WorldWideScience

Sample records for mph traffic speed

  1. Raising the speed limit from 75 to 80mph on Utah rural interstates: Effects on vehicle speeds and speed variance.

    Science.gov (United States)

    Hu, Wen

    2017-06-01

    In November 2010 and October 2013, Utah increased speed limits on sections of rural interstates from 75 to 80mph. Effects on vehicle speeds and speed variance were examined. Speeds were measured in May 2010 and May 2014 within the new 80mph zones, and at a nearby spillover site and at more distant control sites where speed limits remained 75mph. Log-linear regression models estimated percentage changes in speed variance and mean speeds for passenger vehicles and large trucks associated with the speed limit increase. Logistic regression models estimated effects on the probability of passenger vehicles exceeding 80, 85, or 90mph and large trucks exceeding 80mph. Within the 80mph zones and at the spillover location in 2014, mean passenger vehicle speeds were significantly higher (4.1% and 3.5%, respectively), as were the probabilities that passenger vehicles exceeded 80mph (122.3% and 88.5%, respectively), than would have been expected without the speed limit increase. Probabilities that passenger vehicles exceeded 85 and 90mph were non-significantly higher than expected within the 80mph zones. For large trucks, the mean speed and probability of exceeding 80mph were higher than expected within the 80mph zones. Only the increase in mean speed was significant. Raising the speed limit was associated with non-significant increases in speed variance. The study adds to the wealth of evidence that increasing speed limits leads to higher travel speeds and an increased probability of exceeding the new speed limit. Results moreover contradict the claim that increasing speed limits reduces speed variance. Although the estimated increases in mean vehicle speeds may appear modest, prior research suggests such increases would be associated with substantial increases in fatal or injury crashes. This should be considered by lawmakers considering increasing speed limits. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  2. Traffic speed management

    Directory of Open Access Journals (Sweden)

    Subotić Jovana Lj.

    2014-01-01

    Full Text Available Speed, and vehicles themselves, affect the level of service and road safety, quality of life, noise from traffic, the environment, health, air pollution, emission of carbon dioxide, global warming, the economy and consumption of non-renewable energy such as oil. Therefore, the speed management of the traffic of multiple significance and that should be primarily to provide effective and economical conditions of the modern and preventive protection of human life as the greatest treasure and then the material resources. The way to accomplish this is by using various (different measures such as: appropriate planning and projecting roads and streets, speed control, the legislation, enforcement, campaigns, education, advanced technologies (ITS.

  3. Dynamic speed feedback signs for rural traffic calming.

    Science.gov (United States)

    2013-10-01

    Small rural communities often lack the expertise and resources necessary to address speeding and the persistent challenge of slowing high-speed through traffic. The entrances to communities are especially problematic given that drivers must transitio...

  4. Traffic Speed Data Imputation Method Based on Tensor Completion

    Directory of Open Access Journals (Sweden)

    Bin Ran

    2015-01-01

    Full Text Available Traffic speed data plays a key role in Intelligent Transportation Systems (ITS; however, missing traffic data would affect the performance of ITS as well as Advanced Traveler Information Systems (ATIS. In this paper, we handle this issue by a novel tensor-based imputation approach. Specifically, tensor pattern is adopted for modeling traffic speed data and then High accurate Low Rank Tensor Completion (HaLRTC, an efficient tensor completion method, is employed to estimate the missing traffic speed data. This proposed method is able to recover missing entries from given entries, which may be noisy, considering severe fluctuation of traffic speed data compared with traffic volume. The proposed method is evaluated on Performance Measurement System (PeMS database, and the experimental results show the superiority of the proposed approach over state-of-the-art baseline approaches.

  5. Traffic speed data imputation method based on tensor completion.

    Science.gov (United States)

    Ran, Bin; Tan, Huachun; Feng, Jianshuai; Liu, Ying; Wang, Wuhong

    2015-01-01

    Traffic speed data plays a key role in Intelligent Transportation Systems (ITS); however, missing traffic data would affect the performance of ITS as well as Advanced Traveler Information Systems (ATIS). In this paper, we handle this issue by a novel tensor-based imputation approach. Specifically, tensor pattern is adopted for modeling traffic speed data and then High accurate Low Rank Tensor Completion (HaLRTC), an efficient tensor completion method, is employed to estimate the missing traffic speed data. This proposed method is able to recover missing entries from given entries, which may be noisy, considering severe fluctuation of traffic speed data compared with traffic volume. The proposed method is evaluated on Performance Measurement System (PeMS) database, and the experimental results show the superiority of the proposed approach over state-of-the-art baseline approaches.

  6. Improved road traffic emission inventories by adding mean speed distributions

    NARCIS (Netherlands)

    Smit, R.; Poelman, M.; Schrijver, J.

    2008-01-01

    Does consideration of average speed distributions on roads-as compared to single mean speed-lead to different results in emission modelling of large road networks? To address this question, a post-processing method is developed to predict mean speed distributions using available traffic data from a

  7. Modeling of speed distribution for mixed bicycle traffic flow

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2015-11-01

    Full Text Available Speed is a fundamental measure of traffic performance for highway systems. There were lots of results for the speed characteristics of motorized vehicles. In this article, we studied the speed distribution for mixed bicycle traffic which was ignored in the past. Field speed data were collected from Hangzhou, China, under different survey sites, traffic conditions, and percentages of electric bicycle. The statistics results of field data show that the total mean speed of electric bicycles is 17.09 km/h, 3.63 km/h faster and 27.0% higher than that of regular bicycles. Normal, log-normal, gamma, and Weibull distribution models were used for testing speed data. The results of goodness-of-fit hypothesis tests imply that the log-normal and Weibull model can fit the field data very well. Then, the relationships between mean speed and electric bicycle proportions were proposed using linear regression models, and the mean speed for purely electric bicycles or regular bicycles can be obtained. The findings of this article will provide effective help for the safety and traffic management of mixed bicycle traffic.

  8. SOME EMPIRICAL RELATIONS BETWEEN TRAVEL SPEED, TRAFFIC VOLUME AND TRAFFIC COMPOSITION IN URBAN ARTERIALS

    Directory of Open Access Journals (Sweden)

    Eleni I. VLAHOGIANNI, Ph.D.

    2007-01-01

    Full Text Available The effects of traffic mix (the percentage of cars, trucks, buses and so on are of particular interest in the speed-volume relationship in urban signalized arterials under various geometric and control characteristics. The paper presents some empirical observations on the relation between travel speed, traffic volume and traffic composition in urban signalized arterials. A methodology based on emerging self-organizing structures of neural networks to identify regions in the speed-volume relationship with respect to traffic composition and Bayesian networks to evaluate the effect of different types of motorized vehicles on prevailing traffic conditions is proposed. Results based on data from a large urban network indicate that the variability in traffic conditions can be described by eight regions in speed-volume relationship with respect to traffic composition. Further evaluation of the effect of motorized vehicles in each region separately indicates that the effect of traffic composition decreases with the onset of congestion. Moreover, taxis and motorcycles are the primary affecting parameter of the form of the speed-volume relationship in urban arterials.

  9. Simulation of load traffic and steeped speed control of conveyor

    Science.gov (United States)

    Reutov, A. A.

    2017-10-01

    The article examines the possibilities of the step control simulation of conveyor speed within Mathcad, Simulink, Stateflow software. To check the efficiency of the control algorithms and to more accurately determine the characteristics of the control system, it is necessary to simulate the process of speed control with real values of traffic for a work shift or for a day. For evaluating the belt workload and absence of spillage it is necessary to use empirical values of load flow in a shorter period of time. The analytical formulas for optimal speed step values were received using empirical values of load. The simulation checks acceptability of an algorithm, determines optimal parameters of regulation corresponding to load flow characteristics. The average speed and the number of speed switching during simulation are admitted as criteria of regulation efficiency. The simulation example within Mathcad software is implemented. The average conveyor speed decreases essentially by two-step and three-step control. A further increase in the number of regulatory steps decreases average speed insignificantly but considerably increases the intensity of the speed switching. Incremental algorithm of speed regulation uses different number of stages for growing and reducing load traffic. This algorithm allows smooth control of the conveyor speed changes with monotonic variation of the load flow. The load flow oscillation leads to an unjustified increase or decrease of speed. Work results can be applied at the design of belt conveyors with adjustable drives.

  10. Design and implementation of speed humps: supplement to national guidelines for traffic calming

    CSIR Research Space (South Africa)

    Emslie, I

    1997-03-01

    Full Text Available This report presents guidelines to assist local authorities and traffic engineers with a uniform approach to the implementation of speed humps. It is recommended that these guidelines be read in conjunction with The National Guidelines for Traffic...

  11. Cellular Automata Models of Traffic Behavior in Presence of Speed Breaking Structures

    International Nuclear Information System (INIS)

    Ramachandran, Parthasarathy

    2009-01-01

    In this article, we study traffic flow in the presence of speed breaking structures. The speed breakers are typically used to reduce the local speed of vehicles near certain institutions such as schools and hospitals. Through a cellular automata model we study the impact of such structures on global traffic characteristics. The simulation results indicate that the presence of speed breakers could reduce the global flow under moderate global densities. However, under low and high global density traffic regime the presence of speed breakers does not have an impact on the global flow. Further the speed limit enforced by the speed breaker creates a phase distinction. For a given global density and slowdown probability, as the speed limit enforced by the speed breaker increases, the traffic moves from the reduced flow phase to maximum flow phase. This underlines the importance of proper design of these structures to avoid undesired flow restrictions. (general)

  12. Variable Speed Limit (VSL) - Best Management Practice

    Science.gov (United States)

    2012-07-01

    The Variable Speed Limit (VSL) system on the I-4 corridor in Orlando was implemented by Florida Department of Transportation in 2008, and since its deployment, it was revealed that the majority of traffic exceeds the speed limit by more mph when the ...

  13. An algorithm for the estimation of road traffic space mean speeds from double loop detector data

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Diaz, M.; Perez Perez, I.

    2016-07-01

    Most algorithms trying to analyze or forecast road traffic rely on many inputs, but in practice, calculations are usually limited by the available data and measurement equipment. Generally, some of these inputs are substituted by raw or even inappropriate estimations, which in some cases come into conflict with the fundamentals of traffic flow theory. This paper refers to one common example of these bad practices. Many traffic management centres depend on the data provided by double loop detectors, which supply, among others, vehicle speeds. The common data treatment is to compute the arithmetic mean of these speeds over different aggregation periods (i.e. the time mean speeds). Time mean speed is not consistent with Edie’s generalized definitions of traffic variables, and therefore it is not the average speed which relates flow to density. This means that current practice begins with an error that can have negative effects in later studies and applications. The algorithm introduced in this paper enables easily the estimation of space mean speeds from the data provided by the loops. It is based on two key hypotheses: stationarity of traffic and log-normal distribution of the individual speeds in each time interval of aggregation. It could also be used in case of transient traffic as a part of any data fusion methodology. (Author)

  14. assessment of traffic flow on enugu highways using speed density

    African Journals Online (AJOL)

    HOD

    Corresponding author, tel: +234 – 806 – 435 – 0200 ... construction, maintenance and optimization of the highways using the ...... Research Part A: Policy and Practice 29(4), 273-281. 1995. ... relationships: Quality and Theory of Traffic Flow.

  15. High-speed and high-fidelity system and method for collecting network traffic

    Science.gov (United States)

    Weigle, Eric H [Los Alamos, NM

    2010-08-24

    A system is provided for the high-speed and high-fidelity collection of network traffic. The system can collect traffic at gigabit-per-second (Gbps) speeds, scale to terabit-per-second (Tbps) speeds, and support additional functions such as real-time network intrusion detection. The present system uses a dedicated operating system for traffic collection to maximize efficiency, scalability, and performance. A scalable infrastructure and apparatus for the present system is provided by splitting the work performed on one host onto multiple hosts. The present system simultaneously addresses the issues of scalability, performance, cost, and adaptability with respect to network monitoring, collection, and other network tasks. In addition to high-speed and high-fidelity network collection, the present system provides a flexible infrastructure to perform virtually any function at high speeds such as real-time network intrusion detection and wide-area network emulation for research purposes.

  16. 32 CFR 636.22 - Speed regulations.

    Science.gov (United States)

    2010-07-01

    ...). (d) The following special speed limits apply: (1) When passing troop formations, 10 miles per hour... vehicles and will obey the following off-road driving speeds: Day Driving: Trails, 16 MPH Cross County, 6 MPH Night Driving: Trails, 5 MPH (with headlights) Cross Country, 5 MPH Night Driving: Trails, 4 MPH...

  17. Matching Countermeasures to Driver Types and Speeding Behavior : Traffic Tech

    Science.gov (United States)

    2017-06-01

    Speeding is a common behavior; most drivers exceed the speed limit some of the time. It is also a complicated behavior that varies by driver and situation. Speeding-related crashes take a large annual toll in injuries, lost lives, and high economic c...

  18. Variable speed limit strategies analysis with mesoscopic traffic flow model based on complex networks

    Science.gov (United States)

    Li, Shu-Bin; Cao, Dan-Ni; Dang, Wen-Xiu; Zhang, Lin

    As a new cross-discipline, the complexity science has penetrated into every field of economy and society. With the arrival of big data, the research of the complexity science has reached its summit again. In recent years, it offers a new perspective for traffic control by using complex networks theory. The interaction course of various kinds of information in traffic system forms a huge complex system. A new mesoscopic traffic flow model is improved with variable speed limit (VSL), and the simulation process is designed, which is based on the complex networks theory combined with the proposed model. This paper studies effect of VSL on the dynamic traffic flow, and then analyzes the optimal control strategy of VSL in different network topologies. The conclusion of this research is meaningful to put forward some reasonable transportation plan and develop effective traffic management and control measures to help the department of traffic management.

  19. Traffic calming measures and their effect on the variation of speed

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalo Orden, H.

    2016-07-01

    In recent years the number of deaths and serious injuries is decreasing in Spain, but, although the reduction outside the cities has been very strong, inside the urban areas, it has been smaller. This is especially hard if you look at the most vulnerable road users such as pedestrians and cyclists. In many accidents the speed factor appears closely linked not only to the number, but also to the severity of the accidents suffered inside the urban areas. Therefore, a reduction in the speed would improve the road safety. There are different measures known as {sup t}raffic calming measures{sup w}hose objectives are to reduce both the number and severity of accidents that occur on urban areas, by reducing the traffic flow through the streets, as well as the speed of the vehicles. However, the efficiency in speed reduction of each measure is not entirely known. That's the reason why they are implanted, in many cases, with no technical basis. The aim of this article is to show the effectiveness in reducing speed of some of the traffic calming measures. To this effect, field measurements were done on street sections with different types of traffic calming measures, in different places of a city of Burgos, in the north of Spain. These measurements were compared with other ones sited on other streets sections of similar characteristics but without traffic calming measures. Finally the conclusions are shown and some recommendations for improving their effectiveness are given. (Author)

  20. Traffic violations in Guangdong Province of China: speeding and drunk driving.

    Science.gov (United States)

    Zhang, Guangnan; Yau, Kelvin K W; Gong, Xiangpu

    2014-03-01

    The number of speeding- and drunk driving-related injuries in China surged in the years immediately preceding 2004 and then began to decline. However, the percent decrease in the number of speeding and drunk driving incidents (decrease by 22%) is not proportional to the corresponding percent decrease in number of automobile accident-related injuries (decrease by 47%) from the year 2004 to 2010 (Traffic Management Bureau, Ministry of Public Security, Annual Statistical Reports on Road Traffic Accidents). Earlier studies have established traffic violations as one of the major risks threatening road safety. In this study, we examine in greater detail two important types of traffic violation events, speeding and drunk driving, and attempt to identify significant risk factors associated with these types of traffic violations. Risk factors in several different dimensions, including driver, vehicle, road and environmental factors, are considered. We analyze the speeding (N=11,055) and drunk driving (N=10,035) data 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 and are the only comprehensive and official source of traffic accident data in China. Significant risk factors associating with speeding and drunk driving are identified. We find that several factors are associated with a significantly higher probability of both speeding and drunk driving, particularly male drivers, private vehicles, the lack of street lighting at night and poor visibility. The impact of other specific and unique risk factors for either speeding or drunk driving, such as hukou, road type/grades, commercial vehicles, compulsory third party insurance and vehicle safety status, also require particular attention. Legislative or regulatory measures targeting different vehicle types and/or driver groups with respect to the various driver

  1. Effect of Traffic Noise and Relaxations Sounds on Pedestrian Walking Speed

    Directory of Open Access Journals (Sweden)

    Marek Franěk

    2018-04-01

    Full Text Available Exposure to noise in everyday urban life is considered to be an environmental stressor. A specific outcome of reactions to environmental stress is a fast pace of life that also includes a faster pedestrian walking speed. The present study examined the effect of listening to annoying acoustical stimuli (traffic noise compared with relaxation sounds (forest birdsong on walking speed in a real outdoor urban environment. The participants (N = 83 walked along an urban route of 1.8 km. They listened to either traffic noise or forest birdsong, or they walked without listening to any acoustical stimuli in the control condition. The results showed that participants listening to traffic noise walked significantly faster on the route than both the participants listening to forest birdsong sounds and the participants in the control condition. Participants who listened to forest birdsong walked slightly slower than those under control conditions; however, this difference was not significant. Analysis of the walk experience showed that participants who listened to forest birdsong during the walk liked the route more than those who listened to traffic sounds. The study demonstrated that exposure to traffic noise led to an immediate increase in walking speed. It was also shown that exposure to noise may influence participants’ perception of an environment. The same environment may be more liked in the absence of noise or in the presence of relaxation sounds. The study also documented the positive effect of listening to various kinds of relaxation sounds while walking in an outdoor environment with traffic noise.

  2. Speed uncertainty and speed regulation in conflict detection and resolution in Air Traffic Control

    OpenAIRE

    Archambault , Nicolas

    2004-01-01

    International audience; With the predicted increase of air traffic volume, new air traffic management models are under investigation in order to increase airspace capacity and keep low delays while maintaining transportation safety standards. One of the tasks implied is to solve conflicts, i.e. maintain a sufficient separation between aircraft. Conflict resolution relies on conflict detection ; indeed predicting aircraft trajectories within a time window allows to detect the conflicts and app...

  3. High-speed web attack detection through extracting exemplars from HTTP traffic

    KAUST Repository

    Wang, Wei

    2011-01-01

    In this work, we propose an effective method for high-speed web attack detection by extracting exemplars from HTTP traffic before the detection model is built. The smaller set of exemplars keeps valuable information of the original traffic while it significantly reduces the size of the traffic so that the detection remains effective and improves the detection efficiency. The Affinity Propagation (AP) is employed to extract the exemplars from the HTTP traffic. K-Nearest Neighbor(K-NN) and one class Support Vector Machine (SVM) are used for anomaly detection. To facilitate comparison, we also employ information gain to select key attributes (a.k.a. features) from the HTTP traffic for web attack detection. Two large real HTTP traffic are used to validate our methods. The extensive test results show that the AP based exemplar extraction significantly improves the real-time performance of the detection compared to using all the HTTP traffic and achieves a more robust detection performance than information gain based attribute selection for web attack detection. © 2011 ACM.

  4. FORECASTING OF PASSENGER TRAFFIC UPON IMPLEMENTATION OF HIGH-SPEED RUNNING

    Directory of Open Access Journals (Sweden)

    M. B. Kurhan

    2017-02-01

    Full Text Available Purpose. Forecasting of passenger traffic flows in the future is an essential and integral part of the complex process of designing of high-speed network (HSN. HSN direction and its parameters are determined by the volume of passenger traffic, the estimated value of which depends on the economic performance of the country, as well as the material status of citizens living in HSN concentration area, transport mobility of population, development of competing modes of transport and so on. The purpose of this work is to analyse the existing methods of passenger traffic forecasting, to evaluate errors of the existing models concerning determination of traffic volumes and to specify the scientific approach to the development of high-speed rail transport in Ukraine. Methodology. The existing forecasting methods are reduced to the following ones: Delphi approach, extrapolation method, factor and correlation analysis, simulation method. The method described in this paper is based on scientific approaches such as analysis – a comprehensive and detailed study of various aspects of the known forecasting methods, comparing of existing methods for establishing differences and similarities, as well as deduction – use of general knowledge to get the new particular one. Thus, the unified indicators determined for the country as a whole, such as gross domestic product, national income, total population and others cannot be used to forecast the traffic flow on specific areas of HSN construction. Therefore, it is necessary to move from the overall forecast to traffic volume forecast on particular direction. Findings. The conclusions are derived from the analysis of different approaches and methods of passenger flow forecasting. It is proposed to create typical techniques of traffic flow forecasting using modern mathematical methods that would allow avoiding unreasonable decisions and shortening project development time. The resulting recommendations will help

  5. An RFID-Based Intelligent Vehicle Speed Controller Using Active Traffic Signals

    Science.gov (United States)

    Pérez, Joshué; Seco, Fernando; Milanés, Vicente; Jiménez, Antonio; Díaz, Julio C.; de Pedro, Teresa

    2010-01-01

    These days, mass-produced vehicles benefit from research on Intelligent Transportation System (ITS). One prime example of ITS is vehicle Cruise Control (CC), which allows it to maintain a pre-defined reference speed, to economize on fuel or energy consumption, to avoid speeding fines, or to focus all of the driver’s attention on the steering of the vehicle. However, achieving efficient Cruise Control is not easy in roads or urban streets where sudden changes of the speed limit can happen, due to the presence of unexpected obstacles or maintenance work, causing, in inattentive drivers, traffic accidents. In this communication we present a new Infrastructure to Vehicles (I2V) communication and control system for intelligent speed control, which is based upon Radio Frequency Identification (RFID) technology for identification of traffic signals on the road, and high accuracy vehicle speed measurement with a Hall effect-based sensor. A fuzzy logic controller, based on sensor fusion of the information provided by the I2V infrastructure, allows the efficient adaptation of the speed of the vehicle to the circumstances of the road. The performance of the system is checked empirically, with promising results. PMID:22219692

  6. An RFID-based intelligent vehicle speed controller using active traffic signals.

    Science.gov (United States)

    Pérez, Joshué; Seco, Fernando; Milanés, Vicente; Jiménez, Antonio; Díaz, Julio C; de Pedro, Teresa

    2010-01-01

    These days, mass-produced vehicles benefit from research on Intelligent Transportation System (ITS). One prime example of ITS is vehicle Cruise Control (CC), which allows it to maintain a pre-defined reference speed, to economize on fuel or energy consumption, to avoid speeding fines, or to focus all of the driver's attention on the steering of the vehicle. However, achieving efficient Cruise Control is not easy in roads or urban streets where sudden changes of the speed limit can happen, due to the presence of unexpected obstacles or maintenance work, causing, in inattentive drivers, traffic accidents. In this communication we present a new Infrastructure to Vehicles (I2V) communication and control system for intelligent speed control, which is based upon Radio Frequency Identification (RFID) technology for identification of traffic signals on the road, and high accuracy vehicle speed measurement with a Hall effect-based sensor. A fuzzy logic controller, based on sensor fusion of the information provided by the I2V infrastructure, allows the efficient adaptation of the speed of the vehicle to the circumstances of the road. The performance of the system is checked empirically, with promising results.

  7. An RFID-Based Intelligent Vehicle Speed Controller Using Active Traffic Signals

    Directory of Open Access Journals (Sweden)

    Joshué Pérez

    2010-06-01

    Full Text Available These days, mass-produced vehicles benefit from research on Intelligent Transportation System (ITS. One prime example of ITS is vehicle Cruise Control (CC, which allows it to maintain a pre-defined reference speed, to economize on fuel or energy consumption, to avoid speeding fines, or to focus all of the driver’s attention on the steering of the vehicle. However, achieving efficient Cruise Control is not easy in roads or urban streets where sudden changes of the speed limit can happen, due to the presence of unexpected obstacles or maintenance work, causing, in inattentive drivers, traffic accidents. In this communication we present a new Infrastructure to Vehicles (I2V communication and control system for intelligent speed control, which is based upon Radio Frequency Identification (RFID technology for identification of traffic signals on the road, and high accuracy vehicle speed measurement with a Hall effect-based sensor. A fuzzy logic controller, based on sensor fusion of the information provided by the I2V infrastructure, allows the efficient adaptation of the speed of the vehicle to the circumstances of the road. The performance of the system is checked empirically, with promising results.

  8. Traffic

    International Nuclear Information System (INIS)

    Lichtblau, G.

    2001-01-01

    This chapter deals with passenger and freight traffic, public and private transportation, traffic related environmental impacts, future developments, traffic indicators, regional traffic planning, health costs due to road traffic related air pollution, noise pollution, measures and regulations for traffic control and fuels for traffic. In particular energy consumption, energy efficiency, pollutant emissions ( CO 2 , SO 2 , NO x , HC, CO, N 2 O, NH 3 and particulates) and environmental effects of the different types of traffic and different types of fuels are compared and studied. Legal regulations and measures for an effective traffic control are discussed. (a.n.)

  9. The development of a method to measure speed adaptation to traffic complexity: Identifying novice, unsafe, and overconfident drivers.

    NARCIS (Netherlands)

    Craen, S. de Twisk, D.A.M. Hagenzieker, M.P. Elffers, H. & Brookhuis, K.A.

    2008-01-01

    To monitor novice driver performance in the first years of solo driving, a test aimed at assessing speed adaptation to the traffic situation was developed and evaluated. The Adaptation Test consisted of 18 traffic scenes presented in two (almost) identical photographs, which differed in one single

  10. The development of a method to measure speed adaptation to traffic complexity : Identifying novice, unsafe, and overconfident drivers

    NARCIS (Netherlands)

    de Craen, Saskia; Twisk, Divera A. M.; Hagenzieker, Marjan P.; Elffers, Henk; Brookhuis, Karel A.

    To monitor novice driver performance in the first years of solo driving, a test aimed at assessing speed adaptation to the traffic situation was developed and evaluated. The Adaptation Test consisted of 18 traffic scenes presented in two (almost) identical photographs, which differed in one single

  11. Predicting Free Flow Speed and Crash Risk of Bicycle Traffic Flow Using Artificial Neural Network Models

    Directory of Open Access Journals (Sweden)

    Cheng Xu

    2015-01-01

    Full Text Available Free flow speed is a fundamental measure of traffic performance and has been found to affect the severity of crash risk. However, the previous studies lack analysis and modelling of impact factors on bicycles’ free flow speed. The main focus of this study is to develop multilayer back propagation artificial neural network (BPANN models for the prediction of free flow speed and crash risk on the separated bicycle path. Four different models with considering different combinations of input variables (e.g., path width, traffic condition, bicycle type, and cyclists’ characteristics were developed. 459 field data samples were collected from eleven bicycle paths in Hangzhou, China, and 70% of total samples were used for training, 15% for validation, and 15% for testing. The results show that considering the input variables of bicycle types and characteristics of cyclists will effectively improve the accuracy of the prediction models. Meanwhile, the parameters of bicycle types have more significant effect on predicting free flow speed of bicycle compared to those of cyclists’ characteristics. The findings could contribute for evaluation, planning, and management of bicycle safety.

