Science.gov

Sample records for accessible pedestrian signals

  1. Crossroads: Modern Interactive Intersections and Accessible Pedestrian Signals

    ERIC Educational Resources Information Center

    Barlow, Janet M.; Franck, Lukas

    2005-01-01

    This article discusses the interactive nature of modern actuated intersections and the effect of that interface on pedestrians who are visually impaired. Information is provided about accessible pedestrian signals (APS), the role of blindness professionals in APS installation decisions, and techniques for crossing streets with APS.

  2. 76 FR 44663 - Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-26

    ...The Architectural and Transportation Barriers Compliance Board is proposing accessibility guidelines for the design, construction, and alteration of pedestrian facilities in the public right-of-way. The guidelines ensure that sidewalks, pedestrian street crossings, pedestrian signals, and other facilities for pedestrian circulation and use constructed or altered in the public right-of-way by......

  3. The Safety of Older Pedestrians at Signal-Controlled Crossings.

    ERIC Educational Resources Information Center

    Harrell, W. Andrew

    1996-01-01

    Observes the extent to which pedestrians checked for oncoming traffic before crossing signal-controlled intersections on busy city streets. Pedestrians over the age of 50 were the most cautious, especially under dangerous traffic conditions. Older pedestrians were least likely to use other pedestrians as "guides" to safety, instead checking for…

  4. Pedestrian signalization and the risk of pedestrian-motor vehicle collisions in Lima, Peru

    PubMed Central

    Quistberg, D. Alex; Koepsell, Thomas D.; Boyle, Linda Ng; Miranda, J. Jaime; Johnston, Brian D.; Ebel, Beth E.

    2014-01-01

    Safe walking environments are essential for protecting pedestrians and promoting physical activity. In Peru, pedestrians comprise of over three-quarters of road fatality victims. Pedestrian signalization plays an important role managing pedestrian and vehicle traffic and may help improve pedestrian safety. We examined the relationship between pedestrian-motor vehicle collisions and the presence of visible traffic signals, pedestrian signals, and signal timing to determine whether these countermeasures improved pedestrian safety. A matched case-control design was used where the units of study were crossing locations. We randomly sampled 97 control-matched collisions (weighted N=1134) at intersections occurring from October, 2010 to January, 2011 in Lima. Each case-control pair was matched on proximity, street classification, and number of lanes. Sites were visited between February, 2011 and September, 2011. Each analysis accounted for sampling weight and matching and was adjusted for vehicle and pedestrian traffic flow, crossing width, and mean vehicle speed. Collisions were more common where a phased pedestrian signal (green or red-lit signal) was present compared to no signalization (odds ratio [OR] 8.88, 95% Confidence Interval [CI] 1.32–59.6). A longer pedestrian-specific signal duration was associated with collision risk (OR 5.31, 95% CI 1.02–9.60 per 15-second interval). Collisions occurred more commonly in the presence of any signalization visible to pedestrians or pedestrian-specific signalization, though these associations were not statistically significant. Signalization efforts were not associated with lower risk for pedestrians; rather, they were associated with an increased risk of pedestrian-vehicle collisions. PMID:24821630

  5. Guidelines for Assessing the Need for Adaptive Devices for Visually Impaired Pedestrians at Signalized Intersections.

    ERIC Educational Resources Information Center

    Gallagher, Brian R.; de Oca, Patricia Montes

    1998-01-01

    Presents guidelines for orientation and mobility instructors and traffic engineers to assess the need for adaptive devices to make crosswalks at signalized intersections accessible to pedestrians with visual impairments. The discussions of audible and tactile pedestrian devices, along with case examples, distinguish when each device should be…

  6. Modern Roundabouts: Access by Pedestrians Who Are Blind

    ERIC Educational Resources Information Center

    Long, Richard G.; Guth, David A.; Ashmead, Daniel H.; Emerson, Robert Wall; Ponchillia, Paul E.

    2005-01-01

    This article describes the key differences between roundabouts and traditional intersections that have traffic signals or stop signs and discusses how these differences may affect the mobility of pedestrians who are visually impaired. It also provides a brief summary of the authors' research on this topic and suggests strategies for addressing the…

  7. Analyzing pedestrian crash injury severity at signalized and non-signalized locations.

    PubMed

    Haleem, Kirolos; Alluri, Priyanka; Gan, Albert

    2015-08-01

    This study identifies and compares the significant factors affecting pedestrian crash injury severity at signalized and unsignalized intersections. The factors explored include geometric predictors (e.g., presence and type of crosswalk and presence of pedestrian refuge area), traffic predictors (e.g., annual average daily traffic (AADT), speed limit, and percentage of trucks), road user variables (e.g., pedestrian age and pedestrian maneuver before crash), environmental predictors (e.g., weather and lighting conditions), and vehicle-related predictors (e.g., vehicle type). The analysis was conducted using the mixed logit model, which allows the parameter estimates to randomly vary across the observations. The study used three years of pedestrian crash data from Florida. Police reports were reviewed in detail to have a better understanding of how each pedestrian crash occurred. Additionally, information that is unavailable in the crash records, such as at-fault road user and pedestrian maneuver, was collected. At signalized intersections, higher AADT, speed limit, and percentage of trucks; very old pedestrians; at-fault pedestrians; rainy weather; and dark lighting condition were associated with higher pedestrian severity risk. For example, a one-percent higher truck percentage increases the probability of severe injuries by 1.37%. A one-mile-per-hour higher speed limit increases the probability of severe injuries by 1.22%. At unsignalized intersections, pedestrian walking along roadway, middle and very old pedestrians, at-fault pedestrians, vans, dark lighting condition, and higher speed limit were associated with higher pedestrian severity risk. On the other hand, standard crosswalks were associated with 1.36% reduction in pedestrian severe injuries. Several countermeasures to reduce pedestrian injury severity are recommended. PMID:25935426

  8. Directional guidance from audible pedestrian signals for street crossing.

    PubMed

    Wall, Robert S; Ashmead, Daniel H; Bentzen, Billie Louise; Barlow, Janet

    2004-10-10

    Typical audible pedestrian signals indicate when the pedestrian walk interval is in effect but provide little, or even misleading information for directional alignment. In three experiments, blind and blindfolded sighted adults crossed a simulated crossing with recorded traffic noise to approximate street sounds. This was done to investigate how characteristics of signal presentation affected usefulness of the auditory signal for guiding crossing behaviour. Crossing was more accurate when signals came only from the far end of the crossing rather than the typical practice of presenting signals simultaneously from both ends. Alternating the signal between ends of the crossing was not helpful. Also, the customary practice of signalling two parallel crossings at the same time drew participants somewhat toward the opposite crossing. Providing a locator tone at the end of the crossing during the pedestrian clearance interval improved crossing accuracy. These findings provide a basis for designing audible pedestrian signals to enhance directional guidance. The principal findings were the same for blind and sighted participants and applied across a range of specific signals (e.g. chirps, clicks, voices). PMID:15370850

  9. Developing crash modification functions for pedestrian signal improvement.

    PubMed

    Sacchi, Emanuele; Sayed, Tarek; Osama, Ahmed

    2015-10-01

    Pedestrian signals are viable traffic control devices that help pedestrians to cross safely at intersections. Although the literature is extensive when dealing with pedestrian signals design and operations, few studies have focused on the potential safety benefits of installing pedestrian signals at intersections. Most of these studies employed simple before-after (BA) safety evaluation techniques which suffer from methodological and statistical issues. Recent advances in safety evaluation research advocate the use of crash modification functions (CMFunctions) to represent the safety effectiveness of treatments. Unlike crash modification factors (CMFs) that are represented as single values, CMFunctions account for variable treatment location characteristics (heterogeneity). Therefore, the main objective of this study was to quantify the safety impact of installing pedestrian signals at signalized intersections by developing CMFunctions within an observational BA study. The use of observational BA framework to develop the CMFunctions avoids the cross-sectional approach where the functions are derived based on a single time period and no actual treatment intervention. Treatment sites heterogeneity was incorporated into CMFunctions using fixed-effects and random-effects regression models. In addition to heterogeneity, the paper also advocates the use of CMFunctions with a time variable to acknowledge that the safety treatment (intervention) effects do not occur instantaneously but are spread over future time. This is achieved using non-linear intervention (Koyck) models, developed within a hierarchical full Bayes context. The results demonstrated the importance of considering treatment sites heterogeneity (i.e., different circulating volumes and area type among treated locations) and time trends when developing CMFunctions for pedestrian signal improvement. PMID:26196466

  10. Perception of Pedestrian Signals by Pedestrians with Varying Levels of Vision

    PubMed Central

    Atkins, Katherine N.; Bentzen, Billie Louise; Barlow, Janet M.

    2013-01-01

    This study evaluates the usability of pedestrian signals by persons with varying visual acuities under different conditions of symbol size, crossing length and type of background behind the pedestrian signal. While viewing photographs presented on a computer monitor under unimpaired viewing conditions (approx. 20/20 visual acuity) and under simulated visual impairment (approx. acuities of 20/100 and 20/300), participants attempted to determine the pedestrian phase (Walk or Don’t Walk) and to report the number presented by the countdown timer display. Performance on the phase discrimination task by those with simulated 20/300 acuity and with 9 and 12 in. high symbols often resulted in performance which was little better than chance despite a highly controlled environment (i.e., no moving vehicles or environmental distractions) and signals which were subjectively in excellent working condition and of high visibility (i.e., good luminance/contrast, no glare). Reading the countdown display was essentially impossible. Participants with simulated 20/100 acuity were rather successful with regards to phase identification – averaging better than 87% correct under all stimulus conditions – but room for improvement exists as compared to performance in the 20/20 condition. Reading the countdown display was difficult for participants with simulated 20/100 acuity – averaging between 6.5% and 58.5% correct under the various stimulus conditions. The effect of different backgrounds on the usability of the signals, as well as the implications of the findings with regards to signal size and crossing length on the current signals standards, are discussed. PMID:24391305

  11. Improving pedestrian access to transit. An advocacy handbook

    SciTech Connect

    1998-09-19

    This report was written as a teaching tool for ordinary citizens, and for transportation and urban planners working with citizen groups, who advocate for public transit and walkable neighborhoods. It illustrates key steps that activists can take to ensure that mass transit supports community needs and creates livable communities through improved pedestrian access. The authors present their personal experience in case studies that detail advocacy techniques and strategies. They also identify some failures and setbacks. The report discussed several public transit modes (e.g., bus, light rail, and subway) used in different kinds of communities (low-income urban neighborhoods, upper- and middle-income inner suburb). The authors are from WalkBoston, a nonprofit organization that promotes walking and transit.

  12. An accelerated failure time model for investigating pedestrian crossing behavior and waiting times at signalized intersections.

    PubMed

    Yang, Xiaobao; Abdel-Aty, Mohamed; Huan, Mei; Peng, Yichuan; Gao, Ziyou

    2015-09-01

    The waiting process is crucial to pedestrians in the street-crossing behavior. Once pedestrians terminate their waiting behavior during the red light period, they would cross against the red light and put themselves in danger. A joint hazard-based duration model is developed to investigate the effect of various covariates on pedestrian crossing behavior and to estimate pedestrian waiting times at signalized intersections. A total of 1181 pedestrians approaching the intersections during red light periods were observed in Beijing, China. Pedestrian crossing behaviors are classified into immediate crossing behavior and waiting behavior. The probability and effect of various covariates for pedestrians' immediate crossing behavior are identified by a logit model. Four accelerated failure time duration models based on the exponential, Weibull, lognormal and log-logistic distributions are proposed to examine the significant risk factors affecting duration times for pedestrians' waiting behavior. A joint duration model is developed to estimate pedestrian waiting times. Moreover, unobserved heterogeneity is considered in the proposed model. The results indicate that the Weibull AFT model with shared frailty is appropriate for modelling pedestrian waiting durations. Failure to account for heterogeneity would significantly underestimate the effects of covariates on waiting duration times. The proposed model provides a better understanding of pedestrian crossing behavior and more accurate estimation of pedestrian waiting times. It may be applicable in traffic system analysis in developing countries with high flow of mixed traffic. PMID:26072184

  13. Working Concept of Accessibility: Performance Measures for Usability of Crosswalks by Pedestrians with Vision Impairments.

    PubMed

    Schroeder, Bastian J; Rouphail, Nagui M; Hughes, Ronald G

    2010-01-22

    This research presents an analysis framework and associated performance measures for quantifying the accessibility of pedestrian crossings at modern roundabouts for pedestrians who are blind. The measures, developed under two ongoing national research projects, NCHRP Project 3-78A and a bioengineering research grant from the National Institutes of Health-National Eye Institute, attempt to isolate the components of the crossing task for a blind pedestrian into computable and replicable quantities that allow the comparison of accessibility across individuals or sites. The framework differentiates between crossing opportunities in the form of yields and crossable gaps and the utilization of these opportunities by the pedestrian. It further accounts for the amount of delay and risk involved in the crossing. The analysis framework and measures are demonstrated for two single-lane roundabouts in North Carolina evaluated under the aforementioned research projects. The application shows that the accessibility of a pedestrian crossing to a blind pedestrian is characterized by a combination of different measures and further depends on crossing geometry, traffic volume, driver behavior, and the travel skills and risk-taking behavior of the individual. With successful demonstration at roundabout crosswalks, the analysis framework is hypothesized to have broader application to unsignalized pedestrian crossings, including midblock locations. PMID:20664802

  14. The influence of pedestrian countdown signals on children's crossing behavior at school intersections.

    PubMed

    Fu, Lianning; Zou, Nan

    2016-09-01

    Previous studies have shown that pedestrian countdown signals had different influences on pedestrian crossing behavior. The purpose of this study was to examine the effects of the installation of countdown signals at school intersections on children's crossing behavior. A comparison analysis was carried out on the basis of observations at two different school intersections with or without pedestrian countdown signals in the city of Jinan, China. Four types of children's crossing behavior and child pedestrian-vehicle conflicts were analyzed in detail. The analysis results showed that using pedestrian countdown timers during the Red Man phase led to more children's violation and running behavior. Theses violators created more conflicts with vehicles. However, pedestrian countdown signals were effective at helping child pedestrian to complete crossing before the red light onset, avoid getting caught in the middle of crosswalk. No significant difference was found in children who started crossing during Flashing Green Man phase between the two types of pedestrian signals. Moreover, analysis results indicated that children who crossed the road alone had more violation and adventure crossing behavior than those had companions. Boys were found more likely to run crossing than girls, but there was no significant gender difference in other crossing behavior. Finally, it's recommended to remove countdown at the end of the Red Man phase to improve children's crossing behavior and reduce the conflicts with vehicles. Meanwhile other measures are proposed to improve children safety at school intersections. PMID:27261555

  15. 10 CFR 431.222 - Definitions concerning traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operation; and (2) Communicates movement messages to drivers through red, amber, and green colors. Test... signal has been operated for 60 minutes. Pedestrian module means a light signal used to convey...

  16. 10 CFR 431.222 - Definitions concerning traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... operation; and (2) Communicates movement messages to drivers through red, amber, and green colors. Test... signal has been operated for 60 minutes. Pedestrian module means a light signal used to convey...

  17. 76 FR 45481 - Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-29

    ... site at: http://www.access-board.gov/prowac/nprm.htm . Correction In the proposed rule FR Doc. 2011... TRANSPORTATION BARRIERS COMPLIANCE BOARD 36 CFR Part 1190 RIN 3014-AA26 Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way AGENCY: Architectural and Transportation Barriers Compliance...

  18. 10 CFR 431.222 - Definitions concerning traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... convey movement information to pedestrians. Traffic signal module means a standard 8-inch (200 mm) or 12... parts necessary for operation; and (2) Communicates movement messages to drivers through red, amber, and green colors. Test Procedures...

  19. 10 CFR 431.222 - Definitions concerning traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... convey movement information to pedestrians. Traffic signal module means a standard 8-inch (200 mm) or 12... parts necessary for operation; and (2) Communicates movement messages to drivers through red, amber, and green colors. Test Procedures...

  20. 10 CFR 431.222 - Definitions concerning traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... convey movement information to pedestrians. Traffic signal module means a standard 8-inch (200 mm) or 12... parts necessary for operation; and (2) Communicates movement messages to drivers through red, amber, and green colors. Test Procedures...

  1. U-Access: a web-based system for routing pedestrians of differing abilities

    NASA Astrophysics Data System (ADS)

    Sobek, Adam D.; Miller, Harvey J.

    2006-09-01

    For most people, traveling through urban and built environments is straightforward. However, for people with physical disabilities, even a short trip can be difficult and perhaps impossible. This paper provides the design and implementation of a web-based system for the routing and prescriptive analysis of pedestrians with different physical abilities within built environments. U-Access, as a routing tool, provides pedestrians with the shortest feasible route with respect to one of three differing ability levels, namely, peripatetic (unaided mobility), aided mobility (mobility with the help of a cane, walker or crutches) and wheelchair users. U-Access is also an analytical tool that can help identify obstacles in built environments that create routing discrepancies among pedestrians with different physical abilities. This paper discusses the system design, including database, algorithm and interface specifications, and technologies for efficiently delivering results through the World Wide Web (WWW). This paper also provides an illustrative example of a routing problem and an analytical evaluation of the existing infrastructure which identifies the obstacles that pose the greatest discrepancies between physical ability levels. U-Access was evaluated by wheelchair users and route experts from the Center for Disability Services at The University of Utah, USA.

  2. An Indoor Space Partition Method and its Fingerprint Positioning Optimization Considering Pedestrian Accessibility

    NASA Astrophysics Data System (ADS)

    Xu, Yue; Shi, Yong; Zheng, Xingyu; Long, Yi

    2016-06-01

    Fingerprint positioning method is generally the first choice in indoor navigation system due to its high accuracy and low cost. The accuracy depends on partition density to the indoor space. The accuracy will be higher with higher grid resolution. But the high grid resolution leads to significantly increasing work of the fingerprint data collection, processing and maintenance. This also might decrease the performance, portability and robustness of the navigation system. Meanwhile, traditional fingerprint positioning method use equational grid to partition the indoor space. While used for pedestrian navigation, sometimes a person can be located at the area where he or she cannot access. This paper studied these two issues, proposed a new indoor space partition method considering pedestrian accessibility, which can increase the accuracy of pedestrian position, and decrease the volume of the fingerprint data. Based on this proposed partition method, an optimized algorithm for fingerprint position was also designed. A across linker structure was used for fingerprint point index and matching. Experiment based on the proposed method and algorithm showed that the workload of fingerprint collection and maintenance were effectively decreased, and poisoning efficiency and accuracy was effectively increased

  3. 10 CFR 429.49 - Traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Traffic signal modules and pedestrian modules. 429.49 Section 429.49 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT... nominal wattage or other measure of energy consumption of a basic model for which consumers would...

  4. 10 CFR 429.49 - Traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Traffic signal modules and pedestrian modules. 429.49 Section 429.49 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT... nominal wattage or other measure of energy consumption of a basic model for which consumers would...

  5. 10 CFR 429.49 - Traffic signal modules and pedestrian modules.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Traffic signal modules and pedestrian modules. 429.49 Section 429.49 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT... nominal wattage or other measure of energy consumption of a basic model for which consumers would...

  6. Blind Pedestrians and the Changing Technology and Geometry of Signalized Intersections: Safety, Orientation, and Independence

    ERIC Educational Resources Information Center

    Barlow, Janet M.; Bentzen, Billie Louise; Bond, Tamara

    2005-01-01

    This study documented that blind pedestrians have considerable difficulty locating crosswalks, aligning to cross, determining the onset of the walk interval, maintaining a straight crossing path, and completing crossings before the onset of perpendicular traffic at complex signalized intersections. Revised techniques and strategies are suggested…

  7. 76 FR 75844 - Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way; Reopening of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-05

    ... (76 FR 44664). In that notice, the Access Board proposed guidelines for accessible public rights-of... TRANSPORTATION BARRIERS COMPLIANCE BOARD 36 CFR Part 1190 RIN 3014-AA26 Accessibility Guidelines for Pedestrian... Barriers Compliance Board. ACTION: Notice of proposed rulemaking; reopening of comment period. SUMMARY:...

  8. Development and Implementation of a Conflict-based Assessment of Pedestrian Safety (CAPS) to Evaluate Accessibility of Complex Intersections

    PubMed Central

    Salamati, Katayoun; Rouphail, Nagui M.; Cunningham, Christopher; Long, Richard; Barlow, Janet

    2011-01-01

    This paper develops and implements the Conflict-based Assessment of Pedestrian Safety (CAPS) methodology for evaluating pedestrian accessibility at complex intersections. In past years, a significant research has been done on pedestrian access to modern roundabouts and other complex intersection forms, including a significant focus on the accessibility for pedestrians who are blind. A majority of these studies have relied on actual street crossings by study participants under supervision of trained Orientation and Mobility (O&M) Specialist. These crossing studies were used to evaluate risk from a measurement of intervention events, where the O&M specialist had to physically stop the participant from crossing. While providing arguably the most accurate data for the crossing risk at a particular intersection, actual street crossings can be dangerous to the study participants, and are further very time consuming and expensive to conduct. The CAPS method presented in this paper emphasizes the use of conflict-based safety factors to quantify risk. The CAPS method relates pedestrian crossing decisions to advanced measurements of vehicle dynamics to estimate lane-by-lane conflicts. CAPS identifies the grade of conflict based on a score generated on a five-criterion rating scale. Each of these criteria or factors has different severity levels, and when combined, provides an overall risk rating of the crossing decision. The CAPS framework was applied to a study of blind pedestrian crossings at a multi-lane roundabout. The resulting risk scores were calibrated from actual O&M interventions observed during the study to give confidence in the CAPS performance. The calibrated CAPS framework correctly matched all (high risk) O&M intervention events, and further identifies other (lower risk) pedestrian-vehicle conflicts. The resulting method has the potential to allow for a faster and most importantly safer evaluation of complex intersections for pedestrian access. Since all

  9. 78 FR 10110 - Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way; Shared Use Paths

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... on July 26, 2011. See 76 FR 44664 (July 26, 2011). A copy of the proposed accessibility guidelines... for trails and other outdoor developed areas in 2007. See 72 FR 34074 (June 20, 2007). A trail would... for sidewalks and other pedestrian facilities in the public right-of-way in 2002 and 2005. See 67...

  10. Red light violations by adult pedestrians and other safety-related behaviors at signalized crosswalks.

    PubMed

    Dommes, A; Granié, M-A; Cloutier, M-S; Coquelet, C; Huguenin-Richard, F

    2015-07-01

    To study human factors linked to red light violations, and more generally to safety-related behaviors at signalized crosswalks, the present study combines the collection of observational data with questionnaires answered by 422 French adult pedestrians. Thirteen behavioral indicators were extracted (12 before and while crossing, and red light violation), and the roles of several demographical, contextual and mobility-associated variables were examined. The results of the stepwise logistic regression analyses carried out on each of the 12 behavioral indicators observed before and while crossing revealed that gender had no major impact, but age did, with more cautious behaviors as pedestrians were older. The three contextual variables (group size, parked vehicles, and traffic density), as four mobility-associated variables (driving and walking experiences, self-reported crossing difficulties and falls in the street) were also found to be important factors in safety-related crossing behaviors. A wider logistic regression analysis, made specifically on red light violations with all behavioral indicators observed before and while crossings and the several demographical, contextual and mobility-associated variables put together, showed that red light violations were mostly affected by current situational factors (group size, parked vehicles) and particularly associated with some behavioral patterns (looking toward the traffic, the ground, the light, running and crossing diagonally). The overall results encourage the development of safer pedestrian infrastructures and engineering countermeasures. PMID:25884542

  11. Exploring motorcycle red-light violation in response to pedestrian green signal countdown device.

    PubMed

    Chen, Ping-Ling; Pai, Chih-Wei; Jou, Rong-Chang; Saleh, Wafaa; Kuo, Ming-Shin

    2015-02-01

    Literature has suggested that angle/rear-end collisions would arise from the reality that motorists and motorcyclists tended to accelerate aggressively in response to the remaining seconds of green signal countdown device (GSCD). One safety concern, while GSCD has gradually been removed for safety in Taiwan, is pedestrian green signal countdown device (PGSCD) that is used by approaching motorists and motorcyclists that may adopt the information to travel aggressively - an unintended consequence that is detrimental to safety. Research has reported that there appeared no negative effect of PGSCD on motorist behaviours but the effect on motorcyclists' behaviours has been rarely investigated. Using video/speed cameras, the current research investigates motorcyclists' RLV (red-light violation) behaviours. The descriptive analyses indicate that the percentage of RLV at PGSCD intersection is higher than that at typical intersection, and the violating motorcycles appear to have higher travelling speeds at PGSCD intersection. Several interaction terms were examined with the binary logit framework, and the results reveal that several factors are associated with RLV, notably male/young riders, moped/large motorcycle users, higher approaching speeds of motorcycles, those with tropical helmets, and lower traffic volume. Similar determinants of early-start behaviours (for those waiting at reds and could view the PGSCDs for the crossing pedestrians at the same time) were identified. Implications of the research findings, the concluding remarks, and recommendations for future research are finally provided. PMID:25460099

  12. The impact of pedestrian countdown signals on pedestrian–motor vehicle collisions: a quasi-experimental study

    PubMed Central

    Camden, Andi; Buliung, Ron; Rothman, Linda; Macarthur, Colin

    2011-01-01

    Objective To determine whether pedestrian countdown signals (PCS) reduce pedestrian–motor vehicle collisions in the city of Toronto, Canada. Methods A quasi-experimental study design was used to evaluate the effect of PCS on the number of pedestrian–motor vehicle collisions in the city of Toronto, from January 2000 to December 2009. Each intersection acted as its own control. We compared the number of pedestrian–motor vehicle collisions per intersection-month before and after the intervention. Stratified models were used to evaluate effect modification by pedestrian age, injury severity and location (urban vs inner suburbs). Poisson regression analysis with repeated measures (generalised estimating equations) was used to estimate the RR and 95% CI. Results The analysis included 9262 pedestrian–motor vehicle collisions at 1965 intersections. The RR of collisions after PCS installation was 1.014 (95% CI 0.958 to 1.073), indicating no statistically significant effect of PCS on collisions. There was no evidence to suggest effect modification between PCS and collisions by age, injury severity or location. Conclusion The installation of PCS at 1965 signalised intersections in Toronto did not reduce the number of pedestrian–motor vehicle collisions at these intersections. PMID:22157206

  13. Effects of Pedestrian Prompts on Motorist Yielding at Crosswalks

    ERIC Educational Resources Information Center

    Crowley-Koch, Brian J.; Van Houten, Ron; Lim, Eunyoung

    2011-01-01

    Pedestrian safety is a serious concern at busy intersections and pedestrian campuses across the nation. Although crosswalks and signs inform pedestrians where to cross, there is no standard protocol for pedestrians to signal drivers that they wish to use the crosswalks, except to stand in or at the crosswalk. We examined the effects of two…

  14. Precautionary street crossing by elderly pedestrians.

    PubMed

    Harrell, W A

    1991-01-01

    Street crossing behavior of pedestrians was observed under varying roadway conditions and traffic volumes. The extent to which pedestrians checked for oncoming traffic before crossing signal controlled intersections on a dangerous downtown street was observed. Contrary to the stereotypical portrayal of older pedestrians as being less cognizant of the traffic environment, pedestrians in this study over the age of fifty years were the most cautious. Older pedestrians were also more cautious under the most potentially hazardous crossing conditions: when roadways were snow- or ice-covered and when traffic volumes were low or moderate, allowing vehicles to move rapidly through intersections. PMID:2022437

  15. Modeling pedestrian's conformity violation behavior: a complex network based approach.

    PubMed

    Zhou, Zhuping; Hu, Qizhou; Wang, Wei

    2014-01-01

    Pedestrian injuries and fatalities present a problem all over the world. Pedestrian conformity violation behaviors, which lead to many pedestrian crashes, are common phenomena at the signalized intersections in China. The concepts and metrics of complex networks are applied to analyze the structural characteristics and evolution rules of pedestrian network about the conformity violation crossings. First, a network of pedestrians crossing the street is established, and the network's degree distributions are analyzed. Then, by using the basic idea of SI model, a spreading model of pedestrian illegal crossing behavior is proposed. Finally, through simulation analysis, pedestrian's illegal crossing behavior trends are obtained in different network structures and different spreading rates. Some conclusions are drawn: as the waiting time increases, more pedestrians will join in the violation crossing once a pedestrian crosses on red firstly. And pedestrian's conformity violation behavior will increase as the spreading rate increases. PMID:25530755

  16. Modeling Pedestrian's Conformity Violation Behavior: A Complex Network Based Approach

    PubMed Central

    Zhou, Zhuping; Hu, Qizhou; Wang, Wei

    2014-01-01

    Pedestrian injuries and fatalities present a problem all over the world. Pedestrian conformity violation behaviors, which lead to many pedestrian crashes, are common phenomena at the signalized intersections in China. The concepts and metrics of complex networks are applied to analyze the structural characteristics and evolution rules of pedestrian network about the conformity violation crossings. First, a network of pedestrians crossing the street is established, and the network's degree distributions are analyzed. Then, by using the basic idea of SI model, a spreading model of pedestrian illegal crossing behavior is proposed. Finally, through simulation analysis, pedestrian's illegal crossing behavior trends are obtained in different network structures and different spreading rates. Some conclusions are drawn: as the waiting time increases, more pedestrians will join in the violation crossing once a pedestrian crosses on red firstly. And pedestrian's conformity violation behavior will increase as the spreading rate increases. PMID:25530755

  17. Pedestrian Friendly Outdoor Lighting

    SciTech Connect

    Miller, N. J.; Koltai, R. N.; McGowan, T. K.

    2013-12-01

    The GATEWAY program followed two pedestrian-scale lighting projects that required multiple mockups – one at Stanford University in California and the other at Chautauqua Institution in upstate New York. The report provides insight into pedestrian lighting criteria, how they differ from street and area lighting criteria, and how solid-state lighting can be better applied in pedestrian applications.

  18. Impact of grade separator on pedestrian risk taking behavior.

    PubMed

    Khatoon, Mariya; Tiwari, Geetam; Chatterjee, Niladri

    2013-01-01

    Pedestrians on Delhi roads are often exposed to high risks. This is because the basic needs of pedestrians are not recognized as a part of the urban transport infrastructure improvement projects in Delhi. Rather, an ever increasing number of cars and motorized two-wheelers encourage the construction of large numbers of flyovers/grade separators to facilitate signal free movement for motorized vehicles, exposing pedestrians to greater risk. This paper describes the statistical analysis of pedestrian risk taking behavior while crossing the road, before and after the construction of a grade separator at an intersection of Delhi. A significant number of pedestrians are willing to take risks in both before and after situations. The results indicate that absence of signals make pedestrians behave independently, leading to increased variability in their risk taking behavior. Variability in the speeds of all categories of vehicles has increased after the construction of grade separators. After the construction of the grade separator, the waiting time of pedestrians at the starting point of crossing has increased and the correlation between waiting times and gaps accepted by pedestrians show that after certain time of waiting, pedestrians become impatient and accepts smaller gap size to cross the road. A Logistic regression model is fitted by assuming that the probability of road crossing by pedestrians depends on the gap size (in s) between pedestrian and conflicting vehicles, sex, age, type of pedestrians (single or in a group) and type of conflicting vehicles. The results of Logistic regression explained that before the construction of the grade separator the probability of road crossing by the pedestrian depends on only the gap size parameter; however after the construction of the grade separator, other parameters become significant in determining pedestrian risk taking behavior. PMID:22857788

  19. Multiple pedestrian detection using IR LED stereo camera

    NASA Astrophysics Data System (ADS)

    Ling, Bo; Zeifman, Michael I.; Gibson, David R. P.

    2007-09-01

    As part of the U.S. Department of Transportations Intelligent Vehicle Initiative (IVI) program, the Federal Highway Administration (FHWA) is conducting R&D in vehicle safety and driver information systems. There is an increasing number of applications where pedestrian monitoring is of high importance. Visionbased pedestrian detection in outdoor scenes is still an open challenge. People dress in very different colors that sometimes blend with the background, wear hats or carry bags, and stand, walk and change directions unpredictably. The background is various, containing buildings, moving or parked cars, bicycles, street signs, signals, etc. Furthermore, existing pedestrian detection systems perform only during daytime, making it impossible to detect pedestrians at night. Under FHWA funding, we are developing a multi-pedestrian detection system using IR LED stereo camera. This system, without using any templates, detects the pedestrians through statistical pattern recognition utilizing 3D features extracted from the disparity map. A new IR LED stereo camera is being developed, which can help detect pedestrians during daytime and night time. Using the image differencing and denoising, we have also developed new methods to estimate the disparity map of pedestrians in near real time. Our system will have a hardware interface with the traffic controller through wireless communication. Once pedestrians are detected, traffic signals at the street intersections will change phases to alert the drivers of approaching vehicles. The initial test results using images collected at a street intersection show that our system can detect pedestrians in near real time.

  20. Identification of radionuclides for the spectroscopic radiation portal monitor for pedestrian screening under a low signal-to-noise ratio condition

    NASA Astrophysics Data System (ADS)

    Min, Eungi; Ko, Mincheol; Lee, Hakjae; Kim, Yongkwon; Joung, Jinhun; Joo, Sung-Kwan; Lee, Kisung

    2014-09-01

    The spectroscopic radiation portal monitor (SPM) is widely used for homeland security. Many research groups are studying the radionuclide identification method which is one of the most important factors in the performance of the SPM using the large size of a thallium activated sodium iodide (NaI(Tl) detector. In this study, we developed the radionuclide identification method for the SPM for pedestrian screening using a single NaI(Tl) detector that is small in size (2 in.), which is much smaller than those in the existing studies under the low signal-to-noise-ratio (SNR) condition. From the anomalous radionuclide spectrum, the noise component was effectively reduced by the wavelet decomposition and the proposed background subtraction method, and the signal component was enhanced by the principal component analysis. Finally, peak locations which have been determined by the peak search algorithm with a valley check method were compared with a pre-calibrated and constructed radionuclide database. To verify the radiation identification performance of the proposed method, experiments with various kinds of sources (137Cs, 133Ba, 22Na, and 57Co) and different SNR values (from distances of 10-150 cm and for scan times of 1-5 s) were performed. Although the high-SNR condition was explored as well, most experiments were conducted under the low-SNR condition to verify the robustness and reproducibility of the proposed algorithm. The results showed that over 98.3% of the single radionuclide detection rate was achieved regardless of which radionuclides were used, up to 50 cm under the worst SNR condition (1 s of scan time) and up to 90 cm under the best SNR condition (5 s of scan time). Furthermore we achieved accurate identification of multiple radionuclides at 40 cm with only 1 s of scan time. The results show that the proposed algorithm is competitive with the commercial method and our radionuclide identification method can be successfully applied to the SPM for pedestrian

  1. Gap acceptance of violators at signalised pedestrian crossings.

    PubMed

    Koh, P P; Wong, Y D

    2014-01-01

    Gap acceptance of violating pedestrians was studied at seven stretches of signalised pedestrian crossings in Singapore. The provision of the traffic light signals provide a 'safer' crossing option to these pedestrians, as compared to uncontrolled crossings and mid-block arterial roads. However, there are still people choosing to cross at the riskier period (Red Man phase). The paper discusses about the size of traffic gaps rejected and accepted by pedestrians and the behaviour of riskier pedestrians (those adapting partial gap). The likelihood of pedestrians accepting gaps between vehicular traffic as a combination of different influencing independent variables such as traffic, environmental and personal factors was studied and modelled using logistic regression. PMID:24172084

  2. 31 CFR 700.10 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Vehicular and pedestrian traffic. 700... pedestrian traffic. (a) Drivers of all vehicles on the property shall drive in a careful and safe manner at all times and shall comply with the signals and directions of security officers and all posted...

  3. 31 CFR 700.10 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Vehicular and pedestrian traffic. 700... pedestrian traffic. (a) Drivers of all vehicles on the property shall drive in a careful and safe manner at all times and shall comply with the signals and directions of security officers and all posted...

  4. 4 CFR 25.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 4 Accounts 1 2012-01-01 2012-01-01 false Vehicular and pedestrian traffic. 25.13 Section 25.13... OFFICE BUILDING AND ON ITS GROUNDS § 25.13 Vehicular and pedestrian traffic. (a) Drivers of all vehicles... at all times and shall comply with all posted traffic signs and with the signals and directions...

  5. 4 CFR 25.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 4 Accounts 1 2014-01-01 2013-01-01 true Vehicular and pedestrian traffic. 25.13 Section 25.13... OFFICE BUILDING AND ON ITS GROUNDS § 25.13 Vehicular and pedestrian traffic. (a) Drivers of all vehicles... at all times and shall comply with all posted traffic signs and with the signals and directions...

  6. 4 CFR 25.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 4 Accounts 1 2013-01-01 2013-01-01 false Vehicular and pedestrian traffic. 25.13 Section 25.13... OFFICE BUILDING AND ON ITS GROUNDS § 25.13 Vehicular and pedestrian traffic. (a) Drivers of all vehicles... at all times and shall comply with all posted traffic signs and with the signals and directions...

  7. 4 CFR 25.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 4 Accounts 1 2011-01-01 2011-01-01 false Vehicular and pedestrian traffic. 25.13 Section 25.13... OFFICE BUILDING AND ON ITS GROUNDS § 25.13 Vehicular and pedestrian traffic. (a) Drivers of all vehicles... at all times and shall comply with all posted traffic signs and with the signals and directions...

  8. 31 CFR 700.10 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Vehicular and pedestrian traffic. 700... pedestrian traffic. (a) Drivers of all vehicles on the property shall drive in a careful and safe manner at all times and shall comply with the signals and directions of security officers and all posted...

  9. 31 CFR 700.10 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Vehicular and pedestrian traffic. 700... pedestrian traffic. (a) Drivers of all vehicles on the property shall drive in a careful and safe manner at all times and shall comply with the signals and directions of security officers and all posted...

  10. 31 CFR 700.10 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Vehicular and pedestrian traffic. 700... pedestrian traffic. (a) Drivers of all vehicles on the property shall drive in a careful and safe manner at all times and shall comply with the signals and directions of security officers and all posted...

  11. Pedestrians. Traffic Safety Facts, 2000.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This document provides statistical information on U.S. traffic accidents involving pedestrians. Data tables include: (1) trends in pedestrian and total traffic fatalities, 1990-2000; (2) pedestrians killed and injured, by age group, 2000; (3) non-occupant traffic fatalities, 1990-2000; (4) pedestrian fatalities, by time of day and day of week,…

  12. Traffic Safety Facts, 2001: Pedestrians.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This document provides statistical information on U.S. traffic accidents involving pedestrians. Data tables include: (1) trends in pedestrian and total traffic fatalities, 1991-2001; (2) pedestrians killed and injured, by age group, 2001; (3) non-occupant traffic fatalities, 1991-2001; (4) pedestrian fatalities, by time of day and day of week,…

  13. Pedestrian Friendly Outdoor Lighting

    SciTech Connect

    Miller, Naomi J.; Koltai, Rita; McGowan, Terry

    2013-12-31

    This GATEWAY report discusses the problems of pedestrian lighting that occur with all technologies with a focus on the unique optical options and opportunities offered by LEDs through the findings from two pedestrian-focused projects, one at Stanford University in California, and one at the Chautauqua Institution in upstate New York. Incorporating user feedback this report reviews the tradeoffs that must be weighed among visual comfort, color, visibility, efficacy and other factors to stimulate discussion among specifiers, users, energy specialists, and in industry in hopes that new approaches, metrics, and standards can be developed to support pedestrian-focused communities, while reducing energy use.

  14. Teach Children Pedestrian Safety.

    ERIC Educational Resources Information Center

    Faber, Marilyn M.

    1997-01-01

    Provides advice on teaching children safe pedestrian and bicycling skills to reduce accidents caused by mistakes made in crossing streets. Provides an interactive safe-walker's story, tips for walking safely, step-by-step instructions for safe street crossing, bicycle safety information, a quiz for safe biking, and guidelines to ensure a proper…

  15. Pedestrians Injury Patterns in Ghana

    PubMed Central

    Damsere-Derry, James; Ebel, Beth E.; Mock, Charles N.; Afukaar, Francis; Donkor, Peter

    2010-01-01

    Objective To establish the associations between pedestrian injury and explanatory variables such as vehicular characteristics, temporal trends, and road environment. Methods A retrospective analysis of de-identified pedestrian crash data between 2002 and 2006 was conducted using the Building & Road Research Institute’s crash data bank. We estimated the odds ratios associated with casualty fatalities using a multinomial logistic regression. Results There were 812 pedestrian casualties reported, out of which 33% were fatal, 45% sustained serious injuries requiring hospitalization, and 22% were slightly injured but were not hospitalized. Crossing the roadway accounted for over 70% of all pedestrians deaths. Whereas fatalities in 2002 and 2003 were statistically indistinguishable from those of 2004(p>0.05), in comparison with 2004, there were significantly fewer fatalities in 2005 and 2006 (78% and 65% reduction respectively). According to police report, the probability that a pedestrian fatality occurring in Ghana is attributable to excessive speeding is 65%. The adjusted odds ratio of pedestrian fatality associated with speeding compared with driver inattentiveness was 3.6(95% CI: 2.5 to 5.2). It was also observed that generally, lighter vehicular masses were associated with lower pedestrian fatalities. Compared with buses, pedestrians were less likely to die when struck by private cars (52%), pick-up trucks (57%), and motorcycles (86%). Conclusion Pedestrian death remains the leading cause of fatality among urban road users in Ghana. Risk factors associated with pedestrian fatality include being hit by heavy vehicles, speeding, and roadside activities such as street hawking, jaywalking and nighttime walking. Steps which may contribute to reducing pedestrian fatalities include measures to reduce vehicles speeds in settlements, providing traffic medians and lighting streets in settlements, and discouraging street and roadside activities such as hawking. PMID

  16. Analyzing fault in pedestrian-motor vehicle crashes in North Carolina.

    PubMed

    Ulfarsson, Gudmundur F; Kim, Sungyop; Booth, Kathleen M

    2010-11-01

    Crashes between pedestrians and motor vehicles are an important traffic safety concern. This paper explores the assignment of fault in such crashes, where observed factors are associated with pedestrian at fault, driver at fault, or both at fault. The analysis is based on police reported crash data for 1997 through 2000 in North Carolina, U.S.A. The results show that pedestrians are found at fault in 59% of the crashes, drivers in 32%, and both are found at fault in 9%. The results indicate drivers need to take greater notice of pedestrians when drivers are turning, merging, and backing up as these are some of the prime factors associated with the driver being found at fault in a crash. Pedestrians must apply greater caution when crossing streets, waiting to cross, and when walking along roads, as these are correlated with pedestrians being found at fault. The results suggest a need for campaigns focused on positively affecting pedestrian street-crossing behavior in combination with added jaywalking enforcement. The results also indicate that campaigns to increase the use of pedestrian visibility improvements at night can have a significant positive impact on traffic safety. Intoxication is a concern and the results show that it is not only driver intoxication that is affecting safety, but also pedestrian intoxication. The findings show in combination with other research in the field, that results from traffic safety studies are not necessarily transferable between distant geographic locations, and that location-specific safety research needs to take place. It is also important to further study the specific effects of the design of the pedestrian environment on safety, e.g. crosswalk spacing, signal timings, etc., which together may affect pedestrian safety and pedestrian behavior. PMID:20728631

  17. Rapid detection and identification of pedestrian impacts using a distributed sensor network

    NASA Astrophysics Data System (ADS)

    Kim, Andrew C.; Chang, Fu-Kuo

    2005-05-01

    Pedestrian fatalities from automobile accidents often occur as a result of head injuries suffered from impacts with an automobile front end. Active pedestrian protection systems with proper pedestrian recognition algorithms can protect pedestrians from such head trauma. An investigation was conducted to assess the feasibility of using a network of piezoelectric sensors mounted on the front bumper beam of an automobile to discriminate between impacts with "pedestrian" and "non-pedestrian" objects. This information would be used to activate a safety device (e.g., external airbag or pop-up hood) to provide protection for the vulnerable pedestrian. An analytical foundation for the object-bumper impact problem will be presented, as well as the classical beam impact theory. The mechanical waves that propagate in the structure from an external impact contain a wealth of information about the specifics of a particular impact -- object mass, size, impact speed, etc. -- but most notably the object stiffness, which identifies the impacted object. Using the frequency content of the sensor signals, it can be shown that impacts with a "pedestrian" object of varying size, weight, and speed can be easily differentiated from impacts with other "non-pedestrian" objects. Simulation results will illustrate this phenomenon, and experimental tests will verify the results. A comprehensive series of impact tests were performed for validation, using both a stationary front bumper with a drop-pendulum impactor and a moving car with stationary impact objects. Results from both tests will be presented.

  18. Nuclear Receptor Signaling Atlas: Opening Access to the Biology of Nuclear Receptor Signaling Pathways.

    PubMed

    Becnel, Lauren B; Darlington, Yolanda F; Ochsner, Scott A; Easton-Marks, Jeremy R; Watkins, Christopher M; McOwiti, Apollo; Kankanamge, Wasula H; Wise, Michael W; DeHart, Michael; Margolis, Ronald N; McKenna, Neil J

    2015-01-01

    Signaling pathways involving nuclear receptors (NRs), their ligands and coregulators, regulate tissue-specific transcriptomes in diverse processes, including development, metabolism, reproduction, the immune response and neuronal function, as well as in their associated pathologies. The Nuclear Receptor Signaling Atlas (NURSA) is a Consortium focused around a Hub website (www.nursa.org) that annotates and integrates diverse 'omics datasets originating from the published literature and NURSA-funded Data Source Projects (NDSPs). These datasets are then exposed to the scientific community on an Open Access basis through user-friendly data browsing and search interfaces. Here, we describe the redesign of the Hub, version 3.0, to deploy "Web 2.0" technologies and add richer, more diverse content. The Molecule Pages, which aggregate information relevant to NR signaling pathways from myriad external databases, have been enhanced to include resources for basic scientists, such as post-translational modification sites and targeting miRNAs, and for clinicians, such as clinical trials. A portal to NURSA's Open Access, PubMed-indexed journal Nuclear Receptor Signaling has been added to facilitate manuscript submissions. Datasets and information on reagents generated by NDSPs are available, as is information concerning periodic new NDSP funding solicitations. Finally, the new website integrates the Transcriptomine analysis tool, which allows for mining of millions of richly annotated public transcriptomic data points in the field, providing an environment for dataset re-use and citation, bench data validation and hypothesis generation. We anticipate that this new release of the NURSA database will have tangible, long term benefits for both basic and clinical research in this field. PMID:26325041

  19. Nuclear Receptor Signaling Atlas: Opening Access to the Biology of Nuclear Receptor Signaling Pathways

    PubMed Central

    Becnel, Lauren B.; Darlington, Yolanda F.; Ochsner, Scott A.; Easton-Marks, Jeremy R.; Watkins, Christopher M.; McOwiti, Apollo; Kankanamge, Wasula H.; Wise, Michael W.; DeHart, Michael; Margolis, Ronald N.; McKenna, Neil J.

    2015-01-01

    Signaling pathways involving nuclear receptors (NRs), their ligands and coregulators, regulate tissue-specific transcriptomes in diverse processes, including development, metabolism, reproduction, the immune response and neuronal function, as well as in their associated pathologies. The Nuclear Receptor Signaling Atlas (NURSA) is a Consortium focused around a Hub website (www.nursa.org) that annotates and integrates diverse ‘omics datasets originating from the published literature and NURSA-funded Data Source Projects (NDSPs). These datasets are then exposed to the scientific community on an Open Access basis through user-friendly data browsing and search interfaces. Here, we describe the redesign of the Hub, version 3.0, to deploy “Web 2.0” technologies and add richer, more diverse content. The Molecule Pages, which aggregate information relevant to NR signaling pathways from myriad external databases, have been enhanced to include resources for basic scientists, such as post-translational modification sites and targeting miRNAs, and for clinicians, such as clinical trials. A portal to NURSA’s Open Access, PubMed-indexed journal Nuclear Receptor Signaling has been added to facilitate manuscript submissions. Datasets and information on reagents generated by NDSPs are available, as is information concerning periodic new NDSP funding solicitations. Finally, the new website integrates the Transcriptomine analysis tool, which allows for mining of millions of richly annotated public transcriptomic data points in the field, providing an environment for dataset re-use and citation, bench data validation and hypothesis generation. We anticipate that this new release of the NURSA database will have tangible, long term benefits for both basic and clinical research in this field. PMID:26325041

  20. Validity of instruments to assess students' travel and pedestrian safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Safe Routes to School (SRTS) programs are designed to make walking and bicycling to school,safe and accessible for children. Despite their growing popularity, few validated measures exist for assessing important outcomes such as type of student transport or pedestrian safety behaviors. This research...

  1. Development of a portable bicycle/pedestrian monitoring system for safety enhancement

    NASA Astrophysics Data System (ADS)

    Usher, Colin; Daley, W. D. R.

    2015-03-01

    Pedestrians involved in roadway accidents account for nearly 12 percent of all traffic fatalities and 59,000 injuries each year. Most injuries occur when pedestrians attempt to cross roads, and there have been noted differences in accident rates midblock vs. at intersections. Collecting data on pedestrian behavior is a time consuming manual process that is prone to error. This leads to a lack of quality information to guide the proper design of lane markings and traffic signals to enhance pedestrian safety. Researchers at the Georgia Tech Research Institute are developing and testing an automated system that can be rapidly deployed for data collection to support the analysis of pedestrian behavior at intersections and midblock crossings with and without traffic signals. This system will analyze the collected video data to automatically identify and characterize the number of pedestrians and their behavior. It consists of a mobile trailer with four high definition pan-tilt cameras for data collection. The software is custom designed and uses state of the art commercial pedestrian detection algorithms. We will be presenting the system hardware and software design, challenges, and results from the preliminary system testing. Preliminary results indicate the ability to provide representative quantitative data on pedestrian motion data more efficiently than current techniques.

  2. Constructal design of pedestrian evacuation from an area

    NASA Astrophysics Data System (ADS)

    Lui, C. H.; Fong, N. K.; Lorente, S.; Bejan, A.; Chow, W. K.

    2013-01-01

    Pedestrian movement occurs in evolutionary patterns the effect of which is to facilitate the access of people into and out of living spaces (areas, volumes). In this paper, we rely on the philosophy of Constructal design as applied physics, in order to uncover two fundamental features of evolutionary design for pedestrian evacuation from rectangular areas (e.g., lecture halls with seated occupants). First, the paper shows analytically that the aspect ratio of the floor area can be selected such that the total evacuation time is minimal. Second, the shape of the floor area of each aisle can be tapered such that the total evacuation time is decreased further. These two architectural features are confirmed by means of extensive and systematic numerical simulations of pedestrian evacuation, by using two numerical packages (Simulex and FDS + Evac).

  3. 36 CFR 504.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... traffic. 504.13 Section 504.13 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.13 Vehicular and pedestrian traffic... times and shall comply with the signals and directions of the guards and all posted traffic signs....

  4. 36 CFR 504.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... traffic. 504.13 Section 504.13 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.13 Vehicular and pedestrian traffic... times and shall comply with the signals and directions of the guards and all posted traffic signs....

  5. 36 CFR 504.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... traffic. 504.13 Section 504.13 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.13 Vehicular and pedestrian traffic... times and shall comply with the signals and directions of the guards and all posted traffic signs....

  6. 36 CFR 504.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... traffic. 504.13 Section 504.13 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.13 Vehicular and pedestrian traffic... times and shall comply with the signals and directions of the guards and all posted traffic signs....

  7. 36 CFR 504.13 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... traffic. 504.13 Section 504.13 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND REGULATIONS GOVERNING SMITHSONIAN INSTITUTION BUILDINGS AND GROUNDS § 504.13 Vehicular and pedestrian traffic... times and shall comply with the signals and directions of the guards and all posted traffic signs....

  8. Use of Google Street View to Assess Environmental Contributions to Pedestrian Injury

    PubMed Central

    Mooney, Stephen J.; DiMaggio, Charles J.; Lovasi, Gina S.; Neckerman, Kathryn M.; Bader, Michael D. M.; Teitler, Julien O.; Sheehan, Daniel M.; Jack, Darby W.

    2016-01-01

    Objectives. To demonstrate an information technology–based approach to assess characteristics of streets and intersections associated with injuries that is less costly and time-consuming than location-based studies of pedestrian injury. Methods. We used imagery captured by Google Street View from 2007 to 2011 to assess 9 characteristics of 532 intersections within New York City. We controlled for estimated pedestrian count and estimated the relation between intersections’ characteristics and frequency of injurious collisions. Results. The count of pedestrian injuries at intersections was associated with the presence of marked crosswalks (80% increase; 95% confidence interval [CI] = 2%, 218%), pedestrian signals (156% increase; 95% CI = 69%, 259%), nearby billboards (42% increase; 95% CI = 7%, 90%), and bus stops (120% increase; 95% CI = 51%, 220%). Injury incidence per pedestrian was lower at intersections with higher estimated pedestrian volumes. Conclusions. Consistent with in-person study observations, the information-technology approach found traffic islands, visual advertising, bus stops, and crosswalk infrastructures to be associated with elevated counts of pedestrian injury in New York City. Virtual site visits for pedestrian injury control studies are a viable and informative methodology. PMID:26794155

  9. Capacity Estimation Model for Signalized Intersections under the Impact of Access Point.

    PubMed

    Zhao, Jing; Li, Peng; Zhou, Xizhao

    2016-01-01

    Highway Capacity Manual 2010 provides various factors to adjust the base saturation flow rate for the capacity analysis of signalized intersections. No factors, however, is considered for the potential change of signalized intersections capacity caused by the access point closeing to the signalized intersection. This paper presented a theoretical model to estimate the lane group capacity at signalized intersections with the consideration of the effects of access points. Two scenarios of access point locations, upstream or downstream of the signalized intersection, and impacts of six types of access traffic flow are taken into account. The proposed capacity model was validated based on VISSIM simulation. Results of extensive numerical analysis reveal the substantial impact of access point on the capacity, which has an inverse correlation with both the number of major street lanes and the distance between the intersection and access point. Moreover, among the six types of access traffic flows, the access traffic flow 1 (right-turning traffic from major street), flow 4 (left-turning traffic from access point), and flow 5 (left-turning traffic from major street) cause a more significant effect on lane group capacity than others. Some guidance on the mitigation of the negative effect is provided for practitioners. PMID:26726998

  10. Capacity Estimation Model for Signalized Intersections under the Impact of Access Point

    PubMed Central

    Zhao, Jing; Li, Peng; Zhou, Xizhao

    2016-01-01

    Highway Capacity Manual 2010 provides various factors to adjust the base saturation flow rate for the capacity analysis of signalized intersections. No factors, however, is considered for the potential change of signalized intersections capacity caused by the access point closeing to the signalized intersection. This paper presented a theoretical model to estimate the lane group capacity at signalized intersections with the consideration of the effects of access points. Two scenarios of access point locations, upstream or downstream of the signalized intersection, and impacts of six types of access traffic flow are taken into account. The proposed capacity model was validated based on VISSIM simulation. Results of extensive numerical analysis reveal the substantial impact of access point on the capacity, which has an inverse correlation with both the number of major street lanes and the distance between the intersection and access point. Moreover, among the six types of access traffic flows, the access traffic flow 1 (right-turning traffic from major street), flow 4 (left-turning traffic from access point), and flow 5 (left-turning traffic from major street) cause a more significant effect on lane group capacity than others. Some guidance on the mitigation of the negative effect is provided for practitioners. PMID:26726998

  11. Fatal pedestrian-bicycle collisions.

    PubMed

    Graw, M; König, H G

    2002-05-23

    Although, fatal collisions between pedestrians and bicycles are relatively rare, they are still of forensic relevance because of the need to explore the circumstances of the accident. Based on three reconstructed cases, situation and injury patterns are presented that might prove useful in future cases: usually the person causing the accident is the cyclist while the pedestrian generally suffers more severe injuries; the situation at the site of accident is important for its reconstruction: end location of the persons involved in the accident, injuries and traces on pedestrians and cyclists, traces at the site of accident and on the bicycle; because of the lack of pre-crash traces and any eyewitness accounts, the pedestrian's injuries are the best starting point for the reconstruction of the accident; a characteristic wound on the lower leg of the pedestrian that reveals the initial impact between the front wheel and the leg is crucial not because of its seriousness, but because of its external morphology; the injuries that can be expected by the following impact between body and handlebar are unspecific and only minor; the most severe injuries to the pedestrian as a result of the accident are caused secondarily by falling and hitting the head on the road; the fall of the cyclist, however, corresponds to a throw-off followed by a sliding phase with less impact load when the head hits the ground [maximum abbreviated injury scale 1 (MAIS 1)]; the cyclists involved are mainly younger persons on fashionable bicycles (here: mountain bikes); in the great majority of cases, the injured pedestrians are frail, elderly people with a lower tolerance of trauma. PMID:12062948

  12. Code division multiple access signaling for modulated reflector technology

    DOEpatents

    Briles, Scott D.

    2012-05-01

    A method and apparatus for utilizing code division multiple access in modulated reflectance transmissions comprises the steps of generating a phase-modulated reflectance data bit stream; modifying the modulated reflectance data bit stream; providing the modified modulated reflectance data bit stream to a switch that connects an antenna to an infinite impedance in the event a "+1" is to be sent, or connects the antenna to ground in the event a "0" or a "-1" is to be sent.

  13. Pedestrian flow through multiple bottlenecks

    NASA Astrophysics Data System (ADS)

    Ezaki, Takahiro; Yanagisawa, Daichi; Nishinari, Katsuhiro

    2012-08-01

    We investigate the dynamics of the evacuation process with multiple bottlenecks using the floor field model. To deal with this problem, we first focus on a part of the system and report its microscopic behavior. The system is controlled by parameters of inflow and the competitiveness of the pedestrians, and large inflow leads to a congested situation. Through simulations, the metastable state induced by conflicts of pedestrians is observed. The metastability is related to the phase transition from free flow to congestion. The critical condition of the transition is theoretically derived. In addition, we give simulation results of situations with multiple bottlenecks. They imply that local improvement of pedestrian flow sometimes adversely affects the total evacuation time, and that the total optimization of the system is not straightforward.

  14. Child pedestrian casualties and deprivation.

    PubMed

    Green, James; Muir, Helen; Maher, Mike

    2011-05-01

    The existence of an association between child pedestrian accidents and socio-economic deprivation in Great Britain is well established. The factors driving this association are complex and difficult to isolate. This study uses accident prediction models to investigate the links between child pedestrian casualties and a range of environmental and socio-economic factors commonly linked to deprived areas and people. Separate models are constructed relating to the areas in which the children become casualties, and the areas in which the children reside. Significant socio-economic factors include: single-parenthood, reliance on income support, and crime; and environmental factors include domestic garden area, junction density and pedestrian and vehicular flow density. The study found that factors pertaining to the local environment were more prevalent in the models considering accident locations, whilst socio-economic factors were of greater influence in the residency model. PMID:21376859

  15. Modeling the impact of pedestrian behavior diversity on traffic dynamics at a crosswalk with push button

    NASA Astrophysics Data System (ADS)

    Xie, Dong-Fan; Zhao, Xiao-Mei; Li, Xin-Gang; Zhu, Tai-Lang

    2016-01-01

    Crosswalk with push button is prevalent in lots of cities for the purpose of promoting the efficiency of the crosswalk, and thus the delays of both vehicles and pedestrians can be reduced. This strategy has been confirmed to be effective in several developed countries. However, it is a pity that application of push button is aborted in some cities in China. In this work, diverse behaviors of vehicles and pedestrians are analyzed and discussed. Then, a microscopic model is developed by incorporating the interaction between vehicles and pedestrians. Numerical simulations are performed to reveal the characteristics of traffic flow and the efficiency of the signal control strategy. Also, the impacts of risker proportion and button reaction time, as well as the impacts of various behaviors as mass behavior, the patience of pedestrian and push button habit are investigated. It is expected that the results will be helpful to the strategy design of a signalized crosswalk in such developing countries as China.

  16. Working Concept of Accessibility

    PubMed Central

    Schroeder, Bastian J.; Rouphail, Nagui M.; Hughes, Ronald G.

