  15. Technical Note: Intrafractional changes in time lag relationship between anterior–posterior external and superior–inferior internal motion signals in abdominal tumor sites

    Energy Technology Data Exchange (ETDEWEB)

    Regmi, Rajesh; Lovelock, D. Michael; Zhang, Pengpeng; Pham, Hai; Xiong, Jianping; Yorke, Ellen D.; Mageras, Gig S., E-mail: magerasg@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 (United States); Goodman, Karyn A.; Wu, Abraham J. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065 (United States)

    2015-06-15

    Purpose: To investigate constancy, within a treatment session, of the time lag relationship between implanted markers in abdominal tumors and an external motion surrogate. Methods: Six gastroesophageal junction and three pancreatic cancer patients (IRB-approved protocol) received two cone-beam CTs (CBCT), one before and one after treatment. Time between scans was less than 30 min. Each patient had at least one implanted fiducial marker near the tumor. In all scans, abdominal displacement (Varian RPM) was recorded as the external motion signal. Purpose-built software tracked fiducials, representing internal signal, in CBCT projection images. Time lag between superior–inferior (SI) internal and anterior–posterior external signals was found by maximizing the correlation coefficient in each breathing cycle and averaging over all cycles. Time-lag-induced discrepancy between internal SI position and that predicted from the external signal (external prediction error) was also calculated. Results: Mean ± standard deviation time lag, over all scans and patients, was 0.10 ± 0.07 s (range 0.01–0.36 s). External signal lagged the internal in 17/18 scans. Change in time lag between pre- and post-treatment CBCT was 0.06 ± 0.07 s (range 0.01–0.22 s), corresponding to 3.1% ± 3.7% (range 0.6%–10.8%) of gate width (range 1.6–3.1 s). In only one patient, change in time lag exceeded 10% of the gate width. External prediction error over all scans of all patients varied from 0.1 ± 0.1 to 1.6 ± 0.4 mm. Conclusions: Time lag between internal motion along SI and external signals is small compared to the treatment gate width of abdominal patients examined in this study. Change in time lag within a treatment session, inferred from pre- to post-treatment measurements is also small, suggesting that a single measurement of time lag at the session start is adequate. These findings require confirmation in a larger number of patients.

  16. Tracks: Nurses and the Tracking Network

    Centers for Disease Control (CDC) Podcasts

    2012-06-06

    This podcast highlights the utility of the National Environmental Public Health Tracking Network for nurses in a variety of work settings. It features commentary from the American Nurses Association and includes stories from a public health nurse in Massachusetts.  Created: 6/6/2012 by National Center for Environmental Health (NCEH)/Division of Environmental Hazards and Health Effects (DEHHE)/Environmental Health Tracking Branch (EHTB).   Date Released: 6/6/2012.

  17. Regularization by External Variables

    DEFF Research Database (Denmark)

    Bossolini, Elena; Edwards, R.; Glendinning, P. A.

    2016-01-01

    Regularization was a big topic at the 2016 CRM Intensive Research Program on Advances in Nonsmooth Dynamics. There are many open questions concerning well known kinds of regularization (e.g., by smoothing or hysteresis). Here, we propose a framework for an alternative and important kind of regula...... of regularization, by external variables that shadow either the state or the switch of the original system. The shadow systems are derived from and inspired by various applications in electronic control, predator-prey preference, time delay, and genetic regulation....

  18. MARKER ASSISTED SELECTION IN DISEASE RESISTANCE BREEDING

    Directory of Open Access Journals (Sweden)

    Narasimhulu Ragimekula

    2013-08-01

    Full Text Available Feeding ever-increasing population is the main challenge faced by the agricultural scientists and to meet this plant breeders have to put continuous efforts to develop new crop varieties on fast track basis. DNA based polymorphism, commonly known as DNA markers can be used for genetic improvement through selection for favourable traits such as disease resistance. Molecular markers are becoming an essential component in backcross breeding programs for tracking the resistance genes in gene pyramiding. Marker assisted selection (MAS, is expected to increase genetic response by affecting efficiency and accuracy of selection. Even though marker-assisted selection now plays a prominent role in the field of plant breeding, examples of successful, practical outcomes are rare. MAS, with few exceptions, has not yet delivered its expected benefits in commercial breeding. It is clear that DNA markers hold great promise, but realizing that promise remains elusive. The economic and biological constraints such as a low return of investment in small-grain cereal breeding, lack of diagnostic markers, and the prevalence of QTL-background effects hinder the broad implementation of MAS. Until complex traits can be fully dissected, the application of MAS will be limited to genes of moderate-to-large effect and to applications that do not endanger the response to conventional selection. Till then, observable phenotype will remain an important component of genetic improvement programmes, because it takes in to account the collective effect of all genes. In future, chip-based, high-throughput genotyping platforms and the introduction of genomic selection will reduce the current problems of integrating MAS in practical breeding programs and open new avenues for a molecular-based resistance breeding.

  19. Comparison of hierarchical and six degrees-of-freedom marker sets in analyzing gait kinematics.

    Science.gov (United States)

    Schmitz, Anne; Buczek, Frank L; Bruening, Dustin; Rainbow, Michael J; Cooney, Kevin; Thelen, Darryl

    2016-01-01

    The objective of this study was to determine how marker spacing, noise, and joint translations affect joint angle calculations using both a hierarchical and a six degrees-of-freedom (6DoF) marker set. A simple two-segment model demonstrates that a hierarchical marker set produces biased joint rotation estimates when sagittal joint translations occur whereas a 6DoF marker set mitigates these bias errors with precision improving with increased marker spacing. These effects were evident in gait simulations where the 6DoF marker set was shown to be more accurate at tracking axial rotation angles at the hip, knee, and ankle.

  20. SWISTRACK - AN OPEN SOURCE, SOFTWARE PACKAGE APPLICABLE TO TRACKING OF FISH LOCOMOTION AND BEHAVIOUR

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2010-01-01

    , Swistrack can be easily adopted for the tracking offish. Benefits associated with the free software include: • Contrast or marker based tracking enabling tracking of either the whole animal, or tagged marks placed upon the animal • The ability to track multiple tags placed upon an individual animal • Highly...... including swimming speed, acceleration and directionality of movements as well as the examination of locomotory panems during swimming. SWiSlrdL:k, a [n: t; and downloadable software package (available from www.sourceforge.com) is widely used for tracking robots, humans and other animals. Accordingly...... effective background subtraction algorithms and filters ensuring smooth tracking of fish • Application of tags of different colour enables the software to track multiple fish without the problem of track exchange between individuals • Low processing requirements enable tracking in real-time • Further...

  1. On Not Losing Track

    OpenAIRE

    Washburn, A.R.

    1990-01-01

    IEEE Transactions on Automatic Control, Vol. 35, 1990, pp. 852-855. This paper uses tracking time as an explicit objective in designing tracking algorithms that function in clutter. Implications of using "time to the first mistake" as a measure of tracking time are explored. An optimal tracker is derived for a special circukstance where there is clutter, but no measurement error, and is compared to a tracker based on the Maximum Likelihood principle.

  2. DCS Budget Tracking System

    Data.gov (United States)

    Social Security Administration — DCS Budget Tracking System database contains budget information for the Information Technology budget and the 'Other Objects' budget. This data allows for monitoring...

  3. Eye tracking disturbances in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Sharma Pradeep

    2000-01-01

    Full Text Available Purpose: To study the frequency of different types of eye tracking disturbances in schizophrenia. Materials and Methods: Smooth pursuit eye movements were studied by electro-oculography (EOG in 22 schizophrenic patients (ICD-10 criteria and 15 age and sex-matched controls. The studied parameters included average pursuit gain, number of saccades, the frequency of different types of saccades (catch-up, back-up, anticipatory saccades, and disturbances during fixation. The results were analysed statistically. Results: The average pursuit gain was significantly affected in patients for target velocity of 30°/sec (p=0.007. The catch-up and back-up saccades were more common in cases than controls but the difference was not significant (p=0.39 and 0.36 respectively. The anticipatory saccades were significantly more frequent in cases than controls (p<0.0001 for both 15°/sec and 30°/sec target velocities. This was also correlated with the duration of illness. Conclusion: Anticipatory saccades are significantly more frequent during eye tracking in schizophrenia and appear to be an objective marker for the disease.

  4. External Measures of Cognition

    Directory of Open Access Journals (Sweden)

    Osvaldo eCairo

    2011-10-01

    Full Text Available The human brain is undoubtedly the most impressive, complex and intricate organ that has evolved over time. It is also probably the least understood, and for that reason, the one that is currently attracting the most attention. In fact, the number of comparative analyses that focus on the evolution of brain size in Homo sapiens and other species has increased dramatically in recent years. In neuroscience, no other issue has generated so much interest and been the topic of so many heated debates as the difference in brain size between socially defined population groups, both its connotations and implications. For over a century, external measures of cognition have been related to intelligence. However, it is still unclear whether these measures actually correspond to cognitive abilities. In summary, this paper must be reviewed with this premise in mind.

  5. 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.

  6. Optimal marker placement in hadrontherapy: intelligent optimization strategies with augmented Lagrangian pattern search

    National Research Council Canada - National Science Library

    Altomare, Cristina; Guglielmann, Raffaella; Riboldi, Marco; Bellazzi, Riccardo; Baroni, Guido

    2015-01-01

    .... Such tracking depends on external fiducial points placement. The main purpose of our work is to propose a new algorithm based on simulated annealing and augmented Lagrangian pattern search (SAPS...

  7. CWI at TREC 2012, KBA track and Session Track

    NARCIS (Netherlands)

    Araújo, S.; Boscarino, C.; Gebremeskel, G.G.; He, J.; Vries, A.P. de; Voorhees, E.M.; Buckland, L. P.

    2013-01-01

    We participated in two tracks: Knowledge Base Acceleration (KBA) Track and Session Track. In the KBA track, we focused on experi- menting with different approaches as it is the first time the track is launched. We experimented with supervised and unsupervised re- trieval models. Our supervised appro

  8. CWI at TREC 2012, KBA track and Session Track

    NARCIS (Netherlands)

    S. Araújo (Samur); C. Boscarino (Corrado); G.G. Gebremeskel (Gebre); J. He (Jiyin); A.P. de Vries (Arjen)

    2013-01-01

    htmlabstractWe participated in two tracks: Knowledge Base Acceleration (KBA) Track and Session Track. In the KBA track, we focused on experi- menting with different approaches as it is the first time the track is launched. We experimented with supervised and unsupervised re- trieval models. Our supe

  9. On the Wrong Track?

    Science.gov (United States)

    Gursky, Daniel

    1990-01-01

    Discusses problems with student tracking. Although supporters consider tracking the best way for teachers to handle classroom diversity, many minorities say that it condemns their children to an inferior education. Studies show that heterogeneous classes benefit all students if the teachers adopt flexible instructional methods to handle the…

  10. Can Tracking Improve Learning?

    Science.gov (United States)

    Duflo, Esther; Dupas, Pascaline; Kremer, Michael

    2009-01-01

    Tracking students into different classrooms according to their prior academic performance is controversial among both scholars and policymakers. If teachers find it easier to teach a homogeneous group of students, tracking could enhance school effectiveness and raise test scores of both low- and high-ability students. If students benefit from…

  11. Can Tracking Improve Learning?

    Science.gov (United States)

    Duflo, Esther; Dupas, Pascaline; Kremer, Michael

    2009-01-01

    Tracking students into different classrooms according to their prior academic performance is controversial among both scholars and policymakers. If teachers find it easier to teach a homogeneous group of students, tracking could enhance school effectiveness and raise test scores of both low- and high-ability students. If students benefit from…

  12. Large scale tracking algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ross L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Love, Joshua Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Melgaard, David Kennett [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Karelitz, David B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pitts, Todd Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zollweg, Joshua David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Anderson, Dylan Z. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nandy, Prabal [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Whitlow, Gary L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bender, Daniel A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Byrne, Raymond Harry [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  13. Incentives from Curriculum Tracking

    Science.gov (United States)

    Koerselman, Kristian

    2013-01-01

    Curriculum tracking creates incentives in the years before its start, and we should therefore expect test scores to be higher during those years. I find robust evidence for incentive effects of tracking in the UK based on the UK comprehensive school reform. Results from the Swedish comprehensive school reform are inconclusive. Internationally, I…

  14. Bewegingsvolgsysteem = Monitor tracking system

    NARCIS (Netherlands)

    Slycke, Per Johan; Veltink, Petrus Hermanus; Roetenberg, Daniel

    2006-01-01

    A motion tracking system for tracking an object composed of object parts in a three-dimensional space. The system comprises a number of magnetic field transmitters; a number of field receivers for receiving the magnetic fields of the field transmitters; a number of inertial measurement units for rec

  15. Bewegingsvolgsysteem = Monitor tracking system

    NARCIS (Netherlands)

    Slycke, Per Johan; Veltink, Petrus Hermanus; Roetenberg, Daniel

    2007-01-01

    A motion tracking system for tracking an object composed of object parts in a three-dimensional space. The system comprises a number of magnetic field transmitters; a number of field receivers for receiving the magnetic fields of the field transmitters; a number of inertial measurement units for rec

  16. Eye-Tracking

    Directory of Open Access Journals (Sweden)

    Gabriela GROSSECK

    2006-01-01

    Full Text Available Eye-tracking: one of the newest and most efficient methods of improving on-line marketing communication is called eye-tracking. Marketers have borrowed this technique, usually used in psychological and medical research, in order to study web users with the help of a video camera incorporated in the monitor.

  17. Large scale tracking algorithms.

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett; Karelitz, David B.; Pitts, Todd Alan; Zollweg, Joshua David; Anderson, Dylan Z.; Nandy, Prabal; Whitlow, Gary L.; Bender, Daniel A.; Byrne, Raymond Harry

    2015-01-01

    Low signal-to-noise data processing algorithms for improved detection, tracking, discrimination and situational threat assessment are a key research challenge. As sensor technologies progress, the number of pixels will increase signi cantly. This will result in increased resolution, which could improve object discrimination, but unfortunately, will also result in a significant increase in the number of potential targets to track. Many tracking techniques, like multi-hypothesis trackers, suffer from a combinatorial explosion as the number of potential targets increase. As the resolution increases, the phenomenology applied towards detection algorithms also changes. For low resolution sensors, "blob" tracking is the norm. For higher resolution data, additional information may be employed in the detection and classfication steps. The most challenging scenarios are those where the targets cannot be fully resolved, yet must be tracked and distinguished for neighboring closely spaced objects. Tracking vehicles in an urban environment is an example of such a challenging scenario. This report evaluates several potential tracking algorithms for large-scale tracking in an urban environment.

  18. Cell tracking. Principles and applications; Cell Tracking. Prinzipien und Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, Jan [Memorial Sloan Kettering Cancer Center, Dept. of Radiology, New York, NY (United States); Kircher, Moritz F. [Beth Israel Deaconess Medical Center/Harvard Medical School, Dept. of Radiology, Boston, MA (United States); Weissleder, Ralph [Massachusetts General Hospital/ Harvard Medical School, Center for Molecular Imaging Research, Boston, MA (United States)

    2007-01-15

    Cell based therapies such as stem cell therapies or adoptive immunotherapies are currently being explored as a potential treatment for a variety of diseases such as Parkinson's disease, diabetes or cancer. However, quantitative and qualitative evaluation of adoptively transferred cells is indispensable for monitoring the efficiency of the treatment. Current approaches mostly analyze transferred cells from peripheral blood, which cannot assess whether transferred cells actuallyhome to and stay in the targeted tissue. Using cell-labeling methods such as direct labeling or transfection with a marker gene in conjunction with various imaging modalities (MRI, optical or nuclear imaging), labeled cells can be followed in vivo in real-time, and their accumulation as well as function in vivo can be monitored and quantified accurately. This method is usually referred to as ''cell tracking'' or ''cell trafficking'' and is also being applied in basic biological sciences, exemplified in the evaluation of genes contributing to metastasis. This review focuses on principles of this promising methodology and explains various approaches by highlighting recent examples. (orig.) [German] Zellulaere Therapieverfahren wie Stammzelltherapien bei Morbus Parkinson oder Diabetes sowie adoptive Immuntherapien bei Krebs werden in Zukunft zunehmend an Bedeutung gewinnen. Ein Problem bei beiden Therapieverfahren stellt jedoch das qualitative und quantitative Monitoring der Therapie dar. Es ist wichtig zu wissen, ob die applizierten Zellen auch zu ihrem Zielgewebe gelangen und darueber hinaus auch noch funktionsfaehig sind. Diese Informationen sind heute meist nur durch invasive Massnahmen wie Blut- oder Gewebeproben zu erlangen. Das Verfahren des ''Cell Tracking'', bei dem entweder direkt oder ueber Markergene markierte Zellen mit verschiedenen bildgebenden Verfahren (MRT, optische oder nuklearmedizinische Verfahren) in vivo

  19. Image-guided navigation surgery for pelvic malignancies using electromagnetic tracking

    Science.gov (United States)

    Nijkamp, Jasper; Kuhlmann, Koert; Sonke, Jan-Jakob; Ruers, Theo

    2016-03-01

    The purpose of this study was to implement and evaluate a surgical navigation system for pelvic malignancies. For tracking an NDI Aurora tabletop field generator and in-house developed navigation software were used. For patient tracking three EM-sensor stickers were used, one on the back and two on the superior iliac spines. During surgery a trackable pointer was used. One day before surgery a CT scan was acquired with the stickers in-place and marked. From the CT scan the EM-sensors, tumor and normal structures were segmented. During surgery, accuracy was independently checked by pointing at the aorta bifurcation and the common iliac artery bifurcations. Subsequently, the system was used to localize the ureters and the tumor. Seven patients were included, three rectal tumors with lymph node-involvement, three lymph node recurrences, and one rectal recurrence. The average external marker registration accuracy was 0.75 cm RMSE (range 0.31-1.58 cm). The average distance between the pointer and the arterial bifurcations was 1.55 cm (1SD=0.63 cm). We were able to localize and confirm the location of all ureters. Twelve out of thirteen lymph nodes were localized and removed. All tumors were removed radically. In all cases the surgeons indicated that the system aided in better anatomical insight, and faster localization of malignant tissue and ureters. In 2/7 cases surgeons indicated that radical resection was only possible with navigation. The navigation accuracy was limited due to the use of skin markers. Nevertheless, preliminary results indicated potential clinical benefit due to better utilization of pre-treatment 3D imaging information.

  20. Identifying external influences on global precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Marvel, K.; Bonfils, C.

    2013-11-11

    Changes in global (ocean and land) precipitation are among the most important and least well-understood consequences of climate change. Increasing greenhouse gas concentrations are thought to affect the zonal-mean distribution of precipitation through two basic mechanisms. First, increasing temperatures will lead to an intensification of the hydrological cycle (“thermodynamic” changes). Second, changes in atmospheric circulation patterns will lead to poleward displacement of the storm tracks and subtropical dry zones and to a widening of the tropical belt (“dynamic” changes). We demonstrate that both these changes are occurring simultaneously in global precipitation, that this behavior cannot be explained by internal variability alone, and that external influences are responsible for the observed precipitation changes. Whereas existing model experiments are not of sufficient length to differentiate between natural and anthropogenic forcing terms at the 95% confidence level, we present evidence that the observed trends result from human activities.

  1. Sparse Hashing Tracking.

    Science.gov (United States)

    Zhang, Lihe; Lu, Huchuan; Du, Dandan; Liu, Luning

    2016-02-01

    In this paper, we propose a novel tracking framework based on a sparse and discriminative hashing method. Different from the previous work, we treat object tracking as an approximate nearest neighbor searching process in a binary space. Using the hash functions, the target templates and the candidates can be projected into the Hamming space, facilitating the distance calculation and tracking efficiency. First, we integrate both the inter-class and intra-class information to train multiple hash functions for better classification, while most classifiers in previous tracking methods usually neglect the inter-class correlation, which may cause the inaccuracy. Then, we introduce sparsity into the hash coefficient vectors for dynamic feature selection, which is crucial to select the discriminative and stable features to adapt to visual variations during the tracking process. Extensive experiments on various challenging sequences show that the proposed algorithm performs favorably against the state-of-the-art methods.

  2. TRACKED VEHICLE Rev 75

    Energy Technology Data Exchange (ETDEWEB)

    2007-05-08

    Revision 75 of the Tracked Vehicle software is a soft real-time simulation of a differentially steered, tracked mobile robot, which, because of the track flippers, resembles the iRobot PackBot (http://www.irobot.com/). Open source libraries are used for the physics engine (http://www.ode.org/), the display and user interface (http://www.mathies.com/cpw/), and the program command line and configuration file parameters (http://www.boost.org/). The simulation can be controlled by a USB joystick or the keyboard. The configuration file contains demonstration model parameters of no particular vehicle. This simulation can be used as a starting point for those doing tracked vehicle simulations. This simulation software is essentially a research tool which can be modified and adapted for certain types of tracked vehicle research. An open source license allows an individual researchers to tailor the code to their specific research needs.

  3. Persistent Aerial Tracking

    KAUST Repository

    Mueller, Matthias

    2016-04-13

    In this thesis, we propose a new aerial video dataset and benchmark for low altitude UAV target tracking, as well as, a photo-realistic UAV simulator that can be coupled with tracking methods. Our benchmark provides the rst evaluation of many state of-the-art and popular trackers on 123 new and fully annotated HD video sequences captured from a low-altitude aerial perspective. Among the compared trackers, we determine which ones are the most suitable for UAV tracking both in terms of tracking accuracy and run-time. We also present a simulator that can be used to evaluate tracking algorithms in real-time scenarios before they are deployed on a UAV "in the field", as well as, generate synthetic but photo-realistic tracking datasets with free ground truth annotations to easily extend existing real-world datasets. Both the benchmark and simulator will be made publicly available to the vision community to further research in the area of object tracking from UAVs. Additionally, we propose a persistent, robust and autonomous object tracking system for unmanned aerial vehicles (UAVs) called Persistent Aerial Tracking (PAT). A computer vision and control strategy is applied to a diverse set of moving objects (e.g. humans, animals, cars, boats, etc.) integrating multiple UAVs with a stabilized RGB camera. A novel strategy is employed to successfully track objects over a long period, by \\'handing over the camera\\' from one UAV to another. We integrate the complete system into an off-the-shelf UAV, and obtain promising results showing the robustness of our solution in real-world aerial scenarios.

  4. Controlled Correspondence Tracking -

    Data.gov (United States)

    Department of Transportation — This data set contains information on external and internal correspondence addressed to the Secretary, Deputy Secretary, or Chief of Staff. Data include information...

  5. External fixators in haemophilia.

    Science.gov (United States)

    Lee, V; Srivastava, A; PalaniKumar, C; Daniel, A J; Mathews, V; Babu, N; Chandy, M; Sundararaj, G D

    2004-01-01

    External fixators (EF) are not commonly used for patients with haemophilia. We describe the use of EF (Ilizarov, AO- uni- and bi-planar fixators and Charnley clamp) in nine patients (mean age: 19.2 years; range: 9-37) with haemophilia for the following indications - arthrodesis of infected joints, treatment of open fractures and osteoclasis. EF required an average of nine skin punctures [range: 4-17 were maintained for a period of 15 weeks (range: 8-29.5), without regular factor replacement, till bone healing was adequate and were removed with a single dose of factor infusion]. The mean preoperative factor level achieved was 85% (range: 64-102%). Much lower levels were subsequently maintained till wound healing. The average total factor consumption was 430 IU kg(-1) (range: 240-870), administered over a period of 17 days (range: 9-44). There were no major complications related to EF except in a patient who developed inhibitors. In conclusion, EF can be used safely in haemophilic patients who do not have inhibitors and does not require prolonged factor replacement.

  6. Skepticism, contextualism, externalism and modality

    National Research Council Canada - National Science Library

    Ron Wilburn

    2006-01-01

    .... However, because efforts to contextualize externalism via subjunctive conditional analysis court circularity, it is only on an internalistic interpretation that contextualist strategies can even be motivated...

  7. Molecular markers and sentinel organisms for environmental monitoring

    Directory of Open Access Journals (Sweden)

    Graczyk T.K.

    2008-09-01

    Full Text Available Molecular methods are useful for both to monitor anthropogenic viral, bacterial, and protozoan enteropathogens, and to track pathogen specific markers in a complex environment in order to reveal sources of these pathogens. Molecular genetic markers for fecal viruses, bacteria, and protozoans hold promise for monitoring environmental pollution and water quality. The demand for microbiologically safe waters grows exponentially due to the global demographic rise of the human population. Economically important shellfish, such as oysters, which are harvested commercially and preferentially consumed raw can be of public health importance if contaminated with human waterborne pathogens. However, feral molluscan shellfish which do not have an apparent economic value serve as indicators in monitoring aquatic environments for pollution with human waterborne pathogens and for sanitary assessment of water quality. Current technology allows for multiplexed species-specific identification, genotyping, enumeration, viability assessment, and source-tracking of human enteropathogens which considerably enhances the pathogen source-tracking efforts.

  8. Markerless motion tracking of awake animals in positron emission tomography.

    Science.gov (United States)

    Kyme, Andre; Se, Stephen; Meikle, Steven; Angelis, Georgios; Ryder, Will; Popovic, Kata; Yatigammana, Dylan; Fulton, Roger

    2014-11-01

    Noninvasive functional imaging of awake, unrestrained small animals using motion-compensation removes the need for anesthetics and enables an animal's behavioral response to stimuli or administered drugs to be studied concurrently with imaging. While the feasibility of motion-compensated radiotracer imaging of awake rodents using marker-based optical motion tracking has been shown, markerless motion tracking would avoid the risk of marker detachment, streamline the experimental workflow, and potentially provide more accurate pose estimates over a greater range of motion. We have developed a stereoscopic tracking system which relies on native features on the head to estimate motion. Features are detected and matched across multiple camera views to accumulate a database of head landmarks and pose is estimated based on 3D-2D registration of the landmarks to features in each image. Pose estimates of a taxidermal rat head phantom undergoing realistic rat head motion via robot control had a root mean square error of 0.15 and 1.8 mm using markerless and marker-based motion tracking, respectively. Markerless motion tracking also led to an appreciable reduction in motion artifacts in motion-compensated positron emission tomography imaging of a live, unanesthetized rat. The results suggest that further improvements in live subjects are likely if nonrigid features are discriminated robustly and excluded from the pose estimation process.

  9. Real-time tracking for virtual environments using scaat kalman filtering and unsynchronised cameras

    DEFF Research Database (Denmark)

    Rasmussen, Niels Tjørnly; Störring, Morritz; Moeslund, Thomas B.

    2006-01-01

    This paper presents a real-time outside-in camera-based tracking system for wireless 3D pose tracking of a user’s head and hand in a virtual environment. The system uses four unsynchronised cameras as sensors and passive retroreflective markers arranged in rigid bodies as targets. In order...

  10. Embryonic Stem Cell Markers

    Directory of Open Access Journals (Sweden)

    Lan Ma

    2012-05-01

    Full Text Available Embryonic stem cell (ESC markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM technique and magnetic cell sorting (MACS are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs, which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

  11. Marker development in ornamental plants

    NARCIS (Netherlands)

    Heusden, van A.W.; Arens, P.

    2009-01-01

    Development of markers for a new crop or development of additional markers for a crop where markers have been developed in the past raises the question of the intended use of the markers. Depending on the different objectives in mind one marker type may be better suited then another. In general one

  12. Use of wand markers on the pelvis in three dimensional gait analysis

    DEFF Research Database (Denmark)

    Smith, Martin; Curtis, Derek; Bencke, Jesper

    2013-01-01

    During clinical gait analysis, surface markers are placed over the anterior superior iliac spines (ASIS) of the pelvis. However, this can be problematic in overweight or obese subjects, where excessive adipose tissue can obscure the markers and prevent accurate tracking. A novel solution to this ...

  13. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summaris...... how the methodology has been applied so far in a previous Danish study. Finally, results of a case study are reported. Exposure factors have been calculated for various urban categories in the Greater Copenhagen Area...

  14. ExternE transport methodology for external cost evaluation of air pollution (DK)

    Energy Technology Data Exchange (ETDEWEB)

    Solvang Jensen, S.; Berkowicz, R.; Brandt, J. [National Environmental Research Inst., Dept. of Atmospheric Environment (Denmark); Willumsen, E.; Kristensen, N.B. [COWI (Denmark)

    2004-07-01

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AiGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Inititally, a brief description of the ExternE Transport methodology is given and it is summarised how the methodology has been applied so far in a previous Danish study. Finally, results of a case study are reported. Exposure factors have been calculated for various urban categories in the Greater Copenhagen Area. (au)

  15. External coating of colonic anastomoses

    DEFF Research Database (Denmark)

    Pommergaard, Hans-Christian; Achiam, Michael Patrick; Rosenberg, Jacob

    2012-01-01

    Colon anastomotic leakage remains both a frequent and serious complication in gastrointestinal surgery. External coating of colonic anastomoses has been proposed as a means to lower the rate of this complication. The aim of this review was to evaluate existing studies on external coating of colonic...