  12. Variable Speed Limits: Strategies to Improve Safety and Traffic Parameters for a Bottleneck

    Directory of Open Access Journals (Sweden)

    M. Z. Hasanpour

    2017-04-01

    Full Text Available The primary purpose of the speed limit system is to enforce reasonable and safe speed. To reduce secondary problems such as accidents and queuing, Variable Speed Limits (VSL has been suggested. In this paper VSL is used to better safety and traffic parameters. Traffic parameters including speed, queue length and stopping time have been pondering. For VLS, an optimization decision tree algorithm with the function of microscopic simulation was used. The results in case of sub saturated, saturated and supersaturated at a bottleneck are examined and compared with the Allaby logic tree. The results show that the proposed decision tree shows an improved performance in terms of safety and comfort along the highway. The VSL pilot project is part of the Road Safety Improvement Program included in Iran’s road safety action plan that is in the research process in the BHRC Research Institute, Road and Housing & Urban Development Research that is planned for next 10-year Transportation safety view Plan.

  13. Evaluation of uncertainty of vehicle speed when autotechnical examination of traffic accidents

    Directory of Open Access Journals (Sweden)

    Kashkanov А.А.

    2016-08-01

    Full Text Available The existing methods and ways to measure vehicle speed, which can be used in autotechnical examination of road accidents, in order to identify ways to improve the peer review mechanism of emergencies are analyzed. To achieve the goal we propose to take measurement errors vehicle speed into account. Modern automated technology (GPS, EDR and ACN can reduce these errors, and with sufficient accuracy to determine the speed of the vehicle and other motion parameters and technical data that helps to quicken research in various stages of examination, but there are a number of objective problems hindering their widespread use in Ukraine. To solve these problems need to develop and improve existing methods of expert investigation of the circumstances of accidents based process automation capabilities fixing mechanism and the scene, measurements and calculations options vehicular traffic. This will increase the effectiveness of traditional methods and to minimize the influence of subjective factors.

  14. Paediatric slow-speed non-traffic fatalities: Victoria, Australia, 1985-1995.

    Science.gov (United States)

    Robinson, P; Nolan, T

    1997-11-01

    An important group of fatal incidents are slow-speed pedestrian non-traffic incidents to children, which account for 14% of accidental deaths from all causes in Victorian children under 5 years of age between 1985 and 1995, and 12% of pedestrian deaths of all ages. In Victoria, Australia, the database of the state Consultative Council on Obstetric and Paediatric Morbidity and Mortality was utilised to identify paediatric slow-speed pedestrian non-traffic-accident deaths in the local population. Additional data relating to the car and its driver, the child, and the circumstances of the incident were abstracted from records kept by the State Coroner and the Victorian compulsory third party traffic injury insurance organisation. Twenty eight Victorian children were identified who had died in one of three types of incident (driverless cars, child interacting with the vehicle and driver, and drivers who were unaware of the child's proximity). These incidents were more common in rural areas compared with urban, usually occurring at the child's home. The child was with or near an adult on all occasions. The vehicle was usually being driven by a relative, and was reversing in a higher proportion of 'unaware' incidents compared with the 'interactive' type. The association of 'off-road' family vehicles and trucks with these incidents appears to be increasing, especially in recent years. These findings suggest some countermeasures, including the separation of vehicle driveways from children's play areas, and object vicinity ultrasonic warning devices for vehicles.

  15. Efficient Computation of Separation-Compliant Speed Advisories for Air Traffic Arriving in Terminal Airspace

    Science.gov (United States)

    Sadovsky, Alexander V.; Davis, Damek; Isaacson, Douglas R.

    2012-01-01

    A class of problems in air traffic management asks for a scheduling algorithm that supplies the air traffic services authority not only with a schedule of arrivals and departures, but also with speed advisories. Since advisories must be finite, a scheduling algorithm must ultimately produce a finite data set, hence must either start with a purely discrete model or involve a discretization of a continuous one. The former choice, often preferred for intuitive clarity, naturally leads to mixed-integer programs, hindering proofs of correctness and computational cost bounds (crucial for real-time operations). In this paper, a hybrid control system is used to model air traffic scheduling, capturing both the discrete and continuous aspects. This framework is applied to a class of problems, called the Fully Routed Nominal Problem. We prove a number of geometric results on feasible schedules and use these results to formulate an algorithm that attempts to compute a collective speed advisory, effectively finite, and has computational cost polynomial in the number of aircraft. This work is a first step toward optimization and models refined with more realistic detail.

  16. A Vehicular Mobile Standard Instrument for Field Verification of Traffic Speed Meters Based on Dual-Antenna Doppler Radar Sensor.

    Science.gov (United States)

    Du, Lei; Sun, Qiao; Cai, Changqing; Bai, Jie; Fan, Zhe; Zhang, Yue

    2018-04-05

    Traffic speed meters are important legal measuring instruments specially used for traffic speed enforcement and must be tested and verified in the field every year using a vehicular mobile standard speed-measuring instrument to ensure speed-measuring performances. The non-contact optical speed sensor and the GPS speed sensor are the two most common types of standard speed-measuring instruments. The non-contact optical speed sensor requires extremely high installation accuracy, and its speed-measuring error is nonlinear and uncorrectable. The speed-measuring accuracy of the GPS speed sensor is rapidly reduced if the amount of received satellites is insufficient enough, which often occurs in urban high-rise regions, tunnels, and mountainous regions. In this paper, a new standard speed-measuring instrument using a dual-antenna Doppler radar sensor is proposed based on a tradeoff between the installation accuracy requirement and the usage region limitation, which has no specified requirements for its mounting distance and no limitation on usage regions and can automatically compensate for the effect of an inclined installation angle on its speed-measuring accuracy. Theoretical model analysis, simulated speed measurement results, and field experimental results compared with a GPS speed sensor with high accuracy showed that the dual-antenna Doppler radar sensor is effective and reliable as a new standard speed-measuring instrument.

  17. Comparison of Traffic Speed Before, During and After “Banci Lalu Lintas” at Federal Road ft005

    Directory of Open Access Journals (Sweden)

    Rahman R.

    2017-01-01

    Full Text Available Traffic engineering uses engineering methods and techniques to achieve the safe and time efficient movement of people and goods on roadways and it depends on traffic flow. The three main parameters of a traffic flow are volume, speed and density. Speed is an important transportation consideration because it relates to safety, time, comfort, convenience, and economics. This study is to show the difference of traffic speed for before, during and after a primary traffic survey called “Banci Lalu Lintas”. This study also is conducted at Federal Road FT005 with collaboration of Jabatan Kerja Raya (JKR. In achieving the goal for this study, traffic speed is recorded by using two methods which are manual method and Automatic Traffic Count (ATC. For before and after the survey, manual method is used and the data is collected for 15 minutes, while during the survey, ATC is used in collecting data for 24 hours per day in a week. The data obtained where the mean speed is recorded and is compared as well as analyzed between three categories which are before, during and after “Banci Lalu Lintas” and using statistical analysis. In result, the speed of vehicles for during the survey is the lowest compared to before and after survey where the differential percentage are 6.68% and 23.64% for before – during and during – after “Banci Lalu Lintas”. The study concluded that drivers tend to decrease their vehicles speed when there is an event or unexpected conditions on the road. The result is important for future development and safety of road in Malaysia.

  18. Control techniques for an automated mixed traffic vehicle

    Science.gov (United States)

    Meisenholder, G. W.; Johnston, A. R.

    1977-01-01

    The paper describes an automated mixed traffic vehicle (AMTV), a driverless low-speed tram designed to operate in mixed pedestrian and vehicular traffic. The vehicle is a six-passenger electric tram equipped with sensing and control which permit it to function on existing streets in an automatic mode. The design includes established wire-following techniques for steering and near-IR headway sensors. A 7-mph cruise speed is reduced to 2 mph or a complete stop in response to sensor (or passenger) inputs. The AMTV performance is evaluated by operation on a loop route and by simulation. Some necessary improvements involving sensors, sensor pattern, use of an audible signal, and control lag are discussed. It is suggested that appropriate modifications will eliminate collision incidents.

  19. Speed Distribution on Two-Lane Rural Highways with Mixed Traffic: A Case Study in North East India

    Science.gov (United States)

    Saha, Pritam; Roy, Nabanita; Sarkar, Ashoke Kumar; Pal, Manish

    2017-06-01

    This work focuses on minimising inaccuracies in distributional assumptions of speed data on two-lane roads with heterogeneous traffic to improve accuracy in capacity and level of service analysis. Accordingly, field study was conducted on a two-lane highway in India that exhibits heterogeneity in its traffic composition. Two distribution functions, namely, normal and logistic were examined for the observed speed data. The appropriate function was chosen using a methodology based on K-S test and field validation. Logistic distribution function was found to exhibit its aptness in describing speed under such traffic and was, thereby, considered in estimating the limiting speed of slower vehicles that tends to obstruct the flow of traffic. Vehicles that move at or below this speed cause delay to the faster ones resulting in formation of platoons at moderate and heavy flow when passing is restricted. Since the percent time-spent-following, a performance measure to assess level-of-service of two-lane highways, considers proportion of vehicles that are trapped inside platoons, it is imperative to estimate the limiting speed of slower vehicles correctly to approximate the delayed vehicles.

  20. Can the traffic locus of control (T-LOC) scale be successfully used to predict Swedish drivers' speeding behaviour?

    Science.gov (United States)

    Warner, Henriette Wallén; Ozkan, Türker; Lajunen, Timo

    2010-07-01

    The first aim of the present study was to examine the factor structure of the traffic locus of control (T-LOC) scale in a Swedish sample of drivers. The second aim was to examine if this scale can be used to predict drivers' speeding behaviour. A sample of Swedish car owners (N=223) completed a questionnaire including questions based on the traffic locus of control (T-LOC) scale as well as questions about their speeding behaviour. The results showed a five factor solution including own skills, own behaviour, other drivers, vehicle/environment and fate. Own behaviour and vehicle/environment could be used to predict drivers' speeding behaviour on roads with a 90 km/h speed limit while none of the variables included in the traffic locus of control (T-LOC) scale could be used to predict drivers' speeding behaviour on roads with a 50 km/h speed limit. On 90 km/h roads own behaviour was positively related to drivers' speeding behaviour while vehicle/environment was negatively related to their speeding behaviour. Copyright 2010 Elsevier Ltd. All rights reserved.

  1. Learning Traffic as Images: A Deep Convolutional Neural Network for Large-Scale Transportation Network Speed Prediction.

    Science.gov (United States)

    Ma, Xiaolei; Dai, Zhuang; He, Zhengbing; Ma, Jihui; Wang, Yong; Wang, Yunpeng

    2017-04-10

    This paper proposes a convolutional neural network (CNN)-based method that learns traffic as images and predicts large-scale, network-wide traffic speed with a high accuracy. Spatiotemporal traffic dynamics are converted to images describing the time and space relations of traffic flow via a two-dimensional time-space matrix. A CNN is applied to the image following two consecutive steps: abstract traffic feature extraction and network-wide traffic speed prediction. The effectiveness of the proposed method is evaluated by taking two real-world transportation networks, the second ring road and north-east transportation network in Beijing, as examples, and comparing the method with four prevailing algorithms, namely, ordinary least squares, k-nearest neighbors, artificial neural network, and random forest, and three deep learning architectures, namely, stacked autoencoder, recurrent neural network, and long-short-term memory network. The results show that the proposed method outperforms other algorithms by an average accuracy improvement of 42.91% within an acceptable execution time. The CNN can train the model in a reasonable time and, thus, is suitable for large-scale transportation networks.

  2. An evaluation of speed management measures in Bangladesh based upon alternative accident recording, speed measurements, and DOCTOR traffic conflict observations

    NARCIS (Netherlands)

    Horst, A.R.A. van der; Thierry, M.C.; Vet, J.M.; Rahman, A.F

    2016-01-01

    With 21,000 people annually killed in road traffic (estimated figure by World Health Organization), Bangladesh has one of the highest fatality rates in the world. Vulnerable road users (VRUs) account for over 50% of road traffic casualties, and 70% of casualties occur in rural areas. As in many Low

  3. An evaluation of speed management measures in Bangladesh based upon alternative accident recording, speed measurements, and DOCTOR traffic conflict observations

    NARCIS (Netherlands)

    Horst, A.R.A. van der; Thierry, M.C.; Vet, J.M.; Fazlur Rahman, A.K.M.

    2017-01-01

    With 21,000 people annually killed in road traffic (estimated figure by World Health Organization), Bangladesh has one of the highest fatality rates in the world. Vulnerable road users (VRUs) account for over 50% of road traffic casualties, and 70% of casualties occur in rural areas. As in many Low

  4. Modified Motor Vehicles Travel Speed Models on the Basis of Curb Parking Setting under Mixed Traffic Flow

    Directory of Open Access Journals (Sweden)

    Zhenyu Mei

    2012-01-01

    Full Text Available The ongoing controversy about in what condition should we set the curb parking has few definitive answers because comprehensive research in this area has been lacking. Our goal is to present a set of heuristic urban street speed functions under mixed traffic flow by taking into account impacts of curb parking. Two impacts have been defined to classify and quantify the phenomena of motor vehicles' speed dynamics in terms of curb parking. The first impact is called Space impact, which is caused by the curb parking types. The other one is the Time impact, which results from the driver maneuvering in or out of parking space. In this paper, based on the empirical data collected from six typical urban streets in Nanjing, China, two models have been proposed to describe these phenomena for one-way traffic and two-way traffic, respectively. An intensive experiment has been conducted in order to calibrate and validate these proposed models, by taking into account the complexity of the model parameters. We also provide guidelines in terms of how to cluster and calculate those models' parameters. Results from these models demonstrated promising performance of modeling motor vehicles' speed for mixed traffic flow under the influence of curb parking.

  5. Speed support through the intelligent vehicle : perspective, estimated effects and implementation aspects.[Deliverable of the Intelligent Vehicles project, part of the Traffic Management project within TRANSUMO (TRANsition to SUstainable MObility).

    NARCIS (Netherlands)

    Morsink, P. Goldenbeld, C. Dragutinovic, N. Marchau, V. Walta, L. & Brookhuis, K.

    2008-01-01

    Speed management is a central theme in traffic management, aiming to optimize traffic in terms of safety, efficiency and the environment, by reducing speeding and speed differences in traffic. Intelligent vehicles can perform tasks that conventional measures cannot do at all, or do less efficiently.

  6. High-speed web attack detection through extracting exemplars from HTTP traffic

    KAUST Repository

    Wang, Wei; Zhang, Xiangliang

    2011-01-01

    Vector Machine (SVM) are used for anomaly detection. To facilitate comparison, we also employ information gain to select key attributes (a.k.a. features) from the HTTP traffic for web attack detection. Two large real HTTP traffic are used to validate our

  7. Evaluation of the traffic safety benefits of a lower speed limit and restriction of trucks to use of right lane only on I-10 over the Atchafalaya Basin.

    Science.gov (United States)

    2012-01-01

    To improve traffic operation and safety, several states have implemented truck lane restriction and differential speed limit policies on freeways. In response to an 11-vehicle crash in September 2003, the Louisiana State Department of Transportation ...

  8. Metal accumulation in roadside soil in Melbourne, Australia: Effect of road age, traffic density and vehicular speed

    International Nuclear Information System (INIS)

    De Silva, Shamali; Ball, Andrew S.; Huynh, Trang; Reichman, Suzie M.

    2016-01-01

    Concentrations of vehicular emitted heavy metals in roadside soils result in long term environmental damage. This study assessed the relationships between traffic characteristics (traffic density, road age and vehicular speed) and roadside soil heavy metals. Significant levels were recorded for Cd (0.06–0.59 mg/kg), Cr (18–29 mg/kg), Cu (4–12 mg/kg), Ni (7–20 mg/kg), Mn (92–599 mg/kg), Pb (16–144 mg/kg) and Zn (10.36–88.75 mg/kg), with Mn concentrations exceeding the Ecological Investigation Level. Significant correlations were found between roadside soil metal concentration and vehicular speed (R = 0.90), road age (R = 0.82) and traffic density (R = 0.68). Recently introduced metals in automotive technology (e.g. Mn and Sb) were higher in younger roads, while the metals present for many years (e.g. Cd, Cu, Pb, Zn) were higher in medium and old age roads confirming the risk of significant metal deposition and soil metal retention in roadside soils. - Highlights: • Elevated metal concentrations were recorded from Melbourne roadside soils. • Mn and Sb tended to be higher in younger roads. • Cd, Cu, Pb and Zn were particularly elevated in medium and old age roads. • Accumulation of Ag, Co and Sb were identified as potential emerging risks. • Mn concentrations exceeded Australian ecological investigation levels. - Investigating relationships between road age, traffic density and vehicular speed on the concentrations of metals in roadside soils.

  9. Air pollution impacts of speed limitation measures in large cities: The need for improving traffic data in a metropolitan area

    Science.gov (United States)

    Baldasano, José M.; Gonçalves, María; Soret, Albert; Jiménez-Guerrero, Pedro

    2010-08-01

    Assessing the effects of air quality management strategies in urban areas is a major concern worldwide because of the large impacts on health caused by the exposure to air pollution. In this sense, this work analyses the changes in urban air quality due to the introduction of a maximum speed limit to 80 km h -1 on motorways in a large city by using a novel methodology combining traffic assimilation data and modelling systems implemented in a supercomputing facility. Albeit the methodology has been non-specifically developed and can be extrapolated to any large city or megacity, the case study of Barcelona is presented here. Hourly simulations take into account the entire year 2008 (when the 80 km h -1 limit has been introduced) vs. the traffic conditions for the year 2007. The data has been assimilated in an emission model, which considers hourly variable speeds and hourly traffic intensity in the affected area, taken from long-term measurement campaigns for the aforementioned years; it also permits to take into account the traffic congestion effect. Overall, the emissions are reduced up to 4%; however the local effects of this reduction achieve an important impact for the adjacent area to the roadways, reaching 11%. In this sense, the speed limitation effects assessed represent enhancements in air quality levels (5-7%) of primary pollutants over the area, directly improving the welfare of 1.35 million inhabitants (over 41% of the population of the Metropolitan Area) and affecting 3.29 million dwellers who are potentially benefited from this strategy for air quality management (reducing 0.6% the mortality rates in the area).

  10. Speed and path control for conflict-free flight in high air traffic demand in terminal airspace

    Science.gov (United States)

    Rezaei, Ali

    To accommodate the growing air traffic demand, flights will need to be planned and navigated with a much higher level of precision than today's aircraft flight path. The Next Generation Air Transportation System (NextGen) stands to benefit significantly in safety and efficiency from such movement of aircraft along precisely defined paths. Air Traffic Operations (ATO) relying on such precision--the Precision Air Traffic Operations or PATO--are the foundation of high throughput capacity envisioned for the future airports. In PATO, the preferred method is to manage the air traffic by assigning a speed profile to each aircraft in a given fleet in a given airspace (in practice known as (speed control). In this research, an algorithm has been developed, set in the context of a Hybrid Control System (HCS) model, that determines whether a speed control solution exists for a given fleet of aircraft in a given airspace and if so, computes this solution as a collective speed profile that assures separation if executed without deviation. Uncertainties such as weather are not considered but the algorithm can be modified to include uncertainties. The algorithm first computes all feasible sequences (i.e., all sequences that allow the given fleet of aircraft to reach destinations without violating the FAA's separation requirement) by looking at all pairs of aircraft. Then, the most likely sequence is determined and the speed control solution is constructed by a backward trajectory generation, starting with the aircraft last out and proceeds to the first out. This computation can be done for different sequences in parallel which helps to reduce the computation time. If such a solution does not exist, then the algorithm calculates a minimal path modification (known as path control) that will allow separation-compliance speed control. We will also prove that the algorithm will modify the path without creating a new separation violation. The new path will be generated by adding new

  11. Deep Bidirectional and Unidirectional LSTM Recurrent Neural Network for Network-wide Traffic Speed Prediction

    OpenAIRE

    Cui, Zhiyong; Ke, Ruimin; Wang, Yinhai

    2018-01-01

    Short-term traffic forecasting based on deep learning methods, especially long short-term memory (LSTM) neural networks, has received much attention in recent years. However, the potential of deep learning methods in traffic forecasting has not yet fully been exploited in terms of the depth of the model architecture, the spatial scale of the prediction area, and the predictive power of spatial-temporal data. In this paper, a deep stacked bidirectional and unidirectional LSTM (SBU- LSTM) neura...

  12. Motivations for speeding : additional data analysis : traffic tech : technology transfer series.

    Science.gov (United States)

    2016-03-01

    NHTSAs naturalistic driving study, Motivations for Speeding (Richard et al., 2013), examined motivations and situations conducive to speeding behavior. The study collected data from 88 drivers in Seattle, Washington, and 76 drivers in College Stat...

  13. Assess the feasibility of the high-speed railway construction in China by measuring the traffic demand elastic

    Science.gov (United States)

    Yu, Nan; Cao, Yu

    2017-05-01

    The traffic demand elastic is proposed as a new indicator in this study to measure the feasibility of the high-speed railway construction in a more intuitive way. The Matrix Completion (MC) and Semi-Supervised Support Vector Machine (S3VM) are used to realize the measurement and prediction of this index on the basis of the satisfaction investigation on the 326 inter-city railways in china. It is demonstrated that instead of calculating the economic benefits brought by the construction of high-speed railway, this indicator can find the most urgent railways to be improved by directly evaluate the existing railway facilities from the perspective of transportation service improvement requirements.

  14. Design mechanic generator under speed bumper to support electricity recourse for urban traffic light

    Science.gov (United States)

    Sabri, M.; Lauzuardy, Jason; Syam, Bustami

    2018-03-01

    The electrical energy needs for the traffic lights in some cities of developing countries cannot be achieved continuously due to limited capacity and interruption of electricity distribution, the main power plant. This issues can lead to congestion at the crossroads. To overcome the problem of street chaos due to power failure, we can cultivate to provide electrical energy from other sources such as using the bumper to generate kinetic energy, which can be converted into electrical energy. This study designed a generator mechanic that will be mounted on the bumper construction to generate electricity for the purposes of traffic lights at the crossroads. The Mechanical generator is composed of springs, levers, sprockets, chains, flywheel and customize power generator. Through the rotation of the flywheel, we can earned 9 Volt DC voltage and electrical current of 5.89 Ampere. This achievement can be used to charge the accumulator which can be used to power the traffic lights, and to charge the accumulator capacity of 6 Ah, the generator works in the charging time for 1.01 hours.

  15. Impacts of Bus-stops on the Speed of Motorized Vehicles under Heterogeneous Traffic Conditions: A Case-Study of Delhi, India

    Directory of Open Access Journals (Sweden)

    Prateek Bansal

    2014-06-01

    Full Text Available The presence of friction generators1 such as bus-stops, intersections, petrol pumps and pedestrian crossings, etc. significantly influences the speed of traffic stream. Among all the friction generators, understanding the impact of bus-stops is particularly important from planning and modeling perspective in the Indian context. Therefore, this study presents a methodology to quantify the impact of bus-stops on the speed of other motorized vehicles (the total motorized vehicle fleet minus the buses under heterogeneous traffic conditions. The methodology was validated on the typical urban arterials in Delhi, India. Two types of data, location of bus-stops and speed profiles of motorized vehicles, were collected by GPS and V-box respectively. These two data sets were mapped and merged using ArcGIS. To understand the nature of traffic stream near bus-stops, ‘influence regions’ of bus-stops were extracted. Later, characteristic parameters such as lengths of the influence regions and average speeds in the influence regions were computed. Finally, 95% confidence intervals of these characteristic parameters were obtained and regression analysis was performed to quantify the impact of bus-stops on the speed of motorized vehicles. The results of study suggest that the influence region of bus-stops on the corridors investigated varies from 140–170 meters and average speed of motorized vehicles in the influence region is reduced by 26–38% of the free flow speed. These findings can better inform planners about the speeds used in traffic flow and travel demand modeling under heterogeneous conditions by helping them in accounting for the speed-reducing impacts of bus-stops. Moreover, transit planners may also consider the magnitudes and characteristics of the influence regions of bus-stops while determining their locations along the corridor to minimize their adverse impacts on the speed of other motorized vehicles.

  16. Speed

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Speed. The rate of information transferred per second is the speed of the information. Measured in bits per second. Need for speed on the net: You-Tube phenomenon; IPTV; 3D Video telephony. Online gaming; HDTV.

  17. Speed choice and mental workload of elderly cyclists on e-bikes in simple and complex traffic situations : a field experiment.

    NARCIS (Netherlands)

    Vlakveld, W.P. Twisk, D.A.M. Christoph, M.W.T. Boele, M.J. Sikkema, R. Remy, R. & Schwab, A.L.

    2014-01-01

    To study the speed choice and mental workload of elderly cyclists on electrical assisted bicycles (e-bikes) in simple and complex traffic situations compared to these on conventional bicycles, a field experiment was conducted using two instrumented bicycles. These bicycles were identical except for

  18. Reducing travel delay by in-car advice on speed, headway and lane use based on downstream traffic flow conditions - a simulation study

    NARCIS (Netherlands)

    Schakel, W.J.; Klunder, G.; van Arem, B.; Harmsen, E.; Hagenzieker, M.P.

    2012-01-01

    A new advisory ADAS system is implemented in micro simulation to asses the effects on traffic flow as well as on safety. The system uses loop detector data from which situations may be recognized where advices are given to drivers in-car. Advice is given on speed, headway and lane use. Effectively

  19. Quantitative health impact assessment of transport policies: two simulations related to speed limit reduction and traffic re-allocation in the Netherlands.

    Science.gov (United States)

    Schram-Bijkerk, D; van Kempen, E; Knol, A B; Kruize, H; Staatsen, B; van Kamp, I

    2009-10-01

    Few quantitative health impact assessments (HIAs) of transport policies have been published so far and there is a lack of a common methodology for such assessments. To evaluate the usability of existing HIA methodology to quantify health effects of transport policies at the local level. Health impact of two simulated but realistic transport interventions - speed limit reduction and traffic re-allocation - was quantified by selecting traffic-related exposures and health endpoints, modelling of population exposure, selecting exposure-effect relations and estimating the number of local traffic-related cases and disease burden, expressed in disability-adjusted life-years (DALYs), before and after the intervention. Exposure information was difficult to retrieve because of the local scale of the interventions, and exposure-effect relations for subgroups and combined effects were missing. Given uncertainty in the outcomes originating from this kind of missing information, simulated changes in population health by two local traffic interventions were estimated to be small (<5%), except for the estimated reduction in DALYs by less traffic accidents (60%) due to speed limit reduction. Quantitative HIA of transport policies at a local scale is possible, provided that data on exposures, the exposed population and their baseline health status are available. The interpretation of the HIA information should be carried out in the context of the quality of input data and assumptions and uncertainties of the analysis.