    2010-01-01

    This research presents an analysis framework and associated performance measures for quantifying the accessibility of pedestrian crossings at modern roundabouts for pedestrians who are blind. The measures, developed under two ongoing national research projects, NCHRP Project 3-78A and a bioengineering research grant from the National Institutes of Health–National Eye Institute, attempt to isolate the components of the crossing task for a blind pedestrian into computable and replicable quantities that allow the comparison of accessibility across individuals or sites. The framework differentiates between crossing opportunities in the form of yields and crossable gaps and the utilization of these opportunities by the pedestrian. It further accounts for the amount of delay and risk involved in the crossing. The analysis framework and measures are demonstrated for two single-lane roundabouts in North Carolina evaluated under the aforementioned research projects. The application shows that the accessibility of a pedestrian crossing to a blind pedestrian is characterized by a combination of different measures and further depends on crossing geometry, traffic volume, driver behavior, and the travel skills and risk-taking behavior of the individual. With successful demonstration at roundabout crosswalks, the analysis framework is hypothesized to have broader application to unsignalized pedestrian crossings, including midblock locations. PMID:20664802

  17. A rapid method for identifying and characterizing structural impacts using distributed sensors: An application for automotive pedestrian protection

    NASA Astrophysics Data System (ADS)

    Kim, Andrew C.

    This research is motivated by recent activity to improve automotive safety, especially for pedestrians. In many parts of the world today, injuries and fatalities from road accidents are a significant problem. Safety features such as seat restraints and air bags provide considerable levels of protection for car occupants; however, no such protective measures currently exist for pedestrians. Drawing upon the success and effectiveness of occupant air bag systems, current research aims to develop similar devices for pedestrians. These active pedestrian protection systems deploy a safety feature such as an external air bag when a pedestrian is hit by a vehicle. Contact with the front bumper induces a body rotation that may result in a violent head collision. The deployable safety device provides a cushioning surface for the vulnerable pedestrian during impact. The challenge of such a system is an effective sensory unit that can rapidly and correctly discriminate pedestrian impacts from non-pedestrian ones. The fast kinematics of the automobile-pedestrian impact leaves a minimal amount of time for signal processing and computation. This research study focuses on a discrimination scheme that satisfies both the time and accuracy requirements for a proposed sensory system for pedestrian protection. A unique methodology was developed to identify structural impacts using dominant frequency features extracted from sensory data. Contact sensors mounted on the front bumper of an automobile measure the strain response from an impact event. The dominant frequencies obtained from these sensor signals are greatly influenced by the impact object's properties and can be used to discriminate between different objects. Extensive tests were conducted to gather sensor data and validate the proposed methodology and impact discrimination algorithm. Results of the impact tests indicate that the approach is sound, and the sensory system effectively identifies "pedestrian" impacts within a

  18. Simulation of counterflow pedestrian dynamics using spheropolygons

    NASA Astrophysics Data System (ADS)

    Alonso-Marroquín, Fernando; Busch, Jonathan; Chiew, Coraline; Lozano, Celia; Ramírez-Gómez, Álvaro

    2014-12-01

    Pedestrian dynamic models are typically designed for comfortable walking or slightly congested conditions and typically use a single disk or combination of three disks for the shape of a pedestrian. Under crowd conditions, a more accurate pedestrian shape has advantages over the traditional single or three-disks model. We developed a method for simulating pedestrian dynamics in a large dense crowd of spheropolygons adapted to the cross section of the chest and arms of a pedestrian. Our numerical model calculates pedestrian motion from Newton's second law, taking into account viscoelastic contact forces, contact friction, and ground-reaction forces. Ground-reaction torque was taken to arise solely from the pedestrians' orientation toward their preferred destination. Simulations of counterflow pedestrians dynamics in corridors were used to gain insight into a tragic incident at the Madrid Arena pavilion in Spain, where five girls were crushed to death. The incident took place at a Halloween Celebration in 2012, in a long, densely crowded hallway used as entrance and exit at the same time. Our simulations reconstruct the mechanism of clogging in the hallway. The hypothetical case of a total evacuation order was also investigated. The results highlights the importance of the pedestrians' density and the effect of counterflow in the onset of avalanches and clogging and provides an estimation of the number of injuries based on a calculation of the contact-force network between the pedestrians.

  19. Simulation of counterflow pedestrian dynamics using spheropolygons.

    PubMed

    Alonso-Marroquín, Fernando; Busch, Jonathan; Chiew, Coraline; Lozano, Celia; Ramírez-Gómez, Álvaro

    2014-12-01

    Pedestrian dynamic models are typically designed for comfortable walking or slightly congested conditions and typically use a single disk or combination of three disks for the shape of a pedestrian. Under crowd conditions, a more accurate pedestrian shape has advantages over the traditional single or three-disks model. We developed a method for simulating pedestrian dynamics in a large dense crowd of spheropolygons adapted to the cross section of the chest and arms of a pedestrian. Our numerical model calculates pedestrian motion from Newton's second law, taking into account viscoelastic contact forces, contact friction, and ground-reaction forces. Ground-reaction torque was taken to arise solely from the pedestrians' orientation toward their preferred destination. Simulations of counterflow pedestrians dynamics in corridors were used to gain insight into a tragic incident at the Madrid Arena pavilion in Spain, where five girls were crushed to death. The incident took place at a Halloween Celebration in 2012, in a long, densely crowded hallway used as entrance and exit at the same time. Our simulations reconstruct the mechanism of clogging in the hallway. The hypothetical case of a total evacuation order was also investigated. The results highlights the importance of the pedestrians' density and the effect of counterflow in the onset of avalanches and clogging and provides an estimation of the number of injuries based on a calculation of the contact-force network between the pedestrians. PMID:25615220

  20. International trends in pedestrian injury mortality.

    PubMed Central

    Roberts, I G

    1993-01-01

    Trends in pedestrian injury mortality for children aged 0-4 and 5-14 for England and Wales, Denmark, Sweden, the USA, and New Zealand were examined from 1968 onwards. While there has been a reduction in the pedestrian mortality in all these countries, there are striking international differences in the extent of these reductions. Denmark has achieved the greatest fall in mortality with the smallest decrease seen in New Zealand. Countries which have experienced major decreases in pedestrian mortality are distinguished by having placed greater emphasis on environmentally based prevention strategies rather than pedestrian skills education. PMID:8481041

  1. Code extraction from encoded signal in time-spreading optical code division multiple access.

    PubMed

    Si, Zhijian; Yin, Feifei; Xin, Ming; Chen, Hongwei; Chen, Minghua; Xie, Shizhong

    2010-01-15

    A vulnerability that allows eavesdroppers to extract the code from the waveform of the noiselike encoded signal of an isolated user in a standard time-spreading optical code division multiple access communication system using bipolar phase code is experimentally demonstrated. The principle is based on fine structure in the encoded signal. Each dip in the waveform corresponds to a transition of the bipolar code. Eavesdroppers can get the code by analyzing the chip numbers between any two transitions; then a decoder identical to the legal user's can be fabricated, and they can get the properly decoded signal. PMID:20081977

  2. Adaptive coded spreading OFDM signal for dynamic-λ optical access network

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Zhang, Lijia; Xin, Xiangjun

    2015-12-01

    This paper proposes and experimentally demonstrates a novel adaptive coded spreading (ACS) orthogonal frequency division multiplexing (OFDM) signal for dynamic distributed optical ring-based access network. The wavelength can be assigned to different remote nodes (RNs) according to the traffic demand of optical network unit (ONU). The ACS can provide dynamic spreading gain to different signals according to the split ratio or transmission length, which offers flexible power budget for the network. A 10×13.12 Gb/s OFDM access with ACS is successfully demonstrated over two RNs and 120 km transmission in the experiment. The demonstrated method may be viewed as one promising for future optical metro access network.

  3. Factors influencing injury severity of motor vehicle-crossing pedestrian crashes in rural Connecticut.

    PubMed

    Zajac, Sylvia S; Ivan, John N

    2003-05-01

    The ordered probit model was used to evaluate the effect of roadway and area type features on injury severity of pedestrian crashes in rural Connecticut. Injury severity was coded on the KABCO scale and crashes were limited to those in which the pedestrians were attempting to cross two-lane highways that were controlled by neither stop signs nor traffic signals. Variables that significantly influenced pedestrian injury severity were clear roadway width (the distance across the road including lane widths and shoulders, but excluding the area occupied by on-street parking), vehicle type, driver alcohol involvement, pedestrian age 65 years or older, and pedestrian alcohol involvement. Seven area types were identified: downtown, compact residential, village, downtown fringe, medium-density commercial, low-density commercial, and low-density residential. Two groups of these area types were found to experience significantly different injury severities. Downtown, compact residential, and medium- and low-density commercial areas generally experienced lower pedestrian injury severity than village, downtown fringe, and low-density residential areas. PMID:12643954

  4. Pedestrian Crossings. USMES Teacher Resource Book.

    ERIC Educational Resources Information Center

    Brady, Ray, Jr., Ed.; Arbetter, Carolyn Clinton, Ed.

    This USMES unit challenges students to recommend and try to have a change made which would improve the safety and convenience of a pedestrian crossing near the school. The teacher resource book for the Pedestrian Crossings unit contains five sections. The first section describes the USMES approach to student-initiated investigations of real…

  5. Separability between pedestrians in hyperspectral imagery.

    PubMed

    Herweg, Jared; Kerekes, John; Eismann, Michael

    2013-02-20

    The popularity of hyperspectral imaging (HSI) in remote sensing continues to lead to it being adapted in novel ways to overcome challenging imaging problems. This paper reports on research efforts exploring the phenomenology of using HSI as an aid in detecting and tracking human pedestrians. An assessment of the likelihood of distinguishing between pedestrians based on the measured spectral reflectance of observable materials and the presence of noise is presented. The assessments included looking at the spectral separation between pedestrian material subregions using different spectral-reflectance regions within the full range (450-2500 nm), as well as when the spectral content of the pedestrian subregions are combined. In addition to the pedestrian spectral-reflectance data analysis, the separability of pedestrian subregions in remotely sensed hyperspectral images was assessed using a unique data set garnered as part of this work. Results indicated that skin was the least distinguishable material between pedestrians using the spectral Euclidean distance metric. The clothing, especially the shirt, offered the most salient feature for distinguishing the pedestrian. Additionally, significant spectral separability performance is realized when combining the reflectance information of two or more subregions. PMID:23435007

  6. Waiting pedestrians in the social force model

    NASA Astrophysics Data System (ADS)

    Johansson, Fredrik; Peterson, Anders; Tapani, Andreas

    2015-02-01

    Microscopic simulation of pedestrian traffic is an important and increasingly popular method to evaluate the performance of existing or proposed infrastructure. The social force model is a common model in simulations, describing the dynamics of pedestrian crowds given the goals of the simulated pedestrians encoded as their preferred velocities. The main focus of the literature has so far been how to choose the preferred velocities to produce realistic dynamic route choices for pedestrians moving through congested infrastructure. However, limited attention has been given the problem of choosing the preferred velocity to produce other behaviors, such as waiting, commonly occurring at, e.g., public transport interchange stations. We hypothesize that: (1) the inclusion of waiting pedestrians in a simulated scenario will significantly affect the level of service for passing pedestrians, and (2) the details of the waiting model affect the predicted level of service, that is, it is important to choose an appropriate model of waiting. We show that the treatment of waiting pedestrians have a significant impact on simulations of pedestrian traffic. We do this by introducing a series of extensions to the social force model to produce waiting behavior, and provide predictions of the model extensions that highlight their differences. We also present a sensitivity analysis and provide sufficient criteria for stability.

  7. Multilevel models for evaluating the risk of pedestrian-motor vehicle collisions at intersections and mid-blocks.

    PubMed

    Quistberg, D Alex; Howard, Eric J; Ebel, Beth E; Moudon, Anne V; Saelens, Brian E; Hurvitz, Philip M; Curtin, James E; Rivara, Frederick P

    2015-11-01

    Walking is a popular form of physical activity associated with clear health benefits. Promoting safe walking for pedestrians requires evaluating the risk of pedestrian-motor vehicle collisions at specific roadway locations in order to identify where road improvements and other interventions may be needed. The objective of this analysis was to estimate the risk of pedestrian collisions at intersections and mid-blocks in Seattle, WA. The study used 2007-2013 pedestrian-motor vehicle collision data from police reports and detailed characteristics of the microenvironment and macroenvironment at intersection and mid-block locations. The primary outcome was the number of pedestrian-motor vehicle collisions over time at each location (incident rate ratio [IRR] and 95% confidence interval [95% CI]). Multilevel mixed effects Poisson models accounted for correlation within and between locations and census blocks over time. Analysis accounted for pedestrian and vehicle activity (e.g., residential density and road classification). In the final multivariable model, intersections with 4 segments or 5 or more segments had higher pedestrian collision rates compared to mid-blocks. Non-residential roads had significantly higher rates than residential roads, with principal arterials having the highest collision rate. The pedestrian collision rate was higher by 9% per 10 feet of street width. Locations with traffic signals had twice the collision rate of locations without a signal and those with marked crosswalks also had a higher rate. Locations with a marked crosswalk also had higher risk of collision. Locations with a one-way road or those with signs encouraging motorists to cede the right-of-way to pedestrians had fewer pedestrian collisions. Collision rates were higher in locations that encourage greater pedestrian activity (more bus use, more fast food restaurants, higher employment, residential, and population densities). Locations with higher intersection density had a lower

  8. Accessibility

    MedlinePlus

    ... www.nlm.nih.gov/medlineplus/accessibility.html MedlinePlus Accessibility To use the sharing features on this page, ... Subscribe to RSS Follow us Disclaimers Copyright Privacy Accessibility Quality Guidelines Viewers & Players MedlinePlus Connect for EHRs ...

  9. Gigabit Ethernet signal transmission using asynchronous optical code division multiple access.

    PubMed

    Ma, Philip Y; Fok, Mable P; Shastri, Bhavin J; Wu, Ben; Prucnal, Paul R

    2015-12-15

    We propose and experimentally demonstrate a novel architecture for interfacing and transmitting a Gigabit Ethernet (GbE) signal using asynchronous incoherent optical code division multiple access (OCDMA). This is the first such asynchronous incoherent OCDMA system carrying GbE data being demonstrated to be working among multi-users where each user is operating with an independent clock/data rate and is granted random access to the network. Three major components, the GbE interface, the OCDMA transmitter, and the OCDMA receiver are discussed in detail. The performance of the system is studied and characterized through measuring eye diagrams, bit-error rate and packet loss rate in real-time file transfer. Our Letter also addresses the near-far problem and realizes asynchronous transmission and detection of signal. PMID:26670529

  10. Retina-on-a-chip: a microfluidic platform for point access signaling studies.

    PubMed

    Dodson, Kirsten H; Echevarria, Franklin D; Li, Deyu; Sappington, Rebecca M; Edd, Jon F

    2015-12-01

    We report on a microfluidic platform for culture of whole organs or tissue slices with the capability of point access reagent delivery to probe the transport of signaling events. Whole mice retina were maintained for multiple days with negative pressure applied to tightly but gently bind the bottom of the retina to a thin poly-(dimethylsiloxane) membrane, through which twelve 100 μm diameter through-holes served as fluidic access points. Staining with toluidine blue, transport of locally applied cholera toxin beta, and transient response to lipopolysaccharide in the retina demonstrated the capability of the microfluidic platform. The point access fluidic delivery capability could enable new assays in the study of various kinds of excised tissues, including retina. PMID:26559199

  11. Retina-on-a-chip: a microfluidic platform for point access signaling studies

    PubMed Central

    Dodson, Kirsten H.; Echevarria, Franklin D.; Li, Deyu; Sappington, Rebecca M.; Edd, Jon F.

    2016-01-01

    We report on a microfluidic platform for culture of whole organs or tissue slices with the capability of point access reagent delivery to probe the transport of signaling events. Whole mice retina were maintained for multiple days with negative pressure applied to tightly but gently bind the bottom of the retina to a thin poly-(dimethylsiloxane) membrane, through which twelve 100 μm diameter through-holes served as fluidic access points. Staining with toluidine blue, transport of locally applied cholera toxin beta, and transient response to lipopolysaccharide in the retina demonstrated the capability of the microfluidic platform. The point access fluidic delivery capability could enable new assays in the study of various kinds of excised tissues, including retina. PMID:26559199

  12. Effects of Picture Prompts Delivered by a Video iPod on Pedestrian Navigation

    ERIC Educational Resources Information Center

    Kelley, Kelly R.; Test, David W.; Cooke, Nancy L.

    2013-01-01

    Transportation access is a major contributor to independence, productivity, and societal inclusion for individuals with intellectual and development disabilities (IDD). This study examined the effects of pedestrian navigation training using picture prompts displayed through a video iPod on travel route completion with 4 adults and IDD. Results…

  13. 76 FR 52046 - Final Policy Statement on the Eligibility of Pedestrian and Bicycle Improvements Under Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-19

    ... of Joint Development Projects under Federal Transit Law at 72 FR 5788. B. Transit Enhancement... Investment Projects, 75 FR 31383 (June 3, 2010). ] F. Access to Public Transportation for Individuals With... Statement on the Eligibility of Pedestrian and Bicycle Improvements under Federal Transit Law, 74 FR...

  14. PHOTOVOICE: Reducing pedestrian injuries in children.

    PubMed

    Van Oss, Tracy; Quinn, Danielle; Viscosi, Pauline; Bretscher, Kristen

    2013-01-01

    Pedestrian injury is the second leading cause of injury related death for children. The purpose of this research project was to determine the effectiveness of pedestrian and road traffic safety education with children, as part of the Walk This Way program through Safe Kids USA. Through the implementation of PHOTOVOICE, a project that captured children's narratives coinciding with a photograph, children engaged in community exploration to identify pedestrian hazards in their communities and explore possible solutions utilizing their photography and narrations. Children participated in an engaging educational session, a community fieldtrip, and reflection. Results concluded that, despite a small increase in post test scores, an increase in awareness of hazards in the community and successful identification of community hazards was achieved. The goal of this research project was determine the effectiveness of a hands-on pedestrian and road traffic safety educational program with children. The results of this research project will be integrated with similar projects completed across the country through the program Walk This Way with Safe Kids USA. Both this research project and the Walk This Way program aim to promote behavior change in children and create safer communities to reduce pedestrian related injury. The overall goal of this research project andthe Walk This Way program is to increase education on a national level in regards to pedestrian safety for children and provide a basis for lobbying for public policy changes pertaining to road and pedestrian safety. PMID:23241696

  15. Pedestrian injury mitigation by autonomous braking.

    PubMed

    Rosén, Erik; Källhammer, Jan-Erik; Eriksson, Dick; Nentwich, Matthias; Fredriksson, Rikard; Smith, Kip

    2010-11-01

    The objective of this study was to calculate the potential effectiveness of a pedestrian injury mitigation system that autonomously brakes the car prior to impact. The effectiveness was measured by the reduction of fatally and severely injured pedestrians. The database from the German In-Depth Accident Study (GIDAS) was queried for pedestrians hit by the front of cars from 1999 to 2007. Case by case information on vehicle and pedestrian velocities and trajectories were analysed to estimate the field of view needed for a vehicle-based sensor to detect the pedestrians one second prior to the crash. The pre-impact braking system was assumed to activate the brakes one second prior to crash and to provide a braking deceleration up to the limit of the road surface conditions, but never to exceed 0.6 g. New impact speeds were then calculated for pedestrians that would have been detected by the sensor. These calculations assumed that all pedestrians who were within a given field of view but not obstructed by surrounding objects would be detected. The changes in fatality and severe injury risks were quantified using risk curves derived by logistic regression of the accident data. Summing the risks for all pedestrians, relationships between mitigation effectiveness, sensor field of view, braking initiation time, and deceleration were established. The study documents that the effectiveness at reducing fatally (severely) injured pedestrians in frontal collisions with cars reached 40% (27%) at a field of view of 40 degrees. Increasing the field of view further led to only marginal improvements in effectiveness. PMID:20728647

  16. Signaling system for multiple-access laser communications and interference protection.

    PubMed

    Riza, N A; Hershey, J E; Hassan, A A

    1993-04-10

    Signaling by spatial coding is proposed for asynchronous multiple-access free-space optical communications and interference mitigation. The large spatial bandwidth (e.g., 10(6) pixels) of each laser transmitter aperture is utilized for user coding, while the transmitter temporal bandwidth is preserved for information signals. Signal recovery is based on incoherent optical detection, spatial sampling, and electronic or optical matched filtering of the remotely received transmit optical beam Fresnel or Fraunhofer diffraction pattern. The proposed signaling method is appropriate for multiple-access free-space laser links involving multiple transmitters that use a common receiver. With electronic filtering, low-to-medium (e.g., 3 Mbits/s) data-rate users are appropriate. With a lenslet-array-based incoherent optical correlator, higher (e.g., 100 Mbits/s) data rates can be achieved. Improved interference protection is achieved cby spatially distributed bit-duration-based processing. Preliminary simulation results are carried out to demonstrate operating principles. PMID:20820331

  17. An on-board pedestrian detection and warning system with features of side pedestrian

    NASA Astrophysics Data System (ADS)

    Cheng, Ruzhong; Zhao, Yong; Wong, ChupChung; Chan, KwokPo; Xu, Jiayao; Wang, Xin'an

    2012-01-01

    Automotive Active Safety(AAS) is the main branch of intelligence automobile study and pedestrian detection is the key problem of AAS, because it is related with the casualties of most vehicle accidents. For on-board pedestrian detection algorithms, the main problem is to balance efficiency and accuracy to make the on-board system available in real scenes, so an on-board pedestrian detection and warning system with the algorithm considered the features of side pedestrian is proposed. The system includes two modules, pedestrian detecting and warning module. Haar feature and a cascade of stage classifiers trained by Adaboost are first applied, and then HOG feature and SVM classifier are used to refine false positives. To make these time-consuming algorithms available in real-time use, a divide-window method together with operator context scanning(OCS) method are applied to increase efficiency. To merge the velocity information of the automotive, the distance of the detected pedestrian is also obtained, so the system could judge if there is a potential danger for the pedestrian in the front. With a new dataset captured in urban environment with side pedestrians on zebra, the embedded system and its algorithm perform an on-board available result on side pedestrian detection.

  18. Necessity of guides in pedestrian emergency evacuation

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoxia; Dong, Hairong; Yao, Xiuming; Sun, Xubin; Wang, Qianling; Zhou, Min

    2016-01-01

    The role of guide who is in charge of leading pedestrians to evacuate in the case of emergency plays a critical role for the uninformed people. This paper first investigates the influence of mass behavior on evacuation dynamics and mainly focuses on the guided evacuation dynamics. In the extended crowd model proposed in this paper, individualistic behavior, herding behavior and environment influence are all considered for pedestrians who are not informed by the guide. According to the simulation results, herding behavior makes more pedestrians evacuate from the room in the same period of time. Besides, guided crowd demonstrates the same behavior of group dynamics which is characterized by gathering, conflicts and balance. Moreover, simulation results indicate guides with appropriate initial positions and quantity are more conducive to evacuation under a moderate initial density of pedestrians.

  19. TCRβ Feedback Signals Inhibit the Coupling of Recombinationally Accessible Vβ14 Segments with DJβ Complexes

    PubMed Central

    Yang-Iott, Katherine S.; Carpenter, Andrea C.; Rowh, Marta A. W.; Steinel, Natalie; Brady, Brenna L.; Hochedlinger, Konrad; Jaenisch, Rudolf; Bassing, Craig H.

    2010-01-01

    Antigen receptor allelic exclusion is thought to occur through mono-allelic initiation and subsequent feedback inhibition of recombinational accessibility. However, our previous analysis of mice containing a V(D)J recombination reporter inserted into Vβ14 (Vβ14Rep) indicated that Vβ14 chromatin accessibility is bi-allelic. To determine whether Vβ14 recombinational accessibility is subject to feedback inhibition, we analyzed TCRβ rearrangements in Vβ14Rep mice containing a pre-assembled in frame transgenic Vβ8.2Dβ1Jβ1.1 or an endogenous Vβ14Dβ1Jβ1.4 rearrangement on the homologous chromosome. Expression of either pre-assembled VβDJβCβ chain accelerated thymocyte development due to enhanced cellular selection, demonstrating that the rate-limiting step in early αβ T cell development is the assembly of an in-frame VβDJβ rearrangement. Expression of these pre-assembled VβDJβ rearrangements inhibited endogenous Vβ14-to-DJβ rearrangements as expected. However, in contrast to results predicted by the accepted model of TCRβ feedback inhibition, we found that expression of these pre-assembled TCRβ chains did not down-regulate recombinational accessibility of Vβ14 chromatin. Our findings suggest that TCRβ mediated feedback inhibition of Vβ14 rearrangements depends upon inherent properties of Vβ14, Dβ, and Jβ recombination signal sequences. PMID:20042591

  20. Performance of Multiple Pulse Multiple Delay Modulated UWB Signals in a Multiple Access Indoor Wireless Channel

    SciTech Connect

    Nekoogar, F

    2003-06-12

    In this paper, the performance of a two user UWB multiple access (UWB-MA) system based on multiple-pulse multiple-delay (MPMD) modulation scheme in an indoor wireless channel is evaluated by computer simulations. The indoor multipath propagation channel model used in this study is based on the modified statistical Saleh-Valenzuela model proposed by Foerester and Li from Intel. The simulation results indicate that the multipath performance of MPMD modulated signals in a multiple access system outperforms the nonmultipath case as the number of autocorrelation function (ACF) sampling points increases for each user. This is an unusual but important result, since MPMD receiver exploits multipath phenomenon in indoor wireless channels to increase the BER performance, hence the transmission rate in a UWB-MA system.

  1. Visual input signaling threat gains preferential access to awareness in a breaking continuous flash suppression paradigm.

    PubMed

    Gayet, Surya; Paffen, Chris L E; Belopolsky, Artem V; Theeuwes, Jan; Van der Stigchel, Stefan

    2016-04-01

    Visual input that signals threat is inherently relevant for survival. Accordingly, it has been demonstrated that threatening visual input elicits faster behavioral responses than non-threatening visual input. Considering that awareness is a prerequisite for performing demanding tasks and guiding novel behavior, we hypothesized that threatening visual input would gain faster access to awareness than non-threatening visual input. In the present study, we associated one of two basic visual stimuli, that were devoid of intrinsic relevance (colored annuli), with aversive stimulation (i.e., electric shocks) following a classical fear conditioning procedure. In the subsequent test phase no more electric shocks were delivered, and a breaking continuous flash suppression task was used to measure how fast these stimuli would access awareness. The results reveal that stimuli that were previously paired with an electric shock break through suppression faster than comparable stimuli that were not paired with an electric shock. PMID:26807500

  2. Towards an integrated approach of pedestrian behaviour and exposure.

    PubMed

    Papadimitriou, Eleonora

    2016-07-01

    In this paper, an integrated methodology for the analysis of pedestrian behaviour and exposure is proposed, allowing to identify and quantify the effect of pedestrian behaviour, road and traffic characteristics on pedestrian risk exposure, for each pedestrian and for populations of pedestrians. The paper builds on existing research on pedestrian exposure, namely the Routledge microscopic indicator, proposes adjustments to take into account road, traffic and human factors and extends the use of this indicator on area-wide level. Moreover, this paper uses integrated choice and latent variables (ICLV) models of pedestrian behaviour, taking into account road, traffic and human factors. Finally, a methodology is proposed for the integrated estimation of pedestrian behaviour and exposure on the basis of road, traffic and human factors. The method is tested with data from a field survey in Athens, Greece, which used pedestrian behaviour observations as well as a questionnaire on human factors of pedestrian behaviour. The data were used (i) to develop ICLV models of pedestrian behaviour and (ii) to estimate the behaviour and exposure of pedestrians for different road, traffic and behavioural scenarios. The results suggest that both pedestrian behaviour and exposure are largely defined by a small number of factors: road type, traffic volume and pedestrian risk-taking. The probability for risk-taking behaviour and the related exposure decrease in less demanding road and traffic environments. A synthesis of the results allows to enhance the understanding of the interactions between behaviour and exposure of pedestrians and to identify conditions of increased risk exposure. These conditions include principal urban arterials (where risk-taking behaviour is low but the related exposure is very high) and minor arterials (where risk-taking behaviour is more frequent, and the related exposure is still high). A "paradox" of increased risk-taking behaviour of pedestrians with low

  3. A study to investigate the walking speed of elderly adults with relation to pedestrian crossings.

    PubMed

    Bollard, Eva; Fleming, Hamish

    2013-02-01

    Elderly pedestrians are particularly at risk on the roads. The objective of this study was to investigate the walking speed of elderly adults and determine if it allows the safe clearance of pedestrian crossings. The increasing elderly population and high fatality rates of this age group on Irish roads necessitate this investigation. Fifty-two community-dwelling adults over the age of 65 years completed a 10-meter walk test. Acceleration and steady-state walking speed were accounted for. Twenty traffic-light-controlled pedestrian crossings were analyzed within a 1 kilometer radius of 4 day care centers in Kilkenny, Ireland. Values were recorded for the distance of the crossings and time of the light signals. The mean acceleration of the 52 participants was 0.20 ± 0.15 ms(-2) (mean ± SD) and the mean steady-state walking speed was 0.82 ± 0.27 ms(-1). In total, 30% of the pedestrian crossings investigated would not have permitted this sample of participants enough time to safely cross the road given the time of the green and amber light signals. Over 96% of participants would have been unable to cross a road of average distance on the amber signal alone. A substantial number of elderly adults walked slower than the speed required to safely cross the road. PMID:22844989

  4. Pedestrian detection by multispectral fusion

    NASA Astrophysics Data System (ADS)

    Ma, Yunqian; Wang, Zheng; Bazakos, Mike

    2006-04-01

    Security systems increasingly rely on the use of Automated Video Surveillance (AVS) technology. In particular the use of digital video renders itself to internet and local communications, remote monitoring, and to computer processing. AVS systems can perform many tedious and repetitive tasks currently performed by trained security personnel. AVS technology has already made some significant steps towards automating some basic security functions such as: motion detection, object tracking and event-based video recording. However, there are still many problems associated with just these automated functions, which need to be addressed further. Some examples of these problems are: the high "false alarm rate" and the "loss of track" under total or partial occlusion, when used under a wide range of operational parameters (day, night, sunshine, cloudy, foggy, range, viewing angle, clutter, etc.). Current surveillance systems work well only under a narrow range of operational parameters. Therefore, they need be hardened against a wide range of operational conditions. In this paper, we present a Multi-spectral fusion approach to perform accurate pedestrian segmentation under varying operational parameters. Our fusion method combines the "best" detection results from the visible images and the "best" from the thermal images. Commonly, the motion detection results in the visible images are easily affected by noise and shadows. The objects in the thermal image are relatively stable, but they may be missing some parts of the objects, because they thermally blend with the background. Our method makes use of the "best" object components and de-emphasize the "not best".

  5. Highway Safety Program Manual: Volume 14: Pedestrian Safety.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    Volume 14 of the 19-volume Highway Safety Program Manual (which provides guidance to State and local governments on preferred highway safety practices) concentrates on pedestrian safety. The purpose and objectives of a pedestrian safety program are outlined. Federal authority in the area of pedestrian safety and policies regarding a safety program…

  6. 14 CFR 139.329 - Pedestrians and ground vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Pedestrians and ground vehicles. 139.329... OF AIRPORTS Operations § 139.329 Pedestrians and ground vehicles. In a manner authorized by the... pedestrians and ground vehicles necessary for airport operations; (b) Establish and implement procedures...

  7. 14 CFR 139.329 - Pedestrians and ground vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Pedestrians and ground vehicles. 139.329... OF AIRPORTS Operations § 139.329 Pedestrians and ground vehicles. In a manner authorized by the... pedestrians and ground vehicles necessary for airport operations; (b) Establish and implement procedures...

  8. 14 CFR 139.329 - Pedestrians and ground vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Pedestrians and ground vehicles. 139.329... OF AIRPORTS Operations § 139.329 Pedestrians and ground vehicles. In a manner authorized by the... pedestrians and ground vehicles necessary for airport operations; (b) Establish and implement procedures...

  9. 14 CFR 139.329 - Pedestrians and ground vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pedestrians and ground vehicles. 139.329... OF AIRPORTS Operations § 139.329 Pedestrians and ground vehicles. In a manner authorized by the... pedestrians and ground vehicles necessary for airport operations; (b) Establish and implement procedures...

  10. 14 CFR 139.329 - Pedestrians and ground vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Pedestrians and ground vehicles. 139.329... OF AIRPORTS Operations § 139.329 Pedestrians and ground vehicles. In a manner authorized by the... pedestrians and ground vehicles necessary for airport operations; (b) Establish and implement procedures...

  11. Modeling the lateral pedestrian force on a rigid floor by a self-sustained oscillator

    NASA Astrophysics Data System (ADS)

    Erlicher, Silvano; Trovato, Andrea; Argoul, Pierre

    2010-07-01

    The main goal of this paper is the definition of a nonlinear single-degree-of-freedom oscillator able to accurately predict the lateral walking force of a pedestrian. The force exerted on the floor corresponds to its restoring force. The rigid floor case is analyzed, leading to an autonomous oscillator. Even though such an oscillator is a simplified representation of the human body, it should be able to reproduce two experimentally observed phenomena: (i) the time-history of lateral force is an approximately periodic signal; (ii) the walking motion is self-sustained, in the sense that the pedestrian/oscillator produces by itself the energy needed to sustain its motion. This implies that such an oscillator must be self-sustained. In addition, the self-sustained character entails that the autonomous oscillation has a natural amplitude and frequency, representing the natural walking amplitude and frequency of the pedestrian. An original model is proposed by modifying the so-called hybrid Van der Pol/Rayleigh oscillator, already used for applications in the field of robotics. A dynamic analysis of this oscillator is then performed through an energetic approach and a perturbation technique in order to get the stable limit cycle. The model parameters are finally identified from the experimental force signals, resulting from a test campaign on a population of 12 pedestrians: the agreement between model and experimental results is very good.

  12. Universal Power Law Governing Pedestrian Interactions

    NASA Astrophysics Data System (ADS)

    Karamouzas, Ioannis; Skinner, Brian; Guy, Stephen J.

    2014-12-01

    Human crowds often bear a striking resemblance to interacting particle systems, and this has prompted many researchers to describe pedestrian dynamics in terms of interaction forces and potential energies. The correct quantitative form of this interaction, however, has remained an open question. Here, we introduce a novel statistical-mechanical approach to directly measure the interaction energy between pedestrians. This analysis, when applied to a large collection of human motion data, reveals a simple power-law interaction that is based not on the physical separation between pedestrians but on their projected time to a potential future collision, and is therefore fundamentally anticipatory in nature. Remarkably, this simple law is able to describe human interactions across a wide variety of situations, speeds, and densities. We further show, through simulations, that the interaction law we identify is sufficient to reproduce many known crowd phenomena.

  13. Panic evacuation of single pedestrians and couples

    NASA Astrophysics Data System (ADS)

    Frank, G. A.; Dorso, C. O.

    2016-02-01

    Understanding the timing requirements for evacuation of people has focused primarily on independent pedestrians rather than pedestrians emotionally connected. However, the main statistical effects observed in crowds, the so-called “faster is slower”, “clever is not always better” and the “low visibility enhancement”, cannot explain the overall behavior of a crowd during an evacuation process when correlated pedestrians due to, for example feelings, are present. Our research addresses this issue and examines the statistical behavior of a mixture of individuals and couples during a (panic) escaping process. We found that the attractive feeling among couples plays an important role in the time delays during the evacuation of a single exit room.

  14. Establishing an injury prevention program to address pediatric pedestrian collisions.

    PubMed

    Violano, Pina; Davis, Kimberly A; Lane, Vivian; Lofthouse, Rebecca; Carusone, Carla

    2009-01-01

    The implementation of a pedestrian safety education program in public schools can change the knowledge and beliefs about safe pedestrian behaviors among students and their parents or caregivers with the goal of reducing morbidity and mortality of children. WalkSafe is a well-established, multiphase pedestrian safety intervention program. This program has been shown to improve pedestrian safety knowledge of school-aged children in kindergarten through grade 5 after receiving a 3-day educational curriculum. A reduction in pediatric pedestrian struck injuries is anticipated following program implementation in an urban area with significantly increased incidence of such injuries. PMID:20029287

  15. General Operational Procedure for Pedestrian Radiation Portal Monitors

    SciTech Connect

    Belooussov, Andrei V.

    2012-08-08

    This document outlines the basic conduct of operation (CONOPS) for a pedestrian radiation portal monitor (RPM), provided that the CONOPS is not facility or RPM specific and that it is based on a general understanding of a pedestrian RPM operation. The described CONOPS for a pedestrian RPM is defined by: (1) RPM design and operational characteristics, (2) type of pedestrian traffic, and (3) goal for RPM installation. Pedestrian RPMs normally are deployed for the continuous monitoring of individuals passing through point of control to detect the unauthorized traffic of radioactive/nuclear materials. RPMs generally are designed to detect gamma- and neutron-emitting materials.

  16. Road risk-perception and pedestrian injuries among students at Ain Shams University, Cairo, Egypt

    PubMed Central

    Ibrahim, Jehan M.; Day, Hannah; Hirshon, Jon Mark; El-Setouhy, Maged

    2012-01-01

    with modification of the traffic environment (such as provision of crossing signals) might be effective in preventing the occurrence of pedestrian injury. PMID:21502783

  17. A Pedestrian Detection Scheme Using a Coherent Phase Difference Method Based on 2D Range-Doppler FMCW Radar

    PubMed Central

    Hyun, Eugin; Jin, Young-Seok; Lee, Jong-Hun

    2016-01-01

    For an automotive pedestrian detection radar system, fast-ramp based 2D range-Doppler Frequency Modulated Continuous Wave (FMCW) radar is effective for distinguishing between moving targets and unwanted clutter. However, when a weak moving target such as a pedestrian exists together with strong clutter, the pedestrian may be masked by the side-lobe of the clutter even though they are notably separated in the Doppler dimension. To prevent this problem, one popular solution is the use of a windowing scheme with a weighting function. However, this method leads to a spread spectrum, so the pedestrian with weak signal power and slow Doppler may also be masked by the main-lobe of clutter. With a fast-ramp based FMCW radar, if the target is moving, the complex spectrum of the range- Fast Fourier Transform (FFT) is changed with a constant phase difference over ramps. In contrast, the clutter exhibits constant phase irrespective of the ramps. Based on this fact, in this paper we propose a pedestrian detection for highly cluttered environments using a coherent phase difference method. By detecting the coherent phase difference from the complex spectrum of the range-FFT, we first extract the range profile of the moving pedestrians. Then, through the Doppler FFT, we obtain the 2D range-Doppler map for only the pedestrian. To test the proposed detection scheme, we have developed a real-time data logging system with a 24 GHz FMCW transceiver. In laboratory tests, we verified that the signal processing results from the proposed method were much better than those expected from the conventional 2D FFT-based detection method. PMID:26805835

  18. A Pedestrian Detection Scheme Using a Coherent Phase Difference Method Based on 2D Range-Doppler FMCW Radar.

    PubMed

    Hyun, Eugin; Jin, Young-Seok; Lee, Jong-Hun

    2016-01-01

    For an automotive pedestrian detection radar system, fast-ramp based 2D range-Doppler Frequency Modulated Continuous Wave (FMCW) radar is effective for distinguishing between moving targets and unwanted clutter. However, when a weak moving target such as a pedestrian exists together with strong clutter, the pedestrian may be masked by the side-lobe of the clutter even though they are notably separated in the Doppler dimension. To prevent this problem, one popular solution is the use of a windowing scheme with a weighting function. However, this method leads to a spread spectrum, so the pedestrian with weak signal power and slow Doppler may also be masked by the main-lobe of clutter. With a fast-ramp based FMCW radar, if the target is moving, the complex spectrum of the range- Fast Fourier Transform (FFT) is changed with a constant phase difference over ramps. In contrast, the clutter exhibits constant phase irrespective of the ramps. Based on this fact, in this paper we propose a pedestrian detection for highly cluttered environments using a coherent phase difference method. By detecting the coherent phase difference from the complex spectrum of the range-FFT, we first extract the range profile of the moving pedestrians. Then, through the Doppler FFT, we obtain the 2D range-Doppler map for only the pedestrian. To test the proposed detection scheme, we have developed a real-time data logging system with a 24 GHz FMCW transceiver. In laboratory tests, we verified that the signal processing results from the proposed method were much better than those expected from the conventional 2D FFT-based detection method. PMID:26805835

  19. Simulator Study of Driver Responses to Pedestrian Treatments at Multilane Roundabouts

    PubMed Central

    Salamati, Katayoun; Schroeder, Bastian; Rouphail, Nagui M.; Cunningham, Christopher; Zhang, Yu; Kaber, David

    2013-01-01

    Previous studies have shown that roundabouts – especially multilane roundabouts - pose accessibility challenges to pedestrians with vision impairments, in part due to a lack of yielding by drivers, especially on multilane roundabout exit legs. In this study, three different treatments are assessed in terms of their propensity for increasing driver yielding rate using a driving simulator. These are stop bar and crosswalk relocation away from the beginning of exit leg, and two types of beacons, namely a Pedestrian Hybrid Beacon (PHB) and a Rectangular Rapid Flashing Beacon (RRFB). The study shows that installation of any kind of beacon (PHB or RRFB) with or without crosswalk relocation increases driver yielding rates significantly. Relocating the crosswalk does not provide a significant increase in driver yielding rate for the base case, but appeared to further enhance the effectiveness of the PHB and RRFB treatments. The results of using an eye tracker on drivers to track their gaze pattern while exiting the roundabout shows that having a beacon installed with crosswalk relocation increases drivers’ attention both on the beacon and the pedestrian along the road. However, a portion of participants failed to see and react to the pedestrian treatments, causing concern about the visibility of these treatments at the roundabout exit leg. PMID:24353370

  20. Validation of pedestrian throw equations by video footage of real life pedestrian/vehicle collisions.

    PubMed

    Cheng, Yuk-Ki; Wong, Koon-Hung; Tam, Cheok-Ning; Tam, Yiu-Yan; Wong, Tai-Wai; Tao, Chi-Hang

    2015-12-01

    A total of 11 real life vehicle/pedestrian collisions in 2012-2014 were captured by CCTV cameras/car cameras in Hong Kong. Some of the footage was recorded in HD format at 30 frames per second, enabling accurate determinations of impact speeds with pedestrians, exact points of impacts and final rest positions of pedestrians as well as kinematics of the collisions. The calculated impact speeds from footage analysis were used to validate the published empirical and semi-empirical pedestrian throw equations. The applicability of these equations to collisions on sloped carriageways was discussed. The presented results, including 6 forward projection trajectory cases, enrich the existing limited real life data from footage analysis for further validation of the published methodologies. PMID:26562788

  1. Effect of traffic information on the stability pedestrian flow*

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaomei; Xie, Dongfan; Li, Haiou

    Based on traffic information, an extended two-dimensional optimal velocity model is presented by incorporating velocity difference between two neighboring pedestrians. Linear stability conditions are obtained by theoretical analysis, and the results show that the traffic information can promote the stability of pedestrian flow. Furthermore, the model is applied to mixed pedestrian flow, where only part of pedestrians follows the information and others neglect it. It is found that the pedestrians complying with traffic guidance system (called TGS pedestrian) can make the mixed flow more stable, and some unstable regions can change to stable region when the proportion of TGS pedestrian is large enough. It is also found that the initial distribution of them has little effect on the flow.

  2. Motor Schema-Based Cellular Automaton Model for Pedestrian Dynamics

    NASA Astrophysics Data System (ADS)

    Weng, Wenguo; Hasemi, Yuji; Fan, Weicheng

    A new cellular automaton model for pedestrian dynamics based on motor schema is presented. Each pedestrian is treated as an intelligent mobile robot, and motor schemas including move-to-goal, avoid-away and avoid-around drive pedestrians to interact with their environment. We investigate the phenomenon of many pedestrians with different move velocities escaping from a room. The results show that the pedestrian with high velocity have predominance in competitive evacuation, if we only consider repulsion from or avoiding around other pedestrians, and interaction with each other leads to disordered evacuation, i.e., decreased evacuation efficiency. Extensions of the model using learning algorithms for controlling pedestrians, i.e., reinforcement learning, neural network and genetic algorithms, etc. are noted.

  3. An examination of the environmental attributes associated with pedestrian-vehicular crashes near public schools.

    PubMed

    Clifton, Kelly J; Kreamer-Fults, Kandice

    2007-07-01

    This paper examines pedestrian-vehicular crashes in the vicinity of public schools, the severity of injuries sustained, and their relationship to the physical and social attributes near the schools. Multivariate models of crash severity and crash risk exposure were estimated as a function of social and physical characteristics of the area immediately surrounding schools in Baltimore City, Maryland. Results show that the presence of a driveway or turning bay on the school entrance decreases both crash occurrence and injury severity. Conversely, the presence of recreational facilities on the school site is positively associated with crash occurrence and injury severity of crashes. Findings related to neighborhood characteristics were mixed but the significant variables - transit access, commercial access, and population density - are generally associated with increased pedestrian demand and should be interpreted with care. The results of this study are relevant for Safe Routes to School projects and point to areas meriting further study. PMID:17174259

  4. Why more male pedestrians die in vehicle-pedestrian collisions than females: a decompositional analysis

    PubMed Central

    Zhu, Motao; Zhao, Songzhu; Coben, Jeffrey H.; Smith, Gordon S.

    2013-01-01

    Objective Pedestrians account for a third of the 1.2 million traffic fatalities annually worldwide, and males are overrepresented. We examined the factors that contribute to this male-female discrepancy: walking exposure (kilometers walked per person-year), vehicle-pedestrian collision risk (number of collisions per kilometers walked), and vehicle-pedestrian collision case fatality rate (number of deaths per collision). Design The decomposition method quantifies the relative contributions of individual factors to death rate ratios among groups. The male-female ratio of pedestrian death rates can be expressed as the product of three component ratios: walking exposure, collision risk, and case fatality rate. Data sources included the 2008–2009 U.S. Fatality Analysis Reporting System, General Estimates System, National Household Travel Survey, and population estimates. Setting U.S. Participants Pedestrians age 5 and older. Main outcome measures death rate per person-year, kilometers walked per person-year, collisions per kilometers walked, and deaths per collision by sex. Results The pedestrian death rate per person-year for males was 2.3 times that for females. This ratio of male to female rates can be expressed as the product of three component ratios: 0.995 for walking exposure, 1.191 for collision risk, and 1.976 for case fatality rate. The relative contributions of these components were 1%, 20% and 79%, respectively. Conclusions The majority of the male-female discrepancy in 2008–2009 pedestrian deaths in the U.S. is attributed to a higher fatality per collision rate among male pedestrians. PMID:23197672

  5. Research of Pedestrian Crossing Safety Facilities Based on the Video Detection

    NASA Astrophysics Data System (ADS)

    Li, Sheng-Zhen; Xie, Quan-Long; Zang, Xiao-Dong; Tang, Guo-Jun

    Since that the pedestrian crossing facilities at present is not perfect, pedestrian crossing is in chaos and pedestrians from opposite direction conflict and congest with each other, which severely affects the pedestrian traffic efficiency, obstructs the vehicle and bringing about some potential security problems. To solve these problems, based on video identification, a pedestrian crossing guidance system was researched and designed. It uses the camera to monitor the pedestrians in real time and sums up the number of pedestrians through video detection program, and a group of pedestrian's induction lamp array is installed at the interval of crosswalk, which adjusts color display according to the proportion of pedestrians from both sides to guide pedestrians from both opposite directions processing separately. The emulation analysis result from cellular automaton shows that the system reduces the pedestrian crossing conflict, shortens the time of pedestrian crossing and improves the safety of pedestrians crossing.

  6. [Risk of accidents for a Parisian pedestrian].

    PubMed

    Vayre, P

    2001-12-01

    The risk of accident for a parisian pedestrian is of reduced frequency and of moderate severity (terrorism and natural disasters not included) according to the statistics of 1999. This is due to security measures and the excellent organisation of assistance to wounded persons. The improvement in protection of pedestrians, even the disabled and elderly persons will soon make Paris the best protected megalopolis of our continent. Pedestrians are involved in 28% of accidents on public streets with a mortality of 1.2%, with serious injuries in 12.6% of the cases. Injuries without collision occur in 57% of the cases. 18% of the wounded older than 75 years with 1.8% of deaths and 66% of severe injury. Accidents related to public transportation represent a very slight risk of 0.00044%. By modification of the concept of transportation and its materials over a five year period there is a decrease in the number of the victims (-3.75%), in spite of the increase of accidents (3.5%). For lone pedestrian being victims of aggression in public places, after a decrease of 10% in 1999, there is in 2001 an increase which raises the question of police proximity again. Over a five year period the RATP (subway authority) has noticed a 14.77% decrease of thefts and a 54.78% decrease in attacks... This makes the Parisian railnet (subway mostly) seven times less dangerous than the streets. PMID:11803819

  7. The Pedestrian Behaviour of Spanish Adolescents

    ERIC Educational Resources Information Center

    Sullman, M. J. M.; Gras, M. E.; Font-Mayolas, S.; Masferrer, L.; Cunill, M.; Planes, M.

    2011-01-01

    Adolescent pedestrians are a particularly vulnerable group of road users. This research tested the applicability of the recently developed Adolescent Road user Behaviour Questionnaire (ARBQ) amongst a sample of 2006 Spanish adolescents. Confirmatory Factor Analysis of the full scale found that the original three factors did not adequately fit the…

  8. Safety impacts of platform tram stops on pedestrians in mixed traffic operation: A comparison group before-after crash study.

    PubMed

    Naznin, Farhana; Currie, Graham; Logan, David; Sarvi, Majid

    2016-01-01

    Tram stops in mixed traffic environments present a variety of safety, accessibility and transport efficiency challenges. In Melbourne, Australia the hundred year-old electric tram system is progressively being modernized to improve passenger accessibility. Platform stops, incorporating raised platforms for level entry into low floor trams, are being retro-fitted system-wide to replace older design stops. The aim of this study was to investigate the safety impacts of platform stops over older design stops (i.e. Melbourne safety zone tram stops) on pedestrians in the context of mixed traffic tram operation in Melbourne, using an advanced before-after crash analysis approach, the comparison group (CG) method. The CG method evaluates safety impacts by taking into account the general trends in safety and the unobserved factors at treatment and comparison sites that can alter the outcomes of a simple before-after analysis. The results showed that pedestrian-involved all injury crashes reduced by 43% after platform stop installation. This paper also explores a concern that the conventional CG method might underestimate safety impacts as a result of large differences in passenger stop use between treatment and comparison sites, suggesting differences in crash risk exposure. To adjust for this, a modified analysis explored crash rates (crash counts per 10,000 stop passengers) for each site. The adjusted results suggested greater reductions in pedestrian-involved crashes after platform stop installation: an 81% reduction in pedestrian-involved all injury crashes and 86% reduction in pedestrian-involved FSI crashes, both are significant at the 95% level. Overall, the results suggest that platform stops have considerable safety benefits for pedestrians. Implications for policy and areas for future research are explored. PMID:26476596

  9. Correlation Between Euro NCAP Pedestrian Test Results and Injury Severity in Injury Crashes with Pedestrians and Bicyclists in Sweden.

    PubMed

    Strandroth, Johan; Sternlund, Simon; Lie, Anders; Tingvall, Claes; Rizzi, Matteo; Kullgren, Anders; Ohlin, Maria; Fredriksson, Rikard

    2014-11-01

    Pedestrians and bicyclists account for a significant share of deaths and serious injuries in the road transport system. The protection of pedestrians in car-to-pedestrian crashes has therefore been addressed by friendlier car fronts and since 1997, the European New Car Assessment Program (Euro NCAP) has assessed the level of protection for most car models available in Europe. In the current study, Euro NCAP pedestrian scoring was compared with real-life injury outcomes in car-to-pedestrian and car-tobicyclist crashes occurring in Sweden. Approximately 1200 injured pedestrians and 2000 injured bicyclists were included in the study. Groups of cars with low, medium and high pedestrian scores were compared with respect to pedestrian injury severity on the Maximum Abbreviated Injury Scale (MAIS)-level and risk of permanent medical impairment (RPMI). Significant injury reductions to both pedestrians and bicyclists were found between low and high performing cars. For pedestrians, the reduction of MAIS2+, MAIS3+, RPMI1+ and RPMI10+ ranged from 20-56% and was significant on all levels except for MAIS3+ injuries. Pedestrian head injuries had the highest reduction, 80-90% depending on level of medical impairment. For bicyclist, an injury reduction was only observed between medium and high performing cars. Significant injury reductions were found for all body regions. It was also found that cars fitted with autonomous emergency braking including pedestrian detection might have a 60-70% lower crash involvement than expected. Based on these results, it was recommended that pedestrian protection are implemented on a global scale to provide protection for vulnerable road users worldwide. PMID:26192956

  10. Traffic signal design and simulation for vulnerable road users safety and bus preemption

    NASA Astrophysics Data System (ADS)

    Lo, Shih-Ching; Huang, Hsieh-Chu

    2015-01-01

    Mostly, pedestrian car accidents occurred at a signalized interaction is because pedestrians cannot across the intersection safely within the green light. From the viewpoint of pedestrian, there might have two reasons. The first one is pedestrians cannot speed up to across the intersection, such as the elders. The other reason is pedestrians do not sense that the signal phase is going to change and their right-of-way is going to be lost. Developing signal logic to protect pedestrian, who is crossing an intersection is the first purpose of this study. In addition, to improve the reliability and reduce delay of public transportation service is the second purpose. Therefore, bus preemption is also considered in the designed signal logic. In this study, the traffic data of the intersection of Chong-Qing North Road and Min-Zu West Road, Taipei, Taiwan, is employed to calibrate and validate the signal logic by simulation. VISSIM 5.20, which is a microscopic traffic simulation software, is employed to simulate the signal logic. From the simulated results, the signal logic presented in this study can protect pedestrians crossing the intersection successfully. The design of bus preemption can reduce the average delay. However, the pedestrian safety and bus preemption signal will influence the average delay of cars largely. Thus, whether applying the pedestrian safety and bus preemption signal logic to an intersection or not should be evaluated carefully.

  11. Traffic signal design and simulation for vulnerable road users safety and bus preemption

    SciTech Connect

    Lo, Shih-Ching; Huang, Hsieh-Chu

    2015-01-22

    Mostly, pedestrian car accidents occurred at a signalized interaction is because pedestrians cannot across the intersection safely within the green light. From the viewpoint of pedestrian, there might have two reasons. The first one is pedestrians cannot speed up to across the intersection, such as the elders. The other reason is pedestrians do not sense that the signal phase is going to change and their right-of-way is going to be lost. Developing signal logic to protect pedestrian, who is crossing an intersection is the first purpose of this study. In addition, to improve the reliability and reduce delay of public transportation service is the second purpose. Therefore, bus preemption is also considered in the designed signal logic. In this study, the traffic data of the intersection of Chong-Qing North Road and Min-Zu West Road, Taipei, Taiwan, is employed to calibrate and validate the signal logic by simulation. VISSIM 5.20, which is a microscopic traffic simulation software, is employed to simulate the signal logic. From the simulated results, the signal logic presented in this study can protect pedestrians crossing the intersection successfully. The design of bus preemption can reduce the average delay. However, the pedestrian safety and bus preemption signal will influence the average delay of cars largely. Thus, whether applying the pedestrian safety and bus preemption signal logic to an intersection or not should be evaluated carefully.

  12. What you see isn't always what you get: Auditory word signals trump consciously perceived words in lexical access.

    PubMed

    Ostrand, Rachel; Blumstein, Sheila E; Ferreira, Victor S; Morgan, James L

    2016-06-01

    Human speech perception often includes both an auditory and visual component. A conflict in these signals can result in the McGurk illusion, in which the listener perceives a fusion of the two streams, implying that information from both has been integrated. We report two experiments investigating whether auditory-visual integration of speech occurs before or after lexical access, and whether the visual signal influences lexical access at all. Subjects were presented with McGurk or Congruent primes and performed a lexical decision task on related or unrelated targets. Although subjects perceived the McGurk illusion, McGurk and Congruent primes with matching real-word auditory signals equivalently primed targets that were semantically related to the auditory signal, but not targets related to the McGurk percept. We conclude that the time course of auditory-visual integration is dependent on the lexicality of the auditory and visual input signals, and that listeners can lexically access one word and yet consciously perceive another. PMID:27011021

  13. Asynchronous detection of optical code division multiple access signals using a bandwidth-efficient and wavelength-aware receiver.

    PubMed

    Fok, Mable P; Deng, Yanhua; Prucnal, Paul R

    2010-04-01

    We experimentally demonstrate what we believe to be a novel detection scheme for interfacing asynchronous optical code division multiple access (CDMA) signals with an electronic clock and data recovery system that operates only at the baseband bandwidth. This allows using a large optical bandwidth expansion factor in which the optical chip rate is much larger than the bandwidth of the optoelectronic receiver. The received optical CDMA signal is launched into a four-wave-mixing-based wavelength-aware all-optical front end that rejects multiaccess interference, followed by an amplitude-noise suppression stage comprised of a semiconductor optical amplifier. The clean signal is then converted into a non-return-to-zero-like signal by a baseband receiver. Using the proposed detection scheme, asynchronous transmission and detection of optical CDMA signals is implemented. With the novel detection scheme, the classic CDMA near-far problem is mitigated, and error-free detection is easily obtained. PMID:20364229

  14. Simulation of Pedestrian Dynamic Using a Vector Floor Field Model

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Hou, Zhongsheng; Zhan, Minghui

    2013-04-01

    Simulation of complex scenarios and multi-direction pedestrian flow is a main challenge to microscopic model of pedestrian movement. It is an issue to simulate real pedestrian traffic with great fidelity while keeping its computational cost at an acceptable level. This paper reports on an improved floor field model called vector floor field model to simulate pedestrian flows in some basic scenarios. In this model, vectorization of static floor field and dynamic floor field are used to indicate preference directions and the pedestrian flow tendency, respectively. Pedestrian transition depends on both their preference directions and tendency. The simulations in some basic scenarios are conducted, quantitative comparison to the record of practical experiments and standard floor field model is given as well, and the results indicate the effectivity of this model. An adjusted static vector floor field is also proposed to simulate pedestrian flow in turning scenario. The vector floor field model is also sufficient to simulate some essential features in pedestrian dynamic, such as lane formation. This model can be widely used in the simulation of multi-direction pedestrian at turning, crossing and other junctions.

  15. A Universal Power Law Governing Pedestrian Interactions

    NASA Astrophysics Data System (ADS)

    Karamouzas, Ioannis; Skinner, Brian; Guy, Stephen J.

    2015-03-01

    Human crowds often bear a striking resemblance to interacting particle systems, and this has prompted many researchers to describe pedestrian dynamics in terms of interaction forces and potential energies. The correct quantitative form of this interaction, however, has remained an open question. Here, we introduce a novel statistical-mechanical approach to directly measure the interaction energy between pedestrians. This analysis, when applied to a large collection of human motion data, reveals a simple power law interaction that is based not on the physical separation between pedestrians but on their projected time to a potential future collision, and is therefore fundamentally anticipatory in nature. Remarkably, this simple law is able to describe human interactions across a wide variety of situations, speeds and densities. We further show, through simulations, that the interaction law we identify is sufficient to reproduce many known crowd phenomena. Work at Argonne National Laboratory is supported by the U.S. Department of Energy, under Contract No. DE-AC02-06CH11357. Work at the University of Minnesota is supported by MnDRIVE Initiative on Robotics, Sensors, and Advanced Manufacturing.

