Neural tracking of attended versus ignored speech is differentially affected by hearing loss.

PubMed

Petersen, Eline Borch; Wöstmann, Malte; Obleser, Jonas; Lunner, Thomas

2017-01-01

Hearing loss manifests as a reduced ability to understand speech, particularly in multitalker situations. In these situations, younger normal-hearing listeners' brains are known to track attended speech through phase-locking of neural activity to the slow-varying envelope of the speech. This study investigates how hearing loss, compensated by hearing aids, affects the neural tracking of the speech-onset envelope in elderly participants with varying degree of hearing loss (n = 27, 62-86 yr; hearing thresholds 11-73 dB hearing level). In an active listening task, a to-be-attended audiobook (signal) was presented either in quiet or against a competing to-be-ignored audiobook (noise) presented at three individualized signal-to-noise ratios (SNRs). The neural tracking of the to-be-attended and to-be-ignored speech was quantified through the cross-correlation of the electroencephalogram (EEG) and the temporal envelope of speech. We primarily investigated the effects of hearing loss and SNR on the neural envelope tracking. First, we found that elderly hearing-impaired listeners' neural responses reliably track the envelope of to-be-attended speech more than to-be-ignored speech. Second, hearing loss relates to the neural tracking of to-be-ignored speech, resulting in a weaker differential neural tracking of to-be-attended vs. to-be-ignored speech in listeners with worse hearing. Third, neural tracking of to-be-attended speech increased with decreasing background noise. Critically, the beneficial effect of reduced noise on neural speech tracking decreased with stronger hearing loss. In sum, our results show that a common sensorineural processing deficit, i.e., hearing loss, interacts with central attention mechanisms and reduces the differential tracking of attended and ignored speech. The present study investigates the effect of hearing loss in older listeners on the neural tracking of competing speech. Interestingly, we observed that whereas internal degradation (hearing loss) relates to the neural tracking of ignored speech, external sound degradation (ratio between attended and ignored speech; signal-to-noise ratio) relates to tracking of attended speech. This provides the first evidence for hearing loss affecting the ability to neurally track speech. Copyright © 2017 the American Physiological Society.

Advantages and challenges in automated apatite fission track counting

NASA Astrophysics Data System (ADS)

Enkelmann, E.; Ehlers, T. A.

2012-04-01

Fission track thermochronometer data are often a core element of modern tectonic and denudation studies. Soon after the development of the fission track methods interest emerged for the developed an automated counting procedure to replace the time consuming labor of counting fission tracks under the microscope. Automated track counting became feasible in recent years with increasing improvements in computer software and hardware. One such example used in this study is the commercial automated fission track counting procedure from Autoscan Systems Pty that has been highlighted through several venues. We conducted experiments that are designed to reliably and consistently test the ability of this fully automated counting system to recognize fission tracks in apatite and a muscovite external detector. Fission tracks were analyzed in samples with a step-wise increase in sample complexity. The first set of experiments used a large (mm-size) slice of Durango apatite cut parallel to the prism plane. Second, samples with 80-200 μm large apatite grains of Fish Canyon Tuff were analyzed. This second sample set is characterized by complexities often found in apatites in different rock types. In addition to the automated counting procedure, the same samples were also analyzed using conventional counting procedures. We found for all samples that the fully automated fission track counting procedure using the Autoscan System yields a larger scatter in the fission track densities measured compared to conventional (manual) track counting. This scatter typically resulted from the false identification of tracks due surface and mineralogical defects, regardless of the image filtering procedure used. Large differences between track densities analyzed with the automated counting persisted between different grains analyzed in one sample as well as between different samples. As a result of these differences a manual correction of the fully automated fission track counts is necessary for each individual surface area and grain counted. This manual correction procedure significantly increases (up to four times) the time required to analyze a sample with the automated counting procedure compared to the conventional approach.

Human-like object tracking and gaze estimation with PKD android

PubMed Central

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.

Tracking planets and moons: mechanisms of object tracking revealed with a new paradigm

PubMed Central

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

Feature-based interference from unattended visual field during attentional tracking in younger and older adults.

PubMed

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.

Visuomotor Tracking Ability of Young Adult Speakers.

ERIC Educational Resources Information Center

Moon, Jerald B.; And Others

1993-01-01

Twenty-five normal young adult speakers tracked sinusoidal and unpredictable target signals using lower lip and jaw movement and fundamental frequency modulation. Tracking accuracy varied as a function of target frequency and articulator used to track. Results show the potential of visuomotor tracking tasks in the assessment of speech articulatory…

Classification of Animal Movement Behavior through Residence in Space and Time.

PubMed

Torres, Leigh G; Orben, Rachael A; Tolkova, Irina; Thompson, David R

2017-01-01

Identification and classification of behavior states in animal movement data can be complex, temporally biased, time-intensive, scale-dependent, and unstandardized across studies and taxa. Large movement datasets are increasingly common and there is a need for efficient methods of data exploration that adjust to the individual variability of each track. We present the Residence in Space and Time (RST) method to classify behavior patterns in movement data based on the concept that behavior states can be partitioned by the amount of space and time occupied in an area of constant scale. Using normalized values of Residence Time and Residence Distance within a constant search radius, RST is able to differentiate behavior patterns that are time-intensive (e.g., rest), time & distance-intensive (e.g., area restricted search), and transit (short time and distance). We use grey-headed albatross (Thalassarche chrysostoma) GPS tracks to demonstrate RST's ability to classify behavior patterns and adjust to the inherent scale and individuality of each track. Next, we evaluate RST's ability to discriminate between behavior states relative to other classical movement metrics. We then temporally sub-sample albatross track data to illustrate RST's response to less resolved data. Finally, we evaluate RST's performance using datasets from four taxa with diverse ecology, functional scales, ecosystems, and data-types. We conclude that RST is a robust, rapid, and flexible method for detailed exploratory analysis and meta-analyses of behavioral states in animal movement data based on its ability to integrate distance and time measurements into one descriptive metric of behavior groupings. Given the increasing amount of animal movement data collected, it is timely and useful to implement a consistent metric of behavior classification to enable efficient and comparative analyses. Overall, the application of RST to objectively explore and compare behavior patterns in movement data can enhance our fine- and broad- scale understanding of animal movement ecology.

Global navigation satellite system receiver for weak signals under all dynamic conditions

NASA Astrophysics Data System (ADS)

Ziedan, Nesreen Ibrahim

The ability of the Global Navigation Satellite System (GNSS) receiver to work under weak signal and various dynamic conditions is required in some applications. For example, to provide a positioning capability in wireless devices, or orbit determination of Geostationary and high Earth orbit satellites. This dissertation develops Global Positioning System (GPS) receiver algorithms for such applications. Fifteen algorithms are developed for the GPS C/A signal. They cover all the receiver main functions, which include acquisition, fine acquisition, bit synchronization, code and carrier tracking, and navigation message decoding. They are integrated together, and they can be used in any software GPS receiver. They also can be modified to fit any other GPS or GNSS signals. The algorithms have new capabilities. The processing and memory requirements are considered in the design to allow the algorithms to fit the limited resources of some applications; they do not require any assisting information. Weak signals can be acquired in the presence of strong interfering signals and under high dynamic conditions. The fine acquisition, bit synchronization, and tracking algorithms are based on the Viterbi algorithm and Extended Kalman filter approaches. The tracking algorithms capabilities increase the time to lose lock. They have the ability to adaptively change the integration length and the code delay separation. More than one code delay separation can be used in the same time. Large tracking errors can be detected and then corrected by a re-initialization and an acquisition-like algorithms. Detecting the navigation message is needed to increase the coherent integration; decoding it is needed to calculate the navigation solution. The decoding algorithm utilizes the message structure to enable its decoding for signals with high Bit Error Rate. The algorithms are demonstrated using simulated GPS C/A code signals, and TCXO clocks. The results have shown the algorithms ability to reliably work with 15 dB-Hz signals and acceleration over 6 g.

ISS Asset Tracking Using SAW RFID Technology

NASA Technical Reports Server (NTRS)

Schellhase, Amy; Powers, Annie

2004-01-01

A team at the NASA Johnson Space Center (JSC) is undergoing final preparations to test Surface Acoustic Wave (SAW) Radio Frequency Identification (RFID) technology to track assets aboard the International Space Station (ISS). Currently, almost 10,000 U.S. items onboard the ISS are tracked within a database maintained by both the JSC ground teams and crew onboard the ISS. This barcode-based inventory management system has successfully tracked the location of 97% of the items onboard, but its accuracy is dependant on the crew to report hardware movements, taking valuable time away from science and other activities. With the addition of future modules, the volume of inventory to be tracked is expected to increase significantly. The first test of RFID technology on ISS, which will be conducted by the Expedition 16 crew later this year, will evaluate the ability of RFID technology to track consumable items. These consumables, which include office supplies and clothing, are regularly supplied to ISS and can be tagged on the ground. Automation will eliminate line-of-sight auditing requirements, directly saving crew time. This first step in automating an inventory tracking system will pave the way for future uses of RFID for inventory tracking in space. Not only are there immediate benefits for ISS applications, it is a crucial step to ensure efficient logistics support for future vehicles and exploration missions where resupplies are not readily available. Following a successful initial test, the team plans to execute additional tests for new technology, expanded operations concepts, and increased automation.

Sorting Black Students for Success and Failure: The Inequality of Ability Grouping and Tracking.

ERIC Educational Resources Information Center

Chunn, Eva Wells

1988-01-01

Reviews the determinants and selected consequences of academic sorting practices. Concludes that tracking and ability grouping disproportionately affects Black and low-income students by stereotyping them as less intelligent and less able to achieve, which in turn creates low teacher expectations. (FMW)

On the Wrong Track: How Tracking Is Associated with Dropping out of High School

ERIC Educational Resources Information Center

Werblow, Jacob; Urick, Angela; Duesbery, Luke

2013-01-01

Academic tracking has been shown to limit the quality of student instructional opportunities, decrease students' perceptions of their abilities, and negatively influence student achievement. These factors associated with academic tracking also may influence students in lower tracks to learn less and ultimately to drop out of high school. Few…

Adapting Stanford’s Chronic Disease Self-Management Program to Hawaii’s Multicultural Population

PubMed Central

Tomioka, Michiyo; Braun, Kathryn L.; Compton, Merlita; Tanoue, Leslie

2012-01-01

Purpose of the Study: Stanford’s Chronic Disease Self-Management Program (CDSMP) has been proven to increase patients’ ability to manage distress. We describe how we replicated CDSMP in Asian and Pacific Islander (API) communities. Design and Methods: We used the “track changes” tool to deconstruct CDSMP into its various components (e.g., recruitment and staffing) and the “adaptation traffic light” to identify allowable modifications to the original program. We monitored local leaders’ fidelity of delivery of CDSMP and tracked participants’ attendance, satisfaction, and 6-month outcomes. Results: Between July 2007 and February 2010, 584 completed a CDSMP workshop. Baseline and 6-month data were available for 422 (72%), including 53 Caucasians, 177 Asians, and 194 Pacific Islanders. All 3 groups realized significant decreases in social and role activity limitations and significant increases in communication with physicians. Asians and Pacific Islanders also realized significant increases in self-rated health and time spent engaging in stretching/strengthening exercise. Asians also reported significant reductions in health distress and self-reported physician visits and increases in time spent in aerobic exercise, ability to cope with symptoms, and self-efficacy. Implications: Our experience suggests that CDSMP can be modified for increased cultural appropriateness for API communities while maintaining the key components responsible for behavior change. PMID:21719630

Effect of visual distraction and auditory feedback on patient effort during robot-assisted movement training after stroke

PubMed Central

2011-01-01

Background Practicing arm and gait movements with robotic assistance after neurologic injury can help patients improve their movement ability, but patients sometimes reduce their effort during training in response to the assistance. Reduced effort has been hypothesized to diminish clinical outcomes of robotic training. To better understand patient slacking, we studied the role of visual distraction and auditory feedback in modulating patient effort during a common robot-assisted tracking task. Methods Fourteen participants with chronic left hemiparesis from stroke, five control participants with chronic right hemiparesis and fourteen non-impaired healthy control participants, tracked a visual target with their arms while receiving adaptive assistance from a robotic arm exoskeleton. We compared four practice conditions: the baseline tracking task alone; tracking while also performing a visual distracter task; tracking with the visual distracter and sound feedback; and tracking with sound feedback. For the distracter task, symbols were randomly displayed in the corners of the computer screen, and the participants were instructed to click a mouse button when a target symbol appeared. The sound feedback consisted of a repeating beep, with the frequency of repetition made to increase with increasing tracking error. Results Participants with stroke halved their effort and doubled their tracking error when performing the visual distracter task with their left hemiparetic arm. With sound feedback, however, these participants increased their effort and decreased their tracking error close to their baseline levels, while also performing the distracter task successfully. These effects were significantly smaller for the participants who used their non-paretic arm and for the participants without stroke. Conclusions Visual distraction decreased participants effort during a standard robot-assisted movement training task. This effect was greater for the hemiparetic arm, suggesting that the increased demands associated with controlling an affected arm make the motor system more prone to slack when distracted. Providing an alternate sensory channel for feedback, i.e., auditory feedback of tracking error, enabled the participants to simultaneously perform the tracking task and distracter task effectively. Thus, incorporating real-time auditory feedback of performance errors might improve clinical outcomes of robotic therapy systems. PMID:21513561

Stable isotope analyses of feather amino acids identify penguin migration strategies at ocean basin scales.

PubMed

Polito, Michael J; Hinke, Jefferson T; Hart, Tom; Santos, Mercedes; Houghton, Leah A; Thorrold, Simon R

2017-08-01

Identifying the at-sea distribution of wide-ranging marine predators is critical to understanding their ecology. Advances in electronic tracking devices and intrinsic biogeochemical markers have greatly improved our ability to track animal movements on ocean-wide scales. Here, we show that, in combination with direct tracking, stable carbon isotope analysis of essential amino acids in tail feathers provides the ability to track the movement patterns of two, wide-ranging penguin species over ocean basin scales. In addition, we use this isotopic approach across multiple breeding colonies in the Scotia Arc to evaluate migration trends at a regional scale that would be logistically challenging using direct tracking alone. © 2017 The Author(s).

Tracking performance under time sharing conditions with a digit processing task: A feedback control theory analysis. [attention sharing effect on operator performance

NASA Technical Reports Server (NTRS)

Gopher, D.; Wickens, C. D.

1975-01-01

A one dimensional compensatory tracking task and a digit processing reaction time task were combined in a three phase experiment designed to investigate tracking performance in time sharing. Adaptive techniques, elaborate feedback devices, and on line standardization procedures were used to adjust task difficulty to the ability of each individual subject and manipulate time sharing demands. Feedback control analysis techniques were employed in the description of tracking performance. The experimental results show that when the dynamics of a system are constrained, in such a manner that man machine system stability is no longer a major concern of the operator, he tends to adopt a first order control describing function, even with tracking systems of higher order. Attention diversion to a concurrent task leads to an increase in remnant level, or nonlinear power. This decrease in linearity is reflected both in the output magnitude spectra of the subjects, and in the linear fit of the amplitude ratio functions.

Optimal Appearance Model for Visual Tracking

PubMed Central

Wang, Yuru; Jiang, Longkui; Liu, Qiaoyuan; Yin, Minghao

2016-01-01

Many studies argue that integrating multiple cues in an adaptive way increases tracking performance. However, what is the definition of adaptiveness and how to realize it remains an open issue. On the premise that the model with optimal discriminative ability is also optimal for tracking the target, this work realizes adaptiveness and robustness through the optimization of multi-cue integration models. Specifically, based on prior knowledge and current observation, a set of discrete samples are generated to approximate the foreground and background distribution. With the goal of optimizing the classification margin, an objective function is defined, and the appearance model is optimized by introducing optimization algorithms. The proposed optimized appearance model framework is embedded into a particle filter for a field test, and it is demonstrated to be robust against various kinds of complex tracking conditions. This model is general and can be easily extended to other parameterized multi-cue models. PMID:26789639

Tracking and Inferring Spatial Rotation by Children and Great Apes

ERIC Educational Resources Information Center

Okamoto-Barth; Sanae; Call, Josep

2008-01-01

Finding hidden objects in space is a fundamental ability that has received considerable research attention from both a developmental and a comparative perspective. Tracking the rotational displacements of containers and hidden objects is a particularly challenging task. This study investigated the ability of 3-, 5-, 7-, and 9-year-old children and…

To Track or Not to Track?

ERIC Educational Resources Information Center

Hesson, Heather

2010-01-01

Background: This paper was written for a graduate level action research course at Muskingum University, located in New Concord, OH. Purpose: The purpose of this research was to determine which method of instruction best serves ALL high school students. Is it more advantageous to track ("ability group") students or not to track students…

Benefits and challenges to using DNA-based identification methods: An example study of larval fish from nearshore areas of Lake Superior

EPA Science Inventory

DNA-based identification methods could increase the ability of aquatic resource managers to track patterns of invasive species, especially for taxa that are difficult to identify morphologically. Nonetheless, use of DNA-based identification methods in aquatic surveys is still unc...

Adapting Stanford's Chronic Disease Self-Management Program to Hawaii's Multicultural Population

ERIC Educational Resources Information Center

Tomioka, Michiyo; Braun, Kathryn L.; Compton, Merlita; Tanoue, Leslie

2012-01-01

Purpose of the Study: Stanford's Chronic Disease Self-Management Program (CDSMP) has been proven to increase patients' ability to manage distress. We describe how we replicated CDSMP in Asian and Pacific Islander (API) communities. Design and Methods: We used the "track changes" tool to deconstruct CDSMP into its various components…

78 FR 55717 - TRENDnet, Inc.; Analysis of Proposed Consent Order To Aid Public Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-11

... Pennsylvania Avenue NW., Washington, DC 20580, either in person or by calling (202) 326- 2222. You can file a... interested persons. Comments received during this period will become part of the public record. After thirty..., increases consumers' susceptibility to physical tracking or stalking, and reduces consumers' ability to...

Optimized tracking of RF carriers with phase noise, including Pioneer 10 results

NASA Technical Reports Server (NTRS)

Vilnrotter, V. A.; Hurd, W. J.; Brown, D. H.

1987-01-01

The ability to track very weak signals from distant spacecraft is limited by the phase instabilities of the received signal and of the local oscillator employed by the receiver. These instabilities ultimately limit the minimum loop bandwidth that can be used in a phase-coherent receiver, and hence limit the ratio of received carrier power to noise spectral density which can be tracked phase coherently. A method is presented for near real time estimation of the received carrier phase and additive noise spectrum, and optimization of the phase locked loop bandwidth. The method was used with the breadboard Deep Space Network (DSN) Advanced Receiver to optimize tracking of very weak signals from the Pioneer 10 spacecraft, which is now more distant that the edge of the solar system. Tracking with bandwidths of 0.1 Hz to 1.0 Hz reduces tracking signal threshold and increases carrier loop signal to noise ratio (SNR) by 5 dB to 15 dB compared to the 3 Hz bandwidth of the receivers now used operationally in the DSN. This will enable the DSN to track Pioneer 10 until its power sources fails near the end of the century.

Pathways of Intergenerational Transmission of Advantages during Adolescence: Social Background, Cognitive Ability, and Educational Attainment.

PubMed

Schulz, Wiebke; Schunck, Reinhard; Diewald, Martin; Johnson, Wendy

2017-10-01

Educational attainment in adolescence is of paramount importance for attaining higher education and for shaping subsequent life chances. Sociological accounts focus on the role of differences in socioeconomic resources in intergenerational reproduction of educational inequalities. These often disregard the intergenerational transmission of cognitive ability and the importance of children's cognitive ability to educational attainment. Psychological perspectives stress the importance of cognitive ability for educational attainment but underemphasize potentially different roles of specific socioeconomic resources in shaping educational outcomes, as well as individual differences in cognitive ability. By integrating two strands of research, a clearer picture of the pathways linking the family of origin, cognitive ability, and early educational outcomes can be reached. Using the population-based TwinLife study in Germany, we investigated multidimensional pathways linking parental socioeconomic position to their children's cognitive ability and academic track attendance in the secondary school. The sample included twins (N = 4008), respectively ages 11 and 17, and siblings (N = 801). We observed strong genetic influences on cognitive ability, whereas shared environmental influences were much more important for academic tracking. In multilevel analyses, separate dimensions of socioeconomic resources influenced child cognitive ability, controlling parental cognitive ability. Controlling adolescent cognitive ability and parental cognitive ability, parental socioeconomic resources also directly affected track attendance. This indicated that it is crucial to investigate the intertwined influences on educational outcomes in adolescence of both cognitive ability and the characteristics of the family of origin.

Ethanol Exposure History and Alcoholic Reward Differentially Alter Dopamine Release in the Nucleus Accumbens to a Reward-Predictive Cue.

PubMed

Fiorenza, Amanda M; Shnitko, Tatiana A; Sullivan, Kaitlin M; Vemuru, Sudheer R; Gomez-A, Alexander; Esaki, Julie Y; Boettiger, Charlotte A; Da Cunha, Claudio; Robinson, Donita L

2018-06-01

Conditioned stimuli (CS) that predict reward delivery acquire the ability to induce phasic dopamine release in the nucleus accumbens (NAc). This dopamine release may facilitate conditioned approach behavior, which often manifests as approach to the site of reward delivery (called "goal-tracking") or to the CS itself (called "sign-tracking"). Previous research has linked sign-tracking in particular to impulsivity and drug self-administration, and addictive drugs may promote the expression of sign-tracking. Ethanol (EtOH) acutely promotes phasic release of dopamine in the accumbens, but it is unknown whether an alcoholic reward alters dopamine release to a CS. We hypothesized that Pavlovian conditioning with an alcoholic reward would increase dopamine release triggered by the CS and subsequent sign-tracking behavior. Moreover, we predicted that chronic intermittent EtOH (CIE) exposure would promote sign-tracking while acute administration of naltrexone (NTX) would reduce it. Rats received 14 doses of EtOH (3 to 5 g/kg, intragastric) or water followed by 6 days of Pavlovian conditioning training. Rewards were a chocolate solution with or without 10% (w/v) alcohol. We used fast-scan cyclic voltammetry to measure phasic dopamine release in the NAc core in response to the CS and the rewards. We also determined the effect of NTX (1 mg/kg, subcutaneous) on conditioned approach. Both CIE and alcoholic reward, individually but not together, associated with greater dopamine to the CS than control conditions. However, this increase in dopamine release was not linked to greater sign-tracking, as both CIE and alcoholic reward shifted conditioned approach from sign-tracking behavior to goal-tracking behavior. However, they both also increased sensitivity to NTX, which reduced goal-tracking behavior. While a history of EtOH exposure or alcoholic reward enhanced dopamine release to a CS, they did not promote sign-tracking under the current conditions. These findings are consistent with the interpretation that EtOH can stimulate conditioned approach, but indicate that the conditioned response may manifest as goal-tracking. Copyright © 2018 by the Research Society on Alcoholism.

Usability evaluation of low-cost virtual reality hand and arm rehabilitation games.

PubMed

Seo, Na Jin; Arun Kumar, Jayashree; Hur, Pilwon; Crocher, Vincent; Motawar, Binal; Lakshminarayanan, Kishor

2016-01-01

The emergence of lower-cost motion tracking devices enables home-based virtual reality rehabilitation activities and increased accessibility to patients. Currently, little documentation on patients' expectations for virtual reality rehabilitation is available. This study surveyed 10 people with stroke for their expectations of virtual reality rehabilitation games. This study also evaluated the usability of three lower-cost virtual reality rehabilitation games using a survey and House of Quality analysis. The games (kitchen, archery, and puzzle) were developed in the laboratory to encourage coordinated finger and arm movements. Lower-cost motion tracking devices, the P5 Glove and Microsoft Kinect, were used to record the movements. People with stroke were found to desire motivating and easy-to-use games with clinical insights and encouragement from therapists. The House of Quality analysis revealed that the games should be improved by obtaining evidence for clinical effectiveness, including clinical feedback regarding improving functional abilities, adapting the games to the user's changing functional ability, and improving usability of the motion-tracking devices. This study reports the expectations of people with stroke for rehabilitation games and usability analysis that can help guide development of future games.

Improving Accuracy and Relevance of Race/Ethnicity Data: Results of a Statewide Collaboration in Hawaii.

PubMed

Pellegrin, Karen L; Miyamura, Jill B; Ma, Carolyn; Taniguchi, Ronald

2016-01-01

Current race/ethnicity categories established by the U.S. Office of Management and Budget are neither reliable nor valid for understanding health disparities or for tracking improvements in this area. In Hawaii, statewide hospitals have collaborated to collect race/ethnicity data using a standardized method consistent with recommended practices that overcome the problems with the federal categories. The purpose of this observational study was to determine the impact of this collaboration on key measures of race/ethnicity documentation. After this collaborative effort, the number of standardized categories available across hospitals increased from 6 to 34, and the percent of inpatients with documented race/ethnicity increased from 88 to 96%. This improved standardized methodology is now the foundation for tracking population health indicators statewide and focusing quality improvement efforts. The approach used in Hawaii can serve as a model for other states and regions. Ultimately, the ability to standardize data collection methodology across states and regions will be needed to track improvements nationally.

Distributed cluster management techniques for unattended ground sensor networks

NASA Astrophysics Data System (ADS)

Essawy, Magdi A.; Stelzig, Chad A.; Bevington, James E.; Minor, Sharon

2005-05-01

Smart Sensor Networks are becoming important target detection and tracking tools. The challenging problems in such networks include the sensor fusion, data management and communication schemes. This work discusses techniques used to distribute sensor management and multi-target tracking responsibilities across an ad hoc, self-healing cluster of sensor nodes. Although miniaturized computing resources possess the ability to host complex tracking and data fusion algorithms, there still exist inherent bandwidth constraints on the RF channel. Therefore, special attention is placed on the reduction of node-to-node communications within the cluster by minimizing unsolicited messaging, and distributing the sensor fusion and tracking tasks onto local portions of the network. Several challenging problems are addressed in this work including track initialization and conflict resolution, track ownership handling, and communication control optimization. Emphasis is also placed on increasing the overall robustness of the sensor cluster through independent decision capabilities on all sensor nodes. Track initiation is performed using collaborative sensing within a neighborhood of sensor nodes, allowing each node to independently determine if initial track ownership should be assumed. This autonomous track initiation prevents the formation of duplicate tracks while eliminating the need for a central "management" node to assign tracking responsibilities. Track update is performed as an ownership node requests sensor reports from neighboring nodes based on track error covariance and the neighboring nodes geo-positional location. Track ownership is periodically recomputed using propagated track states to determine which sensing node provides the desired coverage characteristics. High fidelity multi-target simulation results are presented, indicating the distribution of sensor management and tracking capabilities to not only reduce communication bandwidth consumption, but to also simplify multi-target tracking within the cluster.

Emergency medicine resident crisis resource management ability: a simulation-based longitudinal study

PubMed Central

Clarke, Samuel; Horeczko, Timothy; Carlisle, Matthew; Barton, Joseph D.; Ng, Vivienne; Al-Somali, Sameerah; Bair, Aaron E.

2014-01-01

Background Simulation has been identified as a means of assessing resident physicians’ mastery of technical skills, but there is a lack of evidence for its utility in longitudinal assessments of residents’ non-technical clinical abilities. We evaluated the growth of crisis resource management (CRM) skills in the simulation setting using a validated tool, the Ottawa Crisis Resource Management Global Rating Scale (Ottawa GRS). We hypothesized that the Ottawa GRS would reflect progressive growth of CRM ability throughout residency. Methods Forty-five emergency medicine residents were tracked with annual simulation assessments between 2006 and 2011. We used mixed-methods repeated-measures regression analyses to evaluate elements of the Ottawa GRS by level of training to predict performance growth throughout a 3-year residency. Results Ottawa GRS scores increased over time, and the domains of leadership, problem solving, and resource utilization, in particular, were predictive of overall performance. There was a significant gain in all Ottawa GRS components between postgraduate years 1 and 2, but no significant difference in GRS performance between years 2 and 3. Conclusions In summary, CRM skills are progressive abilities, and simulation is a useful modality for tracking their development. Modification of this tool may be needed to assess advanced learners’ gains in performance. PMID:25499769

Improved power for characterizing longitudinal amyloid-β PET changes and evaluating amyloid-modifying treatments with a cerebral white matter reference region.

PubMed

Chen, Kewei; Roontiva, Auttawut; Thiyyagura, Pradeep; Lee, Wendy; Liu, Xiaofen; Ayutyanont, Napatkamon; Protas, Hillary; Luo, Ji Luo; Bauer, Robert; Reschke, Cole; Bandy, Daniel; Koeppe, Robert A; Fleisher, Adam S; Caselli, Richard J; Landau, Susan; Jagust, William J; Weiner, Michael W; Reiman, Eric M

2015-04-01

In this article, we describe an image analysis strategy with improved power for tracking longitudinal amyloid-β (Aβ) PET changes and evaluating Aβ-modifying treatments. Our aims were to compare the power of template-based cerebellar, pontine, and cerebral white matter reference regions to track 24-mo florbetapir standardized uptake value (SUV) ratio (SUVR) changes; to relate those changes to 24-mo clinical declines; and to evaluate Aβ-modifying treatments in Aβ-positive (Aβ+) and Aβ-negative (Aβ-) patients with probable Alzheimer dementia (pAD), in patients with mild cognitive impairment (MCI), in cognitively normal controls (NCs), and in cognitively normal apolipoprotein E4 (APOE4) carriers and noncarriers. We used baseline and follow-up (∼24 mo) florbetapir PET scans from 332 Aβ+ and Aβ- subjects participating in the multicenter Alzheimer's Disease Neuroimaging Initiative. Each of the proposed analyses included 31 pAD patients, 187 MCI patients, and 114 NCs. Cerebral-to-white matter, cerebellar, and pontine SUVRs were characterized in terms of their longitudinal variability; their power to track longitudinal fibrillar Aβ increases in Aβ+ and Aβ- subgroups and cognitively normal APOE4 carriers and noncarriers; the sample sizes needed to detect attenuated accumulation of or clearance of fibrillar Aβ accumulation in randomized clinical trials; and their ability to relate 24-mo fibrillar Aβ increases to clinical declines. As predicted, cerebral-to-white matter SUVR changes were significantly less variable and had significantly greater power to detect 24-mo fibrillar Aβ increases and evaluate Aβ-modifying treatment effects in Aβ+ pAD, MCI, and NC subjects and cognitively normal APOE4 carriers. They were also distinguished by the ability to detect significant associations between 24-mo Aβ increases and clinical declines. A cerebral white matter reference region may improve the power to track longitudinal fibrillar Aβ increases, to characterize their relationship to longitudinal clinical declines, and to evaluate Aβ-modifying treatments in randomized clinical trials. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Does Attending a Low-Achieving School Affect High-Performing Student Outcomes?

ERIC Educational Resources Information Center

Parsons, Eric

2016-01-01

Background: Ability tracking in K-12 education has been the subject of much research over the past decades, with proponents arguing that it allows for better instructional targeting and opponents countering that it has the potential to increase inequality. Despite the large volume of research on the topic, however, there is little consensus on the…

Evaluation of pyrolysis and arc tracking on candidate wire insulation designs for space applications

NASA Technical Reports Server (NTRS)

Stueber, Thomas J.; Hrovat, Kenneth

1994-01-01

The ability of wire insulation materials and constructions to resist arc tracking was determined and the damage caused by initial arcing and restrike events was assessed. Results of arc tracking tests on various insulation constructions are presented in view-graph format. Arc tracking tests conducted on Champlain, Filotex, and Teledyne Thermatics indicate the Filotex is least likely to arc track. Arc tracking occurs more readily in air than it does in vacuum.

Sub-pixel localisation of passive micro-coil fiducial markers in interventional MRI.

PubMed

Rea, Marc; McRobbie, Donald; Elhawary, Haytham; Tse, Zion T H; Lamperth, Michael; Young, Ian

2009-04-01

Electromechanical devices enable increased accuracy in surgical procedures, and the recent development of MRI-compatible mechatronics permits the use of MRI for real-time image guidance. Integrated imaging of resonant micro-coil fiducials provides an accurate method of tracking devices in a scanner with increased flexibility compared to gradient tracking. Here we report on the ability of ten different image-processing algorithms to track micro-coil fiducials with sub-pixel accuracy. Five algorithms: maximum pixel, barycentric weighting, linear interpolation, quadratic fitting and Gaussian fitting were applied both directly to the pixel intensity matrix and to the cross-correlation matrix obtained by 2D convolution with a reference image. Using images of a 3 mm fiducial marker and a pixel size of 1.1 mm, intensity linear interpolation, which calculates the position of the fiducial centre by interpolating the pixel data to find the fiducial edges, was found to give the best performance for minimal computing power; a maximum error of 0.22 mm was observed in fiducial localisation for displacements up to 40 mm. The inherent standard deviation of fiducial localisation was 0.04 mm. This work enables greater accuracy to be achieved in passive fiducial tracking.

Haptic control with environment force estimation for telesurgery.

PubMed

Bhattacharjee, Tapomayukh; Son, Hyoung Il; Lee, Doo Yong

2008-01-01

Success of telesurgical operations depends on better position tracking ability of the slave device. Improved position tracking of the slave device can lead to safer and less strenuous telesurgical operations. The two-channel force-position control architecture is widely used for better position tracking ability. This architecture requires force sensors for direct force feedback. Force sensors may not be a good choice in the telesurgical environment because of the inherent noise, and limitation in the deployable place and space. Hence, environment force estimation is developed using the concept of the robot function parameter matrix and a recursive least squares method. Simulation results show efficacy of the proposed method. The slave device successfully tracks the position of the master device, and the estimation error quickly becomes negligible.

The more often you see an object, the easier it becomes to track it

PubMed Central

Pinto, Yaïr; Howe, Piers D. L.; Cohen, Michael A.; Horowitz, Todd S.

2010-01-01

Is it easier to track objects that you have seen repeatedly? We compared repeated blocks, where identities were the same from trial to trial, to unrepeated blocks, where identities varied. People were better in tracking objects that they saw repeatedly. We tested four hypotheses to explain this repetition benefit. First, perhaps the repeated condition benefits from consistent mapping of identities to target and distractor roles. However, the repetition benefit persisted even when both the repeated and the unrepeated conditions used consistent mapping. Second, repetition might improve the ability to recover targets that have been lost, or swapped with distractors. However, we observed a larger repetition benefit for color-color conjunctions, which do not benefit from such error recovery processes, than for unique features, which do. Furthermore, a repetition benefit was observed even in the absence of distractors. Third, perhaps repetition frees up resources by reducing memory load. However, increasing memory load by masking identities during the motion phase reduced the repetition benefit. The fourth hypothesis is that repetition facilitates identity tracking, which in turn improves location tracking. This hypothesis is consistent with all our results. Thus, our data suggest that identity and location tracking share a common resource. PMID:20884469

Hierarchical State-Space Estimation of Leatherback Turtle Navigation Ability

PubMed Central

Mills Flemming, Joanna; Jonsen, Ian D.; Field, Christopher A.

2010-01-01

Remotely sensed tracking technology has revealed remarkable migration patterns that were previously unknown; however, models to optimally use such data have developed more slowly. Here, we present a hierarchical Bayes state-space framework that allows us to combine tracking data from a collection of animals and make inferences at both individual and broader levels. We formulate models that allow the navigation ability of animals to be estimated and demonstrate how information can be combined over many animals to allow improved estimation. We also show how formal hypothesis testing regarding navigation ability can easily be accomplished in this framework. Using Argos satellite tracking data from 14 leatherback turtles, 7 males and 7 females, during their southward migration from Nova Scotia, Canada, we find that the circle of confusion (the radius around an animal's location within which it is unable to determine its location precisely) is approximately 96 km. This estimate suggests that the turtles' navigation does not need to be highly accurate, especially if they are able to use more reliable cues as they near their destination. Moreover, for the 14 turtles examined, there is little evidence to suggest that male and female navigation abilities differ. Because of the minimal assumptions made about the movement process, our approach can be used to estimate and compare navigation ability for many migratory species that are able to carry electronic tracking devices. PMID:21203382

An Overview of the NASA Aviation Safety Program (AVSP) Systemwide Accident Prevention (SWAP) Human Performance Modeling (HPM) Element

NASA Technical Reports Server (NTRS)

Foyle, David C.; Goodman, Allen; Hooley, Becky L.

2003-01-01

An overview is provided of the Human Performance Modeling (HPM) element within the NASA Aviation Safety Program (AvSP). Two separate model development tracks for performance modeling of real-world aviation environments are described: the first focuses on the advancement of cognitive modeling tools for system design, while the second centers on a prescriptive engineering model of activity tracking for error detection and analysis. A progressive implementation strategy for both tracks is discussed in which increasingly more complex, safety-relevant applications are undertaken to extend the state-of-the-art, as well as to reveal potential human-system vulnerabilities in the aviation domain. Of particular interest is the ability to predict the precursors to error and to assess potential mitigation strategies associated with the operational use of future flight deck technologies.

Real-Time Visual Tracking through Fusion Features

PubMed Central

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

Tracking Three-Dimensional Fish Behavior with a New Marine Acoustic Telemetry System

NASA Technical Reports Server (NTRS)

Brosnan, Ian G.; McGarry, Louise P.; Greene, Charles H.; Steig, Tracey W.; Johnston, Samuel V.; Ehrenberg, John E.

2015-01-01

The persistent monitoring capability provided by acoustic telemetry systems allows us to study behavior, movement, and resource selection of mobile marine animals. Current marine acoustic telemetry systems are challenged by localization errors and limits in the number of animals that can be tracked simultaneously. We designed a new system to provide detection ranges of up to 1 km, to reduce localization errors to less than 1 m, and to increase to 500 the number of unique tags simultaneously tracked. The design builds on HTIs experience of more than a decade developing acoustic telemetry systems for freshwater environments. A field trial of the prototype system was conducted at the University of Washingtons Friday Harbor Marine Laboratory (Friday Harbor, WA). Copper rockfish (Sebastes caurinus) were selected for field trials of this new system because their high site-fidelity and small home ranges provide ample opportunity to track individual fish behavior while testing our ability to characterize the movements of a species of interest to management authorities.

Should medical students track former patients in the electronic health record? An emerging ethical conflict.

PubMed

Brisson, Gregory E; Neely, Kathy Johnson; Tyler, Patrick D; Barnard, Cynthia

2015-08-01

Medical students are increasingly using electronic health records (EHRs) in clerkships, and medical educators should seek opportunities to use this new technology to improve training. One such opportunity is the ability to "track" former patients in the EHR, defined as following up on patients in the EHR for educational purposes for a defined period of time after they have left one's direct care. This activity offers great promise in clinical training by enabling students to audit their diagnostic impressions and follow the clinical history of illness in a manner not possible in the era of paper charting. However, tracking raises important questions about the ethical use of protected health information, including concerns about compromising patient autonomy, resulting in a conflict between medical education and patient privacy. The authors offer critical analysis of arguments on both sides and discuss strategies to balance the ethical conflict by optimizing outcomes and mitigating harms. They observe that tracking improves training, thus offering long-lasting benefits to society, and is supported by the principle of distributive justice. They conclude that students should be permitted to track for educational purposes, but only with defined limits to safeguard patient autonomy, including obtaining permission from patients, having legitimate educational intent, and self-restricting review of records to those essential for training. Lastly, the authors observe that this conflict will become increasingly important with completion of the planned Nationwide Health Information Network and emphasize the need for national guidelines on tracking patients in an ethically appropriate manner.

Constraints on Multiple Object Tracking in Williams Syndrome: How Atypical Development Can Inform Theories of Visual Processing

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…

Can Tracking Improve Learning?

ERIC Educational Resources Information Center

Duflo, Esther; Dupas, Pascaline; Kremer, Michael

2009-01-01

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

An Adaptive INS-Aided PLL Tracking Method for GNSS Receivers in Harsh Environments.

PubMed

Cong, Li; Li, Xin; Jin, Tian; Yue, Song; Xue, Rui

2016-01-23

As the weak link in global navigation satellite system (GNSS) signal processing, the phase-locked loop (PLL) is easily influenced with frequent cycle slips and loss of lock as a result of higher vehicle dynamics and lower signal-to-noise ratios. With inertial navigation system (INS) aid, PLLs' tracking performance can be improved. However, for harsh environments with high dynamics and signal attenuation, the traditional INS-aided PLL with fixed loop parameters has some limitations to improve the tracking adaptability. In this paper, an adaptive INS-aided PLL capable of adjusting its noise bandwidth and coherent integration time has been proposed. Through theoretical analysis, the relation between INS-aided PLL phase tracking error and carrier to noise density ratio (C/N₀), vehicle dynamics, aiding information update time, noise bandwidth, and coherent integration time has been built. The relation formulae are used to choose the optimal integration time and bandwidth for a given application under the minimum tracking error criterion. Software and hardware simulation results verify the correctness of the theoretical analysis, and demonstrate that the adaptive tracking method can effectively improve the PLL tracking ability and integrated GNSS/INS navigation performance. For harsh environments, the tracking sensitivity is increased by 3 to 5 dB, velocity errors are decreased by 36% to 50% and position errors are decreased by 6% to 24% when compared with other INS-aided PLL methods.

Attempting to "Increase Intake from the Input": Attention and Word Learning in Children with Autism

ERIC Educational Resources Information Center

Tenenbaum, Elena J.; Amso, Dima; Righi, Giulia; Sheinkopf, Stephen J.

2017-01-01

Previous work has demonstrated that social attention is related to early language abilities. We explored whether we can facilitate word learning among children with autism by directing attention to areas of the scene that have been demonstrated as relevant for successful word learning. We tracked eye movements to faces and objects while children…

Dynamic postural control and associated attentional demands in contemporary dancers versus non-dancers

PubMed Central

Sirois-Leclerc, Geneviève; Remaud, Anthony

2017-01-01

Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1) as a stand-alone task, and concurrently with both 2) a simple reaction time task and 3) a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources. PMID:28323843

Dynamic postural control and associated attentional demands in contemporary dancers versus non-dancers.

PubMed

Sirois-Leclerc, Geneviève; Remaud, Anthony; Bilodeau, Martin

2017-01-01

Postural control is not a fully automatic process, but requires a certain level of attention, particularly as the difficulty of the postural task increases. This study aimed at testing whether experienced contemporary dancers, because of their specialized training involving the control of posture/balance, would present with a dual-task performance suggesting lesser attentional demands associated with dynamic postural control compared with non-dancers. Twenty dancers and 16 non-dancers performed a dynamic postural tracking task in both antero-posterior and side-to-side directions, while standing on a force platform. The postural task was performed, in turn, 1) as a stand-alone task, and concurrently with both 2) a simple reaction time task and 3) a choice reaction time task. Postural control performance was estimated through variables calculated from centre of pressure movements. Although no overall group difference was found in reaction time values, we found a better ability to control the side to side movements of the centre of pressure during the tracking task in dancers compared with non-dancers, which was dependent on the secondary task. This suggests that such increased ability is influenced by available attentional resources.

The Tracking Wars: State Reform Meets School Policy.

ERIC Educational Resources Information Center

Loveless, Tom

This book examines the reactions of schools in Massachusetts and California to policies that sought to persuade schools to abandon or reduce tracking--the practice of grouping students into classes by ability and organizing curriculum by level of difficulty. The text is divided into 8 chapters: (1) "Implementing Tracking Reform," which…

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…

Population trends influence species ability to track climate change

Treesearch

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...

Not Your Father's Shop Class: Bridging the Academic-Vocational Divide

ERIC Educational Resources Information Center

Rose, Mike

2014-01-01

When this author was in high school in the 1960s, the curriculum was split into three tracks: an academic or college-preparatory track, a general education track, and a vocational track. Upon entrance, students were placed in one of them based on their previous academic records or a measure of ability, typically an IQ score. From the beginning of…

A Framework for Measuring Low-Value Care.

PubMed

Miller, George; Rhyan, Corwin; Beaudin-Seiler, Beth; Hughes-Cromwick, Paul

2018-04-01

It has been estimated that more than 30% of health care spending in the United States is wasteful, and that low-value care, which drives up costs unnecessarily while increasing patient risk, is a significant component of wasteful spending. To address the need for an ability to measure the magnitude of low-value care nationwide, identify the clinical services that are the greatest contributors to waste, and track progress toward eliminating low-value use of these services. Such an ability could provide valuable input to the efforts of policymakers and health systems to improve efficiency. We reviewed existing methods that could contribute to measuring low-value care and developed an integrated framework that combines multiple methods to comprehensively estimate and track the magnitude and principal sources of clinical waste. We also identified a process and needed research for implementing the framework. A comprehensive methodology for measuring and tracking low-value care in the United States would provide an important contribution toward reducing waste. Implementation of the framework described in this article appears feasible, and the proposed research program will allow moving incrementally toward full implementation while providing a near-term capability for measuring low-value care that can be enhanced over time. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Piloting Changes to Changing Aircraft Dynamics: What Do Pilots Need to Know?

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.; Gregory, Irene M.

2011-01-01

An experiment was conducted to quantify the effects of changing dynamics on a subject s ability to track a signal in order to eventually model a pilot adapting to changing aircraft dynamics. The data will be used to identify primary aircraft dynamics variables that influence changes in pilot s response and produce a simplified pilot model that incorporates this relationship. Each run incorporated a different set of second-order aircraft dynamics representing short period transfer function pitch attitude response: damping ratio, frequency, gain, zero location, and time delay. The subject s ability to conduct the tracking task was the greatest source of root mean square error tracking variability. As for the aircraft dynamics, the factors that affected the subjects ability to conduct the tracking were the time delay, frequency, and zero location. In addition to creating a simplified pilot model, the results of the experiment can be utilized in an advisory capacity. A situation awareness/prediction aid based on the pilot behavior and aircraft dynamics may help tailor pilot s inputs more quickly so that PIO or an upset condition can be avoided.

Methods to Increase the Sensitivity of High Resolution Melting Single Nucleotide Polymorphism Genotyping in Malaria.

PubMed

Daniels, Rachel; Hamilton, Elizabeth J; Durfee, Katelyn; Ndiaye, Daouda; Wirth, Dyann F; Hartl, Daniel L; Volkman, Sarah K

2015-11-10

Despite decades of eradication efforts, malaria remains a global burden. Recent renewed interest in regional elimination and global eradication has been accompanied by increased genomic information about Plasmodium parasite species responsible for malaria, including characteristics of geographical populations as well as variations associated with reduced susceptibility to anti-malarial drugs. One common genetic variation, single-nucleotide polymorphisms (SNPs), offers attractive targets for parasite genotyping. These markers are useful not only for tracking drug resistance markers but also for tracking parasite populations using markers not under drug or other selective pressures. SNP genotyping methods offer the ability to track drug resistance as well as to fingerprint individual parasites for population surveillance, particularly in response to malaria control efforts in regions nearing elimination status. While informative SNPs have been identified that are agnostic to specific genotyping technologies, high-resolution melting (HRM) analysis is particularly suited to field-based studies. Compared to standard fluorescent-probe based methods that require individual SNPs in a single labeled probe and offer at best 10% sensitivity to detect SNPs in samples that contain multiple genomes (polygenomic), HRM offers 2-5% sensitivity. Modifications to HRM, such as blocked probes and asymmetric primer concentrations as well as optimization of amplification annealing temperatures to bias PCR towards amplification of the minor allele, further increase the sensitivity of HRM. While the sensitivity improvement depends on the specific assay, we have increased detection sensitivities to less than 1% of the minor allele. In regions approaching malaria eradication, early detection of emerging or imported drug resistance is essential for prompt response. Similarly, the ability to detect polygenomic infections and differentiate imported parasite types from cryptic local reservoirs can inform control programs. This manuscript describes modifications to high resolution melting technology that further increase its sensitivity to identify polygenomic infections in patient samples.

Impaired force control in writer's cramp showing a bilateral deficit in sensorimotor integration.

PubMed

Bleton, Jean-Pierre; Teremetz, Maxime; Vidailhet, Marie; Mesure, Serge; Maier, Marc A; Lindberg, Påvel G

2014-01-01

Abnormal cortical processing of sensory inputs has been found bilaterally in writer's cramp (WC). This study tested the hypothesis that patients with WC have an impaired ability to adjust grip forces according to visual and somatosensory cues in both hands. A unimanual visuomotor force-tracking task and a bimanual sense of effort force-matching task were performed by WC patients and healthy controls. In visuomotor tracking, WC patients showed increased error, greater variability, and longer release duration than controls. In the force-matching task, patients underestimated, whereas controls overestimated, the force applied in the other hand. Visuomotor tracking and force matching were equally impaired in both the symptomatic and nonsymptomatic hand in WC patients. This study provides evidence of bilaterally impaired grip-force control in WC, when using visual or sense of effort cues. This suggests a generalized subclinical deficit in sensorimotor integration in WC. Copyright © 2013 Movement Disorder Society.

Vehicle tracking for an evasive manoeuvres assistant using low-cost ultrasonic sensors.

PubMed

Jiménez, Felipe; Naranjo, José E; Gómez, Oscar; Anaya, José J

2014-11-28

Many driver assistance systems require knowledge of the vehicle environment. As these systems are increasing in complexity and performance, this knowledge of the environment needs to be more complete and reliable, so sensor fusion combining long, medium and short range sensors is now being used. This paper analyzes the feasibility of using ultrasonic sensors for low cost vehicle-positioning and tracking in the lane adjacent to the host vehicle in order to identify free areas around the vehicle and provide information to an automatic avoidance collision system that can perform autonomous braking and lane change manoeuvres. A laser scanner is used for the early detection of obstacles in the direction of travel while two ultrasonic sensors monitor the blind spot of the host vehicle. The results of tests on a test track demonstrate the ability of these sensors to accurately determine the kinematic variables of the obstacles encountered, despite a clear limitation in range.

On analyzing colour constancy approach for improving SURF detector performance

NASA Astrophysics Data System (ADS)

Zulkiey, Mohd Asyraf; Zaki, Wan Mimi Diyana Wan; Hussain, Aini; Mustafa, Mohd. Marzuki

2012-04-01

Robust key point detector plays a crucial role in obtaining a good tracking feature. The main challenge in outdoor tracking is the illumination change due to various reasons such as weather fluctuation and occlusion. This paper approaches the illumination change problem by transforming the input image through colour constancy algorithm before applying the SURF detector. Masked grey world approach is chosen because of its ability to perform well under local as well as global illumination change. Every image is transformed to imitate the canonical illuminant and Gaussian distribution is used to model the global change. The simulation results show that the average number of detected key points have increased by 69.92%. Moreover, the average of improved performance cases far out weight the degradation case where the former is improved by 215.23%. The approach is suitable for tracking implementation where sudden illumination occurs frequently and robust key point detection is needed.

Non-invasive assessment of the liver using imaging

NASA Astrophysics Data System (ADS)

Thorling Thompson, Camilla; Wang, Haolu; Liu, Xin; Liang, Xiaowen; Crawford, Darrell H.; Roberts, Michael S.

2016-12-01

Chronic liver disease causes 2,000 deaths in Australia per year and early diagnosis is crucial to avoid progression to cirrhosis and end stage liver disease. There is no ideal method to evaluate liver function. Blood tests and liver biopsies provide spot examinations and are unable to track changes in function quickly. Therefore better techniques are needed. Non-invasive imaging has the potential to extract increased information over a large sampling area, continuously tracking dynamic changes in liver function. This project aimed to study the ability of three imaging techniques, multiphoton and fluorescence lifetime imaging microscopy, infrared thermography and photoacoustic imaging, in measuring liver function. Collagen deposition was obvious in multiphoton and fluorescence lifetime imaging in fibrosis and cirrhosis and comparable to conventional histology. Infrared thermography revealed a significantly increased liver temperature in hepatocellular carcinoma. In addition, multiphoton and fluorescence lifetime imaging and photoacoustic imaging could both track uptake and excretion of indocyanine green in rat liver. These results prove that non-invasive imaging can extract crucial information about the liver continuously over time and has the potential to be translated into clinic in the assessment of liver disease.

Tracking Behavioral Progress within a Children's Mental Health System: The Vermont Community Adjustment Tracking System.

ERIC Educational Resources Information Center

Bruns, Eric J.; Burchard, John D.; Froelich, Peter; Yoe, James T.; Tighe, Theodore

1998-01-01

Describes the Vermont Community Adjustment Tracking System (VT-CATS), which utilizes four behavioral instruments to allow intensive, ongoing, and interpretable behavioral assessment of a service system's most challenging children and adolescents. Also explains the adjustment indicator checklists and the ability of VT-CATS to address agencies'…

The new approach for infrared target tracking based on the particle filter algorithm

NASA Astrophysics Data System (ADS)

Sun, Hang; Han, Hong-xia

2011-08-01

Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring, precision, and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection, the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure, but in order to capture the change of the state space, it need a certain amount of particles to ensure samples is enough, and this number will increase in accompany with dimension and increase exponentially, this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining", we expand the classic Mean Shift tracking framework .Based on the previous perspective, we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis, Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism, used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation, and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value .Last because of the gray and fusion target motion information, this approach also inhibit interference from the background, ultimately improve the stability and the real-time of the target track.

Sustained multifocal attentional enhancement of stimulus processing in early visual areas predicts tracking performance.

PubMed

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.

Grouping and trajectory storage in multiple object tracking: impairments due to common item motions.

PubMed

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.

Severe Multisensory Speech Integration Deficits in High-Functioning School-Aged Children with Autism Spectrum Disorder (ASD) and Their Resolution During Early Adolescence

PubMed Central

Foxe, John J.; Molholm, Sophie; Del Bene, Victor A.; Frey, Hans-Peter; Russo, Natalie N.; Blanco, Daniella; Saint-Amour, Dave; Ross, Lars A.

2015-01-01

Under noisy listening conditions, visualizing a speaker's articulations substantially improves speech intelligibility. This multisensory speech integration ability is crucial to effective communication, and the appropriate development of this capacity greatly impacts a child's ability to successfully navigate educational and social settings. Research shows that multisensory integration abilities continue developing late into childhood. The primary aim here was to track the development of these abilities in children with autism, since multisensory deficits are increasingly recognized as a component of the autism spectrum disorder (ASD) phenotype. The abilities of high-functioning ASD children (n = 84) to integrate seen and heard speech were assessed cross-sectionally, while environmental noise levels were systematically manipulated, comparing them with age-matched neurotypical children (n = 142). Severe integration deficits were uncovered in ASD, which were increasingly pronounced as background noise increased. These deficits were evident in school-aged ASD children (5–12 year olds), but were fully ameliorated in ASD children entering adolescence (13–15 year olds). The severity of multisensory deficits uncovered has important implications for educators and clinicians working in ASD. We consider the observation that the multisensory speech system recovers substantially in adolescence as an indication that it is likely amenable to intervention during earlier childhood, with potentially profound implications for the development of social communication abilities in ASD children. PMID:23985136

Railroad decision support tools for track maintenance.

DOT National Transportation Integrated Search

2016-01-01

North American railroads spend billions of dollars each year on track maintenance. With : expenditures of this level, incremental improvements in planning or execution of maintenance projects can result in either substantial savings or the ability to...

Tracking and Ability Grouping in Education.

ERIC Educational Resources Information Center

Drowatzky, John N.

1981-01-01

A look at identification, grouping, and instruction techniques, followed by an assessment of the legality of a properly administered tracking system and an enumeration of guidelines and due process procedures that must be followed. (Author/MLF)

Comparison of Predictable Smooth Ocular and Combined Eye-Head Tracking Behaviour in Patients with Lesions Affecting the Brainstem and Cerebellum

NASA Technical Reports Server (NTRS)

Grant, Michael P.; Leigh, R. John; Seidman, Scott H.; Riley, David E.; Hanna, Joseph P.

1992-01-01

We compared the ability of eight normal subjects and 15 patients with brainstem or cerebellar disease to follow a moving visual stimulus smoothly with either the eyes alone or with combined eye-head tracking. The visual stimulus was either a laser spot (horizontal and vertical planes) or a large rotating disc (torsional plane), which moved at one sinusoidal frequency for each subject. The visually enhanced Vestibulo-Ocular Reflex (VOR) was also measured in each plane. In the horizontal and vertical planes, we found that if tracking gain (gaze velocity/target velocity) for smooth pursuit was close to 1, the gain of combined eye-hand tracking was similar. If the tracking gain during smooth pursuit was less than about 0.7, combined eye-head tracking was usually superior. Most patients, irrespective of diagnosis, showed combined eye-head tracking that was superior to smooth pursuit; only two patients showed the converse. In the torsional plane, in which optokinetic responses were weak, combined eye-head tracking was much superior, and this was the case in both subjects and patients. We found that a linear model, in which an internal ocular tracking signal cancelled the VOR, could account for our findings in most normal subjects in the horizontal and vertical planes, but not in the torsional plane. The model failed to account for tracking behaviour in most patients in any plane, and suggested that the brain may use additional mechanisms to reduce the internal gain of the VOR during combined eye-head tracking. Our results confirm that certain patients who show impairment of smooth-pursuit eye movements preserve their ability to smoothly track a moving target with combined eye-head tracking.