  20. Automated mixed traffic vehicle design AMTV 2

    Science.gov (United States)

    Johnston, A. R.; Marks, R. A.; Cassell, P. L.

    1982-01-01

    The design of an improved and enclosed Automated Mixed Traffic Transit (AMTT) vehicle is described. AMTT is an innovative concept for low-speed tram-type transit in which suitable vehicles are equipped with sensors and controls to permit them to operate in an automated mode on existing road or walkway surfaces. The vehicle chassis and body design are presented in terms of sketches and photographs. The functional design of the sensing and control system is presented, and modifications which could be made to the baseline design for improved performance, in particular to incorporate a 20-mph capability, are also discussed. The vehicle system is described at the block-diagram-level of detail. Specifications and parameter values are given where available.

  1. Speed limits in The Netherlands : a detailed consideration of the situation inside and outside built-up areas. Contribution to the International OECD symposium "The Effects of Speed Limits on Traffic Accidents and Transport Energy Use", Dublin, 6-8 October, 1981.

    NARCIS (Netherlands)

    Wegman, F.C.M.

    1981-01-01

    This paper is a contribution to the international OECD symposium "the effect of speed limits on traffic accidents and transport energy use", held in Dublin on 6-8 October 1981. Outlined are the problems of actual speeds, how speed is influenced, speed restrictions etc. in the Netherlands. In

  2. The cooperative University of Iowa / Iowa State University MPH program.

    Science.gov (United States)

    Bickett-Weddle, Danelle A; Aquilino, Mary L; Roth, James A

    2008-01-01

    Public health is an important component of veterinary medicine. In the last 10 years, there has been growing recognition of the need to increase the number of veterinarians trained in public health. The Center for Food Security and Public Health (CFSPH) at Iowa State University (ISU), College of Veterinary Medicine, received a grant from the Centers for Disease Control and Prevention (CDC) to support veterinarians working at CFSPH while pursuing the Master of Public Health degree. CFSPH and ISU administrators worked with the University of Iowa (UI) College of Public Health to establish three cooperative programs for veterinarians to earn the MPH degree. This article describes how these programs were developed and how they operate. (1) Between 2002 and 2005, CFSPH used funds provided by the CDC to support 15 veterinarians as they worked for CFSPH and toward the MPH degree. As the program grew, distance-education methods such as the Internet, Polycom videoconferencing, and the Iowa Communications Network (ICN) were incorporated. (2) A concurrent DVM/MPH degree is now offered; students can complete both degrees in four years. As of January 2008, three students have received their DVM and MPH degrees and 16 students are enrolled in the program. (3) In June 2007, the UI and ISU launched a distance MPH program for veterinarians working in private practice, industry, and government. Eight veterinarians are participating in the program, which includes two two-week, in-person summer sessions, with the remainder of the coursework taken at a distance via the Internet.

  3. Immense changes in traffic - Considerable stability in discourses. Road speed in Danish parliamentary documents 1900-2010

    DEFF Research Database (Denmark)

    Siren, Anu Kristiina; Sørensen, Claus Hedegaard

    2015-01-01

    : speed, individual rights and responsibilities; speed and safety; speed, policy measures, and law enforcement; and speed and other societal goals. While the transport system has undergone a massive change during the last 100 years, we found a considerable stability in the discourses regarding speed...

  4. Queueing and traffic

    NARCIS (Netherlands)

    Baër, Niek

    2015-01-01

    Traffic jams are everywhere, some are caused by constructions or accidents but a large portion occurs naturally. These "natural" traffic jams are a result of variable driving speeds combined with a high number of vehicles. To prevent these traffic jams, we must understand traffic in general, and to

  5. Advisory speed limits : should they be expanded or not? Contribution XVth International Study Week Traffic Engineering and safety: Traffic engineering & the Driver, Theme 2: Speed limits and the driver, Venice, 23-28 September 1985.

    NARCIS (Netherlands)

    Wegman, F.C.M.

    1985-01-01

    Advisory speed limits are meant to be used intermittently in situations which are recognised by the road user, while at the same time, not giving a clear suggestion as to the speed which should be sustained. At present advisory speed limits are almost exclusively applied in narrow road curves.

  6. An estimation of vehicle kilometer traveled and on-road emissions using the traffic volume and travel speed on road links in Incheon City.

    Science.gov (United States)

    Jung, Sungwoon; Kim, Jounghwa; Kim, Jeongsoo; Hong, Dahee; Park, Dongjoo

    2017-04-01

    The objective of this study is to estimate the vehicle kilometer traveled (VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors, large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea. Copyright © 2016. Published by Elsevier B.V.

  7. Outflow of traffic from the national capital Kuala Lumpur to the north, south and east coast highways using flow, speed and density relationships

    Institute of Scientific and Technical Information of China (English)

    Nik Hashim Nik Mustapha; Nik Nur Wahidah Nik Hashim

    2016-01-01

    The functional relationships between flow (veh/km), density (veh/h) and speed (km/h) in traffic congestion have a long history of research. However, their findings and techniques persist to be relevant to this day. The analysis is pertinent, particularly in finding the best fit for the three major highways in Malaysia, namely the KL-Karak Highway, KL-Seremban Highway and KL-Ipoh Highway. The trans-logarithm function of density—speed model was compared to the classical models of Greenshields, Greenberg, Underwood and Drake et al. using data provided by the Transport Statistics Malaysia 2014. The results of regression analysis revealed that the Greenshields and Greenberg models were statistically signifi-cant. The trans-logarithm function was also tested and the results were nonetheless without exception. Its usefulness in addition to statistical significance related to the derived economic concepts of maximum speed and the related number of vehicles, flow and density and the limits of free speed were relevant in comparing the individual levels of traffic congestion between highways. For instance, KL-Karak Highway was least congested compared to KL-Seremban Highway and KL-Ipoh Highway. Their maximum speeds, based on three lanes carriage capacity of one direction, were 33.4 km/h for KL-Karak, 15.9 km/h for KL-Seremban, and 21.1 km/h for KL-Ipoh. Their corresponding flows were approxi-mated at 1080.9 veh/h, 1555.4 veh/h, and 1436.6 veh/h.

  8. Outflow of traffic from the national capital Kuala Lumpur to the north, south and east coast highways using flow, speed and density relationships

    Directory of Open Access Journals (Sweden)

    Nik Hashim Nik Mustapha

    2016-12-01

    Full Text Available The functional relationships between flow (veh/km, density (veh/h and speed (km/h in traffic congestion have a long history of research. However, their findings and techniques persist to be relevant to this day. The analysis is pertinent, particularly in finding the best fit for the three major highways in Malaysia, namely the KL-Karak Highway, KL-Seremban Highway and KL-Ipoh Highway. The trans-logarithm function of density–speed model was compared to the classical models of Greenshields, Greenberg, Underwood and Drake et al. using data provided by the Transport Statistics Malaysia 2014. The results of regression analysis revealed that the Greenshields and Greenberg models were statistically significant. The trans-logarithm function was also tested and the results were nonetheless without exception. Its usefulness in addition to statistical significance related to the derived economic concepts of maximum speed and the related number of vehicles, flow and density and the limits of free speed were relevant in comparing the individual levels of traffic congestion between highways. For instance, KL-Karak Highway was least congested compared to KL-Seremban Highway and KL-Ipoh Highway. Their maximum speeds, based on three lanes carriage capacity of one direction, were 33.4 km/h for KL-Karak, 15.9 km/h for KL-Seremban, and 21.1 km/h for KL-Ipoh. Their corresponding flows were approximated at 1080.9 veh/h, 1555.4 veh/h, and 1436.6 veh/h.

  9. Vehicle-based road dust emission measurement (III):. effect of speed, traffic volume, location, and season on PM 10 road dust emissions in the Treasure Valley, ID

    Science.gov (United States)

    Etyemezian, V.; Kuhns, H.; Gillies, J.; Chow, J.; Hendrickson, K.; McGown, M.; Pitchford, M.

    The testing re-entrained aerosol kinetic emissions from roads (TRAKER) road dust measurement system was used to survey more than 400 km of paved roads in southwestern Idaho during 3-week sampling campaigns in winter and summer, 2001. Each data point, consisting of a 1-s measurement of particle light scattering sampled behind the front tire, was associated with a link (section of road) in the traffic demand model network for the Treasure Valley, ID. Each link was in turn associated with a number of characteristics including posted speed limit, vehicle kilometers traveled (vkt), road class (local/residential, collector, arterial, and interstate), county, and land use (urban vs. rural). Overall, the TRAKER-based emission factors based on location, setting, season, and speed spanned a narrow range from 3.6 to 8.0 g/vkt. Emission factors were higher in winter compared to summer, higher in urban areas compared to rural, and lower for roads with fast travel speeds compared to slower roads. The inherent covariance between traffic volume and traffic speed obscured the assessment of the effect of traffic volume on emission potentials. Distance-based emission factors expressed in grams per kilometer traveled (g/vkt) for roads with low travel speeds (˜11 m/s residential roads) compared to those with high travel speeds (˜25 m/s interstates) were higher (5.2 vs. 3.0 g/vkt in summer and 5.9 vs. 4.9 g/vkt in winter). However, emission potentials which characterize the amount of suspendable material on a road were substantially higher on roads with low travel speeds (0.71 vs. 0.13 g/vkt/(m/s) in summer and 0.78 vs. 0.21 g/vkt/(m/s) in winter). This suggested that while high speed roads are much cleaner (factor of 5.4 in summer), on a vehicle kilometer traveled basis, emissions from high and low speed roads are of the same order. Emission inventories based on the TRAKER method, silt loadings obtained during the field study, and US EPA's AP-42 default values of silt loading were

  10. The role of gender in MPH graduates' salaries.

    Science.gov (United States)

    Bradley, E H; White, W; Anderson, E; Mattocks, K; Pistell, A

    2000-01-01

    Several studies have demonstrated that workforce roles and salaries differ substantially between men and women in administrative positions within the health care industry. Recent studies of graduates with masters of business administration (MBA) and masters of health administration (MHA) degrees have indicated that women tend to experience lower salaries, given like responsibilities. However, the impact of gender on salary has been less studied among masters of public health (MPH) graduates in the health care field. Our objective was to assess the impact of gender on salary among MPH degree graduates. Using a cross-sectional survey of all graduates from the MPH program at Yale University between 1991-1997 (n = 201, response rate = 51%), we ascertained graduates' reported salary in the first job post-graduation and reported salary in their current position. Bivariate and multivariate analyses were used to assess the unadjusted and adjusted associations between gender and salary. Salaries in both the first job post-graduation and in the current job differed significantly by gender, with women earning less than men (p-values salary gap widened as the years since graduation increased, although the sample size did not allow comprehensive testing of this trend.

  11. A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles.

    Science.gov (United States)

    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.

  12. Speeds in school zones.

    Science.gov (United States)

    2009-02-01

    School speed zones are frequently requested traffic controls for school areas, based on the common belief : that if the transportation agency would only install a reduced speed limit, then drivers would no longer : speed through the area. This resear...

  13. Efficient disk-to-disk copy through long-distance high-speed networks with background traffic

    International Nuclear Information System (INIS)

    Tanida, Naoki; Hiraki, Kei; Inaba, Mary

    2010-01-01

    We propose 'ICDC - InterContinental Disk Copy', a data sharing facility between distant places. ICDC aims to transfer huge amount of data files easily on Long Fat-pipe Networks with some background traffic. ICDC consists of commodity PCs and Solid State Drives and we apply Inter Packet Gap tuning technique to it. Using 'ICDC-1 Gbps model', we transferred data between Tokyo and Cadarache via New York. We attained about 860 Mbps, i.e., 86% usage of the network bottleneck bandwidth.

  14. Inficon Transpector MPH Mass Spectrometer Random Vibration Test Report

    Science.gov (United States)

    Santiago-Bond, Jo; Captain, Janine

    2015-01-01

    The purpose of this test report is to summarize results from the vibration testing of the INFICON Transpector MPH100M model Mass Spectrometer. It also identifies requirements satisfied, and procedures used in the test. As a payload of Resource Prospector, it is necessary to determine the survivability of the mass spectrometer to proto-qualification level random vibration. Changes in sensitivity of the mass spectrometer can be interpreted as a change in alignment of the instrument. The results of this test will be used to determine any necessary design changes as the team moves forward with flight design.

  15. Snowboard, wakeboard, dashboard? Isolated fracture of the lateral process of the talus in a high-speed road traffic accident.

    LENUS (Irish Health Repository)

    Ng, Evangeline Shimei

    2013-01-01

    We present a 23-year-old man who sustained an isolated fracture of the lateral process of the talus (LPT) in a head-on vehicle collision at a combined speed of 200 km\\/h. The driver of the other vehicle sustained fatal injuries at the scene. The LPT was openly reduced and fixed with successful outcome at 3 months. This case is unusual in the method of injury, in particular in relation to the isolated relatively minor injury sustained.

  16. Effects of vehicle power on passenger vehicle speeds.

    Science.gov (United States)

    McCartt, Anne T; Hu, Wen

    2017-07-04

    During the past 2 decades, there have been large increases in mean horsepower and the mean horsepower-to-vehicle weight ratio for all types of new passenger vehicles in the United States. This study examined the relationship between travel speeds and vehicle power, defined as horsepower per 100 pounds of vehicle weight. Speed cameras measured travel speeds and photographed license plates and drivers of passenger vehicles traveling on roadways in Northern Virginia during daytime off-peak hours in spring 2013. The driver licensing agencies in the District of Columbia, Maryland, and Virginia provided vehicle information numbers (VINs) by matching license plate numbers with vehicle registration records and provided the age, gender, and ZIP code of the registered owner(s). VINs were decoded to obtain the curb weight and horsepower of vehicles. The study focused on 26,659 observed vehicles for which information on horsepower was available and the observed age and gender of drivers matched vehicle registration records. Log-linear regression estimated the effects of vehicle power on mean travel speeds, and logistic regression estimated the effects of vehicle power on the likelihood of a vehicle traveling over the speed limit and more than 10 mph over the limit. After controlling for driver characteristics, speed limit, vehicle type, and traffic volume, a 1-unit increase in vehicle power was associated with a 0.7% increase in mean speed, a 2.7% increase in the likelihood of a vehicle exceeding the speed limit by any amount, and an 11.6% increase in the likelihood of a vehicle exceeding the limit by 10 mph. All of these increases were highly significant. Speeding persists as a major factor in crashes in the United States. There are indications that travel speeds have increased in recent years. The current findings suggest the trend toward substantially more powerful vehicles may be contributing to higher speeds. Given the strong association between travel speed and crash

  17. Materials at 200 mph: Making NASCAR Faster and Safer

    Science.gov (United States)

    Leslie-Pelecky, Diandra

    2008-03-01

    You cannot win a NASCAR race without understanding science.ootnotetextDiandra Leslie-Pelecky, The Physics of NASCAR (Dutton, New York City, 2008). Materials play important roles in improving performance, as well as ensuring safety. On the performance side, NASCAR limits the materials race car scientists and engineers can use to limit ownership costs. `Exotic metals' are not allowed, so controlling microstructure and nanostructure are important tools. Compacted Graphite Iron, a cast iron in which magnesium additions produce interlocking microscale graphite reinforcements, makes engine blocks stronger and lighter. NASCAR's new car design employs a composite called Tegris^TM that has 70 percent of the strength of carbon fiber composites at about 10 percent of the cost. The most important role of materials in racing is safety. Drivers wear firesuits made of polymers that carbonize (providing thermal protection) and expand (reducing oxygen access) when heated. Catalytic materials originally developed for space-based CO2 lasers filter air for drivers during races. Although materials help cars go fast, they also help cars slow down safely---important because the kinetic energy of a race car going 180 mph is nine times greater than that of a passenger car going 60 mph. Energy-absorbing foams in the cars and on the tracks control energy dissipation during accidents. To say that most NASCAR fans (and there are estimated to be 75 million of them) are passionate about their sport is an understatement. NASCAR fans understand that science and engineering are integral to keeping their drivers safe and helping their teams win. Their passion for racing gives us a great opportunity to share our passion for science with them. NASCAR^ is a registered trademark of the National Association for Stock Car Auto Racing, Inc. Tegris^TM is a trademark of Milliken & Company.

  18. Strain monitoring of a newly developed precast concrete track for high speed railway traffic using embedded fiber optic sensors

    Science.gov (United States)

    Crail, Stephanie; Reichel, D.; Schreiner, U.; Lindner, E.; Habel, Wolfgang R.; Hofmann, Detlef; Basedau, Frank; Brandes, K.; Barner, A.; Ecke, Wolfgang; Schroeder, Kerstin

    2002-07-01

    In a German slab track system (Feste Fahrbahn FF, system Boegl) for speeds up to 300 km/h and more different fiber optic sensors have been embedded in several levels and locations of the track system. The track system consists of prestressed precast panels of steel fiber concrete which are supported by a cat-in-situ concrete or asphalt base course. The sensors are to measure the bond behavior or the stress transfer in the track system. For that, tiny fiber-optic sensors - fiber Fabry-Perot and Bragg grating sensors - have been embedded very near to the interface of the layers. Measurements were taken on a full scale test sample (slab track panel of 6.45 m length) as well as on a real high speed track. The paper describes the measurement task and discusses aspects with regard to sensor design and prefabrication of the sensor frames as well as the embedding procedure into the concrete track. Results from static and dynamic full scale tests carried out in the testing laboratory of BAM and from measurements on a track are given.

  19. A health impact assessment of a proposed bill to decrease speed limits on local roads in Massachusetts (U.S.A.).

    Science.gov (United States)

    James, Peter; Ito, Kate; Banay, Rachel F; Buonocore, Jonathan J; Wood, Benjamin; Arcaya, Mariana C

    2014-10-02

    Decreasing traffic speeds increases the amount of time drivers have to react to road hazards, potentially averting collisions, and makes crashes that do happen less severe. Boston's regional planning agency, the Metropolitan Area Planning Council (MAPC), in partnership with the Massachusetts Department of Public Health (MDPH), conducted a Health Impact Assessment (HIA) that examined the potential health impacts of a proposed bill in the state legislature to lower the default speed limits on local roads from 30 miles per hour (mph) to 25 mph. The aim was to reduce vehicle speeds on local roads to a limit that is safer for pedestrians, cyclists, and children. The passage of this proposed legislation could have had far-reaching and potentially important public health impacts. Lower default speed limits may prevent around 18 fatalities and 1200 serious injuries to motorists, cyclists and pedestrians each year, as well as promote active transportation by making local roads feel more hospitable to cyclists and pedestrians. While a lower speed limit would increase congestion and slightly worsen air quality, the benefits outweigh the costs from both a health and economic perspective and would save the state approximately $62 million annually from prevented fatalities and injuries.

  20. Mte1 interacts with Mph1 and promotes crossover recombination and telomere maintenance

    DEFF Research Database (Denmark)

    Pinela da Silva, Sonia Cristina; Altmannova, Veronika; Luke-Glaser, Sarah

    2016-01-01

    Mph1 is a member of the conserved FANCM family of DNA motor proteins that play key roles in genome maintenance processes underlying Fanconi anemia, a cancer predisposition syndrome in humans. Here, we identify Mte1 as a novel interactor of the Mph1 helicase in Saccharomyces cerevisiae. In vitro...

  1. Treatment-Continuity of ADHD Compared Using Immediate-Release and Extended-Release MPH

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-07-01

    Full Text Available The continuity of methylphenidate (MPH therapy for ADHD in young Medicaid beneficiaries (ages 6 to 17 years treated with immediate-release (IR or extended-release (ER MPH formulations was compared in an analysis of statewide California Medicaid claims (2000-2003 conducted at Columbia University, New York; University of Pennsylvania, Philadelphia; and McNeil Pharmaceuticals, Fort Washington, PA.

  2. MPH program adaptability in a competitive marketplace: the case for continued assessment.

    Science.gov (United States)

    Caron, Rosemary M; Tutko, Holly

    2010-06-01

    In the last several years, the number of Master of Public Health (MPH) programs has increased rapidly in the US. As such, MPH programs, particularly smaller-sized ones, need to critically examine how their programs are meeting the needs and preferences of local public health practitioners. To assist in this necessity, the University of New Hampshire conducted a comprehensive educational assessment of its effectiveness as a smaller-sized, accredited MPH program. The aim of the assessment was to review the MPH program from the perspective of all stakeholders and then to agree on changes that would contribute to the fulfillment of the program's mission, as well as improve program quality and reach. The program's stakeholders examined the following components: policy development and implementation; target audience; marketing strategies; marketplace position; delivery model; curriculum design; and continuing education. Though assessment activities explored a wide array of program attributes, target audience, curriculum design, and delivery strategy presented significant challenges and opportunities for our smaller MPH Program to remain competitive. The effort put forth into conducting an in-depth assessment of the core components of our program also allowed for a comparison to the increasing number of MPH programs developing regionally. Since public health practice is changing and the education of public health practitioners must be adaptable, we propose that a routine assessment of an institution's MPH program could not only meet this need but also assist with keeping smaller, unbranded MPH programs competitive in a burgeoning marketplace.

  3. Evaluation and reformulation of the maximum peak height algorithm (MPH) and application in a hypertrophic lagoon

    Science.gov (United States)

    Pitarch, Jaime; Ruiz-Verdú, Antonio; Sendra, María. D.; Santoleri, Rosalia

    2017-02-01

    We studied the performance of the MERIS maximum peak height (MPH) algorithm in the retrieval of chlorophyll-a concentration (CHL), using a matchup data set of Bottom-of-Rayleigh Reflectances (BRR) and CHL from a hypertrophic lake (Albufera de Valencia). The MPH algorithm produced a slight underestimation of CHL in the pixels classified as cyanobacteria (83% of the total) and a strong overestimation in those classified as eukaryotic phytoplankton (17%). In situ biomass data showed that the binary classification of MPH was not appropriate for mixed phytoplankton populations, producing also unrealistic discontinuities in the CHL maps. We recalibrated MPH using our matchup data set and found that a single calibration curve of third degree fitted equally well to all matchups regardless of how they were classified. As a modification to the former approach, we incorporated the Phycocyanin Index (PCI) in the formula, thus taking into account the gradient of phytoplankton composition, which reduced the CHL retrieval errors. By using in situ biomass data, we also proved that PCI was indeed an indicator of cyanobacterial dominance. We applied our recalibration of the MPH algorithm to the whole MERIS data set (2002-2012). Results highlight the usefulness of the MPH algorithm as a tool to monitor eutrophication. The relevance of this fact is higher since MPH does not require a complete atmospheric correction, which often fails over such waters. An adequate flagging or correction of sun glint is advisable though, since the MPH algorithm was sensitive to sun glint.

  4. Traffic Offences: Planned or Habitual? Using the Theory of Planned Behaviour and habit strength to explain frequency and magnitude of speeding and driving under the influence of alcohol.

    Science.gov (United States)

    Lheureux, Florent; Auzoult, Laurent; Charlois, Colette; Hardy-Massard, Sandrine; Minary, Jean-Pierre

    2016-02-01

    This study addresses the socio-cognitive determinants of traffic offences, in particular of speeding and drinking and driving. It has two aims: (1) to test the hypothesis of a direct effect of habits on offences (i.e., independent of intentions) by employing a specific measure of habits (i.e., the SRIH) and (2) to analyse the offences by taking account of three distinct parameters: Frequency, usual magnitude (i.e., the most frequent deviation from the law) and maximal magnitude (i.e., the greatest deviation occasionally adopted) in order to represent more accurately the variability of the offending behaviours. A total of 642 drivers replied to a questionnaire. The results corroborate the idea that intention and habit are distinct and direct determinants of offences. The use of the SRIH dismisses the criticisms made with regard to the measure of past behaviour. The distinction between the three behavioural parameters proves to be relevant, as their determinants are not exactly similar. Finally, attitude and subjective norm had direct effects on the maximal magnitude and/or on the frequency of the offence. The discussion concerns the contribution of this study to the analysis of offences as well as its limitations and addresses the theoretical plausibility of the direct effects of attitude and the subjective norm. © 2015 The British Psychological Society.

  5. Traffic theory

    National Research Council Canada - National Science Library

    Gazis, Denos C

    2002-01-01

    ... of traffic signal settings The vehicle-actuated traffic signal 87 89 77 CHAPTER 3. TRAFFIC CONTROL 101 Objectives of Traffic Control 103 Single, Isolated Intersection 105 Synchronization Scheme...

  6. Speeding the traffic on grids

    CERN Multimedia

    Port, O

    2002-01-01

    CERN is one of a number of organizations looking at ways to to accelerate grid computing. CERN researcher Wolfgang Hoschek said new software will soon scan all the available computers on the Web and find the most efficient combination to solve a particular problem (1/3 page).

  7. Speed Variance and Its Influence on Accidents.

    Science.gov (United States)

    Garber, Nicholas J.; Gadirau, Ravi

    A study was conducted to investigate the traffic engineering factors that influence speed variance and to determine to what extent speed variance affects accident rates. Detailed analyses were carried out to relate speed variance with posted speed limit, design speeds, and other traffic variables. The major factor identified was the difference…

  8. Design and Development of an MPH Program for Distance Education Delivery

    OpenAIRE

    Steven R. Hawks

    2008-01-01

    The Master-s of Public Health (MPH) degree is growing in popularity among a number of higher education institutions throughout the world as a distance education graduate program. This paper offers an overview of program design and development strategies that promote successful distance delivery of MPH programs. Design and development challenges are discussed in terms of type of distance delivery, accreditation, student demand, faculty development, user needs, course conte...

  9. Traffic flow models and impact of combined lane change and speed limit control on environment in case of high truck traffic volumes. A Research Report from the National Center for Sustainable Transportation.

    NARCIS (Netherlands)

    Ioannou, P. Zhang, Y. & Zhao, Y.

    2017-01-01

    This report presents the work performed in collaboration with University of California, Riverside (UCR) as part of a project to University of California, Davis funded by the California Energy Commission (CEC). The aim of the project is to research intelligent traffic control strategies, which will

  10. Traffic safety strategies

    Directory of Open Access Journals (Sweden)

    V. Sadauskas

    2003-04-01

    Full Text Available Fast development of the number of vehicles is closely related not only to large benefit for the public but also to certain undesirable social and economic consequences. Firstly - large numbers of injured and killed people are involved into the accidents. The target to improve traffic safety situation in Lithuania can be reached only after the detailed evaluation of transport system, environment, traffic participants, road and vehicle. Taking into consideration the accident situation in Lithuania and its causes the followings priority trends are suggested: The improvement of the coordination of road traffic safety system, the training and education of road users, the explanation of the importance of traffic safety and its propagation, the improvement of traffic conditions. Recommendations and proposals for differentiated criterion of maximum speed limit selection taking into account different factors are provided in the work.