  16. Dynamic feature analysis in bidirectional pedestrian flows

    NASA Astrophysics Data System (ADS)

    Xiao-Xia, Yang; Winnie, Daamen; Serge, Paul Hoogendoorn; Hai-Rong, Dong; Xiu-Ming, Yao

    2016-02-01

    Analysis of dynamic features of pedestrian flows is one of the most exciting topics in pedestrian dynamics. This paper focuses on the effect of homogeneity and heterogeneity in three parameters of the social force model, namely desired velocity, reaction time, and body size, on the moving dynamics of bidirectional pedestrian flows in the corridors. The speed and its deviation in free flows are investigated. Simulation results show that the homogeneous higher desired speed which is less than a critical threshold, shorter reaction time or smaller body size results in higher speed of flows. The free dynamics is more sensitive to the heterogeneity in desired speed than that in reaction time or in body size. In particular, an inner lane formation is observed in normal lanes. Furthermore, the breakdown probability and the start time of breakdown are focused on. This study reveals that the sizes of homogeneous desired speed, reaction time or body size play more important roles in affecting the breakdown than the heterogeneities in these three parameters do. Project supported jointly by the National Natural Science Foundation of China (Grant No. 61233001) and the Fundamental Research Funds for Central Universities of China (Grant No. 2013JBZ007).

  17. Modeling of pedestrian motion for recognition

    NASA Astrophysics Data System (ADS)

    Saisan, Payam; Medasani, Swarup; Srinivasa, Narayan; Owechko, Yuri

    2005-03-01

    Good pedestrian classifiers that analyze static images for presence of pedestrians are in existence. However, even a low false positive error rating is sufficient to flood a real system with false warnings. We address the problem of pedestrian motion (gait) modeling and recognition using sequences of images rather than static individual frames, thereby exploiting information in the dynamics. We use two different representations and corresponding distances for gait sequences. In the first a gait is represented as a manifold in a lower dimensional space corresponding to gait images. In the second a gait image sequence is represented as the output of a dynamical system whose underlying driving process is an action like walking or running. We examine distance functions corresponding to these representations. For dynamical systems we formulate distances derived based on parameters of the system taking into account both the structure of the output space and the dynamics within it. Given appearance based models we present results demonstrating the discriminative power of the proposed distances

  18. Pedestrian- and driver-related factors associated with the risk of causing collisions involving pedestrians in Spain.

    PubMed

    Jiménez-Mejías, Eladio; Martínez-Ruiz, Virginia; Amezcua-Prieto, Carmen; Olmedo-Requena, Rocío; Luna-Del-Castillo, Juan de Dios; Lardelli-Claret, Pablo

    2016-07-01

    This study aimed to quantify the association between pedestrian- and driver-related factors and the risk of causing road crashes involving pedestrians in urban areas in Spain between 1993 and 2011. From the nationwide police-based registry of road crashes with victims in Spain, we analyzed all 63,205 pairs of pedestrians and drivers involved in crashes in urban areas in which only the pedestrian or only the driver was at fault. Logistic regression models were used to obtain adjusted odds ratios to assess the strength of association between each individual-related variable and the pedestrian's odds of being at fault for the crash (and conversely, the driver's odds of not being at fault). The subgroups of road users at high risk of causing a road crash with a pedestrian in urban areas were young and male pedestrians, pedestrians with psychophysical conditions or health problems, the youngest and the oldest drivers, and drivers with markers of high-risk behaviors (alcohol use, nonuse of safety devices, and driving without a valid license). These subgroups should be targeted by preventive strategies intended to decrease the rate of urban road crashes involving pedestrians in Spain. PMID:27085592

  19. Towards 5G: A Photonic Based Millimeter Wave Signal Generation for Applying in 5G Access Fronthaul

    NASA Astrophysics Data System (ADS)

    Alavi, S. E.; Soltanian, M. R. K.; Amiri, I. S.; Khalily, M.; Supa'At, A. S. M.; Ahmad, H.

    2016-01-01

    5G communications require a multi Gb/s data transmission in its small cells. For this purpose millimeter wave (mm-wave) RF signals are the best solutions to be utilized for high speed data transmission. Generation of these high frequency RF signals is challenging in electrical domain therefore photonic generation of these signals is more studied. In this work, a photonic based simple and robust method for generating millimeter waves applicable in 5G access fronthaul is presented. Besides generating of the mm-wave signal in the 60 GHz frequency band the radio over fiber (RoF) system for transmission of orthogonal frequency division multiplexing (OFDM) with 5 GHz bandwidth is presented. For the purpose of wireless transmission for 5G application the required antenna is designed and developed. The total system performance in one small cell was studied and the error vector magnitude (EVM) of the system was evaluated.

  20. Towards 5G: A Photonic Based Millimeter Wave Signal Generation for Applying in 5G Access Fronthaul.

    PubMed

    Alavi, S E; Soltanian, M R K; Amiri, I S; Khalily, M; Supa'at, A S M; Ahmad, H

    2016-01-01

    5G communications require a multi Gb/s data transmission in its small cells. For this purpose millimeter wave (mm-wave) RF signals are the best solutions to be utilized for high speed data transmission. Generation of these high frequency RF signals is challenging in electrical domain therefore photonic generation of these signals is more studied. In this work, a photonic based simple and robust method for generating millimeter waves applicable in 5G access fronthaul is presented. Besides generating of the mm-wave signal in the 60 GHz frequency band the radio over fiber (RoF) system for transmission of orthogonal frequency division multiplexing (OFDM) with 5 GHz bandwidth is presented. For the purpose of wireless transmission for 5G application the required antenna is designed and developed. The total system performance in one small cell was studied and the error vector magnitude (EVM) of the system was evaluated. PMID:26814621

  1. Towards 5G: A Photonic Based Millimeter Wave Signal Generation for Applying in 5G Access Fronthaul

    PubMed Central

    Alavi, S. E.; Soltanian, M. R. K.; Amiri, I. S.; Khalily, M.; Supa’at, A. S. M.; Ahmad, H.

    2016-01-01

    5G communications require a multi Gb/s data transmission in its small cells. For this purpose millimeter wave (mm-wave) RF signals are the best solutions to be utilized for high speed data transmission. Generation of these high frequency RF signals is challenging in electrical domain therefore photonic generation of these signals is more studied. In this work, a photonic based simple and robust method for generating millimeter waves applicable in 5G access fronthaul is presented. Besides generating of the mm-wave signal in the 60 GHz frequency band the radio over fiber (RoF) system for transmission of orthogonal frequency division multiplexing (OFDM) with 5 GHz bandwidth is presented. For the purpose of wireless transmission for 5G application the required antenna is designed and developed. The total system performance in one small cell was studied and the error vector magnitude (EVM) of the system was evaluated. PMID:26814621

  2. Modeling pedestrian behaviors under attracting incidents using cellular automata

    NASA Astrophysics Data System (ADS)

    Chen, Yanyan; Chen, Ning; Wang, Yang; Wang, Zhenbao; Feng, Guochen

    2015-08-01

    Compared to vehicular flow, pedestrian flow is more complicated as it is free from the restriction of the lane and more flexible. Due to the lack of modeling pedestrian behaviors under attracting incidents (incidents which attract pedestrians around to gather), this paper proposes a new cellular automata model aiming to reproduce the behaviors induced by such attracting incidents. When attracting incidents occur, the proposed model will classify pedestrians around the incidents into three groups: the "unaffected" type, the "stopped" type and the "onlooking" type. The "unaffected" type represents the pedestrians who are not interested in the attracting incidents and its dynamics are the same as that under normal circumstances which are the main target in the previous works. The "stopped" type represents the pedestrians are somewhat interested in the attracting incidents, but unwilling to move close to the venues. Its dynamics are determined by "stopped" utility which can make the pedestrians stop for a while. The "onlooking" type represents the pedestrians who show strong interest in the attracting incidents and intend to move close to the venues to gain more information. The "onlooking" pedestrians will take a series of reactions to attracting incidents, such as approaching to the venues, stopping and watching the attracting incidents, leaving the venues, which have all been considered in the proposed model. The simulation results demonstrate that the proposed model can capture the macro-characteristics of pedestrian traffic flow under normal circumstances and possesses the fundamental characteristics of the pedestrian behaviors under attracting incidents around which a torus-shaped crowd is typically formed.

  3. 7 CFR 500.11 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Vehicular and pedestrian traffic. 500.11 Section 500... and pedestrian traffic. (a) Drivers of all vehicles in or on USNA property shall drive only on... and directions of the Security Staff and all posted traffic signs. (b) The blocking of...

  4. 7 CFR 502.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Vehicular and pedestrian traffic. 502.12 Section 502.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON BELTSVILLE AGRICULTURE RESEARCH CENTER PROPERTY, BELTSVILLE, MARYLAND § 502.12 Vehicular and pedestrian...

  5. 7 CFR 500.11 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Vehicular and pedestrian traffic. 500.11 Section 500... and pedestrian traffic. (a) Drivers of all vehicles in or on USNA property shall drive only on... and directions of the Security Staff and all posted traffic signs. (b) The blocking of...

  6. 7 CFR 500.11 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Vehicular and pedestrian traffic. 500.11 Section 500... and pedestrian traffic. (a) Drivers of all vehicles in or on USNA property shall drive only on... and directions of the Security Staff and all posted traffic signs. (b) The blocking of...

  7. 7 CFR 500.11 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Vehicular and pedestrian traffic. 500.11 Section 500.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE NATIONAL ARBORETUM Conduct on U.S. National Arboreturm Property § 500.11 Vehicular and pedestrian traffic. (a) Drivers...

  8. 7 CFR 500.11 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Vehicular and pedestrian traffic. 500.11 Section 500... and pedestrian traffic. (a) Drivers of all vehicles in or on USNA property shall drive only on... and directions of the Security Staff and all posted traffic signs. (b) The blocking of...

  9. 7 CFR 502.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Vehicular and pedestrian traffic. 502.12 Section 502... § 502.12 Vehicular and pedestrian traffic. (a) Drivers of all vehicles whether or not motorized in or on... and directions of the security staff and all posted traffic signs; (b) The blocking of...

  10. 7 CFR 502.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Vehicular and pedestrian traffic. 502.12 Section 502... § 502.12 Vehicular and pedestrian traffic. (a) Drivers of all vehicles whether or not motorized in or on... and directions of the security staff and all posted traffic signs; (b) The blocking of...

  11. 7 CFR 502.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Vehicular and pedestrian traffic. 502.12 Section 502... § 502.12 Vehicular and pedestrian traffic. (a) Drivers of all vehicles whether or not motorized in or on... and directions of the security staff and all posted traffic signs; (b) The blocking of...

  12. Primary Grade Teachers' Perceptions and Practices regarding Pedestrian Safety Education

    ERIC Educational Resources Information Center

    Lartey, Grace K.; Price, James H.; Telljohann, Susan K.; Dake, Joseph A.; Yingling, Faith

    2007-01-01

    Background: Pedestrian injury is the third leading cause of unintentional injury and death among children 1-14 years old. The purpose of this study was to examine primary grade teachers' perceived role in pedestrian safety education. Methods: A total of 630 surveys were sent to a national random sample of primary school teachers and 54% responded.…

  13. Pedestrian Safety--A Step in the Right Direction.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of General Education Curriculum Development.

    This guide contains interdisciplinary teaching materials to help administrators and teachers develop pedestrian safety programs. The materials can be easily integrated with language arts, art, and social studies courses. Objectives of the materials, which can be used in kindergarten through grade nine, include understanding pedestrians' rights and…

  14. 32 CFR 636.26 - Pedestrian's rights and duties.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort Stewart, Georgia § 636.26 Pedestrian's rights and duties. (a) Pedestrians will obey all traffic control devices and regulations, unless directed to do otherwise by the Military Police. (b) When...

  15. 32 CFR 636.26 - Pedestrian's rights and duties.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort Stewart, Georgia § 636.26 Pedestrian's rights and duties. (a) Pedestrians will obey all traffic control devices and regulations, unless directed to do otherwise by the Military Police. (b) When...

  16. Effect of speed matching on fundamental diagram of pedestrian flow

    NASA Astrophysics Data System (ADS)

    Fu, Zhijian; Luo, Lin; Yang, Yue; Zhuang, Yifan; Zhang, Peitong; Yang, Lizhong; Yang, Hongtai; Ma, Jian; Zhu, Kongjin; Li, Yanlai

    2016-09-01

    Properties of pedestrian may change along their moving path, for example, as a result of fatigue or injury, which has never been properly investigated in the past research. The paper attempts to study the speed matching effect (a pedestrian adjusts his velocity constantly to the average velocity of his neighbors) and its influence on the density-velocity relationship (a pedestrian adjust his velocity to the surrounding density), known as the fundamental diagram of the pedestrian flow. By the means of the cellular automaton, the simulation results fit well with the empirical data, indicating the great advance of the discrete model for pedestrian dynamics. The results suggest that the system velocity and flow rate increase obviously under a big noise, i.e., a diverse composition of pedestrian crowd, especially in the region of middle or high density. Because of the temporary effect, the speed matching has little influence on the fundamental diagram. Along the entire density, the relationship between the step length and the average pedestrian velocity is a piecewise function combined two linear functions. The number of conflicts reaches the maximum with the pedestrian density of 2.5 m-2, while decreases by 5.1% with the speed matching.

  17. Typical features of pedestrian spatial distribution in the inflow process

    NASA Astrophysics Data System (ADS)

    Liu, Xiaodong; Song, Weiguo; Fu, Libi; Lv, Wei; Fang, Zhiming

    2016-04-01

    Pedestrian inflow is frequently observed in various pedestrian facilities. In this work, we first proposed four hypotheses concerning the inflow process. Then, we performed a series of experiments to test the hypotheses. With several analytical methods, e.g., the proxemics theory and Voronoi diagram method, the features of pedestrian inflow are analyzed in detail. Results demonstrate that the distribution of pedestrians in the room is not uniform. Boundaries are attractive for these pedestrians. The impact of two factors of the inflow are analyzed, i.e., movement rule, and first-out reward. It is found pedestrians can enter the room more effectively under the random rule or two queues. Under some hurry circumstances, pedestrians may prefer to gather around the door, and the spatial distribution is not uniform, leading to the imbalance use of the room. Practical suggestions are given for pedestrians to improve the travel efficiency in the inflow process. This experimental study is meaningful to reveal some fundamental phenomena of inflow process, which can provide the realistic basis for building the theory and mathematical-physical models.

  18. Experimental characterization of collision avoidance in pedestrian dynamics.

    PubMed

    Parisi, Daniel R; Negri, Pablo A; Bruno, Luciana

    2016-08-01

    In the present paper, the avoidance behavior of pedestrians was characterized by controlled experiments. Several conflict situations were studied considering different flow rates and group sizes in crossing and head-on configurations. Pedestrians were recorded from above, and individual two-dimensional trajectories of their displacement were recovered after image processing. Lateral swaying amplitude and step lengths were measured for free pedestrians, obtaining similar values to the ones reported in the literature. Minimum avoidance distances were computed in two-pedestrian experiments. In the case of one pedestrian dodging an arrested one, the avoidance distance did not depend on the relative orientation of the still pedestrian with respect to the direction of motion of the first. When both pedestrians were moving, the avoidance distance in a perpendicular encounter was longer than the one obtained during a head-on approach. It was found that the mean curvature of the trajectories was linearly anticorrelated with the mean speed. Furthermore, two common avoidance maneuvers, stopping and steering, were defined from the analysis of the acceleration and curvature in single trajectories. Interestingly, it was more probable to observe steering events than stopping ones, also the probability of simultaneous steering and stopping occurrences was negligible. The results obtained in this paper can be used to validate and calibrate pedestrian dynamics models. PMID:27627328

  19. Severity of road crashes involving pedestrians in Metro Manila, Philippines.

    PubMed

    Verzosa, Nina; Miles, Rebecca

    2016-09-01

    Pedestrians are considered as one of the most vulnerable road users in less developed countries (LDCs). Yet, pedestrian safety remains poorly addressed in both urban and rural transportation plans in most LDCs. Since most pedestrian injury severity studies are conducted in developed countries, this study fills the gap with an inquiry focused on a highly urbanized region of an LDC that faces a rapid increase in car ownership and increasing pedestrian-related traffic injuries, documenting specific pedestrian safety issues and providing guidance for injury prevention measures in such places. Using the Metro Manila Accident Reporting and Analysis System (MMARAS) data from 2008 to 2011, this study combines binomial logistic regression and street level analysis that further explores the statistical results and examines other factors that contribute to collisions and increase the potential for serious injury or death in three cities in Metro Manila: Makati, Manila, and Quezon. The results of the binomial regression analysis show that traffic crashes that involve heavy and multiple vehicles, and an elderly pedestrian (60 years old and above), as well as those that occurred during the evening (7 pm to midnight) and late at night (1 am to 5 am) have significantly higher odds of resulting in a fatal outcome; when the crash involves a female pedestrian and when the road surface is wet the odds of a fatal outcome are lower. Moreover, by closely examining the environment of these roadways, the study finds that most pedestrian fatalities occur on high-speed, high-traffic-volume, multilane roadways, that are surrounded by land uses that generate a particularly problematic mix of heavy vehicular and pedestrian traffic. The street level analysis also finds that fatal pedestrian crashes occur close to different types of transit stations. The results of this study of three cities in Metro Manila, reflect the twofold challenge to pedestrian safety in rapidly urbanizing areas in

  20. Pedestrian Counting with Occlusion Handling Using Stereo Thermal Cameras.

    PubMed

    Kristoffersen, Miklas S; Dueholm, Jacob V; Gade, Rikke; Moeslund, Thomas B

    2016-01-01

    The number of pedestrians walking the streets or gathered in public spaces is a valuable piece of information for shop owners, city governments, event organizers and many others. However, automatic counting that takes place day and night is challenging due to changing lighting conditions and the complexity of scenes with many people occluding one another. To address these challenges, this paper introduces the use of a stereo thermal camera setup for pedestrian counting. We investigate the reconstruction of 3D points in a pedestrian street with two thermal cameras and propose an algorithm for pedestrian counting based on clustering and tracking of the 3D point clouds. The method is tested on two five-minute video sequences captured at a public event with a moderate density of pedestrians and heavy occlusions. The counting performance is compared to the manually annotated ground truth and shows success rates of 95.4% and 99.1% for the two sequences. PMID:26742047

  1. Pedestrian Counting with Occlusion Handling Using Stereo Thermal Cameras

    PubMed Central

    Kristoffersen, Miklas S.; Dueholm, Jacob V.; Gade, Rikke; Moeslund, Thomas B.

    2016-01-01

    The number of pedestrians walking the streets or gathered in public spaces is a valuable piece of information for shop owners, city governments, event organizers and many others. However, automatic counting that takes place day and night is challenging due to changing lighting conditions and the complexity of scenes with many people occluding one another. To address these challenges, this paper introduces the use of a stereo thermal camera setup for pedestrian counting. We investigate the reconstruction of 3D points in a pedestrian street with two thermal cameras and propose an algorithm for pedestrian counting based on clustering and tracking of the 3D point clouds. The method is tested on two five-minute video sequences captured at a public event with a moderate density of pedestrians and heavy occlusions. The counting performance is compared to the manually annotated ground truth and shows success rates of 95.4% and 99.1% for the two sequences. PMID:26742047

  2. Blind and sighted pedestrians' judgments of gaps in traffic at roundabouts.

    PubMed

    Guth, David; Ashmead, Daniel; Long, Richard; Wall, Robert; Ponchillia, Paul

    2005-01-01

    This paper reports two experiments about street crossing under conditions of free flowing traffic, with a focus on modem roundabout intersections. Experiment 1 was conducted at three roundabouts varying in size and traffic volume. Six totally blind and six sighted adults judged whether gaps in traffic were long enough to permit crossing to the median (splitter) island before the next vehicle arrived. Gap distributions and measures of judgment quality are reported. Overall, blind participants were about 2.5 times less likely to make correct judgments than sighted participants, took longer to detect crossable gaps, and were more likely to miss crossable gaps altogether. However, the differences were significant only at the two higher volume roundabouts. In Experiment 2, we evaluated the response of drivers to pedestrians with and without mobility devices (i.e., long canes, dog guides). The experiment was conducted at a single-lane roundabout, a midblock crossing, and a two-way-stop-controlled intersection. Site-specific characteristics appeared to have a greater impact on drivers' yielding than did a mobility device. Actual or potential applications of this research include the development of methods for assessing pedestrian safety and driver behavior as well as identifying intersections that may require modification in order to be accessible to blind pedestrians. PMID:16170941

  3. Does Excessive Daytime Sleepiness Affect Children's Pedestrian Safety?

    PubMed Central

    Avis, Kristin T.; Gamble, Karen L.; Schwebel, David C.

    2014-01-01

    Study Objectives: Many cognitive factors contribute to unintentional pedestrian injury, including reaction time, impulsivity, risk-taking, attention, and decision-making. These same factors are negatively influenced by excessive daytime sleepiness (EDS), which may place children with EDS at greater risk for pedestrian injury. Design, Participants, and Methods: Using a case-control design, 33 children age 8 to 16 y with EDS from an established diagnosis of narcolepsy or idiopathic hypersomnia (IHS) engaged in a virtual reality pedestrian environment while unmedicated. Thirty-three healthy children matched by age, race, sex, and household income served as controls. Results: Children with EDS were riskier pedestrians than healthy children. They were twice as likely to be struck by a virtual vehicle in the virtual pedestrian environment than healthy controls. Attentional skills of looking at oncoming traffic were not impaired among children with EDS, but decision-making for when to cross the street safely was significantly impaired. Conclusions: Results suggest excessive daytime sleepiness (EDS) from the clinical sleep disorders known as the hypersomnias of central origin may have significant consequences on children's daytime functioning in a critical domain of personal safety, pedestrian skills. Cognitive processes involved in safe pedestrian crossings may be impaired in children with EDS. In the pedestrian simulation, children with EDS appeared to show a pattern consistent with inattentional blindness, in that they “looked but did not process” information in their pedestrian environment. Results highlight the need for heightened awareness of potentially irreversible consequences of untreated sleep disorders and identify a possible target for pediatric injury prevention. Citation: Avis KT; Gamble KL; Schwebel DC. Does excessive daytime sleepiness affect children's pedestrian safety? SLEEP 2014;37(2):283-287. PMID:24497656

  4. Improving pedestrian detection using MPEG-7 descriptors

    NASA Astrophysics Data System (ADS)

    Lietz, H.; Ritter, M.; Manthey, R.; Wanielik, G.

    2013-07-01

    During the last decade, modern Pedestrian Detection Systems made massive use of the steadily growing numbers of high-performance image acquisition sensors. Within our naturalistic driving environment, a lot of different and heterogeneous scenes occur that are caused by varying illumination and weather conditions. Unfortunately, current systems do not work properly under these hardened conditions. The aim of this article is to investigate and evaluate observed video scenes from an open source dataset by using various image features in order to create a basis for robust and more accurate object detection.

  5. 10 CFR 431.224 - Uniform test method for the measurement of energy consumption for traffic signal modules and...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... for Traffic Signals,” Version 1.1, section 1, “Definitions,” and section 4, “Test Criteria... traffic signal modules and pedestrian modules. For purposes of 10 CFR part 431 and EPCA, the test... consumption for traffic signal modules and pedestrian modules. 431.224 Section 431.224 Energy DEPARTMENT...

  6. 10 CFR 431.224 - Uniform test method for the measurement of energy consumption for traffic signal modules and...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... for Traffic Signals,” Version 1.1, section 1, “Definitions,” and section 4, “Test Criteria... traffic signal modules and pedestrian modules. For purposes of 10 CFR part 431 and EPCA, the test... consumption for traffic signal modules and pedestrian modules. 431.224 Section 431.224 Energy DEPARTMENT...

  7. Psychological Differences toward Pedestrian Red Light Crossing between University Students and Their Peers.

    PubMed

    Suo, Qinghui; Zhang, Daming

    2016-01-01

    Based on our site investigation conducted in 2013, we found that the pedestrian red light crossing at the midblock connecting the campus of Southwest University and living area was low, where most of pedestrians are university students and staff. This paper reports a supplementary work applying the Theory of Planned Behaviour (TPB) to identify any psychological differences toward pedestrian red light crossing between university students and their peers. Three social groups participated in the investigation. The first group is the university students in Grade one (Group 1), the other two groups are their previous senior middle school classmates who are now working full time (Group 2) or who are now out of work and school (Group 3). The statistical results indicated The TPB components accounted for 42.9%, 55.3% and 55.4% of the variance of red signal crossing intention for Group 1, Group 2 and Group 3 in the depicted road crossing scenario. The data also showed that there are obvious differences among the participants' responses to "refrain from crossing" between university students and others, and the subsequent regression analysis revealed the ability to "refrain from crossing" played the most important role in the intention of red light crossing in the depicted scenario. PMID:26824667

  8. Psychological Differences toward Pedestrian Red Light Crossing between University Students and Their Peers

    PubMed Central

    Suo, Qinghui; Zhang, Daming

    2016-01-01

    Based on our site investigation conducted in 2013, we found that the pedestrian red light crossing at the midblock connecting the campus of Southwest University and living area was low, where most of pedestrians are university students and staff. This paper reports a supplementary work applying the Theory of Planned Behaviour (TPB) to identify any psychological differences toward pedestrian red light crossing between university students and their peers. Three social groups participated in the investigation. The first group is the university students in Grade one (Group 1), the other two groups are their previous senior middle school classmates who are now working full time (Group 2) or who are now out of work and school (Group 3). The statistical results indicated The TPB components accounted for 42.9%, 55.3% and 55.4% of the variance of red signal crossing intention for Group 1, Group 2 and Group 3 in the depicted road crossing scenario. The data also showed that there are obvious differences among the participants’ responses to “refrain from crossing” between university students and others, and the subsequent regression analysis revealed the ability to “refrain from crossing” played the most important role in the intention of red light crossing in the depicted scenario. PMID:26824667

  9. A signal processing system of fiber Bragg grating sensor based on code division multiplexing access

    NASA Astrophysics Data System (ADS)

    Li, Wei

    2013-09-01

    A lowcost Fiber Bragg Grating (FBG) Sensing System based on code division multiplexing access (CDMA) technology is proposed. The system using semiconductor optical amplifier and a broadband source is experimented. Without a tunable laser source or electro-optic switch driven, the price of system is very low. CDMA is used to separate each reflected sensor. The experimental results show that theory is correct.

  10. Mapping of the SecA signal peptide binding site and dimeric interface by using the substituted cysteine accessibility method.

    PubMed

    Bhanu, Meera K; Zhao, Ping; Kendall, Debra A

    2013-10-01

    SecA is an ATPase nanomotor critical for bacterial secretory protein translocation. Secretory proteins carry an amino-terminal signal peptide that is recognized and bound by SecA followed by its transfer across the SecYEG translocon. While this process is crucial for the onset of translocation, exactly where the signal peptide interacts with SecA is unclear. SecA protomers also interact among themselves to form dimers in solution, yet the oligomeric interface and the residues involved in dimerization are unknown. To address these issues, we utilized the substituted cysteine accessibility method (SCAM); we generated a library of 23 monocysteine SecA mutants and probed for the accessibility of each mutant cysteine to maleimide-(polyethylene glycol)2-biotin (MPB), a sulfhydryl-labeling reagent, both in the presence and absence of a signal peptide. Dramatic differences in MPB labeling were observed, with a select few mutants located at the preprotein cross-linking domain (PPXD), the helical wing domain (HWD), and the helical scaffold domain (HSD), indicating that the signal peptide binds at the groove formed between these three domains. The exposure of this binding site is varied under different conditions and could therefore provide an ideal mechanism for preprotein transfer into the translocon. We also identified residues G793, A795, K797, and D798 located at the two-helix finger of the HSD to be involved in dimerization. Adenosine-5'-(γ-thio)-triphosphate (ATPγS) alone and, more extensively, in conjunction with lipids and signal peptides strongly favored dimer dissociation, while ADP supports dimerization. This study provides key insight into the structure-function relationships of SecA preprotein binding and dimer dissociation. PMID:23935053

  11. Assessment of effectiveness of signal-code constructions in time division-multi-access satellite systems

    NASA Astrophysics Data System (ADS)

    Portnoy, S. L.; Ankudinov, D. R.

    1985-01-01

    Energy losses in TDMA satellite circuits are investigated on the basis of the model of a Gaussian memoryless channel incorporating a signal code construction. The signal code construction is a consolidated two stage construction with a modulation system as the inner stage and correcting codes as the outer stage. Signal code constructions employing Gray codes, cascade codes and M-ary block codes are considered. Real TDMA systems are analyzed on the assumptions that the calculations are made using an audio frequency equivalent of the circuit, the relay carries a single trunk, the timing and carrier frequency synchronization is ideal, the signal is transmitted in the continuous stream, and there is no noise at the input of the receiving filter. The effectiveness of a signal code construction employing cascade codes on a real satellite link incorporating MDVU-40 equipment is modeled. The method can be used to select the signal code construction in a communications channel for the required data rate, and to maximize the energy gain and attainable transmission rate over the relay trunk.

  12. An improved algorithm for pedestrian detection

    NASA Astrophysics Data System (ADS)

    Yousef, Amr; Duraisamy, Prakash; Karim, Mohammad

    2015-03-01

    In this paper we present a technique to detect pedestrian. Histogram of gradients (HOG) and Haar wavelets with the aid of support vector machines (SVM) and AdaBoost classifiers show good identification performance on different objects classification including pedestrians. We propose a new shape descriptor derived from the intra-relationship between gradient orientations in a way similar to the HOG. The proposed descriptor is a two 2-D grid of orientation similarities measured at different offsets. The gradient magnitudes and phases derived from a sliding window with different scales and sizes are used to construct two 2-D symmetric grids. The first grid measures the co-occurence of the phases while the other one measures the corresponding percentage of gradient magnitudes for the measured orientation similarity. Since the resultant matrices will be symmetric, the feature vector is formed by concatenating the upper diagonal grid coefficients collected in a raster way. Classification is done using SVM classifier with radial basis kernel. Experimental results show improved performance compared to the current state-of-art techniques.

  13. Effects of Switching Behavior for the Attraction on Pedestrian Dynamics

    PubMed Central

    Kwak, Jaeyoung; Jo, Hang-Hyun; Luttinen, Tapio; Kosonen, Iisakki

    2015-01-01

    Walking is a fundamental activity of our daily life not only for moving to other places but also for interacting with surrounding environment. While walking on the streets, pedestrians can be aware of attractions like shopping windows. They can be influenced by the attractions and some of them might shift their attention towards the attractions, namely switching behavior. As a first step to incorporate the switching behavior, this study investigates collective effects of switching behavior for an attraction by developing a behavioral model. Numerical simulations exhibit different patterns of pedestrian behavior depending on the strength of the social influence and the average length of stay. When the social influence is strong along with a long length of stay, a saturated phase can be defined at which all the pedestrians have visited the attraction. If the social influence is not strong enough, an unsaturated phase appears where one can observe that some pedestrians head for the attraction while others walk in their desired direction. These collective patterns of pedestrian behavior are summarized in a phase diagram by comparing the number of pedestrians who visited the attraction to the number of passersby near the attraction. Measuring the marginal benefits with respect to the strength of the social influence and the average length of stay enables us to identify under what conditions enhancing these variables would be more effective. The findings from this study can be understood in the context of the pedestrian facility management, for instance, for retail stores. PMID:26218430

  14. A Langevin model for low density pedestrian dynamics

    NASA Astrophysics Data System (ADS)

    Corbetta, Alessandro; Lee, Chung-Min; Benzi, Roberto; Muntean, Adrian; Toschi, Federico

    The dynamics of pedestrian crowds shares deep connections with statistical physics and fluid dynamics. Reaching a quantitative understanding, not only of the average behaviours but also of the statistics of (rare) fluctuations would have major impact, for instance, on the design and safety of civil infrastructures. A key feature of pedestrian dynamics is its strong intrinsic variability, that we can already observe at the single individual level. In this work we aim at a quantitative characterisation of this statistical variability by studying individual fluctuations. We consider experimental observations of low-density pedestrian flows in a corridor within a building at Eindhoven University of Technology. Few hundreds of thousands of pedestrian trajectories with high space and time resolutions have been collected via a Microsoft Kinect 3D-range sensor and automatic head tracking techniques. From these observations we model pedestrians as active Brownian particles by means of a generalised Langevin equation. With this model we can quantitatively reproduce the observed dynamics including the statistics of ordinary pedestrian fluctuations and of rarer U-turn events. Low density, pair-wise interactions between pedestrians are also discussed.

  15. Mapping patterns of pedestrian fatal accidents in Israel.

    PubMed

    Prato, Carlo Giacomo; Gitelman, Victoria; Bekhor, Shlomo

    2012-01-01

    This study intends to provide insight into pedestrian accidents by uncovering their patterns in order to design preventive measures and to allocate resources for identified problems. Kohonen neural networks are applied to a database of pedestrian fatal accidents occurred during the four-year period between 2003 and 2006. Results show the existence of five pedestrian accident patterns: (i) elderly pedestrians crossing on crosswalks mostly far from intersections in metropolitan areas; (ii) pedestrians crossing suddenly or from hidden places and colliding with two-wheel vehicles on urban road sections; (iii) male pedestrians crossing at night and being hit by four-wheel vehicles on rural road sections; (iv) young male pedestrians crossing at night wide road sections in both urban and rural areas; (v) children and teenagers crossing road sections in small rural communities. From the perspective of preventive measures, results suggest the necessity of designing education and information campaigns for road users as well as allocating resources for infrastructural interventions and law enforcement in order to address the identified major problems. PMID:22062337

  16. Does communication enhance pedestrians transport in the dark?

    NASA Astrophysics Data System (ADS)

    Cirillo, Emilio N. M.; Colangeli, Matteo; Muntean, Adrian

    2016-01-01

    We study the motion of pedestrians through an obscure tunnel where the lack of visibility hides the exits. Using a lattice model, we explore the effects of communication on the effective transport properties of the crowd of pedestrians. More precisely, we study the effect of two thresholds on the structure of the effective nonlinear diffusion coefficient. One threshold models pedestrian communication efficiency in the dark, while the other one describes the tunnel capacity. Essentially, we note that if the evacuees show a maximum trust (leading to a fast communication), they tend to quickly find the exit and hence the collective action tends to prevent the occurrence of disasters.

  17. Pedestrian Injury Patterns and Risk in Minibus Collisions in China

    PubMed Central

    Li, Kui; Fan, Xiaoxiang; Yin, Zhiyong

    2015-01-01

    Background The minibus, with a nearly flat front, is widely used in China, especially in the underdeveloped regions, and results in large numbers of pedestrian injuries and deaths. The purpose of this study was to determine the injury patterns and risk for pedestrians involved in these crashes. Material/Methods We conducted an in-depth investigation of minibus/pedestrian accidents in Chongqing, China, occurring between September 2000 and April 2014. The enrolled pedestrians was classified into 3 groups: young (aged 14–44 years), middle-aged (aged 45–59 years), and elderly (aged over 60 years). Pedestrian injuries were coded according to the Abbreviated Injury Scale (AIS). Results A total of 109 pedestrians, with an average age of 55.7±16.2 years, were injured or killed – 30.3% were young, 23.9% were middle-aged, and 45.9% were elderly. Pedestrians hit by a minibus had a high proportion of head, chest, and extremity injuries – 84.4%, 50.5%, and 52.3%, respectively. In addition, impact speeds in excess of 75 km/h all ultimately resulted in fatalities. At an impact speed of 30 km/h, the risk of pedestrian fatality and AIS3+ injury are approximately 12.0% and 37.2%, respectively. At 50 km/h the risks are 65.2% and 96.9%, respectively, and at 70 km/h the risks are 96.3% and 99.9%, respectively. Conclusions A higher likelihood of chest injury was associated with being older and impact speed of over 40 km/h in minibus/pedestrian collision. Our data suggest that the injury patterns of pedestrians in minibus collisions differ from that in other vehicle/pedestrian collisions. These findings could contribute to better understanding of the injury patterns and risk of pedestrian in minibus collisions in China, which may play an important role in developing measures to improve traffic safety. PMID:25754962

  18. 33 CFR 105.106 - Public access areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... within a facility that is open to all persons and provides pedestrian access through the facility from... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Public access areas. 105.106... SECURITY MARITIME SECURITY: FACILITIES General § 105.106 Public access areas. (a) A facility...

  19. Full-duplex fiber-wireless link with 40 Gbit/s 16-QAM signals for alternative wired and wireless accesses based on homodyne/heterodyne coherent detection

    NASA Astrophysics Data System (ADS)

    Zhang, Ruijiao; Ma, Jianxin; Wang, Zhao; Zhang, Junjie; Li, Yanjie; Zheng, Guoli; Liu, Wen; Yu, Jianguo; Zhang, Qi; Wang, Qin; Liu, Renhao

    2014-06-01

    A novel full-duplex fiber-wireless link with 40 Gbit/s 16-ary quadrature amplitude modulation (QAM) signals is proposed to provide alternative wired and wireless accesses for the user terminals. In the central station (CS), the downstream signal for wired and wireless accesses is beared onto the CW laser source via an optical I/Q modulator to realize the QAM modulation. At the hybrid optical network unit (HONU), a tunable laser is used to provide coherent optical local oscillator for homo-/heterodyne beating to coherently down-convert the baseband optical signal to the baseband electrical one for wired access or to the mm-wave one for wireless access according to the requirement of the user terminals. Simultaneously, the lightwave from the tunable laser is also used as the uplink optical carrier for either wired or wireless access, and is modulated colorlessly by the baseband or mm-wave signal of the uplink alternatively. After filtering, only one tone carrying the uplink signal is transmitted back to the CS even for the wireless access. The theoretical analysis and simulation results show that our proposed full-duplex link for the alternative wired and wireless accesses maintains good performance even when the transmission link with standard single mode fiber (SSMF) is extended to 30 km.

  20. Photonics-assistant spectra shaping of ultra-wideband signals for dynamic spectrum access in cognitive network

    NASA Astrophysics Data System (ADS)

    Zheng, Jianyu; Zhu, Ninghua; Wang, Lixian; Wang, Hui; Du, Yuanxin; Liu, Jianguo

    2012-11-01

    The dynamic control for the spectra of the Ultra-wideband (UWB) signals, which is the key for implementing the dynamic spectrum access in the cognitive radio, is still a challenge due to the limited processing speed of the electronic devices. In this paper, we have summarized our recent work about controlling the spectrum shape of the UWB signals in optical domain, in addition to reviewing the other groups' related research work. The experiment setups and results based on nonlinear dynamics of the optoelectronic oscillator and transfer response of the phase or polarization-to-intensity convertor will be described in detail respectively, in which the controllable frequency suppress for the optical UWB signals at specific frequency positions were implemented. Particularly, the UWB pulse with the special shape, which corresponds to the 5-GHz band-rejection in frequency domain, was generated in order to avoid the interference between UWB and Wireless Fidelity system in practice. In addition, the UWB signals whose center frequency could be continuously tuned and converted up to the frequency range of millimeter wave were generated by utilizing the polarization modulator based optical switch. The areas for future development and the challenge of implementing these techniques for the applications in practice will also be discussed.

  1. Alternative Wired and 60-GHz Wireless Full Duplex Access Based on a Polarization Orthogonal Dual-Tone Optical Millimeter-Wave Signal

    NASA Astrophysics Data System (ADS)

    Ma, Jianxin; Zhang, Ruijiao; Zhang, Junjie; Xin, Xiangjun

    2015-11-01

    A novel full duplex fiber wireless link providing alternative wired and 60-GHz wireless access is proposed based on a polarization orthogonal dual-tone optical millimeter-wave signal. In a hybrid optical network unit, the downlink optical signal can be decomposed as a single-sideband optical millimeter-wave signal (baseband optical signal) for wireless (wired) access by a polarization controller and polarization beam splitter. The uplink optical carrier abstracted from the downlink optical signal makes the hybrid optical network unit free from the optical source. The simulation results show that both downlinks and uplinks for either wired or wireless access can maintain quite good performance over 60 km of fiber.

  2. Full duplex fiber link for alternative wired and wireless access based on SSB optical millimeter-wave with 4-PAM signal

    NASA Astrophysics Data System (ADS)

    Ma, Jianxin; Zhang, Junjie

    2015-03-01

    A novel full-duplex fiber-wireless link based on single sideband (SSB) optical millimeter (mm)-wave with 10 Gbit/s 4-pulse amplitude modulation (PAM) signal is proposed to provide alternative wired and 40 GHz wireless accesses for the user terminals. The SSB optical mm-wave with 4-PAM signal consists of two tones: one bears the 4-PAM signal and the other is unmodulated with high power. After transmission over the fiber to the hybrid optical network unit (HONU), the SSB optical mm-wave signal can be decomposed by fiber Bragg gratings (FBGs) as the SSB optical mm-wave signal with reduced carrier-to-sideband ratio (the baseband 4-PAM optical signal) and the uplink optical carrier for the wireless (wired) access. This makes the HONU free from the laser source. For the uplink, since the wireless access signal is converted to the baseband by power detection, both the transmitter in the HONU and the receiver in optical line terminal (OLT) are co-shared for both wireless and wired accesses, which makes the full duplex link much simpler. In our scheme, the optical electrical field of the square-root increment level 4-PAM signal assures an equal level spacing receiving for both the downlink wired and wireless accesses. Since the downlink wireless signal is down-converted to the baseband by power detection, RF local oscillator is unnecessary. To confirm the feasibility of our proposed scheme, a simulation full duplex link with 40 GHz SSB optical mm-wave with 10 Gbit/s 4-PAM signal is built. The simulation results show that both down- and up-links for either wired or wireless access can keep good performance even if the link length of the SSMF is extended to 40 km.

  3. Features of the Vision of Elderly Pedestrians when Crossing a Road.

    PubMed

    Matsui, Yasuhiro; Oikawa, Shoko; Aoki, Yoshio; Sekine, Michiaki; Mitobe, Kazutaka

    2014-11-01

    The present study clarifies the mechanism by which an accident occurs when an elderly pedestrian crosses a road in front of a car, focusing on features of the central and peripheral vision of elderly pedestrians who are judging when it is safe to cross the road. For the pedestrian's central visual field, we investigated the effect of age on the timing judgment using an actual car. The results for daytime conditions indicate that the elderly pedestrians tended to make later judgments of when they crossed the road from the right side of the driver's view at high car velocities. At night, for a car with its headlights on high beam, the average car-pedestrian distances of elderly pedestrians on the left side of the driver's view were significantly longer than those of young pedestrians at velocities of 20 and 40 km/h. The eyesight of the elderly pedestrians during the day did not affect the timing judgment of crossing a road. At night, for a car with its headlights on either high or low beam, the average car-pedestrian distances of elderly pedestrians having good eyesight were longer than those of elderly pedestrians having poor eyesight, for all car velocities. The color of the car body in the central visual field did not affect the timing judgment of elderly pedestrians crossing the road. Meanwhile, the car-body color in the elderly pedestrian's peripheral vision strongly affected the pedestrian's awareness of the car. PMID:26192957

  4. 4. CONTEXT VIEW SHOWING SOUTHWEST FACADE, SOUTHEAST FACADE, PEDESTRIAN APPROACH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. CONTEXT VIEW SHOWING SOUTHWEST FACADE, SOUTHEAST FACADE, PEDESTRIAN APPROACH AND GARAGE (IN THE BACKGROUND). VIEW TO NORTH. - Thompson Falls Hydroelectric Project, Power Foreman's Bungalow, On island between Forebay Channel & ClarkFord River, Thompson Falls, Sanders County, MT

  5. Internal pedestrian circulation and common open space, also illustrating mature ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Internal pedestrian circulation and common open space, also illustrating mature landscape features. Building 35 at left foreground. Facing east - Harbor Hills Housing Project, 26607 Western Avenue, Lomita, Los Angeles County, CA

  6. EXTERIOR VIEW, POWELL AVENUE (SOUTH) ELEVATION, PEDESTRIAN PASSAGEWAY AT LEFT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR VIEW, POWELL AVENUE (SOUTH) ELEVATION, PEDESTRIAN PASSAGEWAY AT LEFT SIDE OF UNDERPASS - Twentieth Street Underpass, At Railroad Reservation, Twentieth Street at the Tracks between Morris & Powell Avenues, Birmingham, Jefferson County, AL

  7. 20. VIEW, LOOKING NORTH FROM BOSTON, SHOWING RAILING, PEDESTRIAN STAIR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. VIEW, LOOKING NORTH FROM BOSTON, SHOWING RAILING, PEDESTRIAN STAIR, AND '10 SMOOT' MARKER (see data pages) - Harvard Bridge, Spanning Charles River at Massachusetts Avenue, Boston, Suffolk County, MA

  8. Pedestrian simulations in hexagonal cell local field model

    NASA Astrophysics Data System (ADS)

    Leng, Biao; Wang, Jianyuan; Xiong, Zhang

    2015-11-01

    Pedestrian dynamics have caused wide concern over the recent years. This paper presents a local field (LF) model based on regular hexagonal cells to simulate pedestrian dynamics in scenarios such as corridors and bottlenecks. In this model, the simulation scenarios are discretized into regular hexagonal cells. The local field is a small region around pedestrian. Each pedestrian will choose his/her target cell according to the situation in his/her local field. Different walking strategies are considered in the simulation in corridor scenario and the fundamental graphs are used to verify this model. Different shapes of exit are also discussed in the bottleneck scenario. The statistics of push effect show that the smooth bottleneck exit may be more safe.

  9. Study on bi-directional pedestrian movement using ant algorithms

    NASA Astrophysics Data System (ADS)

    Sibel, Gokce; Ozhan, Kayacan

    2016-01-01

    A cellular automata model is proposed to simulate bi-directional pedestrian flow. Pedestrian movement is investigated by using ant algorithms. Ants communicate with each other by dropping a chemical, called a pheromone, on the substrate while crawling forward. Similarly, it is considered that oppositely moving pedestrians drop ‘visual pheromones’ on their way and the visual pheromones might cause attractive or repulsive interactions. This pheromenon is introduced into modelling the pedestrians’ walking preference. In this way, the decision-making process of pedestrians will be based on ‘the instinct of following’. At some densities, the relationships of velocity-density and flux-density are analyzed for different evaporation rates of visual pheromones. Lane formation and phase transition are observed for certain evaporation rates of visual pheromones.

  10. UNDERSIDE. NOTE DOUBLE BEAMS CANTILEVERED FOR PEDESTRIAN WALKWAY. DATE ADDED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    UNDERSIDE. NOTE DOUBLE BEAMS CANTILEVERED FOR PEDESTRIAN WALKWAY. DATE ADDED TO BRIDGE UNKNOWN, BUT PROBABLY 1921-22 OR AFTER 1927. - Bath-Haverhill Bridge, Spanning Ammonoosuc River, bypassed section of Ammanoosuc Street (SR 135), Woodsville, Grafton County, NH

  11. 47. PLANS FOR EXISTING THREESPAN PEDESTRIAN BRIDGE OVER GRAND CANAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. PLANS FOR EXISTING THREE-SPAN PEDESTRIAN BRIDGE OVER GRAND CANAL AT 25TH AVENUE Plan Sheet D-5117 (delineated by R. H. Bacon, April 1939) - Venice Canals, Community of Venice, Los Angeles, Los Angeles County, CA

  12. 17. View of masonry gatehouse, safety gates and pedestrian waiting ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. View of masonry gatehouse, safety gates and pedestrian waiting shelter with ripped copper roofing and missing columns. (Nov. 30, 1988) - University Heights Bridge, Spanning Harlem River at 207th Street & West Harlem Road, New York County, NY

  13. THREEQUARTER VIEW FROM PEDESTRIAN PATH LEVEL, LOOKING SOUTHEAST, SHOWING BALUSTRADE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    THREE-QUARTER VIEW FROM PEDESTRIAN PATH LEVEL, LOOKING SOUTHEAST, SHOWING BALUSTRADE AND WEST ELEVATION OF BRIDGE. - Central Park Bridges, Gothic Arch, Spanning bridlepath south of tennis courts at northwest edge of Reservoir, Central Park, New York County, NY

  14. 3. Threequarter view from pedestrian path level, looking southeast, showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Three-quarter view from pedestrian path level, looking southeast, showing balustrade and west elevation of bridge - Central Park Bridges, Gothic Arch, Spanning bridlepath south of tennis courts at northwest edge of Reservoir, Central Park, New York County, NY

  15. 42. Detail, subdeck viaduct showing riveted brackets supporting pedestrian walkway ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. Detail, sub-deck viaduct showing riveted brackets supporting pedestrian walkway and heavily reinforced concrete of traffic roadway: note granite blocks atop pier. - Broadway Bridge, Spanning Foundry Street, MBTA Yard, Fort Point Channel, & Lehigh Street, Boston, Suffolk County, MA

  16. 36 CFR 910.17 - Pedestrian circulation system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.17 Pedestrian circulation...

  17. 36 CFR 910.17 - Pedestrian circulation system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.17 Pedestrian circulation...

  18. 36 CFR 910.17 - Pedestrian circulation system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.17 Pedestrian circulation...

  19. 36 CFR 910.17 - Pedestrian circulation system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.17 Pedestrian circulation...

  20. 36 CFR 910.17 - Pedestrian circulation system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... GENERAL GUIDELINES AND UNIFORM STANDARDS FOR URBAN PLANNING AND DESIGN OF DEVELOPMENT WITHIN THE PENNSYLVANIA AVENUE DEVELOPMENT AREA Urban Planning and Design Concerns § 910.17 Pedestrian circulation...

  1. [Severity of injury of alcohol intoxicated pedestrians in street traffic].

    PubMed

    Mittmeyer, H J

    1991-01-01

    The evaluation of 251 autopsy cases of pedestrians who suffered fatal accidents in road traffic documents that the influence of alcohol entails an additional risk of injury for pedestrians in motor car accidents. In particular, severe trauma to the head, thorax and abdomen occur, whilst injuries to the pelvis and limbs are generally not more serious than in sober pedestrians. In the classical collision constellation of the pedestrian at the front end of cars, the upper part of the body is evidently especially endangered in the further movement phase. This phenomenon might be connected above all with the impairment of the voluntary reaction capacity due to alcohol during the sequence of evidents in the accident. PMID:1811504

  2. REBoost: probabilistic resampling for boosted pedestrian detection

    NASA Astrophysics Data System (ADS)

    Lai, Shiming; Liu, Yu; Zhang, Maojun; Theobald, Barry-John

    2011-12-01

    Cascaded object detectors have demonstrated great success in fast object detection, where image regions can quickly be rejected using a cascade of increasingly complex rejectors/detectors. Although such cascaded detectors typically are fast and require minimal computation, they usually require iterative training, where classifiers are retrained to optimize rejection thresholds after testing on a validation set. We propose a cascaded object detector that uses probabilistic resampling for boosting reweighting, which has the advantage that only a single training step is required. Decision thresholds can be tuned on a validation set without the need for classifier retraining. Empirical results on a pedestrian detection task demonstrate that this reweighting results in a strong classifier that quickly rejects image regions and offers higher accuracy than other competing approaches.

  3. Consistent evolution in a pedestrian flow

    NASA Astrophysics Data System (ADS)

    Guan, Junbiao; Wang, Kaihua

    2016-03-01

    In this paper, pedestrian evacuation considering different human behaviors is studied by using a cellular automaton (CA) model combined with the snowdrift game theory. The evacuees are divided into two types, i.e. cooperators and defectors, and two different human behaviors, herding behavior and independent behavior, are investigated. It is found from a large amount of numerical simulations that the ratios of the corresponding evacuee clusters are evolved to consistent states despite 11 typically different initial conditions, which may largely owe to self-organization effect. Moreover, an appropriate proportion of initial defectors who are of herding behavior, coupled with an appropriate proportion of initial defectors who are of rationally independent thinking, are two necessary factors for short evacuation time.

  4. VIEW OF ARROYO SECO CHANNEL PEDESTRIAN FOOTBRIDGE LOCATED IN ARROYO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF ARROYO SECO CHANNEL PEDESTRIAN FOOTBRIDGE LOCATED IN ARROYO SECO PARK, JUST SOUTH OF AVENUE 60 BRIDGE OVER THE ARROYO SECO PARKWAY. THIS BRIDGE WAS THE FIRST PRESTRESSED CONCRETE BRIDGE ERECTED WEST OF THE MISSISSIPPI WHEN IT WAS HOISTED INTO PLACE IN 1951. LOOKING 26°NNE - Arroyo Seco Channel Pedestrian Bridge, Spanning Arroyo Seco Channel south of Avenue 60, Arroyo Seco Park, Los Angeles, Los Angeles County, CA

  5. STEPPING - Smartphone-Based Portable Pedestrian Indoor Navigation

    NASA Astrophysics Data System (ADS)

    Lukianto, C.; Sternberg, H.

    2011-12-01

    Many current smartphones are fitted with GPS receivers, which, in combination with a map application form a pedestrian navigation system for outdoor purposes. However, once an area with insufficient satellite signal coverage is entered, these navigation systems cease to function. For indoor positioning, there are already several solutions available which are usually based on measured distances to reference points. These solutions can achieve resolutions as low as the sub-millimetre range depending on the complexity of the set-up. STEPPING project, developed at HCU Hamburg Germany aims at designing an indoor navigation system consisting of a small inertial navigation system and a new, robust sensor fusion algorithm running on a current smartphone. As this system is theoretically able to integrate any available positioning method, it is independent of a particular method and can thus be realized on a smartphone without affecting user mobility. Potential applications include --but are not limited to: Large trade fairs, airports, parking decks and shopping malls, as well as ambient assisted living scenarios.

  6. Analysis of dynamic road risk for pedestrian evacuation

    NASA Astrophysics Data System (ADS)

    Zhang, Nan; Huang, Hong; Su, Boni; Zhao, Jinlong

    2015-07-01

    Knowing the dynamic road risk for pedestrian evacuation and having an efficient evacuation plan play a very important role in the serious disasters such as earthquake, tsunami and hurricane. In this paper, the dynamic road risk for pedestrian evacuation in a densely populated area of Beijing was studied with consideration of different influencing factors. Firstly, the eight influencing factors including road width, node degree, safety betweenness, road resistor coefficient, building threat, pedestrian counterflow, illegal vehicle parking and traffic flow were considered to assess the road risk for pedestrian evacuation. Secondly, based on complex network theory, electric circuit theory and real situation of the roads, the comprehensive assessment function for road risk was developed quantitatively based on the eight influencing factors. Thirdly, we analyzed road risk for pedestrian evacuation considering different situations: current condition, regular condition, and optimal condition; the risk distribution maps were drawn to directly show the risk level. Through assessments, the roads with high risk for pedestrian evacuation were found, and an optimized evacuation plan was obtained and analyzed. This mathematical model can guide the emergency evacuation in real time. The process and the results are essential for improving the efficiency of evacuations which should considerably reduce the possibility of injuries, deaths and other losses in the disaster.

  7. Pedestrian Detection by Laser Scanning and Depth Imagery

    NASA Astrophysics Data System (ADS)

    Barsi, A.; Lovas, T.; Molnar, B.; Somogyi, A.; Igazvolgyi, Z.

    2016-06-01

    Pedestrian flow is much less regulated and controlled compared to vehicle traffic. Estimating flow parameters would support many safety, security or commercial applications. Current paper discusses a method that enables acquiring information on pedestrian movements without disturbing and changing their motion. Profile laser scanner and depth camera have been applied to capture the geometry of the moving people as time series. Procedures have been developed to derive complex flow parameters, such as count, volume, walking direction and velocity from laser scanned point clouds. Since no images are captured from the faces of pedestrians, no privacy issues raised. The paper includes accuracy analysis of the estimated parameters based on video footage as reference. Due to the dense point clouds, detailed geometry analysis has been conducted to obtain the height and shoulder width of pedestrians and to detect whether luggage has been carried or not. The derived parameters support safety (e.g. detecting critical pedestrian density in mass events), security (e.g. detecting prohibited baggage in endangered areas) and commercial applications (e.g. counting pedestrians at all entrances/exits of a shopping mall).