The Influence of Subject Areas on Middle School Tracking Policies. Faculty Research Working Paper Series R94-19.

ERIC Educational Resources Information Center

Loveless, Tom

Grouping students by ability into courses with distinct curricula, or "tracking" as it is called in middle and high schools, has provoked a furious debate among educational scholars and practitioners. Research on tracking invariably characterizes the practice as a school-level, unitary phenomenon; schools are depicted as either tracked…

The Differential Effects of School Tracking on Psychometric Intelligence: Do Academic-Track Schools Make Students Smarter?

ERIC Educational Resources Information Center

Becker, Michael; Ludtke, Oliver; Trautwein, Ulrich; Koller, Olaf; Baumert, Jurgen

2012-01-01

Prior research has shown that quantity of schooling affects the development of intelligence in childhood and adolescence. However, it is still debated whether other aspects of schooling--such as ability tracking or, more generally, school quality--can also influence intelligence. In this study, the authors analyzed intelligence gains in academic-…

"My Skin Color Stops Me from Leading": Tracking, Identity, and Student Dynamics in a Racially Mixed School

ERIC Educational Resources Information Center

Modica, Marianne

2015-01-01

The practice of separating students according to ability level, also known as academic tracking, allows racially mixed schools to maintain segregated classrooms. This article examines the effects of academic tracking on the racial identity and educational opportunities of students at a mixed-race suburban charter school. Through five months of…

Tracking Control of Hysteretic Piezoelectric Actuator using Adaptive Rate-Dependent Controller.

PubMed

Tan, U-Xuan; Latt, Win Tun; Widjaja, Ferdinan; Shee, Cheng Yap; Riviere, Cameron N; Ang, Wei Tech

2009-03-16

With the increasing popularity of actuators involving smart materials like piezoelectric, control of such materials becomes important. The existence of the inherent hysteretic behavior hinders the tracking accuracy of the actuators. To make matters worse, the hysteretic behavior changes with rate. One of the suggested ways is to have a feedforward controller to linearize the relationship between the input and output. Thus, the hysteretic behavior of the actuator must first be modeled by sensing the relationship between the input voltage and output displacement. Unfortunately, the hysteretic behavior is dependent on individual actuator and also environmental conditions like temperature. It is troublesome and costly to model the hysteresis regularly. In addition, the hysteretic behavior of the actuators also changes with age. Most literature model the actuator using a cascade of rate-independent hysteresis operators and a dynamical system. However, the inertial dynamics of the structure is not the only contributing factor. A complete model will be complex. Thus, based on the studies done on the phenomenological hysteretic behavior with rate, this paper proposes an adaptive rate-dependent feedforward controller with Prandtl-Ishlinskii (PI) hysteresis operators for piezoelectric actuators. This adaptive controller is achieved by adapting the coefficients to manipulate the weights of the play operators. Actual experiments are conducted to demonstrate the effectiveness of the adaptive controller. The main contribution of this paper is its ability to perform tracking control of non-periodic motion and is illustrated with the tracking control ability of a couple of different non-periodic waveforms which were created by passing random numbers through a low pass filter with a cutoff frequency of 20Hz.

Natural regeneration processes in big sagebrush (Artemisia tridentata)

USGS Publications Warehouse

Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

2014-01-01

Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified and characterized the controls of big sagebrush seed production, germination, and establishment. The largest knowledge gaps and associated research needs include quiescence and dormancy of embryos and seedlings; variation in seed production and germination percentages; wet-thermal time model of germination; responses to frost events (including freezing/thawing of soils), CO2 concentration, and nutrients in combination with water availability; suitability of microsite vs. site conditions; competitive ability as well as seedling growth responses; and differences among subspecies and ecoregions. Potential impacts of climate change on big sagebrush regeneration could include that temperature increases may not have a large direct influence on regeneration due to the broad temperature optimum for regeneration, whereas indirect effects could include selection for populations with less stringent seed dormancy. Drier conditions will have direct negative effects on germination and seedling survival and could also lead to lighter seeds, which lowers germination success further. The short seed dispersal distance of big sagebrush may limit its tracking of suitable climate; whereas, the low competitive ability of big sagebrush seedlings may limit successful competition with species that track climate. An improved understanding of the ecology of big sagebrush regeneration should benefit resource management activities and increase the ability of land managers to anticipate global change impacts.

Improving multi-tasking ability through action videogames.

PubMed

Chiappe, Dan; Conger, Mark; Liao, Janet; Caldwell, J Lynn; Vu, Kim-Phuong L

2013-03-01

The present study examined whether action videogames can improve multi-tasking in high workload environments. Two groups with no action videogame experience were pre-tested using the Multi-Attribute Task Battery (MATB). It consists of two primary tasks; tracking and fuel management, and two secondary tasks; systems monitoring and communication. One group served as a control group, while a second played action videogames a minimum of 5 h a week for 10 weeks. Both groups returned for a post-assessment on the MATB. We found the videogame treatment enhanced performance on secondary tasks, without interfering with the primary tasks. Our results demonstrate action videogames can increase people's ability to take on additional tasks by increasing attentional capacity. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

SSC Engineering Analysis

NASA Technical Reports Server (NTRS)

Ryan, Harry; Junell, Justin; Albasini, Colby; O'Rourke, William; Le, Thang; Strain, Ted; Stiglets, Tim

2011-01-01

A package for the automation of the Engineering Analysis (EA) process at the Stennis Space Center has been customized. It provides the ability to assign and track analysis tasks electronically, and electronically route a task for approval. It now provides a mechanism to keep these analyses under configuration management. It also allows the analysis to be stored and linked to the engineering data that is needed to perform the analysis (drawings, etc.). PTC s (Parametric Technology Corp o ration) Windchill product was customized to allow the EA to be created, routed, and maintained under configuration management. Using Infoengine Tasks, JSP (JavaServer Pages), Javascript, a user interface was created within the Windchill product that allows users to create EAs. Not only does this interface allow users to create and track EAs, but it plugs directly into the out-ofthe- box ability to associate these analyses with other relevant engineering data such as drawings. Also, using the Windchill workflow tool, the Design and Data Management System (DDMS) team created an electronic routing process based on the manual/informal approval process. The team also added the ability for users to notify and track notifications to individuals about the EA. Prior to the Engineering Analysis creation, there was no electronic way of creating and tracking these analyses. There was also a feature that was added that would allow users to track/log e-mail notifications of the EA.

Artist concept of the STS-43 Tracking and Data Relay Satellite E (TDRS-E)

NASA Image and Video Library

1990-06-22

Artist concept shows the Tracking and Data Relay Satellite E (TDRS-E) augmenting a sophisticated TDRS system (TDRSS) communications network after deployment during STS-43 from Atlantis, Orbiter Vehicle (OV) 104. TDRS, built by TRW, will be placed in a geosynchronous orbit and after onorbit testing, which requires several weeks, will be designated TDRS-5. The communications satellite will replace TDRS-3 at 174 degrees West longitude. The backbone of NASA's space-to-ground communications, the TDRSs have increased NASA's ability to send and receive data to spacecraft in low-earth orbit to more than 85 percent of the time. Before TDRS, NASA relied solely on a system of ground stations that permitted communications only 15 percent of the time. Increased coverage has allowed onorbit repairs, live television broadcast from space and continuous dialogues between astronaut crews and ground control during critical periods such as Space Shuttle landings.

The Health Assessment Longitudinal File imperative: foundation for improving the health of the force.

PubMed

Kemper, Judith A; Donahue, Donald A; Harris, Judith S

2003-08-01

A smaller active duty force and an increased operational tempo have made the Reserve components (RC) essential elements in the accomplishment of the mission of the U.S. Army. One critical factor in meeting mission is maintaining the optimal health of each soldier. Baseline health data about the RC is currently not being collected, even though increasing numbers of reserve soldiers are being activated. The Annual Health Certification and Survey is being developed as a way to meet the RCs' statutory requirement for annual certification of health while at the same time generating and tracking baseline data on each reservist in a longitudinal health file, the Health Assessment Longitudinal File. This article discusses the Annual Health Certification Questionnaire/Health Assessment Longitudinal File, which will greatly enhance the Army's ability to accurately certify the health status of the RC and track health in relation to training, mission activities, and deployment.

The White Bear in the Classroom: On the Use of Thought Suppression When Stakes Are High and Pressure to Perform Increases

ERIC Educational Resources Information Center

Imhof, Margarete; Schulte-Jakubowski, Katja

2015-01-01

This study examined how students use volitional control of thoughts in a context of performance during the 3-year pre-college track in their high school program. A total of 142 students were surveyed on their ability to volitionally control potentially disruptive cognitions, on their perception of positive and negative mood, and how this is…

Impact of radio-frequency identification (RFID) technologies on the hospital supply chain: a literature review.

PubMed

Coustasse, Alberto; Tomblin, Shane; Slack, Chelsea

2013-01-01

Supply costs account for more than one-third of the average operating budget and constitute the second largest expenditure in hospitals. As hospitals have sought to reduce these costs, radio-frequency identification (RFID) technology has emerged as a solution. This study reviews existing literature to gauge the recent and potential impact and direction of the implementation of RFID in the hospital supply chain to determine current benefits and barriers of adoption. Findings show that the application of RFID to medical equipment and supplies tracking has resulted in efficiency increases in hospitals with lower costs and increased service quality. RFID technology can reduce costs, improve patient safety, and improve supply chain management effectiveness by increasing the ability to track and locate equipment, as well as monitoring theft prevention, distribution management, and patient billing. Despite ongoing RFID implementation in the hospital supply chain, barriers to widespread and rapid adoption include significant total expenditures, unclear return on investment, and competition with other strategic imperatives.

Impact of Radio-Frequency Identification (RFID) Technologies on the Hospital Supply Chain: A Literature Review

PubMed Central

Coustasse, Alberto; Tomblin, Shane; Slack, Chelsea

2013-01-01

Supply costs account for more than one-third of the average operating budget and constitute the second largest expenditure in hospitals. As hospitals have sought to reduce these costs, radio-frequency identification (RFID) technology has emerged as a solution. This study reviews existing literature to gauge the recent and potential impact and direction of the implementation of RFID in the hospital supply chain to determine current benefits and barriers of adoption. Findings show that the application of RFID to medical equipment and supplies tracking has resulted in efficiency increases in hospitals with lower costs and increased service quality. RFID technology can reduce costs, improve patient safety, and improve supply chain management effectiveness by increasing the ability to track and locate equipment, as well as monitoring theft prevention, distribution management, and patient billing. Despite ongoing RFID implementation in the hospital supply chain, barriers to widespread and rapid adoption include significant total expenditures, unclear return on investment, and competition with other strategic imperatives. PMID:24159272

Developmental Profiles for Multiple Object Tracking and Spatial Memory: Typically Developing Preschoolers and People with Williams Syndrome

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…

Commercial vehicle route tracking using video detection.

DOT National Transportation Integrated Search

2010-10-31

Interstate commercial vehicle traffic is a major factor in the life of any road surface. The ability to track : these vehicles and their routes through the state can provide valuable information to planning : activities. We propose a method using vid...

Effects of some motion sickness suppressants on tracking performance during angular accelerations.

DOT National Transportation Integrated Search

1982-10-01

The two studies reported here examined the influence of three established antimotion sickness drugs on tracking performance in static (stationary) and dynamic (angular acceleration) conditions and on visual fixation ability during motion. : In Study ...

Space and Time Resolved Detection of Platelet Activation and von Willebrand Factor Conformational Changes in Deep Suspensions.

PubMed

Biasetti, Jacopo; Sampath, Kaushik; Cortez, Angel; Azhir, Alaleh; Gilad, Assaf A; Kickler, Thomas S; Obser, Tobias; Ruggeri, Zaverio M; Katz, Joseph

2017-01-01

Tracking cells and proteins' phenotypic changes in deep suspensions is critical for the direct imaging of blood-related phenomena in in vitro replica of cardiovascular systems and blood-handling devices. This paper introduces fluorescence imaging techniques for space and time resolved detection of platelet activation, von Willebrand factor (VWF) conformational changes, and VWF-platelet interaction in deep suspensions. Labeled VWF, platelets, and VWF-platelet strands are suspended in deep cuvettes, illuminated, and imaged with a high-sensitivity EM-CCD camera, allowing detection using an exposure time of 1 ms. In-house postprocessing algorithms identify and track the moving signals. Recombinant VWF-eGFP (rVWF-eGFP) and VWF labeled with an FITC-conjugated polyclonal antibody are employed. Anti-P-Selectin FITC-conjugated antibodies and the calcium-sensitive probe Indo-1 are used to detect activated platelets. A positive correlation between the mean number of platelets detected per image and the percentage of activated platelets determined through flow cytometry is obtained, validating the technique. An increase in the number of rVWF-eGFP signals upon exposure to shear stress demonstrates the technique's ability to detect breakup of self-aggregates. VWF globular and unfolded conformations and self-aggregation are also observed. The ability to track the size and shape of VWF-platelet strands in space and time provides means to detect pro- and antithrombotic processes.

Using psilocybin to investigate the relationship between attention, working memory, and the serotonin 1A and 2A receptors.

PubMed

Carter, Olivia L; Burr, David C; Pettigrew, John D; Wallis, Guy M; Hasler, Felix; Vollenweider, Franz X

2005-10-01

Increasing evidence suggests a link between attention, working memory, serotonin (5-HT), and prefrontal cortex activity. In an attempt to tease out the relationship between these elements, this study tested the effects of the hallucinogenic mixed 5-HT1A/2A receptor agonist psilocybin alone and after pretreatment with the 5-HT2A antagonist ketanserin. Eight healthy human volunteers were tested on a multiple-object tracking task and spatial working memory task under the four conditions: placebo, psilocybin (215 microg/kg), ketanserin (50 mg), and psilocybin and ketanserin. Psilocybin significantly reduced attentional tracking ability, but had no significant effect on spatial working memory, suggesting a functional dissociation between the two tasks. Pretreatment with ketanserin did not attenuate the effect of psilocybin on attentional performance, suggesting a primary involvement of the 5-HT1A receptor in the observed deficit. Based on physiological and pharmacological data, we speculate that this impaired attentional performance may reflect a reduced ability to suppress or ignore distracting stimuli rather than reduced attentional capacity. The clinical relevance of these results is also discussed.

Multi-Object Tracking with Correlation Filter for Autonomous Vehicle.

PubMed

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.

Big Data Provenance: Challenges, State of the Art and Opportunities.

PubMed

Wang, Jianwu; Crawl, Daniel; Purawat, Shweta; Nguyen, Mai; Altintas, Ilkay

2015-01-01

Ability to track provenance is a key feature of scientific workflows to support data lineage and reproducibility. The challenges that are introduced by the volume, variety and velocity of Big Data, also pose related challenges for provenance and quality of Big Data, defined as veracity. The increasing size and variety of distributed Big Data provenance information bring new technical challenges and opportunities throughout the provenance lifecycle including recording, querying, sharing and utilization. This paper discusses the challenges and opportunities of Big Data provenance related to the veracity of the datasets themselves and the provenance of the analytical processes that analyze these datasets. It also explains our current efforts towards tracking and utilizing Big Data provenance using workflows as a programming model to analyze Big Data.

Procedures for minimizing the effects of high solar activity on satellite tracking and ephemeris generation

NASA Technical Reports Server (NTRS)

Bredvik, Gordon D.

1990-01-01

We are currently experiencing a period of high solar radiation combined with wide short-term fluctuations in the radiation. The short-term fluctuations, especially when combined with highly energetic solar flares, can adversely affect the mission of U.S. Space Command's Space Surveillance Center (SSC) which catalogs and tracks the satellites in orbit around the Earth. Rapidly increasing levels of solar electromagnetic and/or particle radiation (solar wind) causes atmospheric warming, which, in turn, causes the upper-most portions of the atmosphere to expand outward, into the regime of low altitude satellites. The increased drag on satellites from this expansion can cause large, unmodeled, in-track displacements, thus undermining the SSC's ability to track and predict satellite position. On 13 March 1989, high solar radiation levels, combined with a high-energy solar flare, caused an exceptional amount of short-term atmospheric warming. The SSC temporarily lost track of over 1300 low altitude satellites--nearly half of the low altitude satellite population. Observational data on satellites that became lost during the days following the 13 March 'solar event' was analyzed and compared with the satellites' last element set prior to the event (referred to as a geomagnetic storm because of the large increase in magnetic flux in the upper atmosphere). The analysis led to a set of procedures for reducing the impact of future geomagnetic storms. These procedures adjust selected software limit parameters in the differential correction of element sets and in the observation association process and must be manually initiated at the onset of a geomagnetic storm. Sensor tasking procedures must be adjusted to ensure that a minimum of four observations per day are received for low altitude satellites. These procedures have been implemented and, thus far, appear to be successful in minimizing the effect of subsequent geomagnetic storms on satellite tracking and ephemeris computation.

Self-motion impairs multiple-object tracking.

PubMed

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.

Sensor Management for Fighter Applications

DTIC Science & Technology

2006-06-01

has consistently shown that by directly estimating the prob- ability density of a target state using a track - before - detect scheme, weak and densely... track - before - detect nonlinear filter was constructed to estimate the joint density of all state variables. A simulation that emulates estimator...targets in clutter and noise from sensed kinematic and identity data. Among the most capable is track - before - detect (TBD), which delivers

The application of measurement techniques to track flutter testing

NASA Technical Reports Server (NTRS)

Roglin, H. R.

1975-01-01

The application is discussed of measurement techniques to captive flight flutter tests at the Supersonic Naval Ordnance Research Track (SNORT), U. S. Naval Ordnance Test Station, China Lake, California. The high-speed track, by its ability to prove the validity of design and to accurately determine the actual margin of safety, offers a unique method of flutter testing for the aircraft design engineer.

Land-based lidar mapping: a new surveying technique to shed light on rapid topographic change

USGS Publications Warehouse

Collins, Brian D.; Kayen, Robert

2006-01-01

The rate of natural change in such dynamic environments as rivers and coastlines can sometimes overwhelm the monitoring capacity of conventional surveying methods. In response to this limitation, U.S. Geological Survey (USGS) scientists are pioneering new applications of light detection and ranging (lidar), a laser-based scanning technology that promises to greatly increase our ability to track rapid topographic changes and manage their impact on affected communities.

Cluster Analysis of Downscaled and Explicitly Simulated North Atlantic Tropical Cyclone Tracks

DOE PAGES

Daloz, Anne S.; Camargo, S. J.; Kossin, J. P.; ...

2015-02-11

A realistic representation of the North Atlantic tropical cyclone tracks is crucial as it allows, for example, explaining potential changes in U.S. landfalling systems. Here, the authors present a tentative study that examines the ability of recent climate models to represent North Atlantic tropical cyclone tracks. Tracks from two types of climate models are evaluated: explicit tracks are obtained from tropical cyclones simulated in regional or global climate models with moderate to high horizontal resolution (1°–0.25°), and downscaled tracks are obtained using a downscaling technique with large-scale environmental fields from a subset of these models. Here, for both configurations, tracksmore » are objectively separated into four groups using a cluster technique, leading to a zonal and a meridional separation of the tracks. The meridional separation largely captures the separation between deep tropical and subtropical, hybrid or baroclinic cyclones, while the zonal separation segregates Gulf of Mexico and Cape Verde storms. The properties of the tracks’ seasonality, intensity, and power dissipation index in each cluster are documented for both configurations. The authors’ results show that, except for the seasonality, the downscaled tracks better capture the observed characteristics of the clusters. The authors also use three different idealized scenarios to examine the possible future changes of tropical cyclone tracks under 1) warming sea surface temperature, 2) increasing carbon dioxide, and 3) a combination of the two. The response to each scenario is highly variable depending on the simulation considered. Lastly, the authors examine the role of each cluster in these future changes and find no preponderant contribution of any single cluster over the others.« less

Maintenance Decision Support System, Phase III

DOT National Transportation Integrated Search

2017-09-01

The main goal of the project was to address barriers that limit NDOTs ability to implement MDSS and MMS systems. The four project tasks included: Task 1: Develop system for tracking sand and/or deicing material usage: A system that tracks where and w...

"Kill the Baby": Making All Things Equal.

ERIC Educational Resources Information Center

Agne, Karen

1999-01-01

Suggests that the trend toward detracking and inclusion in schools is socio-politically motivated. Rebuts arguments that tracking is racist and damages self-esteem and identifies harmful effects of heterogeneous grouping. Concludes that tracking and ability grouping have a place in education. (SK)

Tracking multiple objects is limited only by object spacing, not by speed, time, or capacity.

PubMed

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.

Vehicle Tracking for an Evasive Manoeuvres Assistant Using Low-Cost Ultrasonic Sensors

PubMed Central

Jiménez, Felipe; Naranjo, José E.; Gómez, Oscar; Anaya, José J.

2014-01-01

Many driver assistance systems require knowledge of the vehicle environment. As these systems are increasing in complexity and performance, this knowledge of the environment needs to be more complete and reliable, so sensor fusion combining long, medium and short range sensors is now being used. This paper analyzes the feasibility of using ultrasonic sensors for low cost vehicle-positioning and tracking in the lane adjacent to the host vehicle in order to identify free areas around the vehicle and provide information to an automatic avoidance collision system that can perform autonomous braking and lane change manoeuvres. A laser scanner is used for the early detection of obstacles in the direction of travel while two ultrasonic sensors monitor the blind spot of the host vehicle. The results of tests on a test track demonstrate the ability of these sensors to accurately determine the kinematic variables of the obstacles encountered, despite a clear limitation in range. PMID:25460817

Developing and Integrating Advanced Movement Features Improves Automated Classification of Ciliate Species

PubMed Central

Soleymani, Ali; Pennekamp, Frank; Petchey, Owen L.; Weibel, Robert

2015-01-01

Recent advances in tracking technologies such as GPS or video tracking systems describe the movement paths of individuals in unprecedented details and are increasingly used in different fields, including ecology. However, extracting information from raw movement data requires advanced analysis techniques, for instance to infer behaviors expressed during a certain period of the recorded trajectory, or gender or species identity in case data is obtained from remote tracking. In this paper, we address how different movement features affect the ability to automatically classify the species identity, using a dataset of unicellular microbes (i.e., ciliates). Previously, morphological attributes and simple movement metrics, such as speed, were used for classifying ciliate species. Here, we demonstrate that adding advanced movement features, in particular such based on discrete wavelet transform, to morphological features can improve classification. These results may have practical applications in automated monitoring of waste water facilities as well as environmental monitoring of aquatic systems. PMID:26680591

The Use of Deconstructed Tires as Elastic Elements in Railway Tracks.

PubMed

Sol-Sánchez, Miguel; Moreno-Navarro, Fernando; Rubio-Gámez, Mª Carmen

2014-08-18

Elastic elements such as rail pads, under sleeper pads and under ballast mats are railway components that allow for a reduction in track deterioration and vibrations. And they are furthermore commonly used to obtain an optimal vertical stiffness of the infrastructure. However, the use of elastomeric materials can increase construction costs and the consumption of raw materials. Thus, the utilization of used tire layers offers an alternative to reuse an abundant waste reducing the cost of elastic elements. In addition, an innovator technique allows deconstructing tire layers without grinding up the material, reducing production costs at the same time that tire properties are remained. This research is focused on the study of the viability of developing elastic components from used tire layers by evaluating the influence of thickness, the resistance capacity of the elements and their behavior in a ballast box. Results indicate the ability of tire pads to manufacture elastic elements (rail pads, under sleeper pads and under ballast mats) to be used in railway tracks.

The Use of Deconstructed Tires as Elastic Elements in Railway Tracks

PubMed Central

Sol-Sánchez, Miguel; Moreno-Navarro, Fernando; Rubio-Gámez, Mª Carmen

2014-01-01

Elastic elements such as rail pads, under sleeper pads and under ballast mats are railway components that allow for a reduction in track deterioration and vibrations. And they are furthermore commonly used to obtain an optimal vertical stiffness of the infrastructure. However, the use of elastomeric materials can increase construction costs and the consumption of raw materials. Thus, the utilization of used tire layers offers an alternative to reuse an abundant waste reducing the cost of elastic elements. In addition, an innovator technique allows deconstructing tire layers without grinding up the material, reducing production costs at the same time that tire properties are remained. This research is focused on the study of the viability of developing elastic components from used tire layers by evaluating the influence of thickness, the resistance capacity of the elements and their behavior in a ballast box. Results indicate the ability of tire pads to manufacture elastic elements (rail pads, under sleeper pads and under ballast mats) to be used in railway tracks. PMID:28788168

Comparison of Two Kinds of Endurance Training Programs on the Effects of the Ability to Recover in Amateur Soccer Players

PubMed Central

Rogan, Slavko

2015-01-01

Background: High intensity intermittent aerobic exercise is an elementary endurance training exercise to build soccer endurance. Many studies exist with professional soccer players. But limited research has been conducted with amateur soccer players. Objectives: The aim of this study was to compare and assess the effects of the shuttle-run method and the Hoff-track method on the ability to recover in amateur soccer players within three weeks. Patients and Methods: Two amateur soccer teams were randomly assigned to shuttle-run group (n = 24; SRG) (SRG: shuttle-run group) or Hoff-track group (n = 18; HTG) (HTG: hoff-track group). They performed 2 times/week over three weeks their program. SRG performed a 20 m high speed shuttle-run until exhaustion and HTG covered at their highest speed level an obstacle track. Before and after training the yo-yo intermittent recovery test level 2 (YYIRTL2) was conducted. Results: Significant differences were observed within (P < 0.05) and between the groups (P = 0.06; ES = 0.50) in distance covering during YYIRTL2. Conclusions: Both training methods seem to improve the ability to recover in amateur soccer players within a short time period during the competition season. PMID:26448831

The LEAP™ Gesture Interface Device and Take-Home Laparoscopic Simulators: A Study of Construct and Concurrent Validity.

PubMed

Partridge, Roland W; Brown, Fraser S; Brennan, Paul M; Hennessey, Iain A M; Hughes, Mark A

2016-02-01

To assess the potential of the LEAP™ infrared motion tracking device to map laparoscopic instrument movement in a simulated environment. Simulator training is optimized when augmented by objective performance feedback. We explore the potential LEAP has to provide this in a way compatible with affordable take-home simulators. LEAP and the previously validated InsTrac visual tracking tool mapped expert and novice performances of a standardized simulated laparoscopic task. Ability to distinguish between the 2 groups (construct validity) and correlation between techniques (concurrent validity) were the primary outcome measures. Forty-three expert and 38 novice performances demonstrated significant differences in LEAP-derived metrics for instrument path distance (P < .001), speed (P = .002), acceleration (P < .001), motion smoothness (P < .001), and distance between the instruments (P = .019). Only instrument path distance demonstrated a correlation between LEAP and InsTrac tracking methods (novices: r = .663, P < .001; experts: r = .536, P < .001). Consistency of LEAP tracking was poor (average % time hands not tracked: 31.9%). The LEAP motion device is able to track the movement of hands using instruments in a laparoscopic box simulator. Construct validity is demonstrated by its ability to distinguish novice from expert performances. Only time and instrument path distance demonstrated concurrent validity with an existing tracking method however. A number of limitations to the tracking method used by LEAP have been identified. These need to be addressed before it can be considered an alternative to visual tracking for the delivery of objective performance metrics in take-home laparoscopic simulators. © The Author(s) 2015.

Orbiting Deep Space Relay Station (ODSRS). Volume 1: Requirement determination

NASA Technical Reports Server (NTRS)

Hunter, J. A.

1979-01-01

The deep space communications requirements of the post-1985 time frame are described and the orbiting deep space relay station (ODSRS) is presented as an option for meeting these requirements. Under current conditions, the ODSRS is not yet cost competitive with Earth based stations to increase DSN telemetry performance, but has significant advantages over a ground station, and these are sufficient to maintain it as a future option. These advantages include: the ability to track a spacecraft 24 hours per day with ground stations located only in the USA; the ability to operate at higher frequencies that would be attenuated by Earth's atmosphere; and the potential for building very large structures without the constraints of Earth's gravity.

Alcohol and disorientation-related responses. IV, Effects of different alcohol dosages and display illumination tracking performance during vestibular stimulation.

DOT National Transportation Integrated Search

1971-07-01

A previous CAMI laboratory investigation showed that alcohol impairs the ability of men to suppress vestibular nystagmus while visually fixating on a cockpit instrument, thus degrading visual tracking performance (eye-hand coordination) during angula...

Gentrification, Schooling and Social Inequality

ERIC Educational Resources Information Center

DeSena, Judith N.; Ansalone, George

2009-01-01

Tracking or the separation of students by ability and curriculum is pervasive in American schooling despite the fact that contemporary research has associated this educational structure with negative student outcomes. Opponents of tracking contend that it deprives underprivileged children of excellence and equity in education and separates them…

Development of a Remotely Operated Autonomous Satellite Tracking System

DTIC Science & Technology

2010-03-01

ability of Commercial-Off-The-Shelf (COTS) optical observation equipment to track and image Low Earth Orbiting (LEO) satellites. Using radar data in...SOR operates one of the world’s premier adaptive-optics telescopes capable of tracking low -earth orbiting satellites. The telescope has a 3.5-meter...student) published his thesis Initial Determination of Low Earth Orbits Using Commercial Telescopes. According to this document’s Problem Statement

Volumetric analysis of cerebellum in short-track speed skating players.

PubMed

Park, In Sung; Lee, Nam Joon; Kim, Tae-Young; Park, Jin-Hoon; Won, Yu-Mi; Jung, Yong-Ju; Yoon, Jin-Hwan; Rhyu, Im Joo

2012-12-01

The cerebellum is associated with balance control and coordination, which might be important for gliding on smooth ice at high speeds. A number of case studies have shown that cerebellar damage induces impaired balance and coordination. As a positive model, therefore, we investigated whether plastic changes in the volumes of cerebellar subregions occur in short-track speed skating players who must have extraordinary abilities of balance and coordination, using three-dimensional magnetic resonance imaging volumetry. The manual tracing was performed and the volumes of cerebellar hemisphere and vermian lobules were compared between short-track speed skating players (n=16) and matched healthy controls (n=18). We found larger right cerebellar hemisphere volume and vermian lobules VI-VII (declive, folium, and tuber) in short-track speed skating players in comparison with the matched controls. The finding suggests that the specialized abilities of balance and coordination are associated with structural plasticity of the right hemisphere of cerebellum and vermian VI-VII and these regions play an essential role in balance and coordination.

SLATE: scanning laser automatic threat extraction

NASA Astrophysics Data System (ADS)

Clark, David J.; Prickett, Shaun L.; Napier, Ashley A.; Mellor, Matthew P.

2016-10-01

SLATE is an Autonomous Sensor Module (ASM) designed to work with the SAPIENT system providing accurate location tracking and classifications of targets that pass through its field of view. The concept behind the SLATE ASM is to produce a sensor module that provides a complementary view of the world to the camera-based systems that are usually used for wide area surveillance. Cameras provide a hi-fidelity, human understandable view of the world with which tracking and identification algorithms can be used. Unfortunately, positioning and tracking in a 3D environment is difficult to implement robustly, making location-based threat assessment challenging. SLATE uses a Scanning Laser Rangefinder (SLR) that provides precise (<1cm) positions, sizes, shapes and velocities of targets within its field-of-view (FoV). In this paper we will discuss the development of the SLATE ASM including the techniques used to track and classify detections that move through the field of view of the sensor providing the accurate tracking information to the SAPIENT system. SLATE's ability to locate targets precisely allows subtle boundary-crossing judgements, e.g. on which side of a chain-link fence a target is. SLATE's ability to track targets in 3D throughout its FoV enables behavior classification such as running and walking which can provide an indication of intent and help reduce false alarm rates.

In vivo MRI cell tracking using perfluorocarbon probes and fluorine-19 detection

PubMed Central

Ahrens, Eric T.; Zhong, Jia

2013-01-01

This article is a brief survey of preclinical in vivo cell tracking methods and applications using perfluorocarbon (PFC) probes and fluorine-19 (19F) MRI detection. Detection of the 19F signal offers high cell specificity and quantification abilities in spin-density weighted MR images. We discuss the compositions of matter, methods, and applications of PFC-based cell tracking using ex vivo and in situ PFC labeling in preclinical studies of inflammation and cellular therapeutics. We will also address potential applicability of 19F cell tracking to clinical trials. PMID:23606473

Neural substrates of dynamic object occlusion.

PubMed

Shuwairi, Sarah M; Curtis, Clayton E; Johnson, Scott P

2007-08-01

In everyday environments, objects frequently go out of sight as they move and our view of them becomes obstructed by nearer objects, yet we perceive these objects as continuous and enduring entities. Here, we used functional magnetic resonance imaging with an attentive tracking paradigm to clarify the nature of perceptual and cognitive mechanisms subserving this ability to fill in the gaps in perception of dynamic object occlusion. Imaging data revealed distinct regions of cortex showing increased activity during periods of occlusion relative to full visibility. These regions may support active maintenance of a representation of the target's spatiotemporal properties ensuring that the object is perceived as a persisting entity when occluded. Our findings may shed light on the neural substrates involved in object tracking that give rise to the phenomenon of object permanence.

Big Data Provenance: Challenges, State of the Art and Opportunities

PubMed Central

Wang, Jianwu; Crawl, Daniel; Purawat, Shweta; Nguyen, Mai; Altintas, Ilkay

2017-01-01

Ability to track provenance is a key feature of scientific workflows to support data lineage and reproducibility. The challenges that are introduced by the volume, variety and velocity of Big Data, also pose related challenges for provenance and quality of Big Data, defined as veracity. The increasing size and variety of distributed Big Data provenance information bring new technical challenges and opportunities throughout the provenance lifecycle including recording, querying, sharing and utilization. This paper discusses the challenges and opportunities of Big Data provenance related to the veracity of the datasets themselves and the provenance of the analytical processes that analyze these datasets. It also explains our current efforts towards tracking and utilizing Big Data provenance using workflows as a programming model to analyze Big Data. PMID:29399671

Numerosity and number signs in deaf Nicaraguan adults

PubMed Central

Flaherty, Molly; Senghas, Ann

2012-01-01

What abilities are entailed in being numerate? Certainly, one is the ability to hold the exact quantity of a set in mind, even as it changes, and even after its members can no longer be perceived. Is counting language necessary to track and reproduce exact quantities? Previous work with speakers of languages that lack number words involved participants only from non-numerate cultures. Deaf Nicaraguan adults all live in a richly numerate culture, but vary in counting ability, allowing us to experimentally differentiate the contribution of these two factors. Thirty deaf and 10 hearing participants performed 11 one-to-one matching and counting tasks. Results suggest that immersion in a numerate culture is not enough to make one fully numerate. A memorized sequence of number symbols is required, though even an unconventional, iconic system is sufficient. Additionally, we find that within a numerate culture, the ability to track precise quantities can be acquired in adulthood. PMID:21899832

Tracking, Inequality, and the Rhetoric of Reform: Why Schools Don't Change.

ERIC Educational Resources Information Center

Oakes, Jeannie

1986-01-01

Examines the historical, political, and economic context of differentiated schooling. Argues that tracking perpetuates inequality. Evaluates the influence on education of the politics of economic scarcity, social conservatism, and assumptions about abilities and the role of schools in providing equal opportunity. (KH)

The what-where trade-off in multiple-identity tracking.

PubMed

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.

Target-type probability combining algorithms for multisensor tracking

NASA Astrophysics Data System (ADS)

Wigren, Torbjorn

2001-08-01

Algorithms for the handing of target type information in an operational multi-sensor tracking system are presented. The paper discusses recursive target type estimation, computation of crosses from passive data (strobe track triangulation), as well as the computation of the quality of the crosses for deghosting purposes. The focus is on Bayesian algorithms that operate in the discrete target type probability space, and on the approximations introduced for computational complexity reduction. The centralized algorithms are able to fuse discrete data from a variety of sensors and information sources, including IFF equipment, ESM's, IRST's as well as flight envelopes estimated from track data. All algorithms are asynchronous and can be tuned to handle clutter, erroneous associations as well as missed and erroneous detections. A key to obtain this ability is the inclusion of data forgetting by a procedure for propagation of target type probability states between measurement time instances. Other important properties of the algorithms are their abilities to handle ambiguous data and scenarios. The above aspects are illustrated in a simulations study. The simulation setup includes 46 air targets of 6 different types that are tracked by 5 airborne sensor platforms using ESM's and IRST's as data sources.

A lentiviral vector with a short troponin-I promoter for tracking cardiomyocyte differentiation of human embryonic stem cells.

PubMed

Gallo, P; Grimaldi, S; Latronico, M V G; Bonci, D; Pagliuca, A; Gallo, P; Ausoni, S; Peschle, C; Condorelli, G

2008-02-01

Human embryonic stem cells (hESCs) may become important for cardiac repair due to their potentially unlimited ability to generate cardiomyocytes (CMCs). Moreover, genetic manipulation of hESC-derived CMCs would be a very promising technique for curing myocardial disorders. At the present time, however, inducing the differentiation of hESCs into CMCs is extremely difficult and, therefore, an easy and standardizable technique is needed to evaluate differentiation strategies. Vectors driving cardiac-specific expression may represent an important tool not only for monitoring new cardiac-differentiation strategies, but also for the manipulation of cardiac differentiation of ESCs. To this aim, we generated cardiac-specific lentiviral vectors (LVVs) in which expression is driven by a short fragment of the cardiac troponin-I proximal promoter (TNNI3) with a human cardiac alpha-actin enhancer, and tested its suitability in inducing tissue-specific gene expression and ability to track the CMC lineage during differentiation of ESCs. We determined that (1) TNNI3-LVVs efficiently drive cardiac-specific gene expression and mark the cardiomyogenic lineage in human and mouse ESC differentiation systems (2) the cardiac alpha-actin enhancer confers a further increase in gene-expression specificity of TNNI3-LVVs in hESCs. Although this technique may not be useful in tracking small numbers of cells, data suggested that TNNI3-based LVVs are a powerful tool for manipulating human ESCs and modifying hESC-derived CMCs.

Real-time auto-adaptive margin generation for MLC-tracked radiotherapy

NASA Astrophysics Data System (ADS)

Glitzner, M.; Fast, M. F.; de Senneville, B. Denis; Nill, S.; Oelfke, U.; Lagendijk, J. J. W.; Raaymakers, B. W.; Crijns, S. P. M.

2017-01-01

In radiotherapy, abdominal and thoracic sites are candidates for performing motion tracking. With real-time control it is possible to adjust the multileaf collimator (MLC) position to the target position. However, positions are not perfectly matched and position errors arise from system delays and complicated response of the electromechanic MLC system. Although, it is possible to compensate parts of these errors by using predictors, residual errors remain and need to be compensated to retain target coverage. This work presents a method to statistically describe tracking errors and to automatically derive a patient-specific, per-segment margin to compensate the arising underdosage on-line, i.e. during plan delivery. The statistics of the geometric error between intended and actual machine position are derived using kernel density estimators. Subsequently a margin is calculated on-line according to a selected coverage parameter, which determines the amount of accepted underdosage. The margin is then applied onto the actual segment to accommodate the positioning errors in the enlarged segment. The proof-of-concept was tested in an on-line tracking experiment and showed the ability to recover underdosages for two test cases, increasing {{V}90 %} in the underdosed area about 47 % and 41 % , respectively. The used dose model was able to predict the loss of dose due to tracking errors and could be used to infer the necessary margins. The implementation had a running time of 23 ms which is compatible with real-time requirements of MLC tracking systems. The auto-adaptivity to machine and patient characteristics makes the technique a generic yet intuitive candidate to avoid underdosages due to MLC tracking errors.

Can smartwatches replace smartphones for posture tracking?

PubMed

Mortazavi, Bobak; Nemati, Ebrahim; VanderWall, Kristina; Flores-Rodriguez, Hector G; Cai, Jun Yu Jacinta; Lucier, Jessica; Naeim, Arash; Sarrafzadeh, Majid

2015-10-22

This paper introduces a human posture tracking platform to identify the human postures of sitting, standing or lying down, based on a smartwatch. This work develops such a system as a proof-of-concept study to investigate a smartwatch's ability to be used in future remote health monitoring systems and applications. This work validates the smartwatches' ability to track the posture of users accurately in a laboratory setting while reducing the sampling rate to potentially improve battery life, the first steps in verifying that such a system would work in future clinical settings. The algorithm developed classifies the transitions between three posture states of sitting, standing and lying down, by identifying these transition movements, as well as other movements that might be mistaken for these transitions. The system is trained and developed on a Samsung Galaxy Gear smartwatch, and the algorithm was validated through a leave-one-subject-out cross-validation of 20 subjects. The system can identify the appropriate transitions at only 10 Hz with an F-score of 0.930, indicating its ability to effectively replace smart phones, if needed.

Mentoring Nontenured Track Nursing Faculty: A Systematic Review.

PubMed

Cullen, Deborah; Shieh, Carol; McLennon, Susan M; Pike, Caitlin; Hartman, Taylor; Shah, Hena

The purpose of this systematic review was to evaluate the effectiveness of mentoring strategies for nursing faculty progression and productivity in the nontenure track at institutions of higher education. Sixty articles were included in the review. Findings revealed that nontenure track nursing faculty require planned programs and mentoring strategies unique to their role and abilities. Schools of nursing can improve on faculty progression, scholarship, and career growth by providing structured mentoring activity.

On the internal target model in a tracking task

NASA Technical Reports Server (NTRS)

Caglayan, A. K.; Baron, S.

1981-01-01

An optimal control model for predicting operator's dynamic responses and errors in target tracking ability is summarized. The model, which predicts asymmetry in the tracking data, is dependent on target maneuvers and trajectories. Gunners perception, decision making, control, and estimate of target positions and velocity related to crossover intervals are discussed. The model provides estimates for means, standard deviations, and variances for variables investigated and for operator estimates of future target positions and velocities.

C-arm rotation encoding with accelerometers.

PubMed

Grzeda, Victor; Fichtinger, Gabor

2010-07-01

Fluoroscopic C-arms are being incorporated in computer-assisted interventions in increasing number. For these applications to work, the relative poses of imaging must be known. To find the pose, tracking methods such as optical cameras, electromagnetic trackers, and radiographic fiducials have been used-all hampered by significant shortcomings. We propose to recover the rotational pose of the C-arm using the angle-sensing ability of accelerometers, by exploiting the capability of the accelerometer to measure tilt angles. By affixing the accelerometer to a C-arm, the accelerometer tracks the C-arm pose during rotations of the C-arm. To demonstrate this concept, a C-arm analogue was constructed with a webcam device affixed to the C-arm model to mimic X-ray imaging. Then, measuring the offset between the accelerometer angle readings to the webcam pose angle, an angle correction equation (ACE) was created to properly tracking the C-arm rotational pose. Several tests were performed on the webcam C-arm model using the ACEs to tracking the primary and secondary angle rotations of the model. We evaluated the capability of linear and polynomial ACEs to tracking the webcam C-arm pose angle for different rotational scenarios. The test results showed that the accelerometer could track the pose of the webcam C-arm model with an accuracy of less than 1.0 degree. The accelerometer was successful in sensing the C-arm's rotation with clinically adequate accuracy in the C-arm webcam model.

Changes in sleep habits between 1985 and 2013 among children and adolescents in Sweden.

PubMed

Norell-Clarke, Annika; Hagquist, Curt

2017-12-01

The aim was to investigate changes in child and adolescent sleep habits in Sweden over time. This had not been done previously. Cross-sectional questionnaire data over three decades of investigations of the Health Behaviours of School Children study (1985/1986, 2005/2006 and 2013/2014) were used. The sample included 18,682 children and adolescents, aged 11, 13 and 15. Empirically based age-specific sleep duration recommendations were used to operationalise sleep duration. The results showed that, over time, fewer go to bed early and more go to bed late. Regarding sleep duration, there have been decreases in the proportion of children and adolescents that sleep as much as is recommended for their age. Sleep onset difficulties have increased for all ages and increase the odds of sleeping less than recommended as well as having late bedtimes. Boys were more likely than girls to have later bedtimes and to sleep less than recommended. A vocational educational track, not planning to study further or being unsure of which track to choose increased the odds for 15 year olds to have late bedtimes and to sleep less than recommended compared with a college preparatory track. The results indicate that over time, fewer children and adolescents attain sufficient sleep duration. This may have implications for study results, mental health and cognitive abilities.

Program Tracks Cost Of Travel

NASA Technical Reports Server (NTRS)

Mauldin, Lemuel E., III

1993-01-01

Travel Forecaster is menu-driven, easy-to-use computer program that plans, forecasts cost, and tracks actual vs. planned cost of business-related travel of division or branch of organization and compiles information into data base to aid travel planner. Ability of program to handle multiple trip entries makes it valuable time-saving device.

Teachers' Attitudes towards Tracking: Testing the Socialization Hypothesis

ERIC Educational Resources Information Center

Mouralová, Magdalena; Paulus, Michal; Veselý, Arnošt

2017-01-01

The paper examines how teachers' attitudes towards tracking (separating pupils into groups with different curricula on the basis of their abilities and results) differ among various generations of teachers. Fundamental and quick changes in the educational system occurred in the Czech Republic after the Velvet Revolution in 1989 as a unified…

Developing a Faculty Learning Community for Non-Tenure Track Professors

ERIC Educational Resources Information Center

Bond, Nathan

2015-01-01

Non-tenure track faculty vary greatly in terms of their ranks, teaching abilities, workloads, and motivational levels and have unique professional development needs. In response, universities are differentiating professional development for these professors. This case study examined an emerging research university's efforts to provide a faculty…

Light scattering apparatus and method for determining radiation exposure to plastic detectors

DOEpatents

Hermes, Robert E.

2002-01-01

An improved system and method of analyzing cumulative radiation exposure registered as pits on track etch foils of radiation dosimeters. The light scattering apparatus and method of the present invention increases the speed of analysis while it also provides the ability to analyze exposure levels beyond that which may be properly measured with conventional techniques. Dosimeters often contain small plastic sheets that register accumulated damage when exposed to a radiation source. When the plastic sheet from the dosimeter is chemically etched, a track etch foil is produced wherein pits or holes are created in the plastic. The number of these pits, or holes, per unit of area (pit density) correspond to the amount of cumulative radiation exposure which is being optically measured by the apparatus. To measure the cumulative radiation exposure of a track etch foil a high intensity collimated beam is passed through foil such that the pits and holes within the track etch foil cause a portion of the impinging light beam to become scattered upon exit. The scattered light is focused with a lens, while the primary collimated light beam (unscattered light) is blocked. The scattered light is focused by the lens onto an optical detector capable of registering the optical power of the scattered light which corresponds to the cumulative radiation to which the track etch foil has been exposed.

Cell migration through connective tissue in 3-D

NASA Astrophysics Data System (ADS)

Fabry, Ben

2008-03-01

A prerequisite for metastasis formation is the ability of tumor cells to invade and migrate through connective tissue. Four key components endow tumor cells with this ability: secretion of matrix-degrading enzymes, firm but temporary adhesion onto connective tissue fibers, contractile force generation, and rapid remodeling of cytoskeletal structures. Cell adhesion, contraction, and cytoskeletal remodeling are biomechanical parameter that can be measured on single cells using a panel of biophysical methods. We use 2-D and 3-D traction microscopy to measure contractile forces; magnetic tweezer microrheology to estimate adhesion strengths, cytoskeletal stiffness and molecular turn-over rates; and nanoscale particle tracking to measure cytoskeletal remodeling. On a wide range of tumor cell lines we could show that cell invasiveness correlates with increased expression of integrin adhesion receptors, increased contractile force generation, and increased speed of cytoskeletal reorganization. Each of those biomechanical parameters, however, varied considerably between cell lines of similar invasivity, suggesting that tumor cells employ multiple invasion strategies that cannot be unambiguously characterized using a single assay.

[Developmental change in facial recognition by premature infants during infancy].

PubMed

Konishi, Yukihiko; Kusaka, Takashi; Nishida, Tomoko; Isobe, Kenichi; Itoh, Susumu

2014-09-01

Premature infants are thought to be at increased risk for developmental disorders. We evaluated facial recognition by premature infants during early infancy, as this ability has been reported to be impaired commonly in developmentally disabled children. In premature infants and full-term infants at the age of 4 months (4 corrected months for premature infants), visual behaviors while performing facial recognition tasks were determined and analyzed using an eye-tracking system (Tobii T60 manufactured by Tobii Technologics, Sweden). Both types of infants had a preference towards normal facial expressions; however, no preference towards the upper face was observed in premature infants. Our study suggests that facial recognition ability in premature infants may develop differently from that in full-term infants.

Characterization of Factors Affecting Nanoparticle Tracking Analysis Results With Synthetic and Protein Nanoparticles.

PubMed

Krueger, Aaron B; Carnell, Pauline; Carpenter, John F

2016-04-01

In many manufacturing and research areas, the ability to accurately monitor and characterize nanoparticles is becoming increasingly important. Nanoparticle tracking analysis is rapidly becoming a standard method for this characterization, yet several key factors in data acquisition and analysis may affect results. Nanoparticle tracking analysis is prone to user input and bias on account of a high number of parameters available, contains a limited analysis volume, and individual sample characteristics such as polydispersity or complex protein solutions may affect analysis results. This study systematically addressed these key issues. The integrated syringe pump was used to increase the sample volume analyzed. It was observed that measurements recorded under flow caused a reduction in total particle counts for both polystyrene and protein particles compared to those collected under static conditions. In addition, data for polydisperse samples tended to lose peak resolution at higher flow rates, masking distinct particle populations. Furthermore, in a bimodal particle population, a bias was seen toward the larger species within the sample. The impacts of filtration on an agitated intravenous immunoglobulin sample and operating parameters including "MINexps" and "blur" were investigated to optimize the method. Taken together, this study provides recommendations on instrument settings and sample preparations to properly characterize complex samples. Copyright © 2016. Published by Elsevier Inc.

A multispectral automatic target recognition application for maritime surveillance, search, and rescue

NASA Astrophysics Data System (ADS)

Schoonmaker, Jon; Reed, Scott; Podobna, Yuliya; Vazquez, Jose; Boucher, Cynthia

2010-04-01

Due to increased security concerns, the commitment to monitor and maintain security in the maritime environment is increasingly a priority. A country's coast is the most vulnerable area for the incursion of illegal immigrants, terrorists and contraband. This work illustrates the ability of a low-cost, light-weight, multi-spectral, multi-channel imaging system to handle the environment and see under difficult marine conditions. The system and its implemented detecting and tracking technologies should be organic to the maritime homeland security community for search and rescue, fisheries, defense, and law enforcement. It is tailored for airborne and ship based platforms to detect, track and monitor suspected objects (such as semi-submerged targets like marine mammals, vessels in distress, and drug smugglers). In this system, automated detection and tracking technology is used to detect, classify and localize potential threats or objects of interest within the imagery provided by the multi-spectral system. These algorithms process the sensor data in real time, thereby providing immediate feedback when features of interest have been detected. A supervised detection system based on Haar features and Cascade Classifiers is presented and results are provided on real data. The system is shown to be extendable and reusable for a variety of different applications.

Anomalous Dynamical Behavior of Freestanding Graphene Membranes

NASA Astrophysics Data System (ADS)

Ackerman, M. L.; Kumar, P.; Neek-Amal, M.; Thibado, P. M.; Peeters, F. M.; Singh, Surendra

2016-09-01

We report subnanometer, high-bandwidth measurements of the out-of-plane (vertical) motion of atoms in freestanding graphene using scanning tunneling microscopy. By tracking the vertical position over a long time period, a 1000-fold increase in the ability to measure space-time dynamics of atomically thin membranes is achieved over the current state-of-the-art imaging technologies. We observe that the vertical motion of a graphene membrane exhibits rare long-scale excursions characterized by both anomalous mean-squared displacements and Cauchy-Lorentz power law jump distributions.

Marketing quality and value to the managed care market.

PubMed

Kazmirski, G

1998-11-01

Quantifying quality and marketing care delivery have been long-term challenges in the health care market. Insurers, employers, other purchasers of care, and providers face a constant challenge in positioning their organizations in a proactive, competitive niche. Tools that measure patient's self-reported perception of health care needs and expectations have increased the ability to quantify quality of care delivery. When integrated with case management and disease management strategies, outcomes reporting and variance analysis tracking can be packaged to position a provider in a competitive niche.

Protection by Inhaled Hydrogen Therapy in a Rat Model of Acute Lung Injury can be Tracked in vivo Using Molecular Imaging.

PubMed

Audi, Said H; Jacobs, Elizabeth R; Zhang, Xiao; Camara, Amadou K S; Zhao, Ming; Medhora, Meetha M; Rizzo, Benjamin; Clough, Anne V

2017-10-01

Inhaled hydrogen gas (H2) provides protection in rat models of human acute lung injury (ALI). We previously reported that biomarker imaging can detect oxidative stress and endothelial cell death in vivo in a rat model of ALI. Our objective was to evaluate the ability of Tc-hexamethylpropyleneamineoxime (HMPAO) and Tc-duramycin to track the effectiveness of H2 therapy in vivo in the hyperoxia rat model of ALI. Rats were exposed to room air (normoxia), 98% O2 + 2% N2 (hyperoxia) or 98% O2 + 2% H2 (hyperoxia+H2) for up to 60 h. In vivo scintigraphy images were acquired following injection of Tc-HMPAO or Tc-duramycin. For hyperoxia rats, Tc-HMPAO and Tc-duramycin lung uptake increased in a time-dependent manner, reaching a maximum increase of 270% and 150% at 60 h, respectively. These increases were reduced to 120% and 70%, respectively, in hyperoxia+H2 rats. Hyperoxia exposure increased glutathione content in lung homogenate (36%) more than hyperoxia+H2 (21%), consistent with increases measured in Tc-HMPAO lung uptake. In 60-h hyperoxia rats, pleural effusion, which was undetectable in normoxia rats, averaged 9.3 gram/rat, and lung tissue 3-nitrotyrosine expression increased by 790%. Increases were reduced by 69% and 59%, respectively, in 60-h hyperoxia+H2 rats. This study detects and tracks the anti-oxidant and anti-apoptotic properties of H2 therapy in vivo after as early as 24 h of hyperoxia exposure. The results suggest the potential utility of these SPECT biomarkers for in vivo assessment of key cellular pathways in the pathogenesis of ALI and for monitoring responses to therapies.

Driving with a short arm cast in a simulator.

PubMed

Mansour, Damian; Mansour, Kristin Gotaas; Kenny, Benjamin William; Attia, John; Meads, Bryce

2015-12-01

To test the ability to steer in a driving simulator in subjects with a short arm cast. 17 men and 13 women aged 23 to 67 (mean, 37) years who had a valid driver's licence were randomised to the cast-first group (n=16; 7 had the cast on the dominant arm) or the cast-second group (n=14; 8 had the cast on the dominant arm) and drove in a simulator. A short arm plaster-of-Paris cast was applied in a neutral position, allowing free movement of the metacarpophalangeal joints, thumb, and elbow joint. Outcome measures included the number of driving off track instances, the number of crashes, the lap time, and the effect of hand dominance on these parameters. Subjects were asked whether the cast had impeded their steering ability. Subjects with or without a cast were comparable in terms of the number of driving off track instances, number of crashes, and lap time. Compared with no cast, the odds ratio (OR) of a subject in a cast driving off the track was 1.02 (p=0.921) and having a crash was 0.79 (p=0.047). All subjects were 1.23 times more likely to drive off the track in their first lap (OR=2.66, p=0.019). The mean lap time decreased for each consecutive lap from the 2nd to 5th laps. Subjects driving with a cast on the dominant or non-dominant arm were comparable. 26 out of the 30 participants considered that the plaster cast impeded their steering ability. Compared with no cast, driving with a short arm cast did not significantly decrease steering ability in a driving simulator.

TRACKING Trounces Test Scores

ERIC Educational Resources Information Center

Education Digest: Essential Readings Condensed for Quick Review, 2004

2004-01-01

This article presents an adaptation of an article from School Board News, January 6, 2004 edition. The article describes the effort of de-tracking students of varying ability levels, made by officials of South Side High School, in Rockville Centre, New York, and Noble High School, in North Berwick, Maine. Officials from both schools say that the…

Observing with SOAR | SOAR

Science.gov Websites

Control Room SOAR offers both classical (on-site) observing (SOAR Control Room, right), and remote tools you need for preparing your science proposal and then carrying out your program. Tracking at Non -Sidereal Rates with SOAR The SOAR telescope has the ability to track at non-sidereal rates, ideal for

Tracking of "Moving" Fused Auditory Images by Children.

