Long-term scale adaptive tracking with kernel correlation filters
NASA Astrophysics Data System (ADS)
Wang, Yueren; Zhang, Hong; Zhang, Lei; Yang, Yifan; Sun, Mingui
2018-04-01
Object tracking in video sequences has broad applications in both military and civilian domains. However, as the length of input video sequence increases, a number of problems arise, such as severe object occlusion, object appearance variation, and object out-of-view (some portion or the entire object leaves the image space). To deal with these problems and identify the object being tracked from cluttered background, we present a robust appearance model using Speeded Up Robust Features (SURF) and advanced integrated features consisting of the Felzenszwalb's Histogram of Oriented Gradients (FHOG) and color attributes. Since re-detection is essential in long-term tracking, we develop an effective object re-detection strategy based on moving area detection. We employ the popular kernel correlation filters in our algorithm design, which facilitates high-speed object tracking. Our evaluation using the CVPR2013 Object Tracking Benchmark (OTB2013) dataset illustrates that the proposed algorithm outperforms reference state-of-the-art trackers in various challenging scenarios.
A-Track: Detecting Moving Objects in FITS images
NASA Astrophysics Data System (ADS)
Atay, T.; Kaplan, M.; Kilic, Y.; Karapinar, N.
2017-04-01
A-Track is a fast, open-source, cross-platform pipeline for detecting moving objects (asteroids and comets) in sequential telescope images in FITS format. The moving objects are detected using a modified line detection algorithm.
Cross-Modal Attention Effects in the Vestibular Cortex during Attentive Tracking of Moving Objects.
Frank, Sebastian M; Sun, Liwei; Forster, Lisa; Tse, Peter U; Greenlee, Mark W
2016-12-14
The midposterior fundus of the Sylvian fissure in the human brain is central to the cortical processing of vestibular cues. At least two vestibular areas are located at this site: the parietoinsular vestibular cortex (PIVC) and the posterior insular cortex (PIC). It is now well established that activity in sensory systems is subject to cross-modal attention effects. Attending to a stimulus in one sensory modality enhances activity in the corresponding cortical sensory system, but simultaneously suppresses activity in other sensory systems. Here, we wanted to probe whether such cross-modal attention effects also target the vestibular system. To this end, we used a visual multiple-object tracking task. By parametrically varying the number of tracked targets, we could measure the effect of attentional load on the PIVC and the PIC while holding the perceptual load constant. Participants performed the tracking task during functional magnetic resonance imaging. Results show that, compared with passive viewing of object motion, activity during object tracking was suppressed in the PIVC and enhanced in the PIC. Greater attentional load, induced by increasing the number of tracked targets, was associated with a corresponding increase in the suppression of activity in the PIVC. Activity in the anterior part of the PIC decreased with increasing load, whereas load effects were absent in the posterior PIC. Results of a control experiment show that attention-induced suppression in the PIVC is stronger than any suppression evoked by the visual stimulus per se. Overall, our results suggest that attention has a cross-modal modulatory effect on the vestibular cortex during visual object tracking. In this study we investigate cross-modal attention effects in the human vestibular cortex. We applied the visual multiple-object tracking task because it is known to evoke attentional load effects on neural activity in visual motion-processing and attention-processing areas. Here we demonstrate a load-dependent effect of attention on the activation in the vestibular cortex, despite constant visual motion stimulation. We find that activity in the parietoinsular vestibular cortex is more strongly suppressed the greater the attentional load on the visual tracking task. These findings suggest cross-modal attentional modulation in the vestibular cortex. Copyright © 2016 the authors 0270-6474/16/3612720-09$15.00/0.
Real-time Human Activity Recognition
NASA Astrophysics Data System (ADS)
Albukhary, N.; Mustafah, Y. M.
2017-11-01
The traditional Closed-circuit Television (CCTV) system requires human to monitor the CCTV for 24/7 which is inefficient and costly. Therefore, there’s a need for a system which can recognize human activity effectively in real-time. This paper concentrates on recognizing simple activity such as walking, running, sitting, standing and landing by using image processing techniques. Firstly, object detection is done by using background subtraction to detect moving object. Then, object tracking and object classification are constructed so that different person can be differentiated by using feature detection. Geometrical attributes of tracked object, which are centroid and aspect ratio of identified tracked are manipulated so that simple activity can be detected.
Visual attention is required for multiple object tracking.
Tran, Annie; Hoffman, James E
2016-12-01
In the multiple object tracking task, participants attempt to keep track of a moving set of target objects embedded in an identical set of moving distractors. Depending on several display parameters, observers are usually only able to accurately track 3 to 4 objects. Various proposals attribute this limit to a fixed number of discrete indexes (Pylyshyn, 1989), limits in visual attention (Cavanagh & Alvarez, 2005), or "architectural limits" in visual cortical areas (Franconeri, 2013). The present set of experiments examined the specific role of visual attention in tracking using a dual-task methodology in which participants tracked objects while identifying letter probes appearing on the tracked objects and distractors. As predicted by the visual attention model, probe identification was faster and/or more accurate when probes appeared on tracked objects. This was the case even when probes were more than twice as likely to appear on distractors suggesting that some minimum amount of attention is required to maintain accurate tracking performance. When the need to protect tracking accuracy was relaxed, participants were able to allocate more attention to distractors when probes were likely to appear there but only at the expense of large reductions in tracking accuracy. A final experiment showed that people attend to tracked objects even when letters appearing on them are task-irrelevant, suggesting that allocation of attention to tracked objects is an obligatory process. These results support the claim that visual attention is required for tracking objects. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Assessing Multiple Object Tracking in Young Children Using a Game
ERIC Educational Resources Information Center
Ryokai, Kimiko; Farzin, Faraz; Kaltman, Eric; Niemeyer, Greg
2013-01-01
Visual tracking of multiple objects in a complex scene is a critical survival skill. When we attempt to safely cross a busy street, follow a ball's position during a sporting event, or monitor children in a busy playground, we rely on our brain's capacity to selectively attend to and track the position of specific objects in a dynamic scene. This…
Real-time reliability measure-driven multi-hypothesis tracking using 2D and 3D features
NASA Astrophysics Data System (ADS)
Zúñiga, Marcos D.; Brémond, François; Thonnat, Monique
2011-12-01
We propose a new multi-target tracking approach, which is able to reliably track multiple objects even with poor segmentation results due to noisy environments. The approach takes advantage of a new dual object model combining 2D and 3D features through reliability measures. In order to obtain these 3D features, a new classifier associates an object class label to each moving region (e.g. person, vehicle), a parallelepiped model and visual reliability measures of its attributes. These reliability measures allow to properly weight the contribution of noisy, erroneous or false data in order to better maintain the integrity of the object dynamics model. Then, a new multi-target tracking algorithm uses these object descriptions to generate tracking hypotheses about the objects moving in the scene. This tracking approach is able to manage many-to-many visual target correspondences. For achieving this characteristic, the algorithm takes advantage of 3D models for merging dissociated visual evidence (moving regions) potentially corresponding to the same real object, according to previously obtained information. The tracking approach has been validated using video surveillance benchmarks publicly accessible. The obtained performance is real time and the results are competitive compared with other tracking algorithms, with minimal (or null) reconfiguration effort between different videos.
"OZONE SOURCE APPORTIONMENT IN CMAQ'
Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental tran...
Dynamic Trajectory Extraction from Stereo Vision Using Fuzzy Clustering
NASA Astrophysics Data System (ADS)
Onishi, Masaki; Yoda, Ikushi
In recent years, many human tracking researches have been proposed in order to analyze human dynamic trajectory. These researches are general technology applicable to various fields, such as customer purchase analysis in a shopping environment and safety control in a (railroad) crossing. In this paper, we present a new approach for tracking human positions by stereo image. We use the framework of two-stepped clustering with k-means method and fuzzy clustering to detect human regions. In the initial clustering, k-means method makes middle clusters from objective features extracted by stereo vision at high speed. In the last clustering, c-means fuzzy method cluster middle clusters based on attributes into human regions. Our proposed method can be correctly clustered by expressing ambiguity using fuzzy clustering, even when many people are close to each other. The validity of our technique was evaluated with the experiment of trajectories extraction of doctors and nurses in an emergency room of a hospital.
ERIC Educational Resources Information Center
Rodriguez, Christina M.; Cook, Anne E.; Jedrziewski, Chezlie T.
2012-01-01
Objective: Researchers in the child maltreatment field have traditionally relied on explicit self-reports to study factors that may exacerbate physical child abuse risk. The current investigation evaluated an implicit analog task utilizing eye tracking technology to assess both parental attributions of child misbehavior and empathy. Method: Based…
NASA Astrophysics Data System (ADS)
Pan, Min-Chun; Liao, Shiu-Wei; Chiu, Chun-Chin
2007-02-01
The waveform-reconstruction schemes of order tracking (OT) such as the Gabor and the Vold-Kalman filtering (VKF) techniques can extract specific order and/or spectral components in addition to characterizing the processed signal in rpm-frequency domain. The study first improves the Gabor OT (GOT) technique to handle the order-crossing problem, and then objectively compares the features of the improved GOT scheme and the angular-displacement VKF OT technique. It is numerically observed the improved method performs less accurately than the VKF_OT scheme at the crossing occurrences, but without end effect in the reconstructed waveform. As OT is not exact science, it may well be that the decrease in computation time can justify the reduced accuracy. The characterisation and discrimination of riding noise with crossing orders emitted by an electrical scooter are conducted as an example of the application.
Defante, Adrian P; Vreeland, Wyatt N; Benkstein, Kurt D; Ripple, Dean C
2018-05-01
Nanoparticle tracking analysis (NTA) obtains particle size by analysis of particle diffusion through a time series of micrographs and particle count by a count of imaged particles. The number of observed particles imaged is controlled by the scattering cross-section of the particles and by camera settings such as sensitivity and shutter speed. Appropriate camera settings are defined as those that image, track, and analyze a sufficient number of particles for statistical repeatability. Here, we test if image attributes, features captured within the image itself, can provide measurable guidelines to assess the accuracy for particle size and count measurements using NTA. The results show that particle sizing is a robust process independent of image attributes for model systems. However, particle count is sensitive to camera settings. Using open-source software analysis, it was found that a median pixel area, 4 pixels 2 , results in a particle concentration within 20% of the expected value. The distribution of these illuminated pixel areas can also provide clues about the polydispersity of particle solutions prior to using a particle tracking analysis. Using the median pixel area serves as an operator-independent means to assess the quality of the NTA measurement for count. Published by Elsevier Inc.
Security Applications Of Computer Motion Detection
NASA Astrophysics Data System (ADS)
Bernat, Andrew P.; Nelan, Joseph; Riter, Stephen; Frankel, Harry
1987-05-01
An important area of application of computer vision is the detection of human motion in security systems. This paper describes the development of a computer vision system which can detect and track human movement across the international border between the United States and Mexico. Because of the wide range of environmental conditions, this application represents a stringent test of computer vision algorithms for motion detection and object identification. The desired output of this vision system is accurate, real-time locations for individual aliens and accurate statistical data as to the frequency of illegal border crossings. Because most detection and tracking routines assume rigid body motion, which is not characteristic of humans, new algorithms capable of reliable operation in our application are required. Furthermore, most current detection and tracking algorithms assume a uniform background against which motion is viewed - the urban environment along the US-Mexican border is anything but uniform. The system works in three stages: motion detection, object tracking and object identi-fication. We have implemented motion detection using simple frame differencing, maximum likelihood estimation, mean and median tests and are evaluating them for accuracy and computational efficiency. Due to the complex nature of the urban environment (background and foreground objects consisting of buildings, vegetation, vehicles, wind-blown debris, animals, etc.), motion detection alone is not sufficiently accurate. Object tracking and identification are handled by an expert system which takes shape, location and trajectory information as input and determines if the moving object is indeed representative of an illegal border crossing.
A-Track: A new approach for detection of moving objects in FITS images
NASA Astrophysics Data System (ADS)
Atay, T.; Kaplan, M.; Kilic, Y.; Karapinar, N.
2016-10-01
We have developed a fast, open-source, cross-platform pipeline, called A-Track, for detecting the moving objects (asteroids and comets) in sequential telescope images in FITS format. The pipeline is coded in Python 3. The moving objects are detected using a modified line detection algorithm, called MILD. We tested the pipeline on astronomical data acquired by an SI-1100 CCD with a 1-meter telescope. We found that A-Track performs very well in terms of detection efficiency, stability, and processing time. The code is hosted on GitHub under the GNU GPL v3 license.
Ambiguous data association and entangled attribute estimation
NASA Astrophysics Data System (ADS)
Trawick, David J.; Du Toit, Philip C.; Paffenroth, Randy C.; Norgard, Gregory J.
2012-05-01
This paper presents an approach to attribute estimation incorporating data association ambiguity. In modern tracking systems, time pressures often leave all but the most likely data association alternatives unexplored, possibly producing track inaccuracies. Numerica's Bayesian Network Tracking Database, a key part of its Tracker Adjunct Processor, captures and manages the data association ambiguity for further analysis and possible ambiguity reduction/resolution using subsequent data. Attributes are non-kinematic discrete sample space sensor data. They may be as distinctive as aircraft ID, or as broad as friend or foe. Attribute data may provide improvements to data association by a process known as Attribute Aided Tracking (AAT). Indeed, certain uniquely identifying attributes (e.g. aircraft ID), when continually reported, can be used to define data association (tracks are the collections of observations with the same ID). However, attribute data arriving infrequently, combined with erroneous choices from ambiguous data associations, can produce incorrect attribute and kinematic state estimation. Ambiguous data associations define the tracks that are entangled with each other. Attribute data observed on an entangled track then modify the attribute estimates on all tracks entangled with it. For example, if a red track and a blue track pass through a region of data association ambiguity, these tracks become entangled. Later red observations on one entangled track make the other track more blue, and reduce the data association ambiguity. Methods for this analysis have been derived and implemented for efficient forward filtering and forensic analysis.
NASA Technical Reports Server (NTRS)
Ackerman, A. S.; Stevens, D. E.; Toon, O. B.; Coakley, J. A., Jr.; Gore, Warren J. (Technical Monitor)
2002-01-01
A number of observations and simulations have shown that increased droplet concentrations in ship tracks increase their total cross-sectional area, thereby enhancing cloud albedo and providing a negative (cooling) radiative forcing at the surface and the top of the atmosphere. In some cases cloud water has been found to be enhanced in ship tracks, which has been attributed to suppression of drizzle and implies an enhanced susceptibility of cloud albedo to droplet concentrations. However, observations from aircraft and satellite indicate that on average cloud water is instead reduced in daytime ship tracks. Such a reduction in liquid water may be attributable to cloud-burning caused by solar heating by soot within the ship exhaust, or by increased precipitation resulting from giant nuclei in the ship exhaust. We will summarize the observational evidence and present results from large-eddy simulations that evaluate these mechanisms. Along the way we will present our insights into the interpretation of satellite retrievals of cloud microphysical properties.
On the Nature of Cross-Linguistic Transfer: A Case Study of Andean Spanish
ERIC Educational Resources Information Center
Muntendam, Antje G.
2013-01-01
This paper presents the results of a study on cross-linguistic transfer in Andean Spanish word order. In Andean Spanish the object appears in preverbal position more frequently than in non-Andean Spanish, which has been attributed to an influence from Quechua (a Subject-Object-Verb language). The high frequency of preverbal objects could be…
ERIC Educational Resources Information Center
Arnold, Jennifer E.; Kam, Carla L. Hudson; Tanenhaus, Michael K.
2007-01-01
Eye-tracking and gating experiments examined reference comprehension with fluent (Click on the red. . .) and disfluent (Click on [pause] thee uh red . . .) instructions while listeners viewed displays with 2 familiar (e.g., ice cream cones) and 2 unfamiliar objects (e.g., squiggly shapes). Disfluent instructions made unfamiliar objects more…
Chen, Wan Juan; Zeng, Xingrong; Lai, Xuejun; Li, Hongqiang; Fang, Wei Zhen; Hou, Fei
2016-08-17
How to effectively improve the tracking and erosion resistance of silicone rubber (SR) was an urgent topic in the field of high-voltage insulation. In this work, the tracking and erosion resistance of SR was significantly improved by incorporating platinum (Pt) catalyst and nitrogen-containing silane (NS). The suppression effect and mechanism of Pt/NS on tracking and erosion were studied by inclined plane (IP) test, thermogravimetry (TG), thermogravimetry-Fourier transform infrared spectrometry, laser Raman spectroscopy, and scanning electron microscopy. It revealed that when 1.4 phr of NS and 6.7 ppm of Pt were added, the tracking resistance of SR was improved from 2.5 to 4.5 kV level in the IP test, and the eroded mass was significantly reduced. This might be attributed to the synergistic effect of Pt/NS on silicone chains. At a high temperature produced by arc discharge, Pt/NS would catalyze radical cross-linking, meanwhile suppressing oxidation and depolymerization of silicone chains. Hence, a tightly cross-linked network was formed and protected inner materials from arc ablation. Moreover, carbon deposit during pyrolysis was suppressed by Pt/NS, which served as the secondary mechanism of tracking suppression.
Tracking near-surface atmospheric conditions using an infrasound network.
Marcillo, O; Johnson, J B
2010-07-01
Continuous volcanic infrasound signal was recorded on a three-microphone network at Kilauea in July 2008 and inverted for near-surface horizontal winds. Inter-station phase delays, determined by signal cross-correlation, vary by up to 4% and are attributable to variable atmospheric conditions. The results suggest two predominant weather regimes during the study period: (1) 6-9 m/s easterly trade winds and (2) lower-intensity 2-5 m/s mountain breezes from Mauna Loa. The results demonstrate the potential of using infrasound for tracking local averaged meteorological conditions, which has implications for modeling plume dispersal and quantifying gas flux.
Ichnological evidence of Megalosaurid Dinosaurs Crossing Middle Jurassic Tidal Flats
NASA Astrophysics Data System (ADS)
Razzolini, Novella L.; Oms, Oriol; Castanera, Diego; Vila, Bernat; Santos, Vanda Faria Dos; Galobart, Àngel
2016-08-01
A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal)preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late Jurassic-Early Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes.
Ichnological evidence of Megalosaurid Dinosaurs Crossing Middle Jurassic Tidal Flats.
Razzolini, Novella L; Oms, Oriol; Castanera, Diego; Vila, Bernat; Santos, Vanda Faria Dos; Galobart, Àngel
2016-08-19
A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal)preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late Jurassic-Early Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes.
Tetrapod tracks in Permo-Triassic eolian beds of southern Brazil (Paraná Basin).
Francischini, Heitor; Dentzien-Dias, Paula; Lucas, Spencer G; Schultz, Cesar L
2018-01-01
Tetrapod tracks in eolianites are widespread in the fossil record since the late Paleozoic. Among these ichnofaunas, the ichnogenus Chelichnus is the most representative of the Permian tetrapod ichnological record of eolian deposits of Europe, North America and South America, where the Chelichnus Ichnofacies often occurs. In this contribution, we describe five sets of tracks (one of which is preserved in cross-section), representing the first occurrence of Dicynodontipus and Chelichnus in the "Pirambóia Formation" of southern Brazil. This unit represents a humid desert in southwestern Pangea and its lower and upper contacts lead us to consider its age as Lopingian-Induan. The five sets of tracks studied were compared with several ichnotaxa and body fossils with appendicular elements preserved, allowing us to attribute these tracks to dicynodonts and other indeterminate therapsids. Even though the "Pirambóia Formation" track record is sparse and sub-optimally preserved, it is an important key to better understand the occupation of arid environments by tetrapods across the Permo-Triassic boundary.
Duration, distance, and speed judgments of two moving objects by 4- to 11-year olds.
Matsuda, F
1996-11-01
Four- to 11-year-old children (N = 133) made duration, distance, and speed judgments on a Piagetian task where two cars ran on two parallel tracks. Special effort was made to make duration judgment tasks and distance judgment tasks comparable. Among younger children, difficulties of duration judgments and distance judgments were approximately the same. Additionally, temporal attributes had nearly the same effects on duration judgments as spatial attributes had on distance judgments, and spatial attributes had nearly the same effects on duration judgments as temporal attributes had on distance judgments. Among older children, distance judgments were easier than duration judgments, and the above-mentioned symmetry in effects of temporal and spatial attributes decreased somewhat. Temporal and spatial attributes affected speed judgments equally, across age groups.
Doublet Pulse Coherent Laser Radar for Tracking of Resident Space Objects
NASA Technical Reports Server (NTRS)
Prasad, Narasimha S.; Rudd, Van; Shald, Scott; Sandford, Stephen; Dimarcantonio, Albert
2014-01-01
In this paper, the development of a long range ladar system known as ExoSPEAR at NASA Langley Research Center for tracking rapidly moving resident space objects is discussed. Based on 100 W, nanosecond class, near-IR laser, this ladar system with coherent detection technique is currently being investigated for short dwell time measurements of resident space objects (RSOs) in LEO and beyond for space surveillance applications. This unique ladar architecture is configured using a continuously agile doublet-pulse waveform scheme coupled to a closed-loop tracking and control loop approach to simultaneously achieve mm class range precision and mm/s velocity precision and hence obtain unprecedented track accuracies. Salient features of the design architecture followed by performance modeling and engagement simulations illustrating the dependence of range and velocity precision in LEO orbits on ladar parameters are presented. Estimated limits on detectable optical cross sections of RSOs in LEO orbits are discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Duberstein, Corey A.; Matzner, Shari; Cullinan, Valerie I.
Surveying wildlife at risk from offshore wind energy development is difficult and expensive. Infrared video can be used to record birds and bats that pass through the camera view, but it is also time consuming and expensive to review video and determine what was recorded. We proposed to conduct algorithm and software development to identify and to differentiate thermally detected targets of interest that would allow automated processing of thermal image data to enumerate birds, bats, and insects. During FY2012 we developed computer code within MATLAB to identify objects recorded in video and extract attribute information that describes the objectsmore » recorded. We tested the efficiency of track identification using observer-based counts of tracks within segments of sample video. We examined object attributes, modeled the effects of random variability on attributes, and produced data smoothing techniques to limit random variation within attribute data. We also began drafting and testing methodology to identify objects recorded on video. We also recorded approximately 10 hours of infrared video of various marine birds, passerine birds, and bats near the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) at Sequim, Washington. A total of 6 hours of bird video was captured overlooking Sequim Bay over a series of weeks. An additional 2 hours of video of birds was also captured during two weeks overlooking Dungeness Bay within the Strait of Juan de Fuca. Bats and passerine birds (swallows) were also recorded at dusk on the MSL campus during nine evenings. An observer noted the identity of objects viewed through the camera concurrently with recording. These video files will provide the information necessary to produce and test software developed during FY2013. The annotation will also form the basis for creation of a method to reliably identify recorded objects.« less
Near-Earth Object Orbit Linking with the Large Synoptic Survey Telescope
NASA Astrophysics Data System (ADS)
Vereš, Peter; Chesley, Steven R.
2017-07-01
We have conducted a detailed simulation of the ability of the Large Synoptic Survey Telescope (LSST) to link near-Earth and main belt asteroid detections into orbits. The key elements of the study were a high-fidelity detection model and the presence of false detections in the form of both statistical noise and difference image artifacts. We employed the Moving Object Processing System (MOPS) to generate tracklets, tracks, and orbits with a realistic detection density for one month of the LSST survey. The main goals of the study were to understand whether (a) the linking of near-Earth objects (NEOs) into orbits can succeed in a realistic survey, (b) the number of false tracks and orbits will be manageable, and (c) the accuracy of linked orbits would be sufficient for automated processing of discoveries and attributions. We found that the overall density of asteroids was more than 5000 per LSST field near opposition on the ecliptic, plus up to 3000 false detections per field in good seeing. We achieved 93.6% NEO linking efficiency for H< 22 on tracks composed of tracklets from at least three distinct nights within a 12 day interval. The derived NEO catalog was comprised of 96% correct linkages. Less than 0.1% of orbits included false detections, and the remainder of false linkages stemmed from main belt confusion, which was an artifact of the short time span of the simulation. The MOPS linking efficiency can be improved by refined attribution of detections to known objects and by improved tuning of the internal kd-tree linking algorithms.
Cross-Situational Learning of Minimal Word Pairs
ERIC Educational Resources Information Center
Escudero, Paola; Mulak, Karen E.; Vlach, Haley A.
2016-01-01
"Cross-situational statistical learning" of words involves tracking co-occurrences of auditory words and objects across time to infer word-referent mappings. Previous research has demonstrated that learners can infer referents across sets of very phonologically distinct words (e.g., WUG, DAX), but it remains unknown whether learners can…
NASA Astrophysics Data System (ADS)
Kerns, Brandon W.; Chen, Shuyi S.
2016-08-01
A large-scale precipitation tracking (LPT) method is developed to track convection and precipitation associated with the Madden-Julian oscillation (MJO) using the Tropical Rainfall Measurement Mission 3B42 rainfall data from October to March 1998-2015. LPT uses spatially smoothed 3 day rainfall accumulation to identify and track precipitation features in time with a minimum size of 300,000 km2 and time continuity at least 10 days. While not all LPT systems (LPTs) are attributable to the MJO, among the 199 LPTs, there were 42 with a mean eastward propagation of at least 2 m s-1, which are considered to be MJO convective initiation events. These LPTs capture the diversity of the MJO convection, which is not well depicted by the Real-time Multivariate MJO (RMM) index or the outgoing longwave radiation MJO index. During the 17 years, there were 17 instances out of 45 with a MJO signature in the RMM without eastward propagating LPTs. Among the 42 eastward propagating LPTs, 24 propagated across the Maritime Continent (MC), which confirms the MC barrier effect. Among the cases that crossed the MC from the Indian Ocean to the western Pacific (MC crossing), 18 (75%) had a significant MJO signature in the RMM index. In contrast, only six (33%) of the non-MC-crossing cases occurred with a RMM MJO signal. There is a significant seasonal and interannual variability with MC-crossing LPTs occurring in December more commonly than other months. More MC-crossing events were observed during La Niña than El Niño, which is consistent with the observations of stronger and more frequent MJO events identified by RMM during La Niña years.
Object tracking via background subtraction for monitoring illegal activity in crossroad
NASA Astrophysics Data System (ADS)
Ghimire, Deepak; Jeong, Sunghwan; Park, Sang Hyun; Lee, Joonwhoan
2016-07-01
In the field of intelligent transportation system a great number of vision-based techniques have been proposed to prevent pedestrians from being hit by vehicles. This paper presents a system that can perform pedestrian and vehicle detection and monitoring of illegal activity in zebra crossings. In zebra crossing, according to the traffic light status, to fully avoid a collision, a driver or pedestrian should be warned earlier if they possess any illegal moves. In this research, at first, we detect the traffic light status of pedestrian and monitor the crossroad for vehicle pedestrian moves. The background subtraction based object detection and tracking is performed to detect pedestrian and vehicles in crossroads. Shadow removal, blob segmentation, trajectory analysis etc. are used to improve the object detection and classification performance. We demonstrate the experiment in several video sequences which are recorded in different time and environment such as day time and night time, sunny and raining environment. Our experimental results show that such simple and efficient technique can be used successfully as a traffic surveillance system to prevent accidents in zebra crossings.
NASA Technical Reports Server (NTRS)
Siapkaras, A.
1977-01-01
A computational method to deal with the multidimensional nature of tracking and/or monitoring tasks is developed. Operator centered variables, including the operator's perception of the task, are considered. Matrix ratings are defined based on multidimensional scaling techniques and multivariate analysis. The method consists of two distinct steps: (1) to determine the mathematical space of subjective judgements of a certain individual (or group of evaluators) for a given set of tasks and experimental conditionings; and (2) to relate this space with respect to both the task variables and the objective performance criteria used. Results for a variety of second-order trackings with smoothed noise-driven inputs indicate that: (1) many of the internally perceived task variables form a nonorthogonal set; and (2) the structure of the subjective space varies among groups of individuals according to the degree of familiarity they have with such tasks.
ERIC Educational Resources Information Center
Chen, Chi-hsin; Gershkoff-Stowe, Lisa; Wu, Chih-Yi; Cheung, Hintat; Yu, Chen
2017-01-01
Two experiments were conducted to examine adult learners' ability to extract multiple statistics in simultaneously presented visual and auditory input. Experiment 1 used a cross-situational learning paradigm to test whether English speakers were able to use co-occurrences to learn word-to-object mappings and concurrently form object categories…
Predicting Aggressive Tendencies by Visual Attention Bias Associated with Hostile Emotions
Lin, Ping-I; Hsieh, Cheng-Da; Juan, Chi-Hung; Hossain, Md Monir; Erickson, Craig A.; Lee, Yang-Han; Su, Mu-Chun
2016-01-01
The goal of the current study is to clarify the relationship between social information processing (e.g., visual attention to cues of hostility, hostility attribution bias, and facial expression emotion labeling) and aggressive tendencies. Thirty adults were recruited in the eye-tracking study that measured various components in social information processing. Baseline aggressive tendencies were measured using the Buss-Perry Aggression Questionnaire (AQ). Visual attention towards hostile objects was measured as the proportion of eye gaze fixation duration on cues of hostility. Hostility attribution bias was measured with the rating results for emotions of characters in the images. The results show that the eye gaze duration on hostile characters was significantly inversely correlated with the AQ score and less eye contact with an angry face. The eye gaze duration on hostile object was not significantly associated with hostility attribution bias, although hostility attribution bias was significantly positively associated with the AQ score. Our findings suggest that eye gaze fixation time towards non-hostile cues may predict aggressive tendencies. PMID:26901770
Predicting Aggressive Tendencies by Visual Attention Bias Associated with Hostile Emotions.
Lin, Ping-I; Hsieh, Cheng-Da; Juan, Chi-Hung; Hossain, Md Monir; Erickson, Craig A; Lee, Yang-Han; Su, Mu-Chun
2016-01-01
The goal of the current study is to clarify the relationship between social information processing (e.g., visual attention to cues of hostility, hostility attribution bias, and facial expression emotion labeling) and aggressive tendencies. Thirty adults were recruited in the eye-tracking study that measured various components in social information processing. Baseline aggressive tendencies were measured using the Buss-Perry Aggression Questionnaire (AQ). Visual attention towards hostile objects was measured as the proportion of eye gaze fixation duration on cues of hostility. Hostility attribution bias was measured with the rating results for emotions of characters in the images. The results show that the eye gaze duration on hostile characters was significantly inversely correlated with the AQ score and less eye contact with an angry face. The eye gaze duration on hostile object was not significantly associated with hostility attribution bias, although hostility attribution bias was significantly positively associated with the AQ score. Our findings suggest that eye gaze fixation time towards non-hostile cues may predict aggressive tendencies.
NASA Astrophysics Data System (ADS)
Kohn, V. G.; Argunova, T. S.; Je, J. H.
2010-11-01
We show that x-ray phase contrast images of some objects with a small cross-section diameter d satisfy a condition for a far-field approximation d Lt r1 where r1 = (λz)1/2, λ is the x-ray wavelength, z is the distance from the object to the detector. In this case the size of the image does not match the size of the object contrary to the edge detection technique. Moreover, the structure of the central fringes of the image is universal, i.e. it is independent of the object cross-section structure. Therefore, these images have no detailed information on the object.
Integrated Eye Tracking and Neural Monitoring for Enhanced Assessment of Mild TBI
2016-04-01
and we anticipate the initiation of the neuroimaging portion of the study early in Year 3. The fMRI task has been completed and is in beta testing...neurocognitive test battery, and self-report measures of cognitive efficacy. We will also include functional magnetic resonance imagining ( fMRI ) and... fMRI and DTI will provide an objective basis for cross-validating the EEG and eye tracking system. Both the EEG and eye tracking data will be
Multiple-hypothesis multiple-model line tracking
NASA Astrophysics Data System (ADS)
Pace, Donald W.; Owen, Mark W.; Cox, Henry
2000-07-01
Passive sonar signal processing generally includes tracking of narrowband and/or broadband signature components observed on a Lofargram or on a Bearing-Time-Record (BTR) display. Fielded line tracking approaches to date have been recursive and single-hypthesis-oriented Kalman- or alpha-beta filters, with no mechanism for considering tracking alternatives beyond the most recent scan of measurements. While adaptivity is often built into the filter to handle changing track dynamics, these approaches are still extensions of single target tracking solutions to multiple target tracking environment. This paper describes an application of multiple-hypothesis, multiple target tracking technology to the sonar line tracking problem. A Multiple Hypothesis Line Tracker (MHLT) is developed which retains the recursive minimum-mean-square-error tracking behavior of a Kalman Filter in a maximum-a-posteriori delayed-decision multiple hypothesis context. Multiple line track filter states are developed and maintained using the interacting multiple model (IMM) state representation. Further, the data association and assignment problem is enhanced by considering line attribute information (line bandwidth and SNR) in addition to beam/bearing and frequency fit. MHLT results on real sonar data are presented to demonstrate the benefits of the multiple hypothesis approach. The utility of the system in cluttered environments and particularly in crossing line situations is shown.
Challenges in Requirements Engineering: A Research Agenda for Conceptual Modeling
NASA Astrophysics Data System (ADS)
March, Salvatore T.; Allen, Gove N.
Domains for which information systems are developed deal primarily with social constructions—conceptual objects and attributes created by human intentions and for human purposes. Information systems play an active role in these domains. They document the creation of new conceptual objects, record and ascribe values to their attributes, initiate actions within the domain, track activities performed, and infer conclusions based on the application of rules that govern how the domain is affected when socially-defined and identified causal events occur. Emerging applications of information technologies evaluate such business rules, learn from experience, and adapt to changes in the domain. Conceptual modeling grammars aimed at representing their system requirements must include conceptual objects, socially-defined events, and the rules pertaining to them. We identify challenges to conceptual modeling research and pose an ontology of the artificial as a step toward meeting them.
Tetrapod tracks in Permo–Triassic eolian beds of southern Brazil (Paraná Basin)
Dentzien-Dias, Paula; Lucas, Spencer G.; Schultz, Cesar L.
2018-01-01
Tetrapod tracks in eolianites are widespread in the fossil record since the late Paleozoic. Among these ichnofaunas, the ichnogenus Chelichnus is the most representative of the Permian tetrapod ichnological record of eolian deposits of Europe, North America and South America, where the Chelichnus Ichnofacies often occurs. In this contribution, we describe five sets of tracks (one of which is preserved in cross-section), representing the first occurrence of Dicynodontipus and Chelichnus in the “Pirambóia Formation” of southern Brazil. This unit represents a humid desert in southwestern Pangea and its lower and upper contacts lead us to consider its age as Lopingian–Induan. The five sets of tracks studied were compared with several ichnotaxa and body fossils with appendicular elements preserved, allowing us to attribute these tracks to dicynodonts and other indeterminate therapsids. Even though the “Pirambóia Formation” track record is sparse and sub-optimally preserved, it is an important key to better understand the occupation of arid environments by tetrapods across the Permo–Triassic boundary. PMID:29796341
NASA Technical Reports Server (NTRS)
Rickman, Doug; Shire, J.; Qualters, J.; Mitchell, K.; Pollard, S.; Rao, R.; Kajumba, N.; Quattrochi, D.; Estes, M., Jr.; Meyer, P.;
2009-01-01
Objectives. To provide an overview of four environmental public health surveillance projects developed by CDC and its partners for the Health and Environment Linked for Information Exchange, Atlanta (HELIX-Atlanta) and to illustrate common issues and challenges encountered in developing an environmental public health tracking system. Methods. HELIX-Atlanta, initiated in October 2003 to develop data linkage and analysis methods that can be used by the National Environmental Public Health Tracking Network (Tracking Network), conducted four projects. We highlight the projects' work, assess attainment of the HELIX-Atlanta goals and discuss three surveillance attributes. Results. Among the major challenges was the complexity of analytic issues which required multidiscipline teams with technical expertise. This expertise and the data resided across multiple organizations. Conclusions:Establishing formal procedures for sharing data, defining data analysis standards and automating analyses, and committing staff with appropriate expertise is needed to support wide implementation of environmental public health tracking.
The Establishment of a Formal Midwest Renewable Energy Tracking System (M-RETS) Organization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Maria Redmond; Chela Bordas O'Connor
2010-06-30
The objectives identified in requesting and utilizing this funding has been met. The goal was to establish a formal, multi-jurisdictional organization to: (1) ensure the policy objectives of the participating jurisdictions are addressed through increased tradability of the Renewable Energy Credits (RECs) from M-RETS and to eliminate the possibility that a single jurisdiction will be the sole arbiter of the operation of the system; (2) facilitate the establishment of REC standards including the attributes related to, the creation, trading, and interaction with other trading and tracking systems; and (3) have a centralized and established organization that will be responsible formore » the contracting and governance responsibilities of a multi-jurisdictional tracking system. The M-RETS Inc. Board ensures that the system remains policy neutral; that the attributes of generation are tracked in a way that allows the system users to easily identify and trade relevant RECs; that the system can add jurisdictions as needed or desired; and that the tracking system operate in such a way to allow for the greatest access possible for those participating in other tracking or trading systems by allowing those systems to negotiate with a single M-RETS entity for the import and export of RECs. M-RETS as an organizational body participates and often leads the discussions related to the standardization of RECs and increasing the tradability of M-RETS RECs. M-RETS is a founding member of the Environmental Trading Network of North America (ETNNA) and continues to take a leadership role in the development of processes to facilitate trading among tracking systems and to standardize REC definitions. The Board of Directors of M-RETS, Inc., the non-profit corporation, continues to hold telephone/internet Board meetings. Legal counsel continues working with the board and APX management on a new agreement with APX. The board expects to have an agreement and corresponding fee structure in place by January 2011. The Board has recently approved exports to three other tracking systems and is in discussions about imports to the system. Below are the tasks outlined in the request and attached you will find the relevant documentation.« less
A Bootstrapping Model of Frequency and Context Effects in Word Learning
ERIC Educational Resources Information Center
Kachergis, George; Yu, Chen; Shiffrin, Richard M.
2017-01-01
Prior research has shown that people can learn many nouns (i.e., word--object mappings) from a short series of ambiguous situations containing multiple words and objects. For successful cross-situational learning, people must approximately track which words and referents co-occur most frequently. This study investigates the effects of allowing…
Tracking Objects with Networked Scattered Directional Sensors
NASA Astrophysics Data System (ADS)
Plarre, Kurt; Kumar, P. R.
2007-12-01
We study the problem of object tracking using highly directional sensors—sensors whose field of vision is a line or a line segment. A network of such sensors monitors a certain region of the plane. Sporadically, objects moving in straight lines and at a constant speed cross the region. A sensor detects an object when it crosses its line of sight, and records the time of the detection. No distance or angle measurements are available. The task of the sensors is to estimate the directions and speeds of the objects, and the sensor lines, which are unknown a priori. This estimation problem involves the minimization of a highly nonconvex cost function. To overcome this difficulty, we introduce an algorithm, which we call "adaptive basis algorithm." This algorithm is divided into three phases: in the first phase, the algorithm is initialized using data from six sensors and four objects; in the second phase, the estimates are updated as data from more sensors and objects are incorporated. The third phase is an optional coordinated transformation. The estimation is done in an "ad-hoc" coordinate system, which we call "adaptive coordinate system." When more information is available, for example, the location of six sensors, the estimates can be transformed to the "real-world" coordinate system. This constitutes the third phase.
Sampling Analysis of Aerosol Retrievals by Single-track Spaceborne Instrument for Climate Research
NASA Astrophysics Data System (ADS)
Geogdzhayev, I. V.; Cairns, B.; Alexandrov, M. D.; Mishchenko, M. I.
2012-12-01
We examine to what extent the reduced sampling of along-track instruments such as Cloud-Aerosol LIdar with Orthogonal Polarisation (CALIOP) and Aerosol Polarimetry Sensor (APS) affects the statistical accuracy of a satellite climatology of retrieved aerosol optical thickness (AOT) by sub-sampling the retrievals from a wide-swath imaging instrument (MODerate resolution Imaging Spectroradiometer (MODIS)). Owing to its global coverage, longevity, and extensive characterization versus ground based data, the MODIS level-2 aerosol product is an instructive testbed for assessing sampling effects on climatic means derived from along-track instrument data. The advantage of using daily pixel-level aerosol retrievals from MODIS is that limitations caused by the presence of clouds are implicit in the sample, so that their seasonal and regional variations are captured coherently. However, imager data can exhibit cross-track variability of monthly global mean AOTs caused by a scattering-angle dependence. We found that single along-track values can deviate from the imager mean by 15% over land and by more than 20% over ocean. This makes it difficult to separate natural variability from viewing-geometry artifacts complicating direct comparisons of an along-track sub-sample with the full imager data. To work around this problem, we introduce "flipped-track" sampling which, by design, is statistically equivalent to along-track sampling and while closely approximating the imager in terms of angular artifacts. We show that the flipped-track variability of global monthly mean AOT is much smaller than the cross-track one for the 7-year period considered. Over the ocean flipped-track standard error is 85% less than the cross-track one (absolute values 0.0012 versus 0.0079), and over land it is about one third of the cross-track value (0.0054 versus 0.0188) on average. This allows us to attribute the difference between the two errors to the viewing-geometry artifacts and obtain an upper limit on AOT errors caused by along-track sampling. Our results show that using along-track subsets of MODIS aerosol data directly to analyze the sampling adequacy of single-track instruments can lead to false conclusions owing to the apparent enhancement of natural aerosol variability by the track-to-track artifacts. The analysis based on the statistics of the flipped-track means yields better estimates because it allows for better separation of the viewing-geometry artifacts and true natural variability. Published assessments estimate that a global AOT change of 0.01 would yield a climatically important flux change of 0.25 W/m2. Since the standard error estimates that we have obtained are comfortably below 0.01, we conclude that along-track instruments flown on a sun-synchronous orbiting platform have sufficient spatial sampling for estimating aerosol effects on climate. Since AOT is believed to be the most variable characteristic of tropospheric aerosols, our results imply that pixel-wide along-track coverage also provides adequate statistical representation of the global distribution of aerosol microphysical parameters.
Semi-automated location identification of catheters in digital chest radiographs
NASA Astrophysics Data System (ADS)
Keller, Brad M.; Reeves, Anthony P.; Cham, Matthew D.; Henschke, Claudia I.; Yankelevitz, David F.
2007-03-01
Localization of catheter tips is the most common task in intensive care unit imaging. In this work, catheters appearing in digital chest radiographs acquired by portable chest x-rays were tracked using a semi-automatic method. Due to the fact that catheters are synthetic objects, its profile does not vary drastically over its length. Therefore, we use forward looking registration with normalized cross-correlation in order to take advantage of a priori information of the catheter profile. The registration is accomplished with a two-dimensional template representative of the catheter to be tracked generated using two seed points given by the user. To validate catheter tracking with this method, we look at two metrics: accuracy and precision. The algorithms results are compared to a ground truth established by catheter midlines marked by expert radiologists. Using 12 objects of interest comprised of naso-gastric, endo-tracheal tubes, and chest tubes, and PICC and central venous catheters, we find that our algorithm can fully track 75% of the objects of interest, with a average tracking accuracy and precision of 85.0%, 93.6% respectively using the above metrics. Such a technique would be useful for physicians wishing to verify the positioning of catheter tips using chest radiographs.
Castanera, Diego; Vila, Bernat; Razzolini, Novella L; Falkingham, Peter L; Canudo, José I; Manning, Phillip L; Galobart, Angel
2013-01-01
The Las Cerradicas site (Tithonian-Berriasian), Teruel, Spain, preserves at least seventeen dinosaur trackways, some of them formerly attributed to quadrupedal ornithopods, sauropods and theropods. The exposure of new track evidence allows a more detailed interpretation of the controversial tridactyl trackways as well as the modes of locomotion and taxonomic affinities of the trackmakers. Detailed stratigraphic analysis reveals four different levels where footprints have been preserved in different modes. Within the tridactyl trackways, manus tracks are mainly present in a specific horizon relative to surface tracks. The presence of manus tracks is interpreted as evidence of an ornithopod trackmaker. Cross-sections produced from photogrammetric digital models show different depths of the pes and manus, suggesting covariance in loading between the forelimbs and the hindlimbs. Several features (digital pads, length/width ratio, claw marks) of some ornithopod pes tracks from Las Cerradicas are reminiscent of theropod pedal morphology. This morphological convergence, combined with the shallow nature of the manus tracks, which reduces preservation potential, opens a new window into the interpretation of these tridactyl tracks. Thus, trackmaker assignations during the Jurassic-Cretaceous interval of purported theropod trackways may potentially represent ornithopods. Moreover, the Las Cerradicas trackways are further evidence for quadrupedalism among some basal small- to medium-sized ornithopods from this time interval.
Study of moving object detecting and tracking algorithm for video surveillance system
NASA Astrophysics Data System (ADS)
Wang, Tao; Zhang, Rongfu
2010-10-01
This paper describes a specific process of moving target detecting and tracking in the video surveillance.Obtain high-quality background is the key to achieving differential target detecting in the video surveillance.The paper is based on a block segmentation method to build clear background,and using the method of background difference to detecing moving target,after a series of treatment we can be extracted the more comprehensive object from original image,then using the smallest bounding rectangle to locate the object.In the video surveillance system, the delay of camera and other reasons lead to tracking lag,the model of Kalman filter based on template matching was proposed,using deduced and estimated capacity of Kalman,the center of smallest bounding rectangle for predictive value,predicted the position in the next moment may appare,followed by template matching in the region as the center of this position,by calculate the cross-correlation similarity of current image and reference image,can determine the best matching center.As narrowed the scope of searching,thereby reduced the searching time,so there be achieve fast-tracking.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-23
... a track-and-trace system and for obtaining input from supply chain partners on potential attributes...-trace system and (2) input from supply chain partners on potential attributes and standards for the...
NASA Astrophysics Data System (ADS)
Petrochenko, Andrey; Konyakhin, Igor
2017-06-01
In connection with the development of robotics have become increasingly popular variety of three-dimensional reconstruction of the system mapping and image-set received from the optical sensors. The main objective of technical and robot vision is the detection, tracking and classification of objects of the space in which these systems and robots operate [15,16,18]. Two-dimensional images sometimes don't contain sufficient information to address those or other problems: the construction of the map of the surrounding area for a route; object identification, tracking their relative position and movement; selection of objects and their attributes to complement the knowledge base. Three-dimensional reconstruction of the surrounding space allows you to obtain information on the relative positions of objects, their shape, surface texture. Systems, providing training on the basis of three-dimensional reconstruction of the results of the comparison can produce two-dimensional images of three-dimensional model that allows for the recognition of volume objects on flat images. The problem of the relative orientation of industrial robots with the ability to build threedimensional scenes of controlled surfaces is becoming actual nowadays.
ERIC Educational Resources Information Center
Ritchie, Lorrene D.; Raman, Aarthi; Sharma, Sushma; Fitch, Mark D.; Fleming, Sharon E.
2011-01-01
Objective: To identify family and child nutrition and dietary attributes related to children's dietary intakes. Design: African American children (ages 8-11 years, n = 156), body mass index greater than 85th percentile, from urban, low-income neighborhoods. Baseline, cross-sectional data collected as part of an ongoing diabetes prevention…
Method of center localization for objects containing concentric arcs
NASA Astrophysics Data System (ADS)
Kuznetsova, Elena G.; Shvets, Evgeny A.; Nikolaev, Dmitry P.
2015-02-01
This paper proposes a method for automatic center location of objects containing concentric arcs. The method utilizes structure tensor analysis and voting scheme optimized with Fast Hough Transform. Two applications of the proposed method are considered: (i) wheel tracking in video-based system for automatic vehicle classification and (ii) tree growth rings analysis on a tree cross cut image.
Inferring difficulty: Flexibility in the real-time processing of disfluency
Heller, Daphna; Arnold, Jennifer E.; Klein, Natalie M.; Tanenhaus, Michael K.
2015-01-01
Upon hearing a disfluent referring expression, listeners expect the speaker to refer to an object that is previously-unmentioned, an object that does not have a straightforward label, or an object that requires a longer description. Two visual-world eye-tracking experiments examined whether listeners directly associate disfluency with these properties of objects, or whether disfluency attribution is more flexible and involves situation-specific inferences. Since in natural situations reference to objects that do not have a straightforward label or that require a longer description is correlated with both production difficulty and with disfluency, we used a mini artificial lexicon to dissociate difficulty from these properties, building on the fact that recently-learned names take longer to produce than existing words in one’s mental lexicon. The results demonstrate that disfluency attribution involves situation-specific inferences; we propose that in new situations listeners spontaneously infer what may cause production difficulty. However, the results show that these situation-specific inferences are limited in scope: listeners assessed difficulty relative to their own experience with the artificial names, and did not adapt to the assumed knowledge of the speaker. PMID:26677642
Effects of target shape and reflection on laser radar cross sections.
Steinvall, O
2000-08-20
Laser radar cross sections have been evaluated for a number of ideal targets such as cones, spheres, paraboloids, and cylinders by use of different reflection characteristics. The time-independent cross section is the ratio of the cross section of one of these forms to that of a plate with the same maximum radius. The time-dependent laser radar cross section involves the impulse response from the object shape multiplied by the beam's transverse profile and the surface bidirectional reflection distribution function. It can be clearly seen that knowledge of the combined effect of object shape and reflection characteristics is important for determining the shape and the magnitude of the laser radar return. The results of this study are of interest for many laser radar applications such as ranging, three-dimensional imaging-modeling, tracking, antisensor lasers, and target recognition.
Airborne Grid Sea-Ice Surveys for Comparison with Cryosat-2
NASA Astrophysics Data System (ADS)
Brozena, J. M.; Gardner, J. M.; Liang, R.; Hagen, R. A.; Ball, D.; Newman, T.
2015-12-01
The Naval Research Laboratory is studying of the changing Arctic with a focus on ice thickness and distribution variability. The goal is optimization of computer models used to predict sea ice changes. An important part of our study is to calibrate/validate Cryosat-2 ice thickness data prior to its incorporation into new ice forecast models. The footprint of the altimeter over sea-ice is a significant issue in any attempt to ground-truth the data. Along-track footprints are reduced to ~ 300 m by SAR processing of the returns. However, the cross-track footprint is determined by the topography of the surface. Further, the actual return is the sum of the returns from individual reflectors within the footprint making it difficult to interpret the return, and optimize the waveform tracker. We therefore collected a series of grids of scanning LiDAR and radar on sub-satellite tracks over sea-ice that would extend far enough cross-track to capture the illuminated area. The difficulty in the collection of such grids, which are comprised of adjacent overlapping tracks is ice motion of as much as 300 m over the duration of a single flight track (~ 20 km) of data collection. With a typical LiDAR swath width of < 500m adjustment of the survey tracks in near real-time for the ice motion is necessary for a coherent data set. This was accomplished by a an NRL devised photogrammetric method of ice velocity determination. Post-processing refinements resulted in typical track-to-track miss-ties of ~ 1-2 m, much of which could be attributed to ice deformation over the period of the survey. This allows us to reconstruct the ice configuration to the time of the satellite overflight, resulting in a good picture of the surface actually illuminated by the radar. The detailed 2-d LiDAR image is the snow surface, not the underlying ice presumably illuminated by the radar. Our hope is that the 1-D radar profiles collected along the LiDAR swath centerlines will be sufficient to correct the grid for snow thickness. A total of 15 grids 5-20 km wide (cross-track) by 10-30 km long (along-track) centered on ice illuminated by CryoSat-2 were collected north of Barrow, AK. This occured over three field seasons which took place from 2013-15. Data from the grids are shown here and are being used to examine the relationship of the tracked satellite waveform data to the actual surface.
Integrated Eye Tracking and Neural Monitoring for Enhanced Assessment of Mild TBI
2016-04-01
but these delays are nearing resolution and we anticipate the initiation of the neuroimaging portion of the study early in Year 3. The fMRI task...resonance imagining ( fMRI ) and diffusion tensor imaging (DTI) to characterize the extent of functional cortical recruitment and white matter injury...respectively. The inclusion of fMRI and DTI will provide an objective basis for cross-validating the EEG and eye tracking system. Both the EEG and eye
Lie, Arve; Skogstad, Marit; Johnsen, Torstein Seip; Engdahl, Bo; Tambs, Kristian
2014-01-01
Objective Railway workers performing maintenance work of trains and tracks could be at risk of developing noise-induced hearing loss, since they are exposed to noise levels of 75–90 dB(A) with peak exposures of 130–140 dB(C). The objective was to make a risk assessment by comparing the hearing thresholds among train and track maintenance workers with a reference group not exposed to noise and reference values from the ISO 1999. Design Cross-sectional. Setting A major Norwegian railway company. Participants 1897 and 2730 male train and track maintenance workers, respectively, all exposed to noise, and 2872 male railway traffic controllers and office workers not exposed to noise. Outcome measures The primary outcome was the hearing threshold (pure tone audiometry, frequencies from 0.5 to 8 kHz), and the secondary outcome was the prevalence of audiometric notches (Coles notch) of the most recent audiogram. Results Train and track maintenance workers aged 45 years or older had a small mean hearing loss in the 3–6 kHz area of 3–5 dB. The hearing loss was less among workers younger than 45 years. Audiometric notches were slightly more prevalent among the noise exposed (59–64%) group compared with controls (49%) for all age groups. They may therefore be a sensitive measure in disclosing an early hearing loss at a group level. Conclusions Train and track maintenance workers aged 45 years or older, on average, have a slightly greater hearing loss and more audiometric notches compared with reference groups not exposed to noise. Younger (<45 years) workers have hearing thresholds comparable to the controls. PMID:25324318
Airborne Grid Sea-Ice Surveys for Comparison with CryoSat-2
NASA Astrophysics Data System (ADS)
Brozena, J. M.; Gardner, J. M.; Liang, R.; Hagen, R. A.; Ball, D.
2014-12-01
The U.S. Naval Research Laboratory is engaged in a study of the changing Arctic with a particular focus on ice thickness and distribution variability. The purpose is to optimize computer models used to predict sea ice changes. An important part of our study is to calibrate/validate CryoSat-2 ice thickness data prior to its incorporation into new ice forecast models. The large footprint of the CryoSat-2 altimeter over sea-ice is a significant issue in any attempt to ground-truth the data. Along-track footprints are reduced to ~ 300 m by SAR processing of the returns. However, the cross-track footprint is determined by the topography of the surface. Further, the actual return is the sum of the returns from individual reflectors within the footprint making it difficult to interpret the return, and optimize the waveform tracker. We therefore collected a series of grids of airborne scanning lidar and nadir pointing radar on sub-satellite tracks over sea-ice that would extend far enough cross-track to capture the illuminated area. One difficulty in the collection of grids comprised of adjacent overlapping tracks is that the ice moves as much as 300 m over the duration of a single track (~ 10 min). With a typical lidar swath width of 500m we needed to adjust the survey tracks in near real-time for the ice motion. This was accomplished by a photogrammetric method of ice velocity determination (RTIME) reported in another presentation. Post-processing refinements resulted in typical track-to-track miss-ties of ~ 1-2 m, much of which could be attributed to ice deformation over the period of the survey. An important factor is that we were able to reconstruct the ice configuration at the time of the satellite overflight, resulting in an accurate representation of the surface illuminated by CryoSat-2. Our intention is to develop a model of the ice surface using the lidar grid which includes both snow and ice using radar profiles to determine snow thickness. In 2013 a set of 6 usable grids 5-20 km wide (cross-track) by 10-30 km long were collected north of Barrow, AK. In 2014 a further 5 narrower grids (~5km) were collected. Data from these grids are shown here and will be used to examine the relationship of the tracked satellite waveform data to the actual surface.
Sharma, Giriraj K; Sofferman, Robert A; Armstrong, William B
2017-08-01
The American College of Surgeons Thyroid and Parathyroid Ultrasound Skills-Oriented Course (TPUSC) was designed to teach surgeons how to interpret and perform office-based head and neck ultrasound (HNUS). The objective of this study was to survey attendees of the TPUSC to evaluate the usefulness of the course, to track surgeon performed HNUS practice patterns, and to help identify potential roadblocks to incorporation of HNUS into a surgeon's practice. Cross-sectional survey. A Web-based survey was sent to 952 surgeons who completed the TPUSC between 2010 and 2014. Questions included surgeon specialty, practice type, Likert scale rating of the TPUSC, competency with different HNUS procedures, and current HNUS practice patterns. The response rate was 24%. On a scale from 1 (not useful) to 5 (extremely valuable), the mean course usefulness rating was 4.2. Educational goals were met for 194 (92%) surgeons, and 162 (77%) surgeons reported performing HNUS in their practice. Of 48 surgeons not performing HNUS, 24 (50%) attributed insufficient time in their clinic schedule, and 21 (44%) attributed high equipment costs. The TPUSC is a valuable educational experience for surgeons seeking to gain proficiency in HNUS. The majority of TPUSC graduates gain competency with at least one type of HNUS procedure following the course. NA Laryngoscope, 127:1950-1958, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
NASA Astrophysics Data System (ADS)
Ilieva, Tamara; Gekov, Svetoslav
2017-04-01
The Precise Point Positioning (PPP) method gives the users the opportunity to determine point locations using a single GNSS receiver. The accuracy of the determined by PPP point locations is better in comparison to the standard point positioning, due to the precise satellite orbit and clock corrections that are developed and maintained by the International GNSS Service (IGS). The aim of our current research is the accuracy assessment of the PPP method applied for surveys and tracking moving objects in GIS environment. The PPP data is collected by using preliminary developed by us software application that allows different sets of attribute data for the measurements and their accuracy to be used. The results from the PPP measurements are directly compared within the geospatial database to different other sets of terrestrial data - measurements obtained by total stations, real time kinematic and static GNSS.
Toward isolating the role of dopamine in the acquisition of incentive salience attribution.
Chow, Jonathan J; Nickell, Justin R; Darna, Mahesh; Beckmann, Joshua S
2016-10-01
Stimulus-reward learning has been heavily linked to the reward-prediction error learning hypothesis and dopaminergic function. However, some evidence suggests dopaminergic function may not strictly underlie reward-prediction error learning, but may be specific to incentive salience attribution. Utilizing a Pavlovian conditioned approach procedure consisting of two stimuli that were equally reward-predictive (both undergoing reward-prediction error learning) but functionally distinct in regard to incentive salience (levers that elicited sign-tracking and tones that elicited goal-tracking), we tested the differential role of D1 and D2 dopamine receptors and nucleus accumbens dopamine in the acquisition of sign- and goal-tracking behavior and their associated conditioned reinforcing value within individuals. Overall, the results revealed that both D1 and D2 inhibition disrupted performance of sign- and goal-tracking. However, D1 inhibition specifically prevented the acquisition of sign-tracking to a lever, instead promoting goal-tracking and decreasing its conditioned reinforcing value, while neither D1 nor D2 signaling was required for goal-tracking in response to a tone. Likewise, nucleus accumbens dopaminergic lesions disrupted acquisition of sign-tracking to a lever, while leaving goal-tracking in response to a tone unaffected. Collectively, these results are the first evidence of an intraindividual dissociation of dopaminergic function in incentive salience attribution from reward-prediction error learning, indicating that incentive salience, reward-prediction error, and their associated dopaminergic signaling exist within individuals and are stimulus-specific. Thus, individual differences in incentive salience attribution may be reflective of a differential balance in dopaminergic function that may bias toward the attribution of incentive salience, relative to reward-prediction error learning only. Copyright © 2016 Elsevier Ltd. All rights reserved.
Thermal bioaerosol cloud tracking with Bayesian classification
NASA Astrophysics Data System (ADS)
Smith, Christian W.; Dupuis, Julia R.; Schundler, Elizabeth C.; Marinelli, William J.
2017-05-01
The development of a wide area, bioaerosol early warning capability employing existing uncooled thermal imaging systems used for persistent perimeter surveillance is discussed. The capability exploits thermal imagers with other available data streams including meteorological data and employs a recursive Bayesian classifier to detect, track, and classify observed thermal objects with attributes consistent with a bioaerosol plume. Target detection is achieved based on similarity to a phenomenological model which predicts the scene-dependent thermal signature of bioaerosol plumes. Change detection in thermal sensor data is combined with local meteorological data to locate targets with the appropriate thermal characteristics. Target motion is tracked utilizing a Kalman filter and nearly constant velocity motion model for cloud state estimation. Track management is performed using a logic-based upkeep system, and data association is accomplished using a combinatorial optimization technique. Bioaerosol threat classification is determined using a recursive Bayesian classifier to quantify the threat probability of each tracked object. The classifier can accept additional inputs from visible imagers, acoustic sensors, and point biological sensors to improve classification confidence. This capability was successfully demonstrated for bioaerosol simulant releases during field testing at Dugway Proving Grounds. Standoff detection at a range of 700m was achieved for as little as 500g of anthrax simulant. Developmental test results will be reviewed for a range of simulant releases, and future development and transition plans for the bioaerosol early warning platform will be discussed.
ETHOWATCHER: validation of a tool for behavioral and video-tracking analysis in laboratory animals.
Crispim Junior, Carlos Fernando; Pederiva, Cesar Nonato; Bose, Ricardo Chessini; Garcia, Vitor Augusto; Lino-de-Oliveira, Cilene; Marino-Neto, José
2012-02-01
We present a software (ETHOWATCHER(®)) developed to support ethography, object tracking and extraction of kinematic variables from digital video files of laboratory animals. The tracking module allows controlled segmentation of the target from the background, extracting image attributes used to calculate the distance traveled, orientation, length, area and a path graph of the experimental animal. The ethography module allows recording of catalog-based behaviors from environment or from video files continuously or frame-by-frame. The output reports duration, frequency and latency of each behavior and the sequence of events in a time-segmented format, set by the user. Validation tests were conducted on kinematic measurements and on the detection of known behavioral effects of drugs. This software is freely available at www.ethowatcher.ufsc.br. Copyright © 2011 Elsevier Ltd. All rights reserved.
Data Citation in Neuroimaging: Proposed Best Practices for Data Identification and Attribution
Honor, Leah B.; Haselgrove, Christian; Frazier, Jean A.; Kennedy, David N.
2016-01-01
Data sharing and reuse, while widely accepted as good ideas, have been slow to catch on in any concrete and consistent way. One major hurdle within the scientific community has been the lack of widely accepted standards for citing that data, making it difficult to track usage and measure impact. Within the neuroimaging community, there is a need for a way to not only clearly identify and cite datasets, but also to derive new aggregate sets from multiple sources while clearly maintaining lines of attribution. This work presents a functional prototype of a system to integrate Digital Object Identifiers (DOI) and a standardized metadata schema into a XNAT-based repository workflow, allowing for identification of data at both the project and image level. These item and source level identifiers allow any newly defined combination of images, from any number of projects, to be tagged with a new group-level DOI that automatically inherits the individual attributes and provenance information of its constituent parts. This system enables the tracking of data reuse down to the level of individual images. The implementation of this type of data identification system would impact researchers and data creators, data hosting facilities, and data publishers, but the benefit of having widely accepted standards for data identification and attribution would go far toward making data citation practical and advantageous. PMID:27570508
Data Citation in Neuroimaging: Proposed Best Practices for Data Identification and Attribution.