  16. Retrofitting Systems for External Walls

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report, 9 different external and internal retrofitting systems are analyzed using numerical calculations. The analysis focuses on the thermal bridge effects in the different systems, and on this basis it is discussed whether internal or external retrofitting has the most advantages...

  17. Human Capital Tracking Tool -

    Data.gov (United States)

    Department of Transportation — AVS is now required to collect, track, and report on data from the following Flight, Business and Workforce Plan. The Human Resource Management’s Performance Target...

  18. Track Loading Vehicle - TLV

    Data.gov (United States)

    Federal Laboratory Consortium — The TLV is designed to apply forces close to the strength limits of the rails and other track structure components, such as ties, rail fasteners, and ballast, while...

  19. 1996 : Track Count Protocol

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The goal of St. Vincent National Wildlife Refuge's Track Count Protocol is to provide an index to the population size of game animals inhabiting St. Vincent Island.

  20. Case Analysis Tracking System

    Data.gov (United States)

    National Archives and Records Administration — CATS tracks Public and Federal Agency Reference Requests for OPF (Official Personnel Folder) , EMF (Employee Medical Folder), and eOPF (electronic Official Personnel...

  1. Financial Disclosure Tracking System

    Data.gov (United States)

    US Agency for International Development — USAID's FDTS identifies personal service contractors and local employees who should file disclosure reports. It tracks late filers and identifies those who must take...

  2. Matter Tracking Information System -

    Data.gov (United States)

    Department of Transportation — The Matter Tracking Information System (MTIS) principle function is to streamline and integrate the workload and work activity generated or addressed by our 300 plus...

  3. Neonate turtle tracking data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The objectives of this project are to use novel satellite tracking methods to provide improved estimation of threats at foraging areas and along migration routes for...

  4. LHCb on track

    CERN Multimedia

    2006-01-01

    On 7 and 8 June 2006, the last large component of the LHCb experiment was lowered into the cavern. This 10-tonne, 18-metre long metal structure known as 'the bridge' will support the LHCb tracking system.

  5. Patient Treatment Tracking Chart

    Science.gov (United States)

    ... Treatment Tracking Chart Viral Hepatitis Menu Menu Viral Hepatitis Viral Hepatitis Home For Veterans and the Public Veterans ... can record dates of blood work, laboratory values, hepatitis C viral load levels, medication dosages, and side effects. You ...

  6. Energy Tracking Software Platform

    Energy Technology Data Exchange (ETDEWEB)

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  7. Tracking Performance at LHCb

    CERN Multimedia

    Wandernoth, S

    2010-01-01

    We present the tracking performance at LHCb by showing the mass resolution, impact parameter resolution and proper time resolution of the first data taken at LHCb. Furthermore several methods to estimate the tagging efficiency on data are presented.

  8. Procurement Tracking System (PTS)

    Data.gov (United States)

    Office of Personnel Management — The Procurement Tracking System (PTS) is used solely by the procurement staff of the Office of the Inspector General (OIG) at the U.S. Office of Personnel Management...

  9. LHCb VELO Tracking Resolutions

    CERN Multimedia

    Alexander, Michael

    2011-01-01

    The excellent tracking performance of the Vertex Locator (VELO) at LHCb is presented. The resolutions it achieves on single hits, impact parameters, and primary vertex positions are shown, with particular attention paid to measurement of impact parameters.

  10. Applied eye tracking research

    NARCIS (Netherlands)

    Jarodzka, Halszka

    2011-01-01

    Jarodzka, H. (2010, 12 November). Applied eye tracking research. Presentation and Labtour for Vereniging Gewone Leden in oprichting (VGL i.o.), Heerlen, The Netherlands: Open University of the Netherlands.

  11. Jet Car Track Site

    Data.gov (United States)

    Federal Laboratory Consortium — Located in Lakehurst, New Jersey, the Jet Car Track Site supports jet cars with J57 engines and has a maximum jet car thrust of 42,000 pounds with a maximum speed of...

  12. Applied eye tracking research

    NARCIS (Netherlands)

    Jarodzka, Halszka

    2011-01-01

    Jarodzka, H. (2010, 12 November). Applied eye tracking research. Presentation and Labtour for Vereniging Gewone Leden in oprichting (VGL i.o.), Heerlen, The Netherlands: Open University of the Netherlands.

  13. Performance Targets and External Benchmarking

    DEFF Research Database (Denmark)

    Friis, Ivar; Hansen, Allan; Vámosi, Tamás S.

    Research on relative performance measures, transfer pricing, beyond budgeting initiatives, target costing, piece rates systems and value based management has for decades underlined the importance of external benchmarking in performance management. Research conceptualises external benchmarking...... the conditions upon which the market mechanism is performing within organizations. This paper aims to contribute to research by providing more insight to the conditions for the use of external benchmarking as an element in performance management in organizations. Our study explores a particular type of external...... towards the conditions for the use of the external benchmarks we provide more insights to some of the issues and challenges that are related to using this mechanism for performance management and advance competitiveness in organizations....

  14. Human pose tracking by parametric annealing

    CERN Document Server

    Kaliamoorthi, Prabhu

    2012-01-01

    Model based methods to marker-free motion capture have a very high computational overhead that make them unattractive. In this paper we describe a method that improves on existing global optimization techniques to tracking articulated objects. Our method improves on the state-of-the-art Annealed Particle Filter (APF) by reusing samples across annealing layers and by using an adaptive parametric density for diffusion. We compare the proposed method with APF on a scalable problem and study how the two methods scale with the dimensionality, multi-modality and the range of search. Then we perform sensitivity analysis on the parameters of our algorithm and show that it tolerates a wide range of parameter settings. We also show results on tracking human pose from the widely-used Human Eva I dataset. Our results show that the proposed method reduces the tracking error despite using less than 50% of the computational resources as APF. The tracked output also shows a significant qualitative improvement over APF as dem...

  15. Function integrated track system

    OpenAIRE

    Hohnecker, Eberhard

    2010-01-01

    The paper discusses a function integrated track system that focuses on the reduction of acoustic emissions from railway lines. It is shown that the combination of an embedded rail system (ERS), a sound absorbing track surface, and an integrated mini sound barrier has significant acoustic advantages compared to a standard ballast superstructure. The acoustic advantages of an embedded rail system are particularly pronounced in the case of railway bridges. Finally, it is shown that a...

  16. Vehicle Tracking and Security

    Science.gov (United States)

    Scorer, A. G.

    1998-09-01

    This paper covers the wide area and short range locational technologies that are available for vehicle tracking in particular and mobile user security in general. It also summarises the radio communications services that can deliver information to the user. It considers the use that can be made of these technologies, when combined with procedures for delivering a response, in the security field, notably in relation to personal security, high-value load protection and the after-theft tracking markets.

  17. Provenance Tracking in UNICORE

    OpenAIRE

    Giesler, André; Hagemeier, Björn; Czekala, Myriam

    2015-01-01

    The automated tracking and storage of provenance information allows users of scientific workflow systems to validate and reproduce results of their experiments. Until now, UNICORE has not been providing comprehensive provenance features. For this reason, we plan to equip UNICORE with a flexible provenance tracking mechanism. Our goal is to ensure a suitable traceability of job and workflow processes into a description format supporting query capabilities and interoperability. In a first step,...

  18. Cardiac Mechanics Evaluated by Speckle Tracking Echocardiography

    Science.gov (United States)

    Abduch, Maria Cristina Donadio; Alencar, Adriano Mesquita; Mathias, Wilson; Vieira, Marcelo Luiz de Campos

    2014-01-01

    Natural myocardial markers, or speckles, originated from constructive and destructive interference of ultrasound in the tissues may provide early diagnosis of myocardial changes and be used in the prediction of some cardiac events. Due to its relatively temporal stability, speckles can be tracked by dedicated software along the cardiac cycle, enabling the analysis of the systolic and diastolic function. They are identified by either conventional 2D grey scale and by 3D echo, conferring independence of the insonation angle, thus allowing assessment of cardiac mechanics in the three spatial planes: longitudinal, circumferential, and radial. The purposes of the present paper are: to discuss the role and the meaning of cardiac strain obtained by speckle tracking during the evaluation of cardiac physiology and to discuss clinical applications of this novel echocardiographic technology. PMID:24844877

  19. MATERIAL TRACKING USING LANMAS

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, F.

    2010-06-07

    LANMAS is a transaction-based nuclear material accountability software product developed to replace outdated and legacy accountability systems throughout the DOE. The core underlying purpose of LANMAS is to track nuclear materials inventory and report transactions (movement, mixing, splitting, decay, etc.) to the Nuclear Materials Management and Safeguards System (NMMSS). While LANMAS performs those functions well, there are many additional functions provided by the software product. As a material is received onto a site or created at a site, its entire lifecycle can be tracked in LANMAS complete to its termination of safeguards. There are separate functions to track material movements between and within material balance areas (MBAs). The level of detail for movements within a MBA is configurable by each site and can be as high as a site designation or as detailed as building/room/rack/row/position. Functionality exists to track the processing of materials, either as individual items or by modeling a bulk process as an individual item to track inputs and outputs from the process. In cases where sites have specialized needs, the system is designed to be flexible so that site specific functionality can be integrated into the product. This paper will demonstrate how the software can be used to input material into an account and track it to its termination of safeguards.

  20. VT Roadside Historic Markers

    Data.gov (United States)

    Vermont Center for Geographic Information — Roadside Historic Site Marker program has proven an effective way to commemorate Vermont’s many people, events, and places of regional, statewide, or national...

  1. Fiducial Marker Placement

    Science.gov (United States)

    ... Media Computed Tomography (CT) - Body General Ultrasound Ultrasound - Prostate Introduction to Cancer Therapy (Radiation Oncology) Proton Therapy Stereotactic Radiosurgery (SRS) and Stereotactic Body Radiotherapy (SBRT) Images related to Fiducial Marker Placement Sponsored by ...

  2. Visual Servoing of a Conventional CNC Machine Using an External Axis Controller

    Directory of Open Access Journals (Sweden)

    Daniel Hanafi

    2003-04-01

    Full Text Available This paper presents the implementation of an external axis control system on a conventional CNC machine so that the machine can be actively controlled in response to sensors such as vision and force. The controller that runs on an external computer has direct access to the CNC controller for machine position sensing. The control signals to the machine are sent through purpose built circuitry via the machine's manual pulse generator (MPG inputs. To demonstrate the accuracy and performance of the control system, it was used to visually track the profile of a mandrel used for shear spinning. The implemented system eliminates the parallax error and the need to use an accurate pixel resolution. The raw tracking data is processed by a curvature detection algorithm that detects linear and circular segments and segment transitions. The results show that the visual tracking system provides accurate tracking results that are well within the tolerances used in the industry.

  3. Suitability of markerless EPID tracking for tumor position verification in gated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Serpa, Marco [Institute for Research and Development on Advanced Radiation Technologies (radART), Paracelsus Medical University, 5020 Salzburg (Austria); University Clinic for Radiotherapy and Radio-Oncology, Landeskrankenhaus Salzburg, Paracelsus Medical University Clinics, 5020 Salzburg (Austria); Department of Physics and Astronomy, University of Canterbury, Christchurch 8140 (New Zealand); Baier, Kurt; Guckenberger, Matthias [Department of Radiation Oncology, University of Wuerzburg, D-97080 Wuerzburg (Germany); Cremers, Florian [Department of Radiation Oncology, University Medical Center Hamburg Eppendorf, D-20246 Hamburg (Germany); Meyer, Juergen, E-mail: juergen@uw.edu [Department of Radiation Oncology, University of Washington, Seattle, Washington 98195 (United States)

    2014-03-15

    Purpose: To maximize the benefits of respiratory gated radiotherapy (RGRT) of lung tumors real-time verification of the tumor position is required. This work investigates the feasibility of markerless tracking of lung tumors during beam-on time in electronic portal imaging device (EPID) images of the MV therapeutic beam. Methods: EPID movies were acquired at ∼2 fps for seven lung cancer patients with tumor peak-to-peak motion ranges between 7.8 and 17.9 mm (mean: 13.7 mm) undergoing stereotactic body radiotherapy. The external breathing motion of the abdomen was synchronously measured. Both datasets were retrospectively analyzed inPortalTrack, an in-house developed tracking software. The authors define a three-step procedure to run the simulations: (1) gating window definition, (2) gated-beam delivery simulation, and (3) tumor tracking. First, an amplitude threshold level was set on the external signal, defining the onset of beam-on/-off signals. This information was then mapped onto a sequence of EPID images to generate stamps of beam-on/-hold periods throughout the EPID movies in PortalTrack, by obscuring the frames corresponding to beam-off times. Last, tumor motion in the superior-inferior direction was determined on portal images by the tracking algorithm during beam-on time. The residual motion inside the gating window as well as target coverage (TC) and the marginal target displacement (MTD) were used as measures to quantify tumor position variability. Results: Tumor position monitoring and estimation from beam's-eye-view images during RGRT was possible in 67% of the analyzed beams. For a reference gating window of 5 mm, deviations ranging from 2% to 86% (35% on average) were recorded between the reference and measured residual motion. TC (range: 62%–93%; mean: 77%) losses were correlated with false positives incidence rates resulting mostly from intra-/inter-beam baseline drifts, as well as sudden cycle-to-cycle fluctuations in exhale positions

  4. Tracking time-varying coefficient-functions

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg; Nielsen, Torben Skov; Joensen, Alfred K.;

    2000-01-01

    is a combination of recursive least squares with exponential forgetting and local polynomial regression. It is argued, that it is appropriate to let the forgetting factor vary with the value of the external signal which is the argument of the coefficient functions. Some of the key properties of the modified method......, but otherwise unknown, functions of a low-dimensional input process. These coefficient functions are estimated adaptively and recursively without specifying a global parametric, form, i.e. the method allows for online tracking of the coefficient functions. Essentially, in its most simple form, the method...

  5. Marker development in ornamental plants

    OpenAIRE

    2009-01-01

    Development of markers for a new crop or development of additional markers for a crop where markers have been developed in the past raises the question of the intended use of the markers. Depending on the different objectives in mind one marker type may be better suited then another. In general one can think of two main objectives for the use of markers; variety identification and breeding applications. In view of recent developments in molecular genetics, and sequencing technologies in parti...

  6. Robust augmented reality guidance with fluorescent markers in laparoscopic surgery.

    Science.gov (United States)

    Wild, Esther; Teber, Dogu; Schmid, Daniel; Simpfendörfer, Tobias; Müller, Michael; Baranski, Ann-Christin; Kenngott, Hannes; Kopka, Klaus; Maier-Hein, Lena

    2016-06-01

    Laparoscopic interventions require the precise navigation of medical instruments through the patient's body, while taking critical structures into account. Although numerous concepts have been proposed for displaying subsurface anatomical detail using augmented reality, clinical translation of these methods has suffered from a lack of robustness as well as from cumbersome integration into the clinical workflow. The purpose of this study was to investigate the feasibility of a new approach to intra-operative registration based on fluorescent markers. The proposed approach to augmented reality visualization relies on metabolizable fluorescent markers that are attached to the target organ to guide a 2D/3D intra-operative registration algorithm. In an ex vivo porcine study, marker tracking performance is evaluated in the presence of smoke, blood, and tissue in the field of view of the endoscope. In contrast to state-of-the-art needle-shaped fiducial markers, the fluorescent markers can be reliably tracked when occluded by smoke, blood or tissue. This makes the new 2D/3D intra-operative registration approach considerably more robust than state-of-the-art marker-based methods. As the concept can be smoothly integrated into the clinical workflow, its potential for application in clinical laparoscopy is high.

  7. Effectiveness of an Automatic Tracking Software in Underwater Motion Analysis

    Directory of Open Access Journals (Sweden)

    Fabrício A. Magalhaes

    2013-12-01

    Full Text Available Tracking of markers placed on anatomical landmarks is a common practice in sports science to perform the kinematic analysis that interests both athletes and coaches. Although different software programs have been developed to automatically track markers and/or features, none of them was specifically designed to analyze underwater motion. Hence, this study aimed to evaluate the effectiveness of a software developed for automatic tracking of underwater movements (DVP, based on the Kanade-Lucas-Tomasi feature tracker. Twenty-one video recordings of different aquatic exercises (n = 2940 markers’ positions were manually tracked to determine the markers’ center coordinates. Then, the videos were automatically tracked using DVP and a commercially available software (COM. Since tracking techniques may produce false targets, an operator was instructed to stop the automatic procedure and to correct the position of the cursor when the distance between the calculated marker’s coordinate and the reference one was higher than 4 pixels. The proportion of manual interventions required by the software was used as a measure of the degree of automation. Overall, manual interventions were 10.4% lower for DVP (7.4% than for COM (17.8%. Moreover, when examining the different exercise modes separately, the percentage of manual interventions was 5.6% to 29.3% lower for DVP than for COM. Similar results were observed when analyzing the type of marker rather than the type of exercise, with 9.9% less manual interventions for DVP than for COM. In conclusion, based on these results, the developed automatic tracking software presented can be used as a valid and useful tool for underwater motion analysis.

  8. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L.; Sieverts Nielsen, P.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results; to aggregate these site- and technology-specific results to more general figures. The current report covers the results of the national implementation for Denmark. Three different fuel cycles have been chosen as case studies. These are fuel cycles for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant based on biogas. The report covers all the details of the application of the methodology to these fuel cycles aggregation to a national level. (au) EU-JOULE 3. 59 tabs., 25 ills., 61 refs.

  9. PD-type iterative learning control for nonlinear time-delay system with external disturbance

    Institute of Scientific and Technical Information of China (English)

    Zhang Baolin; Tang Gongyou; Zheng Shi

    2006-01-01

    The PD-type iterative learning control design of a class of affine nonlinear time-delay systems with external disturbances is considered. Sufficient conditions guaranteeing the convergence of the n-norm of the tracking error are derived. It is shown that the system outputs can be guaranteed to converge to desired trajectories in the absence of external disturbances and output measurement noises. And in the presence of state disturbances and measurement noises, the tracking error will be bounded uniformly. A numerical simulation example is presented to validate the effectiveness of the proposed scheme.

  10. External fuel thermionic reactor system.

    Science.gov (United States)

    Mondt, J. F.; Peelgren, M. L.

    1971-01-01

    Thermionic reactors are prime candidates for nuclear electric propulsion. The national thermionic reactor effort is concentrated on the flashlight concept with the external-fuel concept as the backup. The external-fuel concept is very adaptable to a completely modular power subsystem which is attractive for highly reliable long-life applications. The 20- to 25-cm long, externally-fueled converters have been designed, fabricated, and successfully tested with many thermal cycles by electrical heating. However, difficulties have been encountered during encapsulation for nuclear heated tests and none have been started to date. These nuclear tests are required to demonstrate the concept feasibility.

  11. Using surface markers for MRI guided breast conserving surgery: a feasibility survey

    Science.gov (United States)

    Ebrahimi, Mehran; Siegler, Peter; Modhafar, Amen; Holloway, Claire M. B.; Plewes, Donald B.; Martel, Anne L.

    2014-04-01

    Breast MRI is frequently performed prior to breast conserving surgery in order to assess the location and extent of the lesion. Ideally, the surgeon should also be able to use the image information during surgery to guide the excision and this requires that the MR image is co-registered to conform to the patient’s position on the operating table. Recent progress in MR imaging techniques has made it possible to obtain high quality images of the patient in the supine position which significantly reduces the complexity of the registration task. Surface markers placed on the breast during imaging can be located during surgery using an external tracking device and this information can be used to co-register the images to the patient. There remains the problem that in most clinical MR scanners the arm of the patient has to be placed parallel to the body whereas the arm is placed perpendicular to the patient during surgery. The aim of this study is to determine the accuracy of co-registration based on a surface marker approach and, in particular, to determine what effect the difference in a patient’s arm position makes on the accuracy of tumour localization. Obtaining a second MRI of the patient where the patient’s arm is perpendicular to body axes (operating room position) is not possible. Instead we obtain a secondary MRI scan where the patient’s arm is above the patient’s head to validate the registration. Five patients with enhancing lesions ranging from 1.5 to 80 cm3 in size were imaged using contrast enhanced MRI with their arms in two positions. A thin-plate spline registration scheme was used to match these two configurations. The registration algorithm uses the surface markers only and does not employ the image intensities. Tumour outlines were segmented and centre of mass (COM) displacement and Dice measures of lesion overlap were calculated. The relationship between the number of markers used and the COM-displacement was also studied. The lesion COM

  12. Combination of external loads

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S.; Tarp Johansen, N.J.; Joergensen, H. [Forskningscenter Risoe, Roskilde (Denmark); Gravesen, H.; Soerensen, S.L. [Carl Bro, Glostrup (Denmark); Pedersen, J. [Elsam Engineering, Fredericia (Denmark); Zorn, R.; Hvidberg Knudsen, M. [DHI Water and Environment, Hoersholm (Denmark); Voelund, P. [Energi E2, Koebenhavn (Denmark)

    2003-09-01

    The project onbectives have been: To improve and consequently opimise the basis for design of offshore wind turbines. This is done through 1) mapping the wind, wave ice and current as well as correlations of these, and 2) by clarifyring how these external conditions transform into loads. A comprehensive effort has been made to get a thorough understanding of the uncertainties that govern the reliability of wind turbines with respect to wind and wave loading. One of the conclusions is that the reliability of wind turbines is generally lower, than the average reliability of building structures that are subject not only to environmental loads, which are very uncertain, but also imposed loads and self weight, which are less uncertain than the environmental loads. The implication is that, at the moment lower load partial safety factors for onshore wind turbines cannot be recommended. For the combination of wind and wave design loads the problem is twofold: 1). A very conservative design will be generated by simply adding the individual wind and wave design loads disregarding the independence of the short-term fluctuations of wind and wave loads. 2). Characteristic values and partial safety factors for wind and wave loads are not defined similarly. This implies that the reliability levels of turbine support structures subject to purely aerodynamic loads and subject to purely hydrodynamic loads are not identical. For the problem of combining aerodynamic design loads and hydrodynamic design loads two results have been obtained in the project: 1). By simple means a site specific wave load safety factor rendering the same safety level for hydrodynamic loads as for aerodynamic loads is derived, and next, by direct square summation of extreme fluctuations, the wind and wave load safety factors are weighted. 2). Under the assumptions that a deep water site is considered and that the wave loading is a fifty-fifty mix of drag and inertia the same wind and wave load safety factor

  13. Active Multimodal Sensor System for Target Recognition and Tracking.

    Science.gov (United States)

    Qu, Yufu; Zhang, Guirong; Zou, Zhaofan; Liu, Ziyue; Mao, Jiansen

    2017-06-28

    High accuracy target recognition and tracking systems using a single sensor or a passive multisensor set are susceptible to external interferences and exhibit environmental dependencies. These difficulties stem mainly from limitations to the available imaging frequency bands, and a general lack of coherent diversity of the available target-related data. This paper proposes an active multimodal sensor system for target recognition and tracking, consisting of a visible, an infrared, and a hyperspectral sensor. The system makes full use of its multisensor information collection abilities; furthermore, it can actively control different sensors to collect additional data, according to the needs of the real-time target recognition and tracking processes. This level of integration between hardware collection control and data processing is experimentally shown to effectively improve the accuracy and robustness of the target recognition and tracking system.

  14. Luge Track Safety

    CERN Document Server

    Hubbard, Mont

    2012-01-01

    Simple geometric models of ice surface shape and equations of motion of objects on these surfaces can be used to explain ejection of sliders from ice tracks. Simulations using these can be used to explain why certain design features can be viewed as proximate causes of ejection from the track and hence design flaws. This paper studies the interaction of a particle model for the luge sled (or its right runner) with the ice fillet commonly connecting inside vertical walls and the flat track bottom. A numerical example analyzes the 2010 luge accident at the Vancouver Olympics. It shows that this runner-fillet interaction, and specifically the fillet's positive curvature up the inside wall, can cause a vertical velocity more than sufficient to clear the outside exit wall. In addition its negative curvature along the track, together with large vertical velocity, explains loss of fillet or wall contact and slider ejection. This exposes the fillet along inside walls as a track design flaw. A more transparent design ...

  15. Clean tracks for ATLAS

    CERN Multimedia

    2006-01-01

    First cosmic ray tracks in the integrated ATLAS barrel SCT and TRT tracking detectors. A snap-shot of a cosmic ray event seen in the different layers of both the SCT and TRT detectors. The ATLAS Inner Detector Integration Team celebrated a major success recently, when clean tracks of cosmic rays were detected in the completed semiconductor tracker (SCT) and transition radiation tracker (TRT) barrels. These tracking tests come just months after the successful insertion of the SCT into the TRT (See Bulletin 09/2006). The cosmic ray test is important for the experiment because, after 15 years of hard work, it is the last test performed on the fully assembled barrel before lowering it into the ATLAS cavern. The two trackers work together to provide millions of channels so that particles' tracks can be identified and measured with great accuracy. According to the team, the preliminary results were very encouraging. After first checks of noise levels in the final detectors, a critical goal was to study their re...

  16. Markers of erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Kelvin P Davies

    2008-01-01

    Full Text Available With the development and marketing of oral pharmacotherapy that is both noninvasive and successful in treating erectile dysfunction (ED, the quest to identify markers of organic ED lost ground. Indeed, the multi-factorial nature of ED may have led many researchers to conclude that searching for a universal marker of ED was futile. However, the realization that ED is strongly correlated with the overall health of men, and may act as a predictor for the development of cardiovascular disease (CVD and diabetes, has stimulated interest in identifying genes that can distinguish organic ED. In addition, the potential ability to suggest to the patient that ED is reversible (i.e., psychogenic with a simple test would be of significance to both the physician and patient, as well as for reimbursement issues for therapy by insurance companies. Such a marker may also act as a non-subjective measure of the degree of ED and the efficacy of treatment. This review discusses the importance of identifying such markers and recent work identifying potential markers in human patients.

  17. External costs related to power production technologies. ExternE national implementation for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Schleisner, L.; Sieverts Nielsen, P. [eds.

    1997-12-01

    The objective of the ExternE National Implementation project has been to establish a comprehensive and comparable set of data on externalities of power generation for all EU member states and Norway. The tasks include the application of the ExternE methodology to the most important fuel cycles for each country as well as to update the already existing results, to aggregate these site- and technology-specific results to more general figures. The current report covers the detailed information concerning the ExternE methodology. Importance is attached to the computer system used in the project and the assessment of air pollution effects on health, materials and ecological effects. Also the assessment of global warming damages are described. Finally the report covers the detailed information concerning the national implementation for Denmark for an offshore wind farm and a wind farm on land, a decentralised CHP plant based on natural gas and a decentralised CHP plant base on biogas. (au) EU-JOULE 3. 79 tabs., 11 ills., 201 refs.

  18. Computer program TRACK_TEST for calculating parameters and plotting profiles for etch pits in nuclear track materials

    Science.gov (United States)

    Nikezic, D.; Yu, K. N.

    2006-01-01

    A computer program called TRACK_TEST for calculating parameters (lengths of the major and minor axes) and plotting profiles in nuclear track materials resulted from light-ion irradiation and subsequent chemical etching is described. The programming steps are outlined, including calculations of alpha-particle ranges, determination of the distance along the particle trajectory penetrated by the chemical etchant, calculations of track coordinates, determination of the lengths of the major and minor axes and determination of the contour of the track opening. Descriptions of the program are given, including the built-in V functions for the two commonly employed nuclear track materials commercially known as LR 115 (cellulose nitrate) and CR-39 (poly allyl diglycol carbonate) irradiated by alpha particles. Program summaryTitle of the program:TRACK_TEST Catalogue identifier:ADWT Program obtainable from:CPC Program Library, Queen's University of Belfast, N. Ireland Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWT Computer:Pentium PC Operating systems:Windows 95+ Programming language:Fortran 90 Memory required to execute with typical data:256 MB No. of lines in distributed program, including test data, etc.: 2739 No. of bytes in distributed program, including test data, etc.:204 526 Distribution format:tar.gz External subprograms used:The entire code must be linked with the MSFLIB library Nature of problem: Fast heavy charged particles (like alpha particles and other light ions etc.) create latent tracks in some dielectric materials. After chemical etching in aqueous NaOH or KOH solutions, these tracks become visible under an optical microscope. The growth of a track is based on the simultaneous actions of the etchant on undamaged regions (with the bulk etch rate V) and along the particle track (with the track etch rate V). Growth of the track is described satisfactorily by these two parameters ( V and V). Several models have been presented in the past describing

  19. Externality and burnout among dentists.

    Science.gov (United States)

    St-Yves, A; Freeston, M H; Godbout, F; Poulin, L; St-Amand, C; Verret, M

    1989-12-01

    This study investigates the relationship between burnout as measured by the Maslach Burnout Inventory and locus of control as measured by the Adult Nowicki-Strickland Internal-External Locus of Control (ANS-IE) for 82 dentists. Significant Pearson correlations between two Maslach subscales and locus of control show Personal Accomplishment to be negatively associated -.31 and Emotional Exhaustion to be positively correlated .21 to externality.