  11. Making the Traffic Operations Case for Congestion Pricing: Operational Impacts of Congestion Pricing

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Shih-Miao [ORNL; Hu, Patricia S [ORNL; Davidson, Diane [ORNL

    2011-02-01

    Congestion begins when an excess of vehicles on a segment of roadway at a given time, resulting in speeds that are significantly slower than normal or 'free flow' speeds. Congestion often means stop-and-go traffic. The transition occurs when vehicle density (the number of vehicles per mile in a lane) exceeds a critical level. Once traffic enters a state of congestion, recovery or time to return to a free-flow state is lengthy; and during the recovery process, delay continues to accumulate. The breakdown in speed and flow greatly impedes the efficient operation of the freeway system, resulting in economic, mobility, environmental and safety problems. Freeways are designed to function as access-controlled highways characterized by uninterrupted traffic flow so references to freeway performance relate primarily to the quality of traffic flow or traffic conditions as experienced by users of the freeway. The maximum flow or capacity of a freeway segment is reached while traffic is moving freely. As a result, freeways are most productive when they carry capacity flows at 60 mph, whereas lower speeds impose freeway delay, resulting in bottlenecks. Bottlenecks may be caused by physical disruptions, such as a reduced number of lanes, a change in grade, or an on-ramp with a short merge lane. This type of bottleneck occurs on a predictable or 'recurrent' basis at the same time of day and same day of week. Recurrent congestion totals 45% of congestion and is primarily from bottlenecks (40%) as well as inadequate signal timing (5%). Nonrecurring bottlenecks result from crashes, work zone disruptions, adverse weather conditions, and special events that create surges in demand and that account for over 55% of experienced congestion. Figure 1.1 shows that nonrecurring congestion is composed of traffic incidents (25%), severe weather (15%), work zones, (10%), and special events (5%). Between 1995 and 2005, the average percentage change in increased peak traveler

  12. System analysis of automated speed enforcement implementation.

    Science.gov (United States)

    2016-04-01

    Speeding is a major factor in a large proportion of traffic crashes, injuries, and fatalities in the United States. Automated Speed Enforcement (ASE) is one of many approaches shown to be effective in reducing speeding violations and crashes. However...

  13. Synchronized flow in oversaturated city traffic.

    Science.gov (United States)

    Kerner, Boris S; Klenov, Sergey L; Hermanns, Gerhard; Hemmerle, Peter; Rehborn, Hubert; Schreckenberg, Michael

    2013-11-01

    Based on numerical simulations with a stochastic three-phase traffic flow model, we reveal that moving queues (moving jams) in oversaturated city traffic dissolve at some distance upstream of the traffic signal while transforming into synchronized flow. It is found that, as in highway traffic [Kerner, Phys. Rev. E 85, 036110 (2012)], such a jam-absorption effect in city traffic is explained by a strong driver's speed adaptation: Time headways (space gaps) between vehicles increase upstream of a moving queue (moving jam), resulting in moving queue dissolution. It turns out that at given traffic signal parameters, the stronger the speed adaptation effect, the shorter the mean distance between the signal location and the road location at which moving queues dissolve fully and oversaturated traffic consists of synchronized flow only. A comparison of the synchronized flow in city traffic found in this Brief Report with synchronized flow in highway traffic is made.

  14. How lowering speed limits in an urban highway affects traffics performance and emissions: the case of Madrid M-30 ring-road

    OpenAIRE

    Pérez Prada, Fiamma; Monzón de Cáceres, Andrés

    2014-01-01

    The city of Madrid keeps not meeting the GHG and air pollutant limits set by the European legislation. A broad range of strategies have being taken into account to reduce both types of emissions; however traffic management meas ures are usually consigned to the sidelines. In 2004, Madrid City Council launched a plan to re-design its inner ring-road supported by a socioeconomic study that evaluated the environmental and operational benefits of the project. For safety reasons the planned spe...

  15. Review of MPH practicum requirements in accredited schools of public health.

    Science.gov (United States)

    Oglesby, Willie H; Alemagno, Sonia A; Zullo, Melissa D; Hartman, Olivia; Smith, Katalin; Smith, Joseph; Buzzelli, Michael

    2013-06-01

    Accreditation criteria by the Council on Education for Public Health (CEPH) state that prior to graduation, Masters of Public Health (MPH) students must demonstrate the application of knowledge and skills through a practice experience, commonly called the "Practicum." The purpose of this research was to review those MPH Practicum requirements. Practicum guidelines from US-based schools of public health that were accredited as of October 2011 were reviewed. Data on each Practicum's level of coordination, timing, and credit and contact hours as well as information about written agreements, preceptors, and how the Practicum was graded were collected. Seventy-four Practicums in 46 accredited schools of public health were reviewed. The majority (85 %) of accredited schools controlled the Practicum at the school-level. Among the Practicums reviewed, most did not require completion of any credit hours or the MPH core courses (57 and 74 %, respectively) prior to starting the Practicum; 82 % required written agreements; 60 % had stated criteria for the approval of preceptors; and 76 % required students to submit a product for grading at the conclusion of the Practicum. The results of this research demonstrate that the majority of accredited schools of public health designed Practicum requirements that reflect some of the criteria established by CEPH; however, issues related to timing, credit and contact hours, and preceptor qualifications vary considerably. We propose that a national dialogue begin among public health faculty and administrators to address these and other findings to standardize the Practicum experience for MPH students.

  16. Future Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Sorenson, Spencer C.

    1998-01-01

    In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered. An estim......In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered...

  17. Some random models in traffic science

    Energy Technology Data Exchange (ETDEWEB)

    Hjorth, U.

    1996-06-01

    We give an overview of stochastic models for the following traffic phenomena. Models for traffic flow including gaps and capacities for lanes, crossings and roundabouts. Models for wanted and achieved speed distributions. Mode selection models including dispersed equilibrium models and traffic accident models. Also some statistical questions are discussed. 60 refs, 1 tab

  18. A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles

    Science.gov (United States)

    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. Effectiveness of Motorcycle speed controlled by speed hump

    Directory of Open Access Journals (Sweden)

    Pornsiri Urapa

    2014-09-01

    Full Text Available Speed humps are one of the traffic calming measures widely accepted to control vehicle speed in the local road. Humps standards from the western countries are designed mainly for the passenger car. This study, therefore, aims to reveal the effectiveness of speed hump to control the motorcycle speed. This study observes the free-flow speed of the riders at the total of 20 speed bumps and humps. They are 0.3-14.8 meter in width and 5-18 centimeter in height. The results reveal that the 85th percentile speeds reduce 15-65 percent when crossing the speed bumps and speed humps. Besides, this study develops the speed model to predict the motorcycle mean speed and 85th percentile speed. It is found that speed humps follow the ITE standard can control motorcycle crossing speeds to be 25-30 Kph which are suitable to travel on the local road.

  20. Efecto de la disminución de la velocidad vehicular en la durabilidad de una capa asfáltica Effect of reducing traffic speed on the durability of a road asphalt layer

    Directory of Open Access Journals (Sweden)

    Hugo Alexander Rondón Quintana

    2013-04-01

    Full Text Available Actualmente, en América Latina las vías están experimentando un incremento en el nivel de congestionamiento vehicular en sus vías principales, y con ello una consecuente baja velocidad de marcha. En el artículo se presentan los resultados de una fase experimental desarrollada con el fin de evidenciar el cambio que experimentan las propiedades mecánicas bajo carga repetida de una mezcla densa en caliente tipo MDC-2 cuando se disminuye la velocidad de circulación vehicular. El caso de estudio que se reporta es para mezclas que se fabrican y construyen en Bogotá D.C., Colombia. Como conclusión general se obtiene que al reducir los vehículos la velocidad de circulación sobre una vía en servicio, la mezcla de concreto asfáltico disminuye su rigidez y la resistencia a fatiga. Por ejemplo, disminuir la velocidad de 60 km/h a 30 km/h genera una disminución aproximada de 15,6% en la rigidez de la mezcla analizada y 39,7% en su vida a fatiga.Due to increased congestion on its main routes, the cities of Latin American, have been experiencing a reduction in traffic speed. This article presents the results of research conducted to establish the changes of the mechanical properties under repeated loads that occur in a MDC-2 hot mix asphalt (HMA when the vehicular speed decreases. The studies were carried out using asphalt mixtures produced in the city of Bogotá, Colombia. As a general conclusion, it has been found that by reducing the speed of traffic, the asphalt concrete mixture reduces its stiffness and resistance to fatigue. For example, a reduction of the speed from 60 km/h to 30 km/h results in a reduction of approximately 15.6% in the stiffness of the asphalt mixture and 39.5% in its fatigue life.

  1. Adaptive Traffic Signal Control: Deep Reinforcement Learning Algorithm with Experience Replay and Target Network

    OpenAIRE

    Gao, Juntao; Shen, Yulong; Liu, Jia; Ito, Minoru; Shiratori, Norio

    2017-01-01

    Adaptive traffic signal control, which adjusts traffic signal timing according to real-time traffic, has been shown to be an effective method to reduce traffic congestion. Available works on adaptive traffic signal control make responsive traffic signal control decisions based on human-crafted features (e.g. vehicle queue length). However, human-crafted features are abstractions of raw traffic data (e.g., position and speed of vehicles), which ignore some useful traffic information and lead t...

  2. Speed, speed variation and crash relationships for urban arterials.

    Science.gov (United States)

    Wang, Xuesong; Zhou, Qingya; Quddus, Mohammed; Fan, Tianxiang; Fang, Shou'en

    2018-04-01

    Speed and speed variation are closely associated with traffic safety. There is, however, a dearth of research on this subject for the case of urban arterials in general, and in the context of developing nations. In downtown Shanghai, the traffic conditions in each direction are very different by time of day, and speed characteristics during peak hours are also greatly different from those during off-peak hours. Considering that traffic demand changes with time and in different directions, arterials in this study were divided into one-way segments by the direction of flow, and time of day was differentiated and controlled for. In terms of data collection, traditional fixed-based methods have been widely used in previous studies, but they fail to capture the spatio-temporal distributions of speed along a road. A new approach is introduced to estimate speed variation by integrating spatio-temporal speed fluctuation of a single vehicle with speed differences between vehicles using taxi-based high frequency GPS data. With this approach, this paper aims to comprehensively establish a relationship between mean speed, speed variation and traffic crashes for the purpose of formulating effective speed management measures, specifically using an urban dataset. From a total of 234 one-way road segments from eight arterials in Shanghai, mean speed, speed variation, geometric design features, traffic volume, and crash data were collected. Because the safety effects of mean speed and speed variation may vary at different segment lengths, arterials with similar signal spacing density were grouped together. To account for potential correlations among these segments, a hierarchical Poisson log-normal model with random effects was developed. Results show that a 1% increase in mean speed on urban arterials was associated with a 0.7% increase in total crashes, and larger speed variation was also associated with increased crash frequency. Copyright © 2018 Elsevier Ltd. All rights

  3. Traveler oriented traffic performance metrics using real time traffic data from the Midtown-in-Motion (MIM) project in Manhattan, NY.

    Science.gov (United States)

    2013-10-01

    In a congested urban street network the average traffic speed is an inadequate metric for measuring : speed changes that drivers can perceive from changes in traffic control strategies. : A driver oriented metric is needed. Stop frequency distrib...

  4. An auxiliary graph based dynamic traffic grooming algorithm in spatial division multiplexing enabled elastic optical networks with multi-core fibers

    Science.gov (United States)

    Zhao, Yongli; Tian, Rui; Yu, Xiaosong; Zhang, Jiawei; Zhang, Jie

    2017-03-01

    A proper traffic grooming strategy in dynamic optical networks can improve the utilization of bandwidth resources. An auxiliary graph (AG) is designed to solve the traffic grooming problem under a dynamic traffic scenario in spatial division multiplexing enabled elastic optical networks (SDM-EON) with multi-core fibers. Five traffic grooming policies achieved by adjusting the edge weights of an AG are proposed and evaluated through simulation: maximal electrical grooming (MEG), maximal optical grooming (MOG), maximal SDM grooming (MSG), minimize virtual hops (MVH), and minimize physical hops (MPH). Numeric results show that each traffic grooming policy has its own features. Among different traffic grooming policies, an MPH policy can achieve the lowest bandwidth blocking ratio, MEG can save the most transponders, and MSG can obtain the fewest cores for each request.

  5. Road Traffic Accidents in Nigeria: A Public Health Problem

    African Journals Online (AJOL)

    traffic accident as an issue that needs urgent attention aimed at reducing the ... include driver behaviour, visual and auditory acuity, decision making ability and reaction speed. Drug and ... Road traffic accidents have physical, social, emotional.

  6. Traffic classification with passive measurement

    OpenAIRE

    Pham, Hoang Phong

    2005-01-01

    Abstract This is a master thesis from a collaboration between Oslo University College and Uninett Research. Uninett have a passive monitoring device on a 2.5 Gbps backbone link between Trondheim and Narvik. They uses measurement with optical splitters and specialized measuring interfaces to trace traffic with Gigabit speed. We would like to investigate the structure and patterns in these data. It is of special interest to classify the traffic belonging to different services and protocols. ...

  7. Estimating emissions from railway traffic

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, M.W.; Sorenson, C.

    1997-07-01

    The report discusses methods that can be used to estimate the emissions from various kinds of railway traffic. The methods are based on the estimation of the energy consumption of the train, so that comparisons can be made between electric and diesel driven trains. Typical values are given for the necessary traffic parameters, emission factors, and train loading. Detailed models for train energy consumption are presented, as well as empirically based methods using average train speed and distance between stop. (au)

  8. Wind speed perception and risk.

    Directory of Open Access Journals (Sweden)

    Duzgun Agdas

    Full Text Available BACKGROUND: How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. METHOD: We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. RESULTS: Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk. The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. CONCLUSION: These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  9. Wind speed perception and risk.

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D; Masters, Forrest J

    2012-01-01

    How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human-wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual-perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters.

  10. Wind Speed Perception and Risk

    Science.gov (United States)

    Agdas, Duzgun; Webster, Gregory D.; Masters, Forrest J.

    2012-01-01

    Background How accurately do people perceive extreme wind speeds and how does that perception affect the perceived risk? Prior research on human–wind interaction has focused on comfort levels in urban settings or knock-down thresholds. No systematic experimental research has attempted to assess people's ability to estimate extreme wind speeds and perceptions of their associated risks. Method We exposed 76 people to 10, 20, 30, 40, 50, and 60 mph (4.5, 8.9, 13.4, 17.9, 22.3, and 26.8 m/s) winds in randomized orders and asked them to estimate wind speed and the corresponding risk they felt. Results Multilevel modeling showed that people were accurate at lower wind speeds but overestimated wind speeds at higher levels. Wind speed perceptions mediated the direct relationship between actual wind speeds and perceptions of risk (i.e., the greater the perceived wind speed, the greater the perceived risk). The number of tropical cyclones people had experienced moderated the strength of the actual–perceived wind speed relationship; consequently, mediation was stronger for people who had experienced fewer storms. Conclusion These findings provide a clearer understanding of wind and risk perception, which can aid development of public policy solutions toward communicating the severity and risks associated with natural disasters. PMID:23226230

  11. Using business plan development as a capstone project for MPH programs in Canada: validation through the student perspective.

    Science.gov (United States)

    Papadopoulos, Andrew; Britten, Nicole; Hatcher, Meghan; Rainville, Keira

    2013-10-01

    Master of Public Health (MPH) programs have been developed across Canada as a response to the need for adequately trained individuals to work in the public health sector. Educational institutions that deliver MPH programs have a responsibility to ensure that graduates of their program have the essential knowledge, skills and attitudes to begin a successful career in public health. The Public Health Agency of Canada has created the core competencies for public health to guide the development, delivery and evaluation of MPH programs. In Canada, a capstone project is the recommended method of evaluating the MPH graduate's ability to demonstrate proficiency in the public health core competencies. A business plan that develops the framework for a public health program is an ideal capstone project currently used in practice within the University of Guelph MPH program. This group assignment incorporates all 36 of the public health core competencies while providing students with a real-world public health experience, and should be considered for inclusion within MPH programs across Canada. Business planning provides students the opportunity to engage in practice-based learning, applying theoretical knowledge to practice. Further, the ability to develop realistic but financially feasible public health problems is an invaluable skill for MPH graduates. As the development of programs becomes more restricted and the continuation of other programs are under constant threat, the ability to develop a sound business plan is a required skill for individuals entering the public health sector, and will ensure students are able to maximize outcomes given tight fiscal budgets and limited resources.

  12. Intelligent Speed Assistance (ISA).

    NARCIS (Netherlands)

    2015-01-01

    Intelligent Speed Assistance (ISA) has been a promising type of advanced driver support system for some decades. From a technical point of view, large scale ISA implementation is possible in the short term. The different types of ISA are expected to have different effects on behaviour and traffic

  13. Classification and Analysis of Computer Network Traffic

    OpenAIRE

    Bujlow, Tomasz

    2014-01-01

    Traffic monitoring and analysis can be done for multiple different reasons: to investigate the usage of network resources, assess the performance of network applications, adjust Quality of Service (QoS) policies in the network, log the traffic to comply with the law, or create realistic models of traffic for academic purposes. We define the objective of this thesis as finding a way to evaluate the performance of various applications in a high-speed Internet infrastructure. To satisfy the obje...

  14. Life-Times of Simulated Traffic Jams

    OpenAIRE

    Nagel, K.

    1993-01-01

    We study a model for freeway traffic which includes strong noise taking into account the fluctuations of individual driving behavior. The model shows emergent traffic jams with a self-similar appearance near the throughput maximum of the traffic. The lifetime distribution of these jams shows a short scaling regime, which gets considerably longer if one reduces the fluctuations for driving at maximum speed but leaves the fluctuations for slowing down or accelerating unchanged. The outflow from...

  15. AN AUTOMATED RAILWAY STATION TRAFFIC CONTROL SYSTEM

    African Journals Online (AJOL)

    user

    2017-01-01

    Jan 1, 2017 ... Software simulation was carried out using the Proteus virtual system modeling ... system which helps in track switching and level crossing gate traffic control is capable of improving reliability, speed, .... Lane Switching Network.

  16. Evaluating Performances of Traffic Noise Models | Oyedepo ...

    African Journals Online (AJOL)

    Traffic noise in decibel dB(A) were measured at six locations using 407780A Integrating Sound Level Meter, while spot speed and traffic volume were collected with cine-camera. The predicted sound exposure level (SEL) was evaluated using Burgess, British and FWHA model. The average noise level obtained are 77.64 ...

  17. the factors that affect the free flow speed on an arterial in ilorin, nigeria

    African Journals Online (AJOL)

    user

    lower average free flow speed of commercial saloon cars on wet pavement than on dry pavement, with 12% percentage ... average space mean speed in a low volume traffic stream when ..... travel way width and number of traffic control units.

  18. FRIX-Traffic Analyzer And Transportation Assistant

    OpenAIRE

    Manuj Darbari,; Prateek Kumar; Singh Rakesh; Savitur Prakash

    2010-01-01

    This website specializes in giving traffic reports for a specific area. Much of our collected data comes from automatic sensors placed at various points around the motorway to monitor vehicle speeds. We have provided an accurate, up-to-date report which is normally faster than other mediums, such as radio. Typically our speed readings are updated every 3 minutes. Using this website a user can give the starting place and destination to the system. Depending on the prevalent traffic conditions,...

  19. 32 CFR 634.27 - Speed-measuring devices.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Speed-measuring devices. 634.27 Section 634.27 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) LAW ENFORCEMENT AND CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION Traffic Supervision § 634.27 Speed-measuring devices. Speed-measuring devices will be...

  20. The causes and prevalence of road traffic accidents amongst ...

    African Journals Online (AJOL)

    The study showed a prevalence of road traffic accidents of 47.9% in Benin City occurring more in day time and the common causes of road traffic accidents include careless driving, speed violation, brake failure, traffic violations, faulty overtaking, burst tyre, bad roads, alcohol use and armed robbery attack. Thus measures ...

  1. Model Predictive Control for Integrating Traffic Control Measures

    NARCIS (Netherlands)

    Hegyi, A.

    2004-01-01

    Dynamic traffic control measures, such as ramp metering and dynamic speed limits, can be used to better utilize the available road capacity. Due to the increasing traffic volumes and the increasing number of traffic jams the interaction between the control measures has increased such that local

  2. The Physics of Traffic Accidents

    Science.gov (United States)

    Knight, Peter

    1975-01-01

    Shows how physics can be used to analyze and prevent traffic accidents by determining critical speeds on curves, the behavior of motor cycles and stability of articulated vehicles, and the visibility that is needed to make a minor road junction safe. (MLH)

  3. Effects of automated speed enforcement in Montgomery County, Maryland, on vehicle speeds, public opinion, and crashes.

    Science.gov (United States)

    Hu, Wen; McCartt, Anne T

    2016-09-01

    In May 2007, Montgomery County, Maryland, implemented an automated speed enforcement program, with cameras allowed on residential streets with speed limits of 35 mph or lower and in school zones. In 2009, the state speed camera law increased the enforcement threshold from 11 to 12 mph over the speed limit and restricted school zone enforcement hours. In 2012, the county began using a corridor approach, in which cameras were periodically moved along the length of a roadway segment. The long-term effects of the speed camera program on travel speeds, public attitudes, and crashes were evaluated. Changes in travel speeds at camera sites from 6 months before the program began to 7½ years after were compared with changes in speeds at control sites in the nearby Virginia counties of Fairfax and Arlington. A telephone survey of Montgomery County drivers was conducted in Fall 2014 to examine attitudes and experiences related to automated speed enforcement. Using data on crashes during 2004-2013, logistic regression models examined the program's effects on the likelihood that a crash involved an incapacitating or fatal injury on camera-eligible roads and on potential spillover roads in Montgomery County, using crashes in Fairfax County on similar roads as controls. About 7½ years after the program began, speed cameras were associated with a 10% reduction in mean speeds and a 62% reduction in the likelihood that a vehicle was traveling more than 10 mph above the speed limit at camera sites. When interviewed in Fall 2014, 95% of drivers were aware of the camera program, 62% favored it, and most had received a camera ticket or knew someone else who had. The overall effect of the camera program in its modified form, including both the law change and the corridor approach, was a 39% reduction in the likelihood that a crash resulted in an incapacitating or fatal injury. Speed cameras alone were associated with a 19% reduction in the likelihood that a crash resulted in an

  4. SPEED COMPLIANCE IN FREEWAY VARIABLE SPEED LIMIT SYSTEM – CASE STUDY OF THE PRAGUE CITY RING

    Directory of Open Access Journals (Sweden)

    Michał MATOWICKI

    2016-03-01

    Full Text Available Many previous studies have confirmed the strong relationship between speed compliance and the frequency and severity of traffic accidents. Variable speed limit (VSL system as a measure to improve traffic safety enables the freeway system to change its posted speed limit based on various traffic and environmental conditions. Such system helps drivers to recognize the upcoming events, to adjust their driving style and in such way to address speed variation of the traffic flow. This is called speed harmonization. Although many studies researching the effect of VSL system on the traffic stream can be found, there are only few addressing its influence on the drivers behavior, particularly focusing on their tolerance limit and compliance, which has crucial meaning for future design of controlling algorithms. This study was prepared to inspect this grey area by studying the data from the VSL system at Prague city ring, describing the influence of the highway management system and its influence on drivers.

  5. A queuing model for road traffic simulation

    International Nuclear Information System (INIS)

    Guerrouahane, N.; Aissani, D.; Bouallouche-Medjkoune, L.; Farhi, N.

    2015-01-01

    We present in this article a stochastic queuing model for the raod traffic. The model is based on the M/G/c/c state dependent queuing model, and is inspired from the deterministic Godunov scheme for the road traffic simulation. We first propose a variant of M/G/c/c state dependent model that works with density-flow fundamental diagrams rather than density-speed relationships. We then extend this model in order to consider upstream traffic demand as well as downstream traffic supply. Finally, we show how to model a whole raod by concatenating raod sections as in the deterministic Godunov scheme

  6. Life Times of Simulated Traffic Jams

    Science.gov (United States)

    Nagel, Kai

    We study a model for freeway traffic which includes strong noise taking into account the fluctuations of individual driving behavior. The model shows emergent traffic jams with a self-similar appearance near the throughput maximum of the traffic. The lifetime distribution of these jams shows a short scaling regime, which gets considerably longer if one reduces the fluctuations when driving at maximum speed but leaves the fluctuations for slowing down or accelerating unchanged. The outflow from a traffic jam self-organizes into this state of maximum throughput.

  7. Teaching Note--Educating Public Health Social Work Professionals: Results from an MSW/MPH Program Outcomes Study

    Science.gov (United States)

    Ruth, Betty J.; Marshall, Jamie Wyatt; Velásquez, Esther E. M.; Bachman, Sara S.

    2015-01-01

    Dual-degree programs in public health and social work continue to proliferate, yet there has been little research on master's of social work (MSW)/master's of public health (MPH) graduates. The purpose of this study was to describe and better understand the self-reported professional experiences, identities, roles, and outcomes associated with 1…

  8. Effects of MPH-OROS on the organizational, time management, and planning behaviors of children with ADHD.

    Science.gov (United States)

    Abikoff, Howard; Nissley-Tsiopinis, Jenelle; Gallagher, Richard; Zambenedetti, Maurizio; Seyffert, Michael; Boorady, Roy; McCarthy, John

    2009-02-01

    To evaluate the effects of stimulant medication on organizational, time management, and planning (OTMP) in children with attention-deficit/hyperactivity disorder (ADHD) and ascertain whether OTMP is normalized with medication. Participants included 19 stimulant-naïve children with ADHD (aged 8-13 years) and impaired OTMP functioning, defined as greater than 1 SD below norms on the Children's Organizational Skills Scale. A double-blind, placebo-controlled, crossover design, with 4 weeks of each condition, evaluated medication (methylphenidate-osmotic-release oral system [MPH-OROS]) effects on OTMP, based on the parent and teacher versions of the Children's Organizational Skills Scale. The parent and teacher Swanson, Nolan, and Pelham, Version IV, rating scales assessed ADHD symptoms. "Not impaired" in OTMP was defined as no longer meeting study entry criteria, and "not impaired" in ADHD symptoms was defined as having mean Swanson, Nolan, and Pelham, Version IV, scores of < or = 1.0. MPH-OROS significantly improved children's OTMP behaviors. These improvements were correlated with significant reductions in ADHD symptoms. However, most of the children (61%) continued to show significant OTMP impairments on MPH-OROS. The MPH-OROS reduced children's OTMP deficits, and these improvements were associated with improvements in ADHD symptoms. Some children remained impaired in OTMP even after effective stimulant treatment of ADHD symptoms. These youngsters may require other treatments that target OTMP deficits.