Honor, Leah B; Haselgrove, Christian; Frazier, Jean A; Kennedy, David N
2016-01-01
Data sharing and reuse, while widely accepted as good ideas, have been slow to catch on in any concrete and consistent way. One major hurdle within the scientific community has been the lack of widely accepted standards for citing that data, making it difficult to track usage and measure impact. Within the neuroimaging community, there is a need for a way to not only clearly identify and cite datasets, but also to derive new aggregate sets from multiple sources while clearly maintaining lines of attribution. This work presents a functional prototype of a system to integrate Digital Object Identifiers (DOI) and a standardized metadata schema into a XNAT-based repository workflow, allowing for identification of data at both the project and image level. These item and source level identifiers allow any newly defined combination of images, from any number of projects, to be tagged with a new group-level DOI that automatically inherits the individual attributes and provenance information of its constituent parts. This system enables the tracking of data reuse down to the level of individual images. The implementation of this type of data identification system would impact researchers and data creators, data hosting facilities, and data publishers, but the benefit of having widely accepted standards for data identification and attribution would go far toward making data citation practical and advantageous.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 4 2013-10-01 2013-10-01 false Inspection of switches, track crossings, and lift... TRANSPORTATION TRACK SAFETY STANDARDS Inspection § 213.235 Inspection of switches, track crossings, and lift rail... section, each switch, turnout, track crossing, and moveable bridge lift rail assembly or other transition...
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 4 2014-10-01 2014-10-01 false Inspection of switches, track crossings, and lift... TRANSPORTATION TRACK SAFETY STANDARDS Inspection § 213.235 Inspection of switches, track crossings, and lift rail... section, each switch, turnout, track crossing, and moveable bridge lift rail assembly or other transition...
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 4 2012-10-01 2012-10-01 false Inspection of switches, track crossings, and lift... TRANSPORTATION TRACK SAFETY STANDARDS Inspection § 213.235 Inspection of switches, track crossings, and lift rail... section, each switch, turnout, track crossing, and moveable bridge lift rail assembly or other transition...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Inspection of switches, track crossings, and lift... TRANSPORTATION TRACK SAFETY STANDARDS Inspection § 213.235 Inspection of switches, track crossings, and lift rail... section, each switch, turnout, track crossing, and moveable bridge lift rail assembly or other transition...
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Inspection of switches, track crossings, and lift... TRANSPORTATION TRACK SAFETY STANDARDS Inspection § 213.235 Inspection of switches, track crossings, and lift rail... section, each switch, turnout, track crossing, and moveable bridge lift rail assembly or other transition...
The Habituation/Cross-Habituation Test Revisited: Guidance from Sniffing and Video Tracking
Coronas-Samano, G.; Ivanova, A. V.
2016-01-01
The habituation/cross-habituation test (HaXha) is a spontaneous odor discrimination task that has been used for many decades to evaluate olfactory function in animals. Animals are presented repeatedly with the same odorant after which a new odorant is introduced. The time the animal explores the odor object is measured. An animal is considered to cross-habituate during the novel stimulus trial when the exploration time is higher than the prior trial and indicates the degree of olfactory patency. On the other hand, habituation across the repeated trials involves decreased exploration time and is related to memory patency, especially at long intervals. Classically exploration is timed using a stopwatch when the animal is within 2 cm of the object and aimed toward it. These criteria are intuitive, but it is unclear how they relate to olfactory exploration, that is, sniffing. We used video tracking combined with plethysmography to improve accuracy, avoid observer bias, and propose more robust criteria for exploratory scoring when sniff measures are not available. We also demonstrate that sniff rate combined with proximity is the most direct measure of odorant exploration and provide a robust and sensitive criterion. PMID:27516910
An Integrative Account of Constraints on Cross-Situational Learning
Yurovsky, Daniel; Frank, Michael C.
2015-01-01
Word-object co-occurrence statistics are a powerful information source for vocabulary learning, but there is considerable debate about how learners actually use them. While some theories hold that learners accumulate graded, statistical evidence about multiple referents for each word, others suggest that they track only a single candidate referent. In two large-scale experiments, we show that neither account is sufficient: Cross-situational learning involves elements of both. Further, the empirical data are captured by a computational model that formalizes how memory and attention interact with co-occurrence tracking. Together, the data and model unify opposing positions in a complex debate and underscore the value of understanding the interaction between computational and algorithmic levels of explanation. PMID:26302052
The company objects keep: Linking referents together during cross-situational word learning.
Zettersten, Martin; Wojcik, Erica; Benitez, Viridiana L; Saffran, Jenny
2018-04-01
Learning the meanings of words involves not only linking individual words to referents but also building a network of connections among entities in the world, concepts, and words. Previous studies reveal that infants and adults track the statistical co-occurrence of labels and objects across multiple ambiguous training instances to learn words. However, it is less clear whether, given distributional or attentional cues, learners also encode associations amongst the novel objects. We investigated the consequences of two types of cues that highlighted object-object links in a cross-situational word learning task: distributional structure - how frequently the referents of novel words occurred together - and visual context - whether the referents were seen on matching backgrounds. Across three experiments, we found that in addition to learning novel words, adults formed connections between frequently co-occurring objects. These findings indicate that learners exploit statistical regularities to form multiple types of associations during word learning.
An approach to ground based space surveillance of geostationary on-orbit servicing operations
NASA Astrophysics Data System (ADS)
Scott, Robert (Lauchie); Ellery, Alex
2015-07-01
On Orbit Servicing (OOS) is a class of dual-use robotic space missions that could potentially extend the life of orbiting satellites by fuel replenishment, repair, inspection, orbital maintenance or satellite repurposing, and possibly reduce the rate of space debris generation. OOS performed in geostationary orbit poses a unique challenge for the optical space surveillance community. Both satellites would be performing proximity operations in tight formation flight with separations less than 500 m making atmospheric seeing (turbulence) a challenge to resolving a geostationary satellite pair when viewed from the ground. The two objects would appear merged in an image as the resolving power of the telescope and detector, coupled with atmospheric seeing, limits the ability to resolve the two objects. This poses an issue for obtaining orbital data for conjunction flight safety or, in matters pertaining to space security, inferring the intent and trajectory of an unexpected object perched very close to one's satellite asset on orbit. In order to overcome this problem speckle interferometry using a cross spectrum approach is examined as a means to optically resolve the client and servicer's relative positions to enable a means to perform relative orbit determination of the two spacecraft. This paper explores cases where client and servicing satellites are in unforced relative motion flight and examines the observability of the objects. Tools are described that exploit cross-spectrum speckle interferometry to (1) determine the presence of a secondary in the vicinity of the client satellite and (2) estimate the servicing satellite's motion relative to the client. Experimental observations performed with the Mont Mégantic 1.6 m telescope on co-located geostationary satellites (acting as OOS proxy objects) are described. Apparent angular separations between Anik G1 and Anik F1R from 5 to 1 arcsec were observed as the two satellites appeared to graze one another. Data reduction using differential angular measurements derived from speckle images collected by the 1.6 m telescope produced relative orbit estimates with better than 90 m accuracy in the cross-track and in-track directions but exhibited highly variable behavior in the radial component from 50 to 1800 m. Simulations of synthetic tracking data indicated that the radial component requires approximately six hours of tracking data for an Extended Kalman Filter to converge on an relative orbit estimate with less than 100 m overall uncertainty. The cross-spectrum approach takes advantage of the Fast Fourier Transform (FFT) permitting near real-time estimation of the relative orbit of the two satellites. This also enables the use of relatively larger detector arrays (>106 pixels) helping to ease acquisition process to acquire optical angular data.
Single-camera three-dimensional tracking of natural particulate and zooplankton
NASA Astrophysics Data System (ADS)
Troutman, Valerie A.; Dabiri, John O.
2018-07-01
We develop and characterize an image processing algorithm to adapt single-camera defocusing digital particle image velocimetry (DDPIV) for three-dimensional (3D) particle tracking velocimetry (PTV) of natural particulates, such as those present in the ocean. The conventional DDPIV technique is extended to facilitate tracking of non-uniform, non-spherical particles within a volume depth an order of magnitude larger than current single-camera applications (i.e. 10 cm × 10 cm × 24 cm depth) by a dynamic template matching method. This 2D cross-correlation method does not rely on precise determination of the centroid of the tracked objects. To accommodate the broad range of particle number densities found in natural marine environments, the performance of the measurement technique at higher particle densities has been improved by utilizing the time-history of tracked objects to inform 3D reconstruction. The developed processing algorithms were analyzed using synthetically generated images of flow induced by Hill’s spherical vortex, and the capabilities of the measurement technique were demonstrated empirically through volumetric reconstructions of the 3D trajectories of particles and highly non-spherical, 5 mm zooplankton.
USDA-ARS?s Scientific Manuscript database
Objective - To develop a noninvasive biomarker based Mycobacterium bovis specific detection system to track infection in domestic and wild animals. Design – Experimental longitudinal study for discovery and cross sectional design for validation Animals - Yearling white-tailed deer fawns (n=8) were ...
Gjersoe, Nathalia L.; Newman, George E.; Chituc, Vladimir; Hood, Bruce
2014-01-01
The current studies examine how valuation of authentic items varies as a function of culture. We find that U.S. respondents value authentic items associated with individual persons (a sweater or an artwork) more than Indian respondents, but that both cultures value authentic objects not associated with persons (a dinosaur bone or a moon rock) equally. These differences cannot be attributed to more general cultural differences in the value assigned to authenticity. Rather, the results support the hypothesis that individualistic cultures place a greater value on objects associated with unique persons and in so doing, offer the first evidence for how valuation of certain authentic items may vary cross-culturally. PMID:24658437
Gjersoe, Nathalia L; Newman, George E; Chituc, Vladimir; Hood, Bruce
2014-01-01
The current studies examine how valuation of authentic items varies as a function of culture. We find that U.S. respondents value authentic items associated with individual persons (a sweater or an artwork) more than Indian respondents, but that both cultures value authentic objects not associated with persons (a dinosaur bone or a moon rock) equally. These differences cannot be attributed to more general cultural differences in the value assigned to authenticity. Rather, the results support the hypothesis that individualistic cultures place a greater value on objects associated with unique persons and in so doing, offer the first evidence for how valuation of certain authentic items may vary cross-culturally.
Tea Derived Galloylated Polyphenols Cross-Link Purified Gastrointestinal Mucins
Georgiades, Pantelis; Pudney, Paul D. A.; Rogers, Sarah; Thornton, David J.; Waigh, Thomas A.
2014-01-01
Polyphenols derived from tea are thought to be important for human health. We show using a combination of particle tracking microrheology and small-angle neutron scattering that polyphenols acts as cross-linkers for purified gastrointestinal mucin, derived from the stomach and the duodenum. Both naturally derived purified polyphenols, and green and black tea extracts are shown to act as cross-linkers. The main active cross-linking component is found to be the galloylated forms of catechins. The viscosity, elasticity and relaxation time of the mucin solutions experience an order of magnitude change in value upon addition of the polyphenol cross-linkers. Similarly small-angle neutron scattering experiments demonstrate a sol-gel transition with the addition of polyphenols, with a large increase in the scattering at low angles, which is attributed to the formation of large scale (>10 nm) heterogeneities during gelation. Cross-linking of mucins by polyphenols is thus expected to have an impact on the physicochemical environment of both the stomach and duodenum; polyphenols are expected to modulate the barrier properties of mucus, nutrient absorption through mucus and the viscoelastic microenvironments of intestinal bacteria. PMID:25162539
Conjunction Assessment Late-Notice High-Interest Event Investigation: Space Weather Aspects
NASA Technical Reports Server (NTRS)
Pachura, D.; Hejduk, M. D.
2016-01-01
Late-notice events usually driven by large changes in primary (protected) object or secondary object state. Main parameter to represent size of state change is component position difference divided by associated standard deviation (epsilon divided by sigma) from covariance. Investigation determined actual frequency of large state changes, in both individual and combined states. Compared them to theoretically expected frequencies. Found that large changes ( (epsilon divided by sigma) is greater than 3) in individual object states occur much more frequently than theory dictates. Effect is less pronounced in radial components and in events with probability of collision (Pc) greater than 1 (sup -5) (1e-5). Found combined state matched much closer to theoretical expectation, especially for radial and cross-track. In-track is expected to be the most vulnerable to modeling errors, so not surprising that non-compliance largest in this component.
Robinson, Mike J F; Anselme, Patrick; Suchomel, Kristen; Berridge, Kent C
2015-08-01
Amphetamine and stress can sensitize mesolimbic dopamine-related systems. In Pavlovian autoshaping, repeated exposure to uncertainty of reward prediction can enhance motivated sign-tracking or attraction to a discrete reward-predicting cue (lever-conditioned stimulus; CS+), as well as produce cross-sensitization to amphetamine. However, it remains unknown how amphetamine sensitization or repeated restraint stress interact with uncertainty in controlling CS+ incentive salience attribution reflected in sign-tracking. Here rats were tested in 3 successive phases. First, different groups underwent either induction of amphetamine sensitization or repeated restraint stress, or else were not sensitized or stressed as control groups (either saline injections only, or no stress or injection at all). All next received Pavlovian autoshaping training under either certainty conditions (100% CS-UCS association) or uncertainty conditions (50% CS-UCS association and uncertain reward magnitude). During training, rats were assessed for sign-tracking to the CS+ lever versus goal-tracking to the sucrose dish. Finally, all groups were tested for psychomotor sensitization of locomotion revealed by an amphetamine challenge. Our results confirm that reward uncertainty enhanced sign-tracking attraction toward the predictive CS+ lever, at the expense of goal-tracking. We also reported that amphetamine sensitization promoted sign-tracking even in rats trained under CS-UCS certainty conditions, raising them to sign-tracking levels equivalent to the uncertainty group. Combining amphetamine sensitization and uncertainty conditions did not add together to elevate sign-tracking further above the relatively high levels induced by either manipulation alone. In contrast, repeated restraint stress enhanced subsequent amphetamine-elicited locomotion, but did not enhance CS+ attraction. (c) 2015 APA, all rights reserved).
Robinson, Mike J.F.; Anselme, Patrick; Suchomel, Kristen; Berridge, Kent C.
2015-01-01
Amphetamine and stress can sensitize mesolimbic dopamine-related systems. In Pavlovian autoshaping, repeated exposure to uncertainty of reward prediction can enhance motivated sign-tracking or attraction to a discrete reward-predicting cue (lever CS+), as well as produce cross-sensitization to amphetamine. However, it remains unknown how amphetamine-sensitization or repeated restraint stress interact with uncertainty in controlling CS+ incentive salience attribution reflected in sign-tracking. Here rats were tested in three successive phases. First, different groups underwent either induction of amphetamine sensitization or repeated restraint stress, or else were not sensitized or stressed as control groups (either saline injections only, or no stress or injection at all). All next received Pavlovian autoshaping training under either certainty conditions (100% CS-UCS association) or uncertainty conditions (50% CS-UCS association and uncertain reward magnitude). During training, rats were assessed for sign-tracking to the lever CS+ versus goal-tracking to the sucrose dish. Finally, all groups were tested for psychomotor sensitization of locomotion revealed by an amphetamine challenge. Our results confirm that reward uncertainty enhanced sign-tracking attraction toward the predictive CS+ lever, at the expense of goal-tracking. We also report that amphetamine sensitization promoted sign-tracking even in rats trained under CS-UCS certainty conditions, raising them to sign-tracking levels equivalent to the uncertainty group. Combining amphetamine sensitization and uncertainty conditions together did not add together to elevate sign-tracking further above the relatively high levels induced by either manipulation alone. In contrast, repeated restraint stress enhanced subsequent amphetamine-elicited locomotion, but did not enhance CS+ attraction. PMID:26076340
Single track effects, Biostack and risk assessment
NASA Technical Reports Server (NTRS)
Curtis, S. B.; Chatterjee, A. (Principal Investigator)
1994-01-01
The scientific career of Prof. Bucker has spanned a very exciting period in the fledgling science of Space Radiation Biology. The capability for placing biological objects in space was developed, and the methods for properly packaging, retrieving and analyzing them were worked out. Meaningful results on the effects of radiation were obtained for the first time. In fact, many of the successful techniques and methodologies for handling biological samples were developed in Prof. Bucker's laboratories, as attested by the extensive Biostack program. He was the first to suggest and successfully carry out experiments in space directly aimed at measuring effects of single tracks of high-energy heavy galactic cosmic rays by specifically identifying whether or not the object had been hit by a heavy particle track. Because the "hit" frequencies of heavy galactic cosmic rays to cell nuclei in the bodies of space travelers will be low, it is expected that any effects to humans on the cellular level will be dominated by single-track cell traversals. This includes the most important generally recognized late effect of space radiation exposure: radiation-induced cancer. This paper addresses the single-track nature of the space radiation environment, and points out the importance of single "hits" in the evaluation of radiation risk for long-term missions occurring outside the earth's magnetic field. A short review is made of biological objects found to show increased effects when "hit" by a single heavy charged-particle in space. A brief discussion is given of the most provocative results from the bacterial spore Bacillus subtilis: experimental evidence that tracks can affect biological systems at much larger distances from the trajectory than previously suspected, and that the resultant inactivation cross section in space calculated for this system is very large. When taken at face value, the implication of these results, when compared to those from experiments performed at ground-based accelerators with beams at low energies in the same LET range, is that high-energy particles can exert their influence a surprising distance from their trajectory and the inactivation cross sections are some 20 times larger than expected. Clearly, beams from high-energy heavy-ion accelerators should be used to confirm these results. For those end points that can also be caused by low-LET beams such as high-energy protons, it is important to measure their action cross sections as well. The ratio of the cross sections for a high-LET beam to that of a low-LET beam is an interesting experimental ratio and, we suggest, of more intrinsic interest than the RBE (Relative Biological Effectiveness). It is a measure of the "biological" importance of one particle type relative to another particle type. This ratio will be introduced and given the name RPPE (Relative Per Particle Effectiveness). Values of RPPE have appeared in the literature and will be discussed. A rather well-known value of this quantity (13,520) has been suggested for the RPPE of high-energy iron ions to high-energy protons. This value was suggested by Letaw et al. Nature 330, 709-710 (1987)] we will call it the Letaw limit. It will be discussed in terms of the importance of the heavy-ion component vs light-ion component of the galactic cosmic rays. It is also pointed out, however, that there may be unique effects from single tracks of heavy ions that do not occur from light-ion tracks. For such effects, the concepts of both RBE and RPPE lose their meaning.
Wakefield, Melanie; Coomber, Kerri; Zacher, Meghan; Durkin, Sarah; Brennan, Emily; Scollo, Michelle
2015-01-01
Background We assessed whether the Australian plain packs with larger graphic health warnings (GHWs) achieved three specific objectives of reducing the appeal of tobacco, increasing health warning effectiveness and reducing the ability of packaging to mislead about smoking harms. Methods We compared responses from continuous cross-sectional telephone surveys of n=2176 cigarette smokers during pre-plain packaging (April–September 2012, pre-PP) with n=759 surveyed in the transition period (October–November 2012) and n=4240 during the first year of implementation (December 2012–November 2013, PP year 1), using multivariate logistic regression analyses. Results From pre-PP to PP year 1, more smokers disliked their pack (p<0.001), perceived lower pack appeal (p<0.001), lower cigarette quality (p<0.001), lower satisfaction (p<0.001) and lower value (p<0.001) and disagreed brands differed in prestige (p=0.003). There was no change in perceived differences in taste of different brands. More smokers noticed GHWs (p<0.001), attributed much motivation to quit to GHWs (p<0.001), avoided specific GHWs when purchasing (p<0.001), and covered packs (p<0.001), with no change in perceived exaggeration of harms. PP year 1 saw an increased proportion believing that brands do not differ in harmfulness (p=0.004), but no change in the belief that variants do not differ in strength or the perceived harmfulness of cigarettes compared with a year ago. Interactions signified greater change for four outcomes assessing aspects of appeal among young adults and two appeal outcomes among mid-aged adults. Conclusions The specific objectives of plain packaging were achieved and generally sustained among adult smokers up to 12 months after implementation. PMID:28407606
Genomes as geography: using GIS technology to build interactive genome feature maps
Dolan, Mary E; Holden, Constance C; Beard, M Kate; Bult, Carol J
2006-01-01
Background Many commonly used genome browsers display sequence annotations and related attributes as horizontal data tracks that can be toggled on and off according to user preferences. Most genome browsers use only simple keyword searches and limit the display of detailed annotations to one chromosomal region of the genome at a time. We have employed concepts, methodologies, and tools that were developed for the display of geographic data to develop a Genome Spatial Information System (GenoSIS) for displaying genomes spatially, and interacting with genome annotations and related attribute data. In contrast to the paradigm of horizontally stacked data tracks used by most genome browsers, GenoSIS uses the concept of registered spatial layers composed of spatial objects for integrated display of diverse data. In addition to basic keyword searches, GenoSIS supports complex queries, including spatial queries, and dynamically generates genome maps. Our adaptation of the geographic information system (GIS) model in a genome context supports spatial representation of genome features at multiple scales with a versatile and expressive query capability beyond that supported by existing genome browsers. Results We implemented an interactive genome sequence feature map for the mouse genome in GenoSIS, an application that uses ArcGIS, a commercially available GIS software system. The genome features and their attributes are represented as spatial objects and data layers that can be toggled on and off according to user preferences or displayed selectively in response to user queries. GenoSIS supports the generation of custom genome maps in response to complex queries about genome features based on both their attributes and locations. Our example application of GenoSIS to the mouse genome demonstrates the powerful visualization and query capability of mature GIS technology applied in a novel domain. Conclusion Mapping tools developed specifically for geographic data can be exploited to display, explore and interact with genome data. The approach we describe here is organism independent and is equally useful for linear and circular chromosomes. One of the unique capabilities of GenoSIS compared to existing genome browsers is the capacity to generate genome feature maps dynamically in response to complex attribute and spatial queries. PMID:16984652
Physician Service Attribution Methods for Examining Provision of Low-Value Care
Chang, Eva; Buist, Diana SM; Handley, Matthew; Pardee, Roy; Gundersen, Gabrielle; Reid, Robert J.
2016-01-01
Objectives: There has been significant research on provider attribution for quality and cost. Low-value care is an area of heightened focus, with little of the focus being on measurement; a key methodological decision is how to attribute delivered services and procedures. We illustrate the difference in relative and absolute physician- and panel-attributed services and procedures using overuse in cervical cancer screening. Study Design: A retrospective, cross-sectional study in an integrated health care system. Methods: We used 2013 physician-level data from Group Health Cooperative to calculate two utilization attributions: (1) panel attribution with the procedure assigned to the physician’s predetermined panel, regardless of who performed the procedure; and (2) physician attribution with the procedure assigned to the performing physician. We calculated the percentage of low-value cervical cancer screening tests and ranked physicians within the clinic using the two utilization attribution methods. Results: The percentage of low-value cervical cancer screening varied substantially between physician and panel attributions. Across the whole delivery system, median panel- and physician-attributed percentages were 15 percent and 10 percent, respectively. Among sampled clinics, panel-attributed percentages ranged between 10 percent and 17 percent, and physician-attributed percentages ranged between 9 percent and 13 percent. Within a clinic, median panel-attributed screening percentage was 17 percent (range 0 percent–27 percent) and physician-attributed percentage was 11 percent (range 0 percent–24 percent); physician rank varied by attribution method. Conclusions: The attribution method is an important methodological decision when developing low-value care measures since measures may ultimately have an impact on national benchmarking and quality scores. Cross-organizational dialogue and transparency in low-value care measurement will become increasingly important for all stakeholders. PMID:28203612
Similar resilience attributes in lakes with different management practices
Baho, Didier L.; Drakare, Stina; Johnson, Richard K.; Allen, Craig R.; Angeler, David G.
2014-01-01
Liming has been used extensively in Scandinavia and elsewhere since the 1970s to counteract the negative effects of acidification. Communities in limed lakes usually return to acidified conditions once liming is discontinued, suggesting that liming is unlikely to shift acidified lakes to a state equivalent to pre-acidification conditions that requires no further management intervention. While this suggests a low resilience of limed lakes, attributes that confer resilience have not been assessed, limiting our understanding of the efficiency of costly management programs. In this study, we assessed community metrics (diversity, richness, evenness, biovolume), multivariate community structure and the relative resilience of phytoplankton in limed, acidified and circum-neutral lakes from 1997 to 2009, using multivariate time series modeling. We identified dominant temporal frequencies in the data, allowing us to track community change at distinct temporal scales. We assessed two attributes of relative resilience (cross-scale and within-scale structure) of the phytoplankton communities, based on the fluctuation frequency patterns identified. We also assessed species with stochastic temporal dynamics. Liming increased phytoplankton diversity and richness; however, multivariate community structure differed in limed relative to acidified and circum-neutral lakes. Cross-scale and within-scale attributes of resilience were similar across all lakes studied but the contribution of those species exhibiting stochastic dynamics was higher in the acidified and limed compared to circum-neutral lakes. From a resilience perspective, our results suggest that limed lakes comprise a particular condition of an acidified lake state. This explains why liming does not move acidified lakes out of a “degraded” basin of attraction. In addition, our study demonstrates the potential of time series modeling to assess the efficiency of restoration and management outcomes through quantification of the attributes contributing to resilience in ecosystems.
Effects of thermal and electrical stressing on the breakdown behavior of space wiring
NASA Technical Reports Server (NTRS)
Hammoud, Ahmad; Stavnes, Mark; Suthar, Jayant; Laghari, Javaid
1995-01-01
Several failures in the electrical wiring systems of many aircraft and space vehicles have been attributed to arc tracking and damaged insulation. In some instances, these failures proved to be very costly as they have led to the loss of many aircraft and imperilment of space missions. Efforts are currently underway to develop lightweight, reliable, and arc track resistant wiring for aerospace applications. In this work, six wiring constructions were evaluated in terms of their breakdown behavior as a function of temperature. These hybrid constructions employed insulation consisting of Kapton, Teflon, and cross-linked Tefzel. The properties investigated included the 400 Hz AC dielectric strength at ambient and 200 C, and the lifetime at high temperature with an applied bias of 40, 60, and 80% of breakdown voltage level. The results obtained are discussed, and conclusions are made concerning the suitability of the wiring constructions investigated for aerospace applications.
Effects of thermal and electrical stressing on the breakdown behavior of space wiring
NASA Astrophysics Data System (ADS)
Hammoud, Ahmad; Stavnes, Mark; Suthar, Jayant; Laghari, Javaid
1995-06-01
Several failures in the electrical wiring systems of many aircraft and space vehicles have been attributed to arc tracking and damaged insulation. In some instances, these failures proved to be very costly as they have led to the loss of many aircraft and imperilment of space missions. Efforts are currently underway to develop lightweight, reliable, and arc track resistant wiring for aerospace applications. In this work, six wiring constructions were evaluated in terms of their breakdown behavior as a function of temperature. These hybrid constructions employed insulation consisting of Kapton, Teflon, and cross-linked Tefzel. The properties investigated included the 400 Hz AC dielectric strength at ambient and 200 C, and the lifetime at high temperature with an applied bias of 40, 60, and 80% of breakdown voltage level. The results obtained are discussed, and conclusions are made concerning the suitability of the wiring constructions investigated for aerospace applications.
Inter-individual variability of stone marten behavioral responses to a highway.
Ascensão, Fernando; Grilo, Clara; LaPoint, Scott; Tracey, Jeff; Clevenger, Anthony P; Santos-Reis, Margarida
2014-01-01
Efforts to reduce the negative impacts of roads on wildlife may be hindered if individuals within the population vary widely in their responses to roads and mitigation strategies ignore this variability. This knowledge is particularly important for medium-sized carnivores as they are vulnerable to road mortality, while also known to use available road passages (e.g., drainage culverts) for safely crossing highways. Our goal in this study was to assess whether this apparently contradictory pattern of high road-kill numbers associated with a regular use of road passages is attributable to the variation in behavioral responses toward the highway between individuals. We investigated the responses of seven radio-tracked stone martens (Martes foina) to a highway by measuring their utilization distribution, response turning angles and highway crossing patterns. We compared the observed responses to simulated movement parameterized by the observed space use and movement characteristics of each individual, but naïve to the presence of the highway. Our results suggested that martens demonstrate a diversity of responses to the highway, including attraction, indifference, or avoidance. Martens also varied in their highway crossing patterns, with some crossing repeatedly at the same location (often coincident with highway passages). We suspect that the response variability derives from the individual's familiarity of the landscape, including their awareness of highway passage locations. Because of these variable yet potentially attributable responses, we support the use of exclusionary fencing to guide transient (e.g., dispersers) individuals to existing passages to reduce the road-kill risk.
Inter-Individual Variability of Stone Marten Behavioral Responses to a Highway
Ascensão, Fernando; Grilo, Clara; LaPoint, Scott; Tracey, Jeff; Clevenger, Anthony P.; Santos-Reis, Margarida
2014-01-01
Efforts to reduce the negative impacts of roads on wildlife may be hindered if individuals within the population vary widely in their responses to roads and mitigation strategies ignore this variability. This knowledge is particularly important for medium-sized carnivores as they are vulnerable to road mortality, while also known to use available road passages (e.g., drainage culverts) for safely crossing highways. Our goal in this study was to assess whether this apparently contradictory pattern of high road-kill numbers associated with a regular use of road passages is attributable to the variation in behavioral responses toward the highway between individuals. We investigated the responses of seven radio-tracked stone martens (Martes foina) to a highway by measuring their utilization distribution, response turning angles and highway crossing patterns. We compared the observed responses to simulated movement parameterized by the observed space use and movement characteristics of each individual, but naïve to the presence of the highway. Our results suggested that martens demonstrate a diversity of responses to the highway, including attraction, indifference, or avoidance. Martens also varied in their highway crossing patterns, with some crossing repeatedly at the same location (often coincident with highway passages). We suspect that the response variability derives from the individual's familiarity of the landscape, including their awareness of highway passage locations. Because of these variable yet potentially attributable responses, we support the use of exclusionary fencing to guide transient (e.g., dispersers) individuals to existing passages to reduce the road-kill risk. PMID:25072639
Cross-Sensory Correspondences: Heaviness is Dark and Low-Pitched.
Walker, Peter; Scallon, Gabrielle; Francis, Brian
2017-07-01
Everyday language reveals how stimuli encoded in one sensory feature domain can possess qualities normally associated with a different domain (e.g., higher pitch sounds are bright, light in weight, sharp, and thin). Such cross-sensory associations appear to reflect crosstalk among aligned (corresponding) feature dimensions, including brightness, heaviness, and sharpness. Evidence for heaviness being one such dimension is very limited, with heaviness appearing primarily as a verbal associate of other feature contrasts (e.g., darker objects and lower pitch sounds are heavier than their opposites). Given the presumed bidirectionality of the crosstalk between corresponding dimensions, heaviness should itself induce the cross-sensory associations observed elsewhere, including with brightness and pitch. Taking care to dissociate effects arising from the size and mass of an object, this is confirmed. When hidden objects varying independently in size and mass are lifted, objects that feel heavier are judged to be darker and to make lower pitch sounds than objects feeling less heavy. These judgements track the changes in perceived heaviness induced by the size-weight illusion. The potential involvement of language, natural scene statistics, and Bayesian processes in correspondences, and the effects they induce, is considered.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-07
... and obtaining input from supply chain partners on attributes and standards for the identification... protecting public health by securing the drug supply chain against the introduction of counterfeit and other... supply chain and protecting consumers from the threats posed by counterfeit drugs. The ability to track...
Zhang, Casper J P; Barnett, Anthony; Sit, Cindy H P; Lai, Poh-chin; Johnston, Janice M; Lee, Ruby S Y; Cerin, Ester
2018-01-01
Objectives This study aimed to examine the associations between objectively assessed neighbourhood environmental attributes and depressive symptoms in Hong Kong Chinese older adults and the moderating effects of neighbourhood environmental attributes on the associations between living arrangements and depressive symptoms. Design Cross-sectional observational study. Setting Hong Kong. Participants 909 Hong Kong Chinese community dwellers aged 65+ years residing in preselected areas stratified by walkability and socioeconomic status. Exposure and outcome measures Attributes of participants’ neighbourhood environment were objectively assessed using geographic information systems and environmental audits. Depressive symptoms were measured using the Geriatric Depression Scale. Results Overall, pedestrian infrastructure (OR=1.025; P=0.008), connectivity (OR=1.039; P=0.002) and prevalence of public transport stops (OR=1.056; P=0.012) were positively associated with the odds of reporting depressive symptoms. Older adults living alone were at higher risk of reporting any depressive symptoms than those living with others (OR=1.497; P=0.039). This association was moderated by neighbourhood crowdedness, perceptible pollution, access to destinations and presence of people. Residing in neighbourhoods with lower levels of these attributes was associated with increased deleterious effects of living alone. Living in neighbourhoods with lower public transport density also increased the deleterious effects of living alone on the number of depressive symptoms. Those living alone and residing in neighbourhoods with higher levels of connectivity tended to report more depressive symptoms than their counterparts. Conclusions The level of access to destinations and social networks across Hong Kong may be sufficiently high to reduce the risk of depressive symptoms in older adults. Yet, exposure to extreme levels of public transport density and associated traffic volumes may increase the risk of depressive symptoms. The provision of good access to a variety of destinations, public transport and public open spaces for socialising in the neighbourhood may help reduce the risk of depressive symptoms in older adults who live alone. PMID:29581207
Tracking multiple objects is limited only by object spacing, not by speed, time, or capacity.
Franconeri, S L; Jonathan, S V; Scimeca, J M
2010-07-01
In dealing with a dynamic world, people have the ability to maintain selective attention on a subset of moving objects in the environment. Performance in such multiple-object tracking is limited by three primary factors-the number of objects that one can track, the speed at which one can track them, and how close together they can be. We argue that this last limit, of object spacing, is the root cause of all performance constraints in multiple-object tracking. In two experiments, we found that as long as the distribution of object spacing is held constant, tracking performance is unaffected by large changes in object speed and tracking time. These results suggest that barring object-spacing constraints, people could reliably track an unlimited number of objects as fast as they could track a single object.
Interaction of railway vehicles with track in cross-winds
NASA Astrophysics Data System (ADS)
Xu, Y. L.; Ding, Q. S.
2006-04-01
This paper presents a framework for simulating railway vehicle and track interaction in cross-wind. Each 4-axle vehicle in a train is modeled by a 27-degree-of-freedom dynamic system. Two parallel rails of a track are modeled as two continuous beams supported by a discrete-elastic foundation of three layers with sleepers and ballasts included. The vehicle subsystem and the track subsystem are coupled through contacts between wheels and rails based on contact theory. Vertical and lateral rail irregularities simulated using an inverse Fourier transform are also taken into consideration. The simulation of steady and unsteady aerodynamic forces on a moving railway vehicle in cross-wind is then discussed in the time domain. The Hilber Hughes Taylor α-method is employed to solve the nonlinear equations of motion of coupled vehicle and track systems in cross-wind. The proposed framework is finally applied to a railway vehicle running on a straight track substructure in cross-wind. The safety and comfort performance of the moving vehicle in cross-wind are discussed. The results demonstrate that the proposed framework and the associated computer program can be used to investigate interaction problems of railway vehicles with track in cross-wind.
Helble, Tyler A; Henderson, E Elizabeth; Ierley, Glenn R; Martin, Stephen W
2016-12-01
Time difference of arrival methods for acoustically localizing multiple marine mammals have been applied to recorded data from the Navy's Pacific Missile Range Facility in order to localize and track calls attributed to Bryde's whales. Data were recorded during the months of August-October 2014, and 17 individual tracks were identified. Call characteristics were compared to other Bryde's whale vocalizations from the Pacific Ocean, and locations of the recorded signals were compared to published visual sightings of Bryde's whales in the Hawaiian archipelago. Track kinematic information, such as swim speeds, bearing information, track duration, and directivity, was recorded for the species. The intercall interval was also established for most of the tracks, providing cue rate information for this species that may be useful for future acoustic density estimate calculations.
Vehicle track interaction safety standards
DOT National Transportation Integrated Search
2014-04-02
Vehicle/Track Interaction (VTI) Safety Standards aim to : reduce the risk of derailments and other accidents attributable : to the dynamic interaction between moving vehicles and the : track over which they operate. On March 13, 2013, the Federal : R...
Famulari, Gabriel; Pater, Piotr; Enger, Shirin A
2017-07-07
The aim of this study was to calculate microdosimetric distributions for low energy electrons simulated using the Monte Carlo track structure code Geant4-DNA. Tracks for monoenergetic electrons with kinetic energies ranging from 100 eV to 1 MeV were simulated in an infinite spherical water phantom using the Geant4-DNA extension included in Geant4 toolkit version 10.2 (patch 02). The microdosimetric distributions were obtained through random sampling of transfer points and overlaying scoring volumes within the associated volume of the tracks. Relative frequency distributions of energy deposition f(>E)/f(>0) and dose mean lineal energy ([Formula: see text]) values were calculated in nanometer-sized spherical and cylindrical targets. The effects of scoring volume and scoring techniques were examined. The results were compared with published data generated using MOCA8B and KURBUC. Geant4-DNA produces a lower frequency of higher energy deposits than MOCA8B. The [Formula: see text] values calculated with Geant4-DNA are smaller than those calculated using MOCA8B and KURBUC. The differences are mainly due to the lower ionization and excitation cross sections of Geant4-DNA for low energy electrons. To a lesser extent, discrepancies can also be attributed to the implementation in this study of a new and fast scoring technique that differs from that used in previous studies. For the same mean chord length ([Formula: see text]), the [Formula: see text] calculated in cylindrical volumes are larger than those calculated in spherical volumes. The discrepancies due to cross sections and scoring geometries increase with decreasing scoring site dimensions. A new set of [Formula: see text] values has been presented for monoenergetic electrons using a fast track sampling algorithm and the most recent physics models implemented in Geant4-DNA. This dataset can be combined with primary electron spectra to predict the radiation quality of photon and electron beams.
Anderson, Rachel I; Bush, Peter C; Spear, Linda P
2013-11-15
Cues repeatedly paired with rewards often themselves become imbued with enhanced motivational value, or incentive salience. During Pavlovian conditioned approach procedures, a cue repeatedly preceding reward delivery often elicits conditioned responses at either the reward delivery location ("goal-tracking") or the cue itself ("sign-tracking"). Sign-tracking behavior is thought to reflect the individual differences in attribution of incentive salience to reward-paired cues that may contribute to addiction vulnerability. Adolescent rats typically demonstrate less sign-tracking behavior than adult rats, a surprising finding given that adolescence is hypothesized to be a time of heightened addiction vulnerability. Given evidence that adult sign-tracking behavior can be influenced by environmental conditions, the present study compared the effects of isolate housing and food deprivation on expression of sign-tacking and goal-tracking behavior in adolescent and adult male rats across eight days of a Pavlovian conditioned approach procedure. Pair-housed adults exhibited more sign-tracking behavior than pair-housed adolescents; however, this age difference was not apparent in isolate-housed subjects. Adolescents often appeared more sensitive than adults to both food restriction- and isolate housing-induced changes in behavior, with food restriction promoting an increase in sign-tracking among isolate-housed adolescents and an increase in goal-tracking among pair-housed adolescents. For adults, food restriction resulted in a modest increase in overall expression of both sign- and goal-tracking behavior. To the extent that sign-tracking behavior reflects attribution of incentive salience to reward-paired cues, results from the present study provide evidence that reactivity to rewards during adolescence is strongly related to the nature of the surrounding environment. Copyright © 2013 Elsevier B.V. All rights reserved.
Effect of cross-correlation on track-to-track fusion
NASA Astrophysics Data System (ADS)
Saha, Rajat K.
1994-07-01
Since the advent of target tracking systems employing a diverse mixture of sensors, there has been increasing recognition by air defense system planners and other military system analysts of the need to integrate these tracks so that a clear air picture can be obtained in a command center. A popular methodology to achieve this goal is to perform track-to-track fusion, which performs track-to-track association as well as kinematic state vector fusion. This paper seeks to answer analytically the extent of improvement achievable by means of kinetic state vector fusion when the tracks are obtained from dissimilar sensors (e.g., Radar/ESM/IRST/IFF). It is well known that evaluation of the performance of state vector fusion algorithms at steady state must take into account the effects of cross-correlation between eligible tracks introduced by the input noise which, unfortunately, is often neglected because of added computational complexity. In this paper, an expression for the steady-state cross-covariance matrix for a 2D state vector track-to-track fusion is obtained. This matrix is shown to be a function of the parameters of the Kalman filters associated with the candidate tracks being fused. Conditions for positive definiteness of the cross-covariance matrix have been derived and the effect of positive definiteness on performance of track-to-track fusion is also discussed.
Factors Associated with Evaluation of Contraception Options among University Undergraduates
ERIC Educational Resources Information Center
McDermott, Robert J.; Malo, Teri L.; Dodd, Virginia J.; Mayer, Alyssa B.
2013-01-01
The objective of this study was to examine attributes assigned by university undergraduates to 12 contraception options, determine if dimensions used to evaluate options differed for women and men, and assess whether these dimensions have changed over time. This study was cross-sectional and involved a written survey. The sample (N = 792) was…
Integrated cluster management at Manchester
NASA Astrophysics Data System (ADS)
McNab, Andrew; Forti, Alessandra
2012-12-01
We describe an integrated management system using third-party, open source components used in operating a large Tier-2 site for particle physics. This system tracks individual assets and records their attributes such as MAC and IP addresses; derives DNS and DHCP configurations from this database; creates each host's installation and re-configuration scripts; monitors the services on each host according to the records of what should be running; and cross references tickets with asset records and per-asset monitoring pages. In addition, scripts which detect problems and automatically remove hosts record these new states in the database which are available to operators immediately through the same interface as tickets and monitoring.
Chung, L; Chung, S-J
2007-11-01
One of the most important initial steps in exporting a food product to another country from the R&D perspective is to describe and translate the sensory characteristics of a food product appropriately into the language of the target country. The objectives of this study were to describe and compare the sensory characteristics of Korean and Japanese style fermented soybean products, and to cross-culturally compare the lexicons of the identical product generated by the Korean and Japanese panelists. Four types of Korean and 4 types of Japanese style fermented soybean consisting of whole bean type and paste type were analyzed. Ten Korean and 9 Japanese panelists were recruited in Korea. Two separate descriptive analyses were conducted, with the panelists differing in their country of origin. Each group was trained, developed lexicon, and conducted descriptive analysis independently. Analysis of variance and various multivariate analyses were applied to delineate the sensory characteristics of the samples and to compare the cross-cultural differences in the usage of lexicon. The Korean and Japanese panelists generated 48 and 36 sensory attributes, respectively. Cross-cultural consensus was shown for evaluating the whole bean type fermented soybean and white miso, which were relatively distinctive samples. However, for the less distinctive samples, the panelists tend to rate higher in negative attributes for the fermented soybeans that originated from the other country. The Japanese panelists grouped the samples by their country of origin and soy sauce flavor was the main attribute for cross-cultural differentiation. However, the Korean panelists did not make a cross-cultural distinction among the samples.
Self-motion impairs multiple-object tracking.
Thomas, Laura E; Seiffert, Adriane E
2010-10-01
Investigations of multiple-object tracking aim to further our understanding of how people perform common activities such as driving in traffic. However, tracking tasks in the laboratory have overlooked a crucial component of much real-world object tracking: self-motion. We investigated the hypothesis that keeping track of one's own movement impairs the ability to keep track of other moving objects. Participants attempted to track multiple targets while either moving around the tracking area or remaining in a fixed location. Participants' tracking performance was impaired when they moved to a new location during tracking, even when they were passively moved and when they did not see a shift in viewpoint. Self-motion impaired multiple-object tracking in both an immersive virtual environment and a real-world analog, but did not interfere with a difficult non-spatial tracking task. These results suggest that people use a common mechanism to track changes both to the location of moving objects around them and to keep track of their own location. Copyright 2010 Elsevier B.V. All rights reserved.
An assessment of primary care attributes from the perspective of female healthcare users1
Lima, Eliane de Fátima Almeida; Sousa, Ana Inês; Primo, Cândida Caniçali; Leite, Francielie Marabotti Costa; Lima, Rita de Cassia Duarte; Maciel, Ethel Leonor Nóia
2015-01-01
OBJECTIVE: this study sought to assess the quality of the Family Health Strategy (FHS) and investigated the association between primary care attributes (PCAs) and the sociodemographic characteristics of users. METHOD: a total of 215 female FHS users were interviewed for this descriptive and cross-sectional study. The Primary Care Assessment Tool (PCATool), Adult Edition was used, and the results were analyzed using Fisher's exact tests, Pearson's chi-square tests and logistic regressions. RESULTS: the lowest average score corresponded to the dimension "accessibility" (1.80), and the highest score corresponded to "access" (8.76). The results corresponding to the attributes "longitudinality", "coordination", "comprehensiveness", and "orientation" were not significant. No association was found between the participants' sociodemographic characteristics and the essential, derivative, and general attributes (p>0.05). CONCLUSION: several attributes must be improved across all the investigated services from the perspective of female FHS users. PMID:26155006
Analyses of Phase III Dynamic Buckling Tests. Final Report
DOT National Transportation Integrated Search
1990-02-01
Thermal buckling of railroad tracks in the lateral plane is an important problem in the design and maintenance of continuous welded rail (CWR) tracks. The problem is manifested through derailments which are attributable to track buckling, indicating ...
Track Everything: Limiting Prior Knowledge in Online Multi-Object Recognition.
Wong, Sebastien C; Stamatescu, Victor; Gatt, Adam; Kearney, David; Lee, Ivan; McDonnell, Mark D
2017-10-01
This paper addresses the problem of online tracking and classification of multiple objects in an image sequence. Our proposed solution is to first track all objects in the scene without relying on object-specific prior knowledge, which in other systems can take the form of hand-crafted features or user-based track initialization. We then classify the tracked objects with a fast-learning image classifier, that is based on a shallow convolutional neural network architecture and demonstrate that object recognition improves when this is combined with object state information from the tracking algorithm. We argue that by transferring the use of prior knowledge from the detection and tracking stages to the classification stage, we can design a robust, general purpose object recognition system with the ability to detect and track a variety of object types. We describe our biologically inspired implementation, which adaptively learns the shape and motion of tracked objects, and apply it to the Neovision2 Tower benchmark data set, which contains multiple object types. An experimental evaluation demonstrates that our approach is competitive with the state-of-the-art video object recognition systems that do make use of object-specific prior knowledge in detection and tracking, while providing additional practical advantages by virtue of its generality.
The Role of Visual Working Memory in Attentive Tracking of Unique Objects
ERIC Educational Resources Information Center
Makovski, Tal; Jiang, Yuhong V.
2009-01-01
When tracking moving objects in space humans usually attend to the objects' spatial locations and update this information over time. To what extent do surface features assist attentive tracking? In this study we asked participants to track identical or uniquely colored objects. Tracking was enhanced when objects were unique in color. The benefit…
NASA Technical Reports Server (NTRS)
Cambridge, Vivien J.; Magee, Ronald G.
1993-01-01
The method of silhouettes proceeds from the premise that the 3D location and shape of an arbitrary object can be approximated via the cross section of a series of conical volumes whose focal points are arranged at sites surrounding the object; the projection of each conical volume onto a picture plane at each focal point is identical to a projection of the outline of the object onto that picture plane. Attention is presently given to the use of the silhouettes method for gas plume dispersion monitoring through the 3D reconstruction of plumes from imagery acquired at strategically located stations in the plumes' path.
Li, Jia; Xia, Changqun; Chen, Xiaowu
2017-10-12
Image-based salient object detection (SOD) has been extensively studied in past decades. However, video-based SOD is much less explored due to the lack of large-scale video datasets within which salient objects are unambiguously defined and annotated. Toward this end, this paper proposes a video-based SOD dataset that consists of 200 videos. In constructing the dataset, we manually annotate all objects and regions over 7,650 uniformly sampled keyframes and collect the eye-tracking data of 23 subjects who free-view all videos. From the user data, we find that salient objects in a video can be defined as objects that consistently pop-out throughout the video, and objects with such attributes can be unambiguously annotated by combining manually annotated object/region masks with eye-tracking data of multiple subjects. To the best of our knowledge, it is currently the largest dataset for videobased salient object detection. Based on this dataset, this paper proposes an unsupervised baseline approach for video-based SOD by using saliencyguided stacked autoencoders. In the proposed approach, multiple spatiotemporal saliency cues are first extracted at the pixel, superpixel and object levels. With these saliency cues, stacked autoencoders are constructed in an unsupervised manner that automatically infers a saliency score for each pixel by progressively encoding the high-dimensional saliency cues gathered from the pixel and its spatiotemporal neighbors. In experiments, the proposed unsupervised approach is compared with 31 state-of-the-art models on the proposed dataset and outperforms 30 of them, including 19 imagebased classic (unsupervised or non-deep learning) models, six image-based deep learning models, and five video-based unsupervised models. Moreover, benchmarking results show that the proposed dataset is very challenging and has the potential to boost the development of video-based SOD.
Super-resolution imaging applied to moving object tracking
NASA Astrophysics Data System (ADS)
Swalaganata, Galandaru; Ratna Sulistyaningrum, Dwi; Setiyono, Budi
2017-10-01
Moving object tracking in a video is a method used to detect and analyze changes that occur in an object that being observed. Visual quality and the precision of the tracked target are highly wished in modern tracking system. The fact that the tracked object does not always seem clear causes the tracking result less precise. The reasons are low quality video, system noise, small object, and other factors. In order to improve the precision of the tracked object especially for small object, we propose a two step solution that integrates a super-resolution technique into tracking approach. First step is super-resolution imaging applied into frame sequences. This step was done by cropping the frame in several frame or all of frame. Second step is tracking the result of super-resolution images. Super-resolution image is a technique to obtain high-resolution images from low-resolution images. In this research single frame super-resolution technique is proposed for tracking approach. Single frame super-resolution was a kind of super-resolution that it has the advantage of fast computation time. The method used for tracking is Camshift. The advantages of Camshift was simple calculation based on HSV color that use its histogram for some condition and color of the object varies. The computational complexity and large memory requirements required for the implementation of super-resolution and tracking were reduced and the precision of the tracked target was good. Experiment showed that integrate a super-resolution imaging into tracking technique can track the object precisely with various background, shape changes of the object, and in a good light conditions.
Searching for structural medium changes during the 2011 El Hierro (Spain) submarine eruption
NASA Astrophysics Data System (ADS)
Sánchez-Pastor, Pilar S.; Schimmel, Martin; López, Carmen
2017-04-01
Submarine volcanic eruptions are often difficult to study due to their restricted access that usually inhibits direct observations. That happened with the 2011 El Hierro eruption, which is the first eruption that has been tracked in real time in Canary Islands. For instance, despite the real-time tracking it was not possible to determine the exact end of the eruption. Besides, volcanic eruptions involve many dynamic (physical and chemical) processes, which cause structural changes in the surrounding medium that we expect to observe and monitor through passive seismic approaches. The purpose of this study is to detect and analyse these changes as well as to search for precursory signals to the eruption itself using ambient noise auto and cross-correlations. We employ different correlation strategies (classical and phase cross-correlation) and apply them to field data recorded by the IGN network during 2011 and 2012. The different preprocessing and processing steps are tested and compared to better understand the data, to find the robust signatures, and to define a routine work procedure. One of the problems we face is the presence of volcanic tremors, which cause a varying seismic response that we can not attribute to structural changes. So far, structural changes could not be detected unambiguously and we present our ongoing research in this field.
Parenting Attributions and Attitudes in Cross-Cultural Perspective.
Bornstein, Marc H; Putnick, Diane L; Lansford, Jennifer E
2011-07-01
OBJECTIVE: This article used the Parenting Across Cultures Project to evaluate similarities and differences in mean levels and relative agreement between mothers' and fathers' attributions and attitudes in parenting in 9 countries. DESIGN: Mothers and fathers reported their perceptions of causes of successes and failures in caregiving and their progressive versus authoritarian childrearing attitudes. Gender and cultural similarities and differences in parents' attributions and attitudes in 9 countries were analyzed: China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, or the United States. RESULTS: Although mothers and fathers did not differ in any attribution, mothers reported more progressive parenting attitudes and modernity of childrearing attitudes than did fathers, and fathers reported more authoritarian attitudes than did mothers. Country differences also emerged in all attributions and attitudes that were examined. Mothers' and fathers' attributions and their attitudes were moderately correlated, but parenting attitudes were more highly correlated in parents than were attributions. CONCLUSIONS: We draw connections among the findings across the 9 countries and outline implications for understanding similarities and differences in mothers' and fathers' parenting attributions and attitudes.
Parenting Attributions and Attitudes in Cross-Cultural Perspective
Bornstein, Marc H.; Putnick, Diane L.; Lansford, Jennifer E.
2011-01-01
SYNOPSIS Objective This article used the Parenting Across Cultures Project to evaluate similarities and differences in mean levels and relative agreement between mothers’ and fathers’ attributions and attitudes in parenting in 9 countries. Design Mothers and fathers reported their perceptions of causes of successes and failures in caregiving and their progressive versus authoritarian childrearing attitudes. Gender and cultural similarities and differences in parents’ attributions and attitudes in 9 countries were analyzed: China, Colombia, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, or the United States. Results Although mothers and fathers did not differ in any attribution, mothers reported more progressive parenting attitudes and modernity of childrearing attitudes than did fathers, and fathers reported more authoritarian attitudes than did mothers. Country differences also emerged in all attributions and attitudes that were examined. Mothers’ and fathers’ attributions and their attitudes were moderately correlated, but parenting attitudes were more highly correlated in parents than were attributions. Conclusions We draw connections among the findings across the 9 countries and outline implications for understanding similarities and differences in mothers’ and fathers’ parenting attributions and attitudes. PMID:21927591
Determination of Track Lateral Resistance from Lateral Pull Tests
DOT National Transportation Integrated Search
1986-04-01
Thermal buckling of railroad tracks in the lateral plane is an important problem in the design and maintenance of continuous welded rail (CWR) track. The severity of the problem is manifested through the number of derailments which are attributable t...
Object tracking with stereo vision
NASA Technical Reports Server (NTRS)
Huber, Eric
1994-01-01
A real-time active stereo vision system incorporating gaze control and task directed vision is described. Emphasis is placed on object tracking and object size and shape determination. Techniques include motion-centroid tracking, depth tracking, and contour tracking.
ERIC Educational Resources Information Center
Hennessy, Michael; Bleakley, Amy; Piotrowski, Jessica Taylor; Mallya, Giridhar; Jordan, Amy
2015-01-01
Objective: To examine how parents' beliefs about beverage attributes and exposure to sugar-sweetened beverage (SSB) advertising are associated with parents' and their children's SSB consumption. Design: Cross-sectional representative telephone survey of Philadelphia parents in households with children between the ages of 3 and 16 years.…
Adaptive object tracking via both positive and negative models matching
NASA Astrophysics Data System (ADS)
Li, Shaomei; Gao, Chao; Wang, Yawen
2015-03-01
To improve tracking drift which often occurs in adaptive tracking, an algorithm based on the fusion of tracking and detection is proposed in this paper. Firstly, object tracking is posed as abinary classification problem and is modeled by partial least squares (PLS) analysis. Secondly, tracking object frame by frame via particle filtering. Thirdly, validating the tracking reliability based on both positive and negative models matching. Finally, relocating the object based on SIFT features matching and voting when drift occurs. Object appearance model is updated at the same time. The algorithm can not only sense tracking drift but also relocate the object whenever needed. Experimental results demonstrate that this algorithm outperforms state-of-the-art algorithms on many challenging sequences.
How Many Objects are You Worth? Quantification of the Self-Motion Load on Multiple Object Tracking
Thomas, Laura E.; Seiffert, Adriane E.
2011-01-01
Perhaps walking and chewing gum is effortless, but walking and tracking moving objects is not. Multiple object tracking is impaired by walking from one location to another, suggesting that updating location of the self puts demands on object tracking processes. Here, we quantified the cost of self-motion in terms of the tracking load. Participants in a virtual environment tracked a variable number of targets (1–5) among distractors while either staying in one place or moving along a path that was similar to the objects’ motion. At the end of each trial, participants decided whether a probed dot was a target or distractor. As in our previous work, self-motion significantly impaired performance in tracking multiple targets. Quantifying tracking capacity for each individual under move versus stay conditions further revealed that self-motion during tracking produced a cost to capacity of about 0.8 (±0.2) objects. Tracking your own motion is worth about one object, suggesting that updating the location of the self is similar, but perhaps slightly easier, than updating locations of objects. PMID:21991259
Gregory, William D.; Capots, Larry H.; George, James P.; Janik, Richard
1981-01-01
The type of conductor, its property, and if a metal, its type and cross-sectional area can be obtained from measurements made at different frequencies for the amount of unbalance created in a previously balanced stable coil detection system. The true resistive component is accurately measured and thus reflects only the voltage loss attributable to eddy currents caused by introduction of the test sample to the coil system. This voltage divided by corresponding applied frequency gives a curve which peaks at a frequency dependent upon type of conductor. For a metal this peak frequency is proportional to the samples resistivity divided by its cross-sectional area.
Anderson, Rachel I.; Bush, Peter C.; Spear, Linda P.
2013-01-01
Cues repeatedly paired with rewards often themselves become imbued with enhanced motivational value, or incentive salience. During Pavlovian conditioned approach procedures, a cue repeatedly preceding reward delivery often elicits conditioned responses at either the reward delivery location (“goal-tracking”) or the cue itself (“sign-tracking”). Sign-tracking behavior is thought to reflect the individual differences in attribution of incentive salience to reward-paired cues that may contribute to addiction vulnerability. Adolescent rats typically demonstrate less sign-tracking behavior than adult rats, a surprising finding given that adolescence is hypothesized to be a time of heightened addiction vulnerability. Given evidence that adult sign-tracking behavior can be influenced by environmental conditions, the present study compared the effects of isolate housing and food deprivation on expression of sign-tacking and goal-tracking behavior in adolescent and adult male rats across eight days of a Pavlovian conditioned approach procedure. Pair-housed adults exhibited more sign-tracking behavior than pair-housed adolescents; however, this age difference was not apparent in isolate-housed subjects. Adolescents often appeared more sensitive than adults to both food restriction- and isolate housing-induced changes in behavior, with food restriction promoting an increase in sign-tracking among isolate-housed adolescents and an increase in goal-tracking among pair-housed adolescents. For adults, food restriction resulted in a modest increase in overall expression of both sign-and goal-tracking behavior. To the extent that sign-tracking behavior reflects attribution of incentive salience to reward-paired cues, results from the present study provide evidence that reactivity to rewards during adolescence is strongly related to the nature of the surrounding environment. PMID:24050888
Cohen, Andrew R; Bjornsson, Christopher S; Temple, Sally; Banker, Gary; Roysam, Badrinath
2009-08-01
An algorithmic information-theoretic method is presented for object-level summarization of meaningful changes in image sequences. Object extraction and tracking data are represented as an attributed tracking graph (ATG). Time courses of object states are compared using an adaptive information distance measure, aided by a closed-form multidimensional quantization. The notion of meaningful summarization is captured by using the gap statistic to estimate the randomness deficiency from algorithmic statistics. The summary is the clustering result and feature subset that maximize the gap statistic. This approach was validated on four bioimaging applications: 1) It was applied to a synthetic data set containing two populations of cells differing in the rate of growth, for which it correctly identified the two populations and the single feature out of 23 that separated them; 2) it was applied to 59 movies of three types of neuroprosthetic devices being inserted in the brain tissue at three speeds each, for which it correctly identified insertion speed as the primary factor affecting tissue strain; 3) when applied to movies of cultured neural progenitor cells, it correctly distinguished neurons from progenitors without requiring the use of a fixative stain; and 4) when analyzing intracellular molecular transport in cultured neurons undergoing axon specification, it automatically confirmed the role of kinesins in axon specification.
Leadership, governance and partnerships are essential One Health competencies.
Stephen, Craig; Stemshorn, Barry
2016-12-01
One Health is held as an approach to solve health problems in this era of complexity and globalization, but inadequate attention has been paid to the competencies required to build successful teams and programs. Most of the discussion on developing One Health teams focuses on creating cross-disciplinary awareness and technical skills. There is, however, evidence that collaborative, multi-disciplinary teams need skills, processes and institutions that enable policy and operations to be co-managed and co-delivered across jurisdictions. We propose that competencies in leadership and human resources; governance and infrastructure; and partnership and stakeholder engagement are essential, but often overlooked One Health attributes. Competencies in these staple attributes of leadership and management need to be more prominent in training and One Health capacity development. Although One Health has been in existence for over a decade, there has been no systematic evaluation of the essential attributes of successful and sustainable One Health programs. As such, much of this paper borrows from experience in other sectors dealing with complex, cross and inter-sectoral problems. Our objective is to advocate for increased investment in One Health leadership, governance and partnership skills to balance the focus on creating cross-disciplinary awareness and technical proficiency in order to maintain One Health as a viable approach to health issues at the human-animal-environment interface.
Consumer perception of balsamic vinegar: A cross-cultural study between Korea and Italy.
Torri, Luisa; Jeon, Seon-Young; Piochi, Maria; Morini, Gabriella; Kim, Kwang-Ok
2017-01-01
Understanding cross-cultural differences in food perception is a key issue of food research in order to understand consumer behaviour in different countries. The objective of this study was to explore potential cultural differences of balsamic vinegar perception between Korean and Italian consumers using the sorted napping method. Nine balsamic vinegars different in terms of ingredients, aging time, and origin were evaluated by Korean (n=50) and Italian (n=49) consumers using sorted napping. Familiarity and food matching were also examined. Descriptive analysis was performed to verify the attitude of the consumers in product description. The results obtained from two groups of consumers in Korea and Italy revealed a higher description attitude of the Italians (higher number of total elicited attributes, of attributes in common with the trained panel, of attributes shared with the vocabulary reported in literature, of significant specific positive product-attribute associations). Italian subjects generated various descriptors associated with the European gastronomic culture (aromatic herbs, fortified wine, dried figs, Indian fig, Parmigiano-Reggiano cheese), whereas Korean consumers used more terms related to the Asian food culture (red ginseng, Chinese medicine, Japanese apricot, teriyaki sauce, persimmon vinegar, balloon flower roots). Moreover, cultural differences of food matching were also observed: the Italians would pair the balsamic vinegars mainly with vegetables, fruits and cheese, while Koreans would combine the balsamic vinegars preferably with bread, vegetables and meat. In conclusion, familiarity resulted the main factors for cross-cultural differentiation. Copyright © 2016. Published by Elsevier Ltd.