ERIC Educational Resources Information Center

Cranford, Jerry L.; And Others

1993-01-01

This study evaluated the ability of 30 normally developing children (ages 6-12) to report the perceived location of a stationary fused auditory image (FAI) or track a "moving" FAI. Although subjects performed at normal adult levels with the stationary sound measure, they exhibited a significant age-related trend with the moving sound…

Empathy, Self-Reflection, and Curriculum Choice

ERIC Educational Resources Information Center

Grosseman, Suely; Hojat, Mohammadreza; Duke, Pamela M.; Mennin, Stewart; Rosenzweig, Steven; Novack, Dennis

2014-01-01

We administered the Jefferson Scale of Empathy and the Groningen Reflection Ability Scale to 61 of 64 entering medical students who self-selected a problem-based learning curricular track and to 163 of 198 who self-selected a lecture-based track (response rates of 95.3% and 82.3%, respectively, with no statistically significant differences in mean…

Wireless tracking of cotton modules. Part I: Automatic message triggering

USDA-ARS?s Scientific Manuscript database

The ability to map profit across a cotton field would enable producers to see where money is being made or lost on their farms and to implement precise field management practices to ensure the highest return possible on each portion of a field. To this end, a wireless module-tracking system was rec...

76 FR 1182 - Determination of System Attributes for the Tracking and Tracing of Prescription Drugs; Public...

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...

The Influence of Ability Grouping on Math Achievement in a Rural Middle School

ERIC Educational Resources Information Center

Pritchard, Robert R.

2012-01-01

The researcher examined the academic performance of low-tracked students (n = 156) using standardized math test scores to determine whether there is a statistically significant difference in achievement depending on academic environment, tracked or nontracked. An analysis of variance (ANOVA) was calculated, using a paired samples t-test for a…

78 FR 13006 - New Intelligent Mail Package Barcode Standards To Enhance Package Visibility; Opportunity for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-26

...The Postal Service is exploring the advisability of requiring the use of Intelligent Mail[supreg] package barcodes (IMpb) or unique tracking Intelligent Mail barcodes (IMbTM) on all commercial parcels, and providing support to mailers to assure their ability to apply unique tracking barcodes to all commercial parcels.

The Type-2 Fuzzy Logic Controller-Based Maximum Power Point Tracking Algorithm and the Quadratic Boost Converter for Pv System

NASA Astrophysics Data System (ADS)

Altin, Necmi

2018-05-01

An interval type-2 fuzzy logic controller-based maximum power point tracking algorithm and direct current-direct current (DC-DC) converter topology are proposed for photovoltaic (PV) systems. The proposed maximum power point tracking algorithm is designed based on an interval type-2 fuzzy logic controller that has an ability to handle uncertainties. The change in PV power and the change in PV voltage are determined as inputs of the proposed controller, while the change in duty cycle is determined as the output of the controller. Seven interval type-2 fuzzy sets are determined and used as membership functions for input and output variables. The quadratic boost converter provides high voltage step-up ability without any reduction in performance and stability of the system. The performance of the proposed system is validated through MATLAB/Simulink simulations. It is seen that the proposed system provides high maximum power point tracking speed and accuracy even for fast changing atmospheric conditions and high voltage step-up requirements.

Object tracking algorithm based on the color histogram probability distribution

NASA Astrophysics Data System (ADS)

Li, Ning; Lu, Tongwei; Zhang, Yanduo

2018-04-01

In order to resolve tracking failure resulted from target's being occlusion and follower jamming caused by objects similar to target in the background, reduce the influence of light intensity. This paper change HSV and YCbCr color channel correction the update center of the target, continuously updated image threshold self-adaptive target detection effect, Clustering the initial obstacles is roughly range, shorten the threshold range, maximum to detect the target. In order to improve the accuracy of detector, this paper increased the Kalman filter to estimate the target state area. The direction predictor based on the Markov model is added to realize the target state estimation under the condition of background color interference and enhance the ability of the detector to identify similar objects. The experimental results show that the improved algorithm more accurate and faster speed of processing.

3D Visual Tracking of an Articulated Robot in Precision Automated Tasks

PubMed Central

Alzarok, Hamza; Fletcher, Simon; Longstaff, Andrew P.

2017-01-01

The most compelling requirements for visual tracking systems are a high detection accuracy and an adequate processing speed. However, the combination between the two requirements in real world applications is very challenging due to the fact that more accurate tracking tasks often require longer processing times, while quicker responses for the tracking system are more prone to errors, therefore a trade-off between accuracy and speed, and vice versa is required. This paper aims to achieve the two requirements together by implementing an accurate and time efficient tracking system. In this paper, an eye-to-hand visual system that has the ability to automatically track a moving target is introduced. An enhanced Circular Hough Transform (CHT) is employed for estimating the trajectory of a spherical target in three dimensions, the colour feature of the target was carefully selected by using a new colour selection process, the process relies on the use of a colour segmentation method (Delta E) with the CHT algorithm for finding the proper colour of the tracked target, the target was attached to the six degree of freedom (DOF) robot end-effector that performs a pick-and-place task. A cooperation of two Eye-to Hand cameras with their image Averaging filters are used for obtaining clear and steady images. This paper also examines a new technique for generating and controlling the observation search window in order to increase the computational speed of the tracking system, the techniques is named Controllable Region of interest based on Circular Hough Transform (CRCHT). Moreover, a new mathematical formula is introduced for updating the depth information of the vision system during the object tracking process. For more reliable and accurate tracking, a simplex optimization technique was employed for the calculation of the parameters for camera to robotic transformation matrix. The results obtained show the applicability of the proposed approach to track the moving robot with an overall tracking error of 0.25 mm. Also, the effectiveness of CRCHT technique in saving up to 60% of the overall time required for image processing. PMID:28067860

Airborne target tracking algorithm against oppressive decoys in infrared imagery

NASA Astrophysics Data System (ADS)

Sun, Xiechang; Zhang, Tianxu

2009-10-01

This paper presents an approach for tracking airborne target against oppressive infrared decoys. Oppressive decoy lures infrared guided missile by its high infrared radiation. Traditional tracking algorithms have degraded stability even come to tracking failure when airborne target continuously throw out many decoys. The proposed approach first determines an adaptive tracking window. The center of the tracking window is set at a predicted target position which is computed based on uniform motion model. Different strategies are applied for determination of tracking window size according to target state. The image within tracking window is segmented and multi features of candidate targets are extracted. The most similar candidate target is associated to the tracking target by using a decision function, which calculates a weighted sum of normalized feature differences between two comparable targets. Integrated intensity ratio of association target and tracking target, and target centroid are examined to estimate target state in the presence of decoys. The tracking ability and robustness of proposed approach has been validated by processing available real-world and simulated infrared image sequences containing airborne targets and oppressive decoys.

The Learning Benefits of Using Eye Trackers to Enhance the Geospatial Abilities of Elementary School Students

ERIC Educational Resources Information Center

Wang, Hsiao-shen; Chen, Yi-Ting; Lin, Chih-Hung

2014-01-01

In this study, we examined the spatial abilities of students using eye-movement tracking devices to identify and analyze their characteristics. For this research, 12 students aged 11-12 years participated as novices and 4 mathematics students participated as experts. A comparison of the visual-spatial abilities of each group showed key factors of…

The role of self-control and cognitive functioning in educational inequalities in adolescent smoking and binge drinking.

PubMed

Davies, Lisa E M; Kuipers, Mirte A G; Junger, Marianne; Kunst, Anton E

2017-09-16

Large differences in substance use between educational levels originate at a young age, but there is limited evidence explaining these inequalities. The aim of this study was to test whether a) smoking and binge drinking are associated with lower levels of self-control and cognitive functioning, and b) associations between educational track and smoking and binge drinking, respectively, are attenuated after controlling for self-control and cognitive functioning. This study used cross-sectional survey data of 15 to 20-year-olds (N = 191) from low, middle, and high educational tracks. We measured regular binge drinking and regular smoking (more than once a month), cognitive functioning (cognitive ability, reaction time and memory span), and self-control. Logistic regression models were used to assess the associations between educational track and smoking and binge drinking controlled for age, gender and social disadvantage, and for self-control and cognitive functioning. According to models that controlled for age, gender and social disadvantage only, respondents in the low educational track were more likely to drink heavily (OR = 3.25, 95% CI = 1.48-7.17) and smoke (OR = 5.74, 95% CI = 2.31-14.29) than adolescents in the high educational track. The association between educational track and binge drinking was hardly reduced after adjustment for self-control and cognitive ability (OR = 2.88, 95% CI = 1.09-7.62). Adjustment for self-control and cognitive functioning, especially cognitive ability, weakened the association between education and smoking (OR = 3.40, 95% CI = 1.11-10.37). However, inequalities in smoking remained significant and substantial. In this study population, pre-existing variations between adolescents in terms of self-control and cognitive functioning played a minor role in educational inequalities in smoking, but not in binge drinking.

Prey-tracking behavior in the invasive terrestrial planarian Platydemus manokwari (Platyhelminthes, Tricladida)

NASA Astrophysics Data System (ADS)

Iwai, Noriko; Sugiura, Shinji; Chiba, Satoshi

2010-11-01

Platydemus manokwari is a broadly distributed invasive terrestrial flatworm that preys heavily on land snails and has been credited with the demise of numerous threatened island faunas. We examined whether P. manokwari tracks the mucus trails of land snail prey, investigated its ability to determine trail direction, and evaluated prey preference among various land snail species. A plastic treatment plate with the mucus trail of a single species and a control plate without the trail were placed side by side at the exit of cages housing P. manokwari. All trials were then videotaped overnight. The flatworms moved along plates with mucus trails, but did not respond to plates without trails, blank control (distilled water), or with conspecific flatworm trails. When presented at the midpoint of a snail mucus trail, the flatworms followed the trail in a random direction. The flatworms showed a preference when choosing between two plates, each with a mucus trail of different land snail species. Our results suggest that P. manokwari follows snail mucus trails based on chemical cues to increase the chance of encountering prey; however, trail-tracking behavior showed no directionality.

The Relationship of Static Tibial Tubercle-Trochlear Groove Measurement and Dynamic Patellar Tracking.

PubMed

Carlson, Victor R; Sheehan, Frances T; Shen, Aricia; Yao, Lawrence; Jackson, Jennifer N; Boden, Barry P

2017-07-01

The tibial tubercle to trochlear groove (TT-TG) distance is used for screening patients with a variety of patellofemoral joint disorders to determine who may benefit from patellar medialization using a tibial tubercle osteotomy. Clinically, the TT-TG distance is predominately based on static imaging with the knee in full extension; however, the predictive ability of this measure for dynamic patellar tracking patterns is unknown. To determine whether the static TT-TG distance can predict dynamic lateral displacement of the patella. Cohort study (Diagnosis); Level of evidence, 2. The static TT-TG distance was measured at full extension for 70 skeletally mature subjects with (n = 32) and without (n = 38) patellofemoral pain. The dynamic patellar tracking patterns were assessed from approximately 45° to 0° of knee flexion by use of dynamic cine-phase contrast magnetic resonance imaging. For each subject, the value of dynamic lateral tracking corresponding to the exact knee angle measured in the static images for that subject was identified. Linear regression analysis determined the predictive ability of static TT-TG distance for dynamic patellar lateral displacement for each cohort. The static TT-TG distance measured with the knee in full extension cannot accurately predict dynamic lateral displacement of the patella. There was weak predictive ability among subjects with patellofemoral pain ( r 2 = 0.18, P = .02) and no predictive capability among controls. Among subjects with patellofemoral pain and static TT-TG distances 15 mm or more, 8 of 13 subjects (62%) demonstrated neutral or medial patellar tracking patterns. The static TT-TG distance cannot accurately predict dynamic lateral displacement of the patella. A large percentage of patients with patellofemoral pain and pathologically large TT-TG distances may have neutral to medial maltracking patterns.

OpenCV and TYZX : video surveillance for tracking.

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Jim; Spencer, Andrew; Chu, Eric

2008-08-01

As part of the National Security Engineering Institute (NSEI) project, several sensors were developed in conjunction with an assessment algorithm. A camera system was developed in-house to track the locations of personnel within a secure room. In addition, a commercial, off-the-shelf (COTS) tracking system developed by TYZX was examined. TYZX is a Bay Area start-up that has developed its own tracking hardware and software which we use as COTS support for robust tracking. This report discusses the pros and cons of each camera system, how they work, a proposed data fusion method, and some visual results. Distributed, embedded image processingmore » solutions show the most promise in their ability to track multiple targets in complex environments and in real-time. Future work on the camera system may include three-dimensional volumetric tracking by using multiple simple cameras, Kalman or particle filtering, automated camera calibration and registration, and gesture or path recognition.« less

Measuring Conditions and Consequences of Tracking in the High School Curriculum

ERIC Educational Resources Information Center

Archbald, Doug; Keleher, Julia

2008-01-01

Despite a decade of advocacy and advances in technology, data driven decision making remains an elusive vision for most high schools. This article identifies key data systems design needs and presents methods for monitoring, managing, and improving programs. Because of its continuing salience, we focus on the issue of tracking (ability grouping).…

The Haskins Optically Corrected Ultrasound System

ERIC Educational Resources Information Center

Whalen, D. H.; Iskarous, Khalil; Tiede, Mark K.; Ostry, David J.; Lehnert-LeHouillier, Heike; Vatikiotis-Bateson, Eric; Hailey, Donald S.

2005-01-01

The tongue is critical in the production of speech, yet its nature has made it difficult to measure. Not only does its ability to attain complex shapes make it difficult to track, it is also largely hidden from view during speech. The present article describes a new combination of optical tracking and ultrasound imaging that allows for a…

77 FR 73493 - Notice of Proposed Information Collection: Comment Request Family Self-Sufficiency Program...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

.... DATES: Comments Due Date: February 8, 2013. ADDRESSES: Interested persons are invited to submit comments... model is needed because participant self-selection into FSS limits the ability to know whether program.... Tracking survey sample 3,000 1 Maximum of 1 hour over 3,000 hours. the tracking period, mainly to update...

Job Grading Standard for Brakeman and Conductor WG-6003.

ERIC Educational Resources Information Center

Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

The standard is used to grade the nonsupervisory work involved in coordinating (onsite) the movement, make up, or break up of trains, locomotives, and train cars. The work requires knowledge of the layout of a railroad track system; knowledge of and ability to follow numerous safety, signalling, switching, track use, train car, and train movement…

78 FR 23291 - United States v. Ecolab Inc., et al.; Proposed Final Judgment and Competitive Impact Statement

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-18

... levels of proposed service personnel. 17. Customers choose a PCMS provider based on a number of factors... track record servicing deepwater wells, and the provider's ability to offer timely and competent service... prospective customers. New entrants can only offer chemical formulations without a track record of success or...

Performance of two quantitative PCR methods for microbial source tracking of human sewage and implications for microbial risk assessment in recreational waters

EPA Science Inventory

Before new, rapid quantitative PCR (qPCR) methods for recreational water quality assessment and microbial source tracking (MST) can be useful in a regulatory context, an understanding of the ability of the method to detect a DNA target (marker) when the contaminant soure has been...

Can Tracking Raise the Test Scores of High-Ability Minority Students?

ERIC Educational Resources Information Center

Card, David; Giuliano, Laura

2016-01-01

We evaluate a tracking program in a large urban district where schools with at least one gifted fourth grader create a separate "gifted/high achiever" classroom. Most seats are filled by non-gifted high achievers, ranked by previous-year test scores. We study the program's effects on the high achievers using (1) a rank-based regression…

Development of DNA-based Identification methods to track the species composition of fish larvae within nearshore areas of the Great Lakes

EPA Science Inventory

The ability to track the identity and abundance of larval fish, which are ubiquitous during spawning season, may lead to a greater understanding of fish species distributions in Great Lakes nearshore areas including early-detection of invasive fish species before they become esta...

Tracking and Student Achievement: The Role of Instruction as a Mediator

ERIC Educational Resources Information Center

Schmidt, Rebecca Anne

2013-01-01

Most public schools and districts must face the problem of how to help low-achieving students and efficiently target resources, particularly in the face of accountability under No Child Left Behind. One policy that has been employed is grouping students into classrooms by their measured or perceived ability--a process known as tracking. Research…

Role of larval host plants in the climate-driven range expansion of the butterfly Polygonia c-album.

PubMed

Braschler, Brigitte; Hill, Jane K

2007-05-01

1. Some species have expanded their ranges during recent climate warming and the availability of breeding habitat and species' dispersal ability are two important factors determining expansions. The exploitation of a wide range of larval host plants should increase an herbivorous insect species' ability to track climate by increasing habitat availability. Therefore we investigated whether the performance of a species on different host plants changed towards its range boundary, and under warmer temperatures. 2. We studied the polyphagous butterfly Polygonia c-album, which is currently expanding its range in Britain and apparently has altered its host plant preference from Humulus lupulus to include other hosts (particularly Ulmus glabra and Urtica dioica). We investigated insect performance (development time, larval growth rate, adult size, survival) and adult flight morphology on these host plants under four rearing temperatures (18-28.5 degrees C) in populations from core and range margin sites. 3. In general, differences between core and margin populations were small compared with effects of rearing temperature and host plant. In terms of insect performance, host plants were generally ranked U. glabra > or = U. dioica > H. lupulus at all temperatures. Adult P. c-album can either enter diapause or develop directly and higher temperatures resulted in more directly developing adults, but lower survival rates (particularly on the original host H. lupulus) and smaller adult size. 4. Adult flight morphology of wild-caught individuals from range margin populations appeared to be related to increased dispersal potential relative to core populations. However, there was no difference in laboratory reared individuals, and conflicting results were obtained for different measures of flight morphology in relation to larval host plant and temperature effects, making conclusions about dispersal potential difficult. 5. Current range expansion of P. c-album is associated with the exploitation of more widespread host plants on which performance is improved. This study demonstrates how polyphagy may enhance the ability of species to track climate change. Our findings suggest that observed differences in climate-driven range shifts of generalist vs. specialist species may increase in the future and are likely to lead to greatly altered community composition.

Effects of measurement unobservability on neural extended Kalman filter tracking

NASA Astrophysics Data System (ADS)

Stubberud, Stephen C.; Kramer, Kathleen A.

2009-05-01

An important component of tracking fusion systems is the ability to fuse various sensors into a coherent picture of the scene. When multiple sensor systems are being used in an operational setting, the types of data vary. A significant but often overlooked concern of multiple sensors is the incorporation of measurements that are unobservable. An unobservable measurement is one that may provide information about the state, but cannot recreate a full target state. A line of bearing measurement, for example, cannot provide complete position information. Often, such measurements come from passive sensors such as a passive sonar array or an electronic surveillance measure (ESM) system. Unobservable measurements will, over time, result in the measurement uncertainty to grow without bound. While some tracking implementations have triggers to protect against the detrimental effects, many maneuver tracking algorithms avoid discussing this implementation issue. One maneuver tracking technique is the neural extended Kalman filter (NEKF). The NEKF is an adaptive estimation algorithm that estimates the target track as it trains a neural network on line to reduce the error between the a priori target motion model and the actual target dynamics. The weights of neural network are trained in a similar method to the state estimation/parameter estimation Kalman filter techniques. The NEKF has been shown to improve target tracking accuracy through maneuvers and has been use to predict target behavior using the new model that consists of the a priori model and the neural network. The key to the on-line adaptation of the NEKF is the fact that the neural network is trained using the same residuals as the Kalman filter for the tracker. The neural network weights are treated as augmented states to the target track. Through the state-coupling function, the weights are coupled to the target states. Thus, if the measurements cause the states of the target track to be unobservable, then the weights of the neural network have unobservable modes as well. In recent analysis, the NEKF was shown to have a significantly larger growth in the eigenvalues of the error covariance matrix than the standard EKF tracker when the measurements were purely bearings-only. This caused detrimental effects to the ability of the NEKF to model the target dynamics. In this work, the analysis is expanded to determine the detrimental effects of bearings-only measurements of various uncertainties on the performance of the NEKF when these unobservable measurements are interlaced with completely observable measurements. This analysis provides the ability to put implementation limitations on the NEKF when bearings-only sensors are present.

Reconfigurable multivariable control law for commercial airplane using a direct digital output feedback design

NASA Technical Reports Server (NTRS)

Ostroff, A. J.; Hueschen, R. M.

1984-01-01

The ability of a pilot to reconfigure the control surfaces on an airplane after a failure, allowing the airplane to recover to a safe condition for landing, becomes more difficult with increasing airplane complexity. Techniques are needed to stabilize and control the airplane immediately after a failure, allowing the pilot time to make longer range decisions. This paper shows a design of a discrete multivariable control law using four controls for the longitudinal channel of a B-737. Single control element failures are allowed in three of the four controls. The four controls design and failure cases are analyzed by means of a digital airplane simulation, with regard to tracking capability and ability to overcome severe windshear and turbulence during the aproach and landing phase of flight.

Neural network fusion capabilities for efficient implementation of tracking algorithms

NASA Astrophysics Data System (ADS)

Sundareshan, Malur K.; Amoozegar, Farid

1997-03-01

The ability to efficiently fuse information of different forms to facilitate intelligent decision making is one of the major capabilities of trained multilayer neural networks that is now being recognized. While development of innovative adaptive control algorithms for nonlinear dynamical plants that attempt to exploit these capabilities seems to be more popular, a corresponding development of nonlinear estimation algorithms using these approaches, particularly for application in target surveillance and guidance operations, has not received similar attention. We describe the capabilities and functionality of neural network algorithms for data fusion and implementation of tracking filters. To discuss details and to serve as a vehicle for quantitative performance evaluations, the illustrative case of estimating the position and velocity of surveillance targets is considered. Efficient target- tracking algorithms that can utilize data from a host of sensing modalities and are capable of reliably tracking even uncooperative targets executing fast and complex maneuvers are of interest in a number of applications. The primary motivation for employing neural networks in these applications comes from the efficiency with which more features extracted from different sensor measurements can be utilized as inputs for estimating target maneuvers. A system architecture that efficiently integrates the fusion capabilities of a trained multilayer neural net with the tracking performance of a Kalman filter is described. The innovation lies in the way the fusion of multisensor data is accomplished to facilitate improved estimation without increasing the computational complexity of the dynamical state estimator itself.

Intravital multiphoton photoconversion with a cell membrane dye.

PubMed

Turcotte, Raphaël; Wu, Juwell W; Lin, Charles P

2017-02-01

Photoconversion, an irreversible shift in a fluorophore emission spectrum after light exposure, is a powerful tool for marking cellular and subcellular compartments and tracking their dynamics in vivo. This paper reports on the photoconversion properties of Di-8-ANEPPS, a commercially available membrane dye. When illuminated with near-infrared femtosecond laser pulses, Di-8-ANEPPS undergoes multiphoton photoconversion as indicated by the supralinear dependence of the conversion rate ρ pc on the incident power (ρpc∝Iexc2.27), and by the ability to photoconvert a thin optical section in a three-dimensional matrix. The characteristic emission spectrum changed from red to blue, and ratiometric analysis on single cells in vitro revealed a 65-fold increase in the blue to red wavelength ratio after photoconversion. The spectral shift is preserved in vivo for hours, making Di-8-ANEPPS a useful dye for intravital cell marking and tracking applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Utility of remote sensing-based surface energy balance models to track water stress in rain-fed switchgrass under dry and wet conditions

USDA-ARS?s Scientific Manuscript database

The ability of remote sensing-based surface energy balance (SEB) models to track water stress in rain-fed switchgrass has not been explored yet. In this paper, the theoretical framework of crop water stress index (CWSI) was utilized to estimate CWSI in rain-fed switchgrass (Panicum virgatum L.) usin...

Using wire shaping techniques and holographic optics to optimize deposition characteristics in wire-based laser cladding.

PubMed

Goffin, N J; Higginson, R L; Tyrer, J R

2016-12-01

In laser cladding, the potential benefits of wire feeding are considerable. Typical problems with the use of powder, such as gas entrapment, sub-100% material density and low deposition rate are all avoided with the use of wire. However, the use of a powder-based source material is the industry standard, with wire-based deposition generally regarded as an academic curiosity. This is because, although wire-based methods have been shown to be capable of superior quality results, the wire-based process is more difficult to control. In this work, the potential for wire shaping techniques, combined with existing holographic optical element knowledge, is investigated in order to further improve the processing characteristics. Experiments with pre-placed wire showed the ability of shaped wire to provide uniformity of wire melting compared with standard round wire, giving reduced power density requirements and superior control of clad track dilution. When feeding with flat wire, the resulting clad tracks showed a greater level of quality consistency and became less sensitive to alterations in processing conditions. In addition, a 22% increase in deposition rate was achieved. Stacking of multiple layers demonstrated the ability to create fully dense, three-dimensional structures, with directional metallurgical grain growth and uniform chemical structure.

Using wire shaping techniques and holographic optics to optimize deposition characteristics in wire-based laser cladding

PubMed Central

Higginson, R. L.; Tyrer, J. R.

2016-01-01

In laser cladding, the potential benefits of wire feeding are considerable. Typical problems with the use of powder, such as gas entrapment, sub-100% material density and low deposition rate are all avoided with the use of wire. However, the use of a powder-based source material is the industry standard, with wire-based deposition generally regarded as an academic curiosity. This is because, although wire-based methods have been shown to be capable of superior quality results, the wire-based process is more difficult to control. In this work, the potential for wire shaping techniques, combined with existing holographic optical element knowledge, is investigated in order to further improve the processing characteristics. Experiments with pre-placed wire showed the ability of shaped wire to provide uniformity of wire melting compared with standard round wire, giving reduced power density requirements and superior control of clad track dilution. When feeding with flat wire, the resulting clad tracks showed a greater level of quality consistency and became less sensitive to alterations in processing conditions. In addition, a 22% increase in deposition rate was achieved. Stacking of multiple layers demonstrated the ability to create fully dense, three-dimensional structures, with directional metallurgical grain growth and uniform chemical structure. PMID:28119550

Approaches, field considerations and problems associated with radio tracking carnivores

USGS Publications Warehouse

Sargeant, A.B.; Amlaner, C. J.; MacDonald, D.W.

1979-01-01

The adaptation of radio tracking to ecological studies was a major technological advance affecting field investigations of animal movements and behavior. Carnivores have been the recipients of much attention with this new technology and study approaches have varied from simple to complex. Equipment performance has much improved over the years, but users still face many difficulties. The beginning of all radio tracking studies should be a precise definition of objectives. Study objectives dictate type of gear required and field procedures. Field conditions affect equipment performance and investigator ability to gather data. Radio tracking carnivores is demanding and generally requires greater time than anticipated. Problems should be expected and planned for in study design. Radio tracking can be an asset in carnivore studies but caution is needed in its application.

Persistence in a Two-Dimensional Moving-Habitat Model.

PubMed

Phillips, Austin; Kot, Mark

2015-11-01

Environmental changes are forcing many species to track suitable conditions or face extinction. In this study, we use a two-dimensional integrodifference equation to analyze whether a population can track a habitat that is moving due to climate change. We model habitat as a simple rectangle. Our model quickly leads to an eigenvalue problem that determines whether the population persists or declines. After surveying techniques to solve the eigenvalue problem, we highlight three findings that impact conservation efforts such as reserve design and species risk assessment. First, while other models focus on habitat length (parallel to the direction of habitat movement), we show that ignoring habitat width (perpendicular to habitat movement) can lead to overestimates of persistence. Dispersal barriers and hostile landscapes that constrain habitat width greatly decrease the population's ability to track its habitat. Second, for some long-distance dispersal kernels, increasing habitat length improves persistence without limit; for other kernels, increasing length is of limited help and has diminishing returns. Third, it is not always best to orient the long side of the habitat in the direction of climate change. Evidence suggests that the kurtosis of the dispersal kernel determines whether it is best to have a long, wide, or square habitat. In particular, populations with platykurtic dispersal benefit more from a wide habitat, while those with leptokurtic dispersal benefit more from a long habitat. We apply our model to the Rocky Mountain Apollo butterfly (Parnassius smintheus).

Limitations to maximum running speed on flat curves.

PubMed

Chang, Young-Hui; Kram, Rodger

2007-03-01

Why is maximal running speed reduced on curved paths? The leading explanation proposes that an increase in lateral ground reaction force necessitates a decrease in peak vertical ground reaction force, assuming that maximum leg extension force is the limiting factor. Yet, no studies have directly measured these forces or tested this critical assumption. We measured maximum sprint velocities and ground reaction forces for five male humans sprinting along a straight track and compared them to sprints along circular tracks of 1, 2, 3, 4 and 6 m radii. Circular track sprint trials were performed either with or without a tether that applied centripetal force to the center of mass. Sprinters generated significantly smaller peak resultant ground reaction forces during normal curve sprinting compared to straight sprinting. This provides direct evidence against the idea that maximum leg extension force is always achieved and is the limiting factor. Use of the tether increased sprint speed, but not to expected values. During curve sprinting, the inside leg consistently generated smaller peak forces compared to the outside leg. Several competing biomechanical constraints placed on the stance leg during curve sprinting likely make the inside leg particularly ineffective at generating the ground reaction forces necessary to attain maximum velocities comparable to straight path sprinting. The ability of quadrupeds to redistribute function across multiple stance legs and decouple these multiple constraints may provide a distinct advantage for turning performance.

Multiple feature fusion via covariance matrix for visual tracking

NASA Astrophysics Data System (ADS)

Jin, Zefenfen; Hou, Zhiqiang; Yu, Wangsheng; Wang, Xin; Sun, Hui

2018-04-01

Aiming at the problem of complicated dynamic scenes in visual target tracking, a multi-feature fusion tracking algorithm based on covariance matrix is proposed to improve the robustness of the tracking algorithm. In the frame-work of quantum genetic algorithm, this paper uses the region covariance descriptor to fuse the color, edge and texture features. It also uses a fast covariance intersection algorithm to update the model. The low dimension of region covariance descriptor, the fast convergence speed and strong global optimization ability of quantum genetic algorithm, and the fast computation of fast covariance intersection algorithm are used to improve the computational efficiency of fusion, matching, and updating process, so that the algorithm achieves a fast and effective multi-feature fusion tracking. The experiments prove that the proposed algorithm can not only achieve fast and robust tracking but also effectively handle interference of occlusion, rotation, deformation, motion blur and so on.

Vehicle active steering control research based on two-DOF robust internal model control

NASA Astrophysics Data System (ADS)

Wu, Jian; Liu, Yahui; Wang, Fengbo; Bao, Chunjiang; Sun, Qun; Zhao, Youqun

2016-07-01

Because of vehicle's external disturbances and model uncertainties, robust control algorithms have obtained popularity in vehicle stability control. The robust control usually gives up performance in order to guarantee the robustness of the control algorithm, therefore an improved robust internal model control(IMC) algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain robustness. The proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model uncertainties. In order to separate the design process of model tracking from the robustness design process, the improved 2 degree of freedom(DOF) robust internal model controller structure is given from the standard Youla parameterization. Simulations of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm, on the basis of a nonlinear vehicle simulation model with a magic tyre model. Results show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance, which can enhance the vehicle stability and handling, regardless of variations of the vehicle model parameters and the external crosswind interferences. Contradiction between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.

Seismographs, sensors, and satellites: Better technology for safer communities

USGS Publications Warehouse

Groat, C.G.

2004-01-01

In the past 25 years, our ability to measure, monitor, and model the processes that lead to natural disasters has increased dramatically. Equally important has been the improvement in our technological capability to communicate information about hazards to those whose lives may be affected. These innovations in tracking and communicating the changes-floods, earthquakes, wildfires, volcanic eruptions-in our dynamic planet, supported by a deeper understanding of earth processes, enable us to expand our predictive capabilities and point the way to a safer future. ?? 2004 Elsevier Ltd. All rights reserved.

Integrated Resilient Aircraft Control Project Full Scale Flight Validation

NASA Technical Reports Server (NTRS)

Bosworth, John T.

2009-01-01

Objective: Provide validation of adaptive control law concepts through full scale flight evaluation. Technical Approach: a) Engage failure mode - destabilizing or frozen surface. b) Perform formation flight and air-to-air tracking tasks. Evaluate adaptive algorithm: a) Stability metrics. b) Model following metrics. Full scale flight testing provides an ability to validate different adaptive flight control approaches. Full scale flight testing adds credence to NASA's research efforts. A sustained research effort is required to remove the road blocks and provide adaptive control as a viable design solution for increased aircraft resilience.

Fluorine-containing nanoemulsions for MRI cell tracking

PubMed Central

Janjic, Jelena M.; Ahrens, Eric T.

2009-01-01

In this article we review the chemistry and nanoemulsion formulation of perfluorocarbons used for in vivo 19F MRI cell tracking. In this application, cells of interest are labeled in culture using a perfluorocarbon nanoemulsion. Labeled cells are introduced into a subject and tracked using 19F MRI or NMR spectroscopy. In the same imaging session, a high-resolution, conventional (1H) image can be used to place the 19F-labeled cells into anatomical context. Perfluorocarbon-based 19F cell tracking is a useful technology because of the high specificity for labeled cells, ability to quantify cell accumulations, and biocompatibility. This technology can be widely applied to studies of inflammation, cellular regenerative medicine, and immunotherapy. PMID:19920872

Variability in clubhead presentation characteristics and ball impact location for golfers' drives.

PubMed

Betzler, Nils F; Monk, Stuart A; Wallace, Eric S; Otto, Steve R

2012-01-01

The purpose of the present study was to analyse the variability in clubhead presentation to the ball and the resulting ball impact location on the club face for a range of golfers of different ability. A total of 285 male and female participants hit multiple shots using one of four proprietary drivers. Self-reported handicap was used to quantify a participant's golfing ability. A bespoke motion capture system and user-written algorithms was used to track the clubhead just before and at impact, measuring clubhead speed, clubhead orientation, and impact location. A Doppler radar was used to measure golf ball speed. Generally, golfers of higher skill (lower handicap) generated increased clubhead speed and increased efficiency (ratio of ball speed to clubhead speed). Non-parametric statistical tests showed that low-handicap golfers exhibit significantly lower variability from shot to shot in clubhead speed, efficiency, impact location, attack angle, club path, and face angle compared with high-handicap golfers.

White matter pathways for prosodic structure building: A case study.

PubMed

Sammler, Daniela; Cunitz, Katrin; Gierhan, Sarah M E; Anwander, Alfred; Adermann, Jens; Meixensberger, Jürgen; Friederici, Angela D

2018-05-11

The relevance of left dorsal and ventral fiber pathways for syntactic and semantic comprehension is well established, while pathways for prosody are little explored. The present study examined linguistic prosodic structure building in a patient whose right arcuate/superior longitudinal fascicles and posterior corpus callosum were transiently compromised by a vasogenic peritumoral edema. Compared to ten matched healthy controls, the patient's ability to detect irregular prosodic structure significantly improved between pre- and post-surgical assessment. This recovery was accompanied by an increase in average fractional anisotropy (FA) in right dorsal and posterior transcallosal fiber tracts. Neither general cognitive abilities nor (non-prosodic) syntactic comprehension nor FA in right ventral and left dorsal fiber tracts showed a similar pre-post increase. Together, these findings suggest a contribution of right dorsal and inter-hemispheric pathways to prosody perception, including the right-dorsal tracking and structuring of prosodic pitch contours that is transcallosally informed by concurrent syntactic information. Copyright © 2018 Elsevier Inc. All rights reserved.

Neural mechanisms of attention become more specialised during infancy: Insights from combined eye tracking and EEG.

PubMed

Kulke, Louisa; Atkinson, Janette; Braddick, Oliver

2017-03-01

The Fixation Shift Paradigm (FSP) measures infants' ability to shift gaze from a central fixation stimulus to a peripheral target (e.g. Hood & Atkinson, 1993: Infant Behavior and Development, 16(4), 405-422). Cortical maturation has been suggested as crucial for the developing ability to shift attention. This study investigated the development of neural mechanisms by combining EEG with simultaneous eye tracking during FSP testing, in typically developing infants aged between 1 and 8 months. The most prominent neural response was a frontal positivity which occurred only in the hemisphere contralateral to the target in the youngest infants but became more ipsilateral with age. This changing lateralisation was associated with improving ability to shift attention (decreasing saccade latencies and fewer 'sticky fixations'-failures to disengage attention from the central target). These findings suggest that the lateralisation of neural responses develops during infancy, possibly due to developing intracortical connections, allowing infants to shift attention more efficiently. Successful use of combined simultaneous remote eye tracking and EEG to measure infant attention shifts. Neural responses involved in attention shifts change in the first year of life. The lateralisation of EEG responses changes with age in the first year of life. Frontal cortex is involved in attention shifts from around 2 months of age. © 2016 Wiley Periodicals, Inc.

Effects of Vertical Direction and Aperture Size on the Perception of Visual Acceleration.

PubMed

Mueller, Alexandra S; González, Esther G; McNorgan, Chris; Steinbach, Martin J; Timney, Brian

2016-02-06

It is not well understood whether the distance over which moving stimuli are visible affects our sensitivity to the presence of acceleration or our ability to track such stimuli. It is also uncertain whether our experience with gravity creates anisotropies in how we detect vertical acceleration and deceleration. To address these questions, we varied the vertical extent of the aperture through which we presented vertically accelerating and decelerating random dot arrays. We hypothesized that observers would better detect and pursue accelerating and decelerating stimuli that extend over larger than smaller distances. In Experiment 1, we tested the effects of vertical direction and aperture size on acceleration and deceleration detection accuracy. Results indicated that detection is better for downward motion and for large apertures, but there is no difference between vertical acceleration and deceleration detection. A control experiment revealed that our manipulation of vertical aperture size affects the ability to track vertical motion. Smooth pursuit is better (i.e., with higher peak velocities) for large apertures than for small apertures. Our findings suggest that the ability to detect vertical acceleration and deceleration varies as a function of the direction and vertical extent over which an observer can track the moving stimulus. © The Author(s) 2016.

Tracking the impact of depression in a perspective-taking task.

PubMed

Ferguson, Heather J; Cane, James

2017-11-01

Research has identified impairments in Theory of Mind (ToM) abilities in depressed patients, particularly in relation to tasks involving empathetic responses and belief reasoning. We aimed to build on this research by exploring the relationship between depressed mood and cognitive ToM, specifically visual perspective-taking ability. High and low depressed participants were eye-tracked as they completed a perspective-taking task, in which they followed the instructions of a 'director' to move target objects (e.g. a "teapot with spots on") around a grid, in the presence of a temporarily-ambiguous competitor object (e.g. a "teapot with stars on"). Importantly, some of the objects in the grid were occluded from the director's (but not the participant's) view. Results revealed no group-based difference in participants' ability to use perspective cues to identify the target object. All participants were faster to select the target object when the competitor was only available to the participant, compared to when the competitor was mutually available to the participant and director. Eye-tracking measures supported this pattern, revealing that perspective directed participants' visual search immediately upon hearing the ambiguous object's name (e.g. "teapot"). We discuss how these results fit with previous studies that have shown a negative relationship between depression and ToM.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shao, Michael; Nemati, Bijan; Zhai, Chengxing

We present an approach that significantly increases the sensitivity for finding and tracking small and fast near-Earth asteroids (NEAs). This approach relies on a combined use of a new generation of high-speed cameras which allow short, high frame-rate exposures of moving objects, effectively 'freezing' their motion, and a computationally enhanced implementation of the 'shift-and-add' data processing technique that helps to improve the signal-to-noise ratio (SNR) for detection of NEAs. The SNR of a single short exposure of a dim NEA is insufficient to detect it in one frame, but by computationally searching for an appropriate velocity vector, shifting successive framesmore » relative to each other and then co-adding the shifted frames in post-processing, we synthetically create a long-exposure image as if the telescope were tracking the object. This approach, which we call 'synthetic tracking,' enhances the familiar shift-and-add technique with the ability to do a wide blind search, detect, and track dim and fast-moving NEAs in near real time. We discuss also how synthetic tracking improves the astrometry of fast-moving NEAs. We apply this technique to observations of two known asteroids conducted on the Palomar 200 inch telescope and demonstrate improved SNR and 10 fold improvement of astrometric precision over the traditional long-exposure approach. In the past 5 yr, about 150 NEAs with absolute magnitudes H = 28 (∼10 m in size) or fainter have been discovered. With an upgraded version of our camera and a field of view of (28 arcmin){sup 2} on the Palomar 200 inch telescope, synthetic tracking could allow detecting up to 180 such objects per night, including very small NEAs with sizes down to 7 m.« less

Within-Hemifield Competition in Early Visual Areas Limits the Ability to Track Multiple Objects with Attention

PubMed Central

Alvarez, George A.; Cavanagh, Patrick

2014-01-01

It is much easier to divide attention across the left and right visual hemifields than within the same visual hemifield. Here we investigate whether this benefit of dividing attention across separate visual fields is evident at early cortical processing stages. We measured the steady-state visual evoked potential, an oscillatory response of the visual cortex elicited by flickering stimuli, of moving targets and distractors while human observers performed a tracking task. The amplitude of responses at the target frequencies was larger than that of the distractor frequencies when participants tracked two targets in separate hemifields, indicating that attention can modulate early visual processing when it is divided across hemifields. However, these attentional modulations disappeared when both targets were tracked within the same hemifield. These effects were not due to differences in task performance, because accuracy was matched across the tracking conditions by adjusting target speed (with control conditions ruling out effects due to speed alone). To investigate later processing stages, we examined the P3 component over central-parietal scalp sites that was elicited by the test probe at the end of the trial. The P3 amplitude was larger for probes on targets than on distractors, regardless of whether attention was divided across or within a hemifield, indicating that these higher-level processes were not constrained by visual hemifield. These results suggest that modulating early processing stages enables more efficient target tracking, and that within-hemifield competition limits the ability to modulate multiple target representations within the hemifield maps of the early visual cortex. PMID:25164651

Can Individuals with Autism Abstract Prototypes of Natural Faces?

ERIC Educational Resources Information Center

Gastgeb, Holly Zajac; Wilkinson, Desiree A.; Minshew, Nancy J.; Strauss, Mark S.

2011-01-01

There is a growing amount of evidence suggesting that individuals with autism have difficulty with face processing. One basic cognitive ability that may underlie face processing difficulties is the ability to abstract a prototype. The current study examined prototype formation with natural faces using eye-tracking in high-functioning adults with…

Naming Giftedness: Whiteness and Ability Discourse in US Schools

ERIC Educational Resources Information Center

Stark, Lauren

2014-01-01

This paper offers a conceptual analysis of ability discourse using the theoretical lens of critical whiteness studies and the methodological framework of critical discourse analysis. From its origins in the Progressive Era to contemporary debates on tracking, the concept of giftedness has been formed through racial projects throughout US history.…

School Organisational Efforts in Search for Alternatives to Ability Grouping

ERIC Educational Resources Information Center

Alpert, Bracha; Bechar, Shlomit

2008-01-01

The paper presents a case study of a secondary school in Israel and its efforts at attending to students' needs without resorting to tracking and ability grouping. It explores an organisational process the school has established, called "Opening triads", which involves periodical regrouping of three classrooms of students of the same age…

Difficulties in Interpreting Ballast Degradation Level Estimates from Synthetic Ground-Penetrating Radar Data

NASA Astrophysics Data System (ADS)

Scanlan, K. M.; Hendry, M. T.; Martin, C. D.; Schmitt, D. R.

2016-12-01

As fine-grained particles accumulate within railway ballast, it becomes more susceptible to differential deformations, which leads to the loss of proper track alignment and an increased risk for car derailment. Methods for estimating the ballast degradation level from low-frequency (<1 GHz) ground-penetrating radar (GPR) measurements exist, but their applicability in a wide range of track foundation conditions has yet to be evaluated. This analysis, based on simulated GPR data, evaluates the sensitivity of these methods to changing ballast moisture contents, ballast thicknesses and subballast material types. The results highlight that small changes to the track foundation, indepedent of the concentration of degraded ballast, significantly alter the attenuation and reflectivity characteristics of the simualted GPR measurements. As such, ballast degraded to a certain level will manifest with different attenuation and reflectivity characteristics, limiting the ability to accurately and reliably detect these changes using GPR. Radar propagation velocities within the ballast are less influenced by changes in ballast depth and subballast material type. However, ambiguous propagation velocities are observed for certain ballast moisture contents and degradation levels; furthermore, velocities can only be calculated when the ballast thickness is known. These results suggest that while under certain circumstances, with additional information on the track foundation conditons, ballast degradation levels can be estimated from GPR data; in general, the complicated nature of GPR signals makes the quantificaion of ballast degradation levels difficult.

Interactive Multiple Object Tracking (iMOT)

PubMed Central

Thornton, Ian M.; Bülthoff, Heinrich H.; Horowitz, Todd S.; Rynning, Aksel; Lee, Seong-Whan

2014-01-01

We introduce a new task for exploring the relationship between action and attention. In this interactive multiple object tracking (iMOT) task, implemented as an iPad app, participants were presented with a display of multiple, visually identical disks which moved independently. The task was to prevent any collisions during a fixed duration. Participants could perturb object trajectories via the touchscreen. In Experiment 1, we used a staircase procedure to measure the ability to control moving objects. Object speed was set to 1°/s. On average participants could control 8.4 items without collision. Individual control strategies were quite variable, but did not predict overall performance. In Experiment 2, we compared iMOT with standard MOT performance using identical displays. Object speed was set to 2°/s. Participants could reliably control more objects (M = 6.6) than they could track (M = 4.0), but performance in the two tasks was positively correlated. In Experiment 3, we used a dual-task design. Compared to single-task baseline, iMOT performance decreased and MOT performance increased when the two tasks had to be completed together. Overall, these findings suggest: 1) There is a clear limit to the number of items that can be simultaneously controlled, for a given speed and display density; 2) participants can control more items than they can track; 3) task-relevant action appears not to disrupt MOT performance in the current experimental context. PMID:24498288

Changes in Muscle Architecture, Explosive Ability, and Track and Field Throwing Performance Throughout a Competitive Season and After a Taper.

PubMed

Bazyler, Caleb D; Mizuguchi, Satoshi; Harrison, Alex P; Sato, Kimitake; Kavanaugh, Ashley A; DeWeese, Brad H; Stone, Michael H

2017-10-01

The purpose of this study was to examine the effects of an overreach and taper on measures of muscle architecture, jumping, and throwing performance in Division I collegiate throwers preparing for conference championships. Six collegiate track and field throwers (3 hammer, 2 discus, 1 javelin) trained for 12 weeks using a block-periodization model culminating with a 1-week overreach followed by a 3-week taper (ORT). Session rating of perceived exertion training load (RPETL) and strength training volume-load times bar displacement (VLd) were recorded weekly. Athletes were tested pre-ORT and post-ORT on measures of vastus lateralis architecture, unloaded and loaded squat and countermovement jump performance, underhand and overhead throwing performance, and competition throwing performance. There was a statistical reduction in weight training VLd/session (d = 1.21, p ≤ 0.05) and RPETL/session (d = 0.9, p ≤ 0.05) between the in-season and ORT training phases. Five of 6 athletes improved overhead throw and competition throwing performance after the ORT (d = 0.50, p ≤ 0.05). Vastus lateralis muscle thickness statistically increased after the in-season training phase (d = 0.28, p ≤ 0.05) but did not change after the ORT. Unloaded countermovement jump peak force and relative peak power improved significantly after the ORT (d = 0.59, p ≤ 0.05, d = 0.31, p ≤ 0.05, respectively). These findings demonstrate that an overreaching week followed by a 3-week taper is an effective means of improving explosive ability and throwing performance in collegiate track and field throwers despite the absence of detectable changes in muscle architecture.

Cerebellum Augmented Rover Development

NASA Technical Reports Server (NTRS)

King, Matthew

2005-01-01

Bio-Inspired Technologies and Systems (BITS) are a very natural result of thinking about Nature's way of solving problems. Knowledge of animal behaviors an be used in developing robotic behaviors intended for planetary exploration. This is the expertise of the JFL BITS Group and has served as a philosophical model for NMSU RioRobolab. Navigation is a vital function for any autonomous system. Systems must have the ability to determine a safe path between their current location and some target location. The MER mission, as well as other JPL rover missions, uses a method known as dead-reckoning to determine position information. Dead-reckoning uses wheel encoders to sense the wheel's rotation. In a sandy environment such as Mars, this method is highly inaccurate because the wheels will slip in the sand. Improving positioning error will allow the speed of an autonomous navigating rover to be greatly increased. Therefore, local navigation based upon landmark tracking is desirable in planetary exploration. The BITS Group is developing navigation technology based upon landmark tracking. Integration of the current rover architecture with a cerebellar neural network tracking algorithm will demonstrate that this approach to navigation is feasible and should be implemented in future rover and spacecraft missions.

Contrast, contours and the confusion effect in dazzle camouflage.

PubMed

Hogan, Benedict G; Scott-Samuel, Nicholas E; Cuthill, Innes C

2016-07-01

'Motion dazzle camouflage' is the name for the putative effects of highly conspicuous, often repetitive or complex, patterns on parameters important in prey capture, such as the perception of speed, direction and identity. Research into motion dazzle camouflage is increasing our understanding of the interactions between visual tracking, the confusion effect and defensive coloration. However, there is a paucity of research into the effects of contrast on motion dazzle camouflage: is maximal contrast a prerequisite for effectiveness? If not, this has important implications for our recognition of the phenotype and understanding of the function and mechanisms of potential motion dazzle camouflage patterns. Here we tested human participants' ability to track one moving target among many identical distractors with surface patterns designed to test the influence of these factors. In line with previous evidence, we found that targets with stripes parallel to the object direction of motion were hardest to track. However, reduction in contrast did not significantly influence this result. This finding may bring into question the utility of current definitions of motion dazzle camouflage, and means that some animal patterns, such as aposematic or mimetic stripes, may have previously unrecognized multiple functions.

2-D Myocardial Deformation Imaging Based on RF-Based Nonrigid Image Registration.

PubMed

Chakraborty, Bidisha; Liu, Zhi; Heyde, Brecht; Luo, Jianwen; D'hooge, Jan

2018-06-01

Myocardial deformation imaging is a well-established echocardiographic technique for the assessment of myocardial function. Although some solutions make use of speckle tracking of the reconstructed B-mode images, others apply block matching (BM) on the underlying radio frequency (RF) data in order to increase sensitivity to small interframe motion and deformation. However, for both approaches, lateral motion estimation remains a challenge due to the relatively poor lateral resolution of the ultrasound image in combination with the lack of phase information in this direction. Hereto, nonrigid image registration (NRIR) of B-mode images has previously been proposed as an attractive solution. However, hereby, the advantages of RF-based tracking were lost. The aim of this paper was, therefore, to develop an NRIR motion estimator adapted to RF data sets. The accuracy of this estimator was quantified using synthetic data and was contrasted against a state-of-the-art BM solution. The results show that RF-based NRIR outperforms BM in terms of tracking accuracy, particularly, as hypothesized, in the lateral direction. Finally, this RF-based NRIR algorithm was applied clinically, illustrating its ability to estimate both in-plane velocity components in vivo.

Feasibility of spatial frequency domain imaging (SFDI) for optically characterizing a preclinical oncology model.

PubMed

Tabassum, Syeda; Zhao, Yanyu; Istfan, Raeef; Wu, Junjie; Waxman, David J; Roblyer, Darren

2016-10-01

Determination of chemotherapy efficacy early during treatment would provide more opportunities for physicians to alter and adapt treatment plans. Diffuse optical technologies may be ideally suited to track early biological events following chemotherapy administration due to low cost and high information content. We evaluated the use of spatial frequency domain imaging (SFDI) to characterize a small animal tumor model in order to move towards the goal of endogenous optical monitoring of cancer therapy in a controlled preclinical setting. The effects of key measurement parameters including the choice of imaging spatial frequency and the repeatability of measurements were evaluated. The precision of SFDI optical property extractions over repeat mouse measurements was determined to be within 3.52% for move and replace experiments. Baseline optical properties and chromophore values as well as intratumor heterogeneity were evaluated over 25 tumors. Additionally, tumor growth and chemotherapy response were monitored over a 45 day longitudinal study in a small number of mice to demonstrate the ability of SFDI to track treatment effects. Optical scattering and oxygen saturation increased as much as 70% and 25% respectively in treated tumors, suggesting SFDI may be useful for preclinical tracking of cancer therapies.

An Improved Wake Vortex Tracking Algorithm for Multiple Aircraft

NASA Technical Reports Server (NTRS)

Switzer, George F.; Proctor, Fred H.; Ahmad, Nashat N.; LimonDuparcmeur, Fanny M.

2010-01-01

The accurate tracking of vortex evolution from Large Eddy Simulation (LES) data is a complex and computationally intensive problem. The vortex tracking requires the analysis of very large three-dimensional and time-varying datasets. The complexity of the problem is further compounded by the fact that these vortices are embedded in a background turbulence field, and they may interact with the ground surface. Another level of complication can arise, if vortices from multiple aircrafts are simulated. This paper presents a new technique for post-processing LES data to obtain wake vortex tracks and wake intensities. The new approach isolates vortices by defining "regions of interest" (ROI) around each vortex and has the ability to identify vortex pairs from multiple aircraft. The paper describes the new methodology for tracking wake vortices and presents application of the technique for single and multiple aircraft.

Active Multimodal Sensor System for Target Recognition and Tracking

PubMed Central

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

2017-01-01

High accuracy target recognition and tracking systems using a single sensor or a passive multisensor set are susceptible to external interferences and exhibit environmental dependencies. These difficulties stem mainly from limitations to the available imaging frequency bands, and a general lack of coherent diversity of the available target-related data. This paper proposes an active multimodal sensor system for target recognition and tracking, consisting of a visible, an infrared, and a hyperspectral sensor. The system makes full use of its multisensor information collection abilities; furthermore, it can actively control different sensors to collect additional data, according to the needs of the real-time target recognition and tracking processes. This level of integration between hardware collection control and data processing is experimentally shown to effectively improve the accuracy and robustness of the target recognition and tracking system. PMID:28657609

Complex Feeding Tracks of the Sessile Herbivorous Insect Ophiomyia maura as a Function of the Defense against Insect Parasitoids

PubMed Central

Ayabe, Yoshiko; Ueno, Takatoshi

2012-01-01

Because insect herbivores generally suffer from high mortality due to their natural enemies, reducing the risk of being located by natural enemies is of critical importance for them, forcing them to develop a variety of defensive measures. Larvae of leaf-mining insects lead a sedentary life inside a leaf and make conspicuous feeding tracks called mines, exposing themselves to the potential risk of parasitism. We investigated the defense strategy of the linear leafminer Ophiomyia maura Meigen (Diptera: Agromyzidae), by focusing on its mining patterns. We examined whether the leafminer could reduce the risk of being parasitized (1) by making cross structures in the inner area of a leaf to deter parasitoids from tracking the mines due to complex pathways, and (2) by mining along the edge of a leaf to hinder visually searching parasitoids from finding mined leaves due to effective background matching of the mined leaves among intact leaves. We quantified fractal dimension as mine complexity and area of mine in the inner area of the leaf as interior mine density for each sample mine, and analyzed whether these mine traits affected the susceptibility of O. maura to parasitism. Our results have shown that an increase in mine complexity with the development of occupying larvae decreases the probability of being parasitized, while interior mine density has no influence on parasitism. These results suggest that the larval development increases the host defense ability through increasing mine complexity. Thus the feeding pattern of these sessile insects has a defensive function by reducing the risk of parasitism. PMID:22393419

Unraveling bacterial networks and their antimicrobial susceptibility on silicon microarchitectures using intrinsic phase-shift spectroscopy

NASA Astrophysics Data System (ADS)

Leonard, Heidi; Holtzman, Liran; Haimov, Yuri; Weizman, Daniel; Kashi, Yechezkel; Nativ, Ofer; Halachmi, Sarel; Segal, Ester

2018-02-01

We have developed a rapid phenotypic antimicrobial susceptibility testing (AST) in which photonic 2D silicon microarrays are employed as both the optical transducer element and as a preferable solid-liquid interface for bacterial colonization. We harness the intrinsic ability of the micro-architectures to relay optical phase-shift reflectometric interference spectroscopic measurements (termed PRISM) and incorporate it into a platform for culture-free, label-free tracking of bacterial accumulation, proliferation, and death. This assay employs microfluidic channels interfaced with PRISM chips and is carried out in a two-stage process, namely bacteria seeding and antibiotic incubation. Bacteria proliferation within the microtopologies results in an increase in refractive index of the medium, yielding an increase in optical path difference, while cell death or bacteriostatic activity results in decreasing or unchanged values. The optical responses of bacteria to various concentrations of relevant antibiotics have been tracked in real time, allowing for accurate determination of the minimum inhibitory concentration (MIC) values within 2-3 hours. We further extended this work to analyze antibiotic susceptibilities of clinical isolates and direct urine samples derived from patients at neighboring hospitals in newly designed, disposable microfluidic devices. This has opened the door to the observation of unique bacterial behaviors, as we can evaluate bacterial adhesion, growth, and antibiotic resistance on different microarchitectures, different surface chemistries, and even different strains. Motility, charge, and biofilm abilities have been explored for their effect of bacterial adhesion to the microstructures as we further develop our method of rapid, label-free AST for full clinical application.