  20. Relatie interne en externe audit

    OpenAIRE

    Ghys, Emelie

    2011-01-01

    In het eerste hoofdstuk wordt de probleemstelling van deze eindverhandeling besproken. Interne en externe audit worden de laatste jaren internationaal en nationaal meer en meer erkend in het bedrijfsleven. Aanleiding voor de toenemende belangstelling van de interne en externe auditfunctie zijn de verschillende boekhoudschandalen rond corporate governance of deugdelijk bestuur. Deze financiële mislukkingen leidden wereldwijd tot diverse wetten, nieuwe regels en verbeterde standaarden om zo een...

  1. Performance Targets and External Benchmarking

    DEFF Research Database (Denmark)

    Friis, Ivar; Hansen, Allan; Vámosi, Tamás S.

    as a market mechanism that can be brought inside the firm to provide incentives for continuous improvement and the development of competitive advances. However, whereas extant research primarily has focused on the importance and effects of using external benchmarks, less attention has been directed towards...... towards the conditions for the use of the external benchmarks we provide more insights to some of the issues and challenges that are related to using this mechanism for performance management and advance competitiveness in organizations....

  2. Parallel External Memory Graph Algorithms

    DEFF Research Database (Denmark)

    Arge, Lars Allan; Goodrich, Michael T.; Sitchinava, Nodari

    2010-01-01

    In this paper, we study parallel I/O efficient graph algorithms in the Parallel External Memory (PEM) model, one o f the private-cache chip multiprocessor (CMP) models. We study the fundamental problem of list ranking which leads to efficient solutions to problems on trees, such as computing lowest...... an optimal speedup of ¿(P) in parallel I/O complexity and parallel computation time, compared to the single-processor external memory counterparts....

  3. Deep 6-DOF Tracking.

    Science.gov (United States)

    Garon, Mathieu; Lalonde, Jean-Francois

    2017-08-10

    We present a temporal 6-DOF tracking method which leverages deep learning to achieve state-of-the-art performance on challenging datasets of real world capture. Our method is both more accurate and more robust to occlusions than the existing best performing approaches while maintaining real-time performance. To assess its efficacy, we evaluate our approach on several challenging RGBD sequences of real objects in a variety of conditions. Notably, we systematically evaluate robustness to occlusions through a series of sequences where the object to be tracked is increasingly occluded. Finally, our approach is purely data-driven and does not require any hand-designed features: robust tracking is automatically learned from data.

  4. EYE GAZE TRACKING

    DEFF Research Database (Denmark)

    2017-01-01

    This invention relates to a method of performing eye gaze tracking of at least one eye of a user, by determining the position of the center of the eye, said method comprising the steps of: detecting the position of at least three reflections on said eye, transforming said positions to spanning...... a normalized coordinate system spanning a frame of reference, wherein said transformation is performed based on a bilinear transformation or a non linear transformation e.g. a möbius transformation or a homographic transformation, detecting the position of said center of the eye relative to the position...... of said reflections and transforming this position to said normalized coordinate system, tracking the eye gaze by tracking the movement of said eye in said normalized coordinate system. Thereby calibration of a camera, such as knowledge of the exact position and zoom level of the camera, is avoided...

  5. Negotiating Family Tracking

    DEFF Research Database (Denmark)

    Sonne Damkjær, Maja; Albrechtslund, Anders; Bøge, Ask Risom

    This presentation explores the question: What motivates the use of tracking technologies in families, and how does the use transform the relations between parent and child? The purpose is to investigate why tracking technologies are used in families and how these technologies potentially change...... the relation between parents and children. The use of tracking technologies in families implicate negotiations about the boundaries of trust and intimacy in parent-child relations which can lead to strategies of resistance or modification (Fotel and Thomsen, 2004; Rooney, 2010; Steeves and Jones, 2010......). In the presentation, we report from a qualitative study that focuses on intergenerational relations. The study draws on empirical data from workshops with Danish families as well as individual and group interviews. We aim to gain insights about the sharing habits and negotiations in intimate family relations...

  6. Tracking of deformable objects

    Science.gov (United States)

    Aswani, Parimal; Wong, K. K.; Chong, Man N.

    2000-12-01

    Tracking of moving-objects in image sequences is needed for several video processing applications such as content-based coding, object oriented compression, object recognition and more recently for video object plane extraction in MPEG-4 coding. Tracking is a natural follow-up of motion-based segmentation. It is a fast and efficient method to achieve coherent motion segments along the temporal axis. Segmenting out moving objects for each and every frame in a video sequence is a computationally expensive approach. Thus, for better performance, semi-automatic segmentation is an acceptable compromise as automatic segmentation approaches rely heavily on prior assumptions. In semi-automatic segmentation approaches, motion-segmentation is performed only on the initial frame and the moving object is tracked in subsequent frames using tracking algorithms. In this paper, a new model for object tracking is proposed, where the image features -- edges, intensity pattern, object motion and initial keyed-in contour (by the user) form the prior and likelihood model of a Markov Random Field (MRF) model. Iterated Conditional Mode (ICM) is used for the minimization of the global energy for the MRF model. The motion segment for each frame is initialized using the segment information from the previous frame. For the initial frame, the motion segment is obtained by manually keying in the object contour. The motion-segments obtained using the proposed model are coherent and accurate. Experimental results on tracking using the proposed algorithm for different sequences -- Bream, Alexis and Claire are presented in this paper. The results obtained are accurate and can be used for a variety of applications including MPEG-4 Video Object Plane (VOP) extraction.

  7. Tracking Your Development

    CERN Document Server

    Hennum, Kelly M

    2011-01-01

    This book provides you with the means to set development goals and to track your progress on achieving them. It can help you efficiently gather and make sense of information about your progress and avoid common pitfalls that can block your development. Tracking your development can be captures in a few steps: articulating your goal, creating an action plan, gathering information about your behavior, indentifying barriers and support, and revising your action plan. Taking these steps will greatly increase the likelihood of achieving your goals.

  8. External Costs Related to Power Production Technologies

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1997-01-01

    The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective...

  9. External Costs Related to Power Production Technologies

    DEFF Research Database (Denmark)

    Ibsen, Liselotte Schleisner; Nielsen, Per Sieverts

    1997-01-01

    The European Commission has launched a major study project, ExternE, to develop a methodology to quantify externalities. A “National Implementation Phase”, was started under the Joule II programme with the purpose of implementing the ExternE methodology in all member states. The main objective of...

  10. Track Reconstruction Performance in CMS

    CERN Document Server

    Azzurri, Paolo

    2008-01-01

    The expected performance of track reconstruction with LHC events using the CMS silicon tracker is presented. Track finding and fitting is accomplished with Kalman Filter techniques that achieve efficiencies above 99\\% on single muons with $p_T >$1~GeV/c. Difficulties arise in the context of standard LHC events with a high density of charged particles, where the rate of fake combinatorial tracks is very large for low $p_T$ tracks, and nuclear interactions in the tracker material reduce the tracking efficiency for charged hadrons. Recent improvements with the CMS track reconstruction now allow to efficiently reconstruct charged tracks with $p_T$ down to few hundred MeV/c and as few as three crossed layers, with a very small fake fraction, by making use of an optimal rejection of fake tracks in conjunction with an iterative tracking procedure.

  11. Tracking whole hand kinematics using extended Kalman filter.

    Science.gov (United States)

    Fu, Qiushi; Santello, Marco

    2010-01-01

    This paper describes the general procedure, model construction, and experimental results of tracking whole hand kinematics using extended Kalman filter (EKF) based on data recorded from active surface markers. We used a hand model with 29 degrees of freedom that consists of hand global posture, wrist, and digits. The marker protocol had 4 markers on the distal forearm and 20 markers on the dorsal surface of the joints of the digits. To reduce computational load, we divided the state space into four sub-spaces, each of which were estimated with an EKF in a specific order. We tested our framework and found reasonably accurate results (2-4 mm tip position error) when sampling tip to tip pinch at 120 Hz.

  12. Attitude tracking control for spacecraft formation with time-varying delays and switching topology

    Science.gov (United States)

    Yang, Hongjiu; You, Xiu; Hua, Changchun

    2016-09-01

    This paper investigates attitude dynamic tracking control for spacecraft formation in the presence of unmeasurable velocity information with time-varying delays and switching topology. Based on an extended state observer, a nonlinear attitude tracking control approach is developed for spacecraft attitude model formulated by Euler-Lagrangian equations. The attitude tracking controller allows for external disturbances and absence of angular velocity information. Both auto-stable region techniques and a Lyapunov function approach are developed to prove ultimately bounded tracking. Simulation results demonstrate effectiveness of the nonlinear control techniques proposed in this paper.

  13. Tracking Speech Sound Acquisition

    Science.gov (United States)

    Powell, Thomas W.

    2011-01-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. "Journal of Speech and Hearing Research", 33, 28-37), uses a railway idiom to track gains in…

  14. Tracking Politics with POWER

    Science.gov (United States)

    Moreira, Silvio; Batista, David S.; Carvalho, Paula; Couto, Francisco M.; Silva, Mario J.

    2013-01-01

    Purpose: POWER is an ontology of political processes and entities. It is designed for tracking politicians, political organizations and elections, both in mainstream and social media. The aim of this paper is to propose a data model to describe political agents and their relations over time. Design/methodology/approach: The authors propose a data…

  15. Fast Passenger Tracks Network

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    China’s fast passenger tracks network consists of four parts:express rail- way with speeds between 300km/h and 350 kin/h,passenger rail lines with speeds between 200 km/h and 250 km/h,intercity high-speed railways that run

  16. Pseudonoise code tracking loop

    Science.gov (United States)

    Laflame, D. T. (Inventor)

    1980-01-01

    A delay-locked loop is presented for tracking a pseudonoise (PN) reference code in an incoming communication signal. The loop is less sensitive to gain imbalances, which can otherwise introduce timing errors in the PN reference code formed by the loop.

  17. Energy Tracking Diagrams

    Science.gov (United States)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-01-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the "Next Generation Science Standards," the primary conceptual learning goal is for learners to conserve energy as they "track" the transfers and transformations of energy within, into, or out of the system of…

  18. Tracking Speech Sound Acquisition

    Science.gov (United States)

    Powell, Thomas W.

    2011-01-01

    This article describes a procedure to aid in the clinical appraisal of child speech. The approach, based on the work by Dinnsen, Chin, Elbert, and Powell (1990; Some constraints on functionally disordered phonologies: Phonetic inventories and phonotactics. "Journal of Speech and Hearing Research", 33, 28-37), uses a railway idiom to track gains in…

  19. Attitude and position tracking

    CSIR Research Space (South Africa)

    Candy, LP

    2011-01-01

    Full Text Available velocity data separately in a suitable frame. In this chapter we make the case for using bivectors as the attitude tracking method of choice since several features make their performance and flexibility superior to that of DCMs, Euler angles or even rotors...

  20. Tracking Self into Place

    Science.gov (United States)

    Piersol, Laura

    2010-01-01

    In an effort to figure out what it means to educate "ecologically," I decided to track down some of the stories that I was living, telling and making as an educator. I ended up lost in the house of environmental education, stuck within the rooms of ecological science and political advocacy. Outside on the lawn sat the story of place based…

  1. Foinaven fast track flowlines

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, L.H.; Mair, J.

    1996-12-31

    The decision by British Petroleum to develop offshore fields west of the Shetlands in water depths exceeding 500 meters within three and a half years of discovery posed a unique submarine pipeline installation challenge. This paper summarizes the salient features of a fast track program to install a diverless subsea pipeline system using rigid reeled pipe technology in an offshore frontier area.

  2. Eye tracking social preferences

    NARCIS (Netherlands)

    Jiang, Ting; Potters, Jan; Funaki, Yukihiko

    We hypothesize that if people are motivated by a particular social preference, then choosing in accordance with this preference will lead to an identifiable pattern of eye movements. We track eye movements while subjects make choices in simple three-person distribution experiments. We characterize

  3. Apple Shuns Tracking Tool

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Apple Inc. is advising software de- velopers to stop using a feature in software for its iPhones and iPads .that has been linked to privacyconcerns, a move that would also take away a widely used tool for tracking users and their behavior. Developers who write programs for Apple's lOS operating system have been using a unique.

  4. The Swift Turbidity Marker

    Science.gov (United States)

    Omar, Ahmad Fairuz; MatJafri, Mohd Zubir

    2011-01-01

    The Swift Turbidity Marker is an optical instrument developed to measure the level of water turbidity. The components and configuration selected for the system are based on common turbidity meter design concepts but use a simplified methodology to produce rapid turbidity measurements. This work is aimed at high school physics students and is the…

  5. Magik Markers Trehvis

    Index Scriptorium Estoniae

    2008-01-01

    Müra-rock'i viljelevast USA duost Magik Markers (ansambel osaleb režissöör Veiko Õunapuu uue mängufilmi "Püha Tõnu kiusamine" võtetel, kontsert 15. nov. Tartus klubis Trehv, vt. www.magikmarkers.audiosport.org.)

  6. Magik Markers Trehvis

    Index Scriptorium Estoniae

    2008-01-01

    Müra-rock'i viljelevast USA duost Magik Markers (ansambel osaleb režissöör Veiko Õunapuu uue mängufilmi "Püha Tõnu kiusamine" võtetel, kontsert 15. nov. Tartus klubis Trehv, vt. www.magikmarkers.audiosport.org.)

  7. Retinal Image-Based Eye-Tracking Using the Tracking Scanning Laser Ophthalmoscope

    Science.gov (United States)

    Sheehy, Christy Kathleen

    The tracking scanning laser ophthalmoscope (TSLO) was designed, built and characterized for high-resolution eye-tracking, imaging, and targeted retinal stimulus delivery. Eye-tracking is done via an image-based software program that monitors the image of the retina over time while simultaneously logging the displacements of the eye. Currently, this system is the most accurate, fast and functional eye-tracking system used in a standard ophthalmic instrument. The TSLO has the ability to non-invasively track the eye at 960 Hz (with an accuracy of 0.2 arcminutes or roughly 1 micron) and present stimuli to the retina at the resolution of single cone photoreceptors (0.66 arcminutes, which is roughly 3 microns). The combination of structural imaging and functional testing allows one to begin to more thoroughly understand retinal disease progression, as well probe specific retinal locations in order to test new treatment efficacies. This level of accuracy is unprecedented in the clinic and is crucial when monitoring minute changes in eye motion, structure, and function. Additionally, the system is capable of providing external eye-tracking for other high-resolution imaging systems, such as optical coherence tomography (OCT) and adaptive optics scanning laser ophthalmoscope (AOSLO) systems through the active steering of an imaging beam. This feature allows the imaging raster or stimuli to stay on target during fixational eye motion. This dissertation steps through all of the above-mentioned uses of the TSLO and further elaborates on the optimal design and system test performance capabilities of the system.

  8. GPS Metric Tracking Unit

    Science.gov (United States)

    2008-01-01

    As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.

  9. Dynamic Active Contours for Visual Tracking.

    Science.gov (United States)

    Niethammer, Marc; Tannenbaum, Allen; Angenent, Sigurd

    2006-01-01

    Visual tracking using active contours is usually set in a static framework. The active contour tracks the object of interest in a given frame of an image sequence. A subsequent prediction step ensures good initial placement for the next frame. This approach is unnatural; the curve evolution gets decoupled from the actual dynamics of the objects to be tracked. True dynamical approaches exist, all being marker particle based and thus prone to the shortcomings of such particle-based implementations. In particular, topological changes are not handled naturally in this framework. The now classical level set approach is tailored for evolutions of manifolds of codimension one. However, dynamic curve evolution is at least a codimension two problem. We propose an efficient, level set based approach for dynamic curve evolution, which addresses the artificial separation of segmentation and prediction while retaining all the desirable properties of the level set formulation. It is based on a new energy minimization functional which, for the first time, puts dynamics into the geodesic active contour framework.

  10. Thermodynamic cost of external control

    Science.gov (United States)

    Barato, Andre C.; Seifert, Udo

    2017-07-01

    Artificial molecular machines are often driven by the periodic variation of an external parameter. This external control exerts work on the system of which a part can be extracted as output if the system runs against an applied load. Usually, the thermodynamic cost of the process that generates the external control is ignored. Here, we derive a refined second law for such small machines that include this cost, which is, for example, generated by free energy consumption of a chemical reaction that modifies the energy landscape for such a machine. In the limit of irreversible control, this refined second law becomes the standard one. Beyond this ideal limiting case, our analysis shows that due to a new entropic term unexpected regimes can occur: the control work can be smaller than the extracted work and the work required to generate the control can be smaller than this control work. Our general inequalities are illustrated by a paradigmatic three-state system.

  11. Leveraging External Sources of Innovation

    DEFF Research Database (Denmark)

    West, Joel; Bogers, Marcel

    2014-01-01

    This paper reviews research on open innovation that considers how and why firms commercialize external sources of innovations. It examines both the “outside-in” and “coupled” modes of open innovation. From an analysis of prior research on how firms leverage external sources of innovation...... cited work beyond those journals. A review of 291 open innovation-related publications from these sources shows that the majority of these articles indeed address elements of this inbound open innovation process model. Specifically, it finds that researchers have front-loaded their examination...... external innovations create value rather than how firms capture value from those innovations. Finally, the interaction phase considers both feedback for the linear process and reciprocal innovation processes such as cocreation, network collaboration, and community innovation. This review and synthesis...

  12. External iliac artery injury secondary to indirect pressure wave effect from gunshot wound

    OpenAIRE

    Ng, Eugene; Choong, Andrew MTL

    2016-01-01

    In patients presenting with gunshot wounds, a high clinical suspicion of injury to vasculature and viscera remote from the projectile track is paramount. We present a case of a 17 year old male who sustained a gunshot wound to his abdomen and subsequently developed a right external iliac artery contusion requiring surgery as an indirect effect of the pressure wave from the bullet.

  13. Externalizing behavior problems and cigarette smoking as predictors of cannabis use : the TRAILS Study

    NARCIS (Netherlands)

    Korhonen, T.; van Leeuwen, A.P.; Reijneveld, S.A.; Ormel, J.; Verhulst, F.C.; Huizink, A.C.

    Objective: To examine externalizing behavior problems and cigarette smoking as predictors Of Subsequent cannabis use. Method: Dutch adolescents (N = 1,606; 854 girls and 752 boys) from the TRacking Adolescents' Individual Lives Survey (TRAILS) ongoing longitudinal study were examined at baseline

  14. Externalizing Behavior Problems and Cigarette Smoking as Predictors of Cannabis Use: The TRAILS Study

    Science.gov (United States)

    Korhonen, Tellervo; van Leeuwen, Andrea Prince; Reijneveld, Sijmen A.; Ormel, Johan; Verhulst, Frank C.; Huizink, Anja C.

    2010-01-01

    Objective: To examine externalizing behavior problems and cigarette smoking as predictors of subsequent cannabis use. Method: Dutch adolescents (N = 1,606; 854 girls and 752 boys) from the TRacking Adolescents' Individual Lives Survey (TRAILS) ongoing longitudinal study were examined at baseline (ages 10-12 [T1]) and at two follow-up assessments…

  15. Externalizing behavior problems and cigarette smoking as predictors of cannabis use : the TRAILS Study

    NARCIS (Netherlands)

    Korhonen, T.; van Leeuwen, A.P.; Reijneveld, S.A.; Ormel, J.; Verhulst, F.C.; Huizink, A.C.

    2010-01-01

    Objective: To examine externalizing behavior problems and cigarette smoking as predictors Of Subsequent cannabis use. Method: Dutch adolescents (N = 1,606; 854 girls and 752 boys) from the TRacking Adolescents' Individual Lives Survey (TRAILS) ongoing longitudinal study were examined at baseline (ag

  16. Externalizing Behavior Problems and Cigarette Smoking as Predictors of Cannabis Use: The TRAILS Study

    Science.gov (United States)

    Korhonen, Tellervo; van Leeuwen, Andrea Prince; Reijneveld, Sijmen A.; Ormel, Johan; Verhulst, Frank C.; Huizink, Anja C.

    2010-01-01

    Objective: To examine externalizing behavior problems and cigarette smoking as predictors of subsequent cannabis use. Method: Dutch adolescents (N = 1,606; 854 girls and 752 boys) from the TRacking Adolescents' Individual Lives Survey (TRAILS) ongoing longitudinal study were examined at baseline (ages 10-12 [T1]) and at two follow-up assessments…

  17. Quality Assurance Training Tracking (QATTS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This is metadata documentation for the Quality Assurance Training Tracking System (QATTS) which tracks Quality Assurace training given by R7 QA staff to in-house...

  18. Thermal Tracking of Sports Players

    DEFF Research Database (Denmark)

    Gade, Rikke; Moeslund, Thomas B.

    2014-01-01

    We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline...... approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels....

  19. Robust object tracking techniques for vision-based 3D motion analysis applications

    Science.gov (United States)

    Knyaz, Vladimir A.; Zheltov, Sergey Y.; Vishnyakov, Boris V.

    2016-04-01

    Automated and accurate spatial motion capturing of an object is necessary for a wide variety of applications including industry and science, virtual reality and movie, medicine and sports. For the most part of applications a reliability and an accuracy of the data obtained as well as convenience for a user are the main characteristics defining the quality of the motion capture system. Among the existing systems for 3D data acquisition, based on different physical principles (accelerometry, magnetometry, time-of-flight, vision-based), optical motion capture systems have a set of advantages such as high speed of acquisition, potential for high accuracy and automation based on advanced image processing algorithms. For vision-based motion capture accurate and robust object features detecting and tracking through the video sequence are the key elements along with a level of automation of capturing process. So for providing high accuracy of obtained spatial data the developed vision-based motion capture system "Mosca" is based on photogrammetric principles of 3D measurements and supports high speed image acquisition in synchronized mode. It includes from 2 to 4 technical vision cameras for capturing video sequences of object motion. The original camera calibration and external orientation procedures provide the basis for high accuracy of 3D measurements. A set of algorithms as for detecting, identifying and tracking of similar targets, so for marker-less object motion capture is developed and tested. The results of algorithms' evaluation show high robustness and high reliability for various motion analysis tasks in technical and biomechanics applications.

  20. Track Initiation for Electro-Optical Tracking of Space Objects

    Science.gov (United States)

    Xu, Z. W.; Wang, X.

    2016-03-01

    Aimed at the track initiation for the electro-optical tracking of space objects, and based on modified Hough transformation, a track initiation algorithm without prior information is proposed to realize the fully robotic identification and tracking of moving objects. The method is valid for the tracking of multi-target as well as with a non-continuous sequence. Simulation shows that the method is effective and applicable for operational usage, and is especially good for the search and discovery of new objects.

  1. STR MARKERS. GENOTYPING APPLICATIONS

    Directory of Open Access Journals (Sweden)

    I. O. Sirbu

    2001-01-01

    Full Text Available STR (short tandem repeats loci consist of short, repetitive sequence elements of 2-8 bp in length. These abundant repeats are well distributed throughout the human genome and are rich source of highly polymorphic markers. There are literally hundreds of STR systems which have been mapped throughout the human genome. Several dozen have been investigated for application to human identity testing. These STR loci are found on almost every chromosome in the genome. They may be amplified using a variety of PCR primers. Tetranucleotide repeats have been most popular among forensic scientists due to their fidelity in PCR amplification although some tri- and pentanucleotide repeats are also in use. In this paper we intend (far from being exhaustive to present a synthesis of the characteristics of these genetic markers and their applications in genotyping, giving as an example the use of the STRs in a paternity testing case.

  2. The urine marker test

    DEFF Research Database (Denmark)

    Elbe, Anne-Marie; Jensen, Stine Nylandsted; Elsborg, Peter

    2016-01-01

    BACKGROUND: Urine sample collection for doping control tests is a key component of the World Anti-Doping Agency's fight against doping in sport. However, a substantial number of athletes experience difficulty when having to urinate under supervision. Furthermore, it cannot always be ensured...... that athletes are actually delivering their own urine. A method that can be used to alleviate the negative impact of a supervised urination procedure and which can also identify urine as coming from a specific athlete is the urine marker test. Monodisperse low molecular weight polyethylene glycols (PEGs......) are given orally prior to urination. Urine samples can be traced to the donor by analysis of the PEGs previously given. OBJECTIVE: The objective of this study was to investigate the use of the urine marker during urine doping control testing. METHODS: Two studies investigated athletes' acceptance...

  3. Fluid markers of traumatic brain injury.

    Science.gov (United States)

    Zetterberg, Henrik; Blennow, Kaj

    2015-05-01

    Traumatic brain injury (TBI) occurs when an external force traumatically injures the brain. Whereas severe TBI can be diagnosed using a combination of clinical signs and standard neuroimaging techniques, mild TBI (also called concussion) is more difficult to detect. This is where fluid markers of injury to different cell types and subcellular compartments in the central nervous system come into play. These markers are often proteins, peptides or other molecules with selective or high expression in the brain, which can be measured in the cerebrospinal fluid or blood as they leak out or get secreted in response to the injury. Here, we review the literature on fluid markers of neuronal, axonal and astroglial injury to diagnose mild TBI and to predict clinical outcome in patients with head trauma. We also discuss chronic traumatic encephalopathy, a progressive neurodegenerative disease in individuals with a history of multiple mild TBIs in a biomarker context. This article is part of a Special Issue entitled 'Traumatic Brain Injury'. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. The track nanotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Waheed, A. [British Institute of Technology and E-Commerce, London E7 9HZ (United Kingdom); Physics Department, University of Reading, Reading RG6 6AF (United Kingdom); Forsyth, D., E-mail: dforsyth@bite.ac.u [British Institute of Technology and E-Commerce, London E7 9HZ (United Kingdom); Watts, A. [Department of Physics, UCL, London Centre of Nanotechnology (LCN), 17-19 Gordon Street, London WC1H OAH (United Kingdom); Saad, A.F. [Physics Department, Faculty of Science, Garyounis University, Benghazi (Libyan Arab Jamahiriya); Mitchell, G.R. [British Institute of Technology and E-Commerce, London E7 9HZ (United Kingdom); Physics Department, University of Reading, Reading RG6 6AF (United Kingdom); Farmer, M. [British Institute of Technology and E-Commerce, London E7 9HZ (United Kingdom); Harris, P.J.F. [Physics Department, University of Reading, Reading RG6 6AF (United Kingdom)

    2009-10-15

    The discipline now called Solid State Nuclear Track Detection (SSNTD) dates back to 1958 and has its roots in the United Kingdom. Its strength stems chiefly from factors such as its simplicity, small geometry, permanent maintenance of the nuclear record and other diversified applications. A very important field with exciting applications reported recently in conjuction with the nuclear track technique is nanotechnology, which has applications in biology, chemistry, industry, medicare and health, information technology, biotechnology, and metallurgical and chemical technologies. Nanotechnology requires material design followed by the study of the quantum effects for final produced applications in sensors, medical diagnosis, information technology to name a few. We, in this article, present a review of past and present applications of SSNTD suggesting ways to apply the technique in nanotechnology, with special reference to development of nanostructure for applications utilising nanowires, nanofilters and sensors.

  5. Tracking change over time

    Science.gov (United States)

    ,

    2011-01-01

    Landsat satellites capture images of Earth from space-and have since 1972! These images provide a long-term record of natural and human-induced changes on the global landscape. Comparing images from multiple years reveals slow and subtle changes as well as rapid and devastating ones. Landsat images are available over the Internet at no charge. Using the free software MultiSpec, students can track changes to the landscape over time-just like remote sensing scientists do! The objective of the Tracking Change Over Time lesson plan is to get students excited about studying the changing Earth. Intended for students in grades 5-8, the lesson plan is flexible and may be used as a student self-guided tutorial or as a teacher-led class lesson. Enhance students' learning of geography, map reading, earth science, and problem solving by seeing landscape changes from space.

  6. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    and many experiments are only becoming possible with the current development of tracking technologies. During this thesis work I have been tracking the poorly known movements of several species of long-distance migrants and document highly complex migration patterns. In three manuscripts these movements......Migratory movements of birds has always fascinated man and led to many questions concerning the ecological drivers behind, the necessary adaptations and the navigational abilities required. However, especially for the long-distance migrants, basic descriptions of their movements are still lacking...... habitats with those in rural habitats. Some species have decreased the frequency of migrants and migration distance in urban environments, and others have not. The other manuscript describes the small scale movements of three different Palaearctic migrants during winter in Africa in a farmland habitat...