High-precision spatial localization of mouse vocalizations during social interaction.
Heckman, Jesse J; Proville, Rémi; Heckman, Gert J; Azarfar, Alireza; Celikel, Tansu; Englitz, Bernhard
2017-06-07
Mice display a wide repertoire of vocalizations that varies with age, sex, and context. Especially during courtship, mice emit ultrasonic vocalizations (USVs) of high complexity, whose detailed structure is poorly understood. As animals of both sexes vocalize, the study of social vocalizations requires attributing single USVs to individuals. The state-of-the-art in sound localization for USVs allows spatial localization at centimeter resolution, however, animals interact at closer ranges, involving tactile, snout-snout exploration. Hence, improved algorithms are required to reliably assign USVs. We develop multiple solutions to USV localization, and derive an analytical solution for arbitrary vertical microphone positions. The algorithms are compared on wideband acoustic noise and single mouse vocalizations, and applied to social interactions with optically tracked mouse positions. A novel, (frequency) envelope weighted generalised cross-correlation outperforms classical cross-correlation techniques. It achieves a median error of ~1.4 mm for noise and ~4-8.5 mm for vocalizations. Using this algorithms in combination with a level criterion, we can improve the assignment for interacting mice. We report significant differences in mean USV properties between CBA mice of different sexes during social interaction. Hence, the improved USV attribution to individuals lays the basis for a deeper understanding of social vocalizations, in particular sequences of USVs.
Tracking planets and moons: mechanisms of object tracking revealed with a new paradigm.
Tombu, Michael; Seiffert, Adriane E
2011-04-01
People can attend to and track multiple moving objects over time. Cognitive theories of this ability emphasize location information and differ on the importance of motion information. Results from several experiments have shown that increasing object speed impairs performance, although speed was confounded with other properties such as proximity of objects to one another. Here, we introduce a new paradigm to study multiple object tracking in which object speed and object proximity were manipulated independently. Like the motion of a planet and moon, each target-distractor pair rotated about both a common local point as well as the center of the screen. Tracking performance was strongly affected by object speed even when proximity was controlled. Additional results suggest that two different mechanisms are used in object tracking--one sensitive to speed and proximity and the other sensitive to the number of distractors. These observations support models of object tracking that include information about object motion and reject models that use location alone.
Multiple Hypothesis Tracking (MHT) for Space Surveillance: Results and Simulation Studies
NASA Astrophysics Data System (ADS)
Singh, N.; Poore, A.; Sheaff, C.; Aristoff, J.; Jah, M.
2013-09-01
With the anticipated installation of more accurate sensors and the increased probability of future collisions between space objects, the potential number of observable space objects is likely to increase by an order of magnitude within the next decade, thereby placing an ever-increasing burden on current operational systems. Moreover, the need to track closely-spaced objects due, for example, to breakups as illustrated by the recent Chinese ASAT test or the Iridium-Kosmos collision, requires new, robust, and autonomous methods for space surveillance to enable the development and maintenance of the present and future space catalog and to support the overall space surveillance mission. The problem of correctly associating a stream of uncorrelated tracks (UCTs) and uncorrelated optical observations (UCOs) into common objects is critical to mitigating the number of UCTs and is a prerequisite to subsequent space catalog maintenance. Presently, such association operations are mainly performed using non-statistical simple fixed-gate association logic. In this paper, we report on the salient features and the performance of a newly-developed statistically-robust system-level multiple hypothesis tracking (MHT) system for advanced space surveillance. The multiple-frame assignment (MFA) formulation of MHT, together with supporting astrodynamics algorithms, provides a new joint capability for space catalog maintenance, UCT/UCO resolution, and initial orbit determination. The MFA-MHT framework incorporates multiple hypotheses for report to system track data association and uses a multi-arc construction to accommodate recently developed algorithms for multiple hypothesis filtering (e.g., AEGIS, CAR-MHF, UMAP, and MMAE). This MHT framework allows us to evaluate the benefits of many different algorithms ranging from single- and multiple-frame data association to filtering and uncertainty quantification. In this paper, it will be shown that the MHT system can provide superior tracking performance compared to existing methods at a lower computational cost, especially for closely-spaced objects, in realistic multi-sensor multi-object tracking scenarios over multiple regimes of space. Specifically, we demonstrate that the prototype MHT system can accurately and efficiently process tens of thousands of UCTs and angles-only UCOs emanating from thousands of objects in LEO, GEO, MEO and HELO, many of which are closely-spaced, in real-time on a single laptop computer, thereby making it well-suited for large-scale breakup and tracking scenarios. This is possible in part because complexity reduction techniques are used to control the runtime of MHT without sacrificing accuracy. We assess the performance of MHT in relation to other tracking methods in multi-target, multi-sensor scenarios ranging from easy to difficult (i.e., widely-spaced objects to closely-spaced objects), using realistic physics and probabilities of detection less than one. In LEO, it is shown that the MHT system is able to address the challenges of processing breakups by analyzing multiple frames of data simultaneously in order to improve association decisions, reduce cross-tagging, and reduce unassociated UCTs. As a result, the multi-frame MHT system can establish orbits up to ten times faster than single-frame methods. Finally, it is shown that in GEO, MEO and HELO, the MHT system is able to address the challenges of processing angles-only optical observations by providing a unified multi-frame framework.
Upside-down: Perceived space affects object-based attention.
Papenmeier, Frank; Meyerhoff, Hauke S; Brockhoff, Alisa; Jahn, Georg; Huff, Markus
2017-07-01
Object-based attention influences the subjective metrics of surrounding space. However, does perceived space influence object-based attention, as well? We used an attentive tracking task that required sustained object-based attention while objects moved within a tracking space. We manipulated perceived space through the availability of depth cues and varied the orientation of the tracking space. When rich depth cues were available (appearance of a voluminous tracking space), the upside-down orientation of the tracking space (objects appeared to move high on a ceiling) caused a pronounced impairment of tracking performance compared with an upright orientation of the tracking space (objects appeared to move on a floor plane). In contrast, this was not the case when reduced depth cues were available (appearance of a flat tracking space). With a preregistered second experiment, we showed that those effects were driven by scene-based depth cues and not object-based depth cues. We conclude that perceived space affects object-based attention and that object-based attention and perceived space are closely interlinked. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Hu, Weiming; Li, Xi; Luo, Wenhan; Zhang, Xiaoqin; Maybank, Stephen; Zhang, Zhongfei
2012-12-01
Object appearance modeling is crucial for tracking objects, especially in videos captured by nonstationary cameras and for reasoning about occlusions between multiple moving objects. Based on the log-euclidean Riemannian metric on symmetric positive definite matrices, we propose an incremental log-euclidean Riemannian subspace learning algorithm in which covariance matrices of image features are mapped into a vector space with the log-euclidean Riemannian metric. Based on the subspace learning algorithm, we develop a log-euclidean block-division appearance model which captures both the global and local spatial layout information about object appearances. Single object tracking and multi-object tracking with occlusion reasoning are then achieved by particle filtering-based Bayesian state inference. During tracking, incremental updating of the log-euclidean block-division appearance model captures changes in object appearance. For multi-object tracking, the appearance models of the objects can be updated even in the presence of occlusions. Experimental results demonstrate that the proposed tracking algorithm obtains more accurate results than six state-of-the-art tracking algorithms.
Multi-Object Tracking with Correlation Filter for Autonomous Vehicle.
Zhao, Dawei; Fu, Hao; Xiao, Liang; Wu, Tao; Dai, Bin
2018-06-22
Multi-object tracking is a crucial problem for autonomous vehicle. Most state-of-the-art approaches adopt the tracking-by-detection strategy, which is a two-step procedure consisting of the detection module and the tracking module. In this paper, we improve both steps. We improve the detection module by incorporating the temporal information, which is beneficial for detecting small objects. For the tracking module, we propose a novel compressed deep Convolutional Neural Network (CNN) feature based Correlation Filter tracker. By carefully integrating these two modules, the proposed multi-object tracking approach has the ability of re-identification (ReID) once the tracked object gets lost. Extensive experiments were performed on the KITTI and MOT2015 tracking benchmarks. Results indicate that our approach outperforms most state-of-the-art tracking approaches.
Fluctuations in Conjunction Miss Distance Projections as Time Approaches Time of Closest Approach
NASA Technical Reports Server (NTRS)
Christian, John A., III
2005-01-01
A responsibility of the Trajectory Operations Officer is to ensure that the International Space Station (ISS) avoids colliding with debris. United States Space Command (USSPACECOM) tracks and catalogs a portion of the debris in Earth orbit, but only objects with a perigee less than 600 km and a radar cross section (RCS) greater than 10 cm-objects that, in fact, represent only a small fraction of the objects in Earth orbit. To accommodate for this, the ISS uses shielding to protect against collisions with smaller objects. This study provides a better understanding of how quickly, and to what degree, USSPACECOM projections tend to converge to the final, true miss distance. The information included is formulated to better predict the behavior of miss distance data during real-time operations. It was determined that the driving components, in order of impact on miss distance fluctuations, are energy dissipation rate (EDR), RCS, and inclination. Data used in this analysis, calculations made, and conclusions drawn are stored in Microsoft Excel log sheets. A separate log sheet, created for each conjunction, contains information such as predicted miss distances, apogee and perigee of debris orbit, EDR, RCS, inclination, tracks and observations, statistical data, and other evaluation/orbital parameters.
The Status of Women in US Academic Pharmacy
Plaza, Cecilia M.; Taylor, Danielle A.; Meyer, Susan M.
2014-01-01
Objective. To describe the status of women in pharmacy education with particular focus on a 10-year update of a previous study. Methods. Information was obtained from national databases, published reports, scholarly articles, and association websites. Comparisons were made between men and women regarding degree completion, rank, tenure status, leadership positions, research awards, salaries, and career advancement. Results. There have been modest gains in the number of women serving as department chairs and deans. Salary disparities were found between men and women at several ranks within pharmacy practice. Men were more apt to be tenured or in tenure-track positions and received 89.4% of the national achievement awards tracked since 1981. Conclusion. The problem cannot be simply attributed to the pipeline of those entering academia. Barriers to advancement differ between men and women. We recommend that individuals, institutions, and associations implement strategies to decrease barriers and reduce bias against women. PMID:25657365
NASA Technical Reports Server (NTRS)
Lewis, Steven J.; Palacios, David M.
2013-01-01
This software can track multiple moving objects within a video stream simultaneously, use visual features to aid in the tracking, and initiate tracks based on object detection in a subregion. A simple programmatic interface allows plugging into larger image chain modeling suites. It extracts unique visual features for aid in tracking and later analysis, and includes sub-functionality for extracting visual features about an object identified within an image frame. Tracker Toolkit utilizes a feature extraction algorithm to tag each object with metadata features about its size, shape, color, and movement. Its functionality is independent of the scale of objects within a scene. The only assumption made on the tracked objects is that they move. There are no constraints on size within the scene, shape, or type of movement. The Tracker Toolkit is also capable of following an arbitrary number of objects in the same scene, identifying and propagating the track of each object from frame to frame. Target objects may be specified for tracking beforehand, or may be dynamically discovered within a tripwire region. Initialization of the Tracker Toolkit algorithm includes two steps: Initializing the data structures for tracked target objects, including targets preselected for tracking; and initializing the tripwire region. If no tripwire region is desired, this step is skipped. The tripwire region is an area within the frames that is always checked for new objects, and all new objects discovered within the region will be tracked until lost (by leaving the frame, stopping, or blending in to the background).
Network exploitation using WAMI tracks
NASA Astrophysics Data System (ADS)
Rimey, Ray; Record, Jim; Keefe, Dan; Kennedy, Levi; Cramer, Chris
2011-06-01
Creating and exploiting network models from wide area motion imagery (WAMI) is an important task for intelligence analysis. Tracks of entities observed moving in the WAMI sensor data are extracted, then large numbers of tracks are studied over long time intervals to determine specific locations that are visited (e.g., buildings in an urban environment), what locations are related to other locations, and the function of each location. This paper describes several parts of the network detection/exploitation problem, and summarizes a solution technique for each: (a) Detecting nodes; (b) Detecting links between known nodes; (c) Node attributes to characterize a node; (d) Link attributes to characterize each link; (e) Link structure inferred from node attributes and vice versa; and (f) Decomposing a detected network into smaller networks. Experimental results are presented for each solution technique, and those are used to discuss issues for each problem part and its solution technique.
Neighborhood Environments and Objectively Measured Physical Activity in 11 Countries
Cerin, Ester; Cain, Kelli L; Conway, Terry L; Dyck, Delfien Van; Hinckson, Erica; Schipperijn, Jasper; Bourdeaudhuij, Ilse De; Owen, Neville; Davey, Rachel C; Hino, Adriano Akira Ferreira; Mitáš, Josef; Orzanco-Garralda, Rosario; Salvo, Deborah; Sarmiento, Olga L; Christiansen, Lars B; Macfarlane, Duncan J; Schofield, Grant; Sallis, James F
2014-01-01
Purpose Environmental changes are potentially effective population-level physical activity (PA) promotion strategies. However, robust multi-site evidence to guide international action for developing activity-supportive environments is lacking. We estimated pooled associations of perceived environmental attributes with objectively-measured PA outcomes; between-site differences in such associations; and, the extent to which perceived environmental attributes explain between-site differences in PA. Methods This was a cross-sectional study conducted in 16 cities located in Belgium, Brazil, Colombia, Czech Republic, Denmark, China, Mexico, New Zealand, Spain, United Kingdom, and USA. Participants were 6,968 adults residing in administrative units stratified by socio-economic status and transport-related walkability. Predictors were 10 perceived neighborhood environmental attributes. Outcome measures were accelerometry-assessed weekly minutes of moderate-to-vigorous PA (MVPA) and meeting the PA guidelines for cancer/weight gain prevention (420 min/week of MVPA). Results Most perceived neighborhood attributes were positively associated with the PA outcomes in the pooled, site-adjusted, single-predictor models. Associations were generalizable across geographical locations. Aesthetics and land use mix – access were significant predictors of both PA outcomes in the fully-adjusted models. Environmental attributes accounted for within-site variability in MVPA corresponding to a 3 min/d or 21 min/week standard deviation. Large between-site differences in PA outcomes were observed: 15.9% to 16.8% of these differences were explained by perceived environmental attributes. All neighborhood attributes were associated with between-site differences in the total effects of the perceived environment on PA outcomes. Conclusions Residents’ perceptions of neighborhood attributes that facilitate walking were positively associated with objectively-measured MVPA and meeting the guidelines for cancer/weight gain prevention at the within- and between-site levels. Associations were similar across study sites, lending support for international recommendations for designing PA-friendly built environments. PMID:24781892
Wakefield, Melanie; Coomber, Kerri; Zacher, Meghan; Durkin, Sarah; Brennan, Emily; Scollo, Michelle
2015-04-01
We assessed whether the Australian plain packs with larger graphic health warnings (GHWs) achieved three specific objectives of reducing the appeal of tobacco, increasing health warning effectiveness and reducing the ability of packaging to mislead about smoking harms. We compared responses from continuous cross-sectional telephone surveys of n=2176 cigarette smokers during pre-plain packaging (April-September 2012, pre-PP) with n=759 surveyed in the transition period (October-November 2012) and n=4240 during the first year of implementation (December 2012-November 2013, PP year 1), using multivariate logistic regression analyses. From pre-PP to PP year 1, more smokers disliked their pack (p<0.001), perceived lower pack appeal (p<0.001), lower cigarette quality (p<0.001), lower satisfaction (p<0.001) and lower value (p<0.001) and disagreed brands differed in prestige (p=0.003). There was no change in perceived differences in taste of different brands. More smokers noticed GHWs (p<0.001), attributed much motivation to quit to GHWs (p<0.001), avoided specific GHWs when purchasing (p<0.001), and covered packs (p<0.001), with no change in perceived exaggeration of harms. PP year 1 saw an increased proportion believing that brands do not differ in harmfulness (p=0.004), but no change in the belief that variants do not differ in strength or the perceived harmfulness of cigarettes compared with a year ago. Interactions signified greater change for four outcomes assessing aspects of appeal among young adults and two appeal outcomes among mid-aged adults. The specific objectives of plain packaging were achieved and generally sustained among adult smokers up to 12 months after implementation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Human-like object tracking and gaze estimation with PKD android
Wijayasinghe, Indika B.; Miller, Haylie L.; Das, Sumit K; Bugnariu, Nicoleta L.; Popa, Dan O.
2018-01-01
As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold : to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans. PMID:29416193
Human-like object tracking and gaze estimation with PKD android
NASA Astrophysics Data System (ADS)
Wijayasinghe, Indika B.; Miller, Haylie L.; Das, Sumit K.; Bugnariu, Nicoleta L.; Popa, Dan O.
2016-05-01
As the use of robots increases for tasks that require human-robot interactions, it is vital that robots exhibit and understand human-like cues for effective communication. In this paper, we describe the implementation of object tracking capability on Philip K. Dick (PKD) android and a gaze tracking algorithm, both of which further robot capabilities with regard to human communication. PKD's ability to track objects with human-like head postures is achieved with visual feedback from a Kinect system and an eye camera. The goal of object tracking with human-like gestures is twofold: to facilitate better human-robot interactions and to enable PKD as a human gaze emulator for future studies. The gaze tracking system employs a mobile eye tracking system (ETG; SensoMotoric Instruments) and a motion capture system (Cortex; Motion Analysis Corp.) for tracking the head orientations. Objects to be tracked are displayed by a virtual reality system, the Computer Assisted Rehabilitation Environment (CAREN; MotekForce Link). The gaze tracking algorithm converts eye tracking data and head orientations to gaze information facilitating two objectives: to evaluate the performance of the object tracking system for PKD and to use the gaze information to predict the intentions of the user, enabling the robot to understand physical cues by humans.
An international program to protect the earth from impact catastrophe - Initial steps
NASA Technical Reports Server (NTRS)
Morrison, David
1992-01-01
Risks posed by impacting objects of various sizes are analyzed using the Spaceguard Survey, the 1992 NASA report of International Near-Earth-Object (NEO) Detection workshop. The state-of-the-art technology makes it possible to discover and track nearly all earth-crossing asteroids and short-period comets large enough to threaten global catastrophe. To deal with this hazard a long-term telescopic search is required that reaches stellar magnitude 22 in order to achieve a nearly complete census of objects 1 km or larger. A program can be performed on the basis of an international network of six telescopes of 2-3 m aperture equipped with modern CCD detectors and automatic signal processing capability.
Predictors of Academic Success between On Track and Off Track Students in a Mexican University
ERIC Educational Resources Information Center
Hinojos, Jesus Francisco
2013-01-01
The main purpose of this study was to assess how predictors of quality of academic effort relate to academic success and student persistence of on-track and off-track students in a higher education institution in Northern Mexico; to investigate the relationship of pre-entry attributes, family background and academic success as expressed by GPA…
A data set for evaluating the performance of multi-class multi-object video tracking
NASA Astrophysics Data System (ADS)
Chakraborty, Avishek; Stamatescu, Victor; Wong, Sebastien C.; Wigley, Grant; Kearney, David
2017-05-01
One of the challenges in evaluating multi-object video detection, tracking and classification systems is having publically available data sets with which to compare different systems. However, the measures of performance for tracking and classification are different. Data sets that are suitable for evaluating tracking systems may not be appropriate for classification. Tracking video data sets typically only have ground truth track IDs, while classification video data sets only have ground truth class-label IDs. The former identifies the same object over multiple frames, while the latter identifies the type of object in individual frames. This paper describes an advancement of the ground truth meta-data for the DARPA Neovision2 Tower data set to allow both the evaluation of tracking and classification. The ground truth data sets presented in this paper contain unique object IDs across 5 different classes of object (Car, Bus, Truck, Person, Cyclist) for 24 videos of 871 image frames each. In addition to the object IDs and class labels, the ground truth data also contains the original bounding box coordinates together with new bounding boxes in instances where un-annotated objects were present. The unique IDs are maintained during occlusions between multiple objects or when objects re-enter the field of view. This will provide: a solid foundation for evaluating the performance of multi-object tracking of different types of objects, a straightforward comparison of tracking system performance using the standard Multi Object Tracking (MOT) framework, and classification performance using the Neovision2 metrics. These data have been hosted publically.
Real-time object detection, tracking and occlusion reasoning
DOE Office of Scientific and Technical Information (OSTI.GOV)
Divakaran, Ajay; Yu, Qian; Tamrakar, Amir
A system for object detection and tracking includes technologies to, among other things, detect and track moving objects, such as pedestrians and/or vehicles, in a real-world environment, handle static and dynamic occlusions, and continue tracking moving objects across the fields of view of multiple different cameras.
Self-Motion Impairs Multiple-Object Tracking
ERIC Educational Resources Information Center
Thomas, Laura E.; Seiffert, Adriane E.
2010-01-01
Investigations of multiple-object tracking aim to further our understanding of how people perform common activities such as driving in traffic. However, tracking tasks in the laboratory have overlooked a crucial component of much real-world object tracking: self-motion. We investigated the hypothesis that keeping track of one's own movement…
Ryan, Mandy; Krucien, Nicolas; Hermens, Frouke
2018-04-01
Although choice experiments (CEs) are widely applied in economics to study choice behaviour, understanding of how individuals process attribute information remains limited. We show how eye-tracking methods can provide insight into how decisions are made. Participants completed a CE, while their eye movements were recorded. Results show that although the information presented guided participants' decisions, there were also several processing biases at work. Evidence was found of (a) top-to-bottom, (b) left-to-right, and (c) first-to-last order biases. Experimental factors-whether attributes are defined as "best" or "worst," choice task complexity, and attribute ordering-also influence information processing. How individuals visually process attribute information was shown to be related to their choices. Implications for the design and analysis of CEs and future research are discussed. Copyright © 2017 John Wiley & Sons, Ltd.
Visual object recognition and tracking
NASA Technical Reports Server (NTRS)
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.
Structure preserving clustering-object tracking via subgroup motion pattern segmentation
NASA Astrophysics Data System (ADS)
Fan, Zheyi; Zhu, Yixuan; Jiang, Jiao; Weng, Shuqin; Liu, Zhiwen
2018-01-01
Tracking clustering objects with similar appearances simultaneously in collective scenes is a challenging task in the field of collective motion analysis. Recent work on clustering-object tracking often suffers from poor tracking accuracy and terrible real-time performance due to the neglect or the misjudgment of the motion differences among objects. To address this problem, we propose a subgroup motion pattern segmentation framework based on a multilayer clustering structure and establish spatial constraints only among objects in the same subgroup, which entails having consistent motion direction and close spatial position. In addition, the subgroup segmentation results are updated dynamically because crowd motion patterns are changeable and affected by objects' destinations and scene structures. The spatial structure information combined with the appearance similarity information is used in the structure preserving object tracking framework to track objects. Extensive experiments conducted on several datasets containing multiple real-world crowd scenes validate the accuracy and the robustness of the presented algorithm for tracking objects in collective scenes.
Population trends influence species ability to track climate change
Joel Ralston; William V. DeLuca; Richard E. Feldman; David I. King
2016-01-01
Shifts of distributions have been attributed to species tracking their fundamental climate niches through space. However, several studies have now demonstrated that niche tracking is imperfect, that species' climate niches may vary with population trends, and that geographic distributions may lag behind rapid climate change. These reports of imperfect niche...
Ahrens, Allison M; Ferguson, Lindsay M; Robinson, Terry E; Aldridge, J Wayne
2018-01-01
Some rats are especially prone to attribute incentive salience to a cue (conditioned stimulus, CS) paired with food reward (sign-trackers, STs), but the extent they do so varies as a function of the form of the CS. Other rats respond primarily to the predictive value of a cue (goal-trackers, GTs), regardless of its form. Sign-tracking is associated with greater cue-induced activation of mesolimbic structures than goal-tracking; however, it is unclear how the form of the CS itself influences activity in neural systems involved in incentive salience attribution. Thus, our goal was to determine how different cue modalities affect neural activity in the ventral pallidum (VP), which is known to encode incentive salience attribution, as rats performed a two-CS Pavlovian conditioned approach task in which both a lever-CS and a tone-CS predicted identical food reward. The lever-CS elicited sign-tracking in some rats (STs) and goal-tracking in others (GTs), whereas the tone-CS elicited only goal-tracking in all rats. The lever-CS elicited robust changes in neural activity (sustained tonic increases or decreases in firing) throughout the VP in STs, relative to GTs. These changes were not seen when STs were exposed to the tone-CS, and in GTs there were no differences in firing between the lever-CS and tone-CS. We conclude that neural activity throughout the VP encodes incentive signals and is especially responsive when a cue is of a form that promotes the attribution of incentive salience to it, especially in predisposed individuals.
NPP ATMS Prelaunch Performance Assessment and Sensor Data Record Validation
2011-04-29
TMS to sense scattering of cold cosmic background radiance from the tops of preci pitating clouds allows the retrieval of preCipitation intensities...operational and research missions over the last 40 years. The Cross-track Infrared and Microwave Sounding Suite (CrIMSS), consisting of the Cross-track...Infrared Sounder (CrrS) and the flIst space-based, Nyquist-sampled cross-track microwave sounder, the Advanced Technology Microwave Sounder (ATMS), will
NASA Technical Reports Server (NTRS)
Porter, D. W.; Lefler, R. M.
1979-01-01
A generalized hypothesis testing approach is applied to the problem of tracking several objects where several different associations of data with objects are possible. Such problems occur, for instance, when attempting to distinctly track several aircraft maneuvering near each other or when tracking ships at sea. Conceptually, the problem is solved by first, associating data with objects in a statistically reasonable fashion and then, tracking with a bank of Kalman filters. The objects are assumed to have motion characterized by a fixed but unknown deterministic portion plus a random process portion modeled by a shaping filter. For example, the object might be assumed to have a mean straight line path about which it maneuvers in a random manner. Several hypothesized associations of data with objects are possible because of ambiguity as to which object the data comes from, false alarm/detection errors, and possible uncertainty in the number of objects being tracked. The statistical likelihood function is computed for each possible hypothesized association of data with objects. Then the generalized likelihood is computed by maximizing the likelihood over parameters that define the deterministic motion of the object.
Tracking of multiple targets using online learning for reference model adaptation.
Pernkopf, Franz
2008-12-01
Recently, much work has been done in multiple object tracking on the one hand and on reference model adaptation for a single-object tracker on the other side. In this paper, we do both tracking of multiple objects (faces of people) in a meeting scenario and online learning to incrementally update the models of the tracked objects to account for appearance changes during tracking. Additionally, we automatically initialize and terminate tracking of individual objects based on low-level features, i.e., face color, face size, and object movement. Many methods unlike our approach assume that the target region has been initialized by hand in the first frame. For tracking, a particle filter is incorporated to propagate sample distributions over time. We discuss the close relationship between our implemented tracker based on particle filters and genetic algorithms. Numerous experiments on meeting data demonstrate the capabilities of our tracking approach. Additionally, we provide an empirical verification of the reference model learning during tracking of indoor and outdoor scenes which supports a more robust tracking. Therefore, we report the average of the standard deviation of the trajectories over numerous tracking runs depending on the learning rate.
Tracking planets and moons: mechanisms of object tracking revealed with a new paradigm
Tombu, Michael
2014-01-01
People can attend to and track multiple moving objects over time. Cognitive theories of this ability emphasize location information and differ on the importance of motion information. Results from several experiments have shown that increasing object speed impairs performance, although speed was confounded with other properties such as proximity of objects to one another. Here, we introduce a new paradigm to study multiple object tracking in which object speed and object proximity were manipulated independently. Like the motion of a planet and moon, each target–distractor pair rotated about both a common local point as well as the center of the screen. Tracking performance was strongly affected by object speed even when proximity was controlled. Additional results suggest that two different mechanisms are used in object tracking—one sensitive to speed and proximity and the other sensitive to the number of distractors. These observations support models of object tracking that include information about object motion and reject models that use location alone. PMID:21264704
Computer-aided target tracking in motion analysis studies
NASA Astrophysics Data System (ADS)
Burdick, Dominic C.; Marcuse, M. L.; Mislan, J. D.
1990-08-01
Motion analysis studies require the precise tracking of reference objects in sequential scenes. In a typical situation, events of interest are captured at high frame rates using special cameras, and selected objects or targets are tracked on a frame by frame basis to provide necessary data for motion reconstruction. Tracking is usually done using manual methods which are slow and prone to error. A computer based image analysis system has been developed that performs tracking automatically. The objective of this work was to eliminate the bottleneck due to manual methods in high volume tracking applications such as the analysis of crash test films for the automotive industry. The system has proven to be successful in tracking standard fiducial targets and other objects in crash test scenes. Over 95 percent of target positions which could be located using manual methods can be tracked by the system, with a significant improvement in throughput over manual methods. Future work will focus on the tracking of clusters of targets and on tracking deformable objects such as airbags.
Multiple-object tracking while driving: the multiple-vehicle tracking task.
Lochner, Martin J; Trick, Lana M
2014-11-01
Many contend that driving an automobile involves multiple-object tracking. At this point, no one has tested this idea, and it is unclear how multiple-object tracking would coordinate with the other activities involved in driving. To address some of the initial and most basic questions about multiple-object tracking while driving, we modified the tracking task for use in a driving simulator, creating the multiple-vehicle tracking task. In Experiment 1, we employed a dual-task methodology to determine whether there was interference between tracking and driving. Findings suggest that although it is possible to track multiple vehicles while driving, driving reduces tracking performance, and tracking compromises headway and lane position maintenance while driving. Modified change-detection paradigms were used to assess whether there were change localization advantages for tracked targets in multiple-vehicle tracking. When changes occurred during a blanking interval, drivers were more accurate (Experiment 2a) and ~250 ms faster (Experiment 2b) at locating the vehicle that changed when it was a target rather than a distractor in tracking. In a more realistic driving task where drivers had to brake in response to the sudden onset of brake lights in one of the lead vehicles, drivers were more accurate at localizing the vehicle that braked if it was a tracking target, although there was no advantage in terms of braking response time. Overall, results suggest that multiple-object tracking is possible while driving and perhaps even advantageous in some situations, but further research is required to determine whether multiple-object tracking is actually used in day-to-day driving.
Isolating the incentive salience of reward-associated stimuli: value, choice, and persistence
Chow, Jonathan J.
2015-01-01
Sign- and goal-tracking are differentially associated with drug abuse-related behavior. Recently, it has been hypothesized that sign- and goal-tracking behavior are mediated by different neurobehavioral valuation systems, including differential incentive salience attribution. Herein, we used different conditioned stimuli to preferentially elicit different response types to study the different incentive valuation characteristics of stimuli associated with sign- and goal-tracking within individuals. The results demonstrate that all stimuli used were equally effective conditioned stimuli; however, only a lever stimulus associated with sign-tracking behavior served as a robust conditioned reinforcer and was preferred over a tone associated with goal-tracking. Moreover, the incentive value attributed to the lever stimulus was capable of promoting suboptimal choice, leading to a significant reduction in reinforcers (food) earned. Furthermore, sign-tracking to a lever was more persistent than goal-tracking to a tone under omission and extinction contingencies. Finally, a conditional discrimination procedure demonstrated that sign-tracking to a lever and goal-tracking to a tone were dependent on learned stimulus–reinforcer relations. Collectively, these results suggest that the different neurobehavioral valuation processes proposed to govern sign- and goal-tracking behavior are independent but parallel processes within individuals. Examining these systems within individuals will provide a better understanding of how one system comes to dominate stimulus–reward learning, thus leading to the differential role these systems play in abuse-related behavior. PMID:25593298
"OZONE SOURCE APPORTIONMENT IN CMAQ' | Science ...
Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental transport of ozone and ozone precursors and delineating anthropogenic and non-anthropogenic contribution to ozone in North America. As in the public release due in September 2013, CMAQ’s Integrated Source Apportionment Method (ISAM) attributes PM EC/OC, sulfate, nitrate, ammonium, ozone and its precursors NOx and VOC, to sectors/regions of users’ interest. Although the peroxide-to-nitric acid productions ratio has been the most common indicator to distinguish NOx-limited ozone production from VOC-limited one, other indicators are implemented in addition to allowing for an ensemble decision based on a total of 9 available indicator ratios. Moreover, an alternative approach of ozone attribution based on the idea of chemical sensitivity in a linearized system that has formed the basis of chemical treatment in forward DDM/backward adjoint tools has been implemented in CMAQ. This method does not require categorization into either ozone regime. In this study, ISAM will simulate the 2010 North America ozone using all of the above gas-phase attribution methods. The results are to be compared with zero-out difference out of those sectors in the host model runs. In addition, ozone contribution wil
Radar signature generation for feature-aided tracking research
NASA Astrophysics Data System (ADS)
Piatt, Teri L.; Sherwood, John U.; Musick, Stanton H.
2005-05-01
Accurately associating sensor kinematic reports to known tracks, new tracks, or clutter is one of the greatest obstacles to effective track estimation. Feature-aiding is one technology that is emerging to address this problem, and it is expected that adding target features will aid report association by enhancing track accuracy and lengthening track life. The Sensor's Directorate of the Air Force Research Laboratory is sponsoring a challenge problem called Feature-Aided Tracking of Stop-move Objects (FATSO). The long-range goal of this research is to provide a full suite of public data and software to encourage researchers from government, industry, and academia to participate in radar-based feature-aided tracking research. The FATSO program is currently releasing a vehicle database coupled to a radar signature generator. The completed FATSO system will incorporate this database/generator into a Monte Carlo simulation environment for evaluating multiplatform/multitarget tracking scenarios. The currently released data and software contains the following: eight target models, including a tank, ammo hauler, and self-propelled artillery vehicles; and a radar signature generator capable of producing SAR and HRR signatures of all eight modeled targets in almost any configuration or articulation. In addition, the signature generator creates Z-buffer data, label map data, and radar cross-section prediction and allows the user to add noise to an image while varying sensor-target geometry (roll, pitch, yaw, squint). Future capabilities of this signature generator, such as scene models and EO signatures as well as details of the complete FATSO testbed, are outlined.
Identification of hump highway/rail crossings in Kansas
DOT National Transportation Integrated Search
2003-07-01
Hump crossings or high-profile crossings are a highway/rail intersection (HRI) at which the road surface profile across the rail tracks may pose a risk of a low-clearance vehicle becoming stuck on the tracks. They may also pose a threat to heavy vehi...
Effect of inclination direction on recording performance of BPM with inclined anisotropy
NASA Astrophysics Data System (ADS)
Honda, Naoki; Yamakawa, Kiyoshi; Ouchi, Kazuhiro; Komukai, Tatsuya
Effect of inclination direction on the recording performance of bit-patterned media with weakly inclined anisotropy was investigated by simulation. Magnetic dots with a size of 15x7.5x5 nm3 were arranged on a soft magnetic underlayer with an areal density of 2.6 Tdot/in2. Saturation magnetization of each dot was assumed to be 1000 emu/cm3. Media with three different inclination directions with an inclination angle of 30 degrees from the film normal, which were down-track inclined, cross-track inclined and cone-state, were investigated for the recording performance using a shielded planar head field. Although the three media exhibited almost the same remanence curve, obtained recording performance indicated different write shift margins. It was found that the write shift margin in the cross-track direction increased for the media with fixed inclined anisotropy axes, but the medium with the inclination direction in the cross-track direction exhibited larger shift margin than that of the down-track inclined medium when the anisotropy field dispersion was increased to 4%, while increase in the write shift margin in the downtrack direction was similar for down- and cross-track inclined media. The cause of the difference was primarily explained by the composite anisotropy of the elongated dot with the shape anisotropy in the cross-track direction.
NASA Technical Reports Server (NTRS)
Flament, Pierre; Graber, Hans C.; Halpern, D.; Holt, B.
1996-01-01
The objective of this project is to study fronts that develop at the boundary between cold water recently upwelled to the surface through Ekman divergence, and warmer surrounding waters. This specific objective was suggested by studying the small scale structure of upwelling fronts (coastal, island, and equatorial) through shipboard surveys and infrared satellite images. Constraints on the shuttle equator crossing imposed by other land sites precluded a coverage of the area targeted in the initial SIR-C proposal, the California Current. The site was then relocated to the Equatorial Pacific upwelling tongue, that can be satisfactorily imaged for a wide range of longitudes of the equator crossing. Some limited data was nevertheless obtained over coastal upwelling off California in 1989, using the JPL AIRSAR in multifrequency mode, and over island upwelling off Hawaii in 1990, using the radar in along-track interferometric mode.
Learned filters for object detection in multi-object visual tracking
NASA Astrophysics Data System (ADS)
Stamatescu, Victor; Wong, Sebastien; McDonnell, Mark D.; Kearney, David
2016-05-01
We investigate the application of learned convolutional filters in multi-object visual tracking. The filters were learned in both a supervised and unsupervised manner from image data using artificial neural networks. This work follows recent results in the field of machine learning that demonstrate the use learned filters for enhanced object detection and classification. Here we employ a track-before-detect approach to multi-object tracking, where tracking guides the detection process. The object detection provides a probabilistic input image calculated by selecting from features obtained using banks of generative or discriminative learned filters. We present a systematic evaluation of these convolutional filters using a real-world data set that examines their performance as generic object detectors.
The what-where trade-off in multiple-identity tracking.
Cohen, Michael A; Pinto, Yair; Howe, Piers D L; Horowitz, Todd S
2011-07-01
Observers are poor at reporting the identities of objects that they have successfully tracked (Pylyshyn, Visual Cognition, 11, 801-822, 2004; Scholl & Pylyshyn, Cognitive Psychology, 38, 259-290, 1999). Consequently, it has been claimed that objects are tracked in a manner that does not encode their identities (Pylyshyn, 2004). Here, we present evidence that disputes this claim. In a series of experiments, we show that attempting to track the identities of objects can decrease an observer's ability to track the objects' locations. This indicates that the mechanisms that track, respectively, the locations and identities of objects draw upon a common resource. Furthermore, we show that this common resource can be voluntarily distributed between the two mechanisms. This is clear evidence that the location- and identity-tracking mechanisms are not entirely dissociable.
Briken, Peer; Dekker, Arne
2018-01-01
In their foundational work on the social construction of gender, Kessler and McKenna (1978) investigated the relationship between gender attribution and genital attribution. We used digital reproductions of the original stimuli to replicate their findings in the current social context. To further investigate the underlying decision processes we applied eye tracking. The stimuli shown varied in the composition of gender cues: from those more commonly associated with maleness to associated with femaleness. Applying the ethnomethodological approach originally used, participants were asked to decide for each stimulus whether they saw a man or a woman and to indicate subjective confidence with the decision. In line with the original results we found that the genital attribution contributed immensely to the gender attribution. Also, male gender was ascribed more often when the penis was present than was female gender when the vulva was shown. Eye tracking revealed that overall most dwell time as a proxy for important information was dedicated to the head, chest and genital areas of all the stimuli. Total dwell time depended on whether the gender attribution was made in line with the depicted genital, if the genital was a penis. Attributing female gender when a penis was present was associated with longer total dwell time, unlike attributing male gender with a vulva shown. This is indicative of higher cognitive effort and more difficulty ignoring the penis as opposed to the vulva. We interpret this finding in context of the persistent male dominance as well as to the socio-cultural understanding of the vulva as a concealed and therefore seemingly absent organ. In summary, we were able to show that the gender attribution is still closely linked to genital attribution when having a binary forced choice task and that the penis is a special cue in this attribution process. PMID:29494689
Post-Structural Methodology at the Quilting Point: Intercultural Encounters.
Gillett, Grant
Lacan's quilting point connects a network of signifiers with the lived world as a place of voices, memory, and adaptation "seen in" the mirror of language. Crossing cultures can obscure the ways we make sense of the world. Some planes of signification, in aiming to be universal in their knowledge (such as the natural sciences), try to track objects and events independent of our thoughts about them and the ways that signifiers may slide past each other. However, cross-structural comparison and the analysis of cross cultural encounters cannot treat its objects of interest that way. Thus we need a theory and methodology that effectively connects the multilayered discourses of subjectivities from diverse cultures and allows triangulation between them in relation to points of shared experience. At such points we need a critical attitude to our own framework and an openness to the uneasy reflective equilibrium that uncovers assumptions and modes of thinking that will hamper us. Quilting points are such points where different discourses converge on a single event or set of events so as to mark "vertical" connections allowing tentative alignments between ways of meaning so that we can begin to build real cross-cultural understanding.
Horowitz, Todd S.; Kuzmova, Yoana
2011-01-01
The evidence is mixed as to whether the visual system treats objects and holes differently. We used a multiple object tracking task to test the hypothesis that figural objects are easier to track than holes. Observers tracked four of eight items (holes or objects). We used an adaptive algorithm to estimate the speed allowing 75% tracking accuracy. In Experiments 1–5, the distinction between holes and figures was accomplished by pictorial cues, while red-cyan anaglyphs were used to provide the illusion of depth in Experiment 6. We variously used Gaussian pixel noise, photographic scenes, or synthetic textures as backgrounds. Tracking was more difficult when a complex background was visible, as opposed to a blank background. Tracking was easier when disks carried fixed, unique markings. When these factors were controlled for, tracking holes was no more difficult than tracking figures, suggesting that they are equivalent stimuli for tracking purposes. PMID:21334361
Cortical Circuit for Binding Object Identity and Location During Multiple-Object Tracking
Nummenmaa, Lauri; Oksama, Lauri; Glerean, Erico; Hyönä, Jukka
2017-01-01
Abstract Sustained multifocal attention for moving targets requires binding object identities with their locations. The brain mechanisms of identity-location binding during attentive tracking have remained unresolved. In 2 functional magnetic resonance imaging experiments, we measured participants’ hemodynamic activity during attentive tracking of multiple objects with equivalent (multiple-object tracking) versus distinct (multiple identity tracking, MIT) identities. Task load was manipulated parametrically. Both tasks activated large frontoparietal circuits. MIT led to significantly increased activity in frontoparietal and temporal systems subserving object recognition and working memory. These effects were replicated when eye movements were prohibited. MIT was associated with significantly increased functional connectivity between lateral temporal and frontal and parietal regions. We propose that coordinated activity of this network subserves identity-location binding during attentive tracking. PMID:27913430
Huettig, Falk; Altmann, Gerry T M
2011-01-01
Three eye-tracking experiments investigated the influence of stored colour knowledge, perceived surface colour, and conceptual category of visual objects on language-mediated overt attention. Participants heard spoken target words whose concepts are associated with a diagnostic colour (e.g., "spinach"; spinach is typically green) while their eye movements were monitored to (a) objects associated with a diagnostic colour but presented in black and white (e.g., a black-and-white line drawing of a frog), (b) objects associated with a diagnostic colour but presented in an appropriate but atypical colour (e.g., a colour photograph of a yellow frog), and (c) objects not associated with a diagnostic colour but presented in the diagnostic colour of the target concept (e.g., a green blouse; blouses are not typically green). We observed that colour-mediated shifts in overt attention are primarily due to the perceived surface attributes of the visual objects rather than stored knowledge about the typical colour of the object. In addition our data reveal that conceptual category information is the primary determinant of overt attention if both conceptual category and surface colour competitors are copresent in the visual environment.
Traffic monitoring with distributed smart cameras
NASA Astrophysics Data System (ADS)
Sidla, Oliver; Rosner, Marcin; Ulm, Michael; Schwingshackl, Gert
2012-01-01
The observation and monitoring of traffic with smart visions systems for the purpose of improving traffic safety has a big potential. Today the automated analysis of traffic situations is still in its infancy--the patterns of vehicle motion and pedestrian flow in an urban environment are too complex to be fully captured and interpreted by a vision system. 3In this work we present steps towards a visual monitoring system which is designed to detect potentially dangerous traffic situations around a pedestrian crossing at a street intersection. The camera system is specifically designed to detect incidents in which the interaction of pedestrians and vehicles might develop into safety critical encounters. The proposed system has been field-tested at a real pedestrian crossing in the City of Vienna for the duration of one year. It consists of a cluster of 3 smart cameras, each of which is built from a very compact PC hardware system in a weatherproof housing. Two cameras run vehicle detection and tracking software, one camera runs a pedestrian detection and tracking module based on the HOG dectection principle. All 3 cameras use sparse optical flow computation in a low-resolution video stream in order to estimate the motion path and speed of objects. Geometric calibration of the cameras allows us to estimate the real-world co-ordinates of detected objects and to link the cameras together into one common reference system. This work describes the foundation for all the different object detection modalities (pedestrians, vehicles), and explains the system setup, tis design, and evaluation results which we have achieved so far.
Multiple Learning Tracks: For Training Multinational Managers
ERIC Educational Resources Information Center
Harvey, Michael G.; Kerin, Roger A.
1977-01-01
The problem of identifying and training college students to be effective multinational marketing managers is investigated in three parts: (1) Identification of multinational manager attributes, (2) selection of multinational managers, and (3) multiple "track" training programs. (TA)
Digital-Electronic/Optical Apparatus Would Recognize Targets
NASA Technical Reports Server (NTRS)
Scholl, Marija S.
1994-01-01
Proposed automatic target-recognition apparatus consists mostly of digital-electronic/optical cross-correlator that processes infrared images of targets. Infrared images of unknown targets correlated quickly with images of known targets. Apparatus incorporates some features of correlator described in "Prototype Optical Correlator for Robotic Vision System" (NPO-18451), and some of correlator described in "Compact Optical Correlator" (NPO-18473). Useful in robotic system; to recognize and track infrared-emitting, moving objects as variously shaped hot workpieces on conveyor belt.
Real-Time Occlusion Handling in Augmented Reality Based on an Object Tracking Approach
Tian, Yuan; Guan, Tao; Wang, Cheng
2010-01-01
To produce a realistic augmentation in Augmented Reality, the correct relative positions of real objects and virtual objects are very important. In this paper, we propose a novel real-time occlusion handling method based on an object tracking approach. Our method is divided into three steps: selection of the occluding object, object tracking and occlusion handling. The user selects the occluding object using an interactive segmentation method. The contour of the selected object is then tracked in the subsequent frames in real-time. In the occlusion handling step, all the pixels on the tracked object are redrawn on the unprocessed augmented image to produce a new synthesized image in which the relative position between the real and virtual object is correct. The proposed method has several advantages. First, it is robust and stable, since it remains effective when the camera is moved through large changes of viewing angles and volumes or when the object and the background have similar colors. Second, it is fast, since the real object can be tracked in real-time. Last, a smoothing technique provides seamless merging between the augmented and virtual object. Several experiments are provided to validate the performance of the proposed method. PMID:22319278
Network Level Association and Fusion of Kinematic and Attribute Information
2010-12-15
L. Svensson, ``More Ways to Track Closely-Spaced Targets Than You Wanted To Know or Tips For Not Pissing Off the Radar Operator So Much That He Turns...To Know or Tips For Not Pissing Off the Radar Operator So Much That He Turns Off the Track Display”, Proc. ONR-GTRI Workshop on Tracking, Santa Barbara
Studying visual attention using the multiple object tracking paradigm: A tutorial review.
Meyerhoff, Hauke S; Papenmeier, Frank; Huff, Markus
2017-07-01
Human observers are capable of tracking multiple objects among identical distractors based only on their spatiotemporal information. Since the first report of this ability in the seminal work of Pylyshyn and Storm (1988, Spatial Vision, 3, 179-197), multiple object tracking has attracted many researchers. A reason for this is that it is commonly argued that the attentional processes studied with the multiple object paradigm apparently match the attentional processing during real-world tasks such as driving or team sports. We argue that multiple object tracking provides a good mean to study the broader topic of continuous and dynamic visual attention. Indeed, several (partially contradicting) theories of attentive tracking have been proposed within the almost 30 years since its first report, and a large body of research has been conducted to test these theories. With regard to the richness and diversity of this literature, the aim of this tutorial review is to provide researchers who are new in the field of multiple object tracking with an overview over the multiple object tracking paradigm, its basic manipulations, as well as links to other paradigms investigating visual attention and working memory. Further, we aim at reviewing current theories of tracking as well as their empirical evidence. Finally, we review the state of the art in the most prominent research fields of multiple object tracking and how this research has helped to understand visual attention in dynamic settings.
ERIC Educational Resources Information Center
Jansen, E. P. W. A.; Suhre, C. J. M.
2015-01-01
This article studies the relationship between students' perceptions of teaching and learning in a multidisciplinary honours programme and their impact on graduate attributes acquisition. The study, conducted among 73 honours students in a Dutch research university, evaluates perceived improvement in graduate attributes through annually collected…
Object tracking using plenoptic image sequences
NASA Astrophysics Data System (ADS)
Kim, Jae Woo; Bae, Seong-Joon; Park, Seongjin; Kim, Do Hyung
2017-05-01
Object tracking is a very important problem in computer vision research. Among the difficulties of object tracking, partial occlusion problem is one of the most serious and challenging problems. To address the problem, we proposed novel approaches to object tracking on plenoptic image sequences. Our approaches take advantage of the refocusing capability that plenoptic images provide. Our approaches input the sequences of focal stacks constructed from plenoptic image sequences. The proposed image selection algorithms select the sequence of optimal images that can maximize the tracking accuracy from the sequence of focal stacks. Focus measure approach and confidence measure approach were proposed for image selection and both of the approaches were validated by the experiments using thirteen plenoptic image sequences that include heavily occluded target objects. The experimental results showed that the proposed approaches were satisfactory comparing to the conventional 2D object tracking algorithms.
Multi-Beam Approach for Accelerating Alignment and Calibration of HyspIRI-Like Imaging Spectrometers
NASA Technical Reports Server (NTRS)
Eastwood, Michael L.; Green, Robert O.; Mouroulis, Pantazis; Hochberg, Eric B.; Hein, Randall C.; Kroll, Linley A.; Geier, Sven; Coles, James B.; Meehan, Riley
2012-01-01
A paper describes an optical stimulus that produces more consistent results, and can be automated for unattended, routine generation of data analysis products needed by the integration and testing team assembling a high-fidelity imaging spectrometer system. One key attribute of the system is an arrangement of pick-off mirrors that provides multiple input beams (five in this implementation) to simultaneously provide stimulus light to several field angles along the field of view of the sensor under test, allowing one data set to contain all the information that previously required five data sets to be separately collected. This stimulus can also be fed by quickly reconfigured sources that ultimately provide three data set types that would previously be collected separately using three different setups: Spectral Response Function (SRF), Cross-track Response Function (CRF), and Along-track Response Function (ARF), respectively. This method also lends itself to expansion of the number of field points if less interpolation across the field of view is desirable. An absolute minimum of three is required at the beginning stages of imaging spectrometer alignment.
Extracting the temperature of hot carriers in time- and angle-resolved photoemission.
Ulstrup, Søren; Johannsen, Jens Christian; Grioni, Marco; Hofmann, Philip
2014-01-01
The interaction of light with a material's electronic system creates an out-of-equilibrium (non-thermal) distribution of optically excited electrons. Non-equilibrium dynamics relaxes this distribution on an ultrafast timescale to a hot Fermi-Dirac distribution with a well-defined temperature. The advent of time- and angle-resolved photoemission spectroscopy (TR-ARPES) experiments has made it possible to track the decay of the temperature of the excited hot electrons in selected states in the Brillouin zone, and to reveal their cooling in unprecedented detail in a variety of emerging materials. It is, however, not a straightforward task to determine the temperature with high accuracy. This is mainly attributable to an a priori unknown position of the Fermi level and the fact that the shape of the Fermi edge can be severely perturbed when the state in question is crossing the Fermi energy. Here, we introduce a method that circumvents these difficulties and accurately extracts both the temperature and the position of the Fermi level for a hot carrier distribution by tracking the occupation statistics of the carriers measured in a TR-ARPES experiment.
ERIC Educational Resources Information Center
Rattanarungrot, Sasithorn; White, Martin; Newbury, Paul
2014-01-01
This paper describes the design of our service-oriented architecture to support mobile multiple object tracking augmented reality applications applied to education and learning scenarios. The architecture is composed of a mobile multiple object tracking augmented reality client, a web service framework, and dynamic content providers. Tracking of…
NASA Technical Reports Server (NTRS)
Helfrich, Cliff; Berry, David S.; Bhat, Ramachandra; Border, James; Graat, Eric; Halsell, Allen; Kruizinga, Gerhard; Lau, Eunice; Mottinger, Neil; Rush, Brian;
2015-01-01
In late 2013, the Indian Space Research Organization (ISRO) launched its "Mars Orbiter Mission" (MOM). ISRO engaged NASA's Jet Propulsion Laboratory (JPL) for navigation services to support ISRO's objectives of MOM achieving and maintaining Mars orbit. The navigation support included planning, documentation, testing, orbit determination, maneuver design /analysis, and tracking data analysis. Several of MOM's attributes had an impact on navigation processes, e.g., S -band telecommunications, Earth Orbit Phase maneuvers, and frequent angular momentum desaturation s (AMDs). The primary source of tracking data was NASA/ JPL's Deep Space Network (DSN); JPL also conducted a performance assessment of Indian Deep Space Network (IDSN) tracking data. Planning for the Mars Orbit Insertion (MOI) was complicated by a pressure regulator failure that created uncertainty regarding MOM's main engine and raised potential planetary protection issues. A successful main engine test late on approach resolved these issues; it was quickly followed by a successful MOI on 24-September - 2014 at 02:00 UTC. Less than a month later, Comet Siding Spring's Mars flyby necessitated plans to minimize potential spacecraft damage. At the time of this writing, MOM's orbital operations continue, and plans to extend JPL 's support are in progress. This paper covers the JPL 's support of MOM through the Comet Siding Spring event.
Adopting ORCID as a unique identifier will benefit all involved in scholarly communication.
Arunachalam, Subbiah; Madhan, Muthu
2016-01-01
ORCID, the Open Researcher and Contributor ID, is a non- profit, community-driven effort to create and maintain a registry of unique researcher identifiers and a transparent method of linking research activities and outputs to these identifiers. Together with other persistent identifiers for scholarly works such as digital object identifiers (DOIs) and identifiers for organizations, ORCID makes research more discoverable. It helps ensure that one's grants, publications and outputs are correctly attributed. It helps the research community not just in aggregating publications, but in every stage of research, viz. publishing, reviewing, profiling, metrics, accessing and archiving. Funding agencies in Austria, Australia, Denmark, Portugal, Sweden and the UK, and the world's leading scholarly publishers and associations have integrated their systems with ORCID registry. Among the BRICS countries, China and South Africa are adopting ORCID avidly. India is yet to make a beginning. If research councils and funding agencies in India require researchers to adopt ORCID and link ORCID iDs to funding as well as tracking performance, it will help them keep track of the workflow. Journal editors can also keep track of contributions made by different authors and work assigned to different reviewers through their ORCID iDs.
Bae, Seung-Hwan; Yoon, Kuk-Jin
2018-03-01
Online multi-object tracking aims at estimating the tracks of multiple objects instantly with each incoming frame and the information provided up to the moment. It still remains a difficult problem in complex scenes, because of the large ambiguity in associating multiple objects in consecutive frames and the low discriminability between objects appearances. In this paper, we propose a robust online multi-object tracking method that can handle these difficulties effectively. We first define the tracklet confidence using the detectability and continuity of a tracklet, and decompose a multi-object tracking problem into small subproblems based on the tracklet confidence. We then solve the online multi-object tracking problem by associating tracklets and detections in different ways according to their confidence values. Based on this strategy, tracklets sequentially grow with online-provided detections, and fragmented tracklets are linked up with others without any iterative and expensive association steps. For more reliable association between tracklets and detections, we also propose a deep appearance learning method to learn a discriminative appearance model from large training datasets, since the conventional appearance learning methods do not provide rich representation that can distinguish multiple objects with large appearance variations. In addition, we combine online transfer learning for improving appearance discriminability by adapting the pre-trained deep model during online tracking. Experiments with challenging public datasets show distinct performance improvement over other state-of-the-arts batch and online tracking methods, and prove the effect and usefulness of the proposed methods for online multi-object tracking.
Automatic programming of arc welding robots
NASA Astrophysics Data System (ADS)
Padmanabhan, Srikanth
Automatic programming of arc welding robots requires the geometric description of a part from a solid modeling system, expert weld process knowledge and the kinematic arrangement of the robot and positioner automatically. Current commercial solid models are incapable of storing explicitly product and process definitions of weld features. This work presents a paradigm to develop a computer-aided engineering environment that supports complete weld feature information in a solid model and to create an automatic programming system for robotic arc welding. In the first part, welding features are treated as properties or attributes of an object, features which are portions of the object surface--the topological boundary. The structure for representing the features and attributes is a graph called the Welding Attribute Graph (WAGRAPH). The method associates appropriate weld features to geometric primitives, adds welding attributes, and checks the validity of welding specifications. A systematic structure is provided to incorporate welding attributes and coordinate system information in a CSG tree. The specific implementation of this structure using a hybrid solid modeler (IDEAS) and an object-oriented programming paradigm is described. The second part provides a comprehensive methodology to acquire and represent weld process knowledge required for the proper selection of welding schedules. A methodology of knowledge acquisition using statistical methods is proposed. It is shown that these procedures did little to capture the private knowledge of experts (heuristics), but helped in determining general dependencies, and trends. A need was established for building the knowledge-based system using handbook knowledge and to allow the experts further to build the system. A methodology to check the consistency and validity for such knowledge addition is proposed. A mapping shell designed to transform the design features to application specific weld process schedules is described. A new approach using fixed path modified continuation methods is proposed in the final section to plan continuously the trajectory of weld seams in an integrated welding robot and positioner environment. The joint displacement, velocity, and acceleration histories all along the path as a function of the path parameter for the best possible welding condition are provided for the robot and the positioner to track various paths normally encountered in arc welding.
GIS measured environmental correlates of active school transport: A systematic review of 14 studies
2011-01-01
Background Emerging frameworks to examine active school transportation (AST) commonly emphasize the built environment (BE) as having an influence on travel mode decisions. Objective measures of BE attributes have been recommended for advancing knowledge about the influence of the BE on school travel mode choice. An updated systematic review on the relationships between GIS-measured BE attributes and AST is required to inform future research in this area. The objectives of this review are: i) to examine and summarize the relationships between objectively measured BE features and AST in children and adolescents and ii) to critically discuss GIS methodologies used in this context. Methods Six electronic databases, and websites were systematically searched, and reference lists were searched and screened to identify studies examining AST in students aged five to 18 and reporting GIS as an environmental measurement tool. Fourteen cross-sectional studies were identified. The analyses were classified in terms of density, diversity, and design and further differentiated by the measures used or environmental condition examined. Results Only distance was consistently found to be negatively associated with AST. Consistent findings of positive or negative associations were not found for land use mix, residential density, and intersection density. Potential modifiers of any relationship between these attributes and AST included age, school travel mode, route direction (e.g., to/from school), and trip-end (home or school). Methodological limitations included inconsistencies in geocoding, selection of study sites, buffer methods and the shape of zones (Modifiable Areal Unit Problem [MAUP]), the quality of road and pedestrian infrastructure data, and school route estimation. Conclusions The inconsistent use of spatial concepts limits the ability to draw conclusions about the relationship between objectively measured environmental attributes and AST. Future research should explore standardizing buffer size, assess the quality of street network datasets and, if necessary, customize existing datasets, and explore further attributes linked to safety. PMID:21545750
NASA Astrophysics Data System (ADS)
Bertrand, Audrey; Pomella, Hannah; Fügenschuh, Bernhard; Zerlauth, Michael; Ortner, Hugo
2013-04-01
The study area in the westernmost part of Austria is marked by the limit between the Western and the Eastern Alps that takes place along the Rhine Valley, south of the Lake Constance. The area is composed, form the north to the south and from lowermost to uppermost structural position, by the European basement together with its autochthonous Mesozoic cover, autochthonous Molasse, subalpine Molasse, the Helvetic and Ultra-Helvetic, the Penninic and the Austroalpine nappes. These units are stacked in a succession of nappes separated by large south-trending overthrusts. This study presenting new apatite and zircon fission track ages, together with a crustal-scale cross-section (Pomella et al., this session) addresses the thermotectonic evolution of this nappe stack. In comparison with similar studies from eastern Switzerland the boundary between Western and Eastern Alps should be enlightened. Zircon fissions track ages from the lower freshwater Molasse reveal different age populations. Since all zircon fission track ages are older than the stratigraphic age this clearly indicates that post-depositional temperatures were well below the zircon partial annealing zone (i.e. below 200 °C) and the different age populations can be attributed to different source areas derived from the coevally forming and eroding alpine chain. Preliminary fission track results on apatite from the lower freshwater Molasse indicate a strong dependence of apatite fission track single-grain ages on their annealing kinetics as inferred from Dpar analyses (Gleadow and Duddy, 1981). F-rich apatites systematically yielded younger ages compared to the Cl-rich grains. The younger ages derived from the F-rich apatites are consistently younger than the stratigraphic age and thus fully annealed while Cl-rich apatites display older ages than the stratigraphic one. The difference in annealing temperatures between Cl- and F-rich apatites (Ravenhurst and Donelick, 1992) thus constrains the maximum temperature to < 100 °C, most likely reached between 20 Ma and 14 Ma by combined sediment and tectonic overburden. References Gleadow, A.J.W., and Duddy, I.R., 1981, A natural long-term annealing experiment for apatite. Nuclear Tracks Radiation Experiments, 5, 169-174. Pomella et al., this session. Alpine nappe stack in western Austria: A crustal-scale cross-section. Ravenhurst, C.E., and Donelick, R.A., 1992. Fission track thermochronology. In Short Course. Handbook on Low Temperature Thermochronology, ed. M. Zentilli & P.H. Reynolds. pp.21-42.
Advanced Microwave Radiometer (AMR) for SWOT mission
NASA Astrophysics Data System (ADS)
Chae, C. S.
2015-12-01
The objective of the SWOT (Surface Water & Ocean Topography) satellite mission is to measure wide-swath, high resolution ocean topography and terrestrial surface waters. Since main payload radar will use interferometric SAR technology, conventional microwave radiometer system which has single nadir look antenna beam (i.e., OSTM/Jason-2 AMR) is not ideally applicable for the mission for wet tropospheric delay correction. Therefore, SWOT AMR incorporates two antenna beams along cross track direction. In addition to the cross track design of the AMR radiometer, wet tropospheric error requirement is expressed in space frequency domain (in the sense of cy/km), in other words, power spectral density (PSD). Thus, instrument error allocation and design are being done in PSD which are not conventional approaches for microwave radiometer requirement allocation and design. A few of novel analyses include: 1. The effects of antenna beam size to PSD error and land/ocean contamination, 2. Receiver error allocation and the contributions of radiometric count averaging, NEDT, Gain variation, etc. 3. Effect of thermal design in the frequency domain. In the presentation, detailed AMR design and analyses results will be discussed.