The performance of matched-field track-before-detect methods using shallow-water Pacific data.

PubMed

Tantum, Stacy L; Nolte, Loren W; Krolik, Jeffrey L; Harmanci, Kerem

2002-07-01

Matched-field track-before-detect processing, which extends the concept of matched-field processing to include modeling of the source dynamics, has recently emerged as a promising approach for maintaining the track of a moving source. In this paper, optimal Bayesian and minimum variance beamforming track-before-detect algorithms which incorporate a priori knowledge of the source dynamics in addition to the underlying uncertainties in the ocean environment are presented. A Markov model is utilized for the source motion as a means of capturing the stochastic nature of the source dynamics without assuming uniform motion. In addition, the relationship between optimal Bayesian track-before-detect processing and minimum variance track-before-detect beamforming is examined, revealing how an optimal tracking philosophy may be used to guide the modification of existing beamforming techniques to incorporate track-before-detect capabilities. Further, the benefits of implementing an optimal approach over conventional methods are illustrated through application of these methods to shallow-water Pacific data collected as part of the SWellEX-1 experiment. The results show that incorporating Markovian dynamics for the source motion provides marked improvement in the ability to maintain target track without the use of a uniform velocity hypothesis.

(abstract) Two-Dimensional Surface Current in the Coastal Environment Using Vector Along-Track Interferometry

NASA Technical Reports Server (NTRS)

Rodriguez, Ernesto; Imel, David; Houshmand, Bijan; Carande, Richard

1994-01-01

The structure of surface currents in the coastal environment can be very complex as it is governed by a multitude of factors such as local bathymetry, sea state, etc. Knowledge of the structure of coastal currents is a key requirement in the ability to carry out safe maneuvers and landings in an unknown coastal situation. Furthermore, it is desirable to have the ability to obtain such information by remote sensing and in a timely manner. We present a remote sensing technique which has the potential to meet certain specific requisites. We will present a theoretical discussion of the measurement technique, then will demonstrate the technique using data previously acquired and compare the results against conventional along-track interferometric measurements.

Generation of Simulated Tracking Data for LADEE Operational Readiness Testing

NASA Technical Reports Server (NTRS)

Woodburn, James; Policastri, Lisa; Owens, Brandon

2015-01-01

Operational Readiness Tests were an important part of the pre-launch preparation for the LADEE mission. The generation of simulated tracking data to stress the Flight Dynamics System and the Flight Dynamics Team was important for satisfying the testing goal of demonstrating that the software and the team were ready to fly the operational mission. The simulated tracking was generated in a manner to incorporate the effects of errors in the baseline dynamical model, errors in maneuver execution and phenomenology associated with various tracking system based components. The ability of the mission team to overcome these challenges in a realistic flight dynamics scenario indicated that the team and flight dynamics system were ready to fly the LADEE mission. Lunar Atmosphere and Dust Environment.

A Mobile GPS Application: Mosque Tracking with Prayer Time Synchronization

NASA Astrophysics Data System (ADS)

Hashim, Rathiah; Ikhmatiar, Mohammad Sibghotulloh; Surip, Miswan; Karmin, Masiri; Herawan, Tutut

Global Positioning System (GPS) is a popular technology applied in many areas and embedded in many devices, facilitating end-users to navigate effectively to user's intended destination via the best calculated route. The ability of GPS to track precisely according to coordinates of specific locations can be utilized to assist a Muslim traveler visiting or passing an unfamiliar place to find the nearest mosque in order to perform his prayer. However, not many techniques have been proposed for Mosque tracking. This paper presents the development of GPS technology in tracking the nearest mosque using mobile application software embedded with the prayer time's synchronization system on a mobile application. The prototype GPS system developed has been successfully incorporated with a map and several mosque locations.

Learners' Strategies with a Grammar Application: The Influence of Language Ability and Personality Preferences

ERIC Educational Resources Information Center

Hwu, Fenfang

2007-01-01

This case study investigated the ways pre-major and pre-minor students of Spanish interacted with a grammar application from four perspectives. Firstly, using the computer's tracking ability to collect learners' behaviors, the study set out to uncover the different ways learners approached the application. Secondly, the study assessed the…

Numerosity and Number Signs in Deaf Nicaraguan Adults

ERIC Educational Resources Information Center

Flaherty, Molly; Senghas, Ann

2011-01-01

What abilities are entailed in being numerate? Certainly, one is the ability to hold the exact quantity of a set in mind, even as it changes, and even after its members can no longer be perceived. Is counting language necessary to track and reproduce exact quantities? Previous work with speakers of languages that lack number words involved…

An Examination of the Influences of a Teacher Preparation Program on Beginning Teachers' Reading Instruction

ERIC Educational Resources Information Center

Clark, Sarah K.; Jones, Cindy D.; Reutzel, D. Ray; Andreasen, Lindi

2013-01-01

In this study, we tracked elementary preservice teachers' (N = 41) perceived ability to teach reading as they moved through their teacher preparation program. After graduation, we conducted follow-up teaching observations and interviews with five of these novice teachers to explore their perceptions about their ability to teach reading. An…

Sentinel-5/UVNS instrument: the principle ability of a slit homogenizer to reduce scene contrast for earth observation spectrometer

NASA Astrophysics Data System (ADS)

Meister, Ch.; Keim, C.; Irizar, J.; Bauer, M.

2017-09-01

Sentinel-5/UVNS 1 is an Earth observation spectrometer system that is operating in nadir looking push broom mode from a low Earth orbit. While having a wide across-track field of view (≈ 2700 km) it covers approximately 7 km at nadir in flight direction during one dwell. However a high contrast in the scene in along track may lead to disturbance of the Instrument Spectral Response Function (ISRF) and with this a variation of measured spectrum. In order to reduce the effect of scene contrast along track, instead of a spectrometer slit two mirrors are introduced, in between which the light path is extended such as a one dimensional wave guide. The entrance length across track however is wide enough to let light pass unchanged. This new concept is called Slit Homogenizer (SH) within theSentinel-5 project. The entrance of the SH is placed on the image plane of the preceding op- tics. The exit of the SH represents the object plane of the subsequent spectrometer in the along track (spectral) direction. This article proposes a simulation model of a SH together with a preced- ing generic optics based on scalar diffraction theory. The model is used to evaluate quantitatively the homogenizing ability of the device. Some parameters in the discussed examples are taken from Sentinel-5/UVNS instrument but the model and its application is not limited to that mission.

Will changes in phenology track climate change? A study of growth initiation timing in coast Douglas-fir

Treesearch

Kevin Ford; Connie Harrington; Sheel Bansal; Peter J. Gould; Brad St. Clair

2016-01-01

Under climate change, the reduction of frost risk, onset of warm temperatures and depletion of soil moisture are all likely to occur earlier in the year in many temperate regions. The resilience of tree species will depend on their ability to track these changes in climate with shifts in phenology that lead to earlier growth initiation in the spring. Exposure to warm...

Eye-Tracking as a Tool to Evaluate Functional Ability in Everyday Tasks in Glaucoma.

PubMed

Kasneci, Enkelejda; Black, Alex A; Wood, Joanne M

2017-01-01

To date, few studies have investigated the eye movement patterns of individuals with glaucoma while they undertake everyday tasks in real-world settings. While some of these studies have reported possible compensatory gaze patterns in those with glaucoma who demonstrated good task performance despite their visual field loss, little is known about the complex interaction between field loss and visual scanning strategies and the impact on task performance and, consequently, on quality of life. We review existing approaches that have quantified the effect of glaucomatous visual field defects on the ability to undertake everyday activities through the use of eye movement analysis. Furthermore, we discuss current developments in eye-tracking technology and the potential for combining eye-tracking with virtual reality and advanced analytical approaches. Recent technological developments suggest that systems based on eye-tracking have the potential to assist individuals with glaucomatous loss to maintain or even improve their performance on everyday tasks and hence enhance their long-term quality of life. We discuss novel approaches for studying the visual search behavior of individuals with glaucoma that have the potential to assist individuals with glaucoma, through the use of personalized programs that take into consideration the individual characteristics of their remaining visual field and visual search behavior.

SU-G-BRA-06: Quantification of Tracking Performance of a Multi-Layer Electronic Portal Imaging Device

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Y; Rottmann, J; Myronakis, M

2016-06-15

Purpose: The purpose of this study was to quantify the improvement in tumor tracking, with and without fiducial markers, afforded by employing a multi-layer (MLI) electronic portal imaging device (EPID) over the current state-of-the-art, single-layer, digital megavolt imager (DMI) architecture. Methods: An ideal observer signal-to-noise ratio (d’) approach was used to quantify the ability of an MLI EPID and a current, state-of-the-art DMI EPID to track lung tumors from the treatment beam’s-eye-view. Using each detector modulation transfer function (MTF) and noise power spectrum (NPS) as inputs, a detection task was employed with object functions describing simple three-dimensional Cartesian shapes (spheresmore » and cylinders). Marker-less tumor tracking algorithms often use texture discrimination to differentiate benign and malignant tissue. The performance of such algorithms is simulated by employing a discrimination task for the ideal observer, which measures the ability of a system to differentiate two image quantities. These were defined as the measured textures for benign and malignant lung tissue. Results: The NNPS of the MLI ∼25% of that of the DMI at the expense of decreased MTF at intermediate frequencies (0.25≤« less

Eye-Tracking as a Tool to Evaluate Functional Ability in Everyday Tasks in Glaucoma

PubMed Central

Black, Alex A.

2017-01-01

To date, few studies have investigated the eye movement patterns of individuals with glaucoma while they undertake everyday tasks in real-world settings. While some of these studies have reported possible compensatory gaze patterns in those with glaucoma who demonstrated good task performance despite their visual field loss, little is known about the complex interaction between field loss and visual scanning strategies and the impact on task performance and, consequently, on quality of life. We review existing approaches that have quantified the effect of glaucomatous visual field defects on the ability to undertake everyday activities through the use of eye movement analysis. Furthermore, we discuss current developments in eye-tracking technology and the potential for combining eye-tracking with virtual reality and advanced analytical approaches. Recent technological developments suggest that systems based on eye-tracking have the potential to assist individuals with glaucomatous loss to maintain or even improve their performance on everyday tasks and hence enhance their long-term quality of life. We discuss novel approaches for studying the visual search behavior of individuals with glaucoma that have the potential to assist individuals with glaucoma, through the use of personalized programs that take into consideration the individual characteristics of their remaining visual field and visual search behavior. PMID:28293433

Track Everything: Limiting Prior Knowledge in Online Multi-Object Recognition.

PubMed

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.

Robust infrared targets tracking with covariance matrix representation

NASA Astrophysics Data System (ADS)

Cheng, Jian

2009-07-01

Robust infrared target tracking is an important and challenging research topic in many military and security applications, such as infrared imaging guidance, infrared reconnaissance, scene surveillance, etc. To effectively tackle the nonlinear and non-Gaussian state estimation problems, particle filtering is introduced to construct the theory framework of infrared target tracking. Under this framework, the observation probabilistic model is one of main factors for infrared targets tracking performance. In order to improve the tracking performance, covariance matrices are introduced to represent infrared targets with the multi-features. The observation probabilistic model can be constructed by computing the distance between the reference target's and the target samples' covariance matrix. Because the covariance matrix provides a natural tool for integrating multiple features, and is scale and illumination independent, target representation with covariance matrices can hold strong discriminating ability and robustness. Two experimental results demonstrate the proposed method is effective and robust for different infrared target tracking, such as the sensor ego-motion scene, and the sea-clutter scene.

Evaluation of 2 cognitive abilities tests in a dual-task environment

NASA Technical Reports Server (NTRS)

Vidulich, M. A.; Tsang, P. S.

1986-01-01

Most real world operators are required to perform multiple tasks simultaneously. In some cases, such as flying a high performance aircraft or trouble shooting a failing nuclear power plant, the operator's ability to time share or process in parallel" can be driven to extremes. This has created interest in selection tests of cognitive abilities. Two tests that have been suggested are the Dichotic Listening Task and the Cognitive Failures Questionnaire. Correlations between these test results and time sharing performance were obtained and the validity of these tests were examined. The primary task was a tracking task with dynamically varying bandwidth. This was performed either alone or concurrently with either another tracking task or a spatial transformation task. The results were: (1) An unexpected negative correlation was detected between the two tests; (2) The lack of correlation between either test and task performance made the predictive utility of the tests scores appear questionable; (3) Pilots made more errors on the Dichotic Listening Task than college students.

Within-hemifield competition in early visual areas limits the ability to track multiple objects with attention.

PubMed

Störmer, Viola S; Alvarez, George A; Cavanagh, Patrick

2014-08-27

It is much easier to divide attention across the left and right visual hemifields than within the same visual hemifield. Here we investigate whether this benefit of dividing attention across separate visual fields is evident at early cortical processing stages. We measured the steady-state visual evoked potential, an oscillatory response of the visual cortex elicited by flickering stimuli, of moving targets and distractors while human observers performed a tracking task. The amplitude of responses at the target frequencies was larger than that of the distractor frequencies when participants tracked two targets in separate hemifields, indicating that attention can modulate early visual processing when it is divided across hemifields. However, these attentional modulations disappeared when both targets were tracked within the same hemifield. These effects were not due to differences in task performance, because accuracy was matched across the tracking conditions by adjusting target speed (with control conditions ruling out effects due to speed alone). To investigate later processing stages, we examined the P3 component over central-parietal scalp sites that was elicited by the test probe at the end of the trial. The P3 amplitude was larger for probes on targets than on distractors, regardless of whether attention was divided across or within a hemifield, indicating that these higher-level processes were not constrained by visual hemifield. These results suggest that modulating early processing stages enables more efficient target tracking, and that within-hemifield competition limits the ability to modulate multiple target representations within the hemifield maps of the early visual cortex. Copyright © 2014 the authors 0270-6474/14/3311526-08$15.00/0.

Active controllers and the time duration to learn a task

NASA Technical Reports Server (NTRS)

Repperger, D. W.; Goodyear, C.

1986-01-01

An active controller was used to help train naive subjects involved in a compensatory tracking task. The controller is called active in this context because it moves the subject's hand in a direction to improve tracking. It is of interest here to question whether the active controller helps the subject to learn a task more rapidly than the passive controller. Six subjects, inexperienced to compensatory tracking, were run to asymptote root mean square error tracking levels with an active controller or a passive controller. The time required to learn the task was defined several different ways. The results of the different measures of learning were examined across pools of subjects and across controllers using statistical tests. The comparison between the active controller and the passive controller as to their ability to accelerate the learning process as well as reduce levels of asymptotic tracking error is reported here.

A Comparison of Student Spatial Abilities Across STEM Fields

NASA Astrophysics Data System (ADS)

Loftis, Thad; Cid, Xiimena; Lopez, Ramon

2011-10-01

It has been shown that STEM (Science, Technology, Engineering, and Mathematics) students have higher spatial abilities than students in the liberal arts or humanities. In order to track the change in spatial abilities within a group, studies in physics have examined topics in kinematics, chemistry has examined topics on molecular diagrams, mathematics has examined topics related to geometry, and engineering has developed courses specifically targeting students' spatial abilities. It is understood that students in STEM fields improve their spatial abilities while taking STEM courses, but very few studies have done comparisons amongst the different STEM fields. I will be presenting data comparing different STEM students' spatial ability, assessed using the Mental Rotation Test.

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

Dispersal will limit ability of mammals to track climate change in the Western Hemisphere

PubMed Central

Schloss, Carrie A.; Nuñez, Tristan A.; Lawler, Joshua J.

2012-01-01

As they have in response to past climatic changes, many species will shift their distributions in response to modern climate change. However, due to the unprecedented rapidity of projected climatic changes, some species may not be able to move their ranges fast enough to track shifts in suitable climates and associated habitats. Here, we investigate the ability of 493 mammals to keep pace with projected climatic changes in the Western Hemisphere. We modeled the velocities at which species will likely need to move to keep pace with projected changes in suitable climates. We compared these velocities with the velocities at which species are able to move as a function of dispersal distances and dispersal frequencies. Across the Western Hemisphere, on average, 9.2% of mammals at a given location will likely be unable to keep pace with climate change. In some places, up to 39% of mammals may be unable to track shifts in suitable climates. Eighty-seven percent of mammalian species are expected to experience reductions in range size and 20% of these range reductions will likely be due to limited dispersal abilities as opposed to reductions in the area of suitable climate. Because climate change will likely outpace the response capacity of many mammals, mammalian vulnerability to climate change may be more extensive than previously anticipated. PMID:22586104

Multiplexed single-molecule force spectroscopy using a centrifuge.

PubMed

Yang, Darren; Ward, Andrew; Halvorsen, Ken; Wong, Wesley P

2016-03-17

We present a miniature centrifuge force microscope (CFM) that repurposes a benchtop centrifuge for high-throughput single-molecule experiments with high-resolution particle tracking, a large force range, temperature control and simple push-button operation. Incorporating DNA nanoswitches to enable repeated interrogation by force of single molecular pairs, we demonstrate increased throughput, reliability and the ability to characterize population heterogeneity. We perform spatiotemporally multiplexed experiments to collect 1,863 bond rupture statistics from 538 traceable molecular pairs in a single experiment, and show that 2 populations of DNA zippers can be distinguished using per-molecule statistics to reduce noise.

Multiplexed single-molecule force spectroscopy using a centrifuge

PubMed Central

Yang, Darren; Ward, Andrew; Halvorsen, Ken; Wong, Wesley P.

2016-01-01

We present a miniature centrifuge force microscope (CFM) that repurposes a benchtop centrifuge for high-throughput single-molecule experiments with high-resolution particle tracking, a large force range, temperature control and simple push-button operation. Incorporating DNA nanoswitches to enable repeated interrogation by force of single molecular pairs, we demonstrate increased throughput, reliability and the ability to characterize population heterogeneity. We perform spatiotemporally multiplexed experiments to collect 1,863 bond rupture statistics from 538 traceable molecular pairs in a single experiment, and show that 2 populations of DNA zippers can be distinguished using per-molecule statistics to reduce noise. PMID:26984516

Photometric Mapping of Two Kepler Eclipsing Binaries: KIC11560447 and KIC8868650

NASA Astrophysics Data System (ADS)

Senavci, Hakan Volkan; Özavci, I.; Isik, E.; Hussain, G. A. J.; O'Neal, D. O.; Yilmaz, M.; Selam, S. O.

2018-04-01

We present the surface maps of two eclipsing binary systems KIC11560447 and KIC8868650, using the Kepler light curves covering approximately 4 years. We use the code DoTS, which is based on maximum entropy method in order to reconstruct the surface maps. We also perform numerical tests of DoTS to check the ability of the code in terms of tracking phase migration of spot clusters. The resulting latitudinally averaged maps of KIC11560447 show that spots drift towards increasing orbital longitudes, while the overall behaviour of spots on KIC8868650 drifts towards decreasing latitudes.

Development of DNA-based Identification methods to track the ...

EPA Pesticide Factsheets

The ability to track the identity and abundance of larval fish, which are ubiquitous during spawning season, may lead to a greater understanding of fish species distributions in Great Lakes nearshore areas including early-detection of invasive fish species before they become established. However, larval fish are notoriously hard to identify using traditional morphological techniques. While DNA-based identification methods could increase the ability of aquatic resource managers to determine larval fish composition, use of these methods in aquatic surveys is still uncommon and presents many challenges. In response to this need, we have been working with the U. S. Fish and Wildlife Service to develop field and laboratory methods to facilitate the identification of larval fish using DNA-meta-barcoding. In 2012, we initiated a pilot-project to develop a workflow for conducting DNA-based identification, and compared the species composition at sites within the St. Louis River Estuary of Lake Superior using traditional identification versus DNA meta-barcoding. In 2013, we extended this research to conduct DNA-identification of fish larvae collected from multiple nearshore areas of the Great Lakes by the USFWS. The species composition of larval fish generally mirrored that of fish species known from the same areas, but was influenced by the timing and intensity of sampling. Results indicate that DNA-based identification needs only very low levels of biomass to detect pre

Relationship between axenic growth of Dictyostelium discoideum strains and their track morphology on substrates coated with gold particles

PubMed Central

1983-01-01

Amoebae of Dictyostelium discoideum produce tracks with two distinct morphologies on gold-coated coverslips. The wild-type strain and other strains that feed only by phagocytosis produced indistinct, fuzzy tracks, whereas mutants capable of axenic growth produced clear, sharp tracks. The sharp track morphology was found to be a recessive phenotype that segregates with axenicity and probably requires a previously unidentified axenic mutation. Axenic and nonaxenic strains also differed in their ability to pinocytose. When the two types of cells were shifted from bacterial growth plates to nutrient media, within 24 h the axenic strain established a rapid rate of pinocytosis, approximately 100-fold higher than the low rate detectable for the nonaxenic strain. However, track formation did not appear to be directly related to endocytosis. Electron microscopic examination of cells during track formation showed that both axenic and nonaxenic strains accumulated gold particles on their surfaces, but neither strain internalized the gold to any significant degree. Observation of living cells revealed that axenic strains collected all particles that they contacted, whereas wild-type strains left many particles undisturbed. The size of the gold particle clusters discarded by the cells also contributed to track morphology. PMID:6619183

Indirect learning control for nonlinear dynamical systems

NASA Technical Reports Server (NTRS)

Ryu, Yeong Soon; Longman, Richard W.

1993-01-01

In a previous paper, learning control algorithms were developed based on adaptive control ideas for linear time variant systems. The learning control methods were shown to have certain advantages over their adaptive control counterparts, such as the ability to produce zero tracking error in time varying systems, and the ability to eliminate repetitive disturbances. In recent years, certain adaptive control algorithms have been developed for multi-body dynamic systems such as robots, with global guaranteed convergence to zero tracking error for the nonlinear system euations. In this paper we study the relationship between such adaptive control methods designed for this specific class of nonlinear systems, and the learning control problem for such systems, seeking to converge to zero tracking error in following a specific command repeatedly, starting from the same initial conditions each time. The extension of these methods from the adaptive control problem to the learning control problem is seen to be trivial. The advantages and disadvantages of using learning control based on such adaptive control concepts for nonlinear systems, and the use of other currently available learning control algorithms are discussed.

Task Values and Ability Beliefs as Predictors of High School Literacy Choices: A Developmental Analysis

ERIC Educational Resources Information Center

Durik, Amanda M.; Vida, Mina; Eccles, Jacquelynne S.

2005-01-01

This study examines how competence beliefs and task values predict high school achievement choices related to literacy. Students' task beliefs (self-concept of ability, intrinsic value, and importance) about reading in the 4th grade and English in the 10th grade were tracked over time. Task beliefs, school performance, and gender were used to…

Route-Learning Strategies in Typical and Atypical Development; Eye Tracking Reveals Atypical Landmark Selection in Williams Syndrome

ERIC Educational Resources Information Center

Farran, E. K.; Formby, S.; Daniyal, F.; Holmes, T.; Van Herwegen, J.

2016-01-01

Background: Successful navigation is crucial to everyday life. Individuals with Williams syndrome (WS) have impaired spatial abilities. This includes a deficit in spatial navigation abilities such as learning the route from A to B. To-date, to determine whether participants attend to landmarks when learning a route, landmark recall tasks have been…

Investigating the Impact of Cognitive Style on Multimedia Learners' Understanding and Visual Search Patterns: An Eye-Tracking Approach

ERIC Educational Resources Information Center

Liu, Han-Chin

2018-01-01

Multimedia students' dependence on information from the outside world can have an impact on their ability to identify and locate information from multiple resources in learning environments and thereby affect the construction of mental models. Field dependence-independence has been used to assess the ability to extract essential information from…

Effects of Age and Schooling on Intellectual Performance: Estimates Obtained from Analysis of Continuous Variation in Age and Length of Schooling

ERIC Educational Resources Information Center

Cliffordson, Christina; Gustafsson, Jan-Eric

2008-01-01

The effects of age and schooling on different aspects of intellectual performance, taking track of study into account, are investigated. The analyses were based on military enlistment test scores, obtained by 48,269 males, measuring Fluid ability (Gf), Crystallized intelligence (Gc), and General visualization (Gv) ability. A regression method,…

Defense Additive Manufacturing: DOD Needs to Systematically Track Department-wide 3D Printing Efforts

DTIC Science & Technology

2015-10-01

Clip Additively Manufactured • The Navy installed a 3D printer aboard the USS Essex to demonstrate the ability to additively develop and produce...desired result and vision to have the capability on the fleet. These officials stated that the Navy plans to install 3D printers on two additional...DEFENSE ADDITIVE MANUFACTURING DOD Needs to Systematically Track Department-wide 3D Printing Efforts Report to

Human adaptations for the visual assessment of strength and fighting ability from the body and face

PubMed Central

Sell, Aaron; Cosmides, Leda; Tooby, John; Sznycer, Daniel; von Rueden, Christopher; Gurven, Michael

2008-01-01

Selection in species with aggressive social interactions favours the evolution of cognitive mechanisms for assessing physical formidability (fighting ability or resource-holding potential). The ability to accurately assess formidability in conspecifics has been documented in a number of non-human species, but has not been demonstrated in humans. Here, we report tests supporting the hypothesis that the human cognitive architecture includes mechanisms that assess fighting ability—mechanisms that focus on correlates of upper-body strength. Across diverse samples of targets that included US college students, Bolivian horticulturalists and Andean pastoralists, subjects in the US were able to accurately estimate the physical strength of male targets from photos of their bodies and faces. Hierarchical linear modelling shows that subjects were extracting cues of strength that were largely independent of height, weight and age, and that corresponded most strongly to objective measures of upper-body strength—even when the face was all that was available for inspection. Estimates of women's strength were less accurate, but still significant. These studies are the first empirical demonstration that, for humans, judgements of strength and judgements of fighting ability not only track each other, but accurately track actual upper-body strength. PMID:18945661

Detection limit of a VCO based detection chain dedicated to particles recognition and tracking

NASA Astrophysics Data System (ADS)

Coulié, K.; Rahajandraibe, W.; Aziza, H.; Micolau, G.; Vauché, R.

2018-01-01

A particle detection chain based on CMOS-SOI VCO circuit is presented. The solution is used for the recognition and the tracking of a given particle at circuit level. TCAD simulation of the detector has been performed on a 3×3 matrix of diodes based detector for particles recognition and tracking. The current response of the detector has been used for a case study in order to determine the ability of the chain to recognize an alpha particle crossing a 3×3 detection cell. The detection limit of the proposed solution is investigated and discussed in this paper.

Innate immune response development in nestling tree swallows

USGS Publications Warehouse

Stambaugh, T.; Houdek, B.J.; Lombardo, M.P.; Thorpe, P.A.; Caldwell, Hahn D.

2011-01-01

We tracked the development of innate immunity in nestling Tree Swallows (Tachycineta bicolor) and compared it to that of adults using blood drawn from nestlings during days 6, 12, and 18 of the ???20-day nestling period and from adults. Innate immunity was characterized using an in vitro assay of the ability of whole blood to kill Escherichia coli. The ability of whole blood to kill E. coli increased as nestlings matured. Neither this component of innate immunity nor right wing chord length on day18 were as developed as in adults indicating that development of the innate immune system and growth both continued after fledging. Narrow sense heritability analyses suggest that females with strong immune responses produced nestlings with strong immune responses. These data suggest nestling Tree Swallows allocated sufficient energy to support rapid growth to enable fledging by day 18, but that further development of innate immunity occurred post-fledging. ?? 2011 by the Wilson Ornithological Society.

Effects of state managed care patient protection laws on physician satisfaction.

PubMed

Sloan, Frank A; Rattliff, John R; Hall, Mark A

2007-10-01

Physician dissatisfaction often drives public policy, and is associated with lower quality of care and disruption of treatment relationships. Physicians expressed strong dissatisfaction with managed care, leading to enactment of patient protection laws. By 2001, almost all states enacted laws to curb alleged abuses of managed care organizations. To date, no studies have examined whether such laws improved physician satisfaction. This article examines whether enactment of these laws improved physician satisfaction, using responses to the Physician Survey component of the Community Tracking Study (CTS), supplemented with data on state statutes/regulations. Career satisfaction increased for both primary care physicians (PCPs) and specialists following enactment of such laws; improvements were limited to early-adopting states. Enactment was associated with improvements in early-adopting states for specialists but not for PCPs on: ability to provide high quality care, clinical freedom, and ability to make clinical decisions in patients' interests without sacrificing physician income.

Measuring Animal Age with DNA Methylation: From Humans to Wild Animals.

PubMed

De Paoli-Iseppi, Ricardo; Deagle, Bruce E; McMahon, Clive R; Hindell, Mark A; Dickinson, Joanne L; Jarman, Simon N

2017-01-01

DNA methylation (DNAm) is a key mechanism for regulating gene expression in animals and levels are known to change with age. Recent studies have used DNAm changes as a biomarker to estimate chronological age in humans and these techniques are now also being applied to domestic and wild animals. Animal age is widely used to track ongoing changes in ecosystems, however chronological age information is often unavailable for wild animals. An ability to estimate age would lead to improved monitoring of (i) population trends and status and (ii) demographic properties such as age structure and reproductive performance. Recent studies have revealed new examples of DNAm age association in several new species increasing the potential for developing DNAm age biomarkers for a broad range of wild animals. Emerging technologies for measuring DNAm will also enhance our ability to study age-related DNAm changes and to develop new molecular age biomarkers.

Investigation of control law reconfigurations to accommodate a control element failure on a commercial airplane

NASA Technical Reports Server (NTRS)

Ostroff, A. J.; Hueschen, R. M.

1984-01-01

The ability of a pilot to reconfigure the control surfaces on an airplane after a failure, allowing the airplane to recover to a safe condition, becomes more difficult with increasing airplane complexity. Techniques are needed to stabilize and control the airplane immediately after a failure, allowing the pilot more time to make longer range decisions. This paper presents a baseline design of a discrete multivariable control law using four controls for the longitudinal channel of a B-737. Non-reconfigured and reconfigured control laws are then evaluated, both analytically and by means of a digital airplane simulation, for three individual control element failures (stabilizer, elevator, spoilers). The simulation results are used to evaluate the effectiveness of the control reconfiguration on tracking ability during the approach and landing phase of flight with severe windshear and turbulence disturbing the airplane dynamics.

Polar Mesospheric Clouds (PMCs) Observed by the Ozone Monitoring Instrument (OMI) on Aura

NASA Technical Reports Server (NTRS)

DeLand, Matthew T.; Shettle, Eric P.; Levelt, Pieternel F.; Kowalewski, Matthew G.

2010-01-01

Backscattered ultraviolet (BUV) instruments designed for measuring stratospheric ozone profiles have proven to be robust tools for observing polar mesospheric clouds (PMCs). These measurements are available for more than 30 years, and have been used to demonstrate the existence of long-term variations in PMC occurrence frequency and brightness. The Ozone Monitoring Instrument (OMI) on the EOS Aura satellite provides new and improved capabilities for PMC characterization. OMI uses smaller pixels than previous BUV instruments, which increases its ability to identify PMCs and discern more spatial structure, and its wide cross-track viewing swath provides full polar coverage up to 90 latitude every day in both hemispheres. This cross-track coverage allows the evolution of PMC regions to be followed over several consecutive orbits. Localized PMC variations determined from OMI measurements are consistent with coincident SBUV/2 measurements. Nine seasons of PMC observations from OMI are now available, and clearly demonstrate the advantages of these measurements for PMC analysis.

Organ motion due to respiration: the state of the art and applications in interventional radiology and radiation oncology

NASA Astrophysics Data System (ADS)

Cleary, Kevin R.; Mulcahy, Maureen; Piyasena, Rohan; Zhou, Tong; Dieterich, Sonja; Xu, Sheng; Banovac, Filip; Wong, Kenneth H.

2005-04-01

Tracking organ motion due to respiration is important for precision treatments in interventional radiology and radiation oncology, among other areas. In interventional radiology, the ability to track and compensate for organ motion could lead to more precise biopsies for applications such as lung cancer screening. In radiation oncology, image-guided treatment of tumors is becoming technically possible, and the management of organ motion then becomes a major issue. This paper will review the state-of-the-art in respiratory motion and present two related clinical applications. Respiratory motion is an important topic for future work in image-guided surgery and medical robotics. Issues include how organs move due to respiration, how much they move, how the motion can be compensated for, and what clinical applications can benefit from respiratory motion compensation. Technology that can be applied for this purpose is now becoming available, and as that technology evolves, the subject will become an increasingly interesting and clinically valuable topic of research.

Achieving climate connectivity in a fragmented landscape

PubMed Central

Lawler, Joshua J.; McRae, Brad H.; Nuñez, Tristan A.; Theobald, David M.

2016-01-01

The contiguous United States contains a disconnected patchwork of natural lands. This fragmentation by human activities limits species’ ability to track suitable climates as they rapidly shift. However, most models that project species movement needs have not examined where fragmentation will limit those movements. Here, we quantify climate connectivity, the capacity of landscape configuration to allow species movement in the face of dynamically shifting climate. Using this metric, we assess to what extent habitat fragmentation will limit species movements in response to climate change. We then evaluate how creating corridors to promote climate connectivity could potentially mitigate these restrictions, and we assess where strategies to increase connectivity will be most beneficial. By analyzing fragmentation patterns across the contiguous United States, we demonstrate that only 41% of natural land area retains enough connectivity to allow plants and animals to maintain climatic parity as the climate warms. In the eastern United States, less than 2% of natural area is sufficiently connected. Introducing corridors to facilitate movement through human-dominated regions increases the percentage of climatically connected natural area to 65%, with the most impactful gains in low-elevation regions, particularly in the southeastern United States. These climate connectivity analyses allow ecologists and conservation practitioners to determine the most effective regions for increasing connectivity. More importantly, our findings demonstrate that increasing climate connectivity is critical for allowing species to track rapidly changing climates, reconfiguring habitats to promote access to suitable climates. PMID:27298349

Achieving climate connectivity in a fragmented landscape.

PubMed

McGuire, Jenny L; Lawler, Joshua J; McRae, Brad H; Nuñez, Tristan A; Theobald, David M

2016-06-28

The contiguous United States contains a disconnected patchwork of natural lands. This fragmentation by human activities limits species' ability to track suitable climates as they rapidly shift. However, most models that project species movement needs have not examined where fragmentation will limit those movements. Here, we quantify climate connectivity, the capacity of landscape configuration to allow species movement in the face of dynamically shifting climate. Using this metric, we assess to what extent habitat fragmentation will limit species movements in response to climate change. We then evaluate how creating corridors to promote climate connectivity could potentially mitigate these restrictions, and we assess where strategies to increase connectivity will be most beneficial. By analyzing fragmentation patterns across the contiguous United States, we demonstrate that only 41% of natural land area retains enough connectivity to allow plants and animals to maintain climatic parity as the climate warms. In the eastern United States, less than 2% of natural area is sufficiently connected. Introducing corridors to facilitate movement through human-dominated regions increases the percentage of climatically connected natural area to 65%, with the most impactful gains in low-elevation regions, particularly in the southeastern United States. These climate connectivity analyses allow ecologists and conservation practitioners to determine the most effective regions for increasing connectivity. More importantly, our findings demonstrate that increasing climate connectivity is critical for allowing species to track rapidly changing climates, reconfiguring habitats to promote access to suitable climates.

A Finite-Element Method Model of Soft Tissue Response to Impulsive Acoustic Radiation Force

PubMed Central

Palmeri, Mark L.; Sharma, Amy C.; Bouchard, Richard R.; Nightingale, Roger W.; Nightingale, Kathryn R

2010-01-01

Several groups are studying acoustic radiation force and its ability to image the mechanical properties of tissue. Acoustic radiation force impulse (ARFI) imaging is one modality using standard diagnostic ultrasound scanners to generate localized, impulsive, acoustic radiation forces in tissue. The dynamic response of tissue is measured via conventional ultrasonic speckle-tracking methods and provides information about the mechanical properties of tissue. A finite-element method (FEM) model has been developed that simulates the dynamic response of tissues, with and without spherical inclusions, to an impulsive acoustic radiation force excitation from a linear array transducer. These FEM models were validated with calibrated phantoms. Shear wave speed, and therefore elasticity, dictates tissue relaxation following ARFI excitation, but Poisson’s ratio and density do not significantly alter tissue relaxation rates. Increased acoustic attenuation in tissue increases the relative amount of tissue displacement in the near field compared with the focal depth, but relaxation rates are not altered. Applications of this model include improving image quality, and distilling material and structural information from tissue’s dynamic response to ARFI excitation. Future work on these models includes incorporation of viscous material properties and modeling the ultrasonic tracking of displaced scatterers. PMID:16382621

Weighing Scale-Based Pulse Transit Time is a Superior Marker of Blood Pressure than Conventional Pulse Arrival Time

NASA Astrophysics Data System (ADS)

Martin, Stephanie L.-O.; Carek, Andrew M.; Kim, Chang-Sei; Ashouri, Hazar; Inan, Omer T.; Hahn, Jin-Oh; Mukkamala, Ramakrishna

2016-12-01

Pulse transit time (PTT) is being widely pursued for cuff-less blood pressure (BP) monitoring. Most efforts have employed the time delay between ECG and finger photoplethysmography (PPG) waveforms as a convenient surrogate of PTT. However, these conventional pulse arrival time (PAT) measurements include the pre-ejection period (PEP) and the time delay through small, muscular arteries and may thus be an unreliable marker of BP. We assessed a bathroom weighing scale-like system for convenient measurement of ballistocardiography and foot PPG waveforms - and thus PTT through larger, more elastic arteries - in terms of its ability to improve tracking of BP in individual subjects. We measured “scale PTT”, conventional PAT, and cuff BP in humans during interventions that increased BP but changed PEP and smooth muscle contraction differently. Scale PTT tracked the diastolic BP changes well, with correlation coefficient of -0.80 ± 0.02 (mean ± SE) and root-mean-squared-error of 7.6 ± 0.5 mmHg after a best-case calibration. Conventional PAT was significantly inferior in tracking these changes, with correlation coefficient of -0.60 ± 0.04 and root-mean-squared-error of 14.6 ± 1.5 mmHg (p < 0.05). Scale PTT also tracked the systolic BP changes better than conventional PAT but not to an acceptable level. With further development, scale PTT may permit reliable, convenient measurement of BP.

Weighing Scale-Based Pulse Transit Time is a Superior Marker of Blood Pressure than Conventional Pulse Arrival Time.

PubMed

Martin, Stephanie L-O; Carek, Andrew M; Kim, Chang-Sei; Ashouri, Hazar; Inan, Omer T; Hahn, Jin-Oh; Mukkamala, Ramakrishna

2016-12-15

Pulse transit time (PTT) is being widely pursued for cuff-less blood pressure (BP) monitoring. Most efforts have employed the time delay between ECG and finger photoplethysmography (PPG) waveforms as a convenient surrogate of PTT. However, these conventional pulse arrival time (PAT) measurements include the pre-ejection period (PEP) and the time delay through small, muscular arteries and may thus be an unreliable marker of BP. We assessed a bathroom weighing scale-like system for convenient measurement of ballistocardiography and foot PPG waveforms - and thus PTT through larger, more elastic arteries - in terms of its ability to improve tracking of BP in individual subjects. We measured "scale PTT", conventional PAT, and cuff BP in humans during interventions that increased BP but changed PEP and smooth muscle contraction differently. Scale PTT tracked the diastolic BP changes well, with correlation coefficient of -0.80 ± 0.02 (mean ± SE) and root-mean-squared-error of 7.6 ± 0.5 mmHg after a best-case calibration. Conventional PAT was significantly inferior in tracking these changes, with correlation coefficient of -0.60 ± 0.04 and root-mean-squared-error of 14.6 ± 1.5 mmHg (p < 0.05). Scale PTT also tracked the systolic BP changes better than conventional PAT but not to an acceptable level. With further development, scale PTT may permit reliable, convenient measurement of BP.

Image sequence analysis workstation for multipoint motion analysis

NASA Astrophysics Data System (ADS)

Mostafavi, Hassan

1990-08-01

This paper describes an application-specific engineering workstation designed and developed to analyze motion of objects from video sequences. The system combines the software and hardware environment of a modem graphic-oriented workstation with the digital image acquisition, processing and display techniques. In addition to automation and Increase In throughput of data reduction tasks, the objective of the system Is to provide less invasive methods of measurement by offering the ability to track objects that are more complex than reflective markers. Grey level Image processing and spatial/temporal adaptation of the processing parameters is used for location and tracking of more complex features of objects under uncontrolled lighting and background conditions. The applications of such an automated and noninvasive measurement tool include analysis of the trajectory and attitude of rigid bodies such as human limbs, robots, aircraft in flight, etc. The system's key features are: 1) Acquisition and storage of Image sequences by digitizing and storing real-time video; 2) computer-controlled movie loop playback, freeze frame display, and digital Image enhancement; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored Image sequence; 4) model-based estimation and tracking of the six degrees of freedom of a rigid body: 5) field-of-view and spatial calibration: 6) Image sequence and measurement data base management; and 7) offline analysis software for trajectory plotting and statistical analysis.

Advertising strategies to increase public knowledge of the warning signs of stroke.

PubMed

Silver, Frank L; Rubini, Frank; Black, Diane; Hodgson, Corinne S

2003-08-01

Public awareness of the warning signs of stroke is important. As part of an educational campaign using mass media, the Heart and Stroke Foundation of Ontario conducted public opinion polling in 4 communities to track the level of awareness of the warning signs of stroke and to determine the impact of different media strategies. Telephone surveys were conducted among members of the general public in 1 control and 3 test communities before and after mass media campaigns. The main outcome measure used to determine effectiveness of the campaigns was the ability to name > or =2 warning signs of stroke. In communities exposed to television advertising, ability to name the warning signs of stroke increased significantly. There was no significant change in the community receiving print (newspaper) advertising, and the control community experienced a decrease. Television increased the knowledge of both men and women and of people with less than a secondary school education but not of those > or =65 years of age. Intermittent, low-level television advertising was as effective as continuous, high-level television advertising. Results of this survey can be used to guide mass media-buying strategies for public health education.

Career Development Support in Pediatric Critical Care Medicine: A National Survey of Fellows and Junior Faculty

PubMed Central

Cifra, Christina L.; Balikai, Shilpa S.; Murtha, Tanya D.; Hsu, Benson; Riley, Carley L.

2016-01-01

Objective To determine the perceptions of current pediatric critical care medicine (PCCM) fellows and junior faculty regarding the extent and quality of career development support received during fellowship training. Design Web-based cross-sectional survey open from September to November 2015. Setting Accreditation Council for Graduate Medical Education (ACGME)-accredited PCCM fellowship programs. Participants PCCM fellows (2nd year or higher) and junior faculty (within 5 years of completing a PCCM fellowship program). Interventions None. Measurements and Main Results There were 129 respondents to the survey, representing 63% of ACGME-accredited PCCM fellowship programs. Respondents were evenly divided between fellows and junior faculty. Nearly half (49%) of respondents reported that their PCCM fellowship program provided a formal career development curriculum. Ideal career tracks chosen included academic clinician educator (64%), physician-scientist (27%), community-based (non-academic) clinician (11%), and administrator (11%). There was a disparity in focused career development support provided by programs, with a minority providing good support for those pursuing a community-based clinician track (32%) or administrator track (16%). Only 43% of fellows perceived that they have a good chance of obtaining their ideal PCCM position, with the most common perceived barrier being increased competition for limited job opportunities. Most respondents expressed interest in a program specific to PCCM career development that is sponsored by a national professional organization. Conclusions Most PCCM fellows and junior faculty reported good to excellent career development support during fellowship. However, important gaps remain, particularly for those pursuing community-based (non-academic) and administrative tracks. Fellows were uncertain regarding future PCCM employment and their ability to pursue ideal career tracks. There may be a role for professional organizations to provide additional resources for career development in PCCM. PMID:28198755

The tendency to sign-track predicts cue-induced reinstatement during nicotine self-administration, and is enhanced by nicotine but not ethanol

PubMed Central

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

Classification of team sport activities using a single wearable tracking device.

PubMed

Wundersitz, Daniel W T; Josman, Casey; Gupta, Ritu; Netto, Kevin J; Gastin, Paul B; Robertson, Sam

2015-11-26

Wearable tracking devices incorporating accelerometers and gyroscopes are increasingly being used for activity analysis in sports. However, minimal research exists relating to their ability to classify common activities. The purpose of this study was to determine whether data obtained from a single wearable tracking device can be used to classify team sport-related activities. Seventy-six non-elite sporting participants were tested during a simulated team sport circuit (involving stationary, walking, jogging, running, changing direction, counter-movement jumping, jumping for distance and tackling activities) in a laboratory setting. A MinimaxX S4 wearable tracking device was worn below the neck, in-line and dorsal to the first to fifth thoracic vertebrae of the spine, with tri-axial accelerometer and gyroscope data collected at 100Hz. Multiple time domain, frequency domain and custom features were extracted from each sensor using 0.5, 1.0, and 1.5s movement capture durations. Features were further screened using a combination of ANOVA and Lasso methods. Relevant features were used to classify the eight activities performed using the Random Forest (RF), Support Vector Machine (SVM) and Logistic Model Tree (LMT) algorithms. The LMT (79-92% classification accuracy) outperformed RF (32-43%) and SVM algorithms (27-40%), obtaining strongest performance using the full model (accelerometer and gyroscope inputs). Processing time can be reduced through feature selection methods (range 1.5-30.2%), however a trade-off exists between classification accuracy and processing time. Movement capture duration also had little impact on classification accuracy or processing time. In sporting scenarios where wearable tracking devices are employed, it is both possible and feasible to accurately classify team sport-related activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

The tendency to sign-track predicts cue-induced reinstatement during nicotine self-administration, and is enhanced by nicotine but not ethanol.

PubMed

Versaggi, Cassandra L; King, Christopher P; Meyer, Paul J

2016-08-01

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. 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. 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. 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. 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.

Land-Use Impacts on the Terrestrial Carbon Cycle: An Integrative Tool for Resource Assessment and Planning

NASA Astrophysics Data System (ADS)

Sleeter, B. M.; Liu, J.; Zhu, Z.; Hawbaker, T. J.

2014-12-01

Human land use and natural processes contribute to the ability of ecosystems to store and sequester carbon and offset greenhouse gas emissions. Changes in land use (e.g. agricultural cultivation, timber harvest, urban development, and other land management strategies) and natural processes (e.g. climate, wildfire, disease, storm, and insect outbreak) drive the dynamics of ecosystem carbon pools. These carbon dynamics operate at different spatial and temporal scales, making it challenging to track the changes in a single integrative framework. Landowners, managers, and policy makers require data, information, and tools on the relative contributions of these drivers of ecosystem carbon stocks and fluxes in order to evaluate alternative policies and management strategies designed to increase carbon storage and sequestration. In this paper we explore preliminary results from efforts to simulate changes in ecosystem carbon at ecoregional scales, resulting from anthropogenic land use, wildfire, natural vegetation change, and climate variability under a range of future conditions coherent with a range of global change scenarios. Simulations track the fate of carbon across several pools, including living biomass, deadwood, litter, soil, and wood products. Carbon fluxes are estimated based on simulations from the Integrated Biosphere Simulator model (IBIS). Downscaled land-use projections from the Special Report on Emission Scenarios and Representative Concentration Pathways drive changes in land use, along with extrapolations based on local-scale data. We discuss the sensitivity of the model to individual drivers, and the overall uncertainty associated with the wide range of scenario projections, as well as explore alternative policy and management outcomes and their ability to increase carbon storage in terrestrial ecosystems.

An Ice Track Equipped with Optical Sensors for Determining the Influence of Experimental Conditions on the Sliding Velocity

NASA Astrophysics Data System (ADS)

Lungevics, J.; Jansons, E.; Gross, K. A.

2018-02-01

The ability to slide on ice has previously focused on the measurement of friction coefficient rather than the actual sliding velocity that is affected by it. The performance can only be directly measured by the sliding velocity, and therefore the objective was to design and setup a facility to measure velo-city, and determine how experimental conditions affect it. Optical sensors were placed on an angled ice track to provide sliding velocity measurements along three sections and the velocity for the total sliding distance. Experimental conditions included the surface roughness, ambient temperature and load. The effect of roughness was best reported with a Criterion of Contact that showed a similar sliding velocity for metal blocks abraded with sand paper smoother than 600 grit. Searching for the effect of temperature, the highest sliding velocity coincided with the previously reported lowest coefficient of ice friction. Load showed the greatest velocity increase at temperatures closer to the ice melting point suggesting that in such conditions metal block overcame friction forces more easily than in solid friction. Further research needs to be conducted on a longer ice track, with larger metal surfaces, heavier loads and higher velocities to determine how laboratory experiments can predict real-life situations.

Observations of the structure and evolution of surface and flight-level wind asymmetries in Hurricane Rita (2005)

NASA Astrophysics Data System (ADS)

Rogers, Robert; Uhlhorn, Eric

2008-11-01

Knowledge of the magnitude and distribution of surface winds, including the structure of azimuthal asymmetries in the wind field, are important factors for tropical cyclone forecasting. With its ability to remotely measure surface wind speeds, the stepped frequency microwave radiometer (SFMR) has assumed a prominent role for the operational tropical cyclone forecasting community. An example of this instrument's utility is presented here, where concurrent measurements of aircraft flight-level and SFMR surface winds are used to document the wind field evolution over three days in Hurricane Rita (2005). The amplitude and azimuthal location (phase) of the wavenumber-1 asymmetry in the storm-relative winds varied at both levels over time. The peak was found to the right of storm track at both levels on the first day. By the third day, the peak in flight-level storm-relative winds remained to the right of storm track, but it shifted to left of storm track at the surface, resulting in a 60-degree shift between the surface and flight-level and azimuthal variations in the ratio of surface to flight-level winds. The asymmetric differences between the surface and flight-level maximum wind radii also varied, indicating a vortex whose tilt was increasing.

Study on rejection characteristic of current loop to the base disturbance of optical communication system

NASA Astrophysics Data System (ADS)

Mao, Yao; Deng, Chao; Liu, Qiong; Cao, Zheng

2016-10-01

As laser has narrow transmitting beam and small divergence angle, the LOS (Line of Sight) stabilization of optical communication system is a primary precondition of laser communication links. Compound axis control is usually adopted in LOS stabilization of optical communication system, in which coarse tracking and fine tracking are included. Rejection against high frequency disturbance mainly depends on fine tracking LOS stabilization platform. Limited by different factors such as mechanical characteristic of the stabilization platform and bandwidth/noise of the sensor, the control bandwidth of LOS stabilization platform is restricted so that effective rejection of high frequency disturbance cannot be achieved as it mainly depends on the isolation characteristic of the platform itself. It is proposed by this paper that current loop may reject the effect of back-EMF. By adopting the method of electric control, high frequency isolation characteristic of the platform can be improved. The improvement effect is similar to increasing passive vibration reduction devices. Adopting the double closed loop control structure of velocity and current with the combining of the rejection effect of back-EMF caused by current loop is equivalent to reducing back-EMF coefficient, which can enhance the isolation ability of the LOS stabilization platform to high frequency disturbance.

Naval Survivability and Susceptibility Reduction Study-Surface Ship

DTIC Science & Technology

2012-09-01

the ship, causing damage. There are four properties affecting the susceptibility of a ship. The first property is the ease at which the ship can be...will affect how easily she can be detected. The second property is the ease at which the ship can be effective tracked, identified and classified by...being tracked by the active sensor after the she had been detected (PT|D). The third property is the ability to avoid being targeted. Again this is

Enhancement of ELDA Tracker Based on CNN Features and Adaptive Model Update.

PubMed

Gao, Changxin; Shi, Huizhang; Yu, Jin-Gang; Sang, Nong

2016-04-15

Appearance representation and the observation model are the most important components in designing a robust visual tracking algorithm for video-based sensors. Additionally, the exemplar-based linear discriminant analysis (ELDA) model has shown good performance in object tracking. Based on that, we improve the ELDA tracking algorithm by deep convolutional neural network (CNN) features and adaptive model update. Deep CNN features have been successfully used in various computer vision tasks. Extracting CNN features on all of the candidate windows is time consuming. To address this problem, a two-step CNN feature extraction method is proposed by separately computing convolutional layers and fully-connected layers. Due to the strong discriminative ability of CNN features and the exemplar-based model, we update both object and background models to improve their adaptivity and to deal with the tradeoff between discriminative ability and adaptivity. An object updating method is proposed to select the "good" models (detectors), which are quite discriminative and uncorrelated to other selected models. Meanwhile, we build the background model as a Gaussian mixture model (GMM) to adapt to complex scenes, which is initialized offline and updated online. The proposed tracker is evaluated on a benchmark dataset of 50 video sequences with various challenges. It achieves the best overall performance among the compared state-of-the-art trackers, which demonstrates the effectiveness and robustness of our tracking algorithm.

Enhancement of ELDA Tracker Based on CNN Features and Adaptive Model Update

PubMed Central

Gao, Changxin; Shi, Huizhang; Yu, Jin-Gang; Sang, Nong

2016-01-01

Appearance representation and the observation model are the most important components in designing a robust visual tracking algorithm for video-based sensors. Additionally, the exemplar-based linear discriminant analysis (ELDA) model has shown good performance in object tracking. Based on that, we improve the ELDA tracking algorithm by deep convolutional neural network (CNN) features and adaptive model update. Deep CNN features have been successfully used in various computer vision tasks. Extracting CNN features on all of the candidate windows is time consuming. To address this problem, a two-step CNN feature extraction method is proposed by separately computing convolutional layers and fully-connected layers. Due to the strong discriminative ability of CNN features and the exemplar-based model, we update both object and background models to improve their adaptivity and to deal with the tradeoff between discriminative ability and adaptivity. An object updating method is proposed to select the “good” models (detectors), which are quite discriminative and uncorrelated to other selected models. Meanwhile, we build the background model as a Gaussian mixture model (GMM) to adapt to complex scenes, which is initialized offline and updated online. The proposed tracker is evaluated on a benchmark dataset of 50 video sequences with various challenges. It achieves the best overall performance among the compared state-of-the-art trackers, which demonstrates the effectiveness and robustness of our tracking algorithm. PMID:27092505

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, W; Merrick, G; Kurko, B

Purpose: To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods: Three Calypso transponders were implanted into two prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data was acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data was acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from themore » phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was < 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusion: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible.« less

Short-term influence of tank tracks on vegetation and microphytic crusts in shrubsteppe habitat

USGS Publications Warehouse

Watts, Stephen E.

1998-01-01

Artemisia tridentata Nutt.) habitat within the Idaho Army National Guard Orchard Training Area in southwestern Idaho. The purpose of this study was to determine the short-term (1a??2 years) influence of tank tracks on vegetation and microphytic crusts in shrubsteppe habitat. The two types of tank tracks studied were divots (area where one track has been stopped or slowed to make a sharp turn) and straight-line tracks. Divots generally had a stronger influence on vegetation and microphytic crusts than did straight-line tracks. Tank tracks increased cover of bare ground, litter, and exotic annuals, and reduced cover of vegetation, perennial native grasses, sagebrush, and microphytic crusts. Increased bare ground and reduced cover of vegetation and microphytic crusts caused by tank tracks increase the potential for soil erosion and may reduce ecosystem productivity. Reduced sagebrush cover caused by tank tracks may reduce habitat quality for rodents. Tank tracks may also facilitate the invasion of exotic annuals into sagebrush habitat, increasing the potential for wildfire and subsequent habitat degradation. Thus, creation of divots and movement through sagebrush habitat by tanks should be minimized.

The Effect of Ability, Achievement, and Number of Plays on Learning from a Simulation Game. Report Number 115.

ERIC Educational Resources Information Center

Edwards, Keith J.

This study examines the effect on learning of repeated plays of the simulation game "Trade and Develop" (T/D). It also examines the effects of students' ability, using a general measure (determined by school tracking procedures) and a specific measure (achievement test in the specific class). The results of the study indicate that, after playing…

Real-Time Tracking of Motor Response Activation and Response Competition in a Stroop Task in Young Children: A Lateralized Readiness Potential Study

ERIC Educational Resources Information Center

Szucs, Denes; Soltesz, Fruzsina; Bryce, Donna; Whitebread, David

2009-01-01

The ability to select an appropriate motor response by resolving competition among alternative responses plays a major role in cognitive performance. fMRI studies suggest that the development of this skill is related to the maturation of the frontal cortex that underlies the improvement of motor inhibition abilities. However, fMRI cannot…

The Benefit of Being a Big Fish in a Big Pond: Contrast and Assimilation Effects on Academic Self-Concept

ERIC Educational Resources Information Center

Preckel, Franzis; Brull, Matthias

2010-01-01

This study investigates the effects of class-average ability (intelligence) and class type (gifted vs. regular) on Math academic self-concept. The sample comprised 722 fifth-grade students (376 female) in a setting of full-time ability grouping at the top track of the German secondary high school system. Students came from 34 different classes at…

Meteorological data-processing package

NASA Technical Reports Server (NTRS)

Billingsly, J. B.; Braken, P. A.