  8. Feature Selection and Pedestrian Detection Based on Sparse Representation.

    PubMed

    Yao, Shihong; Wang, Tao; Shen, Weiming; Pan, Shaoming; Chong, Yanwen; Ding, Fei

    2015-01-01

    Pedestrian detection have been currently devoted to the extraction of effective pedestrian features, which has become one of the obstacles in pedestrian detection application according to the variety of pedestrian features and their large dimension. Based on the theoretical analysis of six frequently-used features, SIFT, SURF, Haar, HOG, LBP and LSS, and their comparison with experimental results, this paper screens out the sparse feature subsets via sparse representation to investigate whether the sparse subsets have the same description abilities and the most stable features. When any two of the six features are fused, the fusion feature is sparsely represented to obtain its important components. Sparse subsets of the fusion features can be rapidly generated by avoiding calculation of the corresponding index of dimension numbers of these feature descriptors; thus, the calculation speed of the feature dimension reduction is improved and the pedestrian detection time is reduced. Experimental results show that sparse feature subsets are capable of keeping the important components of these six feature descriptors. The sparse features of HOG and LSS possess the same description ability and consume less time compared with their full features. The ratios of the sparse feature subsets of HOG and LSS to their full sets are the highest among the six, and thus these two features can be used to best describe the characteristics of the pedestrian and the sparse feature subsets of the combination of HOG-LSS show better distinguishing ability and parsimony. PMID:26295480

  9. Robust Pedestrian Classification Based on Hierarchical Kernel Sparse Representation.

    PubMed

    Sun, Rui; Zhang, Guanghai; Yan, Xiaoxing; Gao, Jun

    2016-01-01

    Vision-based pedestrian detection has become an active topic in computer vision and autonomous vehicles. It aims at detecting pedestrians appearing ahead of the vehicle using a camera so that autonomous vehicles can assess the danger and take action. Due to varied illumination and appearance, complex background and occlusion pedestrian detection in outdoor environments is a difficult problem. In this paper, we propose a novel hierarchical feature extraction and weighted kernel sparse representation model for pedestrian classification. Initially, hierarchical feature extraction based on a CENTRIST descriptor is used to capture discriminative structures. A max pooling operation is used to enhance the invariance of varying appearance. Then, a kernel sparse representation model is proposed to fully exploit the discrimination information embedded in the hierarchical local features, and a Gaussian weight function as the measure to effectively handle the occlusion in pedestrian images. Extensive experiments are conducted on benchmark databases, including INRIA, Daimler, an artificially generated dataset and a real occluded dataset, demonstrating the more robust performance of the proposed method compared to state-of-the-art pedestrian classification methods. PMID:27537888

  10. Feature Selection and Pedestrian Detection Based on Sparse Representation

    PubMed Central

    Yao, Shihong; Wang, Tao; Shen, Weiming; Pan, Shaoming; Chong, Yanwen; Ding, Fei

    2015-01-01

    Pedestrian detection have been currently devoted to the extraction of effective pedestrian features, which has become one of the obstacles in pedestrian detection application according to the variety of pedestrian features and their large dimension. Based on the theoretical analysis of six frequently-used features, SIFT, SURF, Haar, HOG, LBP and LSS, and their comparison with experimental results, this paper screens out the sparse feature subsets via sparse representation to investigate whether the sparse subsets have the same description abilities and the most stable features. When any two of the six features are fused, the fusion feature is sparsely represented to obtain its important components. Sparse subsets of the fusion features can be rapidly generated by avoiding calculation of the corresponding index of dimension numbers of these feature descriptors; thus, the calculation speed of the feature dimension reduction is improved and the pedestrian detection time is reduced. Experimental results show that sparse feature subsets are capable of keeping the important components of these six feature descriptors. The sparse features of HOG and LSS possess the same description ability and consume less time compared with their full features. The ratios of the sparse feature subsets of HOG and LSS to their full sets are the highest among the six, and thus these two features can be used to best describe the characteristics of the pedestrian and the sparse feature subsets of the combination of HOG-LSS show better distinguishing ability and parsimony. PMID:26295480

  11. IL-11/IL11RA receptor mediated signaling: a web accessible knowledgebase.

    PubMed

    Balakrishnan, Lavanya; Soman, Sowmya; Patil, Yatish B; Advani, Jayshree; Thomas, Joji Kurian; Desai, Dattatraya Venkatesh; Kulkarni-Kale, Urmila; Harsha, H C; Prasad, T S Keshava; Raju, Rajesh; Pandey, Akhilesh; Dimitriadis, Eva; Chatterjee, Aditi

    2013-08-01

    Abstract Interleukin-11 (IL-11) is a pleiotropic cytokine that belongs to gp130 family. It plays a significant role in the synthesis and maturation of hematopoietic cells, inhibition of adipogenesis, regulation of embryo implantation, and trophoblasts invasion. Although IL-11 signaling has been described in several biological processes, a centralized resource documenting these molecular reactions induced by IL-11 is not publicly available. In the current study, we have manually annotated the molecular reactions and interactions induced by IL-11 from literature available. We have documented 40 unique molecules involved in 18 protein-protein interactions, 26 enzyme-substrate reactions, 7 translocation events, and 4 activation/ inhibition reactions. We have also annotated 23 genes reported to be differentially regulated under IL-11 stimulation. We have enabled the data availability in standard exchange formats from 'NetPath', a repository for signaling pathways. We believe that this will help in the identification of potential therapeutic targets in IL-11-associated disorders. PMID:23631681

  12. TLR4 signaling augments B lymphocyte migration and overcomes the restriction that limits access to germinal center dark zones

    PubMed Central

    Hwang, Il-Young; Park, Chung; Harrison, Kathleen

    2009-01-01

    B lymphocyte–intrinsic Toll-like receptor (TLR) signals amplify humoral immunity and can exacerbate autoimmune diseases. We identify a new mechanism by which TLR signals may contribute to autoimmunity and chronic inflammation. We show that TLR4 signaling enhances B lymphocyte trafficking into lymph nodes (LNs), induces B lymphocyte clustering and interactions within LN follicles, leads to sustained in vivo B cell proliferation, overcomes the restriction that limits the access of nonantigen-activated B cells to germinal center dark zones, and enhances the generation of memory and plasma cells. Intravital microscopy and in vivo tracking studies of B cells transferred to recipient mice revealed that TLR4-activated, but not nonstimulated, B cells accumulated within the dark zones of preexisting germinal centers even when transferred with antigen-specific B cells. The TLR4-activated cells persist much better than nonstimulated cells, expanding both within the memory and plasma cell compartments. TLR-mediated activation of B cells may help to feed and stabilize the spontaneous and ectopic germinal centers that are so commonly found in autoimmune individuals and that accompany chronic inflammation. PMID:19917774

  13. Use of High Sensitivity GNSS Receiver Doppler Measurements for Indoor Pedestrian Dead Reckoning

    PubMed Central

    He, Zhe; Renaudin, Valérie; Petovello, Mark G.; Lachapelle, Gérard

    2013-01-01

    Dead-reckoning (DR) algorithms, which use self-contained inertial sensors combined with gait analysis, have proven to be effective for pedestrian navigation purposes. In such DR systems, the primary error is often due to accumulated heading drifts. By tightly integrating global navigation satellite system (GNSS) Doppler measurements with DR, such accumulated heading errors can usually be accurately compensated. Under weak signal conditions, high sensitivity GNSS (HSGNSS) receivers with block processing techniques are often used, however, the Doppler quality of such receivers is relatively poor due to multipath, fading and signal attenuation. This often limits the benefits of integrating HSGNSS Doppler with DR. This paper investigates the benefits of using Doppler measurements from a novel direct vector HSGNSS receiver with pedestrian dead-reckoning (PDR) for indoor navigation. An indoor signal and multipath model is introduced which explains how conventional HSGNSS Doppler measurements are affected by indoor multipath. Velocity and Doppler estimated by using direct vector receivers are introduced and discussed. Real experimental data is processed and analyzed to assess the veracity of proposed method. It is shown when integrating HSGNSS Doppler with PDR algorithm, the proposed direct vector method are more helpful than conventional block processing method for the indoor environments considered herein. PMID:23539033

  14. Use of high sensitivity GNSS receiver Doppler measurements for indoor pedestrian dead reckoning.

    PubMed

    He, Zhe; Renaudin, Valérie; Petovello, Mark G; Lachapelle, Gérard

    2013-01-01

    Dead-reckoning (DR) algorithms, which use self-contained inertial sensors combined with gait analysis, have proven to be effective for pedestrian navigation purposes. In such DR systems, the primary error is often due to accumulated heading drifts. By tightly integrating global navigation satellite system (GNSS) Doppler measurements with DR, such accumulated heading errors can usually be accurately compensated. Under weak signal conditions, high sensitivity GNSS (HSGNSS) receivers with block processing techniques are often used, however, the Doppler quality of such receivers is relatively poor due to multipath, fading and signal attenuation. This often limits the benefits of integrating HSGNSS Doppler with DR. This paper investigates the benefits of using Doppler measurements from a novel direct vector HSGNSS receiver with pedestrian dead-reckoning (PDR) for indoor navigation. An indoor signal and multipath model is introduced which explains how conventional HSGNSS Doppler measurements are affected by indoor multipath. Velocity and Doppler estimated by using direct vector receivers are introduced and discussed. Real experimental data is processed and analyzed to assess the veracity of proposed method. It is shown when integrating HSGNSS Doppler with PDR algorithm, the proposed direct vector method are more helpful than conventional block processing method for the indoor environments considered herein. PMID:23539033

  15. Driver compliance with stop signs at pedestrian crosswalks on a university campus.

    PubMed

    DeVeauuse, N; Kim, K; Peek-Asa, C; McArthur, D; Kraus, J

    1999-05-01

    Pedestrians on college campuses interact continuously with various motorized vehicles. Rates of compliance with stop signs at pedestrian crosswalks and noncomplying vehicles were monitored in spring 1996 on a large urban campus. The number of pedestrians, pedestrian clearance, type of vehicle, hour of day, and day of week were monitored at 3 pedestrian crosswalks. The overall compliance rate for stop signs was 22.8 per 100 vehicles, ranging from 1.4 per 100 for bicycles to 46.2 per 100 for commuter vans. Compliance increased to 53 per 100 vehicles when pedestrians were present in the crosswalk. Several differences in compliance rates were found among the observation sites. Lowest compliance was observed for bicycles and motorcycles. Pedestrians on this and other college campuses risk injuries because of violations of pedestrian right-of-way laws. The problem calls for appreciable educational efforts by college health personnel. PMID:10368561

  16. Choosing between stairs and escalators in China: The impact of location, height and pedestrian volume

    PubMed Central

    Zacharias, John; Tang, Boshen

    2015-01-01

    Objective This research examines whether Beijing residents are more or less likely than Montréal residents to avoid stair climbing, by replicating a study in Montréal, Canada that measured the impacts of distance between stairs and escalator, height between floors and pedestrian volume on stair climbing rate. Method 15 stairways, 14 up-escalators and 13 down-escalators were selected in 13 publicly accessible settings in Beijing. Distance between the bottom or top of nearest stair and escalator combinations varied from 2.1 m to 114.1 m with height between floors varying from 3.3 m to 21.7 m. Simultaneous counts were conducted on stair and escalator pairs, for a total of 37,081 counted individuals. Results In the ascent model, pedestrian volume accounted for 16.3% of variance in stair climbing, 16.4% when height was added and 45.1% when distance was added. In the descent model, 40.9% of variance was explained by pedestrian volume, 41.5% when height was added and 45.5% when distance was added. Conclusion Separating stairs and escalator is effective in increasing stair climbing in Beijing, accounting for 29% of the variance in stair climbing, compared with 43% in Montreal. As in the Montreal case, distance has less effect on stair use rate when descending. Overall, 25.4% of Beijingers opted for stairs when ascending compared with 20.3% of Montrealers, and for descending 32.8% and 31.1% respectively. PMID:26844113

  17. An Indoor Pedestrian Positioning Method Using HMM with a Fuzzy Pattern Recognition Algorithm in a WLAN Fingerprint System.

    PubMed

    Ni, Yepeng; Liu, Jianbo; Liu, Shan; Bai, Yaxin

    2016-01-01

    With the rapid development of smartphones and wireless networks, indoor location-based services have become more and more prevalent. Due to the sophisticated propagation of radio signals, the Received Signal Strength Indicator (RSSI) shows a significant variation during pedestrian walking, which introduces critical errors in deterministic indoor positioning. To solve this problem, we present a novel method to improve the indoor pedestrian positioning accuracy by embedding a fuzzy pattern recognition algorithm into a Hidden Markov Model. The fuzzy pattern recognition algorithm follows the rule that the RSSI fading has a positive correlation to the distance between the measuring point and the AP location even during a dynamic positioning measurement. Through this algorithm, we use the RSSI variation trend to replace the specific RSSI value to achieve a fuzzy positioning. The transition probability of the Hidden Markov Model is trained by the fuzzy pattern recognition algorithm with pedestrian trajectories. Using the Viterbi algorithm with the trained model, we can obtain a set of hidden location states. In our experiments, we demonstrate that, compared with the deterministic pattern matching algorithm, our method can greatly improve the positioning accuracy and shows robust environmental adaptability. PMID:27618053

  18. Pedestrian Detection Using Gradient Local Binary Patterns

    NASA Astrophysics Data System (ADS)

    Jiang, Ning; Xu, Jiu; Goto, Satoshi

    In recent years, local pattern based features have attracted increasing interest in object detection and recognition systems. Local Binary Pattern (LBP) feature is widely used in texture classification and face detection. But the original definition of LBP is not suitable for human detection. In this paper, we propose a novel feature named gradient local binary patterns (GLBP) for human detection. In this feature, original 256 local binary patterns are reduced to 56 patterns. These 56 patterns named uniform patterns are used for generating a 56-bin histogram. And gradient value of each pixel is set as the weight which is always same in LBP based features in histogram calculation to computing the values in 56 bins for histogram. Experiments are performed on INRIA dataset, which shows the proposal GLBP feature is discriminative than histogram of orientated gradient (HOG), Semantic Local Binary Patterns (S-LBP) and histogram of template (HOT). In our experiments, the window size is fixed. That means the performance can be improved by boosting methods. And the computation of GLBP feature is parallel, which make it easy for hardware acceleration. These factors make GLBP feature possible for real-time pedestrian detection.

  19. Pedestrian detection from thermal images: A sparse representation based approach

    NASA Astrophysics Data System (ADS)

    Qi, Bin; John, Vijay; Liu, Zheng; Mita, Seiichi

    2016-05-01

    Pedestrian detection, a key technology in computer vision, plays a paramount role in the applications of advanced driver assistant systems (ADASs) and autonomous vehicles. The objective of pedestrian detection is to identify and locate people in a dynamic environment so that accidents can be avoided. With significant variations introduced by illumination, occlusion, articulated pose, and complex background, pedestrian detection is a challenging task for visual perception. Different from visible images, thermal images are captured and presented with intensity maps based objects' emissivity, and thus have an enhanced spectral range to make human beings perceptible from the cool background. In this study, a sparse representation based approach is proposed for pedestrian detection from thermal images. We first adopted the histogram of sparse code to represent image features and then detect pedestrian with the extracted features in an unimodal and a multimodal framework respectively. In the unimodal framework, two types of dictionaries, i.e. joint dictionary and individual dictionary, are built by learning from prepared training samples. In the multimodal framework, a weighted fusion scheme is proposed to further highlight the contributions from features with higher separability. To validate the proposed approach, experiments were conducted to compare with three widely used features: Haar wavelets (HWs), histogram of oriented gradients (HOG), and histogram of phase congruency (HPC) as well as two classification methods, i.e. AdaBoost and support vector machine (SVM). Experimental results on a publicly available data set demonstrate the superiority of the proposed approach.

  20. Review of safety and mobility issues among older pedestrians.

    PubMed

    Tournier, Isabelle; Dommes, Aurélie; Cavallo, Viola

    2016-06-01

    Although old people make up an extremely vulnerable road-user group, older pedestrians' difficulties have been studied less extensively than those of older drivers, and more knowledge of this issue is still required. The present paper reviews current knowledge of older-adult problems with the main components of pedestrian activity, i.e., walking and obstacle negotiation, wayfinding, and road crossing. Compared to younger ones, old pedestrians exhibit declining walking skills, with a walking speed decrease, less stable balance, less efficient wayfinding strategies, and a greater number of unsafe road crossing behaviors. These difficulties are linked to age-related changes in sensorial, cognitive, physical, and self-perception abilities. It is now known that visual impairment, physical frailty, and attention deficits have a major negative impact on older pedestrians' safety and mobility, whereas the roles of self-evaluation and self-regulation are still poorly understood. All these elements must be taken into consideration, not only in developing effective safety interventions targeting older pedestrians, but also in designing roads and cars. Recent initiatives are presented here and some recommendations are proposed. PMID:26950033

  1. A heterogeneous lattice gas model for simulating pedestrian evacuation

    NASA Astrophysics Data System (ADS)

    Guo, Xiwei; Chen, Jianqiao; Zheng, Yaochen; Wei, Junhong

    2012-02-01

    Based on the cellular automata method (CA model) and the mobile lattice gas model (MLG model), we have developed a heterogeneous lattice gas model for simulating pedestrian evacuation processes in an emergency. A local population density concept is introduced first. The update rule in the new model depends on the local population density and the exit crowded degree factor. The drift D, which is one of the key parameters influencing the evacuation process, is allowed to change according to the local population density of the pedestrians. Interactions including attraction, repulsion, and friction between every two pedestrians and those between a pedestrian and the building wall are described by a nonlinear function of the corresponding distance, and the repulsion forces increase sharply as the distances get small. A critical force of injury is introduced into the model, and its effects on the evacuation process are investigated. The model proposed has heterogeneous features as compared to the MLG model or the basic CA model. Numerical examples show that the model proposed can capture the basic features of pedestrian evacuation, such as clogging and arching phenomena.

  2. Macroscopic spatial analysis of pedestrian and bicycle crashes.

    PubMed

    Siddiqui, Chowdhury; Abdel-Aty, Mohamed; Choi, Keechoo

    2012-03-01

    This study investigates the effect of spatial correlation using a Bayesian spatial framework to model pedestrian and bicycle crashes in Traffic Analysis Zones (TAZs). Aggregate models for pedestrian and bicycle crashes were estimated as a function of variables related to roadway characteristics, and various demographic and socio-economic factors. It was found that significant differences were present between the predictor sets for pedestrian and bicycle crashes. The Bayesian Poisson-lognormal model accounting for spatial correlation for pedestrian crashes in the TAZs of the study counties retained nine variables significantly different from zero at 95% Bayesian credible interval. These variables were - total roadway length with 35 mph posted speed limit, total number of intersections per TAZ, median household income, total number of dwelling units, log of population per square mile of a TAZ, percentage of households with non-retired workers but zero auto, percentage of households with non-retired workers and one auto, long term parking cost, and log of total number of employment in a TAZ. A separate distinct set of predictors were found for the bicycle crash model. In all cases the Bayesian models with spatial correlation performed better than the models that did not account for spatial correlation among TAZs. This finding implies that spatial correlation should be considered while modeling pedestrian and bicycle crashes at the aggregate or macro-level. PMID:22269522

  3. Evacuation of Pedestrians with Two Motion Modes for Panic System.

    PubMed

    Zou, You; Xie, Jiarong; Wang, Binghong

    2016-01-01

    In this paper, we have captured an underlying mechanism of emergence of collective panic in pedestrian evacuations by using a modification of the lattice-gas model. We classify the motion of pedestrians into two modes according to their moods. One is gentle (mode I), the other is flustered (mode II). First, to research the cause for crowd, we fix the motion modes of pedestrians and increase the proportion of pedestrians with motion mode II (ρII). The simulation results show that the pedestrians with motion mode II are lack of evacuation efficiency and cause more casualties. Further, we use the SIS (susceptible-infective-susceptible) model to describe the spreading of the panic mood. The system can be in the high-mix state when the infection probability λ is greater than a fuzzy threshold. In addition, the distances S from wounded people to the exit are researched, the number of wounded people gets maximum at the internal S = 5∼10, which is independent of ρII and λ. This research can help us to understand and prevent the emergence of collective panic and reduce wounds in the real evacuation. PMID:27055024

  4. Evacuation of Pedestrians with Two Motion Modes for Panic System

    PubMed Central

    Zou, You; Xie, Jiarong; Wang, Binghong

    2016-01-01

    In this paper, we have captured an underlying mechanism of emergence of collective panic in pedestrian evacuations by using a modification of the lattice-gas model. We classify the motion of pedestrians into two modes according to their moods. One is gentle (mode I), the other is flustered (mode II). First, to research the cause for crowd, we fix the motion modes of pedestrians and increase the proportion of pedestrians with motion mode II (ρII). The simulation results show that the pedestrians with motion mode II are lack of evacuation efficiency and cause more casualties. Further, we use the SIS (susceptible-infective-susceptible) model to describe the spreading of the panic mood. The system can be in the high-mix state when the infection probability λ is greater than a fuzzy threshold. In addition, the distances S from wounded people to the exit are researched, the number of wounded people gets maximum at the internal S = 5 ∼ 10, which is independent of ρII and λ. This research can help us to understand and prevent the emergence of collective panic and reduce wounds in the real evacuation. PMID:27055024

  5. A new collision avoidance model for pedestrian dynamics

    NASA Astrophysics Data System (ADS)

    Wang, Qian-Ling; Chen, Yao; Dong, Hai-Rong; Zhou, Min; Ning, Bin

    2015-03-01

    The pedestrians can only avoid collisions passively under the action of forces during simulations using the social force model, which may lead to unnatural behaviors. This paper proposes an optimization-based model for the avoidance of collisions, where the social repulsive force is removed in favor of a search for the quickest path to destination in the pedestrian’s vision field. In this way, the behaviors of pedestrians are governed by changing their desired walking direction and desired speed. By combining the critical factors of pedestrian movement, such as positions of the exit and obstacles and velocities of the neighbors, the choice of desired velocity has been rendered to a discrete optimization problem. Therefore, it is the self-driven force that leads pedestrians to a free path rather than the repulsive force, which means the pedestrians can actively avoid collisions. The new model is verified by comparing with the fundamental diagram and actual data. The simulation results of individual avoidance trajectories and crowd avoidance behaviors demonstrate the reasonability of the proposed model. Project supported by the National Natural Science Foundation of China (Grant Nos. 61233001 and 61322307) and the Fundamental Research Funds for Central Universities of China (Grant No. 2013JBZ007).

  6. Asymmetric effect on single-file dense pedestrian flow

    NASA Astrophysics Data System (ADS)

    Kuang, Hua; Cai, Mei-Jing; Li, Xing-Li; Song, Tao

    2015-11-01

    In this paper, an extended optimal velocity model is proposed to simulate single-file dense pedestrian flow by considering asymmetric interaction (i.e. attractive force and repulsive force), which depends on the different distances between pedestrians. The stability condition of this model is obtained by using the linear stability theory. The phase diagram comparison and analysis show that asymmetric effect plays an important role in strengthening the stabilization of system. The modified Korteweg-de Vries (mKdV) equation near the critical point is derived by applying the reductive perturbation method. The pedestrian jam could be described by the kink-antikink soliton solution for the mKdV equation. From the simulation of space-time evolution of the pedestrians distance, it can be found that the asymmetric interaction is more efficient compared to the symmetric interaction in suppressing the pedestrian jam. Furthermore, the simulation results are consistent with the theoretical analysis as well as reproduce experimental phenomena better.

  7. Identification of Child Pedestrian Training Objectives: The Role of Task Analysis and Empirical Research.

    ERIC Educational Resources Information Center

    van der Molen, Hugo H.

    1984-01-01

    Describes a study designed to demonstrate that child pedestrian training objectives may be identified systematically through various task analysis methods, making use of different types of empirical information. Early approaches to analysis of pedestrian tasks are reviewed, and an outline of the Traffic Research Centre's pedestrian task analysis…

  8. Pedestrian Choice Behavior at Shopping Mall Intersections in China and the United States

    ERIC Educational Resources Information Center

    Bitgood, Stephen; Davey, Gareth; Huang, Xiaoyi; Fung, Holly

    2013-01-01

    Pedestrian navigation through public spaces reflects the nature of interaction between behavior and environment. This study compared pedestrian choice behavior at shopping mall intersections in China and the United States. The study found that in both countries (a) pedestrians chose movement patterns that involved the fewest steps and (b) there…

  9. Domain Adaptation for Pedestrian Detection Based on Prediction Consistency

    PubMed Central

    Huan-ling, Tang; Zhi-yong, An

    2014-01-01

    Pedestrian detection is an active area of research in computer vision. It remains a quite challenging problem in many applications where many factors cause a mismatch between source dataset used to train the pedestrian detector and samples in the target scene. In this paper, we propose a novel domain adaptation model for merging plentiful source domain samples with scared target domain samples to create a scene-specific pedestrian detector that performs as well as rich target domain simples are present. Our approach combines the boosting-based learning algorithm with an entropy-based transferability, which is derived from the prediction consistency with the source classifications, to selectively choose the samples showing positive transferability in source domains to the target domain. Experimental results show that our approach can improve the detection rate, especially with the insufficient labeled data in target scene. PMID:25013850

  10. Pedestrian Navigation Using Foot-Mounted Inertial Sensor and LIDAR

    PubMed Central

    Pham, Duy Duong; Suh, Young Soo

    2016-01-01

    Foot-mounted inertial sensors can be used for indoor pedestrian navigation. In this paper, to improve the accuracy of pedestrian location, we propose a method using a distance sensor (LIDAR) in addition to an inertial measurement unit (IMU). The distance sensor is a time of flight range finder with 30 m measurement range (at 33.33 Hz). Using a distance sensor, walls on corridors are automatically detected. The detected walls are used to correct the heading of the pedestrian path. Through experiments, it is shown that the accuracy of the heading is significantly improved using the proposed algorithm. Furthermore, the system is shown to work robustly in indoor environments with many doors and passing people. PMID:26797619

  11. Pedestrian dead reckoning for MARG navigation using a smartphone

    NASA Astrophysics Data System (ADS)

    Tian, Zengshan; Zhang, Yuan; Zhou, Mu; Liu, Yu

    2014-12-01

    The demand for navigating pedestrian by using a hand-held mobile device increased remarkably over the past few years, especially in GPS-denied scenario. We propose a new pedestrian dead reckoning (PDR)-based navigation algorithm by using magnetic, angular rate, and gravity (MARG) sensors which are equipped in existing commercial smartphone. Our proposed navigation algorithm consists of step detection, stride length estimation, and heading estimation. To eliminate the gauge step errors of the random bouncing motions, we designed a reliable algorithm for step detection. We developed a BP neural network-based stride length estimation algorithm to apply to different users. In response to the challenge of magnetic disturbance, a quaternion-based extended Kalman filter (EKF) is introduced to determine the user's heading direction for each step. The performance of our proposed pedestrian navigation algorithm is verified by using a smartphone in providing accurate, reliable, and continuous location tracking services.

  12. Guiding Blind Pedestrians with a Personal Navigation System

    NASA Astrophysics Data System (ADS)

    Dodson, A. H.; Moon, G. V.; Moore, T.; Jones, D.

    With the assistance provided by the white cane or guide dog, most blind pedestrians can find their way to known destinations along familiar routes. Finding new or known destinations along unfamiliar routes is more challenging. Before such a journey is attempted, detailed instructions must be acquired. The difficulty of obtaining and then reliably following such instructions deters many blind pedestrians from travelling alone in unknown areas. This paper demonstrates a technological approach, by way of field trials, that supplements the existing aids and eliminates the need for sighted guides. The approach has the potential to offer greater independence to the blind person. The investigation suggests that the methodology used in personal navigation systems for the sighted is sub-optimal for guiding the blind pedestrian. Suitable extensions are introduced, and the results show the proposed methodology is efficient for guiding the blind individual to unknown destinations in the chosen field trial environment.

  13. Pedestrian Navigation Using Foot-Mounted Inertial Sensor and LIDAR.

    PubMed

    Pham, Duy Duong; Suh, Young Soo

    2016-01-01

    Foot-mounted inertial sensors can be used for indoor pedestrian navigation. In this paper, to improve the accuracy of pedestrian location, we propose a method using a distance sensor (LIDAR) in addition to an inertial measurement unit (IMU). The distance sensor is a time of flight range finder with 30 m measurement range (at 33.33 Hz). Using a distance sensor, walls on corridors are automatically detected. The detected walls are used to correct the heading of the pedestrian path. Through experiments, it is shown that the accuracy of the heading is significantly improved using the proposed algorithm. Furthermore, the system is shown to work robustly in indoor environments with many doors and passing people. PMID:26797619

  14. Pedestrian worker fatalities in workplace locations, Australia, 2000-2010.

    PubMed

    Kitching, Fiona; Jones, Christopher B; Ibrahim, Joseph E; Ozanne-Smith, Joan

    2014-01-01

    Pedestrian deaths of workers in Australian workplaces (1 July 2000-31 December 2010) are described using coronial and safety authority fatality databases. One hundred and fifteen deaths were identified, with the majority male (93%) and aged over 50 years (59%). Four industries predominated (85% of deaths): Agriculture, Forestry and Fishing (31%), Construction (29%), Transport, Postal and Warehousing (16%) and Manufacturing (10%). Similarly, three occupations dominated: Farmers (28%), Labourers (27%) and Machinery Operators and Drivers (25%). Common circumstantial factors (reversing machines or vehicles, driver also the pedestrian, driver's vision impeded and working accompanied) occurred in the Construction, Transport and Manufacturing industries, providing collaborative opportunities for prevention. Deaths occurring in the Agriculture industry showed different circumstantial factors, likely needing different solutions. While some effective countermeasures are known, workplace pedestrian fatalities continue to occur. Prevention strategies are needed to share known information across industries and to produce data enhancements and new knowledge. PMID:23656178

  15. Analysis of fatal train-pedestrian collisions in metropolitan Chicago 2004-2012.

    PubMed

    Savage, Ian

    2016-01-01

    The paper analyzes spatial and temporal data on fatal train-pedestrian collisions in the Chicago metropolitan area between 2004 and 2012. In comparing different municipalities within the region, the density of grade crossings and stations is found to increase the frequency of unintentional deaths. However, unintentional deaths do not increase with train volume suggesting that pedestrians may exercise more care around busier lines. The distribution of apparent intentional deaths is less strongly related to the density of crossings and stations suggesting that those intending self-harm will seek out a point of access. Apparent intentional deaths are more prevalent on lines with frequent passenger trains, and in municipalities with higher incomes and lower population densities. While most of the apparent intentional deaths (about 70%) are not associated with any copycat activities, the dataset contains possible clusters of intentional deaths that are proximate in both time and space. There was also a highly publicized suicide that led to a 95% increase in apparent intentional deaths throughout the region in the 18 weeks following the incident. PMID:26595177

  16. Safety education of pedestrians for injury prevention: a systematic review of randomised controlled trials

    PubMed Central

    Duperrex, Olivier; Bunn, Frances; Roberts, Ian

    2002-01-01

    Objectives To quantify the effectiveness of safety education of pedestrians. Design Systematic review of randomised controlled trials of safety education programmes for pedestrians of all ages. Main outcome measures Effect of safety education on pedestrians' injuries, behaviour, attitude, and knowledge and on pedestrian-motor vehicle collisions. Quality of trials: methods of randomisation; and numbers lost to follow up Results We identified 15 randomised controlled trials of safety education programmes for pedestrians. Fourteen trials targeted children, and one targeted institutionalised adults. None assessed the effect of safety education on the occurrence of pedestrian injury, but six trials assessed its effect on behaviour. The effect of pedestrian education on behaviour varied considerably across studies and outcomes. Conclusions Pedestrian safety education can change observed road crossing behaviour, but whether this reduces the risk of pedestrian injury in road traffic crashes is unknown. There is a lack of good evidence of effectiveness of safety education for adult pedestrians, specially elderly people. None of the trials was conducted in low or middle income countries. What is already known on this topicRoad traffic crashes are a leading cause of death and disablement, and pedestrians are particularly vulnerable road usersSeveral organisations strongly recommend road safety educationAs resources are limited, a key question concerns the relative effectiveness of different prevention strategies, including road safety education of pedestriansWhat this study addsThis systematic review showed safety education for pedestrians could improve children's knowledge and change their observed road crossing behaviourHowever, effects on pedestrian injury were unknownThere is a lack of good evidence of effectiveness of safety education for adult pedestrians, especially elderly people, and in low and middle income countries PMID:12003885

  17. Robust Pedestrian Detection by Combining Visible and Thermal Infrared Cameras

    PubMed Central

    Lee, Ji Hoon; Choi, Jong-Suk; Jeon, Eun Som; Kim, Yeong Gon; Thanh Le, Toan; Shin, Kwang Yong; Lee, Hyeon Chang; Park, Kang Ryoung

    2015-01-01

    With the development of intelligent surveillance systems, the need for accurate detection of pedestrians by cameras has increased. However, most of the previous studies use a single camera system, either a visible light or thermal camera, and their performances are affected by various factors such as shadow, illumination change, occlusion, and higher background temperatures. To overcome these problems, we propose a new method of detecting pedestrians using a dual camera system that combines visible light and thermal cameras, which are robust in various outdoor environments such as mornings, afternoons, night and rainy days. Our research is novel, compared to previous works, in the following four ways: First, we implement the dual camera system where the axes of visible light and thermal cameras are parallel in the horizontal direction. We obtain a geometric transform matrix that represents the relationship between these two camera axes. Second, two background images for visible light and thermal cameras are adaptively updated based on the pixel difference between an input thermal and pre-stored thermal background images. Third, by background subtraction of thermal image considering the temperature characteristics of background and size filtering with morphological operation, the candidates from whole image (CWI) in the thermal image is obtained. The positions of CWI (obtained by background subtraction and the procedures of shadow removal, morphological operation, size filtering, and filtering of the ratio of height to width) in the visible light image are projected on those in the thermal image by using the geometric transform matrix, and the searching regions for pedestrians are defined in the thermal image. Fourth, within these searching regions, the candidates from the searching image region (CSI) of pedestrians in the thermal image are detected. The final areas of pedestrians are located by combining the detected positions of the CWI and CSI of the thermal

  18. Reserve capacity and exit choosing in pedestrian evacuation dynamics

    NASA Astrophysics Data System (ADS)

    Zhao, Hui; Gao, Ziyou

    2010-03-01

    A modified cellular automata model is proposed to simulate the pedestrian evacuation behavior in a room with multiple exits by considering the reserve capacity of the exit. The main idea is motivated by the original concept of minority game, which means less congested exits may be preferentially chosen together with the floor fields. The model outperforms previous ones under the condition in which pedestrians are distributed heterogeneously. Simulation results show that wise exit choosing with the consideration of reserve capacity may reduce the evacuation time apparently, which is more realistic. Furthermore, the impacts of the room geometry and parameter settings are investigated extensively.

  19. Pedestrian Evacuation Analysis for Tsunami Hazards

    NASA Astrophysics Data System (ADS)

    Jones, J. M.; Ng, P.; Wood, N. J.

    2014-12-01

    Recent catastrophic tsunamis in the last decade, as well as the 50th anniversary of the 1964 Alaskan event, have heightened awareness of the threats these natural hazards present to large and increasing coastal populations. For communities located close to the earthquake epicenter that generated the tsunami, strong shaking may also cause significant infrastructure damage, impacting the road network and hampering evacuation. There may also be insufficient time between the earthquake and first wave arrival to rely on a coordinated evacuation, leaving at-risk populations to self-evacuate on foot and across the landscape. Emergency managers evaluating these coastal risks need tools to assess the evacuation potential of low-lying areas in order to discuss mitigation options, which may include vertical evacuation structures to provide local safe havens in vulnerable communities. The U.S. Geological Survey has developed the Pedestrian Evacuation Analyst software tool for use by researchers and emergency managers to assist in the assessment of a community's evacuation potential by modeling travel times across the landscape and producing both maps of travel times and charts of population counts with corresponding times. The tool uses an anisotropic (directionally dependent) least cost distance model to estimate evacuation potential and allows for the variation of travel speed to measure its effect on travel time. The effectiveness of vertical evacuation structures on evacuation time can also be evaluated and compared with metrics such as travel time maps showing each structure in place and graphs displaying the percentage change in population exposure for each structure against the baseline. Using the tool, travel time maps and at-risk population counts have been generated for some coastal communities of the U.S. Pacific Northwest and Alaska. The tool can also be used to provide valuable decision support for tsunami vertical evacuation siting.

  20. Modelling pedestrian travel time and the design of facilities: a queuing approach.

    PubMed

    Rahman, Khalidur; Ghani, Noraida Abdul; Kamil, Anton Abdulbasah; Mustafa, Adli; Kabir Chowdhury, Md Ahmed

    2013-01-01

    Pedestrian movements are the consequence of several complex and stochastic facts. The modelling of pedestrian movements and the ability to predict the travel time are useful for evaluating the performance of a pedestrian facility. However, only a few studies can be found that incorporate the design of the facility, local pedestrian body dimensions, the delay experienced by the pedestrians, and level of service to the pedestrian movements. In this paper, a queuing based analytical model is developed as a function of relevant determinants and functional factors to predict the travel time on pedestrian facilities. The model can be used to assess the overall serving rate or performance of a facility layout and correlate it to the level of service that is possible to provide the pedestrians. It has also the ability to provide a clear suggestion on the designing and sizing of pedestrian facilities. The model is empirically validated and is found to be a robust tool to understand how well a particular walking facility makes possible comfort and convenient pedestrian movements. The sensitivity analysis is also performed to see the impact of some crucial parameters of the developed model on the performance of pedestrian facilities. PMID:23691055

  1. Modelling Pedestrian Travel Time and the Design of Facilities: A Queuing Approach

    PubMed Central

    Rahman, Khalidur; Abdul Ghani, Noraida; Abdulbasah Kamil, Anton; Mustafa, Adli; Kabir Chowdhury, Md. Ahmed

    2013-01-01

    Pedestrian movements are the consequence of several complex and stochastic facts. The modelling of pedestrian movements and the ability to predict the travel time are useful for evaluating the performance of a pedestrian facility. However, only a few studies can be found that incorporate the design of the facility, local pedestrian body dimensions, the delay experienced by the pedestrians, and level of service to the pedestrian movements. In this paper, a queuing based analytical model is developed as a function of relevant determinants and functional factors to predict the travel time on pedestrian facilities. The model can be used to assess the overall serving rate or performance of a facility layout and correlate it to the level of service that is possible to provide the pedestrians. It has also the ability to provide a clear suggestion on the designing and sizing of pedestrian facilities. The model is empirically validated and is found to be a robust tool to understand how well a particular walking facility makes possible comfort and convenient pedestrian movements. The sensitivity analysis is also performed to see the impact of some crucial parameters of the developed model on the performance of pedestrian facilities. PMID:23691055

  2. Intensity variation function and template matching-based pedestrian tracking in infrared imagery with occlusion detection and recovery

    NASA Astrophysics Data System (ADS)

    Lamberti, Fabrizio; Santomo, Rocco; Sanna, Andrea; Montuschi, Paolo

    2015-03-01

    Robustly and efficiently tracking pedestrians in the infrared spectrum is a crucial requirement for a number of applications. At the same time, it is also particularly critical due to both the peculiarities of infrared images and pedestrian targets. In fact, low resolutions and high signal-to-noise ratios combined with extremely variable target signatures, chaotic trajectories, and frequent occlusions have forced researchers to develop ever more complex strategies characterized by a neat trade-off between tracking accuracy and computational complexity. Thus, most of the existing techniques might not be capable of ensuring real-time performances with a suitable degree of robustness, especially on limited-resource hardware used, e.g., in automotive or security scenarios. We present a technique that extends an extremely efficient tracking method originally tailored to targets that exhibit a clear and stable hot spot to allow it to deal with pedestrian targets by reusing its core components and integrating an occlusion detection and recovery mechanism. Experimental results obtained on public datasets confirmed that the devised method is able to obtain a robustness that is superior to that of other common approaches by maintaining the high tracking speed of the reference method.

  3. Constructal law: Pleasure, golden ratio, animal locomotion and the design of pedestrian evacuation. Comment on “The emergence of design in pedestrian dynamics: Locomotion, self-organization, walking paths and the constructal law” by A. Miguel

    NASA Astrophysics Data System (ADS)

    Bejan, Adrian

    2013-06-01

    Pedestrian flow belongs to the design of animal movement, covered by the constructal law of design (animate, inanimate) in nature. Walking and running, like water waves, are forms of falling-forward movement, with speeds in accord with the constructal law. Travel on an area is a balanced combination of “long and fast and short and slow”. Bodies moving on an area are a balanced combination of “few large and many small”. Comfort, beauty (golden ratio) and pleasure guide human movement to greater access, in accord with the constructal law.

  4. Selfishness- and Selflessness-based models of pedestrian room evacuation

    NASA Astrophysics Data System (ADS)

    Song, Xiao; Ma, Liang; Ma, Yaofei; Yang, Chen; Ji, Hang

    2016-04-01

    Some pedestrian evacuation studies have employed game strategy to deal with moving conflicts involving two or three pedestrians. However, most of these have simply presented game strategies for pedestrians without analyzing the reasons why they choose to defect or cooperate. We believe that selfish and selfless behaviors are two main factors that should be considered in evacuation. In addition to these behaviors, human emotions such as sympathy and behaviors such as vying were also taken into account to investigate their impacts on pedestrians' strategies. Moreover, an essential objective factor, the building design factor of door width was tested and analyzed. Experimental results showed that the sense of self leads to more defectors and a longer evacuation time. However, sympathy does some good, leading to more cooperators and a shorter evacuation time. Moreover, the exit door width is an essential factor of the evacuation efficiency. When the width was less than 6 cells in a rectangular room with a size greater than 50 × 50, the evacuation time greatly decreased when the width increased. However, this effect was less obvious when the width increased.

  5. Pedestrian Crossings - USMES Teacher Resource Book. Fifth Edition. Trial Edition.

    ERIC Educational Resources Information Center

    Keskulla, Jean

    This Unified Sciences and Mathematics for Elementary Schools (USMES) unit challenges students to improve the safety and convenience of a pedestrian crossing near a school. The challenge is general enough to apply to many problem-solving situations in mathematics, science, social science, and language arts at any elementary school level (grades…

  6. 7 CFR 501.11 - Mobile equipment and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Mobile equipment and pedestrian traffic. 501.11 Section 501.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON U.S. MEAT ANIMAL RESEARCH CENTER, CLAY CENTER,...

  7. 7 CFR 501.11 - Mobile equipment and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Mobile equipment and pedestrian traffic. 501.11 Section 501.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON U.S. MEAT ANIMAL RESEARCH CENTER, CLAY CENTER,...

  8. 7 CFR 501.11 - Mobile equipment and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Mobile equipment and pedestrian traffic. 501.11 Section 501.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON U.S. MEAT ANIMAL RESEARCH CENTER, CLAY CENTER,...

  9. 7 CFR 501.11 - Mobile equipment and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Mobile equipment and pedestrian traffic. 501.11 Section 501.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON U.S. MEAT ANIMAL RESEARCH CENTER, CLAY CENTER,...

  10. 7 CFR 501.11 - Mobile equipment and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Mobile equipment and pedestrian traffic. 501.11 Section 501.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON U.S. MEAT ANIMAL RESEARCH CENTER, CLAY CENTER,...

  11. 36 CFR 520.14 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... traffic. 520.14 Section 520.14 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND... § 520.14 Vehicular and pedestrian traffic. (a) Drivers of all vehicles in or on the premises shall drive... police and all posted traffic signs. (b) The blocking of entrances, driveways, walks, loading...

  12. Effects of a Driver Enforcement Program on Yielding to Pedestrians

    ERIC Educational Resources Information Center

    Van Houten, Ron; Malenfant, J. E. Louis

    2004-01-01

    A driver-yielding enforcement program that included decoy pedestrians, feedback flyers, written and verbal warnings, and saturation enforcement for a 2-week period was evaluated in the city of Miami Beach using a multiple baseline design. During baseline, data were collected at crosswalks along two major corridors. Treatment was introduced first…

  13. California Guide for Pedestrian Safety Education. Volumes I-III.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    This guide is designed to serve as the basis for a pedestrian safety education program for pupils in kindergarten through grade two. The basic printed materials for use in the program are provided in three volumes, each of which is intended for a different audience. Volume I, directed to school administrators and teachers, contains information for…

  14. 36 CFR 520.14 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... traffic. 520.14 Section 520.14 Parks, Forests, and Public Property SMITHSONIAN INSTITUTION RULES AND... § 520.14 Vehicular and pedestrian traffic. (a) Drivers of all vehicles in or on the premises shall drive... police and all posted traffic signs. (b) The blocking of entrances, driveways, walks, loading...

  15. 31 CFR 407.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Vehicular and pedestrian traffic. 407.12 Section 407.12 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY REGULATIONS GOVERNING CONDUCT IN THE TREASURY BUILDING AND...

  16. 31 CFR 407.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false Vehicular and pedestrian traffic. 407.12 Section 407.12 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY REGULATIONS GOVERNING CONDUCT IN THE TREASURY BUILDING AND...

  17. 31 CFR 407.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Vehicular and pedestrian traffic. 407.12 Section 407.12 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY REGULATIONS GOVERNING CONDUCT IN THE TREASURY BUILDING AND...

  18. 31 CFR 407.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Vehicular and pedestrian traffic. 407.12 Section 407.12 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY REGULATIONS GOVERNING CONDUCT IN THE TREASURY BUILDING AND...

  19. 31 CFR 407.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Vehicular and pedestrian traffic. 407.12 Section 407.12 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) SECRET SERVICE, DEPARTMENT OF THE TREASURY REGULATIONS GOVERNING CONDUCT IN THE TREASURY BUILDING AND...

  20. 31 CFR 91.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Vehicular and pedestrian traffic. 91.12 Section 91.12 Money and Finance: Treasury Regulations Relating to Money and Finance REGULATIONS GOVERNING CONDUCT IN OR ON THE BUREAU OF THE MINT BUILDINGS AND GROUNDS § 91.12 Vehicular and...

  1. Arizona Traffic Safety Education, K-8. Pedestrian Safety, Grade 2.

    ERIC Educational Resources Information Center

    Mesa Public Schools, AZ.

    One in a series designed to assist Arizona elementary and junior high school teachers in developing children's traffic safety skills, this curriculum guide contains eight lessons on pedestrian safety for use in grade 2. Introductory information provided for the teacher includes basic highway safety concepts, stressing communication methods for…

  2. 7 CFR 503.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Vehicular and pedestrian traffic. 503.12 Section 503.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.12 Vehicular and...

  3. 7 CFR 503.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Vehicular and pedestrian traffic. 503.12 Section 503.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.12 Vehicular and...

  4. 7 CFR 503.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 6 2011-01-01 2011-01-01 false Vehicular and pedestrian traffic. 503.12 Section 503.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.12 Vehicular and...

  5. 7 CFR 503.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Vehicular and pedestrian traffic. 503.12 Section 503.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.12 Vehicular and...

  6. 7 CFR 503.12 - Vehicular and pedestrian traffic.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Vehicular and pedestrian traffic. 503.12 Section 503.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL RESEARCH SERVICE, DEPARTMENT OF AGRICULTURE CONDUCT ON PLUM ISLAND ANIMAL DISEASE CENTER § 503.12 Vehicular and...

  7. Block 3. General view of the northwest pedestrian entrance of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Block 3. General view of the northwest pedestrian entrance of Block 3 demonstrating the change in grading throughout the park and the change in building materials (brick and concrete). Photograph exhibits stair walls, berms and trees - Skyline Park, 1500-1800 Arapaho Street, Denver, Denver County, CO

  8. Evaluating Three Interface Technologies in Assisting PEDESTRIANS' Spatial Knowledge Acquisition

    NASA Astrophysics Data System (ADS)

    Huang, H.; Schmidt, M.; Gartner, G.

    2012-07-01

    Recent years have seen raising interests in mobile pedestrian navigation systems. Different interface technologies can be used to communicate/convey route directions to pedestrians, such as mobile maps, voices, and augmented reality (AR). Many field experiments have been conducted to study the effectiveness of different interface technologies in guiding pedestrians to their destinations. In contrast to other field studies, this article aims at investigating the influence of different interface technologies on spatial knowledge acquisition (spatial learning). With sufficient spatial knowledge about an environment, people can still find their way when navigation systems fail (e.g. out of battery). The goal of this article is to empirically evaluate three GPS-based navigation prototypes (implementing mobile map-based, AR-based, and voice-based guidance respectively) in supporting spatial knowledge acquisition. The field test showed that in terms of spatial knowledge acquisition, the three interface technologies led to comparable poor results, which were also not significantly different from each other. This article concludes with some implications for designing mobile pedestrian navigation systems.

  9. Henry Hudson Bridge upper deck and pedestrian walkway showing parapets ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Henry Hudson Bridge upper deck and pedestrian walkway showing parapets with pipe rails. View of Inwood Hill Park in background, with a faint view of the Empire State Building amidst distant highrises at left, looking south. - Henry Hudson Parkway, Extending 11.2 miles from West 72nd Street to Bronx-Westchester border, New York County, NY

  10. Arizona Traffic Safety Education, K-3. Pedestrian Safety, Grade 3.

    ERIC Educational Resources Information Center

    Mesa Public Schools, AZ.

    One in a series designed to assist Arizona elementary and junior high school teachers in developing children's traffic safety skills, this curriculum guide contains nine lessons on pedestrian safety for use in grade 3. Introductory information provided for the teacher includes basic highway safety concepts, stressing communication methods for…

  11. 23. Old Crosscut Canal, Pedestrian Bridge Details, February 1975. See ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Old Crosscut Canal, Pedestrian Bridge Details, February 1975. See photographs AZ-21-13 and AZ-21-14 for views of the completed bridge. Source: city of Phoenix Engineering Department. - Old Crosscut Canal, North Side of Salt River, Phoenix, Maricopa County, AZ

  12. CONTEXT VIEW SHOWING JUXTAPOSITION OF MACHINE SHOP, PEDESTRIAN BRIDGE, HISTORIC ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CONTEXT VIEW SHOWING JUXTAPOSITION OF MACHINE SHOP, PEDESTRIAN BRIDGE, HISTORIC RAIL BED, LUNCH/SHOWER BUILDING, AND HULETTS. LOOKING NORTHEAST. - Pennsylvania Railway Ore Dock, Lake Erie at Whiskey Island, approximately 1.5 miles west of Public Square, Cleveland, Cuyahoga County, OH

  13. Optimal Design of HGV Front Structure for Pedestrian Safety

    NASA Astrophysics Data System (ADS)

    Ramli, Faiz Redza; Yamazaki, Koetsu

    This paper addresses a pedestrian safety design of front structure of Heavy Goods Vehicle (HGV) by two concepts; firstly by equipping a lower bumper stiffener structure under the front bumper and secondly by putting an airbag in front of the HGV front panel. In this study, HGV-pedestrian collision accident was simulated by the crash analysis solver MADYMO environment, where the HGV model with the speed of 20 km/h was collided with an adult male and with an adult female pedestrian, respectively. The bumper and lower bumper stiffener were varied their positions, while the airbag was adjusted the vent hole size and the position of airbag in front of front panel vertically. The pedestrian injuries that can be sustained during the simulation impact were limited at the critical body parts of head, chest, upper leg; an injury criteria of Head Injury Criterion (HIC), Thorax Cumulative 3ms Acceleration (C3ms) and peak loads of femur, respectively. Because of various parameters and constraints of initial conditions and injury thresholds, a multi-objective optimization design problem considered these main injury criterion is solved in order to achieve the best solution for this study. The results of optimized design parameters for each cases and conditions were obtained and the possibilities of the proposed concept were discussed.

  14. Using Interactive Multimedia to Teach Pedestrian Safety: An Exploratory Study

    ERIC Educational Resources Information Center

    Glang, Ann; Noell, John; Ary, Dennis; Swartz, Lynne

    2005-01-01

    Objectives: To evaluate an interactive multimedia (IMM) program that teaches young children safe pedestrian skills. Methods: The program uses IMM (animation and video) to teach children critical skills for crossing streets safely. A computer-delivered video assessment and a real-life street simulation were used to measure the effectiveness of the…

  15. Main characteristics of train-pedestrian fatalities on Finnish railroads.

    PubMed

    Silla, Anne; Luoma, Juha

    2012-03-01

    The aim of this study was to describe the frequency of fatalities, timing of collisions and characteristics of persons killed in train-pedestrian collisions on Finnish railways during 2005-2009. In addition, the Finnish results were compared with those collected in Sweden. The Finnish data were combined from five different sources. The results showed that 311 pedestrians were killed in train-pedestrian collisions, including 264 suicides, 35 accidents and 12 unclassified events. For each event type, most of the victims were male. Most suicide victims were in the 20-29 year age group and on average younger than people who chose some other form of suicide. About half of all victims were intoxicated by alcohol, medicines and/or drugs. Both suicides and accidents occurred most often at the end of the week but no specific peak for time of year was found. Suicides occurred most frequently from afternoon to night and accidents during the rush hours. Most train-pedestrian fatalities happened in densely populated areas. In conclusion, the effective prevention of railway suicides and accidents calls for a systems approach involving effective measures introduced by authorities responsible for urban planning, railways, education and public health. PMID:22269485

  16. Pedestrian Safety Training Curriculum for Persons with Developmental Disabilities.

    ERIC Educational Resources Information Center

    Illinois State Office of the Secretary of State, Springfield.

    This manual provides a suggested curriculum, intended for use in the natural environment, for individualized instruction on street travel skills for adults with developmental disabilities. Suggestions are given for instruction in home or classroom; the community; vocational settings; recreational settings; and special pedestrian situations (for…

  17. The Use of Traffic Sounds by Blind Pedestrians.

    ERIC Educational Resources Information Center

    Chew, Stephen L.

    A series of experiments were conducted to study variables affecting the alignment of blind pedestrians at street intersections. In the first two studies blindfolded sighted students, serving as adventitiously blind people undergoing mobility training, learned one of three strategies: no concrete strategy, tracking, and tracking and compensation.…

  18. Phonographic signal with a fractional-order chaotic system: a novel and simple algorithm for analyzing residual arteriovenous access stenosis.

    PubMed

    Chen, Wei-Ling; Chen, Tainsong; Lin, Chia-Hung; Chen, Pei-Jarn; Kan, Chung-Dann

    2013-09-01

    To detect the early developmental stages of arteriovenous access (AVA) stenosis in hemodialysis patients, this study explored a stenosis detector based on the Burg method and the fractional-order chaos system (FOCS). The bruit developed by the blood flowing through AVA can be a viable noninvasive strategy for monitoring AVA functions. We used the Burg method of the autoregressive model to estimate the frequency spectra of phonographic signals recorded by an electronic stethoscope in patients' AVAs and to identify the spectral peaks in the region of 25-800 Hz. The frequency spectra differed significantly between normal and stenosis statuses in AVA. We found that the frequency and amplitude in power spectra analysis varied in accordance with the severity of AVA stenosis. However, the correlation of these parameters for classifying the degree of stenosis is limited when only using the Burg method. Therefore, we used an FOCS to monitor the differing frequency spectra between the normal condition and AVA stenosis. The variances of these two conditions were dynamic errors that were the coupling variables that tracked the responses between the master system and the slave system. A total of 42 patients who had received percutaneous transluminal angioplasty (PTA) for their failing AVAs was recruited for this study. In this study, the dynamic error, Index Ψ, was used to calculate the frequency spectrum redistribution in patients undergoing PTA. In addition, ΔImp was the index used to evaluate improvements in the luminal diameter between pre- and post-PTA. Therefore, we used linear regression to model the relationship between ΔImp and Index Ψ. The findings indicate that the proposed method has enhanced efficiency, especially in the venous anastomosis (V-site). The FOCS is a novel and simple algorithm for analyzing the residual AVA stenosis of PTA treatment. PMID:23645205

  19. Traffic Instabilities in Self-Organized Pedestrian Crowds

    PubMed Central

    Moussaïd, Mehdi; Guillot, Elsa G.; Moreau, Mathieu; Fehrenbach, Jérôme; Chabiron, Olivier; Lemercier, Samuel; Pettré, Julien; Appert-Rolland, Cécile; Degond, Pierre; Theraulaz, Guy

    2012-01-01

    In human crowds as well as in many animal societies, local interactions among individuals often give rise to self-organized collective organizations that offer functional benefits to the group. For instance, flows of pedestrians moving in opposite directions spontaneously segregate into lanes of uniform walking directions. This phenomenon is often referred to as a smart collective pattern, as it increases the traffic efficiency with no need of external control. However, the functional benefits of this emergent organization have never been experimentally measured, and the underlying behavioral mechanisms are poorly understood. In this work, we have studied this phenomenon under controlled laboratory conditions. We found that the traffic segregation exhibits structural instabilities characterized by the alternation of organized and disorganized states, where the lifetime of well-organized clusters of pedestrians follow a stretched exponential relaxation process. Further analysis show that the inter-pedestrian variability of comfortable walking speeds is a key variable at the origin of the observed traffic perturbations. We show that the collective benefit of the emerging pattern is maximized when all pedestrians walk at the average speed of the group. In practice, however, local interactions between slow- and fast-walking pedestrians trigger global breakdowns of organization, which reduce the collective and the individual payoff provided by the traffic segregation. This work is a step ahead toward the understanding of traffic self-organization in crowds, which turns out to be modulated by complex behavioral mechanisms that do not always maximize the group's benefits. The quantitative understanding of crowd behaviors opens the way for designing bottom-up management strategies bound to promote the emergence of efficient collective behaviors in crowds. PMID:22457615

  20. Investigation of a role for ghrelin signaling in binge-like feeding in mice under limited access to high-fat diet.

    PubMed

    King, S J; Rodrigues, T; Watts, A; Murray, E; Wilson, A; Abizaid, A

    2016-04-01

    Binge eating is defined by the consumption of an excessive amount of food in a short time, reflecting a form of hedonic eating that is not necessarily motivated by caloric need. Foods consumed during a binge are also often high in fat and/or sugar. Ghrelin, signaling centrally via the growth-hormone secretagogue receptor (GHSR), stimulates growth hormone release and appetite. GHSR signaling also enhances the rewarding value of palatable foods and increases the motivation for such foods. As ghrelin interacts directly with dopaminergic reward circuitry, shown to be involved in binge eating, the current studies explored the role of GHSR signaling in a limited access model of binge eating in mice. In this model, mice received either intermittent (INT) or daily (DAILY) access to a nutritionally complete high-fat diet (HFD) for 2h late in the light cycle, alongside 24-h ad libitum chow. In CD-1 mice, 2-h exposure to HFD generated substantial binge-like intake of HFD, as well as a binge-compensate pattern of 24-h daily intake. INT and daily groups did not differ in 2-h HFD consumption, while INT mice maintained stable intake of chow despite access to HFD. GHSR knock-out (KO) and wild-type (WT) mice both binged during HFD access, and exhibited the same binge-compensate pattern. INT GHSR KO mice did not binge as much as WT, while DAILY KO and WT were comparable. Overall, GHSR KO mice consumed fewer calories from HFD, regardless of access condition. GHSR KO mice also had reduced activation of the nucleus accumbens shell, but not core, following HFD consumption. These data support the ability of INT HFD in mice to induce a binge-compensate pattern of intake that emulates select components of binge eating in humans. There also appears to be a role for GHSR signaling in driving HFD consumption under these conditions, potentially via mediation of reward-related circuitry. PMID:26791525

  1. Analysis of 121 fatal passenger car-adult pedestrian accidents in China.

    PubMed

    Zhao, Hui; Yin, Zhiyong; Yang, Guangyu; Che, Xingping; Xie, Jingru; Huang, Wei; Wang, Zhengguo

    2014-10-01

    To study the characteristics of fatal vehicle-pedestrian accidents in China,a team was established and passenger car-pedestrian crash cases occurring between 2006 and 2011 in Beijing and Chongqing, China were collected. A total of 121 fatal passenger car-adult pedestrian collisions were sampled and analyzed. The pedestrian injuries were scored according to Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS). The demographical distributions of fatal pedestrian accidents differed from other pedestrian accidents. Among the victims, no significant discrepancy in the distribution of ISS and AIS in head, thorax, abdomen, and extremities by pedestrian age was found, while pedestrian behaviors prior to the crashes may affect the ISS. The distributions of AIS in head, thorax, and abdomen among the fatalities did not show any association with impact speeds or vehicle types, whereas there was a strong relationship between the ISS and impact speeds. Whether pedestrians died in the accident field or not was not associated with the ISS or AIS. The present results may be useful for not only forensic experts but also vehicle safety researchers. More investigations regarding fatal pedestrian accidents need be conducted in great detail. PMID:25287805

  2. Studies of vehicle lane-changing to avoid pedestrians with cellular automata

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Sun, Jian-Qiao

    2015-11-01

    This paper presents studies of interactions between vehicles and crossing pedestrians. A cellular automata system model of the traffic is developed, which includes a number of subsystem models such as the single-lane vehicle model, pedestrian model, interaction model and lane-changing model. The random street crossings of pedestrians are modeled as a Poisson process. The drivers of the passing vehicles are assumed to follow a safety-rule in order not to hit the pedestrians. The results of both single and multiple car simulations are presented. We have found that in general, the traffic can benefit from vehicle lane-changing to avoid road-crossing pedestrians. The traffic flow and average vehicle speed can be increased, which leads to higher traffic efficiency. The interactions between vehicles and pedestrians are reduced, which results in shorter vehicle decelerating time due to pedestrians and less switches of the driving mode, thus leads to the better energy economy. The traffic safety can be improved in the perspective of both vehicles and pedestrians. Finally, pedestrians can cross road faster. The negative effect of lane-changing is that pedestrians have to stay longer between the lanes in the crossing.

  3. Analyzing fault and severity in pedestrian-motor vehicle accidents in China.

    PubMed

    Zhang, Guangnan; Yau, Kelvin K W; Zhang, Xun

    2014-12-01

    The number of pedestrian-motor vehicle accidents and pedestrian deaths in China surged in recent years. However, a large scale empirical research on pedestrian traffic crashes in China is lacking. In this study, we identify significant risk factors associated with fault and severity in pedestrian-motor vehicle accidents. Risk factors in several different dimensions, including pedestrian, driver, vehicle, road and environmental factors, are considered. We analyze 6967 pedestrian traffic accident reports for the period 2006-2010 in Guangdong Province, China. These data, obtained from the Guangdong Provincial Security Department, are extracted from the Traffic Management Sector-Specific Incident Case Data Report. Pedestrian traffic crashes have a unique inevitability and particular high risk, due to pedestrians' fragility, slow movement and lack of lighting equipment. The empirical analysis of the present study has the following policy implications. First, traffic crashes in which pedestrians are at fault are more likely to cause serious injuries or death, suggesting that relevant agencies should pay attention to measures that prevent pedestrians from violating traffic rules. Second, both the attention to elderly pedestrians, male and experienced drivers, the penalty to drunk driving, speeding, driving without a driver's license and other violation behaviors should be strengthened. Third, vehicle safety inspections and safety training sessions for truck drivers should be reinforced. Fourth, improving the road conditions and road lighting at night are important measures in reducing the probability of accident casualties. Fifth, specific road safety campaigns in rural areas, and education programs especially for young children and teens should be developed and promoted. Moreover, we reveal a country-specific factor, hukou, which has significant effect on the severity in pedestrian accidents due to the discrepancy in the level of social insurance/security, suggesting

  4. A Poisson-lognormal conditional-autoregressive model for multivariate spatial analysis of pedestrian crash counts across neighborhoods.

    PubMed

    Wang, Yiyi; Kockelman, Kara M

    2013-11-01

    This work examines the relationship between 3-year pedestrian crash counts across Census tracts in Austin, Texas, and various land use, network, and demographic attributes, such as land use balance, residents' access to commercial land uses, sidewalk density, lane-mile densities (by roadway class), and population and employment densities (by type). The model specification allows for region-specific heterogeneity, correlation across response types, and spatial autocorrelation via a Poisson-based multivariate conditional auto-regressive (CAR) framework and is estimated using Bayesian Markov chain Monte Carlo methods. Least-squares regression estimates of walk-miles traveled per zone serve as the exposure measure. Here, the Poisson-lognormal multivariate CAR model outperforms an aspatial Poisson-lognormal multivariate model and a spatial model (without cross-severity correlation), both in terms of fit and inference. Positive spatial autocorrelation emerges across neighborhoods, as expected (due to latent heterogeneity or missing variables that trend in space, resulting in spatial clustering of crash counts). In comparison, the positive aspatial, bivariate cross correlation of severe (fatal or incapacitating) and non-severe crash rates reflects latent covariates that have impacts across severity levels but are more local in nature (such as lighting conditions and local sight obstructions), along with spatially lagged cross correlation. Results also suggest greater mixing of residences and commercial land uses is associated with higher pedestrian crash risk across different severity levels, ceteris paribus, presumably since such access produces more potential conflicts between pedestrian and vehicle movements. Interestingly, network densities show variable effects, and sidewalk provision is associated with lower severe-crash rates. PMID:24036167

  5. Measures of activity-based pedestrian exposure to the risk of vehicle-pedestrian collisions: space-time path vs. potential path tree methods.