The Identification and Tracking of Uterine Contractions Using Template Based Cross-Correlation.
McDonald, Sarah C; Brooker, Graham; Phipps, Hala; Hyett, Jon
2017-09-01
The purpose of this paper is to outline a novel method of using template based cross-correlation to identify and track uterine contractions during labour. A purpose built six-channel Electromyography (EMG) device was used to collect data from consenting women during labour and birth. A range of templates were constructed for the purpose of identifying and tracking uterine activity when cross-correlated with the EMG signal. Peak finding techniques were applied on the cross-correlated result to simplify and automate the identification and tracking of contractions. The EMG data showed a unique pattern when a woman was contracting with key features of the contraction signal remaining consistent and identifiable across subjects. Contraction profiles across subjects were automatically identified using template based cross-correlation. Synthetic templates from a rectangular function with a duration of between 5 and 10 s performed best at identifying and tracking uterine activity across subjects. The successful application of this technique provides opportunity for both simple and accurate real-time analysis of contraction data while enabling investigations into the application of techniques such as machine learning which could enable automated learning from contraction data as part of real-time monitoring and post analysis.
Lie, Arve; Skogstad, Marit; Johnsen, Torstein Seip; Engdahl, Bo; Tambs, Kristian
2014-10-16
Railway workers performing maintenance work of trains and tracks could be at risk of developing noise-induced hearing loss, since they are exposed to noise levels of 75-90 dB(A) with peak exposures of 130-140 dB(C). The objective was to make a risk assessment by comparing the hearing thresholds among train and track maintenance workers with a reference group not exposed to noise and reference values from the ISO 1999. Cross-sectional. A major Norwegian railway company. 1897 and 2730 male train and track maintenance workers, respectively, all exposed to noise, and 2872 male railway traffic controllers and office workers not exposed to noise. The primary outcome was the hearing threshold (pure tone audiometry, frequencies from 0.5 to 8 kHz), and the secondary outcome was the prevalence of audiometric notches (Coles notch) of the most recent audiogram. Train and track maintenance workers aged 45 years or older had a small mean hearing loss in the 3-6 kHz area of 3-5 dB. The hearing loss was less among workers younger than 45 years. Audiometric notches were slightly more prevalent among the noise exposed (59-64%) group compared with controls (49%) for all age groups. They may therefore be a sensitive measure in disclosing an early hearing loss at a group level. Train and track maintenance workers aged 45 years or older, on average, have a slightly greater hearing loss and more audiometric notches compared with reference groups not exposed to noise. Younger (<45 years) workers have hearing thresholds comparable to the controls. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Surviving track through Bridge No. 1601, Third B&O Crossing, looking ...
Surviving track through Bridge No. 1601, Third B&O Crossing, looking west. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD
Using galaxy pairs to investigate the three-point correlation function in the squeezed limit
NASA Astrophysics Data System (ADS)
Yuan, Sihan; Eisenstein, Daniel J.; Garrison, Lehman H.
2017-11-01
We investigate the three-point correlation function (3PCF) in the squeezed limit by considering galaxy pairs as discrete objects and cross-correlating them with the galaxy field. We develop an efficient algorithm using fast Fourier transforms to compute such cross-correlations and their associated pair-galaxy bias bp, g and the squeezed 3PCF coefficient Qeff. We implement our method using N-body cosmological simulations and a fiducial halo occupation distribution (HOD) and present the results in both the real space and redshift space. In real space, we observe a peak in bp, g and Qeff at pair separation of ∼2 Mpc, attributed to the fact that galaxy pairs at 2 Mpc separation trace the most massive dark matter haloes. We also see strong anisotropy in the bp, g and Qeff signals that track the large-scale filamentary structure. In redshift space, both the 2 Mpc peak and the anisotropy are significantly smeared out along the line of sight due to finger-of-God effect. In both the real space and redshift space, the squeezed 3PCF shows a factor of 2 variation, contradicting the hierarchical ansatz, but offering rich information on the galaxy-halo connection. Thus, we explore the possibility of using the squeezed 3PCF to constrain the HOD. When we compare two simple HOD models that are closely matched in their projected two-point correlation function (2PCF), we do not yet see a strong variation in the 3PCF that is clearly disentangled from variations in the projected 2PCF. Nevertheless, we propose that more complicated HOD models, e.g. those incorporating assembly bias, can break degeneracies in the 2PCF and show a distinguishable squeezed 3PCF signal.
Adaptive learning compressive tracking based on Markov location prediction
NASA Astrophysics Data System (ADS)
Zhou, Xingyu; Fu, Dongmei; Yang, Tao; Shi, Yanan
2017-03-01
Object tracking is an interdisciplinary research topic in image processing, pattern recognition, and computer vision which has theoretical and practical application value in video surveillance, virtual reality, and automatic navigation. Compressive tracking (CT) has many advantages, such as efficiency and accuracy. However, when there are object occlusion, abrupt motion and blur, similar objects, and scale changing, the CT has the problem of tracking drift. We propose the Markov object location prediction to get the initial position of the object. Then CT is used to locate the object accurately, and the classifier parameter adaptive updating strategy is given based on the confidence map. At the same time according to the object location, extract the scale features, which is able to deal with object scale variations effectively. Experimental results show that the proposed algorithm has better tracking accuracy and robustness than current advanced algorithms and achieves real-time performance.
Improving GOCE cross-track gravity gradients
NASA Astrophysics Data System (ADS)
Siemes, Christian
2018-01-01
The GOCE gravity gradiometer measured highly accurate gravity gradients along the orbit during GOCE's mission lifetime from March 17, 2009, to November 11, 2013. These measurements contain unique information on the gravity field at a spatial resolution of 80 km half wavelength, which is not provided to the same accuracy level by any other satellite mission now and in the foreseeable future. Unfortunately, the gravity gradient in cross-track direction is heavily perturbed in the regions around the geomagnetic poles. We show in this paper that the perturbing effect can be modeled accurately as a quadratic function of the non-gravitational acceleration of the satellite in cross-track direction. Most importantly, we can remove the perturbation from the cross-track gravity gradient to a great extent, which significantly improves the accuracy of the latter and offers opportunities for better scientific exploitation of the GOCE gravity gradient data set.
PHAROS: Shedding Light on the Near-Earth Asteroid Apophis
NASA Technical Reports Server (NTRS)
Sharma, Jonathan; Lafleur, Jarret; Barron, Kreston; Townley, Jonathan; Shah, Nilesh; Apa, Jillian
2007-01-01
The Pharos mission to asteroid Apophis provides the first major opportunity to enhance orbital state and scientific knowledge of the most threatening Earth-crossing asteroid that has ever been tracked. Pharos aims to accomplish concrete and feasible orbit determination and scientific objectives while achieving balance among mission cost, nsk,and schedule. Similar to its ancient Egyptian namesake, Pharos acts as a beacon shedding light not only on the physical characteristics of Apophis, but also on its state as it travels through the solar system.
Khan, Zulfiqar Hasan; Gu, Irene Yu-Hua
2013-12-01
This paper proposes a novel Bayesian online learning and tracking scheme for video objects on Grassmann manifolds. Although manifold visual object tracking is promising, large and fast nonplanar (or out-of-plane) pose changes and long-term partial occlusions of deformable objects in video remain a challenge that limits the tracking performance. The proposed method tackles these problems with the main novelties on: 1) online estimation of object appearances on Grassmann manifolds; 2) optimal criterion-based occlusion handling for online updating of object appearances; 3) a nonlinear dynamic model for both the appearance basis matrix and its velocity; and 4) Bayesian formulations, separately for the tracking process and the online learning process, that are realized by employing two particle filters: one is on the manifold for generating appearance particles and another on the linear space for generating affine box particles. Tracking and online updating are performed in an alternating fashion to mitigate the tracking drift. Experiments using the proposed tracker on videos captured by a single dynamic/static camera have shown robust tracking performance, particularly for scenarios when target objects contain significant nonplanar pose changes and long-term partial occlusions. Comparisons with eight existing state-of-the-art/most relevant manifold/nonmanifold trackers with evaluations have provided further support to the proposed scheme.
A Micromagnetic Study of Medium Orientation Ratio Effects in High Areal Density Recording
NASA Astrophysics Data System (ADS)
Plumer, Martin; van Ek, Johannes
2000-03-01
An extensive analysis of written tracks on granular media with anisotropy axes preferentially oriented either in the down-track or cross-track direction was performed with a newly developed micromagnetic model of magnetic recording [1]. The response of planar media to writer head fields, derived from the Finite-Element-Method, is calculated by solving the LLG equations. Signal from the written transitions is determined through a micromagnetic model of a GMR spin-valve device. Using fields from a generic 10Gb/in2 head (TPWG=0.6um, gap=0.2um, 1.8T materials around the gap), dibits were written at high linear density. Relative to the isotropic case, both erase bands and read-back voltage deteriorate for cross-track oriented media and improve in the down-track orientation case. For an orientation ratio of 1.23, the read-back signal at 200 kbpi drops by 15% in the radial case and increases by 15% in the circumferential case. Although the cross-track coercivity is smaller for down-track oriented media, and thus easier to write with the corners of the head, the remnant cross-track magnetization is correspondingly smaller. Track edge distortion is thus less severe than for isotropic media. Oriented media is of interest due to enhanced thermal stability and faster switching times [2]. [1] J. van Ek, M.L. Plumer, H. Zhou and H.N. Bertram, ``A Micromagnetic Recording Model for Write and Read-back," in preparation. Also see the GMAG symposium, this conference. [2] E.N. Abarra, I. Okamoto and M. Shinohara, IEEE Trans. Mag. 35, 2709 (1999).
Cross-calibration between airborne SAR sensors
NASA Technical Reports Server (NTRS)
Zink, Manfred; Olivier, Philippe; Freeman, Anthony
1993-01-01
As Synthetic Aperture Radar (SAR) system performance and experience in SAR signature evaluation increase, quantitative analysis becomes more and more important. Such analyses require an absolute radiometric calibration of the complete SAR system. To keep the expenditure on calibration of future multichannel and multisensor remote sensing systems (e.g., X-SAR/SIR-C) within a tolerable level, data from different tracks and different sensors (channels) must be cross calibrated. The 1989 joint E-SAR/DC-8 SAR calibration campaign gave a first opportunity for such an experiment, including cross sensor and cross track calibration. A basic requirement for successful cross calibration is the stability of the SAR systems. The calibration parameters derived from different tracks and the polarimetric properties of the uncalibrated data are used to describe this stability. Quality criteria for a successful cross calibration are the agreement of alpha degree values and the consistency of radar cross sections of equally sized corner reflectors. Channel imbalance and cross talk provide additional quality in case of the polarimetric DC-8 SAR.
Multiple objects tracking in fluorescence microscopy.
Kalaidzidis, Yannis
2009-01-01
Many processes in cell biology are connected to the movement of compact entities: intracellular vesicles and even single molecules. The tracking of individual objects is important for understanding cellular dynamics. Here we describe the tracking algorithms which have been developed in the non-biological fields and successfully applied to object detection and tracking in biological applications. The characteristics features of the different algorithms are compared.
ERIC Educational Resources Information Center
Ferrara, Katrina; Hoffman, James E.; O'Hearn, Kirsten; Landau, Barbara
2016-01-01
The ability to track moving objects is a crucial skill for performance in everyday spatial tasks. The tracking mechanism depends on representation of moving items as coherent entities, which follow the spatiotemporal constraints of objects in the world. In the present experiment, participants tracked 1 to 4 targets in a display of 8 identical…
Tracking cross-contamination transfer dynamics at a mock retail deli market using GloGerm.
Maitland, Jessica; Boyer, Renee; Gallagher, Dan; Duncan, Susan; Bauer, Nate; Kause, Janell; Eifert, Joseph
2013-02-01
Ready-to-eat (RTE) deli meats are considered a food at high risk for causing foodborne illness. Deli meats are listed as the highest risk RTE food vehicle for Listeria monocytogenes. Cross-contamination in the retail deli market may contribute to spread of pathogens to deli meats. Understanding potential cross-contamination pathways is essential for reducing the risk of contaminating various products. The objective of this study was to track cross-contamination pathways through a mock retail deli market using an abiotic surrogate, GloGerm, to visually represent how pathogens may spread through the deli environment via direct contact with food surfaces. Six contamination origination sites (slicer blade, meat chub, floor drain, preparation table, employee's glove, and employee's hands) were evaluated separately. Each site was inoculated with 20 ml of GloGerm, and a series of standard deli operations were completed (approximately 10 min of work). Photographs were then taken under UV illumination to visualize spread of GloGerm throughout the deli. A sensory panel evaluated the levels of contamination on the resulting contaminated surfaces. Five of the six contamination origination sites were associated with transfer of GloGerm to the deli case door handle, slicer blade, meat chub, preparation table, and the employee's gloves. Additional locations became contaminated (i.e., deli case shelf, prep table sink, and glove box), but this contamination was not consistent across all trials. Contamination did not spread from the floor drain to any food contact surfaces. The findings of this study reinforce the need for consistent equipment cleaning and food safety practices among deli workers to minimize cross-contamination.
NASA Technical Reports Server (NTRS)
Eby, P. B.; Morgan, S. H.; Parnell, T. A.
1978-01-01
Energy deposition due to secondary electrons is calculated as a function of distance from the axis of the track of a heavy ion. The calculation incorporates the empirical formulas of Kobetich and Katz (1968) for delta-ray energy dissipation. Both the Mott and Born-approximation expressions for the delta-ray energy distributions are used, and the results are compared. The energy deposition projected along a line perpendicular to the track is also calculated. These results are used to estimate the effect that the use of the Mott cross section would have in the interpretation of photometric measurements on emulsion tracks of trans-iron cosmic-ray particles. It is shown that the use of 50 keV as a characteristic track-formation electron energy to estimate the effect of the Mott cross section systematically overestimates charge as derived from emulsions for Z greater than 20.
NASA Astrophysics Data System (ADS)
Chen, Xiao; Li, Yaan; Yu, Jing; Li, Yuxing
2018-01-01
For fast and more effective implementation of tracking multiple targets in a cluttered environment, we propose a multiple targets tracking (MTT) algorithm called maximum entropy fuzzy c-means clustering joint probabilistic data association that combines fuzzy c-means clustering and the joint probabilistic data association (PDA) algorithm. The algorithm uses the membership value to express the probability of the target originating from measurement. The membership value is obtained through fuzzy c-means clustering objective function optimized by the maximum entropy principle. When considering the effect of the public measurement, we use a correction factor to adjust the association probability matrix to estimate the state of the target. As this algorithm avoids confirmation matrix splitting, it can solve the high computational load problem of the joint PDA algorithm. The results of simulations and analysis conducted for tracking neighbor parallel targets and cross targets in a different density cluttered environment show that the proposed algorithm can realize MTT quickly and efficiently in a cluttered environment. Further, the performance of the proposed algorithm remains constant with increasing process noise variance. The proposed algorithm has the advantages of efficiency and low computational load, which can ensure optimum performance when tracking multiple targets in a dense cluttered environment.
Blood Lead Levels and Health Problems of Lead Acid Battery Workers in Bangladesh
Ahmad, Sk. Akhtar; Khan, Manzurul Haque; Khandker, Salamat; Sarwar, A. F. M.; Yasmin, Nahid; Faruquee, M. H.; Yasmin, Rabeya
2014-01-01
Introduction. Use of lead acid battery (LAB) in Bangladesh has risen with sharp rise of motor vehicles. As result, manufacture of LAB is increasing. Most of the lead used by these industries comes from recycling of LAB. Workers in LAB industry are at risk of exposure lead and thus development of lead toxicity. Objective. The objective of this study was to measure the blood lead concentration and to assess the magnitude of health problems attributable to lead toxicity among the LAB manufacturing workers. Methods. A cross-sectional study was conducted among the workers of LAB manufacturing industries located in Dhaka city. Result. Mean blood lead level (BLL) among the workers was found to be high. They were found to be suffering from a number of illnesses attributable to lead toxicity. The common illnesses were frequent headache, numbness of the limbs, colic pain, nausea, tremor, and lead line on the gum. High BLL was also found to be related to hypertension and anemia of the workers. Conclusion. High BLL and illnesses attributable to lead toxicity were prevalent amongst workers of the LAB manufacturing industries, and this requires attention especially in terms of occupational hygiene and safety. PMID:24707223
Qin, Lei; Snoussi, Hichem; Abdallah, Fahed
2014-01-01
We propose a novel approach for tracking an arbitrary object in video sequences for visual surveillance. The first contribution of this work is an automatic feature extraction method that is able to extract compact discriminative features from a feature pool before computing the region covariance descriptor. As the feature extraction method is adaptive to a specific object of interest, we refer to the region covariance descriptor computed using the extracted features as the adaptive covariance descriptor. The second contribution is to propose a weakly supervised method for updating the object appearance model during tracking. The method performs a mean-shift clustering procedure among the tracking result samples accumulated during a period of time and selects a group of reliable samples for updating the object appearance model. As such, the object appearance model is kept up-to-date and is prevented from contamination even in case of tracking mistakes. We conducted comparing experiments on real-world video sequences, which confirmed the effectiveness of the proposed approaches. The tracking system that integrates the adaptive covariance descriptor and the clustering-based model updating method accomplished stable object tracking on challenging video sequences. PMID:24865883
Curvature and torsion in growing actin networks
NASA Astrophysics Data System (ADS)
Shaevitz, Joshua W.; Fletcher, Daniel A.
2008-06-01
Intracellular pathogens such as Listeria monocytogenes and Rickettsia rickettsii move within a host cell by polymerizing a comet-tail of actin fibers that ultimately pushes the cell forward. This dense network of cross-linked actin polymers typically exhibits a striking curvature that causes bacteria to move in gently looping paths. Theoretically, tail curvature has been linked to details of motility by considering force and torque balances from a finite number of polymerizing filaments. Here we track beads coated with a prokaryotic activator of actin polymerization in three dimensions to directly quantify the curvature and torsion of bead motility paths. We find that bead paths are more likely to have low rather than high curvature at any given time. Furthermore, path curvature changes very slowly in time, with an autocorrelation decay time of 200 s. Paths with a small radius of curvature, therefore, remain so for an extended period resulting in loops when confined to two dimensions. When allowed to explore a three-dimensional (3D) space, path loops are less evident. Finally, we quantify the torsion in the bead paths and show that beads do not exhibit a significant left- or right-handed bias to their motion in 3D. These results suggest that paths of actin-propelled objects may be attributed to slow changes in curvature, possibly associated with filament debranching, rather than a fixed torque.
UMass at TREC 2002: Cross Language and Novelty Tracks
2002-01-01
resources – stemmers, dictionaries , machine translation, and an acronym database. We found that proper names were extremely important in this year’s queries...data by manually annotating 48 additional topics. 1. Cross Language Track We submitted one monolingual run and four cross-language runs. For the... monolingual run, the technology was essentially the same as the system we used for TREC 2001. For the cross-language run, we integrated some new
Statistical Representations of Track Geometry : Volume I, Text.
DOT National Transportation Integrated Search
1980-03-31
Mathematical representations of railroad track geometry variations are derived from time series analyses of track measurements. Since the majority of track is free of anomalies (turnouts, crossings, bridges, etc.), representation of anomaly-free trac...
Risk Management of Jettisoned Objects in LEO
NASA Technical Reports Server (NTRS)
Bacon, John B.; Gray, Charles
2011-01-01
The construction and maintenance of the International Space Station (ISS) has led to the release of many objects into its orbital plane, usually during the course of an extra-vehicular activity (EVA). Such releases are often unintentional, but in a growing number of cases, the jettison has been intentional, conducted after a careful assessment of the net risk to the partnership and to other objects in space. Since its launch in 1998 the ISS has contributed on average at least one additional debris object that is simultaneously in orbit with the station, although the number varies widely from zero to eight at any one moment. All of these objects present potential risks to other objects in orbit. Whether it comes from known and tracked orbiting objects or from unknown or untrackable objects, collision with orbital debris can have disastrous consequences. Objects greater than 10cm are generally well documented and tracked, allowing orbiting spacecraft or satellites opportunities to perform evasive maneuvers (commonly known as Debris Avoidance Maneuvers, or DAMs) in the event that imminent collision is predicted. The issue with smaller debris; however, is that it is too numerous to be tracked effectively and yet still poses disastrous consequences if it intercepts a larger object. Due to the immense kinetic energy of any item in orbit, collision with debris as small as 1cm can have catastrophic consequences for many orbiting satellites or spacecraft. Faced with the growing orbital debris threat and the potentially catastrophic consequences of a collision-generated debris shower originating in an orbit crossing the ISS altitude band, in 2007 the ISS program manger asked program specialists to coordinate a multilateral jettison policy amongst the ISS partners. This policy would define the acceptable risk trade rationale for intentional release of a debris object, and other mandatory constraints on such jettisons to minimize the residual risks whenever a jettison was accepted. Although ISS-related debris often presents untenable risks to the EVA crew, IVA crew, or to a departing cargo vehicle for a controlled disposal, such released objects also present a ballistic nuisance to the visiting vehicle traffic, and a potential fragmentation threat to the hundreds of other functional and debris objects whose perigees lie below the ISS orbital altitude. Thus, every such jettison decision is a conscious risk trade.
Using Debate Skills to Engage Students in Astronomy
NASA Astrophysics Data System (ADS)
Karsten, Anna
2016-04-01
To increase the excitement for the astronomy unit and to expose the subject in all of its weird glory, students debate each other in a bracket style tournament defending their idea of the coolest object in the universe. At the start of May, causing the name of this event to be called May Madness, students choose an object or concept in the universe to research and construct an opening argument on how it is the coolest object in the universe. Every student in the eighth grade selects an object and proceeds to debate its attributes in a head-to-head competition leading to a class winner. The class winners then debate in front of the grade with celebrity guest judges. In the four minute debate, two students defend, cross examine, and construct a rebuttal for their chosen object.
Hardware accelerator design for tracking in smart camera
NASA Astrophysics Data System (ADS)
Singh, Sanjay; Dunga, Srinivasa Murali; Saini, Ravi; Mandal, A. S.; Shekhar, Chandra; Vohra, Anil
2011-10-01
Smart Cameras are important components in video analysis. For video analysis, smart cameras needs to detect interesting moving objects, track such objects from frame to frame, and perform analysis of object track in real time. Therefore, the use of real-time tracking is prominent in smart cameras. The software implementation of tracking algorithm on a general purpose processor (like PowerPC) could achieve low frame rate far from real-time requirements. This paper presents the SIMD approach based hardware accelerator designed for real-time tracking of objects in a scene. The system is designed and simulated using VHDL and implemented on Xilinx XUP Virtex-IIPro FPGA. Resulted frame rate is 30 frames per second for 250x200 resolution video in gray scale.
Gonzalez, Brian D; Small, Brent J; Cases, Mallory G; Williams, Noelle L; Fishman, Mayer N; Jacobsen, Paul B; Jim, Heather S L
2018-02-01
Patients with prostate cancer receiving androgen deprivation therapy (ADT) are at risk of sleep disturbance; however, to the authors' knowledge, the mechanisms by which ADT may affect sleep are not well understood. The current study compared objective and subjective sleep disturbance in ADT recipients and controls and examined whether sleep disturbance in ADT recipients is attributable to the influence of ADT on hot flashes and nocturia. Patients with prostate cancer were assessed before or within 1 month after the initiation of ADT as well as 6 months and 12 months later (78 patients). Patients with prostate cancer were treated with prostatectomy only (99 patients) and men with no history of cancer (108 men) were assessed at similar intervals. Participants self-reported their sleep disturbance (Insomnia Severity Index) and interference from hot flashes (Hot Flash Related Daily Interference Scale). One hundred participants also wore actigraphs for 3 days at the 6-month assessment to measure objective sleep disturbance and reported their nocturia frequency. ADT recipients reported worse sleep disturbance, higher rates of clinically significant sleep disturbance, and greater hot flash interference than controls (Ps≤.03). In cross-sectional analyses among those with actigraphy data, ADT recipients had greater objective sleep disturbance and more episodes of nocturia (Ps<.01). Cross-sectional mediation analyses demonstrated that the association between ADT and objectively and subjectively measured sleep disturbance was partly attributable to nocturia and hot flashes (Ps<.05). The results of the current study suggest that the association between ADT and sleep may be partly explained by nocturia and hot flash interference. Future studies should examine behavioral and pharmacologic interventions to address these symptoms among ADT recipients. Cancer 2018;124:499-506. © 2017 American Cancer Society. © 2017 American Cancer Society.
Evidence against a speed limit in multiple-object tracking.
Franconeri, S L; Lin, J Y; Pylyshyn, Z W; Fisher, B; Enns, J T
2008-08-01
Everyday tasks often require us to keep track of multiple objects in dynamic scenes. Past studies show that tracking becomes more difficult as objects move faster. In the present study, we show that this trade-off may not be due to increased speed itself but may, instead, be due to the increased crowding that usually accompanies increases in speed. Here, we isolate changes in speed from variations in crowding, by projecting a tracking display either onto a small area at the center of a hemispheric projection dome or onto the entire dome. Use of the larger display increased retinal image size and object speed by a factor of 4 but did not increase interobject crowding. Results showed that tracking accuracy was equally good in the large-display condition, even when the objects traveled far into the visual periphery. Accuracy was also not reduced when we tested object speeds that limited performance in the small-display condition. These results, along with a reinterpretation of past studies, suggest that we might be able to track multiple moving objects as fast as we can a single moving object, once the effect of object crowding is eliminated.
Brain Activation during Spatial Updating and Attentive Tracking of Moving Targets
ERIC Educational Resources Information Center
Jahn, Georg; Wendt, Julia; Lotze, Martin; Papenmeier, Frank; Huff, Markus
2012-01-01
Keeping aware of the locations of objects while one is moving requires the updating of spatial representations. As long as the objects are visible, attentional tracking is sufficient, but knowing where objects out of view went in relation to one's own body involves an updating of spatial working memory. Here, multiple object tracking was employed…
Ground radar detection of meteoroids in space
NASA Technical Reports Server (NTRS)
Kessler, D. J.; Landry, P. M.; Gabbard, J. R.; Moran, J. L. T.
1980-01-01
A special test to lower the detection threshold for satellite fragments potentially dangerous to spacecraft was carried out by NORAD for NASA, using modified radar software. The Perimeter Acquisition Radar Attack Characterization System, a large, planar face, phased radar, operates at a nominal 430 MHz and produces 120 pulses per second, 45 of which were dedicated to search. In a time period of 8.4 hours of observations over three days, over 6000 objects were detected and tracked of which 37 were determined to have velocities greater than escape velocity. Six of these were larger objects with radar cross sections greater than 0.1 sq m and were probably orbiting satellites. A table gives the flux of both observed groups.
A coarse-to-fine kernel matching approach for mean-shift based visual tracking
NASA Astrophysics Data System (ADS)
Liangfu, L.; Zuren, F.; Weidong, C.; Ming, J.
2009-03-01
Mean shift is an efficient pattern match algorithm. It is widely used in visual tracking fields since it need not perform whole search in the image space. It employs gradient optimization method to reduce the time of feature matching and realize rapid object localization, and uses Bhattacharyya coefficient as the similarity measure between object template and candidate template. This thesis presents a mean shift algorithm based on coarse-to-fine search for the best kernel matching. This paper researches for object tracking with large motion area based on mean shift. To realize efficient tracking of such an object, we present a kernel matching method from coarseness to fine. If the motion areas of the object between two frames are very large and they are not overlapped in image space, then the traditional mean shift method can only obtain local optimal value by iterative computing in the old object window area, so the real tracking position cannot be obtained and the object tracking will be disabled. Our proposed algorithm can efficiently use a similarity measure function to realize the rough location of motion object, then use mean shift method to obtain the accurate local optimal value by iterative computing, which successfully realizes object tracking with large motion. Experimental results show its good performance in accuracy and speed when compared with background-weighted histogram algorithm in the literature.
Computational methods to predict railcar response to track cross-level variations
DOT National Transportation Integrated Search
1976-09-01
The rocking response of railroad freight cars to track cross-level variations is studied using: (1) a reduced complexity digital simulation model, and (2) a quasi-linear describing function analysis. The reduced complexity digital simulation model em...
17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING ...
17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING OVER SETTLING BASIN, SPARE BENT MATERIAL IN RIGHT-HAND FOREGROUND, BYPASS FLUME, AND SHACK #6 IN BACKGROUND, LOOKING NORTHWEST - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA
Auto-steering apparatus and method
McKay, Mark D.; Anderson, Matthew O.
2007-03-13
A vehicular guidance method involves providing a user interface using which data can be input to establish a contour for a vehicle to follow, the user interface further configured to receive information from a differential global positioning system (DGPS), determining cross track and offset data using information received from the DGPS, generating control values, using at least vehicular kinematics, the cross track, and the offset data, and providing an output to control steering of the vehicle, using the control values, in a direction to follow the established contour while attempting to minimize the cross track and the offset data.
Fusion of Cross-Track TerraSAR-X PS Point Clouds over Las Vegas
NASA Astrophysics Data System (ADS)
Wang, Ziyun; Balz, Timo; Wei, Lianhuan; Liao, Mingsheng
2014-11-01
Persistent scatterer interferometry (PS-InSAR) is widely used in radar remote sensing. However, because the surface motion is estimated in the line-of-sight (LOS) direction, it is not possible to differentiate between vertical and horizontal surface motions from a single stack. Cross-track data, i.e. the combination of data from ascending and descending orbits, allows us to better analyze the deformation and to obtain 3d motion information. We implemented a cross-track fusion of PS-InSAR point cloud data, making it possible to separate the vertical and horizontal components of the surface motion.
Correlation and 3D-tracking of objects by pointing sensors
Griesmeyer, J. Michael
2017-04-04
A method and system for tracking at least one object using a plurality of pointing sensors and a tracking system are disclosed herein. In a general embodiment, the tracking system is configured to receive a series of observation data relative to the at least one object over a time base for each of the plurality of pointing sensors. The observation data may include sensor position data, pointing vector data and observation error data. The tracking system may further determine a triangulation point using a magnitude of a shortest line connecting a line of sight value from each of the series of observation data from each of the plurality of sensors to the at least one object, and perform correlation processing on the observation data and triangulation point to determine if at least two of the plurality of sensors are tracking the same object. Observation data may also be branched, associated and pruned using new incoming observation data.
On-track testing of a power harvesting device for railroad track health monitoring
NASA Astrophysics Data System (ADS)
Hansen, Sean E.; Pourghodrat, Abolfazl; Nelson, Carl A.; Fateh, Mahmood
2010-03-01
A considerable proportion of railroad infrastructure exists in regions which are comparatively remote. With regard to the cost of extending electrical infrastructure into these areas, road crossings in these areas do not have warning light systems or crossing gates and are commonly marked with reflective signage. For railroad track health monitoring purposes, distributed sensor networks can be applicable in remote areas, but the same limitation regarding electrical infrastructure is the hindrance. This motivated the development of an energy harvesting solution for remote railroad deployment. This paper describes on-track experimental testing of a mechanical device for harvesting mechanical power from passing railcar traffic, in view of supplying electrical power to warning light systems at crossings and to remote networks of sensors. The device is mounted to and spans two rail ties and transforms the vertical rail displacement into electrical energy through mechanical amplification and rectification into a PMDC generator. A prototype was tested under loaded and unloaded railcar traffic at low speeds. Stress analysis and speed scaling analysis are presented, results of the on-track tests are compared and contrasted to previous laboratory testing, discrepancies between the two are explained, and conclusions are drawn regarding suitability of the device for illuminating high-efficiency LED lights at railroad crossings and powering track-health sensor networks.
Romero, Veronica; Amaral, Joseph; Fitzpatrick, Paula; Schmidt, R C; Duncan, Amie W; Richardson, Michael J
2017-04-01
Functionally stable and robust interpersonal motor coordination has been found to play an integral role in the effectiveness of social interactions. However, the motion-tracking equipment required to record and objectively measure the dynamic limb and body movements during social interaction has been very costly, cumbersome, and impractical within a non-clinical or non-laboratory setting. Here we examined whether three low-cost motion-tracking options (Microsoft Kinect skeletal tracking of either one limb or whole body and a video-based pixel change method) can be employed to investigate social motor coordination. Of particular interest was the degree to which these low-cost methods of motion tracking could be used to capture and index the coordination dynamics that occurred between a child and an experimenter for three simple social motor coordination tasks in comparison to a more expensive, laboratory-grade motion-tracking system (i.e., a Polhemus Latus system). Overall, the results demonstrated that these low-cost systems cannot substitute the Polhemus system in some tasks. However, the lower-cost Microsoft Kinect skeletal tracking and video pixel change methods were successfully able to index differences in social motor coordination in tasks that involved larger-scale, naturalistic whole body movements, which can be cumbersome and expensive to record with a Polhemus. However, we found the Kinect to be particularly vulnerable to occlusion and the pixel change method to movements that cross the video frame midline. Therefore, particular care needs to be taken in choosing the motion-tracking system that is best suited for the particular research.
Cooperative multisensor system for real-time face detection and tracking in uncontrolled conditions
NASA Astrophysics Data System (ADS)
Marchesotti, Luca; Piva, Stefano; Turolla, Andrea; Minetti, Deborah; Regazzoni, Carlo S.
2005-03-01
The presented work describes an innovative architecture for multi-sensor distributed video surveillance applications. The aim of the system is to track moving objects in outdoor environments with a cooperative strategy exploiting two video cameras. The system also exhibits the capacity of focusing its attention on the faces of detected pedestrians collecting snapshot frames of face images, by segmenting and tracking them over time at different resolution. The system is designed to employ two video cameras in a cooperative client/server structure: the first camera monitors the entire area of interest and detects the moving objects using change detection techniques. The detected objects are tracked over time and their position is indicated on a map representing the monitored area. The objects" coordinates are sent to the server sensor in order to point its zooming optics towards the moving object. The second camera tracks the objects at high resolution. As well as the client camera, this sensor is calibrated and the position of the object detected on the image plane reference system is translated in its coordinates referred to the same area map. In the map common reference system, data fusion techniques are applied to achieve a more precise and robust estimation of the objects" track and to perform face detection and tracking. The work novelties and strength reside in the cooperative multi-sensor approach, in the high resolution long distance tracking and in the automatic collection of biometric data such as a person face clip for recognition purposes.
Policy reconciliation for access control in dynamic cross-enterprise collaborations
NASA Astrophysics Data System (ADS)
Preuveneers, D.; Joosen, W.; Ilie-Zudor, E.
2018-03-01
In dynamic cross-enterprise collaborations, different enterprises form a - possibly temporary - business relationship. To integrate their business processes, enterprises may need to grant each other limited access to their information systems. Authentication and authorization are key to secure information handling. However, access control policies often rely on non-standardized attributes to describe the roles and permissions of their employees which convolutes cross-organizational authorization when business relationships evolve quickly. Our framework addresses the managerial overhead of continuous updates to access control policies for enterprise information systems to accommodate disparate attribute usage. By inferring attribute relationships, our framework facilitates attribute and policy reconciliation, and automatically aligns dynamic entitlements during the evaluation of authorization decisions. We validate our framework with a Industry 4.0 motivating scenario on networked production where such dynamic cross-enterprise collaborations are quintessential. The evaluation reveals the capabilities and performance of our framework, and illustrates the feasibility of liberating the security administrator from manually provisioning and aligning attributes, and verifying the consistency of access control policies for cross-enterprise collaborations.
Multi-Complementary Model for Long-Term Tracking
Zhang, Deng; Zhang, Junchang; Xia, Chenyang
2018-01-01
In recent years, video target tracking algorithms have been widely used. However, many tracking algorithms do not achieve satisfactory performance, especially when dealing with problems such as object occlusions, background clutters, motion blur, low illumination color images, and sudden illumination changes in real scenes. In this paper, we incorporate an object model based on contour information into a Staple tracker that combines the correlation filter model and color model to greatly improve the tracking robustness. Since each model is responsible for tracking specific features, the three complementary models combine for more robust tracking. In addition, we propose an efficient object detection model with contour and color histogram features, which has good detection performance and better detection efficiency compared to the traditional target detection algorithm. Finally, we optimize the traditional scale calculation, which greatly improves the tracking execution speed. We evaluate our tracker on the Object Tracking Benchmarks 2013 (OTB-13) and Object Tracking Benchmarks 2015 (OTB-15) benchmark datasets. With the OTB-13 benchmark datasets, our algorithm is improved by 4.8%, 9.6%, and 10.9% on the success plots of OPE, TRE and SRE, respectively, in contrast to another classic LCT (Long-term Correlation Tracking) algorithm. On the OTB-15 benchmark datasets, when compared with the LCT algorithm, our algorithm achieves 10.4%, 12.5%, and 16.1% improvement on the success plots of OPE, TRE, and SRE, respectively. At the same time, it needs to be emphasized that, due to the high computational efficiency of the color model and the object detection model using efficient data structures, and the speed advantage of the correlation filters, our tracking algorithm could still achieve good tracking speed. PMID:29425170
Tomonari, H; Ikemori, T; Kubota, T; Uehara, S; Miyawaki, S
2014-12-01
A posterior cross-bite is defined as an abnormal bucco-lingual relationship between opposing molars, pre-molars or both in centric occlusion. Although it has been reported that patients with unilateral posterior cross-bite often show unique chewing patterns, the relationship between the form of cross-bite and masticatory jaw movement remains unclear in adult patients. The objective of this study was to investigate masticatory jaw movement among different forms of cross-bite. One hundred and one adults were recruited in this study: 27 had unilateral first molar cross-bite (MC group); 28, unilateral pre-molar cross-bite (PC group); 23, anterior cross-bite (AC group); and 23, normal occlusion (control group). Masticatory jaw movement of the lower incisor point was recorded with six degrees of freedom jaw-tracking system during unilateral mastication. Our results showed that the reverse chewing ratio during deliberate unilateral mastication was significantly larger in the MC group than in the PA (P < 0.001), AC (P < 0.001) and control (P < 0.001) groups. These findings suggest that compared to the anterior or pre-molar cross-bite, the first molar cross-bite is more closely associated with a higher prevalence of a reverse chewing cycle. © 2014 John Wiley & Sons Ltd.
Multiple objects tracking with HOGs matching in circular windows
NASA Astrophysics Data System (ADS)
Miramontes-Jaramillo, Daniel; Kober, Vitaly; Díaz-Ramírez, Víctor H.
2014-09-01
In recent years tracking applications with development of new technologies like smart TVs, Kinect, Google Glass and Oculus Rift become very important. When tracking uses a matching algorithm, a good prediction algorithm is required to reduce the search area for each object to be tracked as well as processing time. In this work, we analyze the performance of different tracking algorithms based on prediction and matching for a real-time tracking multiple objects. The used matching algorithm utilizes histograms of oriented gradients. It carries out matching in circular windows, and possesses rotation invariance and tolerance to viewpoint and scale changes. The proposed algorithm is implemented in a personal computer with GPU, and its performance is analyzed in terms of processing time in real scenarios. Such implementation takes advantage of current technologies and helps to process video sequences in real-time for tracking several objects at the same time.
Under sleeper pads in switches & crossings
NASA Astrophysics Data System (ADS)
Plasek, Otto; Hruzikova, Miroslava
2017-09-01
Under sleeper pads (USPs) have been installed in the Czech railway lines since 2007 into two trial sections in switches and crossings and in a trial section with the aim to reduce rail pitch corrugation. The basic motivation for the construction of the trial track sections in turnouts was an evaluation of USPs’ influence on improvement of track quality as a consequence of ballast bed protection against extreme stress. The paper comprises experience of USPs installation in the Czech Republic in the two trial sections with switches and crossings built in 2007 and 2014. The paper particularly provides an information about USPs applications focusing on the track settlement received by an evaluation of data from the geodetic surveying by precise levelling. Some positive influence of under sleeper pads on the track quality is observed.
Chen, Chi-Hsin; Gershkoff-Stowe, Lisa; Wu, Chih-Yi; Cheung, Hintat; Yu, Chen
2017-08-01
Two experiments were conducted to examine adult learners' ability to extract multiple statistics in simultaneously presented visual and auditory input. Experiment 1 used a cross-situational learning paradigm to test whether English speakers were able to use co-occurrences to learn word-to-object mappings and concurrently form object categories based on the commonalities across training stimuli. Experiment 2 replicated the first experiment and further examined whether speakers of Mandarin, a language in which final syllables of object names are more predictive of category membership than English, were able to learn words and form object categories when trained with the same type of structures. The results indicate that both groups of learners successfully extracted multiple levels of co-occurrence and used them to learn words and object categories simultaneously. However, marked individual differences in performance were also found, suggesting possible interference and competition in processing the two concurrent streams of regularities. Copyright © 2016 Cognitive Science Society, Inc.
Multiple Object Tracking Reveals Object-Based Grouping Interference in Children with ASD
ERIC Educational Resources Information Center
Van der Hallen, Ruth; Evers, Kris; de-Wit, Lee; Steyaert, Jean; Noens, Ilse; Wagemans, Johan
2018-01-01
The multiple object tracking (MOT) paradigm has proven its value in targeting a number of aspects of visual cognition. This study used MOT to investigate the effect of object-based grouping, both in children with and without autism spectrum disorder (ASD). A modified MOT task was administered to both groups, who had to track and distinguish four…
Fuentes, Silvia; Carrasco, Javier; Hatto, Abigail; Navarro, Juan; Armario, Antonio; Monsonet, Manel; Ortiz, Jordi; Nadal, Roser
2018-01-01
Early life stress (ELS) induces long-term effects in later functioning and interacts with further exposure to other stressors in adulthood to shape our responsiveness to reward-related cues. The attribution of incentive salience to food-related cues may be modulated by previous and current exposures to stressors in a sex-dependent manner. We hypothesized from human data that exposure to a traumatic (severe) adult stressor will decrease the attribution of incentive salience to reward-associated cues, especially in females, because these effects are modulated by previous ELS. To study these factors in Long-Evans rats, we used as an ELS model of restriction of nesting material and concurrently evaluated maternal care. In adulthood, the offspring of both sexes were exposed to acute immobilization (IMO), and several days after, a Pavlovian conditioning procedure was used to assess the incentive salience of food-related cues. Some rats developed more attraction to the cue predictive of reward (sign-tracking) and others were attracted to the location of the reward itself, the food-magazine (goal-tracking). Several dopaminergic markers were evaluated by in situ hybridization. The results showed that ELS increased maternal care and decreased body weight gain (only in females). Regarding incentive salience, in absolute control animals, females presented slightly greater sign-tracking behavior than males. Non-ELS male rats exposed to IMO showed a bias towards goal-tracking, whereas in females, IMO produced a bias towards sign-tracking. Animals of both sexes not exposed to IMO displayed an intermediate phenotype. ELS in IMO-treated females was able to reduce sign-tracking and decrease tyrosine hydroxylase expression in the ventral tegmental area and dopamine D1 receptor expression in the accumbens shell. Although the predicted greater decrease in females in sign-tracking after IMO exposure was not corroborated by the data, the results highlight the idea that sex is an important factor in the study of the long-term impact of early and adult stressors.
Fuentes, Silvia; Carrasco, Javier; Hatto, Abigail; Navarro, Juan; Armario, Antonio; Monsonet, Manel; Ortiz, Jordi
2018-01-01
Early life stress (ELS) induces long-term effects in later functioning and interacts with further exposure to other stressors in adulthood to shape our responsiveness to reward-related cues. The attribution of incentive salience to food-related cues may be modulated by previous and current exposures to stressors in a sex-dependent manner. We hypothesized from human data that exposure to a traumatic (severe) adult stressor will decrease the attribution of incentive salience to reward-associated cues, especially in females, because these effects are modulated by previous ELS. To study these factors in Long-Evans rats, we used as an ELS model of restriction of nesting material and concurrently evaluated maternal care. In adulthood, the offspring of both sexes were exposed to acute immobilization (IMO), and several days after, a Pavlovian conditioning procedure was used to assess the incentive salience of food-related cues. Some rats developed more attraction to the cue predictive of reward (sign-tracking) and others were attracted to the location of the reward itself, the food-magazine (goal-tracking). Several dopaminergic markers were evaluated by in situ hybridization. The results showed that ELS increased maternal care and decreased body weight gain (only in females). Regarding incentive salience, in absolute control animals, females presented slightly greater sign-tracking behavior than males. Non-ELS male rats exposed to IMO showed a bias towards goal-tracking, whereas in females, IMO produced a bias towards sign-tracking. Animals of both sexes not exposed to IMO displayed an intermediate phenotype. ELS in IMO-treated females was able to reduce sign-tracking and decrease tyrosine hydroxylase expression in the ventral tegmental area and dopamine D1 receptor expression in the accumbens shell. Although the predicted greater decrease in females in sign-tracking after IMO exposure was not corroborated by the data, the results highlight the idea that sex is an important factor in the study of the long-term impact of early and adult stressors. PMID:29324797
NASA Astrophysics Data System (ADS)
Li, X.; Torstensson, P. T.; Nielsen, J. C. O.
2017-12-01
Vertical dynamic vehicle-track interaction in the through route of a railway crossing is simulated in the time domain based on a Green's function approach for the track in combination with an implementation of Kalker's variational method to solve the non-Hertzian, and potentially multiple, wheel-rail contact. The track is described by a linear, three-dimensional and non-periodic finite element model of a railway turnout accounting for the variations in rail cross-sections and sleeper lengths, and including baseplates and resilient elements. To reduce calculation time due to the complexity of the track model, involving a large number of elements and degrees-of-freedom, a complex-valued modal superposition with a truncated mode set is applied before the impulse response functions are calculated at various positions along the crossing panel. The variation in three-dimensional contact geometry of the crossing and wheel is described by linear surface elements. In each time step of the contact detection algorithm, the lateral position of the wheelset centre is prescribed but the contact positions on wheel and rail are not, allowing for an accurate prediction of the wheel transition between wing rail and crossing rail. The method is demonstrated by calculating the wheel-rail impact load and contact stress distribution for a nominal S1002 wheel profile passing over a nominal crossing geometry. A parameter study is performed to determine the influence of vehicle speed, rail pad stiffness, lateral wheelset position and wheel profile on the impact load generated at the crossing. It is shown that the magnitude of the impact load is more influenced the wheel-rail contact geometry than by the selection of rail pad stiffness.
Combining user logging with eye tracking for interactive and dynamic applications.
Ooms, Kristien; Coltekin, Arzu; De Maeyer, Philippe; Dupont, Lien; Fabrikant, Sara; Incoul, Annelies; Kuhn, Matthias; Slabbinck, Hendrik; Vansteenkiste, Pieter; Van der Haegen, Lise
2015-12-01
User evaluations of interactive and dynamic applications face various challenges related to the active nature of these displays. For example, users can often zoom and pan on digital products, and these interactions cause changes in the extent and/or level of detail of the stimulus. Therefore, in eye tracking studies, when a user's gaze is at a particular screen position (gaze position) over a period of time, the information contained in this particular position may have changed. Such digital activities are commonplace in modern life, yet it has been difficult to automatically compare the changing information at the viewed position, especially across many participants. Existing solutions typically involve tedious and time-consuming manual work. In this article, we propose a methodology that can overcome this problem. By combining eye tracking with user logging (mouse and keyboard actions) with cartographic products, we are able to accurately reference screen coordinates to geographic coordinates. This referencing approach allows researchers to know which geographic object (location or attribute) corresponds to the gaze coordinates at all times. We tested the proposed approach through two case studies, and discuss the advantages and disadvantages of the applied methodology. Furthermore, the applicability of the proposed approach is discussed with respect to other fields of research that use eye tracking-namely, marketing, sports and movement sciences, and experimental psychology. From these case studies and discussions, we conclude that combining eye tracking and user-logging data is an essential step forward in efficiently studying user behavior with interactive and static stimuli in multiple research fields.
Improved scheme for Cross-track Infrared Sounder geolocation assessment and optimization
NASA Astrophysics Data System (ADS)
Wang, Likun; Zhang, Bin; Tremblay, Denis; Han, Yong
2017-01-01
An improved scheme for Cross-track Infrared Sounder (CrIS) geolocation assessment for all scan angles (from -48.5° to 48.5°) is developed in this study. The method uses spatially collocated radiance measurements from the Visible Infrared Imaging Radiometer Suite (VIIRS) image band I5 to evaluate the geolocation performance of the CrIS Sensor Data Records (SDR) by taking advantage of its high spatial resolution (375 m at nadir) and accurate geolocation. The basic idea is to perturb CrIS line-of-sight vectors along the in-track and cross-track directions to find a position where CrIS and VIIRS data matches more closely. The perturbation angles at this best matched position are then used to evaluate the CrIS geolocation accuracy. More importantly, the new method is capable of performing postlaunch on-orbit geometric calibration by optimizing mapping angle parameters based on the assessment results and thus can be further extended to the following CrIS sensors on new satellites. Finally, the proposed method is employed to evaluate the CrIS geolocation accuracy on current Suomi National Polar-orbiting Partnership satellite. The error characteristics are revealed along the scan positions in the in-track and cross-track directions. It is found that there are relatively large errors ( 4 km) in the cross-track direction close to the end of scan positions. With newly updated mapping angles, the geolocation accuracy is greatly improved for all scan positions (less than 0.3 km). This makes CrIS and VIIRS spatially align together and thus benefits the application that needs combination of CrIS and VIIRS measurements and products.
Small Orbital Stereo Tracking Camera Technology Development
NASA Technical Reports Server (NTRS)
Bryan, Tom; MacLeod, Todd; Gagliano, Larry
2017-01-01
Any exploration vehicle assembled or Spacecraft placed in LEO or GTO must pass through this debris cloud and survive. Large cross section, low thrust vehicles will spend more time spiraling out through the cloud and will suffer more impacts.Better knowledge of small debris will improve survival odds. Current estimated Density of debris at various orbital attitudes with notation of recent collisions and resulting spikes. Orbital Debris Tracking and Characterization has now been added to NASA Office of Chief Technologists Technology Development Roadmap in Technology Area 5 (TA5.7)[Orbital Debris Tracking and Characterization] and is a technical gap in the current National Space Situational Awareness necessary to safeguard orbital assets and crews due to the risk of Orbital Debris damage to ISS Exploration vehicles. The Problem: Traditional orbital trackers looking for small, dim orbital derelicts and debris typically will stare at the stars and let any reflected light off the debris integrate in the imager for seconds, thus creating a streak across the image. The Solution: The Small Tracker will see Stars and other celestial objects rise through its Field of View (FOV) at the rotational rate of its orbit, but the glint off of orbital objects will move through the FOV at different rates and directions. Debris on a head-on collision course (or close) will stay in the FOV at 14 Km per sec. The Small Tracker can track at 60 frames per sec allowing up to 30 fixes before a near-miss pass. A Stereo pair of Small Trackers can provide range data within 5-7 Km for better orbit measurements.
Rodríguez-Canosa, Gonzalo; Giner, Jaime del Cerro; Barrientos, Antonio
2014-01-01
The detection and tracking of mobile objects (DATMO) is progressively gaining importance for security and surveillance applications. This article proposes a set of new algorithms and procedures for detecting and tracking mobile objects by robots that work collaboratively as part of a multirobot system. These surveillance algorithms are conceived of to work with data provided by long distance range sensors and are intended for highly reliable object detection in wide outdoor environments. Contrary to most common approaches, in which detection and tracking are done by an integrated procedure, the approach proposed here relies on a modular structure, in which detection and tracking are carried out independently, and the latter might accept input data from different detection algorithms. Two movement detection algorithms have been developed for the detection of dynamic objects by using both static and/or mobile robots. The solution to the overall problem is based on the use of a Kalman filter to predict the next state of each tracked object. Additionally, new tracking algorithms capable of combining dynamic objects lists coming from either one or various sources complete the solution. The complementary performance of the separated modular structure for detection and identification is evaluated and, finally, a selection of test examples discussed. PMID:24526305
Brockhoff, Alisa; Huff, Markus
2016-10-01
Multiple object tracking (MOT) plays a fundamental role in processing and interpreting dynamic environments. Regarding the type of information utilized by the observer, recent studies reported evidence for the use of object features in an automatic, low- level manner. By introducing a novel paradigm that allowed us to combine tracking with a noninterfering top-down task, we tested whether a voluntary component can regulate the deployment of attention to task-relevant features in a selective manner. In four experiments we found conclusive evidence for a task-driven selection mechanism that guides attention during tracking: The observers were able to ignore or prioritize distinct objects. They marked the distinct (cued) object (target/distractor) more or less often than other objects of the same type (targets /distractors)-but only when they had received an identification task that required them to actively process object features (cues) during tracking. These effects are discussed with regard to existing theoretical approaches to attentive tracking, gaze-cue usability as well as attentional readiness, a term that originally stems from research on attention capture and visual search. Our findings indicate that existing theories of MOT need to be adjusted to allow for flexible top-down, voluntary processing during tracking.
Effects of railway track design on the expected degradation: Parametric study on energy dissipation
NASA Astrophysics Data System (ADS)
Sadri, Mehran; Steenbergen, Michaël
2018-04-01
This paper studies the effect of railway track design parameters on the expected long-term degradation of track geometry. The study assumes a geometrically perfect and straight track along with spatial invariability, except for the presence of discrete sleepers. A frequency-domain two-layer model is used of a discretely supported rail coupled with a moving unsprung mass. The susceptibility of the track to degradation is objectively quantified by calculating the mechanical energy dissipated in the substructure under a moving train axle for variations of different track parameters. Results show that, apart from the operational train speed, the ballast/substructure stiffness is the most significant parameter influencing energy dissipation. Generally, the degradation increases with the train speed and with softer substructures. However, stiff subgrades appear more sensitive to particular train velocities, in a regime which is mostly relevant for conventional trains (100-200 km/h) and less for high-speed operation, where a stiff subgrade is always favorable and can reduce the sensitivity to degradation substantially, with roughly a factor up to 7. Also railpad stiffness, sleeper distance and rail cross-sectional properties are found to have considerable effect, with higher expected degradation rates for increasing railpad stiffness, increasing sleeper distance and decreasing rail profile bending stiffness. Unsprung vehicle mass and sleeper mass have no significant influence, however, only against the background of the assumption of an idealized (invariant and straight) track. Apart from dissipated mechanical energy, the suitability of the dynamic track stiffness is explored as an engineering parameter to assess the sensitivity to degradation. It is found that this quantity is inappropriate to assess the design of an idealized track.
Attribution of Mild Cognitive Impairment Etiology in Patients and Their Care-Partners
Rodakowski, Juleen; Schulz, Richard; Gentry, Amanda; Garand, Linda; Lingler, Jennifer Hagerty
2013-01-01
Objective This study examined the attribution of MCI etiology assigned by individuals with MCI and their care-partners, and the extent to which the dyads agreed on the attribution of MCI etiology. Methods We conducted secondary analyses of cross-sectional data from a cohort of individuals with MCI (n=60) and their care-partners (n=60). The mean age of the individuals with MCI was 71.0±9.4 and of care-partners 64.2±11.0 years. The primary outcome was attribution assigned to memory deficits on the Illness Perception Questionnaire. We categorized the attribution of MCI etiology as either potentially controllable or uncontrollable factors. We described the distribution of MCI etiology with descriptive and contingency tables. We determined the odds of a patient or care-partner choosing one type of MCI etiology over another. Results Although individuals with MCI and their care-partners most frequently attributed MCI to uncontrollable factors (81.7% and 61.0%, respectively), care-partners were 28.41 [95% CI, 1.26 to 645.48] times more likely to attribute MCI etiology to potentially controllable factors than individuals with MCI. No significant associations between demographic factors and attribution of MCI etiology were found for the individuals with MCI or the care-partners. Conclusion Findings demonstrated that members of the dyad attributed MCI etiology to different causes. Attributions of MCI etiology should be explored by professionals to clarify misconceptions and potentially improve subsequent voluntary actions intended to assist oneself or others. PMID:24123240
Nonstationary EO/IR Clutter Suppression and Dim Object Tracking
NASA Astrophysics Data System (ADS)
Tartakovsky, A.; Brown, A.; Brown, J.
2010-09-01
We develop and evaluate the performance of advanced algorithms which provide significantly improved capabilities for automated detection and tracking of ballistic and flying dim objects in the presence of highly structured intense clutter. Applications include ballistic missile early warning, midcourse tracking, trajectory prediction, and resident space object detection and tracking. The set of algorithms include, in particular, adaptive spatiotemporal clutter estimation-suppression and nonlinear filtering-based multiple-object track-before-detect. These algorithms are suitable for integration into geostationary, highly elliptical, or low earth orbit scanning or staring sensor suites, and are based on data-driven processing that adapts to real-world clutter backgrounds, including celestial, earth limb, or terrestrial clutter. In many scenarios of interest, e.g., for highly elliptic and, especially, low earth orbits, the resulting clutter is highly nonstationary, providing a significant challenge for clutter suppression to or below sensor noise levels, which is essential for dim object detection and tracking. We demonstrate the success of the developed algorithms using semi-synthetic and real data. In particular, our algorithms are shown to be capable of detecting and tracking point objects with signal-to-clutter levels down to 1/1000 and signal-to-noise levels down to 1/4.
Fast Legendre moment computation for template matching
NASA Astrophysics Data System (ADS)
Li, Bing C.
2017-05-01
Normalized cross correlation (NCC) based template matching is insensitive to intensity changes and it has many applications in image processing, object detection, video tracking and pattern recognition. However, normalized cross correlation implementation is computationally expensive since it involves both correlation computation and normalization implementation. In this paper, we propose Legendre moment approach for fast normalized cross correlation implementation and show that the computational cost of this proposed approach is independent of template mask sizes which is significantly faster than traditional mask size dependent approaches, especially for large mask templates. Legendre polynomials have been widely used in solving Laplace equation in electrodynamics in spherical coordinate systems, and solving Schrodinger equation in quantum mechanics. In this paper, we extend Legendre polynomials from physics to computer vision and pattern recognition fields, and demonstrate that Legendre polynomials can help to reduce the computational cost of NCC based template matching significantly.
Alfred binet and the concept of heterogeneous orders.
Michell, Joel
2012-01-01
In a comment, hitherto unremarked upon, Alfred Binet, well known for constructing the first intelligence scale, claimed that his scale did not measure intelligence, but only enabled classification with respect to a hierarchy of intellectual qualities. Attempting to understand the reasoning behind this comment leads to an historical excursion, beginning with the ancient mathematician, Euclid and ending with the modern French philosopher, Henri Bergson. As Euclid explained (Heath, 1908), magnitudes constituting a given quantitative attribute are all of the same kind (i.e., homogeneous), but his criterion covered only extensive magnitudes. Duns Scotus (Cross, 1998) included intensive magnitudes by considering differences, which raised the possibility (later considered by Sutherland, 2004) of ordered attributes with heterogeneous differences between degrees ("heterogeneous orders"). Of necessity, such attributes are non-measurable. Subsequently, this became a basis for the "quantity objection" to psychological measurement, as developed first by Tannery (1875a,b) and then by Bergson (1889). It follows that for attributes investigated in science, there are three structural possibilities: (1) classificatory attributes (with heterogeneous differences between categories); (2) heterogeneous orders (with heterogeneous differences between degrees); and (3) quantitative attributes (with thoroughly homogeneous differences between magnitudes). Measurement is possible only with attributes of kind (3) and, as far as we know, psychological attributes are exclusively of kinds (1) or (2). However, contrary to the known facts, psychometricians, for their own special reasons insist that test scores provide measurements.
A visual tracking method based on deep learning without online model updating
NASA Astrophysics Data System (ADS)
Tang, Cong; Wang, Yicheng; Feng, Yunsong; Zheng, Chao; Jin, Wei
2018-02-01
The paper proposes a visual tracking method based on deep learning without online model updating. In consideration of the advantages of deep learning in feature representation, deep model SSD (Single Shot Multibox Detector) is used as the object extractor in the tracking model. Simultaneously, the color histogram feature and HOG (Histogram of Oriented Gradient) feature are combined to select the tracking object. In the process of tracking, multi-scale object searching map is built to improve the detection performance of deep detection model and the tracking efficiency. In the experiment of eight respective tracking video sequences in the baseline dataset, compared with six state-of-the-art methods, the method in the paper has better robustness in the tracking challenging factors, such as deformation, scale variation, rotation variation, illumination variation, and background clutters, moreover, its general performance is better than other six tracking methods.
Störmer, Viola S; Li, Shu-Chen; Heekeren, Hauke R; Lindenberger, Ulman
2011-02-01
The ability to attend to multiple objects that move in the visual field is important for many aspects of daily functioning. The attentional capacity for such dynamic tracking, however, is highly limited and undergoes age-related decline. Several aspects of the tracking process can influence performance. Here, we investigated effects of feature-based interference from distractor objects that appear in unattended regions of the visual field with a hemifield-tracking task. Younger and older participants performed an attentional tracking task in one hemifield while distractor objects were concurrently presented in the unattended hemifield. Feature similarity between objects in the attended and unattended hemifields as well as motion speed and the number of to-be-tracked objects were parametrically manipulated. The results show that increasing feature overlap leads to greater interference from the unattended visual field. This effect of feature-based interference was only present in the slow speed condition, indicating that the interference is mainly modulated by perceptual demands. High-performing older adults showed a similar interference effect as younger adults, whereas low-performing adults showed poor tracking performance overall.
Robust Pedestrian Tracking and Recognition from FLIR Video: A Unified Approach via Sparse Coding
Li, Xin; Guo, Rui; Chen, Chao
2014-01-01
Sparse coding is an emerging method that has been successfully applied to both robust object tracking and recognition in the vision literature. In this paper, we propose to explore a sparse coding-based approach toward joint object tracking-and-recognition and explore its potential in the analysis of forward-looking infrared (FLIR) video to support nighttime machine vision systems. A key technical contribution of this work is to unify existing sparse coding-based approaches toward tracking and recognition under the same framework, so that they can benefit from each other in a closed-loop. On the one hand, tracking the same object through temporal frames allows us to achieve improved recognition performance through dynamical updating of template/dictionary and combining multiple recognition results; on the other hand, the recognition of individual objects facilitates the tracking of multiple objects (i.e., walking pedestrians), especially in the presence of occlusion within a crowded environment. We report experimental results on both the CASIAPedestrian Database and our own collected FLIR video database to demonstrate the effectiveness of the proposed joint tracking-and-recognition approach. PMID:24961216
DOT National Transportation Integrated Search
2011-03-01
"NHTSA selected the vehicle footprint (the measure of a vehicles wheelbase multiplied by its average track width) as the attribute upon which to base the CAFE standards for model year 2012-2016 passenger cars and light trucks. These standards are ...
Isolating the Incentive Salience of Reward-Associated Stimuli: Value, Choice, and Persistence
ERIC Educational Resources Information Center
Beckmann, Joshua S.; Chow, Jonathan J.