1979-01-01

METPAK, meteorological data-processing package of satellite data used to develop cloud-tracking maps, is given. Data can develop and enhance numerical prediction models for mesoscale phenomena and improve ability to detect and predict storms.

Head-mounted display (HMD) assessment for tracked vehicles

NASA Astrophysics Data System (ADS)

Nicholson, Gail

2011-06-01

Providing the warfighter with Head or Helmet Mounted Displays (HMDs) while in tracked vehicles provides a means to visually maintain access to systems information while in a high vibration environment. The high vibration and unique environment of military tracked and turreted vehicles impact the ability to distinctly see certain information on an HMD, especially small font size or graphics and information that requires long fixation (staring), rather than a brief or peripheral glance. The military and commercial use of HMDs was compiled from market research, market trends, and user feedback. Lessons learned from previous military and commercial use of HMD products were derived to determine the feasibility of HMDs use in the high vibration and the unique environments of tracked vehicles. The results are summarized into factors that determine HMD features which must be specified for successful implementation.

Toward experimental validation of a model for human sensorimotor learning and control in teleoperation

NASA Astrophysics Data System (ADS)

Roth, Eatai; Howell, Darrin; Beckwith, Cydney; Burden, Samuel A.

2017-05-01

Humans, interacting with cyber-physical systems (CPS), formulate beliefs about the system's dynamics. It is natural to expect that human operators, tasked with teleoperation, use these beliefs to control the remote robot. For tracking tasks in the resulting human-cyber-physical system (HCPS), theory suggests that human operators can achieve exponential tracking (in stable systems) without state estimation provided they possess an accurate model of the system's dynamics. This internalized inverse model, however, renders a portion of the system state unobservable to the human operator—the zero dynamics. Prior work shows humans can track through observable linear dynamics, thus we focus on nonlinear dynamics rendered unobservable through tracking control. We propose experiments to assess the human operator's ability to learn and invert such models, and distinguish this behavior from that achieved by pure feedback control.

Digital accumulators in phase and frequency tracking loops

NASA Technical Reports Server (NTRS)

Hinedi, Sami; Statman, Joseph I.

1990-01-01

Results on the effects of digital accumulators in phase and frequency tracking loops are presented. Digital accumulators or summers are used extensively in digital signal processing to perform averaging or to reduce processing rates to acceptable levels. For tracking the Doppler of high-dynamic targets at low carrier-to-noise ratios, it is shown through simulation and experiment that digital accumulators can contribute an additional loss in operating threshold. This loss was not considered in any previous study and needs to be accounted for in performance prediction analysis. Simulation and measurement results are used to characterize the loss due to the digital summers for three different tracking loops: a digital phase-locked loop, a cross-product automatic frequency tracking loop, and an extended Kalman filter. The tracking algorithms are compared with respect to their frequency error performance and their ability to maintain lock during severe maneuvers at various carrier-to-noise ratios. It is shown that failure to account for the effect of accumulators can result in an inaccurate performance prediction, the extent of which depends highly on the algorithm used.

Robust back-stepping output feedback trajectory tracking for quadrotors via extended state observer and sigmoid tracking differentiator

NASA Astrophysics Data System (ADS)

Shao, Xingling; Liu, Jun; Wang, Honglun

2018-05-01

In this paper, a robust back-stepping output feedback trajectory tracking controller is proposed for quadrotors subject to parametric uncertainties and external disturbances. Based on the hierarchical control principle, the quadrotor dynamics is decomposed into translational and rotational subsystems to facilitate the back-stepping control design. With given model information incorporated into observer design, a high-order extended state observer (ESO) that relies only on position measurements is developed to estimate the remaining unmeasurable states and the lumped disturbances in rotational subsystem simultaneously. To overcome the problem of "explosion of complexity" in the back-stepping design, the sigmoid tracking differentiator (STD) is introduced to compute the derivative of virtual control laws. The advantage is that the proposed controller via output-feedback scheme not only can ensure good tracking performance using very limited information of quadrotors, but also has the ability of handling the undesired uncertainties. The stability analysis is established using the Lyapunov theory. Simulation results demonstrate the effectiveness of the proposed control scheme in achieving a guaranteed tracking performance with respect to an 8-shaped reference trajectory.

Understanding GRETINA using angular correlation method

NASA Astrophysics Data System (ADS)

Austin, Madeline

2015-10-01

The ability to trace the path of gamma rays through germanium is not only necessary for taking full advantage of GRETINA but also a promising possibility for homeland security defense against nuclear threats. This research tested the current tracking algorithm using the angular correlation method by comparing results from raw and tracked data to the theoretical model for Co-60. It was found that the current tracking method is unsuccessful in reproducing angular correlation. Variations to the tracking algorithm were made in the FM value, tracking angle, number of angles of separation observed, and window of coincidence in attempt to improve correlation results. From these variations it was observed that having a larger FM improved results, reducing the number of observational angles worsened correlation, and that overall larger tracking angles improved with larger windows of coincidence and vice-verse. Future research would be to refine the angle of measurement for raw data and to explore the possibility of an energy dependence by testing other elements. This work is supported by the United States Department of Energy, Office of Science, under Contract Number DE-AC02-06CH11357

The Publications Tracking and Metrics Program at NOAO: Challenges and Opportunities

NASA Astrophysics Data System (ADS)

Hunt, Sharon

2015-08-01

The National Optical Astronomy Observatory (NOAO) is the U.S. national research and development center for ground-based nighttime astronomy. The NOAO librarian manages the organization’s publications tracking and metrics program, which consists of three components: identifying publications, organizing citation data, and disseminating publications information. We are developing methods to streamline these tasks, better organize our data, provide greater accessibility to publications data, and add value to our services.Our publications tracking process is complex, as we track refereed publications citing data from several sources: NOAO telescopes at two observatory sites, telescopes of consortia in which NOAO participates, the NOAO Science Archive, and NOAO-granted community-access time on non-NOAO telescopes. We also identify and document our scientific staff publications. In addition, several individuals contribute publications data.In the past year, we made several changes in our publications tracking and metrics program. To better organize our data and streamline the creation of reports and metrics, we created a MySQL publications database. When designing this relational database, we considered ease of use, the ability to incorporate data from various sources, efficiency in data inputting and sorting, and potential for growth. We also considered the types of metrics we wished to generate from our publications data based on our target audiences and the messages we wanted to convey. To increase accessibility and dissemination of publications information, we developed a publications section on the library’s website, with citation lists, acknowledgements guidelines, and metrics. We are now developing a searchable online database for our website using PHP.The publications tracking and metrics program has provided many opportunities for the library to market its services and contribute to the organization’s mission. As we make decisions on collecting, organizing, and disseminating publications information and metrics, we add to the visibility of the library, gain professional recognition, and produce a value-added service.

Multiple object, three-dimensional motion tracking using the Xbox Kinect sensor

NASA Astrophysics Data System (ADS)

Rosi, T.; Onorato, P.; Oss, S.

2017-11-01

In this article we discuss the capability of the Xbox Kinect sensor to acquire three-dimensional motion data of multiple objects. Two experiments regarding fundamental features of Newtonian mechanics are performed to test the tracking abilities of our setup. Particular attention is paid to check and visualise the conservation of linear momentum, angular momentum and energy. In both experiments, two objects are tracked while falling in the gravitational field. The obtained data is visualised in a 3D virtual environment to help students understand the physics behind the performed experiments. The proposed experiments were analysed with a group of university students who are aspirant physics and mathematics teachers. Their comments are presented in this paper.

Intelligent system of coordination and control for manufacturing

NASA Astrophysics Data System (ADS)

Ciortea, E. M.

2016-08-01

This paper wants shaping an intelligent system monitoring and control, which leads to optimizing material and information flows of the company. The paper presents a model for tracking and control system using intelligent real. Production system proposed for simulation analysis provides the ability to track and control the process in real time. Using simulation models be understood: the influence of changes in system structure, commands influence on the general condition of the manufacturing process conditions influence the behavior of some system parameters. Practical character consists of tracking and real-time control of the technological process. It is based on modular systems analyzed using mathematical models, graphic-analytical sizing, configuration, optimization and simulation.

TrackMate: An open and extensible platform for single-particle tracking.

PubMed

Tinevez, Jean-Yves; Perry, Nick; Schindelin, Johannes; Hoopes, Genevieve M; Reynolds, Gregory D; Laplantine, Emmanuel; Bednarek, Sebastian Y; Shorte, Spencer L; Eliceiri, Kevin W

2017-02-15

We present TrackMate, an open source Fiji plugin for the automated, semi-automated, and manual tracking of single-particles. It offers a versatile and modular solution that works out of the box for end users, through a simple and intuitive user interface. It is also easily scriptable and adaptable, operating equally well on 1D over time, 2D over time, 3D over time, or other single and multi-channel image variants. TrackMate provides several visualization and analysis tools that aid in assessing the relevance of results. The utility of TrackMate is further enhanced through its ability to be readily customized to meet specific tracking problems. TrackMate is an extensible platform where developers can easily write their own detection, particle linking, visualization or analysis algorithms within the TrackMate environment. This evolving framework provides researchers with the opportunity to quickly develop and optimize new algorithms based on existing TrackMate modules without the need of having to write de novo user interfaces, including visualization, analysis and exporting tools. The current capabilities of TrackMate are presented in the context of three different biological problems. First, we perform Caenorhabditis-elegans lineage analysis to assess how light-induced damage during imaging impairs its early development. Our TrackMate-based lineage analysis indicates the lack of a cell-specific light-sensitive mechanism. Second, we investigate the recruitment of NEMO (NF-κB essential modulator) clusters in fibroblasts after stimulation by the cytokine IL-1 and show that photodamage can generate artifacts in the shape of TrackMate characterized movements that confuse motility analysis. Finally, we validate the use of TrackMate for quantitative lifetime analysis of clathrin-mediated endocytosis in plant cells. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Aquatic Toxic Analysis by Monitoring Fish Behavior Using Computer Vision: A Recent Progress

PubMed Central

Fu, Longwen; Liu, Zuoyi

2018-01-01

Video tracking based biological early warning system achieved a great progress with advanced computer vision and machine learning methods. Ability of video tracking of multiple biological organisms has been largely improved in recent years. Video based behavioral monitoring has become a common tool for acquiring quantified behavioral data for aquatic risk assessment. Investigation of behavioral responses under chemical and environmental stress has been boosted by rapidly developed machine learning and artificial intelligence. In this paper, we introduce the fundamental of video tracking and present the pioneer works in precise tracking of a group of individuals in 2D and 3D space. Technical and practical issues suffered in video tracking are explained. Subsequently, the toxic analysis based on fish behavioral data is summarized. Frequently used computational methods and machine learning are explained with their applications in aquatic toxicity detection and abnormal pattern analysis. Finally, advantages of recent developed deep learning approach in toxic prediction are presented. PMID:29849612

Brain Activation in Primary Motor and Somatosensory Cortices during Motor Imagery Correlates with Motor Imagery Ability in Stroke Patients

PubMed Central

Confalonieri, Linda; Pagnoni, Giuseppe; Barsalou, Lawrence W.; Rajendra, Justin; Eickhoff, Simon B.; Butler, Andrew J.

2012-01-01

Aims. While studies on healthy subjects have shown a partial overlap between the motor execution and motor imagery neural circuits, few have investigated brain activity during motor imagery in stroke patients with hemiparesis. This work is aimed at examining similarities between motor imagery and execution in a group of stroke patients. Materials and Methods. Eleven patients were asked to perform a visuomotor tracking task by either physically or mentally tracking a sine wave force target using their thumb and index finger during fMRI scanning. MIQ-RS questionnaire has been administered. Results and Conclusion. Whole-brain analyses confirmed shared neural substrates between motor imagery and motor execution in bilateral premotor cortex, SMA, and in the contralesional inferior parietal lobule. Additional region of interest-based analyses revealed a negative correlation between kinaesthetic imagery ability and percentage BOLD change in areas 4p and 3a; higher imagery ability was associated with negative and lower percentage BOLD change in primary sensorimotor areas during motor imagery. PMID:23378930

Studying visual attention using the multiple object tracking paradigm: A tutorial review.

PubMed

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.

SCIGN; new Southern California GPS network advances the study of earthquakes

USGS Publications Warehouse

Hudnut, Ken; King, Nancy

2001-01-01

Southern California is a giant jigsaw puzzle, and scientists are now using GPS satellites to track the pieces. These puzzle pieces are continuously moving, slowly straining the faults in between. That strain is then eventually released in earthquakes. The innovative Southern California Integrated GPS Network (SCIGN) tracks the motions of these pieces over most of southern California with unprecedented precision. This new network greatly improves the ability to assess seismic hazards and quickly measure the larger displacements that occur during and immediatelyafter earthquakes.

Dielectric compound parabolic concentrating solar collector with frustrated total internal reflection absorber

NASA Astrophysics Data System (ADS)

Hull, J. R.

Since its introduction, the concept of nonimaging solar concentrators, as exemplified by the compound parabolic concentrator (CPC) design, has greatly enhanced the ability to collect solar energy efficiently in thermal and photovoltaic devices. When used as a primary concentrator, a CPC can provide significant concentration without the complication of a tracking mechanism and its associated maintenance problems. When used as a secondary, a CPC provides higher total concentration, or for a fixed concentration, tolerates greater tracking error in the primary.

An Assessment of the Ability of the U.S. Department of Defense and the Services to Measure and Track Language and Culture Training and Capabilities Among General Purpose Forces

DTIC Science & Technology

2012-01-01

1) • respecting cultural differences (2) • applying appropriate social etiquette (3) • changing behavior to fit the cultural context (5) • verbal...and applying appropriate social etiquette , which are general capabilities that can benefit service members across different job types. In contrast...interview protocols to discuss tracking of LREC training and to solicit informa- tion on how interviewees felt about the relationship between training and

Features of single tracks in coaxial laser cladding of a NIbased self-fluxing alloy

NASA Astrophysics Data System (ADS)

Feldshtein, Eugene; Devojno, Oleg; Kardapolava, Marharyta; Lutsko, Nikolaj

2017-10-01

In the present paper, the influence of coaxial laser cladding conditions on the dimensions, microstructure, phases and microhardness of Ni-based self-fluxing alloy single tracks is studied. The height and width of single tracks depend on the speed and distance of the laser cladding: increasing the nozzle distance from the deposited surface 1.4 times reduces the width of the track 1.2 - 1.3 times and increases its height 1.2 times. The increase of the laser spot speed 3 times reduces the track width 1.2 - 1.4 times and the height in 1.5 - 1.6 times. At the same time, the increase of the laser spot speed 3 times reduces the track width 1.2 - 1.4 times and the height 1.5 - 1.6 times. Regularities in the formation of single tracks microstructure with different cladding conditions are defined, as well as regularity of distribution of elements over the track depth and in the transient zone. The patterns of microhardness distribution over the track depth for different cladding conditions are found.

Impedance hand controllers for increasing efficiency in teleoperations

NASA Technical Reports Server (NTRS)

Carignan, C.; Tarrant, J.

1989-01-01

An impedance hand controller with direct force feedback is examined as an alternative to bilateral force reflection in teleoperations involving force contact. Experimentation revealed an operator preference for direct force feedback which provided a better feel of contact with the environment. The advantages of variable arm impedance were also made clear in tracking tests where subjects preferred the larger hand controller inertias made possible by the acceleration feedback loop in the master arm. The ability to decouple the hand controller impedance from the slave arm dynamics is expected to be even more significant when the inertial properties of various payloads in the slave arm are considered.

Selective School Systems and Academic Self-Concept: How Explicit and Implicit School-Level Tracking Relate to the Big-Fish--Little-Pond Effect across Cultures

ERIC Educational Resources Information Center

Salchegger, Silvia

2016-01-01

A large body of research has demonstrated a big-fish--little-pond effect (BFLPE) by showing that equally able students have lower academic self-concepts in high-ability schools than in low-ability schools. Although the BFLPE generalizes across many countries, it varies significantly between countries. The reasons for this variation are still…

Examining the online reading behavior and performance of fifth-graders: evidence from eye-movement data

PubMed Central

Sung, Yao-Ting; Wu, Ming-Da; Chen, Chun-Kuang; Chang, Kuo-En

2015-01-01

Online reading is developing at an increasingly rapid rate, but the debate concerning whether learning is more effective when using hypertexts than when using traditional linear texts is still persistent. In addition, several researchers stated that online reading comprehension always starts with a question, but little empirical evidence has been gathered to investigate this claim. This study used eye-tracking technology and retrospective think aloud technique to examine online reading behaviors of fifth-graders (N = 50). The participants were asked to read four texts on the website. The present study employed a three-way mixed design: 2 (reading ability: high vs. low) × 2 (reading goals: with vs. without) × 2 (text types: hypertext vs. linear text). The dependent variables were eye-movement indices and the frequencies of using online reading strategy. The results show that fifth-graders, irrespective of their reading ability, found it difficult to navigate the non-linear structure of hypertexts when searching for and integrating information. When they read with goals, they adjusted their reading speed and the focus of their attention. Their offline reading ability also influenced their online reading performance. These results suggest that online reading skills and strategies have to be taught in order to enhance the online reading abilities of elementary-school students. PMID:26074837

Examining the online reading behavior and performance of fifth-graders: evidence from eye-movement data.

PubMed

Sung, Yao-Ting; Wu, Ming-Da; Chen, Chun-Kuang; Chang, Kuo-En

2015-01-01

Online reading is developing at an increasingly rapid rate, but the debate concerning whether learning is more effective when using hypertexts than when using traditional linear texts is still persistent. In addition, several researchers stated that online reading comprehension always starts with a question, but little empirical evidence has been gathered to investigate this claim. This study used eye-tracking technology and retrospective think aloud technique to examine online reading behaviors of fifth-graders (N = 50). The participants were asked to read four texts on the website. The present study employed a three-way mixed design: 2 (reading ability: high vs. low) × 2 (reading goals: with vs. without) × 2 (text types: hypertext vs. linear text). The dependent variables were eye-movement indices and the frequencies of using online reading strategy. The results show that fifth-graders, irrespective of their reading ability, found it difficult to navigate the non-linear structure of hypertexts when searching for and integrating information. When they read with goals, they adjusted their reading speed and the focus of their attention. Their offline reading ability also influenced their online reading performance. These results suggest that online reading skills and strategies have to be taught in order to enhance the online reading abilities of elementary-school students.

Laboratory testing of alcohol safety interlock systems employing divided attention tests

DOT National Transportation Integrated Search

1975-12-01

Author's abstract: Prototype Alcohol Safety Interlock Systems employing measurements of tracking ability, reaction time, and response accuracy to discern alcohol impairment were submitted to laboratory testing. These systems were modified versions of...

Simultaneous glacier surface elevation and flow velocity mapping from cross-track pushbroom satellite Imagery

NASA Astrophysics Data System (ADS)

Noh, M. J.; Howat, I. M.

2017-12-01

Glaciers and ice sheets are changing rapidly. Digital Elevation Models (DEMs) and Velocity Maps (VMs) obtained from repeat satellite imagery provide critical measurements of changes in glacier dynamics and mass balance over large, remote areas. DEMs created from stereopairs obtained during the same satellite pass through sensor re-pointing (i.e. "in-track stereo") have been most commonly used. In-track stereo has the advantage of minimizing the time separation and, thus, surface motion between image acquisitions, so that the ice surface can be assumed motionless in when collocating pixels between image pairs. Since the DEM extraction process assumes that all motion between collocated pixels is due to parallax or sensor model error, significant ice motion results in DEM quality loss or failure. In-track stereo, however, puts a greater demand on satellite tasking resources and, therefore, is much less abundant than single-scan imagery. Thus, if ice surface motion can be mitigated, the ability to extract surface elevation measurements from pairs of repeat single-scan "cross-track" imagery would greatly increase the extent and temporal resolution of ice surface change. Additionally, the ice motion measured by the DEM extraction process would itself provide a useful velocity measurement. We develop a novel algorithm for generating high-quality DEMs and VMs from cross-track image pairs without any prior information using the Surface Extraction from TIN-based Searchspace Minimization (SETSM) algorithm and its sensor model bias correction capabilities. Using a test suite of repeat, single-scan imagery from WorldView and QuickBird sensors collected over fast-moving outlet glaciers, we develop a method by which RPC biases between images are first calculated and removed over ice-free surfaces. Subpixel displacements over the ice are then constrained and used to correct the parallax estimate. Initial tests yield DEM results with the same quality as in-track stereo for cases where snowfall has not occurred between the two images and when the images have similar ground sample distances. The resulting velocity map also closely matches independent measurements.

3D terrain reconstruction using Chang’E-3 PCAM images

NASA Astrophysics Data System (ADS)

Chen, Wangli; Zeng, Xingguo; Zhang, Hongbo

2017-10-01

In order to improve understanding of the topography of Chang’E-3 landing site, 3D terrain models are reconstructed using PCMA images. PCAM (panoramic cameras) is a stereo camera system with a 27cm baseline on-board Yutu rover. It obtained panoramic images at four detection sites, and can achieve a resolution of 1.48mm/pixel at 10m. So the PCAM images reveal fine details of the detection region. In the method, SIFT is employed for feature description and feature matching. In addition to collinearity equations, the measure of baseline of the stereo system is also used in bundle adjustment to solve orientation parameters of all images. And then, pair-wise depth map computation is applied for dense surface reconstruction. Finally, DTM of the detection region is generated. The DTM covers an area with radius of about 20m, and centering at the location of the camera. In consequence of the design, each individual wheel of Yutu rover can leave three tracks on the surface of moon, and the width between the first and third track is 15cm, and these tracks are clear and distinguishable in images. So we chose the second detection site which is of the best ability of recognition of wheel tracks to evaluate the accuracy of the DTM. We measured the width of wheel tracks every 1.5m from the center of the detection region, and obtained 13 measures. It is noticed that the area where wheel tracks are ambiguous is avoided. Result shows that the mean value of wheel track width is 0.155m with a standard deviation of 0.007m. Generally, the closer to the center the more accurate the measure of wheel width is. This is due to the fact that the deformation of images aggravates with increase distance from the location of the camera, and this induces the decline of DTM quality in far areas. In our work, images of the four detection sites are adjusted independently, and this means that there is no tie point between different sites. So deviations between the locations of the same object measured from DTMs of adjacent detection sites may exist.

Robustness of neuroprosthetic decoding algorithms.

PubMed

Serruya, Mijail; Hatsopoulos, Nicholas; Fellows, Matthew; Paninski, Liam; Donoghue, John

2003-03-01

We assessed the ability of two algorithms to predict hand kinematics from neural activity as a function of the amount of data used to determine the algorithm parameters. Using chronically implanted intracortical arrays, single- and multineuron discharge was recorded during trained step tracking and slow continuous tracking tasks in macaque monkeys. The effect of increasing the amount of data used to build a neural decoding model on the ability of that model to predict hand kinematics accurately was examined. We evaluated how well a maximum-likelihood model classified discrete reaching directions and how well a linear filter model reconstructed continuous hand positions over time within and across days. For each of these two models we asked two questions: (1) How does classification performance change as the amount of data the model is built upon increases? (2) How does varying the time interval between the data used to build the model and the data used to test the model affect reconstruction? Less than 1 min of data for the discrete task (8 to 13 neurons) and less than 3 min (8 to 18 neurons) for the continuous task were required to build optimal models. Optimal performance was defined by a cost function we derived that reflects both the ability of the model to predict kinematics accurately and the cost of taking more time to build such models. For both the maximum-likelihood classifier and the linear filter model, increasing the duration between the time of building and testing the model within a day did not cause any significant trend of degradation or improvement in performance. Linear filters built on one day and tested on neural data on a subsequent day generated error-measure distributions that were not significantly different from those generated when the linear filters were tested on neural data from the initial day (p<0.05, Kolmogorov-Smirnov test). These data show that only a small amount of data from a limited number of cortical neurons appears to be necessary to construct robust models to predict kinematic parameters for the subsequent hours. Motor-control signals derived from neurons in motor cortex can be reliably acquired for use in neural prosthetic devices. Adequate decoding models can be built rapidly from small numbers of cells and maintained with daily calibration sessions.

A multiplexed magnetic tweezer with precision particle tracking and bi-directional force control.

PubMed

Johnson, Keith C; Clemmens, Emilie; Mahmoud, Hani; Kirkpatrick, Robin; Vizcarra, Juan C; Thomas, Wendy E

2017-01-01

In the past two decades, methods have been developed to measure the mechanical properties of single biomolecules. One of these methods, Magnetic tweezers, is amenable to aquisition of data on many single molecules simultaneously, but to take full advantage of this "multiplexing" ability, it is necessary to simultaneously incorprorate many capabilities that ahve been only demonstrated separately. Our custom built magnetic tweezer combines high multiplexing, precision bead tracking, and bi-directional force control into a flexible and stable platform for examining single molecule behavior. This was accomplished using electromagnets, which provide high temporal control of force while achieving force levels similar to permanent magnets via large paramagnetic beads. Here we describe the instrument and its ability to apply 2-260 pN of force on up to 120 beads simultaneously, with a maximum spatial precision of 12 nm using a variety of bead sizes and experimental techniques. We also demonstrate a novel method for increasing the precision of force estimations on heterogeneous paramagnetic beads using a combination of density separation and bi-directional force correlation which reduces the coefficient of variation of force from 27% to 6%. We then use the instrument to examine the force dependence of uncoiling and recoiling velocity of type 1 fimbriae from Eschericia coli ( E. coli ) bacteria, and see similar results to previous studies. This platform provides a simple, effective, and flexible method for efficiently gathering single molecule force spectroscopy measurements.

Nanoelectronics enabled chronic multimodal neural platform in a mouse ischemic model.

PubMed

Luan, Lan; Sullender, Colin T; Li, Xue; Zhao, Zhengtuo; Zhu, Hanlin; Wei, Xiaoling; Xie, Chong; Dunn, Andrew K

2018-02-01

Despite significant advancements of optical imaging techniques for mapping hemodynamics in small animal models, it remains challenging to combine imaging with spatially resolved electrical recording of individual neurons especially for longitudinal studies. This is largely due to the strong invasiveness to the living brain from the penetrating electrodes and their limited compatibility with longitudinal imaging. We implant arrays of ultraflexible nanoelectronic threads (NETs) in mice for neural recording both at the brain surface and intracortically, which maintain great tissue compatibility chronically. By mounting a cranial window atop of the NET arrays that allows for chronic optical access, we establish a multimodal platform that combines spatially resolved electrical recording of neural activity and laser speckle contrast imaging (LSCI) of cerebral blood flow (CBF) for longitudinal studies. We induce peri-infarct depolarizations (PIDs) by targeted photothrombosis, and show the ability to detect its occurrence and propagation through spatiotemporal variations in both extracellular potentials and CBF. We also demonstrate chronic tracking of single-unit neural activity and CBF over days after photothrombosis, from which we observe reperfusion and increased firing rates. This multimodal platform enables simultaneous mapping of neural activity and hemodynamic parameters at the microscale for quantitative, longitudinal comparisons with minimal perturbation to the baseline neurophysiology. The ability to spatiotemporally resolve and chronically track CBF and neural electrical activity in the same living brain region has broad applications for studying the interplay between neural and hemodynamic responses in health and in cerebrovascular and neurological pathologies. Copyright © 2017 Elsevier B.V. All rights reserved.

Screening for Dyslexia Using Eye Tracking during Reading.

PubMed

Nilsson Benfatto, Mattias; Öqvist Seimyr, Gustaf; Ygge, Jan; Pansell, Tony; Rydberg, Agneta; Jacobson, Christer

2016-01-01

Dyslexia is a neurodevelopmental reading disability estimated to affect 5-10% of the population. While there is yet no full understanding of the cause of dyslexia, or agreement on its precise definition, it is certain that many individuals suffer persistent problems in learning to read for no apparent reason. Although it is generally agreed that early intervention is the best form of support for children with dyslexia, there is still a lack of efficient and objective means to help identify those at risk during the early years of school. Here we show that it is possible to identify 9-10 year old individuals at risk of persistent reading difficulties by using eye tracking during reading to probe the processes that underlie reading ability. In contrast to current screening methods, which rely on oral or written tests, eye tracking does not depend on the subject to produce some overt verbal response and thus provides a natural means to objectively assess the reading process as it unfolds in real-time. Our study is based on a sample of 97 high-risk subjects with early identified word decoding difficulties and a control group of 88 low-risk subjects. These subjects were selected from a larger population of 2165 school children attending second grade. Using predictive modeling and statistical resampling techniques, we develop classification models from eye tracking records less than one minute in duration and show that the models are able to differentiate high-risk subjects from low-risk subjects with high accuracy. Although dyslexia is fundamentally a language-based learning disability, our results suggest that eye movements in reading can be highly predictive of individual reading ability and that eye tracking can be an efficient means to identify children at risk of long-term reading difficulties.

Impact of a scholarly track on quality of residency program applicants.

PubMed

Celebi, Julie M; Nguyen, Cathina T; Sattler, Amelia L; Stevens, Michael B; Lin, Steven Y

2016-11-01

It is generally believed that residency programs offering scholarly tracks attract higher quality applicants, although there is little evidence of this in the literature. We explored the impact of a clinician-educator track on the quality of applicants to our residency program by comparing the volume and characteristics of applicants before (2008-2011) and after (2012-2015) the track was introduced. The total number of applications received was compared between the pre-track and post-track years. Among interviewees, data on United States Medical Licensing Examination (USMLE) Step 1 scores, Step 2 Clinical Knowledge (CK) scores, Medical Student Performance Evaluation (MSPE) scores, and proportion of candidates with an advanced degree (e.g. MPH, PhD) were compared. An online survey was administered to all interviewees in 2014-2015 to measure interest in the track. The total number of applications to the residency program increased significantly from the pre-track to the post-track years. Compared to the pre-track years, interviewees during the post-track years had statistically higher USMLE Step 1 and Step 2 CK scores, better MSPE scores, and were more likely to have an advanced degree. Two-thirds of survey respondents reported that the track increased their interest in the residency program. A residency clinician-educator track may be associated with increased overall interest from applicants, higher application volume, and better measures of applicant quality based on USMLE scores, MSPE scores, and proportion of candidates with an advanced degree. Residency programs may consider a potential increase in the quality of their applicants as an added benefit of offering a scholarly track.

A simple device to assess and train motor coordination.

PubMed

Petrofsky, J S; Petrofsky, D

2004-01-01

The purpose of this project was to develop a computer program which can be used on a laptop or other IBM-based computer to assess and train motor coordination in children with closed head trauma or cerebral palsy. Muscle coordination was assessed by the child's ability to track a series of lines of increasing complexity. A stylus was used by the child to trace lines on a computer screen. Two different line tests were used. In the first, lines of various complexities were drawn on the screen at various angles. The child was asked to trace the line and the accuracy with which the line was traced was determined, providing a score. In a second test, a line was drawn on the screen and the child was asked to trace the line as it was drawn. The error in tracking the line and the time to track the line both were used to evaluate and score the child's performance. Finally, a 'Winnie the Pooh' character was flashed on the screen with distracters such as trees and other animals, and the child was asked to touch the Pooh. By increasing the speed of movement and decreasing the duration that the characters appeared on the screen, the child could be challenged. Successful touching of a character resulted in a positive score. Six children with cerebral palsy were compared to five children who did not have cerebral palsy, to evaluate the device. While both groups of children showed an increase in motor skills using the program, the increase seen in the children with cerebral palsy was 5-fold greater than that of the control group. While only a few children were tested with the device, the device seems to prove quite useful for physical and occupational therapy for working on motor skills in children. More investigation is warranted.

Weed or wheel! FMRI, behavioural, and toxicological investigations of how cannabis smoking affects skills necessary for driving.

PubMed

Battistella, Giovanni; Fornari, Eleonora; Thomas, Aurélien; Mall, Jean-Frédéric; Chtioui, Haithem; Appenzeller, Monique; Annoni, Jean-Marie; Favrat, Bernard; Maeder, Philippe; Giroud, Christian

2013-01-01

Marijuana is the most widely used illicit drug, however its effects on cognitive functions underlying safe driving remain mostly unexplored. Our goal was to evaluate the impact of cannabis on the driving ability of occasional smokers, by investigating changes in the brain network involved in a tracking task. The subject characteristics, the percentage of Δ(9)-Tetrahydrocannabinol in the joint, and the inhaled dose were in accordance with real-life conditions. Thirty-one male volunteers were enrolled in this study that includes clinical and toxicological aspects together with functional magnetic resonance imaging of the brain and measurements of psychomotor skills. The fMRI paradigm was based on a visuo-motor tracking task, alternating active tracking blocks with passive tracking viewing and rest condition. We show that cannabis smoking, even at low Δ(9)-Tetrahydrocannabinol blood concentrations, decreases psychomotor skills and alters the activity of the brain networks involved in cognition. The relative decrease of Blood Oxygen Level Dependent response (BOLD) after cannabis smoking in the anterior insula, dorsomedial thalamus, and striatum compared to placebo smoking suggests an alteration of the network involved in saliency detection. In addition, the decrease of BOLD response in the right superior parietal cortex and in the dorsolateral prefrontal cortex indicates the involvement of the Control Executive network known to operate once the saliencies are identified. Furthermore, cannabis increases activity in the rostral anterior cingulate cortex and ventromedial prefrontal cortices, suggesting an increase in self-oriented mental activity. Subjects are more attracted by intrapersonal stimuli ("self") and fail to attend to task performance, leading to an insufficient allocation of task-oriented resources and to sub-optimal performance. These effects correlate with the subjective feeling of confusion rather than with the blood level of Δ(9)-Tetrahydrocannabinol. These findings bolster the zero-tolerance policy adopted in several countries that prohibits the presence of any amount of drugs in blood while driving.

Weed or Wheel! fMRI, Behavioural, and Toxicological Investigations of How Cannabis Smoking Affects Skills Necessary for Driving

PubMed Central

Thomas, Aurélien; Mall, Jean-Frédéric; Chtioui, Haithem; Appenzeller, Monique; Annoni, Jean-Marie; Favrat, Bernard

2013-01-01

Marijuana is the most widely used illicit drug, however its effects on cognitive functions underling safe driving remain mostly unexplored. Our goal was to evaluate the impact of cannabis on the driving ability of occasional smokers, by investigating changes in the brain network involved in a tracking task. The subject characteristics, the percentage of Δ9-Tetrahydrocannabinol in the joint, and the inhaled dose were in accordance with real-life conditions. Thirty-one male volunteers were enrolled in this study that includes clinical and toxicological aspects together with functional magnetic resonance imaging of the brain and measurements of psychomotor skills. The fMRI paradigm was based on a visuo-motor tracking task, alternating active tracking blocks with passive tracking viewing and rest condition. We show that cannabis smoking, even at low Δ9-Tetrahydrocannabinol blood concentrations, decreases psychomotor skills and alters the activity of the brain networks involved in cognition. The relative decrease of Blood Oxygen Level Dependent response (BOLD) after cannabis smoking in the anterior insula, dorsomedial thalamus, and striatum compared to placebo smoking suggests an alteration of the network involved in saliency detection. In addition, the decrease of BOLD response in the right superior parietal cortex and in the dorsolateral prefrontal cortex indicates the involvement of the Control Executive network known to operate once the saliencies are identified. Furthermore, cannabis increases activity in the rostral anterior cingulate cortex and ventromedial prefrontal cortices, suggesting an increase in self-oriented mental activity. Subjects are more attracted by intrapersonal stimuli (“self”) and fail to attend to task performance, leading to an insufficient allocation of task-oriented resources and to sub-optimal performance. These effects correlate with the subjective feeling of confusion rather than with the blood level of Δ9-Tetrahydrocannabinol. These findings bolster the zero-tolerance policy adopted in several countries that prohibits the presence of any amount of drugs in blood while driving. PMID:23300977

Photonic sensor applications in transportation security

NASA Astrophysics Data System (ADS)

Krohn, David A.

2007-09-01

There is a broad range of security sensing applications in transportation that can be facilitated by using fiber optic sensors and photonic sensor integrated wireless systems. Many of these vital assets are under constant threat of being attacked. It is important to realize that the threats are not just from terrorism but an aging and often neglected infrastructure. To specifically address transportation security, photonic sensors fall into two categories: fixed point monitoring and mobile tracking. In fixed point monitoring, the sensors monitor bridge and tunnel structural health and environment problems such as toxic gases in a tunnel. Mobile tracking sensors are being designed to track cargo such as shipboard cargo containers and trucks. Mobile tracking sensor systems have multifunctional sensor requirements including intrusion (tampering), biochemical, radiation and explosives detection. This paper will review the state of the art of photonic sensor technologies and their ability to meet the challenges of transportation security.

Intelligent Tracking Control for a Class of Uncertain High-Order Nonlinear Systems.

PubMed

Zhao, Xudong; Shi, Peng; Zheng, Xiaolong; Zhang, Jianhua

2016-09-01

This brief is concerned with the problem of intelligent tracking control for a class of high-order nonlinear systems with completely unknown nonlinearities. An intelligent adaptive control algorithm is presented by combining the adaptive backstepping technique with the neural networks' approximation ability. It is shown that the practical output tracking performance of the system is achieved using the proposed state-feedback controller under two mild assumptions. In particular, by introducing a parameter in the derivations, the tracking error between the time-varying target signal and the output can be reduced via tuning the controller design parameters. Moreover, in order to solve the problem of overparameterization, which is a common issue in adaptive control design, a controller with one adaptive law is also designed. Finally, simulation results are given to show the effectiveness of the theoretical approaches and the potential of the proposed new design techniques.

Voice tracking and spoken word recognition in the presence of other voices

NASA Astrophysics Data System (ADS)

Litong-Palima, Marisciel; Violanda, Renante; Saloma, Caesar

2004-12-01

We study the human hearing process by modeling the hair cell as a thresholded Hopf bifurcator and compare our calculations with experimental results involving human subjects in two different multi-source listening tasks of voice tracking and spoken-word recognition. In the model, we observed noise suppression by destructive interference between noise sources which weakens the effective noise strength acting on the hair cell. Different success rate characteristics were observed for the two tasks. Hair cell performance at low threshold levels agree well with results from voice-tracking experiments while those of word-recognition experiments are consistent with a linear model of the hearing process. The ability of humans to track a target voice is robust against cross-talk interference unlike word-recognition performance which deteriorates quickly with the number of uncorrelated noise sources in the environment which is a response behavior that is associated with linear systems.

New color-based tracking algorithm for joints of the upper extremities

NASA Astrophysics Data System (ADS)

Wu, Xiangping; Chow, Daniel H. K.; Zheng, Xiaoxiang

2007-11-01

To track the joints of the upper limb of stroke sufferers for rehabilitation assessment, a new tracking algorithm which utilizes a developed color-based particle filter and a novel strategy for handling occlusions is proposed in this paper. Objects are represented by their color histogram models and particle filter is introduced to track the objects within a probability framework. Kalman filter, as a local optimizer, is integrated into the sampling stage of the particle filter that steers samples to a region with high likelihood and therefore fewer samples is required. A color clustering method and anatomic constraints are used in dealing with occlusion problem. Compared with the general basic particle filtering method, the experimental results show that the new algorithm has reduced the number of samples and hence the computational consumption, and has achieved better abilities of handling complete occlusion over a few frames.

On-Line Tracking Controller for Brushless DC Motor Drives Using Artificial Neural Networks

NASA Technical Reports Server (NTRS)

Rubaai, Ahmed

1996-01-01

A real-time control architecture is developed for time-varying nonlinear brushless dc motors operating in a high performance drives environment. The developed control architecture possesses the capabilities of simultaneous on-line identification and control. The dynamics of the motor are modeled on-line and controlled using an artificial neural network, as the system runs. The control architecture combines the experience and dependability of adaptive tracking systems with potential and promise of the neural computing technology. The sensitivity of real-time controller to parametric changes that occur during training is investigated. Such changes are usually manifested by rapid changes in the load of the brushless motor drives. This sudden change in the external load is simulated for the sigmoidal and sinusoidal reference tracks. The ability of the neuro-controller to maintain reasonable tracking accuracy in the presence of external noise is also verified for a number of desired reference trajectories.

A simple behaviour provides accuracy and flexibility in odour plume tracking--the robotic control of sensory-motor coupling in silkmoths.

PubMed

Ando, Noriyasu; Kanzaki, Ryohei

2015-12-01

Odour plume tracking is an essential behaviour for animal survival. A fundamental strategy for this is to move upstream and then across-stream. Male silkmoths, Bombyx mori, display this strategy as a pre-programmed sequential behaviour. They walk forward (surge) in response to the female sex pheromone and perform a zigzagging 'mating dance'. Though pre-programmed, the surge direction is modulated by bilateral olfactory input and optic flow. However, the nature of the interaction between these two sensory modalities and contribution of the resultant motor command to localizing an odour source are still unknown. We evaluated the ability of the silkmoth to localize an odour source under conditions of disturbed sensory-motor coupling, using a silkmoth-driven mobile robot. The significance of the bilateral olfaction of the moth was confirmed by inverting the olfactory input to the antennae, or its motor output. Inversion of the motor output induced consecutive circling, which was inhibited by covering the visual field of the moth. This suggests that the corollary discharge from the motor command and the reafference of self-generated optic flow generate compensatory signals to guide the surge accurately. Additionally, after inverting the olfactory input, the robot successfully tracked the odour plume by using a combination of behaviours. These results indicate that accurate guidance of the reflexive surge by integrating bilateral olfactory and visual information with innate pre-programmed behaviours increases the flexibility to track an odour plume even under disturbed circumstances. © 2015. Published by The Company of Biologists Ltd.

Robust tracking and quantification of C. elegans body shape and locomotion through coiling, entanglement, and omega bends

PubMed Central

Roussel, Nicolas; Sprenger, Jeff; Tappan, Susan J; Glaser, Jack R

2014-01-01

The behavior of the well-characterized nematode, Caenorhabditis elegans (C. elegans), is often used to study the neurologic control of sensory and motor systems in models of health and neurodegenerative disease. To advance the quantification of behaviors to match the progress made in the breakthroughs of genetics, RNA, proteins, and neuronal circuitry, analysis must be able to extract subtle changes in worm locomotion across a population. The analysis of worm crawling motion is complex due to self-overlap, coiling, and entanglement. Using current techniques, the scope of the analysis is typically restricted to worms to their non-occluded, uncoiled state which is incomplete and fundamentally biased. Using a model describing the worm shape and crawling motion, we designed a deformable shape estimation algorithm that is robust to coiling and entanglement. This model-based shape estimation algorithm has been incorporated into a framework where multiple worms can be automatically detected and tracked simultaneously throughout the entire video sequence, thereby increasing throughput as well as data validity. The newly developed algorithms were validated against 10 manually labeled datasets obtained from video sequences comprised of various image resolutions and video frame rates. The data presented demonstrate that tracking methods incorporated in WormLab enable stable and accurate detection of these worms through coiling and entanglement. Such challenging tracking scenarios are common occurrences during normal worm locomotion. The ability for the described approach to provide stable and accurate detection of C. elegans is critical to achieve unbiased locomotory analysis of worm motion. PMID:26435884

Weighing Scale-Based Pulse Transit Time is a Superior Marker of Blood Pressure than Conventional Pulse Arrival Time

PubMed Central

Martin, Stephanie L.-O.; Carek, Andrew M.; Kim, Chang-Sei; Ashouri, Hazar; Inan, Omer T.; Hahn, Jin-Oh; Mukkamala, Ramakrishna

2016-01-01

Pulse transit time (PTT) is being widely pursued for cuff-less blood pressure (BP) monitoring. Most efforts have employed the time delay between ECG and finger photoplethysmography (PPG) waveforms as a convenient surrogate of PTT. However, these conventional pulse arrival time (PAT) measurements include the pre-ejection period (PEP) and the time delay through small, muscular arteries and may thus be an unreliable marker of BP. We assessed a bathroom weighing scale-like system for convenient measurement of ballistocardiography and foot PPG waveforms – and thus PTT through larger, more elastic arteries – in terms of its ability to improve tracking of BP in individual subjects. We measured “scale PTT”, conventional PAT, and cuff BP in humans during interventions that increased BP but changed PEP and smooth muscle contraction differently. Scale PTT tracked the diastolic BP changes well, with correlation coefficient of −0.80 ± 0.02 (mean ± SE) and root-mean-squared-error of 7.6 ± 0.5 mmHg after a best-case calibration. Conventional PAT was significantly inferior in tracking these changes, with correlation coefficient of −0.60 ± 0.04 and root-mean-squared-error of 14.6 ± 1.5 mmHg (p < 0.05). Scale PTT also tracked the systolic BP changes better than conventional PAT but not to an acceptable level. With further development, scale PTT may permit reliable, convenient measurement of BP. PMID:27976741

Optimizing the fine lock performance of the Hubble Space Telescope fine guidance sensors

NASA Technical Reports Server (NTRS)

Eaton, David J.; Whittlesey, Richard; Abramowicz-Reed, Linda; Zarba, Robert

1993-01-01

This paper summarizes the on-orbit performance to date of the three Hubble Space Telescope Fine Guidance Sensors (FGS's) in Fine Lock mode, with respect to acquisition success rate, ability to maintain lock, and star brightness range. The process of optimizing Fine Lock performance, including the reasoning underlying the adjustment of uplink parameters, and the effects of optimization are described. The Fine Lock optimization process has combined theoretical and experimental approaches. Computer models of the FGS have improved understanding of the effects of uplink parameters and fine error averaging on the ability of the FGS to acquire stars and maintain lock. Empirical data have determined the variation of the interferometric error characteristics (so-called 's-curves') between FGS's and over each FGS field of view, identified binary stars, and quantified the systematic error in Coarse Track (the mode preceding Fine Lock). On the basis of these empirical data, the values of the uplink parameters can be selected more precisely. Since launch, optimization efforts have improved FGS Fine Lock performance, particularly acquisition, which now enjoys a nearly 100 percent success rate. More recent work has been directed towards improving FGS tolerance of two conditions that exceed its original design requirements. First, large amplitude spacecraft jitter is induced by solar panel vibrations following day/night transitions. This jitter is generally much greater than the FGS's were designed to track, and while the tracking ability of the FGS's has been shown to exceed design requirements, losses of Fine Lock after day/night transitions are frequent. Computer simulations have demonstrated a potential improvement in Fine Lock tracking of vehicle jitter near terminator crossings. Second, telescope spherical aberration degrades the interferometric error signal in Fine Lock, but use of the FGS two-thirds aperture stop restores the transfer function with a corresponding loss of throughput. This loss requires the minimum brightness of acquired stars to be about one magnitude brighter than originally planned.

Forward-backward multiplicity correlations of target fragments in nucleus-emulsion collisions at a few hundred MeV/u

NASA Astrophysics Data System (ADS)

Zhang, Dong-Hai; Chen, Yan-Ling; Wang, Guo-Rong; Li, Wang-Dong; Wang, Qing; Yao, Ji-Jie; Zhou, Jian-Guo; Li, Rong; Li, Jun-Sheng; Li, Hui-Ling

2015-01-01

The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV 12C, 400 A MeV 12C, 400 A MeV 20Ne and 500 A MeV 56Fe induced different types of nuclear emulsion target interactions are investigated. It is found that the forward and backward averaged multiplicity of a grey, black and heavily ionized track particle increases with the increase of the target size. The averaged multiplicity of a forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of a forward grey track particle increases with an increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with an increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets.

On the effect of unsupported sleepers on the dynamic behaviour of a railway track

NASA Astrophysics Data System (ADS)

Zhu, J. Y.; Thompson, D. J.; Jones, C. J. C.

2011-09-01

The effect of unsupported sleepers on the dynamic behaviour of a railway track is studied based on vehicle-track dynamic interaction theory, using a model of the track as a Timoshenko beam supported on a periodic elastic foundation. Considering the vehicle's running speed and the number of unsupported sleepers, the track dynamic characteristics are investigated and verified in the time and frequency domains by experiments on a 1:5 scale model wheel-rail test rig. The results show that when hanging sleepers are present, leading to a discontinuous and irregular track support, additional wheel-rail interaction forces are generated. These forces increase as further sleepers become unsupported and as the vehicle's running speed increases. The adjacent supports experience increased dynamic forces which will lead to further deterioration of track quality and the formation of long wavelength track irregularities, which worsen the vehicles' running stability and riding comfort. Stationary transfer functions measurements of the dynamic behaviour of the track are also presented to support the findings.

Tracking a Very Near Earth Asteroid

NASA Astrophysics Data System (ADS)

Bruck, R.; Rashid, S.; Peppard, T.

2013-09-01

The potential effects of an asteroid passing within close proximity to the Earth were recently realized. During the February 16, 2013 event, Asteroid 2012 DA14 passed within an estimated 27,700 kilometers of the earth, well within the geosynchronous (GEO) orbital belt. This was the closest known approach of a planetoid of this size, in modern history. The GEO belt is a region that is filled with critical communications satellites which provide relays for essential government, business and private datum. On the day of the event, optical instruments at Detachment 3, 21OG, Maui GEODSS were able to open in marginal atmospheric conditions, locate and collect metric and raw video data on the asteroid as it passed a point of near heliocentric orbital propinquity to the Earth. Prior to the event, the Joint Space Operations Center (JSpOC) used propagated trajectory data from NASA's Near Earth Object Program Office at the Jet Propulsion Laboratory to assess potential collisions with man-made objects in Earth orbit. However, the ability to actively track this asteroid through the populated satellite belt not only allowed surveillance for possible late orbital perturbations of the asteroid, but, afforded the ability to monitor possible strikes on all other orbiting bodies of anthropogenic origin either not in orbital catalogs or not recently updated in those catalogs. Although programmed only for tracking satellites in geocentric orbits, GEODSS was able to compensate and maintain track on DA14, collecting one hundred and fifty four metric observations during the event.

An Adaptive Neural Mechanism for Acoustic Motion Perception with Varying Sparsity

PubMed Central

Shaikh, Danish; Manoonpong, Poramate

2017-01-01

Biological motion-sensitive neural circuits are quite adept in perceiving the relative motion of a relevant stimulus. Motion perception is a fundamental ability in neural sensory processing and crucial in target tracking tasks. Tracking a stimulus entails the ability to perceive its motion, i.e., extracting information about its direction and velocity. Here we focus on auditory motion perception of sound stimuli, which is poorly understood as compared to its visual counterpart. In earlier work we have developed a bio-inspired neural learning mechanism for acoustic motion perception. The mechanism extracts directional information via a model of the peripheral auditory system of lizards. The mechanism uses only this directional information obtained via specific motor behaviour to learn the angular velocity of unoccluded sound stimuli in motion. In nature however the stimulus being tracked may be occluded by artefacts in the environment, such as an escaping prey momentarily disappearing behind a cover of trees. This article extends the earlier work by presenting a comparative investigation of auditory motion perception for unoccluded and occluded tonal sound stimuli with a frequency of 2.2 kHz in both simulation and practice. Three instances of each stimulus are employed, differing in their movement velocities–0.5°/time step, 1.0°/time step and 1.5°/time step. To validate the approach in practice, we implement the proposed neural mechanism on a wheeled mobile robot and evaluate its performance in auditory tracking. PMID:28337137

Cellphone probes as an ATMS tool

DOT National Transportation Integrated Search

2003-06-01

The foundation of traffic operations and management is the ability to monitor traffic conditions. One approach to traffic monitoring is to sample conditions by tracking a limited number of probe vehicles as they traverse a network. An emerging techno...

The Behavioral and Neural Mechanisms Underlying the Tracking of Expertise

PubMed Central

Boorman, Erie D.; O’Doherty, John P.; Adolphs, Ralph; Rangel, Antonio

2013-01-01

Summary Evaluating the abilities of others is fundamental for successful economic and social behavior. We investigated the computational and neurobiological basis of ability tracking by designing an fMRI task that required participants to use and update estimates of both people and algorithms’ expertise through observation of their predictions. Behaviorally, we find a model-based algorithm characterized subject predictions better than several alternative models. Notably, when the agent’s prediction was concordant rather than discordant with the subject’s own likely prediction, participants credited people more than algorithms for correct predictions and penalized them less for incorrect predictions. Neurally, many components of the mentalizing network—medial prefrontal cortex, anterior cingulate gyrus, temporoparietal junction, and precuneus—represented or updated expertise beliefs about both people and algorithms. Moreover, activity in lateral orbitofrontal and medial prefrontal cortex reflected behavioral differences in learning about people and algorithms. These findings provide basic insights into the neural basis of social learning. PMID:24360551

Potential Application of a Graphical Processing Unit to Parallel Computations in the NUBEAM Code

NASA Astrophysics Data System (ADS)

Payne, J.; McCune, D.; Prater, R.

2010-11-01

NUBEAM is a comprehensive computational Monte Carlo based model for neutral beam injection (NBI) in tokamaks. NUBEAM computes NBI-relevant profiles in tokamak plasmas by tracking the deposition and the slowing of fast ions. At the core of NUBEAM are vector calculations used to track fast ions. These calculations have recently been parallelized to run on MPI clusters. However, cost and interlink bandwidth limit the ability to fully parallelize NUBEAM on an MPI cluster. Recent implementation of double precision capabilities for Graphical Processing Units (GPUs) presents a cost effective and high performance alternative or complement to MPI computation. Commercially available graphics cards can achieve up to 672 GFLOPS double precision and can handle hundreds of thousands of threads. The ability to execute at least one thread per particle simultaneously could significantly reduce the execution time and the statistical noise of NUBEAM. Progress on implementation on a GPU will be presented.

Reproducibility of apatite fission-track length data and thermal history reconstruction

NASA Astrophysics Data System (ADS)

Ketcham, Richard A.; Donelick, Raymond A.; Balestrieri, Maria Laura; Zattin, Massimiliano

2009-07-01

The ability to derive detailed thermal history information from apatite fission-track analysis is predicated on the reliability of track length measurements. However, insufficient attention has been given to whether and how these measurements should be standardized. In conjunction with a fission-track workshop we conducted an experiment in which 11 volunteers measured ~ 50 track lengths on one or two samples. One mount contained Durango apatite with unannealed induced tracks, and one contained apatite from a crystalline rock containing spontaneous tracks with a broad length distribution caused by partial resetting. Results for both mounts showed scatter indicative of differences in measurement technique among the individual analysts. The effects of this variability on thermal history inversion were tested using the HeFTy computer program to model the spontaneous track measurements. A cooling-only scenario and a reheating scenario more consistent with the sample's geological history were posed. When a uniform initial length value from the literature was used, results among analysts were very inconsistent in both scenarios, although normalizing for track angle by projecting all lengths to a c-axis parallel crystallographic orientation improved some aspects of congruency. When the induced track measurement was used as the basis for thermal history inversion congruency among analysts, and agreement with inversions based on data previously collected, was significantly improved. Further improvement was obtained by using c-axis projection. Differences among inversions that persisted could be traced to differential sampling of long- and short-track populations among analysts. The results of this study, while demonstrating the robustness of apatite fission-track thermal history inversion, nevertheless point to the necessity for a standardized length calibration schema that accounts for analyst variation.

STS-43 TDRS-E & IUS over the Pacific Ocean after deployment from OV-104's PLB

NASA Image and Video Library

1991-08-02

STS043-601-033 (2 Aug 1991) --- The Tracking and Data Relay Satellite (TDRS-E), is seen almost as a silhouette in this 70mm image. The TDRS spacecraft was captured on film as it moved away from the earth-orbiting Atlantis a mere six hours after the shuttle was launched from Pad 39A at Kennedy Space Center, Florida. TDRS, built by TRW, will be placed in a geosynchronous orbit and after on-orbit testing, which requires several weeks, will be designated TDRS-5. The communications satellite will replace TDRS-3 at 174 degrees west longitude. The backbone of NASA's space-to-ground communications, the Tracking and Data Relay Satellites have increased NASA's ability to send and receive data to spacecraft in low-earth orbit to more than 85 percent of the time. Before TDRS, NASA relied solely on a system of ground stations that permitted communications only 15 percent of the time. Increased coverage has allowed on-orbit repairs, live television broadcast from space and continuous dialogues between astronaut crews and ground control during critical periods such as space shuttle landings. The five astronauts of the STS-43 are John E. Blaha, mission commander, Michael a. Baker, pilot, and mission specialists Shannon W. Lucid, G. David Low and James C. Adamson.

Could the Pharmaceutical Industry Benefit from Full-Scale Adoption of Radio-Frequency Identification (RFID) Technology with New Regulations?