    PubMed

    Yao, Shenjun; Loo, Becky P Y; Lam, Winnie W Y

    2015-02-01

    Research on the extent to which pedestrians are exposed to road collision risk is important to the improvement of pedestrian safety. As precise geographical information is often difficult and costly to collect, this study proposes a potential path tree method derived from time geography concepts in measuring pedestrian exposure. With negative binomial regression (NBR) and geographically weighted Poisson regression (GWPR) models, the proposed probabilistic two-anchor-point potential path tree (PPT) approach (including the equal and weighted PPT methods) are compared with the deterministic space-time path (STP) method. The results indicate that both STP and PPT methods are useful tools in measuring pedestrian exposure. While the STP method can save much time, the PPT methods outperform the STP method in explaining the underlying vehicle-pedestrian collision pattern. Further research efforts are needed to investigate the influence of walking speed and route choice. PMID:25555021

  6. Pedestrian and traffic safety in parking lots at SNL/NM : audit background report.

    SciTech Connect

    Sanchez, Paul Ernest

    2009-03-01

    This report supplements audit 2008-E-0009, conducted by the ES&H, Quality, Safeguards & Security Audits Department, 12870, during fall and winter of FY 2008. The study evaluates slips, trips and falls, the leading cause of reportable injuries at Sandia. In 2007, almost half of over 100 of such incidents occurred in parking lots. During the course of the audit, over 5000 observations were collected in 10 parking lots across SNL/NM. Based on benchmarks and trends of pedestrian behavior, the report proposes pedestrian-friendly features and attributes to improve pedestrian safety in parking lots. Less safe pedestrian behavior is associated with older parking lots lacking pedestrian-friendly features and attributes, like those for buildings 823, 887 and 811. Conversely, safer pedestrian behavior is associated with newer parking lots that have designated walkways, intra-lot walkways and sidewalks. Observations also revealed that motorists are in widespread noncompliance with parking lot speed limits and stop signs and markers.

  7. Experiment and simulation of the bidirectional pedestrian flow model with overtaking and herding behavior

    NASA Astrophysics Data System (ADS)

    Hu, Jun; Li, Zhongwen; Zhang, Hong; Wei, Juan; You, Lei; Chen, Peng

    2015-04-01

    In order to effectively depict the characteristics of bidirectional pedestrian flow, a novel pedestrian flow model is proposed based on cellular automata. At first, according to direction gain, velocity gain and herding gain, the calculation formula of target position is defined, and the walking rules by combining overtaking behavior and herding behavior are given in the model. Meanwhile, the actual channel is used for experiments, where the self-organizing effect formed by pedestrian flow is observed. The simulation platform is established to study the key factors influencing pedestrian flow characteristics. The numerical analysis results showed that when the pedestrian density in the channel reached to the critical degree, the overtaking behavior can easily produce jamming. Moreover, pedestrians' rational choice is good for relieving jamming.

  8. Walking the line: Understanding pedestrian behaviour and risk at rail level crossings with cognitive work analysis.

    PubMed

    Read, Gemma J M; Salmon, Paul M; Lenné, Michael G; Stanton, Neville A

    2016-03-01

    Pedestrian fatalities at rail level crossings (RLXs) are a public safety concern for governments worldwide. There is little literature examining pedestrian behaviour at RLXs and no previous studies have adopted a formative approach to understanding behaviour in this context. In this article, cognitive work analysis is applied to understand the constraints that shape pedestrian behaviour at RLXs in Melbourne, Australia. The five phases of cognitive work analysis were developed using data gathered via document analysis, behavioural observation, walk-throughs and critical decision method interviews. The analysis demonstrates the complex nature of pedestrian decision making at RLXs and the findings are synthesised to provide a model illustrating the influences on pedestrian decision making in this context (i.e. time, effort and social pressures). Further, the CWA outputs are used to inform an analysis of the risks to safety associated with pedestrian behaviour at RLXs and the identification of potential interventions to reduce risk. PMID:26518501

  9. Assessment of models for pedestrian dynamics with functional principal component analysis

    NASA Astrophysics Data System (ADS)

    Chraibi, Mohcine; Ensslen, Tim; Gottschalk, Hanno; Saadi, Mohamed; Seyfried, Armin

    2016-06-01

    Many agent based simulation approaches have been proposed for pedestrian flow. As such models are applied e.g. in evacuation studies, the quality and reliability of such models is of vital interest. Pedestrian trajectories are functional data and thus functional principal component analysis is a natural tool to assess the quality of pedestrian flow models beyond average properties. In this article we conduct functional Principal Component Analysis (PCA) for the trajectories of pedestrians passing through a bottleneck. In this way it is possible to assess the quality of the models not only on basis of average values but also by considering its fluctuations. We benchmark two agent based models of pedestrian flow against the experimental data using PCA average and stochastic features. Functional PCA proves to be an efficient tool to detect deviation between simulation and experiment and to assess quality of pedestrian models.

  10. The influence of traffic signal solutions on self-reported road-crossing behavior.

    PubMed

    Di Stasi, Leandro L; Megías, Alberto; Cándido, Antonio; Maldonado, Antonio; Catena, Andrés

    2014-01-01

    Injury to pedestrians is a major safety hazard in many countries. Since the beginning of the last century, modern cities have been designed around the use of motor vehicles despite the unfavourable interactions between the vehicles and pedestrians. This push towards urbanization resulted in a substantial number of crashes and fatalities involving pedestrians every day, all over the world. Thus, improving the design of urban cities and townships is a pressing issue for modern society. The study presented here provides a characterization of pedestrian safety problems, with the emphasis on signalized crosswalks (i.e. traffic signal) design solutions. We tested the impact of seven different traffic light configurations (steady [green, yellow, and red], flashing [green, yellow, and red], and light off) on pedestrian self-reported road-crossing behavior, using a 11-point scale -ranging from 0 ("I never cross in this situation") to 10 ("I always cross in this situation"). Results showed that mandatory solutions (steady green vs. steady red) are the best solutions to avoid unsafe pedestrian behaviors while crossing controlled intersections (frequency of crossing: Mgreen = 9.4 ± 1 vs. Mred = 2.6 ± 2). These findings offer important guidelines for the design of future traffic signals for encouraging a pedestrian/transit-friendly environment. PMID:26055356

  11. Dynamic analysis of pedestrian crossing behaviors on traffic flow at unsignalized mid-block crosswalks

    NASA Astrophysics Data System (ADS)

    Liu, Gang; He, Jing; Luo, Zhiyong; Yang, Wunian; Zhang, Xiping

    2015-05-01

    It is important to study the effects of pedestrian crossing behaviors on traffic flow for solving the urban traffic jam problem. Based on the Nagel-Schreckenberg (NaSch) traffic cellular automata (TCA) model, a new one-dimensional TCA model is proposed considering the uncertainty conflict behaviors between pedestrians and vehicles at unsignalized mid-block crosswalks and defining the parallel updating rules of motion states of pedestrians and vehicles. The traffic flow is simulated for different vehicle densities and behavior trigger probabilities. The fundamental diagrams show that no matter what the values of vehicle braking probability, pedestrian acceleration crossing probability, pedestrian backing probability and pedestrian generation probability, the system flow shows the "increasing-saturating-decreasing" trend with the increase of vehicle density; when the vehicle braking probability is lower, it is easy to cause an emergency brake of vehicle and result in great fluctuation of saturated flow; the saturated flow decreases slightly with the increase of the pedestrian acceleration crossing probability; when the pedestrian backing probability lies between 0.4 and 0.6, the saturated flow is unstable, which shows the hesitant behavior of pedestrians when making the decision of backing; the maximum flow is sensitive to the pedestrian generation probability and rapidly decreases with increasing the pedestrian generation probability, the maximum flow is approximately equal to zero when the probability is more than 0.5. The simulations prove that the influence of frequent crossing behavior upon vehicle flow is immense; the vehicle flow decreases and gets into serious congestion state rapidly with the increase of the pedestrian generation probability.

  12. Impact of social and technological distraction on pedestrian crossing behaviour: an observational study

    PubMed Central

    Thompson, Leah L; Rivara, Frederick P; Ayyagari, Rajiv C; Ebel, Beth E

    2013-01-01

    Objectives The objective of the present work was to study the impact of technological and social distraction on cautionary behaviours and crossing times in pedestrians. Methods Pedestrians were observed at 20 high-risk intersections during 1 of 3 randomly assigned time windows in 2012. Observers recorded demographic and behavioural information, including use of a mobile device (talking on the phone, text messaging, or listening to music). We examined the association between distraction and crossing behaviours, adjusting for age and gender. All multivariate analyses were conducted with random effect logistic regression (binary outcomes) and random effect linear regression (continuous outcomes), accounting for clustering by site. Results Observers recorded crossing behaviours for 1102 pedestrians. Nearly one-third (29.8%) of all pedestrians performed a distracting activity while crossing. Distractions included listening to music (11.2%), text messaging (7.3%) and using a handheld phone (6.2%). Text messaging, mobile phone use and talking with a companion increased crossing time. Texting pedestrians took 1.87 additional seconds (18.0%) to cross the average intersection (3.4 lanes), compared to undistracted pedestrians. Texting pedestrians were 3.9 times more likely than undistracted pedestrians to display at least 1 unsafe crossing behaviour (disobeying the lights, crossing mid-intersection, or failing to look both ways). Pedestrians listening to music walked more than half a second (0.54) faster across the average intersection than undistracted pedestrians. Conclusions Distracting activity is common among pedestrians, even while crossing intersections. Technological and social distractions increase crossing times, with text messaging associated with the highest risk. Our findings suggest the need for intervention studies to reduce risk of pedestrian injury. PMID:23243104

  13. The influence of conformity and group identity on drink walking intentions: comparing intentions to drink walk across risky pedestrian crossing scenarios.

    PubMed

    McGhie, Alexandra; Lewis, Ioni; Hyde, Melissa K

    2012-03-01

    Despite the dangers associated with drink walking, limited research is currently available regarding the factors which influence individuals to engage in this risky behaviour. This study examined the influence of psychosocial factors upon individuals' intentions to drink walk across four experimental scenarios (and a control condition). Specifically, a 2×2 repeated measures design was utilised in which all of the scenarios incorporated a risky pedestrian crossing situation (i.e., a pedestrian crossing against a red man signal) but differed according to the level of group identity (i.e., low/strangers and high/friends) and conformity (low and high). Individuals were assessed for their intentions to drink walk within each of these different scenarios. Undergraduate students (N=151), aged 17-30 years, completed a questionnaire. Overall, most of the study's hypotheses were supported with individuals reporting the highest intentions to drink walk when in the presence of friends (i.e., high group identity) and their friends were said to be also crossing against the red man signal (i.e., high conformity). The findings may have significant implications for the design of countermeasures to reduce drink walking. For instance, the current findings would suggest that potentially effective strategies may be to promote resilience to peer influence as well as highlight the negative consequences associated with following the behaviour of other intoxicated pedestrians who are crossing against a red signal. PMID:22269552

  14. On entropy weak solutions of Hughes' model for pedestrian motion

    NASA Astrophysics Data System (ADS)

    El-Khatib, Nader; Goatin, Paola; Rosini, Massimiliano D.

    2013-04-01

    We consider a generalized version of Hughes' macroscopic model for crowd motion in the one-dimensional case. It consists in a scalar conservation law accounting for the conservation of the number of pedestrians, coupled with an eikonal equation giving the direction of the flux depending on pedestrian density. As a result of this non-trivial coupling, we have to deal with a conservation law with space-time discontinuous flux, whose discontinuity depends non-locally on the density itself. We propose a definition of entropy weak solution, which allows us to recover a maximum principle. Moreover, we study the structure of the solutions to Riemann-type problems, and we construct them explicitly for small times, depending on the choice of the running cost in the eikonal equation. In particular, aiming at the optimization of the evacuation time, we propose a strategy that is optimal in the case of high densities. All results are illustrated by numerical simulations.

  15. Comparison of intersecting pedestrian flows based on experiments

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Seyfried, A.

    2014-07-01

    Intersections of pedestrian flows feature multiple types, varying in the numbers of flow directions as well as intersecting angles. In this article results from intersecting flow experiments with two different intersecting angles are compared. To analyze the transport capabilities the Voronoi method is used to resolve the fine structure of the resulting velocity-density relations and spatial dependence of the measurements. The fundamental diagrams of various flow types are compared and show no apparent difference with respect to the intersecting angle 90° and 180°. This result indicates that head-on conflicts of different types of flow have the same influence on the transport properties of the system, which demonstrates the high self-organization capabilities of pedestrians.

  16. Close to real-time robust pedestrian detection and tracking

    NASA Astrophysics Data System (ADS)

    Lipetski, Y.; Loibner, G.; Sidla, O.

    2015-03-01

    Fully automated video based pedestrian detection and tracking is a challenging task with many practical and important applications. We present our work aimed to allow robust and simultaneously close to real-time tracking of pedestrians. The presented approach is stable to occlusions, lighting conditions and is generalized to be applied on arbitrary video data. The core tracking approach is built upon tracking-by-detections principle. We describe our cascaded HOG detector with successive CNN verification in detail. For the tracking and re-identification task, we did an extensive analysis of appearance based features as well as their combinations. The tracker was tested on many hours of video data for different scenarios; the results are presented and discussed.

  17. Simulation of pedestrian evacuation based on an improved dynamic parameter model

    NASA Astrophysics Data System (ADS)

    Zhu, Nuo; Jia, Bin; Shao, Chun-Fu; Yue, Hao

    2012-05-01

    An improved dynamic parameter model is presented based on cellular automata. The dynamic parameters, including direction parameter, empty parameter, and cognition parameter, are formulated to simplify tactically the process of making decisions for pedestrians. The improved model reflects the judgement of pedestrians on surrounding conditions and the action of choosing or decision. According to the two-dimensional cellular automaton Moore neighborhood we establish the pedestrian moving rule, and carry out corresponding simulations of pedestrian evacuation. The improved model considers the impact of pedestrian density near exits on the evacuation process. Simulated and experimental results demonstrate that the improvement makes sense due to the fact that except for the spatial distance to exits, people also choose an exit according to the pedestrian density around exits. The impact factors α, β, and γ are introduced to describe transition payoff, and their optimal values are determined through simulation. Moreover, the effects of pedestrian distribution, pedestrian density, and the width of exits on the evacuation time are discussed. The optimal exit layout, i.e., the optimal position and width, is offered. The comparison between the simulated results obtained with the improved model and that from a previous model and experiments indicates that the improved model can reproduce experimental results well. Thus, it has great significance for further study, and important instructional meaning for pedestrian evacuation so as to reduce the number of casualties.

  18. Community-based pedestrian safety training in virtual reality: A pragmatic trial.

    PubMed

    Schwebel, David C; Combs, Tabitha; Rodriguez, Daniel; Severson, Joan; Sisiopiku, Virginia

    2016-01-01

    Child pedestrian injuries are a leading cause of mortality and morbidity across the United States and the world. Repeated practice at the cognitive-perceptual task of crossing a street may lead to safer pedestrian behavior. Virtual reality offers a unique opportunity for repeated practice without the risk of actual injury. This study conducted a pre-post within-subjects trial of training children in pedestrian safety using a semi-mobile, semi-immersive virtual pedestrian environment placed at schools and community centers. Pedestrian safety skills among a group of 44 seven- and eight-year-old children were assessed in a laboratory, and then children completed six 15-minute training sessions in the virtual pedestrian environment at their school or community center following pragmatic trial strategies over the course of three weeks. Following training, pedestrian safety skills were re-assessed. Results indicate improvement in delay entering traffic following training. Safe crossings did not demonstrate change. Attention to traffic and time to contact with oncoming vehicles both decreased somewhat, perhaps an indication that training was incomplete and children were in the process of actively learning to be safer pedestrians. The findings suggest virtual reality environments placed in community centers hold promise for teaching children to be safer pedestrians, but future research is needed to determine the optimal training dosage. PMID:26479677

  19. Motor vehicle collisions involving child pedestrians in eThekwini in 2007.

    PubMed

    Hobday, Michelle; Knight, Stephen

    2010-03-01

    The burden of disability and death on child pedestrians has not been widely researched in the developing world. Using the eThekwini Transport Authority database for 2007, data about collisions involving pedestrians under the age of 15 in the eThekwini metropolitan area were analysed. Incidence risk and proportions were calculated for risk factors involving pedestrians, drivers and the environment. Male pedestrians aged 5 to 9 were at highest risk of injury compared to other male pedestrians (IRR: 1.63; 95% CI: 1.38 to 1.91). This group also had the highest fatality risk (IRR: 2.12; 95% CI: 1.05 to 4.29). Male drivers had nearly five times the risk of involvement in pedestrian collisions compared to females. The highest proportion of fatal pedestrian collisions involved buses and trucks, on freeways, in wet conditions and at night. The findings point to the need to: (a) improve pedestrian visibility; (b) design safe routes to schools; and (c) develop practical roadside skills. For the first time in research in road traffic injuries, this study provides an overall picture of both fatal and non-fatal child pedestrian collisions in a South African municipality. PMID:20056732

  20. Effect of prediction on the self-organization of pedestrian counter flow

    NASA Astrophysics Data System (ADS)

    Wang, Ziyang; Ma, Jian; Zhao, Hui; Qin, Yong; Jia, Limin

    2012-08-01

    Pedestrians may predict the behavior of others and then adjust their movement accordingly to avoid potential conflicts in advance. Motivated by this fact, we propose a predictive control theory-based pedestrian counter flow model, which describes the predictive mechanism underlying pedestrian self-organization phenomena. In this model, a pedestrian will make in-advance-avoid behavior based on the estimation of future moving gain within a given predictive length to reduce potential conflicts. The future gain in the present model is affected by three factors, i.e. the predictive length, the smooth degree of entrance and the influential area of coming pedestrians. Simulation results of the model show that increasing predictive length has a remarkable effect on reducing conflicts, improving pedestrian velocity, smoothing pedestrian movement and stabilizing the self-organized lanes. When enlarging the influential area of coming pedestrians, pedestrians tend to aggregate to the formed self-organized lanes, which makes the lanes wider and the lane number reduced. Interestingly, moderate enlargement (of the influential area) will reduce conflicts significantly, while excessive enlargement will lead to an increase in conflicts. We also discuss the predictive effect toward the smooth degree of entrance. When there are some formed self-organized lanes in the system, the effect is significant, and it will make the lanes more regular and stable, while when the existing lanes are unstable, the effect has little impact on the system.

  1. Comparison study of the reactive and predictive dynamic models for pedestrian flow

    NASA Astrophysics Data System (ADS)

    Jiang, Yan-Qun; Zhang, Wei; Zhou, Shu-Guang

    2016-01-01

    This paper formulates the reactive and predictive dynamic models for pedestrian flow and presents a comparison of the two models. The path-choice behavior of pedestrians in the reactive dynamic model is described that pedestrians tend to walk along a path with the lowest instantaneous cost. The desired walking direction of pedestrians in the predictive dynamic model is chosen to minimize the actual cost based on predictive traffic conditions. An algorithm used to solve the two models encompasses a cell-centered finite volume method for a hyperbolic system of conservation laws and a time-dependent Hamilton-Jacobi equation, a fast sweeping method for an Eikonal-type equation, and a self-adaptive method of successive averages for an arisen discrete fixed point problem. The two models and their algorithm are applied to investigate the spatio-temporal patterns of flux or density and path-choice behaviors of pedestrian flow marching in a facility scattered with an obstacle. Numerical results show that the two models are able to capture macroscopic features of pedestrian flow, traffic instability and other complex nonlinear phenomena in pedestrian traffic, such as the formation of stop-and-go waves and clogging at bottlenecks. Different path-choice strategies of pedestrians cause different spatial distributions of pedestrian density specially in the high-density regions (near the obstacle and exits).

  2. Pedestrian injury risk and the effect of age.

    PubMed

    Niebuhr, Tobias; Junge, Mirko; Rosén, Erik

    2016-01-01

    Older adults and pedestrians both represent especially vulnerable groups in traffic. In the literature, hazards are usually described by the corresponding injury risks of a collision. This paper investigates the MAIS3+F risk (the risk of sustaining at least one injury of AIS 3 severity or higher, or fatal injury) for pedestrians in full-frontal pedestrian-to-passenger car collisions. Using some assumptions, a model-based approach to injury risk, allowing for the specification of individual injury risk parameters for individuals, is presented. To balance model accuracy and sample size, the GIDAS (German In-depth Accident Study) data set is divided into three age groups; children (0-14); adults (15-60); and older adults (older than 60). For each group, individual risk curves are computed. Afterwards, the curves are re-aggregated to the overall risk function. The derived model addresses the influence of age on the outcome of pedestrian-to-car accidents. The results show that older people compared with younger people have a higher MAIS3+F injury risk at all collision speeds. The injury risk for children behaves surprisingly. Compared to other age groups, their MAIS3+F injury risk is lower at lower collision speeds, but substantially higher once a threshold has been exceeded. The resulting injury risk curve obtained by re-aggregation looks surprisingly similar to the frequently used logistic regression function computed for the overall injury risk. However, for homogenous subgroups - such as the three age groups - logistic regression describes the typical risk behavior less accurately than the introduced model-based approach. Since the effect of demographic change on traffic safety is greater nowadays, there is a need to incorporate age into established models. Thus far, this is one of the first studies incorporating traffic participant age to an explicit risk function. The presented approach can be especially useful for the modeling and prediction of risks, and for the

  3. How simple rules determine pedestrian behavior and crowd disasters.

    PubMed

    Moussaïd, Mehdi; Helbing, Dirk; Theraulaz, Guy

    2011-04-26

    With the increasing size and frequency of mass events, the study of crowd disasters and the simulation of pedestrian flows have become important research areas. However, even successful modeling approaches such as those inspired by Newtonian force models are still not fully consistent with empirical observations and are sometimes hard to calibrate. Here, a cognitive science approach is proposed, which is based on behavioral heuristics. We suggest that, guided by visual information, namely the distance of obstructions in candidate lines of sight, pedestrians apply two simple cognitive procedures to adapt their walking speeds and directions. Although simpler than previous approaches, this model predicts individual trajectories and collective patterns of motion in good quantitative agreement with a large variety of empirical and experimental data. This model predicts the emergence of self-organization phenomena, such as the spontaneous formation of unidirectional lanes or stop-and-go waves. Moreover, the combination of pedestrian heuristics with body collisions generates crowd turbulence at extreme densities--a phenomenon that has been observed during recent crowd disasters. By proposing an integrated treatment of simultaneous interactions between multiple individuals, our approach overcomes limitations of current physics-inspired pair interaction models. Understanding crowd dynamics through cognitive heuristics is therefore not only crucial for a better preparation of safe mass events. It also clears the way for a more realistic modeling of collective social behaviors, in particular of human crowds and biological swarms. Furthermore, our behavioral heuristics may serve to improve the navigation of autonomous robots. PMID:21502518

  4. The directional flow of visual information transfer between pedestrians

    PubMed Central

    Gallup, Andrew C.; Chong, Andrew; Couzin, Iain D.

    2012-01-01

    Close behavioural coupling of visual orientation may provide a range of adaptive benefits to social species. In order to investigate the natural properties of gaze-following between pedestrians, we displayed an attractive stimulus in a frequently trafficked corridor within which a hidden camera was placed to detect directed gaze from passers-by. The presence of visual cues towards the stimulus by nearby pedestrians increased the probability of passers-by looking as well. In contrast to cueing paradigms used for laboratory research, however, we found that individuals were more responsive to changes in the visual orientation of those walking in the same direction in front of them (i.e. viewing head direction from behind). In fact, visual attention towards the stimulus diminished when oncoming pedestrians had previously looked. Information was therefore transferred more effectively behind, rather than in front of, gaze cues. Further analyses show that neither crowding nor group interactions were driving these effects, suggesting that, within natural settings gaze-following is strongly mediated by social interaction and facilitates acquisition of environmentally relevant information. PMID:22456331

  5. Modeling and simulating for congestion pedestrian evacuation with panic

    NASA Astrophysics Data System (ADS)

    Wang, Jinhuan; Zhang, Lei; Shi, Qiongyu; Yang, Peng; Hu, Xiaoming

    2015-06-01

    A new multi-agent based congestion evacuation model incorporating panic behavior is proposed in this paper for simulating pedestrian evacuation in public places such as a stadium. Different from the existing results, pedestrians in this model are divided into four classes and each pedestrian's status can be either normal, being overtaken, or casualty. The direction of action for each individual is affected by competitive ability, distance to the exits as well as number and density of occupants within the view field of the agent. Our simulations exhibit that during the evacuation process: (1) The agents gather in front of the exits spontaneously and present arched shapes close to the exits. (2) Under the panic state the agents cohere closely and almost do not change the target exit. So other alternative exits are ignored. (3) For the case without obstacle, the casualties under panic increase greatly. But if there are obstacles (chairs), the congestion can be alleviated. Thus the casualties are reduced. (4) If certain exit is partly clogged, the evacuation becomes more efficient when adding a virtual leader. The overall simulation results show that the proposed model can reproduce the real evacuation process in a stadium quite well.

  6. Forecasting pedestrian evacuation times by using swarm intelligence

    NASA Astrophysics Data System (ADS)

    Izquierdo, J.; Montalvo, I.; Pérez, R.; Fuertes, V. S.

    2009-04-01

    Many models have been developed to provide designers with methods for forecasting the time required for evacuation from various places under a variety of conditions. Particularly for high traffic buildings or buildings of cultural, governmental, or industrial importance, it is of paramount importance to properly evaluate and plan for the necessary evacuation time. To address this need, a number of models for pedestrian simulation, either considering the system as a whole or studying the behavior and decisions of individual pedestrians and their interactions with other pedestrians, have been developed over the years. In this work, a model for evacuation simulation and for estimating evacuation times is proposed. It is inspired by the so-called Particle Swarm Optimization (PSO). The multi-agent-based simulation characteristics of PSO and the way this technique combines individual and collective intelligence make it suitable for this problem. The PSO-based model presented here allows for assessment of the behavioral patterns followed by individuals during a rapid evacuation event. Evaluation of these behaviors can address a variety of public safety concerns, such as architectural design, evacuation protocol definition, and regulation of public space.

  7. Quantification of the level of crowdedness for pedestrian movements

    NASA Astrophysics Data System (ADS)

    Duives, Dorine C.; Daamen, Winnie; Hoogendoorn, Serge P.

    2015-06-01

    Within the realm of pedestrian research numerous measures have been proposed to estimate the level of crowdedness experienced by pedestrians. However, within the field of pedestrian traffic flow modelling there does not seem to be consensus on the question which of these measures performs best. This paper shows that the shape and scatter within the resulting fundamental diagrams differs a lot depending on the measure of crowdedness used. The main aim of the paper is to establish the advantages and disadvantages of the currently existing measures to quantify crowdedness in order to evaluate which measures provide both accurate and consistent results. The assessment is not only based on the theoretical differences, but also on the qualitative and quantitative differences between the resulting fundamental diagrams computed using the crowdedness measures on one and the same data set. The qualitative and quantitative functioning of the classical Grid-based measure is compared to with the X-T measure, an Exponentially Weighted Distance measure, and a Voronoi-Diagram measure. The consistency of relating these measures for crowdedness to the two macroscopic flow variables velocity and flow, the computational efficiency and the amount of scatter present within the fundamental diagrams produced by the implementation of the different measures are reviewed. It is found that the Voronoi-Diagram and X-T measure are the most efficient and consistent measures for crowdedness.

  8. Research resource: Gonadotropin-releasing hormone receptor-mediated signaling network in LbetaT2 cells: a pathway-based web-accessible knowledgebase.

    PubMed

    Fink, Marc Y; Pincas, Hanna; Choi, Soon Gang; Nudelman, German; Sealfon, Stuart C

    2010-09-01

    The GnRH receptor (GnRHR), expressed at the cell surface of the anterior pituitary gonadotrope, is critical for normal secretion of gonadotropins LH and FSH, pubertal development, and reproduction. The signaling network downstream of the GnRHR and the molecular bases of the regulation of gonadotropin expression have been the subject of intense research. The murine LbetaT2 cell line represents a mature gonadotrope and therefore is an important model for the study of GnRHR-signaling pathways and modulation of the gonadotrope cell by physiological regulators. In order to facilitate access to the information contained in this complex and evolving literature, we have developed a pathway-based knowledgebase that is web hosted. At present, using 106 relevant primary publications, we curated a comprehensive knowledgebase of the GnRHR signaling in the LbetaT2 cell in the form of a process diagram. Positive and negative controls of gonadotropin gene expression, which included GnRH itself, hypothalamic factors, gonadal steroids and peptides, as well as other hormones, were illustrated. The knowledgebase contains 187 entities and 206 reactions. It was assembled using CellDesigner software, which provides an annotated graphic representation of interactions, stored in Systems Biology Mark-up Language. We then utilized Biological Pathway Publisher, a software suite previously developed in our laboratory, to host the knowledgebase in a web-accessible format as a public resource. In addition, the network entities were linked to a public wiki, providing a forum for discussion, updating, and error correction. The GnRHR-signaling network is openly accessible at http://tsb.mssm.edu/pathwayPublisher/GnRHR_Pathway/GnRHR_Pathway_ index.html. PMID:20592162

  9. Interactions of Pedestrians Interlaced in T-Shaped Structure Using a Modified Multi-Field Cellular Automaton

    NASA Astrophysics Data System (ADS)

    Fu, Zhijian; Yang, Lizhong; Rao, Ping; Zhang, Taolin

    2013-04-01

    Little work has been done before in the study of separating pedestrian flow interlaced. Under open boundaries, the interaction of separating pedestrian flow interlaced in a T-shaped structure was simulated, using a modified multi-field cellular automaton updating synchronously. The free-jammed phase transition diagram of pedestrian flow and principles of the pedestrian interference were obtained. The movement of pedestrians is free flow in the low entrance density. While it is a complete jammed flow with the entrance density increasing to a certain level and little difference existing between the left moving probability and the right moving probability. Thus, the dominant factor influencing pedestrian flow is the interference of opposite pedestrian flows due to changing movement directions. And it is changing to an incomplete jammed flow with this difference increasing. Thus, the dominant factor is changing to the interference of the coincident pedestrian flow and the limitation of the bottleneck.

  10. Investigation of in-band transmission of both spectral amplitude coding/optical code division multiple-access and wavelength division multiplexing signals

    NASA Astrophysics Data System (ADS)

    Ashour, Isaac A. M.; Shaari, Sahbudin; Shalaby, Hossam M. H.; Menon, P. Susthitha

    2011-06-01

    The transmission of both optical code division multiple-access (OCDMA) and wavelength division multiplexing (WDM) users on the same band is investigated. Code pulses of spectral amplitude coding (SAC)/optical code division multiple-access (CDMA) are overlaid onto a multichannel WDM system. Notch filters are utilized in order to suppress the WDM interference signals for detection of optical broadband CDMA signals. Modified quadratic congruence (MQC) codes are used as the signature codes for the SAC/OCDMA system. The proposed system is simulated and its performance in terms of both the bit-error rate and Q-factor are determined. In addition, eavesdropper probability of error-free code detection is evaluated. Our results are compared to traditional nonhybrid systems. It is concluded that the proposed hybrid scheme still achieves acceptable performance. In addition, it provides enhanced data confidentiality as compared to the scheme with SAC/OCDMA only. It is also shown that the performance of the proposed system is limited by the interference of the WDM signals. Furthermore, the simulation illustrates the tradeoff between the performance and confidentiality for authorized users.

  11. 10 CFR 431.224 - Uniform test method for the measurement of energy consumption for traffic signal modules and...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... traffic signal modules and pedestrian modules. For purposes of 10 CFR part 431 and EPCA, the test... conducting the test procedure set forth in Environmental Protection Agency, “ENERGY STAR Program...

  12. 10 CFR 431.224 - Uniform test method for the measurement of energy consumption for traffic signal modules and...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... traffic signal modules and pedestrian modules. For purposes of 10 CFR part 431 and EPCA, the test... conducting the test procedure set forth in Environmental Protection Agency, “ENERGY STAR Program...

  13. Magnetic, Acceleration Fields and Gyroscope Quaternion (MAGYQ)-based attitude estimation with smartphone sensors for indoor pedestrian navigation.

    PubMed

    Renaudin, Valérie; Combettes, Christophe

    2014-01-01

    The dependence of proposed pedestrian navigation solutions on a dedicated infrastructure is a limiting factor to the deployment of location based services. Consequently self-contained Pedestrian Dead-Reckoning (PDR) approaches are gaining interest for autonomous navigation. Even if the quality of low cost inertial sensors and magnetometers has strongly improved, processing noisy sensor signals combined with high hand dynamics remains a challenge. Estimating accurate attitude angles for achieving long term positioning accuracy is targeted in this work. A new Magnetic, Acceleration fields and GYroscope Quaternion (MAGYQ)-based attitude angles estimation filter is proposed and demonstrated with handheld sensors. It benefits from a gyroscope signal modelling in the quaternion set and two new opportunistic updates: magnetic angular rate update (MARU) and acceleration gradient update (AGU). MAGYQ filter performances are assessed indoors, outdoors, with dynamic and static motion conditions. The heading error, using only the inertial solution, is found to be less than 10° after 1.5 km walking. The performance is also evaluated in the positioning domain with trajectories computed following a PDR strategy. PMID:25474379

  14. Magnetic, Acceleration Fields and Gyroscope Quaternion (MAGYQ)-Based Attitude Estimation with Smartphone Sensors for Indoor Pedestrian Navigation

    PubMed Central

    Renaudin, Valérie; Combettes, Christophe

    2014-01-01

    The dependence of proposed pedestrian navigation solutions on a dedicated infrastructure is a limiting factor to the deployment of location based services. Consequently self-contained Pedestrian Dead-Reckoning (PDR) approaches are gaining interest for autonomous navigation. Even if the quality of low cost inertial sensors and magnetometers has strongly improved, processing noisy sensor signals combined with high hand dynamics remains a challenge. Estimating accurate attitude angles for achieving long term positioning accuracy is targeted in this work. A new Magnetic, Acceleration fields and GYroscope Quaternion (MAGYQ)-based attitude angles estimation filter is proposed and demonstrated with handheld sensors. It benefits from a gyroscope signal modelling in the quaternion set and two new opportunistic updates: magnetic angular rate update (MARU) and acceleration gradient update (AGU). MAGYQ filter performances are assessed indoors, outdoors, with dynamic and static motion conditions. The heading error, using only the inertial solution, is found to be less than 10° after 1.5 km walking. The performance is also evaluated in the positioning domain with trajectories computed following a PDR strategy. PMID:25474379

  15. Cellular automata (CA) simulation of the interaction of vehicle flows and pedestrian crossings on urban low-grade uncontrolled roads

    NASA Astrophysics Data System (ADS)

    Chen, Qun; Wang, Yan

    2015-08-01

    This paper discusses the interaction of vehicle flows and pedestrian crossings on uncontrolled low-grade roads or branch roads without separating barriers in cities where pedestrians may cross randomly from any location on both sides of the road. The rules governing pedestrian street crossings are analyzed, and a cellular automata (CA) model to simulate the interaction of vehicle flows and pedestrian crossings is proposed. The influence of the interaction of vehicle flows and pedestrian crossings on the volume and travel time of the vehicle flow and the average wait time for pedestrians to cross is investigated through simulations. The main results of the simulation are as follows: (1) The vehicle flow volume decreases because of interruption from pedestrian crossings, but a small number of pedestrian crossings do not cause a significant delay to vehicles. (2) If there are many pedestrian crossings, slow vehicles will have little chance to accelerate, causing travel time to increase and the vehicle flow volume to decrease. (3) The average wait time for pedestrians to cross generally decreases with a decrease in vehicle flow volume and also decreases with an increase in the number of pedestrian crossings. (4) Temporal and spatial characteristics of vehicle flows and pedestrian flows and some interesting phenomena such as "crossing belt" and "vehicle belt" are found through the simulations.

  16. The walking environment in Lima, Peru and pedestrian-motor vehicle collisions: An exploratory analysis

    PubMed Central

    Quistberg, D. Alex; Koepsell, Thomas D.; Miranda, J. Jaime; Boyle, Linda Ng; Johnston, Brian D.; Ebel, Beth E.

    2014-01-01

    Objective Pedestrians comprise 78% of the road fatalities in Peru. The objective of this study was to explore the relationship between the walking environment and pedestrian-motor vehicle collisions. Methods A matched case-control study was used to detect the odds of a pedestrian-motor vehicle collision at a pedestrian crossing location. Data were collected within eleven sampled police commissaries in Lima, Peru. Results In a multivariable model adjusting for vehicle and pedestrian flow, pedestrian collisions were less likely in the presence of a curb and sidewalk on both roadway sides (Odds Ratio [OR] 0.19, 95% Confidence Interval [CI] 0.11–0.33) or a pedestrian barricade (OR 0.11, 95% CI 0.01–0.81). There was a greater risk of collisions for each street vendor present (OR 2.82, 95% CI 1.59–5.00) or if any parked vehicles (OR 3.67, 95% CI 1.18–11.4) were present. Conclusions Improving or addressing these potentially modifiable features of the walking environment could improve pedestrian safety in Lima and in similar urban settings in low and middle-income countries. PMID:24950345

  17. 49 CFR 222.27 - How does this rule affect pedestrian grade crossings?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MUTCD. (2) Each approach to every pedestrian grade crossing within a New Partial Quiet Zone shall be... applicable. Such sign shall conform to the standards contained in the MUTCD. (3) Each approach to every... standards contained in the MUTCD. (4) Each approach to every pedestrian grade crossing within a...

  18. 49 CFR 222.27 - How does this rule affect pedestrian grade crossings?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... MUTCD. (2) Each approach to every pedestrian grade crossing within a New Partial Quiet Zone shall be... applicable. Such sign shall conform to the standards contained in the MUTCD. (3) Each approach to every... standards contained in the MUTCD. (4) Each approach to every pedestrian grade crossing within a...

  19. 49 CFR 222.27 - How does this rule affect pedestrian grade crossings?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MUTCD. (2) Each approach to every pedestrian grade crossing within a New Partial Quiet Zone shall be... applicable. Such sign shall conform to the standards contained in the MUTCD. (3) Each approach to every... standards contained in the MUTCD. (4) Each approach to every pedestrian grade crossing within a...

  20. 49 CFR 222.27 - How does this rule affect pedestrian grade crossings?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MUTCD. (2) Each approach to every pedestrian grade crossing within a New Partial Quiet Zone shall be... applicable. Such sign shall conform to the standards contained in the MUTCD. (3) Each approach to every... standards contained in the MUTCD. (4) Each approach to every pedestrian grade crossing within a...

  1. 49 CFR 222.27 - How does this rule affect pedestrian grade crossings?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MUTCD. (2) Each approach to every pedestrian grade crossing within a New Partial Quiet Zone shall be... applicable. Such sign shall conform to the standards contained in the MUTCD. (3) Each approach to every... standards contained in the MUTCD. (4) Each approach to every pedestrian grade crossing within a...

  2. Impact of a pilot Walking School Bus intervention on children's pedestrian safety behaviors [abstract

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Walking School Bus (WSB) programs have increased children's active commuting to school and physical activity; however, the impact on child pedestrian safety behaviors has not been studied. Our study objective was to evaluate the impact of a WSB program on children's pedestrian safety behaviors. We c...

  3. Analysis of the pedestrian arching at bottleneck based on a bypassing behavior model

    NASA Astrophysics Data System (ADS)

    Tang, Ming; Jia, Hongfei; Ran, Bin; Li, Jun

    2016-07-01

    A bypassing behavior model was proposed, in which the local optimal decision behavior in the strategy level was modeled in velocity-time domain, to describe how pedestrians bypass the local obstacles considering the relative speed. The model contains (1) pedestrian visual and contact information acquisition; (2) motion state prediction of the local obstacles based on the visual and contact information; (3) pedestrian bypass strategy modeling in the velocity-time domain; (4) moving and overlapping solution. In the numerical solution, velocity domain was divided into n equal angle, the value of n ranges from 2 to infinity, the Manhattan space was refined gradually to Euclid Space accordingly, in which the movement of pedestrians was described. The model was applied to the analysis of pedestrian arching at the bottleneck in the emergent evacuation situation. (1) The results showed that the formation of the pedestrian arching at the bottleneck was deformation pressure, because many pedestrians try to pass through the bottleneck simultaneously, even in the absence of friction, the pedestrian arching still occurs; (2) In the emergent situation, we are more concerned about the bottleneck attribution of resistance to form the arching, the calculation and simulation results showed that the probability of an arching and the bottleneck width is an exponential function relationship, so when the stampede occurs in the middle of the bottleneck, the probability of arching will increase exponentially.

  4. A Methodology for the Geometric Standardization of Vehicle Hoods to Compare Real-World Pedestrian Crashes

    PubMed Central

    Koetje, Bethany D.; Grabowski, Jurek G.

    2008-01-01

    This paper describes a standardization method that allows injury researchers to directly compare pedestrian hood contact points across a variety of hood sizes and geometries. To standardize hood contact locations a new coordinate system was created at the geometric center of the hood. Standardizing hood contact locations was done by turning each coordinate location into a ratio of the entire length or width of the hood. The standardized pedestrian contact locations could then be compared for various hood sizes. The standardized hood was divided into a three-by-three grid to aggregate contact points into hood regions. Data was obtained from the National Highway Traffic Safety Administration’s Pedestrian Crash Data Study from 1994 to 1998. To understand injury severity with respect to pedestrian hood contact location, the injuries were narrowed to the single most severe Abreviated Injury Scale injury to the pedestrian and hood location at which that injury was sustained. Of the 97 pedestrian/vehicle cases, pedestrians received 270 injuries from 141 unique hood contact locations. After standardization, 36%, 28%, 36% of all contact points were located on the left, center and right side of the hood respectively. Vertically, 26%, 45%, 28% of contacts occurred at the front, middle, and rear regions of the hood respectively. The middle passenger side of the hood contained the most number of AIS 3+ injuries. By using real-world crash data, engineers can make evidence based decisions to decease the severity of pedestrian injuries. PMID:19026236

  5. Driver Behavior in Yielding to Sighted and Blind Pedestrians at Roundabouts

    ERIC Educational Resources Information Center

    Geruschat, Duane R.; Hassan, Shirin E.

    2005-01-01

    This study evaluated drivers' behavior in yielding the right-of-way to sighted and blind pedestrians who stood at different stopping distances from the crosswalk lines at entry and exit lanes at two different roundabouts. The findings demonstrate that drivers' willingness to yield to pedestrians is affected by whether they are attempting to cross…

  6. Experimental study of pedestrian inflow in a room with a separate entrance and exit

    NASA Astrophysics Data System (ADS)

    Liu, Xiaodong; Song, Weiguo; Fu, Libi; Fang, Zhiming

    2016-01-01

    Pedestrian inflow process frequently occurs in various pedestrian facilities in our daily life. Great importance should be attached to the study of this process. In this paper, we explore the pedestrian inflow process in a room with a separate entrance and exit. Two kinds of experiments are conducted: experiment 1 has no inactive persons and primarily focuses on analyzing the features of the normal pedestrian inflow process and analyzing the representative spatial parameters in the steady state, while experiment 2 involves the influence of the inactive persons. In order to quantitatively discuss the distribution of pedestrians in the steady state, we adopt several analytical methods, such as the Voronoi diagram method, proxemics, and point pattern analysis. Some features of the inflow process are captured. The distribution of pedestrians in the steady state is not uniform. The proxemics and attraction to the exit are both considered to affect pedestrians' distribution in the inflow process. The presence of inactive persons may have an impact on both the inflow and outflow processes. Practical suggestions are provided for the managers of pedestrian facilities.

  7. An accident waiting to happen: a spatial approach to proactive pedestrian planning.

    PubMed

    Schneider, Robert J; Ryznar, Rhonda M; Khattak, Asad J

    2004-03-01

    There are about 75,000 pedestrian crashes in the United States each year. Approximately 5000 of these crashes are fatal, accounting for 12% of all roadway deaths. On college campuses, pedestrian exposure and crash-risk can be quite high. Therefore, we analyzed pedestrian crashes on the campus of the University of North Carolina at Chapel Hill (UNC) as a test case for our spatially-oriented prototype tool that combines perceived-risk (survey) data with police-reported crash data to obtain a more complete picture of pedestrian crash-risk. We use spatial analysis techniques combined with regression models to understand factors associated with risk. The spatial analysis is based on comparing two distributions, i.e. the locations of perceived-risk with police-reported crash locations. The differences between the two distributions are statistically significant, implying that certain locations on campus are perceived as dangerous, though pedestrian crashes have not yet occurred there, and there are actual locations of police-reported crashes that are not perceived to be dangerous by pedestrians or drivers. Furthermore, we estimate negative binomial regression models to combine pedestrian and automobile exposure with roadway characteristics and spatial/land use information. The models show that high exposure, incomplete sidewalks and high crosswalk density are associated with greater observed and perceived pedestrian crash-risk. Additionally, we found that people perceive a lower risk near university libraries, stadiums, and academic buildings, despite the occurrence of crashes. PMID:14642874

  8. Distributed Pedestrian Detection Alerts Based on Data Fusion with Accurate Localization

    PubMed Central

    García, Fernando; Jiménez, Felipe; Anaya, José Javier; Armingol, José María; Naranjo, José Eugenio; de la Escalera, Arturo

    2013-01-01

    Among Advanced Driver Assistance Systems (ADAS) pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner) and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided. PMID:24008284

  9. Spatial-size scaling of pedestrian groups under growing density conditions

    NASA Astrophysics Data System (ADS)

    Zanlungo, Francesco; Brščić, Dražen; Kanda, Takayuki

    2015-06-01

    We study the dependence on crowd density of the spatial size, configuration, and velocity of pedestrian social groups. We find that, in the investigated density range, the extension of pedestrian groups in the direction orthogonal to that of motion decreases linearly with the pedestrian density around them, both for two- and three-person groups. Furthermore, we observe that at all densities, three-person groups walk slower than two-person groups, and the latter are slower than individual pedestrians, the differences in velocities being weakly affected by density. Finally, we observe that three-person groups walk in a V-shaped formation regardless of density, with a distance between the pedestrians in the front and back again almost independent of density, although the configuration appears to be less stable at higher densities. These findings may facilitate the development of more realistic crowd dynamics models and simulators.

  10. Distributed pedestrian detection alerts based on data fusion with accurate localization.

    PubMed

    García, Fernando; Jiménez, Felipe; Anaya, José Javier; Armingol, José María; Naranjo, José Eugenio; de la Escalera, Arturo

    2013-01-01

    Among Advanced Driver Assistance Systems (ADAS) pedestrian detection is a common issue due to the vulnerability of pedestrians in the event of accidents. In the present work, a novel approach for pedestrian detection based on data fusion is presented. Data fusion helps to overcome the limitations inherent to each detection system (computer vision and laser scanner) and provides accurate and trustable tracking of any pedestrian movement. The application is complemented by an efficient communication protocol, able to alert vehicles in the surroundings by a fast and reliable communication. The combination of a powerful location, based on a GPS with inertial measurement, and accurate obstacle localization based on data fusion has allowed locating the detected pedestrians with high accuracy. Tests proved the viability of the detection system and the efficiency of the communication, even at long distances. By the use of the alert communication, dangerous situations such as occlusions or misdetections can be avoided. PMID:24008284

  11. Heading Estimation for Indoor Pedestrian Navigation Using a Smartphone in the Pocket.

    PubMed

    Deng, Zhi-An; Wang, Guofeng; Hu, Ying; Wu, Di

    2015-01-01

    Heading estimation is a central problem for indoor pedestrian navigation using the pervasively available smartphone. For smartphones placed in a pocket, one of the most popular device positions, the essential challenges in heading estimation are the changing device coordinate system and the severe indoor magnetic perturbations. To address these challenges, we propose a novel heading estimation approach based on a rotation matrix and principal component analysis (PCA). Firstly, through a related rotation matrix, we project the acceleration signals into a reference coordinate system (RCS), where a more accurate estimation of the horizontal plane of the acceleration signal is obtained. Then, we utilize PCA over the horizontal plane of acceleration signals for local walking direction extraction. Finally, in order to translate the local walking direction into the global one, we develop a calibration process without requiring noisy compass readings. Besides, a turn detection algorithm is proposed to improve the heading estimation accuracy. Experimental results show that our approach outperforms the traditional uDirect and PCA-based approaches in terms of accuracy and feasibility. PMID:26343679

  12. Heading Estimation for Indoor Pedestrian Navigation Using a Smartphone in the Pocket

    PubMed Central

    Deng, Zhi-An; Wang, Guofeng; Hu, Ying; Wu, Di

    2015-01-01

    Heading estimation is a central problem for indoor pedestrian navigation using the pervasively available smartphone. For smartphones placed in a pocket, one of the most popular device positions, the essential challenges in heading estimation are the changing device coordinate system and the severe indoor magnetic perturbations. To address these challenges, we propose a novel heading estimation approach based on a rotation matrix and principal component analysis (PCA). Firstly, through a related rotation matrix, we project the acceleration signals into a reference coordinate system (RCS), where a more accurate estimation of the horizontal plane of the acceleration signal is obtained. Then, we utilize PCA over the horizontal plane of acceleration signals for local walking direction extraction. Finally, in order to translate the local walking direction into the global one, we develop a calibration process without requiring noisy compass readings. Besides, a turn detection algorithm is proposed to improve the heading estimation accuracy. Experimental results show that our approach outperforms the traditional uDirect and PCA-based approaches in terms of accuracy and feasibility. PMID:26343679

  13. Child and adult pedestrian impact: the influence of vehicle type on injury severity.

    PubMed

    Henary, Basem Y; Crandall, Jeff; Bhalla, Kavi; Mock, Charles N; Roudsari, Bahman S

    2003-01-01

    In the United States, the vehicle fleet is shifting from predominantly passenger cars (automobiles) to SUVs, light trucks, and vans (LTV). This study investigates how pedestrian severe injury and mortality are associated with vehicle type and pedestrian age. The Pedestrian Crash Data Study (PCDS) database for years 1994-1998 was used for a cross-sectional study design. Outcome measures were Injury Severity Score, Maximum Abbreviated Injury Score, Abbreviated Injury Scale, Pedestrian Mortality, Functional Capacity Index and Life Years Lost to Injury. Compared to children, adult pedestrians were more likely to sustain severe injury (OR = 2.81; 95% CI: 1.56-5.06) or mortality (OR = 2.91; 95% CI: 1.10-7.74) when examining all vehicle types. However, after adjusting for vehicle type and impact speed, this association was not statistically significant at p < 0.05. Compared to passenger cars, pedestrians struck by LTV were more likely to have severe injuries (OR = 1.31; 95% CI: 0.88-1.94) or mortality (OR = 1.40; 95% CI: 0.84-2.34) for all pedestrians. Adjusting for pedestrian age, this association was more obvious and significant at lower impact speeds ( < or = 30 km/h); odds ratios of severe injury and mortality were 3.34 (p< 0.01) and 1.87 (p= 0.07), respectively. Adults hit by LTV had the highest risk of injury and mortality. These findings indicate that pedestrian age, vehicle engineering design and impact speed are highly contributing to risks of pedestrian injury and mortality. PMID:12941221

  14. Pattern of pedestrian injuries in the city of Nairobi: implications for urban safety planning.

    PubMed

    Ogendi, Japheths; Odero, Wilson; Mitullah, Winnie; Khayesi, Meleckidzedeck

    2013-10-01

    Pedestrians are overrepresented in road traffic injuries and deaths in Nairobi, the capital city of Kenya, yet little research has been done to provide better understanding of the characteristics of pedestrian injuries. This paper presents the data obtained from road traffic injury admissions to Kenyatta National Hospital (KNH) over a 3-month period starting from 1 June to 31 August 2011. A total of 176 persons involved road traffic injuries in Nairobi were admitted to KNH during this period. Pedestrians comprised the highest (59.1 %) proportion of road traffic injury admissions, followed by motor vehicle passengers (24.4 %) and motor cyclists (9.7 %). Bicyclists and drivers accounted for 5.1 and 1.7 %, respectively. Cars (39.4 %) were the leading category of motorized four-wheeler vehicles that were involved in collisions with pedestrians, followed by matatus (35.5 %). Seventy percent of pedestrians were hit while crossing the road, 10.8 % while standing by the road, and 8.1 % while walking along the road. The highest proportion of pedestrian crashes occurred on Saturdays (25.5 %) and Sundays (16.7 %). Most of the pedestrian injuries (67.7 %) affected the limbs. The paper argues that safety of pedestrians should be a priority in road safety efforts in the city of Nairobi. Urban road safety planners should adopt existing cost-effective interventions to improve the safety of pedestrians such as area-wide traffic calming to limit the speeds of motor vehicles to 30 km/h, providing sidewalks for pedestrians, traffic calming in residential neighborhoods, people-and-not-car-oriented urban road designs, traffic education, and enforcement of traffic regulations. PMID:23430375

  15. Pedestrian Detection and Tracking from Low-Resolution Unmanned Aerial Vehicle Thermal Imagery

    PubMed Central

    Ma, Yalong; Wu, Xinkai; Yu, Guizhen; Xu, Yongzheng; Wang, Yunpeng

    2016-01-01

    Driven by the prominent thermal signature of humans and following the growing availability of unmanned aerial vehicles (UAVs), more and more research efforts have been focusing on the detection and tracking of pedestrians using thermal infrared images recorded from UAVs. However, pedestrian detection and tracking from the thermal images obtained from UAVs pose many challenges due to the low-resolution of imagery, platform motion, image instability and the relatively small size of the objects. This research tackles these challenges by proposing a pedestrian detection and tracking system. A two-stage blob-based approach is first developed for pedestrian detection. This approach first extracts pedestrian blobs using the regional gradient feature and geometric constraints filtering and then classifies the detected blobs by using a linear Support Vector Machine (SVM) with a hybrid descriptor, which sophisticatedly combines Histogram of Oriented Gradient (HOG) and Discrete Cosine Transform (DCT) features in order to achieve accurate detection. This research further proposes an approach for pedestrian tracking. This approach employs the feature tracker with the update of detected pedestrian location to track pedestrian objects from the registered videos and extracts the motion trajectory data. The proposed detection and tracking approaches have been evaluated by multiple different datasets, and the results illustrate the effectiveness of the proposed methods. This research is expected to significantly benefit many transportation applications, such as the multimodal traffic performance measure, pedestrian behavior study and pedestrian-vehicle crash analysis. Future work will focus on using fused thermal and visual images to further improve the detection efficiency and effectiveness. PMID:27023564

  16. Pedestrian Detection and Tracking from Low-Resolution Unmanned Aerial Vehicle Thermal Imagery.

    PubMed

    Ma, Yalong; Wu, Xinkai; Yu, Guizhen; Xu, Yongzheng; Wang, Yunpeng

    2016-01-01

    Driven by the prominent thermal signature of humans and following the growing availability of unmanned aerial vehicles (UAVs), more and more research efforts have been focusing on the detection and tracking of pedestrians using thermal infrared images recorded from UAVs. However, pedestrian detection and tracking from the thermal images obtained from UAVs pose many challenges due to the low-resolution of imagery, platform motion, image instability and the relatively small size of the objects. This research tackles these challenges by proposing a pedestrian detection and tracking system. A two-stage blob-based approach is first developed for pedestrian detection. This approach first extracts pedestrian blobs using the regional gradient feature and geometric constraints filtering and then classifies the detected blobs by using a linear Support Vector Machine (SVM) with a hybrid descriptor, which sophisticatedly combines Histogram of Oriented Gradient (HOG) and Discrete Cosine Transform (DCT) features in order to achieve accurate detection. This research further proposes an approach for pedestrian tracking. This approach employs the feature tracker with the update of detected pedestrian location to track pedestrian objects from the registered videos and extracts the motion trajectory data. The proposed detection and tracking approaches have been evaluated by multiple different datasets, and the results illustrate the effectiveness of the proposed methods. This research is expected to significantly benefit many transportation applications, such as the multimodal traffic performance measure, pedestrian behavior study and pedestrian-vehicle crash analysis. Future work will focus on using fused thermal and visual images to further improve the detection efficiency and effectiveness. PMID:27023564

  17. Child and Adult Pedestrian Impact: The Influence of Vehicle Type on Injury Severity

    PubMed Central

    Henary, Basem Y.; Crandall, Jeff; Bhalla, Kavi; Mock, Charles N.; Roudsari, Bahman S.

    2003-01-01

    In the United States, the vehicle fleet is shifting from predominantly passenger cars (automobiles) to SUVs, light trucks, and vans (LTV). This study investigates how pedestrian severe injury and mortality are associated with vehicle type and pedestrian age. The Pedestrian Crash Data Study (PCDS) database for years 1994–1998 was used for a cross-sectional study design. Outcome measures were Injury Severity Score, Maximum Abbreviated Injury Score, Abbreviated Injury Scale, Pedestrian Mortality, Functional Capacity Index and Life Years Lost to Injury. Compared to children, adult pedestrians were more likely to sustain severe injury (OR = 2.81; 95% CI: 1.56–5.06) or mortality (OR = 2.91; 95% CI: 1.10–7.74) when examining all vehicle types. However, after adjusting for vehicle type and impact speed, this association was not statistically significant at p < 0.05. Compared to passenger cars, pedestrians struck by LTV were more likely to have severe injuries (OR = 1.31; 95% CI: 0.88–1.94) or mortality (OR = 1.40; 95% CI: 0.84–2.34) for all pedestrians. Adjusting for pedestrian age, this association was more obvious and significant at lower impact speeds (≤ 30 km/h); odds ratios of severe injury and mortality were 3.34 (p< 0.01) and 1.87 (p= 0.07), respectively. Adults hit by LTV had the highest risk of injury and mortality. These findings indicate that pedestrian age, vehicle engineering design and impact speed are highly contributing to risks of pedestrian injury and mortality. PMID:12941221

  18. Effects of Mobile Internet Use On College Student Pedestrian Injury Risk

    PubMed Central

    Byington, Katherine W.; Schwebel, David C.

    2012-01-01

    Background College-age individuals have the highest incidence of pedestrian injuries of any age cohort. One factor that might contribute to elevated pedestrian injuries among this age group is injuries incurred while crossing streets distracted by mobile devices. Objectives Examine whether young adult pedestrian safety is compromised while crossing a virtual pedestrian street while distracted using the internet on a mobile “smartphone.” Method A within-subjects design was implemented with 92 young adults. Participants crossed a virtual pedestrian street 20 times, half the time while undistracted and half while completing an email-driven “scavenger hunt” to answer mundane questions using mobile internet on their cell phones. Six measures of pedestrian behavior were assessed during crossings. Participants also reported typical patterns of street crossing and mobile internet use. Results Participants reported using mobile internet with great frequency in daily life, including while walking across streets. In the virtual street environment, pedestrian behavior was greatly altered and generally more risky when participants were distracted by internet use. While distracted, participants waited longer to cross the street (F = 42.37), missed more safe opportunities to cross (F = 42.63), took longer to initiate crossing when a safe gap was available (F = 53.03), looked left and right less often (F = 124.68), spent more time looking away from the road (F = 1959.78), and were more likely to be hit or almost hit by an oncoming vehicle (F = 29.54; all ps< 0.01). Results were retained after controlling for randomized order; participant gender, age, and ethnicity; and both pedestrian habits and mobile internet experience. Conclusion Pedestrian behavior was influenced, and generally considerably riskier, when participants were simultaneously using mobile internet and crossing the street than when crossing the street with no distraction. This finding reinforces the need for

  19. A mixed system modeling two-directional pedestrian flows.

    PubMed

    Goatin, Paola; Mimault, Matthias

    2015-04-01

    In this article, we present a simplified model to describe the dynamics of two groups of pedestrians moving in opposite directions in a corridor. The model consists of a 2 x 2 system of conservation laws of mixed hyperbolic-elliptic type. We study the basic properties of the system to understand why and how bounded oscillations in numerical simulations arise. We show that Lax-Friedrichs scheme ensures the invariance of the domain and we investigate the existence of measure-valued solutions as limit of a subsequence of approximate solutions. PMID:25811441

  20. Pedestrian Navigation Based on a Waist-Worn Inertial Sensor

    PubMed Central

    Alvarez, Juan Carlos; Alvarez, Diego; López, Antonio; González, Rafael C.