2015-01-01
Sign- and goal-tracking are differentially associated with drug abuse-related behavior. Recently, it has been hypothesized that sign- and goal-tracking behavior are mediated by different neurobehavioral valuation systems, including differential incentive salience attribution. Herein, we used different conditioned stimuli to preferentially elicit…
Platt, Brian F; Suarez, Celina A; Boss, Stephen K; Williamson, Malcolm; Cothren, Jackson; Kvamme, Jo Ann C
2018-01-01
LIDAR-based analyses of the first theropod dinosaur trackways known from the state of Arkansas, USA are reported. The trackways were found on a limestone bedding plane in the Albian De Queen Formation in an active gypsum quarry. Because limited access precluded thorough field study, fieldwork focused on preserving the entire site digitally with ground-based LIDAR, and detailed measurements were later taken digitally from point cloud data. The site contains eight tridactyl trackways associated with sauropod trackways and numerous isolated tracks. Although there appear to be two different tridactyl morphotypes, we show that the tracks are all likely from a single species of trackmaker. We apply a simple method of estimating substrate consistency by comparing the differences between true track dimensions and apparent track dimensions. The tridactyl tracks at the southern end of the site are preserved with significantly greater differences in true vs. apparent dimensions and are shallower than the rest of the tridactyl tracks at the site, which we interpret as the result of outward expansion of the soft tissues of the foot upon contact with a firm substrate. We interpret the firm substrate as having high bulk density and high shear strength, which also explain associated manus-only sauropod tracks. We show that the tridactyl tracks are likely from theropod trackmakers and that footprint lengths, trackway paces, stride lengths, and pace angulations of the De Queen trackways are statistically indistinguishable from equivalent measurements of theropod trackways in the Glen Rose Formation. The Glen Rose tracks are attributed to the large-bodied theropod, Acrocanthosaurus and we likewise attribute the De Queen tracks to Acrocanthosaurus, which is known from skeletal remains in temporally equivalent units and from the mine itself.
Stakeholder identification of advanced technology opportunities at international ports of entry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parker, S.K.; Icerman, L.
As part of the Advanced Technologies for International and Intermodal Ports of Entry (ATIPE) Project, a diverse group of stakeholders was engaged to help identify problems experienced at inland international border crossings, particularly those at the US-Mexican border. The fundamental issue at international ports of entry is reducing transit time through the required documentation and inspection processes. Examples of other issues or problems, typically manifested as time delays at border crossings, repeatedly mentioned by stakeholders include: (1) lack of document standardization; (2) failure to standardize inspection processes; (3) inadequate information and communications systems; (4) manual fee and tariff collection; (5)more » inconsistency of processes and procedures; and (6) suboptimal cooperation among governmental agencies. Most of these issues can be addressed to some extent by the development of advanced technologies with the objective of allowing ports of entry to become more efficient while being more effective. Three categories of technologies were unambiguously of high priority to port of entry stakeholders: (1) automated documentation; (2) systems integration; and (3) vehicle and cargo tracking. Together, these technologies represent many of the technical components necessary for pre-clearance of freight approaching international ports of entry. Integration of vehicle and cargo tracking systems with port of entry information and communications systems, as well as existing industry legacy systems, should further enable border crossings to be accomplished consistently with optimal processing times.« less
The research on the mean shift algorithm for target tracking
NASA Astrophysics Data System (ADS)
CAO, Honghong
2017-06-01
The traditional mean shift algorithm for target tracking is effective and high real-time, but there still are some shortcomings. The traditional mean shift algorithm is easy to fall into local optimum in the tracking process, the effectiveness of the method is weak when the object is moving fast. And the size of the tracking window never changes, the method will fail when the size of the moving object changes, as a result, we come up with a new method. We use particle swarm optimization algorithm to optimize the mean shift algorithm for target tracking, Meanwhile, SIFT (scale-invariant feature transform) and affine transformation make the size of tracking window adaptive. At last, we evaluate the method by comparing experiments. Experimental result indicates that the proposed method can effectively track the object and the size of the tracking window changes.
LANDSAT-4 MSS Geometric Correction: Methods and Results
NASA Technical Reports Server (NTRS)
Brooks, J.; Kimmer, E.; Su, J.
1984-01-01
An automated image registration system such as that developed for LANDSAT-4 can produce all of the information needed to verify and calibrate the software and to evaluate system performance. The on-line MSS archive generation process which upgrades systematic correction data to geodetic correction data is described as well as the control point library build subsystem which generates control point chips and support data for on-line upgrade of correction data. The system performance was evaluated for both temporal and geodetic registration. For temporal registration, 90% errors were computed to be .36 IFOV (instantaneous field of view) = 82.7 meters) cross track, and .29 IFOV along track. Also, for actual production runs monitored, the 90% errors were .29 IFOV cross track and .25 IFOV along track. The system specification is .3 IFOV, 90% of the time, both cross and along track. For geodetic registration performance, the model bias was measured by designating control points in the geodetically corrected imagery.
Ego-Motion and Tracking for Continuous Object Learning: A Brief Survey
2017-09-01
ARL-TR-8167• SEP 2017 US Army Research Laboratory Ego-motion and Tracking for ContinuousObject Learning: A Brief Survey by Jason Owens and Philip...SEP 2017 US Army Research Laboratory Ego-motion and Tracking for ContinuousObject Learning: A Brief Survey by Jason Owens and Philip OsteenVehicle...
Locator-Checker-Scaler Object Tracking Using Spatially Ordered and Weighted Patch Descriptor.
Kim, Han-Ul; Kim, Chang-Su
2017-08-01
In this paper, we propose a simple yet effective object descriptor and a novel tracking algorithm to track a target object accurately. For the object description, we divide the bounding box of a target object into multiple patches and describe them with color and gradient histograms. Then, we determine the foreground weight of each patch to alleviate the impacts of background information in the bounding box. To this end, we perform random walk with restart (RWR) simulation. We then concatenate the weighted patch descriptors to yield the spatially ordered and weighted patch (SOWP) descriptor. For the object tracking, we incorporate the proposed SOWP descriptor into a novel tracking algorithm, which has three components: locator, checker, and scaler (LCS). The locator and the scaler estimate the center location and the size of a target, respectively. The checker determines whether it is safe to adjust the target scale in a current frame. These three components cooperate with one another to achieve robust tracking. Experimental results demonstrate that the proposed LCS tracker achieves excellent performance on recent benchmarks.
3D noise-resistant segmentation and tracking of unknown and occluded objects using integral imaging
NASA Astrophysics Data System (ADS)
Aloni, Doron; Jung, Jae-Hyun; Yitzhaky, Yitzhak
2017-10-01
Three dimensional (3D) object segmentation and tracking can be useful in various computer vision applications, such as: object surveillance for security uses, robot navigation, etc. We present a method for 3D multiple-object tracking using computational integral imaging, based on accurate 3D object segmentation. The method does not employ object detection by motion analysis in a video as conventionally performed (such as background subtraction or block matching). This means that the movement properties do not significantly affect the detection quality. The object detection is performed by analyzing static 3D image data obtained through computational integral imaging With regard to previous works that used integral imaging data in such a scenario, the proposed method performs the 3D tracking of objects without prior information about the objects in the scene, and it is found efficient under severe noise conditions.
49 CFR 236.53 - Track circuit feed at grade crossing.
Code of Federal Regulations, 2010 CFR
2010-10-01
... an electric railroad where foreign current is present, the electric energy for noncoded direct... 49 Transportation 4 2010-10-01 2010-10-01 false Track circuit feed at grade crossing. 236.53 Section 236.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...
Rebueno, Ma Carina D R; Tiongco, Dyan Dee D; Macindo, John Rey B
2017-02-01
Clinical competence remains an issue in nursing and has received greater emphasis than academic competence. Although skill enhancement programs are recommended and beneficial, there is limited evidence on its influence on the clinical competence of pre-graduate nursing students. This study explored the attributes of a skills enhancement program that affect the perceived clinical competence of pre-graduate nursing students. A cross-sectional study was conducted in a private higher education institution in the Philippines from April to May 2016. A total of 245 pre-graduate nursing students participated and completed a three-part survey composed of the respondent's robotfoto, the Skills Enhancement Program Questionnaire, and the Clinical Competence Questionnaire. Factor analysis explicated the attributes of the skills enhancement program while structural equation modeling and path analysis analyzed the variables' relationship. Findings showed that a skills enhancement program has 4 attributes: supportive clinical instructor, comprehensive orientation, formative goals and objectives, and conducive learning environment. Although all attributes of the program positively affected clinical competence, a supportive clinical instructor had the strongest influence on all clinical competency dimensions. A skills enhancement program that has a supportive clinical instructor, comprehensive orientation, formative goals and objectives, and conducive learning environment facilitates clinical competency development among pre-graduate nursing students. This knowledge provides momentum for nursing educators to review and refine their skills and the existing design of their skills enhancement program to further develop clinical competency among pre-graduate nursing students. Copyright © 2016 Elsevier Ltd. All rights reserved.
Obstacle penetrating dynamic radar imaging system
Romero, Carlos E [Livermore, CA; Zumstein, James E [Livermore, CA; Chang, John T [Danville, CA; Leach, Jr Richard R. [Castro Valley, CA
2006-12-12
An obstacle penetrating dynamic radar imaging system for the detection, tracking, and imaging of an individual, animal, or object comprising a multiplicity of low power ultra wideband radar units that produce a set of return radar signals from the individual, animal, or object, and a processing system for said set of return radar signals for detection, tracking, and imaging of the individual, animal, or object. The system provides a radar video system for detecting and tracking an individual, animal, or object by producing a set of return radar signals from the individual, animal, or object with a multiplicity of low power ultra wideband radar units, and processing said set of return radar signals for detecting and tracking of the individual, animal, or object.
Attention Modulates Spatial Precision in Multiple-Object Tracking.
Srivastava, Nisheeth; Vul, Ed
2016-01-01
We present a computational model of multiple-object tracking that makes trial-level predictions about the allocation of visual attention and the effect of this allocation on observers' ability to track multiple objects simultaneously. This model follows the intuition that increased attention to a location increases the spatial resolution of its internal representation. Using a combination of empirical and computational experiments, we demonstrate the existence of a tight coupling between cognitive and perceptual resources in this task: Low-level tracking of objects generates bottom-up predictions of error likelihood, and high-level attention allocation selectively reduces error probabilities in attended locations while increasing it at non-attended locations. Whereas earlier models of multiple-object tracking have predicted the big picture relationship between stimulus complexity and response accuracy, our approach makes accurate predictions of both the macro-scale effect of target number and velocity on tracking difficulty and micro-scale variations in difficulty across individual trials and targets arising from the idiosyncratic within-trial interactions of targets and distractors. Copyright © 2016 Cognitive Science Society, Inc.
Perceptual-Motor Attributes of Mentally Retarded Youth.
ERIC Educational Resources Information Center
Cratty, Bryant J.
To evaluate six perceptual-motor attributes of trainable and educable mentally retarded children, a battery of tests was constructed which included body perception, gross agility, balance, locomotor ability, throwing, and tracking; 83 retarded subjects provided reliability data, and their scores, with those of 120 additional subjects, provided…
Two-degrees-of-freedom piezo-driven fast steering mirror with cross-axis decoupling capability
NASA Astrophysics Data System (ADS)
Shao, Shubao; Tian, Zheng; Song, Siyang; Xu, Minglong
2018-05-01
Because mechanical cross coupling between its axes would lead to degradation of the scanning precision of a piezo-driven fast steering mirror (PFSM), a two-degrees-of-freedom (2-DoF) PFSM with a cross-axis decoupling capability, in which 2-DoF flexure hinges are used, is proposed in this work. The overall structure of the proposed PFSM is first introduced and then both static and dynamic models are established analytically; in addition, the decoupling mechanism is described in detail and the low dynamic cross coupling ratios that occur between the two DoFs are shown. Because of the decoupling property of the PFSM, the 2-DoF motion is treated as a combination of two independent one-degree-of-freedom (1-DoF) motions and two independent proportional-integral-derivative controllers are thus used separately in the control of the two DoFs. Based on this control strategy, experiments involving both 1-DoF trajectory tracking and 2-DoF trajectory tracking are implemented. The test results show that the proposed PFSM can achieve the tilt range of ±7 mrad for both axes with the low coupling ratios that are less than 2% (-34 dB), and the bandwidths of both axes are higher than 810 Hz; in addition, the maximal tracking full scale range errors for 1-DoF trajectory tracking and 2-DoF trajectory tracking are less than 0.2% and 1%, respectively, where the larger error of 2-DoF trajectory tracking is mainly caused by the remaining cross coupling between axes.
NASA Technical Reports Server (NTRS)
Wheeler, Mark M.
1998-01-01
This report documents the Applied Meteorology Unit's evaluation of the Cell Trends display as a tool for radar operators to use in their evaluation of storm cell strength. The objective of the evaluation is to assess the utility of the WSR-88D graphical Cell Trends display for local radar cell interpretation in support of the 45th Weather Squadron (45 WS), Spaceflight Meteorology Group (SMG), and National Weather Service (NWS) Melbourne (MLB) operational requirements. The analysis procedure was to identify each cell and track the maximum reflectivity, height of maximum reflectivity, storm top, storm base, hail and severe hail probability, cell-based Vertically Integrated Liquid (VIL) and core aspect ratio using WATADS Build 9.0 cell trends information. One problem noted in the analysis phase was that the Storm Cell Identification and Tracking (SCIT) algorithm had a difficult time tracking the small cells associated with the Florida weather regimes. The analysis indicated numerous occasions when a cell track would end or an existing cell would be give a new ID in the middle of its life cycle. This investigation has found that most cells, which produce hail or microburst events, have discernable Cell Trends signatures. Forecasters should monitor the PUP's Cell Trends display for cells that show rapid (1 scan) changes in both the heights of maximum reflectivity and cell-based VIEL. It is important to note that this a very limited data set (four case days). Fifty-two storm cells were analyzed during those four days. The above mentioned t=ds, increase in the two cell attributes for hail events and decrease in the two cell attributes for wind events were noted in most of the cells. The probability of detection was 88% for both events. The False Alarm Rate (FAR) was a 36% for hail events and a respectable 25% for microburst events. In addition the Heidke Skill Score (HSS) is 0.65 for hail events and 0.67 for microburst events. For random forecast the HSS is 0 and that a perfect score is 1.
Enhanced online convolutional neural networks for object tracking
NASA Astrophysics Data System (ADS)
Zhang, Dengzhuo; Gao, Yun; Zhou, Hao; Li, Tianwen
2018-04-01
In recent several years, object tracking based on convolution neural network has gained more and more attention. The initialization and update of convolution filters can directly affect the precision of object tracking effective. In this paper, a novel object tracking via an enhanced online convolution neural network without offline training is proposed, which initializes the convolution filters by a k-means++ algorithm and updates the filters by an error back-propagation. The comparative experiments of 7 trackers on 15 challenging sequences showed that our tracker can perform better than other trackers in terms of AUC and precision.
NASA Astrophysics Data System (ADS)
Tartakovsky, A.; Tong, M.; Brown, A. P.; Agh, C.
2013-09-01
We develop efficient spatiotemporal image processing algorithms for rejection of non-stationary clutter and tracking of multiple dim objects using non-linear track-before-detect methods. For clutter suppression, we include an innovative image alignment (registration) algorithm. The images are assumed to contain elements of the same scene, but taken at different angles, from different locations, and at different times, with substantial clutter non-stationarity. These challenges are typical for space-based and surface-based IR/EO moving sensors, e.g., highly elliptical orbit or low earth orbit scenarios. The algorithm assumes that the images are related via a planar homography, also known as the projective transformation. The parameters are estimated in an iterative manner, at each step adjusting the parameter vector so as to achieve improved alignment of the images. Operating in the parameter space rather than in the coordinate space is a new idea, which makes the algorithm more robust with respect to noise as well as to large inter-frame disturbances, while operating at real-time rates. For dim object tracking, we include new advancements to a particle non-linear filtering-based track-before-detect (TrbD) algorithm. The new TrbD algorithm includes both real-time full image search for resolved objects not yet in track and joint super-resolution and tracking of individual objects in closely spaced object (CSO) clusters. The real-time full image search provides near-optimal detection and tracking of multiple extremely dim, maneuvering objects/clusters. The super-resolution and tracking CSO TrbD algorithm provides efficient near-optimal estimation of the number of unresolved objects in a CSO cluster, as well as the locations, velocities, accelerations, and intensities of the individual objects. We demonstrate that the algorithm is able to accurately estimate the number of CSO objects and their locations when the initial uncertainty on the number of objects is large. We demonstrate performance of the TrbD algorithm both for satellite-based and surface-based EO/IR surveillance scenarios.
NASA Technical Reports Server (NTRS)
Gennery, D.; Cunningham, R.; Saund, E.; High, J.; Ruoff, C.
1981-01-01
The field of computer vision is surveyed and assessed, key research issues are identified, and possibilities for a future vision system are discussed. The problems of descriptions of two and three dimensional worlds are discussed. The representation of such features as texture, edges, curves, and corners are detailed. Recognition methods are described in which cross correlation coefficients are maximized or numerical values for a set of features are measured. Object tracking is discussed in terms of the robust matching algorithms that must be devised. Stereo vision, camera control and calibration, and the hardware and systems architecture are discussed.
NASA Astrophysics Data System (ADS)
Pålsson, Björn A.; Nielsen, Jens C. O.
2015-06-01
A model for simulation of dynamic interaction between a railway vehicle and a turnout (switch and crossing, S&C) is validated versus field measurements. In particular, the implementation and accuracy of viscously damped track models with different complexities are assessed. The validation data come from full-scale field measurements of dynamic track stiffness and wheel-rail contact forces in a demonstrator turnout that was installed as part of the INNOTRACK project with funding from the European Union Sixth Framework Programme. Vertical track stiffness at nominal wheel loads, in the frequency range up to 20 Hz, was measured using a rolling stiffness measurement vehicle (RSMV). Vertical and lateral wheel-rail contact forces were measured by an instrumented wheel set mounted in a freight car featuring Y25 bogies. The measurements were performed for traffic in both the through and diverging routes, and in the facing and trailing moves. The full set of test runs was repeated with different types of rail pad to investigate the influence of rail pad stiffness on track stiffness and contact forces. It is concluded that impact loads on the crossing can be reduced by using more resilient rail pads. To allow for vehicle dynamics simulations at low computational cost, the track models are discretised space-variant mass-spring-damper models that are moving with each wheel set of the vehicle model. Acceptable agreement between simulated and measured vertical contact forces at the crossing can be obtained when the standard GENSYS track model is extended with one ballast/subgrade mass under each rail. This model can be tuned to capture the large phase delay in dynamic track stiffness at low frequencies, as measured by the RSMV, while remaining sufficiently resilient at higher frequencies.
Code of Federal Regulations, 2012 CFR
2012-04-01
...: Active warning devices means those traffic control devices activated by the approach or presence of a... means a group of knowledgeable representatives of the parties of interest in a railroad-highway crossing or a group of crossings. Main line railroad track means a track of a principal line of a railroad...
Code of Federal Regulations, 2011 CFR
2011-04-01
...: Active warning devices means those traffic control devices activated by the approach or presence of a... means a group of knowledgeable representatives of the parties of interest in a railroad-highway crossing or a group of crossings. Main line railroad track means a track of a principal line of a railroad...
Code of Federal Regulations, 2010 CFR
2010-04-01
...: Active warning devices means those traffic control devices activated by the approach or presence of a... means a group of knowledgeable representatives of the parties of interest in a railroad-highway crossing or a group of crossings. Main line railroad track means a track of a principal line of a railroad...
Adaptive particle filter for robust visual tracking
NASA Astrophysics Data System (ADS)
Dai, Jianghua; Yu, Shengsheng; Sun, Weiping; Chen, Xiaoping; Xiang, Jinhai
2009-10-01
Object tracking plays a key role in the field of computer vision. Particle filter has been widely used for visual tracking under nonlinear and/or non-Gaussian circumstances. In particle filter, the state transition model for predicting the next location of tracked object assumes the object motion is invariable, which cannot well approximate the varying dynamics of the motion changes. In addition, the state estimate calculated by the mean of all the weighted particles is coarse or inaccurate due to various noise disturbances. Both these two factors may degrade tracking performance greatly. In this work, an adaptive particle filter (APF) with a velocity-updating based transition model (VTM) and an adaptive state estimate approach (ASEA) is proposed to improve object tracking. In APF, the motion velocity embedded into the state transition model is updated continuously by a recursive equation, and the state estimate is obtained adaptively according to the state posterior distribution. The experiment results show that the APF can increase the tracking accuracy and efficiency in complex environments.
The role of contraceptive attributes in women's contraceptive decision making.
Madden, Tessa; Secura, Gina M; Nease, Robert F; Politi, Mary C; Peipert, Jeffrey F
2015-07-01
Contraceptive methods have differing attributes. Women's preferences for these attributes may influence contraceptive decision making. Our objective was to identify women's contraceptive preferences among women initiating a new contraceptive method. We conducted a cross-sectional, self-administered survey of women's contraceptive preferences at the time of enrollment into the Contraceptive CHOICE Project. Participants were asked to rank the importance of 15 contraceptive attributes on a 3-point scale (1 = not at all important, 2 = somewhat important, and 3 = very important) and then to rank the 3 attributes that were the most important when choosing a contraceptive method. The survey also contained questions about prior contraceptive experience and barriers to contraceptive use. Information about demographic and reproductive characteristics was collected through the CHOICE Project baseline survey. There were 2590 women who completed the survey. Our sample was racially and socioeconomically diverse. Method attributes with the highest importance score (mean score [SD]) were effectiveness (2.97 [0.18]), safety (2.96 [0.22]), affordability (2.61 [0.61]), whether the method is long lasting (2.58 [0.61]), and whether the method is "forgettable" (2.54 [0.66]). The attributes most likely to be ranked by respondents among the top 3 attributes included effectiveness (84.2%), safety (67.8%), and side effects of the method (44.6%). Multiple contraceptive attributes influence decision making and no single attribute drives most women's decisions. Tailoring communication and helping women make complex tradeoffs between attributes can better support their contraceptive decisions and may assist them in making value-consistent choices. This process could improve continuation and satisfaction. Copyright © 2015 Elsevier Inc. All rights reserved.
Attribute and topology based change detection in a constellation of previously detected objects
Paglieroni, David W.; Beer, Reginald N.
2016-01-19
A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.
Memory-Based Multiagent Coevolution Modeling for Robust Moving Object Tracking
Wang, Yanjiang; Qi, Yujuan; Li, Yongping
2013-01-01
The three-stage human brain memory model is incorporated into a multiagent coevolutionary process for finding the best match of the appearance of an object, and a memory-based multiagent coevolution algorithm for robust tracking the moving objects is presented in this paper. Each agent can remember, retrieve, or forget the appearance of the object through its own memory system by its own experience. A number of such memory-based agents are randomly distributed nearby the located object region and then mapped onto a 2D lattice-like environment for predicting the new location of the object by their coevolutionary behaviors, such as competition, recombination, and migration. Experimental results show that the proposed method can deal with large appearance changes and heavy occlusions when tracking a moving object. It can locate the correct object after the appearance changed or the occlusion recovered and outperforms the traditional particle filter-based tracking methods. PMID:23843739
Memory-based multiagent coevolution modeling for robust moving object tracking.
Wang, Yanjiang; Qi, Yujuan; Li, Yongping
2013-01-01
The three-stage human brain memory model is incorporated into a multiagent coevolutionary process for finding the best match of the appearance of an object, and a memory-based multiagent coevolution algorithm for robust tracking the moving objects is presented in this paper. Each agent can remember, retrieve, or forget the appearance of the object through its own memory system by its own experience. A number of such memory-based agents are randomly distributed nearby the located object region and then mapped onto a 2D lattice-like environment for predicting the new location of the object by their coevolutionary behaviors, such as competition, recombination, and migration. Experimental results show that the proposed method can deal with large appearance changes and heavy occlusions when tracking a moving object. It can locate the correct object after the appearance changed or the occlusion recovered and outperforms the traditional particle filter-based tracking methods.
Enhancing cognition with video games: a multiple game training study.
Oei, Adam C; Patterson, Michael D
2013-01-01
Previous evidence points to a causal link between playing action video games and enhanced cognition and perception. However, benefits of playing other video games are under-investigated. We examined whether playing non-action games also improves cognition. Hence, we compared transfer effects of an action and other non-action types that required different cognitive demands. We instructed 5 groups of non-gamer participants to play one game each on a mobile device (iPhone/iPod Touch) for one hour a day/five days a week over four weeks (20 hours). Games included action, spatial memory, match-3, hidden- object, and an agent-based life simulation. Participants performed four behavioral tasks before and after video game training to assess for transfer effects. Tasks included an attentional blink task, a spatial memory and visual search dual task, a visual filter memory task to assess for multiple object tracking and cognitive control, as well as a complex verbal span task. Action game playing eliminated attentional blink and improved cognitive control and multiple-object tracking. Match-3, spatial memory and hidden object games improved visual search performance while the latter two also improved spatial working memory. Complex verbal span improved after match-3 and action game training. Cognitive improvements were not limited to action game training alone and different games enhanced different aspects of cognition. We conclude that training specific cognitive abilities frequently in a video game improves performance in tasks that share common underlying demands. Overall, these results suggest that many video game-related cognitive improvements may not be due to training of general broad cognitive systems such as executive attentional control, but instead due to frequent utilization of specific cognitive processes during game play. Thus, many video game training related improvements to cognition may be attributed to near-transfer effects.
An experimental comparison of online object-tracking algorithms
NASA Astrophysics Data System (ADS)
Wang, Qing; Chen, Feng; Xu, Wenli; Yang, Ming-Hsuan
2011-09-01
This paper reviews and evaluates several state-of-the-art online object tracking algorithms. Notwithstanding decades of efforts, object tracking remains a challenging problem due to factors such as illumination, pose, scale, deformation, motion blur, noise, and occlusion. To account for appearance change, most recent tracking algorithms focus on robust object representations and effective state prediction. In this paper, we analyze the components of each tracking method and identify their key roles in dealing with specific challenges, thereby shedding light on how to choose and design algorithms for different situations. We compare state-of-the-art online tracking methods including the IVT,1 VRT,2 FragT,3 BoostT,4 SemiT,5 BeSemiT,6 L1T,7 MILT,8 VTD9 and TLD10 algorithms on numerous challenging sequences, and evaluate them with different performance metrics. The qualitative and quantitative comparative results demonstrate the strength and weakness of these algorithms.
Methods to Improve the Maintenance of the Earth Catalog of Satellites During Severe Solar Storms
NASA Technical Reports Server (NTRS)
Wilkin, Paul G.; Tolson, Robert H.
1998-01-01
The objective of this thesis is to investigate methods to improve the ability to maintain the inventory of orbital elements of Earth satellites during periods of atmospheric disturbance brought on by severe solar activity. Existing techniques do not account for such atmospheric dynamics, resulting in tracking errors of several seconds in predicted crossing time. Two techniques are examined to reduce of these tracking errors. First, density predicted from various atmospheric models is fit to the orbital decay rate for a number of satellites. An orbital decay model is then developed that could be used to reduce tracking errors by accounting for atmospheric changes. The second approach utilizes a Kalman filter to estimate the orbital decay rate of a satellite after every observation. The new information is used to predict the next observation. Results from the first approach demonstrated the feasibility of building an orbital decay model based on predicted atmospheric density. Correlation of atmospheric density to orbital decay was as high as 0.88. However, it is clear that contemporary: atmospheric models need further improvement in modeling density perturbations polar region brought on by solar activity. The second approach resulted in a dramatic reduction in tracking errors for certain satellites during severe solar Storms. For example, in the limited cases studied, the reduction in tracking errors ranged from 79 to 25 percent.
Sawicki, Piotr
2018-01-01
The paper presents the results of testing a proposed image-based point clouds measuring method for geometric parameters determination of a railway track. The study was performed based on a configuration of digital images and reference control network. A DSLR (digital Single-Lens-Reflex) Nikon D5100 camera was used to acquire six digital images of the tested section of railway tracks. The dense point clouds and the 3D mesh model were generated with the use of two software systems, RealityCapture and PhotoScan, which have implemented different matching and 3D object reconstruction techniques: Multi-View Stereo and Semi-Global Matching, respectively. The study found that both applications could generate appropriate 3D models. Final meshes of 3D models were filtered with the MeshLab software. The CloudCompare application was used to determine the track gauge and cant for defined cross-sections, and the results obtained from point clouds by dense image matching techniques were compared with results of direct geodetic measurements. The obtained RMS difference in the horizontal (gauge) and vertical (cant) plane was RMS∆ < 0.45 mm. The achieved accuracy meets the accuracy condition of measurements and inspection of the rail tracks (error m < 1 mm), specified in the Polish branch railway instruction Id-14 (D-75) and the European technical norm EN 13848-4:2011. PMID:29509679
Gabara, Grzegorz; Sawicki, Piotr
2018-03-06
The paper presents the results of testing a proposed image-based point clouds measuring method for geometric parameters determination of a railway track. The study was performed based on a configuration of digital images and reference control network. A DSLR (digital Single-Lens-Reflex) Nikon D5100 camera was used to acquire six digital images of the tested section of railway tracks. The dense point clouds and the 3D mesh model were generated with the use of two software systems, RealityCapture and PhotoScan, which have implemented different matching and 3D object reconstruction techniques: Multi-View Stereo and Semi-Global Matching, respectively. The study found that both applications could generate appropriate 3D models. Final meshes of 3D models were filtered with the MeshLab software. The CloudCompare application was used to determine the track gauge and cant for defined cross-sections, and the results obtained from point clouds by dense image matching techniques were compared with results of direct geodetic measurements. The obtained RMS difference in the horizontal (gauge) and vertical (cant) plane was RMS∆ < 0.45 mm. The achieved accuracy meets the accuracy condition of measurements and inspection of the rail tracks (error m < 1 mm), specified in the Polish branch railway instruction Id-14 (D-75) and the European technical norm EN 13848-4:2011.
Lagrangian 3D tracking of fluorescent microscopic objects in motion
NASA Astrophysics Data System (ADS)
Darnige, T.; Figueroa-Morales, N.; Bohec, P.; Lindner, A.; Clément, E.
2017-05-01
We describe the development of a tracking device, mounted on an epi-fluorescent inverted microscope, suited to obtain time resolved 3D Lagrangian tracks of fluorescent passive or active micro-objects in microfluidic devices. The system is based on real-time image processing, determining the displacement of a x, y mechanical stage to keep the chosen object at a fixed position in the observation frame. The z displacement is based on the refocusing of the fluorescent object determining the displacement of a piezo mover keeping the moving object in focus. Track coordinates of the object with respect to the microfluidic device as well as images of the object are obtained at a frequency of several tenths of Hertz. This device is particularly well adapted to obtain trajectories of motile micro-organisms in microfluidic devices with or without flow.
Lagrangian 3D tracking of fluorescent microscopic objects in motion.
Darnige, T; Figueroa-Morales, N; Bohec, P; Lindner, A; Clément, E
2017-05-01
We describe the development of a tracking device, mounted on an epi-fluorescent inverted microscope, suited to obtain time resolved 3D Lagrangian tracks of fluorescent passive or active micro-objects in microfluidic devices. The system is based on real-time image processing, determining the displacement of a x, y mechanical stage to keep the chosen object at a fixed position in the observation frame. The z displacement is based on the refocusing of the fluorescent object determining the displacement of a piezo mover keeping the moving object in focus. Track coordinates of the object with respect to the microfluidic device as well as images of the object are obtained at a frequency of several tenths of Hertz. This device is particularly well adapted to obtain trajectories of motile micro-organisms in microfluidic devices with or without flow.
The role of "rescue saccades" in tracking objects through occlusions.
Zelinsky, Gregory J; Todor, Andrei
2010-12-29
We hypothesize that our ability to track objects through occlusions is mediated by timely assistance from gaze in the form of "rescue saccades"-eye movements to tracked objects that are in danger of being lost due to impending occlusion. Observers tracked 2-4 target sharks (out of 9) for 20 s as they swam through a rendered 3D underwater scene. Targets were either allowed to enter into occlusions (occlusion trials) or not (no occlusion trials). Tracking accuracy with 2-3 targets was ≥ 92% regardless of target occlusion but dropped to 74% on occlusion trials with four targets (no occlusion trials remained accurate; 83%). This pattern was mirrored in the frequency of rescue saccades. Rescue saccades accompanied approximatlely 50% of the Track 2-3 target occlusions, but only 34% of the Track 4 occlusions. Their frequency also decreased with increasing distance between a target and the nearest other object, suggesting that it is the potential for target confusion that summons a rescue saccade, not occlusion itself. These findings provide evidence for a tracking system that monitors for events that might cause track loss (e.g., occlusions) and requests help from the oculomotor system to resolve these momentary crises. As the number of crises increase with the number of targets, some requests for help go unsatisfied, resulting in degraded tracking.
Point pattern match-based change detection in a constellation of previously detected objects
Paglieroni, David W.
2016-06-07
A method and system is provided that applies attribute- and topology-based change detection to objects that were detected on previous scans of a medium. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, detection strength, size, elongation, orientation, etc. The locations define a three-dimensional network topology forming a constellation of previously detected objects. The change detection system stores attributes of the previously detected objects in a constellation database. The change detection system detects changes by comparing the attributes and topological consistency of newly detected objects encountered during a new scan of the medium to previously detected objects in the constellation database. The change detection system may receive the attributes of the newly detected objects as the objects are detected by an object detection system in real time.
Lu, Shengfu; Xu, Jiying; Li, Mi; Xue, Jia; Lu, Xiaofeng; Feng, Lei; Fu, Bingbing; Wang, Gang; Zhong, Ning; Hu, Bin
2017-10-01
Objective To compare the attentional bias of depressed patients and non-depressed control subjects and examine the effects of age using eye-tracking technology in a free-viewing set of tasks. Methods Patients with major depressive disorder (MDD) and non-depressed control subjects completed an eye-tracking task to assess attention of processing negative, positive and neutral facial expressions. In this cross-sectional study, the tasks were separated in two types (neutral versus happy faces and neutral versus sad faces) and assessed in two age groups ('young' [18-30 years] and 'middle-aged' [31-55 years]). Results Compared with non-depressed control subjects ( n = 75), patients with MDD ( n = 90) had a significant reduced positive attentional bias and enhanced negative attentional bias irrespective of age. The positive attentional bias in 'middle-aged' patients with MDD was significantly lower than in 'young' patients, although there was no difference between the two age groups in negative attentional bias. Conclusions These results confirm that there are emotional attentional biases in patients with MDD and that positive attentional biases are influenced by age.
Multiple Objects Fusion Tracker Using a Matching Network for Adaptively Represented Instance Pairs
Oh, Sang-Il; Kang, Hang-Bong
2017-01-01
Multiple-object tracking is affected by various sources of distortion, such as occlusion, illumination variations and motion changes. Overcoming these distortions by tracking on RGB frames, such as shifting, has limitations because of material distortions caused by RGB frames. To overcome these distortions, we propose a multiple-object fusion tracker (MOFT), which uses a combination of 3D point clouds and corresponding RGB frames. The MOFT uses a matching function initialized on large-scale external sequences to determine which candidates in the current frame match with the target object in the previous frame. After conducting tracking on a few frames, the initialized matching function is fine-tuned according to the appearance models of target objects. The fine-tuning process of the matching function is constructed as a structured form with diverse matching function branches. In general multiple object tracking situations, scale variations for a scene occur depending on the distance between the target objects and the sensors. If the target objects in various scales are equally represented with the same strategy, information losses will occur for any representation of the target objects. In this paper, the output map of the convolutional layer obtained from a pre-trained convolutional neural network is used to adaptively represent instances without information loss. In addition, MOFT fuses the tracking results obtained from each modality at the decision level to compensate the tracking failures of each modality using basic belief assignment, rather than fusing modalities by selectively using the features of each modality. Experimental results indicate that the proposed tracker provides state-of-the-art performance considering multiple objects tracking (MOT) and KITTIbenchmarks. PMID:28420194
Roux, Paul; Brunet-Gouet, Eric; Passerieux, Christine; Ramus, Franck
2016-03-01
Schizophrenia is associated with poor theory of mind (ToM), particularly in the attribution of intentions to others. It is also associated with abnormal gaze behaviours and contextual processing. This study investigated to what extent impaired ToM in patients with schizophrenia is related to abnormal processing of social context. We evaluated ToM using a nonverbal intention attribution task based on comic strips depicting social/nonsocial and contextual/noncontextual events while eye movements were recorded. Eye-tracking was used to assess processing time dedicated to visual cues contained in regions of interest identified in a pilot study. We measured cognitive contextual control on a separate task. We tested 29 patients with schizophrenia and 29 controls. Compared with controls, patients were slower in intention attribution but not in physical reasoning. They looked longer than controls at contextual cues displayed in the first 2 context pictures of the comic strips, and this difference was greater for intention attribution than for physical reasoning. We found no group difference in time spent looking at noncontextual cues. Patients' impairment in contextual control did not explain their increased reaction time and gaze duration on contextual cues during intention attribution. Difficulty may not have been equivalent between intention attribution and physical reasoning conditions. Overall, schizophrenia was characterized by a delay in intention attribution related to a slowdown of social context processing that was not explained by worse executive contextual control.
Roux, Paul; Brunet-Gouet, Eric; Passerieux, Christine; Ramus, Franck
2016-01-01
Background Schizophrenia is associated with poor theory of mind (ToM), particularly in the attribution of intentions to others. It is also associated with abnormal gaze behaviours and contextual processing. This study investigated to what extent impaired ToM in patients with schizophrenia is related to abnormal processing of social context. Methods We evaluated ToM using a nonverbal intention attribution task based on comic strips depicting social/nonsocial and contextual/noncontextual events while eye movements were recorded. Eye-tracking was used to assess processing time dedicated to visual cues contained in regions of interest identified in a pilot study. We measured cognitive contextual control on a separate task. Results We tested 29 patients with schizophrenia and 29 controls. Compared with controls, patients were slower in intention attribution but not in physical reasoning. They looked longer than controls at contextual cues displayed in the first 2 context pictures of the comic strips, and this difference was greater for intention attribution than for physical reasoning. We found no group difference in time spent looking at noncontextual cues. Patients’ impairment in contextual control did not explain their increased reaction time and gaze duration on contextual cues during intention attribution. Limitations Difficulty may not have been equivalent between intention attribution and physical reasoning conditions. Conclusion Overall, schizophrenia was characterized by a delay in intention attribution related to a slowdown of social context processing that was not explained by worse executive contextual control. PMID:26836621
Fast object reconstruction in block-based compressive low-light-level imaging
NASA Astrophysics Data System (ADS)
Ke, Jun; Sui, Dong; Wei, Ping
2014-11-01
In this paper we propose a simply yet effective and efficient method for long-term object tracking. Different from traditional visual tracking method which mainly depends on frame-to-frame correspondence, we combine high-level semantic information with low-level correspondences. Our framework is formulated in a confidence selection framework, which allows our system to recover from drift and partly deal with occlusion problem. To summarize, our algorithm can be roughly decomposed in a initialization stage and a tracking stage. In the initialization stage, an offline classifier is trained to get the object appearance information in category level. When the video stream is coming, the pre-trained offline classifier is used for detecting the potential target and initializing the tracking stage. In the tracking stage, it consists of three parts which are online tracking part, offline tracking part and confidence judgment part. Online tracking part captures the specific target appearance information while detection part localizes the object based on the pre-trained offline classifier. Since there is no data dependence between online tracking and offline detection, these two parts are running in parallel to significantly improve the processing speed. A confidence selection mechanism is proposed to optimize the object location. Besides, we also propose a simple mechanism to judge the absence of the object. If the target is lost, the pre-trained offline classifier is utilized to re-initialize the whole algorithm as long as the target is re-located. During experiment, we evaluate our method on several challenging video sequences and demonstrate competitive results.
Radar cross section measurements of a scale model of the space shuttle orbiter vehicle
NASA Technical Reports Server (NTRS)
Yates, W. T.
1978-01-01
A series of microwave measurements was conducted to determine the radar cross section of the Space Shuttle Orbiter vehicle at a frequency and at aspect angles applicable to re-entry radar acquisition and tracking. The measurements were performed in a microwave anechoic chamber using a 1/15th scale model and a frequency applicable to C-band tracking radars. The data were digitally recorded and processed to yield statistical descriptions useful for prediction of orbiter re-entry detection and tracking ranges.
Kernelized correlation tracking with long-term motion cues
NASA Astrophysics Data System (ADS)
Lv, Yunqiu; Liu, Kai; Cheng, Fei
2018-04-01
Robust object tracking is a challenging task in computer vision due to interruptions such as deformation, fast motion and especially, occlusion of tracked object. When occlusions occur, image data will be unreliable and is insufficient for the tracker to depict the object of interest. Therefore, most trackers are prone to fail under occlusion. In this paper, an occlusion judgement and handling method based on segmentation of the target is proposed. If the target is occluded, the speed and direction of it must be different from the objects occluding it. Hence, the value of motion features are emphasized. Considering the efficiency and robustness of Kernelized Correlation Filter Tracking (KCF), it is adopted as a pre-tracker to obtain a predicted position of the target. By analyzing long-term motion cues of objects around this position, the tracked object is labelled. Hence, occlusion could be detected easily. Experimental results suggest that our tracker achieves a favorable performance and effectively handles occlusion and drifting problems.
Grouping and trajectory storage in multiple object tracking: impairments due to common item motions.
Suganuma, Mutsumi; Yokosawa, Kazuhiko
2006-01-01
In our natural viewing, we notice that objects change their locations across space and time. However, there has been relatively little consideration of the role of motion information in the construction and maintenance of object representations. We investigated this question in the context of the multiple object tracking (MOT) paradigm, wherein observers must keep track of target objects as they move randomly amid featurally identical distractors. In three experiments, we observed impairments in tracking ability when the motions of the target and distractor items shared particular properties. Specifically, we observed impairments when the target and distractor items were in a chasing relationship or moved in a uniform direction. Surprisingly, tracking ability was impaired by these manipulations even when observers failed to notice them. Our results suggest that differentiable trajectory information is an important factor in successful performance of MOT tasks. More generally, these results suggest that various types of common motion can serve as cues to form more global object representations even in the absence of other grouping cues.
Keeping on Track: Performance Profiles of Low Performers in Academic Educational Tracks
ERIC Educational Resources Information Center
Reed, Helen C.; van Wesel, Floryt; Ouwehand, Carolijn; Jolles, Jelle
2015-01-01
In countries with high differentiation between academic and vocational education, an individual's future prospects are strongly determined by the educational track to which he or she is assigned. This large-scale, cross-sectional study focuses on low-performing students in academic tracks who face being moved to a vocational track. If more is…
Kentucky | Midmarket Solar Policies in the United States | Solar Research |
NREL Kentucky Kentucky No renewable portfolio standard Carve-out: None Tracking system Attribute Tracking System (PJM-GATS) Kentucky currently has no state renewable portfolio standard or goal and no demand for renewable energy certificates (RECs). However, solar customers may sell RECs to the
NucliTrack: an integrated nuclei tracking application.
Cooper, Sam; Barr, Alexis R; Glen, Robert; Bakal, Chris
2017-10-15
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. © The Author(s) 2017. Published by Oxford University Press.
Nonlinear Motion Tracking by Deep Learning Architecture
NASA Astrophysics Data System (ADS)
Verma, Arnav; Samaiya, Devesh; Gupta, Karunesh K.
2018-03-01
In the world of Artificial Intelligence, object motion tracking is one of the major problems. The extensive research is being carried out to track people in crowd. This paper presents a unique technique for nonlinear motion tracking in the absence of prior knowledge of nature of nonlinear path that the object being tracked may follow. We achieve this by first obtaining the centroid of the object and then using the centroid as the current example for a recurrent neural network trained using real-time recurrent learning. We have tweaked the standard algorithm slightly and have accumulated the gradient for few previous iterations instead of using just the current iteration as is the norm. We show that for a single object, such a recurrent neural network is highly capable of approximating the nonlinearity of its path.
ERIC Educational Resources Information Center
O'Hearn, Kirsten; Hoffman, James E.; Landau, Barbara
2010-01-01
The ability to track moving objects, a crucial skill for mature performance on everyday spatial tasks, has been hypothesized to require a specialized mechanism that may be available in infancy (i.e. indexes). Consistent with the idea of specialization, our previous work showed that object tracking was more impaired than a matched spatial memory…
Emergency Medicine Resident Perceptions of Medical Professionalism.
Jauregui, Joshua; Gatewood, Medley O; Ilgen, Jonathan S; Schaninger, Caitlin; Strote, Jared
2016-05-01
Medical professionalism is a core competency for emergency medicine (EM) trainees; but defining professionalism remains challenging, leading to difficulties creating objectives and performing assessment. Because professionalism is dynamic, culture-specific, and often taught by modeling, an exploration of trainees' perceptions can highlight their educational baseline and elucidate the importance they place on general conventional professionalism domains. To this end, our objective was to assess the relative value EM residents place on traditional components of professionalism. We performed a cross-sectional, multi-institutional survey of incoming and graduating EM residents at four programs. The survey was developed using the American Board of Internal Medicine's "Project Professionalism" and the Accreditation Council of Graduate Medical Education definition of professionalism competency. We identified 27 attributes within seven domains: clinical excellence, humanism, accountability, altruism, duty and service, honor and integrity, and respect for others. Residents were asked to rate each attribute on a 10-point scale. We analyzed data to assess variance across attributes as well as differences between residents at different training levels or different institutions. Of the 114 residents eligible, 100 (88%) completed the survey. The relative value assigned to different professional attributes varied considerably, with those in the altruism domain valued significantly lower and those in the "respect for others" and "honor and integrity" valued significantly higher (p<0.001). Significant differences were found between interns and seniors for five attributes primarily in the "duty and service" domain (p<0.05). Among different residencies, significant differences were found with attributes within the "altruism" and "duty and service" domains (p<0.05). Residents perceive differences in the relative importance of traditionally defined professional attributes and this may be useful to educators. Explanations for these differences are hypothesized, as are the potential implications for professionalism education. Because teaching professional behavior is taught most effectively via behavior modeling, faculty awareness of resident values and faculty development to address potential gaps may improve professionalism education.
Satellite accelerometer measurements of neutral density and winds during geomagnetic storms
NASA Technical Reports Server (NTRS)
Marcos, F. A.; Forbes, J. M.
1986-01-01
A new thermospheric wind measurement technique is reported which is based on a Satellite Electrostatic Triaxial Accelerometer (SETA) system capable of accurately measuring accelerations in the satellite's in-track, cross-track and radial directions. Data obtained during two time periods are presented. The first data set describes cross-track winds measured between 170 and 210 km during a 5-day period (25 to 29 March 1979) of mostly high geomagnetic activity. In the second data set, cross-track winds and neutral densities from SETA and exospheric temperatures from the Millstone Hill incoherent scatter radar are examined during an isolated magnetic substorm occurring on 21 March 1979. A polar thermospheric wind circulation consisting of a two cell horizontal convection pattern is reflected in both sets of cross-track acceleration measurements. The density response is highly asymmetric with respect to its day/night behavior. Latitude structures of the density response at successive times following the substorm peak suggest the equatorward propagation of a disturbance with a phase speed between 300 and 600 m/s. A deep depression in the density at high latitudes (less than 70 deg) is evident in conjunction with this phenomenon. The more efficient propagation of the disturbance to lower latitudes during the night is probably due to the midnight surge effect.
ERIC Educational Resources Information Center
Helm, David Jay
2017-01-01
This study examines the background information and the components of N.L.P., being eye movements, use of predicates, and posturing, as they apply to improving rapport and empathy between track/cross country coaches and their significant others in the arena of competition to help alleviate the inherent stressors.
NASA Technical Reports Server (NTRS)
Phillips, Veronica J.
2017-01-01
STI is for a fact sheet on the Space Object Query Tool being created by the MDC. When planning launches, NASA must first factor in the tens of thousands of objects already in orbit around the Earth. The number of human-made objects, including nonfunctional spacecraft, abandoned launch vehicle stages, mission-related debris and fragmentation debris orbiting Earth has grown steadily since Sputnik 1 was launched in 1957. Currently, the U.S. Department of Defenses Joint Space Operations Center, or JSpOC, tracks over 15,000 distinct objects and provides data for more than 40,000 objects via its Space-Track program, found at space-track.org.
A Deep-Structured Conditional Random Field Model for Object Silhouette Tracking
Shafiee, Mohammad Javad; Azimifar, Zohreh; Wong, Alexander
2015-01-01
In this work, we introduce a deep-structured conditional random field (DS-CRF) model for the purpose of state-based object silhouette tracking. The proposed DS-CRF model consists of a series of state layers, where each state layer spatially characterizes the object silhouette at a particular point in time. The interactions between adjacent state layers are established by inter-layer connectivity dynamically determined based on inter-frame optical flow. By incorporate both spatial and temporal context in a dynamic fashion within such a deep-structured probabilistic graphical model, the proposed DS-CRF model allows us to develop a framework that can accurately and efficiently track object silhouettes that can change greatly over time, as well as under different situations such as occlusion and multiple targets within the scene. Experiment results using video surveillance datasets containing different scenarios such as occlusion and multiple targets showed that the proposed DS-CRF approach provides strong object silhouette tracking performance when compared to baseline methods such as mean-shift tracking, as well as state-of-the-art methods such as context tracking and boosted particle filtering. PMID:26313943
Störmer, Viola S; Winther, Gesche N; Li, Shu-Chen; Andersen, Søren K
2013-03-20
Keeping track of multiple moving objects is an essential ability of visual perception. However, the mechanisms underlying this ability are not well understood. We instructed human observers to track five or seven independent randomly moving target objects amid identical nontargets and recorded steady-state visual evoked potentials (SSVEPs) elicited by these stimuli. Visual processing of moving targets, as assessed by SSVEP amplitudes, was continuously facilitated relative to the processing of identical but irrelevant nontargets. The cortical sources of this enhancement were located to areas including early visual cortex V1-V3 and motion-sensitive area MT, suggesting that the sustained multifocal attentional enhancement during multiple object tracking already operates at hierarchically early stages of visual processing. Consistent with this interpretation, the magnitude of attentional facilitation during tracking in a single trial predicted the speed of target identification at the end of the trial. Together, these findings demonstrate that attention can flexibly and dynamically facilitate the processing of multiple independent object locations in early visual areas and thereby allow for tracking of these objects.
Unsupervised markerless 3-DOF motion tracking in real time using a single low-budget camera.
Quesada, Luis; León, Alejandro J
2012-10-01
Motion tracking is a critical task in many computer vision applications. Existing motion tracking techniques require either a great amount of knowledge on the target object or specific hardware. These requirements discourage the wide spread of commercial applications based on motion tracking. In this paper, we present a novel three degrees of freedom motion tracking system that needs no knowledge on the target object and that only requires a single low-budget camera that can be found installed in most computers and smartphones. Our system estimates, in real time, the three-dimensional position of a nonmodeled unmarked object that may be nonrigid, nonconvex, partially occluded, self-occluded, or motion blurred, given that it is opaque, evenly colored, enough contrasting with the background in each frame, and that it does not rotate. Our system is also able to determine the most relevant object to track in the screen. Our proposal does not impose additional constraints, therefore it allows a market-wide implementation of applications that require the estimation of the three position degrees of freedom of an object.
Russell, Cristel Antonia; Swasy, John L.; Russell, Dale Wesley; Engel, Larry
2017-01-01
Risk warning or disclosure information in advertising is only effective in correcting consumers’ judgments if enough cognitive capacity is available to process that information. Hence, comprehension of verbal warnings in TV commercials may suffer if accompanied by positive visual elements. This research addresses this concern about cross-modality interference in the context of direct-to-consumer (DTC) pharmaceutical commercials in the United States by experimentally testing whether positive facial expressions reduce consumers’ understanding of the mandated health warning. A content analysis of a sample of DTC commercials reveals that positive facial expressions are more prevalent during the verbal warning act of the commercials than during the other acts. An eye-tracking experiment conducted with specially produced DTC commercials, which vary the valence of characters’ facial expressions during the health warning, provides evidence that happy faces reduce objective comprehension of the warning. PMID:29269979
Promotion Rates for Assistant and Associate Professors in Obstetrics and Gynecology
Rayburn, William F.; Schrader, Ronald M.; Fullilove, Anne M.; Rutledge, Teresa L.; Phelan, Sharon T.; Gener, Yolanda
2015-01-01
OBJECTIVE To estimate promotion rates of physician faculty members in obstetrics and gynecology during the past 30 years METHODS Data were collected annually by the Association of American Medical Colleges from every school between 1980 and 2009 for first-time assistant and associate professors to determine whether and when they were promoted. Data for full-time physician faculty were aggregated by decade (1980–1989, 1990–1999, 2000–2009). Faculty were included if they remained in academia for 10 years after beginning in rank. Data were analyzed by constructing estimated promotion curves and extracting 6-year and 10-year promotion rates. RESULTS The 10-year promotion rates (adjusted for attrition) declined significantly for assistant professors from 35% in 1980–89 to 32% in 1990–99 to 26% in 2000–09 (p < 0.001); and for associate professors from 37% to 32% to 26% respectively (p < 0.005). These declines likely resulted from changes in faculty composition. The most recent 15 years saw a steady rise in the proportion of entry-level faculty who were women (now 2:1) and primarily on the non-tenure track. The rising number of faculty in general obstetrics and gynecology had lower promotion probabilities than those in the subspecialties (OR = 0.16, p < 0.001). Female faculty on the non-tenure track had lower promotion rates than males in the non-tenure track, males in the tenure track, and females in the tenure track (ORs ≤ 0.8, p < 0.01). CONCLUSION A decline in promotion rates during the past 30 years may be attributable to changes in faculty composition. PMID:22525914
Versaggi, Cassandra L.; King, Christopher P.; Meyer, Paul J.
2016-01-01
Rationale Some individuals are particularly responsive to reward-associated stimuli (“cues”), including the effects of these cues on craving and relapse to drug-seeking behavior. In the cases of nicotine and alcohol, cues may acquire these abilities via the incentive-enhancing properties of the drug. Objectives To determine the interaction between cue-responsivity and nicotine reinforcement, we studied the patterns of nicotine self-administration in rats categorized based on their tendency to approach a food predictive cue (“sign-trackers”) or a reward-delivery location (“goal-trackers”). In a second experiment, we determined whether nicotine and ethanol altered the incentive value of a food cue. Methods Rats were classified as sign- or goal-trackers during a Pavlovian conditioned approach paradigm. Rats then self-administered intravenous nicotine (0.03 mg/kg infusions) followed by extinction and cue induced reinstatement tests. We also tested the effects of nicotine (0.4 mg/kg base s.c.) or ethanol (0.7 g/kg i.p.) on the approach to, and reinforcing efficacy of, a food cue. Results Sign-trackers showed greater reinstatement in response to a nicotine cue. Further, nicotine enhanced sign-tracking but not goal-tracking to a food cue, and also enhanced responding for the food cue during the conditioned reinforcement test. Conversely, ethanol reduced sign-tracking and increased goal-tracking, but had no effect on conditioned reinforcement. Conclusions Our studies demonstrate that the tendency to attribute incentive value to a food cue predicts enhanced cue-induced reinstatement. Additionally, the incentive value of food cues is differentially modulated by nicotine and ethanol, which may be related to the reinforcing effects of these drugs. PMID:27282365
An object detection and tracking system for unmanned surface vehicles
NASA Astrophysics Data System (ADS)
Yang, Jian; Xiao, Yang; Fang, Zhiwen; Zhang, Naiwen; Wang, Li; Li, Tao
2017-10-01
Object detection and tracking are critical parts of unmanned surface vehicles(USV) to achieve automatic obstacle avoidance. Off-the-shelf object detection methods have achieved impressive accuracy in public datasets, though they still meet bottlenecks in practice, such as high time consumption and low detection quality. In this paper, we propose a novel system for USV, which is able to locate the object more accurately while being fast and stable simultaneously. Firstly, we employ Faster R-CNN to acquire several initial raw bounding boxes. Secondly, the image is segmented to a few superpixels. For each initial box, the superpixels inside will be grouped into a whole according to a combination strategy, and a new box is thereafter generated as the circumscribed bounding box of the final superpixel. Thirdly, we utilize KCF to track these objects after several frames, Faster-RCNN is again used to re-detect objects inside tracked boxes to prevent tracking failure as well as remove empty boxes. Finally, we utilize Faster R-CNN to detect objects in the next image, and refine object boxes by repeating the second module of our system. The experimental results demonstrate that our system is fast, robust and accurate, which can be applied to USV in practice.
Design and Efficiency Analysis of Operational Scenarios for Space Situational Awareness Radar System
NASA Astrophysics Data System (ADS)
Choi, E. J.; Cho, S.; Jo, J. H.; Park, J.; Chung, T.; Park, J.; Jeon, H.; Yun, A.; Lee, Y.
In order to perform the surveillance and tracking of space objects, optical and radar sensors are the technical components for space situational awareness system. Especially, space situational awareness radar system in combination with optical sensors network plays an outstanding role for space situational awareness. At present, OWL-Net(Optical Wide Field patrol Network) optical system, which is the only infra structures for tracking of space objects in Korea is very limited in all-weather and observation time. Therefore, the development of radar system capable of continuous operation is becoming an essential space situational awareness element. Therefore, for an efficient space situational awareness at the current state, the strategy of the space situational awareness radar development should be considered. The purpose of this paper is to analyze the efficiency of radar system for detection and tracking of space objects. The detection capabilities are limited to an altitude of 2,000 km with debris size of 1 m2 in radar cross section (RCS) for the radar operating frequencies of L, S, C, X, and Ku-band. The power budget analysis results showed that the maximum detection range of 2,000km can be achieved with the transmitted power of 900 kW, transmit and receive antenna gains of 40 dB and 43 dB, respectively, pulse width of 2 ms, and a signal processing gain of 13.3dB, at frequency of 1.3GHz. The required signal-to-noise ratio (SNR) was assumed to be 12.6 dB for probability of detection of 80% with false alarm rate 10-6. Through the efficiency analysis and trade-off study, the key parameters of the radar system are designed. As a result, this research will provide the guideline for the conceptual design of space situational awareness system.
Development of the ZEUS central tracking detector
NASA Astrophysics Data System (ADS)
Brooks, C. B.; Bullock, F. W.; Cashmore, R. J.; Devenish, R. C.; Foster, B.; Fraser, T. J.; Gibson, M. D.; Gilmore, R. S.; Gingrich, D.; Harnew, N.; Hart, J. C.; Heath, G. P.; Hiddleston, J.; Holmes, A. R.; Jamdagni, A. K.; Jones, T. W.; Llewellyn, T. J.; Long, K. R.; Lush, G. J.; Malos, J.; Martin, N. C.; McArthur, I.; McCubbin, N. A.; McQuillan, D.; Miller, D. B.; Mobayyen, M. M.; Morgado, C.; Nash, J.; Nixon, G.; Parham, A. G.; Payne, B. T.; Roberts, J. H. C.; Salmon, G.; Saxon, D. H.; Sephton, A. J.; Shaw, D.; Shaw, T. B.; Shield, P. D.; Shulman, J.; Silvester, I.; Smith, S.; Strachan, D. E.; Tapper, R. J.; Tkaczyk, S. M.; Toudup, L. W.; Wallis, E. W.; Wastie, R.; Wells, J.; White, D. J.; Wilson, F. F.; Yeo, K. L.; ZEUS-UK Collaboration
1989-11-01
The design concept and development of the ZEUS central tracking detector is described. This is a cylindrical drift chamber designed for track reconstruction, electron identification and event triggering in a high-crossing-rate, high-magnetic-field environment.
Multi-object detection and tracking technology based on hexagonal opto-electronic detector
NASA Astrophysics Data System (ADS)
Song, Yong; Hao, Qun; Li, Xiang
2008-02-01
A novel multi-object detection and tracking technology based on hexagonal opto-electronic detector is proposed, in which (1) a new hexagonal detector, which is composed of 6 linear CCDs, has been firstly developed to achieve the field of view of 360 degree, (2) to achieve the detection and tracking of multi-object with high speed, the object recognition criterions of Object Signal Width Criterion (OSWC) and Horizontal Scale Ratio Criterion (HSRC) are proposed. In this paper, Simulated Experiments have been carried out to verify the validity of the proposed technology, which show that the detection and tracking of multi-object can be achieved with high speed by using the proposed hexagonal detector and the criterions of OSWC and HSRC, indicating that the technology offers significant advantages in Photo-electric Detection, Computer Vision, Virtual Reality, Augment Reality, etc.
3D landslide motion from a UAV-derived time-series of morphological attributes
NASA Astrophysics Data System (ADS)
Valasia Peppa, Maria; Mills, Jon Philip; Moore, Philip; Miller, Pauline; Chambers, Jon
2017-04-01
Landslides are recognised as dynamic and significantly hazardous phenomena. Time-series observations can improve the understanding of a landslide's complex behaviour and aid assessment of its geometry and kinematics. Conventional quantification of landslide motion involves the installation of survey markers into the ground at discrete locations and periodic observations over time. However, such surveying is labour intensive, provides limited spatial resolution, is occasionally hazardous for steep terrain, or even impossible for inaccessible mountainous areas. The emergence of mini unmanned aerial vehicles (UAVs) equipped with off-the-shelf compact cameras, alongside the structure-from-motion (SfM) photogrammetric pipeline and modern pixel-based matching approaches, has expedited the automatic generation of high resolution digital elevation models (DEMs). Moreover, cross-correlation functions applied to finely co-registered consecutive orthomosaics and/or DEMs have been widely used to determine the displacement of moving features in an automated way, resulting in high spatial resolution motion vectors. This research focuses on estimating the 3D displacement field of an active slow moving earth-slide earth-flow landslide located in Lias mudrocks of North Yorkshire, UK, with the ultimate aim of assessing landslide deformation patterns. The landslide extends approximately 290 m E-W and 230 m N-S, with an average slope of 12˚ and 50 m elevation difference from N-S. Cross-correlation functions were applied to an eighteen-month duration, UAV-derived, time-series of morphological attributes in order to determine motion vectors for subsequent landslide analysis. A self-calibrating bundle adjustment was firstly incorporated into the SfM pipeline and utilised to process imagery acquired using a Panasonic Lumix DMC-LX5 compact camera from a mini fixed-wing Quest 300 UAV, with 2 m wingspan and maximum 5 kg payload. Data from six field campaigns were used to generate a DEM time-series at 6 cm spatial resolution. DEMs were georeferenced into a common reference frame using control information from surveyed ground control points. The accuracy of the co-registration was estimated from planimetric and vertical RMS errors at independent checkpoints as 4 cm and 3 cm respectively. Afterwards, various morphological attributes, including shaded relief, curvature and openness were calculated from the UAV-derived DEMs. These attributes are indicative of the local structures of discernible geomorphological features (e.g. scarps, ridges, cracks, etc.), the motion of which can be monitored using the cross-correlation algorithm. Multiple experiments were conducted to test the performance of the cross-correlation function implemented on successive epochs. Two benchmark datasets were used for validation of the cross-correlation results: a) the motion vectors generated from the surveyed 3D position of installed markers; b) the calculated displacements of features, manually tracked from successive UAV-derived orthomosaics. Both benchmark datasets detected a maximum planimetric displacement of approximately 1 m at the foot of the landslide, with a dominant N-S orientation, between December 2014 and May 2016. Preliminary cross-correlation results illustrated a similar planimetric motion in both magnitude and orientation, however user intervention was required to filter spurious displacement vectors.