  7. Structural Sparse Tracking

    KAUST Repository

    Zhang, Tianzhu

    2015-06-01

    Sparse representation has been applied to visual tracking by finding the best target candidate with minimal reconstruction error by use of target templates. However, most sparse representation based trackers only consider holistic or local representations and do not make full use of the intrinsic structure among and inside target candidates, thereby making the representation less effective when similar objects appear or under occlusion. In this paper, we propose a novel Structural Sparse Tracking (SST) algorithm, which not only exploits the intrinsic relationship among target candidates and their local patches to learn their sparse representations jointly, but also preserves the spatial layout structure among the local patches inside each target candidate. We show that our SST algorithm accommodates most existing sparse trackers with the respective merits. Both qualitative and quantitative evaluations on challenging benchmark image sequences demonstrate that the proposed SST algorithm performs favorably against several state-of-the-art methods.

  8. Lipoprotein marker for hypertriglyceridemia

    Energy Technology Data Exchange (ETDEWEB)

    Cubicciotti, Roger S. (El Cerrito, CA); Karu, Alexander E. (Kensington, CA); Krauss, Ronald M. (Berkeley, CA)

    1986-01-01

    Methods and compositions are provided for the detection of a particular low density lipoprotein which has been found to be a marker for patients suffering from type IV hypertriglyceridemia. A monoclonal antibody capable of specifically binding to a characteristic epitopic site on this LDL subspecies can be utilized in a wide variety of immunoassays. Hybridoma cell line SPL.IVA5A1 was deposited at the American Type Culture Collection on Mar. 29, 1984, and granted accession no. HB 8535.

  9. Alcoholism: Current Marker Research

    Science.gov (United States)

    1984-03-01

    mongolism are high-risk candidates for certain types of leukemia. Similarly, hemophiliacs have a correspondingly high incidence of color blindness . (4...genetically determined characteristics such as color blindness and blood type. GENETIC MARKER STUDIES In 1966 Dr. Cruz-Coke and Dr. Varela reported that...their study had linked color blindness , cirrhosis of the liver and alcoholism. They further hypothesized the existence of a sex-linked carrier gene

  10. Issues in Target Tracking

    Science.gov (United States)

    2010-05-01

    the CUSUM (Page) test yields the quickest detection of a change of distribution for the case of i.i.d. observations [3]. In fact, in a (highly...11. Autocorrelation of the CUSUM increments, sn, under H1 (target present). Issues in Target Tracking RTO-EN-SET-157(2010...restrictive condition that the increments of the cumulative sum, sn, be i.i.d. [3], [22]. Fig. 11 plots the autocorrelation of the CUSUM increments as a

  11. Tracking Online Trails

    Science.gov (United States)

    Qi, Man; Edgar-Nevill, Denis; Wang, Yongquan; Xu, Rongsheng

    Traceability is a key to the investigation of the internet criminal and a cornerstone of internet research. It is impossible to prevent all internet misuse but may be possible to identify and trace the users, and then take appropriate action. This paper presents the value of traceability within the email/-newsposting utilities, the technologies being using to hide identities, the difficulties in locating the traceable data and the challenges in tracking online trails.

  12. Tracking theories of knowledge

    Directory of Open Access Journals (Sweden)

    Adams, Fred

    2005-01-01

    Full Text Available As teorias epistemológicas do rastreamento sustentam que o conhecimento é uma relação real entre o agente cognitivo e seu ambiente. Os estados cognitivos de um agente epistêmico fazem o rastreamento da verdade das proposições que são objeto de conhecimento ao embasarem a crença em indicadores confiáveis da verdade (evidência, razões, ou métodos de formação de crença. A novidade nessa abordagem é que se dá pouca ênfase no tipo de justificação epistêmica voltada ao fornecimento de procedimentos de decisão doxástica ou regras de responsabilidade epistêmica. Este artigo oferece um pouco da história das teorias de rastreamento e, então, defende-as contra muitas objeções que se pretendem (equivocadamente refutadoras dessas teorias. Tracking theories of knowledge maintain that knowledge is a real relation between cognitive agent and environment. Cognitive states of a knower track the truth of known propositions by basing belief on reliable indicators of truth (evidence, reasons, or belief forming methods. The novelty of this approach is that it places little emphasis on epistemic justification of a kind that aims at guiding epistemic agents by giving doxastic decision procedures or rules of epistemic responsibility. This paper gives some of the history of tracking theories, and then defends them against many of the objections most often judged (mistakenly to refute tracking theories.

  13. Registration and Tracking Report

    Science.gov (United States)

    2006-02-01

    the layer ownership probabilities are maximized. Isard and MacCormick [71] propose joint modelling of the background and foreground regions for...gradients. Isard et. al [71] define the object state in terms of spline shape parameters and affine motion parameters. The measurements consist of image...Conference on Automatic Face and Gesture Recognition May 17 - 19, 2004 Seoul, Korea 86 [7] Michael Isard , Andrew Blake, ”Condensation Tracking By

  14. BESⅢ track fitting algorithm

    Institute of Scientific and Technical Information of China (English)

    WANG Ji-Ke; MAO Ze-Pu; BIAN Jian-Ming; CAO Guo-Fu; CAO Xue-Xiang; CHEN Shen-Jian; DENG Zi-Yan; FU Cheng-Dong; GAO Yuan-Ning; HE Kang-Lin; HE Miao; HUA Chun-Fei; HUANG Bin; HUANG Xing-Tao; JI Xiao-Sin; LI Fei; LI Hai-Bo; LI Wei-Dong; LIANG Yu-Tie; LIU Chun-Xiu; LIU Huai-Min; LIU Suo; LIU Ying-Jie; MA Qiu-Mei; MA Xiang; MAO Ya-Jun; MO Xiao-Hu; PAN Ming-Hua; PANG Cai-Ying; PING Rong-Gang; QIN Ya-Hong; QIU Jin-Fa; SUN Sheng-Sen; SUN Yong-Zhao; WANG Liang-Liang; WEN Shuo-Pin; WU Ling-Hui; XIE Yu-Guang; XU Min; YAN Liang; YOU Zheng-Yun; YUAN Chang-Zheng; YUAN Ye; ZHANG Bing-Yun; ZHANG Chang-Chun; ZHANG Jian-Yong; ZHANG Xue-Yao; ZHANG Yao; ZHENG Yang-Heng; ZHU Ke-Jun; ZHU Yong-Sheng; ZHU Zhi-Li; ZOU Jia-Heng

    2009-01-01

    A track fitting algorithm based on the Kalman filter method has been developed for BESⅢ of BEPCⅡ.The effects of multiple scattering and energy loss when the charged particles go through the detector,non-uniformity of magnetic field (NUMF) and wire sag, etc., have been carefully handled.This algorithm works well and the performance satisfies the physical requirements tested by the simulation data.

  15. Optimal Auctions with Financial Externalities

    NARCIS (Netherlands)

    Maasland, E.; Onderstal, A.M.

    2002-01-01

    We construct optimal auctions when bidders face financial externalities.In a Coasean World, in which the seller cannot prevent a perfect resale market, nor withhold the object, the lowest-price all-pay auction is optimal.In a Myersonean World, in which the seller can both prevent resale after the au

  16. Organizing for External Knowledge Sourcing

    DEFF Research Database (Denmark)

    Rabbiosi, Larissa; Reichstein, Toke

    2011-01-01

    The aim of this article is to provide an introduction to the special issue. We briefly consider the external knowledge sourcing and organizing for innovation literatures, which offer a background for the special issue, and we highlight their mutual dialogue. We then illustrate the main findings...

  17. Measuring Externalities in Program Evaluation

    NARCIS (Netherlands)

    Janssens, Wendy

    2005-01-01

    Impact evaluations of development programmes usually focus on a comparison of participants with a control group. However, if the programme generates externalities for non-participants such an approach will capture only part of the programme's impact. Based on a unique large-scale quantitative survey

  18. Lupus vulgaris of external nose.

    Science.gov (United States)

    Bhandary, Satheesh Kumar; Ranganna, B Usha

    2008-12-01

    Lupus vulgaris is the commonest form of cutaneous tuberculosis which commonly involve trunk and buttocks. Lupus vulgaris affecting nose and face, are rarely reported in India. This study reports an unusual case of lupus vulgaris involving the external nose that showed dramatic outcome after six months of anti- tubercular treatment.

  19. [Treatment by external insulin pump].

    Science.gov (United States)

    Clavel, Sylvaine

    2010-12-01

    Since the recent recommendations by the French speaking association for research on diabetes and metabolic illnesses (Alfediam), treatment by insulin pump has found itself in competition with basal-bolus, a procedure using similar injections of insulin which has become a benchmark treatment. The latest Alfediam guidelines focus on defining ways of treating diabetics with an external insulin pump.

  20. Matchings with Externalities and Attitudes

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal;

    2013-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas ...

  1. Post-external dacryocystorhinostomy lagophthalmos.

    Science.gov (United States)

    Odat, Thabit A; Odat, Haitham A; Khraisat, Heba; Odat, Mohannad A; Alzoubi, Firas Q

    2015-06-01

    To describe lagophthalmos and eyelid closure abnormality after external dacryocystorhinostomy (DCR). A retrospective review of medical records and postoperative photographs of 79 patients who underwent external DCR for nasolacrimal duct obstruction and developed eyelid closure abnormality and lagophthalmos with or without exposure keratopathy was conducted. Collected data included age, sex, indication for surgery, laterality, length and type of incision, length of follow-up duration, presence of punctate epithelial keratopathy, and time for resolution of eyelid closure abnormalities. Twenty-seven patients with 28 external dacryocystorhinostomy had postoperative eyelid closure abnormalities. Male to female ratio was 1:6. The mean age was 40.1 years (range 9-80 years). All surgeries were performed through diagonal skin incision. Lagophthalmos involving the medial third of the palpebral fissure was noticed in 28.6 % of cases. All patients had hypometric blink mainly of the upper eyelid. One patient had punctate epithelial keratopathy. Resolution of lagophthalmos was noticed over a period of 1-5 weeks with an average of 3 weeks. None of the patients continued to have residual hypometric blink or punctate keratopathy at the last follow-up time. The mean follow-up period was 4.2 months (range 3-6 months). Eyelid closure abnormality and lagophthalmos after external DCR are underestimated problems. Spontaneous resolution is seen in all cases weeks to months after surgery.

  2. Femoral Reconstruction Using External Fixation

    Directory of Open Access Journals (Sweden)

    Yevgeniy Palatnik

    2011-01-01

    Full Text Available Background. The use of an external fixator for the purpose of distraction osteogenesis has been applied to a wide range of orthopedic problems caused by such diverse etiologies as congenital disease, metabolic conditions, infections, traumatic injuries, and congenital short stature. The purpose of this study was to analyze our experience of utilizing this method in patients undergoing a variety of orthopedic procedures of the femur. Methods. We retrospectively reviewed our experience of using external fixation for femoral reconstruction. Three subgroups were defined based on the primary reconstruction goal lengthening, deformity correction, and repair of nonunion/bone defect. Factors such as leg length discrepancy (LLD, limb alignment, and external fixation time and complications were evaluated for the entire group and the 3 subgroups. Results. There was substantial improvement in the overall LLD, femoral length discrepancy, and limb alignment as measured by mechanical axis deviation (MAD and lateral distal femoral angle (LDFA for the entire group as well as the subgroups. Conclusions. The Ilizarov external fixator allows for decreased surgical exposure and preservation of blood supply to bone, avoidance of bone grafting and internal fixation, and simultaneous lengthening and deformity correction, making it a very useful technique for femoral reconstruction.

  3. Neural adaptive attitude tracking controller for flexible spacecraft

    Institute of Scientific and Technical Information of China (English)

    XIAO Bing; HU Qing-lei; MA Guang-fu

    2010-01-01

    In this paper,a neural network adaptive controller is proposed for attitude tracking of flexible spacecraft in presence of unknown inertial matrix and external disturbance.In this approach,neural network technique is employed to approximate the unknown system dynamics with finite combinations of some basis functions,and a robust controller is also designed to attenuate the effect of approximation error,more specially,the knowledge of angular velocity is not required.In the closed-loop system,Lyapunov stability analysis shows that the attitude trajectories asymptotically follow the reference output trajectories.Finally,simulation results are presented for the attitude tracking of a flexible spacecraft to show the excellent performance of the proposed controller and illustrate its robustness in face of external disturbances and unknown dynamics.

  4. A novel accurate minioptical tracking system for percutaneous needle placement.

    Science.gov (United States)

    von Jako, Christopher R; Zuk, Yuval; Zur, Oded; Gilboa, Pini

    2013-08-01

    The novel optical tracking system employs a miniature video camera, mounted on the hub of an interventional needle, to determine the location and orientation of the needle relative to a skin-attached sticker with color reference markers. A computed tomography (CT) scan is used to register the same reference markers to the anatomy in the CT images, and thus, register the needle to the anatomy and to a user-selected target. A computer displays a simulation of the interventional needle on the CT images, providing guidance information to assist a user in directing the needle to the target. Bench testing was performed on a custom phantom to determine the accuracy of this minioptical tracking system. The resulting accuracy data demonstrate a good correlation with phantom coordinates and the CT images.

  5. Energy Tracking Diagrams

    Science.gov (United States)

    Scherr, Rachel E.; Harrer, Benedikt W.; Close, Hunter G.; Daane, Abigail R.; DeWater, Lezlie S.; Robertson, Amy D.; Seeley, Lane; Vokos, Stamatis

    2016-02-01

    Energy is a crosscutting concept in science and features prominently in national science education documents. In the Next Generation Science Standards, the primary conceptual learning goal is for learners to conserve energy as they track the transfers and transformations of energy within, into, or out of the system of interest in complex physical processes. As part of tracking energy transfers among objects, learners should (i) distinguish energy from matter, including recognizing that energy flow does not uniformly align with the movement of matter, and should (ii) identify specific mechanisms by which energy is transferred among objects, such as mechanical work and thermal conduction. As part of tracking energy transformations within objects, learners should (iii) associate specific forms with specific models and indicators (e.g., kinetic energy with speed and/or coordinated motion of molecules, thermal energy with random molecular motion and/or temperature) and (iv) identify specific mechanisms by which energy is converted from one form to another, such as incandescence and metabolism. Eventually, we may hope for learners to be able to optimize systems to maximize some energy transfers and transformations and minimize others, subject to constraints based in both imputed mechanism (e.g., objects must have motion energy in order for gravitational energy to change) and the second law of thermodynamics (e.g., heating is irreversible). We hypothesize that a subsequent goal of energy learning—innovating to meet socially relevant needs—depends crucially on the extent to which these goals have been met.

  6. Mitigating Errors in External Respiratory Surrogate-Based Models of Tumor Position

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, Kathleen T. [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); McAvoy, Thomas J. [Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); Department of Chemical and Biomolecular Engineering and Institute of Systems Research, University of Maryland, College Park, MD (United States); George, Rohini [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Dieterich, Sonja [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); D' Souza, Warren D., E-mail: wdsou001@umaryland.edu [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States)

    2012-04-01

    Purpose: To investigate the effect of tumor site, measurement precision, tumor-surrogate correlation, training data selection, model design, and interpatient and interfraction variations on the accuracy of external marker-based models of tumor position. Methods and Materials: Cyberknife Synchrony system log files comprising synchronously acquired positions of external markers and the tumor from 167 treatment fractions were analyzed. The accuracy of Synchrony, ordinary-least-squares regression, and partial-least-squares regression models for predicting the tumor position from the external markers was evaluated. The quantity and timing of the data used to build the predictive model were varied. The effects of tumor-surrogate correlation and the precision in both the tumor and the external surrogate position measurements were explored by adding noise to the data. Results: The tumor position prediction errors increased during the duration of a fraction. Increasing the training data quantities did not always lead to more accurate models. Adding uncorrelated noise to the external marker-based inputs degraded the tumor-surrogate correlation models by 16% for partial-least-squares and 57% for ordinary-least-squares. External marker and tumor position measurement errors led to tumor position prediction changes 0.3-3.6 times the magnitude of the measurement errors, varying widely with model algorithm. The tumor position prediction errors were significantly associated with the patient index but not with the fraction index or tumor site. Partial-least-squares was as accurate as Synchrony and more accurate than ordinary-least-squares. Conclusions: The accuracy of surrogate-based inferential models of tumor position was affected by all the investigated factors, except for the tumor site and fraction index.

  7. Towards a Stable Robotic Object Manipulation Through 2D-3D Features Tracking

    Directory of Open Access Journals (Sweden)

    Sorin M. Grigorescu

    2013-04-01

    Full Text Available In this paper, a new object tracking system is proposed to improve the object manipulation capabilities of service robots. The goal is to continuously track the state of the visualized environment in order to send visual information in real time to the path planning and decision modules of the robot; that is, to adapt the movement of the robotic system according to the state variations appearing in the imaged scene. The tracking approach is based on a probabilistic collaborative tracking framework developed around a 2D patch‐based tracking system and a 2D‐3D point features tracker. The real‐time visual information is composed of RGB‐D data streams acquired from state‐of‐the‐art structured light sensors. For performance evaluation, the accuracy of the developed tracker is compared to a traditional marker‐based tracking system which delivers 3D information with respect to the position of the marker.

  8. Beta-2 Microglobulin Tumor Marker

    Science.gov (United States)

    ... services. Advertising & Sponsorship: Policy | Opportunities Beta-2 Microglobulin Tumor Marker Share this page: Was this page helpful? Also ... Microglobulin, Serum, Urine, or CSF Related tests: Albumin , Tumor Markers , CSF Analysis All content on Lab Tests Online ...

  9. Fuzzy Logic Particle Tracking

    Science.gov (United States)

    2005-01-01

    A new all-electronic Particle Image Velocimetry technique that can efficiently map high speed gas flows has been developed in-house at the NASA Lewis Research Center. Particle Image Velocimetry is an optical technique for measuring the instantaneous two component velocity field across a planar region of a seeded flow field. A pulsed laser light sheet is used to illuminate the seed particles entrained in the flow field at two instances in time. One or more charged coupled device (CCD) cameras can be used to record the instantaneous positions of particles. Using the time between light sheet pulses and determining either the individual particle displacements or the average displacement of particles over a small subregion of the recorded image enables the calculation of the fluid velocity. Fuzzy logic minimizes the required operator intervention in identifying particles and computing velocity. Using two cameras that have the same view of the illumination plane yields two single exposure image frames. Two competing techniques that yield unambiguous velocity vector direction information have been widely used for reducing the single-exposure, multiple image frame data: (1) cross-correlation and (2) particle tracking. Correlation techniques yield averaged velocity estimates over subregions of the flow, whereas particle tracking techniques give individual particle velocity estimates. For the correlation technique, the correlation peak corresponding to the average displacement of particles across the subregion must be identified. Noise on the images and particle dropout result in misidentification of the true correlation peak. The subsequent velocity vector maps contain spurious vectors where the displacement peaks have been improperly identified. Typically these spurious vectors are replaced by a weighted average of the neighboring vectors, thereby decreasing the independence of the measurements. In this work, fuzzy logic techniques are used to determine the true

  10. Real-Time Bioluminescent Tracking of Cellular Population Dynamics

    OpenAIRE

    Close, Dan; Xu, Tingling; Ripp, Steven; Sayler, Gary

    2014-01-01

    Cellular population dynamics are routinely monitored across many diverse fields for a variety of purposes. In general, these dynamics are assayed either through the direct counting of cellular aliquots followed by extrapolation to the total population size, or through the monitoring of signal intensity from any number of externally stimulated reporter proteins. While both viable methods, here we describe a novel technique that allows for the automated, non-destructive tracking of cellular pop...

  11. Real-Time Bioluminescent Tracking of Cellular Population Dynamics

    OpenAIRE

    Close, Dan; Xu, Tingling; Ripp, Steven; Sayler, Gary

    2014-01-01

    Cellular population dynamics are routinely monitored across many diverse fields for a variety of purposes. In general, these dynamics are assayed either through the direct counting of cellular aliquots followed by extrapolation to the total population size, or through the monitoring of signal intensity from any number of externally stimulated reporter proteins. While both viable methods, here we describe a novel technique that allows for the automated, non-destructive tracking of cellular pop...

  12. Magnitude of Interfractional Vaginal Cuff Movement: Implications for External Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Daniel J. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Michaletz-Lorenz, Martha [Department of Education and Training, Elekta, Maryland Heights, MO (United States); Goddu, S. Murty [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Grigsby, Perry W., E-mail: pgrigsby@wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO (United States); Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO (United States)

    2012-03-15

    Purpose: To quantify the extent of interfractional vaginal cuff movement in patients receiving postoperative irradiation for cervical or endometrial cancer in the absence of bowel/bladder instruction. Methods and Materials: Eleven consecutive patients with cervical or endometrial cancer underwent placement of three gold seed fiducial markers in the vaginal cuff apex as part of standard of care before simulation. Patients subsequently underwent external irradiation and brachytherapy treatment based on institutional guidelines. Daily megavoltage CT imaging was performed during each external radiation treatment fraction. The daily positions of the vaginal apex fiducial markers were subsequently compared with the original position of the fiducial markers on the simulation CT. Composite dose-volume histograms were also created by summing daily target positions. Results: The average ({+-} standard deviation) vaginal cuff movement throughout daily pelvic external radiotherapy when referenced to the simulation position was 16.2 {+-} 8.3 mm. The maximum vaginal cuff movement for any patient during treatment was 34.5 mm. In the axial plane the mean vaginal cuff movement was 12.9 {+-} 6.7 mm. The maximum vaginal cuff axial movement was 30.7 mm. In the craniocaudal axis the mean movement was 10.3 {+-} 7.6 mm, with a maximum movement of 27.0 mm. Probability of cuff excursion outside of the clinical target volume steadily dropped as margin size increased (53%, 26%, 4.2%, and 1.4% for 1.0, 1.5, 2.0, and 2.5 cm, respectively.) However, rectal and bladder doses steadily increased with larger margin sizes. Conclusions: The magnitude of vaginal cuff movement is highly patient specific and can impact target coverage in patients without bowel/bladder instructions at simulation. The use of vaginal cuff fiducials can help identify patients at risk for target volume excursion.

  13. Defensive externality and blame projection following failure.

    Science.gov (United States)

    Hochreich, D J

    1975-09-01

    This study focuses upon the relationship between internal-external control and defensive blame projection. Trust was used as a moderator variable for making differential predictions concerning the behavior of two subgroups of externals: defensive externals, whose externality is presumed to reflect primarily a verbal technique of defense, and congruent externals, whose externality reflects a more genuine belief that most outcomes are determined by forces beyond their personal control. As predicted, defensive externals showed a stronger tendency than did congruent externals and internals to resort to blame projection following failure at an achievement task. There were no group differences in attribution following task success. Defensive externals were found to be more responsive to negative feedback than were congruent externals.

  14. Thermal Tracking of Sports Players

    Directory of Open Access Journals (Sweden)

    Rikke Gade

    2014-07-01

    Full Text Available We present here a real-time tracking algorithm for thermal video from a sports game. Robust detection of people includes routines for handling occlusions and noise before tracking each detected person with a Kalman filter. This online tracking algorithm is compared with a state-of-the-art offline multi-target tracking algorithm. Experiments are performed on a manually annotated 2-minutes video sequence of a real soccer game. The Kalman filter shows a very promising result on this rather challenging sequence with a tracking accuracy above 70% and is superior compared with the offline tracking approach. Furthermore, the combined detection and tracking algorithm runs in real time at 33 fps, even with large image sizes of 1920 × 480 pixels.

  15. When attention wanders: Pupillometric signatures of fluctuations in external attention.

    Science.gov (United States)

    Konishi, Mahiko; Brown, Kevin; Battaglini, Luca; Smallwood, Jonathan

    2017-11-01

    Attention is not always directed to events in the external environment. On occasion our thoughts wander to people and places distant from the here and now. Sometimes, this lack of external attention can compromise ongoing task performance. In the current study we set out to understand the extent to which states of internal and external attention can be determined using pupillometry as an index of ongoing cognition. In two experiments we found that periods of slow responding were associated with elevations in the baseline pupil signal over three and a half seconds prior to a behavioural response. In the second experiment we found that unlike behavioural lapses, states of off-task thought, particularly those associated with a focus on the past and with an intrusive quality, were associated with reductions in the size of the pupil over the same window prior to the probe. These data show that both states of large and small baseline pupil size are linked to states when attention is not effectively focused on the external environment, although these states have different qualities. More generally, these findings illustrate that subjective and objective markers of task performance may not be equivalent and underscore the importance of developing objective indicators that can allow these different states to be understood. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Track Processing Approach for Bearing-Only Target Tracking

    Directory of Open Access Journals (Sweden)

    Hui Chen

    2009-10-01

    Full Text Available This paper mainly studies angle-measurement based track processing approach to overcome the existing problems in the applications of traditional approaches for bearing-only target locating and tracking system. First, this paper gives suited data association algorithms including track initiation and point-track association. Moreover, a new tracking filtering association gate method is presented through analysis of the target motion characteristics in polar coordinates for improving bearing-only measurement confirming efficiency of real target and limiting false track overextension with the dense clutter. Then, by analyzing the feasibility of using multi-model technology, the IMM is adopt as filtering algorithm to solve existing problem in bearing-only tracking for complicated target motion in two dimensional angle plane. As the results, the two dimensional bearing-only tracking accuracy of real target is improved and false tracking is greatly limited. Moreover, computation cost of IMM is analyzed in view of the real-time demand of bearing-only tracking. Finally, this paper gives some concrete summary of multi-model choosing principle. The application of the proposed approach in a simulation system proves its effectiveness and practicability.

  17. A novel open-loop tracking strategy for photovoltaic systems.

    Science.gov (United States)

    Alexandru, Cătălin

    2013-01-01

    This paper approaches a dual-axis equatorial tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. The innovative aspect in the solar tracker design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with the motor torques whose computation is based on the dynamic model of the mechanical structure on which external forces act. The daily and elevation angles of the PV module represent the input parameters in the mechanical device, while the outputs transmitted to the controller are the motor torques. The controller tuning is approached by a parametric optimization process, using design of experiments and response surface methodology techniques, in a multiple regression. The simulation and experimental results demonstrate the operational performance of the tracking system.

  18. A Novel Open-Loop Tracking Strategy for Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Cătălin Alexandru

    2013-01-01

    Full Text Available This paper approaches a dual-axis equatorial tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. The innovative aspect in the solar tracker design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with the motor torques whose computation is based on the dynamic model of the mechanical structure on which external forces act. The daily and elevation angles of the PV module represent the input parameters in the mechanical device, while the outputs transmitted to the controller are the motor torques. The controller tuning is approached by a parametric optimization process, using design of experiments and response surface methodology techniques, in a multiple regression. The simulation and experimental results demonstrate the operational performance of the tracking system.

  19. Close-Range Tracking of Underwater Vehicles Using Light Beacons.

    Science.gov (United States)

    Bosch, Josep; Gracias, Nuno; Ridao, Pere; Istenič, Klemen; Ribas, David

    2016-03-25

    This paper presents a new tracking system for autonomous underwater vehicles (AUVs) navigating in a close formation, based on computer vision and the use of active light markers. While acoustic localization can be very effective from medium to long distances, it is not so advantageous in short distances when the safety of the vehicles requires higher accuracy and update rates. The proposed system allows the estimation of the pose of a target vehicle at short ranges, with high accuracy and execution speed. To extend the field of view, an omnidirectional camera is used. This camera provides a full coverage of the lower hemisphere and enables the concurrent tracking of multiple vehicles in different positions. The system was evaluated in real sea conditions by tracking vehicles in mapping missions, where it demonstrated robust operation during extended periods of time.

  20. Real time markerless motion tracking using linked kinematic chains

    Science.gov (United States)

    Luck, Jason P.; Small, Daniel E.

    2007-08-14

    A markerless method is described for tracking the motion of subjects in a three dimensional environment using a model based on linked kinematic chains. The invention is suitable for tracking robotic, animal or human subjects in real-time using a single computer with inexpensive video equipment, and does not require the use of markers or specialized clothing. A simple model of rigid linked segments is constructed of the subject and tracked using three dimensional volumetric data collected by a multiple camera video imaging system. A physics based method is then used to compute forces to align the model with subsequent volumetric data sets in real-time. The method is able to handle occlusion of segments and accommodates joint limits, velocity constraints, and collision constraints and provides for error recovery. The method further provides for elimination of singularities in Jacobian based calculations, which has been problematic in alternative methods.

  1. Robust and efficient feature tracking for indoor navigation.

    Science.gov (United States)

    Rodrigo, Ranga; Zouqi, Mehrnaz; Chen, Zhenhe; Samarabandu, Jagath

    2009-06-01

    Robust feature tracking is a requirement for many computer vision tasks such as indoor robot navigation. However, indoor scenes are characterized by poorly localizable features. As a result, indoor feature tracking without artificial markers is challenging and remains an attractive problem. We propose to solve this problem by constraining the locations of a large number of nondistinctive features by several planar homographies which are strategically computed using distinctive features. We experimentally show the need for multiple homographies and propose an illumination-invariant local-optimization scheme for motion refinement. The use of a large number of nondistinctive features within the constraints imposed by planar homographies allows us to gain robustness. Also, the lesser computation cost in estimating these nondistinctive features helps to maintain the efficiency of the proposed method. Our local-optimization scheme produces subpixel accurate feature motion. As a result, we are able to achieve robust and accurate feature tracking.