PubMed

Coustasse, Alberto; Kimble, Craig A; Stanton, Robert B; Naylor, Mariah

2016-01-01

Healthcare regulators are directing attention to the pharmaceutical supply chain with the passage of the Drug Quality and Security Act (DQSA) and the Drug Supply Chain Security Act (DSCSA). Adoption of Radio-Frequency Identification (RFID) technology has the ability to improve compliance, reduce costs, and improve safety in the supply chain but its implementation has been limited; primarily because of hardware and tag costs. The purpose of this research study was to analyze the benefits to the pharmaceutical industry and healthcare system of the adoption of RFID technology as a result of newly implemented supply chain regulations. The methodology was a review following the steps of a systematic review with a total of 96 sources used. With the DSCSA, pharmaceutical companies must track and trace prescription drugs across the supply chain, and RFID can resolve many track-and-trace issues with manufacturer control of data. The practical implication of this study is that pharmaceutical companies must continue to have the potential to increase revenues, decrease associated costs, and increase compliance with new FDA regulations with RFID. Still, challenges related to regulatory statute wording, implementation of two-dimensional barcode technology, and the variety of interfaces within the pharmaceutical supply chain have delayed adoption and its full implementation.

Could the Pharmaceutical Industry Benefit from Full-Scale Adoption of Radio-Frequency Identification (RFID) Technology with New Regulations?

PubMed Central

Coustasse, Alberto; Kimble, Craig A.; Stanton, Robert B.; Naylor, Mariah

2016-01-01

Healthcare regulators are directing attention to the pharmaceutical supply chain with the passage of the Drug Quality and Security Act (DQSA) and the Drug Supply Chain Security Act (DSCSA). Adoption of Radio-Frequency Identification (RFID) technology has the ability to improve compliance, reduce costs, and improve safety in the supply chain but its implementation has been limited; primarily because of hardware and tag costs. The purpose of this research study was to analyze the benefits to the pharmaceutical industry and healthcare system of the adoption of RFID technology as a result of newly implemented supply chain regulations. The methodology was a review following the steps of a systematic review with a total of 96 sources used. With the DSCSA, pharmaceutical companies must track and trace prescription drugs across the supply chain, and RFID can resolve many track-and-trace issues with manufacturer control of data. The practical implication of this study is that pharmaceutical companies must continue to have the potential to increase revenues, decrease associated costs, and increase compliance with new FDA regulations with RFID. Still, challenges related to regulatory statute wording, implementation of two-dimensional barcode technology, and the variety of interfaces within the pharmaceutical supply chain have delayed adoption and its full implementation. PMID:27843419

A Novel Loss Recovery and Tracking Scheme for Maneuvering Target in Hybrid WSNs.

PubMed

Qian, Hanwang; Fu, Pengcheng; Li, Baoqing; Liu, Jianpo; Yuan, Xiaobing

2018-01-25

Tracking a mobile target, which aims to timely monitor the invasion of specific target, is one of the most prominent applications in wireless sensor networks (WSNs). Traditional tracking methods in WSNs only based on static sensor nodes (SNs) have several critical problems. For example, to void the loss of mobile target, many SNs must be active to track the target in all possible directions, resulting in excessive energy consumption. Additionally, when entering coverage holes in the monitoring area, the mobile target may be missing and then its state is unknown during this period. To tackle these problems, in this paper, a few mobile sensor nodes (MNs) are introduced to cooperate with SNs to form a hybrid WSN due to their stronger abilities and less constrained energy. Then, we propose a valid target tracking scheme for hybrid WSNs to dynamically schedule the MNs and SNs. Moreover, a novel loss recovery mechanism is proposed to find the lost target and recover the tracking with fewer SNs awakened. Furthermore, to improve the robustness and accuracy of the recovery mechanism, an adaptive unscented Kalman filter (AUKF) algorithm is raised to dynamically adjust the process noise covariance. Simulation results demonstrate that our tracking scheme for maneuvering target in hybrid WSNs can not only track the target effectively even if the target is lost but also maintain an excellent accuracy and robustness with fewer activated nodes.

A Novel Loss Recovery and Tracking Scheme for Maneuvering Target in Hybrid WSNs

PubMed Central

Liu, Jianpo; Yuan, Xiaobing

2018-01-01

Tracking a mobile target, which aims to timely monitor the invasion of specific target, is one of the most prominent applications in wireless sensor networks (WSNs). Traditional tracking methods in WSNs only based on static sensor nodes (SNs) have several critical problems. For example, to void the loss of mobile target, many SNs must be active to track the target in all possible directions, resulting in excessive energy consumption. Additionally, when entering coverage holes in the monitoring area, the mobile target may be missing and then its state is unknown during this period. To tackle these problems, in this paper, a few mobile sensor nodes (MNs) are introduced to cooperate with SNs to form a hybrid WSN due to their stronger abilities and less constrained energy. Then, we propose a valid target tracking scheme for hybrid WSNs to dynamically schedule the MNs and SNs. Moreover, a novel loss recovery mechanism is proposed to find the lost target and recover the tracking with fewer SNs awakened. Furthermore, to improve the robustness and accuracy of the recovery mechanism, an adaptive unscented Kalman filter (AUKF) algorithm is raised to dynamically adjust the process noise covariance. Simulation results demonstrate that our tracking scheme for maneuvering target in hybrid WSNs can not only track the target effectively even if the target is lost but also maintain an excellent accuracy and robustness with fewer activated nodes. PMID:29370103

Asset tracking: what it is and whether it's right for you.

PubMed

2006-10-01

This Guidance Article examines asset tracking technology, reviewing what it is, how it works, and how it can be applied in the healthcare setting to help hospitals better manage medical equipment. The article also offers guidance to help healthcare facilities determine whether (or when) they should consider investing in asset tracking technology. Asset tracking refers to the ability to detect, identify, and locate assets-infusion pumps, wheelchairs, or just about any other object or device--at any time, as well as to record the physical locations of those assets over time. Though already commonplace in some industries, tracking technology is still relatively new to healthcare. As a result, the systems, the companies that supply them, and even the applications for which they can be used are still evolving. While some healthcare facilities could see almost immediate benefits from implementing an asset tracking system now, others would benefit from waiting a little while for the marketplace to develop further. This article provides information to help hospitals determine which option will be best for them. For facilities that choose to start the system selection process now, we outline factors that should be considered.

High Speed A/D DSP Interface for Carrier Doppler Tracking

NASA Technical Reports Server (NTRS)

Baggett, Timothy

1998-01-01

As on-board satellite systems continue to increase in ability to perform self diagnostic checks, it will become more important for satellites to initiate ground communications contact. Currently, the NASA Space Network requires users to pre-arranged times for satellite communications links through the Tracking and Data Relay Satellite (TDRS). One of the challenges in implementing an on-demand access protocol into the Space Network, is the fact that a low Earth orbiting (LEO) satellite's communications will be subject to a doppler shift which is outside the capability of the NASA ground station to lock onto. In a prearranged system, the satellite's doppler is known a priori, and the ground station is able to lock onto the satellite's signal. This paper describes the development of a high speed analog to digital interface into a Digital Signal Processor (DSP). This system will be used for identifying the doppler shift of a LEO satellite through the Space Network, and aiding the ground station equipment in locking onto the signal. Although this interface is specific to one application, it can be used as a basis for interfacing other devices with a DSP.

Left atrial physiology and pathophysiology: Role of deformation imaging

PubMed Central

Kowallick, Johannes Tammo; Lotz, Joachim; Hasenfuß, Gerd; Schuster, Andreas

2015-01-01

The left atrium (LA) acts as a modulator of left ventricular (LV) filling. Although there is considerable evidence to support the use of LA maximum and minimum volumes for disease prediction, theoretical considerations and a growing body of literature suggest to focus on the quantification of the three basic LA functions: (1) Reservoir function: collection of pulmonary venous return during LV systole; (2) Conduit function: passage of blood to the left ventricle during early LV diastole; and (3) Contractile booster pump function (augmentation of ventricular filling during late LV diastole. Tremendous advances in our ability to non-invasively characterize all three elements of atrial function include speckle tracking echocardiography (STE), and more recently cardiovascular magnetic resonance myocardial feature tracking (CMR-FT). Corresponding imaging biomarkers are increasingly recognized to have incremental roles in determining prognosis and risk stratification in cardiac dysfunction of different origins. The current editorial introduces the role of STE and CMR-FT for the functional assessment of LA deformation as determined by strain and strain rate imaging and provides an outlook of how this exciting field may develop in the future. PMID:26131333

More rapid climate change promotes evolutionary rescue through selection for increased dispersal distance.

PubMed

Boeye, Jeroen; Travis, Justin M J; Stoks, Robby; Bonte, Dries

2013-02-01

Species can either adapt to new conditions induced by climate change or shift their range in an attempt to track optimal environmental conditions. During current range shifts, species are simultaneously confronted with a second major anthropogenic disturbance, landscape fragmentation. Using individual-based models with a shifting climate window, we examine the effect of different rates of climate change on the evolution of dispersal distances through changes in the genetically determined dispersal kernel. Our results demonstrate that the rate of climate change is positively correlated to the evolved dispersal distances although too fast climate change causes the population to crash. When faced with realistic rates of climate change, greater dispersal distances evolve than those required for the population to keep track of the climate, thereby maximizing population size. Importantly, the greater dispersal distances that evolve when climate change is more rapid, induce evolutionary rescue by facilitating the population in crossing large gaps in the landscape. This could ensure population persistence in case of range shifting in fragmented landscapes. Furthermore, we highlight problems in using invasion speed as a proxy for potential range shifting abilities under climate change.

Australia's continental-scale acoustic tracking database and its automated quality control process

NASA Astrophysics Data System (ADS)

Hoenner, Xavier; Huveneers, Charlie; Steckenreuter, Andre; Simpfendorfer, Colin; Tattersall, Katherine; Jaine, Fabrice; Atkins, Natalia; Babcock, Russ; Brodie, Stephanie; Burgess, Jonathan; Campbell, Hamish; Heupel, Michelle; Pasquer, Benedicte; Proctor, Roger; Taylor, Matthew D.; Udyawer, Vinay; Harcourt, Robert

2018-01-01

Our ability to predict species responses to environmental changes relies on accurate records of animal movement patterns. Continental-scale acoustic telemetry networks are increasingly being established worldwide, producing large volumes of information-rich geospatial data. During the last decade, the Integrated Marine Observing System's Animal Tracking Facility (IMOS ATF) established a permanent array of acoustic receivers around Australia. Simultaneously, IMOS developed a centralised national database to foster collaborative research across the user community and quantify individual behaviour across a broad range of taxa. Here we present the database and quality control procedures developed to collate 49.6 million valid detections from 1891 receiving stations. This dataset consists of detections for 3,777 tags deployed on 117 marine species, with distances travelled ranging from a few to thousands of kilometres. Connectivity between regions was only made possible by the joint contribution of IMOS infrastructure and researcher-funded receivers. This dataset constitutes a valuable resource facilitating meta-analysis of animal movement, distributions, and habitat use, and is important for relating species distribution shifts with environmental covariates.

Lissencephaly-1 is a context-dependent regulator of the human dynein complex

PubMed Central

Baumbach, Janina; Murthy, Andal; McClintock, Mark A; Dix, Carly I; Zalyte, Ruta; Hoang, Ha Thi; Bullock, Simon L

2017-01-01

The cytoplasmic dynein-1 (dynein) motor plays a central role in microtubule organisation and cargo transport. These functions are spatially regulated by association of dynein and its accessory complex dynactin with dynamic microtubule plus ends. Here, we elucidate in vitro the roles of dynactin, end-binding protein-1 (EB1) and Lissencephaly-1 (LIS1) in the interaction of end tracking and minus end-directed human dynein complexes with these sites. LIS1 promotes dynactin-dependent tracking of dynein on both growing and shrinking plus ends. LIS1 also increases the frequency and velocity of processive dynein movements that are activated by complex formation with dynactin and a cargo adaptor. This stimulatory effect of LIS1 contrasts sharply with its documented ability to inhibit the activity of isolated dyneins. Collectively, our findings shed light on how mammalian dynein complexes associate with dynamic microtubules and help clarify how LIS1 promotes the plus-end localisation and cargo transport functions of dynein in vivo. DOI: http://dx.doi.org/10.7554/eLife.21768.001 PMID:28406398

Individualization of music-based rhythmic auditory cueing in Parkinson's disease.

PubMed

Bella, Simone Dalla; Dotov, Dobromir; Bardy, Benoît; de Cock, Valérie Cochen

2018-06-04

Gait dysfunctions in Parkinson's disease can be partly relieved by rhythmic auditory cueing. This consists in asking patients to walk with a rhythmic auditory stimulus such as a metronome or music. The effect on gait is visible immediately in terms of increased speed and stride length. Moreover, training programs based on rhythmic cueing can have long-term benefits. The effect of rhythmic cueing, however, varies from one patient to the other. Patients' response to the stimulation may depend on rhythmic abilities, often deteriorating with the disease. Relatively spared abilities to track the beat favor a positive response to rhythmic cueing. On the other hand, most patients with poor rhythmic abilities either do not respond to the cues or experience gait worsening when walking with cues. An individualized approach to rhythmic auditory cueing with music is proposed to cope with this variability in patients' response. This approach calls for using assistive mobile technologies capable of delivering cues that adapt in real time to patients' gait kinematics, thus affording step synchronization to the beat. Individualized rhythmic cueing can provide a safe and cost-effective alternative to standard cueing that patients may want to use in their everyday lives. © 2018 New York Academy of Sciences.

Investigating RFID for Roadside Identification Involving Freight Commercial Vehicle Operators

DOT National Transportation Integrated Search

2010-01-01

Radio Frequency Identification (RFID) is an emerging technology to track commercial vehicles. This transcript describes research that investigates the ability for RFID technologies to work in license plates. Mile markers are common fixtures on the ro...

Modeling, Simulation, and Gaming: Student Capstone Conference

NASA Technical Reports Server (NTRS)

Banks, Catherine

2008-01-01

Highlights student research and student projects focused on MS&G. Competitive presentations - Volunteer judges from industry, government, military and academic institutions across America. - Evaluate research, presentation expertise, . and ability to answer questions. - Judges also facilitate their assigned conference tracks

Spanning the Great Divide between Tenure-Track and Non-Tenure-Track Faculty

ERIC Educational Resources Information Center

Kezar, Adrianna

2012-01-01

In academia, there are two different worlds, one inhabited by tenure-track and the other by non-tenure-track faculty. In the first, people encourage faculty to become involved in a series of important reforms that increase student success, completion, and learning. In this first world, people envision faculty simultaneously increasing their…

At-risk elementary school children with one year of classroom music instruction are better at keeping a beat.

PubMed

Slater, Jessica; Tierney, Adam; Kraus, Nina

2013-01-01

Temporal processing underlies both music and language skills. There is increasing evidence that rhythm abilities track with reading performance and that language disorders such as dyslexia are associated with poor rhythm abilities. However, little is known about how basic time-keeping skills can be shaped by musical training, particularly during critical literacy development years. This study was carried out in collaboration with Harmony Project, a non-profit organization providing free music education to children in the gang reduction zones of Los Angeles. Our findings reveal that elementary school children with just one year of classroom music instruction perform more accurately in a basic finger-tapping task than their untrained peers, providing important evidence that fundamental time-keeping skills may be strengthened by short-term music training. This sets the stage for further examination of how music programs may be used to support the development of basic skills underlying learning and literacy, particularly in at-risk populations which may benefit the most.

Neural basis of the cognitive map: path integration does not require hippocampus or entorhinal cortex.

PubMed

Shrager, Yael; Kirwan, C Brock; Squire, Larry R

2008-08-19

The hippocampus and entorhinal cortex have been linked to both memory functions and to spatial cognition, but it has been unclear how these ideas relate to each other. An important part of spatial cognition is the ability to keep track of a reference location using self-motion cues (sometimes referred to as path integration), and it has been suggested that the hippocampus or entorhinal cortex is essential for this ability. Patients with hippocampal lesions or larger lesions that also included entorhinal cortex were led on paths while blindfolded (up to 15 m in length) and were asked to actively maintain the path in mind. Patients pointed to and estimated their distance from the start location as accurately as controls. A rotation condition confirmed that performance was based on self-motion cues. When demands on long-term memory were increased, patients were impaired. Thus, in humans, the hippocampus and entorhinal cortex are not essential for path integration.

Horizontal cosmic ray muon radiography for imaging nuclear threats

NASA Astrophysics Data System (ADS)

Morris, Christopher L.; Bacon, Jeffrey; Borozdin, Konstantin; Fabritius, Joseph; Miyadera, Haruo; Perry, John; Sugita, Tsukasa

2014-07-01

Muon tomography is a technique that uses information contained in the Coulomb scattering of cosmic ray muons to generate three dimension images of volumes between tracking detectors. Advantages of this technique are the muons ability to penetrate significant overburden and the absence of any additional dose beyond the natural cosmic ray flux. Disadvantages include the long exposure times and limited resolution because of the low flux. Here we compare the times needed to image objects using both vertically and horizontally mounted tracking detectors and we develop a predictive model for other geometries.

Monitoring bruise age using visible diffuse reflectance spectroscopy

NASA Astrophysics Data System (ADS)

McMurdy, John W.; Duffy, Susan; Crawford, Gregory P.

2007-02-01

The ability to determine the age of a bruise of unknown age mechanism is important in matters of domestic and child abuse and forensics. While physicians are asked to make clinical judgment on the age of a bruise using color and tenderness, studies have shown that a physicians estimate is highly inaccurate and in cases no better than chance alone. We present here the temporal progression of reflection spectrum collected from accidentally inflicted contusions in adult and child study participants with a synopsis of the observed phenomena. Reflection spectra collected using a portable fiber optic reflection spectrometer can track the increase in extravasated hemoglobin from trauma caused blood vessel rupture and subsequent removal of this hemoglobin occurring concurrent with an increase in the absorption attributed to the breakdown product bilirubin. We hypothesize that this time dependent pattern can be used to determine the age of an unknown bruise in an individual provided rate constant information for the patient can be determined in a controlled calibration bruise. Using reflection spectra to estimate bruise age can provide a rapid and noninvasive method to improve the ability of physicians in dating the age of a contusion.

Changed processing of visual sexual stimuli under GnRH-therapy--a single case study in pedophilia using eye tracking and fMRI.

PubMed

Jordan, Kirsten; Fromberger, Peter; Laubinger, Helge; Dechent, Peter; Müller, Jürgen L

2014-05-17

Antiandrogen therapy (ADT) has been used for 30 years to treat pedophilic patients. The aim of the treatment is a reduction in sexual drive and, in consequence, a reduced risk of recidivism. Yet the therapeutic success of antiandrogens is uncertain especially regarding recidivism. Meta-analyses and reviews report only moderate and often mutually inconsistent effects. Based on the case of a 47 year old exclusively pedophilic forensic inpatient, we examined the effectiveness of a new eye tracking method and a new functional magnetic resonance imaging (fMRI)-design in regard to the evaluation of ADT in pedophiles. We analyzed the potential of these methods in exploring the impact of ADT on automatic and controlled attentional processes in pedophiles. Eye tracking and fMRI measures were conducted before the initial ADT as well as four months after the onset of ADT. The patient simultaneously viewed an image of a child and an image of an adult while eye movements were measured. During the fMRI-measure the same stimuli were presented subliminally. Eye movements demonstrated that controlled attentional processes change under ADT, whereas automatic processes remained mostly unchanged. We assume that these results reflect either the increased ability of the patient to control his eye movements while viewing prepubertal stimuli or his better ability to manipulate his answer in a socially desirable manner. Unchanged automatic attentional processes could reflect the stable pedophilic preference of the patient. Using fMRI, the subliminal presentation of sexually relevant stimuli led to changed activation patterns under the influence of ADT in occipital and parietal brain regions, the hippocampus, and also in the orbitofrontal cortex. We suggest that even at an unconscious level ADT can lead to changed processing of sexually relevant stimuli, reflecting changes of cognitive and perceptive automatic processes. We are convinced that our experimental designs using eye tracking and fMRI could prospectively add additional and valuable information in the evaluation of ADT in paraphilic patients and sex offenders. But with respect to the limited significance of this single case study, these first results are preliminary and further studies have to be conducted with healthy subjects and patients.

Changed processing of visual sexual stimuli under GnRH-therapy – a single case study in pedophilia using eye tracking and fMRI

PubMed Central

2014-01-01

Background Antiandrogen therapy (ADT) has been used for 30 years to treat pedophilic patients. The aim of the treatment is a reduction in sexual drive and, in consequence, a reduced risk of recidivism. Yet the therapeutic success of antiandrogens is uncertain especially regarding recidivism. Meta-analyses and reviews report only moderate and often mutually inconsistent effects. Case presentation Based on the case of a 47 year old exclusively pedophilic forensic inpatient, we examined the effectiveness of a new eye tracking method and a new functional magnetic resonance imaging (fMRI)-design in regard to the evaluation of ADT in pedophiles. We analyzed the potential of these methods in exploring the impact of ADT on automatic and controlled attentional processes in pedophiles. Eye tracking and fMRI measures were conducted before the initial ADT as well as four months after the onset of ADT. The patient simultaneously viewed an image of a child and an image of an adult while eye movements were measured. During the fMRI-measure the same stimuli were presented subliminally. Eye movements demonstrated that controlled attentional processes change under ADT, whereas automatic processes remained mostly unchanged. We assume that these results reflect either the increased ability of the patient to control his eye movements while viewing prepubertal stimuli or his better ability to manipulate his answer in a socially desirable manner. Unchanged automatic attentional processes could reflect the stable pedophilic preference of the patient. Using fMRI, the subliminal presentation of sexually relevant stimuli led to changed activation patterns under the influence of ADT in occipital and parietal brain regions, the hippocampus, and also in the orbitofrontal cortex. We suggest that even at an unconscious level ADT can lead to changed processing of sexually relevant stimuli, reflecting changes of cognitive and perceptive automatic processes. Conclusion We are convinced that our experimental designs using eye tracking and fMRI could prospectively add additional and valuable information in the evaluation of ADT in paraphilic patients and sex offenders. But with respect to the limited significance of this single case study, these first results are preliminary and further studies have to be conducted with healthy subjects and patients. PMID:24885644

[Research on fuzzy proportional-integral-derivative control of master-slave minimally invasive operation robot driver].

PubMed

Zhao, Ximei; Ren, Chengyi; Liu, Hao; Li, Haogyi

2014-12-01

Robotic catheter minimally invasive operation requires that the driver control system has the advantages of quick response, strong anti-jamming and real-time tracking of target trajectory. Since the catheter parameters of itself and movement environment and other factors continuously change, when the driver is controlled using traditional proportional-integral-derivative (PID), the controller gain becomes fixed once the PID parameters are set. It can not change with the change of the parameters of the object and environmental disturbance so that its change affects the position tracking accuracy, and may bring a large overshoot endangering patients' vessel. Therefore, this paper adopts fuzzy PID control method to adjust PID gain parameters in the tracking process in order to improve the system anti-interference ability, dynamic performance and tracking accuracy. The simulation results showed that the fuzzy PID control method had a fast tracking performance and a strong robustness. Compared with those of traditional PID control, the feasibility and practicability of fuzzy PID control are verified in a robotic catheter minimally invasive operation.

Real-time subpixel-accuracy tracking of single mitochondria in neurons reveals heterogeneous mitochondrial motion.

PubMed

Alsina, Adolfo; Lai, Wu Ming; Wong, Wai Kin; Qin, Xianan; Zhang, Min; Park, Hyokeun

2017-11-04

Mitochondria are essential for cellular survival and function. In neurons, mitochondria are transported to various subcellular regions as needed. Thus, defects in the axonal transport of mitochondria are related to the pathogenesis of neurodegenerative diseases, and the movement of mitochondria has been the subject of intense research. However, the inability to accurately track mitochondria with subpixel accuracy has hindered this research. Here, we report an automated method for tracking mitochondria based on the center of fluorescence. This tracking method, which is accurate to approximately one-tenth of a pixel, uses the centroid of an individual mitochondrion and provides information regarding the distance traveled between consecutive imaging frames, instantaneous speed, net distance traveled, and average speed. Importantly, this new tracking method enables researchers to observe both directed motion and undirected movement (i.e., in which the mitochondrion moves randomly within a small region, following a sub-diffusive motion). This method significantly improves our ability to analyze the movement of mitochondria and sheds light on the dynamic features of mitochondrial movement. Copyright © 2017 Elsevier Inc. All rights reserved.

Precise Head Tracking in Hearing Applications

NASA Astrophysics Data System (ADS)

Helle, A. M.; Pilinski, J.; Luhmann, T.

2015-05-01

The paper gives an overview about two research projects, both dealing with optical head tracking in hearing applications. As part of the project "Development of a real-time low-cost tracking system for medical and audiological problems (ELCoT)" a cost-effective single camera 3D tracking system has been developed which enables the detection of arm and head movements of human patients. Amongst others, the measuring system is designed for a new hearing test (based on the "Mainzer Kindertisch"), which analyzes the directional hearing capabilities of children in cooperation with the research project ERKI (Evaluation of acoustic sound source localization for children). As part of the research project framework "Hearing in everyday life (HALLO)" a stereo tracking system is being used for analyzing the head movement of human patients during complex acoustic events. Together with the consideration of biosignals like skin conductance the speech comprehension and listening effort of persons with reduced hearing ability, especially in situations with background noise, is evaluated. For both projects the system design, accuracy aspects and results of practical tests are discussed.

In-flight wind identification and soft landing control for autonomous unmanned powered parafoils

NASA Astrophysics Data System (ADS)

Luo, Shuzhen; Tan, Panlong; Sun, Qinglin; Wu, Wannan; Luo, Haowen; Chen, Zengqiang

2018-04-01

For autonomous unmanned powered parafoil, the ability to perform a final flare manoeuvre against the wind direction can allow a considerable reduction of horizontal and vertical velocities at impact, enabling a soft landing for a safe delivery of sensible loads; the lack of knowledge about the surface-layer winds will result in messing up terminal flare manoeuvre. Moreover, unknown or erroneous winds can also prevent the parafoil system from reaching the target area. To realize accurate trajectory tracking and terminal soft landing in the unknown wind environment, an efficient in-flight wind identification method merely using Global Positioning System (GPS) data and recursive least square method is proposed to online identify the variable wind information. Furthermore, a novel linear extended state observation filter is proposed to filter the groundspeed of the powered parafoil system calculated by the GPS information to provide a best estimation of the present wind during flight. Simulation experiments and real airdrop tests demonstrate the great ability of this method to in-flight identify the variable wind field, and it can benefit the powered parafoil system to fulfil accurate tracking control and a soft landing in the unknown wind field with high landing accuracy and strong wind-resistance ability.

Low-Cost Robotic Assessment of Visuo-Motor Deficits in Alzheimer's Disease.

PubMed

Bartoli, Eleonora; Caso, Francesca; Magnani, Giuseppe; Baud-Bovy, Gabriel

2017-07-01

A low-cost robotic interface was used to assess the visuo-motor performance of patients with Alzheimer's disease (AD). Twenty AD patients and twenty age-matched controls participated in this work. The battery of tests included simple reaction times, position tracking, and stabilization tasks performed with both hands. The regularity, velocity, visual and haptic feedback were manipulated to vary movement complexity. Reaction times and movement tracking error were analyzed. Results show a marked group effect on a subset of conditions, in particular when the patients could not rely on the visual feedback of hand movement. The visuo-motor performance correlated with the measures of global cognitive functioning and with different memory-related abilities. Our results support the hypothesis that the ability to recall and use visuo-spatial associations might underlie the impairment in complex motor behavior that has been reported in AD patients. Importantly, the patients had preserved learning effects across sessions, which might relate to visuo-motor deficits being less evident in every-day life and clinical assessments. This robotic assessment, lasting less than 1 h, provides detailed information about the integrity of visuo-motor abilities. The data can aid the understanding of the complex pattern of deficits that characterizes this pervasive disease.

Neural responses to sounds presented on and off the beat of ecologically valid music

PubMed Central

Tierney, Adam; Kraus, Nina

2013-01-01

The tracking of rhythmic structure is a vital component of speech and music perception. It is known that sequences of identical sounds can give rise to the percept of alternating strong and weak sounds, and that this percept is linked to enhanced cortical and oscillatory responses. The neural correlates of the perception of rhythm elicited by ecologically valid, complex stimuli, however, remain unexplored. Here we report the effects of a stimulus' alignment with the beat on the brain's processing of sound. Human subjects listened to short popular music pieces while simultaneously hearing a target sound. Cortical and brainstem electrophysiological onset responses to the sound were enhanced when it was presented on the beat of the music, as opposed to shifted away from it. Moreover, the size of the effect of alignment with the beat on the cortical response correlated strongly with the ability to tap to a beat, suggesting that the ability to synchronize to the beat of simple isochronous stimuli and the ability to track the beat of complex, ecologically valid stimuli may rely on overlapping neural resources. These results suggest that the perception of musical rhythm may have robust effects on processing throughout the auditory system. PMID:23717268

Seal Whiskers Vibrate Over Broad Frequencies During Hydrodynamic Tracking.

PubMed

Murphy, Christin T; Reichmuth, Colleen; Eberhardt, William C; Calhoun, Benton H; Mann, David A

2017-08-21

Although it is known that seals can use their whiskers (vibrissae) to extract relevant information from complex underwater flow fields, the underlying functioning of the system and the signals received by the sensors are poorly understood. Here we show that the vibrations of seal whiskers may provide information about hydrodynamic events and enable the sophisticated wake-tracking abilities of these animals. We developed a miniature accelerometer tag to study seal whisker movement in situ. We tested the ability of the tag to measure vibration in excised whiskers in a flume in response to laminar flow and disturbed flow. We then trained a seal to wear the tag and follow an underwater hydrodynamic trail to measure the whisker signals available to the seal. The results showed that whiskers vibrated at frequencies of 100-300 Hz, with a dynamic response. These measurements are the first to capture the incoming signals received by the vibrissae of a live seal and show that there are prominent signals at frequencies where the seal tactogram shows good sensitivity. Tapping into the mechanoreceptive interface between the animal and the environment may help to decipher the functional basis of this extraordinary hydrodynamic detection ability.

The Emergent Properties of Conspecific Attraction Can Limit a Species' Ability to Track Environmental Change.

PubMed

Stodola, Kirk W; Ward, Michael P

2017-06-01

Multiple biotic, abiotic, and evolutionary constraints interact to determine a species' range. However, most species are not present in all suitable and accessible locations. Dispersal ability may explain why many species do not occupy all suitable habitat, but highly mobile species also exhibit a mismatch. Habitat selection behavior where individuals are site faithful and settle near conspecifics could create a social pressure that make a species' geographic range resistant to change. We investigated this possibility by using an individual-based model of habitat selection where habitat quality moved each year. Our model demonstrated the benefits of conspecific attraction in relatively stable environments and its detrimental influence when habitat quality shifted rapidly. These results were most apparent when adult survival was high, because site fidelity led to more individuals occupying poor-quality habitat areas as habitat quality changed. These individuals attracted other dispersing individuals, thereby decreasing the ability to track shifts in habitat quality, which we refer to as "social inertia." Consequently, social inertia may arise for species that exhibit site fidelity and conspecific attraction, which may have conservation implications in light of climate change and widespread alteration of natural habitats.

An eye-tracking controlled neuropsychological battery for cognitive assessment in neurological diseases.

PubMed

Poletti, Barbara; Carelli, Laura; Solca, Federica; Lafronza, Annalisa; Pedroli, Elisa; Faini, Andrea; Zago, Stefano; Ticozzi, Nicola; Ciammola, Andrea; Morelli, Claudia; Meriggi, Paolo; Cipresso, Pietro; Lulé, Dorothée; Ludolph, Albert C; Riva, Giuseppe; Silani, Vincenzo

2017-04-01

Traditional cognitive assessment in neurological conditions involving physical disability is often prevented by the presence of verbal-motor impairment; to date, an extensive motor-verbal-free neuropsychological battery is not available for such purposes. We adapted a set of neuropsychological tests, assessing language, attentional abilities, executive functions and social cognition, for eye-tracking (ET) control, and explored its feasibility in a sample of healthy participants. Thirty healthy subjects performed a neuropsychological assessment, using an ET-based neuropsychological battery, together with standard "paper and pencil" cognitive measures for frontal (Frontal Assessment Battery-FAB) and working memory abilities (Digit Sequencing Task) and for global cognitive efficiency (Montreal Cognitive Assessment-MoCA). Psychological measures of anxiety (State-Trait Anxiety Inventory-Y-STAI-Y) and depression (Beck Depression Inventory-BDI) were also collected, and a usability questionnaire was administered. Significant correlations were observed between the "paper and pencil" screening of working memory abilities and the ET-based neuropsychological measures. The ET-based battery also correlated with the MoCA, while poor correlations were observed with the FAB. Usability aspects were found to be influenced by both working memory abilities and psychological components. The ET-based neuropsychological battery developed could provide an extensive assessment of cognitive functions, allowing participants to perform tasks independently from the integrity of motor or verbal channels. Further studies will be aimed at investigating validity and usability components in neurological populations with motor-verbal impairments.

BIOMARKER LIPIDS IN RED TIDE (GYMNODINIUM BREVE) BLOOMS ALONG THE NORTHWEST FLORIDA COAST

EPA Science Inventory

The ability to characterize phytoplankton communities and algal blooms using lipids as biomarkers requires knowledge of their distribution and taxonomic significance. Such an approach would have application, for example, in distinguishing and tracking certain dinoflagellates suc...

Idaho out-of-service verification field operational test

DOT National Transportation Integrated Search

2000-02-01

The Out-of-Service Verification Field Operational Test Project was initiated in 1994. The purpose of the project was to test the feasibility of using sensors and a computerized tracking system to augment the ability of inspectors to monitor and contr...

The Potential Utility of Eye Movements in the Detection and Characterization of Everyday Functional Difficulties in Mild Cognitive Impairment.

PubMed

Seligman, Sarah C; Giovannetti, Tania

2015-06-01

Mild cognitive impairment (MCI) refers to the intermediate period between the typical cognitive decline of normal aging and more severe decline associated with dementia, and it is associated with greater risk for progression to dementia. Research has suggested that functional abilities are compromised in MCI, but the degree of impairment and underlying mechanisms remain poorly understood. The development of sensitive measures to assess subtle functional decline poses a major challenge for characterizing functional limitations in MCI. Eye-tracking methodology has been used to describe visual processes in everyday, naturalistic action among healthy older adults as well as several case studies of severely impaired individuals, and it has successfully differentiated healthy older adults from those with MCI on specific visual tasks. These studies highlight the promise of eye-tracking technology as a method to characterize subtle functional decline in MCI. However, to date no studies have examined visual behaviors during completion of naturalistic tasks in MCI. This review describes the current understanding of functional ability in MCI, summarizes findings of eye-tracking studies in healthy individuals, severe impairment, and MCI, and presents future research directions to aid with early identification and prevention of functional decline in disorders of aging.

Development of Multifunctional Magnetic Nanoparticles for Genetic Engineering and Tracking of Neural Stem Cells.

PubMed

Adams, Christopher; Israel, Liron Limor; Ostrovsky, Stella; Taylor, Arthur; Poptani, Harish; Lellouche, Jean-Paul; Chari, Divya

2016-04-06

Genetic modification of cell transplant populations and cell tracking ability are key underpinnings for effective cell therapies. Current strategies to achieve these goals utilize methods which are unsuitable for clinical translation because of related safety issues, and multiple protocol steps adding to cost and complexity. Multifunctional magnetic nanoparticles (MNPs) offering dual mode gene delivery and imaging contrast capacity offer a valuable tool in this context. Despite their key benefits, there is a critical lack of neurocompatible and multifunctional particles described for use with transplant populations for neurological applications. Here, a systematic screen of MNPs (using a core shown to cause contrast in magnetic resonance imaging (MRI)) bearing various surface chemistries (polyethylenimine (PEI) and oxidized PEI and hybrids of oxidized PEI/alginic acid, PEI/chitosan and PEI/polyamidoamine) is performed to test their ability to genetically engineer neural stem cells (NSCs; a cell population of high clinical relevance for central nervous system disorders). It is demonstrated that gene delivery to NSCs can be safely achieved using two of the developed formulations (PEI and oxPEI/alginic acid) when used in conjunction with oscillating magnetofection technology. After transfection, intracellular particles can be detected by histological procedures with labeled cells displaying contrast in MRI (for real time cell tracking). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Career Development Support in Pediatric Critical Care Medicine: A National Survey of Fellows and Junior Faculty.

PubMed

Cifra, Christina L; Balikai, Shilpa S; Murtha, Tanya D; Hsu, Benson; Riley, Carley L

2017-04-01

To determine the perceptions of current pediatric critical care medicine fellows and junior faculty regarding the extent and quality of career development support received during fellowship training. Web-based cross-sectional survey open from September to November 2015. Accreditation Council for Graduate Medical Education-accredited pediatric critical care medicine fellowship programs. Pediatric critical care medicine fellows (second yr or higher) and junior faculty (within 5 yr of completing a pediatric critical care medicine fellowship program). None. There were 129 respondents to the survey, representing 63% of Accreditation Council for Graduate Medical Education-accredited pediatric critical care medicine fellowship programs. Respondents were evenly divided between fellows and junior faculty. Nearly, half (49%) of respondents reported that their pediatric critical care medicine fellowship program provided a formal career development curriculum. Ideal career tracks chosen included academic clinician educator (64%), physician-scientist (27%), community-based (nonacademic) clinician (11%), and administrator (11%). There was a disparity in focused career development support provided by programs, with a minority providing good support for those pursuing a community-based clinician track (32%) or administrator track (16%). Only 43% of fellows perceived that they have a good chance of obtaining their ideal pediatric critical care medicine position, with the most common perceived barrier being increased competition for limited job opportunities. Most respondents expressed interest in a program specific to pediatric critical care medicine career development that is sponsored by a national professional organization. Most pediatric critical care medicine fellows and junior faculty reported good to excellent career development support during fellowship. However, important gaps remain, particularly for those pursuing community-based (nonacademic) and administrative tracks. Fellows were uncertain regarding future pediatric critical care medicine employment and their ability to pursue ideal career tracks. There may be a role for professional organizations to provide additional resources for career development in pediatric critical care medicine.

Position Affects Performance in Multiple-Object Tracking in Rugby Union Players

PubMed Central

Martín, Andrés; Sfer, Ana M.; D'Urso Villar, Marcela A.; Barraza, José F.

2017-01-01

We report an experiment that examines the performance of rugby union players and a control group composed of graduate student with no sport experience, in a multiple-object tracking task. It compares the ability of 86 high level rugby union players grouped as Backs and Forwards and the control group, to track a subset of randomly moving targets amongst the same number of distractors. Several difficulties were included in the experimental design in order to evaluate possible interactions between the relevant variables. Results show that the performance of the Backs is better than that of the other groups, but the occurrence of interactions precludes an isolated groups analysis. We interpret the results within the framework of visual attention and discuss both, the implications of our results and the practical consequences. PMID:28951725

Tracking of Cells with a Compact Microscope Imaging System with Intelligent Controls

NASA Technical Reports Server (NTRS)

McDowell, Mark (Inventor)

2007-01-01

A Microscope Imaging System (CMIS) with intelligent controls is disclosed that provides techniques for scanning, identifying, detecting and tracking microscopic changes in selected characteristics or features of various surfaces including, but not limited to, cells, spheres, and manufactured products subject to difficult-to-see imperfections. The practice of the present invention provides applications that include colloidal hard spheres experiments, biological cell detection for patch clamping, cell movement and tracking, as well as defect identification in products, such as semiconductor devices, where surface damage can be significant, but difficult to detect. The CMIS system is a machine vision system, which combines intelligent image processing with remote control capabilities and provides the ability to autofocus on a microscope sample, automatically scan an image, and perform machine vision analysis on multiple samples simultaneously

Tracking of cells with a compact microscope imaging system with intelligent controls

NASA Technical Reports Server (NTRS)

McDowell, Mark (Inventor)

2007-01-01

A Microscope Imaging System (CMIS) with intelligent controls is disclosed that provides techniques for scanning, identifying, detecting and tracking microscopic changes in selected characteristics or features of various surfaces including, but not limited to, cells, spheres, and manufactured products subject to difficult-to-see imperfections. The practice of the present invention provides applications that include colloidal hard spheres experiments, biological cell detection for patch clamping, cell movement and tracking, as well as defect identification in products, such as semiconductor devices, where surface damage can be significant, but difficult to detect. The CMIS system is a machine vision system, which combines intelligent image processing with remote control capabilities and provides the ability to auto-focus on a microscope sample, automatically scan an image, and perform machine vision analysis on multiple samples simultaneously.

A real-time optical tracking and measurement processing system for flying targets.

PubMed

Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

2014-01-01

Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control.

Robust guaranteed cost tracking control of quadrotor UAV with uncertainties.

PubMed

Xu, Zhiwei; Nian, Xiaohong; Wang, Haibo; Chen, Yinsheng

2017-07-01

In this paper, a robust guaranteed cost controller (RGCC) is proposed for quadrotor UAV system with uncertainties to address set-point tracking problem. A sufficient condition of the existence for RGCC is derived by Lyapunov stability theorem. The designed RGCC not only guarantees the whole closed-loop system asymptotically stable but also makes the quadratic performance level built for the closed-loop system have an upper bound irrespective to all admissible parameter uncertainties. Then, an optimal robust guaranteed cost controller is developed to minimize the upper bound of performance level. Simulation results verify the presented control algorithms possess small overshoot and short setting time, with which the quadrotor has ability to perform set-point tracking task well. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

A Real-Time Optical Tracking and Measurement Processing System for Flying Targets

PubMed Central

Guo, Pengyu; Ding, Shaowen; Zhang, Hongliang; Zhang, Xiaohu

2014-01-01

Optical tracking and measurement for flying targets is unlike the close range photography under a controllable observation environment, which brings extreme conditions like diverse target changes as a result of high maneuver ability and long cruising range. This paper first designed and realized a distributed image interpretation and measurement processing system to achieve resource centralized management, multisite simultaneous interpretation and adaptive estimation algorithm selection; then proposed a real-time interpretation method which contains automatic foreground detection, online target tracking, multiple features location, and human guidance. An experiment is carried out at performance and efficiency evaluation of the method by semisynthetic video. The system can be used in the field of aerospace tests like target analysis including dynamic parameter, transient states, and optical physics characteristics, with security control. PMID:24987748

Fitness declines towards range limits and local adaptation to climate affect dispersal evolution during climate-induced range shifts.

PubMed

Hargreaves, A L; Bailey, S F; Laird, R A

2015-08-01

Dispersal ability will largely determine whether species track their climatic niches during climate change, a process especially important for populations at contracting (low-latitude/low-elevation) range limits that otherwise risk extinction. We investigate whether dispersal evolution at contracting range limits is facilitated by two processes that potentially enable edge populations to experience and adjust to the effects of climate deterioration before they cause extinction: (i) climate-induced fitness declines towards range limits and (ii) local adaptation to a shifting climate gradient. We simulate a species distributed continuously along a temperature gradient using a spatially explicit, individual-based model. We compare range-wide dispersal evolution during climate stability vs. directional climate change, with uniform fitness vs. fitness that declines towards range limits (RLs), and for a single climate genotype vs. multiple genotypes locally adapted to temperature. During climate stability, dispersal decreased towards RLs when fitness was uniform, but increased when fitness declined towards RLs, due to highly dispersive genotypes maintaining sink populations at RLs, increased kin selection in smaller populations, and an emergent fitness asymmetry that favoured dispersal in low-quality habitat. However, this initial dispersal advantage at low-fitness RLs did not facilitate climate tracking, as it was outweighed by an increased probability of extinction. Locally adapted genotypes benefited from staying close to their climate optima; this selected against dispersal under stable climates but for increased dispersal throughout shifting ranges, compared to cases without local adaptation. Dispersal increased at expanding RLs in most scenarios, but only increased at the range centre and contracting RLs given local adaptation to climate. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Evidence for social working memory from a parametric functional MRI study.

PubMed

Meyer, Meghan L; Spunt, Robert P; Berkman, Elliot T; Taylor, Shelley E; Lieberman, Matthew D

2012-02-07

Keeping track of various amounts of social cognitive information, including people's mental states, traits, and relationships, is fundamental to navigating social interactions. However, to date, no research has examined which brain regions support variable amounts of social information processing ("social load"). We developed a social working memory paradigm to examine the brain networks sensitive to social load. Two networks showed linear increases in activation as a function of increasing social load: the medial frontoparietal regions implicated in social cognition and the lateral frontoparietal system implicated in nonsocial forms of working memory. Of these networks, only load-dependent medial frontoparietal activity was associated with individual differences in social cognitive ability (trait perspective-taking). Although past studies of nonsocial load have uniformly found medial frontoparietal activity decreases with increasing task demands, the current study demonstrates these regions do support increasing mental effort when such effort engages social cognition. Implications for the etiology of clinical disorders that implicate social functioning and potential interventions are discussed.

Intelligent neonatal monitoring based on a virtual thermal sensor

PubMed Central

2014-01-01

Background Temperature measurement is a vital part of daily neonatal care. Accurate measurements are important for detecting deviations from normal values for both optimal incubator and radiant warmer functioning. The purpose of monitoring the temperature is to maintain the infant in a thermoneutral environmental zone. This physiological zone is defined as the narrow range of environmental temperatures in which the infant maintains a normal body temperature without increasing his or her metabolic rate and thus oxygen consumption. Although the temperature measurement gold standard is the skin electrode, infrared thermography (IRT) should be considered as an effortless and reliable tool for measuring and mapping human skin temperature distribution and assist in assessing thermoregulatory reflexes. Methods Body surface temperature was recorded under several clinical conditions using an infrared thermography imaging technique. Temperature distributions were recorded as real-time video, which was analyzed to evaluate mean skin temperatures. Emissivity variations were considered for optimal neonatal IRT correction for which the compensation vector was overlaid on the tracking algorithm to improve the temperature reading. Finally, a tracking algorithm was designed for active follow-up of the defined region of interest over a neonate’s geometry. Results The outcomes obtained from the thermal virtual sensor demonstrate its ability to accurately track different geometric profiles and shapes over the external anatomy of a neonate. Only a small percentage of the motion detection attempts failed to fit tracking scenarios due to the lack of a properly matching matrix for the ROI profile over neonate’s body surface. Conclusions This paper presents the design and implementation of a virtual temperature sensing application that can assist neonatologists in interpreting a neonate’s skin temperature patterns. Regarding the surface temperature, the influence of different environmental conditions inside the incubator has been confirming. PMID:24580961

Intelligent neonatal monitoring based on a virtual thermal sensor.

PubMed

Abbas, Abbas K; Leonhardt, Steffen

2014-03-02

Temperature measurement is a vital part of daily neonatal care. Accurate measurements are important for detecting deviations from normal values for both optimal incubator and radiant warmer functioning. The purpose of monitoring the temperature is to maintain the infant in a thermoneutral environmental zone. This physiological zone is defined as the narrow range of environmental temperatures in which the infant maintains a normal body temperature without increasing his or her metabolic rate and thus oxygen consumption. Although the temperature measurement gold standard is the skin electrode, infrared thermography (IRT) should be considered as an effortless and reliable tool for measuring and mapping human skin temperature distribution and assist in assessing thermoregulatory reflexes. Body surface temperature was recorded under several clinical conditions using an infrared thermography imaging technique. Temperature distributions were recorded as real-time video, which was analyzed to evaluate mean skin temperatures. Emissivity variations were considered for optimal neonatal IRT correction for which the compensation vector was overlaid on the tracking algorithm to improve the temperature reading. Finally, a tracking algorithm was designed for active follow-up of the defined region of interest over a neonate's geometry. The outcomes obtained from the thermal virtual sensor demonstrate its ability to accurately track different geometric profiles and shapes over the external anatomy of a neonate. Only a small percentage of the motion detection attempts failed to fit tracking scenarios due to the lack of a properly matching matrix for the ROI profile over neonate's body surface. This paper presents the design and implementation of a virtual temperature sensing application that can assist neonatologists in interpreting a neonate's skin temperature patterns. Regarding the surface temperature, the influence of different environmental conditions inside the incubator has been confirming.

Objective assessment of operator performance during ultrasound-guided procedures.

PubMed

Tabriz, David M; Street, Mandie; Pilgram, Thomas K; Duncan, James R

2011-09-01

Simulation permits objective assessment of operator performance in a controlled and safe environment. Image-guided procedures often require accurate needle placement, and we designed a system to monitor how ultrasound guidance is used to monitor needle advancement toward a target. The results were correlated with other estimates of operator skill. The simulator consisted of a tissue phantom, ultrasound unit, and electromagnetic tracking system. Operators were asked to guide a needle toward a visible point target. Performance was video-recorded and synchronized with the electromagnetic tracking data. A series of algorithms based on motor control theory and human information processing were used to convert raw tracking data into different performance indices. Scoring algorithms converted the tracking data into efficiency, quality, task difficulty, and targeting scores that were aggregated to create performance indices. After initial feasibility testing, a standardized assessment was developed. Operators (N = 12) with a broad spectrum of skill and experience were enrolled and tested. Overall scores were based on performance during ten simulated procedures. Prior clinical experience was used to independently estimate operator skill. When summed, the performance indices correlated well with estimated skill. Operators with minimal or no prior experience scored markedly lower than experienced operators. The overall score tended to increase according to operator's clinical experience. Operator experience was linked to decreased variation in multiple aspects of performance. The aggregated results of multiple trials provided the best correlation between estimated skill and performance. A metric for the operator's ability to maintain the needle aimed at the target discriminated between operators with different levels of experience. This study used a highly focused task model, standardized assessment, and objective data analysis to assess performance during simulated ultrasound-guided needle placement. The performance indices were closely related to operator experience.

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.

Nanoelectronics enabled chronic multimodal neural platform in a mouse ischemic model

PubMed Central

Luan, Lan; Sullender, Colin T.; Li, Xue; Zhao, Zhengtuo; Zhu, Hanlin; Wei, Xiaoling; Xie, Chong; Dunn, Andrew K.

2018-01-01

Background Despite significant advancements of optical imaging techniques for mapping hemodynamics in small animal models, it remains challenging to combine imaging with spatially resolved electrical recording of individual neurons especially for longitudinal studies. This is largely due to the strong invasiveness to the living brain from the penetrating electrodes and their limited compatibility with longitudinal imaging. New Method We implant arrays of ultraflexible nanoelectronic threads (NETs) in mice for neural recording both at the brain surface and intracortically, which maintain great tissue compatibility chronically. By mounting a cranial window atop of the NET arrays that allows for chronic optical access, we establish a multimodal platform that combines spatially resolved electrical recording of neural activity and laser speckle contrast imaging (LSCI) of cerebral blood flow (CBF) for longitudinal studies. Results We induce peri-infarct depolarizations (PIDs) by targeted photothrombosis, and show the ability to detect its occurrence and propagation through spatiotemporal variations in both extracellular potentials and CBF. We also demonstrate chronic tracking of single-unit neural activity and CBF over days after photothrombosis, from which we observe reperfusion and increased firing rates. Comparison with Existing Method(s) This multimodal platform enables simultaneous mapping of neural activity and hemodynamic parameters at the microscale for quantitative, longitudinal comparisons with minimal perturbation to the baseline neurophysiology. Conclusion The ability to spatiotemporally resolve and chronically track CBF and neural electrical activity in the same living brain region has broad applications for studying the interplay between neural and hemodynamic responses in health and in cerebrovascular and neurological pathologies. PMID:29203409

Dynamic, continuous multitasking training leads to task-specific improvements but does not transfer across action selection tasks

NASA Astrophysics Data System (ADS)

Bender, Angela D.; Filmer, Hannah L.; Naughtin, Claire K.; Dux, Paul E.

2017-12-01

The ability to perform multiple tasks concurrently is an ever-increasing requirement in our information-rich world. Despite this, multitasking typically compromises performance due to the processing limitations associated with cognitive control and decision-making. While intensive dual-task training is known to improve multitasking performance, only limited evidence suggests that training-related performance benefits can transfer to untrained tasks that share overlapping processes. In the real world, however, coordinating and selecting several responses within close temporal proximity will often occur in high-interference environments. Over the last decade, there have been notable reports that training on video action games that require dynamic multitasking in a demanding environment can lead to transfer effects on aspects of cognition such as attention and working memory. Here, we asked whether continuous and dynamic multitasking training extends benefits to tasks that are theoretically related to the trained tasks. To examine this issue, we asked a group of participants to train on a combined continuous visuomotor tracking task and a perceptual discrimination task for six sessions, while an active control group practiced the component tasks in isolation. A battery of tests measuring response selection, response inhibition, and spatial attention was administered before and immediately after training to investigate transfer. Multitasking training resulted in substantial, task-specific gains in dual-task ability, but there was no evidence that these benefits generalized to other action control tasks. The findings suggest that training on a combined visuomotor tracking and discrimination task results in task-specific benefits but provides no additional value for untrained action selection tasks.

WiFi RFID demonstration for resource tracking in a statewide disaster drill.

PubMed

Cole, Stacey L; Siddiqui, Javeed; Harry, David J; Sandrock, Christian E

2011-01-01

To investigate the capabilities of Radio Frequency Identification (RFID) tracking of patients and medical equipment during a simulated disaster response scenario. RFID infrastructure was deployed at two small rural hospitals, in one large academic medical center and in two vehicles. Several item types from the mutual aid equipment list were selected for tracking during the demonstration. A central database server was installed at the UC Davis Medical Center (UCDMC) that collected RFID information from all constituent sites. The system was tested during a statewide disaster drill. During the drill, volunteers at UCDMC were selected to locate assets using the traditional method of locating resources and then using the RFID system. This study demonstrated the effectiveness of RFID infrastructure in real-time resource identification and tracking. Volunteers at UCDMC were able to locate assets substantially faster using RFID, demonstrating that real-time geolocation can be substantially more efficient and accurate than traditional manual methods. A mobile, Global Positioning System (GPS)-enabled RFID system was installed in a pediatric ambulance and connected to the central RFID database via secure cellular communication. This system is unique in that it provides for seamless region-wide tracking that adaptively uses and seamlessly integrates both outdoor cellular-based mobile tracking and indoor WiFi-based tracking. RFID tracking can provide a real-time picture of the medical situation across medical facilities and other critical locations, leading to a more coordinated deployment of resources. The RFID system deployed during this study demonstrated the potential to improve the ability to locate and track victims, healthcare professionals, and medical equipment during a region-wide disaster.

A novel optical investigation technique for railroad track inspection and assessment

NASA Astrophysics Data System (ADS)

Sabato, Alessandro; Beale, Christopher H.; Niezrecki, Christopher

2017-04-01

Track failures due to cross tie degradation or loss in ballast support may result in a number of problems ranging from simple service interruptions to derailments. Structural Health Monitoring (SHM) of railway track is important for safety reasons and to reduce downtime and maintenance costs. For this reason, novel and cost-effective track inspection technologies for assessing tracks' health are currently insufficient and needed. Advancements achieved in recent years in cameras technology, optical sensors, and image-processing algorithms have made machine vision, Structure from Motion (SfM), and three-dimensional (3D) Digital Image Correlation (DIC) systems extremely appealing techniques for extracting structural deformations and geometry profiles. Therefore, optically based, non-contact measurement techniques may be used for assessing surface defects, rail and tie deflection profiles, and ballast condition. In this study, the design of two camera-based measurement systems is proposed for crossties-ballast condition assessment and track examination purposes. The first one consists of four pairs of cameras installed on the underside of a rail car to detect the induced deformation and displacement on the whole length of the track's cross tie using 3D DIC measurement techniques. The second consists of another set of cameras using SfM techniques for obtaining a 3D rendering of the infrastructure from a series of two-dimensional (2D) images to evaluate the state of the track qualitatively. The feasibility of the proposed optical systems is evaluated through extensive laboratory tests, demonstrating their ability to measure parameters of interest (e.g. crosstie's full-field displacement, vertical deflection, shape, etc.) for assessment and SHM of railroad track.

U.S. Marine Corps Training Modeling and Simulation Master Plan

DTIC Science & Technology

2007-01-18

is needed that is not restricted by line of sight (LOS) and is transportable/ deployable. • The LVC-TE must have the ability to have Human Anatomy Motion... Human Anatomy Motion-Tracking and Display HEAT.............................HMMWV Egress Assistance Trainer HLA

An investigation of time-sharing ability as a factor in complex performance.

DOT National Transportation Integrated Search

1976-05-01

Thirty-nine men were tested on a total of six tasks; performance was measured on each task presented individually and on two complex tasks made up of three-task subsets. The tasks measured monitoring, arithmetic, pattern-discrimination, tracking, and...

Strabismus and Amblyopia.

ERIC Educational Resources Information Center

Trief, E.; Morse, A. R.