Li, Liyuan; Huang, Weimin; Gu, Irene Yu-Hua; Luo, Ruijiang; Tian, Qi
2008-10-01
Efficiency and robustness are the two most important issues for multiobject tracking algorithms in real-time intelligent video surveillance systems. We propose a novel 2.5-D approach to real-time multiobject tracking in crowds, which is formulated as a maximum a posteriori estimation problem and is approximated through an assignment step and a location step. Observing that the occluding object is usually less affected by the occluded objects, sequential solutions for the assignment and the location are derived. A novel dominant color histogram (DCH) is proposed as an efficient object model. The DCH can be regarded as a generalized color histogram, where dominant colors are selected based on a given distance measure. Comparing with conventional color histograms, the DCH only requires a few color components (31 on average). Furthermore, our theoretical analysis and evaluation on real data have shown that DCHs are robust to illumination changes. Using the DCH, efficient implementations of sequential solutions for the assignment and location steps are proposed. The assignment step includes the estimation of the depth order for the objects in a dispersing group, one-by-one assignment, and feature exclusion from the group representation. The location step includes the depth-order estimation for the objects in a new group, the two-phase mean-shift location, and the exclusion of tracked objects from the new position in the group. Multiobject tracking results and evaluation from public data sets are presented. Experiments on image sequences captured from crowded public environments have shown good tracking results, where about 90% of the objects have been successfully tracked with the correct identification numbers by the proposed method. Our results and evaluation have indicated that the method is efficient and robust for tracking multiple objects (>or= 3) in complex occlusion for real-world surveillance scenarios.
Method and apparatus for imaging through 3-dimensional tracking of protons
NASA Technical Reports Server (NTRS)
Ryan, James M. (Inventor); Macri, John R. (Inventor); McConnell, Mark L. (Inventor)
2001-01-01
A method and apparatus for creating density images of an object through the 3-dimensional tracking of protons that have passed through the object are provided. More specifically, the 3-dimensional tracking of the protons is accomplished by gathering and analyzing images of the ionization tracks of the protons in a closely packed stack of scintillating fibers.
Online Hierarchical Sparse Representation of Multifeature for Robust Object Tracking
Qu, Shiru
2016-01-01
Object tracking based on sparse representation has given promising tracking results in recent years. However, the trackers under the framework of sparse representation always overemphasize the sparse representation and ignore the correlation of visual information. In addition, the sparse coding methods only encode the local region independently and ignore the spatial neighborhood information of the image. In this paper, we propose a robust tracking algorithm. Firstly, multiple complementary features are used to describe the object appearance; the appearance model of the tracked target is modeled by instantaneous and stable appearance features simultaneously. A two-stage sparse-coded method which takes the spatial neighborhood information of the image patch and the computation burden into consideration is used to compute the reconstructed object appearance. Then, the reliability of each tracker is measured by the tracking likelihood function of transient and reconstructed appearance models. Finally, the most reliable tracker is obtained by a well established particle filter framework; the training set and the template library are incrementally updated based on the current tracking results. Experiment results on different challenging video sequences show that the proposed algorithm performs well with superior tracking accuracy and robustness. PMID:27630710
Visual tracking using objectness-bounding box regression and correlation filters
NASA Astrophysics Data System (ADS)
Mbelwa, Jimmy T.; Zhao, Qingjie; Lu, Yao; Wang, Fasheng; Mbise, Mercy
2018-03-01
Visual tracking is a fundamental problem in computer vision with extensive application domains in surveillance and intelligent systems. Recently, correlation filter-based tracking methods have shown a great achievement in terms of robustness, accuracy, and speed. However, such methods have a problem of dealing with fast motion (FM), motion blur (MB), illumination variation (IV), and drifting caused by occlusion (OCC). To solve this problem, a tracking method that integrates objectness-bounding box regression (O-BBR) model and a scheme based on kernelized correlation filter (KCF) is proposed. The scheme based on KCF is used to improve the tracking performance of FM and MB. For handling drift problem caused by OCC and IV, we propose objectness proposals trained in bounding box regression as prior knowledge to provide candidates and background suppression. Finally, scheme KCF as a base tracker and O-BBR are fused to obtain a state of a target object. Extensive experimental comparisons of the developed tracking method with other state-of-the-art trackers are performed on some of the challenging video sequences. Experimental comparison results show that our proposed tracking method outperforms other state-of-the-art tracking methods in terms of effectiveness, accuracy, and robustness.
ERIC Educational Resources Information Center
Yeung, Cheuk Yu; Shum, Kam Hong; Hui, Lucas Chi Kwong; Chu, Samuel Kai Wah; Chan, Tsing Yun; Kuo, Yung Nin; Ng, Yee Ling
2017-01-01
Attributes of teaching and learning contexts provide rich information about how students participate in learning activities. By tracking and analyzing snapshots of these attributes captured continuously throughout the duration of the learning activities, teachers can identify individual students who need special attention and apply different…
Multi-view video segmentation and tracking for video surveillance
NASA Astrophysics Data System (ADS)
Mohammadi, Gelareh; Dufaux, Frederic; Minh, Thien Ha; Ebrahimi, Touradj
2009-05-01
Tracking moving objects is a critical step for smart video surveillance systems. Despite the complexity increase, multiple camera systems exhibit the undoubted advantages of covering wide areas and handling the occurrence of occlusions by exploiting the different viewpoints. The technical problems in multiple camera systems are several: installation, calibration, objects matching, switching, data fusion, and occlusion handling. In this paper, we address the issue of tracking moving objects in an environment covered by multiple un-calibrated cameras with overlapping fields of view, typical of most surveillance setups. Our main objective is to create a framework that can be used to integrate objecttracking information from multiple video sources. Basically, the proposed technique consists of the following steps. We first perform a single-view tracking algorithm on each camera view, and then apply a consistent object labeling algorithm on all views. In the next step, we verify objects in each view separately for inconsistencies. Correspondent objects are extracted through a Homography transform from one view to the other and vice versa. Having found the correspondent objects of different views, we partition each object into homogeneous regions. In the last step, we apply the Homography transform to find the region map of first view in the second view and vice versa. For each region (in the main frame and mapped frame) a set of descriptors are extracted to find the best match between two views based on region descriptors similarity. This method is able to deal with multiple objects. Track management issues such as occlusion, appearance and disappearance of objects are resolved using information from all views. This method is capable of tracking rigid and deformable objects and this versatility lets it to be suitable for different application scenarios.
An object tracking method based on guided filter for night fusion image
NASA Astrophysics Data System (ADS)
Qian, Xiaoyan; Wang, Yuedong; Han, Lei
2016-01-01
Online object tracking is a challenging problem as it entails learning an effective model to account for appearance change caused by intrinsic and extrinsic factors. In this paper, we propose a novel online object tracking with guided image filter for accurate and robust night fusion image tracking. Firstly, frame difference is applied to produce the coarse target, which helps to generate observation models. Under the restriction of these models and local source image, guided filter generates sufficient and accurate foreground target. Then accurate boundaries of the target can be extracted from detection results. Finally timely updating for observation models help to avoid tracking shift. Both qualitative and quantitative evaluations on challenging image sequences demonstrate that the proposed tracking algorithm performs favorably against several state-of-art methods.
EDDIX--a database of ionisation double differential cross sections.
MacGibbon, J H; Emerson, S; Liamsuwan, T; Nikjoo, H
2011-02-01
The use of Monte Carlo track structure is a choice method in biophysical modelling and calculations. To precisely model 3D and 4D tracks, the cross section for the ionisation by an incoming ion, double differential in the outgoing electron energy and angle, is required. However, the double differential cross section cannot be theoretically modelled over the full range of parameters. To address this issue, a database of all available experimental data has been constructed. Currently, the database of Experimental Double Differential Ionisation Cross sections (EDDIX) contains over 1200 digitalised experimentally measured datasets from the 1960s to present date, covering all available ion species (hydrogen to uranium) and all available target species. Double differential cross sections are also presented with the aid of an eight parameter functions fitted to the cross sections. The parameters include projectile species and charge, target nuclear charge and atomic mass, projectile atomic mass and energy, electron energy and deflection angle. It is planned to freely distribute EDDIX and make it available to the radiation research community for use in the analytical and numerical modelling of track structure.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Dongkyu, E-mail: akein@gist.ac.kr; Khalil, Hossam; Jo, Youngjoon
2016-06-28
An image-based tracking system using laser scanning vibrometer is developed for vibration measurement of a rotating object. The proposed system unlike a conventional one can be used where the position or velocity sensor such as an encoder cannot be attached to an object. An image processing algorithm is introduced to detect a landmark and laser beam based on their colors. Then, through using feedback control system, the laser beam can track a rotating object.
Visual object tracking by correlation filters and online learning
NASA Astrophysics Data System (ADS)
Zhang, Xin; Xia, Gui-Song; Lu, Qikai; Shen, Weiming; Zhang, Liangpei
2018-06-01
Due to the complexity of background scenarios and the variation of target appearance, it is difficult to achieve high accuracy and fast speed for object tracking. Currently, correlation filters based trackers (CFTs) show promising performance in object tracking. The CFTs estimate the target's position by correlation filters with different kinds of features. However, most of CFTs can hardly re-detect the target in the case of long-term tracking drifts. In this paper, a feature integration object tracker named correlation filters and online learning (CFOL) is proposed. CFOL estimates the target's position and its corresponding correlation score using the same discriminative correlation filter with multi-features. To reduce tracking drifts, a new sampling and updating strategy for online learning is proposed. Experiments conducted on 51 image sequences demonstrate that the proposed algorithm is superior to the state-of-the-art approaches.
Like a rolling stone: naturalistic visual kinematics facilitate tracking eye movements.
Souto, David; Kerzel, Dirk
2013-02-06
Newtonian physics constrains object kinematics in the real world. We asked whether eye movements towards tracked objects depend on their compliance with those constraints. In particular, the force of gravity constrains round objects to roll on the ground with a particular rotational and translational motion. We measured tracking eye movements towards rolling objects. We found that objects with rotational and translational motion that was congruent with an object rolling on the ground elicited faster tracking eye movements during pursuit initiation than incongruent stimuli. Relative to a condition without rotational component, we compared objects with this motion with a condition in which there was no rotational component, we essentially obtained benefits of congruence, and, to a lesser extent, costs from incongruence. Anticipatory pursuit responses showed no congruence effect, suggesting that the effect is based on visually-driven predictions, not on velocity storage. We suggest that the eye movement system incorporates information about object kinematics acquired by a lifetime of experience with visual stimuli obeying the laws of Newtonian physics.
Autonomous Space Object Catalogue Construction and Upkeep Using Sensor Control Theory
NASA Astrophysics Data System (ADS)
Moretti, N.; Rutten, M.; Bessell, T.; Morreale, B.
The capability to track objects in space is critical to safeguard domestic and international space assets. Infrequent measurement opportunities, complex dynamics and partial observability of orbital state makes the tracking of resident space objects nontrivial. It is not uncommon for human operators to intervene with space tracking systems, particularly in scheduling sensors. This paper details the development of a system that maintains a catalogue of geostationary objects through dynamically tasking sensors in real time by managing the uncertainty of object states. As the number of objects in space grows the potential for collision grows exponentially. Being able to provide accurate assessment to operators regarding costly collision avoidance manoeuvres is paramount; the accuracy of which is highly dependent on how object states are estimated. The system represents object state and uncertainty using particles and utilises a particle filter for state estimation. Particle filters capture the model and measurement uncertainty accurately, allowing for a more comprehensive representation of the state’s probability density function. Additionally, the number of objects in space is growing disproportionally to the number of sensors used to track them. Maintaining precise positions for all objects places large loads on sensors, limiting the time available to search for new objects or track high priority objects. Rather than precisely track all objects our system manages the uncertainty in orbital state for each object independently. The uncertainty is allowed to grow and sensor data is only requested when the uncertainty must be reduced. For example when object uncertainties overlap leading to data association issues or if the uncertainty grows to beyond a field of view. These control laws are formulated into a cost function, which is optimised in real time to task sensors. By controlling an optical telescope the system has been able to construct and maintain a catalogue of approximately 100 geostationary objects.
Evidence of Structure and Persistence in Motivational Attraction to Serial Pavlovian Cues
ERIC Educational Resources Information Center
Smedley, Elizabeth B.; Smith, Kyle S.
2018-01-01
Sign-tracking is a form of autoshaping where animals develop conditioned responding directed toward stimuli predictive of an outcome even though the outcome is not contingent on the animal's behavior. Sign-tracking behaviors are thought to arise out of the attribution of incentive salience (i.e., motivational value) to reward-predictive cues. It…
Fujisaki, Waka; Nishida, Shin'ya
2010-08-07
The human brain processes different aspects of the surrounding environment through multiple sensory modalities, and each modality can be subdivided into multiple attribute-specific channels. When the brain rebinds sensory content information ('what') across different channels, temporal coincidence ('when') along with spatial coincidence ('where') provides a critical clue. It however remains unknown whether neural mechanisms for binding synchronous attributes are specific to each attribute combination, or universal and central. In human psychophysical experiments, we examined how combinations of visual, auditory and tactile attributes affect the temporal frequency limit of synchrony-based binding. The results indicated that the upper limits of cross-attribute binding were lower than those of within-attribute binding, and surprisingly similar for any combination of visual, auditory and tactile attributes (2-3 Hz). They are unlikely to be the limits for judging synchrony, since the temporal limit of a cross-attribute synchrony judgement was higher and varied with the modality combination (4-9 Hz). These findings suggest that cross-attribute temporal binding is mediated by a slow central process that combines separately processed 'what' and 'when' properties of a single event. While the synchrony performance reflects temporal bottlenecks existing in 'when' processing, the binding performance reflects the central temporal limit of integrating 'when' and 'what' properties.
49 CFR 213.365 - Visual inspections.
Code of Federal Regulations, 2011 CFR
2011-10-01
... made on foot or by riding over the track in a vehicle at a speed that allows the person making the... over track crossings and turnouts, otherwise, the inspection vehicle speed shall be at the sole... unobstructed by any cause and that the second track is not centered more than 30 feet from the track upon which...
49 CFR 213.365 - Visual inspections.
Code of Federal Regulations, 2010 CFR
2010-10-01
... made on foot or by riding over the track in a vehicle at a speed that allows the person making the... over track crossings and turnouts, otherwise, the inspection vehicle speed shall be at the sole... unobstructed by any cause and that the second track is not centered more than 30 feet from the track upon which...
NucliTrack: an integrated nuclei tracking application
Cooper, Sam; Barr, Alexis R.; Glen, Robert; Bakal, Chris
2017-01-01
Abstract Summary 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. Availability and implementation 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. Contact sam@socooper.com Supplementary information Supplementary data are available at Bioinformatics online. PMID:28637183
Bridge No. 1601, Third B&O Crossing, over CSX tracks in ...
Bridge No. 1601, Third B&O Crossing, over CSX tracks in North Branch, Maryland, looking northwest. The Pittsburgh Plate Glass Plant can be seen in the background. NPS property boundary is out of view at lower right. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD
Object attributes combine additively in visual search.
Pramod, R T; Arun, S P
2016-01-01
We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes.
Attention to Attributes and Objects in Working Memory
Cowan, Nelson; Blume, Christopher L.; Saults, J. Scott
2013-01-01
It has been debated on the basis of change-detection procedures whether visual working memory is limited by the number of objects, task-relevant attributes within those objects, or bindings between attributes. This debate, however, has been hampered by several limitations, including the use of conditions that vary between studies and the absence of appropriate mathematical models to estimate the number of items in working memory in different stimulus conditions. We re-examined working memory limits in two experiments with a wide array of conditions involving color and shape attributes, relying on a set of new models to fit various stimulus situations. In Experiment 2, a new procedure allowed identical retrieval conditions across different conditions of attention at encoding. The results show that multiple attributes compete for attention, but that retaining the binding between attributes is accomplished only by retaining the attributes themselves. We propose a theoretical account in which a fixed object capacity limit contains within it the possibility of the incomplete retention of object attributes, depending on the direction of attention. PMID:22905929
Nonstationary EO/IR Clutter Suppression and Dim Object Tracking
2010-01-01
Brown, A., and Brown, J., Enhanced Algorithms for EO /IR Electronic Stabilization, Clutter Suppression, and Track - Before - Detect for Multiple Low...estimation-suppression and nonlinear filtering-based multiple-object track - before - detect . These algorithms are suitable for integration into...In such cases, it is imperative to develop efficient real or near-real time tracking before detection methods. This paper continues the work started
Performance Analysis of Sensor Systems for Space Situational Awareness
NASA Astrophysics Data System (ADS)
Choi, Eun-Jung; Cho, Sungki; Jo, Jung Hyun; Park, Jang-Hyun; Chung, Taejin; Park, Jaewoo; Jeon, Hocheol; Yun, Ami; Lee, Yonghui
2017-12-01
With increased human activity in space, the risk of re-entry and collision between space objects is constantly increasing. Hence, the need for space situational awareness (SSA) programs has been acknowledged by many experienced space agencies. Optical and radar sensors, which enable the surveillance and tracking of space objects, are the most important technical components of SSA systems. In particular, combinations of radar systems and optical sensor networks play an outstanding role in SSA programs. At present, Korea operates the optical wide field patrol network (OWL-Net), the only optical system for tracking space objects. However, due to their dependence on weather conditions and observation time, it is not reasonable to use optical systems alone for SSA initiatives, as they have limited operational availability. Therefore, the strategies for developing radar systems should be considered for an efficient SSA system using currently available technology. The purpose of this paper is to analyze the performance of a radar system in detecting and tracking space objects. With the radar system investigated, the minimum sensitivity is defined as detection of a 1-m2 radar cross section (RCS) at an altitude of 2,000 km, with operating frequencies in the L, S, C, X or Ku-band. The results of power budget analysis showed that the maximum detection range of 2,000 km, which includes the low earth orbit (LEO) environment, can be achieved with a transmission power of 900 kW, transmit and receive antenna gains of 40 dB and 43 dB, respectively, a pulse width of 2 ms, and a signal processing gain of 13.3 dB, at a frequency of 1.3 GHz. We defined the key parameters of the radar following a performance analysis of the system. This research can thus provide guidelines for the conceptual design of radar systems for national SSA initiatives.
Determining root correspondence between previously and newly detected objects
Paglieroni, David W.; Beer, N Reginald
2014-06-17
A system that applies attribute and topology based change detection to networks of objects that were detected on previous scans of a structure, roadway, or area of interest. The attributes capture properties or characteristics of the previously detected objects, such as location, time of detection, size, elongation, orientation, etc. The topology of the network of previously detected objects is maintained in a constellation database that stores attributes of previously detected objects and implicitly captures the geometrical structure of the network. A change detection system detects change by comparing the attributes and topology of new objects detected on the latest scan to the constellation database of previously detected objects.
Nursing Training in the Brazilian Red Cross in the 1940s: a Foucaultian approach.
Mecone, Márcia Cristina da Cruz; Freitas, Genival Fernandes de; Bonini, Bárbara Barrionuevo
2015-12-01
Objectives To identify and analyze the discursive statements that characterizes the training of human resources in nursing in the 1940s by the Brazilian Red Cross. Method The approach of the documentary sources was through the assumptions of the Historical Method and they were questioned by using the thought of Michel Foucault. Results Historically, a peculiar model, the military teaching model, influenced the training of human resources in nursing, especially in the 1940s. The Brazilian Red Cross was linked to the Ministry of War and its nursing education had an emphasis on moral conduct, discipline, and respect for hierarchy, culminating in the production of nurses' "docile bodies". The attributes expected of nurses constituted the triad in the professional formation identity at that time: dedication, discipline and obedience. Conclusion The military model still reverberates practices in training of nurses in the present, as in the management, care and education in nursing.
A mathematical model for computer image tracking.
Legters, G R; Young, T Y
1982-06-01
A mathematical model using an operator formulation for a moving object in a sequence of images is presented. Time-varying translation and rotation operators are derived to describe the motion. A variational estimation algorithm is developed to track the dynamic parameters of the operators. The occlusion problem is alleviated by using a predictive Kalman filter to keep the tracking on course during severe occlusion. The tracking algorithm (variational estimation in conjunction with Kalman filter) is implemented to track moving objects with occasional occlusion in computer-simulated binary images.
Fall attributions among middle-aged and older adults with multiple sclerosis.
Peterson, Elizabeth W; Ben Ari, Eynat; Asano, Miho; Finlayson, Marcia L
2013-05-01
To (1) explore the falls attributions of middle-aged and older adults with multiple sclerosis (MS); and (2) examine the personal, health, and MS-related factors associated with the 3 most common attributions. A cross-sectional, descriptive study using data collected through a telephone interview. Falls attributions were obtained through an open-ended question to elicit participants' stories about their most recent fall. Recruitment was done through a national volunteer MS registry. Community. People (N=354) who were ≥55 years of age were interviewed; 313 provided a falls story. Respondents were primarily married, community-dwelling women who had been living with MS for 21 years, on average. Not applicable. The 3 most common fall attributions were used as dependent variables to address the second research objective. A total of 14 falls attributions were identified. The most common were balance (41.5%), lower extremity malfunction (31%), and assistive technology (AT; 29.7%). Falls control was significantly associated with the balance attribution (odds ratio [OR]=.51; 95% confidence interval [CI], .29-.88), no variables were associated with lower extremity malfunction attribution, and use of multiple mobility devices was significantly associated with the AT attribution (OR=3.78; 95% CI, 2.09-6.85). Findings highlight the complex nature of falls among middle-aged and older adults with MS and point to the need for comprehensive fall prevention interventions for this population. Further investigation of the role that perceived control over falls plays in this population is warranted. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Xing, Junliang; Ai, Haizhou; Liu, Liwei; Lao, Shihong
2011-06-01
Multiple object tracking (MOT) is a very challenging task yet of fundamental importance for many practical applications. In this paper, we focus on the problem of tracking multiple players in sports video which is even more difficult due to the abrupt movements of players and their complex interactions. To handle the difficulties in this problem, we present a new MOT algorithm which contributes both in the observation modeling level and in the tracking strategy level. For the observation modeling, we develop a progressive observation modeling process that is able to provide strong tracking observations and greatly facilitate the tracking task. For the tracking strategy, we propose a dual-mode two-way Bayesian inference approach which dynamically switches between an offline general model and an online dedicated model to deal with single isolated object tracking and multiple occluded object tracking integrally by forward filtering and backward smoothing. Extensive experiments on different kinds of sports videos, including football, basketball, as well as hockey, demonstrate the effectiveness and efficiency of the proposed method.
A Constrained and Versioned Data Model for TEAM Data
NASA Astrophysics Data System (ADS)
Andelman, S.; Baru, C.; Chandra, S.; Fegraus, E.; Lin, K.
2009-04-01
The objective of the Tropical Ecology Assessment and Monitoring Network (www.teamnetwork.org) is "To generate real time data for monitoring long-term trends in tropical biodiversity through a global network of TEAM sites (i.e. field stations in tropical forests), providing an early warning system on the status of biodiversity to effectively guide conservation action". To achieve this, the TEAM Network operates by collecting data via standardized protocols at TEAM Sites. The standardized TEAM protocols include the Climate, Vegetation and Terrestrial Vertebrate Protocols. Some sites also implement additional protocols. There are currently 7 TEAM Sites with plans to grow the network to 15 by June 30, 2009 and 50 TEAM Sites by the end of 2010. At each TEAM Site, data is gathered as defined by the protocols and according to a predefined sampling schedule. The TEAM data is organized and stored in a database based on the TEAM spatio-temporal data model. This data model is at the core of the TEAM Information System - it consumes and executes spatio-temporal queries, and analytical functions that are performed on TEAM data, and defines the object data types, relationships and operations that maintain database integrity. The TEAM data model contains object types including types for observation objects (e.g. bird, butterfly and trees), sampling unit, person, role, protocol, site and the relationship of these object types. Each observation data record is a set of attribute values of an observation object and is always associated with a sampling unit, an observation timestamp or time interval, a versioned protocol and data collectors. The operations on the TEAM data model can be classified as read operations, insert operations and update operations. Following are some typical operations: The operation get(site, protocol, [sampling unit block, sampling unit,] start time, end time) returns all data records using the specified protocol and collected at the specified site, block, sampling unit and time range. The operation insertSamplingUnit(sampling unit, site, protocol) saves a new sampling unit into the data model and links it with the site and protocol. The operation updateSampligUnit(sampling_unit_id, attribute, value) changes the attribute (e.g. latitude or longitude) of the sampling unit to the specified value. The operation insertData(observation record, site, protocol, sampling unit, timestamps, data collectors) saves a new observation record into the database and associates it with specified objects. The operation updateData(protocol, data_id, attribute, value) modifies the attribute of an existing observation record to the specified value. All the insert or update operations require: 1) authorization to ensure the user has necessary privileges to perform the operation; 2) timestamp validation to ensure the observation timestamps are in the designated time range specified in the sampling schedule; 3) data validation to check that the data records use correct taxonomy terms and data values. No authorization is performed for get operations, but under some specific condition, a username may be required for the purpose of authentication. Along with the validations above, the TEAM data model also supports human based data validation on observed data through the Data Review subsystem to ensure data quality. The data review is implemented by adding two attributes review_tag and review_comment to each observation data record. The attribute review_tag is used by a reviewer to specify the quality of data, and the attribute review_comment is for reviewers to give more information when a problem is identified. The review_tag attribute can be populated by either the system conducting QA/QC tests or by pre-specified scientific experts. The following is the review operation, which is actually a special case of the operation updateData: The operation updateReview(protocol, data_id, judgment, comment) sets the attribute review_tag and review_comment to the specified values. By systematically tracking every step, The TEAM data model can roll back to any previous state. This is achieved by introducing a historical data container for each editable object type. When the operation updateData is applied to an object to modify its attribute, the object will be tagged with the current timestamp and the name of the user who conducts the operation, the tagged object will then be moved into the historical data container, and finally a new object will be created with the new value for the specified attribute. The diagram illustrates the architecture of the TEAM data management system. A data collector can use the Data Ingestion subsystem to load new data records into the TEAM data model. The system establishes a first level of review (i.e. meets minimum data standards via QA/QC tests). Further review is done via experts and they can verify and provide their comments on data records through the Data Review subsystem. The data editor can then address data records based on the reviewer's comments. Users can use the Data Query and Download application to find data by sites, protocols and time ranges. The Data Query and Download system packages selected data with the data license and important metadata information into a single package and delivers it to the user.
Singh, Niharika; Mishra, Ramesh Kumar
2015-01-01
Using a variant of the visual world eye tracking paradigm, we examined if language non- selective activation of translation equivalents leads to attention capture and distraction in a visual task in bilinguals. High and low proficient Hindi-English speaking bilinguals were instructed to programme a saccade towards a line drawing which changed colour among other distractor objects. A spoken word, irrelevant to the main task, was presented before the colour change. On critical trials, one of the line drawings was a phonologically related word of the translation equivalent of the spoken word. Results showed that saccade latency was significantly higher towards the target in the presence of this cross-linguistic translation competitor compared to when the display contained completely unrelated objects. Participants were also slower when the display contained the referent of the spoken word among the distractors. However, the bilingual groups did not differ with regard to the interference effect observed. These findings suggest that spoken words activates translation equivalent which bias attention leading to interference in goal directed action in the visual domain. PMID:25775184
Object tracking using multiple camera video streams
NASA Astrophysics Data System (ADS)
Mehrubeoglu, Mehrube; Rojas, Diego; McLauchlan, Lifford
2010-05-01
Two synchronized cameras are utilized to obtain independent video streams to detect moving objects from two different viewing angles. The video frames are directly correlated in time. Moving objects in image frames from the two cameras are identified and tagged for tracking. One advantage of such a system involves overcoming effects of occlusions that could result in an object in partial or full view in one camera, when the same object is fully visible in another camera. Object registration is achieved by determining the location of common features in the moving object across simultaneous frames. Perspective differences are adjusted. Combining information from images from multiple cameras increases robustness of the tracking process. Motion tracking is achieved by determining anomalies caused by the objects' movement across frames in time in each and the combined video information. The path of each object is determined heuristically. Accuracy of detection is dependent on the speed of the object as well as variations in direction of motion. Fast cameras increase accuracy but limit the speed and complexity of the algorithm. Such an imaging system has applications in traffic analysis, surveillance and security, as well as object modeling from multi-view images. The system can easily be expanded by increasing the number of cameras such that there is an overlap between the scenes from at least two cameras in proximity. An object can then be tracked long distances or across multiple cameras continuously, applicable, for example, in wireless sensor networks for surveillance or navigation.
Observational Word Learning: Beyond Propose-But-Verify and Associative Bean Counting.
Roembke, Tanja; McMurray, Bob
2016-04-01
Learning new words is difficult. In any naming situation, there are multiple possible interpretations of a novel word. Recent approaches suggest that learners may solve this problem by tracking co-occurrence statistics between words and referents across multiple naming situations (e.g. Yu & Smith, 2007), overcoming the ambiguity in any one situation. Yet, there remains debate around the underlying mechanisms. We conducted two experiments in which learners acquired eight word-object mappings using cross-situational statistics while eye-movements were tracked. These addressed four unresolved questions regarding the learning mechanism. First, eye-movements during learning showed evidence that listeners maintain multiple hypotheses for a given word and bring them all to bear in the moment of naming. Second, trial-by-trial analyses of accuracy suggested that listeners accumulate continuous statistics about word/object mappings, over and above prior hypotheses they have about a word. Third, consistent, probabilistic context can impede learning, as false associations between words and highly co-occurring referents are formed. Finally, a number of factors not previously considered in prior analysis impact observational word learning: knowledge of the foils, spatial consistency of the target object, and the number of trials between presentations of the same word. This evidence suggests that observational word learning may derive from a combination of gradual statistical or associative learning mechanisms and more rapid real-time processes such as competition, mutual exclusivity and even inference or hypothesis testing.
Park, Jae Hyeon; Sut, Tun Naw; Jackman, Joshua A; Ferhan, Abdul Rahim; Yoon, Bo Kyeong; Cho, Nam-Joon
2017-03-29
Understanding the physicochemical factors that influence protein adsorption onto solid supports holds wide relevance for fundamental insights into protein structure and function as well as for applications such as surface passivation. Ionic strength is a key parameter that influences protein adsorption, although how its modulation might be utilized to prepare well-coated protein adlayers remains to be explored. Herein, we investigated how ionic strength can be utilized to control the adsorption and passivation properties of bovine serum albumin (BSA) on silica surfaces. As protein stability in solution can influence adsorption kinetics, the size distribution and secondary structure of proteins in solution were first characterized by dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), and circular dichroism (CD) spectroscopy. A non-monotonic correlation between ionic strength and protein aggregation was observed and attributed to colloidal agglomeration, while the primarily α-helical character of the protein in solution was maintained in all cases. Quartz crystal microbalance-dissipation (QCM-D) experiments were then conducted in order to track protein adsorption onto silica surfaces as a function of ionic strength, and the measurement responses indicated that total protein uptake at saturation coverage is lower with increasing ionic strength. In turn, the QCM-D data and the corresponding Voigt-Voinova model analysis support that the surface area per bound protein molecule is greater with increasing ionic strength. While higher protein uptake under lower ionic strengths by itself did not result in greater surface passivation under subsequent physiologically relevant conditions, the treatment of adsorbed protein layers with a gluteraldehyde cross-linking agent stabilized the bound protein in this case and significantly improved surface passivation. Collectively, our findings demonstrate that ionic strength modulation influences BSA adsorption uptake on account of protein spreading and can be utilized in conjunction with covalent cross-linking strategies to prepare well-coated protein adlayers for improved surface passivation.
Early conversational environment enables spontaneous belief attribution in deaf children.
Meristo, Marek; Strid, Karin; Hjelmquist, Erland
2016-12-01
Previous research suggests that deaf children who grow up with hearing parents display considerable difficulties in understanding mental states of others, up to their teenage years when explicitly asked in a verbal test situation (Meristo et al., 2007). On the other hand, typically developing pre-verbal infants display evidence of spontaneous false belief attribution when tested in looking-time tasks, although verbal tests are typically not passed before the age of 4years (Onishi & Baillargeon, 2005). The purpose of the present study was to examine whether deaf children of hearing parents are able to demonstrate spontaneous belief attribution in a non-verbal eye-tracking task. Thirty 4- to 8-year-old, deaf and hearing children, completed a non-verbal spontaneous-response false-belief task and a verbal elicited-response false-belief task. The deaf children were either children with cochlear implants or children with hearing aids. Comparative analyses were also carried out with a previous sample of deaf and hearing 2-year-olds (reported in Meristo, Morgan, et al., 2012). We found that in the non-verbal spontaneous-response task typically hearing children, but not deaf children, were able to predict that a person with a false belief about an object's location will search erroneously for the object. However, hearing children and deaf children with implants, but not deaf children with hearing aids, passed the verbal elicited-response task. Language development was significantly correlated with both types of false-belief tasks for the whole sample. Our findings strengthen the hypothesis that the emergence of the ability to recognize others' beliefs needs to be supported initially by very early conversational input in dialogues with caregivers. Copyright © 2016 Elsevier B.V. All rights reserved.
Electrically tunable lens speeds up 3D orbital tracking
Annibale, Paolo; Dvornikov, Alexander; Gratton, Enrico
2015-01-01
3D orbital particle tracking is a versatile and effective microscopy technique that allows following fast moving fluorescent objects within living cells and reconstructing complex 3D shapes using laser scanning microscopes. We demonstrated notable improvements in the range, speed and accuracy of 3D orbital particle tracking by replacing commonly used piezoelectric stages with Electrically Tunable Lens (ETL) that eliminates mechanical movement of objective lenses. This allowed tracking and reconstructing shape of structures extending 500 microns in the axial direction. Using the ETL, we tracked at high speed fluorescently labeled genomic loci within the nucleus of living cells with unprecedented temporal resolution of 8ms using a 1.42NA oil-immersion objective. The presented technology is cost effective and allows easy upgrade of scanning microscopes for fast 3D orbital tracking. PMID:26114037
Tracking Algorithm of Multiple Pedestrians Based on Particle Filters in Video Sequences
Liu, Yun; Wang, Chuanxu; Zhang, Shujun; Cui, Xuehong
2016-01-01
Pedestrian tracking is a critical problem in the field of computer vision. Particle filters have been proven to be very useful in pedestrian tracking for nonlinear and non-Gaussian estimation problems. However, pedestrian tracking in complex environment is still facing many problems due to changes of pedestrian postures and scale, moving background, mutual occlusion, and presence of pedestrian. To surmount these difficulties, this paper presents tracking algorithm of multiple pedestrians based on particle filters in video sequences. The algorithm acquires confidence value of the object and the background through extracting a priori knowledge thus to achieve multipedestrian detection; it adopts color and texture features into particle filter to get better observation results and then automatically adjusts weight value of each feature according to current tracking environment. During the process of tracking, the algorithm processes severe occlusion condition to prevent drift and loss phenomena caused by object occlusion and associates detection results with particle state to propose discriminated method for object disappearance and emergence thus to achieve robust tracking of multiple pedestrians. Experimental verification and analysis in video sequences demonstrate that proposed algorithm improves the tracking performance and has better tracking results. PMID:27847514
Fagan, C C; O'Donnell, C P; O'Callaghan, D J; Downey, G; Sheehan, E M; Delahunty, C M; Everard, C; Guinee, T P; Howard, V
2007-04-01
The objective of this study was to determine the potential of mid-infrared spectroscopy in conjunction with partial least squares (PLS) regression to predict various quality parameters in cheddar cheese. Cheddar cheeses (n= 24) were manufactured and stored at 8 degrees C for 12 mo. Mid-infrared spectra (640 to 4000/cm) were recorded after 4, 6, 9, and 12 mo storage. At 4, 6, and 9 mo, the water-soluble nitrogen (WSN) content of the samples was determined and the samples were also evaluated for 11 sensory texture attributes using descriptive sensory analysis. The mid-infrared spectra were subjected to a number of pretreatments, and predictive models were developed for all parameters. Age was predicted using scatter-corrected, 1st derivative spectra with a root mean square error of cross-validation (RMSECV) of 1 mo, while WSN was predicted using 1st derivative spectra (RMSECV = 2.6%). The sensory texture attributes most successfully predicted were rubbery, crumbly, chewy, and massforming. These attributes were modeled using 2nd derivative spectra and had corresponding RMSECV values in the range of 2.5 to 4.2 on a scale of 0 to 100. It was concluded that mid-infrared spectroscopy has the potential to predict age, WSN, and several sensory texture attributes of cheddar cheese.
Cheng, Ashley
2014-01-01
Objective Describe the epidemiologic literature related to early-life feeding practices and early childhood caries (ECC) with regard to publication attributes and trends in these attributes over time. Methods Systematic literature review including electronic and manual searches (in BIOSIS, CINAHL, Cochrane Library, LILACS, MEDLINE, Web of Science, and WHOLIS), covering the years 1990–2013. Attributes of publications meeting a priori inclusion criteria were abstracted and organized by global region and trends over time. Attributes included country of origin and study design of included publications and age and caries prevalence of the populations studied. Results 244 publications drawn from 196 independent study populations were included. The number of publications and the countries represented increased over time, although some world regions remained underrepresented. Most publications were cross sectional (75%); while this percentage remained fairly constant over time, the percentage of studies to account for confounding factors increased. Publications varied with respect to the caries experience and age range of children included in each study. Conclusions Publication productivity regarding feeding practices and ECC research has grown, but this growth has not been evenly distributed globally. Individual publication attributes (i.e. methods and context) can differ significantly and should be considered when interpreting and synthesizing the literature. PMID:25328911
Attributions and self-efficacy for physical activity in multiple sclerosis.
Nickel, D; Spink, K; Andersen, M; Knox, K
2014-01-01
Self-efficacy is an important predictor of health-related physical activity in multiple sclerosis (MS). While past experiences are believed to influence efficacy beliefs, the explanations individuals provide for these experiences also may be critical. Our objective was to test the hypothesis that perceived success or failure to accumulate 150 min of physical activity in the previous week would moderate the relationship between the attributional dimension of stability and self-efficacy to exercise in the future. Forty-two adults with MS participated in this cross-sectional descriptive study. Participants completed questions assessing physical activity, perceived outcome for meeting the recommended level of endurance activity, attributions for the outcome, and exercise self-efficacy. Results from hierarchical multiple regression revealed a significant main effect for perceived outcome predicting self-efficacy that was qualified by a significant interaction. The final model, which included perceived outcome, stability, and the interaction term, predicted 37% of the variance in exercise self-efficacy, F (3, 38) = 7.27, p = .001. Our findings suggest that the best prediction of self-efficacy in the MS population may include the interaction of specific attributional dimensions with success/failure at meeting the recommended physical activity dose. Attributions may be another target for interventions aimed at increasing the physical activity in MS.
Sempere, Angel Perez; Vera-Lopez, Vanesa; Gimenez-Martinez, Juana; Ruiz-Beato, Elena; Cuervo, Jesús; Maurino, Jorge
2017-01-01
Purpose Multidimensional unfolding is a multivariate method to assess preferences using a small sample size, a geometric model locating individuals and alternatives as points in a joint space. The objective was to evaluate relapsing–remitting multiple sclerosis (RRMS) patient preferences toward key disease-modifying therapy (DMT) attributes using multidimensional unfolding. Patients and methods A cross-sectional pilot study in RRMS patients was conducted. Drug attributes included relapse prevention, disease progression prevention, side-effect risk and route and schedule of administration. Assessment of preferences was performed through a five-card game. Patients were asked to value attributes from 1 (most preferred) to 5 (least preferred). Results A total of 37 patients were included; the mean age was 38.6 years, and 78.4% were female. Disease progression prevention was the most important factor (51.4%), followed by relapse prevention (40.5%). The frequency of administration had the lowest preference rating for 56.8% of patients. Finally, 19.6% valued the side-effect risk attribute as having low/very low importance. Conclusion Patients’ perspective for DMT attributes may provide valuable information to facilitate shared decision-making. Efficacy attributes were the most important drug characteristics for RRMS patients. Multidimensional unfolding seems to be a feasible approach to assess preferences in multiple sclerosis patients. Further elicitation studies using multidimensional unfolding with other stated choice methods are necessary to confirm these findings. PMID:28615928
Hu, Weiming; Gao, Jin; Xing, Junliang; Zhang, Chao; Maybank, Stephen
2017-01-01
An appearance model adaptable to changes in object appearance is critical in visual object tracking. In this paper, we treat an image patch as a two-order tensor which preserves the original image structure. We design two graphs for characterizing the intrinsic local geometrical structure of the tensor samples of the object and the background. Graph embedding is used to reduce the dimensions of the tensors while preserving the structure of the graphs. Then, a discriminant embedding space is constructed. We prove two propositions for finding the transformation matrices which are used to map the original tensor samples to the tensor-based graph embedding space. In order to encode more discriminant information in the embedding space, we propose a transfer-learning- based semi-supervised strategy to iteratively adjust the embedding space into which discriminative information obtained from earlier times is transferred. We apply the proposed semi-supervised tensor-based graph embedding learning algorithm to visual tracking. The new tracking algorithm captures an object's appearance characteristics during tracking and uses a particle filter to estimate the optimal object state. Experimental results on the CVPR 2013 benchmark dataset demonstrate the effectiveness of the proposed tracking algorithm.
NASA Astrophysics Data System (ADS)
Li, Shengbo Eben; Li, Guofa; Yu, Jiaying; Liu, Chang; Cheng, Bo; Wang, Jianqiang; Li, Keqiang
2018-01-01
Detection and tracking of objects in the side-near-field has attracted much attention for the development of advanced driver assistance systems. This paper presents a cost-effective approach to track moving objects around vehicles using linearly arrayed ultrasonic sensors. To understand the detection characteristics of a single sensor, an empirical detection model was developed considering the shapes and surface materials of various detected objects. Eight sensors were arrayed linearly to expand the detection range for further application in traffic environment recognition. Two types of tracking algorithms, including an Extended Kalman filter (EKF) and an Unscented Kalman filter (UKF), for the sensor array were designed for dynamic object tracking. The ultrasonic sensor array was designed to have two types of fire sequences: mutual firing or serial firing. The effectiveness of the designed algorithms were verified in two typical driving scenarios: passing intersections with traffic sign poles or street lights, and overtaking another vehicle. Experimental results showed that both EKF and UKF had more precise tracking position and smaller RMSE (root mean square error) than a traditional triangular positioning method. The effectiveness also encourages the application of cost-effective ultrasonic sensors in the near-field environment perception in autonomous driving systems.
Multiple-Object Tracking in Children: The "Catch the Spies" Task
ERIC Educational Resources Information Center
Trick, L.M.; Jaspers-Fayer, F.; Sethi, N.
2005-01-01
Multiple-object tracking involves simultaneously tracking positions of a number of target-items as they move among distractors. The standard version of the task poses special challenges for children, demanding extended concentration and the ability to distinguish targets from identical-looking distractors, and may thus underestimate children's…
Vehicle and cargo container inspection system for drugs
NASA Astrophysics Data System (ADS)
Verbinski, Victor V.; Orphan, Victor J.
1999-06-01
A vehicle and cargo container inspection system has been developed which uses gamma-ray radiography to produce digital images useful for detection of drugs and other contraband. The system is comprised of a 1 Ci Cs137 gamma-ray source collimated into a fan beam which is aligned with a linear array of NaI gamma-ray detectors located on the opposite side of the container. The NaI detectors are operated in the pulse-counting mode. A digital image of the vehicle or container is obtained by moving the aligned source and detector array relative to the object. Systems have been demonstrated in which the object is stationary (source and detector array move on parallel tracks) and in which the object moves past a stationary source and detector array. Scanning speeds of ˜30 cm/s with a pixel size (at the object) of ˜1 cm have been achieved. Faster scanning speeds of ˜2 m/s have been demonstrated on railcars with more modest spatial resolution (4 cm pixels). Digital radiographic images are generated from the detector count rates. These images, recorded on a PC-based data acquisition and display system, are shown from several applications: 1) inspection of trucks and containers at a border crossing, 2) inspection of railcars at a border crossing, 3) inspection of outbound cargo containers for stolen automobiles, and 4) inspection of trucks and cars for terrorist bombs.
Long-term object tracking combined offline with online learning
NASA Astrophysics Data System (ADS)
Hu, Mengjie; Wei, Zhenzhong; Zhang, Guangjun
2016-04-01
We propose a simple yet effective method for long-term object tracking. Different from the traditional visual tracking method, which mainly depends on frame-to-frame correspondence, we combine high-level semantic information with low-level correspondences. Our framework is formulated in a confidence selection framework, which allows our system to recover from drift and partly deal with occlusion. To summarize, our algorithm can be roughly decomposed into an initialization stage and a tracking stage. In the initialization stage, an offline detector is trained to get the object appearance information at the category level, which is used for detecting the potential target and initializing the tracking stage. The tracking stage consists of three modules: the online tracking module, detection module, and decision module. A pretrained detector is used for maintaining drift of the online tracker, while the online tracker is used for filtering out false positive detections. A confidence selection mechanism is proposed to optimize the object location based on the online tracker and detection. If the target is lost, the pretrained detector is utilized to reinitialize the whole algorithm when the target is relocated. During experiments, we evaluate our method on several challenging video sequences, and it demonstrates huge improvement compared with detection and online tracking only.
Object attributes combine additively in visual search
Pramod, R. T.; Arun, S. P.
2016-01-01
We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes. PMID:26967014
Improved semi-supervised online boosting for object tracking
NASA Astrophysics Data System (ADS)
Li, Yicui; Qi, Lin; Tan, Shukun
2016-10-01
The advantage of an online semi-supervised boosting method which takes object tracking problem as a classification problem, is training a binary classifier from labeled and unlabeled examples. Appropriate object features are selected based on real time changes in the object. However, the online semi-supervised boosting method faces one key problem: The traditional self-training using the classification results to update the classifier itself, often leads to drifting or tracking failure, due to the accumulated error during each update of the tracker. To overcome the disadvantages of semi-supervised online boosting based on object tracking methods, the contribution of this paper is an improved online semi-supervised boosting method, in which the learning process is guided by positive (P) and negative (N) constraints, termed P-N constraints, which restrict the labeling of the unlabeled samples. First, we train the classification by an online semi-supervised boosting. Then, this classification is used to process the next frame. Finally, the classification is analyzed by the P-N constraints, which are used to verify if the labels of unlabeled data assigned by the classifier are in line with the assumptions made about positive and negative samples. The proposed algorithm can effectively improve the discriminative ability of the classifier and significantly alleviate the drifting problem in tracking applications. In the experiments, we demonstrate real-time tracking of our tracker on several challenging test sequences where our tracker outperforms other related on-line tracking methods and achieves promising tracking performance.
ERIC Educational Resources Information Center
Kärki, Tomi; Keinänen, Heli; Tuominen, Anu; Hoikkala, Marianna; Matikainen, Eila; Maijala, Hanna
2018-01-01
The authors consider the use of mobile learning environment ActionTrack in teacher education. Pre-service class teachers' (N = 277) experiences of the mobile learning environment were measured with a 7-point Likert-scale questionnaire based on seven attributes of meaningful learning. Students' ratings for different attributes were analysed…
Attention, Exposure Duration, and Gaze Shifting in Naming Performance
ERIC Educational Resources Information Center
Roelofs, Ardi
2011-01-01
Two experiments are reported in which the role of attribute exposure duration in naming performance was examined by tracking eye movements. Participants were presented with color-word Stroop stimuli and left- or right-pointing arrows on different sides of a computer screen. They named the color attribute and shifted their gaze to the arrow to…
The Inter-Sectoral Impact Model Intercomparison Project (ISI–MIP): Project framework
Warszawski, Lila; Frieler, Katja; Huber, Veronika; Piontek, Franziska; Serdeczny, Olivia; Schewe, Jacob
2014-01-01
The Inter-Sectoral Impact Model Intercomparison Project offers a framework to compare climate impact projections in different sectors and at different scales. Consistent climate and socio-economic input data provide the basis for a cross-sectoral integration of impact projections. The project is designed to enable quantitative synthesis of climate change impacts at different levels of global warming. This report briefly outlines the objectives and framework of the first, fast-tracked phase of Inter-Sectoral Impact Model Intercomparison Project, based on global impact models, and provides an overview of the participating models, input data, and scenario set-up. PMID:24344316
NASA Astrophysics Data System (ADS)
Fan, Li; Jiang, Chao; Hu, Min
2017-02-01
Eight inclined geosynchronous satellite orbit (IGSO) satellites in the Chinese BeiDou Navigation Satellite System (BDS) have been put in orbit until now. IGSO is a special class of geosynchronous circular orbit, with the inclination not equal to zero. It can provide high elevation angle coverage to high-latitude areas. The geography longitude of the ground track cross node is the main factor to affect the ground coverage areas of the IGSO satellites. In order to ensure the navigation performance of the IGSO satellites, the maintenance control of the ground track cross node is required. Considering the tesseral resonances and the luni-solar perturbations, a control approach is proposed to maintain the ground track for the long-term evolution. The drifts of the ground track cross node of the IGSO satellites are analyzed, which is formulated as a function of the bias of the orbit elements and time. Based on the derived function, a method by offsetting the semi-major axis is put forward to maintain the longitude of the ground track cross node, and the offset calculation equation is presented as well. Moreover, the orbit inclination is adjusted to maintain the location angle intervals between each two IGSO satellites. Finally, the precision of the offset calculation equation is analyzed to achieve the operational deployment. Simulation results show that the semi-major axis offset method is effective, and its calculation equation is accurate. The proposed approach has been applied to the maintenance control of BeiDou IGSO satellites.
Mark Tracking: Position/orientation measurements using 4-circle mark and its tracking experiments
NASA Technical Reports Server (NTRS)
Kanda, Shinji; Okabayashi, Keijyu; Maruyama, Tsugito; Uchiyama, Takashi
1994-01-01
Future space robots require position and orientation tracking with visual feedback control to track and capture floating objects and satellites. We developed a four-circle mark that is useful for this purpose. With this mark, four geometric center positions as feature points can be extracted from the mark by simple image processing. We also developed a position and orientation measurement method that uses the four feature points in our mark. The mark gave good enough image measurement accuracy to let space robots approach and contact objects. A visual feedback control system using this mark enabled a robot arm to track a target object accurately. The control system was able to tolerate a time delay of 2 seconds.
Multiple object tracking using the shortest path faster association algorithm.
Xi, Zhenghao; Liu, Heping; Liu, Huaping; Yang, Bin
2014-01-01
To solve the persistently multiple object tracking in cluttered environments, this paper presents a novel tracking association approach based on the shortest path faster algorithm. First, the multiple object tracking is formulated as an integer programming problem of the flow network. Then we relax the integer programming to a standard linear programming problem. Therefore, the global optimum can be quickly obtained using the shortest path faster algorithm. The proposed method avoids the difficulties of integer programming, and it has a lower worst-case complexity than competing methods but better robustness and tracking accuracy in complex environments. Simulation results show that the proposed algorithm takes less time than other state-of-the-art methods and can operate in real time.
Compressed multi-block local binary pattern for object tracking
NASA Astrophysics Data System (ADS)
Li, Tianwen; Gao, Yun; Zhao, Lei; Zhou, Hao
2018-04-01
Both robustness and real-time are very important for the application of object tracking under a real environment. The focused trackers based on deep learning are difficult to satisfy with the real-time of tracking. Compressive sensing provided a technical support for real-time tracking. In this paper, an object can be tracked via a multi-block local binary pattern feature. The feature vector was extracted based on the multi-block local binary pattern feature, which was compressed via a sparse random Gaussian matrix as the measurement matrix. The experiments showed that the proposed tracker ran in real-time and outperformed the existed compressive trackers based on Haar-like feature on many challenging video sequences in terms of accuracy and robustness.
Multiple Object Tracking Using the Shortest Path Faster Association Algorithm
Liu, Heping; Liu, Huaping; Yang, Bin
2014-01-01
To solve the persistently multiple object tracking in cluttered environments, this paper presents a novel tracking association approach based on the shortest path faster algorithm. First, the multiple object tracking is formulated as an integer programming problem of the flow network. Then we relax the integer programming to a standard linear programming problem. Therefore, the global optimum can be quickly obtained using the shortest path faster algorithm. The proposed method avoids the difficulties of integer programming, and it has a lower worst-case complexity than competing methods but better robustness and tracking accuracy in complex environments. Simulation results show that the proposed algorithm takes less time than other state-of-the-art methods and can operate in real time. PMID:25215322
Highway-railway at-grade crossing structures : long term settlement measurements and assessments.
DOT National Transportation Integrated Search
2016-03-22
A common maintenance technique to correct track geometry at bridge transitions is hand tamping. The first section presents a non-invasive track monitoring system involving high-speed video cameras that evaluates the change in track behavior before an...
ERIC Educational Resources Information Center
Schaffner, Ellen; Philipp, Maik; Schiefele, Ulrich
2016-01-01
Previous research has demonstrated positive relations between intrinsic reading motivation and reading competence. However, the causal direction of these relations and the moderating role of relevant background variables (e.g., students' achievement level) are not well understood. In the present study, a cross-lagged panel model was applied to…
Doublet Pulse Coherent Laser Radar for Tracking of Resident Space Objects
2014-09-01
based laser systems can be limited by the effects of tumbling, extremely accurate Doppler measurement is possible using a doublet coherent laser ...Doublet pulse coherent laser radar for tracking of resident space objects Narasimha S. Prasad *1 , Van Rudd 2 , Scott Shald 2 , Stephan...Doublet Pulse Coherent Laser Radar for Tracking of Resident Space Objects 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S
Phenomenal permanence and the development of predictive tracking in infancy.
Bertenthal, Bennett I; Longo, Matthew R; Kenny, Sarah
2007-01-01
The perceived spatiotemporal continuity of objects depends on the way they appear and disappear as they move in the spatial layout. This study investigated whether infants' predictive tracking of a briefly occluded object is sensitive to the manner by which the object disappears and reappears. Five-, 7-, and 9-month-old infants were shown a ball rolling across a visual scene and briefly disappearing via kinetic occlusion, instantaneous disappearance, implosion, or virtual occlusion. Three different measures converged to show that predictive tracking increased with age and that infants were most likely to anticipate the reappearance of the ball following kinetic occlusion. These results suggest that infants' knowledge of the permanence and nonpermanence of objects is embodied in their predictive tracking.
Robust feedback zoom tracking for digital video surveillance.
Zou, Tengyue; Tang, Xiaoqi; Song, Bao; Wang, Jin; Chen, Jihong
2012-01-01
Zoom tracking is an important function in video surveillance, particularly in traffic management and security monitoring. It involves keeping an object of interest in focus during the zoom operation. Zoom tracking is typically achieved by moving the zoom and focus motors in lenses following the so-called "trace curve", which shows the in-focus motor positions versus the zoom motor positions for a specific object distance. The main task of a zoom tracking approach is to accurately estimate the trace curve for the specified object. Because a proportional integral derivative (PID) controller has historically been considered to be the best controller in the absence of knowledge of the underlying process and its high-quality performance in motor control, in this paper, we propose a novel feedback zoom tracking (FZT) approach based on the geometric trace curve estimation and PID feedback controller. The performance of this approach is compared with existing zoom tracking methods in digital video surveillance. The real-time implementation results obtained on an actual digital video platform indicate that the developed FZT approach not only solves the traditional one-to-many mapping problem without pre-training but also improves the robustness for tracking moving or switching objects which is the key challenge in video surveillance.
Mateus, Ana Rita A; Grilo, Clara; Santos-Reis, Margarida
2011-10-01
Environmental assessment studies often evaluate the effectiveness of drainage culverts as habitat linkages for species, however, the efficiency of the sampling designs and the survey methods are not known. Our main goal was to estimate the most cost-effective monitoring method for sampling carnivore culvert using track-pads and video-surveillance. We estimated the most efficient (lower costs and high detection success) interval between visits (days) when using track-pads and also determined the advantages of using each method. In 2006, we selected two highways in southern Portugal and sampled 15 culverts over two 10-day sampling periods (spring and summer). Using the track-pad method, 90% of the animal tracks were detected using a 2-day interval between visits. We recorded a higher number of crossings for most species using video-surveillance (n = 129) when compared with the track-pad technique (n = 102); however, the detection ability using the video-surveillance method varied with type of structure and species. More crossings were detected in circular culverts (1 m and 1.5 m diameter) than in box culverts (2 m to 4 m width), likely because video cameras had a reduced vision coverage area. On the other hand, carnivore species with small feet such as the common genet Genetta genetta were detected less often using the track-pad surveying method. The cost-benefit analyzes shows that the track-pad technique is the most appropriate technique, but video-surveillance allows year-round surveys as well as the behavior response analyzes of species using crossing structures.
Direct electron-pair production by high energy heavy charged particles
NASA Technical Reports Server (NTRS)
Takahashi, Y.; Gregory, J. C.; Hayashi, T.; Dong, B. L.
1989-01-01
Direct electron pain production via virtual photons by moving charged particles is a unique electro-magnetic process having a substantial dependence on energy. Most electro-magnetic processes, including transition radiation, cease to be sensitive to the incident energy above 10 TeV/AMU. Thus, it is expected, that upon establishment of cross section and detection efficiency of this process, it may provide a new energy measuring technique above 10 TeV/AMU. Three accelerator exposures of emulsion chambers designed for measurements of direct electron-pains were performed. The objectives of the investigation were to provide the fundamental cross-section data in emulsion stacks to find the best-fit theoretical model, and to provide a calibration of measurements of direct electron-pairs in emulsion chamber configurations. This paper reports the design of the emulsion chambers, accelerator experiments, microscope measurements, and related considerations for future improvements of the measurements, and for possible applications to high energy cosmic ray experiments. Also discussed are the results from scanning 56m of emulsion tracks at 1200x magnification so that scanning efficiency is optimized. Measurements of the delta-ray range spectrum were also performed for much shorter track lengths, but with sufficiently large statistics in the number of measured delta-rays.
The track structure in condensed matter
NASA Astrophysics Data System (ADS)
Kaplan, I. G.
1995-11-01
The physical stage of track formation in a condensed phase is discussed. For interaction of charged particles with condensed molecular media its most important specific features are: (a) the continuous oscillator strength distribution with the broak peak in the energy range 21-22 eV attributed to the collective plasmon-type state; (b) the lowering of ionization potential compared to a gas phase. These specific features must be taken into account for simulation of track structures. The great difference in mass and charge for a electron and heavy ions cause a qualitative difference in their track structures. We analyse the structure of heavy ion tracks and prove the impossibility to use the LET as a universal characteristic for the radiation action of different ions.
Human emotions track changes in the acoustic environment.
Ma, Weiyi; Thompson, William Forde
2015-11-24
Emotional responses to biologically significant events are essential for human survival. Do human emotions lawfully track changes in the acoustic environment? Here we report that changes in acoustic attributes that are well known to interact with human emotions in speech and music also trigger systematic emotional responses when they occur in environmental sounds, including sounds of human actions, animal calls, machinery, or natural phenomena, such as wind and rain. Three changes in acoustic attributes known to signal emotional states in speech and music were imposed upon 24 environmental sounds. Evaluations of stimuli indicated that human emotions track such changes in environmental sounds just as they do for speech and music. Such changes not only influenced evaluations of the sounds themselves, they also affected the way accompanying facial expressions were interpreted emotionally. The findings illustrate that human emotions are highly attuned to changes in the acoustic environment, and reignite a discussion of Charles Darwin's hypothesis that speech and music originated from a common emotional signal system based on the imitation and modification of environmental sounds.
Fujisaki, Waka; Nishida, Shin'ya
2010-01-01
The human brain processes different aspects of the surrounding environment through multiple sensory modalities, and each modality can be subdivided into multiple attribute-specific channels. When the brain rebinds sensory content information (‘what’) across different channels, temporal coincidence (‘when’) along with spatial coincidence (‘where’) provides a critical clue. It however remains unknown whether neural mechanisms for binding synchronous attributes are specific to each attribute combination, or universal and central. In human psychophysical experiments, we examined how combinations of visual, auditory and tactile attributes affect the temporal frequency limit of synchrony-based binding. The results indicated that the upper limits of cross-attribute binding were lower than those of within-attribute binding, and surprisingly similar for any combination of visual, auditory and tactile attributes (2–3 Hz). They are unlikely to be the limits for judging synchrony, since the temporal limit of a cross-attribute synchrony judgement was higher and varied with the modality combination (4–9 Hz). These findings suggest that cross-attribute temporal binding is mediated by a slow central process that combines separately processed ‘what’ and ‘when’ properties of a single event. While the synchrony performance reflects temporal bottlenecks existing in ‘when’ processing, the binding performance reflects the central temporal limit of integrating ‘when’ and ‘what’ properties. PMID:20335212
A neuromorphic approach to satellite image understanding
NASA Astrophysics Data System (ADS)
Partsinevelos, Panagiotis; Perakakis, Manolis
2014-05-01
Remote sensing satellite imagery provides high altitude, top viewing aspects of large geographic regions and as such the depicted features are not always easily recognizable. Nevertheless, geoscientists familiar to remote sensing data, gradually gain experience and enhance their satellite image interpretation skills. The aim of this study is to devise a novel computational neuro-centered classification approach for feature extraction and image understanding. Object recognition through image processing practices is related to a series of known image/feature based attributes including size, shape, association, texture, etc. The objective of the study is to weight these attribute values towards the enhancement of feature recognition. The key cognitive experimentation concern is to define the point when a user recognizes a feature as it varies in terms of the above mentioned attributes and relate it with their corresponding values. Towards this end, we have set up an experimentation methodology that utilizes cognitive data from brain signals (EEG) and eye gaze data (eye tracking) of subjects watching satellite images of varying attributes; this allows the collection of rich real-time data that will be used for designing the image classifier. Since the data are already labeled by users (using an input device) a first step is to compare the performance of various machine-learning algorithms on the collected data. On the long-run, the aim of this work would be to investigate the automatic classification of unlabeled images (unsupervised learning) based purely on image attributes. The outcome of this innovative process is twofold: First, in an abundance of remote sensing image datasets we may define the essential image specifications in order to collect the appropriate data for each application and improve processing and resource efficiency. E.g. for a fault extraction application in a given scale a medium resolution 4-band image, may be more effective than costly, multispectral, very high resolution imagery. Second, we attempt to relate the experienced against the non-experienced user understanding in order to indirectly assess the possible limits of purely computational systems. In other words, obtain the conceptual limits of computation vs human cognition concerning feature recognition from satellite imagery. Preliminary results of this pilot study show relations between collected data and differentiation of the image attributes which indicates that our methodology can lead to important results.