    2012-01-01

    We present a waist-worn personal navigation system based on inertial measurement units. The device makes use of the human bipedal pattern to reduce position errors. We describe improved algorithms, based on detailed description of the heel strike biomechanics and its translation to accelerations of the body waist to estimate the periods of zero velocity, the step length, and the heading estimation. The experimental results show that we are able to support pedestrian navigation with the high-resolution positioning required for most applications. PMID:23112614

  1. Optimization of training sequence for DFT-spread DMT signal in optical access network with direct detection utilizing DML.

    PubMed

    Li, Fan; Li, Xinying; Yu, Jianjun; Chen, Lin

    2014-09-22

    We experimentally demonstrated the transmission of 79.86-Gb/s discrete-Fourier-transform spread 32 QAM discrete multi-tone (DFT-spread 32 QAM-DMT) signal over 20-km standard single-mode fiber (SSMF) utilizing directly modulated laser (DML). The experimental results show DFT-spread effectively reduces Peak-to-Average Power Ratio (PAPR) of DMT signal, and also well overcomes narrowband interference and high frequencies power attenuation. We compared different types of training sequence (TS) symbols and found that the optimized TS for channel estimation is the symbol with digital BPSK/QPSK modulation format due to its best performance against optical link noise during channel estimation. PMID:25321766

  2. Training Children in Pedestrian Safety: Distinguishing Gains in Knowledge from Gains in Safe Behavior

    PubMed Central

    McClure, Leslie A.

    2014-01-01

    Pedestrian injuries contribute greatly to child morbidity and mortality. Recent evidence suggests that training within virtual pedestrian environments may improve children’s street crossing skills, but may not convey knowledge about safety in street environments. We hypothesized that (a) children will gain pedestrian safety knowledge via videos/software/internet websites, but not when trained by virtual pedestrian environment or other strategies; (b) pedestrian safety knowledge will be associated with safe pedestrian behavior both before and after training; and (c) increases in knowledge will be associated with increases in safe behavior among children trained individually at streetside locations, but not those trained by means of other strategies. We analyzed data from a randomized controlled trial evaluating pedestrian safety training. We randomly assigned 240 children ages 7–8 to one of four training conditions: videos/software/internet, virtual reality (VR), individualized streetside instruction, or a no-contact control. Both virtual and field simulations of street crossing at 2-lane bi-directional mid-block locations assessed pedestrian behavior at baseline, post-training, and 6-month follow-up. Pedestrian knowledge was assessed orally on all three occasions. Children trained by videos/software/internet, and those trained individually, showed increased knowledge following training relative to children in the other groups (ps < 0.01). Correlations between pedestrian safety knowledge and pedestrian behavior were mostly non-significant. Correlations between change in knowledge and change in behavior from pre- to post-intervention also were non-significant, both for the full sample and within conditions. Children trained using videos/software/internet gained knowledge but did not change their behavior. Children trained individually gained in both knowledge and safer behavior. Children trained virtually gained in safer behavior but not knowledge. If VR is used

  3. Hyperspectral Imaging and Association Phenomenology of Pedestrians in a Cluttered Urban Environment

    NASA Astrophysics Data System (ADS)

    Herweg, Jared A.

    Remote hyperspectral imaging (HSI) has shown promise in several applications such as object detection and tracking. Typically research has focused on large objects, such as vehicles, for tracking due to the spatial resolution of current operational HSI systems. This research seeks to extend the utility of applying HSI to human pedestrian detection using the reflective solar spectral range between 400 - 2500 nm. A phenomenological investigation of a novel scheme to differentiate between pedestrians is studied. By applying the basics of detection theory, this research focuses on being able to differentiate between pedestrians, as well as background materials. Specifically, this research explores the likelihood of detecting and differentiating pedestrians based on four defined subregions comprised of the exposed hair, skin, and the fabrics used for shirts and trousers. The scope of this work encompassed detecting a pedestrian of interest outdoors among other pedestrians in an urban environment consisting of a mixture of asphalt, concrete, grass, and trees. Two unique datasets were created during the course of this effort. One dataset was a collection of fully ground-truthed hyperspectral images of pedestrians in an urban environment. A second dataset was a synthetic rendering of the real-world ground truthed pedestrian scene developed using the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model. Subregion separability analysis results, using spectral reflectance data, provided strong evidence that combining the observable spectral features of detectable subregions is a viable means of distinguishing between pedestrians. Further analysis using real-world HSI data demonstrated that the detection and classification of the pedestrian subregions when changes in illumination, location, and background occur within the field of view of a hyperspectral sensor is achievable with a greater than 60% accuracy. In addition to the direct detection and association

  4. Two cascaded SOAs used as intensity modulators for adaptively modulated optical OFDM signals in optical access networks.

    PubMed

    Hamié, Ali; Hamzé, Mohamad; Taki, Haidar; Makouk, Layaly; Sharaiha, Ammar; Alaeddine, Ali; Al Housseini, Ali; Giacoumidis, Elias; Tang, J M

    2014-06-30

    Detailed theoretical and numerical investigations of the transmission performance of adaptively modulated optical orthogonal frequency division multiplexed (AMOOFDM) signals are undertaken, for the first time, in optical amplification and chromatic dispersion (CD) compensation free single mode fiber (SMF) intensity-modulated and direct-detection (IMDD) systems using two cascaded semiconductor optical amplifiers in a counterpropagating configuration as an intensity modulator (TC-SOA-CC-IM). A theoretical model describing the characteristics of this configuration is developed. Extensive performance comparisons are also made between the TC-SOA-CC and the single SOA intensity modulators. It is shown that, the TC-SOA-CC reaches its strongly saturated region using a lower input optical power much faster than the single SOA resulting in significantly reduced effective carrier lifetime and thus wide TC-SOA-CC bandwidths. It is shown that at low input optical power, we can increase the signal line rate almost 115% which will be more than twice the transmission performance offered by single SOA. In addition, the TC-SOA-CC-IM is capable of supporting signal line rates higher than corresponding to the SOA-IM by using 10dB lower input optical powers. For long transmission distance, the TC-SOA-CC-IM has much stronger CD compensation capability compared to the SOA-IM. In addition the use of TC-SOA-CC-IM is more effective regarding the capability to benefit from the CD compensation for shorter distances starting at 60km SMF, whilst for the SOA-IM starting at 90km. PMID:24977835

  5. Application of radar to detect pedestrian workers near mining equipment.

    PubMed

    Ruff, T M

    2001-08-01

    Between 1990 and 1996, 133 accidents occurred and 23 mine workers were killed when haulage trucks used in surface mines collided with another smaller vehicle, a mine structure, or a pedestrian worker. These accidents were caused by a lack of visibility from the cab of the truck. Similar accidents are common with other types of equipment, such as front-end loaders and shovels. There are several methods for improving the operator's awareness of objects or people around the equipment including improved mirror designs, video cameras, and sensor technologies. Researchers at the National Institute for Occupational Safety and Health (NIOSH) are evaluating collision warning systems that are based on radar technology. These systems are mounted on the mining equipment to monitor one or more of the blind areas. An alarm is provided to the operator if an object or person enters the radar's detection area. Tests consisted of mounting the systems on a 50-ton-capacity truck typically used in quarries and a 240-ton-capacity truck used at a surface mine. This article summarizes the test procedure and results of evaluations of several off-the-shelf and prototype radar systems. False alarm rates and reliable detection zones for pedestrians were recorded for various mounting configurations on the rear of the trucks. Mounting radar systems on large equipment presents several challenges; however, the technology does show promise for this application. PMID:11504357

  6. Sole parenthood and the risk of child pedestrian injury.

    PubMed

    Roberts, I

    1994-12-01

    Children of sole parents have the worst mortality record of all social groups. Road vehicle related injuries account for a large part of their excess mortality. In this case-control study the association between sole parent status and the risk of child pedestrian injury was examined. Cases (n = 258) were children killed or hospitalized as a result of a pedestrian injury in the Auckland region over a period of 2 years and 2 months. Controls were a random sample of the child population. The children of sole parents were at a significantly increased risk of injury (odds ratio = 1.57; 95% confidence interval (CI) 1.09, 2.27). However, there was a striking difference in the effect of sole parent status according to ethnic group. Among European families, sole parenthood was associated with a greatly increased risk of injury (OR = 3.13; 95%CI 1.84, 5.31), whereas in Pacific Island families sole parenthood was associated with a significant protective effect (OR = 0.40; 95%CI 0.18, 0.89). The protective effect of sole parent status in Pacific Island families may reflect the beneficial effects of the social support provided by extended family networks. Children of sole parents in the context of the nuclear family may be particularly vulnerable. PMID:7865268

  7. Pedestrian Detection with Spatially Pooled Features and Structured Ensemble Learning.

    PubMed

    Paisitkriangkrai, Sakrapee; Shen, Chunhua; Hengel, Anton van den

    2016-06-01

    Many typical applications of object detection operate within a prescribed false-positive range. In this situation the performance of a detector should be assessed on the basis of the area under the ROC curve over that range, rather than over the full curve, as the performance outside the prescribed range is irrelevant. This measure is labelled as the partial area under the ROC curve (pAUC). We propose a novel ensemble learning method which achieves a maximal detection rate at a user-defined range of false positive rates by directly optimizing the partial AUC using structured learning. In addition, in order to achieve high object detection performance, we propose a new approach to extracting low-level visual features based on spatial pooling. Incorporating spatial pooling improves the translational invariance and thus the robustness of the detection process. Experimental results on both synthetic and real-world data sets demonstrate the effectiveness of our approach, and we show that it is possible to train state-of-the-art pedestrian detectors using the proposed structured ensemble learning method with spatially pooled features. The result is the current best reported performance on the Caltech-USA pedestrian detection dataset. PMID:26336118

  8. Vector Graph Assisted Pedestrian Dead Reckoning Using an Unconstrained Smartphone

    PubMed Central

    Qian, Jiuchao; Pei, Ling; Ma, Jiabin; Ying, Rendong; Liu, Peilin

    2015-01-01

    The paper presents a hybrid indoor positioning solution based on a pedestrian dead reckoning (PDR) approach using built-in sensors on a smartphone. To address the challenges of flexible and complex contexts of carrying a phone while walking, a robust step detection algorithm based on motion-awareness has been proposed. Given the fact that step length is influenced by different motion states, an adaptive step length estimation algorithm based on motion recognition is developed. Heading estimation is carried out by an attitude acquisition algorithm, which contains a two-phase filter to mitigate the distortion of magnetic anomalies. In order to estimate the heading for an unconstrained smartphone, principal component analysis (PCA) of acceleration is applied to determine the offset between the orientation of smartphone and the actual heading of a pedestrian. Moreover, a particle filter with vector graph assisted particle weighting is introduced to correct the deviation in step length and heading estimation. Extensive field tests, including four contexts of carrying a phone, have been conducted in an office building to verify the performance of the proposed algorithm. Test results show that the proposed algorithm can achieve sub-meter mean error in all contexts. PMID:25738763

  9. On the hazard of quiet vehicles to pedestrians and drivers.

    PubMed

    Wogalter, Michael S; Lim, Raymond W; Nyeste, Patrick G

    2014-09-01

    The need to produce more efficient and less polluting vehicles has encouraged mass production of alternative energy vehicles, such as hybrid and electric cars. Many of these vehicles are capable of very quiet operation. While reducing noise pollution is desirable, quieter vehicles could negatively affect pedestrian safety because of reduced sound cues compared to louder internal combustion engines. Three studies were performed to investigate people's concern about this issue. In Study 1, a questionnaire completed by 378 people showed substantial positive interest in quiet hybrid and electric cars. However, they also indicated concern about the reduced auditory cues of quiet vehicles. In Study 2, 316 participants rated 14 sounds that could be potentially added to quiet alternative-energy vehicles. The data showed that participants did not want annoying sounds, but preferred adding "engine" and "hum" sounds relative to other types of sounds. In Study 3, 24 persons heard and rated 18 actual sounds within 6 categories that were added to a video of a hybrid vehicle driving by. The sounds most preferred were "engine" followed by "white noise" and "hum". Implications for adding sounds to facilitate pedestrians' detection of moving vehicles and for aiding drivers' awareness of speed are discussed. PMID:24035347

  10. Jamming transitions in force-based models for pedestrian dynamics.

    PubMed

    Chraibi, Mohcine; Ezaki, Takahiro; Tordeux, Antoine; Nishinari, Katsuhiro; Schadschneider, Andreas; Seyfried, Armin

    2015-10-01

    Force-based models describe pedestrian dynamics in analogy to classical mechanics by a system of second order ordinary differential equations. By investigating the linear stability of two main classes of forces, parameter regions with unstable homogeneous states are identified. In this unstable regime it is then checked whether phase transitions or stop-and-go waves occur. Results based on numerical simulations show, however, that the investigated models lead to unrealistic behavior in the form of backwards moving pedestrians and overlapping. This is one reason why stop-and-go waves have not been observed in these models. The unrealistic behavior is not related to the numerical treatment of the dynamic equations but rather indicates an intrinsic problem of this model class. Identifying the underlying generic problems gives indications how to define models that do not show such unrealistic behavior. As an example we introduce a force-based model which produces realistic jam dynamics without the appearance of unrealistic negative speeds for empirical desired walking speeds. PMID:26565291

  11. The exposure of young children to accident risk as pedestrians.

    PubMed Central

    Routledge, D. A.; Repetto-Wright, R.; Howarth, C. I.

    1996-01-01

    Pedestrian road accidents show a marked peak for children aged 5, 6 and 7 years with boys twice as involved as girls at these ages. Howarth et al (1974) described a framework in which measures of exposure were defined and related to the accident statistics to obtain estimates of absolute levels of risk for different categories of pedestrian in different traffic situations. The present paper describes a survey of children's exposure carried out to provide suitable data for this quantitative analysis. We interviewed a representative sample of Nottingham schoolchildren about their journeys in the previous 24 hours and recorded the number of roads crossed and the traffic densities of these roads. The measures of exposure obtained are presented in relation to the accompaniment of children on their journeys, the type of area in which they live, and time of day. Risk was assessed by relating exposure measures both to the national and local accident statistics. The analysis provides estimates of the risk to children of different ages and sex in their normal pattern of road crossing and in crossing roads of different traffic density and indicates that the accident statistics alone considerably underestimate the degree of risk to children under the age of eight. Interviews with a sample of the parents of the children suggest that children may provide a more accurate measure of their exposure than do their parents. PMID:9346080

  12. Pedestrian evacuation at the subway station under fire

    NASA Astrophysics Data System (ADS)

    Xiao-Xia, Yang; Hai-Rong, Dong; Xiu-Ming, Yao; Xu-Bin, Sun

    2016-04-01

    With the development of urban rail transit, ensuring the safe evacuation of pedestrians at subway stations has become an important issue in the case of an emergency such as a fire. This paper chooses the platform of line 4 at the Beijing Xuanwumen subway station to study the emergency evacuation process under fire. Based on the established platform, effects of the fire dynamics, different initial pedestrian densities, and positions of fire on evacuation are investigated. According to simulation results, it is found that the fire increases the air temperature and the smoke density, and decreases pedestrians’ visibility and walking velocity. Also, there is a critical initial density at the platform if achieving a safe evacuation within the required 6 minutes. Furthermore, different positions of fire set in this paper have little difference on crowd evacuation if the fire is not large enough. The suggestions provided in this paper are helpful for the subway operators to prevent major casualties. Project supported by the National Natural Science Foundation of China (Grant Nos. 61322307 and 61233001).

  13. Vector graph assisted pedestrian dead reckoning using an unconstrained smartphone.

    PubMed

    Qian, Jiuchao; Pei, Ling; Ma, Jiabin; Ying, Rendong; Liu, Peilin

    2015-01-01

    The paper presents a hybrid indoor positioning solution based on a pedestrian dead reckoning (PDR) approach using built-in sensors on a smartphone. To address the challenges of flexible and complex contexts of carrying a phone while walking, a robust step detection algorithm based on motion-awareness has been proposed. Given the fact that step length is influenced by different motion states, an adaptive step length estimation algorithm based on motion recognition is developed. Heading estimation is carried out by an attitude acquisition algorithm, which contains a two-phase filter to mitigate the distortion of magnetic anomalies. In order to estimate the heading for an unconstrained smartphone, principal component analysis (PCA) of acceleration is applied to determine the offset between the orientation of smartphone and the actual heading of a pedestrian. Moreover, a particle filter with vector graph assisted particle weighting is introduced to correct the deviation in step length and heading estimation. Extensive field tests, including four contexts of carrying a phone, have been conducted in an office building to verify the performance of the proposed algorithm. Test results show that the proposed algorithm can achieve sub-meter mean error in all contexts. PMID:25738763

  14. Detecting carried objects from sequences of walking pedestrians.

    PubMed

    Damen, Dima; Hogg, David

    2012-06-01

    This paper proposes a method for detecting objects carried by pedestrians, such as backpacks and suitcases, from video sequences. In common with earlier work [14], [16] on the same problem, the method produces a representation of motion and shape (known as a temporal template) that has some immunity to noise in foreground segmentations and phase of the walking cycle. Our key novelty is for carried objects to be revealed by comparing the temporal templates against view-specific exemplars generated offline for unencumbered pedestrians. A likelihood map of protrusions, obtained from this match, is combined in a Markov random field for spatial continuity, from which we obtain a segmentation of carried objects using the MAP solution. We also compare the previously used method of periodicity analysis to distinguish carried objects from other protrusions with using prior probabilities for carried-object locations relative to the silhouette. We have reimplemented the earlier state-of-the-art method [14] and demonstrate a substantial improvement in performance for the new method on the PETS2006 data set. The carried-object detector is also tested on another outdoor data set. Although developed for a specific problem, the method could be applied to the detection of irregularities in appearance for other categories of object that move in a periodic fashion. PMID:22516646

  15. Deciphering the Crowd: Modeling and Identification of Pedestrian Group Motion

    PubMed Central

    Yücel, Zeynep; Zanlungo, Francesco; Ikeda, Tetsushi; Miyashita, Takahiro; Hagita, Norihiro

    2013-01-01

    Associating attributes to pedestrians in a crowd is relevant for various areas like surveillance, customer profiling and service providing. The attributes of interest greatly depend on the application domain and might involve such social relations as friends or family as well as the hierarchy of the group including the leader or subordinates. Nevertheless, the complex social setting inherently complicates this task. We attack this problem by exploiting the small group structures in the crowd. The relations among individuals and their peers within a social group are reliable indicators of social attributes. To that end, this paper identifies social groups based on explicit motion models integrated through a hypothesis testing scheme. We develop two models relating positional and directional relations. A pair of pedestrians is identified as belonging to the same group or not by utilizing the two models in parallel, which defines a compound hypothesis testing scheme. By testing the proposed approach on three datasets with different environmental properties and group characteristics, it is demonstrated that we achieve an identification accuracy of 87% to 99%. The contribution of this study lies in its definition of positional and directional relation models, its description of compound evaluations, and the resolution of ambiguities with our proposed uncertainty measure based on the local and global indicators of group relation. PMID:23344382

  16. Jamming transitions in force-based models for pedestrian dynamics

    NASA Astrophysics Data System (ADS)

    Chraibi, Mohcine; Ezaki, Takahiro; Tordeux, Antoine; Nishinari, Katsuhiro; Schadschneider, Andreas; Seyfried, Armin

    2015-10-01

    Force-based models describe pedestrian dynamics in analogy to classical mechanics by a system of second order ordinary differential equations. By investigating the linear stability of two main classes of forces, parameter regions with unstable homogeneous states are identified. In this unstable regime it is then checked whether phase transitions or stop-and-go waves occur. Results based on numerical simulations show, however, that the investigated models lead to unrealistic behavior in the form of backwards moving pedestrians and overlapping. This is one reason why stop-and-go waves have not been observed in these models. The unrealistic behavior is not related to the numerical treatment of the dynamic equations but rather indicates an intrinsic problem of this model class. Identifying the underlying generic problems gives indications how to define models that do not show such unrealistic behavior. As an example we introduce a force-based model which produces realistic jam dynamics without the appearance of unrealistic negative speeds for empirical desired walking speeds.

  17. Pedestrian movement analysis in transfer station corridor: Velocity-based and acceleration-based

    NASA Astrophysics Data System (ADS)

    Ji, Xiangfeng; Zhang, Jian; Hu, Yongkai; Ran, Bin

    2016-05-01

    In this paper, pedestrians are classified into aggressive and conservative ones by their temper. Aggressive pedestrians' walking through crowd in transfer station corridor is analyzed. Treating pedestrians as particles, this paper uses the modified social force model (MSFM) as the building block, where forces involve self-driving force, repulsive force and friction force. The proposed model in this paper is a discrete model combining the MSFM and cellular automata (CA) model, where the updating rules of the CA are redefined with MSFM. Due to the continuity of values generated by the MSFM, we use the fuzzy logic to discretize the continuous values into cells pedestrians can move in one step. With the observation that stimulus around pedestrians influences their acceleration directly, an acceleration-based movement model is presented, compared to the generally reviewed velocity-based movement model. In the acceleration-based model, a discretized version of kinematic equation is presented based on the acceleration discretized with fuzzy logic. In real life, some pedestrians would rather keep their desired speed and this is also mimicked in this paper, which is called inertia. Compared to the simple triangular membership function, a trapezoidal membership function and a piecewise linear membership function are used to capture pedestrians' inertia. With the trapezoidal and the piecewise linear membership function, many overlapping scenarios should be carefully handled and Dubois and Prade's four-index method is used to completely describe the relative relationship of fuzzy quantities. Finally, a simulation is constructed to demonstrate the effect of our model.

  18. Pedestrian simulation and distribution in urban space based on visibility analysis and agent simulation

    NASA Astrophysics Data System (ADS)

    Ying, Shen; Li, Lin; Gao, Yurong

    2009-10-01

    Spatial visibility analysis is the important direction of pedestrian behaviors because our visual conception in space is the straight method to get environment information and navigate your actions. Based on the agent modeling and up-tobottom method, the paper develop the framework about the analysis of the pedestrian flow depended on visibility. We use viewshed in visibility analysis and impose the parameters on agent simulation to direct their motion in urban space. We analyze the pedestrian behaviors in micro-scale and macro-scale of urban open space. The individual agent use visual affordance to determine his direction of motion in micro-scale urban street on district. And we compare the distribution of pedestrian flow with configuration in macro-scale urban environment, and mine the relationship between the pedestrian flow and distribution of urban facilities and urban function. The paper first computes the visibility situations at the vantage point in urban open space, such as street network, quantify the visibility parameters. The multiple agents use visibility parameters to decide their direction of motion, and finally pedestrian flow reach to a stable state in urban environment through the simulation of multiple agent system. The paper compare the morphology of visibility parameters and pedestrian distribution with urban function and facilities layout to confirm the consistence between them, which can be used to make decision support in urban design.

  19. Pedestrian dynamics in single-file movement of crowd with different age compositions.

    PubMed

    Cao, Shuchao; Zhang, Jun; Salden, Daniel; Ma, Jian; Shi, Chang'an; Zhang, Ruifang

    2016-07-01

    An aging population is bringing new challenges to the management of escape routes and facility design in many countries. This paper investigates pedestrian movement properties of crowd with different age compositions. Three pedestrian groups are considered: young student group, old people group, and mixed group. It is found that traffic jams occur more frequently in mixed group due to the great differences of mobilities and self-adaptive abilities among pedestrians. The jams propagate backward with a velocity 0.4m/s for global density ρ_{g}≈1.75m^{-1} and 0.3m/s for ρ_{g}>2.3m^{-1}. The fundamental diagrams of the three groups are obviously different from each other and cannot be unified into one diagram by direct nondimensionalization. Unlike previous studies, three linear regimes in mixed group but only two regimes in young student group are observed in the headway-velocity relation, which is also verified in the fundamental diagram. Different ages and mobilities of pedestrians in a crowd cause the heterogeneity of system and influence the properties of pedestrian dynamics significantly. It indicates that the density is not the only factor leading to jams in pedestrian traffic. The composition of crowd has to be considered in understanding pedestrian dynamics and facility design. PMID:27575153

  20. Measuring accident risk exposure for pedestrians in different micro-environments.

    PubMed

    Lassarre, Sylvain; Papadimitriou, Eleonora; Yannis, George; Golias, John

    2007-11-01

    Pedestrians are mainly exposed to the risk of road accident when crossing a road in urban areas. Traditionally in the road safety field, the risk of accident for pedestrian is estimated as a rate of accident involvement per unit of time spent on the road network. The objective of this research is to develop an approach of accident risk based on the concept of risk exposure used in environmental epidemiology, such as in the case of exposure to pollutants. This type of indicator would be useful for comparing the effects of urban transportation policy scenarios on pedestrian safety. The first step is to create an indicator of pedestrians' exposure, which is based on motorised vehicles' "concentration" by lane and also takes account of traffic speed and time spent to cross. This is applied to two specific micro-environments: junctions and mid-block locations. A model of pedestrians' crossing behaviour along a trip is then developed, based on a hierarchical choice between junctions and mid-block locations and taking account of origin and destination, traffic characteristics and pedestrian facilities. Finally, a complete framework is produced for modelling pedestrians' exposure in the light of their crossing behaviour. The feasibility of this approach is demonstrated on an artificial network and a first set of results is obtained from the validation of the models in observational studies. PMID:17920847

  1. Pedestrian dynamics in single-file movement of crowd with different age compositions

    NASA Astrophysics Data System (ADS)

    Cao, Shuchao; Zhang, Jun; Salden, Daniel; Ma, Jian; Shi, Chang'an; Zhang, Ruifang

    2016-07-01

    An aging population is bringing new challenges to the management of escape routes and facility design in many countries. This paper investigates pedestrian movement properties of crowd with different age compositions. Three pedestrian groups are considered: young student group, old people group, and mixed group. It is found that traffic jams occur more frequently in mixed group due to the great differences of mobilities and self-adaptive abilities among pedestrians. The jams propagate backward with a velocity 0.4 m /s for global density ρg≈1.75 m-1 and 0.3 m /s for ρg>2.3 m-1 . The fundamental diagrams of the three groups are obviously different from each other and cannot be unified into one diagram by direct nondimensionalization. Unlike previous studies, three linear regimes in mixed group but only two regimes in young student group are observed in the headway-velocity relation, which is also verified in the fundamental diagram. Different ages and mobilities of pedestrians in a crowd cause the heterogeneity of system and influence the properties of pedestrian dynamics significantly. It indicates that the density is not the only factor leading to jams in pedestrian traffic. The composition of crowd has to be considered in understanding pedestrian dynamics and facility design.

  2. Pedestrian fatality risk in accidents at unsignalized zebra crosswalks in Poland.

    PubMed

    Olszewski, Piotr; Szagała, Piotr; Wolański, Maciej; Zielińska, Anna

    2015-11-01

    Poland has the second worst pedestrian fatality rate in the European Union. In the years 2007-2012, 9101 pedestrians were killed and 71328 injured on Polish roads. Almost 30% of pedestrian injury accidents took place at unsignalized zebra crosswalks. Based on police accident database, the worst problem in terms of numbers of fatalities occurs in built-up areas, on two-way undivided roads and at mid-block locations. Especially at risk are older people - almost 73% of pedestrians killed were 55 years or older. In order to show the effect of various factors on pedestrian fatality risk, a binary logit model with interaction terms was developed. The model shows that the following factors increase the probability of pedestrian's death at unsignalized zebra crosswalks: darkness, especially with no street lighting, divided road, two-way road, non built-up area, mid-block crosswalk location and summer time period. Speed limit is a crucial factor: probability of death increases by 37% with every 10km/h rise in the speed limit. Fatality risk increases also with victim's age and is higher for male pedestrians. PMID:26322732

  3. Biomechanically inspired modelling of pedestrian-induced forces on laterally oscillating structures

    NASA Astrophysics Data System (ADS)

    Bocian, M.; Macdonald, J. H. G.; Burn, J. F.

    2012-07-01

    Despite considerable interest among engineers and scientists, bi-directional interaction between walking pedestrians and lively bridges has still not been well understood. In an attempt to bridge this gap a biomechanically inspired model of the human response to lateral bridge motion is presented and explored. The simple inverted pendulum model captures the key features of pedestrian lateral balance and the resulting forces on the structure. The forces include self-excited components that can be effectively modelled as frequency-dependent added damping and mass to the structure. The results of numerical simulations are in reasonable agreement with recent experimental measurements of humans walking on a laterally oscillating treadmill, and in very good agreement with measurements on full-scale bridges. In contrast to many other models of lateral pedestrian loading, synchronisation with the bridge motion is not involved. A parametric study of the model is conducted, revealing that as pedestrians slow down as a crowd becomes more dense, their resulting lower pacing rates generate larger self-excited forces. For typical pedestrian parameters, the potential to generate negative damping arises for any lateral bridge vibration frequency above 0.43 Hz, depending on the walking frequency. Stability boundaries of the combined pedestrian-structure system are presented in terms of the structural damping ratio and pedestrian-to-bridge mass ratio, revealing complex relations between damping demand and bridge and pedestrian frequencies, due to the added mass effect. Finally it is demonstrated that the model can produce simultaneous self-excited forces on multiple structural modes, and a realistic full simulation of a large number of pedestrians, walking randomly and interacting with a bridge, produces structural behaviour in very good agreement with site observations.

  4. Evacuation of pedestrians from a single room by using snowdrift game theories

    NASA Astrophysics Data System (ADS)

    Shi, Dong-Mei; Wang, Bing-Hong

    2013-02-01

    Game theory is introduced to simulate the complicated interaction relations among the conflicting pedestrians in a pedestrian flow system, which is defined on a square lattice with the parallel update rule. Modified on the traditional lattice gas model, each pedestrian can move to not only an empty site, but also an occupied site. It is found that each individual chooses its neighbor randomly and occupies the site with the probability W(x→y)=(1)/(1+exp[-(Px-Ux)/κ]), where Px is the x's payoff representing his personal energy, and Ux is the average payoff of its neighborhood indicating the potential well energy if he stays. Two types of pedestrians are considered, and they interact with their neighbors following the payoff matrix of snowdrift game theory. The cost-to-benefit ratio r=c/(2b-c) (where b is the perfect payoff and c is the labor cost) represents the fear index of the pedestrians in this model. It is found that there exists a moderate value of r leading to the shortest escape time, and the situation for large values of r is better than that for small ones in general. In addition, the pedestrian flow system always arrives at a consistent state in which the two types of walkers have the same number and evolve by the same law irrespectively of the parameters, which can be interpreted as the self-organization effect of pedestrian flow. It is also proven that the time point of the onset of the steady state is unrelated to the scale of the pedestrians and the square lattice. Meanwhile, the system exhibits different dynamics before reaching the consistent state: the number of the two types of walkers oscillates when PC>0.5 (i.e., probability to change the present strategy), while no oscillation happens for PC≤0.5. Finally, it is shown that a smaller density of pedestrians ρ induces a shorter average escape time.

  5. Modelling framework for dynamic interaction between multiple pedestrians and vertical vibrations of footbridges

    NASA Astrophysics Data System (ADS)

    Venuti, Fiammetta; Racic, Vitomir; Corbetta, Alessandro

    2016-09-01

    After 15 years of active research on the interaction between moving people and civil engineering structures, there is still a lack of reliable models and adequate design guidelines pertinent to vibration serviceability of footbridges due to multiple pedestrians. There are three key issues that a new generation of models should urgently address: pedestrian "intelligent" interaction with the surrounding people and environment, effect of human bodies on dynamic properties of unoccupied structure and inter-subject and intra-subject variability of pedestrian walking loads. This paper presents a modelling framework of human-structure interaction in the vertical direction which addresses all three issues. The framework comprises two main models: (1) a microscopic model of multiple pedestrian traffic that simulates time varying position and velocity of each individual pedestrian on the footbridge deck, and (2) a coupled dynamic model of a footbridge and multiple walking pedestrians. The footbridge is modelled as a SDOF system having the dynamic properties of the unoccupied structure. Each walking pedestrian in a group or crowd is modelled as a SDOF system with an adjacent stochastic vertical force that moves along the footbridge following the trajectory and the gait pattern simulated by the microscopic model of pedestrian traffic. Performance of the suggested modelling framework is illustrated by a series of simulated vibration responses of a virtual footbridge due to light, medium and dense pedestrian traffic. Moreover, the Weibull distribution is shown to fit well the probability density function of the local peaks in the acceleration response. Considering the inherent randomness of the crowd, this makes it possible to determine the probability of exceeding any given acceleration value of the occupied bridge.

  6. Mathematical Modeling of Pedestrian Flows Using Cellular Automata and Dynamic Stepsizing

    NASA Astrophysics Data System (ADS)

    Bärwolff, Günter; Chen, Minjie; Schwandt, Hartmut

    2007-09-01

    We present a two-dimensional automaton model to simulate pedestrian flows. In this model, pedestrians may be allocated have preassigned or randomly chosen starting points and destinations, and they may get influenced by additional repelling or indicating factors. Interior walls and other obstacles can be abstracted as repellors. We apply Bresenham's algorithm [1] of line rastering to calculate the ideal forward step which a single pedestrian may take on a two-dimensional grid. We introduce a flexible choice of step sizes to improve the basic algorithm.

  7. Preventing motor vehicle-occupant and pedestrian injuries in children and adolescents.

    PubMed

    Wilson, M H; Shock, S

    1993-06-01

    Injuries to young motor vehicle occupants and pedestrians continue to be a leading cause of childhood and adolescent mortality and morbidity. Recent articles relevant to childhood traffic injuries are reviewed here. Topics include infant passengers traveling on lap, effectiveness of seat belts for 4 to 14 year olds, passengers riding in the back of pickup trucks, and characteristics of young drivers. Socioecologic and geographic factors in pedestrian injuries are also discussed, along with parents' expectations of their children's street-crossing skills, the efficacy of a school-based pedestrian training program, and children's abilities to estimate safe intervals between traffic when crossing streets. PMID:8374646

  8. Pedestrian flow-path modeling to support tsunami evacuation and disaster relief planning in the U.S. Pacific Northwest

    USGS Publications Warehouse

    Wood, Nathan J.; Jones, Jeanne M.; Schmidtlein, Mathew; Schelling, John; Frazier, T.

    2016-01-01

    Successful evacuations are critical to saving lives from future tsunamis. Pedestrian-evacuation modeling related to tsunami hazards primarily has focused on identifying areas and the number of people in these areas where successful evacuations are unlikely. Less attention has been paid to identifying evacuation pathways and population demand at assembly areas for at-risk individuals that may have sufficient time to evacuate. We use the neighboring coastal communities of Hoquiam, Aberdeen, and Cosmopolis (Washington, USA) and the local tsunami threat posed by Cascadia subduction zone earthquakes as a case study to explore the use of geospatial, least-cost-distance evacuation modeling for supporting evacuation outreach, response, and relief planning. We demonstrate an approach that uses geospatial evacuation modeling to (a) map the minimum pedestrian travel speeds to safety, the most efficient paths, and collective evacuation basins, (b) estimate the total number and demographic description of evacuees at predetermined assembly areas, and (c) determine which paths may be compromised due to earthquake-induced ground failure. Results suggest a wide range in the magnitude and type of evacuees at predetermined assembly areas and highlight parts of the communities with no readily accessible assembly area. Earthquake-induced ground failures could obstruct access to some assembly areas, cause evacuees to reroute to get to other assembly areas, and isolate some evacuees from relief personnel. Evacuation-modeling methods and results discussed here have implications and application to tsunami-evacuation outreach, training, response procedures, mitigation, and long-term land use planning to increase community resilience.

  9. Predictors of road crossing safety in pedestrians with Parkinson's disease.

    PubMed

    Lin, Chin-Hsien; Ou, Yang-Kun; Wu, Ruey-Meei; Liu, Yung-Ching

    2013-03-01

    Road-crossing safety is an important issue in an aging society. Information regarding the risk of crossing the street to pedestrians with Parkinson's disease (PD) is limited. To assess the risk and predictors of unsafe crossing behaviors in patients with PD, we compared 31 pedestrians with mild-to-moderate PD to 50 age/gender/education-matched controls using a battery of cognitive, visual, and motor tests. With a simulated simple street-crossing situation, we determined the remaining time and safety margin for each participant in different traffic situations, including variable motor vehicle speed, time gap, and time of the day. Odds ratios (ORs) were estimated by logistic regression models. We found that pedestrians with PD were more vulnerable to traffic accidents than controls (OR 1.61 [1.28-2.02], P=0.01). The risk of crossing road correlated in a dose-dependent manner with the severity of PD, based on both Hoehn and Yahr (H&Y) stages and unified Parkinson's disease rating scale (UPDRS) motor scores (OR 1.13 for each increasing point of UPDSR, P<0.01). Among PD patients, scores of clock drawing test (OR 0.8 [0.74-0.88], P<0.01) and visual form discrimination (OR 1.14 [1.07-1.22], P<0.01) predicted worsening of safety errors, rather than executive function. Environmental factors, such as fast approaching motor vehicle speed (OR 4.50 [2.92-6.95], P<0.01), short time gap (OR 45.98 [27.04-78.18], P<0.01), and time of day (OR 4.45 [3.11-6.36], P<0.01) also affected road-crossing safety. Future large sample studies are needed to confirm our findings. Training programs or portable stimulator devices that compensate for the visual-spatial disabilities of PD patients are required to improve road safety for PD patients. PMID:23262459

  10. Multimodal injury risk analysis of road users at signalized and non-signalized intersections.

    PubMed

    Strauss, Jillian; Miranda-Moreno, Luis F; Morency, Patrick

    2014-10-01

    This paper proposes a multimodal approach to study safety at intersections by simultaneously analysing the safety and flow outcomes for both motorized and non-motorized traffic. This study uses an extensive inventory of signalized and non-signalized intersections on the island of Montreal, Quebec, Canada, containing disaggregate motor-vehicle, cyclist and pedestrian flows, injury data, geometric design, traffic control and built environment characteristics in the vicinity of each intersection. Bayesian multivariate Poisson models are used to analyze the injury and traffic flow outcomes and to develop safety performance functions for each mode at both facilities. After model calibration, contributing injury frequency factors are identified. Injury frequency and injury risk measures are then generated to carry out a comparative study to identify which mode is at greatest risk at intersections in Montreal. Among other results, this study identified the significant effect that motor-vehicle traffic imposes on cyclist and pedestrian injury occurrence. Motor-vehicle traffic is the main risk determinant for all injury and intersection types. This highlights the need for safety improvements for cyclists and pedestrians who are, on average, at 14 and12 times greater risk than motorists, respectively, at signalized intersections. Aside from exposure measures, this work also identifies some geometric design and built environment characteristics affecting injury occurrence for cyclists, pedestrians and motor-vehicle occupants. PMID:24945759

  11. A Microscopic “Social Norm” Model to Obtain Realistic Macroscopic Velocity and Density Pedestrian Distributions

    PubMed Central

    Zanlungo, Francesco; Ikeda, Tetsushi; Kanda, Takayuki

    2012-01-01

    We propose a way to introduce in microscopic pedestrian models a “social norm” in collision avoiding and overtaking, i.e. the tendency, shared by pedestrians belonging to the same culture, to avoid collisions and perform overtaking in a preferred direction. The “social norm” is implemented, regardless of the specific collision avoiding model, as a rotation in the perceived velocity vector of the opponent at the moment of computation of the collision avoiding strategy, and justified as an expectation that the opponent will follow the same “social norm” (for example a tendency to avoid on the left and overtake on the right, as proposed in this work for Japanese pedestrians). By comparing with real world data, we show that the introduction of this norm allows for a better reproduction of macroscopic pedestrian density and velocity patterns. PMID:23227202

  12. Generating Pedestrian Trajectories Consistent with the Fundamental Diagram Based on Physiological and Psychological Factors

    PubMed Central

    Narang, Sahil; Best, Andrew; Curtis, Sean; Manocha, Dinesh

    2015-01-01

    Pedestrian crowds often have been modeled as many-particle system including microscopic multi-agent simulators. One of the key challenges is to unearth governing principles that can model pedestrian movement, and use them to reproduce paths and behaviors that are frequently observed in human crowds. To that effect, we present a novel crowd simulation algorithm that generates pedestrian trajectories that exhibit the speed-density relationships expressed by the Fundamental Diagram. Our approach is based on biomechanical principles and psychological factors. The overall formulation results in better utilization of free space by the pedestrians and can be easily combined with well-known multi-agent simulation techniques with little computational overhead. We are able to generate human-like dense crowd behaviors in large indoor and outdoor environments and validate the results with captured real-world crowd trajectories. PMID:25875932

  13. The influence of emotional facial expressions on gaze-following in grouped and solitary pedestrians

    PubMed Central

    Gallup, Andrew C.; Chong, Andrew; Kacelnik, Alex; Krebs, John R.; Couzin, Iain D.

    2014-01-01

    The mechanisms contributing to collective attention in humans remain unclear. Research indicates that pedestrians utilise the gaze direction of others nearby to acquire environmentally relevant information, but it is not known which, if any, additional social cues influence this transmission. Extending upon previous field studies, we investigated whether gaze cues paired with emotional facial expressions (neutral, happy, suspicious and fearsome) of an oncoming walking confederate modulate gaze-following by pedestrians moving in a natural corridor. We found that pedestrians walking alone were not sensitive to this manipulation, while individuals traveling together in groups did reliably alter their response in relation to emotional cues. In particular, members of a collective were more likely to follow gaze cues indicative of a potential threat (i.e., suspicious or fearful facial expression). This modulation of visual attention dependent on whether pedestrians are in social aggregates may be important to drive adaptive exploitation of social information, and particularly emotional stimuli within natural contexts. PMID:25052060

  14. Stereo system based on a graphics processing unit for pedestrian detection and tracking

    NASA Astrophysics Data System (ADS)

    Nam, Bodam; Kang, Sungil; Hong, Hyunki; Eem, Changkyoung

    2010-12-01

    This paper presents a novel stereo system, based on a graphics processing unit (GPU), for pedestrian detection in real images. The process of obtaining a dense disparity map and the edge properties of the scene to extract a region of interest (ROI) is designed on a GPU for real-time applications. After extracting the histograms of the oriented gradients on the ROIs, a support vector machine classifies them as pedestrian and nonpedestrian types. The system employs the recognition-by-components method, which compensates for the pose and articulation changes of pedestrians. In order to effectively track spatial pedestrian estimates over sequences, subwindows at distinctive parts of human beings are used as measurements for the Kalman filter.

  15. An Evaluation of a Parent Implemented In Situ Pedestrian Safety Skills Intervention for Individuals with Autism.

    PubMed

    Harriage, Bethany; Blair, Kwang-Sun Cho; Miltenberger, Raymond

    2016-06-01

    This study evaluated an in situ pedestrian safety skills intervention for three individuals with autism , as implemented by their parents. Specifically, this study examined the utility of behavioral skills training (BST) in helping parents implement most-to-least prompting procedures in training their children to use pedestrian safety skills in community settings. A multiple baseline design across participants was used to assess parent implementation of in situ pedestrian safety skills training as well as the correct use of safety skills independently by the participating individuals with autism. Results indicated that parents implemented in situ, most-to-least prompting procedures with high levels of accuracy across street locations during intervention and fading of BST. All child participants significantly improved their pedestrian safety skills during intervention across all natural street settings. For all three participants, the acquired skills were maintained above baseline levels at 1-month follow-up. PMID:26864158

  16. Child Pedestrian Injury: A Review of Behavioral Risks and Preventive Strategies

    PubMed Central

    Schwebel, David C.; Davis, Aaron L.; O’Neal, Elizabeth E.

    2011-01-01

    Pedestrian injury is among the leading causes of pediatric death in the United States and much of the world. This paper is divided into two sections. First, we review the literature on behavioral risk factors for child injury. Cognitive and perceptual development risks are discussed. The roles of distraction, temperament and personality, and social influences from parents and peers are presented. We conclude the first section with brief reviews of environmental risks, pedestrian safety among special populations, and the role of sleep and fatigue on pediatric pedestrian safety. The second section of the review considers child pedestrian injury prevention strategies. Categorized by mode of presentation, we discuss parent instruction strategies, school-based instruction strategies (including crossing guards), and streetside training techniques. Technology-based training strategies using video, internet, and virtual reality are reviewed. We conclude the section on prevention with discussion of community-based interventions. PMID:23066380

  17. 120. E.B. Jeffress Recreation Area. View of stonewalled pedestrian overlook ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    120. E.B. Jeffress Recreation Area. View of stone-walled pedestrian overlook at the cascades, a waterfall on falls creek. Looking southwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  18. Walkyourplace - Evaluating Neighbourhood Accessibility at Street Level

    NASA Astrophysics Data System (ADS)

    Steiniger, S.; Poorazizi, M. E.; Hunter, A. J. S.

    2013-05-01

    The popularity of a neighbourhood is often explained by its perceived "higher" quality of life. Good access to shops, restaurants, parks, etc., is seen as an indicator that reflects improved quality of life. We present a web-based tool for assessment of accessibility to such services. The system evaluates in real time an area that is accessible using pedestrian, transit, and cycling infrastructure. The accessible area is evaluated using "quality of life" indicators, such as the number of grocery stores, shopping and recreation facilities, and local crime within that area. This tool sets itself apart from pre-computed and neighbourhood-level walkability indices, because it makes use of detailed street-level data, rather than block-level generalizations. It uses real network travel time, and, when transit data are provided, permits the creation and evaluation of accessibility areas for a combination of travel modes such as walking with transit use.

  19. Constructal design for pedestrian movement in living spaces: Evacuation configurations

    NASA Astrophysics Data System (ADS)

    Lui, C. H.; Fong, N. K.; Lorente, S.; Bejan, A.; Chow, W. K.

    2012-03-01

    Here we show that the configuration of an inhabited area controls the time required by all the pedestrians to vacate the space. From the minimization of the global evacuation time emerges the optimal configuration of the area. This is a fundamental principle for designing living spaces with efficient evacuation quality, and it is demonstrated here with several simple building blocks that can be used as components of more complex living structures: single walkway, corner, and T-shaped walkway. We show analytically and numerically that the ratio of the widths of the stem and branches of the T-shaped walkway has an optimal value that facilitates the evacuation of all the inhabitants. This result is fundamental, and is the crowd-dynamics equivalent of the Hess-Murray rule for the ratio of diameters in bifurcated ducts with fluid flow.

  20. [Socioecological determinants of the risk of accidents in young pedestrians].

    PubMed

    Joly, M F; Foggin, P; Pless, I

    1991-01-01

    We studied all traffic accidents to pedestrians under age 15 which occurred on the Island of Montreal during an eighteen months period. Data were collected from eleven hospitals and completed with accident police records. A spatial quadrat analysis, a Comparative Accident Index, and a comparative analysis of the means of different socio-ecological variables between high and low risk accident areas revealed interesting patterns. The location of traffic accidents is not random but rather presents a particular spatial structure. High risk zones are characterized by dense population, fast-moving traffic, and the absence of parks. Accidents often take place on two-way streets, far from traffic lights, on dry surfaces, in good weather, and with good visibility. The socio-economic status of the victim's family as measured by education, income, and unemployment, tends to be low. More boys than girls are victims. Children are often injured while getting out of a car or crossing unconventionally. PMID:1754700

  1. Composite material pedestrian bridge for the Port of Bilbao

    NASA Astrophysics Data System (ADS)

    Gorrochategui, I.; Manteca, C.; Yedra, A.; Miguel, R.; del Valle, F. J.

    2012-09-01

    Composite materials in comparison to traditional ones, steel and concrete, present advantages in civil works construction: lower weight, higher corrosion resistance (especially in the marine environment), and ease of installation. On the other hand, fabrication costs are generally higher. This is the reason why this technology is not widely used. This work illustrates the process followed for the design, fabrication and installation of a composite material pedestrian bridge in the Port of Bilbao (Northern Spain). In order to reduce the price of the bridge, the use of low cost materials was considered, therefore polyester resin was selected as the polymeric matrix, and glass fibres as reinforcement. Two material choices were studied. Currently in the market there is high availability of carbon nanoparticles: carbon nanotubes (CNT) and carbon nanofibres (CNF), so it was decided to add this kind of nanoparticles to the reference material with the objective of improving its mechanical properties. The main challenge was to transfer the CNT and CNF excellent properties to the polymeric matrix. This requires dispersing the nanoreinforcements as individual particles in the polymeric matrix to avoid agglomerates. For this reason, an advanced high shear forces dispersion technique (called "three roll mills") was studied and implemented. Also surface functionalization of the nanoreinforcements by chemical treatment was carried out. Herein, a comparison is performed between both materials studied, the explanation of the employment of the reference material (without nanoreinforcement) as the one used in the fabrication of the pedestrian bridge is justified and, finally, the main characteristics of the final design of the structural element are described.

  2. The influence of vehicle front-end design on pedestrian ground impact.

    PubMed

    Crocetta, Gianmarco; Piantini, Simone; Pierini, Marco; Simms, Ciaran

    2015-06-01

    Accident data have shown that in pedestrian accidents with high-fronted vehicles (SUVs and vans) the risk of pedestrian head injuries from the contact with the ground is higher than with low-fronted vehicles (passenger cars). However, the reasons for this remain poorly understood. This paper addresses this question using multibody modelling to investigate the influence of vehicle front height and shape in pedestrian accidents on the mechanism of impact with the ground and on head ground impact speed. To this end, a set of 648 pedestrian/vehicle crash simulations was carried out using the MADYMO multibody simulation software. Impacts were simulated with six vehicle types at three impact speeds (20, 30, 40km/h) and three pedestrian types (50th % male, 5th % female, and 6-year-old child) at six different initial stance configurations, stationary and walking at 1.4m/s. Six different ground impact mechanisms, distinguished from each other by the manner in which the pedestrian impacted the ground, were identified. These configurations have statistically distinct and considerably different distributions of head-ground impact speeds. Pedestrian initial stance configuration (gait and walking speed) introduced a high variability to the head-ground impact speed. Nonetheless, the head-ground impact speed varied significantly between the different ground impact mechanisms identified and the distribution of impact mechanisms was strongly associated with vehicle type. In general, impact mechanisms for adults resulting in a head-first contact with the ground were more severe with high fronted vehicles compared to low fronted vehicles, though there is a speed dependency to these findings. With high fronted vehicles (SUVs and vans) the pedestrian was mainly pushed forward and for children this resulted in high head ground contact speeds. PMID:25813760

  3. Event-Based Modeling of Driver Yielding Behavior to Pedestrians at Two-Lane Roundabout Approaches

    PubMed Central

    Salamati, Katayoun; Schroeder, Bastian J.; Geruschat, Duane R.; Rouphail, Nagui M.

    2013-01-01

    Unlike other types of controlled intersections, drivers do not always comply with the “yield to pedestrian” sign at the roundabouts. This paper aims to identify the contributing factors affecting the likelihood of driver yielding to pedestrians at two-lane roundabouts. It further models the likelihood of driver yielding based on these factors using logistic regression. The models have been applied to 1150 controlled pedestrian crossings at entry and exit legs of two-lane approaches of six roundabouts across the country. The logistic regression models developed support prior research that the likelihood of driver yielding at the entry leg of roundabouts is higher than at the exit. Drivers tend to yield to pedestrians carrying a white cane more often than to sighted pedestrians. Drivers traveling in the far lane, relative to pedestrian location, have a lower probability of yielding to a pedestrian. As the speed increases the probability of driver yielding decreases. At the exit leg of the roundabout, drivers turning right from the adjacent lane have a lower propensity of yielding than drivers coming from other directions. The findings of this paper further suggest that although there has been much debate on pedestrian right-of-way laws and distinction between pedestrian waiting positions (in the street versus at the curb), this factor does not have a significant impact on driver yielding rate. The logistic regression models also quantify the effect of each of these factors on propensity of driver yielding. The models include variables which are specific to each study location and explain the impact size of each study location on probability of yielding. The models generated in this research will be useful to transportation professionals and researchers interested in understanding the factors that impact driver yielding at modern roundabouts. The results of the research can be used to isolate factors that may increase yielding (such as lower roundabout approach

  4. Pedestrian injury analysis with consideration of the selectivity bias in linked police-hospital data.

    PubMed

    Tarko, Andrew; Azam, Md Shafiul

    2011-09-01

    Evaluation of crash-related injuries by medical specialists in hospitals is believed to be more exact than rather a cursory evaluation made at the crash scene. Safety analysts sometimes reach for hospital data and use them in combination with the police crash data. One issue that needs to be addressed is the, so-called, selectivity (or selection) bias possible when data used in analysis are not coming from random sampling. If not properly addressed, this issue can lead to a considerable bias in both the model coefficient estimates and the model predictions. This paper investigates pedestrian injury severity factors using linked police-hospital data. A bivariate ordered probit model with sample selection is used to check for the presence of the selectivity bias and to account for it in the MAIS estimates on the Maximum Abbreviated Injury Scale (MAIS). The presence of the sample selection issue has been confirmed. The selectivity bias is considerable in predictions of low injury levels. The pedestrian injury analysis identified and estimated several severity factors, including pedestrian, road, and vehicle characteristics. Male and older pedestrians were found to be particularly exposed to severe injuries. Rural roads and high-speed urban roads appear to be more dangerous for pedestrians, particularly when crossing such roads. Crossing a road between intersections was found to be particularly dangerous behavior. The size and weight of the vehicle involved in a pedestrian crash were also found to have an effect on the pedestrian injury level. The relevant safety countermeasures that may improve pedestrian safety have been proposed. PMID:21658495

  5. Impact speed and a pedestrian's risk of severe injury or death.

    PubMed

    Tefft, Brian C

    2013-01-01

    This study estimates the risk of severe injury or death for pedestrians struck by vehicles using data from a study of crashes that occurred in the United States in years 1994-1998 and involved a pedestrian struck by a forward-moving car, light truck, van, or sport utility vehicle. The data were weighted to correct for oversampling of pedestrians who were severely injured or killed. Logistic regression was used to adjust for potential confounding related to pedestrian and vehicle characteristics. Risks were standardized to represent the average risk for a pedestrian struck by a car or light truck in the United States in years 2007-2009. Results show that the average risk of a struck pedestrian sustaining an injury of Abbreviated Injury Scale 4 or greater severity reaches 10% at an impact speed of 17.1miles per hour (mph), 25% at 24.9mph, 50% at 33.0mph, 75% at 40.8mph, and 90% at 48.1mph. The average risk of death reaches 10% at an impact speed of 24.1mph, 25% at 32.5mph, 50% at 40.6mph, 75% at 48.0mph, and 90% at 54.6mph. Risks varied by age. For example, the average risk of death for a 70-year-old pedestrian struck at any given speed was similar to the average risk of death for a 30-year-old pedestrian struck at a speed 11.8mph faster. PMID:22935347

  6. Pedestrian at-fault crashes on rural and urban roadways in Alabama.

    PubMed

    Islam, Samantha; Jones, Steven L

    2014-11-01

    The research described in this paper explored the factors contributing to the injury severity resulting from pedestrian at-fault crashes in rural and urban locations in Alabama incorporating the effects of randomness across the observations. Given the occurrence of a crash, random parameter logit models of injury severity (with possible outcomes of major, minor, and possible or no injury) for rural and urban locations were estimated. The estimated models identified statistically significant factors influencing the pedestrian injury severities. The results clearly indicated that there are differences between the influences of a variety of variables on the injury severities resulting from urban versus rural pedestrian at-fault accidents. The results showed that some variables were significant only in one location (urban or rural) but not in the other location. Also, estimation findings showed that several parameters could be modeled as random parameters indicating their varying influences on the injury severity. Based on the results obtained, this paper discusses the effects of different variables on pedestrian injury severities and their possible explanations. From planning and policy perspective, the results of this study justify the need for location specific pedestrian safety research and location specific carefully tailored pedestrian safety campaigns. PMID:25089767

  7. Pedestrian Detection in Far-Infrared Daytime Images Using a Hierarchical Codebook of SURF

    PubMed Central

    Besbes, Bassem; Rogozan, Alexandrina; Rus, Adela-Maria; Bensrhair, Abdelaziz; Broggi, Alberto

    2015-01-01

    One of the main challenges in intelligent vehicles concerns pedestrian detection for driving assistance. Recent experiments have showed that state-of-the-art descriptors provide better performances on the far-infrared (FIR) spectrum than on the visible one, even in daytime conditions, for pedestrian classification. In this paper, we propose a pedestrian detector with on-board FIR camera. Our main contribution is the exploitation of the specific characteristics of FIR images to design a fast, scale-invariant and robust pedestrian detector. Our system consists of three modules, each based on speeded-up robust feature (SURF) matching. The first module allows generating regions-of-interest (ROI), since in FIR images of the pedestrian shapes may vary in large scales, but heads appear usually as light regions. ROI are detected with a high recall rate with the hierarchical codebook of SURF features located in head regions. The second module consists of pedestrian full-body classification by using SVM. This module allows one to enhance the precision with low computational cost. In the third module, we combine the mean shift algorithm with inter-frame scale-invariant SURF feature tracking to enhance the robustness of our system. The experimental evaluation shows that our system outperforms, in the FIR domain, the state-of-the-art Haar-like Adaboost-cascade, histogram of oriented gradients (HOG)/linear SVM (linSVM) and MultiFtrpedestrian detectors, trained on the FIR images. PMID:25871724

  8. Pedestrian detection in far-infrared daytime images using a hierarchical codebook of SURF.

    PubMed

    Besbes, Bassem; Rogozan, Alexandrina; Rus, Adela-Maria; Bensrhair, Abdelaziz; Broggi, Alberto

    2015-01-01

    One of the main challenges in intelligent vehicles concerns pedestrian detection for driving assistance. Recent experiments have showed that state-of-the-art descriptors provide better performances on the far-infrared (FIR) spectrum than on the visible one, even in daytime conditions, for pedestrian classification. In this paper, we propose a pedestrian detector with on-board FIR camera. Our main contribution is the exploitation of the specific characteristics of FIR images to design a fast, scale-invariant and robust pedestrian detector. Our system consists of three modules, each based on speeded-up robust feature (SURF) matching. The first module allows generating regions-of-interest (ROI), since in FIR images of the pedestrian shapes may vary in large scales, but heads appear usually as light regions. ROI are detected with a high recall rate with the hierarchical codebook of SURF features located in head regions. The second module consists of pedestrian full-body classification by using SVM. This module allows one to enhance the precision with low computational cost. In the third module, we combine the mean shift algorithm with inter-frame scale-invariant SURF feature tracking to enhance the robustness of our system. The experimental evaluation shows that our system outperforms, in the FIR domain, the state-of-the-art Haar-like Adaboost-cascade, histogram of oriented gradients (HOG)/linear SVM (linSVM) and MultiFtrpedestrian detectors, trained on the FIR images. PMID:25871724

  9. Potential for the dynamics of pedestrians in a socially interacting group

    NASA Astrophysics Data System (ADS)

    Zanlungo, Francesco; Ikeda, Tetsushi; Kanda, Takayuki

    2014-01-01

    We introduce a simple potential to describe the dynamics of the relative motion of two pedestrians socially interacting in a walking group. We show that the proposed potential, based on basic empirical observations and theoretical considerations, can qualitatively describe the statistical properties of pedestrian behavior. In detail, we show that the two-dimensional probability distribution of the relative distance is determined by the proposed potential through a Boltzmann distribution. After calibrating the parameters of the model on the two-pedestrian group data, we apply the model to three-pedestrian groups, showing that it describes qualitatively and quantitatively well their behavior. In particular, the model predicts that three-pedestrian groups walk in a V-shaped formation and provides accurate values for the position of the three pedestrians. Furthermore, the model correctly predicts the average walking velocity of three-person groups based on the velocity of two-person ones. Possible extensions to larger groups, along with alternative explanations of the social dynamics that may be implied by our model, are discussed at the end of the paper.