  2. Close-Range Tracking of Underwater Vehicles Using Light Beacons

    Science.gov (United States)

    Bosch, Josep; Gracias, Nuno; Ridao, Pere; Istenič, Klemen; Ribas, David

    2016-01-01

    This paper presents a new tracking system for autonomous underwater vehicles (AUVs) navigating in a close formation, based on computer vision and the use of active light markers. While acoustic localization can be very effective from medium to long distances, it is not so advantageous in short distances when the safety of the vehicles requires higher accuracy and update rates. The proposed system allows the estimation of the pose of a target vehicle at short ranges, with high accuracy and execution speed. To extend the field of view, an omnidirectional camera is used. This camera provides a full coverage of the lower hemisphere and enables the concurrent tracking of multiple vehicles in different positions. The system was evaluated in real sea conditions by tracking vehicles in mapping missions, where it demonstrated robust operation during extended periods of time. PMID:27023547

  3. Development of molecular markers linked to the 'Fiesta' linkage group 7 major QTL for fire blight resistance and their application for marker-assisted selection.

    Science.gov (United States)

    Khan, Muhammad A; Durel, Charles-Eric; Duffy, Brion; Drouet, Damien; Kellerhals, Markus; Gessler, Cesare; Patocchi, Andrea

    2007-06-01

    A fire blight resistance QTL explaining 34.3%-46.6% of the phenotypic variation was recently identified on linkage group 7 of apple cultivar 'Fiesta' (F7). However, markers flanking this QTL were AFLP and RAPD markers unsuitable for marker-assisted selection (MAS). Two RAPD markers bracketing the QTL have been transformed into SCAR (sequence-characterized amplified region) markers, and an SSR marker specific for the region was developed. Pedigree analysis of 'Fiesta' with these markers enabled tracking of the F7 QTL allele back to 'Cox's Orange Pippin'. Stability of the effect of this QTL allele in different backgrounds was analyzed by inoculating progeny plants of a cross between 'Milwa', a susceptible cultivar, and '1217', a moderately resistant cultivar, and a set of cultivars that carry or lack the allele conferring increased fire blight resistance. Progenies and cultivars that carried both markers were significantly more resistant than those that did not carry both markers, indicating high stability of the F7 QTL allele in different backgrounds. This stability and the availability of reproducible markers bracketing the QTL make this locus promising for use in MAS.

  4. Object Markers in Ikalanga

    Directory of Open Access Journals (Sweden)

    Rose Letsholo

    2013-01-01

    Full Text Available There is an on-going debate amongst linguists regarding the status of the object marker (OM. Some scholars argue that OMs are agreement morphology (Baker 2010, Riedel 2009 while others argue that OMs are pronominal and not agreement morphology (Nevins 2010, Kramer, under review, Labelle 2007, Demuth and Johnson 1990, Mchombo 2002. The purpose of this paper is to contribute to this debate using data from Ikalanga to support the view that OMs are pronominal clitics. I discuss evidence in favor of the agreement analysis as well as that in favor of the pronominal analysis. OMs in Ikalanga behave like agreement morphology in that they attach only to the verbal stem, only one OM occurs in a clause, and they share grammatical features (person, gender and number with the lexical NP with which they co-refer. However, there are many ways in which OMs behave like pronominals. For example, OMs do not vary in form according to the mood of a sentence or negation while subject markers, which I analyze as agreement morphemes do. They are not obligatory in Ikalanga sentences while subject markers are. OMs are not subject to locality constraints while agreement is. They can be bound by the subject (backward pronominalization, something unexpected of agreement and there is ample evidence to show that the lexical NP with which the OM co-refers is an adjunct, a fact which has been used in the literature to argue that the OM is pronominal in such a set up. The evidence in favor of the pronominal analysis however, is more compelling and therefore I conclude that OMs are pronominal clitics and not agreement morphology.

  5. 49 CFR 213.63 - Track surface.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Track surface. 213.63 Section 213.63..., DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Track Geometry § 213.63 Track surface. Each owner of the track to which this part applies shall maintain the surface of its track within the limits prescribed...

  6. Dipolar fluids under external perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Klapp, Sabine H L [Stranski-Laboratorium fuer Physikalische und Theoretische Chemie Sekretariat TC7, Technische Universitaet Berlin, Strasse des 17. Juni 124, D-10623 Berlin (Germany)

    2005-04-20

    We discuss recent developments and present new findings on the structural and phase properties of dipolar model fluids influenced by various external perturbations. We concentrate on systems of spherical particles with permanent (point) dipole moments. Starting from what is known about the three-dimensional systems, particular emphasis is given to dipolar fluids in different confining situations involving both simple and complex (disordered) pore geometries. Further topics concern the effect of quenched positional disorder, the influence of external (electric or magnetic) fields, and the fluid-fluid phase behaviour of various dipolar mixtures. It is demonstrated that due to the translational-orientational coupling and due to the long range of dipolar interactions even simple perturbations such as hard walls can have a profound impact on the systems. (topical review)

  7. External observer reflections on QBism

    CERN Document Server

    Khrennikov, Andrei

    2015-01-01

    In this short review I present my personal reflections on QBism. I have no intrinsic sympathy neither to QBism nor to subjective interpretation of probability in general. However, I have been following development of QBism from its very beginning, observing its evolution and success, sometimes with big surprise. Therefore my reflections on QBism can be treated as "external observer" reflections. I hope that my representation of this interpretation of quantum mechanics (QM) has some degree of objectivity. It may be useful for researchers who are interested in quantum foundations, but do not belong to the QBism-community, because I tried to analyze essentials of QBism critically (i.e., not just emphasizing its advantages, as in a typical publication of QBists). QBists may be interested as well - in comments of an external observer who monitored development of this approach to QM during last 16 years. The second part of the paper is devoted to interpretations of probability, objective versus subjective, and view...

  8. Firm Search for External Knowledge

    DEFF Research Database (Denmark)

    Sofka, Wolfgang; Grimpe, Christoph

    2012-01-01

    The innovation performance of modern firms is increasingly determined by their ability to search and absorb external knowledge. However, after a certain threshold firms "oversearch" their environment and innovation performance declines. In this paper, we argue that prior literature has largely...... ignored the institutional context that provides or denies access to external knowledge at the country level. Combining institutional and knowledge search theory, we suggest that the market orientation of the institutional environment and the magnitude of institutional change influence when firms begin...... to experience the negative performance effects of oversearch. Based on a comprehensive sample of almost 8,000 firms from ten European countries, we find that institutions matter considerably for firms' search activity. Higher market orientation of institutions increases the effectiveness of firms' search...

  9. MGR External Events Hazards Analysis

    Energy Technology Data Exchange (ETDEWEB)

    L. Booth

    1999-11-06

    The purpose and objective of this analysis is to apply an external events Hazards Analysis (HA) to the License Application Design Selection Enhanced Design Alternative 11 [(LADS EDA II design (Reference 8.32))]. The output of the HA is called a Hazards List (HL). This analysis supersedes the external hazards portion of Rev. 00 of the PHA (Reference 8.1). The PHA for internal events will also be updated to the LADS EDA II design but under a separate analysis. Like the PHA methodology, the HA methodology provides a systematic method to identify potential hazards during the 100-year Monitored Geologic Repository (MGR) operating period updated to reflect the EDA II design. The resulting events on the HL are candidates that may have potential radiological consequences as determined during Design Basis Events (DBEs) analyses. Therefore, the HL that results from this analysis will undergo further screening and analysis based on the criteria that apply during the performance of DBE analyses.

  10. Gait analysis using floor markers and inertial sensors.

    Science.gov (United States)

    Do, Tri Nhut; Suh, Young Soo

    2012-01-01

    In this paper, a gait analysis system which estimates step length and foot angles is proposed. A measurement unit, which consists of a camera and inertial sensors, is installed on a shoe. When the foot touches the floor, markers are recognized by the camera to obtain the current position and attitude. A simple planar marker with 4,096 different codes is used. These markers printed on paper are placed on the floor. When the foot is moving off the floor, the position and attitude are estimated using an inertial navigation algorithm. For accurate estimation, a smoother is proposed, where vision information and inertial sensor data are combined. Through experiments, it is shown that the proposed system can both track foot motion and estimate step length.

  11. Gait Analysis Using Floor Markers and Inertial Sensors

    Directory of Open Access Journals (Sweden)

    Young Soo Suh

    2012-02-01

    Full Text Available In this paper, a gait analysis system which estimates step length and foot angles is proposed. A measurement unit, which consists of a camera and inertial sensors, is installed on a shoe. When the foot touches the floor, markers are recognized by the camera to obtain the current position and attitude. A simple planar marker with 4,096 different codes is used. These markers printed on paper are placed on the floor. When the foot is moving off the floor, the position and attitude are estimated using an inertial navigation algorithm. For accurate estimation, a smoother is proposed, where vision information and inertial sensor data are combined. Through experiments, it is shown that the proposed system can both track foot motion and estimate step length.

  12. Robust FDI for A Ship-mounted Satellite Tracking Antenna: A Nonlinear Approach

    DEFF Research Database (Denmark)

    Soltani, Mohsen; Izadi-Zamanabadi, Roozbeh; Wisniewski, Rafal

    2008-01-01

    Overseas telecommunication is preserved by means of satellite communication. Tracking system postures the on-board antenna toward a chosen satellite while the external disturbances affect the antenna. Certain faults (beam sensor malfunction or signal blocking) cause interruption in the communicat......Overseas telecommunication is preserved by means of satellite communication. Tracking system postures the on-board antenna toward a chosen satellite while the external disturbances affect the antenna. Certain faults (beam sensor malfunction or signal blocking) cause interruption...... in the communication connection resulting in the loss of the tracking functionality. In this paper, an optimization based fault diagnosis system is proposed for the nonlinear model of the satellite tracking antenna (STA). The suggested method is able to estimate the fault for a class of nonlinear systems acting under...

  13. Network externalities across financial institutions

    OpenAIRE

    Castro Iragorri, Carlos Alberto; Preciado Pua, Sergio Andrés; Ordóñez Herrera, Juan Sebastián

    2016-01-01

    We propose and estimate a financial distress model that explicitly accounts for the interactions or spill-over effects between financial institutions, through the use of a spatial continuity matrix that is build from financial network data of inter bank transactions. Such setup of the financial distress model allows for the empirical validation of the importance of network externalities in determining financial distress, in addition to institution specific and macroeconomic covariates. The re...

  14. Externe Kosten in der Energiewirtschaft

    OpenAIRE

    Voß, Alfred; Friedrich, Rainer

    1994-01-01

    Als externe Effekte werden unbeteiligte Dritte betreffende Zusatzkosten oder Zusatznutzen verstanden, die sich in den jeweiligen Güterpreisen nicht wiederfinden und denen die Betroffenen nicht indifferent gegenüberstehen. Die gegenwärtige Energiebereitstellung und -nutzung ist in vielen Bereichen eine wesentliche Quelle der Belastung von Umwelt und Natur. Begriffe und Schlagworte wie Waldsterben, Tankerunglücke, Tschernobyl und Treibhauseffekt seien in diesem Zusammenhang erwähnt.

  15. Matching Games with Additive Externalities

    DEFF Research Database (Denmark)

    Branzei, Simina; Michalak, Tomasz; Rahwan, Talal

    2012-01-01

    Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas......, optimistic, and pessimistic behaviour, and provide both computational hardness results and polynomial-time algorithms for computing stable outcomes....

  16. ENDOSCOPIC DCR VERSUS EXTERNAL DCR

    Directory of Open Access Journals (Sweden)

    Rukma

    2015-04-01

    Full Text Available PURPOSE: To compare success rates of endoscopic dacryocystorhinostomy (DCR and external DCR for acquired nasolacrimal duct obstruction (NLDO. MATERIALS AND METHODS: A prospective comparative non randomized study of 64 patients who presented with acquired NLD obstruction to a tertiary hospital. They were fully evaluated to ascertain the site of obstruction and patients with distal obstruction were included in the study. 34 patients underwent endoscopic DCR and 30 patients underwent external DCR RESULTS: 64 patients were included in the study and 72 procedures carried out. Success was achieved in 65 cases and failure in 7. Of the 7 failed cases, anatomical obstruction at the fistula site was found in 3, whereas functional failure was found in 4. In our patients, endoscopic DCR had a significantly higher success rate than external DCR, 95.23% versus 83.33% (P = 0.03. CONCLUSIONS: The success rate of Endoscopic DCR for acquired NLDO in our group of patients was 95.23%, with endoscopic surgery showing better results.

  17. Conceptual challenges for internalising externalities

    DEFF Research Database (Denmark)

    Miguel, Brandão; Weidema, Bo Pedersen

    2013-01-01

    We analyse a number of different externalities to identify conceptual challenges for the practical implementation of their internalisation. Three issues were identified: i) The balance between compensation and technology change and the respective effects on the nominal and real GDP; ii) The relev......We analyse a number of different externalities to identify conceptual challenges for the practical implementation of their internalisation. Three issues were identified: i) The balance between compensation and technology change and the respective effects on the nominal and real GDP; ii......) The relevance and efficiency of different instruments for internalisation and compensation; and iii) Implementing internalisation over large geographical and temporal distances. We find taxation to be a more relevant and efficient tool for internalisation than insurance and litigation. With increasing...... geographical and especially temporal distance between the benefitting actor and the victim of the external cost, the involvement of a non-governmental intermediate actor becomes increasingly necessary to provide the short-term capital required to ensure a successful implementation....

  18. Individuals' insight into intrapersonal externalities

    Directory of Open Access Journals (Sweden)

    David J. Stillwell

    2012-07-01

    Full Text Available An intrapersonal externality exists when an individual's decisions affect the outcomes of her future decisions. It can result in decreasing or increasing average returns to the rate of consumption, as occurs in addiction or exercise. Experimentation using the Harvard Game, which models intrapersonal externalities, has found differences in decision making between drug users and control subjects, leading to the argument that these externalities influence the course of illicit drug use. Nevertheless, it is unclear how participants who behave optimally conceptualise the problem. We report two experiments using a simplified Harvard Game, which tested the differences in contingency knowledge between participants who chose optimally and participants who did not. Those who demonstrated optimal performance exhibited both a pattern of correct responses and systematic errors to questions about the payoff schedules. The pattern suggested that they learned explicit knowledge of the change in reinforcement on a trail-by-trial basis. They did not have, or need, a full knowledge of the historical interaction leading to each payoff. We also found no evidence of choice differences between participants who were given a guaranteed payment and participants who were paid contingent on their performance, but those given a guaranteed payment were able to report more contingency knowledge as the experiment progressed, suggesting that they explored more rather than settling into a routine. Experiment 2 showed that using a fixed inter-trial interval did not change the results.

  19. Solar Tracking System

    OpenAIRE

    Nguyen, Nam

    2016-01-01

    The goal of this thesis was to develop a laboratory prototype of a solar tracking system, which is able to enhance the performance of the photovoltaic modules in a solar energy system. The operating principle of the device is to keep the photovoltaic modules constantly aligned with the sunbeams, which maximises the exposure of solar panel to the Sun’s radiation. As a result, more output power can be produced by the solar panel. The work of the project included hardware design and implemen...

  20. Solar Tracking System

    OpenAIRE

    Nguyen, Nam

    2016-01-01

    The goal of this thesis was to develop a laboratory prototype of a solar tracking system, which is able to enhance the performance of the photovoltaic modules in a solar energy system. The operating principle of the device is to keep the photovoltaic modules constantly aligned with the sunbeams, which maximises the exposure of solar panel to the Sun’s radiation. As a result, more output power can be produced by the solar panel. The work of the project included hardware design and implemen...

  1. Use of wand markers on the pelvis in three dimensional gait analysis.

    Science.gov (United States)

    Smith, Martin; Curtis, Derek; Bencke, Jesper; Stebbins, Julie

    2013-09-01

    During clinical gait analysis, surface markers are placed over the anterior superior iliac spines (ASIS) of the pelvis. However, this can be problematic in overweight or obese subjects, where excessive adipose tissue can obscure the markers and prevent accurate tracking. A novel solution to this problem has previously been proposed and tested on a limited sample of healthy, adult subjects. This involves use of wand markers on the pelvis, to virtually recreate the ASIS markers. The method was tested here on 20 typical subjects presenting for clinical gait analysis (adults and children, including overweight subjects). The method was found to accurately reproduce ASIS markers, and allow calculation of pelvic angles to within one degree of angles produced by ASIS markers. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. LAMDA at TREC CDS track 2015: Clinical Decision Support Track

    Science.gov (United States)

    2015-11-20

    biomedical literature retrieval for clinical cases: a survey of the TREC 2014 CDS track," Information Retrieval Journal , pp. 1-36. [2] M. S. Simpson and...LAMDA at TREC CDS track 2015 Clinical Decision Support Track Moon Soo Cha, Woo-Jin Han, Garam Lee, Minsung Kim, Kyung-Ah Sohn* Department of...Information and Computer Engineering Ajou University Suwon, Republic of Korea (ckanstnzja; data; piratekl; kimmsql; kasohn)@ajou.ac.kr Abstract

  3. The use of CT density changes at internal tissue interfaces to correlate internal organ motion with an external surrogate

    Energy Technology Data Exchange (ETDEWEB)

    Gaede, Stewart; Yu, Edward; Van Dyk, Jake; Battista, Jerry [Radiation Oncology Program, London Regional Cancer Program, London, Ontario (Canada); Carnes, Gregory; Lee, Ting-Yim [Department of Medical Biophysics, University of Western Ontario, London, Ontario (Canada)

    2009-01-21

    The purpose of this paper is to describe a non-invasive method to monitor the motion of internal organs affected by respiration without using external markers or spirometry, to test the correlation with external markers, and to calculate any time shift between the datasets. Ten lung cancer patients were CT scanned with a GE LightSpeed Plus 4-Slice CT scanner operating in a cine mode. We retrospectively reconstructed the raw CT data to obtain consecutive 0.5 s reconstructions at 0.1 s intervals to increase image sampling. We defined regions of interest containing tissue interfaces, including tumour/lung interfaces that move due to breathing on multiple axial slices and measured the mean CT number versus respiratory phase. Tumour motion was directly correlated with external marker motion, acquired simultaneously, using the sample coefficient of determination, r{sup 2}. Only three of the ten patients showed correlation higher than r{sup 2} = 0.80 between tumour motion and external marker position. However, after taking into account time shifts (ranging between 0 s and 0.4 s) between the two data sets, all ten patients showed correlation better than r{sup 2} = 0.8. This non-invasive method for monitoring the motion of internal organs is an effective tool that can assess the use of external markers for 4D-CT imaging and respiratory-gated radiotherapy on a patient-specific basis.

  4. Tracking dynamics of two-dimensional continuous attractor neural networks

    Science.gov (United States)

    Fung, C. C. Alan; Wong, K. Y. Michael; Wu, Si

    2009-12-01

    We introduce an analytically solvable model of two-dimensional continuous attractor neural networks (CANNs). The synaptic input and the neuronal response form Gaussian bumps in the absence of external stimuli, and enable the network to track external stimuli by its translational displacement in the two-dimensional space. Basis functions of the two-dimensional quantum harmonic oscillator in polar coordinates are introduced to describe the distortion modes of the Gaussian bump. The perturbative method is applied to analyze its dynamics. Testing the method by considering the network behavior when the external stimulus abruptly changes its position, we obtain results of the reaction time and the amplitudes of various distortion modes, with excellent agreement with simulation results.

  5. The Timepix telescope for charged particle tracking

    Science.gov (United States)

    Hynds, Daniel

    2013-12-01

    The Timepix telescope has been developed as a general purpose tool for studying the performance of position sensitive charged particle detectors. Initiated as part of the infrastructure for the development of a new vertex detector for the LHCb experiment, the system was extended under the FP7 project AIDA to allow its use as an external facility by several groups within both the high energy and medical physics communities. Based at the CERN SPS, high track rates (up to 18 kHz), precise spatial resolution at the device under test (down to 1.6 μm), and a flexible integration method have all been demonstrated. The telescope is constructed using the Timepix ASIC, a hybrid pixel chip with an active area of 14×14 mm2.

  6. Hierarchical fringe tracking

    CERN Document Server

    Petrov, Romain G; Boskri, Abdelkarim; Folcher, Jean-Pierre; Lagarde, Stephane; Bresson, Yves; Benkhaldoum, Zouhair; Lazrek, Mohamed; Rakshit, Suvendu

    2014-01-01

    The limiting magnitude is a key issue for optical interferometry. Pairwise fringe trackers based on the integrated optics concepts used for example in GRAVITY seem limited to about K=10.5 with the 8m Unit Telescopes of the VLTI, and there is a general "common sense" statement that the efficiency of fringe tracking, and hence the sensitivity of optical interferometry, must decrease as the number of apertures increases, at least in the near infrared where we are still limited by detector readout noise. Here we present a Hierarchical Fringe Tracking (HFT) concept with sensitivity at least equal to this of a two apertures fringe trackers. HFT is based of the combination of the apertures in pairs, then in pairs of pairs then in pairs of groups. The key HFT module is a device that behaves like a spatial filter for two telescopes (2TSF) and transmits all or most of the flux of a cophased pair in a single mode beam. We give an example of such an achromatic 2TSF, based on very broadband dispersed fringes analyzed by g...

  7. Dust Devil Tracks

    Science.gov (United States)

    Reiss, Dennis; Fenton, Lori; Neakrase, Lynn; Zimmerman, Michael; Statella, Thiago; Whelley, Patrick; Rossi, Angelo Pio; Balme, Matthew

    2016-11-01

    Dust devils that leave dark- or light-toned tracks are common on Mars and they can also be found on the Earth's surface. Dust devil tracks (hereinafter DDTs) are ephemeral surface features with mostly sub-annual lifetimes. Regarding their size, DDT widths can range between ˜1 m and ˜1 km, depending on the diameter of dust devil that created the track, and DDT lengths range from a few tens of meters to several kilometers, limited by the duration and horizontal ground speed of dust devils. DDTs can be classified into three main types based on their morphology and albedo in contrast to their surroundings; all are found on both planets: (a) dark continuous DDTs, (b) dark cycloidal DDTs, and (c) bright DDTs. Dark continuous DDTs are the most common type on Mars. They are characterized by their relatively homogenous and continuous low albedo surface tracks. Based on terrestrial and martian in situ studies, these DDTs most likely form when surficial dust layers are removed to expose larger-grained substrate material (coarse sands of ≥500 μm in diameter). The exposure of larger-grained materials changes the photometric properties of the surface; hence leading to lower albedo tracks because grain size is photometrically inversely proportional to the surface reflectance. However, although not observed so far, compositional differences (i.e., color differences) might also lead to albedo contrasts when dust is removed to expose substrate materials with mineralogical differences. For dark continuous DDTs, albedo drop measurements are around 2.5 % in the wavelength range of 550-850 nm on Mars and around 0.5 % in the wavelength range from 300-1100 nm on Earth. The removal of an equivalent layer thickness around 1 μm is sufficient for the formation of visible dark continuous DDTs on Mars and Earth. The next type of DDTs, dark cycloidal DDTs, are characterized by their low albedo pattern of overlapping scallops. Terrestrial in situ studies imply that they are formed when sand

  8. Absolute measurements of the uranium concentration in thick samples using fission-track detectors

    Science.gov (United States)

    Enkelmann, Eva; Jonckheere, Raymond; Ratschbacher, Lothar

    2005-04-01

    We propose an improved equation for calculating the uranium concentration in thick samples based on induced fission-track counts in an external detector that takes into consideration (1) the fission-fragment ranges in the sample and external detector, (2) the etchable track length and (3) the track counting efficiency in the external detector. The values of these parameters have been determined by calculation and experiment and are shown to have a significant effect on the calculated uranium concentrations. The new equation was tested by calculating the uranium concentrations in standard uranium glasses (CN-5; IRMM-540R) and apatite samples (Durango; horse tooth) in which the uranium content was also determined with independent methods (INAA; ENAA; TIMS). The results show that: (1) accurate measurements with the fission-track method are feasible within a broad range of uranium concentrations and (2) uranium determinations based on standards are only accurate if the standard and sample are made of the same material. Because the absolute fission-tack dating method is also based on accurate thermal neutron fluence measurements and similar correction factors for the track registration and counting efficiencies, this study provides a strong endorsement for the fact that absolute fission-track ages are accurate.

  9. Seguimiento del contorno externo de la boca en imágenes de vídeo Outer Lip contour tracking in video images

    Directory of Open Access Journals (Sweden)

    Alexánder Ceballos

    2009-01-01

    Full Text Available El seguimiento preciso de la boca de una persona, cuando está hablando, es un desafío importante en varias aplicaciones, como la identificación de la cara o la interacción con el computador. La complejidad de forma, textura y color de la boca, y los cambios de iluminación y fondos de los posibles escenarios hacen que este sea aún un problema abierto. En este artículo se propone un algoritmo para el seguimiento del contorno externo de la boca, sin utilizar marcadores o alguna clase de maquillaje para resaltar los labios, basado en apariencia y en restricciones morfológicas definidas en el estándar MPEG-4. El algoritmo es robusto ante la presencia de barba, tono de piel y calidad de la imagen.An accurate tracking of a person's mouth when he/she is speaking is an important challenge in several applications such as face identification or interaction with computer. Complexity of shape, texture, and color of the mouth, as well as changes in lighting and backgrounds of possible scenarios makes of it an open problem yet. This article proposed an algorithm for a tracking of the mouth external contour without using markers or any kind of make-up for highlighting lips, based on appearance and morphological restrictions defined by the MPEG-4 Standard. Algorithm is robust before the presence of beard, skin tone, and image quality.

  10. Bayesian Tracking of Visual Objects

    Science.gov (United States)

    Zheng, Nanning; Xue, Jianru

    Tracking objects in image sequences involves performing motion analysis at the object level, which is becoming an increasingly important technology in a wide range of computer video applications, including video teleconferencing, security and surveillance, video segmentation, and editing. In this chapter, we focus on sequential Bayesian estimation techniques for visual tracking. We first introduce the sequential Bayesian estimation framework, which acts as the theoretic basis for visual tracking. Then, we present approaches to constructing representation models for specific objects.

  11. Making hurricane track data accessible

    OpenAIRE

    Slingsby, A.; Strachan, J.; Vidale, P.; Dykes, J.; Wood, J.

    2010-01-01

    Our interactive tool allows the exploration, validation and presentation of hundreds of years of dynamically simulated storm tracks. The tracks were generated as part of a research project to improve the risk assessment of tropical storm damage by the insurance industry. The main impact of the tool is that exploratory interactive visualisation is now being used by the storm track modellers to (a) validate and improve model outputs, (b) discuss outputs with their peers (c) obtain a better unde...

  12. REC Tracking Systems Design Guide

    Energy Technology Data Exchange (ETDEWEB)

    Meredith Wingate

    2004-02-03

    OAK-B135 The Design Guide is presented in three parts. Section II describes the need for REC tracking, the two principal tracking methods available, and, in simple terms, the operation of certificate-based systems. Section III presents the major issues in the design of certificate-based tracking systems and discusses the advantages and disadvantages of alternative solutions. Finally, Section IV offers design principles or recommendations for most of these issues.

  13. Health Research Information Tracking System

    Data.gov (United States)

    US Agency for International Development — The Health Research Information Tracking System (HRIT) is an expansion of the Child Health Research database that collects and maintains categorization, description,...

  14. Tracking by Machine Learning Methods

    CERN Document Server

    Jofrehei, Arash

    2015-01-01

    Current track reconstructing methods start with two points and then for each layer loop through all possible hits to find proper hits to add to that track. Another idea would be to use this large number of already reconstructed events and/or simulated data and train a machine on this data to find tracks given hit pixels. Training time could be long but real time tracking is really fast Simulation might not be as realistic as real data but tacking has been done for that with 100 percent efficiency while by using real data we would probably be limited to current efficiency.

  15. Reasonable Accommodation Information Tracking System

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reasonable Accommodation Information Tracking System (RAITS) is a case management system that allows the National Reasonable Accommodation Coordinator (NRAC) and...

  16. Official Union Time Tracking System

    Data.gov (United States)

    Social Security Administration — Official Union Time Tracking System captures the reporting and accounting of the representational activity for all American Federation of Government Employees (AFGE)...

  17. Localization and Tracking of Implantable Biomedical Sensors

    Directory of Open Access Journals (Sweden)

    Ilknur Umay

    2017-03-01

    Full Text Available Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems.