Electromagnetic absorption properties of spacecraft and space debris
NASA Astrophysics Data System (ADS)
Micheli, D.; Santoni, F.; Giusti, A.; Delfini, A.; Pastore, R.; Vricella, A.; Albano, M.; Arena, L.; Piergentili, F.; Marchetti, M.
2017-04-01
Aim of the work is to present a method to evaluate the electromagnetic absorption properties of spacecraft and space debris. For these objects, the radar detection ability depends mainly on volume, shape, materials type and other electromagnetic reflecting behaviour of spacecraft surface components, such as antennas or thermal blankets, and of metallic components in space debris. The higher the electromagnetic reflection coefficient of such parts, the greater the radar detection possibility. In this research an electromagnetic reverberation chamber is used to measure the absorption cross section (ACS) of four objects which may represent space structure operating components as well as examples of space debris: a small satellite, a composite antenna dish, a Thermal Protection System (TPS) tile and a carbon-based composite missile shell. The ACS mainly depends on geometrical characteristics like apertures, face numbers and bulk porosity, as well as on the type of the material itself. The ACS, which is an electromagnetic measurement, is expressed in squared meters and thus can be compared with the objects geometrical cross section. A small ACS means a quite electromagnetic reflective tendency, which is beneficial for radar observations; on the contrary, high values of ACS indicate a strong absorption of the electromagnetic field, which in turn can result a critical hindering of radar tracking.
NASA Technical Reports Server (NTRS)
Dustin, M. O.
1983-01-01
A special-purpose dynamometer, the road load simulator (RLS), is being used at NASA's Lewis Research Center to test and evaluate electric vehicle propulsion systems developed under DOE's Electric and Hybrid Vehicle Program. To improve correlation between system tests on the RLS and track tests, similar tests were conducted on the same propulsion system on the RLS and on a test track. These tests are compared in this report. Battery current to maintain a constant vehicle speed with a fixed throttle was used for the comparison. Scatter in the data was greater in the track test results. This is attributable to variations in tire rolling resistance and wind effects in the track data. It also appeared that the RLS road load, determined by coastdown tests on the track, was lower than that of the vehicle on the track. These differences may be due to differences in tire temperature.
Assessment of primary health care: health professionals' perspective.
Silva, Simone Albino da; Nogueira, Denismar Alves; Paraizo, Camila Maria da Silva; Fracolli, Lislaine Aparecida
2014-08-01
Objective To assess primary health care attributes of access to a first contact, comprehensiveness, coordination, continuity, family guidance and community orientation. Method An evaluative, quantitative and cross-sectional study with 35 professional teams in the Family Health Program of the Alfenas region, Minas Gerais, Brazil. Data collection was done with the Primary Care Assessment Tool - Brazil, professional version. Results Results revealed a low percentage of medical experts among the participants who evaluated the attributes with high scores, with the exception of access to a first contact. Data analysis revealed needs for improvement: hours of service; forms of communication between clients and healthcare services and between clients and professionals; the mechanism of counter-referral. Conclusion It was concluded that there is a mismatch between the provision of services and the needs of the population, which compromises the quality of primary health care.
Two new methods to increase the contrast of track-etch neutron radiographs
NASA Technical Reports Server (NTRS)
Morley, J.
1973-01-01
In one method, fluorescent dye is deposited into tracks of radiograph and viewed under ultraviolet light. In second method, track-etch radiograph is placed between crossed polaroid filters, exposed to diffused light and resulting image is projected onto photographic film.
CellProfiler Tracer: exploring and validating high-throughput, time-lapse microscopy image data.
Bray, Mark-Anthony; Carpenter, Anne E
2015-11-04
Time-lapse analysis of cellular images is an important and growing need in biology. Algorithms for cell tracking are widely available; what researchers have been missing is a single open-source software package to visualize standard tracking output (from software like CellProfiler) in a way that allows convenient assessment of track quality, especially for researchers tuning tracking parameters for high-content time-lapse experiments. This makes quality assessment and algorithm adjustment a substantial challenge, particularly when dealing with hundreds of time-lapse movies collected in a high-throughput manner. We present CellProfiler Tracer, a free and open-source tool that complements the object tracking functionality of the CellProfiler biological image analysis package. Tracer allows multi-parametric morphological data to be visualized on object tracks, providing visualizations that have already been validated within the scientific community for time-lapse experiments, and combining them with simple graph-based measures for highlighting possible tracking artifacts. CellProfiler Tracer is a useful, free tool for inspection and quality control of object tracking data, available from http://www.cellprofiler.org/tracer/.
Detection and Tracking of Moving Objects with Real-Time Onboard Vision System
NASA Astrophysics Data System (ADS)
Erokhin, D. Y.; Feldman, A. B.; Korepanov, S. E.
2017-05-01
Detection of moving objects in video sequence received from moving video sensor is a one of the most important problem in computer vision. The main purpose of this work is developing set of algorithms, which can detect and track moving objects in real time computer vision system. This set includes three main parts: the algorithm for estimation and compensation of geometric transformations of images, an algorithm for detection of moving objects, an algorithm to tracking of the detected objects and prediction their position. The results can be claimed to create onboard vision systems of aircraft, including those relating to small and unmanned aircraft.
NASA Astrophysics Data System (ADS)
Chen, Zhu-an; Zhang, Li-ting; Liu, Lu
2009-10-01
ESRI's GIS components MapObjects are applied in many cadastral information system because of its miniaturization and flexibility. Some cadastral information was saved in cadastral database directly by MapObjects's Shape file format in this cadastral information system. However, MapObjects didn't provide the function of building attribute field for map layer's attribute data file in cadastral database and user cann't save the result of analysis. This present paper designed and realized the function of building attribute field in MapObjects based on the method of Jackson's system development.
Definition, Capabilities, and Components of a Terrestrial Carbon Monitoring System
NASA Technical Reports Server (NTRS)
West, Tristram O.; Brown, Molly E.; Duren, Riley M.; Ogle, Stephen M.; Moss, Richard H.
2013-01-01
Research efforts for effectively and consistently monitoring terrestrial carbon are increasing in number. As such, there is a need to define carbon monitoring and how it relates to carbon cycle science and carbon management. There is also a need to identify capabilities of a carbon monitoring system and the system components needed to develop the capabilities. Capabilities that enable the effective application of a carbon monitoring system for monitoring and management purposes may include: reconciling carbon stocks and fluxes, developing consistency across spatial and temporal scales, tracking horizontal movement of carbon, attribution of emissions to originating sources, cross-sectoral accounting, uncertainty quantification, redundancy and policy relevance. Focused research is needed to integrate these capabilities for sustained estimates of carbon stocks and fluxes. Additionally, if monitoring is intended to inform management decisions, management priorities should be considered prior to development of a monitoring system.
Encouraging data citation and discovery with the Data Citation Index.
Force, Megan M; Robinson, Nigel J
2014-10-01
An overview of the Data Citation Index is provided. Thomson Reuters developed this resource in response to a stated desire among members of the research community for increased attribution of non-traditional scholarly output. Launched in October of 2012 on the Web of science research platform, its aims include linking published research articles to their underlying data sets and tracking the citation of the data, as well as encouraging bibliographic citation of data. Cross-disciplinary search capabilities in the Index enable new possibilities for data discovery and synthesis. Data repositories are evaluated with respect to various selection criteria, with particular attention to their relevance to scientific and scholarly research. Index content reflects current data deposition practices. As data citation standards and practices continue to move toward widespread formalization and adoption, the initiative seeks to address issues of data citation, reuse, and author credit in a developing climate.
Encouraging data citation and discovery with the Data Citation Index
NASA Astrophysics Data System (ADS)
Force, Megan M.; Robinson, Nigel J.
2014-10-01
An overview of the Data Citation Index is provided. Thomson Reuters developed this resource in response to a stated desire among members of the research community for increased attribution of non-traditional scholarly output. Launched in October of 2012 on the Web of science research platform, its aims include linking published research articles to their underlying data sets and tracking the citation of the data, as well as encouraging bibliographic citation of data. Cross-disciplinary search capabilities in the Index enable new possibilities for data discovery and synthesis. Data repositories are evaluated with respect to various selection criteria, with particular attention to their relevance to scientific and scholarly research. Index content reflects current data deposition practices. As data citation standards and practices continue to move toward widespread formalization and adoption, the initiative seeks to address issues of data citation, reuse, and author credit in a developing climate.
ERIC Educational Resources Information Center
Keane, Brian P.; Mettler, Everett; Tsoi, Vicky; Kellman, Philip J.
2011-01-01
Multiple object tracking (MOT) is an attentional task wherein observers attempt to track multiple targets among moving distractors. Contour interpolation is a perceptual process that fills-in nonvisible edges on the basis of how surrounding edges (inducers) are spatiotemporally related. In five experiments, we explored the automaticity of…
Shiraishi, Satomi; Grams, Michael P; Fong de Los Santos, Luis E
2018-05-01
The purpose of this study was to demonstrate an objective quality control framework for the image review process. A total of 927 cone-beam computed tomography (CBCT) registrations were retrospectively analyzed for 33 bilateral head and neck cancer patients who received definitive radiotherapy. Two registration tracking volumes (RTVs) - cervical spine (C-spine) and mandible - were defined, within which a similarity metric was calculated and used as a registration quality tracking metric over the course of treatment. First, sensitivity to large misregistrations was analyzed for normalized cross-correlation (NCC) and mutual information (MI) in the context of statistical analysis. The distribution of metrics was obtained for displacements that varied according to a normal distribution with standard deviation of σ = 2 mm, and the detectability of displacements greater than 5 mm was investigated. Then, similarity metric control charts were created using a statistical process control (SPC) framework to objectively monitor the image registration and review process. Patient-specific control charts were created using NCC values from the first five fractions to set a patient-specific process capability limit. Population control charts were created using the average of the first five NCC values for all patients in the study. For each patient, the similarity metrics were calculated as a function of unidirectional translation, referred to as the effective displacement. Patient-specific action limits corresponding to 5 mm effective displacements were defined. Furthermore, effective displacements of the ten registrations with the lowest similarity metrics were compared with a three dimensional (3DoF) couch displacement required to align the anatomical landmarks. Normalized cross-correlation identified suboptimal registrations more effectively than MI within the framework of SPC. Deviations greater than 5 mm were detected at 2.8σ and 2.1σ from the mean for NCC and MI, respectively. Patient-specific control charts using NCC evaluated daily variation and identified statistically significant deviations. This study also showed that subjective evaluations of the images were not always consistent. Population control charts identified a patient whose tracking metrics were significantly lower than those of other patients. The patient-specific action limits identified registrations that warranted immediate evaluation by an expert. When effective displacements in the anterior-posterior direction were compared to 3DoF couch displacements, the agreement was ±1 mm for seven of 10 patients for both C-spine and mandible RTVs. Qualitative review alone of IGRT images can result in inconsistent feedback to the IGRT process. Registration tracking using NCC objectively identifies statistically significant deviations. When used in conjunction with the current image review process, this tool can assist in improving the safety and consistency of the IGRT process. © 2018 American Association of Physicists in Medicine.
Multi-ball and one-ball geolocation and location verification
NASA Astrophysics Data System (ADS)
Nelson, D. J.; Townsend, J. L.
2017-05-01
We present analysis methods that may be used to geolocate emitters using one or more moving receivers. While some of the methods we present may apply to a broader class of signals, our primary interest is locating and tracking ships from short pulsed transmissions, such as the maritime Automatic Identification System (AIS.) The AIS signal is difficult to process and track since the pulse duration is only 25 milliseconds, and the pulses may only be transmitted every six to ten seconds. Several fundamental problems are addressed, including demodulation of AIS/GMSK signals, verification of the emitter location, accurate frequency and delay estimation and identification of pulse trains from the same emitter. In particular, we present several new correlation methods, including cross-cross correlation that greatly improves correlation accuracy over conventional methods and cross- TDOA and cross-FDOA functions that make it possible to estimate time and frequency delay without the need of computing a two dimensional cross-ambiguity surface. By isolating pulses from the same emitter and accurately tracking the received signal frequency, we are able to accurately estimate the emitter location from the received Doppler characteristics.
NASA Astrophysics Data System (ADS)
Bouaynaya, N.; Schonfeld, Dan
2005-03-01
Many real world applications in computer and multimedia such as augmented reality and environmental imaging require an elastic accurate contour around a tracked object. In the first part of the paper we introduce a novel tracking algorithm that combines a motion estimation technique with the Bayesian Importance Sampling framework. We use Adaptive Block Matching (ABM) as the motion estimation technique. We construct the proposal density from the estimated motion vector. The resulting algorithm requires a small number of particles for efficient tracking. The tracking is adaptive to different categories of motion even with a poor a priori knowledge of the system dynamics. Particulary off-line learning is not needed. A parametric representation of the object is used for tracking purposes. In the second part of the paper, we refine the tracking output from a parametric sample to an elastic contour around the object. We use a 1D active contour model based on a dynamic programming scheme to refine the output of the tracker. To improve the convergence of the active contour, we perform the optimization over a set of randomly perturbed initial conditions. Our experiments are applied to head tracking. We report promising tracking results in complex environments.
Barrier Effects in Non-retinotopic Feature Attribution
Aydin, Murat; Herzog, Michael H.; Öğmen, Haluk
2011-01-01
When objects move in the environment, their retinal images can undergo drastic changes and features of different objects can be inter-mixed in the retinal image. Notwithstanding these changes and ambiguities, the visual system is capable of establishing correctly feature-object relationships as well as maintaining individual identities of objects through space and time. Recently, by using a Ternus-Pikler display, we have shown that perceived motion correspondences serve as the medium for non-retinotopic attribution of features to objects. The purpose of the work reported in this manuscript was to assess whether perceived motion correspondences provide a sufficient condition for feature attribution. Our results show that the introduction of a static “barrier” stimulus can interfere with the feature attribution process. Our results also indicate that the barrier stops feature attribution based on interferences related to the feature attribution process itself rather than on mechanisms related to perceived motion. PMID:21767561
Eccentricity and argument of perigee control for orbits with repeat ground tracks
NASA Technical Reports Server (NTRS)
Vincent, Mark A.
1992-01-01
In order to gain an understanding into the problem of eccentricity (e) and argument of perigee (omega) control for TOPEX/Poseidon, the two cases where the highest latitude crossing time and one of the equator crossings are held constant are investigated. Variations in e and omega cause a significant effect on the satellite's ground-track repeatability. Maintaining e and omega near their frozen values will minimize this variation. Analytical expressions are found to express this relationship while keeping an arbitrary point of the ground track fixed. The initial offset of the ground track from its nominal path determines the subsequent evolution of e and omega about their frozen values. This long-term behavior is numerically determined using an earth gravitational field including the first 17 zonal harmonics. The numerical results are plotted together with the analytical constraints to see if the later values of e and omega cause unacceptable deviation in the ground track.
Object tracking with adaptive HOG detector and adaptive Rao-Blackwellised particle filter
NASA Astrophysics Data System (ADS)
Rosa, Stefano; Paleari, Marco; Ariano, Paolo; Bona, Basilio
2012-01-01
Scenarios for a manned mission to the Moon or Mars call for astronaut teams to be accompanied by semiautonomous robots. A prerequisite for human-robot interaction is the capability of successfully tracking humans and objects in the environment. In this paper we present a system for real-time visual object tracking in 2D images for mobile robotic systems. The proposed algorithm is able to specialize to individual objects and to adapt to substantial changes in illumination and object appearance during tracking. The algorithm is composed by two main blocks: a detector based on Histogram of Oriented Gradient (HOG) descriptors and linear Support Vector Machines (SVM), and a tracker which is implemented by an adaptive Rao-Blackwellised particle filter (RBPF). The SVM is re-trained online on new samples taken from previous predicted positions. We use the effective sample size to decide when the classifier needs to be re-trained. Position hypotheses for the tracked object are the result of a clustering procedure applied on the set of particles. The algorithm has been tested on challenging video sequences presenting strong changes in object appearance, illumination, and occlusion. Experimental tests show that the presented method is able to achieve near real-time performances with a precision of about 7 pixels on standard video sequences of dimensions 320 × 240.
Deterministic object tracking using Gaussian ringlet and directional edge features
NASA Astrophysics Data System (ADS)
Krieger, Evan W.; Sidike, Paheding; Aspiras, Theus; Asari, Vijayan K.
2017-10-01
Challenges currently existing for intensity-based histogram feature tracking methods in wide area motion imagery (WAMI) data include object structural information distortions, background variations, and object scale change. These issues are caused by different pavement or ground types and from changing the sensor or altitude. All of these challenges need to be overcome in order to have a robust object tracker, while attaining a computation time appropriate for real-time processing. To achieve this, we present a novel method, Directional Ringlet Intensity Feature Transform (DRIFT), which employs Kirsch kernel filtering for edge features and a ringlet feature mapping for rotational invariance. The method also includes an automatic scale change component to obtain accurate object boundaries and improvements for lowering computation times. We evaluated the DRIFT algorithm on two challenging WAMI datasets, namely Columbus Large Image Format (CLIF) and Large Area Image Recorder (LAIR), to evaluate its robustness and efficiency. Additional evaluations on general tracking video sequences are performed using the Visual Tracker Benchmark and Visual Object Tracking 2014 databases to demonstrate the algorithms ability with additional challenges in long complex sequences including scale change. Experimental results show that the proposed approach yields competitive results compared to state-of-the-art object tracking methods on the testing datasets.
Precise orbit computation and sea surface modeling
NASA Technical Reports Server (NTRS)
Wakker, Karel F.; Ambrosius, B. A. C.; Rummel, R.; Vermaat, E.; Deruijter, W. P. M.; Vandermade, J. W.; Zimmerman, J. T. F.
1991-01-01
The research project described below is part of a long-term program at Delft University of Technology aiming at the application of European Remote Sensing satellite (ERS-1) and TOPEX/POSEIDON altimeter measurements for geophysical purposes. This program started in 1980 with the processing of Seasat laser range and altimeter height measurements and concentrates today on the analysis of Geosat altimeter data. The objectives of the TOPEX/POSEIDON research project are the tracking of the satellite by the Dutch mobile laser tracking system MTLRS-2, the computation of precise TOPEX/POSEIDON orbits, the analysis of the spatial and temporal distribution of the orbit errors, the improvement of ERS-1 orbits through the information obtained from the altimeter crossover difference residuals for crossing ERS-1 and TOPEX/POSEIDON tracks, the combination of ERS-1 and TOPEX/POSEIDON altimeter data into a single high-precision data set, and the application of this data set to model the sea surface. The latter application will focus on the determination of detailed regional mean sea surfaces, sea surface variability, ocean topography, and ocean currents in the North Atlantic, the North Sea, the seas around Indonesia, the West Pacific, and the oceans around South Africa.
Real-time tracking of visually attended objects in virtual environments and its application to LOD.
Lee, Sungkil; Kim, Gerard Jounghyun; Choi, Seungmoon
2009-01-01
This paper presents a real-time framework for computationally tracking objects visually attended by the user while navigating in interactive virtual environments. In addition to the conventional bottom-up (stimulus-driven) saliency map, the proposed framework uses top-down (goal-directed) contexts inferred from the user's spatial and temporal behaviors, and identifies the most plausibly attended objects among candidates in the object saliency map. The computational framework was implemented using GPU, exhibiting high computational performance adequate for interactive virtual environments. A user experiment was also conducted to evaluate the prediction accuracy of the tracking framework by comparing objects regarded as visually attended by the framework to actual human gaze collected with an eye tracker. The results indicated that the accuracy was in the level well supported by the theory of human cognition for visually identifying single and multiple attentive targets, especially owing to the addition of top-down contextual information. Finally, we demonstrate how the visual attention tracking framework can be applied to managing the level of details in virtual environments, without any hardware for head or eye tracking.
Robust multiperson tracking from a mobile platform.
Ess, Andreas; Leibe, Bastian; Schindler, Konrad; van Gool, Luc
2009-10-01
In this paper, we address the problem of multiperson tracking in busy pedestrian zones using a stereo rig mounted on a mobile platform. The complexity of the problem calls for an integrated solution that extracts as much visual information as possible and combines it through cognitive feedback cycles. We propose such an approach, which jointly estimates camera position, stereo depth, object detection, and tracking. The interplay between those components is represented by a graphical model. Since the model has to incorporate object-object interactions and temporal links to past frames, direct inference is intractable. We, therefore, propose a two-stage procedure: for each frame, we first solve a simplified version of the model (disregarding interactions and temporal continuity) to estimate the scene geometry and an overcomplete set of object detections. Conditioned on these results, we then address object interactions, tracking, and prediction in a second step. The approach is experimentally evaluated on several long and difficult video sequences from busy inner-city locations. Our results show that the proposed integration makes it possible to deliver robust tracking performance in scenes of realistic complexity.
Accurate object tracking system by integrating texture and depth cues
NASA Astrophysics Data System (ADS)
Chen, Ju-Chin; Lin, Yu-Hang
2016-03-01
A robust object tracking system that is invariant to object appearance variations and background clutter is proposed. Multiple instance learning with a boosting algorithm is applied to select discriminant texture information between the object and background data. Additionally, depth information, which is important to distinguish the object from a complicated background, is integrated. We propose two depth-based models that can compensate texture information to cope with both appearance variants and background clutter. Moreover, in order to reduce the risk of drifting problem increased for the textureless depth templates, an update mechanism is proposed to select more precise tracking results to avoid incorrect model updates. In the experiments, the robustness of the proposed system is evaluated and quantitative results are provided for performance analysis. Experimental results show that the proposed system can provide the best success rate and has more accurate tracking results than other well-known algorithms.
Infrared tag and track technique
Partin, Judy K.; Stone, Mark L.; Slater, John; Davidson, James R.
2007-12-04
A method of covertly tagging an object for later tracking includes providing a material capable of at least one of being applied to the object and being included in the object, which material includes deuterium; and performing at least one of applying the material to the object and including the material in the object in a manner in which in the appearance of the object is not changed, to the naked eye.
NASA Technical Reports Server (NTRS)
1983-01-01
The overall configuration and modules of the initial and evolved space station are described as well as tended industrial and polar platforms. The mass properties that are the basis for costing are summarized. User friendly attributes (interfaces, resources, and facilities) are identified for commercial; science and applications; industrial park; international participation; national security; and the external tank option. Configuration alternates studied to determine a baseline are examined. Commonality for clustered 3-man and 9-man stations are considered as well as the use of tethered platforms. Requirements are indicated for electrical, communication and tracking; data management Subsystem requirements for electrical, data management, communication and tracking, environment control/life support system; and guidance navigation and control subsystems are identified.
NASA Astrophysics Data System (ADS)
1983-04-01
The overall configuration and modules of the initial and evolved space station are described as well as tended industrial and polar platforms. The mass properties that are the basis for costing are summarized. User friendly attributes (interfaces, resources, and facilities) are identified for commercial; science and applications; industrial park; international participation; national security; and the external tank option. Configuration alternates studied to determine a baseline are examined. Commonality for clustered 3-man and 9-man stations are considered as well as the use of tethered platforms. Requirements are indicated for electrical, communication and tracking; data management Subsystem requirements for electrical, data management, communication and tracking, environment control/life support system; and guidance navigation and control subsystems are identified.
McCrea, Richard T.; Buckley, Lisa G.; Farlow, James O.; Lockley, Martin G.; Currie, Philip J.; Matthews, Neffra A.; Pemberton, S. George
2014-01-01
The skeletal record of tyrannosaurids is well-documented, whereas their footprint record is surprisingly sparse. There are only a few isolated footprints attributed to tyrannosaurids and, hitherto, no reported trackways. We report the world’s first trackways attributable to tyrannosaurids, and describe a new ichnotaxon attributable to tyrannosaurids. These trackways are from the Upper Cretaceous (Campanian - Maastrichtian) of northeastern British Columbia, Canada. One trackway consists of three tridactyl footprints, and two adjacent trackways consist of two footprints each. All three trackways show animals bearing southeast within an 8.5 meter-wide corridor. Similarities in depth and preservation of the tyrannosaurid tracks indicate that these three trackways were made by track-makers walking concurrently in the same direction. These trackways add significantly to previous osteology-based hypotheses of locomotion and behavior in Tyrannosauridae by providing ichnologic support for gregariousness in tyrannosaurids, and the first record of the walking gait of tyrannosaurids. PMID:25054328
Verschuur, Carl
2009-03-01
Difficulties in speech recognition experienced by cochlear implant users may be attributed both to information loss caused by signal processing and to information loss associated with the interface between the electrode array and auditory nervous system, including cross-channel interaction. The objective of the work reported here was to attempt to partial out the relative contribution of these different factors to consonant recognition. This was achieved by comparing patterns of consonant feature recognition as a function of channel number and presence/absence of background noise in users of the Nucleus 24 device with normal hearing subjects listening to acoustic models that mimicked processing of that device. Additionally, in the acoustic model experiment, a simulation of cross-channel spread of excitation, or "channel interaction," was varied. Results showed that acoustic model experiments were highly correlated with patterns of performance in better-performing cochlear implant users. Deficits to consonant recognition in this subgroup could be attributed to cochlear implant processing, whereas channel interaction played a much smaller role in determining performance errors. The study also showed that large changes to channel number in the Advanced Combination Encoder signal processing strategy led to no substantial changes in performance.
Tracking target objects orbiting earth using satellite-based telescopes
De Vries, Willem H; Olivier, Scot S; Pertica, Alexander J
2014-10-14
A system for tracking objects that are in earth orbit via a constellation or network of satellites having imaging devices is provided. An object tracking system includes a ground controller and, for each satellite in the constellation, an onboard controller. The ground controller receives ephemeris information for a target object and directs that ephemeris information be transmitted to the satellites. Each onboard controller receives ephemeris information for a target object, collects images of the target object based on the expected location of the target object at an expected time, identifies actual locations of the target object from the collected images, and identifies a next expected location at a next expected time based on the identified actual locations of the target object. The onboard controller processes the collected image to identify the actual location of the target object and transmits the actual location information to the ground controller.
NASA Astrophysics Data System (ADS)
Cai, Lei; Wang, Lin; Li, Bo; Zhang, Libao; Lv, Wen
2017-06-01
Vehicle tracking technology is currently one of the most active research topics in machine vision. It is an important part of intelligent transportation system. However, in theory and technology, it still faces many challenges including real-time and robustness. In video surveillance, the targets need to be detected in real-time and to be calculated accurate position for judging the motives. The contents of video sequence images and the target motion are complex, so the objects can't be expressed by a unified mathematical model. Object-tracking is defined as locating the interest moving target in each frame of a piece of video. The current tracking technology can achieve reliable results in simple environment over the target with easy identified characteristics. However, in more complex environment, it is easy to lose the target because of the mismatch between the target appearance and its dynamic model. Moreover, the target usually has a complex shape, but the tradition target tracking algorithm usually represents the tracking results by simple geometric such as rectangle or circle, so it cannot provide accurate information for the subsequent upper application. This paper combines a traditional object-tracking technology, Mean-Shift algorithm, with a kind of image segmentation algorithm, Active-Contour model, to get the outlines of objects while the tracking process and automatically handle topology changes. Meanwhile, the outline information is used to aid tracking algorithm to improve it.
Moving object detection and tracking in videos through turbulent medium
NASA Astrophysics Data System (ADS)
Halder, Kalyan Kumar; Tahtali, Murat; Anavatti, Sreenatha G.
2016-06-01
This paper addresses the problem of identifying and tracking moving objects in a video sequence having a time-varying background. This is a fundamental task in many computer vision applications, though a very challenging one because of turbulence that causes blurring and spatiotemporal movements of the background images. Our proposed approach involves two major steps. First, a moving object detection algorithm that deals with the detection of real motions by separating the turbulence-induced motions using a two-level thresholding technique is used. In the second step, a feature-based generalized regression neural network is applied to track the detected objects throughout the frames in the video sequence. The proposed approach uses the centroid and area features of the moving objects and creates the reference regions instantly by selecting the objects within a circle. Simulation experiments are carried out on several turbulence-degraded video sequences and comparisons with an earlier method confirms that the proposed approach provides a more effective tracking of the targets.
Zhong, Sheng-hua; Ma, Zheng; Wilson, Colin; Liu, Yan; Flombaum, Jonathan I
2014-01-01
Intuitively, extrapolating object trajectories should make visual tracking more accurate. This has proven to be true in many contexts that involve tracking a single item. But surprisingly, when tracking multiple identical items in what is known as “multiple object tracking,” observers often appear to ignore direction of motion, relying instead on basic spatial memory. We investigated potential reasons for this behavior through probabilistic models that were endowed with perceptual limitations in the range of typical human observers, including noisy spatial perception. When we compared a model that weights its extrapolations relative to other sources of information about object position, and one that does not extrapolate at all, we found no reliable difference in performance, belying the intuition that extrapolation always benefits tracking. In follow-up experiments we found this to be true for a variety of models that weight observations and predictions in different ways; in some cases we even observed worse performance for models that use extrapolations compared to a model that does not at all. Ultimately, the best performing models either did not extrapolate, or extrapolated very conservatively, relying heavily on observations. These results illustrate the difficulty and attendant hazards of using noisy inputs to extrapolate the trajectories of multiple objects simultaneously in situations with targets and featurally confusable nontargets. PMID:25311300
Connection-based and object-based grouping in multiple-object tracking: A developmental study.
Van der Hallen, Ruth; Reusens, Julie; Evers, Kris; de-Wit, Lee; Wagemans, Johan
2018-03-30
Developmental research on Gestalt laws has previously revealed that, even as young as infancy, we are bound to group visual elements into unitary structures in accordance with a variety of organizational principles. Here, we focus on the developmental trajectory of both connection-based and object-based grouping, and investigate their impact on object formation in participants, aged 9-21 years old (N = 113), using a multiple-object tracking paradigm. Results reveal a main effect of both age and grouping type, indicating that 9- to 21-year-olds are sensitive to both connection-based and object-based grouping interference, and tracking ability increases with age. In addition to its importance for typical development, these results provide an informative baseline to understand clinical aberrations in this regard. Statement of contribution What is already known on this subject? The origin of the Gestalt principles is still an ongoing debate: Are they innate, learned over time, or both? Developmental research has revealed how each Gestalt principle has its own trajectory and unique relationship to visual experience. Both connectedness and object-based grouping play an important role in object formation during childhood. What does this study add? The study identifies how sensitivity to connectedness and object-based grouping evolves in individuals, aged 9-21 years old. Using multiple-object tracking, results reveal that the ability to track multiple objects increases with age. These results provide an informative baseline to understand clinical aberrations in different types of grouping. © 2018 The Authors. British Journal of Developmental Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.
Effects of roadside habitat and fox density on a snow track survey for foxes in Ohio
Stanley, Thomas R.; Bart, Jonathan
1991-01-01
Many methods have been used to survey red fox (Vulpes vulpes) and gray fox (Urocyon dnereoargenteus) populations. However, none has proven entirely satisfactory, and wild foxes remain one of the most difficult economically important wildlife species to monitor. In this study we evaluated the reliability of a snow track survey method for foxes by investigating whether the average number of road crossings per fox is influenced by changes in roadside habitat or changes in fox density. Several snow track surveys were conducted in two Ohio counties during January and February, 1984. Data on roadside habitat, relative fox densities, and fox crossings were collected. Results suggested that changes in roadside habitat could influence the average number of crossings per fox and, therefore, changes in the index could occur independent of actual population changes. We found no evidence that crossings per fox varied with fox density, but further research is needed to substantiate this finding.
Memory Performance for Everyday Motivational and Neutral Objects Is Dissociable from Attention
Schomaker, Judith; Wittmann, Bianca C.
2017-01-01
Episodic memory is typically better for items coupled with monetary reward or punishment during encoding. It is yet unclear whether memory is also enhanced for everyday objects with appetitive or aversive values learned through a lifetime of experience, and to what extent episodic memory enhancement for motivational and neutral items is attributable to attention. In a first experiment, we investigated attention to everyday motivational objects using eye-tracking during free-viewing and subsequently tested episodic memory using a remember/know procedure. Attention was directed more to aversive stimuli, as evidenced by longer viewing durations, whereas recollection was higher for both appetitive and aversive objects. In the second experiment, we manipulated the visual contrast of neutral objects through changes of contrast to further dissociate attention and memory encoding. While objects presented with high visual contrast were looked at longer, recollection was best for objects presented in unmodified, medium contrast. Generalized logistic mixed models on recollection performance showed that attention as measured by eye movements did not enhance subsequent memory, while motivational value (Experiment 1) and visual contrast (Experiment 2) had quadratic effects in opposite directions. Our findings suggest that an enhancement of incidental memory encoding for appetitive items can occur without an increase in attention and, vice versa, that enhanced attention towards salient neutral objects is not necessarily associated with memory improvement. Together, our results provide evidence for a double dissociation of attention and memory effects under certain conditions. PMID:28694774
Xiao, Jingjing; Stolkin, Rustam; Gao, Yuqing; Leonardis, Ales
2017-09-06
This paper presents a novel robust method for single target tracking in RGB-D images, and also contributes a substantial new benchmark dataset for evaluating RGB-D trackers. While a target object's color distribution is reasonably motion-invariant, this is not true for the target's depth distribution, which continually varies as the target moves relative to the camera. It is therefore nontrivial to design target models which can fully exploit (potentially very rich) depth information for target tracking. For this reason, much of the previous RGB-D literature relies on color information for tracking, while exploiting depth information only for occlusion reasoning. In contrast, we propose an adaptive range-invariant target depth model, and show how both depth and color information can be fully and adaptively fused during the search for the target in each new RGB-D image. We introduce a new, hierarchical, two-layered target model (comprising local and global models) which uses spatio-temporal consistency constraints to achieve stable and robust on-the-fly target relearning. In the global layer, multiple features, derived from both color and depth data, are adaptively fused to find a candidate target region. In ambiguous frames, where one or more features disagree, this global candidate region is further decomposed into smaller local candidate regions for matching to local-layer models of small target parts. We also note that conventional use of depth data, for occlusion reasoning, can easily trigger false occlusion detections when the target moves rapidly toward the camera. To overcome this problem, we show how combining target information with contextual information enables the target's depth constraint to be relaxed. Our adaptively relaxed depth constraints can robustly accommodate large and rapid target motion in the depth direction, while still enabling the use of depth data for highly accurate reasoning about occlusions. For evaluation, we introduce a new RGB-D benchmark dataset with per-frame annotated attributes and extensive bias analysis. Our tracker is evaluated using two different state-of-the-art methodologies, VOT and object tracking benchmark, and in both cases it significantly outperforms four other state-of-the-art RGB-D trackers from the literature.
NASA Astrophysics Data System (ADS)
Smeltzer, C. D.; Wang, Y.; Boersma, F.; Celarier, E. A.; Bucsela, E. J.
2013-12-01
We investigate the effects of retrieval radiation schemes and parameters on trend analysis using tropospheric nitrogen dioxide (NO2) vertical column density (VCD) measurements over the United States. Ozone Monitoring Instrument (OMI) observations from 2005 through 2012 are used in this analysis. We investigated two radiation schemes, provided by National Aeronautics and Space Administration (NASA TOMRAD) and Koninklijk Nederlands Meteorologisch Instituut (KNMI DAK). In addition, we analyzed trend dependence on radiation parameters, including surface albedo and viewing geometry. The cross-track mean VCD average difference is 10-15% between the two radiation schemes in 2005. As the OMI anomaly developed and progressively worsens, the difference between the two schemes becomes larger. Furthermore, applying surface albedo measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) leads to increases of estimated NO2 VCD trends over high-emission regions. We find that the uncertainties of OMI-derived NO2 VCD trends can be reduced by up to a factor of 3 by selecting OMI cross-track rows on the basis of their performance over the ocean [see abstract figure]. Comparison of OMI tropospheric VCD trends to those estimated based on the EPA surface NO2 observations indicate using MODIS surface albedo data and a more narrow selection of OMI cross-track rows greatly improves the agreement of estimated trends between satellite and surface data. This figure shows the reduction of uncertainty in OMI NO2 trend by selecting OMI cross-track rows based on the performance over the ocean. With this technique, uncertainties within the seasonal trend may be reduced by a factor of 3 or more (blue) compared with only removing the anomalous rows: considering OMI cross-track rows 4-24 (red).
Feature Integration in the Mapping of Multi-Attribute Visual Stimuli to Responses
Ishizaki, Takuya; Morita, Hiromi; Morita, Masahiko
2015-01-01
In the human visual system, different attributes of an object, such as shape and color, are separately processed in different modules and then integrated to elicit a specific response. In this process, different attributes are thought to be temporarily “bound” together by focusing attention on the object; however, how such binding contributes to stimulus-response mapping remains unclear. Here we report that learning and performance of stimulus-response tasks was more difficult when three attributes of the stimulus determined the correct response than when two attributes did. We also found that spatially separated presentations of attributes considerably complicated the task, although they did not markedly affect target detection. These results are consistent with a paired-attribute model in which bound feature pairs, rather than object representations, are associated with responses by learning. This suggests that attention does not bind three or more attributes into a unitary object representation, and long-term learning is required for their integration. PMID:25762010
Eye Movements during Multiple Object Tracking: Where Do Participants Look?
ERIC Educational Resources Information Center
Fehd, Hilda M.; Seiffert, Adriane E.
2008-01-01
Similar to the eye movements you might make when viewing a sports game, this experiment investigated where participants tend to look while keeping track of multiple objects. While eye movements were recorded, participants tracked either 1 or 3 of 8 red dots that moved randomly within a square box on a black background. Results indicated that…
Another Way of Tracking Moving Objects Using Short Video Clips
ERIC Educational Resources Information Center
Vera, Francisco; Romanque, Cristian
2009-01-01
Physics teachers have long employed video clips to study moving objects in their classrooms and instructional labs. A number of approaches exist, both free and commercial, for tracking the coordinates of a point using video. The main characteristics of the method described in this paper are: it is simple to use; coordinates can be tracked using…
Comparative analysis of three different methods for monitoring the use of green bridges by wildlife.
Gužvica, Goran; Bošnjak, Ivana; Bielen, Ana; Babić, Danijel; Radanović-Gužvica, Biserka; Šver, Lidija
2014-01-01
Green bridges are used to decrease highly negative impact of roads/highways on wildlife populations and their effectiveness is evaluated by various monitoring methods. Based on the 3-year monitoring of four Croatian green bridges, we compared the effectiveness of three indirect monitoring methods: track-pads, camera traps and active infrared (IR) trail monitoring system. The ability of the methods to detect different species and to give good estimation of number of animal crossings was analyzed. The accuracy of species detection by track-pad method was influenced by granulometric composition of track-pad material, with the best results obtained with higher percentage of silt and clay. We compared the species composition determined by track-pad and camera trap methods and found that monitoring by tracks underestimated the ratio of small canids, while camera traps underestimated the ratio of roe deer. Regarding total number of recorder events, active IR detectors recorded from 11 to 19 times more events then camera traps and app. 80% of them were not caused by animal crossings. Camera trap method underestimated the real number of total events. Therefore, an algorithm for filtration of the IR dataset was developed for approximation of the real number of crossings. Presented results are valuable for future monitoring of wildlife crossings in Croatia and elsewhere, since advantages and disadvantages of used monitoring methods are shown. In conclusion, different methods should be chosen/combined depending on the aims of the particular monitoring study.
Single and Multiple Object Tracking Using a Multi-Feature Joint Sparse Representation.
Hu, Weiming; Li, Wei; Zhang, Xiaoqin; Maybank, Stephen
2015-04-01
In this paper, we propose a tracking algorithm based on a multi-feature joint sparse representation. The templates for the sparse representation can include pixel values, textures, and edges. In the multi-feature joint optimization, noise or occlusion is dealt with using a set of trivial templates. A sparse weight constraint is introduced to dynamically select the relevant templates from the full set of templates. A variance ratio measure is adopted to adaptively adjust the weights of different features. The multi-feature template set is updated adaptively. We further propose an algorithm for tracking multi-objects with occlusion handling based on the multi-feature joint sparse reconstruction. The observation model based on sparse reconstruction automatically focuses on the visible parts of an occluded object by using the information in the trivial templates. The multi-object tracking is simplified into a joint Bayesian inference. The experimental results show the superiority of our algorithm over several state-of-the-art tracking algorithms.
Quantitative observations on tropical cyclone tracks in the Arabian Sea
NASA Astrophysics Data System (ADS)
Terry, James P.; Gienko, Gennady
2018-03-01
The Arabian Sea basin represents a minor component of global total cyclones annually and has not featured so prominently in cyclone research compared with other basins where greater numbers of cyclones are registered each year. This paper presents the results of exploratory analysis of various features of cyclone tracks in the Arabian Sea, with a particular focus on examining their temporal and spatial patterns. Track morphometry also reveals further information on track shape. The study indicates how cyclones spawned during May in the early pre-monsoon period (often strong events) have a tendency to follow more sinuous tracks, whereas cyclones occurring in October in the post-monsoon period tend to follow straighter tracks. Track sinuosity is significantly related to other attributes, including cyclone longevity and intensity. Comparisons are also drawn between the general characteristics of cyclone tracks in the Arabian Sea and other ocean basins, suggesting how the size and geography of the Arabian Sea basin exert influences on these characteristics.
MetaTracker: integration and abstraction of 3D motion tracking data from multiple hardware systems
NASA Astrophysics Data System (ADS)
Kopecky, Ken; Winer, Eliot
2014-06-01
Motion tracking has long been one of the primary challenges in mixed reality (MR), augmented reality (AR), and virtual reality (VR). Military and defense training can provide particularly difficult challenges for motion tracking, such as in the case of Military Operations in Urban Terrain (MOUT) and other dismounted, close quarters simulations. These simulations can take place across multiple rooms, with many fast-moving objects that need to be tracked with a high degree of accuracy and low latency. Many tracking technologies exist, such as optical, inertial, ultrasonic, and magnetic. Some tracking systems even combine these technologies to complement each other. However, there are no systems that provide a high-resolution, flexible, wide-area solution that is resistant to occlusion. While frameworks exist that simplify the use of tracking systems and other input devices, none allow data from multiple tracking systems to be combined, as if from a single system. In this paper, we introduce a method for compensating for the weaknesses of individual tracking systems by combining data from multiple sources and presenting it as a single tracking system. Individual tracked objects are identified by name, and their data is provided to simulation applications through a server program. This allows tracked objects to transition seamlessly from the area of one tracking system to another. Furthermore, it abstracts away the individual drivers, APIs, and data formats for each system, providing a simplified API that can be used to receive data from any of the available tracking systems. Finally, when single-piece tracking systems are used, those systems can themselves be tracked, allowing for real-time adjustment of the trackable area. This allows simulation operators to leverage limited resources in more effective ways, improving the quality of training.
Tracking with occlusions via graph cuts.
Papadakis, Nicolas; Bugeau, Aurélie
2011-01-01
This work presents a new method for tracking and segmenting along time-interacting objects within an image sequence. One major contribution of the paper is the formalization of the notion of visible and occluded parts. For each object, we aim at tracking these two parts. Assuming that the velocity of each object is driven by a dynamical law, predictions can be used to guide the successive estimations. Separating these predicted areas into good and bad parts with respect to the final segmentation and representing the objects with their visible and occluded parts permit handling partial and complete occlusions. To achieve this tracking, a label is assigned to each object and an energy function representing the multilabel problem is minimized via a graph cuts optimization. This energy contains terms based on image intensities which enable segmenting and regularizing the visible parts of the objects. It also includes terms dedicated to the management of the occluded and disappearing areas, which are defined on the areas of prediction of the objects. The results on several challenging sequences prove the strength of the proposed approach.
49 CFR 213.347 - Automotive or railroad crossings at grade.
Code of Federal Regulations, 2010 CFR
2010-10-01
... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION TRACK SAFETY STANDARDS Train Operations at Track Classes 6 and.../barrier system to address the protection of highway traffic and high speed trains. Trains shall not...-approved warning/barrier system exists on that track segment; and (2) All elements of that warning/barrier...
Robust Feedback Zoom Tracking for Digital Video Surveillance
Zou, Tengyue; Tang, Xiaoqi; Song, Bao; Wang, Jin; Chen, Jihong
2012-01-01
Zoom tracking is an important function in video surveillance, particularly in traffic management and security monitoring. It involves keeping an object of interest in focus during the zoom operation. Zoom tracking is typically achieved by moving the zoom and focus motors in lenses following the so-called “trace curve”, which shows the in-focus motor positions versus the zoom motor positions for a specific object distance. The main task of a zoom tracking approach is to accurately estimate the trace curve for the specified object. Because a proportional integral derivative (PID) controller has historically been considered to be the best controller in the absence of knowledge of the underlying process and its high-quality performance in motor control, in this paper, we propose a novel feedback zoom tracking (FZT) approach based on the geometric trace curve estimation and PID feedback controller. The performance of this approach is compared with existing zoom tracking methods in digital video surveillance. The real-time implementation results obtained on an actual digital video platform indicate that the developed FZT approach not only solves the traditional one-to-many mapping problem without pre-training but also improves the robustness for tracking moving or switching objects which is the key challenge in video surveillance. PMID:22969388
NASA Astrophysics Data System (ADS)
Laurenzis, Martin; Bacher, Emmanuel; Christnacher, Frank
2017-05-01
An increasing number of incidents are reported where small unmanned aerial vehicles (UAV) are involved flying at low altitude. Thus UAVs are becoming more and more a serious threat in civilian and military scenarios leading to serious danger to safety or privacy issues. In this context, the detection and tracking of small UAV flying at low altitude in urban environment or near background structures is a challenge for state of the art detection technologies. In this paper, we focus on detection, tracking and identification by laser sensing technologies that are Laser Gated Viewing and scanning LiDAR. The laser reflection cross-sections (LRCS) has direct impact on the probability to detection and capability for range measurement. Here, we present methods to determine the laser reflection cross-sections by experimental and computational approaches.
Dietary self-control is related to the speed with which health and taste attributes are processed
Sullivan, Nicolette; Hutcherson, Cendri; Harris, Alison; Rangel, Antonio
2015-01-01
We propose that self-control failures, and variation across individuals in self-control abilities, are partly due to differences in the speed with which the decision-making circuitry processes basic attributes like taste, versus more abstract attributes such as health. We test these hypotheses by combining a dietary choice task with a novel form of mouse tracking that allows us to pinpoint when different attributes are being integrated into the choice process with millisecond temporal resolution. We find that, on average, taste attributes are processed about 195 ms earlier than health attributes during the choice process. We also find that 13 - 39% of observed individual differences in self-control ability can be explained by differences in the relative speed with which taste and health attributes are processed. PMID:25515527
Zamecnik, Patrik; Schouten, Martijn G; Krafft, Axel J; Maier, Florian; Schlemmer, Heinz-Peter; Barentsz, Jelle O; Bock, Michael; Fütterer, Jurgen J
2014-12-01
To assess the feasibility of automatic needle-guide tracking by using a real-time phase-only cross correlation ( POCC phase-only cross correlation ) algorithm-based sequence for transrectal 3-T in-bore magnetic resonance (MR)-guided prostate biopsies. This study was approved by the ethics review board, and written informed consent was obtained from all patients. Eleven patients with a prostate-specific antigen level of at least 4 ng/mL (4 μg/L) and at least one transrectal ultrasonography-guided biopsy session with negative findings were enrolled. Regions suspicious for cancer were identified on 3-T multiparametric MR images. During a subsequent MR-guided biopsy, the regions suspicious for cancer were reidentified and targeted by using the POCC phase-only cross correlation -based tracking sequence. Besides testing a general technical feasibility of the biopsy procedure by using the POCC phase-only cross correlation -based tracking sequence, the procedure times were measured, and a pathologic analysis of the biopsy cores was performed. Thirty-eight core samples were obtained from 25 regions suspicious for cancer. It was technically feasible to perform the POCC phase-only cross correlation -based biopsies in all regions suspicious for cancer in each patient, with adequate biopsy samples obtained with each biopsy attempt. The median size of the region suspicious for cancer was 8 mm (range, 4-13 mm). In each region suspicious for cancer (median number per patient, two; range, 1-4), a median of one core sample per region was obtained (range, 1-3). The median time for guidance per target was 1.5 minutes (range, 0.7-5 minutes). Nineteen of 38 core biopsy samples contained cancer. This study shows that it is feasible to perform transrectal 3-T MR-guided biopsies by using a POCC phase-only cross correlation algorithm-based real-time tracking sequence. © RSNA, 2014.
Attribution Traits Versus Situations: The Cross-Situational Consistency of Attributions.
ERIC Educational Resources Information Center
Barke, Charles R.
While attributions have traditionally been viewed as social cognition variables, some researchers have proposed that individual differences exist in attributional patterns and that these patterns are differentially related to and predictive of various behaviors. A study was conducted to examine the question of attribution style as a trait-like…
Fast Track Extubation In Adult Patients On Pump Open Heart Surgery At A Tertiary Care Hospital.
Akhtar, Mohammad Irfan; Sharif, Hasanat; Hamid, Mohammad; Samad, Khalid; Khan, Fazal Hameed
2016-01-01
Fast-track cardiac surgery programs have been established as the standard of cardiac surgical care. Studies have shown that early extubation in elective cardiac surgery patients, including coronary and non-coronary open-heart surgery patients does not increase perioperative morbidity and mortality. The objective of this observational study was to determine the success and failure profile of fast track extubation (FTE) practice in adult open-heart surgical patients. The study was conducted at cardiac operating room and Cardiac Intensive Care Unit (CICU) of a tertiary care hospital for a period of nine months, i.e., from Oct 2014 to June-2015. All on pump elective adult cardiac surgery patients including isolated CABG, isolated Valve replacements, combined procedures and aortic root replacements were enrolled in the study. Standardized anesthetic technique was adopted. Surgical and bypass techniques were tailored according to the procedure. Success of Fast track extubation was defined as extubation within 6 hours of arrival in CICU. A total of 290 patients were recruited. The average age of the patients was 56.3±10.5 years. There were 77.6% male and 22.4% female patients. Overall success rate was 51.9% and failure rate was 48.1%. The peri-operative renal insufficiency, cross clamp time and CICU stay (hours) were significantly lower in success group. Re-intubation rate was 0.74%. The perioperative parameters were significantly better in success group and the safety was also demonstrated in the patients who were fast tracked successfully. To implement the practice in its full capacity and benefit, a fast track protocol needs to be devised to standardize the current practices and to disseminate the strategy among junior anaesthesiologists, perfusionists and nursing staff.
Normal aging delays and compromises early multifocal visual attention during object tracking.
Störmer, Viola S; Li, Shu-Chen; Heekeren, Hauke R; Lindenberger, Ulman
2013-02-01
Declines in selective attention are one of the sources contributing to age-related impairments in a broad range of cognitive functions. Most previous research on mechanisms underlying older adults' selection deficits has studied the deployment of visual attention to static objects and features. Here we investigate neural correlates of age-related differences in spatial attention to multiple objects as they move. We used a multiple object tracking task, in which younger and older adults were asked to keep track of moving target objects that moved randomly in the visual field among irrelevant distractor objects. By recording the brain's electrophysiological responses during the tracking period, we were able to delineate neural processing for targets and distractors at early stages of visual processing (~100-300 msec). Older adults showed less selective attentional modulation in the early phase of the visual P1 component (100-125 msec) than younger adults, indicating that early selection is compromised in old age. However, with a 25-msec delay relative to younger adults, older adults showed distinct processing of targets (125-150 msec), that is, a delayed yet intact attentional modulation. The magnitude of this delayed attentional modulation was related to tracking performance in older adults. The amplitude of the N1 component (175-210 msec) was smaller in older adults than in younger adults, and the target amplification effect of this component was also smaller in older relative to younger adults. Overall, these results indicate that normal aging affects the efficiency and timing of early visual processing during multiple object tracking.
Brusa, Jamie L
2017-12-30
Successful recruiting for collegiate track & field athletes has become a more competitive and essential component of coaching. This study aims to determine the relationship between race performances of distance runners at the United States high school and National Collegiate Athletic Association (NCAA) levels. Conditional inference classification tree models were built and analysed to predict the probability that runners would qualify for the NCAA Division I National Cross Country Meet and/or the East or West NCAA Division I Outdoor Track & Field Preliminary Round based on their high school race times in the 800 m, 1600 m, and 3200 m. Prediction accuracies of the classification trees ranged from 60.0 to 76.6 percent. The models produced the most reliable estimates for predicting qualifiers in cross country, the 1500 m, and the 800 m for females and cross country, the 5000 m, and the 800 m for males. NCAA track & field coaches can use the results from this study as a guideline for recruiting decisions. Additionally, future studies can apply the methodological foundations of this research to predicting race performances set at different metrics, such as national meets in other countries or Olympic qualifications, from previous race data.
Real-time edge tracking using a tactile sensor
NASA Technical Reports Server (NTRS)
Berger, Alan D.; Volpe, Richard; Khosla, Pradeep K.
1989-01-01
Object recognition through the use of input from multiple sensors is an important aspect of an autonomous manipulation system. In tactile object recognition, it is necessary to determine the location and orientation of object edges and surfaces. A controller is proposed that utilizes a tactile sensor in the feedback loop of a manipulator to track along edges. In the control system, the data from the tactile sensor is first processed to find edges. The parameters of these edges are then used to generate a control signal to a hybrid controller. Theory is presented for tactile edge detection and an edge tracking controller. In addition, experimental verification of the edge tracking controller is presented.
Detecting multiple moving objects in crowded environments with coherent motion regions
Cheriyadat, Anil M.; Radke, Richard J.
2013-06-11
Coherent motion regions extend in time as well as space, enforcing consistency in detected objects over long time periods and making the algorithm robust to noisy or short point tracks. As a result of enforcing the constraint that selected coherent motion regions contain disjoint sets of tracks defined in a three-dimensional space including a time dimension. An algorithm operates directly on raw, unconditioned low-level feature point tracks, and minimizes a global measure of the coherent motion regions. At least one discrete moving object is identified in a time series of video images based on the trajectory similarity factors, which is a measure of a maximum distance between a pair of feature point tracks.
Robotic vehicle with multiple tracked mobility platforms
Salton, Jonathan R [Albuquerque, NM; Buttz, James H [Albuquerque, NM; Garretson, Justin [Albuquerque, NM; Hayward, David R [Wetmore, CO; Hobart, Clinton G [Albuquerque, NM; Deuel, Jr., Jamieson K.
2012-07-24
A robotic vehicle having two or more tracked mobility platforms that are mechanically linked together with a two-dimensional coupling, thereby forming a composite vehicle of increased mobility. The robotic vehicle is operative in hazardous environments and can be capable of semi-submersible operation. The robotic vehicle is capable of remote controlled operation via radio frequency and/or fiber optic communication link to a remote operator control unit. The tracks have a plurality of track-edge scallop cut-outs that allow the tracks to easily grab onto and roll across railroad tracks, especially when crossing the railroad tracks at an oblique angle.
Attention to Attributes and Objects in Working Memory
ERIC Educational Resources Information Center
Cowan, Nelson; Blume, Christopher L.; Saults, J. Scott
2013-01-01
It has been debated on the basis of change-detection procedures whether visual working memory is limited by the number of objects, task-relevant attributes within those objects, or bindings between attributes. This debate, however, has been hampered by several limitations, including the use of conditions that vary between studies and the absence…
Real-time model-based vision system for object acquisition and tracking
NASA Technical Reports Server (NTRS)
Wilcox, Brian; Gennery, Donald B.; Bon, Bruce; Litwin, Todd
1987-01-01
A machine vision system is described which is designed to acquire and track polyhedral objects moving and rotating in space by means of two or more cameras, programmable image-processing hardware, and a general-purpose computer for high-level functions. The image-processing hardware is capable of performing a large variety of operations on images and on image-like arrays of data. Acquisition utilizes image locations and velocities of the features extracted by the image-processing hardware to determine the three-dimensional position, orientation, velocity, and angular velocity of the object. Tracking correlates edges detected in the current image with edge locations predicted from an internal model of the object and its motion, continually updating velocity information to predict where edges should appear in future frames. With some 10 frames processed per second, real-time tracking is possible.
Color image processing and object tracking workstation
NASA Technical Reports Server (NTRS)
Klimek, Robert B.; Paulick, Michael J.
1992-01-01
A system is described for automatic and semiautomatic tracking of objects on film or video tape which was developed to meet the needs of the microgravity combustion and fluid science experiments at NASA Lewis. The system consists of individual hardware parts working under computer control to achieve a high degree of automation. The most important hardware parts include 16 mm film projector, a lens system, a video camera, an S-VHS tapedeck, a frame grabber, and some storage and output devices. Both the projector and tapedeck have a computer interface enabling remote control. Tracking software was developed to control the overall operation. In the automatic mode, the main tracking program controls the projector or the tapedeck frame incrementation, grabs a frame, processes it, locates the edge of the objects being tracked, and stores the coordinates in a file. This process is performed repeatedly until the last frame is reached. Three representative applications are described. These applications represent typical uses and include tracking the propagation of a flame front, tracking the movement of a liquid-gas interface with extremely poor visibility, and characterizing a diffusion flame according to color and shape.
Lapierre, Mark; Howe, Piers D. L.; Cropper, Simon J.
2013-01-01
Many tasks involve tracking multiple moving objects, or stimuli. Some require that individuals adapt to changing or unfamiliar conditions to be able to track well. This study explores processes involved in such adaptation through an investigation of the interaction of attention and memory during tracking. Previous research has shown that during tracking, attention operates independently to some degree in the left and right visual hemifields, due to putative anatomical constraints. It has been suggested that the degree of independence is related to the relative dominance of processes of attention versus processes of memory. Here we show that when individuals are trained to track a unique pattern of movement in one hemifield, that learning can be transferred to the opposite hemifield, without any evidence of hemifield independence. However, learning is not influenced by an explicit strategy of memorisation of brief periods of recognisable movement. The findings lend support to a role for implicit memory in overcoming putative anatomical constraints on the dynamic, distributed spatial allocation of attention involved in tracking multiple objects. PMID:24349555
Exhausting Attentional Tracking Resources with a Single Fast-Moving Object
ERIC Educational Resources Information Center
Holcombe, Alex O.; Chen, Wei-Ying
2012-01-01
Driving on a busy road, eluding a group of predators, or playing a team sport involves keeping track of multiple moving objects. In typical laboratory tasks, the number of visual targets that humans can track is about four. Three types of theories have been advanced to explain this limit. The fixed-limit theory posits a set number of attentional…
The artificial retina processor for track reconstruction at the LHC crossing rate
Abba, A.; Bedeschi, F.; Citterio, M.; ...
2015-03-16
We present results of an R&D study for a specialized processor capable of precisely reconstructing, in pixel detectors, hundreds of charged-particle tracks from high-energy collisions at 40 MHz rate. We apply a highly parallel pattern-recognition algorithm, inspired by studies of the processing of visual images by the brain as it happens in nature, and describe in detail an efficient hardware implementation in high-speed, high-bandwidth FPGA devices. This is the first detailed demonstration of reconstruction of offline-quality tracks at 40 MHz and makes the device suitable for processing Large Hadron Collider events at the full crossing frequency.
NASA Astrophysics Data System (ADS)
Gad, Mohamed A.; Elshehaly, Mai H.; Gračanin, Denis; Elmongui, Hicham G.
2018-02-01
This research presents a novel Trajectory-based Tracking Analyst (TTA) that can track and link spatiotemporally variable data from multiple sources. The proposed technique uses trajectory information to determine the positions of time-enabled and spatially variable scatter data at any given time through a combination of along trajectory adjustment and spatial interpolation. The TTA is applied in this research to track large spatiotemporal data of volcanic eruptions (acquired using multi-sensors) in the unsteady flow field of the atmosphere. The TTA enables tracking injections into the atmospheric flow field, the reconstruction of the spatiotemporally variable data at any desired time, and the spatiotemporal join of attribute data from multiple sources. In addition, we were able to create a smooth animation of the volcanic ash plume at interactive rates. The initial results indicate that the TTA can be applied to a wide range of multiple-source data.
Real-time multiple objects tracking on Raspberry-Pi-based smart embedded camera
NASA Astrophysics Data System (ADS)
Dziri, Aziz; Duranton, Marc; Chapuis, Roland
2016-07-01
Multiple-object tracking constitutes a major step in several computer vision applications, such as surveillance, advanced driver assistance systems, and automatic traffic monitoring. Because of the number of cameras used to cover a large area, these applications are constrained by the cost of each node, the power consumption, the robustness of the tracking, the processing time, and the ease of deployment of the system. To meet these challenges, the use of low-power and low-cost embedded vision platforms to achieve reliable tracking becomes essential in networks of cameras. We propose a tracking pipeline that is designed for fixed smart cameras and which can handle occlusions between objects. We show that the proposed pipeline reaches real-time processing on a low-cost embedded smart camera composed of a Raspberry-Pi board and a RaspiCam camera. The tracking quality and the processing speed obtained with the proposed pipeline are evaluated on publicly available datasets and compared to the state-of-the-art methods.
ERIC Educational Resources Information Center
Longman, Cai S.; Lavric, Aureliu; Monsell, Stephen
2013-01-01
Switching tasks prolongs response times, an effect reduced but not eliminated by active preparation. To explore the role of attentional selection of the relevant stimulus attribute in these task-switch costs, we measured eye fixations in participants cued to identify either a face or a letter displayed on its forehead. With only 200 ms between cue…
Fission foil detector calibrations with high energy protons
NASA Technical Reports Server (NTRS)
Benton, E. V.; Frank, A. L.
1995-01-01
Fission foil detectors (FFD's) are passive devices composed of heavy metal foils in contact with muscovite mica films. The heavy metal nuclei have significant cross sections for fission when irradiated with neutrons and protons. Each isotope is characterized by threshold energies for the fission reactions and particular energy-dependent cross sections. In the FFD's, fission fragments produced by the reactions are emitted from the foils and create latent particle tracks in the adjacent mica films. When the films are processed surface tracks are formed which can be optically counted. The track densities are indications of the fluences and spectra of neutrons and/or protons. In the past, detection efficiencies have been calculated using the low energy neutron calibrated dosimeters and published fission cross sections for neutrons and protons. The problem is that the addition of a large kinetic energy to the (n,nucleus) or (p,nucleus) reaction could increase the energies and ranges of emitted fission fragments and increase the detector sensitivity as compared with lower energy neutron calibrations. High energy calibrations are the only method of resolving the uncertainties in detector efficiencies. At high energies, either proton or neutron calibrations are sufficient since the cross section data show that the proton and neutron fission cross sections are approximately equal. High energy proton beams have been utilized (1.8 and 4.9 GeV, 80 and 140 MeV) for measuring the tracks of fission fragments emitted backward and forward.