  9. Effects of MPH-OROS on the Organizational, Time Management, and Planning Behaviors of Children with ADHD

    Science.gov (United States)

    Abikoff, Howard; Nissley-Tsiopinis, Jenelle; Gallagher, Richard; Zambenedetti, Maurizio; Seyffert, Michael; Boorady, Roy; McCarthy, John

    2009-01-01

    A double-blind, placebo-controlled, crossover design study was done to evaluate the effects of methylphenidate-osmotic-release oral systems (MPH-OROS) on the organization, time management, and planning (OTMP) of children with attention deficit hyperactivity disorder (ADHD). Results show significant improvements on the OTMP of children with ADHD in…

  10. Traffic Perturbation

    CERN Multimedia

    C. Colloca TS/FM

    2004-01-01

    TS/FM group informs you that, for the progress of the works at the Prévessin site entrance, some perturbation of the traffic may occur during the week between the 14th and 18th of June for a short duration. Access will be assured at any time. For more information, please contact 160239. C. Colloca TS/FM

  11. The Smc5/6 complex regulates the yeast Mph1 helicase at RNA-DNA hybrid-mediated DNA damage

    DEFF Research Database (Denmark)

    Lafuente-Barquero, Juan; Luke-Glaser, Sarah; Graf, Marco

    2017-01-01

    of Fanconi anemia protein M (FANCM), is required for cell viability in the absence of RNase H enzymes. The integrity of the Mph1 helicase domain is crucial to prevent the accumulation of RNA-DNA hybrids and RNA-DNA hybrid-dependent DNA damage, as determined by Rad52 foci. Mph1 forms foci when RNA-DNA hybrids...

  12. Designing and conducting MD/MPH dual degree program in the Medical School of Shiraz University of Medical Sciences.

    Science.gov (United States)

    Salehi, Alireza; Hashemi, Neda; Saber, Mahboobeh; Imanieh, Mohammad Hadi

    2015-07-01

    Many studies have focused on the need of health systems to educated physicians in the clinical prevention, research methodology, epidemiology and health care management and emphasize the important role of this training in the public health promotion. On this basis, Shiraz University of Medical Sciences (SUMS) has established MD/MPH dual degree program since the year 2012. In the current study, Delphi technique was used. Both qualitative and quantitative methods were applied in the Delphi process. The Delphi team members including experts with extensive experience in teaching, research and administration in the field of educational management and health/medical education reached consensus in almost 86% of the questionnaire items through three Delphi rounds. MD/MPH program for SUMS was designed based on the items agreed and thematic analysis used in these rounds. The goals, values, mission and program requirements including the period, the entrance condition, and the number of units, and certification were determined. Accordingly, the courses of the program are presented in parallel with the MD education period. MPH courses consist of 35 units including 16 obligatory and 15 voluntary ones. Designing MD/MPH program in SUMS based on the existent models in the universities in different countries, compatible with educational program of this university and needs of national health system in Iran, can be a beneficial measure towards promoting the students' knowledge and theoretical/practical skills in both individual and social level. Performing some additional research to assess the MD/MPH program and some cohort studies to evaluate the effect of this program on the students' future professional life is recommended.

  13. Standardization of light signals for road traffic control. Contribution in: Speed enforcement, visibility, and effects of traffic control measures on drivers, Transportation Research Record No. 811, p. 14-15, Transportation Research Board, National Academies of Sciences, Washington, D.C., 1981.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1981-01-01

    A recent technical report on road-traffic-control signals prepared by the International Commission on Illumination is briefly discussed. The report represents a first step toward international standardisation of traffic signal lights in order to benefit trade and transportation. The principal

  14. Variable Speed Limit (VSL) - Best Management Practice [Summary

    Science.gov (United States)

    2012-01-01

    In variable speed limit (VSL) zones, the speed : limit changes in response to traffic congestion, : adverse weather, or road conditions. VSL zones are : often highly automated and have been employed : successfully in several U.S. and European : locat...

  15. Traffic data collection and anonymous vehicle detection using wireless sensor networks : research summary.

    Science.gov (United States)

    2012-05-01

    Problem: : Most Intelligent Transportation System (ITS) applications require distributed : acquisition of various traffic metrics such as traffic speed, volume, and density. : The existing measurement technologies, such as inductive loops, infrared, ...

  16. On vehicular traffic data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brics, Martins; Mahnke, Reinhard [Institute of Physics, Rostock University (Germany)

    2011-07-01

    This contribution consists of analysis of empirical vehicular traffic flow data. The main focus lies on the Next Generation Simulation (NGSIM) data. The first findings show that there are artificial structures within the data due to errors of monitoring as well as smoothing position measurement data. As a result speed data show discretisation in 5 feet per second. The aim of this investigation is to construct microscopic traffic flow models which are in agreement to the analysed empirical data. The ongoing work follows the subject of research summarized by Christof Liebe in his PhD thesis entitled ''Physics of traffic flow: Empirical data and dynamical models'' (Rostock, 2010).

  17. Innovating in Health Care Management Education: Development of an Accelerated MBA and MPH Degree Program at Yale

    Science.gov (United States)

    Forman, Howard P.; Pistell, Anne F.; Nembhard, Ingrid M.

    2015-01-01

    Increasingly, there is recognition of the need for individuals with expertise in both management and public health to help health care organizations deliver high-quality and cost-effective care. The Yale School of Public Health and Yale School of Management began offering an accelerated Master of Business Administration (MBA) and Master of Public Health (MPH) joint degree program in the summer of 2014. This new program enables students to earn MBA and MPH degrees simultaneously from 2 fully accredited schools in 22 months. Students will graduate with the knowledge and skills needed to become innovative leaders of health care organizations. We discuss the rationale for the program, the developmental process, the curriculum, benefits of the program, and potential challenges. PMID:25706023

  18. Innovating in health care management education: development of an accelerated MBA and MPH degree program at Yale.

    Science.gov (United States)

    Pettigrew, Melinda M; Forman, Howard P; Pistell, Anne F; Nembhard, Ingrid M

    2015-03-01

    Increasingly, there is recognition of the need for individuals with expertise in both management and public health to help health care organizations deliver high-quality and cost-effective care. The Yale School of Public Health and Yale School of Management began offering an accelerated Master of Business Administration (MBA) and Master of Public Health (MPH) joint degree program in the summer of 2014. This new program enables students to earn MBA and MPH degrees simultaneously from 2 fully accredited schools in 22 months. Students will graduate with the knowledge and skills needed to become innovative leaders of health care organizations. We discuss the rationale for the program, the developmental process, the curriculum, benefits of the program, and potential challenges.

  19. ON THE ARRIVAL TRAFFIC FLOW ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Nikita A. Assorov

    2017-01-01

    Full Text Available This article is about air traffic flow organization, ICAO regulations describe the organizing of traffic flow as one of the purposes of air traffic control, but they don’t state exactly at what point the flow has to be organized and metered. The flight phase, where air traffic controller interferes with his instructions in order to begin organizing of all aircraft landing at a certain airport depends on the actual traffic volume per hour, airspace capacity and design.The example of air traffic situation in Moscow Domodedovo airport is described in the article, with runway 32 right in use, no significant weather, real usage of STARs, considering all the ICAO and Russian Federation regulations regarding speed control with the restrictions mentioned in AIP of Moscow Domodedovo. The purpose of the experiment is to prove the need of metering the air traffic flow on the entry points in Moscow TMA, because in case of unorganized air traffic flow approach controllers will have additional unnecessary workload.The conducted calculations show, that only 3 aircraft entering TMA on the same distance from initial approach point can be handled using only speed control and existing standard arrival procedures, in all other cases vectoring or holding areas should be used.In order to avoid such situations and increase the number of the aircraft that can be handled by the approach controller with less instructions, all the traffic arriving on the TMA entry point has to be metered by area control centre, because the air traffic control unit has much more space and time for long term speed control modifications, e.g. ±0,02 Mach. In conclusion a simple rule comes to mind – the bigger inbound traffic is, the earlier one has to organize it, in order to do it speed control, radar vectors, miles-in-trail can be used. Also new equipment and technology can help air traffic controller with this task, e.g. AMAN (arrival manager, in addition to this, the experience of

  20. System And Method For Monitoring Traffic While Preserving Personal Privacy

    KAUST Repository

    Canepa, Edward

    2015-08-06

    A traffic monitoring system and method for mapping traffic speed and density while preserving privacy. The system can include fixed stations that make up a network and mobile probes that are associated with vehicles. The system and method do not gather, store, or transmit any unique or identifying information, and thereby preserves the privacy of members of traffic. The system and method provide real-time traffic density and speed mapping. The system and method can further be integrated with a complementary flood monitoring system and method.

  1. Active Traffic Management in Michigan

    OpenAIRE

    Johnson, Pat

    2018-01-01

    The US 23 Flex Route is the first active traffic management (ATM) project in the state of Michigan. This route utilizes overhead lane control gantries equipped with various intelligent transportation system (ITS) equipment to facilitate the following ATM strategies: dynamic shoulder use, dynamic lane control, variable speed advisories, and queue warning. The focus of this presentation is how the project team overcame several challenges during the planning, design, and system management phases...

  2. Fixed Point Learning Based Intelligent Traffic Control System

    Science.gov (United States)

    Zongyao, Wang; Cong, Sui; Cheng, Shao

    2017-10-01

    Fixed point learning has become an important tool to analyse large scale distributed system such as urban traffic network. This paper presents a fixed point learning based intelligence traffic network control system. The system applies convergence property of fixed point theorem to optimize the traffic flow density. The intelligence traffic control system achieves maximum road resources usage by averaging traffic flow density among the traffic network. The intelligence traffic network control system is built based on decentralized structure and intelligence cooperation. No central control is needed to manage the system. The proposed system is simple, effective and feasible for practical use. The performance of the system is tested via theoretical proof and simulations. The results demonstrate that the system can effectively solve the traffic congestion problem and increase the vehicles average speed. It also proves that the system is flexible, reliable and feasible for practical use.

  3. Traffic signal synchronization.

    Science.gov (United States)

    Huang, Ding-wei; Huang, Wei-neng

    2003-05-01

    The benefits of traffic signal synchronization are examined within the cellular automata approach. The microsimulations of traffic flow are obtained with different settings of signal period T and time delay delta. Both numerical results and analytical approximations are presented. For undersaturated traffic, the green-light wave solutions can be realized. For saturated traffic, the correlation among the traffic signals has no effect on the throughput. For oversaturated traffic, the benefits of synchronization are manifest only when stochastic noise is suppressed.

  4. SignalGuru: Leveraging mobile phones for collaborative traffic signal schedule advisory

    OpenAIRE

    Koukoumidis, Emmanouil; Peh, Li-Shiuan; Martonosi, Margaret

    2011-01-01

    While traffic signals are necessary to safely control competing flows of traffic, they inevitably enforce a stop-and-go movement pattern that increases fuel consumption, reduces traffic flow and causes traffic jams. These side effects can be alleviated by providing drivers and their onboard computational devices (e.g., vehicle computer, smartphone) with information about the schedule of the traffic signals ahead. Based on when the signal ahead will turn green, drivers can then adjust speed so...

  5. TRAFFIC SIMULATION FOR MIXED TRAFFIC SYSTEMS

    African Journals Online (AJOL)

    EGETE

    2012-05-04

    May 4, 2012 ... Traffic problem is classified into single and mixed, especially in most developing countries, where motorbikes are ..... The traffic light control system presented by its location on ... multi-destination dynamic routing and real-time.

  6. Influencing speeding behaviour through preventative police enforcement. Paper presented at the VIth International Road Safety Organisation PRI World Congress on `Marketing traffic safety', 3-6 October 1994, Cape Town, South Africa.

    NARCIS (Netherlands)

    Wesemann, P.

    1994-01-01

    This paper considers the effect of speed on road safety and how to influence speeding behaviour. The results that can be achieved through police enforcement combined with information campaigns are discussed with reference to projects carried out in the Netherlands. The cost implications are

  7. Traffic State Estimation Using Connected Vehicles and Stationary Detectors

    Directory of Open Access Journals (Sweden)

    Ellen F. Grumert

    2018-01-01

    Full Text Available Real-time traffic state estimation is of importance for efficient traffic management. This is especially the case for traffic management systems that require fast detection of changes in the traffic conditions in order to apply an effective control measure. In this paper, we propose a method for estimating the traffic state and speed and density, by using connected vehicles combined with stationary detectors. The aim is to allow fast and accurate estimation of changes in the traffic conditions. The proposed method does only require information about the speed and the position of connected vehicles and can make use of sparsely located stationary detectors to limit the dependence on the infrastructure equipment. An evaluation of the proposed method is carried out by microscopic traffic simulation. The traffic state estimated using the proposed method is compared to the true simulated traffic state. Further, the density estimates are compared to density estimates from one detector-based method, one combined method, and one connected-vehicle-based method. The results of the study show that the proposed method is a promising alternative for estimating the traffic state in traffic management applications.

  8. Connect & Drive - On the use of vehicle-to-vehicle communications to increase Traffic Stability and Efficiency

    NARCIS (Netherlands)

    Heijenk, Geert

    2009-01-01

    At moderate to high traffic densities, road traffic exhibits an unstable behavior, resulting in decrease traffic efficiency. One of the phenomena that can be observed at these densities is the propagation of shock waves against the flow of traffic, which seriously reduce the speed of vehicles. The

  9. A measure theoretic approach to traffic flow optimization on networks

    OpenAIRE

    Cacace, Simone; Camilli, Fabio; De Maio, Raul; Tosin, Andrea

    2018-01-01

    We consider a class of optimal control problems for measure-valued nonlinear transport equations describing traffic flow problems on networks. The objective isto minimise/maximise macroscopic quantities, such as traffic volume or average speed,controlling few agents, for example smart traffic lights and automated cars. The measuretheoretic approach allows to study in a same setting local and nonlocal drivers interactionsand to consider the control variables as additional measures interacting ...

  10. 45 MPH 6,000-Pound and 10,000-Pound Rough Terrain Fork Lift Truck Feasibility Study.

    Science.gov (United States)

    1986-06-24

    Airport Post Office Box 66911 Chicago, IL 60666 NPN Security Classification of This Page REPORT DOCUMENTATION PAGE la . Report Security Classification...HOP Unausended Duadin., 20 - I: - 1 1.8 Inch RMS Road 14 la -3 * Clam C (0.93 Inch RMS) Rod w 12 10 10 Per~cent 9 P 7 U. 3 Percent 3 2 0 20 40 SPM...elm 10 67- * * 3 o *" - .2 0 20 40 W (mph) 4/2/ SOJA Figure 75. Rear Wheel Hop on Four Road Surfaces (10K RTFLT Unsuspended Baseline) " Page 93 Adding

  11. Robust, Optimal, Predictive, and Integrated Road Traffic Control : Research proposal

    NARCIS (Netherlands)

    Van de Weg, G.S.; Hegyi, A.; Hoogendoorn, S.P.

    2014-01-01

    The development of control strategies for traffic lights, ramp metering installations, and variable speed limits to improve the throughput of road traffic networks can contribute to a more efficient use of road networks. In this project, a hierarchical controller will be developed for the

  12. Efficient Algorithms for Network-Wide Road Traffic Control

    NARCIS (Netherlands)

    van de Weg, G.S.

    2017-01-01

    Controlling road traffic networks is a complex problem. One of the difficulties is the coordination of actuators, such as traffic lights, variables speed limits, ramp metering and route guidance, with the aim to improve the network performance over a near-future time horizon. This dissertation

  13. System And Method For Monitoring Traffic While Preserving Personal Privacy

    KAUST Repository

    Canepa, Edward; Claudel, Christian G.; Shamim, Atif; Dehwah, Ahmad H.; Mousa, Mustafa; Jiang, Jiming

    2015-01-01

    not gather, store, or transmit any unique or identifying information, and thereby preserves the privacy of members of traffic. The system and method provide real-time traffic density and speed mapping. The system and method can further be integrated with a

  14. A theory of traffic congestion at moving bottlenecks

    Energy Technology Data Exchange (ETDEWEB)

    Kerner, Boris S [Daimler AG, GR/PTF, HPC: G021, 71059 Sindelfingen (Germany); Klenov, Sergey L, E-mail: boris.kerner@daimler.co [Department of Physics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Moscow Region (Russian Federation)

    2010-10-22

    The physics of traffic congestion occurring at a moving bottleneck on a multi-lane road is revealed based on the numerical analyses of vehicular traffic with a discrete stochastic traffic flow model in the framework of three-phase traffic theory. We find that there is a critical speed of a moving bottleneck at which traffic breakdown, i.e. a first-order phase transition from free flow to synchronized flow, occurs spontaneously at the moving bottleneck, if the flow rate upstream of the bottleneck is great enough. The greater the flow rate, the higher the critical speed of the moving bottleneck. A diagram of congested traffic patterns at the moving bottleneck is found, which shows regions in the flow-rate-moving-bottleneck-speed plane in which congested patterns emerge spontaneously or can be induced through large enough disturbances in an initial free flow. A comparison of features of traffic breakdown and resulting congested patterns at the moving bottleneck with known ones at an on-ramp (and other motionless) bottleneck is made. Nonlinear features of complex interactions and transformations of congested traffic patterns occurring at on- and off-ramp bottlenecks due to the existence of the moving bottleneck are found. The physics of the phenomenon of traffic congestion due to 'elephant racing' on a multi-lane road is revealed.

  15. A theory of traffic congestion at moving bottlenecks

    International Nuclear Information System (INIS)

    Kerner, Boris S; Klenov, Sergey L

    2010-01-01

    The physics of traffic congestion occurring at a moving bottleneck on a multi-lane road is revealed based on the numerical analyses of vehicular traffic with a discrete stochastic traffic flow model in the framework of three-phase traffic theory. We find that there is a critical speed of a moving bottleneck at which traffic breakdown, i.e. a first-order phase transition from free flow to synchronized flow, occurs spontaneously at the moving bottleneck, if the flow rate upstream of the bottleneck is great enough. The greater the flow rate, the higher the critical speed of the moving bottleneck. A diagram of congested traffic patterns at the moving bottleneck is found, which shows regions in the flow-rate-moving-bottleneck-speed plane in which congested patterns emerge spontaneously or can be induced through large enough disturbances in an initial free flow. A comparison of features of traffic breakdown and resulting congested patterns at the moving bottleneck with known ones at an on-ramp (and other motionless) bottleneck is made. Nonlinear features of complex interactions and transformations of congested traffic patterns occurring at on- and off-ramp bottlenecks due to the existence of the moving bottleneck are found. The physics of the phenomenon of traffic congestion due to 'elephant racing' on a multi-lane road is revealed.

  16. 75 FR 25927 - Vehicle/Track Interaction Safety Standards; High-Speed and High Cant Deficiency Operations

    Science.gov (United States)

    2010-05-10

    ... Transporte;* Sheet Metal Workers International Association (SMWIA); Tourist Railway Association, Inc... over their intended service routes using instrumented wheelsets to directly measure forces between the... Carbody Acceleration Events During route testing of the MARC-III multi-level car at speeds to 125 m.p.h...

  17. Leadership training for radiologists: a survey of opportunities and participants in MBA and MPH programs by medical students, residents, and current chairpersons.

    Science.gov (United States)

    Baker, Stephen; Daginawala, Naznin

    2011-08-01

    The aim of this study was to determine opportunities for students and trainees to obtain an MPH or MBA degree during either medical school or radiology residency and to determine the prevalence of such degree possession by chairpersons in radiology. All allopathic medical schools in the United States were surveyed to chart the number of MD/MPH and MD/MBA degree programs available to students. Program directors were contacted to assess the number of MPH or MBA courses of study administratively related to their residencies. Also, an e-mail survey was sent to all members of the Society of Chairs of Academic Radiology Departments inquiring whether each chairperson had earned an additional degree. Currently, 81 allopathic medical schools in the United States offer MD/MPH degrees, and 52 offer MD/MBA degrees. Six residencies provide access to MPH programs, and 3 residencies provide the opportunity to pursue an MBA in conjunction with residency. Of these, only 1 MPH program and no MBA programs had trainees enrolled at present. Twenty-six percent of the chairpersons surveyed possessed advanced degrees other than MDs. There has been rapid growth in the number of MD/MPH and MD/MBA programs available to medical students. However, there is a scarcity of similar programs accessible to trainees during or just after residency training. To assist motivated radiologists interested in leading our profession, opportunities should expand both in formal degree-granting programs and through certificate-sanctioned course series to address relevant issues of leadership and management pertinent to our specialty. Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. Intelligent Traffic Information System a Real-Time Traffic Information System on the Shiraz Bypass

    Directory of Open Access Journals (Sweden)

    Sodagaran Amir

    2016-01-01

    Full Text Available Real-time traffic information system is an Intelligent Transportation System (ITS that allows commuters to make their traveling plan better. In this regard, an intelligent and real-time traffic information system was developed based on the video detection and an image processing algorithm was applied to measure traffic-flow according to the average speed of vehicles. Then, traffic status of each pass way is broadcasted to the electronic boards installed on all decision making entrance / exit. Different levels of congestion related to the routes ahead are shown on the boards with different colors in order to assist commuters. This system was implemented on the Shiraz Dry River’s bypasses which account as vital routes to moderate traffic of city center. Experimental results are promising due to the proximity of determined traffic status by the system compared to the detection done by traffic experts. Average speed improvement is another result of using this system. This intelligent system developed and implemented in Shiraz city for the first time in Iran.s.

  19. FAST DRAWING OF TRAFFIC SIGN USING MOBILE MAPPING SYSTEM

    Directory of Open Access Journals (Sweden)

    Q. Yao

    2016-06-01

    Full Text Available Traffic sign provides road users with the specified instruction and information to enhance traffic safety. Automatic detection of traffic sign is important for navigation, autonomous driving, transportation asset management, etc. With the advance of laser and imaging sensors, Mobile Mapping System (MMS becomes widely used in transportation agencies to map the transportation infrastructure. Although many algorithms of traffic sign detection are developed in the literature, they are still a tradeoff between the detection speed and accuracy, especially for the large-scale mobile mapping of both the rural and urban roads. This paper is motivated to efficiently survey traffic signs while mapping the road network and the roadside landscape. Inspired by the manual delineation of traffic sign, a drawing strategy is proposed to quickly approximate the boundary of traffic sign. Both the shape and color prior of the traffic sign are simultaneously involved during the drawing process. The most common speed-limit sign circle and the statistic color model of traffic sign are studied in this paper. Anchor points of traffic sign edge are located with the local maxima of color and gradient difference. Starting with the anchor points, contour of traffic sign is drawn smartly along the most significant direction of color and intensity consistency. The drawing process is also constrained by the curvature feature of the traffic sign circle. The drawing of linear growth is discarded immediately if it fails to form an arc over some steps. The Kalman filter principle is adopted to predict the temporal context of traffic sign. Based on the estimated point,we can predict and double check the traffic sign in consecutive frames.The event probability of having a traffic sign over the consecutive observations is compared with the null hypothesis of no perceptible traffic sign. The temporally salient traffic sign is then detected statistically and automatically as the rare

  20. Fast Drawing of Traffic Sign Using Mobile Mapping System

    Science.gov (United States)

    Yao, Q.; Tan, B.; Huang, Y.

    2016-06-01

    Traffic sign provides road users with the specified instruction and information to enhance traffic safety. Automatic detection of traffic sign is important for navigation, autonomous driving, transportation asset management, etc. With the advance of laser and imaging sensors, Mobile Mapping System (MMS) becomes widely used in transportation agencies to map the transportation infrastructure. Although many algorithms of traffic sign detection are developed in the literature, they are still a tradeoff between the detection speed and accuracy, especially for the large-scale mobile mapping of both the rural and urban roads. This paper is motivated to efficiently survey traffic signs while mapping the road network and the roadside landscape. Inspired by the manual delineation of traffic sign, a drawing strategy is proposed to quickly approximate the boundary of traffic sign. Both the shape and color prior of the traffic sign are simultaneously involved during the drawing process. The most common speed-limit sign circle and the statistic color model of traffic sign are studied in this paper. Anchor points of traffic sign edge are located with the local maxima of color and gradient difference. Starting with the anchor points, contour of traffic sign is drawn smartly along the most significant direction of color and intensity consistency. The drawing process is also constrained by the curvature feature of the traffic sign circle. The drawing of linear growth is discarded immediately if it fails to form an arc over some steps. The Kalman filter principle is adopted to predict the temporal context of traffic sign. Based on the estimated point,we can predict and double check the traffic sign in consecutive frames.The event probability of having a traffic sign over the consecutive observations is compared with the null hypothesis of no perceptible traffic sign. The temporally salient traffic sign is then detected statistically and automatically as the rare event of having a

  1. Crowding effects in vehicular traffic.

    Directory of Open Access Journals (Sweden)

    Jay Samuel L Combinido

    Full Text Available While the impact of crowding on the diffusive transport of molecules within a cell is widely studied in biology, it has thus far been neglected in traffic systems where bulk behavior is the main concern. Here, we study the effects of crowding due to car density and driving fluctuations on the transport of vehicles. Using a microscopic model for traffic, we found that crowding can push car movement from a superballistic down to a subdiffusive state. The transition is also associated with a change in the shape of the probability distribution of positions from a negatively-skewed normal to an exponential distribution. Moreover, crowding broadens the distribution of cars' trap times and cluster sizes. At steady state, the subdiffusive state persists only when there is a large variability in car speeds. We further relate our work to prior findings from random walk models of transport in cellular systems.

  2. INTEGRATED SPEED ESTIMATION MODEL FOR MULTILANE EXPREESSWAYS

    Science.gov (United States)

    Hong, Sungjoon; Oguchi, Takashi

    In this paper, an integrated speed-estimation model is developed based on empirical analyses for the basic sections of intercity multilane expressway un der the uncongested condition. This model enables a speed estimation for each lane at any site under arb itrary highway-alignment, traffic (traffic flow and truck percentage), and rainfall conditions. By combin ing this model and a lane-use model which estimates traffic distribution on the lanes by each vehicle type, it is also possible to es timate an average speed across all the lanes of one direction from a traffic demand by vehicle type under specific highway-alignment and rainfall conditions. This model is exp ected to be a tool for the evaluation of traffic performance for expressways when the performance me asure is travel speed, which is necessary for Performance-Oriented Highway Planning and Design. Regarding the highway-alignment condition, two new estimators, called effective horizo ntal curvature and effective vertical grade, are proposed in this paper which take into account the influence of upstream and downstream alignment conditions. They are applied to the speed-estimation model, and it shows increased accuracy of the estimation.