1988-01-01

Strabismus and amblyopia are two common childhood vision conditions requiring early identification and treatment. Screening devices include external examination of the eye, ability to track, a cover test, acuity tests, and stereoscopic tests. Treatment includes patching therapy, use of glasses, orthoptics, CAM vision stimulator, or a combination…

Waste Information Management System v. 1.0

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bustamante, David G.; Schade, A. Carl

WIMS is a functional interface to an Oracle database for managing the required regulatory information about the handling of Hazardous Waste. WIMS does not have a component to track Radiological Waste data. And it does not have the ability to manage sensitive information.

TScan : stationary LiDAR for traffic and safety studies : object detection and tracking.

DOT National Transportation Integrated Search

2016-08-01

The ability to accurately measure and cost-effectively collect traffic data at road intersections is needed to improve their safety and operations. This study investigates the feasibility of using laser ranging technology (LiDAR) for this purpose. Th...

Single particle tracking with sterol modulation reveals the cholesterol-mediated diffusion properties of integrin receptors.

PubMed

Arora, Neha; Syed, Aleem; Sander, Suzanne; Smith, Emily A

2014-10-07

A combination of sterol modulation with cyclodextrins plus fluorescence microscopy revealed a biophysical mechanism behind cholesterol's influence on the diffusion of a ubiquitous class of receptors called integrins. The heterogeneous diffusion of integrins bound to ligand-coated quantum dots was measured using single particle tracking (SPT), and the ensemble changes in integrin diffusion were measured by fluorescence recovery after photobleaching (FRAP). A 25 ± 1% reduction of membrane cholesterol resulted in three significant changes to the diffusion of ligand-bound αPS2CβPS integrins as measured by SPT. There was a 23% increase in ligand-bound mobile integrins; there was a statistically significant increase in the average diffusion coefficient inside zones of confined diffusion, and histograms of confined integrin trajectories showed an increased frequency in the range of 0.1-1 μm(2) s(-1) and a decreased frequency in the 0.001-0.1 μm(2) s(-1) range. No statistical change was measured in the duration of confinement nor the size of confined zones. Restoring the cholesterol-depleted cells with exogenous cholesterol or exogenous epicholesterol resulted in similar diffusion properties. Epicholesterol differs from cholesterol in the orientation of a single hydroxyl group. The ability of epicholesterol to substitute for cholesterol suggests a biophysical mechanism for cholesterol's effect on integrin diffusion. Influences of bilayer thickness, viscosity and organization are discussed as possible explanations for the measured changes in integrin diffusion when the membrane cholesterol concentration is reduced.

Design principles for noninvasive, longitudinal and quantitative cell tracking with nanoparticle-based CT imaging.

PubMed

Meir, Rinat; Betzer, Oshra; Motiei, Menachem; Kronfeld, Noam; Brodie, Chaya; Popovtzer, Rachela

2017-02-01

Contradictory results in clinical trials are preventing the advancement and implementation of cell-based therapy. To explain such results, there is a need to uncover the mystery regarding the fate of the transplanted cells. To answer this need, we developed a technique for noninvasive in vivo cell tracking, which uses gold nanoparticles as contrast agents for CT imaging. Herein, we investigate the design principles of this technique for intramuscular transplantation of therapeutic cells. Longitudinal studies were performed, displaying the ability to track cells over long periods of time. As few as 500 cells could be detected and a way to quantify the number of cells visualized by CT was demonstrated. Moreover, monitoring of cell functionality was demonstrated on a mouse model of Duchenne muscular dystrophy. This cell-tracking technology has the potential to become an essential tool in pre-clinical as well as clinical trials and to advance the future of cell therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

On the holographic 3D tracking of in vitro cells characterized by a highly-morphological change.

PubMed

Memmolo, Pasquale; Iannone, Maria; Ventre, Maurizio; Netti, Paolo Antonio; Finizio, Andrea; Paturzo, Melania; Ferraro, Pietro

2012-12-17

Digital Holography (DH) in microscopic configuration is a powerful tool for the imaging of micro-objects contained into a three dimensional (3D) volume, by a single-shot image acquisition. Many studies report on the ability of DH to track particle, microorganism and cells in 3D. However, very few investigations are performed with objects that change severely their morphology during the observation period. Here we study DH as a tool for 3D tracking an osteosarcoma cell line for which extensive changes in cell morphology are associated to cell motion. Due to the great unpredictable morphological change, retrieving cell's position in 3D can become a complicated issue. We investigate and discuss in this paper how the tridimensional position can be affected by the continuous change of the cells. Moreover we propose and test some strategies to afford the problems and compare it with others approaches. Finally, results on the 3D tracking and comments are reported and illustrated.

An improved KCF tracking algorithm based on multi-feature and multi-scale

NASA Astrophysics Data System (ADS)

Wu, Wei; Wang, Ding; Luo, Xin; Su, Yang; Tian, Weiye

2018-02-01

The purpose of visual tracking is to associate the target object in a continuous video frame. In recent years, the method based on the kernel correlation filter has become the research hotspot. However, the algorithm still has some problems such as video capture equipment fast jitter, tracking scale transformation. In order to improve the ability of scale transformation and feature description, this paper has carried an innovative algorithm based on the multi feature fusion and multi-scale transform. The experimental results show that our method solves the problem that the target model update when is blocked or its scale transforms. The accuracy of the evaluation (OPE) is 77.0%, 75.4% and the success rate is 69.7%, 66.4% on the VOT and OTB datasets. Compared with the optimal one of the existing target-based tracking algorithms, the accuracy of the algorithm is improved by 6.7% and 6.3% respectively. The success rates are improved by 13.7% and 14.2% respectively.

Mechanisms Underlying Selective Neuronal Tracking of Attended Speech at a ‘Cocktail Party’

PubMed Central

Zion Golumbic, Elana M.; Ding, Nai; Bickel, Stephan; Lakatos, Peter; Schevon, Catherine A.; McKhann, Guy M.; Goodman, Robert R.; Emerson, Ronald; Mehta, Ashesh D.; Simon, Jonathan Z.; Poeppel, David; Schroeder, Charles E.

2013-01-01

Summary The ability to focus on and understand one talker in a noisy social environment is a critical social-cognitive capacity, whose underlying neuronal mechanisms are unclear. We investigated the manner in which speech streams are represented in brain activity and the way that selective attention governs the brain’s representation of speech using a ‘Cocktail Party’ Paradigm, coupled with direct recordings from the cortical surface in surgical epilepsy patients. We find that brain activity dynamically tracks speech streams using both low frequency phase and high frequency amplitude fluctuations, and that optimal encoding likely combines the two. In and near low level auditory cortices, attention ‘modulates’ the representation by enhancing cortical tracking of attended speech streams, but ignored speech remains represented. In higher order regions, the representation appears to become more ‘selective,’ in that there is no detectable tracking of ignored speech. This selectivity itself seems to sharpen as a sentence unfolds. PMID:23473326

Gold nanoparticles for non-invasive cell tracking with CT imaging

NASA Astrophysics Data System (ADS)

Meir, Rinat; Betzer, Oshra; Barnoy, Eran; Motiei, Menachem; Popovtzer, Rachela

2018-02-01

Cell-based therapies use living cells with therapeutic traits to treat various diseases. This is a beneficial alternative for diseases that existing medicine cannot cure efficiently. However, inconsistent results in clinical trials are preventing the advancement and implementation of cell-based therapy. In order to explain such results, there is a need to discover the fate of the transplanted cells. To answer this need, we developed a technique for noninvasive in vivo cell tracking, which uses gold nanoparticles as contrast agents for CT imaging. Herein, we investigate the design principles of this technique for intramuscular transplantation of therapeutic cells. Longitudinal studies were performed, demonstrating the ability to track cells over long periods of time. As few as 500 cells could be detected and a way to quantify the number of cells visualized by CT was demonstrated. This cell-tracking technology has the potential to become an essential tool in pre-clinical studies as well as in clinical trials and advance cell therapy.

Adaptive Backstepping-Based Neural Tracking Control for MIMO Nonlinear Switched Systems Subject to Input Delays.

PubMed

Niu, Ben; Li, Lu

2018-06-01

This brief proposes a new neural-network (NN)-based adaptive output tracking control scheme for a class of disturbed multiple-input multiple-output uncertain nonlinear switched systems with input delays. By combining the universal approximation ability of radial basis function NNs and adaptive backstepping recursive design with an improved multiple Lyapunov function (MLF) scheme, a novel adaptive neural output tracking controller design method is presented for the switched system. The feature of the developed design is that different coordinate transformations are adopted to overcome the conservativeness caused by adopting a common coordinate transformation for all subsystems. It is shown that all the variables of the resulting closed-loop system are semiglobally uniformly ultimately bounded under a class of switching signals in the presence of MLF and that the system output can follow the desired reference signal. To demonstrate the practicability of the obtained result, an adaptive neural output tracking controller is designed for a mass-spring-damper system.

Player-Tracking Technology: Half-Full or Half-Empty Glass?

PubMed

Buchheit, Martin; Simpson, Ben Michael

2017-04-01

With the ongoing development of microtechnology, player tracking has become one of the most important components of load monitoring in team sports. The 3 main objectives of player tracking are better understanding of practice (provide an objective, a posteriori evaluation of external load and locomotor demands of any given session or match), optimization of training-load patterns at the team level, and decision making on individual players' training programs to improve performance and prevent injuries (eg, top-up training vs unloading sequences, return to play progression). This paper discusses the basics of a simple tracking approach and the need to integrate multiple systems. The limitations of some of the most used variables in the field (including metabolic-power measures) are debated, and innovative and potentially new powerful variables are presented. The foundations of a successful player-monitoring system are probably laid on the pitch first, in the way practitioners collect their own tracking data, given the limitations of each variable, and how they report and use all this information, rather than in the technology and the variables per se. Overall, the decision to use any tracking technology or new variable should always be considered with a cost/benefit approach (ie, cost, ease of use, portability, manpower/ability to affect the training program).

High-bandwidth and flexible tracking control for precision motion with application to a piezo nanopositioner.

PubMed

Feng, Zhao; Ling, Jie; Ming, Min; Xiao, Xiao-Hui

2017-08-01

For precision motion, high-bandwidth and flexible tracking are the two important issues for significant performance improvement. Iterative learning control (ILC) is an effective feedforward control method only for systems that operate strictly repetitively. Although projection ILC can track varying references, the performance is still limited by the fixed-bandwidth Q-filter, especially for triangular waves tracking commonly used in a piezo nanopositioner. In this paper, a wavelet transform-based linear time-varying (LTV) Q-filter design for projection ILC is proposed to compensate high-frequency errors and improve the ability to tracking varying references simultaneously. The LVT Q-filter is designed based on the modulus maximum of wavelet detail coefficients calculated by wavelet transform to determine the high-frequency locations of each iteration with the advantages of avoiding cross-terms and segmenting manually. The proposed approach was verified on a piezo nanopositioner. Experimental results indicate that the proposed approach can locate the high-frequency regions accurately and achieve the best performance under varying references compared with traditional frequency-domain and projection ILC with a fixed-bandwidth Q-filter, which validates that through implementing the LTV filter on projection ILC, high-bandwidth and flexible tracking can be achieved simultaneously by the proposed approach.

An open source framework for tracking and state estimation ('Stone Soup')

NASA Astrophysics Data System (ADS)

Thomas, Paul A.; Barr, Jordi; Balaji, Bhashyam; White, Kruger

2017-05-01

The ability to detect and unambiguously follow all moving entities in a state-space is important in multiple domains both in defence (e.g. air surveillance, maritime situational awareness, ground moving target indication) and the civil sphere (e.g. astronomy, biology, epidemiology, dispersion modelling). However, tracking and state estimation researchers and practitioners have difficulties recreating state-of-the-art algorithms in order to benchmark their own work. Furthermore, system developers need to assess which algorithms meet operational requirements objectively and exhaustively rather than intuitively or driven by personal favourites. We have therefore commenced the development of a collaborative initiative to create an open source framework for production, demonstration and evaluation of Tracking and State Estimation algorithms. The initiative will develop a (MIT-licensed) software platform for researchers and practitioners to test, verify and benchmark a variety of multi-sensor and multi-object state estimation algorithms. The initiative is supported by four defence laboratories, who will contribute to the development effort for the framework. The tracking and state estimation community will derive significant benefits from this work, including: access to repositories of verified and validated tracking and state estimation algorithms, a framework for the evaluation of multiple algorithms, standardisation of interfaces and access to challenging data sets. Keywords: Tracking,

Evidence-based use of electronic clinical tracking systems in advanced practice registered nurse education: an integrative review.

PubMed

Branstetter, M Laurie; Smith, Lynette S; Brooks, Andrea F

2014-07-01

Over the past decade, the federal government has mandated healthcare providers to incorporate electronic health records into practice by 2015. This technological update in healthcare documentation has generated a need for advanced practice RN programs to incorporate information technology into education. The National Organization of Nurse Practitioner Faculties created core competencies to guide program standards for advanced practice RN education. One core competency is Technology and Information Literacy. Educational programs are moving toward the utilization of electronic clinical tracking systems to capture students' clinical encounter data. The purpose of this integrative review was to evaluate current research on advanced practice RN students' documentation of clinical encounters utilizing electronic clinical tracking systems to meet advanced practice RN curriculum outcome goals in information technology as defined by the National Organization of Nurse Practitioner Faculties. The state of the science depicts student' and faculty attitudes, preferences, opinions, and data collections of students' clinical encounters. Although electronic clinical tracking systems were utilized to track students' clinical encounters, these systems have not been evaluated for meeting information technology core competency standards. Educational programs are utilizing electronic clinical tracking systems with limited evidence-based literature evaluating the ability of these systems to meet the core competencies in advanced practice RN programs.

Advanced data assimilation in strongly nonlinear dynamical systems

NASA Technical Reports Server (NTRS)

Miller, Robert N.; Ghil, Michael; Gauthiez, Francois

1994-01-01

Advanced data assimilation methods are applied to simple but highly nonlinear problems. The dynamical systems studied here are the stochastically forced double well and the Lorenz model. In both systems, linear approximation of the dynamics about the critical points near which regime transitions occur is not always sufficient to track their occurrence or nonoccurrence. Straightforward application of the extended Kalman filter yields mixed results. The ability of the extended Kalman filter to track transitions of the double-well system from one stable critical point to the other depends on the frequency and accuracy of the observations relative to the mean-square amplitude of the stochastic forcing. The ability of the filter to track the chaotic trajectories of the Lorenz model is limited to short times, as is the ability of strong-constraint variational methods. Examples are given to illustrate the difficulties involved, and qualitative explanations for these difficulties are provided. Three generalizations of the extended Kalman filter are described. The first is based on inspection of the innovation sequence, that is, the successive differences between observations and forecasts; it works very well for the double-well problem. The second, an extension to fourth-order moments, yields excellent results for the Lorenz model but will be unwieldy when applied to models with high-dimensional state spaces. A third, more practical method--based on an empirical statistical model derived from a Monte Carlo simulation--is formulated, and shown to work very well. Weak-constraint methods can be made to perform satisfactorily in the context of these simple models, but such methods do not seem to generalize easily to practical models of the atmosphere and ocean. In particular, it is shown that the equations derived in the weak variational formulation are difficult to solve conveniently for large systems.

The ship-borne infrared searching and tracking system based on the inertial platform

NASA Astrophysics Data System (ADS)

Li, Yan; Zhang, Haibo

2011-08-01

As a result of the radar system got interferenced or in the state of half silent ,it can cause the guided precision drop badly In the modern electronic warfare, therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings, but when interference is in the process of radar leading ,especially the electro-optical equipment is influenced by the roll, pitch and yaw rotation ,it can affect the target appear outside of the field of optoelectronic devices for a long time, so the infrared optoelectronic equipment can not exert the superiority, and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly , the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene, the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking, when the lead deviation of the radar is great.

High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera Tracking

NASA Astrophysics Data System (ADS)

Liss, J.; Dunagan, S. E.; Johnson, R. R.; Chang, C. S.; LeBlanc, S. E.; Shinozuka, Y.; Redemann, J.; Flynn, C. J.; Segal-Rosenhaimer, M.; Pistone, K.; Kacenelenbogen, M. S.; Fahey, L.

2016-12-01

High Precision Sunphotometer using Wide Dynamic Range (WDR) Camera TrackingThe NASA Ames Sun-photometer-Satellite Group, DOE, PNNL Atmospheric Sciences and Global Change Division, and NASA Goddard's AERONET (AErosol RObotic NETwork) team recently collaborated on the development of a new airborne sunphotometry instrument that provides information on gases and aerosols extending far beyond what can be derived from discrete-channel direct-beam measurements, while preserving or enhancing many of the desirable AATS features (e.g., compactness, versatility, automation, reliability). The enhanced instrument combines the sun-tracking ability of the current 14-Channel NASA Ames AATS-14 with the sky-scanning ability of the ground-based AERONET Sun/sky photometers, while extending both AATS-14 and AERONET capabilities by providing full spectral information from the UV (350 nm) to the SWIR (1,700 nm). Strengths of this measurement approach include many more wavelengths (isolated from gas absorption features) that may be used to characterize aerosols and detailed (oversampled) measurements of the absorption features of specific gas constituents. The Sky Scanning Sun Tracking Airborne Radiometer (3STAR) replicates the radiometer functionality of the AATS-14 instrument but incorporates modern COTS technologies for all instruments subsystems. A 19-channel radiometer bundle design is borrowed from a commercial water column radiance instrument manufactured by Biospherical Instruments of San Diego California (ref, Morrow and Hooker)) and developed using NASA funds under the Small Business Innovative Research (SBIR) program. The 3STAR design also incorporates the latest in robotic motor technology embodied in Rotary actuators from Oriental motor Corp. having better than 15 arc seconds of positioning accuracy. Control system was designed, tested and simulated using a Hybrid-Dynamical modeling methodology. The design also replaces the classic quadrant detector tracking sensor with a wide dynamic range camera that provides a high precision solar position tracking signal as well as an image of the sky in the 45° field of view around the solar axis, which can be of great assistance in flagging data for cloud effects or other factors that might impact data quality.

Automated cell tracking and analysis in phase-contrast videos (iTrack4U): development of Java software based on combined mean-shift processes.

PubMed

Cordelières, Fabrice P; Petit, Valérie; Kumasaka, Mayuko; Debeir, Olivier; Letort, Véronique; Gallagher, Stuart J; Larue, Lionel

2013-01-01

Cell migration is a key biological process with a role in both physiological and pathological conditions. Locomotion of cells during embryonic development is essential for their correct positioning in the organism; immune cells have to migrate and circulate in response to injury. Failure of cells to migrate or an inappropriate acquisition of migratory capacities can result in severe defects such as altered pigmentation, skull and limb abnormalities during development, and defective wound repair, immunosuppression or tumor dissemination. The ability to accurately analyze and quantify cell migration is important for our understanding of development, homeostasis and disease. In vitro cell tracking experiments, using primary or established cell cultures, are often used to study migration as cells can quickly and easily be genetically or chemically manipulated. Images of the cells are acquired at regular time intervals over several hours using microscopes equipped with CCD camera. The locations (x,y,t) of each cell on the recorded sequence of frames then need to be tracked. Manual computer-assisted tracking is the traditional method for analyzing the migratory behavior of cells. However, this processing is extremely tedious and time-consuming. Most existing tracking algorithms require experience in programming languages that are unfamiliar to most biologists. We therefore developed an automated cell tracking program, written in Java, which uses a mean-shift algorithm and ImageJ as a library. iTrack4U is a user-friendly software. Compared to manual tracking, it saves considerable amount of time to generate and analyze the variables characterizing cell migration, since they are automatically computed with iTrack4U. Another major interest of iTrack4U is the standardization and the lack of inter-experimenter differences. Finally, iTrack4U is adapted for phase contrast and fluorescent cells.

Flight-test evaluation of two electronic display formats for approach to landing under instrument conditions

NASA Technical Reports Server (NTRS)

Morello, S. A.; Knox, C. E.; Steinmetz, G. G.

1977-01-01

The results of a flight evaluation of two electronic display formats for the approach to landing under instrument conditions are presented. The evaluation was conducted for a base-line electronic display format and for the same format with runway symbology and track information added. The evaluation was conducted during 3 deg, manual straight-in approaches with and without initial localizer offsets. Flight path tracking performance data and pilot subjective comments were examined with regard to the pilot's ability to capture and maintain localizer and glide slope by using both display formats.

Lineage mapper: A versatile cell and particle tracker

NASA Astrophysics Data System (ADS)

Chalfoun, Joe; Majurski, Michael; Dima, Alden; Halter, Michael; Bhadriraju, Kiran; Brady, Mary

2016-11-01

The ability to accurately track cells and particles from images is critical to many biomedical problems. To address this, we developed Lineage Mapper, an open-source tracker for time-lapse images of biological cells, colonies, and particles. Lineage Mapper tracks objects independently of the segmentation method, detects mitosis in confluence, separates cell clumps mistakenly segmented as a single cell, provides accuracy and scalability even on terabyte-sized datasets, and creates division and/or fusion lineages. Lineage Mapper has been tested and validated on multiple biological and simulated problems. The software is available in ImageJ and Matlab at isg.nist.gov.

Cant deficiency, curving speeds and tilt

DOT National Transportation Integrated Search

2011-01-01

In the US, increasing passenger speeds to improve trip time usually involves increasing speeds through curves. Increasing speeds through curves will increase the lateral force exerted on track during curving, thus requiring more intensive track maint...

Tracking the Construction of Episodic Future Thoughts

ERIC Educational Resources Information Center

D'Argembeau, Arnaud; Mathy, Arnaud

2011-01-01

The ability to mentally simulate possible futures ("episodic future thinking") is of fundamental importance for various aspects of human cognition and behavior, but precisely how humans construct mental representations of future events is still essentially unknown. We suggest that episodic future thoughts consist of transitory patterns…

The Reciprocal Relations between Morphological Processes and Reading

ERIC Educational Resources Information Center

Kruk, Richard S.; Bergman, Krista

2013-01-01

Reciprocal relations between emerging morphological processes and reading skills were examined in a longitudinal study tracking children from Grade 1 through Grade 3. The aim was to examine predictive relationships between productive morphological processing involving composing and decomposing of inflections and derivations, reading ability for…

A Special Report on Middle Schools.

ERIC Educational Resources Information Center

Hollifield, John H.

1988-01-01

The first Center for Research on Elementary and Middle Schools (CREM) report describes the structures and practices currently used at all school levels for staffing, grouping, and scheduling. The report assesses the effects of departmentalization, tracking, ability grouping, and grade spans on student learning and development. (MLH)

REAL-TIME MONITORING FOR TOXICITY CAUSED BY HARMFUL ALGAL BLOOMS AND OTHER WATER QUALITY PERTURBATIONS

EPA Science Inventory

This project, sponsored by EPA's Environmental Monitoring for Public Access and Community Tracking (EMPACT) program, evaluated the ability of an automated biological monitoring system that measures fish ventilatory responses (ventilatory rate, ventilatory depth, and cough rate) t...

Chaos synchronization and Nelder-Mead search for parameter estimation in nonlinear pharmacological systems: Estimating tumor antigenicity in a model of immunotherapy.

PubMed

Pillai, Nikhil; Craig, Morgan; Dokoumetzidis, Aristeidis; Schwartz, Sorell L; Bies, Robert; Freedman, Immanuel

2018-06-19

In mathematical pharmacology, models are constructed to confer a robust method for optimizing treatment. The predictive capability of pharmacological models depends heavily on the ability to track the system and to accurately determine parameters with reference to the sensitivity in projected outcomes. To closely track chaotic systems, one may choose to apply chaos synchronization. An advantageous byproduct of this methodology is the ability to quantify model parameters. In this paper, we illustrate the use of chaos synchronization combined with Nelder-Mead search to estimate parameters of the well-known Kirschner-Panetta model of IL-2 immunotherapy from noisy data. Chaos synchronization with Nelder-Mead search is shown to provide more accurate and reliable estimates than Nelder-Mead search based on an extended least squares (ELS) objective function. Our results underline the strength of this approach to parameter estimation and provide a broader framework of parameter identification for nonlinear models in pharmacology. Copyright © 2018 Elsevier Ltd. All rights reserved.

Single-Molecule Tracking Photoactivated Localization Microscopy to Map Nano-Scale Structure and Dynamics in Living Spines

PubMed Central

MacGillavry, Harold D.; Blanpied, Thomas A.

2013-01-01

Super-resolution microscopy has rapidly become an indispensable tool in cell biology and neuroscience by enabling measurement in live cells of structures smaller than the classical limit imposed by diffraction. The most widely applied super-resolution method currently is localization microscopy, which takes advantage of the ability to determine the position of individual fluorescent molecules with nanometer accuracy even in cells. By iteratively measuring sparse subsets of photoactivatable fluorescent proteins, protein distribution in macromolecular structures can be accurately reconstructed. Moreover, the motion trajectories of individual molecules within cells can be measured, providing unique ability to measure transport kinetics, exchange rates, and binding affinities of even small subsets of molecules with high temporal resolution and great spatial specificity. This unit describes protocols to measure and quantify the distribution of scaffold proteins within single synapses of cultured hippocampal neurons, and to track and measure the diffusion of intracellular constituents of the neuronal plasma membrane. PMID:25429311

Introduction and Progress of APOSOS Project

NASA Astrophysics Data System (ADS)

Zhao, You; Gao, P. Q.; Shen, Ming; Chaudhry, Maqbool A.; Guo, Xiaozhong; Teng, D. P.; Yang, Datao; Yu, Huanhuan; Zhao, Zhe

Asia-Pacific Ground-Based Optical Satellite Observation System (APOSOS) project is based on members of Asia-Pacific Space Cooperation Organization (APSCO). Its aim is to develop a regional or even global satellite tracking network basically composed of optical trackers. The system will be used to track objects of interest or space-debris for the safety of spacecraft launch mission or the intactness of operational satellites. The system will benefit from the distribution of APSCO members and multi-national fund support or technical cooperation. Thus APOSOS will have a potential capability to observe all the satellites orbiting earth with high precision but relatively low cost. This paper will present the introduction, progress and current status of APOSOS project, including: System Requirements Definition, System Main Mission, System Goal, System design, Services and Clients, Organization Framework of Observation Center, Major Function of Observation Center, Establishment of Observation Plan, Format Standard for Exchanging Data, Data Policy, Implementation Schedule, etc.. APOSOS will build a unified surveillance network from observational facilities of member states involved, to utilize the wide geographical distribution advantage of multi-country. It will be operated under the coordination of APSCO observation mission management department. (1)APOSOS should conduct observation missions of specific satellites, space-debris or other space objects of interest, based on requirements of member states. APOSOS should fulfill the basic requirement for satellites observation and tracking missions. And it should also have the potential ability of small debris detection to support collision avoidance planning, which can protect the members high valued space assets. (2)In some particular application, APOSOS would be able to be used for long-term tracking of specific space object of interest, and have the ability of data processing and analysis, so as to provide conjunction assessment, collision probability calculation and avoidance planning for space assets. (3)APOSOS should have the capability of publishing information and sharing data among member states, with the ability to deal with user’s requests for data and mange the data in different levels. (4)APOSOS should have the capability of providing services such as technical consultation, training and science popularization.

Acceleration endurance with pressure breathing during G with and without a counterpressure vest.

PubMed

Walker, Thomas B; Dart, Todd; Morgan, Thomas R; Balldin, Ulf I

2014-04-01

The purpose of this study was to test whether pressure breathing during G (PBC) without a counterpressure vest negatively influences G endurance or increases breathing fatigue during extended duration high-G exposures. While using PBG, 10 subjects underwent 2 trials of +3 Gz exposures: once when wearing a counterpressure vest and once without. The exposures consisted of a relaxed, gradual G onset run until peripheral or central light loss, a straining rapid onset GC run to +6 Gz for 15 s, and a simulated aerial combat maneuver (SACM) G profile consisting of 10-s periods varying between +5 Gz and +9 Gz, during which subjects executed a hand-eye tracking task. The SACM endpoint was light loss or exhaustion. Subjects provided ratings of subjective effort and discomfort after the SACM. Significant differences were found between the vest and no-vest conditions for only 3 of 19 measures: heart rate under G and two measures of tracking ability. The vast majority of data indicated no difference between the vest and no-vest conditions for performance under G. This experiment supports previous studies and expands those previous results by increasing the duration of PBG exposure shown to not be influenced by wearing of the vest. We conclude that there is likely no practical advantage to wearing a counterpressure vest during PBG.

Tri-track: free software for large-scale particle tracking.

PubMed

Vallotton, Pascal; Olivier, Sandra

2013-04-01

The ability to correctly track objects in time-lapse sequences is important in many applications of microscopy. Individual object motions typically display a level of dynamic regularity reflecting the existence of an underlying physics or biology. Best results are obtained when this local information is exploited. Additionally, if the particle number is known to be approximately constant, a large number of tracking scenarios may be rejected on the basis that they are not compatible with a known maximum particle velocity. This represents information of a global nature, which should ideally be exploited too. Some time ago, we devised an efficient algorithm that exploited both types of information. The tracking task was reduced to a max-flow min-cost problem instance through a novel graph structure that comprised vertices representing objects from three consecutive image frames. The algorithm is explained here for the first time. A user-friendly implementation is provided, and the specific relaxation mechanism responsible for the method's effectiveness is uncovered. The software is particularly competitive for complex dynamics such as dense antiparallel flows, or in situations where object displacements are considerable. As an application, we characterize a remarkable vortex structure formed by bacteria engaged in interstitial motility.

Relationships between changes in Sustained Fronto-Striatal Connectivity and Positive Affect with Antidepressant Treatment in Major Depression

PubMed Central

Heller, Aaron S.; Johnstone, Tom; Light, Sharee; Peterson, Michael J.; Kolden, Gregory G.; Kalin, Ned H.; Davidson, Richard J.

2012-01-01

Objective Deficits in positive affect and their neural bases have been associated with major depression. However, whether reductions in positive affect result solely from an overall reduction in nucleus accumbens activity and fronto-striatal connectivity or the additional inability to sustain engagement over time of this network is unknown. Accordingly, we sought to determine whether treatment-induced changes in the ability to sustain nucleus accumbens activity and fronto-striatal connectivity during the regulation of positive affect are associated with gains in positive affect. Method Using fMRI, we assessed the ability to sustain activity in reward-related networks when attempting to increase positive emotion during performance of an emotion regulation paradigm in 21 depressed patients prior to, and after 2 months of antidepressant treatment. 14 healthy control subjects were scanned over the same interval. Results After 2 months of treatment, self-reported positive affect increased. Those patients demonstrating the largest increases in sustained nucleus accumbens activity over the 2 months were those demonstrating the largest increases in positive affect. In addition, those patients demonstrating the largest increases in sustained fronto-striatal connectivity were also those demonstrating the largest increases in positive affect when controlling for negative affect. Healthy controls showed none of these associations. Conclusions Treatment induced changes in the sustained engagement of fronto-striatal circuitry tracks the experience of positive emotion in daily life. Studies examining reduced positive affect in a variety of psychiatric disorders might benefit from examining the temporal dynamics of brain activity when attempting to understand changes in daily positive affect. PMID:23223803

Mitochondrial Dynamics Tracking with Two-Photon Phosphorescent Terpyridyl Iridium(III) Complexes

NASA Astrophysics Data System (ADS)

Huang, Huaiyi; Zhang, Pingyu; Qiu, Kangqiang; Huang, Juanjuan; Chen, Yu; Ji, Liangnian; Chao, Hui

2016-02-01

Mitochondrial dynamics, including fission and fusion, control the morphology and function of mitochondria, and disruption of mitochondrial dynamics leads to Parkinson’s disease, Alzheimer’s disease, metabolic diseases, and cancers. Currently, many types of commercial mitochondria probes are available, but high excitation energy and low photo-stability render them unsuitable for tracking mitochondrial dynamics in living cells. Therefore, mitochondrial targeting agents that exhibit superior anti-photo-bleaching ability, deep tissue penetration and intrinsically high three-dimensional resolutions are urgently needed. Two-photon-excited compounds that use low-energy near-infrared excitation lasers have emerged as non-invasive tools for cell imaging. In this work, terpyridyl cyclometalated Ir(III) complexes (Ir1-Ir3) are demonstrated as one- and two-photon phosphorescent probes for real-time imaging and tracking of mitochondrial morphology changes in living cells.

MRI-based dynamic tracking of an untethered ferromagnetic microcapsule navigating in liquid

NASA Astrophysics Data System (ADS)

Dahmen, Christian; Belharet, Karim; Folio, David; Ferreira, Antoine; Fatikow, Sergej

2016-04-01

The propulsion of ferromagnetic objects by means of MRI gradients is a promising approach to enable new forms of therapy. In this work, necessary techniques are presented to make this approach work. This includes path planning algorithms working on MRI data, ferromagnetic artifact imaging and a tracking algorithm which delivers position feedback for the ferromagnetic objects, and a propulsion sequence to enable interleaved magnetic propulsion and imaging. Using a dedicated software environment, integrating path-planning methods and real-time tracking, a clinical MRI system is adapted to provide this new functionality for controlled interventional targeted therapeutic applications. Through MRI-based sensing analysis, this article aims to propose a framework to plan a robust pathway to enhance the navigation ability to reach deep locations in the human body. The proposed approaches are validated with different experiments.

Plume-tracking robots: a new application of chemical sensors.

PubMed

Ishid, H; Nakamoto, T; Moriizumi, T; Kikas, T; Janata, J

2001-04-01

Many animals have the ability to search for odor sources by tracking their plumes. Some of the key features of this search behavior have been successfully transferred to robot platforms, although the capabilities of animals are still beyond the current level of sensor technologies. The examples described in this paper are (1) incorporating into a wheeled robot the upwind surges and casting used by moths in tracking pheromone plumes, (2) extracting useful information from the response patterns of a chemical sensor array patterned after the spatially distributed chemoreceptors of some animals, and (3) mimicking the fanning behavior of silkworm moths to enhance the reception of chemical signals by drawing molecules from one direction. The achievements so far and current efforts are reviewed to illustrate the steps to be taken toward future development of this technology.

Quality Improvement Strategies in Accountable Care Organization Hospitals.

PubMed

Mora, Arthur M; Walker, Daniel

2016-01-01

Accountable Care Organizations (ACOs) are hoped to lower costs and improve health care quality. However, hospitals remain unsure how to bring about the quality improvement (QI) required to increase financial viability. This success may hinge on the use of sophisticated measurement tracking and the use of multiple QI tools. This study aims to assess the current approaches that ACO hospitals are using to improve quality and to compare their strategies with non-ACO hospitals. The 2013 American Hospital Association's Annual Survey and the Survey of Care Systems and Payment data were merged to identify ACO and non-ACO hospitals. ACO and non-ACO hospital rates of reported use of multiple QI tools and the ability to detect and track readmissions across organizational boundaries were compared. ACO hospitals were significantly less likely to use only 1 QI tool (43.5% vs 65.2%; P < .001) and more likely to use 2 (36.4% vs 28.1%; P < .05), 3 (12.1% vs 6.5%; P < .001), or 4 (8.0% vs 0.2%; P < .001) QI tools. ACO hospitals were significantly more likely to have the capability to detect readmissions (34.1% vs 22.8%; P < .001) and track readmissions (90.5% vs 85.7%; P < .05). Results suggest that ACO hospitals are incorporating more sophisticated measurements and combinations of QI tools than non-ACO hospitals. It remains to be seen whether this leads to accelerated changes across the quality domains in ACO hospitals.

Consistent detection and identification of individuals in a large camera network

NASA Astrophysics Data System (ADS)

Colombo, Alberto; Leung, Valerie; Orwell, James; Velastin, Sergio A.

2007-10-01

In the wake of an increasing number of terrorist attacks, counter-terrorism measures are now a main focus of many research programmes. An important issue for the police is the ability to track individuals and groups reliably through underground stations, and in the case of post-event analysis, to be able to ascertain whether specific individuals have been at the station previously. While there exist many motion detection and tracking algorithms, the reliable deployment of them in a large network is still ongoing research. Specifically, to track individuals through multiple views, on multiple levels and between levels, consistent detection and labelling of individuals is crucial. In view of these issues, we have developed a change detection algorithm to work reliably in the presence of periodic movements, e.g. escalators and scrolling advertisements, as well as a content-based retrieval technique for identification. The change detection technique automatically extracts periodically varying elements in the scene using Fourier analysis, and constructs a Markov model for the process. Training is performed online, and no manual intervention is required, making this system suitable for deployment in large networks. Experiments on real data shows significant improvement over existing techniques. The content-based retrieval technique uses MPEG-7 descriptors to identify individuals. Given the environment under which the system operates, i.e. at relatively low resolution, this approach is suitable for short timescales. For longer timescales, other forms of identification such as gait, or if the resolution allows, face recognition, will be required.

Towards a theory of individual differences in statistical learning

PubMed Central

Bogaerts, Louisa; Christiansen, Morten H.; Frost, Ram

2017-01-01

In recent years, statistical learning (SL) research has seen a growing interest in tracking individual performance in SL tasks, mainly as a predictor of linguistic abilities. We review studies from this line of research and outline three presuppositions underlying the experimental approach they employ: (i) that SL is a unified theoretical construct; (ii) that current SL tasks are interchangeable, and equally valid for assessing SL ability; and (iii) that performance in the standard forced-choice test in the task is a good proxy of SL ability. We argue that these three critical presuppositions are subject to a number of theoretical and empirical issues. First, SL shows patterns of modality- and informational-specificity, suggesting that SL cannot be treated as a unified construct. Second, different SL tasks may tap into separate sub-components of SL that are not necessarily interchangeable. Third, the commonly used forced-choice tests in most SL tasks are subject to inherent limitations and confounds. As a first step, we offer a methodological approach that explicitly spells out a potential set of different SL dimensions, allowing for better transparency in choosing a specific SL task as a predictor of a given linguistic outcome. We then offer possible methodological solutions for better tracking and measuring SL ability. Taken together, these discussions provide a novel theoretical and methodological approach for assessing individual differences in SL, with clear testable predictions. This article is part of the themed issue ‘New frontiers for statistical learning in the cognitive sciences’. PMID:27872377

Solar furnaces or swamp coolers: costs and benefits of water use by solar-tracking flowers of the alpine snow buttercup, Ranunculus adoneus.

PubMed

Galen, Candace

2006-06-01

Solar tracking or heliotropism simultaneously raises organ temperature and light interception. For leaves and flowers carbon gain is maximized at the expense of water loss. In this study I explore how costs and benefits associated with water use by solar-tracking flowers of the alpine snow buttercup, Ranunculus adoneus change with ambient temperature. First, I test whether heliotropism increases the water cost of reproduction in the snow buttercup under extant alpine conditions. I then explore whether water use for evaporative cooling in solar-tracking flowers reduces the risk of over-heating as temperatures increase. Solar tracking, by elevating floral temperature and irradiance causes a 29% increase in water uptake by flowers. Gas exchange measurements suggest that the extra water taken up by solar-tracking flowers is released through transpiration. Transpirational cooling in turn allows solar-tracking flowers to gain advantages of enhanced light interception and warmth while reducing the risk of over-heating. Transpiration reduces excess temperature in solar-tracking flowers, but at a water cost. Results show that even in cool alpine habitats, flower heliotropism has water costs to balance its reproductive advantages. Plants with solar-tracking flowers may tolerate hotter conditions if soil moisture is plentiful, but not under drought.

Taking time to feel our body: Steady increases in heartbeat perception accuracy and decreases in alexithymia over 9 months of contemplative mental training.

PubMed

Bornemann, Boris; Singer, Tania

2017-03-01

The ability to accurately perceive signals from the body has been shown to be important for physical and psychological health as well as understanding one's emotions. Despite the importance of this skill, often indexed by heartbeat perception accuracy (HBPa), little is known about its malleability. Here, we investigated whether contemplative mental practice can increase HBPa. In the context of a 9-month mental training study, the ReSource Project, two matched cohorts (n = 77 and n = 79) underwent three training modules of 3 months' duration that targeted attentional and interoceptive abilities (Presence module), socio-affective (Affect module), and socio-cognitive (Perspective module) abilities. A third cohort (n = 78) underwent 3 months of practice (Affect module) and a retest control group (n = 84) did not undergo any training. HBPa was measured with a heartbeat tracking task before and after each training module. Emotional awareness was measured by the Toronto Alexithymia Scale (TAS). Participants with TAS scores > 60 at screening were excluded. HBPa was found to increase steadily over the training, with significant and small- to medium-sized effects emerging after 6 months (Cohen's d = .173) and 9 months (d = .273) of mental training. Changes in HBPa were concomitant with and predictive of changes in emotional awareness. Our results suggest that HBPa can indeed be trained through intensive contemplative practice. The effect takes longer than the 8 weeks of typical mindfulness courses to reach meaningful magnitude. These increments in interoceptive accuracy and the related improvements in emotional awareness point to opportunities for improving physical and psychological health through contemplative mental training. © 2016 Society for Psychophysiological Research.

Vermicomposting of winery wastes: a laboratory study.

PubMed

Nogales, Rogelio; Cifuentes, Celia; Benítez, Emilio

2005-01-01

In Mediterranean countries, millions of tons of wastes from viticulture and winery industries are produced every year. This study describes the ability of the earthworm Eisenia andrei to compost different winery wastes (spent grape marc, vinasse biosolids, lees cakes, and vine shoots) into valuable agricultural products. The evolution of earthworm biomass and enzyme activities was tracked for 16 weeks of vermicomposting, on a laboratory scale. Increases in earthworm biomass for all winery wastes proved lower than in manure. Changes in hydrolytic enzymes and overall microbial activities during the vermicomposting process indicated the biodegradation of the winery wastes. Vermicomposting improved the agronomic value of the winery wastes by reducing the C:N ratio, conductivity and phytotoxicity, while increasing the humic materials, nutrient contents, and pH in all cases. Thus, winery wastes show potential as raw substrates in vermicomposting, although further research is needed to evaluate the feasibility of such wastes in large-scale vermicomposting systems.

Gambling involvement and increased risk of gambling problems.

PubMed

Phillips, James G; Ogeil, Rowan; Chow, Yang-Wai; Blaszczynski, Alex

2013-12-01

The opportunity to gamble has undergone rapid expansion with technology allowing for access to gambling products 24 h a day. This increased online availability challenges governments' abilities to restrict access to gambling. Indeed, the ready access to multiple forms of gambling may potentially contribute to impaired control over urges for problem gamblers. The present study considered whether problem gamblers manifested a tendency to engage in multiple forms of gambling and identified forms of gambling which were more strongly related to problem gambling. In reanalyses of two surveys (Sample 1, N = 464, Sample 2, N = 1141), significant relationships accounting for between 11.3 and 13.5% of the variance were found between the numbers of forms of gambling accessed and degree of problem. Participation in online poker, playing cards and sports wagering were linked to problem gambling. Access to multiple forms of gambling may pose difficulties for the tracking and control of gambling.

Passive acoustic tracking of singing humpback whales (Megaptera novaeangliae) on a northwest Atlantic feeding ground.

PubMed

Stanistreet, Joy E; Risch, Denise; Van Parijs, Sofie M

2013-01-01

Passive acoustic tracking provides an unobtrusive method of studying the movement of sound-producing animals in the marine environment where traditional tracking methods may be costly or infeasible. We used passive acoustic tracking to characterize the fine-scale movements of singing humpback whales (Megaptera novaeangliae) on a northwest Atlantic feeding ground. Male humpback whales produce complex songs, a phenomenon that is well documented in tropical regions during the winter breeding season, but also occurs at higher latitudes during other times of year. Acoustic recordings were made throughout 2009 using an array of autonomous recording units deployed in the Stellwagen Bank National Marine Sanctuary. Song was recorded during spring and fall, and individual singing whales were localized and tracked throughout the array using a correlation sum estimation method on the time-synchronized recordings. Tracks were constructed for forty-three song sessions, revealing a high level of variation in movement patterns in both the spring and fall seasons, ranging from slow meandering to faster directional movement. Tracks were 30 min to 8 h in duration, and singers traveled distances ranging from 0.9 to 20.1 km. Mean swimming speed was 2.06 km/h (SD 0.95). Patterns and rates of movement indicated that most singers were actively swimming. In one case, two singers were tracked simultaneously, revealing a potential acoustic interaction. Our results provide a first description of the movements of singers on a northwest Atlantic feeding ground, and demonstrate the utility of passive acoustic tracking for studying the fine-scale movements of cetaceans within the behavioral context of their calls. These methods have further applications for conservation and management purposes, particularly by enhancing our ability to estimate cetacean densities using passive acoustic monitoring.

Passive Acoustic Tracking of Singing Humpback Whales (Megaptera novaeangliae) on a Northwest Atlantic Feeding Ground

PubMed Central

Stanistreet, Joy E.; Risch, Denise; Van Parijs, Sofie M.

2013-01-01

Passive acoustic tracking provides an unobtrusive method of studying the movement of sound-producing animals in the marine environment where traditional tracking methods may be costly or infeasible. We used passive acoustic tracking to characterize the fine-scale movements of singing humpback whales (Megaptera novaeangliae) on a northwest Atlantic feeding ground. Male humpback whales produce complex songs, a phenomenon that is well documented in tropical regions during the winter breeding season, but also occurs at higher latitudes during other times of year. Acoustic recordings were made throughout 2009 using an array of autonomous recording units deployed in the Stellwagen Bank National Marine Sanctuary. Song was recorded during spring and fall, and individual singing whales were localized and tracked throughout the array using a correlation sum estimation method on the time-synchronized recordings. Tracks were constructed for forty-three song sessions, revealing a high level of variation in movement patterns in both the spring and fall seasons, ranging from slow meandering to faster directional movement. Tracks were 30 min to 8 h in duration, and singers traveled distances ranging from 0.9 to 20.1 km. Mean swimming speed was 2.06 km/h (SD 0.95). Patterns and rates of movement indicated that most singers were actively swimming. In one case, two singers were tracked simultaneously, revealing a potential acoustic interaction. Our results provide a first description of the movements of singers on a northwest Atlantic feeding ground, and demonstrate the utility of passive acoustic tracking for studying the fine-scale movements of cetaceans within the behavioral context of their calls. These methods have further applications for conservation and management purposes, particularly by enhancing our ability to estimate cetacean densities using passive acoustic monitoring. PMID:23593447

Evidence against a speed limit in multiple-object tracking.

PubMed

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.

Current radar-responsive tag development activities at Sandia National Laboratories

NASA Astrophysics Data System (ADS)

Ormesher, Richard C.; Plummer, Kenneth W.; Wells, Lars M.

2004-08-01

Over the past ten years, Sandia has developed RF radar responsive tag systems and supporting technologies for various government agencies and industry partners. RF tags can function as RF transmitters or radar transponders that enable tagging, tracking, and location determination functions. Expertise in tag architecture, microwave and radar design, signal analysis and processing techniques, digital design, modeling and simulation, and testing have been directly applicable to these tag programs. In general, the radar responsive tag designs have emphasized low power, small package size, and the ability to be detected by the radar at long ranges. Recently, there has been an interest in using radar responsive tags for Blue Force tracking and Combat ID (CID). The main reason for this interest is to allow airborne surveillance radars to easily distinguish U.S. assets from those of opposing forces. A Blue Force tracking capability would add materially to situational awareness. Combat ID is also an issue, as evidenced by the fact that approximately one-quarter of all U.S. casualties in the Gulf War took the form of ground troops killed by friendly fire. Because the evolution of warfare in the intervening decade has made asymmetric warfare the norm rather than the exception, swarming engagements in which U.S. forces will be freely intermixed with opposing forces is a situation that must be anticipated. Increasing utilization of precision munitions can be expected to drive fires progressively closer to engaged allied troops at times when visual de-confliction is not an option. In view of these trends, it becomes increasingly important that U.S. ground forces have a widely proliferated all-weather radar responsive tag that communicates to all-weather surveillance. The purpose of this paper is to provide an overview of the recent, current, and future radar responsive research and development activities at Sandia National Laboratories that support both the Blue Force Tracking and Combat ID application. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company for the United States Departments of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Research into the usage of integrated jamming of IR weakening and smoke-screen resisting the IR imaging guided missiles

NASA Astrophysics Data System (ADS)

Wang, Long-tao; Jiang, Ning; Lv, Ming-shan

2015-10-01

With the emergence of the anti-ship missle with the capability of infrared imaging guidance, the traditional single jamming measures, because of the jamming mechanism and technical flaws or unsuitable use, greatly reduced the survival probability of the war-ship in the future naval battle. Intergrated jamming of IR weakening + smoke-screen Can not only make jamming to the search and tracking of IR imaging guidance system , but also has feasibility in conjunction, besides , which also make the best jamming effect. The research conclusion has important realistic meaning for raising the antimissile ability of surface ships. With the development of guidance technology, infrared guidance system has expanded by ir point-source homing guidance to infrared imaging guidance, Infrared imaging guidance has made breakthrough progress, Infrared imaging guidance system can use two-dimensional infrared image information of the target, achieve the precise tracking. Which has Higher guidance precision, better concealment, stronger anti-interference ability and could Target the key parts. The traditional single infrared smoke screen jamming or infrared decoy flare interference cannot be imposed effective interference. So, Research how to effectively fight against infrared imaging guided weapons threat measures and means, improving the surface ship antimissile ability is an urgent need to solve.

Mating behaviour of Pseudodiaptomus annandalei (Copepoda, Calanoida) in calm and turbulent waters

NASA Astrophysics Data System (ADS)

Lee, C. H.; Dahms, H. U.; Cheng, S. H.; Souissi, S.; Schmitt, F. G.; Kumar, R.; Hwang, J. S.

2009-04-01

Behavioral observations of male copepods reveal that they commonly follow female copepods' footprints to find their mates. Female generated environmental signals are primarily of hydromechanical or chemical quality. The intensity of hydromechanical or chemical signals is affected by the hydrodynamic conditions which in turn may modulate a copepod's ability to sense signals in their search for mates in the aquatic environment. We studied the patterns and efficiency of the copepod Pseudodiaptomus annandalei to mate at still and turbulent water conditions during day and night and in different shape and volume experimental containers. The ability of courtship in P. annandalei was recorded to be a negative function of hydromechanical disturbances as the successful mating was observed in still water only. Under turbulent condition males were not able to track a female properly. We records in the present study that both, sequential and simultaneous taxi mechanisms are used by the male P. annandalei to follow either hydromechanic or chemical signals. Our results further reveal that males follow a signal more accurately characterized as a trail. The ability of P. annandalei males to track a three-dimensional trail appears unique, and possibly depends on the persistence of fluid-borne hydromechanical or chemical signals created in low Reynolds number hydrodynamic regimes. Keywords: Mating behavior, Turbulence, Flow, Hydrodynamic conditions

Photoacoustic imaging of angiogenesis in subdermal islet transplant sites

NASA Astrophysics Data System (ADS)

Shi, Wei; Pawlick, Rena; Bruni, Antonio; Rafiei, Yasmin; Pepper, Andrew R.; Gala-Lopez, Boris; Choi, Min; Malcolm, Andrew; Zemp, Roger J.; Shapiro, A. M. James

2016-03-01

Exogenous insulin administration is the mainstay treatment therapy for patients with Type-1 diabetes mellitus (T1DM). However, for select patients, clinical islet transplantation is an alternative therapeutic treatment. In this procedure, islets are transplanted into the hepatic portal vein, and despite improved success within the last decade, obstacles are still associated with this approach. It has been discovered that the subcutaneous space may be an effective alternative site for islet transplantation, and may provide advantages of easy access and potential for simple monitoring. The ability to monitor islet viability and the transplant microenvironment may be key to future success in islet transplantation. A subcutaneous device-less technique has been developed to facilitate angiogenesis in the islet transplant site, however, a method for monitoring the potential engraftment site have yet to be explored fully. Here we demonstrate the ability to track angiogenesis in mice with 1, 2, 3 and 4 weeks post-catheter implant on both sides of the abdomen using a FujiFilm VisualSonics Vevo-LAZR system. Quantitative analysis on vessel densities exhibited gradual vessel growth successfully induced by catheter implantation. Our study demonstrates the ability of employing photoacoustic and micro-ultrasound imaging to track angiogenesis around the catheter site prior to islet transplantation.

Becoming Independent Storytellers: Modeling Children's Development of Narrative Macrostructure

ERIC Educational Resources Information Center

Kelly, Kimberly Reynolds; Bailey, Alison Louise

2013-01-01

For parents to provide effective support for their children's language development, they must be attuned to their child's changing abilities. This study presents a theoretically driven strategy that addresses a methodological challenge present when tracking longitudinally the cessation or "fading" of behaviors by capturing withdrawal of…

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…

(Li)Ability Grouping: The New Susceptibility of School Tracking Systems to Legal Challenges.

ERIC Educational Resources Information Center

Welner, Kevin G.; Oakes, Jeannie

1996-01-01

A survey of case law, desegregation literature, and four cases in which researchers served as expert witnesses concludes that litigation and court mandates can play an indispensable role in initiating detracking in schools and districts where such reforms are otherwise unlikely. (SK)

Montana Certification Program Manual.

ERIC Educational Resources Information Center

Montana State Library, Helena.

The Montana Certification Program offers librarians, library staff members, and trustees a systematic and progressive method by which to track their continuing education (CE) efforts; the program also offers library boards and managers an opportunity to recognize staff efforts to improve their skills, ability, and knowledge. This first section of…

Surveying drainage culvert use by carnivores: sampling design and cost-benefit analyzes of track-pads vs. video-surveillance methods.

PubMed

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.

A Protocol for Real-time 3D Single Particle Tracking.

PubMed

Hou, Shangguo; Welsher, Kevin

2018-01-03

Real-time three-dimensional single particle tracking (RT-3D-SPT) has the potential to shed light on fast, 3D processes in cellular systems. Although various RT-3D-SPT methods have been put forward in recent years, tracking high speed 3D diffusing particles at low photon count rates remains a challenge. Moreover, RT-3D-SPT setups are generally complex and difficult to implement, limiting their widespread application to biological problems. This protocol presents a RT-3D-SPT system named 3D Dynamic Photon Localization Tracking (3D-DyPLoT), which can track particles with high diffusive speed (up to 20 µm 2 /s) at low photon count rates (down to 10 kHz). 3D-DyPLoT employs a 2D electro-optic deflector (2D-EOD) and a tunable acoustic gradient (TAG) lens to drive a single focused laser spot dynamically in 3D. Combined with an optimized position estimation algorithm, 3D-DyPLoT can lock onto single particles with high tracking speed and high localization precision. Owing to the single excitation and single detection path layout, 3D-DyPLoT is robust and easy to set up. This protocol discusses how to build 3D-DyPLoT step by step. First, the optical layout is described. Next, the system is calibrated and optimized by raster scanning a 190 nm fluorescent bead with the piezoelectric nanopositioner. Finally, to demonstrate real-time 3D tracking ability, 110 nm fluorescent beads are tracked in water.

Research for the advancement of green chemistry practice: Studies in atmospheric and educational chemistry

NASA Astrophysics Data System (ADS)

Cullipher, Steven Gene

Green chemistry is a philosophy of chemistry that emphasizes a decreasing dependence on limited non-renewable resources and an increasing focus on preventing pollution byproducts of the chemical industry. In short, it is the discipline of chemistry practiced through the lens of environmental stewardship. In an effort to advance the practice of green chemistry, three studies will be described that have ramifications for the practice. The first study examines the atmospheric oxidation of a hydrofluorinated ether, a third-generation CFC replacement compound with primarily unknown atmospheric degradation products. Determination of these products has the potential to impact decisions on refrigerant usage in the future. The second study examines chemistry students' development of understanding benefits-costs-risks analysis when presented with two real-world scenarios: refrigerant choice and fuel choice. By studying how benefits-costs-risks thinking develops, curricular materials and instructional approaches can be designed to better foster the development of an ability that is both necessary for green chemists and important in daily decision-making for non-chemists. The final study uses eye tracking technology to examine students' abilities to interpret molecular properties from structural information in the context of global warming. Such abilities are fundamental if chemists are to appropriately assess risks and hazards of chemistry practice.

Changes in Biology Self-Efficacy during a First-Year University Course

PubMed Central

Ainscough, Louise; Foulis, Eden; Colthorpe, Kay; Zimbardi, Kirsten; Robertson-Dean, Melanie; Chunduri, Prasad; Lluka, Lesley

2016-01-01

Academic self-efficacy encompasses judgments regarding one’s ability to perform academic tasks and is correlated with achievement and persistence. This study describes changes in biology self-efficacy during a first-year course. Students (n = 614) were given the Biology Self-Efficacy Scale at the beginning and end of the semester. The instrument consisted of 21 questions ranking confidence in performing biology-related tasks on a scale from 1 (not at all confident) to 5 (totally confident). The results demonstrated that students increased in self-efficacy during the semester. High school biology and chemistry contributed to self-efficacy at the beginning of the semester; however, this relationship was lost by the end of the semester, when experience within the course became a significant contributing factor. A proportion of high- and low- achieving (24 and 40%, respectively) students had inaccurate self-efficacy judgments of their ability to perform well in the course. In addition, female students were significantly less confident than males overall, and high-achieving female students were more likely than males to underestimate their academic ability. These results suggest that the Biology Self-Efficacy Scale may be a valuable resource for tracking changes in self-efficacy in first-year students and for identifying students with poorly calibrated self-efficacy perceptions. PMID:27193290

Examination of vehicle performance at high speed and high cant deficiency

DOT National Transportation Integrated Search

2011-03-16

In the US, increasing passenger speeds to improve trip time : usually involves increasing speeds through curves. Increasing : speeds through curves will increase the lateral force exerted on : track during curving, thus requiring more intensive track...