  10. The fatality and injury risk of light truck impacts with pedestrians in the United States.

    PubMed

    Lefler, Devon E; Gabler, Hampton C

    2004-03-01

    In the United States, passenger vehicles are shifting from a fleet populated primarily by cars to a fleet dominated by light trucks and vans (LTVs). Because light trucks are heavier, stiffer, and geometrically more blunt than passenger cars, they pose a dramatically different type of threat to pedestrians. This paper investigates the effect of striking vehicle type on pedestrian fatalities and injuries. The analysis incorporates three major sources of data, the Fatality Analysis Reporting System (FARS), the General Estimates System (GES), and the Pedestrian Crash Data Study (PCDS). The paper presents and compares pedestrian impact risk factors for sport utility vehicles, pickup trucks, vans, and cars as developed from analyses of US accident statistics. Pedestrians are found to have a two to three times greater likelihood of dying when struck by an LTV than when struck by a car. Examination of pedestrian injury distributions reveals that, given an impact speed, the probability of serious head and thoracic injury is substantially greater when the striking vehicle is an LTV rather than a car. PMID:14642884

  11. Effect of Aspiration and Mean Gain on the Emergence of Cooperation in Unidirectional Pedestrian Flow

    NASA Astrophysics Data System (ADS)

    Wang, Zi-Yang; Ma, Jian; Zhao, Hui; Qin, Yong; Zhu, Wei; Jia, Li-Min

    2013-03-01

    When more than one pedestrian want to move to the same site, conflicts appear and thus the involved pedestrians play a motion game. In order to describe the emergence of cooperation during the conflict resolving process, an evolutionary cellular automation model is established considering the effect of aspiration and mean gain. In each game, pedestrian may be gentle cooperator or aggressive defector. We propose a set of win-stay-lose-shrift (WSLS) like rules for updating pedestrian's strategy. These rules prescribe that if the mean gain of current strategy between some given steps is larger than aspiration the strategy keeps, otherwise the strategy changes. The simulation results show that a high level aspiration will lead to more cooperation. With the increment of the statistic length, pedestrians will be more rational in decision making. It is also found that when the aspiration level is small enough and the statistic length is large enough all the pedestrian will turn to defectors. We use the prisoner's dilemma model to explain it. At last we discuss the effect of aspiration on fundamental diagram.

  12. The influence of carrying a backpack on college student pedestrian safety.

    PubMed

    Schwebel, David C; Pitts, Danielle Dulion; Stavrinos, Despina

    2009-03-01

    University students walk frequently, and individuals ages 18-22 have among the highest rates of pedestrian injury among any age group in the United States. These injuries are caused by a wide range of individual, interpersonal, and environmental factors, but one factor that has not been previously considered carefully is the influence of wearing a heavy backpack on pedestrian safety. Backpacks are known to slow walking speed and disrupt perception of one's environment, so it is reasonable to question whether they might also influence safe pedestrian behavior. Ninety-six college students engaged in 20 street-crossings within a virtual pedestrian environment. Half the crossings were completed while bearing a backpack weighing 12% of their body weight; the other half were completed without any burdens. Results suggest that participants walked more slowly, left less safe time to spare after crossing the virtual street, and experienced more frequent hits or close calls with traffic when crossing while carrying the backpack. They also missed fewer safe opportunities to cross while carrying the backpack. Our tests of several demographic characteristics, pedestrian behaviors, and backpack use, as covariates suggest the finding holds across all subsamples included in our study. Implications for pedestrian safety and future research are discussed. PMID:19245896

  13. Educational interventions successfully reduce pedestrians' overestimates of their own nighttime visibility.

    PubMed

    Tyrrell, Richard A; Patton, Chad W; Brooks, Johnell O

    2004-01-01

    Pedestrians dramatically overestimate their own visibility at night. This is likely to result in pedestrians unknowingly engaging in dangerous behavior. To determine the extent to which pedestrians' estimates of their own visibility are influenced by educational interventions, clothing reflectance, and headlamp beam setting, participants in 2 experiments estimated their own nighttime visibility by walking toward a stationary car to the point where they believed they were just recognizable as a pedestrian. In the first experiment 48 university students were tested and in the second experiment 9 high-school driver education students were tested. Overall, participants failed to appreciate the benefits of reflective clothing and of high-beam illumination. However, the participants in Experiment 1 who had heard a relevant lecture several weeks earlier gave estimates that were 10% shorter than did a control group. Participants in Experiment 2 heard a more focused and graphic-intensive lecture and gave estimates that were 56% shorter than did a control group. Potential applications of this research include increasing pedestrian safety by designing and implementing research-based public education campaigns aimed at reducing pedestrians' overestimates of their own nighttime visibility. PMID:15151163

  14. Simultaneous Detection and Tracking of Pedestrian from Panoramic Laser Scanning Data

    NASA Astrophysics Data System (ADS)

    Xiao, Wen; Vallet, Bruno; Schindler, Konrad; Paparoditis, Nicolas

    2016-06-01

    Pedestrian traffic flow estimation is essential for public place design and construction planning. Traditional data collection by human investigation is tedious, inefficient and expensive. Panoramic laser scanners, e.g. Velodyne HDL-64E, which scan surroundings repetitively at a high frequency, have been increasingly used for 3D object tracking. In this paper, a simultaneous detection and tracking (SDAT) method is proposed for precise and automatic pedestrian trajectory recovery. First, the dynamic environment is detected using two different methods, Nearest-point and Max-distance. Then, all the points on moving objects are transferred into a space-time (x, y, t) coordinate system. The pedestrian detection and tracking amounts to assign the points belonging to pedestrians into continuous trajectories in space-time. We formulate the point assignment task as an energy function which incorporates the point evidence, trajectory number, pedestrian shape and motion. A low energy trajectory will well explain the point observations, and have plausible trajectory trend and length. The method inherently filters out points from other moving objects and false detections. The energy function is solved by a two-step optimization process: tracklet detection in a short temporal window; and global tracklet association through the whole time span. Results demonstrate that the proposed method can automatically recover the pedestrians trajectories with accurate positions and low false detections and mismatches.

  15. Research of the relationship of pedestrian injury to collision speed, car-type, impact location and pedestrian sizes using human FE model (THUMS Version 4).

    PubMed

    Watanabe, Ryosuke; Katsuhara, Tadasuke; Miyazaki, Hiroshi; Kitagawa, Yuichi; Yasuki, Tsuyoshi

    2012-10-01

    Injuries in car to pedestrian collisions are affected by various factors such as the vehicle body type, pedestrian body size and impact location as well as the collision speed. This study aimed to investigate the influence of such factors taking a Finite Element (FE) approach. A total of 72 collision cases were simulated using three different vehicle FE models (Sedan, SUV, Mini-Van), three different pedestrian FE models (AM50, AF05, AM95), assuming two different impact locations (center and the corner of the bumper) and at four different collision speeds (20, 30, 40 and 50 km/h). The impact kinematics and the responses of the pedestrian model were validated against those in the literature prior to the simulations. The relationship between the collision speed and the predicted occurrence of head and chest injuries was examined for each case, analyzing the impact kinematics of the pedestrian against the vehicle body and resultant loading to the head and the chest. Strain based indicators were used in the simulation model to estimate skeletal injury (bony fracture) and soft tissue (brain and internal organs) injury. The study results primarily showed that the injury risk became higher with the collision speed, but was also affected by the combination of the factors such as the pedestrian size and the impact location. The study also discussed the injury patterns and trends with respect to the factors examined. In all of the simulated conditions, the model did not predict any severe injury at a collision speed of 20 km/h. PMID:23625564

  16. Complementary methods to plan pedestrian evacuation of the French Riviera's beaches in case of tsunami threat: graph- and multi-agent-based modelling

    NASA Astrophysics Data System (ADS)

    Sahal, A.; Leone, F.; Péroche, M.

    2013-07-01

    Small amplitude tsunamis have impacted the French Mediterranean shore (French Riviera) in the past centuries. Some caused casualties; others only generated economic losses. While the North Atlantic and Mediterranean tsunami warning system is being tested and is almost operational, no awareness and preparedness measure is being implemented at a local scale. Evacuation is to be considered along the French Riviera, but no plan exists within communities. We show that various approaches can provide local stakeholders with evacuation capacities assessments to develop adapted evacuation plans through the case study of the Cannes-Antibes region. The complementarity between large- and small-scale approaches is demonstrated with the use of macro-simulators (graph-based) and micro-simulators (multi-agent-based) to select shelter points and choose evacuation routes for pedestrians located on the beach. The first one allows automatically selecting shelter points and measuring and mapping their accessibility. The second one shows potential congestion issues during pedestrian evacuations, and provides leads for the improvement of urban environment. Temporal accessibility to shelters is compared to potential local and distal tsunami travel times, showing a 40 min deficit for an adequate crisis management in the first scenario, and a 30 min surplus for the second one.

  17. Effects of safety measures on driver's speed behavior at pedestrian crossings.

    PubMed

    Bella, Francesco; Silvestri, Manuel

    2015-10-01

    This paper reports the results of a multi-factorial experiment that was aimed at the following: (a) analyzing driver's speed behavior while approaching zebra crossings under different conditions of vehicle-pedestrian interaction and with respect to several safety measures and (b) comparing safety measures and identifying the most effective treatment for zebra crossings. Three safety countermeasures at pedestrian crossings (curb extensions, parking restrictions and advanced yield markings) and the condition of no treatment (baseline condition) were designed on a two-lane urban road and implemented in an advanced driving simulator. Several conditions of vehicle-pedestrian interaction (in terms of the time left for the vehicle to get to the zebra crossing at the moment the pedestrian starts the crossing) were also simulated. Forty-two drivers completed the driving in the simulator. Based on the recorded speed data, two analyses were performed. The first analysis, which focused on the mean speed profiles, revealed that the driver's speed behavior was affected by conditions of vehicle-pedestrian interaction and was fully consistent with previous findings in the literature and with the Threat Avoidance Model developed by Fuller. Further analysis was based on variables that were obtained from the speed profiles of drivers (the speed at the beginning of the deceleration phase, the distance from the zebra crossing where the deceleration began, the minimum speed value reached during the deceleration, the distance from the pedestrian crossing where the braking phase ended and the average deceleration rate). Multivariate variance analysis (MANOVA) revealed that there was a significant main effect for safety measures and for pedestrian conditions (the presence and absence of a pedestrian). The results identified that the curb extension was the countermeasure that induces the most appropriate driver's speed behavior while approaching the zebra crossing. This conclusion was also

  18. The Use of Audible Traffic Signals in the United States.

    ERIC Educational Resources Information Center

    Peck, A. F.; Uslan, M.

    1990-01-01

    This paper discusses audible traffic signals (ATS) and their use by visually impaired pedestrians in the United States and other countries. Areas of concern are noted, including the types of intersections at which ATS should be installed, the locations of poles and buttons for activating the system, and the specific type of device used.…

  19. Analysis of pedestrian accident costs in Sudan using the willingness-to-pay method.

    PubMed

    Mofadal, Adam I A; Kanitpong, Kunnawee; Jiwattanakulpaisarn, Piyapong

    2015-05-01

    The willingness-to-pay (WTP) with contingent valuation (CV) method has been proven to be a valid tool for the valuation of non-market goods or socio-economic costs of road traffic accidents among communities in developed and developing countries. Research on accident costing tends to estimate the value of statistical life (VOSL) for all road users by providing a principle for the evaluation of road safety interventions in cost-benefit analysis. As in many other developing countries, the economic loss of traffic accidents in Sudan is noticeable; however, analytical research to estimate the magnitude and impact of that loss is lacking. Reports have shown that pedestrians account for more than 40% of the total number of fatalities. In this study, the WTP-CV approach was used to determine the amount of money that pedestrians in Sudan are willing to pay to reduce the risk of their own death. The impact of the socioeconomic factors, risk levels, and walking behaviors of pedestrians on their WTP for fatality risk reduction was also evaluated. Data were collected from two cities-Khartoum and Nyala-using a survey questionnaire that included 1400 respondents. The WTP-CV Payment Card Questionnaire was designed to ensure that Sudan pedestrians can easily determine the amount of money that would be required to reduce the fatality risk from a pedestrian-related accident. The analysis results show that the estimated VOSL for Sudanese pedestrians ranges from US$0.019 to US$0.101 million. In addition, the willingness-to-pay by Sudanese pedestrians to reduce their fatality risk tends to increase with age, household income, educational level, safety perception, and average time spent on social activities with family and community. PMID:25794921

  20. A cell-based study on pedestrian acceleration and overtaking in a transfer station corridor

    NASA Astrophysics Data System (ADS)

    Ji, Xiangfeng; Zhou, Xuemei; Ran, Bin

    2013-04-01

    Pedestrian speed in a transfer station corridor is faster than usual and sometimes running can be found among some of them. In this paper, pedestrians are divided into two categories. The first one is aggressive, and the other is conservative. Aggressive pedestrians weaving their way through crowd in the corridor are the study object of this paper. During recent decades, much attention has been paid to the pedestrians' behavior, such as overtaking (also deceleration) and collision avoidance, and that continues in this paper. After sufficiently analyzing the characteristics of pedestrian flow in transfer station corridor, a cell-based model is presented in this paper, including the acceleration (also deceleration) and overtaking analysis. Acceleration (also deceleration) in a corridor is fixed according to Newton's Law and then speed calculated with a kinematic formula is discretized into cells based on the fuzzy logic. After the speed is updated, overtaking is analyzed based on updated speed and force explicitly, compared to rule-based models, which herein we call implicit ones. During the analysis of overtaking, a threshold value to determine the overtaking direction is introduced. Actually, model in this paper is a two-step one. The first step is to update speed, which is the cells the pedestrian can move in one time interval and the other is to analyze the overtaking. Finally, a comparison between the rule-based cellular automata, the model in this paper and data in HCM 2000 is made to demonstrate our model can be used to achieve reasonable simulation of acceleration (also deceleration) and overtaking among pedestrians.

  1. Gestural Viewpoint Signals Referent Accessibility

    ERIC Educational Resources Information Center

    Debreslioska, Sandra; Özyürek, Asli; Gullberg, Marianne; Perniss, Pamela

    2013-01-01

    The tracking of entities in discourse is known to be a bimodal phenomenon. Speakers achieve cohesion in speech by alternating between full lexical forms, pronouns, and zero anaphora as they track referents. They also track referents in co-speech gestures. In this study, we explored how viewpoint is deployed in reference tracking, focusing on…

  2. The Epidemiology and Prevention of Traffic Accidents Involving Child Pedestrians

    PubMed Central

    Read, John H.; Bradley, Eleanor J.; Morison, Joan D.; Lewall, David; Clarke, David A.

    1963-01-01

    A study of 713 motor vehicle accidents involving 749 children in the city of Vancouver is reported. A control group of 110 children who did not have accidents was included in the concurrent study. Factors investigated were the driver, the vehicle, the weather, the time of day, the day of week, the month, the width of roadway, the location of the accident, the child's age, sex, personality, school record, and family background, the type of injury, and the ambulance and hospital service received. Boys were more commonly involved than girls, and most accidents occurred in the 3 to 7 year age group. Head injuries prevailed in the younger age groups and decreased steadily with the age of the child. Specific epidemic areas in the city were identified and selective enforcement was suggested as a possible countermeasure. Hospital records seldom provided a detailed history of the events leading up to the accident. In order to apply the preventive techniques of education and enforcement it was suggested that in each pedestrian traffic accident the driver should be required to accompany the victim to the site of medical care. ImagesFig. 4 PMID:14055829

  3. Influential parameters on particle exposure of pedestrians in urban microenvironments

    NASA Astrophysics Data System (ADS)

    Buonanno, G.; Fuoco, F. C.; Stabile, L.

    2011-03-01

    Exposure to particle concentrations in urban areas was evaluated in several studies since airborne particles are considered to bring about adverse health effects. Transportation modes and urban microenvironments account for the highest contributions to the overall daily particle exposure concentration. In the present study an evaluation of the influential parameters affecting particle exposure of pedestrian in urban areas is reported. Street geometry, traffic mode, wind speed and direction effects were analyzed through an experimental campaign performed in different streets of an Italian town. To this purpose a high-resolution time measurement apparatus was used in order to capture the dynamic of the freshly emitted particles. Number, surface area and mass concentrations and distributions were measured continuously along both the sides of street canyons and avenue canyons during 10-minutes walking routes. The combined effect of street geometry and wind direction may contribute strongly to dilute the fresh particles emitted by vehicles. In particular, street canyons are characterized by lower ventilation phenomena which lead to similar concentration values on both the side of the street. Higher wind speed was found to decrease concentrations in the canyon. Traffic mode also seems to influence exposure concentrations. In particular, submicrometer particle mass concentration was higher as the traffic is more congested; otherwise, coarse fraction dominates mass exposure concentration along street characterized by a more fluent traffic, showing a typical resuspension modality.

  4. Extrinsic Calibration of Camera Networks Based on Pedestrians.

    PubMed

    Guan, Junzhi; Deboeverie, Francis; Slembrouck, Maarten; Van Haerenborgh, Dirk; Van Cauwelaert, Dimitri; Veelaert, Peter; Philips, Wilfried

    2016-01-01

    In this paper, we propose a novel extrinsic calibration method for camera networks by analyzing tracks of pedestrians. First of all, we extract the center lines of walking persons by detecting their heads and feet in the camera images. We propose an easy and accurate method to estimate the 3D positions of the head and feet w.r.t. a local camera coordinate system from these center lines. We also propose a RANSAC-based orthogonal Procrustes approach to compute relative extrinsic parameters connecting the coordinate systems of cameras in a pairwise fashion. Finally, we refine the extrinsic calibration matrices using a method that minimizes the reprojection error. While existing state-of-the-art calibration methods explore epipolar geometry and use image positions directly, the proposed method first computes 3D positions per camera and then fuses the data. This results in simpler computations and a more flexible and accurate calibration method. Another advantage of our method is that it can also handle the case of persons walking along straight lines, which cannot be handled by most of the existing state-of-the-art calibration methods since all head and feet positions are co-planar. This situation often happens in real life. PMID:27171080

  5. Extrinsic Calibration of Camera Networks Based on Pedestrians

    PubMed Central

    Guan, Junzhi; Deboeverie, Francis; Slembrouck, Maarten; Van Haerenborgh, Dirk; Van Cauwelaert, Dimitri; Veelaert, Peter; Philips, Wilfried

    2016-01-01

    In this paper, we propose a novel extrinsic calibration method for camera networks by analyzing tracks of pedestrians. First of all, we extract the center lines of walking persons by detecting their heads and feet in the camera images. We propose an easy and accurate method to estimate the 3D positions of the head and feet w.r.t. a local camera coordinate system from these center lines. We also propose a RANSAC-based orthogonal Procrustes approach to compute relative extrinsic parameters connecting the coordinate systems of cameras in a pairwise fashion. Finally, we refine the extrinsic calibration matrices using a method that minimizes the reprojection error. While existing state-of-the-art calibration methods explore epipolar geometry and use image positions directly, the proposed method first computes 3D positions per camera and then fuses the data. This results in simpler computations and a more flexible and accurate calibration method. Another advantage of our method is that it can also handle the case of persons walking along straight lines, which cannot be handled by most of the existing state-of-the-art calibration methods since all head and feet positions are co-planar. This situation often happens in real life. PMID:27171080

  6. Follow the leader: Visual control of speed in pedestrian following

    PubMed Central

    Rio, Kevin W.; Rhea, Christopher K.; Warren, William H.

    2014-01-01

    When people walk together in groups or crowds they must coordinate their walking speed and direction with their neighbors. This paper investigates how a pedestrian visually controls speed when following a leader on a straight path (one-dimensional following). To model the behavioral dynamics of following, participants in Experiment 1 walked behind a confederate who randomly increased or decreased his walking speed. The data were used to test six models of speed control that used the leader's speed, distance, or combinations of both to regulate the follower's acceleration. To test the optical information used to control speed, participants in Experiment 2 walked behind a virtual moving pole, whose visual angle and binocular disparity were independently manipulated. The results indicate the followers match the speed of the leader, and do so using a visual control law that primarily nulls the leader's optical expansion (change in visual angle), with little influence of change in disparity. This finding has direct applications to understanding the coordination among neighbors in human crowds. PMID:24511143

  7. Determining a Blind Pedestrian's Location and Orientation at Traffic Intersections

    PubMed Central

    Fusco, Giovanni; Shen, Huiying; Murali, Vidya; Coughlan, James M.

    2014-01-01

    This paper describes recent progress on Crosswatch, a smartphone-based computer vision system developed by the authors for providing guidance to blind and visually impaired pedestrians at traffic intersections. One of Crosswatch's key capabilities is determining the user's location (with precision much better than what is obtainable by GPS) and orientation relative to the crosswalk markings in the intersection that he/she is currently standing at; this capability will be used to help him/her find important features in the intersection, such as walk lights, pushbuttons and crosswalks, and achieve proper alignment to these features. We report on two new contributions to Crosswatch: (a) experiments with a modified user interface, tested by blind volunteer participants, that makes it easier to acquire intersection images than with previous versions of Crosswatch; and (b) a demonstration of the system's ability to localize the user with precision better than what is obtainable by GPS, as well as an example of its ability to estimate the user's orientation. PMID:25599097

  8. Discrete element crowd model for pedestrian evacuation through an exit

    NASA Astrophysics Data System (ADS)

    Peng, Lin; Jian, Ma; Siuming, Lo

    2016-03-01

    A series of accidents caused by crowds within the last decades evoked a lot of scientific interest in modeling the movement of pedestrian crowds. Based on the discrete element method, a granular dynamic model, in which the human body is simplified as a self-driven sphere, is proposed to simulate the characteristics of crowd flow through an exit. In this model, the repulsive force among people is considered to have an anisotropic feature, and the physical contact force due to body deformation is quantified by the Hertz contact model. The movement of the human body is simulated by applying the second Newton’s law. The crowd flow through an exit at different desired velocities is studied and simulation results indicated that crowd flow exhibits three distinct states, i.e., smooth state, transition state and phase separation state. In the simulation, the clogging phenomenon occurs more easily when the desired velocity is high and the exit may as a result be totally blocked at a desired velocity of 1.6 m/s or above, leading to faster-to-frozen effect. Project supported by the National Natural Science Foundation of China (Grant Nos. 71473207, 51178445, and 71103148), the Research Grant Council, Government of Hong Kong, China (Grant No. CityU119011), and the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2682014CX103 and 2682014RC05).

  9. CP violation outside the standard model phenomenology for pedestrians

    SciTech Connect

    Lipkin, H.J. ||

    1993-09-23

    So far the only experimental evidence for CP violation is the 1964 discovery of K{sub L}{yields}2{pi} where the two mass eigenstates produced by neutral meson mixing both decay into the same CP eigenstate. This result is described by two parameters {epsilon} and {epsilon}{prime}. Today {epsilon} {approx} its 1964 value, {epsilon}{prime} data are still inconclusive and there is no new evidence for CP violation. One might expect to observe similar phenomena in other systems and also direct CP violation as charge asymmetries between decays of charge conjugate hadrons H{sup {+-}} {yields} f{sup {+-}}. Why is it so hard to find CP violation? How can B Physics help? Does CP lead beyond the standard model? The author presents a pedestrian symmetry approach which exhibits the difficulties and future possibilities of these two types of CP-violation experiments, neutral meson mixing and direct charge asymmetry: what may work, what doesn`t work and why.

  10. Macroscopic modeling of pedestrian and bicycle crashes: A cross-comparison of estimation methods.

    PubMed

    Amoh-Gyimah, Richard; Saberi, Meead; Sarvi, Majid

    2016-08-01

    The paper presents a cross-comparison of different estimation methods to model pedestrian and bicycle crashes. The study contributes to macro level safety studies by providing further methodological and empirical evidence on the various factors that influence the frequency of pedestrian and bicycle crashes at the planning level. Random parameter negative binomial (RPNB) models are estimated to explore the effects of various planning factors associated with total, serious injury and minor injury crashes while accounting for unobserved heterogeneity. Results of the RPNB models were compared with the results of a non-spatial negative binomial (NB) model and a Poisson-Gamma-CAR model. Key findings are, (1) the RPNB model performed best with the lowest mean absolute deviation, mean squared predicted error and Akaiki information criterion measures and (2) signs of estimated parameters are consistent if these variables are significant in models with the same response variables. We found that vehicle kilometers traveled (VKT), population, percentage of commuters cycling or walking to work, and percentage of households without motor vehicles have a significant and positive correlation with the number of pedestrian and bicycle crashes. Mixed land use is also found to have a positive association with the number of pedestrian and bicycle crashes. Results have planning and policy implications aimed at encouraging the use of sustainable modes of transportation while ensuring the safety of pedestrians and cyclist. PMID:27209153

  11. Simulating large-scale pedestrian movement using CA and event driven model: Methodology and case study

    NASA Astrophysics Data System (ADS)

    Li, Jun; Fu, Siyao; He, Haibo; Jia, Hongfei; Li, Yanzhong; Guo, Yi

    2015-11-01

    Large-scale regional evacuation is an important part of national security emergency response plan. Large commercial shopping area, as the typical service system, its emergency evacuation is one of the hot research topics. A systematic methodology based on Cellular Automata with the Dynamic Floor Field and event driven model has been proposed, and the methodology has been examined within context of a case study involving the evacuation within a commercial shopping mall. Pedestrians walking is based on Cellular Automata and event driven model. In this paper, the event driven model is adopted to simulate the pedestrian movement patterns, the simulation process is divided into normal situation and emergency evacuation. The model is composed of four layers: environment layer, customer layer, clerk layer and trajectory layer. For the simulation of movement route of pedestrians, the model takes into account purchase intention of customers and density of pedestrians. Based on evacuation model of Cellular Automata with Dynamic Floor Field and event driven model, we can reflect behavior characteristics of customers and clerks at the situations of normal and emergency evacuation. The distribution of individual evacuation time as a function of initial positions and the dynamics of the evacuation process is studied. Our results indicate that the evacuation model using the combination of Cellular Automata with Dynamic Floor Field and event driven scheduling can be used to simulate the evacuation of pedestrian flows in indoor areas with complicated surroundings and to investigate the layout of shopping mall.

  12. Continuum modelling of pedestrian flows - Part 2: Sensitivity analysis featuring crowd movement phenomena

    NASA Astrophysics Data System (ADS)

    Duives, Dorine C.; Daamen, Winnie; Hoogendoorn, Serge P.

    2016-04-01

    In recent years numerous pedestrian simulation tools have been developed that can support crowd managers and government officials in their tasks. New technologies to monitor pedestrian flows are in dire need of models that allow for rapid state-estimation. Many contemporary pedestrian simulation tools model the movements of pedestrians at a microscopic level, which does not provide an exact solution. Macroscopic models capture the fundamental characteristics of the traffic state at a more aggregate level, and generally have a closed form solution which is necessary for rapid state estimation for traffic management purposes. This contribution presents a next step in the calibration and validation of the macroscopic continuum model detailed in Hoogendoorn et al. (2014). The influence of global and local route choice on the development of crowd movement phenomena, such as dissipation, lane-formation and stripe-formation, is studied. This study shows that most self-organization phenomena and behavioural trends only develop under very specific conditions, and as such can only be simulated using specific parameter sets. Moreover, all crowd movement phenomena can be reproduced by means of the continuum model using one parameter set. This study concludes that the incorporation of local route choice behaviour and the balancing of the aptitude of pedestrians with respect to their own class and other classes are both essential in the correct prediction of crowd movement dynamics.

  13. Issues and challenges for pedestrian active safety systems based on real world accidents.

    PubMed

    Hamdane, Hédi; Serre, Thierry; Masson, Catherine; Anderson, Robert

    2015-09-01

    The purpose of this study was to analyze real crashes involving pedestrians in order to evaluate the potential effectiveness of autonomous emergency braking systems (AEB) in pedestrian protection. A sample of 100 real accident cases were reconstructed providing a comprehensive set of data describing the interaction between the vehicle, the environment and the pedestrian all along the scenario of the accident. A generic AEB system based on a camera sensor for pedestrian detection was modeled in order to identify the functionality of its different attributes in the timeline of each crash scenario. These attributes were assessed to determine their impact on pedestrian safety. The influence of the detection and the activation of the AEB system were explored by varying the field of view (FOV) of the sensor and the level of deceleration. A FOV of 35° was estimated to be required to detect and react to the majority of crash scenarios. For the reaction of a system (from hazard detection to triggering the brakes), between 0.5 and 1s appears necessary. PMID:26047007

  14. Laser-Based Pedestrian Tracking in Outdoor Environments by Multiple Mobile Robots

    PubMed Central

    Ozaki, Masataka; Kakimuma, Kei; Hashimoto, Masafumi; Takahashi, Kazuhiko

    2012-01-01

    This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN)-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI) method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS) and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures. PMID:23202171

  15. Effect of interactions between vehicles and pedestrians on fuel consumption and emissions

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Sun, Jian-Qiao

    2014-12-01

    This paper presents a study of variations of fuel consumption and emissions of vehicles due to random street crossings of pedestrians. The pedestrian and vehicle movement models as well as the interaction model between the two entities are presented. Extensive numerical simulations of single and multiple cars are carried out to investigate the traffic flow rate, vehicle average speed, fuel consumption, CO, HC and NOx emissions. Generally more noncompliant road-crossings of pedestrians lead to higher level of fuel consumptions and emissions of vehicles, and the traffic situation can be improved by imposing higher vehicle speed limit to some extent. Different traffic characteristics in low and high vehicle density regions are studied. The traffic flow is more influenced by crossing pedestrians in the low vehicle density region, while in the high vehicle density region, the interactions among vehicles dominate. The main contribution of this paper lies in the qualitative analysis of the impact of the interactions between pedestrians and vehicles on the traffic, its energy economy and emissions.

  16. Evaluation of users' satisfaction on pedestrian facilities using pair-wise comparison approach

    NASA Astrophysics Data System (ADS)

    Zainol, R.; Ahmad, F.; Nordin, N. A.; Aripin, A. W. M.

    2014-02-01

    Global climate change issues demand people of the world to change the way they live today. Thus, current cities need to be redeveloped towards less use of carbon in their day to day operations. Pedestrianized environment is one of the approaches used in reducing carbon foot print in cities. Heritage cities are the first to be looked into since they were built in the era in which motorized vehicles were minimal. Therefore, the research explores users' satisfaction on assessment of physical attributes of pedestrianization in Melaka Historical City, a UNESCO World Heritage Site. It aims to examine users' satisfaction on pedestrian facilities provided within the study area using pair wise questionnaire comparison approach. A survey of 200 respondents using random sampling was conducted in six different sites namely Jonker Street, Church Street, Kota Street, Goldsmith Street, Merdeka Street to Taming Sari Tower and Merdeka Street to River Cruise terminal. The survey consists of an assessment tool based on a nine-point scale of users' satisfaction level of pathway properties, zebra pedestrian crossing, street furniture, personal safety, adjacent to traffic flow, aesthetic and amenities. Analytical hierarchical process (AHP) was used to avoid any biasness in analyzing the data collected. Findings show that Merdeka Street to Taming Sari Tower as the street that scores the highest satisfaction level that fulfils all the required needs of a pedestrianized environment. Similar assessment elements can be used to evaluate existing streets in other cities and these criteria should also be used in planning for future cities.

  17. Laser-based pedestrian tracking in outdoor environments by multiple mobile robots.

    PubMed

    Ozaki, Masataka; Kakimuma, Kei; Hashimoto, Masafumi; Takahashi, Kazuhiko

    2012-01-01

    This paper presents an outdoors laser-based pedestrian tracking system using a group of mobile robots located near each other. Each robot detects pedestrians from its own laser scan image using an occupancy-grid-based method, and the robot tracks the detected pedestrians via Kalman filtering and global-nearest-neighbor (GNN)-based data association. The tracking data is broadcast to multiple robots through intercommunication and is combined using the covariance intersection (CI) method. For pedestrian tracking, each robot identifies its own posture using real-time-kinematic GPS (RTK-GPS) and laser scan matching. Using our cooperative tracking method, all the robots share the tracking data with each other; hence, individual robots can always recognize pedestrians that are invisible to any other robot. The simulation and experimental results show that cooperating tracking provides the tracking performance better than conventional individual tracking does. Our tracking system functions in a decentralized manner without any central server, and therefore, this provides a degree of scalability and robustness that cannot be achieved by conventional centralized architectures. PMID:23202171

  18. Error Analysis in a Stereo Vision-Based Pedestrian Detection Sensor for Collision Avoidance Applications

    PubMed Central

    Llorca, David F.; Sotelo, Miguel A.; Parra, Ignacio; Ocaña, Manuel; Bergasa, Luis M.

    2010-01-01

    This paper presents an analytical study of the depth estimation error of a stereo vision-based pedestrian detection sensor for automotive applications such as pedestrian collision avoidance and/or mitigation. The sensor comprises two synchronized and calibrated low-cost cameras. Pedestrians are detected by combining a 3D clustering method with Support Vector Machine-based (SVM) classification. The influence of the sensor parameters in the stereo quantization errors is analyzed in detail providing a point of reference for choosing the sensor setup according to the application requirements. The sensor is then validated in real experiments. Collision avoidance maneuvers by steering are carried out by manual driving. A real time kinematic differential global positioning system (RTK-DGPS) is used to provide ground truth data corresponding to both the pedestrian and the host vehicle locations. The performed field test provided encouraging results and proved the validity of the proposed sensor for being used in the automotive sector towards applications such as autonomous pedestrian collision avoidance. PMID:22319323

  19. Stereo vision-based pedestrian detection using multiple features for automotive application

    NASA Astrophysics Data System (ADS)

    Lee, Chung-Hee; Kim, Dongyoung

    2015-12-01

    In this paper, we propose a stereo vision-based pedestrian detection using multiple features for automotive application. The disparity map from stereo vision system and multiple features are utilized to enhance the pedestrian detection performance. Because the disparity map offers us 3D information, which enable to detect obstacles easily and reduce the overall detection time by removing unnecessary backgrounds. The road feature is extracted from the v-disparity map calculated by the disparity map. The road feature is a decision criterion to determine the presence or absence of obstacles on the road. The obstacle detection is performed by comparing the road feature with all columns in the disparity. The result of obstacle detection is segmented by the bird's-eye-view mapping to separate the obstacle area which has multiple objects into single obstacle area. The histogram-based clustering is performed in the bird's-eye-view map. Each segmented result is verified by the classifier with the training model. To enhance the pedestrian recognition performance, multiple features such as HOG, CSS, symmetry features are utilized. In particular, the symmetry feature is proper to represent the pedestrian standing or walking. The block-based symmetry feature is utilized to minimize the type of image and the best feature among the three symmetry features of H-S-V image is selected as the symmetry feature in each pixel. ETH database is utilized to verify our pedestrian detection algorithm.

  20. Pedestrian flow dynamics in a lattice gas model coupled with an evolutionary game.

    PubMed

    Hao, Qing-Yi; Jiang, Rui; Hu, Mao-Bin; Jia, Bin; Wu, Qing-Song

    2011-09-01

    This paper studies unidirectional pedestrian flow by using a lattice gas model with parallel update rules. Game theory is introduced to deal with conflicts that two or three pedestrians want to move into the same site. Pedestrians are either cooperators or defectors. The cooperators are gentle and the defectors are aggressive. Moreover, pedestrians could change their strategy. The fundamental diagram and the cooperator fraction at different system width W have been investigated in detail. It is found that a two-lane system exhibits a first-order phase transition while a multilane system does not. A microscopic mechanism behind the transition has been provided. Mean-field analysis is carried out to calculate the critical density of the transition as well as the probability of games at large value of W. The spatial distribution of pedestrians is investigated, which is found to be dependent (independent) on the initial cooperator fraction when W is small (large). Finally, the influence of the evolutionary game rule has been discussed. PMID:22060456

  1. Pedestrian and Pedalcyclist Injury Costs in the United States by Age and Injury Severity

    PubMed Central

    Miller, Ted R.; Zaloshnja, Eduard; Lawrence, Bruce A.; Crandall, Jeff; Ivarsson, Johan; Finkelstein, A. Eric

    2004-01-01

    This paper estimates the incidence, unit costs, and annual costs of pedestrian and pedalcycle crash injuries in the United States. It includes medical care costs, household and wage work losses, and the value of pain, suffering, and lost quality of life. The estimates are broken down by body region and severity. They rely heavily on data from the health care system. Costs of pedestrian and pedalcycle injuries in 2000 will total $40 billion over the lifetimes of the injured. Most pedalcyclist injury costs and half of pedestrian injury costs do not involve motor vehicles. Youth ages 5–14 face greater annual risks when walking or driving their own pedaled vehicles than when being driven. Children under age 5 experience higher costs than their elders when injured as pedestrians. Our results suggest European and Japanese component tests used to design pedestrian injury countermeasures for motor vehicles are too narrow. Separate lower limb testing is needed for younger children. Testing for torso/vertebral column injury of adults also seems desirable. PMID:15319130

  2. Visibility aids for pedestrians and cyclists: a systematic review of randomised controlled trials.

    PubMed

    Kwan, Irene; Mapstone, James

    2004-05-01

    This study aims to quantify the effect of visibility aids on the occurrence of pedestrian and cyclist-motor vehicle collisions and injuries, and drivers' responses in detection and recognition. Trial reports were systematically reviewed according to predefined eligibility criteria, including randomised controlled trials or controlled before-and-after trials comparing visibility aids and no visibility aids, and of different visibility aids on pedestrian and cyclist safety, and drivers' responses in detection and recognition. This included trials in which the order of interventions was randomised, or balanced using a Latin square design. Two reviewers independently assessed validity of trials and abstracted data. The main outcome measures were pedestrian and cyclist-motor vehicle collisions and injuries, and drivers'/observers' responses in the detection and recognition time, distance and frequency. No trials which assessed the effect of visibility aids on pedestrian and cyclist-motor vehicle collisions and injuries were identified. Twelve trials examined the effectiveness of daytime visibility aids and 25 trials on night time visibility aids, including 882 participants. Drivers' and observers' detection and recognition improved with visibility aids. For daytime, fluorescent materials in yellow, red and orange colours enhanced detection and recognition. "Biomotion" markings enhanced recognition. Substantial heterogeneity between the trials limits the possibility for meta-analysis. Visibility aids have the potential to improve detection and recognition and would merit further development to gain public acceptance. However, the impact of visibility aids on pedestrian and cyclist safety is unknown and needs to be determined. PMID:15003574

  3. Error analysis in a stereo vision-based pedestrian detection sensor for collision avoidance applications.

    PubMed

    Llorca, David F; Sotelo, Miguel A; Parra, Ignacio; Ocaña, Manuel; Bergasa, Luis M

    2010-01-01

    This paper presents an analytical study of the depth estimation error of a stereo vision-based pedestrian detection sensor for automotive applications such as pedestrian collision avoidance and/or mitigation. The sensor comprises two synchronized and calibrated low-cost cameras. Pedestrians are detected by combining a 3D clustering method with Support Vector Machine-based (SVM) classification. The influence of the sensor parameters in the stereo quantization errors is analyzed in detail providing a point of reference for choosing the sensor setup according to the application requirements. The sensor is then validated in real experiments. Collision avoidance maneuvers by steering are carried out by manual driving. A real time kinematic differential global positioning system (RTK-DGPS) is used to provide ground truth data corresponding to both the pedestrian and the host vehicle locations. The performed field test provided encouraging results and proved the validity of the proposed sensor for being used in the automotive sector towards applications such as autonomous pedestrian collision avoidance. PMID:22319323

  4. Far-infrared pedestrian detection for advanced driver assistance systems using scene context

    NASA Astrophysics Data System (ADS)

    Wang, Guohua; Liu, Qiong; Wu, Qingyao

    2016-04-01

    Pedestrian detection is one of the most critical but challenging components in advanced driver assistance systems. Far-infrared (FIR) images are well-suited for pedestrian detection even in a dark environment. However, most current detection approaches just focus on pedestrian patterns themselves, where robust and real-time detection cannot be well achieved. We propose a fast FIR pedestrian detection approach, called MAP-HOGLBP-T, to explicitly exploit the scene context for the driver assistance system. In MAP-HOGLBP-T, three algorithms are developed to exploit the scene contextual information from roads, vehicles, and background objects of high homogeneity, and we employ the Bayesian approach to build a classifier learner which respects the scene contextual information. We also develop a multiframe approval scheme to enhance the detection performance based on spatiotemporal continuity of pedestrians. Our empirical study on real-world datasets has demonstrated the efficiency and effectiveness of the proposed method. The performance is shown to be better than that of state-of-the-art low-level feature-based approaches.

  5. Parents as Advocates for Child Pedestrian Injury Prevention: What Do They Believe about the Efficacy of Prevention Strategies and about How to Create Change?

    ERIC Educational Resources Information Center

    DeFrancesco, Susan; Gielen, Andrea Carlson; Bishai, David; Mahoney, Patricia; Ho, Shiu; Guyer, Bernard

    2003-01-01

    This study describes the support of parents and other community members for child pedestrian safety measures, their willingness to pay in terms of volunteer time and money for efforts to make child pedestrian safety improvements in their neighborhood, and their views on how to affect child pedestrian safety improvements in their communities. In…

  6. Federal Highway Administration University Course on Bicycle and Pedestrian Transportation. Publication No. FHWA-HRT-05-133

    ERIC Educational Resources Information Center

    Turner, Shawn; Sandt, Laura; Toole, Jennifer; Benz, Robert; Patten, Robert

    2006-01-01

    This "Student Workbook" contains 24 lessons of resource material that is intended for use in university courses on bicycle and pedestrian transportation. The lessons span a wide range of topics including an introduction to bicycling and walking issues, planning and designing for bicycle and pedestrian facilities, and supporting elements and…

  7. Reducing Conflicts between Motor Vehicles and Pedestrians: The Separate and Combined Effects of Pavement Markings and a Sign Prompt

    ERIC Educational Resources Information Center

    Huybers, Sherry; Van Houten, Ron; Malenfant, J.E. Louis

    2004-01-01

    The effects of a symbolic "yield here to pedestrians" sign and advance yield pavement markings on pedestrian/motor vehicle conflicts, motorists' yielding behavior, and the distance motorists' yield in advance of crosswalks were evaluated at multilane crosswalks at uncontrolled T intersections. In Experiment 1, the sign, when used alone, reduced…

  8. An M/M/c/K State-Dependent Model for Pedestrian Flow Control and Design of Facilities.

    PubMed

    Rahman, Khalidur; Abdul Ghani, Noraida; Kamil, Anton Abdulbasah; Mustafa, Adli; Chowdhury, Md Ahmed Kabir

    2015-01-01

    Pedestrian overflow causes queuing delay and in turn, is controlled by the capacity of a facility. Flow control or blocking control takes action to avoid queues from building up to extreme values. Thus, in this paper, the problem of pedestrian flow control in open outdoor walking facilities in equilibrium condition is investigated using M/M/c/K queuing models. State dependent service rate based on speed and density relationship is utilized. The effective rate of the Poisson arrival process to the facility is determined so as there is no overflow of pedestrians. In addition, the use of the state dependent queuing models to the design of the facilities and the effect of pedestrian personal capacity on the design and the traffic congestion are discussed. The study does not validate the sustainability of adaptation of Western design codes for the pedestrian facilities in the countries like Bangladesh. PMID:26196124

  9. An M/M/c/K State-Dependent Model for Pedestrian Flow Control and Design of Facilities

    PubMed Central

    Rahman, Khalidur; Abdul Ghani, Noraida; Kamil, Anton Abdulbasah; Mustafa, Adli; Chowdhury, Md. Ahmed Kabir

    2015-01-01

    Pedestrian overflow causes queuing delay and in turn, is controlled by the capacity of a facility. Flow control or blocking control takes action to avoid queues from building up to extreme values. Thus, in this paper, the problem of pedestrian flow control in open outdoor walking facilities in equilibrium condition is investigated using M/M/c/K queuing models. State dependent service rate based on speed and density relationship is utilized. The effective rate of the Poisson arrival process to the facility is determined so as there is no overflow of pedestrians. In addition, the use of the state dependent queuing models to the design of the facilities and the effect of pedestrian personal capacity on the design and the traffic congestion are discussed. The study does not validate the sustainability of adaptation of Western design codes for the pedestrian facilities in the countries like Bangladesh. PMID:26196124

  10. Deep mRNA Sequencing of the Tritonia diomedea Brain Transcriptome Provides Access to Gene Homologues for Neuronal Excitability, Synaptic Transmission and Peptidergic Signalling

    PubMed Central

    Senatore, Adriano; Edirisinghe, Neranjan; Katz, Paul S.

    2015-01-01

    Background The sea slug Tritonia diomedea (Mollusca, Gastropoda, Nudibranchia), has a simple and highly accessible nervous system, making it useful for studying neuronal and synaptic mechanisms underlying behavior. Although many important contributions have been made using Tritonia, until now, a lack of genetic information has impeded exploration at the molecular level. Results We performed Illumina sequencing of central nervous system mRNAs from Tritonia, generating 133.1 million 100 base pair, paired-end reads. De novo reconstruction of the RNA-Seq data yielded a total of 185,546 contigs, which partitioned into 123,154 non-redundant gene clusters (unigenes). BLAST comparison with RefSeq and Swiss-Prot protein databases, as well as mRNA data from other invertebrates (gastropod molluscs: Aplysia californica, Lymnaea stagnalis and Biomphalaria glabrata; cnidarian: Nematostella vectensis) revealed that up to 76,292 unigenes in the Tritonia transcriptome have putative homologues in other databases, 18,246 of which are below a more stringent E-value cut-off of 1x10-6. In silico prediction of secreted proteins from the Tritonia transcriptome shotgun assembly (TSA) produced a database of 579 unique sequences of secreted proteins, which also exhibited markedly higher expression levels compared to other genes in the TSA. Conclusions Our efforts greatly expand the availability of gene sequences available for Tritonia diomedea. We were able to extract full length protein sequences for most queried genes, including those involved in electrical excitability, synaptic vesicle release and neurotransmission, thus confirming that the transcriptome will serve as a useful tool for probing the molecular correlates of behavior in this species. We also generated a neurosecretome database that will serve as a useful tool for probing peptidergic signalling systems in the Tritonia brain. PMID:25719197

  11. A Hybrid Indoor Localization and Navigation System with Map Matching for Pedestrians Using Smartphones

    PubMed Central

    Tian, Qinglin; Salcic, Zoran; Wang, Kevin I-Kai; Pan, Yun

    2015-01-01

    Pedestrian dead reckoning is a common technique applied in indoor inertial navigation systems that is able to provide accurate tracking performance within short distances. Sensor drift is the main bottleneck in extending the system to long-distance and long-term tracking. In this paper, a hybrid system integrating traditional pedestrian dead reckoning based on the use of inertial measurement units, short-range radio frequency systems and particle filter map matching is proposed. The system is a drift-free pedestrian navigation system where position error and sensor drift is regularly corrected and is able to provide long-term accurate and reliable tracking. Moreover, the whole system is implemented on a commercial off-the-shelf smartphone and achieves real-time positioning and tracking performance with satisfactory accuracy. PMID:26690170

  12. Lane formation in pedestrian counterflows driven by a potential field considering following and avoidance behaviours

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Wang, Xiaolu; Zheng, Xiaoping

    2015-08-01

    Lane formation in pedestrian counterflows is an interesting self-organization phenomenon. It is believed to be caused by the following or avoidance behaviours of pedestrians. In this paper, a potential field CA model that considers the velocity and density distributions of a crowd and their subjective consciousness is proposed to study the effects of the two behaviours on lane formation in the case of a pedestrian counterflow in a corridor with a periodic boundary. An indexing system is introduced to distinguish the three different patterns observed in the counterflow, and a smoothness index is introduced to measure the smoothness of the counterflow. It is found that avoidance behaviour is more relevant to lane formation than following behaviour. Some differences between the two behaviours are also presented.

  13. Self-organized phenomena of pedestrian counter flow in a channel under periodic boundary conditions

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Duan, Xiao-Yin; Dong, Li-Yun

    2012-10-01

    In this paper we investigate self-organized phenomena such as lane formation generated by pedestrian counter flow in a channel. The lattice gas model is extended to take the effect of walkers in the opposite direction into account simultaneously when they are in the view field of a walker, i.e., walkers tend to follow the leaders in the same direction and avoid conflicts with those walking towards them. The improved model is then used to mimic pedestrian counter flow in a channel under periodic boundary conditions. Numerical simulations show that lane formation is well reproduced, and this process is rather rapid which coincides with real pedestrian traffic. The average velocity and critical density are found to increase to some degree with the consideration of view field.

  14. A Hybrid Indoor Localization and Navigation System with Map Matching for Pedestrians Using Smartphones.

    PubMed

    Tian, Qinglin; Salcic, Zoran; Wang, Kevin I-Kai; Pan, Yun

    2015-01-01

    Pedestrian dead reckoning is a common technique applied in indoor inertial navigation systems that is able to provide accurate tracking performance within short distances. Sensor drift is the main bottleneck in extending the system to long-distance and long-term tracking. In this paper, a hybrid system integrating traditional pedestrian dead reckoning based on the use of inertial measurement units, short-range radio frequency systems and particle filter map matching is proposed. The system is a drift-free pedestrian navigation system where position error and sensor drift is regularly corrected and is able to provide long-term accurate and reliable tracking. Moreover, the whole system is implemented on a commercial off-the-shelf smartphone and achieves real-time positioning and tracking performance with satisfactory accuracy. PMID:26690170

  15. Calibrating floor field cellular automaton models for pedestrian dynamics by using likelihood function optimization

    NASA Astrophysics Data System (ADS)

    Lovreglio, Ruggiero; Ronchi, Enrico; Nilsson, Daniel

    2015-11-01

    The formulation of pedestrian floor field cellular automaton models is generally based on hypothetical assumptions to represent reality. This paper proposes a novel methodology to calibrate these models using experimental trajectories. The methodology is based on likelihood function optimization and allows verifying whether the parameters defining a model statistically affect pedestrian navigation. Moreover, it allows comparing different model specifications or the parameters of the same model estimated using different data collection techniques, e.g. virtual reality experiment, real data, etc. The methodology is here implemented using navigation data collected in a Virtual Reality tunnel evacuation experiment including 96 participants. A trajectory dataset in the proximity of an emergency exit is used to test and compare different metrics, i.e. Euclidean and modified Euclidean distance, for the static floor field. In the present case study, modified Euclidean metrics provide better fitting with the data. A new formulation using random parameters for pedestrian cellular automaton models is also defined and tested.

  16. Teaching pedestrian skills to retarded persons: generalization from the classroom to the natural environment.

    PubMed Central

    Page, T J; Iwata, B A; Neef, N A

    1976-01-01

    Little attention has been given to teaching adaptive community skills to retarded persons. In this study, five retarded male students were taught basic pedestrian skills in a classroom- Training was conducted on a model built to simulate city traffic conditions. Each subject was taught five specific skills involved in street crossing in sequence, viz. intersection recognition, pedestrian-light skills, traffic-light skills, and skills for two different stop-sign conditions. Before, during, and after training, subjects were tested on generalization probes on model and under actual city traffic conditions. Results of a multiple-baseline design acorss both subjects and behaviors indicated that after receiving classroom training on the skills, each subject exhibited appropriate pedestrian skills under city traffic conditions. In addition, training in some skills appeared to facilitate performance in skills not yet trained. PMID:1002631

  17. Improving Inertial Pedestrian Dead-Reckoning by Detecting Unmodified Switched-on Lamps in Buildings

    PubMed Central

    Jiménez, Antonio R.; Zampella, Francisco; Seco, Fernando

    2014-01-01

    This paper explores how inertial Pedestrian Dead-Reckoning (PDR) location systems can be improved with the use of a light sensor to measure the illumination gradients created when a person walks under ceiling-mounted unmodified indoor lights. The process of updating the inertial PDR estimates with the information provided by light detections is a new concept that we have named Light-matching (LM). The displacement and orientation change of a person obtained by inertial PDR is used by the LM method to accurately propagate the location hypothesis, and vice versa; the LM approach benefits the PDR approach by obtaining an absolute localization and reducing the PDR-alone drift. Even from an initially unknown location and orientation, whenever the person passes below a switched-on light spot, the location likelihood is iteratively updated until it potentially converges to a unimodal probability density function. The time to converge to a unimodal position hypothesis depends on the number of lights detected and the asymmetries/irregularities of the spatial distribution of lights. The proposed LM method does not require any intensity illumination calibration, just the pre-storage of the position and size of all lights in a building, irrespective of their current on/off state. This paper presents a detailed description of the light-matching concept, the implementation details of the LM-assisted PDR fusion scheme using a particle filter, and several simulated and experimental tests, using a light sensor-equipped Galaxy S3 smartphone and an external foot-mounted inertial sensor. The evaluation includes the LM-assisted PDR approach as well as the fusion with other signals of opportunity (WiFi, RFID, Magnetometers or Map-matching) in order to compare their contribution in obtaining high accuracy indoor localization. The integrated solution achieves a localization error lower than 1 m in most of the cases. PMID:24394599

  18. Improving inertial Pedestrian Dead-Reckoning by detecting unmodified switched-on lamps in buildings.

    PubMed

    Jiménez, Antonio R; Zampella, Francisco; Seco, Fernando

    2014-01-01

    This paper explores how inertial Pedestrian Dead-Reckoning (PDR) location systems can be improved with the use of a light sensor to measure the illumination gradients created when a person walks under ceiling-mounted unmodified indoor lights. The process of updating the inertial PDR estimates with the information provided by light detections is a new concept that we have named Light-matching (LM). The displacement and orientation change of a person obtained by inertial PDR is used by the LM method to accurately propagate the location hypothesis, and vice versa; the LM approach benefits the PDR approach by obtaining an absolute localization and reducing the PDR-alone drift. Even from an initially unknown location and orientation, whenever the person passes below a switched-on light spot, the location likelihood is iteratively updated until it potentially converges to a unimodal probability density function. The time to converge to a unimodal position hypothesis depends on the number of lights detected and the asymmetries/irregularities of the spatial distribution of lights. The proposed LM method does not require any intensity illumination calibration, just the pre-storage of the position and size of all lights in a building, irrespective of their current on/off state. This paper presents a detailed description of the light-matching concept, the implementation details of the LM-assisted PDR fusion scheme using a particle filter, and several simulated and experimental tests, using a light sensor-equipped Galaxy S3 smartphone and an external foot-mounted inertial sensor. The evaluation includes the LM-assisted PDR approach as well as the fusion with other signals of opportunity (WiFi, RFID, Magnetometers or Map-matching) in order to compare their contribution in obtaining high accuracy indoor localization. The integrated solution achieves a localization error lower than 1 m in most of the cases. PMID:24394599

  19. Pedestrian Injuries By Source: Serious and Disabling Injuries in US and European Cases

    PubMed Central

    Mallory, Ann; Fredriksson, Rikard; Rosén, Erik; Donnelly, Bruce

    2012-01-01

    US and European pedestrian crash cases were analyzed to determine frequency of injury by body region and by the vehicle component identified as the injury source. US pedestrian data was drawn from the Pedestrian Crash Data Study (PCDS). European pedestrian data was drawn from the German In-Depth Accident Study (GIDAS). Results were analyzed in terms of both serious injury (AIS 3+) and disabling injury estimated with the Functional Capacity Index (FCI). The results are presented in parallel for a more complete international perspective on injuries and injury sources. Lower extremity injury from bumper impact and head&face injury from windshield impact were the most frequent combinations for both serious and disabling injuries. Serious lower extremity injuries from bumper contact occurred in 43% of seriously injured pedestrian cases in US PCDS data and 35% of European GIDAS cases. Lower-extremity bumper injuries also account for more than 20% of disability in both datasets. Serious head &face injuries from windshield contact occur in 27% of PCDS and 15% of GIDAS serious injury cases. While bumper impacts primarily result in lower extremity injury and windshield impacts are most often associated with head & face injuries, the hood and hood leading edge are responsible for serious and disabling injuries to a number of different body regions. Therefore, while it is appropriate to focus on lower extremity injury when studying bumper performance and on head injury risk when studying windshield impact, pedestrian performance of other components may require better understanding of injury risk for multiple body regions. PMID:23169112

  20. Effectiveness of a Safe Routes to School Program in Preventing School-Aged Pedestrian Injury

    PubMed Central

    Li, Guohua

    2013-01-01

    Background: In 2005, the US Congress allocated $612 million for a national Safe Routes to School (SRTS) program to encourage walking and bicycling to schools. We analyzed motor vehicle crash data to assess the effectiveness of SRTS interventions in reducing school-aged pedestrian injury in New York City. Methods: Using geocoded motor vehicle crash data for 168 806 pedestrian injuries in New York City between 2001 and 2010, annual pedestrian injury rates per 10 000 population were calculated for different age groups and for census tracts with and without SRTS interventions during school-travel hours (defined as 7 am to 9 am and 2 pm to 4 pm, Monday through Friday during September through June). Results: During the study period, the annual rate of pedestrian injury decreased 33% (95% confidence interval [CI]: 30 to 36) among school-aged children (5- to 19-year-olds) and 14% (95% CI: 12 to 16) in other age groups. The annual rate of school-aged pedestrian injury during school-travel hours decreased 44% (95% CI: 17 to 65) from 8.0 injuries per 10 000 population in the preintervention period (2001–2008) to 4.4 injuries per 10 000 population in the postintervention period (2009–2010) in census tracts with SRTS interventions. The rate remained virtually unchanged in census tracts without SRTS interventions (0% [95% CI: –8 to 8]). Conclusions: Implementation of the SRTS program in New York City has contributed to a marked reduction in pedestrian injury in school-aged children. PMID:23319533

  1. Discrete element method for emergency flow of pedestrian in S-type corridor.

    PubMed

    Song, Gyeongwon; Park, Junyoung

    2014-10-01

    Pedestrian flow in curved corridor should be modeled before design because this type of corridor can be most dangerous part during emergency evacuation. In this study, this flow is analyzed by Discrete Element Method with psychological effects. As the turning slope of corridor increases, the evacuation time is linearly increases. However, in the view of crashed death accident, the case with 90 degree turning slope can be dangerous because there are 3 dangerous points. To solve this matter, the pedestrian gathering together in curved part should be dispersed. PMID:25942811

  2. Pedestrian evacuation in view and hearing limited condition: The impact of communication and memory

    NASA Astrophysics Data System (ADS)

    Xue, Shuqi; Jia, Bin; Jiang, Rui; Shan, Jingjing

    2016-09-01

    This paper studies pedestrian evacuation in view and hearing limited condition based on the social force approach. It is assumed that there are two types of pedestrians: Informed individuals know the exit location whereas uninformed individuals do not. The uninformed individuals can communicate with the informed ones within their perceptual fields, thus learning to know and memorize the exit location. We consider cases with and without communication/memory. The simulations show communication and memory are able to enhance the evacuation efficiency. We also investigate the impact of communication on the efficiency of an emergency exit.

  3. Coarse-grained particle model for pedestrian flow using diffusion maps

    NASA Astrophysics Data System (ADS)

    Marschler, Christian; Starke, Jens; Liu, Ping; Kevrekidis, Ioannis G.

    2014-01-01

    Interacting particle systems constitute the dynamic model of choice in a variety of application areas. A prominent example is pedestrian dynamics, where good design of escape routes for large buildings and public areas can improve evacuation in emergency situations, avoiding exit blocking and the ensuing panic. Here we employ diffusion maps to study the coarse-grained dynamics of two pedestrian crowds trying to pass through a door from opposite sides. These macroscopic variables and the associated smooth embeddings lead to a better description and a clearer understanding of the nature of the transition to oscillatory dynamics. We also compare the results to those obtained through intuitively chosen macroscopic variables.

  4. Hidden Markov Model-based Pedestrian Navigation System using MEMS Inertial Sensors

    NASA Astrophysics Data System (ADS)

    Zhang, Yingjun; Liu, Wen; Yang, Xuefeng; Xing, Shengwei

    2015-02-01

    In this paper, a foot-mounted pedestrian navigation system using MEMS inertial sensors is implemented, where the zero-velocity detection is abstracted into a hidden Markov model with 4 states and 15 observations. Moreover, an observations extraction algorithm has been developed to extract observations from sensor outputs; sample sets are used to train and optimize the model parameters by the Baum-Welch algorithm. Finally, a navigation system is developed, and the performance of the pedestrian navigation system is evaluated using indoor and outdoor field tests, and the results show that position error is less than 3% of total distance travelled.