  3. Fast Traffic Sign Recognition with a Rotation Invariant Binary Pattern Based Feature

    Directory of Open Access Journals (Sweden)

    Shouyi Yin

    2015-01-01

    Full Text Available Robust and fast traffic sign recognition is very important but difficult for safe driving assistance systems. This study addresses fast and robust traffic sign recognition to enhance driving safety. The proposed method includes three stages. First, a typical Hough transformation is adopted to implement coarse-grained location of the candidate regions of traffic signs. Second, a RIBP (Rotation Invariant Binary Pattern based feature in the affine and Gaussian space is proposed to reduce the time of traffic sign detection and achieve robust traffic sign detection in terms of scale, rotation, and illumination. Third, the techniques of ANN (Artificial Neutral Network based feature dimension reduction and classification are designed to reduce the traffic sign recognition time. Compared with the current work, the experimental results in the public datasets show that this work achieves robustness in traffic sign recognition with comparable recognition accuracy and faster processing speed, including training speed and recognition speed.

  4. Toward Greater Understanding of the Relationship between Public Perceptions of Speed, Speed Laws, and Safety

    Science.gov (United States)

    2018-02-01

    Speed continues to be a leading factor contributing to traffic fatalities in the U.S., implicated in over 9,500 deaths in 2015. Despite this, in recent years, some states have moved toward more lenient speed enforcement regimes. A public choice probl...

  5. Traffic management simulation development : summary.

    Science.gov (United States)

    2011-01-01

    Increasingly, Florida traffic is monitored electronically by components of the Intelligent Traffic System (ITS), which send data to regional traffic management centers and assist management of traffic flows and incident response using software called...

  6. Traffic planning for non-homogeneous traffic

    Indian Academy of Sciences (India)

    Vehicles based on similar traffic operating characteristics are grouped into ... of distances to the video monitor involved using a measuring wheel to mark ... Secondly, the observers reviewed the videotape to sample traffic entity ...... makes a strong case for including service lanes for slow moving vehicles for improving the.

  7. State Traffic Safety Information

    Data.gov (United States)

    Department of Transportation — The State Traffic Safety Information (STSI) portal is part of the larger Fatality Analysis Reporting System (FARS) Encyclopedia. STSI provides state-by-state traffic...

  8. Traffic management simulation development.

    Science.gov (United States)

    2011-01-03

    Microscopic simulation can provide significant support to traffic management center (TMC) operations. However, traffic simulation applications require data that are expensive and time-consuming to collect. Data collected by TMCs can be used as a prim...

  9. Are Students Aware of the Speed Limits on a University Campus?

    Science.gov (United States)

    Brooks, Johnell; Raines, Stephanie; Klein, Nathan; Crisler, Matt; Wills, Rebekkah; Mossey, Mary; Koon, Beatrice; McKibben, Eric; Ogle, Jennifer; Robinson, Geary

    2010-01-01

    Driving speed is an important traffic safety issue. The lack of adherence to posted speed limits is a safety concern, especially on university campuses where the populations of drivers are at increased risk for crashes involving speeding due to their young age. Thus, driver speed and knowledge of speed limits on university campuses is an important…

  10. Vehicle Speed Estimation and Forecasting Methods Based on Cellular Floating Vehicle Data

    Directory of Open Access Journals (Sweden)

    Wei-Kuang Lai

    2016-02-01

    Full Text Available Traffic information estimation and forecasting methods based on cellular floating vehicle data (CFVD are proposed to analyze the signals (e.g., handovers (HOs, call arrivals (CAs, normal location updates (NLUs and periodic location updates (PLUs from cellular networks. For traffic information estimation, analytic models are proposed to estimate the traffic flow in accordance with the amounts of HOs and NLUs and to estimate the traffic density in accordance with the amounts of CAs and PLUs. Then, the vehicle speeds can be estimated in accordance with the estimated traffic flows and estimated traffic densities. For vehicle speed forecasting, a back-propagation neural network algorithm is considered to predict the future vehicle speed in accordance with the current traffic information (i.e., the estimated vehicle speeds from CFVD. In the experimental environment, this study adopted the practical traffic information (i.e., traffic flow and vehicle speed from Taiwan Area National Freeway Bureau as the input characteristics of the traffic simulation program and referred to the mobile station (MS communication behaviors from Chunghwa Telecom to simulate the traffic information and communication records. The experimental results illustrated that the average accuracy of the vehicle speed forecasting method is 95.72%. Therefore, the proposed methods based on CFVD are suitable for an intelligent transportation system.

  11. Traffic Noise Assessment at Residential Areas in Skudai, Johor

    Science.gov (United States)

    Sulaiman, F. S.; Darus, N.; Mashros, N.; Haron, Z.; Yahya, K.

    2018-03-01

    Vehicles passing by on roadways in residential areas may produce unpleasant traffic noise that affects the residents. This paper presents the traffic noise assessment of three selected residential areas located in Skudai, Johor. The objectives of this study are to evaluate traffic characteristics at selected residential areas, determine related noise indices, and assess impact of traffic noise. Traffic characteristics such as daily traffic volume and vehicle speed were evaluated using automatic traffic counter (ATC). Meanwhile, noise indices like equivalent continuous sound pressure level (LAeq), noise level exceeded 10% (L10) and 90% (L90) of measurement time were determined using sound level meter (SLM). Besides that, traffic noise index (TNI) and noise pollution level (LNP) were calculated based on the measured noise indices. The results showed an increase in noise level of 60 to 70 dBA maximum due to increase in traffic volume. There was also a significant change in noise level of more than 70 dBA even though average vehicle speed did not vary significantly. Nevertheless, LAeq, TNI, and LNP values for all sites during daytime were lower than the maximum recommended levels. Thus, residents in the three studied areas were not affected in terms of quality of life and health.

  12. Traffic and related self-driven many-particle systems

    Science.gov (United States)

    Helbing, Dirk

    2001-10-01

    Since the subject of traffic dynamics has captured the interest of physicists, many surprising effects have been revealed and explained. Some of the questions now understood are the following: Why are vehicles sometimes stopped by ``phantom traffic jams'' even though drivers all like to drive fast? What are the mechanisms behind stop-and-go traffic? Why are there several different kinds of congestion, and how are they related? Why do most traffic jams occur considerably before the road capacity is reached? Can a temporary reduction in the volume of traffic cause a lasting traffic jam? Under which conditions can speed limits speed up traffic? Why do pedestrians moving in opposite directions normally organize into lanes, while similar systems ``freeze by heating''? All of these questions have been answered by applying and extending methods from statistical physics and nonlinear dynamics to self-driven many-particle systems. This article considers the empirical data and then reviews the main approaches to modeling pedestrian and vehicle traffic. These include microscopic (particle-based), mesoscopic (gas-kinetic), and macroscopic (fluid-dynamic) models. Attention is also paid to the formulation of a micro-macro link, to aspects of universality, and to other unifying concepts, such as a general modeling framework for self-driven many-particle systems, including spin systems. While the primary focus is upon vehicle and pedestrian traffic, applications to biological or socio-economic systems such as bacterial colonies, flocks of birds, panics, and stock market dynamics are touched upon as well.

  13. Imitation dynamics in a game of traffic

    Science.gov (United States)

    Paissan, Gabriel; Abramson, Guillermo

    2013-04-01

    We study a model of traffic where drivers adopt different behavioral strategies. These can be cooperative or defective according to a driver abiding or not by a traffic rule. Drivers can change their strategy by imitating the majority, with a rule that depends on the strategies with which they have interacted. These interactions occur at intersections, where vehicles pay a temporal cost according to their strategy. We analyze the conditions under which different strategy compositions represent an advantage in the system velocity. We found that the cooperators' mean speed is higher than the defectors' even when the vehicle density is large. However, defectors can obtain benefits in their mean speed when they are a minority in an essentially cooperative population. The presence of a core of educated drivers, who persist firmly in a cooperative behavior, optimizes the speed in the system, especially for intermediate values of vehicular density and higher temporal costs.

  14. Blind haste: As light decreases, speeding increases.

    Science.gov (United States)

    de Bellis, Emanuel; Schulte-Mecklenbeck, Michael; Brucks, Wernher; Herrmann, Andreas; Hertwig, Ralph

    2018-01-01

    Worldwide, more than one million people die on the roads each year. A third of these fatal accidents are attributed to speeding, with properties of the individual driver and the environment regarded as key contributing factors. We examine real-world speeding behavior and its interaction with illuminance, an environmental property defined as the luminous flux incident on a surface. Drawing on an analysis of 1.2 million vehicle movements, we show that reduced illuminance levels are associated with increased speeding. This relationship persists when we control for factors known to influence speeding (e.g., fluctuations in traffic volume) and consider proxies of illuminance (e.g., sight distance). Our findings add to a long-standing debate about how the quality of visual conditions affects drivers' speed perception and driving speed. Policy makers can intervene by educating drivers about the inverse illuminance‒speeding relationship and by testing how improved vehicle headlights and smart road lighting can attenuate speeding.

  15. Impacts of Traffic Noise and Traffic Volume on Birds of Roadside Habitats

    Directory of Open Access Journals (Sweden)

    Kirsten M. Parris

    2009-06-01

    vulnerable to their impacts. Other management options include reducing the speed and/or volume of traffic on such roads to an acceptably low level. Ours is the first study to investigate the effect of traffic noise on the singing behavior of birds in the southern hemisphere.

  16. Environmental Assessment for Mid-Bay Bridge Connector, Eglin Air Force Base, Florida

    Science.gov (United States)

    2008-12-05

    Year Average Speed (mph) AADT VPH Receptor Max 1-Hr Conc (ppm) Max 8-Hr Conc (ppm) Proposed Action 2001 45 17,400 981 Proposed...Speed (mph) AADT VPH Receptor Max 1-Hr Conc (ppm) Max 8-Hr Conc (ppm) Alternative C 2001 45 17,400 981 Proposed Intersection at SR 20...Alternative Traffic Volumes Alternative Year Average Speed White Point Road (mph) AADT VPH Receptor Max 1-Hr Conc (ppm) Max 8-Hr Conc (ppm

  17. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... 2006, and supervisory authorities in many other European countries have implemented similar regulation. Traffic light options are therefore likely to attract the attention of a wider audience of pension fund managers in the future. Focusing on the valuation of the traffic light option we set up a Black...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  18. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    2007-01-01

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... 2006, and supervisory authorities in many other European countries have implemented similar regulation. Traffic light options are therefore likely to attract the attention of a wider audience of pension fund managers in the future. Focusing on the valuation of the traffic light option we set up a Black...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  19. Analysis of a high speed train impact on a fuel transport flask

    International Nuclear Information System (INIS)

    Dowler, H.J.

    1983-05-01

    Current requirements for flask testing involve the recommended IAEA 9m drop test onto a flat unyielding surface. However, in practice impacts may occur at speeds far greater than the 30 mph equivalent of a 9m drop but into a yielding target. Additionally, the flask itself may be the target. This report investigates the postulated accident of a high speed train travelling at 125 mph impacting a stationary flask. The objectives of this report are to establish the forces that are involved and to put them into the context of the regulation drop tests, to investigate what effects the train as a whole has on the impact and to identify the significant parameters that determine the force level. A one dimensional model of the train is used to obtain the flask loading when the flask is both fixed and free, these giving the upper and lower bounds for all possible flask constraints. (author)

  20. Automated mixed traffic vehicle control and scheduling study

    Science.gov (United States)

    Peng, T. K. C.; Chon, K.

    1976-01-01

    The operation and the expected performance of a proposed automatic guideway transit system which uses low speed automated mixed traffic vehicles (AMTVs) were analyzed. Vehicle scheduling and headway control policies were evaluated with a transit system simulation model. The effect of mixed traffic interference on the average vehicle speed was examined with a vehicle pedestrian interface model. Control parameters regulating vehicle speed were evaluated for safe stopping and passenger comfort. Some preliminary data on the cost and operation of an experimental AMTV system are included. These data were the result of a separate task conducted at JPL, and were included as background information.

  1. Reducing the impact of speed dispersion on subway corridor flow.

    Science.gov (United States)

    Qiao, Jing; Sun, Lishan; Liu, Xiaoming; Rong, Jian

    2017-11-01

    The rapid increase in the volume of subway passengers in Beijing has necessitated higher requirements for the safety and efficiency of subway corridors. Speed dispersion is an important factor that affects safety and efficiency. This paper aims to analyze the management control methods for reducing pedestrian speed dispersion in subways. The characteristics of the speed dispersion of pedestrian flow were analyzed according to field videos. The control measurements which were conducted by placing traffic signs, yellow marking, and guardrail were proposed to alleviate speed dispersion. The results showed that the methods of placing traffic signs, yellow marking, and a guardrail improved safety and efficiency for all four volumes of pedestrian traffic flow, and the best-performing control measurement was guardrails. Furthermore, guardrails' optimal position and design measurements were explored. The research findings provide a rationale for subway managers in optimizing pedestrian traffic flow in subway corridors. Copyright © 2017. Published by Elsevier Ltd.

  2. Evaluation of diversion strategies in the context of advanced traffic management systems (ATMS) for an urban traffic corridor with heterogeneous traffic

    Energy Technology Data Exchange (ETDEWEB)

    Korlapati, D.R.

    2007-07-01

    Due to urbanization and accelerated growth in vehicular traffic, most big cities in India face problems related to traffic management resulting in severe congestion, pollution, and a high rate of accidents during peak hours. Lane blocking incidents on arterials or urban traffic corridors cause major disruption to traffic flow. Peak hour congestion with low average speeds and high accident rates are commonly associated with traffic in major cities in India. The situation is deteriorating further as creation of new facilities are almost impossible, with resource and space constraints. In such scenarios, application of advanced technologies seems to offer hope. One such application area is Advanced Traffic Management Systems (ATMS), a component of intelligent transportation system (ITS). Due to the unique traffic characteristics prevailing in India, the application of such systems needs to first be evaluated before implementation. This paper proposed a research methodology for the evaluation of diversion strategies in the context of ATMS for an urban corridor in India. The evaluation framework combined several relevant modules related to various aspects of traffic control, surveillance and advisory. As part of this study, a simulation model and a simulation optimization model were developed. The simulation model was microscopic in nature and captured the driver behaviour and traffic characteristics realistically by modeling the complex interactions among vehicles traversing a corridor. It was concluded that the results and observations were useful indicators to gauge the potential success of diversion plans. 10 refs., 1 tab., 2 figs.

  3. A Comparison of Traffic Operations among Beijing and Several International Megacities

    Directory of Open Access Journals (Sweden)

    Yuanzhou Yang

    2011-12-01

    Full Text Available High-Efficient traffic system is very important for economy and society of cities. Previous studies on the traffic comparison mostly took a city as a whole, but ignored the differences among areas inside the city. But in fact, the traffic congestion in different areas with a city is mostly different. Taking typical mega cities like Beijing, London, New York, and Tokyo as objects, this paper makes cross-comparison in the traffic operation and performance based on intelligent algorithm. Transportation infrastructure and travel demand data are discussed and unbalanced transport system is found in Beijing because of the conflict between too much traffic demand and defect road networks. From the aspects of traffic load, operational efficiency and safety, indexes including traffic v/c ratio, average vehicle speed and accident rate are selected to assess the performance of road traffic. It is concluded that road networks of Beijing have the worst performance compared with other three mega-cities and the primary reasons are the inappropriate distribution of utilization rate among the freeways, arterials, and local streets, and the high traffic concentration in urban area. So, several measures are recommended to improve the operation efficiency of traffic in Beijing especially for the green intelligent traffic system. Keywords: Traffic operation; Operational efficiency; Intelligent traffic system (ITS; Traffic load; traffic safety; Intelligent algorithm.

  4. Sensor for a traffic response system and traffic control system using a sensor

    NARCIS (Netherlands)

    Heijningen, A.W.P. van; Kleijweg, J.C.M.

    2007-01-01

    Traffic is sensed using a signal from a wave reflection detection device to classify road users into different types. Classification is performed dependent on statistical properties of reflections. Preferably reflections are resolved into reflections for different combinations of position and speed,

  5. [The utility of a continuous performance test embedded in virtual reality in measuring the effectiveness of MPH treatment in boys with ADHD].

    Science.gov (United States)

    Shriki, Liron; Weizer, Merav; Pollak, Yehuda; Weiss, Patricia L; Rizzo, Albert A; Gross-Tsur, Varda

    2010-01-01

    Continuous performance tasks (CPT) are popular in the diagnostic process of attention deficit hyperactivity disorder (ADHD), providing an objective measure of attention for a disorder with otherwise subjective criteria. The study aimed to: 1) examine whether the VR-CPT is sensitive to methylphenidate (MPH); 2) assess how the virtual reality (VR) environment is experienced. Twenty boys, 9-17 years, with ADHD underwent 3 CPTs: VR-CPT, the same CPT without VR (no VR-CPT) and the Test of Variables of Attention (T.O.V.A.). Subsequently, those with ADHD repeated the tests 1 hour following MPH ingestion. Immediately following the CPT, the subjects described their subjective experiences on the Short Feedback Questionnaire. Results were analyzed using ANOVA with repeated measures. MPH reduced the omission and commission errors on all tests to a similar degree. Subjective feelings of enjoyment were most positive for VR-CPT. The VR-CPT is a sensitive and user-friendly assessment tool for evaluating the effectiveness of MPH treatment in boys with ADHD.

  6. Towards a Cloud Based Smart Traffic Management Framework

    Science.gov (United States)

    Rahimi, M. M.; Hakimpour, F.

    2017-09-01

    Traffic big data has brought many opportunities for traffic management applications. However several challenges like heterogeneity, storage, management, processing and analysis of traffic big data may hinder their efficient and real-time applications. All these challenges call for well-adapted distributed framework for smart traffic management that can efficiently handle big traffic data integration, indexing, query processing, mining and analysis. In this paper, we present a novel, distributed, scalable and efficient framework for traffic management applications. The proposed cloud computing based framework can answer technical challenges for efficient and real-time storage, management, process and analyse of traffic big data. For evaluation of the framework, we have used OpenStreetMap (OSM) real trajectories and road network on a distributed environment. Our evaluation results indicate that speed of data importing to this framework exceeds 8000 records per second when the size of datasets is near to 5 million. We also evaluate performance of data retrieval in our proposed framework. The data retrieval speed exceeds 15000 records per second when the size of datasets is near to 5 million. We have also evaluated scalability and performance of our proposed framework using parallelisation of a critical pre-analysis in transportation applications. The results show that proposed framework achieves considerable performance and efficiency in traffic management applications.

  7. TOWARDS A CLOUD BASED SMART TRAFFIC MANAGEMENT FRAMEWORK

    Directory of Open Access Journals (Sweden)

    M. M. Rahimi

    2017-09-01

    Full Text Available Traffic big data has brought many opportunities for traffic management applications. However several challenges like heterogeneity, storage, management, processing and analysis of traffic big data may hinder their efficient and real-time applications. All these challenges call for well-adapted distributed framework for smart traffic management that can efficiently handle big traffic data integration, indexing, query processing, mining and analysis. In this paper, we present a novel, distributed, scalable and efficient framework for traffic management applications. The proposed cloud computing based framework can answer technical challenges for efficient and real-time storage, management, process and analyse of traffic big data. For evaluation of the framework, we have used OpenStreetMap (OSM real trajectories and road network on a distributed environment. Our evaluation results indicate that speed of data importing to this framework exceeds 8000 records per second when the size of datasets is near to 5 million. We also evaluate performance of data retrieval in our proposed framework. The data retrieval speed exceeds 15000 records per second when the size of datasets is near to 5 million. We have also evaluated scalability and performance of our proposed framework using parallelisation of a critical pre-analysis in transportation applications. The results show that proposed framework achieves considerable performance and efficiency in traffic management applications.

  8. Improved functionality, health related quality of life and decreased burden of disease in patients with ADHD treated with OROS® MPH: is treatment response different between children and adolescents?

    Directory of Open Access Journals (Sweden)

    Rettig Klaus

    2011-07-01

    Full Text Available Abstract Background To compare clinical and health-related quality of life (HRQoL outcomes between children and adolescents with ADHD treated with OROS® MPH, using data from two large similarly-designed multicenter, prospective, open-label, single-arm, non-interventional studies. Methods Pooled analysis (42603ATT4037, 42603 - ATT - 4001 including patients (6 to 18 years with a confirmed diagnosis of ADHD. Patients were treated with OROS® MPH for 12 weeks; ADHD symptoms, functioning, HRQoL, safety and tolerability parameters were assessed. Results 822 patients (583 children [6-12 years], 239 adolescents [13-18 years] were included in the pooled analysis. Mean daily OROS® MPH starting doses in the child and adolescent subgroups were 29.0 ± 11.7 and 37.6 ± 15.6 mg, respectively (p ® MPH in 76.9%, 86.0% and 79.3% of children, adolescents and the total population, respectively, at study end (p = 0.029 between-age subgroups. 195 of 822 patients (23.7% experienced at least one treatment-emergent adverse event; most commonly reported AEs in the total group (≥4% were insomnia (7.2%, anorexia (4.3% and involuntary muscle contractions (4.1%. No clinically relevant changes in body weight or vital signs were observed. Conclusions Clinically relevant differences between children and adolescents with ADHD are present. Adolescents appeared to have a lower health related quality of life and functioning compared to children at baseline, however, they were able to reach comparable ratings at endpoint for most items. Similarly, burden of disease decreased in patients and their carers. OROS MPH was generally safe and well tolerated.

  9. Delay-feedback control strategy for reducing CO2 emission of traffic flow system

    Science.gov (United States)

    Zhang, Li-Dong; Zhu, Wen-Xing

    2015-06-01

    To study the signal control strategy for reducing traffic emission theoretically, we first presented a kind of discrete traffic flow model with relative speed term based on traditional coupled map car-following model. In the model, the relative speed difference between two successive running cars is incorporated into following vehicle's acceleration running equation. Then we analyzed its stability condition with discrete control system stability theory. Third, we designed a delay-feedback controller to suppress traffic jam and decrease traffic emission based on modern controller theory. Last, numerical simulations are made to support our theoretical results, including the comparison of models' stability analysis, the influence of model type and signal control on CO2 emissions. The results show that the temporal behavior of our model is superior to other models, and the traffic signal controller has good effect on traffic jam suppression and traffic CO2 emission, which fully supports the theoretical conclusions.

  10. Performance of an Automated-Mixed-Traffic-Vehicle /AMTV/ System. [urban people mover

    Science.gov (United States)

    Peng, T. K. C.; Chon, K.

    1978-01-01

    This study analyzes the operation and evaluates the expected performance of a proposed automatic guideway transit system which uses low-speed Automated Mixed Traffic Vehicles (AMTV's). Vehicle scheduling and headway control policies are evaluated with a transit system simulation model. The effect of mixed-traffic interference on the average vehicle speed is examined with a vehicle-pedestrian interface model. Control parameters regulating vehicle speed are evaluated for safe stopping and passenger comfort.

  11. A apologia do consumo de bebidas alcoólicas e da velocidade no trânsito no Brasil: considerações sobre a propaganda de dois problemas de saúde pública The promotion of alcoholic beverage consumption and traffic speed in Brazil: considerations on the advertising of two public health problems

    Directory of Open Access Journals (Sweden)

    Ilana Pinsky

    2007-04-01

    Full Text Available Os acidentes de trânsito, muitas vezes relacionados com excesso de velocidade, e os problemas decorrentes do consumo de bebidas alcoólicas são dois importantes problemas de saúde pública no Brasil. Esses problemas podem estar associados, como no caso do dirigir alcoolizado, mas também se apresentam de maneira independente. Entre os diversos fatores que impactam nesses problemas encontra-se a propaganda de estímulo (comerciais. A influência da propaganda em várias questões de saúde, incluindo consumo de álcool e segurança no uso de veículos, tem um papel que recentemente está sendo mais estudado e compreendido. Setores públicos e privados no Brasil têm influência na regulamentação da propaganda, que é ainda principalmente exercida através do exercício da auto-regulamentação. O presente artigo apresenta um quadro geral sobre o assunto e, diante dos prejuízos de ordem social e econômica advindos do consumo de bebidas e dos acidentes, propõe-se a discutir o papel que vem sendo exercido pelos meios de comunicação, sua responsabilidade social e os limites da auto-regulamentação.Traffic accidents, which are often associated with speeding, and the problems associated with consumption of alcoholic beverages are two major public health concerns in Brazil. These problems may be associated, as in the case of drunk driving, but they also occur independently. Commercial advertising is one of the factors that have an impact on these issues. The influence of advertising on many health issues, including alcohol consumption and traffic safety plays a role that has been continuously investigated and understood. Public and private sectors in Brazil have an influence on the advertising regulation, which is still mainly performed by industry self-regulation. This paper presents a general framework on the subject. In addition, faced with the social and economic hazards resulting from alcohol consumption and traffic accidents, it

  12. Trajectory Based Traffic Analysis

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin

    2013-01-01

    We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point-and-click a......We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point......-and-click analysis, due to a novel and efficient indexing structure. With the web-site daisy.aau.dk/its/spqdemo/we will demonstrate several analyses, using a very large real-world data set consisting of 1.9 billion GPS records (1.5 million trajectories) recorded from more than 13000 vehicles, and touching most...

  13. Peer influence predicts speeding prevalence among teenage drivers.

    Science.gov (United States)

    Simons-Morton, Bruce G; Ouimet, Marie Claude; Chen, Rusan; Klauer, Sheila G; Lee, Suzanne E; Wang, Jing; Dingus, Thomas A

    2012-12-01

    Preventing speed-related crashes could reduce costs and improve efficiency in the transportation industry. This research examined the psychosocial and personality predictors of observed speeding among young drivers. Survey and driving data were collected from 42 newly-licensed teenage drivers during the first 18months of licensure. Speeding (i.e., driving 10mph over the speed limit; about 16km/h) was assessed by comparing speed data collected with recording systems installed in participants' vehicles with posted speed limits. Speeding was correlated with elevated g-force event rates (r=0.335, pb0.05), increased over time, and predicted by day vs. night trips, higher sensation seeking, substance use, tolerance of deviance, susceptibility to peer pressure, and number of risky friends. Perceived risk was a significant mediator of the association between speeding and risky friends. The findings support the contention that social norms may influence teenage speeding behavior and this relationship may operate through perceived risk. Copyright © 2012 National Safety Council and Elsevier Ltd. All rights reserved.

  14. Speed mathematics

    CERN Document Server

    Handley, Bill

    2012-01-01

    This new, revised edition of the bestselling Speed Mathematics features new chapters on memorising numbers and general information, calculating statistics and compound interest, square roots, logarithms and easy trig calculations. Written so anyone can understand, this book teaches simple strategies that will enable readers to make lightning-quick calculations. People who excel at mathematics use better strategies than the rest of us; they are not necessarily more intelligent. With Speed Mathematics you'll discover methods to make maths easy and fun. This book is perfect for stud

  15. Costs of traffic injuries

    DEFF Research Database (Denmark)

    Kruse, Marie

    2015-01-01

    assessed using Danish national healthcare registers. Productivity costs were computed using duration analysis (Cox regression models). In a subanalysis, cost per severe traffic injury was computed for the 12 995 individuals that experienced a severe injury. RESULTS: The socioeconomic cost of a traffic...... injury was €1406 (2009 price level) in the first year, and €8950 over a 10-year period. Per 100 000 population, the 10-year cost was €6 565 668. A severe traffic injury costs €4969 per person in the first year, and €4 006 685 per 100 000 population over a 10-year period. Victims of traffic injuries...