Kalal, Zdenek; Mikolajczyk, Krystian; Matas, Jiri
2012-07-01
This paper investigates long-term tracking of unknown objects in a video stream. The object is defined by its location and extent in a single frame. In every frame that follows, the task is to determine the object's location and extent or indicate that the object is not present. We propose a novel tracking framework (TLD) that explicitly decomposes the long-term tracking task into tracking, learning, and detection. The tracker follows the object from frame to frame. The detector localizes all appearances that have been observed so far and corrects the tracker if necessary. The learning estimates the detector's errors and updates it to avoid these errors in the future. We study how to identify the detector's errors and learn from them. We develop a novel learning method (P-N learning) which estimates the errors by a pair of "experts": (1) P-expert estimates missed detections, and (2) N-expert estimates false alarms. The learning process is modeled as a discrete dynamical system and the conditions under which the learning guarantees improvement are found. We describe our real-time implementation of the TLD framework and the P-N learning. We carry out an extensive quantitative evaluation which shows a significant improvement over state-of-the-art approaches.
A simple and rapid method for high-resolution visualization of single-ion tracks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Omichi, Masaaki; Center for Collaborative Research, Anan National College of Technology, Anan, Tokushima 774-0017; Choi, Wookjin
2014-11-15
Prompt determination of spatial points of single-ion tracks plays a key role in high-energy particle induced-cancer therapy and gene/plant mutations. In this study, a simple method for the high-resolution visualization of single-ion tracks without etching was developed through the use of polyacrylic acid (PAA)-N, N’-methylene bisacrylamide (MBAAm) blend films. One of the steps of the proposed method includes exposure of the irradiated films to water vapor for several minutes. Water vapor was found to promote the cross-linking reaction of PAA and MBAAm to form a bulky cross-linked structure; the ion-track scars were detectable at a nanometer scale by atomic forcemore » microscopy. This study demonstrated that each scar is easily distinguishable, and the amount of generated radicals of the ion tracks can be estimated by measuring the height of the scars, even in highly dense ion tracks. This method is suitable for the visualization of the penumbra region in a single-ion track with a high spatial resolution of 50 nm, which is sufficiently small to confirm that a single ion hits a cell nucleus with a size ranging between 5 and 20 μm.« less
Modular Track System For Positioning Mobile Robots
NASA Technical Reports Server (NTRS)
Miller, Jeff
1995-01-01
Conceptual system for positioning mobile robotic manipulators on large main structure includes modular tracks and ancillary structures assembled easily along with main structure. System, called "tracked robotic location system" (TROLS), originally intended for application to platforms in outer space, but TROLS concept might also prove useful on Earth; for example, to position robots in factories and warehouses. T-cross-section rail keeps mobile robot on track. Bar codes mark locations along track. Each robot equipped with bar-code-recognizing circuitry so it quickly finds way to assigned location.
Conductive tracks of 30-MeV C60 clusters in doped and undoped tetrahedral amorphous carbon
NASA Astrophysics Data System (ADS)
Krauser, J.; Gehrke, H.-G.; Hofsäss, H.; Trautmann, C.; Weidinger, A.
2013-07-01
In insulating tetrahedral amorphous carbon (ta-C), the irradiation with 30-MeV C60 cluster ions leads to the formation of well conducting tracks. While electrical currents through individual tracks produced with monoatomic projectiles (e.g. Au or U) often exhibit rather large track to track fluctuations, C60 clusters are shown to generate highly conducting tracks with very narrow current distributions. Additionally, all recorded current-voltage curves show linear characteristics. These findings are attributed to the large specific energy loss dE/dx of the 30-MeV C60 clusters. We also investigated C60 tracks in ta-C films which were slightly doped with B, N or Fe during film growth. Doping apparently increases the ion track conductivity. However, at the same time the insulating characteristics of the pristine ta-C film can be reduced. The present C60 results are compared with data from earlier experiments with monoatomic heavy ion beams. The investigations were performed by means of atomic force microscopy including temperature dependent conductivity measurements of single ion tracks.
Trajectory Specification for High-Capacity Air Traffic Control
NASA Technical Reports Server (NTRS)
Paielli, Russell A.
2004-01-01
In the current air traffic management system, the fundamental limitation on airspace capacity is the cognitive ability of human air traffic controllers to maintain safe separation with high reliability. The doubling or tripling of airspace capacity that will be needed over the next couple of decades will require that tactical separation be at least partially automated. Standardized conflict-free four-dimensional trajectory assignment will be needed to accomplish that objective. A trajectory specification format based on the Extensible Markup Language is proposed for that purpose. This format can be used to downlink a trajectory request, which can then be checked on the ground for conflicts and approved or modified, if necessary, then uplinked as the assigned trajectory. The horizontal path is specified as a series of geodetic waypoints connected by great circles, and the great-circle segments are connected by turns of specified radius. Vertical profiles for climb and descent are specified as low-order polynomial functions of along-track position, which is itself specified as a function of time. Flight technical error tolerances in the along-track, cross-track, and vertical axes define a bounding space around the reference trajectory, and conformance will guarantee the required separation for a period of time known as the conflict time horizon. An important safety benefit of this regimen is that the traffic will be able to fly free of conflicts for at least several minutes even if all ground systems and the entire communication infrastructure fail. Periodic updates in the along-track axis will adjust for errors in the predicted along-track winds.
NASA Astrophysics Data System (ADS)
Liu, Zhixiang; Xing, Tingwen; Jiang, Yadong; Lv, Baobin
2018-02-01
A two-dimensional (2-D) shearing interferometer based on an amplitude chessboard grating was designed to measure the wavefront aberration of a high numerical-aperture (NA) objective. Chessboard gratings offer better diffraction efficiencies and fewer disturbing diffraction orders than traditional cross gratings. The wavefront aberration of the tested objective was retrieved from the shearing interferogram using the Fourier transform and differential Zernike polynomial-fitting methods. Grating manufacturing errors, including the duty-cycle and pattern-deviation errors, were analyzed with the Fourier transform method. Then, according to the relation between the spherical pupil and planar detector coordinates, the influence of the distortion of the pupil coordinates was simulated. Finally, the systematic error attributable to grating alignment errors was deduced through the geometrical ray-tracing method. Experimental results indicate that the measuring repeatability (3σ) of the wavefront aberration of an objective with NA 0.4 was 3.4 mλ. The systematic-error results were consistent with previous analyses. Thus, the correct wavefront aberration can be obtained after calibration.
Photochemical grid model implementation and application of ...
For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3) concentrations. Source-based apportionment techniques implemented in photochemical grid models track sources through the physical and chemical processes important to the formation and transport of air pollutants. Photochemical model source apportionment has been used to track source impacts of specific sources, groups of sources (sectors), sources in specific geographic areas, and stratospheric and lateral boundary inflow on O3. The implementation and application of a source apportionment technique for O3 and its precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), for the Community Multiscale Air Quality (CMAQ) model are described here. The Integrated Source Apportionment Method (ISAM) O3 approach is a hybrid of source apportionment and source sensitivity in that O3 production is attributed to precursor sources based on O3 formation regime (e.g., for a NOx-sensitive regime, O3 is apportioned to participating NOx emissions). This implementation is illustrated by tracking multiple emissions source sectors and lateral boundary inflow. NOx, VOC, and O3 attribution to tracked sectors in the application are consistent with spatial and temporal patterns of precursor emissions. The O3 ISAM implementation is further evaluated through comparisons of apportioned am
Trajectory Control of Rendezvous with Maneuver Target Spacecraft
NASA Technical Reports Server (NTRS)
Zhou, Zhinqiang
2012-01-01
In this paper, a nonlinear trajectory control algorithm of rendezvous with maneuvering target spacecraft is presented. The disturbance forces on the chaser and target spacecraft and the thrust forces on the chaser spacecraft are considered in the analysis. The control algorithm developed in this paper uses the relative distance and relative velocity between the target and chaser spacecraft as the inputs. A general formula of reference relative trajectory of the chaser spacecraft to the target spacecraft is developed and applied to four different proximity maneuvers, which are in-track circling, cross-track circling, in-track spiral rendezvous and cross-track spiral rendezvous. The closed-loop differential equations of the proximity relative motion with the control algorithm are derived. It is proven in the paper that the tracking errors between the commanded relative trajectory and the actual relative trajectory are bounded within a constant region determined by the control gains. The prediction of the tracking errors is obtained. Design examples are provided to show the implementation of the control algorithm. The simulation results show that the actual relative trajectory tracks the commanded relative trajectory tightly. The predicted tracking errors match those calculated in the simulation results. The control algorithm developed in this paper can also be applied to interception of maneuver target spacecraft and relative trajectory control of spacecraft formation flying.
Enhancing Cognition with Video Games: A Multiple Game Training Study
Oei, Adam C.; Patterson, Michael D.
2013-01-01
Background Previous evidence points to a causal link between playing action video games and enhanced cognition and perception. However, benefits of playing other video games are under-investigated. We examined whether playing non-action games also improves cognition. Hence, we compared transfer effects of an action and other non-action types that required different cognitive demands. Methodology/Principal Findings We instructed 5 groups of non-gamer participants to play one game each on a mobile device (iPhone/iPod Touch) for one hour a day/five days a week over four weeks (20 hours). Games included action, spatial memory, match-3, hidden- object, and an agent-based life simulation. Participants performed four behavioral tasks before and after video game training to assess for transfer effects. Tasks included an attentional blink task, a spatial memory and visual search dual task, a visual filter memory task to assess for multiple object tracking and cognitive control, as well as a complex verbal span task. Action game playing eliminated attentional blink and improved cognitive control and multiple-object tracking. Match-3, spatial memory and hidden object games improved visual search performance while the latter two also improved spatial working memory. Complex verbal span improved after match-3 and action game training. Conclusion/Significance Cognitive improvements were not limited to action game training alone and different games enhanced different aspects of cognition. We conclude that training specific cognitive abilities frequently in a video game improves performance in tasks that share common underlying demands. Overall, these results suggest that many video game-related cognitive improvements may not be due to training of general broad cognitive systems such as executive attentional control, but instead due to frequent utilization of specific cognitive processes during game play. Thus, many video game training related improvements to cognition may be attributed to near-transfer effects. PMID:23516504
García-Fuster, M. Julia; Parsegian, Aram; Watson, Stanley J.; Akil, Huda; Flagel, Shelly B.
2018-01-01
Rationale Environmental challenges during adolescence, such as drug exposure, can cause enduring behavioral and molecular changes that contribute to life-long maladaptive behaviors, including addiction. Selectively bred high-responder (bHR) and low-responder (bLR) rats represent a unique model for assessing the long-term impact of adolescent environmental manipulations, as they inherently differ on a number of addiction-related traits. bHR rats are considered “addiction-prone”, whereas bLR rats are “addiction-resilient”, at least under baseline conditions. Moreover, relative to bLRs, bHR rats are more likely to attribute incentive motivational value to reward cues, or to “sign-track”. Objectives We utilized bHR and bLR rats to determine whether adolescent cocaine exposure can alter their inborn behavioral and neurobiological profiles, with a specific focus on Pavlovian conditioned approach behavior (i.e. sign- vs. goal-tracking) and hippocampal neurogenesis. Methods bHR and bLR rats were administered cocaine (15 mg/kg) or saline for 7 days during adolescence (postnatal day, PND 33–39) and subsequently tested for Pavlovian conditioned approach behavior in adulthood (PND 62–75), wherein an illuminated lever (conditioned stimulus) was followed by the response-independent delivery of a food pellet (unconditioned stimulus). Behaviors directed towards the lever and the food cup were recorded as sign- and goal-tracking, respectively. Hippocampal cell genesis was evaluated on PND 77 by immunohistochemistry. Results Adolescent cocaine exposure impaired hippocampal cell genesis (proliferation and survival) and enhanced the inherent propensity to goal-track in adult bLR, but not bHR, rats. Conclusions Adolescent cocaine exposure elicits long-lasting changes in stimulus-reward learning and enduring deficits in hippocampal neurogenesis selectively in adult bLR rats. PMID:28210781
Multi-object tracking of human spermatozoa
NASA Astrophysics Data System (ADS)
Sørensen, Lauge; Østergaard, Jakob; Johansen, Peter; de Bruijne, Marleen
2008-03-01
We propose a system for tracking of human spermatozoa in phase-contrast microscopy image sequences. One of the main aims of a computer-aided sperm analysis (CASA) system is to automatically assess sperm quality based on spermatozoa motility variables. In our case, the problem of assessing sperm quality is cast as a multi-object tracking problem, where the objects being tracked are the spermatozoa. The system combines a particle filter and Kalman filters for robust motion estimation of the spermatozoa tracks. Further, the combinatorial aspect of assigning observations to labels in the particle filter is formulated as a linear assignment problem solved using the Hungarian algorithm on a rectangular cost matrix, making the algorithm capable of handling missing or spurious observations. The costs are calculated using hidden Markov models that express the plausibility of an observation being the next position in the track history of the particle labels. Observations are extracted using a scale-space blob detector utilizing the fact that the spermatozoa appear as bright blobs in a phase-contrast microscope. The output of the system is the complete motion track of each of the spermatozoa. Based on these tracks, different CASA motility variables can be computed, for example curvilinear velocity or straight-line velocity. The performance of the system is tested on three different phase-contrast image sequences of varying complexity, both by visual inspection of the estimated spermatozoa tracks and by measuring the mean squared error (MSE) between the estimated spermatozoa tracks and manually annotated tracks, showing good agreement.
Tracking and people counting using Particle Filter Method
NASA Astrophysics Data System (ADS)
Sulistyaningrum, D. R.; Setiyono, B.; Rizky, M. S.
2018-03-01
In recent years, technology has developed quite rapidly, especially in the field of object tracking. Moreover, if the object under study is a person and the number of people a lot. The purpose of this research is to apply Particle Filter method for tracking and counting people in certain area. Tracking people will be rather difficult if there are some obstacles, one of which is occlusion. The stages of tracking and people counting scheme in this study include pre-processing, segmentation using Gaussian Mixture Model (GMM), tracking using particle filter, and counting based on centroid. The Particle Filter method uses the estimated motion included in the model used. The test results show that the tracking and people counting can be done well with an average accuracy of 89.33% and 77.33% respectively from six videos test data. In the process of tracking people, the results are good if there is partial occlusion and no occlusion
Real-Time Visual Tracking through Fusion Features
Ruan, Yang; Wei, Zhenzhong
2016-01-01
Due to their high-speed, correlation filters for object tracking have begun to receive increasing attention. Traditional object trackers based on correlation filters typically use a single type of feature. In this paper, we attempt to integrate multiple feature types to improve the performance, and we propose a new DD-HOG fusion feature that consists of discriminative descriptors (DDs) and histograms of oriented gradients (HOG). However, fusion features as multi-vector descriptors cannot be directly used in prior correlation filters. To overcome this difficulty, we propose a multi-vector correlation filter (MVCF) that can directly convolve with a multi-vector descriptor to obtain a single-channel response that indicates the location of an object. Experiments on the CVPR2013 tracking benchmark with the evaluation of state-of-the-art trackers show the effectiveness and speed of the proposed method. Moreover, we show that our MVCF tracker, which uses the DD-HOG descriptor, outperforms the structure-preserving object tracker (SPOT) in multi-object tracking because of its high-speed and ability to address heavy occlusion. PMID:27347951
2015-03-27
i.e., temporarily focusing on one object instead of wide area survey) or SOI collection on high interest objects (e.g., unidentified objects ...The Air Force Institute of Technology has spent the last seven years conducting research on orbit identification and object characterization of space... objects through the use of commercial-off-the-shelf hardware systems controlled via custom software routines, referred to simply as TeleTrak. Year
An Experiment on Salience as a Function of the Discriminatory Power of an Attribute.
ERIC Educational Resources Information Center
Finn, Michael S.
Carter's model of affective relations (1965) and Chaffee's research on cognitive discrepancies and communication (1959) are used to test the hypotheses that increasing an attribute's discriminatory power will increase attribute salience and that increasing the exclusiveness of an object's attributes will increase objective salience. The current…
Virtual network embedding in cross-domain network based on topology and resource attributes
NASA Astrophysics Data System (ADS)
Zhu, Lei; Zhang, Zhizhong; Feng, Linlin; Liu, Lilan
2018-03-01
Aiming at the network architecture ossification and the diversity of access technologies issues, this paper researches the cross-domain virtual network embedding algorithm. By analysing the topological attribute from the local and global perspective of nodes in the virtual network and the physical network, combined with the local network resource property, we rank the embedding priority of the nodes with PCA and TOPSIS methods. Besides, the link load distribution is considered. Above all, We proposed an cross-domain virtual network embedding algorithm based on topology and resource attributes. The simulation results depicts that our algorithm increases the acceptance rate of multi-domain virtual network requests, compared with the existing virtual network embedding algorithm.
Comparison of Procedures for Dual and Triple Closely Spaced Parallel Runways
NASA Technical Reports Server (NTRS)
Verma, Savita; Ballinger, Deborah; Subramanian Shobana; Kozon, Thomas
2012-01-01
A human-in-the-loop high fidelity flight simulation experiment was conducted, which investigated and compared breakout procedures for Very Closely Spaced Parallel Approaches (VCSPA) with two and three runways. To understand the feasibility, usability and human factors of two and three runway VCSPA, data were collected and analyzed on the dependent variables of breakout cross track error and pilot workload. Independent variables included number of runways, cause of breakout and location of breakout. Results indicated larger cross track error and higher workload using three runways as compared to 2-runway operations. Significant interaction effects involving breakout cause and breakout location were also observed. Across all conditions, cross track error values showed high levels of breakout trajectory accuracy and pilot workload remained manageable. Results suggest possible avenues of future adaptation for adopting these procedures (e.g., pilot training), while also showing potential promise of the concept.
NASA Technical Reports Server (NTRS)
Wilcox, Brian H.; Tso, Kam S.; Litwin, Todd E.; Hayati, Samad A.; Bon, Bruce B.
1991-01-01
Experimental robotic system semiautomatically grasps rotating object, stops rotation, and pulls object to rest in fixture. Based on combination of advanced techniques for sensing and control, constructed to test concepts for robotic recapture of spinning artificial satellites. Potential terrestrial applications for technology developed with help of system includes tracking and grasping of industrial parts on conveyor belts, tracking of vehicles and animals, and soft grasping of moving objects in general.
The role of visual attention in multiple object tracking: evidence from ERPs.
Doran, Matthew M; Hoffman, James E
2010-01-01
We examined the role of visual attention in the multiple object tracking (MOT) task by measuring the amplitude of the N1 component of the event-related potential (ERP) to probe flashes presented on targets, distractors, or empty background areas. We found evidence that visual attention enhances targets and suppresses distractors (Experiment 1 & 3). However, we also found that when tracking load was light (two targets and two distractors), accurate tracking could be carried out without any apparent contribution from the visual attention system (Experiment 2). Our results suggest that attentional selection during MOT is flexibly determined by task demands as well as tracking load and that visual attention may not always be necessary for accurate tracking.
Ye, Tao; Zhou, Fuqiang
2015-04-10
When imaged by detectors, space targets (including satellites and debris) and background stars have similar point-spread functions, and both objects appear to change as detectors track targets. Therefore, traditional tracking methods cannot separate targets from stars and cannot directly recognize targets in 2D images. Consequently, we propose an autonomous space target recognition and tracking approach using a star sensor technique and a Kalman filter (KF). A two-step method for subpixel-scale detection of star objects (including stars and targets) is developed, and the combination of the star sensor technique and a KF is used to track targets. The experimental results show that the proposed method is adequate for autonomously recognizing and tracking space targets.
Lung cancer incidence attributable to residential radon exposure in Alberta in 2012
Grundy, Anne; Brand, Kevin; Khandwala, Farah; Poirier, Abbey; Tamminen, Sierra; Friedenreich, Christine M.; Brenner, Darren R.
2017-01-01
Background: Radon is carcinogenic, and exposure to radon has been shown to increase the risk of lung cancer. The objective of this study was to quantify the proportion and number of lung cancer cases in Alberta in 2012 that could be attributed to residential radon exposure. Methods: We estimated the population attributable risk of lung cancer for residential radon using radon exposure data from the Cross-Canada Survey of Radon Concentrations in Homes from 2009-2011 and data on all-cause and lung cancer mortality from Statistics Canada from 2008-2012. We used cancer incidence data from the Alberta Cancer Registry for 2012 to estimate the total number of lung cancers attributable to residential radon exposure. Estimates were also stratified by sex and smoking status. Results: The mean geometric residential radon level in Alberta in 2011 was 71.0 Bq/m3 (geometric standard deviation 2.14). Overall, an estimated 16.6% (95% confidence interval 9.4%-29.8%) of lung cancers were attributable to radon exposure, corresponding to 324 excess attributable cancer cases. The estimated population attributable risk of lung cancer due to radon exposure was higher among those who had never smoked (24.8%) than among ever smokers (15.6%). However, since only about 10% of cases of lung cancer occur in nonsmokers, the estimated total number of excess cases was higher for ever smokers (274) than for never smokers (48). Interpretation: With about 17% of lung cancer cases in Alberta in 2012 attributable to residential radon exposure, exposure reduction has the potential to substantially reduce Alberta's lung cancer burden. As such, home radon testing and remediation techniques represent important cancer prevention strategies. PMID:28663187
The artificial retina for track reconstruction at the LHC crossing rate
NASA Astrophysics Data System (ADS)
Abba, A.; Bedeschi, F.; Citterio, M.; Caponio, F.; Cusimano, A.; Geraci, A.; Marino, P.; Morello, M. J.; Neri, N.; Punzi, G.; Piucci, A.; Ristori, L.; Spinella, F.; Stracka, S.; Tonelli, D.
2016-04-01
We present the results of an R&D study for a specialized processor capable of precisely reconstructing events with hundreds of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus suitable for processing LHC events at the full crossing frequency. For this purpose we design and test a massively parallel pattern-recognition algorithm, inspired to the current understanding of the mechanisms adopted by the primary visual cortex of mammals in the early stages of visual-information processing. The detailed geometry and charged-particle's activity of a large tracking detector are simulated and used to assess the performance of the artificial retina algorithm. We find that high-quality tracking in large detectors is possible with sub-microsecond latencies when the algorithm is implemented in modern, high-speed, high-bandwidth FPGA devices.
Lake, Amelia A; Adamson, Ashley J; Craigie, Angela M; Rugg-Gunn, Andrew J; Mathers, John C
2009-01-01
This paper describes the tracking of food intake from adolescence to adulthood according to location as an adult (at the time of the follow-up study) and gender. Additionally this paper explores factors associated with change in food intake. Two 3-day food diaries, demographic and socio-economic information were collected in 1980 and 2000 from the same 198 participants (81 male, 117 female). Foods consumed were assigned to the five categories in The Balance of Good Health (BGH) food model. The tracking of food intake was assessed using Pearson correlation analyses. In 2000 two questionnaires were completed. Demographic and key attributional factors, derived from closed and open-ended responses to the questionnaire, were compared with measured change using regression analysis. There was significant tracking of intake by food group from adolescence to adulthood according to location as an adult and gender. Eight combinations of descriptive variables and questionnaire factors were associated with change in intake of four of the five BGH food groups. Between adolescence and adulthood, dietary tracking is influenced by variables including gender and location. Attributions for change in food intake were associated with measured changes in food intake. In order to support healthier eating habits, it is important to be aware of factors contributing to changes in food intake, such as parental influences and perceived influences of time and work. Copyright 2009 S. Karger AG, Basel.
Attribute-based classification for zero-shot visual object categorization.
Lampert, Christoph H; Nickisch, Hannes; Harmeling, Stefan
2014-03-01
We study the problem of object recognition for categories for which we have no training examples, a task also called zero--data or zero-shot learning. This situation has hardly been studied in computer vision research, even though it occurs frequently; the world contains tens of thousands of different object classes, and image collections have been formed and suitably annotated for only a few of them. To tackle the problem, we introduce attribute-based classification: Objects are identified based on a high-level description that is phrased in terms of semantic attributes, such as the object's color or shape. Because the identification of each such property transcends the specific learning task at hand, the attribute classifiers can be prelearned independently, for example, from existing image data sets unrelated to the current task. Afterward, new classes can be detected based on their attribute representation, without the need for a new training phase. In this paper, we also introduce a new data set, Animals with Attributes, of over 30,000 images of 50 animal classes, annotated with 85 semantic attributes. Extensive experiments on this and two more data sets show that attribute-based classification indeed is able to categorize images without access to any training images of the target classes.
Infants Encode Phonetic Detail during Cross-Situational Word Learning
Escudero, Paola; Mulak, Karen E.; Vlach, Haley A.
2016-01-01
Infants often hear new words in the context of more than one candidate referent. In cross-situational word learning (XSWL), word-object mappings are determined by tracking co-occurrences of words and candidate referents across multiple learning events. Research demonstrates that infants can learn words in XSWL paradigms, suggesting that it is a viable model of real-world word learning. However, these studies have all presented infants with words that have no or minimal phonological overlap (e.g., BLICKET and GAX). Words often contain some degree of phonological overlap, and it is unknown whether infants can simultaneously encode fine phonological detail while learning words via XSWL. We tested 12-, 15-, 17-, and 20-month-olds’ XSWL of eight words that, when paired, formed non-minimal pairs (MPs; e.g., BON–DEET) or MPs (e.g., BON–TON, DEET–DIT). The results demonstrated that infants are able to learn word-object mappings and encode them with sufficient phonetic detail as to identify words in both non-minimal and MP contexts. Thus, this work suggests that infants are able to simultaneously discriminate phonetic differences between words and map words to referents in an implicit learning paradigm such as XSWL. PMID:27708605
An attentional drift diffusion model over binary-attribute choice.
Fisher, Geoffrey
2017-11-01
In order to make good decisions, individuals need to identify and properly integrate information about various attributes associated with a choice. Since choices are often complex and made rapidly, they are typically affected by contextual variables that are thought to influence how much attention is paid to different attributes. I propose a modification of the attentional drift-diffusion model, the binary-attribute attentional drift diffusion model (baDDM), which describes the choice process over simple binary-attribute choices and how it is affected by fluctuations in visual attention. Using an eye-tracking experiment, I find the baDDM makes accurate quantitative predictions about several key variables including choices, reaction times, and how these variables are correlated with attention to two attributes in an accept-reject decision. Furthermore, I estimate an attribute-based fixation bias that suggests attention to an attribute increases its subjective weight by 5%, while the unattended attribute's weight is decreased by 10%. Copyright © 2017 Elsevier B.V. All rights reserved.
An artificial retina processor for track reconstruction at the LHC crossing rate
Bedeschi, F.; Cenci, R.; Marino, P.; ...
2017-11-23
The goal of the INFN-RETINA R&D project is to develop and implement a computational methodology that allows to reconstruct events with a large number (> 100) of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus matching the requirements for processing LHC events at the full bunch-crossing frequency. Our approach relies on a parallel pattern-recognition algorithm, dubbed artificial retina, inspired by the early stages of image processing by the brain. In order to demonstrate that a track-processing system based on this algorithm is feasible, we built a sizable prototype of a tracking processor tuned to 3 000more » patterns, based on already existing readout boards equipped with Altera Stratix III FPGAs. The detailed geometry and charged-particle activity of a large tracking detector currently in operation are used to assess its performances. Here, we report on the test results with such a prototype.« less
An artificial retina processor for track reconstruction at the LHC crossing rate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bedeschi, F.; Cenci, R.; Marino, P.
The goal of the INFN-RETINA R&D project is to develop and implement a computational methodology that allows to reconstruct events with a large number (> 100) of charged-particle tracks in pixel and silicon strip detectors at 40 MHz, thus matching the requirements for processing LHC events at the full bunch-crossing frequency. Our approach relies on a parallel pattern-recognition algorithm, dubbed artificial retina, inspired by the early stages of image processing by the brain. In order to demonstrate that a track-processing system based on this algorithm is feasible, we built a sizable prototype of a tracking processor tuned to 3 000more » patterns, based on already existing readout boards equipped with Altera Stratix III FPGAs. The detailed geometry and charged-particle activity of a large tracking detector currently in operation are used to assess its performances. Here, we report on the test results with such a prototype.« less
Real-time visual tracking of less textured three-dimensional objects on mobile platforms
NASA Astrophysics Data System (ADS)
Seo, Byung-Kuk; Park, Jungsik; Park, Hanhoon; Park, Jong-Il
2012-12-01
Natural feature-based approaches are still challenging for mobile applications (e.g., mobile augmented reality), because they are feasible only in limited environments such as highly textured and planar scenes/objects, and they need powerful mobile hardware for fast and reliable tracking. In many cases where conventional approaches are not effective, three-dimensional (3-D) knowledge of target scenes would be beneficial. We present a well-established framework for real-time visual tracking of less textured 3-D objects on mobile platforms. Our framework is based on model-based tracking that efficiently exploits partially known 3-D scene knowledge such as object models and a background's distinctive geometric or photometric knowledge. Moreover, we elaborate on implementation in order to make it suitable for real-time vision processing on mobile hardware. The performance of the framework is tested and evaluated on recent commercially available smartphones, and its feasibility is shown by real-time demonstrations.
Object Tracking and Target Reacquisition Based on 3-D Range Data for Moving Vehicles
Lee, Jehoon; Lankton, Shawn; Tannenbaum, Allen
2013-01-01
In this paper, we propose an approach for tracking an object of interest based on 3-D range data. We employ particle filtering and active contours to simultaneously estimate the global motion of the object and its local deformations. The proposed algorithm takes advantage of range information to deal with the challenging (but common) situation in which the tracked object disappears from the image domain entirely and reappears later. To cope with this problem, a method based on principle component analysis (PCA) of shape information is proposed. In the proposed method, if the target disappears out of frame, shape similarity energy is used to detect target candidates that match a template shape learned online from previously observed frames. Thus, we require no a priori knowledge of the target’s shape. Experimental results show the practical applicability and robustness of the proposed algorithm in realistic tracking scenarios. PMID:21486717
Representing sentence information
NASA Astrophysics Data System (ADS)
Perkins, Walton A., III
1991-03-01
This paper describes a computer-oriented representation for sentence information. Whereas many Artificial Intelligence (AI) natural language systems start with a syntactic parse of a sentence into the linguist's components: noun, verb, adjective, preposition, etc., we argue that it is better to parse the input sentence into 'meaning' components: attribute, attribute value, object class, object instance, and relation. AI systems need a representation that will allow rapid storage and retrieval of information and convenient reasoning with that information. The attribute-of-object representation has proven useful for handling information in relational databases (which are well known for their efficiency in storage and retrieval) and for reasoning in knowledge- based systems. On the other hand, the linguist's syntactic representation of the works in sentences has not been shown to be useful for information handling and reasoning. We think it is an unnecessary and misleading intermediate form. Our sentence representation is semantic based in terms of attribute, attribute value, object class, object instance, and relation. Every sentence is segmented into one or more components with the form: 'attribute' of 'object' 'relation' 'attribute value'. Using only one format for all information gives the system simplicity and good performance as a RISC architecture does for hardware. The attribute-of-object representation is not new; it is used extensively in relational databases and knowledge-based systems. However, we will show that it can be used as a meaning representation for natural language sentences with minor extensions. In this paper we describe how a computer system can parse English sentences into this representation and generate English sentences from this representation. Much of this has been tested with computer implementation.
Creating objective and measurable postgraduate year 1 residency graduation requirements.
Starosta, Kaitlin; Davis, Susan L; Kenney, Rachel M; Peters, Michael; To, Long; Kalus, James S
2017-03-15
The process of developing objective and measurable postgraduate year 1 (PGY1) residency graduation requirements and a progress tracking system is described. The PGY1 residency accreditation standard requires that programs establish criteria that must be met by residents for successful completion of the program (i.e., graduation requirements), which should presumably be aligned with helping residents to achieve the purpose of residency training. In addition, programs must track a resident's progress toward fulfillment of residency goals and objectives. Defining graduation requirements and establishing the process for tracking residents' progress are left up to the discretion of the residency program. To help standardize resident performance assessments, leaders of an academic medical center-based PGY1 residency program developed graduation requirement criteria that are objective, measurable, and linked back to residency goals and objectives. A system for tracking resident progress relative to quarterly progress targets was instituted. Leaders also developed a focused, on-the-spot skills assessment termed "the Thunderdome," which was designed for objective evaluation of direct patient care skills. Quarterly data on residents' progress are used to update and customize each resident's training plan. Implementation of this system allowed seamless linkage of the training plan, the progress tracking system, and the specified graduation requirement criteria. PGY1 residency requirements that are objective, that are measurable, and that attempt to identify what skills the resident must demonstrate in order to graduate from the program were developed for use in our residency program. A system for tracking the residents' progress by comparing residents' performance to predetermined quarterly benchmarks was developed. Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.
Real-time moving objects detection and tracking from airborne infrared camera
NASA Astrophysics Data System (ADS)
Zingoni, Andrea; Diani, Marco; Corsini, Giovanni
2017-10-01
Detecting and tracking moving objects in real-time from an airborne infrared (IR) camera offers interesting possibilities in video surveillance, remote sensing and computer vision applications, such as monitoring large areas simultaneously, quickly changing the point of view on the scene and pursuing objects of interest. To fully exploit such a potential, versatile solutions are needed, but, in the literature, the majority of them works only under specific conditions about the considered scenario, the characteristics of the moving objects or the aircraft movements. In order to overcome these limitations, we propose a novel approach to the problem, based on the use of a cheap inertial navigation system (INS), mounted on the aircraft. To exploit jointly the information contained in the acquired video sequence and the data provided by the INS, a specific detection and tracking algorithm has been developed. It consists of three main stages performed iteratively on each acquired frame. The detection stage, in which a coarse detection map is computed, using a local statistic both fast to calculate and robust to noise and self-deletion of the targeted objects. The registration stage, in which the position of the detected objects is coherently reported on a common reference frame, by exploiting the INS data. The tracking stage, in which the steady objects are rejected, the moving objects are tracked, and an estimation of their future position is computed, to be used in the subsequent iteration. The algorithm has been tested on a large dataset of simulated IR video sequences, recreating different environments and different movements of the aircraft. Promising results have been obtained, both in terms of detection and false alarm rate, and in terms of accuracy in the estimation of position and velocity of the objects. In addition, for each frame, the detection and tracking map has been generated by the algorithm, before the acquisition of the subsequent frame, proving its capability to work in real-time.
Sarlegna, Fabrice R; Baud-Bovy, Gabriel; Danion, Frédéric
2010-08-01
When we manipulate an object, grip force is adjusted in anticipation of the mechanical consequences of hand motion (i.e., load force) to prevent the object from slipping. This predictive behavior is assumed to rely on an internal representation of the object dynamic properties, which would be elaborated via visual information before the object is grasped and via somatosensory feedback once the object is grasped. Here we examined this view by investigating the effect of delayed visual feedback during dextrous object manipulation. Adult participants manually tracked a sinusoidal target by oscillating a handheld object whose current position was displayed as a cursor on a screen along with the visual target. A delay was introduced between actual object displacement and cursor motion. This delay was linearly increased (from 0 to 300 ms) and decreased within 2-min trials. As previously reported, delayed visual feedback altered performance in manual tracking. Importantly, although the physical properties of the object remained unchanged, delayed visual feedback altered the timing of grip force relative to load force by about 50 ms. Additional experiments showed that this effect was not due to task complexity nor to manual tracking. A model inspired by the behavior of mass-spring systems suggests that delayed visual feedback may have biased the representation of object dynamics. Overall, our findings support the idea that visual feedback of object motion can influence the predictive control of grip force even when the object is grasped.
Human emotions track changes in the acoustic environment
Ma, Weiyi; Thompson, William Forde
2015-01-01
Emotional responses to biologically significant events are essential for human survival. Do human emotions lawfully track changes in the acoustic environment? Here we report that changes in acoustic attributes that are well known to interact with human emotions in speech and music also trigger systematic emotional responses when they occur in environmental sounds, including sounds of human actions, animal calls, machinery, or natural phenomena, such as wind and rain. Three changes in acoustic attributes known to signal emotional states in speech and music were imposed upon 24 environmental sounds. Evaluations of stimuli indicated that human emotions track such changes in environmental sounds just as they do for speech and music. Such changes not only influenced evaluations of the sounds themselves, they also affected the way accompanying facial expressions were interpreted emotionally. The findings illustrate that human emotions are highly attuned to changes in the acoustic environment, and reignite a discussion of Charles Darwin’s hypothesis that speech and music originated from a common emotional signal system based on the imitation and modification of environmental sounds. PMID:26553987
AN/FSY-3 Space Fence System Support of Conjunction Assessment
NASA Astrophysics Data System (ADS)
Koltiska, M.; Du, H.; Prochoda, D.; Kelly, K.
2016-09-01
The Space Fence System is a ground-based space surveillance radar system designed to detect and track all objects in Low Earth Orbit the size of a softball or larger. The system detects many objects that are not currently in the catalog of satellites and space debris that is maintained by the US Air Force. In addition, it will also be capable of tracking many of the deep space objects in the catalog. By providing daily updates of the orbits of these new objects along with updates of most of the objects in the catalog, it will enhance Space Situational Awareness and significantly improve our ability to predict close approaches, aka conjunctions, of objects in space. With this additional capacity for tracking objects in space the Space Surveillance Network has significantly more resources for monitoring orbital debris, especially for debris that could collide with active satellites and other debris.
Portable Catapult Launcher For Small Aircraft
NASA Technical Reports Server (NTRS)
Rosenbaum, Bernard J. (Inventor); Petter, George E. (Inventor); Gessler, Joseph A. (Inventor); Hughes, Michael G. (Inventor)
2005-01-01
An apparatus for launching an aircraft having a multiplicity of interconnected elongated tracks of rigid material forming a track system and wherein each elongated track has a predetermined elongated track cross-sectional design, a winch system connected to the track system wherein the winch system has a variable mechanical advantage, one or more elongated elastic members wherein one end of each of the one or more elongated elastic members is adjustably connected to the track system, and a carrier slidably mounted to the track system wherein the canier is connected to the winch system and to the other end of each of the one or more elongated elastic members.
Portable catapult launcher for small aircraft
NASA Technical Reports Server (NTRS)
Rosenbaum, Bernard J. (Inventor); Petter, George E. (Inventor); Gessler, Joseph A. (Inventor); Hughes, Michael G. (Inventor)
2005-01-01
An apparatus for launching an aircraft having a multiplicity of interconnected elongated tracks of rigid material forming a track system and wherein each elongated track has a predetermined elongated track cross-sectional design, a winch system connected to the track system wherein the winch system has a variable mechanical advantage, one or more elongated elastic members wherein one end of each of the one or more elongated elastic members is adjustably connected to the track system, and a carrier slidably mounted to the track system wherein the carrier is connected to the winch system and to the other end of each of the one or more elongated elastic members.
Doyle, Michael P.; Morris, J. Glenn; Painter, John; Singh, Ruby; Tauxe, Robert V.; Taylor, Michael R.; Wong, Danilo M.A. Lo Fo
2005-01-01
Identification and prioritization of effective food safety interventions require an understanding of the relationship between food and pathogen from farm to consumption. Critical to this cause is food attribution, the capacity to attribute cases of foodborne disease to the food vehicle or other source responsible for illness. A wide variety of food attribution approaches and data are used around the world, including the analysis of outbreak data, case-control studies, microbial subtyping and source tracking methods, and expert judgment, among others. The Food Safety Research Consortium sponsored the Food Attribution Data Workshop in October 2003 to discuss the virtues and limitations of these approaches and to identify future options for collecting food attribution data in the United States. We summarize workshop discussions and identify challenges that affect progress in this critical component of a risk-based approach to improving food safety. PMID:16022770
Large scale tracking algorithms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hansen, Ross L.; Love, Joshua Alan; Melgaard, David Kennett
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 highermore » 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.« less
EVA Robotic Assistant Project: Platform Attitude Prediction
NASA Technical Reports Server (NTRS)
Nickels, Kevin M.
2003-01-01
The Robotic Systems Technology Branch is currently working on the development of an EVA Robotic Assistant under the sponsorship of the Surface Systems Thrust of the NASA Cross Enterprise Technology Development Program (CETDP). This will be a mobile robot that can follow a field geologist during planetary surface exploration, carry his tools and the samples that he collects, and provide video coverage of his activity. Prior experiments have shown that for such a robot to be useful it must be able to follow the geologist at walking speed over any terrain of interest. Geologically interesting terrain tends to be rough rather than smooth. The commercial mobile robot that was recently purchased as an initial testbed for the EVA Robotic Assistant Project, an ATRV Jr., is capable of faster than walking speed outside but it has no suspension. Its wheels with inflated rubber tires are attached to axles that are connected directly to the robot body. Any angular motion of the robot produced by driving over rough terrain will directly affect the pointing of the on-board stereo cameras. The resulting image motion is expected to make tracking of the geologist more difficult. This will either require the tracker to search a larger part of the image to find the target from frame to frame or to search mechanically in pan and tilt whenever the image motion is large enough to put the target outside the image in the next frame. This project consists of the design and implementation of a Kalman filter that combines the output of the angular rate sensors and linear accelerometers on the robot to estimate the motion of the robot base. The motion of the stereo camera pair mounted on the robot that results from this motion as the robot drives over rough terrain is then straightforward to compute. The estimates may then be used, for example, to command the robot s on-board pan-tilt unit to compensate for the camera motion induced by the base movement. This has been accomplished in two ways: first, a standalone head stabilizer has been implemented and second, the estimates have been used to influence the search algorithm of the stereo tracking algorithm. Studies of the image motion of a tracked object indicate that the image motion of objects is suppressed while the robot crossing rough terrain. This work expands the range of speed and surface roughness over which the robot should be able to track and follow a field geologist and accept arm gesture commands from the geologist.
Dynamic simulation of train-truck collision at level crossings
NASA Astrophysics Data System (ADS)
Ling, Liang; Guan, Qinghua; Dhanasekar, Manicka; Thambiratnam, David P.
2017-01-01
Trains crashing onto heavy road vehicles stuck across rail tracks are more likely occurrences at level crossings due to ongoing increase in the registration of heavy vehicles and these long heavy vehicles getting caught in traffic after partly crossing the boom gate; these incidents lead to significant financial losses and societal costs. This paper presents an investigation of the dynamic responses of trains under frontal collision on road trucks obliquely stuck on rail tracks at level crossings. This study builds a nonlinear three-dimensional multi-body dynamic model of a passenger train colliding with an obliquely stuck road truck on a ballasted track. The model is first benchmarked against several train dynamics packages and its predictions of the dynamic response and derailment potential are shown rational. A geometry-based derailment assessment criterion is applied to evaluate the derailment behaviour of the frontal obliquely impacted trains under different conditions. Sensitivities of several key influencing parameters, such as the train impact speed, the truck mass, the friction at truck tyres, the train-truck impact angle, the contact friction at the collision zone, the wheel/rail friction and the train suspension are reported.
Multiplicative mixing of object identity and image attributes in single inferior temporal neurons.
Ratan Murty, N Apurva; Arun, S P
2018-04-03
Object recognition is challenging because the same object can produce vastly different images, mixing signals related to its identity with signals due to its image attributes, such as size, position, rotation, etc. Previous studies have shown that both signals are present in high-level visual areas, but precisely how they are combined has remained unclear. One possibility is that neurons might encode identity and attribute signals multiplicatively so that each can be efficiently decoded without interference from the other. Here, we show that, in high-level visual cortex, responses of single neurons can be explained better as a product rather than a sum of tuning for object identity and tuning for image attributes. This subtle effect in single neurons produced substantially better population decoding of object identity and image attributes in the neural population as a whole. This property was absent both in low-level vision models and in deep neural networks. It was also unique to invariances: when tested with two-part objects, neural responses were explained better as a sum than as a product of part tuning. Taken together, our results indicate that signals requiring separate decoding, such as object identity and image attributes, are combined multiplicatively in IT neurons, whereas signals that require integration (such as parts in an object) are combined additively. Copyright © 2018 the Author(s). Published by PNAS.
Track Geometry Development : UMTA Urban Rail Supporting Technology Program
DOT National Transportation Integrated Search
1974-04-01
Measurement of transit system track geometry parameters, under normal operating conditions, is essential for planning and conducting an effective maintenance program. The pertinent parameters are profile, gage, alignment, and cross level. Present met...
Monocular Stereo Measurement Using High-Speed Catadioptric Tracking
Hu, Shaopeng; Matsumoto, Yuji; Takaki, Takeshi; Ishii, Idaku
2017-01-01
This paper presents a novel concept of real-time catadioptric stereo tracking using a single ultrafast mirror-drive pan-tilt active vision system that can simultaneously switch between hundreds of different views in a second. By accelerating video-shooting, computation, and actuation at the millisecond-granularity level for time-division multithreaded processing in ultrafast gaze control, the active vision system can function virtually as two or more tracking cameras with different views. It enables a single active vision system to act as virtual left and right pan-tilt cameras that can simultaneously shoot a pair of stereo images for the same object to be observed at arbitrary viewpoints by switching the direction of the mirrors of the active vision system frame by frame. We developed a monocular galvano-mirror-based stereo tracking system that can switch between 500 different views in a second, and it functions as a catadioptric active stereo with left and right pan-tilt tracking cameras that can virtually capture 8-bit color 512×512 images each operating at 250 fps to mechanically track a fast-moving object with a sufficient parallax for accurate 3D measurement. Several tracking experiments for moving objects in 3D space are described to demonstrate the performance of our monocular stereo tracking system. PMID:28792483
Suboptimal choice in rats: incentive salience attribution promotes maladaptive decision-making
Chow, Jonathan J; Smith, Aaron P; Wilson, A George; Zentall, Thomas R; Beckmann, Joshua S
2016-01-01
Stimuli that are more predictive of subsequent reward also function as better conditioned reinforcers. Moreover, stimuli attributed with incentive salience function as more robust conditioned reinforcers. Some theories have suggested that conditioned reinforcement plays an important role in promoting suboptimal choice behavior, like gambling. The present experiments examined how different stimuli, those attributed with incentive salience versus those without, can function in tandem with stimulus-reward predictive utility to promote maladaptive decision-making in rats. One group of rats had lights associated with goal-tracking as the reward-predictive stimuli and another had levers associated with sign-tracking as the reward-predictive stimuli. All rats were first trained on a choice procedure in which the expected value across both alternatives was equivalent but differed in their stimulus-reward predictive utility. Next, the expected value across both alternatives was systematically changed so that the alternative with greater stimulus-reward predictive utility was suboptimal in regard to primary reinforcement. The results demonstrate that in order to obtain suboptimal choice behavior, incentive salience alongside strong stimulus-reward predictive utility may be necessary; thus, maladaptive decision-making can be driven more by the value attributed to stimuli imbued with incentive salience that reliably predict a reward rather than the reward itself. PMID:27993692
Suboptimal choice in rats: Incentive salience attribution promotes maladaptive decision-making.
Chow, Jonathan J; Smith, Aaron P; Wilson, A George; Zentall, Thomas R; Beckmann, Joshua S
2017-03-01
Stimuli that are more predictive of subsequent reward also function as better conditioned reinforcers. Moreover, stimuli attributed with incentive salience function as more robust conditioned reinforcers. Some theories have suggested that conditioned reinforcement plays an important role in promoting suboptimal choice behavior, like gambling. The present experiments examined how different stimuli, those attributed with incentive salience versus those without, can function in tandem with stimulus-reward predictive utility to promote maladaptive decision-making in rats. One group of rats had lights associated with goal-tracking as the reward-predictive stimuli and another had levers associated with sign-tracking as the reward-predictive stimuli. All rats were first trained on a choice procedure in which the expected value across both alternatives was equivalent but differed in their stimulus-reward predictive utility. Next, the expected value across both alternatives was systematically changed so that the alternative with greater stimulus-reward predictive utility was suboptimal in regard to primary reinforcement. The results demonstrate that in order to obtain suboptimal choice behavior, incentive salience alongside strong stimulus-reward predictive utility may be necessary; thus, maladaptive decision-making can be driven more by the value attributed to stimuli imbued with incentive salience that reliably predict a reward rather than the reward itself. Copyright © 2016 Elsevier B.V. All rights reserved.
Siamese convolutional networks for tracking the spine motion
NASA Astrophysics Data System (ADS)
Liu, Yuan; Sui, Xiubao; Sun, Yicheng; Liu, Chengwei; Hu, Yong
2017-09-01
Deep learning models have demonstrated great success in various computer vision tasks such as image classification and object tracking. However, tracking the lumbar spine by digitalized video fluoroscopic imaging (DVFI), which can quantitatively analyze the motion mode of spine to diagnose lumbar instability, has not yet been well developed due to the lack of steady and robust tracking method. In this paper, we propose a novel visual tracking algorithm of the lumbar vertebra motion based on a Siamese convolutional neural network (CNN) model. We train a full-convolutional neural network offline to learn generic image features. The network is trained to learn a similarity function that compares the labeled target in the first frame with the candidate patches in the current frame. The similarity function returns a high score if the two images depict the same object. Once learned, the similarity function is used to track a previously unseen object without any adapting online. In the current frame, our tracker is performed by evaluating the candidate rotated patches sampled around the previous frame target position and presents a rotated bounding box to locate the predicted target precisely. Results indicate that the proposed tracking method can detect the lumbar vertebra steadily and robustly. Especially for images with low contrast and cluttered background, the presented tracker can still achieve good tracking performance. Further, the proposed algorithm operates at high speed for real time tracking.
Tracks detection from high-orbit space objects
NASA Astrophysics Data System (ADS)
Shumilov, Yu. P.; Vygon, V. G.; Grishin, E. A.; Konoplev, A. O.; Semichev, O. P.; Shargorodskii, V. D.
2017-05-01
The paper presents studies results of a complex algorithm for the detection of highly orbital space objects. Before the implementation of the algorithm, a series of frames with weak tracks of space objects, which can be discrete, is recorded. The algorithm includes pre-processing, classical for astronomy, consistent filtering of each frame and its threshold processing, shear transformation, median filtering of the transformed series of frames, repeated threshold processing and detection decision making. Modeling of space objects weak tracks on of the night starry sky real frames obtained in the regime of a stationary telescope was carried out. It is shown that the permeability of an optoelectronic device has increased by almost 2m.
Application of Multi-Hypothesis Sequential Monte Carlo for Breakup Analysis
NASA Astrophysics Data System (ADS)
Faber, W. R.; Zaidi, W.; Hussein, I. I.; Roscoe, C. W. T.; Wilkins, M. P.; Schumacher, P. W., Jr.
As more objects are launched into space, the potential for breakup events and space object collisions is ever increasing. These events create large clouds of debris that are extremely hazardous to space operations. Providing timely, accurate, and statistically meaningful Space Situational Awareness (SSA) data is crucial in order to protect assets and operations in space. The space object tracking problem, in general, is nonlinear in both state dynamics and observations, making it ill-suited to linear filtering techniques such as the Kalman filter. Additionally, given the multi-object, multi-scenario nature of the problem, space situational awareness requires multi-hypothesis tracking and management that is combinatorially challenging in nature. In practice, it is often seen that assumptions of underlying linearity and/or Gaussianity are used to provide tractable solutions to the multiple space object tracking problem. However, these assumptions are, at times, detrimental to tracking data and provide statistically inconsistent solutions. This paper details a tractable solution to the multiple space object tracking problem applicable to space object breakup events. Within this solution, simplifying assumptions of the underlying probability density function are relaxed and heuristic methods for hypothesis management are avoided. This is done by implementing Sequential Monte Carlo (SMC) methods for both nonlinear filtering as well as hypothesis management. This goal of this paper is to detail the solution and use it as a platform to discuss computational limitations that hinder proper analysis of large breakup events.
Phenomenal Permanence and the Development of Predictive Tracking in Infancy
ERIC Educational Resources Information Center
Bertenthal, Bennett I.; Longo, Matthew R.; Kenny, Sarah
2007-01-01
The perceived spatiotemporal continuity of objects depends on the way they appear and disappear as they move in the spatial layout. This study investigated whether infants' predictive tracking of a briefly occluded object is sensitive to the manner by which the object disappears and reappears. Five-, 7-, and 9-month-old infants were shown a ball…
Qin, Junping; Sun, Shiwen; Deng, Qingxu; Liu, Limin; Tian, Yonghong
2017-06-02
Object tracking and detection is one of the most significant research areas for wireless sensor networks. Existing indoor trajectory tracking schemes in wireless sensor networks are based on continuous localization and moving object data mining. Indoor trajectory tracking based on the received signal strength indicator ( RSSI ) has received increased attention because it has low cost and requires no special infrastructure. However, RSSI tracking introduces uncertainty because of the inaccuracies of measurement instruments and the irregularities (unstable, multipath, diffraction) of wireless signal transmissions in indoor environments. Heuristic information includes some key factors for trajectory tracking procedures. This paper proposes a novel trajectory tracking scheme based on Delaunay triangulation and heuristic information (TTDH). In this scheme, the entire field is divided into a series of triangular regions. The common side of adjacent triangular regions is regarded as a regional boundary. Our scheme detects heuristic information related to a moving object's trajectory, including boundaries and triangular regions. Then, the trajectory is formed by means of a dynamic time-warping position-fingerprint-matching algorithm with heuristic information constraints. Field experiments show that the average error distance of our scheme is less than 1.5 m, and that error does not accumulate among the regions.
Color Image Processing and Object Tracking System
NASA Technical Reports Server (NTRS)
Klimek, Robert B.; Wright, Ted W.; Sielken, Robert S.
1996-01-01
This report describes a personal computer based system for automatic and semiautomatic tracking of objects on film or video tape, developed to meet the needs of the Microgravity Combustion and Fluids Science Research Programs at the NASA Lewis Research Center. The system consists of individual hardware components working under computer control to achieve a high degree of automation. The most important hardware components include 16-mm and 35-mm film transports, a high resolution digital camera mounted on a x-y-z micro-positioning stage, an S-VHS tapedeck, an Hi8 tapedeck, video laserdisk, and a framegrabber. All of the image input devices are remotely controlled by a computer. Software was developed to integrate the overall operation of the system including device frame incrementation, grabbing of image frames, image processing of the object's neighborhood, locating the position of the object being tracked, and storing the coordinates in a file. This process is performed repeatedly until the last frame is reached. Several different tracking methods are supported. To illustrate the process, two representative applications of the system are described. These applications represent typical uses of the system and include tracking the propagation of a flame front and tracking the movement of a liquid-gas interface with extremely poor visibility.
Li, Bin; Sang, Jizhang; Zhang, Zhongping
2016-01-01
A critical requirement to achieve high efficiency of debris laser tracking is to have sufficiently accurate orbit predictions (OP) in both the pointing direction (better than 20 arc seconds) and distance from the tracking station to the debris objects, with the former more important than the latter because of the narrow laser beam. When the two line element (TLE) is used to provide the orbit predictions, the resultant pointing errors are usually on the order of tens to hundreds of arc seconds. In practice, therefore, angular observations of debris objects are first collected using an optical tracking sensor, and then used to guide the laser beam pointing to the objects. The manual guidance may cause interrupts to the laser tracking, and consequently loss of valuable laser tracking data. This paper presents a real-time orbit determination (OD) and prediction method to realize smooth and efficient debris laser tracking. The method uses TLE-computed positions and angles over a short-arc of less than 2 min as observations in an OD process where simplified force models are considered. After the OD convergence, the OP is performed from the last observation epoch to the end of the tracking pass. Simulation and real tracking data processing results show that the pointing prediction errors are usually less than 10″, and the distance errors less than 100 m, therefore, the prediction accuracy is sufficient for the blind laser tracking. PMID:27347958
A Framework for Assessing the Value of Investments in Nonclinical Prevention
Roehrig, Charles; Russo, Pamela
2015-01-01
We present a high-level framework to show the process by which an investment in primary prevention produces value. We define primary prevention broadly to include investments in any of the determinants of health. Although it builds on previously developed frameworks, ours incorporates several additional features. It distinguishes direct and upstream determinants of health, a distinction that can help identify, describe, and track the impact of a policy or program on health and health care costs. It recognizes multiple dimensions of value, including the need to establish the nonhealth value of investments whose objectives are not limited to improvements in health (and whose costs should not be attributed solely to the health benefits). Finally, it emphasizes the need to describe value from the perspectives of the multiple stakeholders that can influence such investments. PMID:26652216
A Framework for Assessing the Value of Investments in Nonclinical Prevention.
Miller, George; Roehrig, Charles; Russo, Pamela
2015-12-10
We present a high-level framework to show the process by which an investment in primary prevention produces value. We define primary prevention broadly to include investments in any of the determinants of health. Although it builds on previously developed frameworks, ours incorporates several additional features. It distinguishes direct and upstream determinants of health, a distinction that can help identify, describe, and track the impact of a policy or program on health and health care costs. It recognizes multiple dimensions of value, including the need to establish the nonhealth value of investments whose objectives are not limited to improvements in health (and whose costs should not be attributed solely to the health benefits). Finally, it emphasizes the need to describe value from the perspectives of the multiple stakeholders that can influence such investments.
Vila, Bernat; Oms, Oriol; Fondevilla, Víctor; Gaete, Rodrigo; Galobart, Àngel; Riera, Violeta; Canudo, José Ignacio
2013-01-01
A comprehensive review and study of the rich dinosaur track record of the Tremp Formation in the southern Pyrenees of Spain (Southwestern Europe) shows a unique succession of footprint localities prior to the end-Cretaceous mass extinction event. A description of some 30 new tracksites and data on sedimentary environments, track occurrence and preservation, ichnology and chronostratigraphy are provided. These new track localities represent various facies types within a diverse set of fluvial environments. The footprint discoveries mostly represent hadrosaurian and, less abundantly, to sauropod dinosaurs. The hadrosaur tracks are significantly smaller in size than, but morphologically similar to, those of North America and Asia and are attributable to the ichnogenus Hadrosauropodus. The track succession, with more than 40 distinct track levels, indicates that hadrosaur footprints in the Ibero-Armorican region occur predominantly in the late Maaastrichtian (at least above the early Maastrichtian–late Maastrichtian boundary). The highest abundance is found noticeably found in the late Maastrichtian, with tracks occurring in the C29r magnetochron, within about the latest 300,000 years of the Cretaceous. PMID:24019873
Do Hostile Attribution Biases in Children and Parents Predict Relationally Aggressive Behavior?
ERIC Educational Resources Information Center
Werner, Nicole E.
2012-01-01
Relatively little is understood about the role of hostile attributions in children's use of relational aggression with peers, or about the impact of family processes on children's attributions about ambiguous provocations. This cross-sectional study investigated associations among hostile attributions made by children, mothers, and fathers, and…
The spatial distribution and evolution characteristics of North Atlantic cyclones
NASA Astrophysics Data System (ADS)
Dacre, H.; Gray, S.
2009-09-01
Mid-latitude cyclones play a large role in determining the day-to-day weather conditions in western Europe through their associated wind and precipitation patterns. Thus, their typical spatial and evolution characteristics are of great interest to meteorologists, insurance and risk management companies. In this study a feature tracking algorithm is applied to a cyclone database produced using the Hewson-method of cyclone identification, based on low-level gradients of wet-bulb potential temperature, to produce a climatology of mid-latitude cyclones. The aim of this work is to compare the cyclone track and density statistics found in this study with previous climatologies and to determine reasons for any differences. This method is found to compare well with other cyclone identification methods; the north Atlantic storm track is reproduced along with the major regions of genesis. Differences are attributed to cyclone lifetime and strength thresholds, dataset resolution and cyclone identification and tracking methods. Previous work on cyclone development has been largely limited to case studies as opposed to analysis of climatological data, and does not distinguish between the different stages of cyclone evolution. The cyclone database used in this study allows cyclone characteristics to be tracked throughout the cyclone lifecycle. This enables the evaluation of the characteristics of cyclone evolution for systems forming in different genesis regions and a calculation of the spatial distribution and evolution of these characteristics in composite cyclones. It was found that most of the cyclones that cross western Europe originate in the east Atlantic where the baroclinicity and sea surface temperature gradients are weak compared to the west Atlantic. East Atlantic cyclones also have higher low-level relative vorticity and lower mean sea level pressure at their genesis point than west Atlantic cyclones. This is consistent with the hypothesis that they are secondary cyclones developing on the trailing fronts of pre-existing 'parent' cyclones. Furthermore, it was found that a higher proportion of east Atlantic cyclones are type C cyclones with strong upper-level forcing but weak low-level forcing suggesting that latent energy plays a more important role in their intensification than for west Atlantic cyclones.
The spatial distribution and evolution characteristics of North Atlantic cyclones
NASA Astrophysics Data System (ADS)
Dacre, H.; Gray, S.
2009-04-01
Mid-latitude cyclones play a large role in determining the day-to-day weather conditions in western Europe through their associated wind and precipitation patterns. Thus, their typical spatial and evolution characteristics are of great interest to meteorologists, insurance and risk management companies. In this study a feature tracking algorithm is applied to a cyclone database produced using the Hewson-method of cyclone identification, based on low-level gradients of wet-bulb potential temperature, to produce a climatology of mid-latitude cyclones. The aim of this work is to compare the cyclone track and density statistics found in this study with previous climatologies. This method is found to compare well with other cyclone identification methods; the north Atlantic storm track is reproduced along with the major regions of genesis. Differences are attributed to cyclone lifetime and strength thresholds, dataset resolution and cyclone identification and tracking methods. Previous work on cyclone development has been largely limited to case studies as opposed to analysis of climatological data, and does not distinguish between the different stages of cyclone evolution. The cyclone database used in this study allows cyclone characteristics to be tracked throughout the cyclone lifecycle. This enables the evaluation of the characteristics of cyclone evolution for systems forming in different genesis regions and a calculation of the spatial distribution and evolution of these characteristics in composite cyclones. It was found that most of the cyclones that cross western Europe originate in the east Atlantic where the baroclinicity and sea surface temperature gradients are weak compared to the west Atlantic. East Atlantic cyclones also have higher low-level relative vorticity and lower mean sea level pressure at their genesis point than west Atlantic cyclones. This is consistent with the hypothesis that they are secondary cyclones developing on the trailing fronts of pre-existing 'parent' cyclones. Furthermore, it was found that a higher proportion of east Atlantic cyclones are type C cyclones with strong upper-level forcing but weak low-level forcing suggesting that latent energy plays a more important role in their intensification than for west Atlantic cyclones.