Clinical interpretation of the Spinal Cord Injury Functional Index (SCI-FI).

PubMed

Fyffe, Denise; Kalpakjian, Claire Z; Slavin, Mary; Kisala, Pamela; Ni, Pengsheng; Kirshblum, Steven C; Tulsky, David S; Jette, Alan M

2016-09-01

To provide validation of functional ability levels for the Spinal Cord Injury - Functional Index (SCI-FI). Cross-sectional. Inpatient rehabilitation hospital and community settings. A sample of 855 individuals with traumatic spinal cord injury enrolled in 6 rehabilitation centers participating in the National Spinal Cord Injury Model Systems Network. Not Applicable. Spinal Cord Injury-Functional Index (SCI-FI). Cluster analyses identified three distinct groups that represent low, mid-range and high SCI-FI functional ability levels. Comparison of clusters on personal and other injury characteristics suggested some significant differences between groups. These results strongly support the use of SCI-FI functional ability levels to document the perceived functional abilities of persons with SCI. Results of the cluster analysis suggest that the SCI-FI functional ability levels capture function by injury characteristics. Clinical implications regarding tracking functional activity trajectories during follow-up visits are discussed.

Reticle variation influence on manufacturing line and wafer device performance

NASA Astrophysics Data System (ADS)

Nistler, John L.; Spurlock, Kyle

1994-01-01

Cost effective manufacturing of devices at 0.5, 0.35 and 0.25μm geometries will be highly dependent on a companys' ability to obtain an economic return on investment. The high capital investment in equipment and facilities, not to mention the related chemical and wafer costs, for producing 200mm silicon wafers requires aspects of wafer processing to be tightly controlled. Reduction in errors and enhanced yield management requires early correction or avoidance of reticle problems. It is becoming increasingly important to recognize and track all pertinent factors impacting both the technical and financial viability of a wafer manufacturing fabrication area. Reticle related effects on wafer manufacturing can be costly and affect the total quality perceived by the device customer.

Data science, learning, and applications to biomedical and health sciences.

PubMed

Adam, Nabil R; Wieder, Robert; Ghosh, Debopriya

2017-01-01

The last decade has seen an unprecedented increase in the volume and variety of electronic data related to research and development, health records, and patient self-tracking, collectively referred to as Big Data. Properly harnessed, Big Data can provide insights and drive discovery that will accelerate biomedical advances, improve patient outcomes, and reduce costs. However, the considerable potential of Big Data remains unrealized owing to obstacles including a limited ability to standardize and consolidate data and challenges in sharing data, among a variety of sources, providers, and facilities. Here, we discuss some of these challenges and potential solutions, as well as initiatives that are already underway to take advantage of Big Data. © 2017 New York Academy of Sciences.

Moving Toward the Light: Using New Technology to Answer Old Questions

PubMed Central

LUCITTI, JENNIFER L.; DICKINSON, MARY E.

2006-01-01

Fluorescence microscopy has become a principle methodology in the field of developmental biology. Recent technological advances have led to the design of high-speed and high-resolution confocal and multiphoton microscopes that enable researchers to obtain three- and four-dimensional information in living cells and whole embryos. Paralleling this progress, the development of stable and bright vital fluorescent probes has revolutionized the ability to track individual cells in vitro and in vivo and to visualize intercellular and subcellular molecular interactions in real time. Combining imaging modalities and labeling techniques that are increasingly unobtrusive to cell and whole animal function, our understanding of how proteins interact, tissues take form, and organs synchronize to create a functioning animal is reaching a whole new level. PMID:16690954

Impact of Gender on Satisfaction and Confidence in Cholesterol Control Among Veterans at Risk for Cardiovascular Disease.

PubMed

Goldstein, Karen M; Stechuchak, Karen M; Zullig, Leah L; Oddone, Eugene Z; Olsen, Maren K; McCant, Felicia A; Bastian, Lori A; Batch, Bryan C; Bosworth, Hayden B

2017-07-01

Compared with men, women have poorer lipid control. Although potential causes of this disparity have been explored, it is unknown whether patient-centered factors such as satisfaction and confidence contribute. We evaluated (1) whether satisfaction with lipid control and confidence in ability to improve it vary by gender and (2) whether sociodemographic characteristics modify the association. We evaluated baseline survey responses from the Cardiovascular Intervention Improvement Telemedicine Study, including self-rated satisfaction with cholesterol levels and confidence in controlling cholesterol. Participants had poorly controlled hypertension and/or hypercholesterolemia. A total of 428 veterans (15% women) participated. Compared with men, women had higher low-density lipoprotein values at 141.2 versus 121.7 mg/dL, respectively (p < 0.05), higher health literacy, and were less likely to have someone to help track their medications (all p < 0.05). In an adjusted model, women were less satisfied with their cholesterol levels than men with estimated mean scores of 4.3 versus 5.6 on a 1-10 Likert scale (p < 0.05). There was no significant difference in confidence by gender. Participants with support for tracking medications reported higher confidence levels than those without, estimated mean 7.8 versus 7.2 (p < 0.05). Women veterans at high risk for cardiovascular disease were less satisfied with their lipid control than men; however, confidence in ability to improve lipid levels was similar. Veterans without someone to help to track medications were less confident, and women were less likely to have this type of social support. Lack of social support for medication tracking may be a factor in lingering gender-based disparities in hyperlipidemia.

Development of automatic pre-tracking system for fillet weld based on laser trigonometry

NASA Astrophysics Data System (ADS)

Shen, Xiaoqin; Yu, Fusheng

2005-01-01

In this paper, an automatic fillet weld pre-tracking system for welding the work piece of lorry back boards with several bend in haul automobile is developed basing on laser trigonometry. The optical measuring head based on laser-PSD trigonometry is used as position sensor. It is placed in front of the traveling direction of welding wire to get the distances from welding wire to the two side boards of the welding lines, upper board and bottom board of the fillet weld respectively. A chip of AT89S52 is used as the micro controller in this system. The AC servomotors, ball-screws and straight guide rails constitute the sliding table to take welding wire move. The laser-PSD sensors pass through the vertical board, upper board and bottom board of the fillet weld when welding wire moves and then get the distance. The laser-PSD sensors output the analog signals. After A/D conversion, the digital signal is input into AT89S52 and calculated. Then the information of the position and lateral deviation of the welding wire when welding a certain position are gotten to control welding wires. So the weld pre-tracking for welding the work piece with long distance and large bend in haul automobile is realized. The position information is input into EEPROM to be saved for short time after handled by AT89S52. The information is as the welding position information as well as the speed adjusting data of the welding wire when it welds the several bend of the work piece. The practice indicates that this system has high pre-tracking precision, good anti-disturb ability, excellent reliability, easy operating ability and good adaptability to the field of production.

1,3-Bis(2-chloroethyl)-1-nitrosourea-loaded bovine serum albumin nanoparticles with dual magnetic resonance-fluorescence imaging for tracking of chemotherapeutic agents.

PubMed

Wei, Kuo-Chen; Lin, Feng-Wei; Huang, Chiung-Yin; Ma, Chen-Chi M; Chen, Ju-Yu; Feng, Li-Ying; Yang, Hung-Wei

To date, knowing how to identify the location of chemotherapeutic agents in the human body after injection is still a challenge. Therefore, it is urgent to develop a drug delivery system with molecular imaging tracking ability to accurately understand the distribution, location, and concentration of a drug in living organisms. In this study, we developed bovine serum albumin (BSA)-based nanoparticles (NPs) with dual magnetic resonance (MR) and fluorescence imaging modalities (fluorescein isothiocyanate [FITC]-BSA-Gd/1,3-bis(2-chloroethyl)-1-nitrosourea [BCNU] NPs) to deliver BCNU for inhibition of brain tumor cells (MBR 261-2). These BSA-based NPs are water dispersible, stable, and biocompatible as confirmed by XTT cell viability assay. In vitro phantoms and in vivo MR and fluorescence imaging experiments show that the developed FITC-BSA-Gd/BCNU NPs enable dual MR and fluorescence imaging for monitoring cellular uptake and distribution in tumors. The T1 relaxivity (R1) of FITC-BSA-Gd/BCNU NPs was 3.25 mM(-1) s(-1), which was similar to that of the commercial T1 contrast agent (R1 =3.36 mM(-1) s(-1)). The results indicate that this multifunctional drug delivery system has potential bioimaging tracking of chemotherapeutic agents ability in vitro and in vivo for cancer therapy.

WeaVR: a self-contained and wearable immersive virtual environment simulation system.

PubMed

Hodgson, Eric; Bachmann, Eric R; Vincent, David; Zmuda, Michael; Waller, David; Calusdian, James

2015-03-01

We describe WeaVR, a computer simulation system that takes virtual reality technology beyond specialized laboratories and research sites and makes it available in any open space, such as a gymnasium or a public park. Novel hardware and software systems enable HMD-based immersive virtual reality simulations to be conducted in any arbitrary location, with no external infrastructure and little-to-no setup or site preparation. The ability of the WeaVR system to provide realistic motion-tracked navigation for users, to improve the study of large-scale navigation, and to generate usable behavioral data is shown in three demonstrations. First, participants navigated through a full-scale virtual grocery store while physically situated in an open grass field. Trajectory data are presented for both normal tracking and for tracking during the use of redirected walking that constrained users to a predefined area. Second, users followed a straight path within a virtual world for distances of up to 2 km while walking naturally and being redirected to stay within the field, demonstrating the ability of the system to study large-scale navigation by simulating virtual worlds that are potentially unlimited in extent. Finally, the portability and pedagogical implications of this system were demonstrated by taking it to a regional high school for live use by a computer science class on their own school campus.

Accuracy and trending ability of the fourth-generation FloTrac/Vigileo System™ in patients undergoing abdominal aortic aneurysm surgery.

PubMed

Maeda, Takuma; Hattori, Kohshi; Sumiyoshi, Miho; Kanazawa, Hiroko; Ohnishi, Yoshihiko

2018-06-01

The fourth-generation FloTrac/Vigileo™ improved its algorithm to follow changes in systemic vascular resistance index (SVRI). This revision may improve the accuracy and trending ability of CI even in patients who undergo abdominal aortic aneurysm (AAA) surgery which cause drastic change of SVRI by aortic clamping. The purpose of this study is to elucidate the accuracy and trending ability of the fourth-generation FloTrac/Vigileo™ in patients with AAA surgery by comparing the FloTrac/Vigileo™-derived CI (CI FT ) with that measured by three-dimensional echocardiography (CI 3D ). Twenty-six patients undergoing elective AAA surgery were included in this study. CI FT and CI3 D were determined simultaneously in eight points including before and after aortic clamp. We used CI 3D as the reference method. In the Bland-Altman analysis, CI FT had a wide limit of agreement with CI 3D showing a percentage error of 46.7%. Subgroup analysis showed that the percentage error between CO 3D and CO FT was 56.3% in patients with cardiac index < 2.5 L/min/m 2 and 28.4% in patients with cardiac index ≥ 2.5 L/min/m 2 . SVRI was significantly higher in patients with cardiac index < 2.5 L/min/m 2 (1703 ± 330 vs. 2757 ± 798; p < 0.001). The tracking ability of fourth generation of FloTrac/Vigileo™ after aortic clamp was not clinically acceptable (26.9%). The degree of accuracy of the fourth-generation FloTrac/Vigileo™ in patients with AAA surgery was not acceptable. The tracking ability of the fourth-generation FloTrac/Vigileo™ after aortic clamp was below the acceptable limit.

Investigation of the relative orientation of the system of optical sensors to monitor the technosphere objects

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.

More rapid climate change promotes evolutionary rescue through selection for increased dispersal distance

PubMed Central

Boeye, Jeroen; Travis, Justin M J; Stoks, Robby; Bonte, Dries

2013-01-01

Species can either adapt to new conditions induced by climate change or shift their range in an attempt to track optimal environmental conditions. During current range shifts, species are simultaneously confronted with a second major anthropogenic disturbance, landscape fragmentation. Using individual-based models with a shifting climate window, we examine the effect of different rates of climate change on the evolution of dispersal distances through changes in the genetically determined dispersal kernel. Our results demonstrate that the rate of climate change is positively correlated to the evolved dispersal distances although too fast climate change causes the population to crash. When faced with realistic rates of climate change, greater dispersal distances evolve than those required for the population to keep track of the climate, thereby maximizing population size. Importantly, the greater dispersal distances that evolve when climate change is more rapid, induce evolutionary rescue by facilitating the population in crossing large gaps in the landscape. This could ensure population persistence in case of range shifting in fragmented landscapes. Furthermore, we highlight problems in using invasion speed as a proxy for potential range shifting abilities under climate change. PMID:23467649

How can present and future satellite missions support scientific studies that address ocean acidification?

USGS Publications Warehouse

Salisbury, Joseph; Vandemark, Douglas; Jonsson, Bror; Balch, William; Chakraborty, Sumit; Lohrenz, Steven; Chapron, Bertrand; Hales, Burke; Mannino, Antonio; Mathis, Jeremy T.; Reul, Nicolas; Signorini, Sergio; Wanninkhof, Rik; Yates, Kimberly K.

2016-01-01

Space-based observations offer unique capabilities for studying spatial and temporal dynamics of the upper ocean inorganic carbon cycle and, in turn, supporting research tied to ocean acidification (OA). Satellite sensors measuring sea surface temperature, color, salinity, wind, waves, currents, and sea level enable a fuller understanding of a range of physical, chemical, and biological phenomena that drive regional OA dynamics as well as the potentially varied impacts of carbon cycle change on a broad range of ecosystems. Here, we update and expand on previous work that addresses the benefits of space-based assets for OA and carbonate system studies. Carbonate chemistry and the key processes controlling surface ocean OA variability are reviewed. Synthesis of present satellite data streams and their utility in this arena are discussed, as are opportunities on the horizon for using new satellite sensors with increased spectral, temporal, and/or spatial resolution. We outline applications that include the ability to track the biochemically dynamic nature of water masses, to map coral reefs at higher resolution, to discern functional phytoplankton groups and their relationships to acid perturbations, and to track processes that contribute to acid variation near the land-ocean interface.

Labeling of neuronal differentiation and neuron cells with biocompatible fluorescent nanodiamonds

PubMed Central

Hsu, Tzu-Chia; Liu, Kuang-Kai; Chang, Huan-Cheng; Hwang, Eric; Chao, Jui-I

2014-01-01

Nanodiamond is a promising carbon nanomaterial developed for biomedical applications. Here, we show fluorescent nanodiamond (FND) with the biocompatible properties that can be used for the labeling and tracking of neuronal differentiation and neuron cells derived from embryonal carcinoma stem (ECS) cells. The fluorescence intensities of FNDs were increased by treatment with FNDs in both the mouse P19 and human NT2/D1 ECS cells. FNDs were taken into ECS cells; however, FNDs did not alter the cellular morphology and growth ability. Moreover, FNDs did not change the protein expression of stem cell marker SSEA-1 of ECS cells. The neuronal differentiation of ECS cells could be induced by retinoic acid (RA). Interestingly, FNDs did not affect on the morphological alteration, cytotoxicity and apoptosis during the neuronal differentiation. Besides, FNDs did not alter the cell viability and the expression of neuron-specific marker β-III-tubulin in these differentiated neuron cells. The existence of FNDs in the neuron cells can be identified by confocal microscopy and flow cytometry. Together, FND is a biocompatible and readily detectable nanomaterial for the labeling and tracking of neuronal differentiation process and neuron cells from stem cells. PMID:24830447

Labeling of neuronal differentiation and neuron cells with biocompatible fluorescent nanodiamonds.

PubMed

Hsu, Tzu-Chia; Liu, Kuang-Kai; Chang, Huan-Cheng; Hwang, Eric; Chao, Jui-I

2014-05-16

Nanodiamond is a promising carbon nanomaterial developed for biomedical applications. Here, we show fluorescent nanodiamond (FND) with the biocompatible properties that can be used for the labeling and tracking of neuronal differentiation and neuron cells derived from embryonal carcinoma stem (ECS) cells. The fluorescence intensities of FNDs were increased by treatment with FNDs in both the mouse P19 and human NT2/D1 ECS cells. FNDs were taken into ECS cells; however, FNDs did not alter the cellular morphology and growth ability. Moreover, FNDs did not change the protein expression of stem cell marker SSEA-1 of ECS cells. The neuronal differentiation of ECS cells could be induced by retinoic acid (RA). Interestingly, FNDs did not affect on the morphological alteration, cytotoxicity and apoptosis during the neuronal differentiation. Besides, FNDs did not alter the cell viability and the expression of neuron-specific marker β-III-tubulin in these differentiated neuron cells. The existence of FNDs in the neuron cells can be identified by confocal microscopy and flow cytometry. Together, FND is a biocompatible and readily detectable nanomaterial for the labeling and tracking of neuronal differentiation process and neuron cells from stem cells.

Influence of laser irradiation on deposition characteristics of cold sprayed Stellite-6 coatings

NASA Astrophysics Data System (ADS)

Li, Bo; Jin, Yan; Yao, Jianhua; Li, Zhihong; Zhang, Qunli; Zhang, Xin

2018-03-01

Depositing hard materials such as Stellite-6 solely by cold spray (CS) is challengeable due to limited ability of plastic deformation. In this study, the deposition of Stellite-6 powder was achieved by supersonic laser deposition (SLD) which combines CS with synchronous laser irradiation. The surface morphology, deposition efficiency, track shape of Stellite-6 coatings produced over a range of laser irradiation temperatures were examined so as to reveal the effects of varying laser energy inputting on the deposition process of high strength material. The microstructure, phase composition and wear/corrosion resistant properties of the as-deposited Stellite-6 coatings were also investigated. The experimental results demonstrate that the surface flatness and deposition efficiency increase with laser irradiation temperature due to the softening effect induced by laser heating. The as-deposited Stellite-6 tracks show asymmetric shapes which are influenced by the relative configuration of powder stream and laser beam. The SLD coatings can preserve the original microstructure and phase of the feedstock material due to relatively low laser energy inputting, which result in the superior wear/corrosion resistant properties as compared to the counterpart prepared by laser cladding.

Virtual Superheroes: Using Superpowers in Virtual Reality to Encourage Prosocial Behavior

PubMed Central

Rosenberg, Robin S.; Baughman, Shawnee L.; Bailenson, Jeremy N.

2013-01-01

Background Recent studies have shown that playing prosocial video games leads to greater subsequent prosocial behavior in the real world. However, immersive virtual reality allows people to occupy avatars that are different from them in a perceptually realistic manner. We examine how occupying an avatar with the superhero ability to fly increases helping behavior. Principal Findings Using a two-by-two design, participants were either given the power of flight (their arm movements were tracked to control their flight akin to Superman’s flying ability) or rode as a passenger in a helicopter, and were assigned one of two tasks, either to help find a missing diabetic child in need of insulin or to tour a virtual city. Participants in the “super-flight” conditions helped the experimenter pick up spilled pens after their virtual experience significantly more than those who were virtual passengers in a helicopter. Conclusion The results indicate that having the “superpower” of flight leads to greater helping behavior in the real world, regardless of how participants used that power. A possible mechanism for this result is that having the power of flight primed concepts and prototypes associated with superheroes (e.g., Superman). This research illustrates the potential of using experiences in virtual reality technology to increase prosocial behavior in the physical world. PMID:23383029

Development of early handwriting: Visual-motor control during letter copying.

PubMed

Maldarelli, Jennifer E; Kahrs, Björn A; Hunt, Sarah C; Lockman, Jeffrey J

2015-07-01

Despite the importance of handwriting for school readiness and early academic progress, prior research on the development of handwriting has focused primarily on the product rather than the process by which young children write letters. In contrast, in the present work, early handwriting is viewed as involving a suite of perceptual, motor, and cognitive abilities, which must work in unison if children are to write letters efficiently. To study such coordination, head-mounted eye-tracking technology was used to investigate the process of visual-motor coordination while kindergarten children (N = 23) and adults (N = 11) copied individual letters and strings of letters that differed in terms of their phonemic properties. Results indicated that kindergarten children were able to copy single letters efficiently, as did adults. When the cognitive demands of the task increased and children were presented with strings of letters, however, their ability to copy letters efficiently was compromised: Children frequently interrupted their writing midletter, whereas they did not do so on single letter trials. Yet, with increasing age, children became more efficient in copying letter strings, in part by using vision more prospectively when writing. Taken together, the results illustrate how the coordination of perceptual, motor, and cognitive processes contributes to advances in the development of letter writing skill. (c) 2015 APA, all rights reserved).

Multifunctional nanomedicine platform for concurrent delivery of chemotherapeutic drugs and mild hyperthermia to ovarian cancer cells.

PubMed

Taratula, Olena; Dani, Raj Kumar; Schumann, Canan; Xu, Hong; Wang, Andrew; Song, Han; Dhagat, Pallavi; Taratula, Oleh

2013-12-15

A multifunctional tumor-targeting delivery system was developed and evaluated for an efficient treatment of drug-resistant ovarian cancer by combinatorial therapeutic modality based on chemotherapy and mild hyperthermia. The engineered iron oxide nanoparticle (IONPs)-based nanocarrier served as an efficient delivery vehicle for doxorubicin and provided the ability to heat cancer cells remotely upon exposure to an alternating magnetic field (AMF). The nanocarrier was additionally modified with polyethylene glycol and LHRH peptide to improve its biocompatibility and ability to target tumor cells. The synthesized delivery system has an average size of 97.1 nm and a zeta potential close to zero, both parameters favorable for increased stability in biological media and decreased elimination by the immune system. The nanocarrier demonstrated faster drug release in acidic conditions that mimic the tumor environment. It was also observed that the LHRH targeted delivery system could effectively enter drug resistant ovarian cancer cells, and the fate of doxorubicin was tracked with fluorescence microscope. Mild hyperthermia (40°C) generated by IONPs under exposure to AMF synergistically increased the cytotoxicity of doxorubicin delivered by the developed nanocarrier to cancer cells. Thus, the developed IONPs-based delivery system has high potential in the effective treatment of ovarian cancer by combinatorial approach. Copyright © 2013 Elsevier B.V. All rights reserved.

Development of Early Handwriting: Visual-Motor Control During Letter Copying

PubMed Central

Maldarelli, Jennifer E.; Kahrs, Björn A.; Hunt, Sarah C.; Lockman, Jeffrey J.

2015-01-01

Despite the importance of handwriting for school readiness and early academic progress, prior research on the development of handwriting has focused primarily on the product rather than the process by which young children write letters. In contrast, in the present work, early handwriting is viewed as involving a suite of perceptual, motor and cognitive abilities, which must work in unison if children are to write letters efficiently. To study such coordination, head-mounted eye-tracking technology was used to investigate the process of visual-motor coordination while kindergarten children (N=23) and adults (N=11) copied individual letters and strings of letters that differed in terms of their phonemic properties. Results indicated that kindergarten children were able to copy single letters efficiently, as did adults. When the cognitive demands of the task increased and children were presented with strings of letters, however, their ability to copy letters efficiently was compromised: children frequently interrupted their writing mid-letter, whereas they did not do so on single letter trials. Yet, with increasing age, children became more efficient in copying letter strings, in part by using vision more prospectively when writing. Taken together, the results illustrate how the coordination of perceptual, motor and cognitive processes contributes to advances in the development of letter writing skill. PMID:26029821

Application of a tri-axial accelerometry-based portable motion recorder for the quantitative assessment of hippotherapy in children and adolescents with cerebral palsy

PubMed Central

Mutoh, Tomoko; Mutoh, Tatsushi; Takada, Makoto; Doumura, Misato; Ihara, Masayo; Taki, Yasuyuki; Tsubone, Hirokazu; Ihara, Masahiro

2016-01-01

[Purpose] This case series aims to evaluate the effects of hippotherapy on gait and balance ability of children and adolescents with cerebral palsy using quantitative parameters for physical activity. [Subjects and Methods] Three patients with gait disability as a sequela of cerebral palsy (one female and two males; age 5, 12, and 25 years old) were recruited. Participants received hippotherapy for 30 min once a week for 2 years. Gait parameters (step rate, step length, gait speed, mean acceleration, and horizontal/vertical displacement ratio) were measured using a portable motion recorder equipped with a tri-axial accelerometer attached to the waist before and after a 10-m walking test. [Results] There was a significant increase in step length between before and after a single hippotherapy session. Over the course of 2 year intervention, there was a significant increase in step rate, gait speed, step length, and mean acceleration and a significant improvement in horizontal/vertical displacement ratio. [Conclusion] The data suggest that quantitative parameters derived from a portable motion recorder can track both immediate and long-term changes in the walking ability of children and adolescents with cerebral palsy undergoing hippotherapy. PMID:27821971

Effects of hypercapnia and bedrest on psychomotor performance

NASA Technical Reports Server (NTRS)

Storm, W. F.; Giannetta, C. L.

1974-01-01

Two weeks of continuous exposure to simulated weightlessness (bedrest) and/or an elevated (30 torr) CO2 environment had no detrimental effect on complex tracking performance, eye-hand coordination, or problem-solving ability. These results were consistent with previously reported behavioral findings which investigated these two factors only as independent stressors.

Essays on Child Development in Developing Countries

ERIC Educational Resources Information Center

Humpage, Sarah Davidson

2013-01-01

This dissertation presents the results of three field experiments implemented to evaluate the effectiveness of strategies to improve the health or education of children in developing countries. In Guatemala, community health workers at randomly selected clinics were given patient tracking lists to improve their ability to remind parents when their…

Linking Infants' Distributional Learning Abilities to Natural Language Acquisition

ERIC Educational Resources Information Center

van Heugten, Marieke; Johnson, Elizabeth K.

2010-01-01

This study examines the link between distributional patterns in the input and infants' acquisition of non-adjacent dependencies. In two Headturn Preference experiments, Dutch-learning 24-month-olds (but not 17-month-olds) were found to track the remote dependency between the definite article "het" and the diminutive suffix…

Sweden/Michigan naturalistic field operational test - phase 1 : benefits of origin and destination information in IntelliDrive data sets

DOT National Transportation Integrated Search

2009-06-01

Trip origin and destination (OD) data plays a crucial role in various transportation activities. This information not : only includes the starting and end points of a trip, but also information that can be obtained through the ability to : track v...

Quantitative Endoscopic Phototransducer Investigation of Normal Velopharyngeal Physiology

ERIC Educational Resources Information Center

Karnell, Michael P.; Moon, Jerald B.; Nakajima, Kengo; Kacmarynski, Deborah S.

2016-01-01

Purpose: The purpose of this research was to learn the extent to which healthy individuals vary in their ability to achieve velopharyngeal closure for speech. Method: Twenty healthy adult volunteers (10 women, 10 men) were tested using an endoscopic phototransducer system that tracks variations in velopharyngeal closure during speech production.…

TSCA Environmental Release Application (TERA) for Pseudomonas fluorescens strains HK44 and 5RL

EPA Pesticide Factsheets

TERAs submitted by the University of Tennessee and Micro Systems Technologies, LLC and given the tracking designation of R-04-01 and R-04-02. The strain will be tested to examine its ability to detect and monitor naphthalene and methyl salicylate.

Probabilistic Cue Combination: Less Is More

ERIC Educational Resources Information Center

Yurovsky, Daniel; Boyer, Ty W.; Smith, Linda B.; Yu, Chen

2013-01-01

Learning about the structure of the world requires learning probabilistic relationships: rules in which cues do not predict outcomes with certainty. However, in some cases, the ability to track probabilistic relationships is a handicap, leading adults to perform non-normatively in prediction tasks. For example, in the "dilution effect,"…

Learning Words from Speakers with False Beliefs

ERIC Educational Resources Information Center

Papafragou, Anna; Fairchild, Sarah; Cohen, Matthew L.; Friedberg, Carlyn

2017-01-01

During communication, hearers try to infer the speaker's intentions to be able to understand what the speaker means. Nevertheless, whether (and how early) preschoolers track their interlocutors' mental states is still a matter of debate. Furthermore, there is disagreement about how children's ability to consult a speaker's belief in communicative…

The Effect of E-Portal System on Corporate Image of Universities

ERIC Educational Resources Information Center

Tunji, Oyedepo; Nelson, Okorie

2011-01-01

Internet connectivity in tertiary institutions in Africa has been summarized in three characteristics-- too little, too expensive and poorly managed (African Tertiary Institutions Connectivity Survey (ATICS), 2006 report). The Internet portal system offers educational organizations the ability to track students needs and promote their programs and…

Guaranteed LiDAR-aided multi-object tracking at road intersections : USDOT Region V Regional University Transportation Center final report.

DOT National Transportation Integrated Search

2016-12-21

The ability to accurately measure and cost-effectively collect traffic data at road intersections is needed to improve their safety and operations. This study investigates the feasibility of using laser ranging technology (LiDAR) for this purpose. Th...

77 FR 34004 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-08

... incidence rates, annual injury frequencies, and descriptive injury information for children under the age of... and descriptive injury information for farm operators and their employees 20 years of age or older... information is not collected, NIOSH's ability to track and evaluate the impact of its injury prevention...

Stereoscopic video analysis of Anopheles gambiae behavior in the field: challenges and opportunities

USDA-ARS?s Scientific Manuscript database

Advances in our ability to localize and track individual swarming mosquitoes in the field via stereoscopic image analysis have enabled us to test long standing ideas about individual male behavior and directly observe coupling. These studies further our fundamental understanding of the reproductive ...

The Development of Technological Competence from Adolescence to Adulthood

ERIC Educational Resources Information Center

Autio, Ossi

2011-01-01

This article builds on earlier research that defined and assessed technological competence among adolescents. It tracks students who took part in a measurements of technical abilities study fifteen years ago. The researcher had no previous knowledge of the test subjects' current employment status, but in favorable circumstances, these test…

77 FR 43740 - Changes to the In-Bond Process; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-26

... various changes to the in-bond regulations to enhance CBP's ability to regulate and track in-bond...-bond merchandise is exported. In that document, CBP published a summary of its analysis under the Regulatory Flexibility Act and stated that the complete Initial Regulatory Flexibility Analysis (IRFA) was...

United States Transportation Command (USTRANSCOM) 2008 Annual Report

DTIC Science & Technology

2008-01-01

enthusiastic about the potential offered by AIT. The DOD currently has the largest active RFID ( aRFID ) system in the world. It provides the ability...to develop the satellite tracking business case for those situations where the aRFID infrastructure is less robust or nonexistent. USTRANSCOM is also

Bats track and exploit changes in insect pest populations

USDA-ARS?s Scientific Manuscript database

The role of bats or any generalist predator in suppressing prey populations depends on the predator’s ability to exploit available prey in space and time. Using a qPCR faecal DNA assay, we document significant association between numbers of Brazilian free-tailed bats (Tadarida brasiliensis) consumin...

75 FR 76479 - Notice of Proposed Information Collection for Public Comment: County Data Record Project

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-08

... Associates Inc. and its subcontractors, Fairview Industries and Smart Data Strategies, is conducting a... activities. First, this database will give HUD an ability to track home sales, foreclosures and tax... programs such as the Neighborhood Stabilization Program (NSP), the HOME Investment Partnership Program, and...

Equity in the Classroom

ERIC Educational Resources Information Center

DiMartino, Joseph; Miles, Sherri

2004-01-01

In this article, the authors discuss three reform strategies designed to produce educational equity. The first strategy, heterogeneous grouping, does away with the controversial practice of placing students in different tracks based on their ability, which can polarize the student population into pro- and anti-school camps, create a "caste system"…

Adaptive Tracking Control for Robots With an Interneural Computing Scheme.

PubMed

Tsai, Feng-Sheng; Hsu, Sheng-Yi; Shih, Mau-Hsiang

2018-04-01

Adaptive tracking control of mobile robots requires the ability to follow a trajectory generated by a moving target. The conventional analysis of adaptive tracking uses energy minimization to study the convergence and robustness of the tracking error when the mobile robot follows a desired trajectory. However, in the case that the moving target generates trajectories with uncertainties, a common Lyapunov-like function for energy minimization may be extremely difficult to determine. Here, to solve the adaptive tracking problem with uncertainties, we wish to implement an interneural computing scheme in the design of a mobile robot for behavior-based navigation. The behavior-based navigation adopts an adaptive plan of behavior patterns learning from the uncertainties of the environment. The characteristic feature of the interneural computing scheme is the use of neural path pruning with rewards and punishment interacting with the environment. On this basis, the mobile robot can be exploited to change its coupling weights in paths of neural connections systematically, which can then inhibit or enhance the effect of flow elimination in the dynamics of the evolutionary neural network. Such dynamical flow translation ultimately leads to robust sensory-to-motor transformations adapting to the uncertainties of the environment. A simulation result shows that the mobile robot with the interneural computing scheme can perform fault-tolerant behavior of tracking by maintaining suitable behavior patterns at high frequency levels.

Understanding the Full-Time, Non-Tenure-Track Faculty Appointment

ERIC Educational Resources Information Center

Carlucci, Pandora Grewe

2013-01-01

This dissertation explores the socialization of full-time, non-tenure-track (FTNTT) faculty members at two U.S. urban, public research universities. The increase in the use of non-tenure-track faculty appointments has been driven by the need to maximize the use of limited resources, while at the same time, address the need for increases in…

Moving Uphill: Microbial Facilitation at the Leading Edge of Plant Species Distributional Shifts

NASA Astrophysics Data System (ADS)

Suding, K.; Farrer, E.; Spasojevic, M.; Porazinska, D.; Bueno de Mesquita, C.; Schmidt, S. K.

2016-12-01

Climate change is expected to influence species distributions and reshuffle patterns of biodiversity. A key challenge to our understanding of these effects is that biotic interactions - new species to compete with, new stressors that increase dependence on facilitation, new prey or predators - will likely affect the ability of species to track climate at the leading edges of their distributional range. While it is well established that soil biota strongly influence plant abundance and diversity, it has been difficult to quantify the key belowground dynamics. This presentation will investigate the influence of one key biotic interaction, between plants and soil microbiota, on the ability of plant species to track climate change and expand their range uphill in a high montane system in the Front Range of Colorado. High-resolution photography from 1972 and 2008 indicate colonization of tundra vegetation in formerly unvegetated areas. Observational work on the distributions patterns of both plants and soil microbiota (bacteria, fungi and nematodes) in a spatially-explicit grid at the upper edge of plant distributions indicate strong, mostly positive, associations between plant species and soil taxa. Abiotic factors, while important, consistently underpredicted the occurrence of plant species and, in nine of the 12 most common tundra plants, co-occurring microbial taxa were important predictors of plant occurrence. Comparison of plant and microbial distributional patterns in 2007 and 2015 indicate the influence of microbial community composition on assembly and beta-diversity of the plant community over time. Plant colonization patterns in this region previously devoid of vegetation will likely influence carbon, nitrogen and phosphorus dynamics, with downstream consequences on nutrient limitation and phytoplankton composition in alpine lakes.

Reflector control technology in space laser communication

NASA Astrophysics Data System (ADS)

Xie, Meilin; Ma, Caiwen; Yao, Cheng; Huang, Wei; Lian, Xuezheng; Feng, Xubin; Jing, Feng

2017-11-01

The optical frequencies band is used as information carrier to realize laser communication between two low-orbit micro-satellites in space which equipped with inter-satellite laser communication terminals, optical switches, space routers and other payload. The laser communication terminal adopts a two-dimensional turntable with a single mirror structure. In this paper, the perturbation model of satellite platform is established in this paper. The relationship between the coupling and coordinate transformation of satellite disturbance is analyzed and the laser pointing vector is deduced. Using the tracking differentiator to speed up the circular grating angle information constitute speed loop feedback, which avoids the problem of error amplification caused by the high frequency of the conventional difference algorithm. Finally, the suppression ability of the satellite platform disturbance and the tracking accuracy of the tracking system are simulated and analyzed. The results show that the tracking accuracy of the whole system is 10μrad in the case of satellite vibration, which provides the basis for the optimization of the performance of the space-borne laser communication control system.

BORC Functions Upstream of Kinesins 1 and 3 to Coordinate Regional Movement of Lysosomes along Different Microtubule Tracks.

PubMed

Guardia, Carlos M; Farías, Ginny G; Jia, Rui; Pu, Jing; Bonifacino, Juan S

2016-11-15

The multiple functions of lysosomes are critically dependent on their ability to undergo bidirectional movement along microtubules between the center and the periphery of the cell. Centrifugal and centripetal movement of lysosomes is mediated by kinesin and dynein motors, respectively. We recently described a multi-subunit complex named BORC that recruits the small GTPase Arl8 to lysosomes to promote their kinesin-dependent movement toward the cell periphery. Here, we show that BORC and Arl8 function upstream of two structurally distinct kinesin types: kinesin-1 (KIF5B) and kinesin-3 (KIF1Bβ and KIF1A). Remarkably, KIF5B preferentially moves lysosomes on perinuclear tracks enriched in acetylated α-tubulin, whereas KIF1Bβ and KIF1A drive lysosome movement on more rectilinear, peripheral tracks enriched in tyrosinated α-tubulin. These findings establish BORC as a master regulator of lysosome positioning through coupling to different kinesins and microtubule tracks. Common regulation by BORC enables coordinate control of lysosome movement in different regions of the cell. Published by Elsevier Inc.

BORC Functions Upstream of Kinesins 1 and 3 to Coordinate Regional Movement of Lysosomes Along Different Microtubule Tracks

PubMed Central

Guardia, Carlos M.; Farías, Ginny G.; Jia, Rui; Pu, Jing; Bonifacino, Juan S.

2016-01-01

Summary The multiple functions of lysosomes are critically dependent on their ability to undergo bidirectional movement along microtubules between the center and the periphery of the cell. Centrifugal and centripetal movement of lysosomes is mediated by kinesin and dynein motors, respectively. We recently described a multisubunit complex named BORC that recruits the small GTPase Arl8 to lysosomes to promote their kinesin-dependent movement toward the cell periphery. Here we show that BORC and Arl8 function upstream of two structurally distinct kinesin types: kinesin-1 (KIF5B) and kinesin-3 (KIF1Bβ and KIF1A). Remarkably, KIF5B preferentially moves lysosomes on perinuclear tracks enriched in acetylated α-tubulin, whereas KIF1Bβ and KIF1A drive lysosome movement on more rectilinear, peripheral tracks enriched in tyrosinated α-tubulin. These findings establish BORC as a master regulator of lysosome positioning through coupling to different kinesins and microtubule tracks. Common regulation by BORC enables coordinate control of lysosome movement in different regions of the cell. PMID:27851960

Tracking instrument and control for solar concentrators. Final technical report, October 1979-January 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, J; Kuhlman, J

1981-01-31

The tracker uses a single photo sensor, and a rotating aperature to obtain tracking accuracies better than 1.5 mrads (0.1 degs). Peak signal detection is used to eliminate tracking of false sources, i.e., clouds, etc. A prism is employed to obtain an extended field of view (150 degs axially - 360 degs radially). The tracker digitally measures the Suns displacement angle relative to the concentrator axis, and repositions it incrementally. This arrangement permits the use of low cost non-servo motors. The local controller contains microprocessor based electronics, incorporating digital signal processing. A single controller may be time shared by amore » maximum of sixteen trackers, providing a high performance, cost effective solar tracking system, suitable for both line and point focus concentrators. An installation may have the local controller programmed as a standalone unit or slaved to a central controller. When used with a central controller, dynamic data monitoring and logging is available, together with the ability to change system modes and parameters, as desired.« less

Teleoperation of Robonaut Using Finger Tracking

NASA Technical Reports Server (NTRS)

Champoux, Rachel G.; Luo, Victor

2012-01-01

With the advent of new finger tracking systems, the idea of a more expressive and intuitive user interface is being explored and implemented. One practical application for this new kind of interface is that of teleoperating a robot. For humanoid robots, a finger tracking interface is required due to the level of complexity in a human-like hand, where a joystick isn't accurate. Moreover, for some tasks, using one's own hands allows the user to communicate their intentions more effectively than other input. The purpose of this project was to develop a natural user interface for someone to teleoperate a robot that is elsewhere. Specifically, this was designed to control Robonaut on the international space station to do tasks too dangerous and/or too trivial for human astronauts. This interface was developed by integrating and modifying 3Gear's software, which includes a library of gestures and the ability to track hands. The end result is an interface in which the user can manipulate objects in real time in the user interface. then, the information is relayed to a simulator, the stand in for Robonaut, at a slight delay.

Eye Tracking and Head Movement Detection: A State-of-Art Survey

PubMed Central

2013-01-01

Eye-gaze detection and tracking have been an active research field in the past years as it adds convenience to a variety of applications. It is considered a significant untraditional method of human computer interaction. Head movement detection has also received researchers' attention and interest as it has been found to be a simple and effective interaction method. Both technologies are considered the easiest alternative interface methods. They serve a wide range of severely disabled people who are left with minimal motor abilities. For both eye tracking and head movement detection, several different approaches have been proposed and used to implement different algorithms for these technologies. Despite the amount of research done on both technologies, researchers are still trying to find robust methods to use effectively in various applications. This paper presents a state-of-art survey for eye tracking and head movement detection methods proposed in the literature. Examples of different fields of applications for both technologies, such as human-computer interaction, driving assistance systems, and assistive technologies are also investigated. PMID:27170851

A data processing method based on tracking light spot for the laser differential confocal component parameters measurement system

NASA Astrophysics Data System (ADS)

Shao, Rongjun; Qiu, Lirong; Yang, Jiamiao; Zhao, Weiqian; Zhang, Xin

2013-12-01

We have proposed the component parameters measuring method based on the differential confocal focusing theory. In order to improve the positioning precision of the laser differential confocal component parameters measurement system (LDDCPMS), the paper provides a data processing method based on tracking light spot. To reduce the error caused by the light point moving in collecting the axial intensity signal, the image centroiding algorithm is used to find and track the center of Airy disk of the images collected by the laser differential confocal system. For weakening the influence of higher harmonic noises during the measurement, Gaussian filter is used to process the axial intensity signal. Ultimately the zero point corresponding to the focus of the objective in a differential confocal system is achieved by linear fitting for the differential confocal axial intensity data. Preliminary experiments indicate that the method based on tracking light spot can accurately collect the axial intensity response signal of the virtual pinhole, and improve the anti-interference ability of system. Thus it improves the system positioning accuracy.

On-Line Identification of Simulation Examples for Forgetting Methods to Track Time Varying Parameters Using the Alternative Covariance Matrix in Matlab

NASA Astrophysics Data System (ADS)

Vachálek, Ján

2011-12-01

The paper compares the abilities of forgetting methods to track time varying parameters of two different simulated models with different types of excitation. The observed parameters in the simulations are the integral sum of the Euclidean norm, deviation of the parameter estimates from their true values and a selected band prediction error count. As supplementary information, we observe the eigenvalues of the covariance matrix. In the paper we used a modified method of Regularized Exponential Forgetting with Alternative Covariance Matrix (REFACM) along with Directional Forgetting (DF) and three standard regularized methods.

The Application of Leap Motion in Astronaut Virtual Training

NASA Astrophysics Data System (ADS)

Qingchao, Xie; Jiangang, Chao

2017-03-01

With the development of computer vision, virtual reality has been applied in astronaut virtual training. As an advanced optic equipment to track hand, Leap Motion can provide precise and fluid tracking of hands. Leap Motion is suitable to be used as gesture input device in astronaut virtual training. This paper built an astronaut virtual training based Leap Motion, and established the mathematics model of hands occlusion. At last the ability of Leap Motion to handle occlusion was analysed. A virtual assembly simulation platform was developed for astronaut training, and occlusion gesture would influence the recognition process. The experimental result can guide astronaut virtual training.

Commissioning of the ATLAS pixel detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

ATLAS Collaboration; Golling, Tobias

2008-09-01

The ATLAS pixel detector is a high precision silicon tracking device located closest to the LHC interaction point. It belongs to the first generation of its kind in a hadron collider experiment. It will provide crucial pattern recognition information and will largely determine the ability of ATLAS to precisely track particle trajectories and find secondary vertices. It was the last detector to be installed in ATLAS in June 2007, has been fully connected and tested in-situ during spring and summer 2008, and is ready for the imminent LHC turn-on. The highlights of the past and future commissioning activities of themore » ATLAS pixel system are presented.« less

Forward-looking automotive radar sensor

NASA Astrophysics Data System (ADS)

Ganci, Paul; Potts, Steven; Okurowski, Frank

1995-12-01

For intelligent cruise control (ICC) and forward looking collision warning systems to be successful products they must provide robust performance in a complex roadway environment. Inconveniences caused by dropped tracks and nuisance alarms will not be tolerated by consumers, and would likely result in rejection of these new technologies in the marketplace. The authors report on a low-cost automotive millimeter wave (MMW) radar design which addresses shortcomings associated with previously reported ICC system implementations. The importance of the sensor's ability to identify and separately track all obstacles in the field of view is discussed. The applicability of the MMW's FM-CW sensor implementation to collision warning systems is also discussed.

Real-time tracking of objects for a KC-135 microgravity experiment

NASA Technical Reports Server (NTRS)

Littlefield, Mark L.

1994-01-01

The design of a visual tracking system for use on the Extra-Vehicular Activity Helper/Retriever (EVAHR) is discussed. EVAHR is an autonomous robot designed to perform numerous tasks in an orbital microgravity environment. Since the ability to grasp a freely translating and rotating object is vital to the robot's mission, the EVAHR must analyze range image generated by the primary sensor. This allows EVAHR to locate and focus its sensors so that an accurate set of object poses can be determined and a grasp strategy planned. To test the visual tracking system being developed, a mathematical simulation was used to model the space station environment and maintain dynamics on the EVAHR and any other free floating objects. A second phase of the investigation consists of a series of experiments carried out aboard a KC-135 aircraft flying a parabolic trajectory to simulate microgravity.

Accurate State Estimation and Tracking of a Non-Cooperative Target Vehicle

NASA Technical Reports Server (NTRS)

Thienel, Julie K.; Sanner, Robert M.

2006-01-01

Autonomous space rendezvous scenarios require knowledge of the target vehicle state in order to safely dock with the chaser vehicle. Ideally, the target vehicle state information is derived from telemetered data, or with the use of known tracking points on the target vehicle. However, if the target vehicle is non-cooperative and does not have the ability to maintain attitude control, or transmit attitude knowledge, the docking becomes more challenging. This work presents a nonlinear approach for estimating the body rates of a non-cooperative target vehicle, and coupling this estimation to a tracking control scheme. The approach is tested with the robotic servicing mission concept for the Hubble Space Telescope (HST). Such a mission would not only require estimates of the HST attitude and rates, but also precision control to achieve the desired rate and maintain the orientation to successfully dock with HST.

Non-RF wireless helmet-mounted display and two-way audio connectivity using covert free-space optical communications

NASA Astrophysics Data System (ADS)

Strauss, M.; Volfson, L.

2011-06-01

Providing the warfighter with Head or Helmet Mounted Displays (HMDs) while in tracked vehicles provides a means to visually maintain access to systems information while in a high vibration environment. The high vibration and unique environment of military tracked and turreted vehicles impact the ability to distinctly see certain information on an HMD, especially small font size or graphics and information that requires long fixation (staring), rather than a brief or peripheral glance. The military and commercial use of HMDs was compiled from market research, market trends, and user feedback. Lessons learned from previous military and commercial use of HMD products were derived to determine the feasibility of HMDs use in the high vibration and the unique environments of tracked vehicles. The results are summarized into factors that determine HMD features which must be specified for successful implementation.

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.

Application of inertial instruments for DSN antenna pointing and tracking

NASA Technical Reports Server (NTRS)

Eldred, D. B.; Nerheim, N. M.; Holmes, K. G.

1990-01-01

The feasibility of using inertial instruments to determine the pointing attitude of the NASA Deep Space Network antennas is examined. The objective is to obtain 1 mdeg pointing knowledge in both blind pointing and tracking modes to facilitate operation of the Deep Space Network 70 m antennas at 32 GHz. A measurement system employing accelerometers, an inclinometer, and optical gyroscopes is proposed. The initial pointing attitude is established by determining the direction of the local gravity vector using the accelerometers and the inclinometer, and the Earth's spin axis using the gyroscopes. Pointing during long-term tracking is maintained by integrating the gyroscope rates and augmenting these measurements with knowledge of the local gravity vector. A minimum-variance estimator is used to combine measurements to obtain the antenna pointing attitude. A key feature of the algorithm is its ability to recalibrate accelerometer parameters during operation. A survey of available inertial instrument technologies is also given.

Video guidance, landing, and imaging systems

NASA Technical Reports Server (NTRS)

Schappell, R. T.; Knickerbocker, R. L.; Tietz, J. C.; Grant, C.; Rice, R. B.; Moog, R. D.

1975-01-01

The adaptive potential of video guidance technology for earth orbital and interplanetary missions was explored. The application of video acquisition, pointing, tracking, and navigation technology was considered to three primary missions: planetary landing, earth resources satellite, and spacecraft rendezvous and docking. It was found that an imaging system can be mechanized to provide a spacecraft or satellite with a considerable amount of adaptability with respect to its environment. It also provides a level of autonomy essential to many future missions and enhances their data gathering ability. The feasibility of an autonomous video guidance system capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was successfully demonstrated in the laboratory. The techniques developed for acquisition, pointing, and tracking show promise for recognizing and tracking coastlines, rivers, and other constituents of interest. Routines were written and checked for rendezvous, docking, and station-keeping functions.

How far could energy transport within a single crystal

NASA Astrophysics Data System (ADS)

Zhang, Yifan; Che, Yanke; Zhao, Jincai; Steve, Granick

Efficient transport of excitation energy over long distance is a vital process in light-harvesting systems and molecular electronics. The energy transfer distance is largely restricted by the probability decay of the exciton when hopping within a single crystal. Here, we fabricated an organic single crystal within which the energy could transfer more than 100 μm, a distance only limited by its crystal size. Our system could be regarded as a ``Sprint relay game'' performing on different surface of tracks. Photoinduced ``athletes'' (excitons) triggered intermolecular ``domino'' reaction to propagate energy for a long distance. In addition, athletes with the same ability runs much farther on smooth ideal track (single crystal assembled from merely van der Waals interaction) than bumpy mud track (crystal assembled from combination of pi-stacking, hydrogen bond and van der Waals interactions). Our finding presents new physics on enhancing energy transfer length within a single crystal. Current Affiliation: Institute for Basic Science, South Korea.

Predictive Compensator Optimization for Head Tracking Lag in Virtual Environments

NASA Technical Reports Server (NTRS)

Adelstein, Barnard D.; Jung, Jae Y.; Ellis, Stephen R.

2001-01-01

We examined the perceptual impact of plant noise parameterization for Kalman Filter predictive compensation of time delays intrinsic to head tracked virtual environments (VEs). Subjects were tested in their ability to discriminate between the VE system's minimum latency and conditions in which artificially added latency was then predictively compensated back to the system minimum. Two head tracking predictors were parameterized off-line according to cost functions that minimized prediction errors in (1) rotation, and (2) rotation projected into translational displacement with emphasis on higher frequency human operator noise. These predictors were compared with a parameterization obtained from the VE literature for cost function (1). Results from 12 subjects showed that both parameterization type and amount of compensated latency affected discrimination. Analysis of the head motion used in the parameterizations and the subsequent discriminability results suggest that higher frequency predictor artifacts are contributory cues for discriminating the presence of predictive compensation.

Tracked robot controllers for climbing obstacles autonomously

NASA Astrophysics Data System (ADS)

Vincent, Isabelle

2009-05-01

Research in mobile robot navigation has demonstrated some success in navigating flat indoor environments while avoiding obstacles. However, the challenge of analyzing complex environments to climb obstacles autonomously has had very little success due to the complexity of the task. Unmanned ground vehicles currently exhibit simple autonomous behaviours compared to the human ability to move in the world. This paper presents the control algorithms designed for a tracked mobile robot to autonomously climb obstacles by varying its tracks configuration. Two control algorithms are proposed to solve the autonomous locomotion problem for climbing obstacles. First, a reactive controller evaluates the appropriate geometric configuration based on terrain and vehicle geometric considerations. Then, a reinforcement learning algorithm finds alternative solutions when the reactive controller gets stuck while climbing an obstacle. The methodology combines reactivity to learning. The controllers have been demonstrated in box and stair climbing simulations. The experiments illustrate the effectiveness of the proposed approach for crossing obstacles.

Comparison of standardbred trotters exercising on a treadmill and a race track with identical draught resistances.

PubMed

Gottlieb-Vedi, M; Lindholm, A

1997-05-17

The responses in heart rate, plasma lactate and rectal temperature of standardbred trotters to draught loaded interval exercise on a treadmill and a race track were studied. The horses were exercised with incrementally increasing trotting speeds for two-minute intervals with draught loads of 10, 20 and 30 kilopond (kp) in three different tests. Each trotting interval was followed by two-minute periods at a walk without a draught load. Measurements of heart rate and plasma lactate were made at the end of each interval and the rectal temperature was taken at the end of the exercise. The heart rate and plasma lactate levels were significantly lower on the treadmill than on the track in the tests with 10 kp, but no significant differences were found between the treadmill and track exercise tests with the heavier draught resistances. No differences were observed in rectal temperature between treadmill and track conditions. From these findings it was concluded that the workload was significantly greater on the race track compared to the treadmill when the draught resistance was low (10 kp). Although the workload increased on both the race track and the treadmill as draught resistance increased, at the heavier draught resistances track exercise was no longer more demanding than exercise on the treadmill.

Cortical Circuit for Binding Object Identity and Location During Multiple-Object Tracking

PubMed Central

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

Medical Internet of Things and Big Data in Healthcare.

PubMed

Dimitrov, Dimiter V

2016-07-01

A number of technologies can reduce overall costs for the prevention or management of chronic illnesses. These include devices that constantly monitor health indicators, devices that auto-administer therapies, or devices that track real-time health data when a patient self-administers a therapy. Because they have increased access to high-speed Internet and smartphones, many patients have started to use mobile applications (apps) to manage various health needs. These devices and mobile apps are now increasingly used and integrated with telemedicine and telehealth via the medical Internet of Things (mIoT). This paper reviews mIoT and big data in healthcare fields. mIoT is a critical piece of the digital transformation of healthcare, as it allows new business models to emerge and enables changes in work processes, productivity improvements, cost containment and enhanced customer experiences. Wearables and mobile apps today support fitness, health education, symptom tracking, and collaborative disease management and care coordination. All those platform analytics can raise the relevancy of data interpretations, reducing the amount of time that end users spend piecing together data outputs. Insights gained from big data analysis will drive the digital disruption of the healthcare world, business processes and real-time decision-making. A new category of "personalised preventative health coaches" (Digital Health Advisors) will emerge. These workers will possess the skills and the ability to interpret and understand health and well-being data. They will help their clients avoid chronic and diet-related illness, improve cognitive function, achieve improved mental health and achieve improved lifestyles overall. As the global population ages, such roles will become increasingly important.

Improving data retention in EEG research with children using child-centered eye tracking

PubMed Central

Maguire, Mandy J.; Magnon, Grant; Fitzhugh, Anna E.

2014-01-01

Background Event Related Potentials (ERPs) elicited by visual stimuli have increased our understanding of developmental disorders and adult cognitive abilities for decades; however, these studies are very difficult with populations who cannot sustain visual attention such as infants and young children. Current methods for studying such populations include requiring a button response, which may be impossible for some participants, and experimenter monitoring, which is subject to error, highly variable, and spatially imprecise. New Method We developed a child-centered methodology to integrate EEG data acquisition and eye-tracking technologies that uses “attention-getters” in which stimulus display is contingent upon the child’s gaze. The goal was to increase the number of trials retained. Additionally, we used the eye-tracker to categorize and analyze the EEG data based on gaze to specific areas of the visual display, compared to analyzing based on stimulus presentation. Results Compared with Existing Methods The number of trials retained was substantially improved using the child-centered methodology compared to a button-press response in 7–8 year olds. In contrast, analyzing the EEG based on eye gaze to specific points within the visual display as opposed to stimulus presentation provided too few trials for reliable interpretation. Conclusions By using the linked EEG-eye-tracker we significantly increased data retention. With this method, studies can be completed with fewer participants and a wider range of populations. However, caution should be used when epoching based on participants’ eye gaze because, in this case, this technique provided substantially fewer trials. PMID:25251555