  16. Investigating Car Users’ Driving Behaviour through Speed Analysis

    Directory of Open Access Journals (Sweden)

    Laura Eboli

    2017-04-01

    Full Text Available Speed has been identified for a long time as a key risk factor in road traffic: inappropriate speeds contribute to a relevant part of traffic accidents. Many literature studies have focused on the relationship between speed and accident risk. Starting from this consideration this paper investigates traffic accident risk by analysing the travelling speeds recorded by real tests on the road. A survey was conducted to collect experimental speed values in a real context. A specific road segment, belonging to an Italian rural two-lane road, was repeatedly run by 27 drivers in order to collect the instantaneous speed values for each trajectory. Smartphone-equipped vehicles were used to record continuous speed data. The recorded data were used to calculate: the average speed, 50th and 85th percentile speed for each geometric element of the analysed road segment. The main result of the research is the classification of car users’ driving behaviour based on the speed values. By using the above mentioned ranges of speed, the classification provides three types of driving behaviour: safe, unsafe, and safe but potentially dangerous. It was found that only four drivers feature “safe” behaviour, driving in a safe manner on most of the road elements. However, the major part of drivers, even if they feature safe behaviour, could be dangerous for other drivers because they drive at very low speeds.

  17. Criterion for traffic phases in single vehicle data and empirical test of a microscopic three-phase traffic theory

    International Nuclear Information System (INIS)

    Kerner, Boris S; Klenov, Sergey L; Hiller, Andreas

    2006-01-01

    Based on empirical and numerical microscopic analyses, the physical nature of a qualitatively different behaviour of the wide moving jam phase in comparison with the synchronized flow phase-microscopic traffic flow interruption within the wide moving jam phase-is found. A microscopic criterion for distinguishing the synchronized flow and wide moving jam phases in single vehicle data measured at a single freeway location is presented. Based on this criterion, empirical microscopic classification of different local congested traffic states is performed. Simulations made show that the microscopic criterion and macroscopic spatiotemporal objective criteria lead to the same identification of the synchronized flow and wide moving jam phases in congested traffic. Microscopic models in the context of three-phase traffic theory have been tested based on the microscopic criterion for the phases in congested traffic. It is found that microscopic three-phase traffic models can explain both microscopic and macroscopic empirical congested pattern features. It is obtained that microscopic frequency distributions for vehicle speed difference as well as fundamental diagrams and speed correlation functions can depend on the spatial co-ordinate considerably. It turns out that microscopic optimal velocity (OV) functions and time headway distributions are not necessarily qualitatively different, even if local congested traffic states are qualitatively different. The reason for this is that important spatiotemporal features of congested traffic patterns are lost in these as well as in many other macroscopic and microscopic traffic characteristics, which are widely used as the empirical basis for a test of traffic flow models, specifically, cellular automata traffic flow models

  18. MODELLING OF DYNAMIC SPEED LIMITS USING THE MODEL PREDICTIVE CONTROL

    Directory of Open Access Journals (Sweden)

    Andrey Borisovich Nikolaev

    2017-09-01

    Full Text Available The article considers the issues of traffic management using intelligent system “Car-Road” (IVHS, which consist of interacting intelligent vehicles (IV and intelligent roadside controllers. Vehicles are organized in convoy with small distances between them. All vehicles are assumed to be fully automated (throttle control, braking, steering. Proposed approaches for determining speed limits for traffic cars on the motorway using a model predictive control (MPC. The article proposes an approach to dynamic speed limit to minimize the downtime of vehicles in traffic.

  19. Trajectories for Novel and Detailed Traffic Information

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Torp, Kristian

    2012-01-01

    the central metric free-flow speed from trajectories, instead of using point-based measurements such as induction-loops. This free-flow speed is widely used to compute and monitor the congestion level. The paper argues that the actual travel-time is a more accurate metric. The paper suggests a novel approach...... are correctly coordinated, and navigational device manufacturers to advice drivers in real-time on expected behavior of signalized intersections. The main conclusion is that trajectories can provide novel insight into the actual traffic situation that is not possible using existing approaches. Further...... to analyzing individual intersections that enables traffic analysts to compute queue lengths and estimated time to pass an intersection. Finally, the paper uses associative rule mining for evaluating green waves on road stretches. Such information can be used to verify that signalized intersections...

  20. Traffic Flow Visualization and Control

    National Research Council Canada - National Science Library

    Larson, Robert

    1999-01-01

    .... Air Force Research Laboratory. It is a video-camera-based, wide-area, traffic surveillance and detection system that provides real-time traffic information to traffic management center operators...

  1. Pedestrian Friendly Traffic Signal Control.

    Science.gov (United States)

    2016-01-01

    This project continues research aimed at real-time detection and use of pedestrian : traffic flow information to enhance adaptive traffic signal control in urban areas : where pedestrian traffic is substantial and must be given appropriate attention ...

  2. The design of traffic signal coordinated control

    Science.gov (United States)

    Guo, Xueting; Sun, Hongsheng; Wang, Xifu

    2017-05-01

    Traffic as the tertiary industry is an important pillar industry to support the normal development of the economy. But now China's road traffic development and economic development has shown a great imbalance and fault phenomenon, which greatly inhibited the normal development of China's economy. Now in many large and medium-sized cities in China are implementing green belt construction. The so-called green band is when the road conditions to meet the conditions for the establishment of the green band, the sections of the intersection of several planning to a traffic coordination control system, so that when the driver at a specific speed can be achieved without stopping the continuous Through the intersection. Green belt can effectively reduce the delay and queuing length of vehicle driving, the normal function of urban roads and reduce the economic losses caused by traffic congestion is a great help. In this paper, the theoretical basis of the design of the coordinated control system is described. Secondly, the green time offset is calculated by the analytic method and the green band is established. And then the VISSIM software is used to simulate the traffic system before and after the improvement. Finally, the results of the two simulations are compared.

  3. Analysis of traffic accidents in Romania, 2009.

    Science.gov (United States)

    Călinoiu, Geovana; Minca, Dana Galieta; Furtunescu, Florentina Ligia

    2012-01-01

    This paper aimed to underline the main consequences of traffic accidents in Romania 2009 and their associated causes or circumstances. We identified some problematic geographic areas, some critical months or moments of the day and also the most frequent causes; all these should become targets for the future planning. The current analysis provides some priority criteria for public health interventions. So, the future national road safety strategy should be in line with the EU objectives, but also with the national priorities. Romania is far away from the average EU target for 2010 of halving the death by traffic accidents registered in 2001. To describe the circumstances and the consequences related to traffic accidents registered in Romania, for the year 2009. An ecological study was conducted. The traffic accidents circumstances were analyzed in terms of magnitude, geographic space, time and cause. The consequences were analyzed as affected people and damaged cars. A total of 28,627 traffic accidents were registered in Romania during the year 2009. 2,796 people were killed and 27,968 were hospitalized and 42,443 cars were damaged. 3 of 4 accidents were caused by violations on behalf of the car drivers. Most common violations in car drivers were excess of speed and priority violations (52.4%). Among the pedestrians, 7 of 10 accidents were caused by illegal crossing. A higher number of accidents occurred during the summer months and during the evening hours (from 5.00 pm till 8.00 pm). The traffic accidents represent a real public health problem in Romania and a serious burden for the health system. The gap between Romania and the other EU member states needs to be diminished in the next decade. In this purpose, the future national road safety strategy should be in line with the EU objectives, but also with the national priorities. Research is needed to understand the causes and the socio-economical impact of traffic accidents and to define appropriate national

  4. Spatiotemporal Recurrent Convolutional Networks for Traffic Prediction in Transportation Networks.

    Science.gov (United States)

    Yu, Haiyang; Wu, Zhihai; Wang, Shuqin; Wang, Yunpeng; Ma, Xiaolei

    2017-06-26

    Predicting large-scale transportation network traffic has become an important and challenging topic in recent decades. Inspired by the domain knowledge of motion prediction, in which the future motion of an object can be predicted based on previous scenes, we propose a network grid representation method that can retain the fine-scale structure of a transportation network. Network-wide traffic speeds are converted into a series of static images and input into a novel deep architecture, namely, spatiotemporal recurrent convolutional networks (SRCNs), for traffic forecasting. The proposed SRCNs inherit the advantages of deep convolutional neural networks (DCNNs) and long short-term memory (LSTM) neural networks. The spatial dependencies of network-wide traffic can be captured by DCNNs, and the temporal dynamics can be learned by LSTMs. An experiment on a Beijing transportation network with 278 links demonstrates that SRCNs outperform other deep learning-based algorithms in both short-term and long-term traffic prediction.

  5. Potential for in-car speed assistance systems : results of a large-scale survey in Belgium and the Netherlands

    NARCIS (Netherlands)

    Vlassenroot, S.; Marchau, V.; De Mol, J.; Brookhuis, K.; Witlox, F.

    Speeding is generally considered to be a major cause of road traffic accidents. In-car speed assistance systems aim at reducing speeding. Several trials with different types of in-car speed assistance systems, in particular intelligent speed assistance (ISA), have shown that ISA can be an effective

  6. Effects of main actor, outcome and affect on biased braking speed judgments

    Directory of Open Access Journals (Sweden)

    Ola Svenson

    2012-05-01

    Full Text Available Subjects who judged speed in a driving scenario overestimated how fast they could decelerate when speeding compared to when keeping within the speed limit (Svenson, 2009. The purpose of the present studies were to replicate studies conducted in Europe with subjects in the U.S., to study the influence of speed unit (kph vs. mph, affective reactions to outcome (collision and identity of main actor (driver on braking speed judgments. The results replicated the European findings and the outcome affective factor (passing a line/killing a child and the actor factor (subject/driver in general had significant effects on judgments of braking speed. The results were related to psychological theory and applied implications were discussed.

  7. Controlled Traffic Farming

    OpenAIRE

    Controlled Traffic Farming Europe

    2011-01-01

    Metadata only record Controlled Traffic Farming (CTF) is a farming method used to reduce soil compaction, decrease inputs, and improve soil structure when coupled with reduced-till or no-till practices. This practices utilizes permanent traffic/wheel zones to limit soil compaction to a specific area. This website provides practical information on CTF, case studies, workshops, and links to additional resources.

  8. Visualization of Traffic Accidents

    Science.gov (United States)

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  9. Road Traffic in China

    NARCIS (Netherlands)

    Jie, L.; Van Zuylen, H.J.

    2014-01-01

    Traffic is tightly related to the social and economic development in a country. In China the development of the economy has been very fast in the past 30 years and this is still continuing. The transport infrastructure shows a similar pattern, while traffic is also rapidly growing. In urban areas

  10. Properties of Traffic Risk Coefficient

    Science.gov (United States)

    Tang, Tie-Qiao; Huang, Hai-Jun; Shang, Hua-Yan; Xue, Yu

    2009-10-01

    We use the model with the consideration of the traffic interruption probability (Physica A 387(2008)6845) to study the relationship between the traffic risk coefficient and the traffic interruption probability. The analytical and numerical results show that the traffic interruption probability will reduce the traffic risk coefficient and that the reduction is related to the density, which shows that this model can improve traffic security.

  11. Traffic dynamics on coupled spatial networks

    International Nuclear Information System (INIS)

    Du, Wen-Bo; Zhou, Xing-Lian; Chen, Zhen; Cai, Kai-Quan; Cao, Xian-Bin

    2014-01-01

    With the rapid development of modern traffic, various means of transportation systems make it more convenient and diversified for passengers to travel out. In this paper, we establish a two-layered spatial network model where the low-speed lower layer is a regular lattice and the high-speed upper layer is a scale-free network embedded in the lattice. Passengers will travel along the path with the minimal travel time, and they can transfer from one layer to the other, which will induce extra transfer cost. We extensively investigate the traffic process on these coupled spatial networks and focus on the effect of the parameter α, the speed ratio between two networks. It is found that, as α grows, the network capacity of the coupled networks increases in the early stage and then decreases, indicating that cooperation between the coupled networks will induce the highest network capacity at an optimal α. We then provide an explanation for this non-monotonous dependence from a micro-scope point of view. The travel time reliability is also examined. Both in free-flow state and congestion state, the travel time is linearly related to the Euclidean distance. However, the variance of travel time in the congestion state is remarkably larger than that in the free-flow state, namely, people have to set aside more redundant time in an unreliable traffic system

  12. Impacts of Snowy Weather Conditions on Expressway Traffic Flow Characteristics

    Directory of Open Access Journals (Sweden)

    Jiancheng Weng

    2013-01-01

    Full Text Available Snowy weather will significantly degrade expressway operations, reduce service levels, and increase driving difficulty. Furthermore, the impact of snow varies in different types of roads, diverse cities, and snow densities due to different driving behavior. Traffic flow parameters are essential to decide what should be appropriate for weather-related traffic management and control strategies. This paper takes Beijing as a case study and analyzes traffic flow data collected by detectors in expressways. By comparing the performance of traffic flow under normal and snowy weather conditions, this paper quantitatively describes the impact of adverse weather on expressway volume and average speeds. Results indicate that average speeds on the Beijing expressway under heavy snow conditions decrease by 10–20 km/h when compared to those under normal weather conditions, the vehicle headway generally increases by 2–4 seconds, and the road capacity drops by about 33%. This paper also develops a specific expressway traffic parameter reduction model which proposes reduction coefficients of expressway volumes and speeds under various snow density conditions in Beijing. The conclusions paper provide effective foundational parameters for urban expressway controls and traffic management under snow conditions.

  13. Cellular automata model for traffic flow at intersections in internet of vehicles

    Science.gov (United States)

    Zhao, Han-Tao; Liu, Xin-Ru; Chen, Xiao-Xu; Lu, Jian-Cheng

    2018-03-01

    Considering the effect of the front vehicle's speed, the influence of the brake light and the conflict of the traffic flow, we established a cellular automata model called CE-NS for traffic flow at the intersection in the non-vehicle networking environment. According to the information interaction of Internet of Vehicles (IoV), introducing parameters describing the congestion and the accurate speed of the front vehicle into the CE-NS model, we improved the rules of acceleration, deceleration and conflict, and finally established a cellular automata model for traffic flow at intersections of IoV. The relationship between traffic parameters such as vehicle speed, flow and average travel time is obtained by numerical simulation of two models. Based on this, we compared the traffic situation of the non-vehicle networking environment with conditions of IoV environment, and analyzed the influence of the different degree of IoV on the traffic flow. The results show that the traffic speed is increased, the travel time is reduced, the flux of intersections is increased and the traffic flow is more smoothly under IoV environment. After the vehicle which achieves IoV reaches a certain proportion, the operation effect of the traffic flow begins to improve obviously.

  14. Matching Countermeasures to Driver Types and Speeding Behavior

    Science.gov (United States)

    2017-12-01

    Speeding is a common contributing factor in fatal traffic crashes. Attempts to address this problem through a variety of approaches have, so far, not led to a substantial reduction in speeding-related fatalities. An address-based mail survey of licen...

  15. Urban Traffic Signal System Control Structural Optimization Based on Network Analysis

    Directory of Open Access Journals (Sweden)

    Li Wang

    2013-01-01

    Full Text Available Advanced urban traffic signal control systems such as SCOOT and SCATS normally coordinate traffic network using multilevel hierarchical control mechanism. In this mechanism, several key intersections will be selected from traffic signal network and the network will be divided into different control subareas. Traditionally, key intersection selection and control subareas division are executed according to dynamic traffic counts and link length between intersections, which largely rely on traffic engineers’ experience. However, it omits important inherent characteristics of traffic network topology. In this paper, we will apply network analysis approach into these two aspects for traffic system control structure optimization. Firstly, the modified C-means clustering algorithm will be proposed to assess the importance of intersections in traffic network and furthermore determine the key intersections based on three indexes instead of merely on traffic counts in traditional methods. Secondly, the improved network community discovery method will be used to give more reasonable evidence in traffic control subarea division. Finally, to test the effectiveness of network analysis approach, a hardware-in-loop simulation environment composed of regional traffic control system, microsimulation software and signal controller hardware, will be built. Both traditional method and proposed approach will be implemented on simulation test bed to evaluate traffic operation performance indexes, for example, travel time, stop times, delay and average vehicle speed. Simulation results show that the proposed network analysis approach can improve the traffic control system operation performance effectively.

  16. VBR video traffic models

    CERN Document Server

    Tanwir, Savera

    2014-01-01

    There has been a phenomenal growth in video applications over the past few years. An accurate traffic model of Variable Bit Rate (VBR) video is necessary for performance evaluation of a network design and for generating synthetic traffic that can be used for benchmarking a network. A large number of models for VBR video traffic have been proposed in the literature for different types of video in the past 20 years. Here, the authors have classified and surveyed these models and have also evaluated the models for H.264 AVC and MVC encoded video and discussed their findings.

  17. Road Traffic Injuries

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-guo

    2005-01-01

    @@ As everybody knows that automobiles have been greatly changing our life. However, everything has two sides, motor vehicles have also caused a huge number of people's deaths, injuries and property damage. Traffic crashes are perhaps the number one public health problem in developed countries [1]. In the United States, pre-retirement years of life lost in traffic crashes are more than that of the two combined leading diseases: cancer and heart disease [1]. Today road traffic crash (RTC) ranks 11th in leading cause of death and accounts for 2.1% of all deaths globally.

  18. Monitoring Traffic Information with a Developed Acceleration Sensing Node

    Directory of Open Access Journals (Sweden)

    Zhoujing Ye

    2017-12-01

    Full Text Available In this paper, an acceleration sensing node for pavement vibration was developed to monitor traffic information, including vehicle speed, vehicle types, and traffic flow, where a hardware design with low energy consumption and node encapsulation could be accomplished. The service performance of the sensing node was evaluated, by methods including waterproof test, compression test, sensing performance analysis, and comparison test. The results demonstrate that the sensing node is low in energy consumption, high in strength, IPX8 waterproof, and high in sensitivity and resolution. These characteristics can be applied to practical road environments. Two sensing nodes were spaced apart in the direction of travelling. In the experiment, three types of vehicles passed by the monitoring points at several different speeds and values of d (the distance between the sensor and the nearest tire center line. Based on cross-correlation with kernel pre-smoothing, a calculation method was applied to process the raw data. New algorithms for traffic flow, speed, and axle length were proposed. Finally, the effects of vehicle speed, vehicle weight, and d value on acceleration amplitude were statistically evaluated. It was found that the acceleration sensing node can be used for traffic flow, vehicle speed, and other types of monitoring.

  19. Monitoring Traffic Information with a Developed Acceleration Sensing Node.

    Science.gov (United States)

    Ye, Zhoujing; Wang, Linbing; Xu, Wen; Gao, Zhifei; Yan, Guannan

    2017-12-05

    In this paper, an acceleration sensing node for pavement vibration was developed to monitor traffic information, including vehicle speed, vehicle types, and traffic flow, where a hardware design with low energy consumption and node encapsulation could be accomplished. The service performance of the sensing node was evaluated, by methods including waterproof test, compression test, sensing performance analysis, and comparison test. The results demonstrate that the sensing node is low in energy consumption, high in strength, IPX8 waterproof, and high in sensitivity and resolution. These characteristics can be applied to practical road environments. Two sensing nodes were spaced apart in the direction of travelling. In the experiment, three types of vehicles passed by the monitoring points at several different speeds and values of d (the distance between the sensor and the nearest tire center line). Based on cross-correlation with kernel pre-smoothing, a calculation method was applied to process the raw data. New algorithms for traffic flow, speed, and axle length were proposed. Finally, the effects of vehicle speed, vehicle weight, and d value on acceleration amplitude were statistically evaluated. It was found that the acceleration sensing node can be used for traffic flow, vehicle speed, and other types of monitoring.

  20. Rail-induced Traffic in China

    Directory of Open Access Journals (Sweden)

    Nan He

    2017-11-01

    Full Text Available The rapid development of China’s railway has exerted an enormous influence on the intercity passenger transport structure in recent years. However, it has not satisfied the passengers’ travel demand due to induced traffic. This paper is committed to solving such issue, with the aim of satisfying the current travel demand, and of anticipating the demand of the predicted traffic growth over the next 20 to 30 years. The paper has considered the increase in rail passenger kilometres caused by the growth of rail kilometres as rail-induced traffic. Based on the concept and former research of induced traffic, the panel data of 26 provinces and 3 municipalities of China between the year 2000 and 2014 were collected, and the elasticity models (including elasticity-based model, distributed lag model, high-speed rail (HSR elasticity model and rail efficiency model have been constructed. The results show the importance of model formation incorporation of rail-induced traffic. It is better to get the correct value in divided zones with different train frequencies or incorporation rail efficiency in cities or provinces. The lag time and rail types also need to be considered. In summary, the results analysis not only confirms the existence of rail-induced traffic, but also provides substantial recommendations to train operation planning.

  1. Bayes classifiers for imbalanced traffic accidents datasets.

    Science.gov (United States)

    Mujalli, Randa Oqab; López, Griselda; Garach, Laura

    2016-03-01

    Traffic accidents data sets are usually imbalanced, where the number of instances classified under the killed or severe injuries class (minority) is much lower than those classified under the slight injuries class (majority). This, however, supposes a challenging problem for classification algorithms and may cause obtaining a model that well cover the slight injuries instances whereas the killed or severe injuries instances are misclassified frequently. Based on traffic accidents data collected on urban and suburban roads in Jordan for three years (2009-2011); three different data balancing techniques were used: under-sampling which removes some instances of the majority class, oversampling which creates new instances of the minority class and a mix technique that combines both. In addition, different Bayes classifiers were compared for the different imbalanced and balanced data sets: Averaged One-Dependence Estimators, Weightily Average One-Dependence Estimators, and Bayesian networks in order to identify factors that affect the severity of an accident. The results indicated that using the balanced data sets, especially those created using oversampling techniques, with Bayesian networks improved classifying a traffic accident according to its severity and reduced the misclassification of killed and severe injuries instances. On the other hand, the following variables were found to contribute to the occurrence of a killed causality or a severe injury in a traffic accident: number of vehicles involved, accident pattern, number of directions, accident type, lighting, surface condition, and speed limit. This work, to the knowledge of the authors, is the first that aims at analyzing historical data records for traffic accidents occurring in Jordan and the first to apply balancing techniques to analyze injury severity of traffic accidents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Pedestrian Safety in Road Traffic in Poland

    Science.gov (United States)

    Budzynski, Marcin; Jamroz, Kazimierz; Mackun, Tomasz

    2017-10-01

    Every third road accident in Poland involves a pedestrian as a participant or, most of the time, a casualty. Pedestrian accidents are usually the result of complex situations and the outcome of a number of factors related to driver and pedestrian behaviour and road infrastructure. Safety depends largely on how well the traffic condition is perceived and on visibility in traffic. The paper presents the results of analyses of methodologies for systematic studies of pedestrian behaviour and pedestrian-driver relations. The effects of the location of the site, type of cross-section and other selected parameters on pedestrian and driver behaviour are demonstrated. The analyses showed that pedestrians are most often put at risk by too long pedestrian crossings, vehicles going too fast around pedestrian crossings, lack of proper sight distance and poorly lit or unlit pedestrian crossings. The reason for such defective infrastructure is that planners, designers, contractors and maintenance services are not receiving any support from design, marking and maintenance regulations for pedestrian traffic. In addition, the Road Traffic Law is not restrictive enough when it comes to drivers’ obligations towards pedestrian safety. Polish design regulations allow long pedestrian crossings up to four lanes in one direction or three lanes in two directions irrespective of traffic control and speed limits. Pedestrian crossings should be kept at a maximum of three lanes. There is nothing in the design regulations about the required driver-pedestrian sight distance. Neither does the Road Traffic Law help engineers with that. It is legal to park vehicles within 10 m of a pedestrian crossing which does not guarantee the necessary sight distance. Drivers must be able to see a pedestrian waiting or stepping onto the crossing from a distance that will help them come to a stop safely. It is safer to follow the principle of providing adequate pedestrian sight distance. Recommendations for

  3. Driver behavior in traffic.

    Science.gov (United States)

    2012-02-01

    Existing traffic analysis and management tools do not model the ability of drivers to recognize their environment and respond to it with behaviors that vary according to the encountered driving situation. The small body of literature on characterizin...

  4. Penalties in traffic.

    NARCIS (Netherlands)

    2009-01-01

    Traffic offenders are penalized in various ways: fines, (temporary) driving licence suspensions, confiscation of their vehicles, penalty points, mandatory participation in rehabilitation programmes, prison sentences or community service. The aim of penalties is to punish offenders, to protect

  5. Non-Traffic Citations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Non-traffic citations (NTCs, also known as "summary offenses") document low-level criminal offenses where a law enforcement officer or other authorized official...

  6. Allegheny County Traffic Counts

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Traffic sensors at over 1,200 locations in Allegheny County collect vehicle counts for the Pennsylvania Department of Transportation. Data included in the Health...

  7. Traffic Signal Cycle Lengths

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — Traffic signal location list for the town of Chapel Hill. This data set includes light cycle information as well as as intersection information.The Town of Chapel...

  8. The design of high-speed windmills suitable for driving electric generators

    Energy Technology Data Exchange (ETDEWEB)

    Klein, G J

    1975-01-01

    A simple windmill theory is presented for designing a small, horizontal axis windmill for powering an automobile-type generator used along with a storage battery. Windmills designed by the method presented in this paper have maximum efficiencies in the order of 0.40 to 0.45, which approaches 75% of the theoretical maximum. Wind tunnel tests were performed on a two-bladed unit designed for a tip speed/wind speed ratio of 7. Maximum efficiency was close to 0.45 at a tip speed/wind speed ratio of slightly over 6. This windmill, if fitted directly to a specially wound three-brush automobile type generator, wil begin to charge a 6-volt battery at a wind speed of 7.5-8 mph. 2 refs., 7 figs., 1 tab.

  9. Planning for active traffic management in Virginia : international best practices and implementation strategies.

    Science.gov (United States)

    2012-10-01

    Active Traffic Management (ATM) applications, such as variable speed limits, queue warning systems, and dynamic : ramp metering, have been shown to offer mobility and safety benefits. Yet because they differ from conventional capacity : investments i...

  10. Intelligent vehicle based traffic monitoring – exploring application in South Africa

    CSIR Research Space (South Africa)

    Labuschagne, FJJ

    2010-08-01

    Full Text Available The paper details the anticipated benefits of an intelligent vehicle based traffic monitoring approach holds. The approach utilises advanced technology with the potential to reduce crashes and includes the monitor of vehicle speeds and flows...