  5. Pedestrian detection in thermal images: An automated scale based region extraction with curvelet space validation

    NASA Astrophysics Data System (ADS)

    Lakshmi, A.; Faheema, A. G. J.; Deodhare, Dipti

    2016-05-01

    Pedestrian detection is a key problem in night vision processing with a dozen of applications that will positively impact the performance of autonomous systems. Despite significant progress, our study shows that performance of state-of-the-art thermal image pedestrian detectors still has much room for improvement. The purpose of this paper is to overcome the challenge faced by the thermal image pedestrian detectors, which employ intensity based Region Of Interest (ROI) extraction followed by feature based validation. The most striking disadvantage faced by the first module, ROI extraction, is the failed detection of cloth insulted parts. To overcome this setback, this paper employs an algorithm and a principle of region growing pursuit tuned to the scale of the pedestrian. The statistics subtended by the pedestrian drastically vary with the scale and deviation from normality approach facilitates scale detection. Further, the paper offers an adaptive mathematical threshold to resolve the problem of subtracting the background while extracting cloth insulated parts as well. The inherent false positives of the ROI extraction module are limited by the choice of good features in pedestrian validation step. One such feature is curvelet feature, which has found its use extensively in optical images, but has as yet no reported results in thermal images. This has been used to arrive at a pedestrian detector with a reduced false positive rate. This work is the first venture made to scrutinize the utility of curvelet for characterizing pedestrians in thermal images. Attempt has also been made to improve the speed of curvelet transform computation. The classification task is realized through the use of the well known methodology of Support Vector Machines (SVMs). The proposed method is substantiated with qualified evaluation methodologies that permits us to carry out probing and informative comparisons across state-of-the-art features, including deep learning methods, with six

  6. Empirical Behavioral Models to Support Alternative Tools for the Analysis of Mixed-Priority Pedestrian-Vehicle Interaction in a Highway Capacity Context

    PubMed Central

    Rouphail, Nagui M.

    2011-01-01

    This paper presents behavioral-based models for describing pedestrian gap acceptance at unsignalized crosswalks in a mixed-priority environment, where some drivers yield and some pedestrians cross in gaps. Logistic regression models are developed to predict the probability of pedestrian crossings as a function of vehicle dynamics, pedestrian assertiveness, and other factors. In combination with prior work on probabilistic yielding models, the results can be incorporated in a simulation environment, where they can more fully describe the interaction of these two modes. The approach is intended to supplement HCM analytical procedure for locations where significant interaction occurs between drivers and pedestrians, including modern roundabouts. PMID:21643488

  7. An Analysis of Distance from Collision Site to Pedestrian Residence in Pedestrian versus Automobile Collisions Presenting to a Level 1 Trauma Center.

    PubMed

    Anderson, Craig L; Dominguez, Kathlynn M; Hoang, Teresa V; Rowther, Armaan Ahmed; Carroll, M Christy; Lotfipour, Shahram; Hoonpongsimanont, Wirachin; Chakravarthy, Bharath

    2012-01-01

    This study tests the hypothesis that most pedestrian collisions occur near victims' homes. Patients involved in automobile versus pedestrian collisions who presented to the emergency department at a Level I trauma center between January 2000 and December 2009 were included in the study. Patient demographics were obtained from the trauma registry. Home address was determined from hospital records, collision site was determined from the paramedic run sheet, and the shortest walking distance between the collision site and pedestrian residence was determined using Google Maps. We summarized distances for groups with the median and compared groups using the Kruskal-Wallis rank test. We identified 1917 pedestrian injury cases and identified both residence address and collision location for 1213 cases (63%). Forty-eight percent of the collisions were near home (within 1.1 km, 95% CI 45-51%). Median distance from residence to collision site was 1.4 km (interquartile range 0.3-7.4 km). For ages 0-17, the median distance 0.7 km, and 59% (95% CI 54-63%) of collisions occurred near home. For ages 65 and older, the median distance was 0.6 km and 65% (95% CI 55-73%) were injured near home. Distance did not differ by sex, race, ethnicity, or blood alcohol level. More severe injuries (Injury Severity Score ≥ 16) occurred further from home than less severe injuries (median 1.9 km vs. 1.3 km, p=.01). Patients with a hospital stay of 3 days or less were injured closer to home (median 1.3 km) than patients with a hospital stay of 4 days or more (median 1.8 km, p=.001). Twenty-two percent were injured within the same census tract as their home, 22% on the boundary of their home census tract, and 55% in a different census tract. PMID:23169114

  8. A pedestrian dead-reckoning system that considers the heel-strike and toe-off phases when using a foot-mounted IMU

    NASA Astrophysics Data System (ADS)

    Ju, Hojin; Lee, Min Su; Park, So Young; Song, Jin Woo; Park, Chan Gook

    2016-01-01

    In this paper, we propose an advanced pedestrian dead-reckoning (PDR) algorithm that considers the heel-strike and toe-off phases. Generally, PDR systems that use a foot-mounted inertial measurement unit are based on an inertial navigation system with an extended Kalman filter (EKF). To reduce the influence of the bias and white noises in the gyroscope and accelerometer signals, a zero-velocity update is often adopted at the stance phase. However, transient and large acceleration, which cannot be measured by the accelerometer used in pedestrian navigation, occur momentarily in the heel-strike phase. The velocity information from integration of the acceleration is not reliable because the acceleration is not measured in the heel-strike phase. Therefore, the designed EKF does not correctly reflect the actual environment, because conventional algorithms do not take the non-measurable acceleration into consideration. In order to reflect the actual environment, we propose a PDR system that considers the non-measurable acceleration from the heel-strike impact. To improve the PDR system’s performance, the proposed algorithm uses a new velocity measurement obtained using the constraint between the surface and the foot during the toe-off phase. The experimental results show improved filter performance after comparison of the proposed algorithm and a conventional algorithm.

  9. The Impact of a Signalized Crosswalk on Traffic Speed and Street-Crossing Behaviors of Residents in an Underserved Neighborhood.

    PubMed

    Schultz, Courtney L; Sayers, Stephen P; Wilhelm Stanis, Sonja A; Thombs, Lori A; Thomas, Ian M; Canfield, Shannon M

    2015-10-01

    Infrastructure improvements such as pedestrian crosswalks that calm traffic and increase access to physical activity opportunities could alleviate important barriers to active living in underserved communities with outdated built environments. The purpose of this study was to explore how the built environment influences street-crossing behaviors and traffic speeds in a low-income neighborhood with barriers to active living in Columbia, Missouri. In 2013, a signalized pedestrian crosswalk and 400-ft-long median was constructed along a busy 5-lane, high-speed arterial highway linking low-income housing with a park and downtown areas. Data collection occurred prior to June 2012, and after June 2013, completion of the project at the intervention site and control site. Direct observation of street-crossing behaviors was performed at designated intersections/crosswalks or non-designated crossing points. Traffic volume and speed were captured using embedded magnetic traffic detectors. At the intervention site, designated crossings increased at the new crosswalk (p < 0.001), but not at non-designated crossings (p = 0.52) or designated crossings at intersections (p = 0.41). At the control site, there was no change in designated crossings (p = 0.94) or non-designated crossings (p = 0.79). Motor vehicles traveling above the speed limit of 35 mph decreased from 62,056 (46 %) to 46,256 (35 %) (p < 0.001) at the intervention site and increased from 57,891 (49 %) to 65,725 (59 %) (p < 0.001) at the control site. The installation of a signalized crosswalk facilitated an increase in safe street crossings and calmed traffic volume and speed in an underserved neighborhood. We believe these findings have significant public health implications that could be critical to advocacy efforts to improve infrastructure projects in similar communities. PMID:26354602

  10. Full-duplex fiber-wireless link for alternative wired and 40-GHz band wireless access based on differential quaternary phase-shift optical single sideband millimeter-wave signal

    NASA Astrophysics Data System (ADS)

    Zhang, Ruijiao; Ma, Jianxin; Xin, Xiangjun

    2015-02-01

    A full-duplex fiber-wireless link with a uniform single sideband differential quaternary phase-shift keying optical millimeter-wave signal is proposed to provide wired or 40-GHz band wireless access alternatively. The uniform optical millimeter-wave signal that supports services for wired or wireless users is produced via an LiNbO3 Mach-Zehnder modulator. After being transmitted to the hybrid optical network unit (HONU), it can be demodulated in different patterns on the demand of the user terminals for wired or wireless access. Simultaneously, part of the blank optical carrier abstracted from it is reused as the uplink optical carrier, so the HONU is free from the laser source, and thus, the complexity and cost of the system are reduced. Moreover, since the two tones of the dual-tone optical millimeter wave come from the same source, they maintain high coherency even after being transmitted over fiber. Additionally, the downlink data are carried by one tone of the dual-tone optical millimeter wave, so the downlink optical millimeter-wave signal suffers little from the fiber chromatic dispersion and laser phase noise. The theoretical analysis and simulation results show that our proposed full-duplex link for alternative wired and wireless access maintains good performance even when the transmission link with standard single mode fiber is extended to 30 km.

  11. Recognizing pedestrian's unsafe behaviors in far-infrared imagery at night

    NASA Astrophysics Data System (ADS)

    Lee, Eun Ju; Ko, Byoung Chul; Nam, Jae-Yeal

    2016-05-01

    Pedestrian behavior recognition is important work for early accident prevention in advanced driver assistance system (ADAS). In particular, because most pedestrian-vehicle crashes are occurred from late of night to early of dawn, our study focus on recognizing unsafe behavior of pedestrians using thermal image captured from moving vehicle at night. For recognizing unsafe behavior, this study uses convolutional neural network (CNN) which shows high quality of recognition performance. However, because traditional CNN requires the very expensive training time and memory, we design the light CNN consisted of two convolutional layers and two subsampling layers for real-time processing of vehicle applications. In addition, we combine light CNN with boosted random forest (Boosted RF) classifier so that the output of CNN is not fully connected with the classifier but randomly connected with Boosted random forest. We named this CNN as randomly connected CNN (RC-CNN). The proposed method was successfully applied to the pedestrian unsafe behavior (PUB) dataset captured from far-infrared camera at night and its behavior recognition accuracy is confirmed to be higher than that of some algorithms related to CNNs, with a shorter processing time.

  12. Techniques for Updating Pedestrian Network Data Including Facilities and Obstructions Information for Transportation of Vulnerable People

    PubMed Central

    Park, Seula; Bang, Yoonsik; Yu, Kiyun

    2015-01-01

    Demand for a Pedestrian Navigation Service (PNS) is on the rise. To provide a PNS for the transportation of vulnerable people, more detailed information of pedestrian facilities and obstructions should be included in Pedestrian Network Data (PND) used for PNS. Such data can be constructed efficiently by collecting GPS trajectories and integrating them with the existing PND. However, these two kinds of data have geometric differences and topological inconsistencies that need to be addressed. In this paper, we provide a methodology for integrating pedestrian facilities and obstructions information with an existing PND. At first we extracted the significant points from user-collected GPS trajectory by identifying the geometric difference index and attributes of each point. Then the extracted points were used to make an initial solution of the matching between the trajectory and the PND. Two geometrical algorithms were proposed and applied to reduce two kinds of errors in the matching: on dual lines and on intersections. Using the final solution for the matching, we reconstructed the node/link structure of PND including the facilities and obstructions information. Finally, performance was assessed with a test site and 79.2% of the collected data were correctly integrated with the PND. PMID:26404307

  13. Factors associated with hit-and-run pedestrian fatalities and driver identification.

    PubMed

    MacLeod, Kara E; Griswold, Julia B; Arnold, Lindsay S; Ragland, David R

    2012-03-01

    As hit-and-run crashes account for a significant proportion of pedestrian fatalities, a better understanding of these crash types will assist efforts to reduce these fatalities. Of the more than 48,000 pedestrian deaths that were recorded in the United States between 1998 and 2007, 18.1% of them were caused by hit-and-run drivers. Using national data on single pedestrian-motor vehicle fatal crashes (1998-2007), logistic regression analyses were conducted to identify factors related to hit-and-run and to identify factors related to the identification of the hit-and-run driver. Results indicate an increased risk of hit-and-run in the early morning, poor light conditions, and on the weekend. There may also be an association between the type of victim and the likelihood of the driver leaving and being identified. Results also indicate that certain driver characteristics, behavior, and driving history are associated with hit-and-run. Alcohol use and invalid license were among the leading driver factor associated with an increased risk of hit-and-run. Prevention efforts that address such issues could substantially reduce pedestrian fatalities as a result of hit-and-run. However, more information about this driver population may be necessary. PMID:22269520

  14. Developing a self-reporting method to measure pedestrian behaviors at all ages.

    PubMed

    Granié, Marie-Axelle; Pannetier, Marjorie; Guého, Ludivine

    2013-01-01

    The objective of this study was to develop and validate a self-reporting scale to measure injury risk behaviors among pedestrians of all ages. The Pedestrian Behavior Scale (PBS) was developed that included 47 items enabling respondents to evaluate the frequency with which they had different types of pedestrian behaviors. The validation study was carried out on 343 participants (126 men and 217 women) between the ages of 15 and 78. Factor analyses were used to differentiate between 4 axes. Factor 1, "transgression", included items concerning offence of legal rules and errors. Factor 2 included "lapses" items. Factor 3 comprised "aggressive behavior" items and factor 4 included "positive behavior" items. A revised version of the PBS with 20 items was produced by selecting those items that loaded most strongly on the four factors. The 20-item version had good internal reliability. The effects of demographic and mobility variables on the PBS scores were investigated. This instrument will be useful in measuring the frequency of these different types of behaviors among the pedestrians who are most at risk, analyzing the psychological factors used to predict PBS scores and thus better adapt preventive actions to the different populations of vulnerable road users of all ages. PMID:22836115

  15. Impact of a pilot walking school bus intervention on children's pedestrian safety behaviors: a pilot study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Walking school buses (WSB) increased children's physical activity, but impact on pedestrian safety behaviors (PSB) is unknown. We tested the feasibility of a protocol evaluating changes to PSB during a WSB program. Outcomes were school-level street crossing PSB prior to (Time 1) and during weeks 4–5...

  16. Veering by Blind Pedestrians: Individual Differences and Their Implications for Instruction.

    ERIC Educational Resources Information Center

    Guth, D.; LaDuke, E.

    1995-01-01

    This article reports the measurement of the "veering tendency" of 4 blind pedestrians over 3 15-trial test sessions. Findings illustrate between-subject and within-subject differences in patterns of veering, and the implications of these differences for orientation and mobility instruction are discussed. (Author)

  17. Identifying and tracking pedestrians based on sensor fusion and motion stability predictions.

    PubMed

    Musleh, Basam; García, Fernando; Otamendi, Javier; Armingol, José Maria; de la Escalera, Arturo

    2010-01-01

    The lack of trustworthy sensors makes development of Advanced Driver Assistance System (ADAS) applications a tough task. It is necessary to develop intelligent systems by combining reliable sensors and real-time algorithms to send the proper, accurate messages to the drivers. In this article, an application to detect and predict the movement of pedestrians in order to prevent an imminent collision has been developed and tested under real conditions. The proposed application, first, accurately measures the position of obstacles using a two-sensor hybrid fusion approach: a stereo camera vision system and a laser scanner. Second, it correctly identifies pedestrians using intelligent algorithms based on polylines and pattern recognition related to leg positions (laser subsystem) and dense disparity maps and u-v disparity (vision subsystem). Third, it uses statistical validation gates and confidence regions to track the pedestrian within the detection zones of the sensors and predict their position in the upcoming frames. The intelligent sensor application has been experimentally tested with success while tracking pedestrians that cross and move in zigzag fashion in front of a vehicle. PMID:22163639

  18. A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles

    PubMed Central

    Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

    2010-01-01

    The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted. PMID:21379367

  19. Identifying and Tracking Pedestrians Based on Sensor Fusion and Motion Stability Predictions

    PubMed Central

    Musleh, Basam; García, Fernando; Otamendi, Javier; Armingol, José Mª; de la Escalera, Arturo

    2010-01-01

    The lack of trustworthy sensors makes development of Advanced Driver Assistance System (ADAS) applications a tough task. It is necessary to develop intelligent systems by combining reliable sensors and real-time algorithms to send the proper, accurate messages to the drivers. In this article, an application to detect and predict the movement of pedestrians in order to prevent an imminent collision has been developed and tested under real conditions. The proposed application, first, accurately measures the position of obstacles using a two-sensor hybrid fusion approach: a stereo camera vision system and a laser scanner. Second, it correctly identifies pedestrians using intelligent algorithms based on polylines and pattern recognition related to leg positions (laser subsystem) and dense disparity maps and u-v disparity (vision subsystem). Third, it uses statistical validation gates and confidence regions to track the pedestrian within the detection zones of the sensors and predict their position in the upcoming frames. The intelligent sensor application has been experimentally tested with success while tracking pedestrians that cross and move in zigzag fashion in front of a vehicle. PMID:22163639

  20. Arizona Traffic Safety Education, K-8. Pedestrian Safety, Grades K-1.

    ERIC Educational Resources Information Center

    Mesa Public Schools, AZ.

    One in a series designed to assist Arizona elementary and junior high school teachers in developing children's traffic safety skills, this curriculum guide contains thirteen lessons on pedestrian safety for use in kindergarten and grade 1. Introductory information provided for the teacher includes basic highway safety concepts, stressing…

  1. 49 CFR 571.131 - Standard No. 131; School bus pedestrian safety devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 131; School bus pedestrian safety devices. 571.131 Section 571.131 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle...

  2. Examining the Impact of Traffic Environment and Executive Functioning on Children's Pedestrian Behaviors

    ERIC Educational Resources Information Center

    Barton, Benjamin K.; Morrongiello, Barbara A.

    2011-01-01

    The process of integrating visual information and planning a safe crossing is cognitively demanding for many young children. We assessed relations between traffic characteristics, aspects of children's executive functioning (EF), and pedestrian behavior, with the aim being to determine whether well-developed EF would predict safer pedestrian…

  3. 11. DETAIL VIEW OF RIVER BANK AND PEDESTRIAN/BICYCLE PATH UNDER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF RIVER BANK AND PEDESTRIAN/BICYCLE PATH UNDER THE GLENDALE BOULEVARD (FOREGROUND) AND HYPERION BOULEVARD OVERCROSSINGS. LOOKING SOUTH. - Glendale-Hyperion Viaduct, Spanning Golden State Freeway (I-5) & Los Angeles River at Glendale Boulevard, Los Angeles, Los Angeles County, CA

  4. West 73rd Street pedestrian underpass, with spur of old Miller ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    West 73rd Street pedestrian underpass, with spur of old Miller Highway, Trump Place towers in background, looking south. - Henry Hudson Parkway, Extending 11.2 miles from West 72nd Street to Bronx-Westchester border, New York County, NY

  5. Techniques for Updating Pedestrian Network Data Including Facilities and Obstructions Information for Transportation of Vulnerable People.

    PubMed

    Park, Seula; Bang, Yoonsik; Yu, Kiyun

    2015-01-01

    Demand for a Pedestrian Navigation Service (PNS) is on the rise. To provide a PNS for the transportation of vulnerable people, more detailed information of pedestrian facilities and obstructions should be included in Pedestrian Network Data (PND) used for PNS. Such data can be constructed efficiently by collecting GPS trajectories and integrating them with the existing PND. However, these two kinds of data have geometric differences and topological inconsistencies that need to be addressed. In this paper, we provide a methodology for integrating pedestrian facilities and obstructions information with an existing PND. At first we extracted the significant points from user-collected GPS trajectory by identifying the geometric difference index and attributes of each point. Then the extracted points were used to make an initial solution of the matching between the trajectory and the PND. Two geometrical algorithms were proposed and applied to reduce two kinds of errors in the matching: on dual lines and on intersections. Using the final solution for the matching, we reconstructed the node/link structure of PND including the facilities and obstructions information. Finally, performance was assessed with a test site and 79.2% of the collected data were correctly integrated with the PND. PMID:26404307

  6. Efficient pedestrian detection from aerial vehicles with object proposals and deep convolutional neural networks

    NASA Astrophysics Data System (ADS)

    Minnehan, Breton; Savakis, Andreas

    2016-05-01

    As Unmanned Aerial Systems grow in numbers, pedestrian detection from aerial platforms is becoming a topic of increasing importance. By providing greater contextual information and a reduced potential for occlusion, the aerial vantage point provided by Unmanned Aerial Systems is highly advantageous for many surveillance applications, such as target detection, tracking, and action recognition. However, due to the greater distance between the camera and scene, targets of interest in aerial imagery are generally smaller and have less detail. Deep Convolutional Neural Networks (CNN's) have demonstrated excellent object classification performance and in this paper we adopt them to the problem of pedestrian detection from aerial platforms. We train a CNN with five layers consisting of three convolution-pooling layers and two fully connected layers. We also address the computational inefficiencies of the sliding window method for object detection. In the sliding window configuration, a very large number of candidate patches are generated from each frame, while only a small number of them contain pedestrians. We utilize the Edge Box object proposal generation method to screen candidate patches based on an "objectness" criterion, so that only regions that are likely to contain objects are processed. This method significantly reduces the number of image patches processed by the neural network and makes our classification method very efficient. The resulting two-stage system is a good candidate for real-time implementation onboard modern aerial vehicles. Furthermore, testing on three datasets confirmed that our system offers high detection accuracy for terrestrial pedestrian detection in aerial imagery.

  7. Pedestrian overpass at West 176th Street, over Riverside Drive exit, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pedestrian overpass at West 176th Street, over Riverside Drive exit, connecting Haven Avenue to Fort Washington Park. George Washington Bridge in background, looking north. - Henry Hudson Parkway, Extending 11.2 miles from West 72nd Street to Bronx-Westchester border, New York County, NY

  8. 49 CFR 571.131 - Standard No. 131; School bus pedestrian safety devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...(a) and 1 CFR part 51. Copies may be obtained from the Society of Automotive Engineers, 400... buses to improve the safety of pedestrians in the vicinity of stopped school buses. S2. Purpose. The purpose of this standard is to reduce deaths and injuries by minimizing the likelihood of vehicles...

  9. Finite element analysis of knee injury risks in car-to-pedestrian impacts.

    PubMed

    Nagasaka, Kei; Mizuno, Koji; Tanaka, Eiichi; Yamamoto, Sota; Iwamoto, Masami; Miki, Kazuo; Kajzer, Janusz

    2003-12-01

    In vehicle-pedestrian collisions, lower extremities of pedestrians are frequently injured by vehicle front structures. In this study, a finite element (FE) model of THUMS (total human model for safety) was modified in order to assess injuries to a pedestrian lower extremity. Dynamic impact responses of the knee joint of the FE model were validated on the basis of data from the literature. Since in real-world accidents, the vehicle bumper can impact the lower extremities in various situations, the relations between lower extremity injury risk and impact conditions, such as between impact location, angle, and impactor stiffness, were analyzed. The FE simulation demonstrated that the motion of the lower extremity may be classified into a contact effect of the impactor and an inertia effect from a thigh or leg. In the contact phase, the stress of the bone is high in the area contacted by the impactor, which can cause fracture. Thus, in this phase the impactor stiffness affects the fracture risk of bone. In the inertia phase, the behavior of the lower extremity depends on the impact locations and angles, and the knee ligament forces become high according to the lower extremity behavior. The force of the collateral ligament is high compared with other knee ligaments, due to knee valgus motions in vehicle-pedestrian collisions. PMID:14630583

  10. An Analysis of the Safety Issues Involving Local School Children as Pedestrians. Revised.

    ERIC Educational Resources Information Center

    Ducote, Kenneth J.

    The New Orleans Public Schools' Department of Planning has been concerned with school children as pedestrians for the past five years. The safety issues include the streets, the drivers, and the children. First, the streets contribute to the hazard because many major streets traverse residential areas; many streets serve as major commuter…

  11. Posture estimation for improved photogrammetric localization of pedestrians in monocular infrared imagery

    NASA Astrophysics Data System (ADS)

    Kundegorski, Mikolaj E.; Breckon, Toby P.

    2015-10-01

    Target tracking complexity within conventional video imagery can be fundamentally attributed to the ambiguity associated with actual 3D scene position of a given tracked object in relation to its observed position in 2D image space. Recent work, within thermal-band infrared imagery, has tackled this challenge head on by returning to classical photogrammetry as a means of recovering the true 3D position of pedestrian targets. A key limitation in such approaches is the assumption of posture - that the observed pedestrian is at full height stance within the scene. Whilst prior work has shown the effects of statistical height variation to be negligible, variations in the posture of the target may still pose a significant source of potential error. Here we present a method that addresses this issue via the use of Support Vector Machine (SVM) regression based pedestrian posture estimation operating on Histogram of Orientated Gradient (HOG) feature descriptors. Within an existing tracking framework, we demonstrate improved target localization that is independent of variations in target posture (i.e. behaviour) and within the statistical error bounds of prior work for pedestrian height posture varying from 0.4-2.4m over a distance to target range of 7-30m.

  12. Impact of a pilot Walking School Bus intervention on children’s pedestrian safety behaviors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Walking School Buses (WSB) are groups of children, led to and from school by parents or other adults, in which children are picked up at designated "bus stops." Pedestrian safety should be taught and modeled by the adults on the walk to school. WSB programs have been reported to increase children’s ...

  13. 49 CFR 571.131 - Standard No. 131; School bus pedestrian safety devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Standard No. 131; School bus pedestrian safety devices. 571.131 Section 571.131 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle...

  14. 49 CFR 571.131 - Standard No. 131; School bus pedestrian safety devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... vehicle safety standard 125, Warning Devices, (49 CFR 571.125), the retroreflective materials shall meet...) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE SAFETY STANDARDS Federal Motor Vehicle Safety Standards § 571.131 Standard No. 131; School bus pedestrian...

  15. Needs and Problems of Older Drivers and Pedestrians: An Exploratory Study with Teaching/Learning Implications.

    ERIC Educational Resources Information Center

    Winter, Darlene J.

    1984-01-01

    Reviews the demographics related to drivers and pedestrians 55 years and over, identifying and addressing their special traffic problems and needs. Implications of alcohol and other drug use and physical, cognitive, psychological, and environmental factors that influence learning and performance are addressed as they relate to traffic safety…

  16. A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles.

    PubMed

    Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

    2011-03-01

    The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted. PMID:21379367

  17. An Anchor-Based Pedestrian Navigation Approach Using Only Inertial Sensors.

    PubMed

    Gu, Yang; Song, Qian; Li, Yanghuan; Ma, Ming; Zhou, Zhimin

    2016-01-01

    In inertial-based pedestrian navigation, anchors can effectively compensate the positioning errors originating from deviations of Inertial Measurement Units (IMUs), by putting constraints on pedestrians' motions. However, these anchors often need to be deployed beforehand, which can greatly increase system complexity, rendering it unsuitable for emergency response missions. In this paper, we propose an anchor-based pedestrian navigation approach without any additional sensors. The anchors are defined as the intersection points of perpendicular corridors and are considered characteristics of building structures. In contrast to these real anchors, virtual anchors are extracted from the pedestrian's trajectory and are considered as observations of real anchors, which can accordingly be regarded as inferred building structure characteristics. Then a Rao-Blackwellized particle filter (RBPF) is used to solve the joint estimation of positions (trajectory) and maps (anchors) problem. Compared with other building structure-based methods, our method has two advantages. The assumption on building structure is minimum and valid in most cases. Even if the assumption does not stand, the method will not lead to positioning failure. Several real-scenario experiments are conducted to validate the effectiveness and robustness of the proposed method. PMID:26959031

  18. 49 CFR 571.131 - Standard No. 131; School bus pedestrian safety devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... vehicle safety standard 125, Warning Devices, (49 CFR 571.125), the retroreflective materials shall meet... 49 Transportation 6 2013-10-01 2013-10-01 false Standard No. 131; School bus pedestrian safety...) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR VEHICLE...

  19. Obstructive Sleep Apnea Syndrome (OSAS) Increases Pedestrian Injury Risk in Children

    PubMed Central

    Avis, Kristin T.; Gamble, Karen L.; Schwebel, David C

    2014-01-01

    Objectives To evaluate pedestrian behavior, including reaction time, impulsivity, risk-taking, attention, and decision-making, in children with obstructive sleep apnea syndrome (OSAS) compared with healthy controls. Study design Using a case control design, sixty 8- to 16-year-olds with newly diagnosed and untreated OSAS engaged in a virtual reality pedestrian environment. Sixty-one healthy children matched using a yoke-control procedure by age, race, gender and household income served as controls. Results Children with OSAS were riskier pedestrians than healthy children of the same age, race, and sex. Children with OSAS waited less time to cross (p<.01). The groups did not differ in looking at oncoming traffic or taking longer to decide to cross. Conclusions Results suggest OSAS may have significant consequences on children’s daytime functioning in a critical domain of personal safety, pedestrian skills. Children with OSAS appeared to have greater impulsivity when crossing streets. Results highlight the need for heightened awareness of the consequences of untreated sleep disorders and identify a possible target for pediatric injury prevention. PMID:25444002

  20. Safety Action; Traffic and Pedestrian Safety. A Guide for Teachers in the Elementary Schools.

    ERIC Educational Resources Information Center

    Department of Transportation, Washington, DC.

    GRADES OR AGES: Elementary, grades 1-6. SUBJECT MATTER: Safety action, traffic and pedestrian safety. ORGANIZATION AND PHYSICAL APPEARANCE: After introductory material explaining the philosophy of the guide, the elementary school child, characteristics of children as related to safety, and the responsibility of the safety team, the guide has…

  1. Exploring the application of latent class cluster analysis for investigating pedestrian crash injury severities in Switzerland.

    PubMed

    Sasidharan, Lekshmi; Wu, Kun-Feng; Menendez, Monica

    2015-12-01

    One of the major challenges in traffic safety analyses is the heterogeneous nature of safety data, due to the sundry factors involved in it. This heterogeneity often leads to difficulties in interpreting results and conclusions due to unrevealed relationships. Understanding the underlying relationship between injury severities and influential factors is critical for the selection of appropriate safety countermeasures. A method commonly employed to address systematic heterogeneity is to focus on any subgroup of data based on the research purpose. However, this need not ensure homogeneity in the data. In this paper, latent class cluster analysis is applied to identify homogenous subgroups for a specific crash type-pedestrian crashes. The manuscript employs data from police reported pedestrian (2009-2012) crashes in Switzerland. The analyses demonstrate that dividing pedestrian severity data into seven clusters helps in reducing the systematic heterogeneity of the data and to understand the hidden relationships between crash severity levels and socio-demographic, environmental, vehicle, temporal, traffic factors, and main reason for the crash. The pedestrian crash injury severity models were developed for the whole data and individual clusters, and were compared using receiver operating characteristics curve, for which results favored clustering. Overall, the study suggests that latent class clustered regression approach is suitable for reducing heterogeneity and revealing important hidden relationships in traffic safety analyses. PMID:26476192

  2. Dynamic route guidance strategy in a two-route pedestrian-vehicle mixed traffic flow system

    NASA Astrophysics Data System (ADS)

    Liu, Mianfang; Xiong, Shengwu; Li, Bixiang

    2016-05-01

    With the rapid development of transportation, traffic questions have become the major issue for social, economic and environmental aspects. Especially, during serious emergencies, it is very important to alleviate road traffic congestion and improve the efficiency of evacuation to reduce casualties, and addressing these problems has been a major task for the agencies responsible in recent decades. Advanced road guidance strategies have been developed for homogeneous traffic flows, or to reduce traffic congestion and enhance the road capacity in a symmetric two-route scenario. However, feedback strategies have rarely been considered for pedestrian-vehicle mixed traffic flows with variable velocities and sizes in an asymmetric multi-route traffic system, which is a common phenomenon in many developing countries. In this study, we propose a weighted road occupancy feedback strategy (WROFS) for pedestrian-vehicle mixed traffic flows, which considers the system equilibrium to ease traffic congestion. In order to more realistic simulating the behavior of mixed traffic objects, the paper adopted a refined and dynamic cellular automaton model (RDPV_CA model) as the update mechanism for pedestrian-vehicle mixed traffic flow. Moreover, a bounded rational threshold control was introduced into the feedback strategy to avoid some negative effect of delayed information and reduce. Based on comparisons with the two previously proposed strategies, the simulation results obtained in a pedestrian-vehicle traffic flow scenario demonstrated that the proposed strategy with a bounded rational threshold was more effective and system equilibrium, system stability were reached.

  3. Trajectory data analyses for pedestrian space-time activity study.

    PubMed

    Qi, Feng; Du, Fei

    2013-01-01

    It is well recognized that human movement in the spatial and temporal dimensions has direct influence on disease transmission(1-3). An infectious disease typically spreads via contact between infected and susceptible individuals in their overlapped activity spaces. Therefore, daily mobility-activity information can be used as an indicator to measure exposures to risk factors of infection. However, a major difficulty and thus the reason for paucity of studies of infectious disease transmission at the micro scale arise from the lack of detailed individual mobility data. Previously in transportation and tourism research detailed space-time activity data often relied on the time-space diary technique, which requires subjects to actively record their activities in time and space. This is highly demanding for the participants and collaboration from the participants greatly affects the quality of data(4). Modern technologies such as GPS and mobile communications have made possible the automatic collection of trajectory data. The data collected, however, is not ideal for modeling human space-time activities, limited by the accuracies of existing devices. There is also no readily available tool for efficient processing of the data for human behavior study. We present here a suite of methods and an integrated ArcGIS desktop-based visual interface for the pre-processing and spatiotemporal analyses of trajectory data. We provide examples of how such processing may be used to model human space-time activities, especially with error-rich pedestrian trajectory data, that could be useful in public health studies such as infectious disease transmission modeling. The procedure presented includes pre-processing, trajectory segmentation, activity space characterization, density estimation and visualization, and a few other exploratory analysis methods. Pre-processing is the cleaning of noisy raw trajectory data. We introduce an interactive visual pre-processing interface as well as an

  4. The Advocacy for Pedestrian Safety Study: Cluster Randomised Trial Evaluating a Political Advocacy Approach to Reduce Pedestrian Injuries in Deprived Communities

    PubMed Central

    Lyons, Ronan A.; Kendrick, Denise; Towner, Elizabeth M. L.; Coupland, Carol; Hayes, Mike; Christie, Nicola; Sleney, Judith; Jones, Sarah; Kimberlee, Richard; Rodgers, Sarah E.; Turner, Samantha; Brussoni, Mariana; Vinogradova, Yana; Sarvotham, Tinnu; Macey, Steven

    2013-01-01

    Objective To determine whether advocacy targeted at local politicians leads to action to reduce the risk of pedestrian injury in deprived areas. Design Cluster randomised controlled trial. Setting 239 electoral wards in 57 local authorities in England and Wales. Participants 617 elected local politicians. Interventions Intervention group politicians were provided with tailored information packs, including maps of casualty sites, numbers injured and a synopsis of effective interventions. Main outcome measures 25–30 months post intervention, primary outcomes included: electoral ward level: percentage of road traffic calmed; proportion with new interventions; school level: percentage with 20 mph zones, Safe Routes to School, pedestrian training or road safety education; politician level: percentage lobbying for safety measures. Secondary outcomes included politicians’ interest and involvement in injury prevention, and facilitators and barriers to implementation. Results Primary outcomes did not significantly differ: % difference in traffic calming (0.07, 95%CI: −0.07 to 0.20); proportion of schools with 20 mph zones (RR 1.47, 95%CI: 0.93 to 2.32), Safe Routes to School (RR 1.34, 95%CI: 0.83 to 2.17), pedestrian training (RR 1.23, 95%CI: 0.95 to 1.61) or other safety education (RR 1.16, 95%CI: 0.97 to 1.39). Intervention group politicians reported greater interest in child injury prevention (RR 1.09, 95%CI 1.03 to 1.16), belief in potential to help prevent injuries (RR 1.36, 95%CI 1.16 to 1.61), particularly pedestrian safety (RR 1.55, 95%CI 1.19 to 2.03). 63% of intervention politicians reported supporting new pedestrian safety schemes. The majority found the advocacy information surprising, interesting, effectively presented, and could identify suitable local interventions. Conclusions This study demonstrates the feasibility of an innovative approach to translational public health by targeting local politicians in a randomised controlled trial. The intervention

  5. Functional declines as predictors of risky street-crossing decisions in older pedestrians.

    PubMed

    Dommes, Aurélie; Cavallo, Viola; Oxley, Jennifer

    2013-10-01

    The experiment investigated the extent to which risky street-crossing decisions by older pedestrians can be explained by declines in functional abilities. Sixteen young (age 20-35), 17 younger-old (age 60-67), and 18 older-old (age 70-84) participants carried out a street-crossing task in a simulated two-way road environment and took a battery of tests assessing perceptual, cognitive, and motor abilities. Older-old pedestrians were more likely than young and younger-old participants to make decisions that would have led to collisions with approaching cars, especially when traffic coming from two directions was approaching at a high speed. Regression analyses identified several functional performance measures as predictors of these dangerous choices. Walking speed, which determined the time needed to cross, was shown to play the most important role. Time-to-arrival estimate, which informed the pedestrians about the time available for crossing, was found to be the second most predictive factor. Visual processing speed and visual attention abilities assessed via the UFOV® Test also came into play, allowing participants to focus their attention on the relevant available information and to make timely, correct decisions. Attention shifting was the fourth significant predictor, allowing pedestrians to adapt their crossing strategy to the oncoming road-traffic information. The results suggest that the greater risk of being involved in a collision as age increases calls for a multi-dimensional explanation combining age-related physical, perceptual, and cognitive performance declines. These findings have implications for improving older pedestrians' safety in terms of speed limits, road design, and training. PMID:23792612

  6. Systems-based approach to investigate unsafe pedestrian behaviour at level crossings.

    PubMed

    Stefanova, Teodora; Burkhardt, Jean-Marie; Filtness, Ashleigh; Wullems, Christian; Rakotonirainy, Andry; Delhomme, Patricia

    2015-08-01

    Crashes at level crossings are a major issue worldwide. In Australia, as well as in other countries, the number of crashes with vehicles has declined in the past years, while the number of crashes involving pedestrians seems to have remained unchanged. A systematic review of research related to pedestrian behaviour highlighted a number of important scientific gaps in current knowledge. The complexity of such intersections imposes particular constraints to the understanding of pedestrians' crossing behaviour. A new systems-based framework, called Pedestrian Unsafe Level Crossing framework (PULC) was developed. The PULC organises contributing factors to crossing behaviour on different system levels as per the hierarchical classification of Jens Rasmussen's Framework for Risk Management. In addition, the framework adapts James Reason's classification to distinguish between different types of unsafe behaviour. The framework was developed as a tool for collection of generalizable data that could be used to predict current or future system failures or to identify aspects of the system that require further safety improvement. To give it an initial support, the PULC was applied to the analysis of qualitative data from focus groups discussions. A total number of 12 pedestrians who regularly crossed the same level crossing were asked about their daily experience and their observations of others' behaviour which allowed the extraction and classification of factors associated with errors and violations. Two case studies using Rasmussen's AcciMap technique are presented as an example of potential application of the framework. A discussion on the identified multiple risk contributing factors and their interactions is provided, in light of the benefits of applying a systems approach to the understanding of the origins of individual's behaviour. Potential actions towards safety improvement are discussed. PMID:25996290

  7. Analysis of Spatio-Temporal Traffic Patterns Based on Pedestrian Trajectories

    NASA Astrophysics Data System (ADS)

    Busch, S.; Schindler, T.; Klinger, T.; Brenner, C.

    2016-06-01

    For driver assistance and autonomous driving systems, it is essential to predict the behaviour of other traffic participants. Usually, standard filter approaches are used to this end, however, in many cases, these are not sufficient. For example, pedestrians are able to change their speed or direction instantly. Also, there may be not enough observation data to determine the state of an object reliably, e.g. in case of occlusions. In those cases, it is very useful if a prior model exists, which suggests certain outcomes. For example, it is useful to know that pedestrians are usually crossing the road at a certain location and at certain times. This information can then be stored in a map which then can be used as a prior in scene analysis, or in practical terms to reduce the speed of a vehicle in advance in order to minimize critical situations. In this paper, we present an approach to derive such a spatio-temporal map automatically from the observed behaviour of traffic participants in everyday traffic situations. In our experiments, we use one stationary camera to observe a complex junction, where cars, public transportation and pedestrians interact. We concentrate on the pedestrians trajectories to map traffic patterns. In the first step, we extract trajectory segments from the video data. These segments are then clustered in order to derive a spatial model of the scene, in terms of a spatially embedded graph. In the second step, we analyse the temporal patterns of pedestrian movement on this graph. We are able to derive traffic light sequences as well as the timetables of nearby public transportation. To evaluate our approach, we used a 4 hour video sequence. We show that we are able to derive traffic light sequences as well as time tables of nearby public transportation.

  8. [Prevention of road accidents involving non-motorized traffic participants (pedestrians and cyclists) in Germany].

    PubMed

    Zwipp, H; Ernstberger, A; Groschupf, V; Günther, K P; Haase, M; Haasper, C; Hagemeister, C; Hannawald, L; Juhra, C; Leser, H; Lob, G; Maier, R; Seeck, A; Winkler, R; Otte, D

    2012-06-01

    During a 1-day workshop organized by the German Society of Orthopaedics and Traumatology (DGOU) 15 German accident researchers used different approaches to improve the effectiveness of accident prevention for pedestrians and bicyclists on German roads. The main results of this analysis show: Fatal injuries of pedestrians have been significantly reduced by 82% between 1970 (n=6.056) and 2007 (n=695). Similarly, fatalities of bicyclists have been reduced during the same time period from 1,835 to 425 which amount to almost 80%. However, the total number of injured cyclists increased almost twice, i.e. from 40,531 (in 1979) to 78,579 (in 2007) a fact that needs to be analyzed in more detail. Although scientifically proven to provide protection against severe head injuries, helmets are worn less frequently by adolescents and women as compared to younger children and men. Fatalities of bicyclists might be reduced by using Dobli mirrors which allow the truck driver to see the bicyclist when turning right. Recently developed sensors are able to detect pedestrians walking closely (<2.5 m) and warn the truck driver acoustically. Bicycle lanes should be planned for one direction only, separated from the pedestrian way and large enough (2.0 m are safer than 1.6 m). Traffic education for school beginners and younger children should be repeated to be effective. Training for elderly bicyclists in cities with heavy traffic would also be reasonable. Active security systems in cars like ESP (electronic stability program), BAS (brake assist system), special light systems for curves, and night vision utilities are most effective to prevent collision with pedestrians and bicyclists. TV spots for bicyclists could help to point out dangerous situations and the proven benefits of wearing a helmet in the same way as previous campaigns, e.g."The 7th Sense" for car drivers. PMID:22159502

  9. Traffic signatures in suspended dust at pedestrian levels in semiarid zones: Implications for human exposure

    NASA Astrophysics Data System (ADS)

    Meza-Figueroa, Diana; González-Grijalva, Belem; Del Río-Salas, Rafael; Coimbra, Rute; Ochoa-Landin, Lucas; Moreno-Rodríguez, Verónica

    2016-08-01

    Deeper knowledge on dust suspension processes along semiarid zones is critical for understanding potential impacts on human health. Hermosillo city, located in the heart of the Sonoran Desert was chosen to evaluate such impacts. A one-year survey of Total Suspended Particulate Matter (TSPM) was conducted at two different heights (pedestrian and rooftop level). The minimum values of TSPM were reported during monsoon season and winter. Maximum values showed a bimodal distribution, with major peaks associated with increase and decrease of temperature, as well as decreasing humidity. Concentrations of TSPM were significantly exceeded at pedestrian level (∼44% of analyzed days) when compared to roof level (∼18% of analyzed days). Metal concentrations of As, Pb, Cu, Sb, Be, Mg, Ni, and Co were higher at pedestrian level than at roof level. Pixel counting and interpretations based on scanning electron microscopy of dust filters showed a higher percentage of fine particulate fractions at pedestrian level. These fractions occur mainly as metal-enriched agglomerates resembling coarser particles. According to worldwide guidelines, particulate matter sampling should be conducted by monitoring particle sizes equal and inferior to PM10. However, this work suggests that such procedures may compromise risk assessment in semiarid environments, where coarse particles act as main carriers for emergent contaminants related to traffic. This effect is especially concerning at pedestrian level, leading to an underestimation of potential impacts of human exposure. This study brings forward novel aspects that are of relevance for those concerned with dust suspension processes across semiarid regions and related impact on human health.

  10. The Influence of Neck Muscle Tonus and Posture on Brain Tissue Strain in Pedestrian Head Impacts.

    PubMed

    Alvarez, Victor S; Halldin, Peter; Kleiven, Svein

    2014-11-01

    Pedestrians are one of the least protected groups in urban traffic and frequently suffer fatal head injuries. An important boundary condition for the head is the cervical spine, and it has previously been demonstrated that neck muscle activation is important for head kinematics during inertial loading. It has also been shown in a recent numerical study that a tensed neck musculature also has some influence on head kinematics during a pedestrian impact situation. The aim of this study was to analyze the influence on head kinematics and injury metrics during the isolated time of head impact by comparing a pedestrian with relaxed neck and a pedestrian with increased tonus. The human body Finite Element model THUMS Version 1.4 was connected to head and neck models developed at KTH and used in pedestrian-to-vehicle impact simulations with a generalized hood, so that the head would impact a surface with an identical impact response in all simulations. In order to isolate the influence of muscle tonus, the model was activated shortly before head impact so the head would have the same initial position prior to impact among different tonus. A symmetric and asymmetric muscle activation scheme that used high level of activation was used in order to create two extremes to investigate. It was found that for the muscle tones used in this study, the influence on the strain in the brain was very minor, in general about 1-14% change. A relatively large increase was observed in a secondary peak in maximum strains in only one of the simulated cases. PMID:26192950

  11. Mistakes or deliberate violations? A study into the origins of rule breaking at pedestrian train crossings.

    PubMed

    Freeman, James; Rakotonirainy, Andry

    2015-04-01

    Train pedestrian collisions are the most likely to result in severe injuries and fatalities when compared to other types of rail crossing accidents. However, there is currently scant research that has examined the origins of pedestrians' rule breaking at level crossings. As a result, this study examined the origins of pedestrians' rule breaking behaviour at crossings, with particular emphasis directed towards examining the factors associated with making errors versus deliberation violations. A total of 636 individuals volunteered to participate in the study and completed either an online or paper version of the questionnaire. Quantitative analysis of the data revealed that knowledge regarding crossing rules was high, although up to 18% of level crossing users were either unsure or did not know (in some circumstances) when it was legal to cross at a level crossing. Furthermore, 156 participants (24.52%) reported having intentionally violated the rules at level crossings and 3.46% (n=22) of the sample had previously made a mistake at a crossing. In regards to rule violators, males (particularly minors) were more likely to report breaking rules, and the most frequent occurrence was after the train had passed rather than before it arrives. Regression analysis revealed that males who frequently use pedestrian crossings and report higher sensation seeking traits are most likely to break the rules. This research provides evidence that pedestrians are more likely to deliberately violate rules (rather than make errors) at crossings and it illuminates high risk groups. This paper will further outline the study findings in regards to the development of countermeasures as well as provide direction for future research efforts in this area. PMID:25681804

  12. Pattern and distribution of pedestrian injuries in fatal road traffic accidental cases in Dharan, Nepal

    PubMed Central

    Mandal, Birendra Kumar; Yadav, Biswa Nath

    2014-01-01

    Background and Objectives: Road traffic injuries are one of the leading causes of death in the world. The present study aims at evaluation of pattern and distribution of injuries among pedestrians thereby planning successful measures to minimize fatalities. Materials and Methods: The present study was conducted in the Department of Forensic Medicine and Toxicology, B.P. Koirala Institute of Health Sciences, Dharan, Nepal. This study included 50 cases of pedestrian victims of fatal road traffic accident, brought for medico-legal postmortem examination. Results: Highest number (17 or 21.3%) of fatalities occurred in the 41-50 years age group followed by the age group 31-40 years (15 or 18.7%). Male victims outnumbered female resulting in male to female ratio of 1.8:1. Most of the pedestrians were illiterate (26 or 32.5%) followed by those who were educated up to primary school (14 or 17.5%). Nearly half of the cases (38 or 47.5%), four or more wheelers – heavy vehicles – were involved. Fracture was the most common type of injuries (55 or 28.9%) followed by laceration (50 or 26.3%). In 44 (55%) cases, primary impact injuries were noted, secondary impact injuries in 55 (68.7%) cases, and secondary injuries in 62 (77.5%) cases. More than one-fourth (22 or 27.5%) of the deaths were due to pelvic and extremities injuries. Conclusion: Pedestrians, people who travel by foot, wheelchair, stroller, or similar means, are most vulnerable users of the road. Before head out on foot for a stroll, power walk, or errand, there are important safety tips to remember. A greater awareness about traffic rules will go a long way in curbing the incidence of fatal pedestrian accidents. PMID:25097407

  13. Predicting pedestrian flow: a methodology and a proof of concept based on real-life data.

    PubMed

    Davidich, Maria; Köster, Gerta

    2013-01-01

    Building a reliable predictive model of pedestrian motion is very challenging: Ideally, such models should be based on observations made in both controlled experiments and in real-world environments. De facto, models are rarely based on real-world observations due to the lack of available data; instead, they are largely based on intuition and, at best, literature values and laboratory experiments. Such an approach is insufficient for reliable simulations of complex real-life scenarios: For instance, our analysis of pedestrian motion under natural conditions at a major German railway station reveals that the values for free-flow velocities and the flow-density relationship differ significantly from widely used literature values. It is thus necessary to calibrate and validate the model against relevant real-life data to make it capable of reproducing and predicting real-life scenarios. In this work we aim at constructing such realistic pedestrian stream simulation. Based on the analysis of real-life data, we present a methodology that identifies key parameters and interdependencies that enable us to properly calibrate the model. The success of the approach is demonstrated for a benchmark model, a cellular automaton. We show that the proposed approach significantly improves the reliability of the simulation and hence the potential prediction accuracy. The simulation is validated by comparing the local density evolution of the measured data to that of the simulated data. We find that for our model the most sensitive parameters are: the source-target distribution of the pedestrian trajectories, the schedule of pedestrian appearances in the scenario and the mean free-flow velocity. Our results emphasize the need for real-life data extraction and analysis to enable predictive simulations. PMID:24386186

  14. Simulation of car impact to pedestrian lower extremity: influence of different car-front shapes and dummy parameters on test results.

    PubMed

    Ishikawa, H; Kajzer, J; Ono, K; Sakurai, M

    1994-04-01

    Sled impact tests on mechanical substitutes for a pedestrian were conducted as a preliminary study for the purpose of developing a subsystem test procedure for the assessment of car-front aggressiveness to pedestrian legs. Four mechanical substitutes for a pedestrian were used in the test: the leg of a rotationally symmetrical pedestrian dummy (RSPD) as the representation of a subsystem, a HYBRID-II pedestrian dummy, a modified HYBRID-II pedestrian dummy equipped with a steel bar serving as knee joint, and a RSPD - HYBRID-IIP combined dummy in which the lower part of the RSPD and the upper part of the HYBRID-IIP were connected by a joint in such a way that the movements of the upper part were similar to those in cadaver tests. In the tests the following were evaluated: (i) the influence of vehicle shape on knee response and on vehicle impact force; (ii) the influence of the upper body mass on knee response and on vehicle impact forces; (iii) the influence of the bumper system on knee response, the kinematics of pedestrian mechanical substitute, and on vehicle impact forces; (iv) the influence of pedestrian mechanical substitute characteristics on its kinematics and knee response, and on vehicle impact forces. This paper describes a primary concept when subsystem test methods for the assessment of car-front aggressiveness to pedestrian legs in a car-pedestrian collision are considered. PMID:8198692

  15. Micrometeorological simulations to predict the impacts of heat mitigation strategies on pedestrian thermal comfort in a Los Angeles neighborhood

    NASA Astrophysics Data System (ADS)

    Taleghani, Mohammad; Sailor, David; Ban-Weiss, George A.

    2016-02-01

    The urban heat island impacts the thermal comfort of pedestrians in cities. In this paper, the effects of four heat mitigation strategies on micrometeorology and the thermal comfort of pedestrians were simulated for a neighborhood in eastern Los Angeles County. The strategies investigated include solar reflective ‘cool roofs’, vegetative ‘green roofs’, solar reflective ‘cool pavements’, and increased street-level trees. A series of micrometeorological simulations for an extreme heat day were carried out assuming widespread adoption of each mitigation strategy. Comparing each simulation to the control simulation assuming current land cover for the neighborhood showed that additional street-trees and cool pavements reduced 1.5 m air temperature, while cool and green roofs mostly provided cooling at heights above pedestrian level. However, cool pavements increased reflected sunlight from the ground to pedestrians at a set of unshaded receptor locations. This reflected radiation intensified the mean radiant temperature and consequently increased physiological equivalent temperature (PET) by 2.2 °C during the day, reducing the thermal comfort of pedestrians. At another set of receptor locations that were on average 5 m from roadways and underneath preexisting tree cover, cool pavements caused significant reductions in surface air temperatures and small changes in mean radiant temperature during the day, leading to decreases in PET of 1.1 °C, and consequent improvements in thermal comfort. For improving thermal comfort of pedestrians during the afternoon in unshaded locations, adding street trees was found to be the most effective strategy. However, afternoon thermal comfort improvements in already shaded locations adjacent to streets were most significant for cool pavements. Green and cool roofs showed the lowest impact on the thermal comfort of pedestrians since they modify the energy balance at roof level, above the height of pedestrians.

  16. Usability and Feasibility of an Internet-Based Virtual Pedestrian Environment to Teach Children to Cross Streets Safely

    PubMed Central

    Schwebel, David C.; McClure, Leslie A.; Severson, Joan

    2013-01-01

    Child pedestrian injury is a preventable global health challenge. Successful training efforts focused on child behavior, including individualized streetside training and training in large virtual pedestrian environments, are laborious and expensive. This study considers the usability and feasibility of a virtual pedestrian environment “game” application to teach children safe street-crossing behavior via the internet, a medium that could be broadly disseminated at low cost. Ten 7- and 8-year-old children participated. They engaged in an internet-based virtual pedestrian environment and completed a brief assessment survey. Researchers rated children's behavior while engaged in the game. Both self-report and researcher observations indicated the internet-based system was readily used by the children without adult support. The youth understood how to engage in the system and used it independently and attentively. The program also was feasible. It provided multiple measures of pedestrian safety that could be used for research or training purposes. Finally, the program was rated by children as engaging and educational. Researcher ratings suggested children used the program with minimal fidgeting or boredom. The pilot test suggests an internet-based virtual pedestrian environment offers a usable, feasible, engaging, and educational environment for child pedestrian safety training. If future research finds children learn the cognitive and perceptual skills needed to cross streets safely within it, internet-based training may provide a low-cost medium to broadly disseminate child pedestrian safety training. The concept may be generalized to other domains of health-related functioning such as teen driving safety, adolescent sexual risk-taking, and adolescent substance use. PMID:24678263

  17. Development of a Pedestrian Indoor Navigation System Based on Multi-Sensor Fusion and Fuzzy Logic Estimation Algorithms

    NASA Astrophysics Data System (ADS)

    Lai, Y. C.; Chang, C. C.; Tsai, C. M.; Lin, S. Y.; Huang, S. C.

    2015-05-01

    This paper presents a pedestrian indoor navigation system based on the multi-sensor fusion and fuzzy logic estimation algorithms. The proposed navigation system is a self-contained dead reckoning navigation that means no other outside signal is demanded. In order to achieve the self-contained capability, a portable and wearable inertial measure unit (IMU) has been developed. Its adopted sensors are the low-cost inertial sensors, accelerometer and gyroscope, based on the micro electro-mechanical system (MEMS). There are two types of the IMU modules, handheld and waist-mounted. The low-cost MEMS sensors suffer from various errors due to the results of manufacturing imperfections and other effects. Therefore, a sensor calibration procedure based on the scalar calibration and the least squares methods has been induced in this study to improve the accuracy of the inertial sensors. With the calibrated data acquired from the inertial sensors, the step length and strength of the pedestrian are estimated by multi-sensor fusion and fuzzy logic estimation algorithms. The developed multi-sensor fusion algorithm provides the amount of the walking steps and the strength of each steps in real-time. Consequently, the estimated walking amount and strength per step are taken into the proposed fuzzy logic estimation algorithm to estimates the step lengths of the user. Since the walking length and direction are both the required information of the dead reckoning navigation, the walking direction is calculated by integrating the angular rate acquired by the gyroscope of the developed IMU module. Both the walking length and direction are calculated on the IMU module and transmit to a smartphone with Bluetooth to perform the dead reckoning navigation which is run on a self-developed APP. Due to the error accumulating of dead reckoning navigation, a particle filter and a pre-loaded map of indoor environment have been applied to the APP of the proposed navigation system to extend its

  18. IVF: exploiting intensity variation function for high-performance pedestrian tracking in forward-looking infrared imagery

    NASA Astrophysics Data System (ADS)

    Lamberti, Fabrizio; Sanna, Andrea; Paravati, Gianluca; Belluccini, Luca

    2014-02-01

    Tracking pedestrian targets in forward-looking infrared video sequences is a crucial component of a growing number of applications. At the same time, it is particularly challenging, since image resolution and signal-to-noise ratio are generally very low, while the nonrigidity of the human body produces highly variable target shapes. Moreover, motion can be quite chaotic with frequent target-to-target and target-to-scene occlusions. Hence, the trend is to design ever more sophisticated techniques, able to ensure rather accurate tracking results at the cost of a generally higher complexity. However, many of such techniques might not be suitable for real-time tracking in limited-resource environments. This work presents a technique that extends an extremely computationally efficient tracking method based on target intensity variation and template matching originally designed for targets with a marked and stable hot spot by adapting it to deal with much more complex thermal signatures and by removing the native dependency on configuration choices. Experimental tests demonstrated that, by working on multiple hot spots, the designed technique is able to achieve the robustness of other common approaches by limiting drifts and preserving the low-computational footprint of the reference method.

  19. Full-duplex RoF link with broadband mm-wave signal in W-band based on WDM-PON access network with optical mm-wave local oscillator broadcasting

    NASA Astrophysics Data System (ADS)

    Ma, Jianxin; Zhang, Ruijiao; Li, Yanjie; Zhang, Qi; Yu, Jianguo

    2015-02-01

    A novel full-duplex link with an optical mm-wave local oscillator broadcasting for broadband millimeter (mm)-wave wireless access in W-band is proposed based on the WDM-PON-RoF. In our scheme, a universal optical mm-wave local oscillator in W-band is distributed over the whole network to up-convert the downlink IF optical signal, which not only improves the spectrum efficiency by reducing the bandwidth requirement of each downlink, but also decreases the degradation caused by the fiber chromatic dispersion. Moreover, since the incoherently down-converted uplink signal is modulated on the reused blank optical carrier extracted from the downlink signal, the base stations (BSs) need no optical source, and so its structure is simplified. The numerical simulation results agree well with the theoretical analysis and show that the proposed full-duplex link for the W-band wireless access based on WDM-PON-RoF maintains good performance with cost effective implement.

  20. Distraction and Pedestrian Safety: How Talking on the Phone, Texting, and Listening to Music Impact Crossing the Street

    PubMed Central

    Schwebel, David C.; Stavrinos, Despina; Byington, Katherine W.; Davis, Tiffany; O’Neal, Elizabeth E.; de Jong, Desiree

    2011-01-01

    As use of handheld multimedia devices has exploded globally, safety experts have begun to consider the impact of distraction while talking, text-messaging, or listening to music on traffic safety. This study was designed to test how talking on the phone, texting, and listening to music may influence pedestrian safety. 138 college students crossed an interactive, semi-immersive virtual pedestrian street. They were randomly assigned to one of four groups: crossing while talking on the phone, crossing while texting, crossing while listening to a personal music device, or crossing while undistracted. Participants distracted by music or texting were more likely to be hit by a vehicle in the virtual pedestrian environment than were undistracted participants. Participants in all three distracted groups were more likely to look away from the street environment (and look toward other places, such as their telephone or music device) than were undistracted participants. Findings were maintained after controlling for demographics, walking frequency, and media use frequency. Distraction from multimedia devices has a small but meaningful impact on college students’ pedestrian safety. Future research should consider the cognitive demands of pedestrian safety, and how those processes may be impacted by distraction. Policymakers might consider ways to protect distracted pedestrians from harm and to reduce the number of individuals crossing streets while distracted. PMID:22269509