  18. Localization and Tracking of Implantable Biomedical Sensors.

    Science.gov (United States)

    Umay, Ilknur; Fidan, Barış; Barshan, Billur

    2017-03-13

    Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure) parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer) unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed) units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule) inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems.

  19. Localization and Tracking of Implantable Biomedical Sensors

    Science.gov (United States)

    Umay, Ilknur; Fidan, Barış; Barshan, Billur

    2017-01-01

    Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure) parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer) unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed) units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule) inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems. PMID:28335384

  20. Skepticism, Contextualism, Externalism and Modality

    Directory of Open Access Journals (Sweden)

    Ron Wilburn

    2006-12-01

    Full Text Available In this paper, I argue for the following claims. Contextualist strategies to tame or localize epistemic skepticism are hopeless if contextualist factors are construed internalistically. However, because efforts to contextualize externalism via subjunctive conditional analysis court circularity, it is only on an internalistic interpretation that contextualist strategies can even be motivated. While these claims do not give us an argument for skepticism, they do give us an argument that contextualism, as such, is not likely to provide us with an argument against skepticism.

  1. Leveraging External Sources of Innovation

    DEFF Research Database (Denmark)

    West, Joel; Bogers, Marcel

    2014-01-01

    own specific set of mechanisms and conditions. Integrating innovations has been mostly studied from an absorptive capacity perspective, with less attention given to the impact of competencies and culture (including “not invented here”). Commercializing innovations puts the most emphasis on how......” in a way inconsistent with earlier definitions in innovation management. The paper concludes with recommendations for future research that include examining the end-to-end innovation commercialization process, and studying the moderators and limits of leveraging external sources of innovation....

  2. External calibration technique of millimeter-wave cloud radar

    Science.gov (United States)

    Wen, Tao; Zhao, Zeng-Liang; Yao, Zhi-Gang; Han, Zhi-Gang; Guo, Lin-Da

    2016-10-01

    The millimeter-wave cloud radar can provide a large number of fine and reliable information for the inversion of cloud macro and micro parameters. A key link of using the millimeter-wave cloud radar to detect the cloud is that the radar must be calibrated. Due to the precision components and severe environment of millimeter-wave cloud radar, subtle changes may take place in the operation process of cloud radar, unless the cloud radar is calibrated regularly. Although the calibration system inside the cloud radar can track and monitor the main working parameters and correct the detection results, it fails to consider the characteristics of the antenna and the mutual influence among different components of cloud radar. Therefore, the external calibration for cloud radar system is very important. Combined with the actual situation of cloud radar under domestic onboard platform, this paper builds a complete external calibration technique process of cloud radar based on the calm sea, providing the theoretical support for the external calibration experiments of the airborne and even satellite-borne millimeter-wave cloud radar developed by our country.

  3. Arbitrary Finite-time Tracking Control for Magnetic Levitation Systems

    Directory of Open Access Journals (Sweden)

    Xuan-Toa Tran

    2014-10-01

    Full Text Available In this paper, an arbitrary finite-time tracking control (AFTC method is developed for magnetic levitation systems with uncertain dynamics and external disturbances. By introducing a novel augmented sliding-mode manifold function, the proposed method can eliminate the singular problem in traditional terminal sliding-mode control, as well as the reaching-phase problem. Moreover, the tracking errors can reach the reference value with faster convergence and better tracking precision in arbitrarily determined finite time. In addition, a fuzzy-arbitrary finite-time tracking control (F-AFTC scheme that combines a fuzzy technique with AFTC to enhance the robustness and sliding performance is also proposed. A fuzzy logic system is used to replace the discontinuous control term. Thus, the chattering phenomenon is resolved without degrading the tracking performance. The stability of the closed-loop system is guaranteed by the Lyapunov theory. Finally, the effectiveness of the proposed methods is illustrated by simulation and experimental study in a real magnetic levitation system.

  4. Stress tracking in thin bars by eigenstrain actuation

    Science.gov (United States)

    Schoeftner, J.; Irschik, H.

    2016-11-01

    This contribution focuses on stress tracking in slender structures. The axial stress distribution of a linear elastic bar is investigated, in particular, we seek for an answer to the following question: in which manner do we have to distribute eigenstrains, such that the axial stress in a bar is equal to a certain desired stress distribution, despite external forces or support excitations are present? In order to track a certain time- and space-dependent stress function, smart actuators, such as piezoelectric actuators, are needed to realize eigenstrains. Based on the equation of motion and the constitutive relation, which relate stress, strain, displacement and eigenstrains, an analytical solution for the stress tracking problem is derived. The starting point for the derivation of a solution for the stress tracking problem is a semi-positive definite integral depending on the error stress which is the difference between the actual stress and the desired stress. Our derived stress tracking theory is verified by two examples: first, a clamped-free bar which is harmonically excited is investigated. It is shown under which circumstances the axial stress vanishes at every location and at every time instant. The second example is a support-excited bar with end mass, where a desired stress profile is prescribed.

  5. Arbitrary Finite-time Tracking Control for Magnetic Levitation Systems

    Directory of Open Access Journals (Sweden)

    Xuan-Toa Tran

    2014-10-01

    Full Text Available In this paper, an arbitrary finite-time tracking control (AFTC method is developed for magnetic levitation systems with uncertain dynamics and external disturbances. By introducing a novel augmented sliding- mode manifold function, the proposed method can eliminate the singular problem in traditional terminal sliding-mode control, as well as the reaching-phase problem. Moreover, the tracking errors can reach the reference value with faster convergence and better tracking precision in arbitrarily determined finite time. In addition, a fuzzy-arbitrary finite-time tracking control (F- AFTC scheme that combines a fuzzy technique with AFTC to enhance the robustness and sliding performance is also proposed. A fuzzy logic system is used to replace the discontinuous control term. Thus, the chattering phenomenon is resolved without degrading the tracking performance. The stability of the closed-loop system is guaranteed by the Lyapunov theory. Finally, the effectiveness of the proposed methods is illustrated by simulation and experimental study in a real magnetic levitation system.

  6. A soft biomimetic tongue: model reconstruction and motion tracking

    Science.gov (United States)

    Lu, Xuanming; Xu, Weiliang; Li, Xiaoning

    2016-04-01

    A bioinspired robotic tongue which is actuated by a network of compressed air is proposed for the purpose of mimicking the movements of human tongue. It can be applied in the fields such as medical science and food engineering. The robotic tongue is made of two kinds of silicone rubber Ecoflex 0030 and PDMS with the shape simplified from real human tongue. In order to characterize the robotic tongue, a series of experiments were carried out. Laser scan was applied to reconstruct the static model of robotic tongue when it was under pressurization. After each scan, the robotic tongue was scattered into dense points in the same 3D coordinate system and the coordinates of each point were recorded. Motion tracking system (OptiTrack) was used to track and record the whole process of deformation dynamically during the loading and unloading phase. In the experiments, five types of deformation were achieved including roll-up, roll-down, elongation, groove and twist. Utilizing the discrete points generated by laser scan, the accurate parameterized outline of robotic tongue under different pressure was obtained, which could help demonstrate the static characteristic of robotic tongue. The precise deformation process under one pressure was acquired through the OptiTrack system which contains a series of digital cameras, markers on the robotic tongue and a set of hardware and software for data processing. By means of tracking and recording different process of deformation under different pressure, the dynamic characteristic of robotic tongue could be achieved.

  7. Urbanism on Track: Application of tracking technologies in urbanism

    NARCIS (Netherlands)

    Van der Hoeven, F.D.; Van Schaick, J.; Van der Spek, S.C.; Smit, M.G.J.

    2008-01-01

    Tracking technologies such as GPS, mobile phone tracking, video and RFID monitoring are rapidly becoming part of daily life. Technological progress offers huge possibilities for studying human activity patterns in time and space in new ways. Delft University of Technology (TU Delft) held an intern

  8. Fixed Scan Area Tracking with Track Splitting Filtering Algorithm

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar; Ahmed, Zaki

    2006-01-01

    to develop procedures that would enable a more general performance assessment. Therefore, a non-deterministic scenario is adopted, which basically provide a more appropriate approach for the evaluation of a tracking system based on track splitting filter algorithm.  The objects are generated within a fixed...

  9. Urbanism on Track: Application of tracking technologies in urbanism

    NARCIS (Netherlands)

    Van der Hoeven, F.D.; Van Schaick, J.; Van der Spek, S.C.; Smit, M.G.J.

    2008-01-01

    Tracking technologies such as GPS, mobile phone tracking, video and RFID monitoring are rapidly becoming part of daily life. Technological progress offers huge possibilities for studying human activity patterns in time and space in new ways. Delft University of Technology (TU Delft) held an

  10. Tracking migrating birds

    DEFF Research Database (Denmark)

    Willemoes, Mikkel

    Migratory movements of birds has always fascinated man and led to many questions concerning the ecological drivers behind, the necessary adaptations and the navigational abilities required. However, especially for the long-distance migrants, basic descriptions of their movements are still lacking...... and a forest reserve. In the degraded habitat all species used more space, although the consequence on bird density is less clear. Two manuscripts relate the migratory movements of a long-distance migrant with models of navigation. One compares model predictions obtained by simulation with actual movements...... in when and where the bird compensated for the displacement. The last paper investigates effects of habitat shading on the performance of light-level based geolocation and compares experimental data with data from real tracking studies. This illustrates some of the potential problems and limitations...

  11. Development of system using beam's eye view images to measure respiratory motion tracking errors in image-guided robotic radiosurgery system.

    Science.gov (United States)

    Inoue, Mitsuhiro; Shiomi, Hiroya; Iwata, Hiromitsu; Taguchi, Junichi; Okawa, Kohei; Kikuchi, Chie; Inada, Kosaku; Iwabuchi, Michio; Murai, Taro; Koike, Izumi; Tatewaki, Koshi; Ohta, Seiji; Inoue, Tomio

    2015-01-08

    The accuracy of the CyberKnife Synchrony Respiratory Tracking System (SRTS) is considered to be patient-dependent because the SRTS relies on an individual correlation between the internal tumor position (ITP) and the external marker position (EMP), as well as a prediction method to compensate for the delay incurred to adjust the position of the linear accelerator (linac). We aimed to develop a system for obtaining pretreatment statistical measurements of the SRTS tracking error by using beam's eye view (BEV) images, to enable the prediction of the patient-specific accuracy. The respiratory motion data for the ITP and the EMP were derived from cine MR images obtained from 23 patients. The dynamic motion phantom was used to reproduce both the ITP and EMP motions. The CyberKnife was subsequently operated with the SRTS, with a CCD camera mounted on the head of the linac. BEV images from the CCD camera were recorded during the tracking of a ball target by the linac. The tracking error was measured at 15 Hz using in-house software. To assess the precision of the position detection using an MR image, the positions of test tubes (determined from MR images) were compared with their actual positions. To assess the precision of the position detection of the ball, ball positions measured from BEV images were compared with values measured using a Vernier caliper. The SRTS accuracy was evaluated by determining the tracking error that could be identified with a probability of more than 95% (Ep95). The detection precision of the tumor position (determined from cine MR images) was < 0.2 mm. The detection precision of the tracking error when using the BEV images was < 0.2mm. These two detection precisions were derived from our measurement system and were not obtained from the SRTS. The median of Ep95 was found to be 1.5 (range, 1.0-3.5) mm. The difference between the minimum and maximum Ep95 was 2.5mm, indicating that this provides a better means of evaluating patient-specific SRTS

  12. Technical aspects of real time positron emission tracking for gated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chamberland, Marc; Xu, Tong, E-mail: txu@physics.carleton.ca [Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); McEwen, Malcolm R. [Ionizing Radiation Standards, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada)

    2016-02-15

    Purpose: Respiratory motion can lead to treatment errors in the delivery of radiotherapy treatments. Respiratory gating can assist in better conforming the beam delivery to the target volume. We present a study of the technical aspects of a real time positron emission tracking system for potential use in gated radiotherapy. Methods: The tracking system, called PeTrack, uses implanted positron emission markers and position sensitive gamma ray detectors to track breathing motion in real time. PeTrack uses an expectation–maximization algorithm to track the motion of fiducial markers. A normalized least mean squares adaptive filter predicts the location of the markers a short time ahead to account for system response latency. The precision and data collection efficiency of a prototype PeTrack system were measured under conditions simulating gated radiotherapy. The lung insert of a thorax phantom was translated in the inferior–superior direction with regular sinusoidal motion and simulated patient breathing motion (maximum amplitude of motion ±10 mm, period 4 s). The system tracked the motion of a {sup 22}Na fiducial marker (0.34 MBq) embedded in the lung insert every 0.2 s. The position of the was marker was predicted 0.2 s ahead. For sinusoidal motion, the equation used to model the motion was fitted to the data. The precision of the tracking was estimated as the standard deviation of the residuals. Software was also developed to communicate with a Linac and toggle beam delivery. In a separate experiment involving a Linac, 500 monitor units of radiation were delivered to the phantom with a 3 × 3 cm photon beam and with 6 and 10 MV accelerating potential. Radiochromic films were inserted in the phantom to measure spatial dose distribution. In this experiment, the period of motion was set to 60 s to account for beam turn-on latency. The beam was turned off when the marker moved outside of a 5-mm gating window. Results: The precision of the tracking in the IS

  13. Geo Issue Tracking System

    Science.gov (United States)

    Khakpour, Mohammad; Paulik, Christoph; Hahn, Sebastian

    2016-04-01

    Communication about remote sensing data quality between data providers and users as well as between the users is often difficult. The users have a hard time figuring out if a product has known problems over their region of interest and data providers have to spend a lot of effort to make this information available, if it exists. Scientific publications are one tool for communicating with the users base but they are static and mostly one way. As a data provider it is also often difficult to make feedback, received from users, available to the complete user base. The Geo Issue Tracking System (GeoITS) is an Open Source Web Application which has been developed to mitigate these problems. GeoITS combines a mapping interface (Google Maps) with a simple wiki platform. It allows users to give region specific feedback on a remote sensing product by drawing a polygon on the map and describing the problems they had using the remote sensing product in this area. These geolocated wiki entries are then viewable by other users as well as the data providers which can modify and extend the entries. In this way the conversations between the users and the data provider are no longer hidden in e.g. emails but open for all users of the dataset. This new kind of communication platform can enable better cooperation between users and data providers. It will also provide data providers with the ability to track problems their dataset might have in certain areas and resolve them with new product releases. The source code is available via http://github.com/TUW-GEO/geoits_dev A running instance can be tried at https://geoits.herokuapp.com/

  14. Speckle tracking technology for quantifying lung sliding.

    Science.gov (United States)

    Dori, Guy; Jakobson, Daniel J

    2016-06-01

    Ultrasound (US) is gaining recognition as a useful tool for assessing lung physiology and pathology. Yet, currently the skill of performing lung US is taught by experienced operators to novice ones, mainly by recognizing expected patterns. Recognizing the latter may be difficult and subjective. In this hypothesis we propose to apply a well-known and used image processing technology in echocardiography, speckle tracking (ST), to lung sliding - the marker of normal lung function. If implementing ST to lung sliding is technically feasible, several outcomes are expected: (1) Lung sliding will become an objective, operator-independent marker of normal lung function. (2) Subsequently, ST will provide normal values for lung sliding. (3) Lastly, the effects of pulmonary pathologies on lung sliding may be assessed. It is stressed, however, that the preliminary idea suggested here is limited to a single physiological phenomenon (lung sliding). Only when technical feasibility is demonstrated then ST technology may potentially be applied and investigated in other clinical settings of lung diseases. Copyright © 2016. Published by Elsevier Ltd.

  15. Robust Adaptive Fault-Tolerant Tracking Control of Three-Phase Induction Motor

    Directory of Open Access Journals (Sweden)

    Hossein Tohidi

    2014-01-01

    Full Text Available This paper deals with the problem of induction motor tracking control against actuator faults and external disturbances using the linear matrix inequalities (LMIs method and the adaptive method. A direct adaptive fault-tolerant tracking controller design method is developed based on Lyapunov stability theory and a constructive algorithm based on linear matrix inequalities for online tuning of adaptive and state feedback gains to stabilize the closed-loop system in order to reduce the fault effect with disturbance attenuation. Simulation results reveal the merits of proposed robust adaptive fault-tolerant tracking control scheme on an induction motor subjected to actuator faults.

  16. A Symplectic Multi-Particle Tracking Model for Self-Consistent Space-Charge Simulation

    CERN Document Server

    Qiang, Ji

    2016-01-01

    Symplectic tracking is important in accelerator beam dynamics simulation. So far, to the best of our knowledge, there is no self-consistent symplectic space-charge tracking model available in the accelerator community. In this paper, we present a two-dimensional and a three-dimensional symplectic multi-particle spectral model for space-charge tracking simulation. This model includes both the effect from external fields and the effect of self-consistent space-charge fields using a split-operator method. Such a model preserves the phase space structure and shows much less numerical emittance growth than the particle-in-cell model in the illustrative examples.

  17. Empirical Evaluation On External Debt Of Malaysia

    OpenAIRE

    Nor’Aznin Abu Bakar; Sallahuddin Hassan

    2011-01-01

    This study analyzes the effects of external debts on economic growth in Malaysia. The analysis is conducted both at aggregate and disaggregate levels. The empirical results are based on VAR estimates using GDP, external debts, capital accumulation, labor force and human capital. Estimation results at the aggregate level indicate that total external debts affect economic growth positively. In particular, one percentage point increase in total external debts generates 1.29 percentage point of e...

  18. Family context and externalizing correlates of childhood animal cruelty in adjudicated delinquents.

    Science.gov (United States)

    Walters, Glenn D; Noon, Alexandria

    2015-05-01

    The purpose of this study was to determine whether childhood animal cruelty is primarily a feature of family context or of externalizing behavior. Twenty measures of family context and proactive (fearlessness) and reactive (disinhibition) externalizing behavior were correlated with the retrospective accounts of childhood animal cruelty provided by 1,354 adjudicated delinquents. A cross-sectional analysis revealed that all 20 family context, proactive externalizing, and reactive externalizing variables correlated significantly with animal cruelty. Prospective analyses showed that when the animal cruelty variable was included in a regression equation with the 10 family context variables (parental arguing and fighting, parental drug use, parental hostility, and parental knowledge and monitoring of offspring behavior) or in a regression equation with the five reactive externalizing variables (interpersonal hostility, secondary psychopathy, weak impulse control, weak suppression of aggression, and short time horizon), it continued to predict future violent and income (property + drug) offending. The animal cruelty variable no longer predicted offending, however, when included in a regression equation with the five proactive externalizing variables (early onset behavioral problems, primary psychopathy, moral disengagement, positive outcome expectancies for crime, and lack of consideration for others). These findings suggest that while animal cruelty correlates with a wide range of family context and externalizing variables, it may serve as a marker of violent and nonviolent offending by virtue of its position on the proactive subdimension of the externalizing spectrum.

  19. Biochemical markers of bone turnover

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Deog Yoon [College of Medicine, Kyunghee Univ., Seoul (Korea, Republic of)

    1999-08-01

    Biochemical markers of bone turnover has received increasing attention over the past few years, because of the need for sensitivity and specific tool in the clinical investigation of osteoporosis. Bone markers should be unique to bone, reflect changes of bone less, and should be correlated with radiocalcium kinetics, histomorphometry, or changes in bone mass. The markers also should be useful in monitoring treatment efficacy. Although no bone marker has been established to meet all these criteria, currently osteocalcin and pyridinium crosslinks are the most efficient markers to assess the level of bone turnover in the menopausal and senile osteoporosis. Recently, N-terminal telopeptide (NTX), C-terminal telopeptide (CTX) and bone specific alkaline phosphatase are considered as new valid markers of bone turnover. Recent data suggest that CTX and free deoxypyridinoline could predict the subsequent risk of hip fracture of elderly women. Treatment of postmenopausal women with estrogen, calcitonin and bisphosphonates demonstrated rapid decrease of the levels of bone markers that correlated with the long-term increase of bone mass. Factors such as circadian rhythms, diet, age, sex, bone mass and renal function affect the results of biochemical markers and should be appropriately adjusted whenever possible. Each biochemical markers of bone turnover may have its own specific advantages and limitations. Recent advances in research will provide more sensitive and specific assays.

  20. Quantum Electrodynamics on background external fields

    CERN Document Server

    Marecki, P

    2003-01-01

    The quantum electrodynamics in presence of background external fields is developed. Modern methods of local quantum physics allow to formulate the theory on arbitrarily strong possibly time-dependent external fields. Non-linear observables which depend only locally on the external field are constructed. The tools necessary for this formulation, the parametrices of the Dirac operator, are investigated.

  1. 46 CFR 154.452 - External pressure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an enclosed...

  2. 46 CFR 64.19 - External pressure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false External pressure. 64.19 Section 64.19 Shipping COAST... HANDLING SYSTEMS Standards for an MPT § 64.19 External pressure. (a) A tank without a vacuum breaker must be designed to withstand an external pressure of 71/2 psig or more. (b) A tank with a vacuum breaker...

  3. 49 CFR 195.108 - External pressure.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false External pressure. 195.108 Section 195.108 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY... PIPELINE Design Requirements § 195.108 External pressure. Any external pressure that will be exerted on the...

  4. Quantum electrodynamics on background external fields

    OpenAIRE

    2003-01-01

    The quantum electrodynamics in presence of background external fields is developed. Modern methods of local quantum physics allow to formulate the theory on arbitrarily strong possibly time-dependent external fields. Non-linear observables which depend only locally on the external field are constructed. The tools necessary for this formulation, the parametrices of the Dirac operator, are investigated.

  5. Study of heat treatment parameters for large-scale hydraulic steel gate track

    Directory of Open Access Journals (Sweden)

    Ping-zhou CAO

    2013-10-01

    Full Text Available In order to enhance external hardness and strength, a large-scale hydraulic gate track should go through heat treatment. The current design method of hydraulic gate wheels and tracks is based on Hertz contact linear elastic theory, and does not take into account the changes in mechanical properties of materials caused by heat treatment. In this study, the heat treatment parameters were designed and analyzed according to the bearing mechanisms of the wheel and track. The quenching process of the track was simulated by the ANSYS program, and the temperature variation, residual stress, and deformation were obtained and analyzed. The metallurgical structure field after heat treatment was predicted by the method based on time-temperature-transformation (TTT curves. The results show that the analysis method and designed track heat treatment process are feasible, and can provide a reference for practical projects.

  6. Low velocity tracking control-based ADRC for large-scale telescope system

    Science.gov (United States)

    Cai, Huaxiang; Huang, Yongmei; Du, Junfeng; Tang, Tao; Zuo, Dan

    2015-10-01

    In this paper, an improved Active Disturbance Rejection control (ADRC) method is proposed to enhance the tracking precision of telescope if the telescope runs in a low velocity. Low velocity telescope system usually suffers some obvious nonlinear disturbances, such as nonlinear friction and unknown external disturbance. Thereby, to ensure the tracking precision, multiple loops control structure is a common control method in telescope system, which includes current loop, velocity loop and position loop. The proposed control method is used in the velocity loop which consists of a PD controller and an Extend State Observer (ESO). The ESO is designed to estimate the disturbance involved in the telescope system. Besides, the PD controller is designed to stabilize the closed-loop system. Furthermore, this control method theoretically guarantees a prescribed tracking performance and final tracking accuracy. Finally, the experiment results show that the proposed control method has excellent performance for reducing the tracking error of low velocity.

  7. Optimal Geometrical Set for Automated Marker Placement to Virtualized Real-Time Facial Emotions.

    Directory of Open Access Journals (Sweden)

    Vasanthan Maruthapillai

    Full Text Available In recent years, real-time face recognition has been a major topic of interest in developing intelligent human-machine interaction systems. Over the past several decades, researchers have proposed different algorithms for facial expression recognition, but there has been little focus on detection in real-time scenarios. The present work proposes a new algorithmic method of automated marker placement used to classify six facial expressions: happiness, sadness, anger, fear, disgust, and surprise. Emotional facial expressions were captured using a webcam, while the proposed algorithm placed a set of eight virtual markers on each subject's face. Facial feature extraction methods, including marker distance (distance between each marker to the center of the face and change in marker distance (change in distance between the original and new marker positions, were used to extract three statistical features (mean, variance, and root mean square from the real-time video sequence. The initial position of each marker was subjected to the optical flow algorithm for marker tracking with each emotional facial expression. Finally, the extracted statistical features were mapped into corresponding emotional facial expressions using two simple non-linear classifiers, K-nearest neighbor and probabilistic neural network. The results indicate that the proposed automated marker placement algorithm effectively placed eight virtual markers on each subject's face and gave a maximum mean emotion classification rate of 96.94% using the probabilistic neural network.

  8. Conserved amino acid markers from past influenza pandemic strains

    Directory of Open Access Journals (Sweden)

    Vitalis Elizabeth A

    2009-04-01

    Full Text Available Abstract Background Finding the amino acid mutations that affect the severity of influenza infections remains an open and challenging problem. Of special interest is better understanding how current circulating influenza strains could evolve into a new pandemic strain. Influenza proteomes from distinct viral phenotype classes were searched for class specific amino acid mutations conserved in past pandemics, using reverse engineered linear classifiers. Results Thirty-four amino acid markers associated with host specificity and high mortality rate were found. Some markers had little impact on distinguishing the functional classes by themselves, however in combination with other mutations they improved class prediction. Pairwise combinations of influenza genomes were checked for reassortment and mutation events needed to acquire the pandemic conserved markers. Evolutionary pathways involving H1N1 human and swine strains mixed with avian strains show the potential to acquire the pandemic markers with a double reassortment and one or two amino acid mutations. Conclusion The small mutation combinations found at multiple protein positions associated with viral phenotype indicate that surveillance tools could monitor genetic variation beyond single point mutations to track influenza strains. Finding that certain strain combinations have the potential to acquire pandemic conserved markers through a limited number of reassortment and mutation events illustrates the potential for reassortment and mutation events to lead to new circulating influenza strains.

  9. Satellite and acoustic tracking device

    KAUST Repository

    Berumen, Michael L.

    2014-02-20

    The present invention relates a method and device for tracking movements of marine animals or objects in large bodies of water and across significant distances. The method and device can track an acoustic transmitter attached to an animal or object beneath the ocean surface by employing an unmanned surface vessel equipped with a hydrophone array and GPS receiver.

  10. CONTRACT ADMINISTRATIVE TRACKING SYSTEM (CATS)

    Science.gov (United States)

    The Contract Administrative Tracking System (CATS) was developed in response to an ORD NHEERL, Mid-Continent Ecology Division (MED)-recognized need for an automated tracking and retrieval system for Cost Reimbursable Level of Effort (CR/LOE) Contracts. CATS is an Oracle-based app...

  11. Do Not Track for Europe

    NARCIS (Netherlands)

    Zuiderveen Borgesius, F.J.; McDonald, A.M.

    2015-01-01

    Online tracking is the subject of heated debates. In Europe, policy debates focus on the e-Privacy Directive, which requires firms to obtain the consumer’s consent for the use of tracking cookies and similar technologies. A common complaint about the Directive is that clicking "I agree" to hundreds

  12. Improved code-tracking loop

    Science.gov (United States)

    Laflame, D. T.

    1980-01-01

    Delay-locked loop tracks pseudonoise codes without introducing dc timing errors, because it is not sensitive to gain imbalance between signal processing arms. "Early" and "late" reference codes pass in combined form through both arms, and each arm acts on both codes. Circuit accomodates 1 dB weaker input signals with tracking ability equal to that of tau-dither loops.

  13. Simultaneous tracking and activity recognition

    DEFF Research Database (Denmark)

    Manfredotti, Cristina Elena; Fleet, David J.; Hamilton, Howard J.

    2011-01-01

    Many tracking problems involve several distinct objects interacting with each other. We develop a framework that takes into account interactions between objects allowing the recognition of complex activities. In contrast to classic approaches that consider distinct phases of tracking and activity...

  14. Making Sense of Dinosaur Tracks

    Science.gov (United States)

    MacKenzie, Ann Haley; McDowell, Brian

    2012-01-01

    What do paleontologists, dinosaur tracks, and the nature of science have in common? They're combined here in an inquiry activity where students use methods of observation and inference to devise evidence-based explanations for the data they collect about dinosaur tracks, much like the methods used by paleontologists. Students then debate the…

  15. CONTRACT ADMINISTRATIVE TRACKING SYSTEM (CATS)

    Science.gov (United States)

    The Contract Administrative Tracking System (CATS) was developed in response to an ORD NHEERL, Mid-Continent Ecology Division (MED)-recognized need for an automated tracking and retrieval system for Cost Reimbursable Level of Effort (CR/LOE) Contracts. CATS is an Oracle-based app...

  16. Comparative accuracy of radiostereometric and optical tracking systems.

    Science.gov (United States)

    Kedgley, Angela E; Birmingham, Trevor; Jenkyn, Thomas R

    2009-06-19

    This study aims to quantify and compare the accuracy of traditional radiostereometric analysis (RSA), fluoroscopic RSA (fRSA), and optical tracking systems. Three phantoms were constructed, each having three stainless steel spheres and three reflective markers. One phantom was mounted to the base of a precision cross-slide table, one to the base of a precision rotation table, and the third was mounted to each moveable tabletop. Two dial-gauges, rigidly mounted to the cross-slide table and rotation table, quantified translations and rotations. Two fluoroscopy units placed orthogonally tracked the steel spheres while a four-camera optical motion capture system tracked the reflective markers in three-dimensional space. RSA was performed with both digital radiography and fluoroscopy. Three axes of translation were tested: parallel to one fluoroscopy image, parallel to the other fluoroscopy image, and at approximately 45 degrees to each image. One axis of rotation was tested. Intraclass correlation coefficients indicated excellent agreement between the actual (dial-gauge) and measured translations for all modalities (ICCs>0.99) and excellent agreement between actual and measured rotations for RSA and fRSA (ICCs>0.99). Standard errors of measurement ranged from 0.032 mm and 0.121 degrees for RSA, to 0.040 mm and 0.229 degrees for fRSA, and to 0.109 mm and 0.613 degrees for optical tracking. Differences between actual and measured translations along the 45 degrees axis were significantly smaller than the two parallel axes. These findings suggest that under ideal conditions, accuracy of fRSA is comparable to traditional RSA, and superior to optical tracking. Accuracy is highest when measured at 45 degrees to the fluoroscopy units.

  17. A Laser Scanning Tracking Method

    Science.gov (United States)

    Xu, Gaoyue; Hu, Baoli; Wang, Jiangping

    1988-04-01

    In this paper, a new tracking approach, a laser scanning tracking method (LSTM) is proposed. The LSTM has been designed to track a cylindrical retroreflective target mounted on the object, which makes plane motion. The retroreflector pasted by scotchlite reflective sheeting (mad. in 3M ,0.) i s located by scanning a laser beam in holizontal. When the retroreflector is struck, its position that is azimuth is read by microcomputer and the aiming device is servocontrolled by microcomputer according to this azimuth immediately. This is a step-by-step tracking method. The time of servo-reponse is less than one millisecona in actual tests. The angular accuracy is less than 0.5 milliradian. The track angular velocity is greater than one radian/second.

  18. Particle Filter Tracking without Dynamics

    Directory of Open Access Journals (Sweden)

    Jaime Ortegon-Aguilar

    2007-01-01

    Full Text Available People tracking is an interesting topic in computer vision. It has applications in industrial areas such as surveillance or human-machine interaction. Particle Filters is a common algorithm for people tracking; challenging situations occur when the target's motion is poorly modelled or with unexpected motions. In this paper, an alternative to address people tracking is presented. The proposed algorithm is based in particle filters, but instead of using a dynamical model, it uses background subtraction to predict future locations of particles. The algorithm is able to track people in omnidirectional sequences with a low frame rate (one or two frames per second. Our approach can tackle unexpected discontinuities and changes in the direction of the motion. The main goal of the paper is to track people from laboratories, but it has applications in surveillance, mainly in controlled environments.

  19. 49 CFR 213.331 - Track surface.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Track surface. 213.331 Section 213.331... Track surface. (a) For a single deviation in track surface, each owner of the track to which this subpart applies shall maintain the surface of its track within the limits prescribed in the...

  20. NucliTrack: An integrated nuclei tracking application.

    Science.gov (United States)

    Cooper, Sam; Barr, Alexis R; Glen, Robert; Bakal, Chris

    2017-06-20

    Live imaging studies give unparalleled insight into dynamic single cell behaviours and fate decisions. However, the challenge of reliably tracking single cells over long periods of time limits both the throughput and ease with which such studies can be performed. Here, we present NucliTrack, a cross platform solution for automatically segmenting, tracking and extracting features from fluorescently-labelled nuclei. NucliTrack performs similarly to other state-of-the-art cell tracking algorithms, but NucliTrack's interactive, graphical interface makes it significantly more user friendly. NucliTrack is available as a free, cross platform application, and open source Python package. Installation details and documentation are at: http://nuclitrack.readthedocs.io/en/latest / A video guide can be viewed online: https://www.youtube.com/watch?v=J6e0D9F-qSU Source code is available through Github: https://github.com/samocooper/nuclitrack . A Matlab toolbox is also available at: https://uk.mathworks.com/matlabcentral/fileexchange/61479-samocooper-nuclitrack-matlab. sam@socooper.com. Supplementary data are available at Bioinformatics online.

  1. Externally Wetted Ionic Liquid Thruster

    Science.gov (United States)

    Lozano, P.; Martinez-Sanchez, M.; Lopez-Urdiales, J. M.

    2004-10-01

    This paper presents initial developments of an electric propulsion system based on ionic liquid ion sources (ILIS). Propellants are ionic liquids, which are organic salts with two important characteristics; they remain in the liquid state at room temperature and have negligible vapor pressure, thus allowing their use in vacuum. The working principles of ILIS are similar to those of liquid metal ion sources (LMIS), in which a Taylor cone is electrostatically formed at the tip of an externally wetted needle while ions are emitted directly from its apex. ILIS have the advantage of being able to produce negative ions that have similar masses than their positive counterparts with similar current levels. This opens up the possibility of achieving plume electrical neutrality without electron emitters. The possible multiplexing of these emitters is discussed in terms of achievable thrust density for applications other than micro-propulsion.

  2. External symmetry in general relativity

    CERN Document Server

    Cotaescu, I I

    2000-01-01

    We propose a generalization of the isometry transformations to the geometric context of the field theories with spin where the local frames are explicitly involved. We define the external symmetry transformations as isometries combined with suitable tetrad gauge transformations and we show that these form a group which is locally isomorphic with the isometry one. We point out that the symmetry transformations that leave invariant the equations of the fields with spin have generators with specific spin terms which represent new physical observables. The examples we present are the generators of the central symmetry and those of the maximal symmetries of the de Sitter and anti-de Sitter spacetimes derived in different tetrad gauge fixings. Pacs: 04.20.Cv, 04.62.+v, 11.30.-j

  3. Feature tracking and aging

    Directory of Open Access Journals (Sweden)

    Rémy eAllard

    2013-07-01

    Full Text Available There are conflicting results regarding the effect of aging on second-order motion processing (i.e., motion defined by attributes other than luminance, such as contrast. Two studies (Habak & Faubert, 2000; Tang & Zhou, 2009 found that second-order motion processing was more vulnerable to aging than first-order motion processing. Conversely, Billino, Braun, Bremmer and Gegenfurtner (2011 recently found that aging affected first- and second-order motion processing by similar proportions. These three studies used contrast-defined motion as a second-order stimulus, but there can be at least two potential issues when using such a stimulus to evaluate age-related sensitivity losses. First, it has been shown that the motion system processing contrast-defined motion varies depending on the stimulus parameters. Thus, although all these three studies assumed that their contrast-defined motion was processed by a low-level second-order motion system, this was not necessarily the case. The second potential issue is that contrast-defined motion consists in a contrast modulation of a texture rich in high spatial frequencies and aging mainly affects contrast sensitivity at high spatial frequencies. Consequently, some age-related sensitivity loss to second-order motion could be due to a lower sensitivity to the texture rather than to motion processing per se. To avoid these two potential issues, we used a second-order motion stimulus void of high spatial frequencies and which has been shown to be processed by a high-level feature tracking motion system, namely fractal rotation (Lagacé-Nadon, Allard, & Faubert, 2009. We found an age-related deficit on second-order motion processing at all temporal frequencies including the ones for which no age-related effect on first-order motion processing was observed. We conclude that aging affects the ability to track features. Previous age-related results on second-order and global motion processing are discussed in light

  4. Minimal marker set for center of mass estimation in running.

    Science.gov (United States)

    Halvorsen, Kjartan; Eriksson, Martin; Gullstrand, Lennart; Tinmark, Fredrik; Nilsson, Johnny

    2009-11-01

    The purpose was to study the validity of a recently proposed method [Forsell C, Halvorsen K. A method for determining minimal sets of markers for the estimation of center of mass, linear and angular momentum. Journal of Biomechanics 2009;42(3):361-5] for estimating the trajectory of the whole-body center of mass (CoM) in the case of running at velocities ranging from 10 to 22 km h(-1). The method gives an approximation to the CoM using the position of fewer markers on the body than the standard method of tracking each segment of the body. Fourteen male athletes participated. A standard method for determining the CoM from a model of 13 segments and using the position of 36 markers was used as reference method. Leave-one-out cross-validation revealed errors that decreased with increasing number of markers used in the approximative method. Starting from four markers, the error in absolute position of the CoM decreased from 15 mm to 3 mm in each direction. For the velocity of the CoM the estimation bias was neglectable, and the random error decreased from 0.15 to 0.05 m s(-1). The inter-subject and intra-subject variability in the estimated model parameters increased with increasing number of markers. The method worked well also when applied to running at velocities outside the range of velocities in the data used to determine the model parameters. The results indicate that a model using 10 markers represents a good trade-off between simplicity and accuracy, but users must take into account requirements of their specific applications.

  5. Urinary markers in bladder cancer.

    NARCIS (Netherlands)

    Vrooman, O.P.; Witjes, J.A.

    2008-01-01

    OBJECTIVES: Many markers for the detection of bladder cancers have been tested. Almost all urinary markers reported are better than cytology with regard to sensitivity, but they score lower in specificity. The purpose of this review is to highlight the most important urinary biomarkers studied and

  6. The Effects of Water Matrix on Decay of Human Fecal Molecular Markers and Campylobacter spp.

    Science.gov (United States)

    Although molecular source tracking for human fecal contamination is used on a wide range of sample types, little is known about comparative decay of proposed molecular markers under different conditions, or correlation with pathogen decay. Our purpose was to measure correlations ...

  7. The Effects of Water Matrix on Decay of Human Fecal Molecular Markers and Campylobacter spp.

    Science.gov (United States)

    Although molecular source tracking for human fecal contamination is used on a wide range of sample types, little is known about comparative decay of proposed molecular markers under different conditions, or correlation with pathogen decay. Our purpose was to measure correlations ...

  8. Markers of renal function tests

    Directory of Open Access Journals (Sweden)

    Shivaraj Gowda

    2010-04-01

    Full Text Available Background: The markers of renal function test assess the normal functioning of kidneys. These markers may be radioactive and non radioactive. They indicate the glomerular filtration rate, concentrating and diluting capacity of kidneys (tubular function. If there is an increase or decrease in the valves of these markers it indicates dysfunction of kidney. Aim: The aim of this review is to compare and analyze the present and newer markers of renal function tests which help in diagnosis of clinical disorders. Material & Methods: An extensive literature survey was done aiming to compare and compile renal function tests makers required in diagnosis of diseases. Results: Creatinine, urea, uric acid and electrolytes are makers for routine analysis whereas several studies have confirmed and consolidated the usefulness of markers such as cystatin C and β-Trace Protein. Conclusion: We conclude that further investigation is necessary to define these biomarkers in terms of usefulness in assessing renal function.

  9. The Motif Tracking Algorithm

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The search for patterns or motifs in data represents a problem area of key interest to finance and economic researchers. In this paper, we introduce the motif tracking algorithm (MTA), a novel immune inspired (IS) pattern identification tool that is able to identify unknown motifs of a non specified length which repeat within time series data. The power of the algorithm comes from the fact that it uses a small number of parameters with minimal assumptions regarding the data being examined or the underlying motifs. Our interest lies in applying the algorithm to financial time series data to identify unknown patterns that exist. The algorithm is tested using three separate data sets. Particular suitability to financial data is shown by applying it to oil price data. In all cases, the algorithm identifies the presence of a motif population in a fast and efficient manner due to the utilization of an intuitive symbolic representation.The resulting population of motifs is shown to have considerable potential value for other applications such as forecasting and algorithm seeding.

  10. The Motif Tracking Algorithm

    CERN Document Server

    Wilson, William; Aickelin, Uwe; 10.1007/s11633.008.0032.0

    2010-01-01

    The search for patterns or motifs in data represents a problem area of key interest to finance and economic researchers. In this paper we introduce the Motif Tracking Algorithm, a novel immune inspired pattern identification tool that is able to identify unknown motifs of a non specified length which repeat within time series data. The power of the algorithm comes from the fact that it uses a small number of parameters with minimal assumptions regarding the data being examined or the underlying motifs. Our interest lies in applying the algorithm to financial time series data to identify unknown patterns that exist. The algorithm is tested using three separate data sets. Particular suitability to financial data is shown by applying it to oil price data. In all cases the algorithm identifies the presence of a motif population in a fast and efficient manner due to the utilisation of an intuitive symbolic representation. The resulting population of motifs is shown to have considerable potential value for other ap...

  11. Otiy: Loactors tracking nodes

    CERN Document Server

    Boc, Mathias; de Amorim, Marcelo dias

    2007-01-01

    We propose Otiy, a node-centric location service that limits the impact of location updates generate by mobile nodes in IEEE802.11-based wireless mesh networks. Existing location services use node identifiers to determine the locator (aka anchor) that is responsible for keeping track of a node's location. Such a strategy can be inefficient because: (i) identifiers give no clue on the node's mobility and (ii) locators can be far from the source/destination shortest path, which increases both location delays and bandwidth consumption. To solve these issues, Otiy introduces a new strategy that identifies nodes to play the role of locators based on the likelihood of a destination to be close to these nodes- i.e., locators are identified depending on the mobility pattern of nodes. Otiy relies on the cyclic mobility patterns of nodes and creates a slotted agenda composed of a set of predicted locations, defined according to the past and present patterns of mobility. Correspondent nodes fetch this agenda only once a...

  12. Polymorphic microsatellite markers in the brown seaweed Fucus vesiculosus.

    Science.gov (United States)

    Candeias, Rui; Casado-Amezúa, Pilar; Pearson, Gareth A; Serrão, Ester A; Teixeira, Sara

    2015-03-08

    Fucus vesiculosus is a brown seaweed dominant on temperate rocky shores of the northern hemisphere and, is typically distributed in the mid-upper intertidal zone. It is an external fertilizer that reproduces sexually, providing an excellent model to address conflicting theories related to mating systems and sexual selection. Microsatellite markers have been reported for several Fucus species, however the genomic libraries from where these markers have been isolated, have originated from two or more species pooled together (F. vesiculosus and F. serratus in one library; F. vesiculosus, F. serratus and Ascophyllum nodosum in a second library), or when the genomic DNA originated from only one species it was from Fucus spiralis. Although these markers cross-amplify F. vesiculosus individuals, the level of polymorphism has been low for relatedness studies. The microsatellite markers described here were obtained from an enriched genomic library, followed by 454 pyrosequencing. A total of 9 microsatellite markers were tested across 44 individuals from the North of Portugal. The mean number of alleles across loci was 8.7 and the gene diversity 0.67. The high variability displayed by these microsatellite loci should be useful for paternity analysis, assessing variance of reproductive success and in estimations of genetic variation within and between populations.

  13. Use of Plant Hydrocarbons as External Markers to Measure Voluntary Intake and Digestibility in Beef Steers

    Science.gov (United States)

    Calculating dry matter intake of grazing herbivores has been an issue in determining factors such as efficiency and digestibility of forages. Two experiments were conducted using alkanes to validate analytical methods with oven-dried and freeze-dried samples, to compare and contrast measured and pre...

  14. Track guided self-driven container wagon

    NARCIS (Netherlands)

    Hansen, I.A.

    1999-01-01

    The linear motor consists of a series of stator coils (2) located along the Track guided self-driven container wagon Track guided self-driven container wagon track and a reaction rail (3) fitted under the wagon chassis (4).

  15. ANNOTATION SUPPORTED OCCLUDED OBJECT TRACKING

    Directory of Open Access Journals (Sweden)

    Devinder Kumar

    2012-08-01

    Full Text Available Tracking occluded objects at different depths has become as extremely important component of study for any video sequence having wide applications in object tracking, scene recognition, coding, editing the videos and mosaicking. The paper studies the ability of annotation to track the occluded object based on pyramids with variation in depth further establishing a threshold at which the ability of the system to track the occluded object fails. Image annotation is applied on 3 similar video sequences varying in depth. In the experiment, one bike occludes the other at a depth of 60cm, 80cm and 100cm respectively. Another experiment is performed on tracking humans with similar depth to authenticate the results. The paper also computes the frame by frame error incurred by the system, supported by detailed simulations. This system can be effectively used to analyze the error in motion tracking and further correcting the error leading to flawless tracking. This can be of great interest to computer scientists while designing surveillance systems etc.

  16. Context-aware visual tracking.

    Science.gov (United States)

    Yang, Ming; Wu, Ying; Hua, Gang

    2009-07-01

    Enormous uncertainties in unconstrained environments lead to a fundamental dilemma that many tracking algorithms have to face in practice: Tracking has to be computationally efficient, but verifying whether or not the tracker is following the true target tends to be demanding, especially when the background is cluttered and/or when occlusion occurs. Due to the lack of a good solution to this problem, many existing methods tend to be either effective but computationally intensive by using sophisticated image observation models or efficient but vulnerable to false alarms. This greatly challenges long-duration robust tracking. This paper presents a novel solution to this dilemma by considering the context of the tracking scene. Specifically, we integrate into the tracking process a set of auxiliary objects that are automatically discovered in the video on the fly by data mining. Auxiliary objects have three properties, at least in a short time interval: 1) persistent co-occurrence with the target, 2) consistent motion correlation to the target, and 3) easy to track. Regarding these auxiliary objects as the context of the target, the collaborative tracking of these auxiliary objects leads to efficient computation as well as strong verification. Our extensive experiments have exhibited exciting performance in very challenging real-world testing cases.

  17. Harmonization of European track quality

    Directory of Open Access Journals (Sweden)

    Popović Zdenka

    2014-01-01

    Full Text Available This paper deals with characterisation of track geometry, track measuring and recording system, as well as geometric quality levels. The legal framework and state of the art in the field of harmonization of track geometry technical regulation in the Republic of Serbia were presented. In particular, the paper discusses the European standard EN 13848 Series (Parts 1-6. Principal track geometric parameters were analyzed according to EN 13848-1. Track geometric quality levels were examined according to EN 13848-5. The evaluation of track geometry quality according to prEN 13848-6 was analyzed as well. The objective of creation of the European standard EN 13848 Series (Parts 1-6 was defining a unique approach for the evaluation of track geometry quality of various European railway infrastructures. The Institute for Standardization of Serbia has adopted and published five of six parts of this standard. This paper is a part of an effort to harmonize the Serbian railway technical regulations with those of the European Union. .

  18. The Effects of the Fast Track Preventive Intervention on the Development of Conduct Disorder across Childhood

    Science.gov (United States)

    Child Development, 2011

    2011-01-01

    The impact of the Fast Track intervention on externalizing disorders across childhood was examined. Eight hundred-ninety-one early-starting children (69% male; 51% African American) were randomly assigned by matched sets of schools to intervention or control conditions. The 10-year intervention addressed parent behavior-management, child social…

  19. CDC National Environmental Public Health Tracking Network (Tracking Network)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Environmental Public Health Tracking Network is a system of integrated health, exposure, and hazard information and data from a variety of national,...

  20. Neural network tracking and extension of positive tracking periods

    Science.gov (United States)

    Hanan, Jay C.; Chao, Tien-Hsin; Moreels, Pierre

    2004-01-01

    Feature detectors have been considered for the role of supplying additional information to a neural network tracker. The feature detector focuses on areas of the image with significant information. Basically, if a picture says a thousand words, the feature detectors are looking for the key phrases (keypoints). These keypoints are rotationally invariant and may be matched across frames. Application of these advanced feature detectors to the neural network tracking system at JPL has promising potential. As part of an ongoing program, an advanced feature detector was tested for augmentation of a neural network based tracker. The advance feature detector extended tracking periods in test sequences including aircraft tracking, rover tracking, and simulated Martian landing. Future directions of research are also discussed.

  1. Kalman Filter Track Fits and Track Breakpoint Analysis

    CERN Document Server

    Astier, Pierre; Cousins, R D; Letessier-Selvon, A A; Popov, B A; Vinogradova, T G; Astier, Pierre; Cardini, Alessandro; Cousins, Robert D.; Letessier-Selvon, Antoine; Popov, Boris A.; Vinogradova, Tatiana

    2000-01-01

    We give an overview of track fitting using the Kalman filter method in the NOMAD detector at CERN, and emphasize how the wealth of by-product information can be used to analyze track breakpoints (discontinuities in track parameters caused by scattering, decay, etc.). After reviewing how this information has been previously exploited by others, we describe extensions which add power to breakpoint detection and characterization. We show how complete fits to the entire track, with breakpoint parameters added, can be easily obtained from the information from unbroken fits. Tests inspired by the Fisher F-test can then be used to judge breakpoints. Signed quantities (such as change in momentum at the breakpoint) can supplement unsigned quantities such as the various chisquares. We illustrate the method with electrons from real data, and with Monte Carlo simulations of pion decays.

  2. Visual object recognition and tracking

    Science.gov (United States)

    Chang, Chu-Yin (Inventor); English, James D. (Inventor); Tardella, Neil M. (Inventor)

    2010-01-01

    This invention describes a method for identifying and tracking an object from two-dimensional data pictorially representing said object by an object-tracking system through processing said two-dimensional data using at least one tracker-identifier belonging to the object-tracking system for providing an output signal containing: a) a type of the object, and/or b) a position or an orientation of the object in three-dimensions, and/or c) an articulation or a shape change of said object in said three dimensions.

  3. Tracking people through partial occlusions

    Institute of Scientific and Technical Information of China (English)

    LU Jian-guo; CAI An-ni

    2009-01-01

    This article presents a novel people-tracking approach to cope with partial occlusions caused by scene objects. Instead of predicting when and where the occlusions will occur, a part-based model is used to model the pixel distribution of the target body under occlusion. The subdivided patches corresponding to a template image will be tracked independently using Markov chain Monte Carlo (MCMC) method. A set of voting-based rules is established for the patch-tracking result to verify if the target is indeed located at the estimated position. Experiments show the effectiveness of the proposed method.

  4. Robust track fitting in the Belle II inner tracking detector

    Science.gov (United States)

    Nadler, Moritz; Frühwirth, Rudolf

    2012-12-01

    Track fitting in the new inner tracker of the Belle II experiment uses the GENFIT package. In the latter both a standard Kalman filter and a robust extension, the deterministic annealing filter (DAF), are implemented. This contribution presents the results of a simulation experiment which examines the performance of the DAF in the inner tracker, in terms of outlier detection ability and of the impact of different kinds of background on the quality of the fitted tracks.

  5. Tracks: A National Environmental Public Health Tracking Network Overview

    Centers for Disease Control (CDC) Podcasts

    2009-08-04

    In this podcast, Dr. Mike McGeehin, Director of CDC's Division of Environmental Hazards and Health Effects, provides an overview of the National Environmental Public Health Tracking Network. It highlights the Tracking Network's goal, how it will improve public health, its audience, and much more.  Created: 8/4/2009 by Centers for Disease Control and Prevention (CDC).   Date Released: 8/4/2009.

  6. Migration of implanted markers for image-guided lung tumor stereotactic ablative radiotherapy.

    Science.gov (United States)

    Hong, Julian C; Eclov, Neville C W; Yu, Yao; Rao, Aarti K; Dieterich, Sonja; Le, Quynh-Thu; Diehn, Maximilian; Sze, Daniel Y; Loo, Billy W; Kothary, Nishita; Maxim, Peter G

    2013-03-04

    The purpose of this study was to quantify postimplantation migration of percutaneously implanted cylindrical gold seeds ("seeds") and platinum endovascular embolization coils ("coils") for tumor tracking in pulmonary stereotactic ablative radiotherapy (SABR). We retrospectively analyzed the migration of markers in 32 consecutive patients with computed tomography scans postimplantation and at simulation. We implanted 147 markers (59 seeds, 88 coils) in or around 34 pulmonary tumors over 32 procedures, with one lesion implanted twice. Marker coordinates were rigidly aligned by minimizing fiducial registration error (FRE), the root mean square of the differences in marker locations for each tumor between scans. To also evaluate whether single markers were responsible for most migration, we aligned with and without the outlier causing the largest FRE increase per tumor. We applied the resultant transformation to all markers. We evaluated migration of individual markers and FRE of each group. Median scan interval was 8 days. Median individual marker migration was 1.28 mm (interquartile range [IQR] 0.78-2.63 mm). Median lesion FRE was 1.56 mm (IQR 0.92-2.95 mm). Outlier identification yielded 1.03 mm median migration (IQR 0.52-2.21 mm) and 1.97 mm median FRE (IQR 1.44-4.32 mm). Outliers caused a mean and median shift in the centroid of 1.22 and 0.80 mm (95th percentile 2.52 mm). Seeds and coils had no statistically significant difference. Univariate analysis suggested no correlation of migration with the number of markers, contact with the chest wall, or time elapsed. Marker migration between implantation and simulation is limited and unlikely to cause geometric miss during tracking.

  7. Automatic Thresholding for Frame-Repositioning Using External Tracking in PET Brain Imaging

    DEFF Research Database (Denmark)

    Olesen, Oline Vinter; Keller, Sune; Sibomana, Merence

    2010-01-01

    present an automated algorithm for dividing PET acquisitions into subframes based on the registered head motion to correct for intra-frame motion with the frame repositioning MC method. The method is tested on real patient data (five 11C-SB studies and five 11C-PIB studies) and compared with an image...

  8. External iliac artery injury secondary to indirect pressure wave effect from gunshot wound

    Institute of Scientific and Technical Information of China (English)

    Eugene Ng; Andrew MTL.Choong

    2016-01-01

    In patients presenting with gunshot wounds,a high clinical suspicion of injury to vasculature and viscera remote from the projectile track is paramount.We present a case of a 17 year old male who sustained a gunshot wound to his abdomen and subsequently developed a right external iliac artery contusion requiring surgery as an indirect effect of the pressure wave from the bullet.

  9. Adaptive Fuzzy Control for Nonlinear Fractional-Order Uncertain Systems with Unknown Uncertainties and External Disturbance

    OpenAIRE

    2015-01-01

    In this paper, the problem of robust control of nonlinear fractional-order systems in the presence of uncertainties and external disturbance is investigated. Fuzzy logic systems are used for estimating the unknown nonlinear functions. Based on the fractional Lyapunov direct method and some proposed Lemmas, an adaptive fuzzy controller is designed. The proposed method can guarantee all the signals in the closed-loop systems remain bounded and the tracking errors converge to an arbitrary small ...

  10. Low-wealth Entrepreneurs and Access to External Financing

    DEFF Research Database (Denmark)

    Frid, Casey J.; Wyman, David M.; Gartner, Bill

    2016-01-01

    endowments at the outset. Originality/value: -Unlike prior studies, the data used are not subject to survivor bias or an underrepresentation of self-employment. The statistical model jointly estimates acquisition of financing and the amount received. This resolves selection and censoring problems. Finally......Purpose: -The purpose of this paper is to explore the relationship between low-wealth business founders in the USA and external startup funding. Specifically, the authors test whether a founders’ low personal net worth is correlated with a lower probability of acquiring funding from outside sources......). The PSED II tracks business founders attempting to start ventures from 2005 to 2012. Findings: -Receipt of outside financing during business formation is largely determined by the business founder’s personal finances (controlling for human capital, venture type and industry, and whether money was sought...

  11. Modeling peer and external influence in online social networks

    CERN Document Server

    Piškorec, Matija; Miholić, Iva; Šmuc, Tomislav; Šikić, Mile

    2016-01-01

    Opinion polls mediated through a social network can give us, in addition to usual demographics data like age, gender and geographic location, a friendship structure between voters and the temporal dynamics of their activity during the voting process. Using a Facebook application we collected friendship relationships, demographics and votes of over ten thousand users on the referendum on the definition of marriage in Croatia held on 1st of December 2013. We also collected data on online news articles mentioning our application. Publication of these articles align closely with large peaks of voting activity, indicating that these external events have a crucial influence in engaging the voters. Also, existence of strongly connected friendship communities where majority of users vote during short time period, and the fact that majority of users in general tend to friend users that voted the same suggest that peer influence also has its role in engaging the voters. As we are not able to track activity of our users...

  12. Optimization approaches for planning external beam radiotherapy

    Science.gov (United States)

    Gozbasi, Halil Ozan

    Cancer begins when cells grow out of control as a result of damage to their DNA. These abnormal cells can invade healthy tissue and form tumors in various parts of the body. Chemotherapy, immunotherapy, surgery and radiotherapy are the most common treatment methods for cancer. According to American Cancer Society about half of the cancer patients receive a form of radiation therapy at some stage. External beam radiotherapy is delivered from outside the body and aimed at cancer cells to damage their DNA making them unable to divide and reproduce. The beams travel through the body and may damage nearby healthy tissue unless carefully planned. Therefore, the goal of treatment plan optimization is to find the best system parameters to deliver sufficient dose to target structures while avoiding damage to healthy tissue. This thesis investigates optimization approaches for two external beam radiation therapy techniques: Intensity-Modulated Radiation Therapy (IMRT) and Volumetric-Modulated Arc Therapy (VMAT). We develop automated treatment planning technology for IMRT that produces several high-quality treatment plans satisfying provided clinical requirements in a single invocation and without human guidance. A novel bi-criteria scoring based beam selection algorithm is part of the planning system and produces better plans compared to those produced using a well-known scoring-based algorithm. Our algorithm is very efficient and finds the beam configuration at least ten times faster than an exact integer programming approach. Solution times range from 2 minutes to 15 minutes which is clinically acceptable. With certain cancers, especially lung cancer, a patient's anatomy changes during treatment. These anatomical changes need to be considered in treatment planning. Fortunately, recent advances in imaging technology can provide multiple images of the treatment region taken at different points of the breathing cycle, and deformable image registration algorithms can

  13. Automatic respiration tracking for radiotherapy using optical 3D camera

    Science.gov (United States)

    Li, Tuotuo; Geng, Jason; Li, Shidong

    2013-03-01

    Rapid optical three-dimensional (O3D) imaging systems provide accurate digitized 3D surface data in real-time, with no patient contact nor radiation. The accurate 3D surface images offer crucial information in image-guided radiation therapy (IGRT) treatments for accurate patient repositioning and respiration management. However, applications of O3D imaging techniques to image-guided radiotherapy have been clinically challenged by body deformation, pathological and anatomical variations among individual patients, extremely high dimensionality of the 3D surface data, and irregular respiration motion. In existing clinical radiation therapy (RT) procedures target displacements are caused by (1) inter-fractional anatomy changes due to weight, swell, food/water intake; (2) intra-fractional variations from anatomy changes within any treatment session due to voluntary/involuntary physiologic processes (e.g. respiration, muscle relaxation); (3) patient setup misalignment in daily reposition due to user errors; and (4) changes of marker or positioning device, etc. Presently, viable solution is lacking for in-vivo tracking of target motion and anatomy changes during the beam-on time without exposing patient with additional ionized radiation or high magnet field. Current O3D-guided radiotherapy systems relay on selected points or areas in the 3D surface to track surface motion. The configuration of the marks or areas may change with time that makes it inconsistent in quantifying and interpreting the respiration patterns. To meet the challenge of performing real-time respiration tracking using O3D imaging technology in IGRT, we propose a new approach to automatic respiration motion analysis based on linear dimensionality reduction technique based on PCA (principle component analysis). Optical 3D image sequence is decomposed with principle component analysis into a limited number of independent (orthogonal) motion patterns (a low dimension eigen-space span by eigen-vectors). New

  14. Performance limitations in the tracking and regulation problem for discrete-time systems.

    Science.gov (United States)

    Jiang, Xiao-Wei; Guan, Zhi-Hong; Yuan, Fu-Shun; Zhang, Xian-He

    2014-03-01

    In this paper, the optimal tracking and regulation performance of discrete-time, multi-input multi-output, linear time-invariant systems is investigated. The control signal is influenced by the external disturbance, and the output feedback is subjected to an additive white Gaussian noise (AWGN) corruption. The tracking error with channel input power constraint and the output regulation with control energy constraint are adopted as the measure of tracking and regulation performance respectively, which can be obtained by searching through all stabilizing two-parameter controllers. Both results demonstrate that the performance is closely related to locations and directions of the nonminimum phase zeros, unstable poles of the plant and may be badly degraded by external disturbance and AWGN.

  15. On-Line Tracking Controller for Brushless DC Motor Drives Using Artificial Neural Networks

    Science.gov (United States)

    Rubaai, Ahmed

    1996-01-01

    A real-time control architecture is developed for time-varying nonlinear brushless dc motors operating in a high performance drives environment. The developed control architecture possesses the capabilities of simultaneous on-line identification and control. The dynamics of the motor are modeled on-line and controlled using an artificial neural network, as the system runs. The control architecture combines the experience and dependability of adaptive tracking systems with potential and promise of the neural computing technology. The sensitivity of real-time controller to parametric changes that occur during training is investigated. Such changes are usually manifested by rapid changes in the load of the brushless motor drives. This sudden change in the external load is simulated for the sigmoidal and sinusoidal reference tracks. The ability of the neuro-controller to maintain reasonable tracking accuracy in the presence of external noise is also verified for a number of desired reference trajectories.

  16. Simulation of Telescope Detectivity for Geo Survey and Tracking

    Science.gov (United States)

    Richard, P.

    2014-09-01

    As the number of space debris on Earths Orbit increases steadily, the need to survey, track and catalogue them becomes of key importance. In this context, CNES has been using the TAROT Telescopes (Rapid Telescopes for Transient Objects owned and operated by CNRS) for several years to conduct studies about space surveillance and tracking. Today, two testbeds of services using the TAROT telescopes are running every night: one for GEO situational awareness and the second for debris tracking. Additionally to the CNES research activity on space surveillance and tracking domain, an operational collision avoidance service for LEO and GEO satellites is in place at CNES for several years. This service named CAESAR (Conjunction Analysis and Evaluation: Alerts and Recommendations) is used by CNES as well as by external customers. As the optical debris tracking testbed based on TAROT telescopes is the first step toward an operational provider of GEO measures that could be used by CAESAR, simulations have been done to help choosing the sites and types of telescopes that could be added in the GEO survey and debris tracking telescope network. One of the distinctive characteristics of the optical observation of space debris compared to traditional astronomic observation is the need to observe objects at low elevations. The two mains reasons for this are the need to observe the GEO belt from non-equatorial sites and the need to observe debris at longitudes far from the telescope longitude. This paper presents the results of simulations of the detectivity for GEO debris of various telescopes and sites, based on models of the GEO belt, the atmosphere and the instruments. One of the conclusions is that clever detection of faint streaks and spread sources by image processing is one of the major keys to improve the detection of debris on the GEO belt.

  17. Development of a tracking method for augmented reality applied to nuclear plant maintenance work

    Energy Technology Data Exchange (ETDEWEB)

    Shimoda, Hiroshi; Maeshima, Masayuki; Nakai, Toshinori; Bian, Zhiqiang; Ishii, Hirotake; Yoshikawa, Hidekazu [Kyoto University, Kyoto (Japan)

    2005-11-15

    In this paper, a plant maintenance support method is described, which employs the state-of-the-art information technology, Augmented Reality (AR), in order to improve efficiency of NPP maintenance work and to prevent from human error. Although AR has a great possibility to support various works in real world, it is difficult to apply it to actual work support because the tracking method is the bottleneck for the practical use. In this study, a bar code marker tracking method is proposed to apply AR system for a maintenance work support in NPP field. The proposed method calculates the users position and orientation in real time by two long markers, which are captured by the user-mounted camera. The markers can be easily pasted on the pipes in plant field, and they can be easily recognized in long distance in order to reduce the number of pasted markers in the work field. Experiments were conducted in a laboratory and plant field to evaluate the proposed method. The results show that (1) fast and stable tracking can be realized, (2) position error in camera view is less than 1%, which is almost perfect under the limitation of camera resolution, and (3) it is relatively difficult to catch two markers in one camera view especially in short distance.

  18. GARFOGIS_DATA_TRACKING.xlsm

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This spreadsheet is the central tracking document and inventory of "official" GIS datasets in development, published, or archived at the Greater Atlantic Regional...

  19. Dynamic Ocean Track System Plus -

    Data.gov (United States)

    Department of Transportation — Dynamic Ocean Track System Plus (DOTS Plus) is a planning tool implemented at the ZOA, ZAN, and ZNY ARTCCs. It is utilized by Traffic Management Unit (TMU) personnel...

  20. ACED Federal Grant Contractor Tracking

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Dataset includes grant, project, and contractor awarded which are tracked for ensuring Davis-Bacon Act compliance where applicable. The 1931 Davis-Bacon Act...

  1. Neural Markers of Responsiveness to the Environment in Human Sleep

    DEFF Research Database (Denmark)

    Andrillon, Thomas; Poulsen, Andreas Trier; Hansen, Lars Kai

    2016-01-01

    could be related to modulation in sleep depth. InREMsleep, however, this relationship was reversed.Wetherefore propose that, in REM sleep, endogenously generated processes compete with the processing of external input. Sleep can thus be seen as a self-regulated process in which external information can......Sleep is characterized by a loss of behavioral responsiveness. However, recent research has shown that the sleeping brain is not completely disconnected from its environment. How neural activity constrains the ability to process sensory information while asleep is yet unclear. Here, we instructed...... by Lempel-Ziv complexity (LZc), a measure shown to track arousal in sleep and anesthesia. Neural activity related to the semantic content of stimuli was conserved in light non-rapid eye movement (NREM) sleep. However, these processes were suppressed in deep NREM sleep and, importantly, also in REM sleep...

  2. Development of Solar Tracking System Using Imc-Pid Controller

    Directory of Open Access Journals (Sweden)

    Bamigboye O. Oladayo

    2016-06-01

    Full Text Available In the past, solar cells are hooked with fixed elevating angles, and it does not track the sun. Therefore the efficiency of the power generation is low. A solar panel receives the most sunlight when it is perpendicular to the sun’s rays, but the sunlight direction changes regularly with changing seasons and weather. There is therefore the need to track the solar panel to increase its efficiency. The stability and improved speed of response can only be achieved with appropriate controller to take care of external disturbances and design uncertainty associated with a conventional controller. The IMC controller would be used to allow good tracking ability and good load disturbance rejection Unconventional controller like fuzzy logic can be used to tune the PID controller andthe result compared with using a conventional controller like ZN. The internal model control based proportional integral derivative design procedure can be implemented in industrial processes using existing proportional integral derivative control equipment. Modeling of a dual axis solar tracker. An IMC-PID controller was developed for a dual axis solar tracker. The result of this work showed that the IMC-PID controller provided an efficient and commendable improvement in the relative stability, disturbance attenuation, set point tracking and an improved speed of response for the system

  3. Low frame rate video target localization and tracking testbed

    Science.gov (United States)

    Pang, Yu; Shen, Dan; Chen, Genshe; Liang, Pengpeng; Pham, Khanh; Blasch, Erik; Wang, Zhonghai; Ling, Haibin

    2013-05-01

    Traditional tracking frameworks are challenged by low video frame rate scenarios, because the appearances and locations of the target may change considerably in consecutive frames. Our paper presents a saliency-based temporal association dependency (STAD) framework to deal with such a low frame rate scenario and demonstrate good results in our robot testbed. We first use median filter to create a background of the scene, then apply background subtraction to every new frame to decide the rough position of the target. With the help of the markers on the robots, we use a gradient voting algorithm to detect the high responses of the directions of the robots. Finally, a template matching with branch pruning is used to obtain the finer estimation of the pose of the robots. To make the tracking-by-detection framework stable, we further introduce the temporal constraints using a previously detected result as well as an association technique. Our experiments show that our method can achieve a very stable tracking result and outperforms some state-of-the-art trackers such as Meanshift, Online-AdaBoosting, Mulitple-Instance-Learning, Tracking-Learning-Detection etc. Also. we demonstrate that our algorithm provides near real-time solutions given the low frame rate requirement.

  4. Automatic colonic lesion detection and tracking in endoscopic videos

    Science.gov (United States)

    Li, Wenjing; Gustafsson, Ulf; A-Rahim, Yoursif

    2011-03-01

    The biology of colorectal cancer offers an opportunity for both early detection and prevention. Compared with other imaging modalities, optical colonoscopy is the procedure of choice for simultaneous detection and removal of colonic polyps. Computer assisted screening makes it possible to assist physicians and potentially improve the accuracy of the diagnostic decision during the exam. This paper presents an unsupervised method to detect and track colonic lesions in endoscopic videos. The aim of the lesion screening and tracking is to facilitate detection of polyps and abnormal mucosa in real time as the physician is performing the procedure. For colonic lesion detection, the conventional marker controlled watershed based segmentation is used to segment the colonic lesions, followed by an adaptive ellipse fitting strategy to further validate the shape. For colonic lesion tracking, a mean shift tracker with background modeling is used to track the target region from the detection phase. The approach has been tested on colonoscopy videos acquired during regular colonoscopic procedures and demonstrated promising results.

  5. Kalman Orbit Optimized Loop Tracking

    Science.gov (United States)

    Young, Lawrence E.; Meehan, Thomas K.

    2011-01-01

    Under certain conditions of low signal power and/or high noise, there is insufficient signal to noise ratio (SNR) to close tracking loops with individual signals on orbiting Global Navigation Satellite System (GNSS) receivers. In addition, the processing power available from flight computers is not great enough to implement a conventional ultra-tight coupling tracking loop. This work provides a method to track GNSS signals at very low SNR without the penalty of requiring very high processor throughput to calculate the loop parameters. The Kalman Orbit-Optimized Loop (KOOL) tracking approach constitutes a filter with a dynamic model and using the aggregate of information from all tracked GNSS signals to close the tracking loop for each signal. For applications where there is not a good dynamic model, such as very low orbits where atmospheric drag models may not be adequate to achieve the required accuracy, aiding from an IMU (inertial measurement unit) or other sensor will be added. The KOOL approach is based on research JPL has done to allow signal recovery from weak and scintillating signals observed during the use of GPS signals for limb sounding of the Earth s atmosphere. That approach uses the onboard PVT (position, velocity, time) solution to generate predictions for the range, range rate, and acceleration of the low-SNR signal. The low- SNR signal data are captured by a directed open loop. KOOL builds on the previous open loop tracking by including feedback and observable generation from the weak-signal channels so that the MSR receiver will continue to track and provide PVT, range, and Doppler data, even when all channels have low SNR.

  6. Precision laser automatic tracking system.

    Science.gov (United States)

    Lucy, R F; Peters, C J; McGann, E J; Lang, K T

    1966-04-01

    A precision laser tracker has been constructed and tested that is capable of tracking a low-acceleration target to an accuracy of about 25 microrad root mean square. In tracking high-acceleration targets, the error is directly proportional to the angular acceleration. For an angular acceleration of 0.6 rad/sec(2), the measured tracking error was about 0.1 mrad. The basic components in this tracker, similar in configuration to a heliostat, are a laser and an image dissector, which are mounted on a stationary frame, and a servocontrolled tracking mirror. The daytime sensitivity of this system is approximately 3 x 10(-10) W/m(2); the ultimate nighttime sensitivity is approximately 3 x 10(-14) W/m(2). Experimental tests were performed to evaluate both dynamic characteristics of this system and the system sensitivity. Dynamic performance of the system was obtained, using a small rocket covered with retroreflective material launched at an acceleration of about 13 g at a point 204 m from the tracker. The daytime sensitivity of the system was checked, using an efficient retroreflector mounted on a light aircraft. This aircraft was tracked out to a maximum range of 15 km, which checked the daytime sensitivity of the system measured by other means. The system also has been used to track passively stars and the Echo I satellite. Also, the system tracked passively a +7.5 magnitude star, and the signal-to-noise ratio in this experiment indicates that it should be possible to track a + 12.5 magnitude star.

  7. Sliding mode tracking control for miniature unmanned helicopters

    Directory of Open Access Journals (Sweden)

    Bin Xian

    2015-02-01

    Full Text Available A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter’s dynamic model is divided into two subsystems, such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles’ dynamic effects and external disturbances. The global asymptotic stability (GAS of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportional-integral-derivative (PID and linear-quadratic regulator (LQR cascaded controller in the presence of wind gust disturbances.

  8. Sliding mode tracking control for miniature unmanned helicopters

    Institute of Scientific and Technical Information of China (English)

    Xian Bin; Guo Jianchuan; Zhang Yao; Zhao Bo

    2015-01-01

    A sliding mode control design for a miniature unmanned helicopter is presented. The control objective is to let the helicopter track some predefined velocity and yaw trajectories. A new sliding mode control design method is developed based on a linearized dynamic model. In order to facilitate the control design, the helicopter’s dynamic model is divided into two subsystems, such as the longitudinal-lateral and the heading-heave subsystem. The proposed controller employs sliding mode control technique to compensate for the immeasurable flapping angles’ dynamic effects and external disturbances. The global asymptotic stability (GAS) of the closed-loop system is proved by the Lyapunov based stability analysis. Numerical simulations demonstrate that the proposed controller can achieve superior tracking performance compared with the proportional-integral-derivative (PID) and linear-quadratic regulator (LQR) cascaded controller in the presence of wind gust disturbances.

  9. Drone Identification and Tracking in Denmark

    DEFF Research Database (Denmark)

    Jensen, Kjeld; Skriver, Martin; Schultz, Ulrik Pagh

    for experts to build upon this work. Based on input from the stakeholders a system design for drone identification and tracking has been proposed. The system design supports communication between thedroneandtheUTMviaeitheralocalbeaconsignaloraradionetworkinfrastructure. The required drone functionality may....... Therecordedflights did provide valuable knowledge concerning the pilot interaction with the DroneID device and helped testing the hardware and software. Data received by the UTM has been analysed and compared with detailed logs provided by the pilots. Some issues concerning technical design and usability were...... discovered, and the proposed system design has been updated accordingly. It is concluded that to the extent tested in this work it is feasible to efficiently identify and track drones fitted with the external DroneID device by a UTM service. The project partners have agreed to continue this work: A new version...

  10. Real-time tumor tracking with an artificial neural networks-based method: a feasibility study.

    Science.gov (United States)

    Seregni, Matteo; Pella, Andrea; Riboldi, Marco; Orecchia, Roberto; Cerveri, Pietro; Baroni, Guido

    2013-01-01

    The purpose of this study was to develop and assess the performance of a tumor tracking method designed for application in radiation therapy. This motion compensation strategy is currently applied clinically only in conventional photon radiotherapy but not in particle therapy, as greater accuracy in dose delivery is required. We proposed a tracking method that exploits artificial neural networks to estimate the internal tumor trajectory as a function of external surrogate signals. The developed algorithm was tested by means of a retrospective clinical data analysis in 20 patients, who were treated with state of the art infra-red motion tracking for photon radiotherapy, which is used as a benchmark. Integration into a hardware platform for motion tracking in particle therapy was performed and then tested on a moving phantom, specifically developed for this purpose. Clinical data show that a median tracking error reduction up to 0.7 mm can be achieved with respect to state of the art technologies. The phantom study demonstrates that a real-time tumor position estimation is feasible when the external signals are acquired at 60 Hz. The results of this work show that neural networks can be considered a valuable tool for the implementation of high accuracy real-time tumor tracking methodologies.

  11. ANALYSIS OF EXTERNAL FACTORS AFFECTING THE PRICING

    Directory of Open Access Journals (Sweden)

    Irina A. Kiseleva

    2013-01-01

    Full Text Available The external factors influencing the process of formation of tariffs of commercial services are considered in the article. External environment is known to be very diverse and changeable. Currently, pricing has become one of the key processes of strategic development of a company. Pricing in the service sector, in turn, is highly susceptible to changes in the external environment. Its components directly or indirectly affect the market of services, changing it adopted economic processes. As a rule, firms providing services can’t influence the changes in external factors. However, the service market is very flexible, which enables businesses to reshape pricing strategy, to adapt it to the new environment.

  12. Consensus Tracking of Heterogeneous Discrete-Time Networked Multiagent Systems Based on the Networked Predictive Control Scheme.

    Science.gov (United States)

    Wei, Yuxin; Liu, Guo-Ping

    2017-05-16

    This paper studies the problem of consensus tracking for heterogeneous discrete-time networked multiagent systems (NMASs) with network-induced communication delay. By introducing the networked predictive control scheme, novel consensus tracking protocols are designed to ensure that states of the NMASs follow the external reference signal. One of the agents is defined as the leader agent, all the other agents are defined as the followers, and the external reference signal is always known by the leader agent, both cases where the external reference signal is available and unavailable to the follower agents are discussed in this paper. The necessary and sufficient conditions for the novel consensus tracking protocols are proposed based on algebraic and graph theory. Numerical examples are given to validate the theoretical results.

  13. [Tumor markers for hepatocellular carcinoma].

    Science.gov (United States)

    Tateishi, Ryosuke; Enooku, Kenichiro; Shiina, Shuichiro; Koike, Kazuhiko

    2012-05-01

    Three tumor markers for hepatocellular carcinoma (HCC) are available in Japan: alpha-fetoprotein (AFP), protein induced by vitamin K absence or antagonists-II (PIVKA-II), and Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3). Although AFP has drawbacks in its specificity, it is widely utilized in treatment evaluation and prognosis prediction. PIVKA-II is a unique marker that does not correlate with AFP value and can predict microvascular invasion. AFP-L3 is a highly specific marker and strong predictor of poor prognosis. These three markers are indispensable in every aspect of clinical practice of hepatocellular carcinoma including surveillance, diagnosis, treatment evaluation, and prognosis prediction.

  14. Motion management during IMAT treatment of mobile lung tumors—A comparison of MLC tracking and gated delivery

    Science.gov (United States)

    Falk, Marianne; Pommer, Tobias; Keall, Paul; Korreman, Stine; Persson, Gitte; Poulsen, Per; Munck af Rosenschöld, Per

    2014-01-01

    Purpose: To compare real-time dynamic multileaf collimator (MLC) tracking, respiratory amplitude and phase gating, and no compensation for intrafraction motion management during intensity modulated arc therapy (IMAT). Methods: Motion management with MLC tracking and gating was evaluated for four lung cancer patients. The IMAT plans were delivered to a dosimetric phantom mounted onto a 3D motion phantom performing patient-specific lung tumor motion. The MLC tracking system was guided by an optical system that used stereoscopic infrared (IR) cameras and five spherical reflecting markers attached to the dosimetric phantom. The gated delivery used a duty cycle of 35% and collected position data using an IR camera and two reflecting markers attached to a marker block. Results: The average gamma index failure rate (2% and 2 mm criteria) was delivery time. In a clinical setting, the optical monitoring of the patients breathing would have to be correlated to the internal movements of the tumor. PMID:25281946

  15. Population Structure in Naegleria fowleri as Revealed by Microsatellite Markers.

    Science.gov (United States)

    Coupat-Goutaland, Bénédicte; Régoudis, Estelle; Besseyrias, Matthieu; Mularoni, Angélique; Binet, Marie; Herbelin, Pascaline; Pélandakis, Michel

    2016-01-01

    Naegleria sp. is a free living amoeba belonging to the Heterolobosea class. Over 40 species of Naegleria were identified and recovered worldwide in different habitats such as swimming pools, freshwater lakes, soil or dust. Among them, N. fowleri, is a human pathogen responsible for primary amoeboic meningoencephalitis (PAM). Around 300 cases were reported in 40 years worldwide but PAM is a fatal disease of the central nervous system with only 5% survival of infected patients. Since both pathogenic and non pathogenic species were encountered in the environment, detection and dispersal mode are crucial points in the fight against this pathogenic agent. Previous studies on identification and genotyping of N. fowleri strains were focused on RAPD analysis and on ITS sequencing and identified 5 variants: euro-american, south pacific, widespread, cattenom and chooz. Microsatellites are powerful markers in population genetics with broad spectrum of applications (such as paternity test, fingerprinting, genetic mapping or genetic structure analysis). They are characterized by a high degree of length polymorphism. The aim of this study was to genotype N. fowleri strains using microsatellites markers in order to track this population and to better understand its evolution. Six microsatellite loci and 47 strains from different geographical origins were used for this analysis. The microsatellite markers revealed a level of discrimination higher than any other marker used until now, enabling the identification of seven genetic groups, included in the five main genetic groups based on the previous RAPD and ITS analyses. This analysis also allowed us to go further in identifying private alleles highlighting intra-group variability. A better identification of the N. fowleri isolates could be done with this type of analysis and could allow a better tracking of the clinical and environmental N. fowleri strains.

  16. Population Structure in Naegleria fowleri as Revealed by Microsatellite Markers.

    Directory of Open Access Journals (Sweden)

    Bénédicte Coupat-Goutaland

    Full Text Available Naegleria sp. is a free living amoeba belonging to the Heterolobosea class. Over 40 species of Naegleria were identified and recovered worldwide in different habitats such as swimming pools, freshwater lakes, soil or dust. Among them, N. fowleri, is a human pathogen responsible for primary amoeboic meningoencephalitis (PAM. Around 300 cases were reported in 40 years worldwide but PAM is a fatal disease of the central nervous system with only 5% survival of infected patients. Since both pathogenic and non pathogenic species were encountered in the environment, detection and dispersal mode are crucial points in the fight against this pathogenic agent. Previous studies on identification and genotyping of N. fowleri strains were focused on RAPD analysis and on ITS sequencing and identified 5 variants: euro-american, south pacific, widespread, cattenom and chooz. Microsatellites are powerful markers in population genetics with broad spectrum of applications (such as paternity test, fingerprinting, genetic mapping or genetic structure analysis. They are characterized by a high degree of length polymorphism. The aim of this study was to genotype N. fowleri strains using microsatellites markers in order to track this population and to better understand its evolution. Six microsatellite loci and 47 strains from different geographical origins were used for this analysis. The microsatellite markers revealed a level of discrimination higher than any other marker used until now, enabling the identification of seven genetic groups, included in the five main genetic groups based on the previous RAPD and ITS analyses. This analysis also allowed us to go further in identifying private alleles highlighting intra-group variability. A better identification of the N. fowleri isolates could be done with this type of analysis and could allow a better tracking of the clinical and environmental N. fowleri strains.

  17. Serotonin, neural markers, and memory

    OpenAIRE

    Alfredo eMeneses

    2015-01-01

    Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The i...

  18. Measurements of radon in dwellings with CR-39 track detectors

    DEFF Research Database (Denmark)

    Majborn, Benny

    1986-01-01

    A passive integrating dosemeter has been designed for measuring natural radiation in dwellings. The dosemeter contains one or two CR-39 track detectors to measure radon and three thermoluminescence dosemeters to measure external radiation. The dosemeter was investigated in a pilot study in 1983....../84, and it is now used in a nationwide survey of natural radiation in Danish dwellings. The characteristics of the dosemeter with respect to radon measurements are presented, and the radon monitoring results obtained in the pilot study are summarized...

  19. Control of External Kink Instability

    Science.gov (United States)

    Navratil, Gerald

    2004-11-01

    A fundamental pressure and current limiting phenomenon in magnetically confined plasmas for fusion energy is the long wavelength ideal-MHD kink mode. These modes have been extensively studied in tokamak and reversed field pinch (RFP) devices. They are characterized by significant amplitude on the boundary of the confined plasma and can therefore be controlled by manipulation of the external boundary conditions. In the past ten years, the theoretically predicted stabilizing effect of a nearby conducting wall has been documented in experiments, which opens the possibility of a significant increase in maximum stable plasma pressure. While these modes are predicted to remain unstable when the stabilizing wall is resistive, their growth rates are greatly reduced from the hydrodynamic time scale to the time scale of magnetic diffusion through the resistive wall. These resistive wall slowed kink modes have been identified as limiting phenomena in tokamak (DIII-D, PBX-M, HBT-EP, JT-60U, JET, NSTX) and RFP (HBTX, Extrap, T2R) devices. The theoretical prediction of stabilization to nearly the ideal wall pressure limit by toroidal plasma rotation and/or active feedback control using coils has recently been realized experimentally. Sustained, stable operation at double the no-wall pressure limit has been achieved. Discovery of the phenomenon of resonant field amplification by marginally stable kink modes and its role in the momentum balance of rotationally stabilized plasmas has emerged as a key feature. A theoretical framework, based on an extension of the very successful treatment of the n=0 axisymmetric mode developed in the early 1990's, to understand the stabilization mechanisms and model the performance of active feedback control systems is now established. This allows design of kink control systems for burning plasma experiments like ITER.

  20. TrackNTrace: A simple and extendable open-source framework for developing single-molecule localization and tracking algorithms.

    Science.gov (United States)

    Stein, Simon Christoph; Thiart, Jan

    2016-11-25

    Super-resolution localization microscopy and single particle tracking are important tools for fluorescence microscopy. Both rely on detecting, and tracking, a large number of fluorescent markers using increasingly sophisticated computer algorithms. However, this rise in complexity makes it difficult to fine-tune parameters and detect inconsistencies, improve existing routines, or develop new approaches founded on established principles. We present an open-source MATLAB framework for single molecule localization, tracking and super-resolution applications. The purpose of this software is to facilitate the development, distribution, and comparison of methods in the community by providing a unique, easily extendable plugin-based system and combining it with a novel visualization system. This graphical interface incorporates possibilities for quick inspection of localization and tracking results, giving direct feedback of the quality achieved with the chosen algorithms and parameter values, as well as possible sources for errors. This is of great importance in practical applications and even more so when developing new techniques. The plugin system greatly simplifies the development of new methods as well as adapting and tailoring routines towards any research problem's individual requirements. We demonstrate its high speed and accuracy with plugins implementing state-of-the-art algorithms and show two biological applications.