  11. Investigation of the Link Between Macroscopic Traffic Flow Characteristics and Individual Vehicle Fuel Consumption

    Science.gov (United States)

    2017-10-01

    This project investigated the factors impacting individual vehicle energy consumption, including vehicle characteristics, ambient temperature, season, speed, driving behavior, and traffic flow. A fleet of 18 vehicles with a variety of ownership, size...

  12. Environmentally friendly traffic management system using integrated road-vehicle system

    NARCIS (Netherlands)

    Mahmod, M.M.; Arem, B. van

    2008-01-01

    Local habitability is coming under increasing pressure from harmful traffic emissions. This emission is strongly correlated to the characteristics and dynamics of traffic: type of vehicle, speed, acceleration and deceleration. This paper investigates the use of integrated road-vehicle systems for

  13. Development of active traffic management strategies for Minnesota freeway corridors : final report.

    Science.gov (United States)

    2015-06-01

    In this study, the effectiveness of the I-35W variable advisory speed limit system on the improvement of the traffic : flow was evaluated with the real traffic data. The analysis results indicate there was significant reduction in the : average maxim...

  14. Simulation of three lanes one-way freeway in low visibility weather by possible traffic accidents

    Science.gov (United States)

    Pang, Ming-bao; Zheng, Sha-sha; Cai, Zhang-hui

    2015-09-01

    The aim of this work is to investigate the traffic impact of low visibility weather on a freeway including the fraction of real vehicle rear-end accidents and road traffic capacity. Based on symmetric two-lane Nagel-Schreckenberg (STNS) model, a cellular automaton model of three-lane freeway mainline with the real occurrence of rear-end accidents in low visibility weather, which considers delayed reaction time and deceleration restriction, was established with access to real-time traffic information of intelligent transportation system (ITS). The characteristics of traffic flow in different visibility weather were discussed via the simulation experiments. The results indicate that incoming flow control (decreasing upstream traffic volume) and inputting variable speed limits (VSL) signal are effective in accident reducing and road actual traffic volume's enhancing. According to different visibility and traffic demand the appropriate control strategies should be adopted in order to not only decrease the probability of vehicle accidents but also avoid congestion.

  15. Fine-granularity inference and estimations to network traffic for SDN.

    Directory of Open Access Journals (Sweden)

    Dingde Jiang

    Full Text Available An end-to-end network traffic matrix is significantly helpful for network management and for Software Defined Networks (SDN. However, the end-to-end network traffic matrix's inferences and estimations are a challenging problem. Moreover, attaining the traffic matrix in high-speed networks for SDN is a prohibitive challenge. This paper investigates how to estimate and recover the end-to-end network traffic matrix in fine time granularity from the sampled traffic traces, which is a hard inverse problem. Different from previous methods, the fractal interpolation is used to reconstruct the finer-granularity network traffic. Then, the cubic spline interpolation method is used to obtain the smooth reconstruction values. To attain an accurate the end-to-end network traffic in fine time granularity, we perform a weighted-geometric-average process for two interpolation results that are obtained. The simulation results show that our approaches are feasible and effective.

  16. Fine-granularity inference and estimations to network traffic for SDN.

    Science.gov (United States)

    Jiang, Dingde; Huo, Liuwei; Li, Ya

    2018-01-01

    An end-to-end network traffic matrix is significantly helpful for network management and for Software Defined Networks (SDN). However, the end-to-end network traffic matrix's inferences and estimations are a challenging problem. Moreover, attaining the traffic matrix in high-speed networks for SDN is a prohibitive challenge. This paper investigates how to estimate and recover the end-to-end network traffic matrix in fine time granularity from the sampled traffic traces, which is a hard inverse problem. Different from previous methods, the fractal interpolation is used to reconstruct the finer-granularity network traffic. Then, the cubic spline interpolation method is used to obtain the smooth reconstruction values. To attain an accurate the end-to-end network traffic in fine time granularity, we perform a weighted-geometric-average process for two interpolation results that are obtained. The simulation results show that our approaches are feasible and effective.

  17. Integration of Weather Avoidance and Traffic Separation

    Science.gov (United States)

    Consiglio, Maria C.; Chamberlain, James P.; Wilson, Sara R.

    2011-01-01

    This paper describes a dynamic convective weather avoidance concept that compensates for weather motion uncertainties; the integration of this weather avoidance concept into a prototype 4-D trajectory-based Airborne Separation Assurance System (ASAS) application; and test results from a batch (non-piloted) simulation of the integrated application with high traffic densities and a dynamic convective weather model. The weather model can simulate a number of pseudo-random hazardous weather patterns, such as slow- or fast-moving cells and opening or closing weather gaps, and also allows for modeling of onboard weather radar limitations in range and azimuth. The weather avoidance concept employs nested "core" and "avoid" polygons around convective weather cells, and the simulations assess the effectiveness of various avoid polygon sizes in the presence of different weather patterns, using traffic scenarios representing approximately two times the current traffic density in en-route airspace. Results from the simulation experiment show that the weather avoidance concept is effective over a wide range of weather patterns and cell speeds. Avoid polygons that are only 2-3 miles larger than their core polygons are sufficient to account for weather uncertainties in almost all cases, and traffic separation performance does not appear to degrade with the addition of weather polygon avoidance. Additional "lessons learned" from the batch simulation study are discussed in the paper, along with insights for improving the weather avoidance concept. Introduction

  18. Traffic simulation based ship collision probability modeling

    Energy Technology Data Exchange (ETDEWEB)

    Goerlandt, Floris, E-mail: floris.goerlandt@tkk.f [Aalto University, School of Science and Technology, Department of Applied Mechanics, Marine Technology, P.O. Box 15300, FI-00076 AALTO, Espoo (Finland); Kujala, Pentti [Aalto University, School of Science and Technology, Department of Applied Mechanics, Marine Technology, P.O. Box 15300, FI-00076 AALTO, Espoo (Finland)

    2011-01-15

    Maritime traffic poses various risks in terms of human, environmental and economic loss. In a risk analysis of ship collisions, it is important to get a reasonable estimate for the probability of such accidents and the consequences they lead to. In this paper, a method is proposed to assess the probability of vessels colliding with each other. The method is capable of determining the expected number of accidents, the locations where and the time when they are most likely to occur, while providing input for models concerned with the expected consequences. At the basis of the collision detection algorithm lays an extensive time domain micro-simulation of vessel traffic in the given area. The Monte Carlo simulation technique is applied to obtain a meaningful prediction of the relevant factors of the collision events. Data obtained through the Automatic Identification System is analyzed in detail to obtain realistic input data for the traffic simulation: traffic routes, the number of vessels on each route, the ship departure times, main dimensions and sailing speed. The results obtained by the proposed method for the studied case of the Gulf of Finland are presented, showing reasonable agreement with registered accident and near-miss data.

  19. Identification of Risk Factors Influencing Road Traffic Accidents

    Directory of Open Access Journals (Sweden)

    M. Touahmia

    2018-02-01

    Full Text Available Road traffic accidents (RTAs are becoming a major problem around the world, incurring enormous losses of human and economic resources. Recent reports from the World Health Organization (WHO reveal that each year more than 1.25 million people are killed and 50 million are injured in road traffic accidents worldwide. In Saudi Arabia, statistics show that at least one traffic accident occurs every minute, causing up to 7,000 deaths and over 39,000 injuries annually. In this study, the main causes of RATs in the province of Hail are examined. The data was collected through the use of a survey which was developed to evaluate the effect of influencing parameters on RTA rate. The results show that 67% of RTAs result from human factors, 29% from road conditions and 4% from vehicle defects. Excessive speed and violation of traffic rules and regulations were found to be the main causes of RATs. Low rates of compliance with speed limit signs and seat-belt regulations were also observed. These findings highlight the need of strengthening effective traffic law enforcement alongside with improving traffic safety and raising public awareness.

  20. Speed Choice and Curve Radius on Rural Roads

    DEFF Research Database (Denmark)

    Rimme, Nicolai; Nielsen, Lea; Kjems, Erik

    2016-01-01

    with informative speed-calming measures as traffic signs, reflectors or surface painting. However, it has been the hypothesis that people are reducing their speed insufficiently and are driving too fast in most curved alignments – especially when they are driving there frequently. By knowing the speed near...... and in the curved alignments compared to the geometry of the curved alignments, it can be clarified, if and which speed-calming measures that are required. Using GNSS-based floating car data (FCD) from driving cars the speed near and in curved alignments is found. Single observation of FCD are connected to trips...

  1. Traffic Management as a Service: The Traffic Flow Pattern Classification Problem

    Directory of Open Access Journals (Sweden)

    Carlos T. Calafate

    2015-01-01

    Full Text Available Intelligent Transportation System (ITS technologies can be implemented to reduce both fuel consumption and the associated emission of greenhouse gases. However, such systems require intelligent and effective route planning solutions to reduce travel time and promote stable traveling speeds. To achieve such goal these systems should account for both estimated and real-time traffic congestion states, but obtaining reliable traffic congestion estimations for all the streets/avenues in a city for the different times of the day, for every day in a year, is a complex task. Modeling such a tremendous amount of data can be time-consuming and, additionally, centralized computation of optimal routes based on such time-dependencies has very high data processing requirements. In this paper we approach this problem through a heuristic to considerably reduce the modeling effort while maintaining the benefits of time-dependent traffic congestion modeling. In particular, we propose grouping streets by taking into account real traces describing the daily traffic pattern. The effectiveness of this heuristic is assessed for the city of Valencia, Spain, and the results obtained show that it is possible to reduce the required number of daily traffic flow patterns by a factor of 4210 while maintaining the essence of time-dependent modeling requirements.

  2. Speed regulating Effects of Incentive-based Intelligent Speed Adaptation in the short and medium term

    DEFF Research Database (Denmark)

    Agerholm, Niels

    Speed regulating Effects of Incentive-based Intelligent Speed Adaptation in the short and medium term Despite massive improvements in vehicles’ safety equipment, more information and safer road network, inappropriate road safety is still causing that more than 250 people are killed and several...... thousands injured each year in Denmark. Until a few years ago the number of fatalities in most countries had decreased while the amount of traffic increased. However, this trend has been replaced by a more uncertain development towards a constant or even somewhat increasing risk. Inappropriate speeding...... is a central cause for the high number of fatalities on the roads. Despite speed limits, speed limit violating driving behaviour is still widespread in Denmark. Traditional solutions to prevent speed violation have been enforcement, information, and enhanced road design. It seems, however, hard to achieve...

  3. MOE-Analysis for Oversaturated Flow with Interrupted Facility and Heterogeneous Traffic for Urban Roads

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Sharma

    2012-09-01

    Full Text Available Speed-flow functions have been developed by several transportation experts to predict accurately the speed of urban road networks. HCM Speed-Flow Curve, BPR Curve, MTC Speed-Flow Curve, Akçelik Speed-Flow Curve are some extraordinary efforts to define the shape of speed-flow curves. However, the complexity of driver's behaviour, interactions among different type of vehicles, lateral clearance, co-relation of driver's psychology with vehicular characteristics and interdependence of various variables of traffic has led to continuous development and refinement of speed-flow curves. The problem gets more difficult in the case of urban roads with heterogeneous traffic, oversaturated flow and signalized network (which includes some unsignalized intersections as well. This paper presents analysis for various measures of effectiveness (MOE for urban roads with interrupted flow comprising heterogeneous traffic. Model has been developed for heterogeneous traffic under constraints of roadway geometry, vehicle characteristics, driving behaviour and traffic controls. The model developed in this paper predicts speed, delay, average queue and maximum queue estimates for urban roads and quantifies congestion for oversaturated conditions. The investigation details the oversaturated portion of flow in particular.

  4. Florida intercity high speed rail passenger service

    Energy Technology Data Exchange (ETDEWEB)

    Najafi, F.T.; Watford, S.; Moore, G.; Des, A. [Florida Univ., Gainesville, FL (United States). Dept. of Civil Engineering

    1997-10-01

    Plans for a new high-speed rail (HSR) transportation system in Florida were reviewed. HSR is believed to be the least expensive, most energy-efficient and least environmentally harmful alternative to air and highway travel. The system in Florida will be used as a case study to determine its overall impact on the environment, people and economy. The 300-plus mile system will move travelers at speeds of over 200 mph between Miami, Orlando, and Tampa. The study will identify the impacts of a HSR system on existing transportation networks, environment, energy, growth and growth distribution, safety, economy, travel time, and tourism. Transportation problems and the innovative mechanisms needed to realize the joint public and private venture approach to planning, locating, permitting, managing, financing, constructing and maintaining an inter-regional HSR line for the state were studied. The all-electric train would greatly help the environment in two ways: (1) zero emissions from the train itself, and (2) the reduction of trips by automobile and aircraft would reduce the amount of fuel and energy being used. 4 refs., 1 fig.

  5. Cruise speed reduction for air traffic flow management

    OpenAIRE

    Delgado Muñoz, Luis

    2013-01-01

    Avui dia un considerable nombre d’infraestructures del transport aeri tenen problemes de congestió. Aquesta situació es veu empitjorada amb l’increment de trànsit existent i amb la seva densitat deguda al sistema de hub i spoke utilitzat per les companyies aèries. Aquesta congestió es veu agreujada puntualment per disminucions de capacitat per causes com la meteorologia. Per mitigar aquests desequilibris, normalment són implementades mesures de gestió del flux de transit aeri (ATFM), sent el ...

  6. Miles, speed, and technology: Traffic safety under oligopolistic insurance

    NARCIS (Netherlands)

    Dementieva, M.; Verhoef, E.T.

    2016-01-01

    We study road safety when insurance companies have market power, and can influence drivers' behavior via insurance premiums. We obtain first- and second-best premiums for different insurance market structures. The insurance program consists of an insurance premium, and marginal dependencies of that

  7. Experiments simulation and design to set traffic lights operation rules

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez Garcia, J.A.

    2016-07-01

    In this paper it is used the experimental design to minimize the travel time of motor vehicles, in one of the most important avenues of Celaya City in Guanajuato, Mexico, by means of optimal synchronization of existing traffic lights. In the optimization process three factors are considered: the traffic lights’ cycle times, the synchrony defined as stepped, parallel and actual, and speed limit, each one with 3 evaluation levels. The response variables to consider are: motor vehicles’ travel time, fuel consumption and greenhouse effect gas (CO2) emissions. The different experiments are performed using the simulation model developed in the PTV-VISSIM software, which represents the vehicle traffic system. The obtained results for the different proposed scenarios allow to find proper levels at which the vehicle traffic system must be operated in order to improve mobility, to reduce contamination rates and decrease the fuel consumption for the different motor vehicles that use the avenue. (Author)

  8. Modelling the effects of road traffic safety measures.

    Science.gov (United States)

    Lu, Meng

    2006-05-01

    A model is presented for assessing the effects of traffic safety measures, based on a breakdown of the process in underlying components of traffic safety (risk and consequence), and five (speed and conflict related) variables that influence these components, and are influenced by traffic safety measures. The relationships between measures, variables and components are modelled as coefficients. The focus is on probabilities rather than historical statistics, although in practice statistics may be needed to find values for the coefficients. The model may in general contribute to improve insight in the mechanisms between traffic safety measures and their safety effects. More specifically it allows comparative analysis of different types of measures by defining an effectiveness index, based on the coefficients. This index can be used to estimate absolute effects of advanced driver assistance systems (ADAS) related measures from absolute effects of substitutional (in terms of safety effects) infrastructure measures.

  9. Modelling traffic flows with intelligent cars and intelligent roads

    NARCIS (Netherlands)

    van Arem, Bart; Tampere, Chris M.J.; Malone, Kerry

    2003-01-01

    This paper addresses the modeling of traffic flows with intelligent cars and intelligent roads. It will describe the modeling approach MIXIC and review the results for different ADA systems: Adaptive Cruise Control, a special lane for Intelligent Vehicles, cooperative following and external speed

  10. How traffic law enforcement can contribute to safer roads.

    NARCIS (Netherlands)

    Adminaite, D. Jost, G. Stipdonk, H. & Ward, H.

    2016-01-01

    Exceeding speed limits, drink or distracted driving and failure to wear a seat belt are still the leading causes of death and serious injury on European roads. Despite legislation designed to prevent all four, many drivers involved in fatal traffic collisions clearly failed to comply with one or

  11. Advancing Traffic Flow Theory Using Empirical Microscopic Data

    Science.gov (United States)

    2015-01-01

    As reviewed in Section 1.1, much of traffic flow theory depends a fundamental relationship (FR) between flow, density, and space mean speed; either explicitly, e.g., hydrodynamic models such as LWR (Lighthill and Whitham, 1955, and Richards, 1956) or...

  12. Applicability of models to estimate traffic noise for urban roads.

    Science.gov (United States)

    Melo, Ricardo A; Pimentel, Roberto L; Lacerda, Diego M; Silva, Wekisley M

    2015-01-01

    Traffic noise is a highly relevant environmental impact in cities. Models to estimate traffic noise, in turn, can be useful tools to guide mitigation measures. In this paper, the applicability of models to estimate noise levels produced by a continuous flow of vehicles on urban roads is investigated. The aim is to identify which models are more appropriate to estimate traffic noise in urban areas since several models available were conceived to estimate noise from highway traffic. First, measurements of traffic noise, vehicle count and speed were carried out in five arterial urban roads of a brazilian city. Together with geometric measurements of width of lanes and distance from noise meter to lanes, these data were input in several models to estimate traffic noise. The predicted noise levels were then compared to the respective measured counterparts for each road investigated. In addition, a chart showing mean differences in noise between estimations and measurements is presented, to evaluate the overall performance of the models. Measured Leq values varied from 69 to 79 dB(A) for traffic flows varying from 1618 to 5220 vehicles/h. Mean noise level differences between estimations and measurements for all urban roads investigated ranged from -3.5 to 5.5 dB(A). According to the results, deficiencies of some models are discussed while other models are identified as applicable to noise estimations on urban roads in a condition of continuous flow. Key issues to apply such models to urban roads are highlighted.

  13. The economic effects of high speed rail investment

    OpenAIRE

    de Rus, Ginés

    2008-01-01

    The allocation of traffic between different transport modes follows transport user decisions which depend on the generalized cost of travel in the available alternatives. High Speed Rail (HSR) investment is a government decision with significant effects on the generalized cost of rail transport; and therefore on the modal split in corridors where private operators compete for traffic and charge prices close to total producer costs (infrastructure included). The rationale for HSR investment is...

  14. Modeling pedestrian crossing speed profiles considering speed change behavior for the safety assessment of signalized intersections.

    Science.gov (United States)

    Iryo-Asano, Miho; Alhajyaseen, Wael K M

    2017-11-01

    Pedestrian safety is one of the most challenging issues in road networks. Understanding how pedestrians maneuver across an intersection is the key to applying countermeasures against traffic crashes. It is known that the behaviors of pedestrians at signalized crosswalks are significantly different from those in ordinary walking spaces, and they are highly influenced by signal indication, potential conflicts with vehicles, and intersection geometries. One of the most important characteristics of pedestrian behavior at crosswalks is the possible sudden speed change while crossing. Such sudden behavioral change may not be expected by conflicting vehicles, which may lead to hazardous situations. This study aims to quantitatively model the sudden speed changes of pedestrians as they cross signalized crosswalks under uncongested conditions. Pedestrian speed profiles are collected from empirical data and speed change events are extracted assuming that the speed profiles are stepwise functions. The occurrence of speed change events is described by a discrete choice model as a function of the necessary walking speed to complete crossing before the red interval ends, current speed, and the presence of turning vehicles in the conflict area. The amount of speed change before and after the event is modeled using regression analysis. A Monte Carlo simulation is applied for the entire speed profile of the pedestrians. The results show that the model can represent the pedestrian travel time distribution more accurately than the constant speed model. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. The Effects of a Rectangular Rapid-Flashing Beacon on Vehicle Speed

    Science.gov (United States)

    VanWagner, Michelle; Van Houten, Ron; Betts, Brian

    2011-01-01

    In 2008, nearly 31% of vehicle fatalities were related to failure to adhere to safe vehicle speeds (National Highway Traffic Safety Administration [NHTSA], 2009). The current study evaluated the effect of a rectangular rapid-flashing beacon (RRFB) triggered by excessive speed on vehicle speed using a combined alternating treatments and reversal…

  16. Emergent traffic jams

    International Nuclear Information System (INIS)

    Nagel, K.; Paczuski, M.

    1995-01-01

    We study a single-lane traffic model that is based on human driving behavior. The outflow from a traffic jam self-organizes to a critical state of maximum throughput. Small perturbations of the outflow far downstream create emergent traffic jams with a power law distribution P(t)∼t -3/2 of lifetimes t. On varying the vehicle density in a closed system, this critical state separates lamellar and jammed regimes and exhibits 1/f noise in the power spectrum. Using random walk arguments, in conjunction with a cascade equation, we develop a phenomenological theory that predicts the critical exponents for this transition and explains the self-organizing behavior. These predictions are consistent with all of our numerical results

  17. Emergent traffic jams

    Science.gov (United States)

    Nagel, Kai; Paczuski, Maya

    1995-04-01

    We study a single-lane traffic model that is based on human driving behavior. The outflow from a traffic jam self-organizes to a critical state of maximum throughput. Small perturbations of the outflow far downstream create emergent traffic jams with a power law distribution P(t)~t-3/2 of lifetimes t. On varying the vehicle density in a closed system, this critical state separates lamellar and jammed regimes and exhibits 1/f noise in the power spectrum. Using random walk arguments, in conjunction with a cascade equation, we develop a phenomenological theory that predicts the critical exponents for this transition and explains the self-organizing behavior. These predictions are consistent with all of our numerical results.

  18. Differences of Driving Experience and Gender on Traffic Offences Among Malaysian Motorists

    Directory of Open Access Journals (Sweden)

    Liew Sharifah

    2017-01-01

    Full Text Available This study attempt to examine the influence of driving experience and gender on different traffic offences. Questionnaire survey was conducted to measure the frequency of committing eleven types of traffic. Data collected were analysed using t-test and Chi-square. Results indicate that male drivers have high score in speeding, red light running, tailgating and using emergency lane. Significant differences emerged between driving experiences in speeding, red light running, dangerously cutting into traffic, using hand phone while driving/riding and driving/riding with noncompliance specification vehicle.

  19. Traffic Light Detection

    DEFF Research Database (Denmark)

    Philipsen, Mark Philip; Jensen, Morten Bornø; Møgelmose, Andreas

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any intelligent vehicle, which must function in the existing infrastructure. Pedestrian and sign detection have recently seen great improvements due to the introduction of learning based detectors using integral channel features. A similar push...... database is collected based on footage from US roads. The database consists of both test and training data, totaling 46,418 frames and 112,971 annotated traffic lights, captured in continuous sequences under a varying light and weather conditions. The learning based detector achieves an AUC of 0.4 and 0...

  20. Intelligent Traffic Quantification System

    Science.gov (United States)

    Mohanty, Anita; Bhanja, Urmila; Mahapatra, Sudipta

    2017-08-01

    Currently, city traffic monitoring and controlling is a big issue in almost all cities worldwide. Vehicular ad-hoc Network (VANET) technique is an efficient tool to minimize this problem. Usually, different types of on board sensors are installed in vehicles to generate messages characterized by different vehicle parameters. In this work, an intelligent system based on fuzzy clustering technique is developed to reduce the number of individual messages by extracting important features from the messages of a vehicle. Therefore, the proposed fuzzy clustering technique reduces the traffic load of the network. The technique also reduces congestion and quantifies congestion.

  1. Low Speed Automation, a French Initiative

    OpenAIRE

    Sébastien, Glaser; Maurice, Cour; Lydie, Nouveliere; Alain, Lambert; Fawzi, Nashashibi; Jean-Christophe, Popieul; Benjamin, Mourllion

    2012-01-01

    International audience; Nowadays, vehicle safety is constantly increasing thanks to the improvement of vehicle passive and active safety. However, on a daily usage of the car, traffic jams remains a problem. With limited space for road infrastructure, automation of the driving task on specific situation seems to be a possible solution. The French project ABV, which stands for low speed automation, tries to demonstrate the feasibility of the concept and to prove the benefits. In this article, ...

  2. Optical illusions and life-threatening traffic crashes: A perspective on aerial perspective.

    Science.gov (United States)

    Redelmeier, Donald A; Raza, Sheharyar

    2018-05-01

    Aerial perspective illusion is a feature of visual perception where landscapes appear relatively close in clear light and distant in dim light. We hypothesized that bright sunlight might cause drivers to perceive distant terrain as relatively close and misinterpret the approach speed of surrounding landscape as unduly slow. This hypothesis would mean, in turn, that drivers in bright sunlight may underestimate their progress on the road, compensate by traveling at a faster baseline speed, and ultimately increase the prevailing risk of a life-threatening traffic crash. We conducted three pilot studies to illustrate how the illusion might contribute to a life- threatening traffic crash. The first illustration used a questionnaire to demonstrate that most respondents were mistaken when judging the distance between simple balls in different positions. The second illustration involved an experimental manipulation to assess whether aerial perspective influenced judgments about the relative positions of vehicles in traffic. The third illustration analyzed a segment of high-volume fast-speed traffic and found an increased frequency of speeding under bright sunlight. Together with past work based on the visual arts, these examples illustrate how an aerial perspective illusion can affect distance perception, may appear in realistic traffic situations, and could potentially contribute to the risk of a life-threatening traffic crash. An awareness of this hypothesis might lead to applications on how optical illusions could extend to everyday traffic and might potentially inform safety warnings to prevent life- threatening crashes. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. National guidelines for traffic calming

    CSIR Research Space (South Africa)

    Schermers, G

    1998-03-01

    Full Text Available and provides a policy framework on traffic calming. It also describes the administrative and management procedures required to meet policy objectives in the implementation and monitoring of traffic calming in urban areas. Related legal requirements, liability...

  4. Texas traffic thermostat marketing package.

    Science.gov (United States)

    2013-04-01

    The traffic thermostat decision tool is built to help guide the user through a logical, step-wise, process of examining potential changes to their Manage Lane/toll facility. : **NOTE: Project Title: Application of the Traffic Thermostat Framework. Ap...

  5. 2016 Traffic Safety Culture Index

    Science.gov (United States)

    ... Newsroom SEARCH Driver Behavior & Performance 2016 Traffic Safety Culture Index This report presents the results of our annual Traffic Safety Culture Index survey, providing data on the attitudes and ...

  6. Texas traffic thermostat software tool.

    Science.gov (United States)

    2013-04-01

    The traffic thermostat decision tool is built to help guide the user through a logical, step-wise, process of examining potential changes to their Manage Lane/toll facility. : **NOTE: Project Title: Application of the Traffic Thermostat Framework. Ap...

  7. A PHOTOGRAMMETRIC APPRAOCH FOR AUTOMATIC TRAFFIC ASSESSMENT USING CONVENTIONAL CCTV CAMERA

    Directory of Open Access Journals (Sweden)

    N. Zarrinpanjeh

    2015-12-01

    Full Text Available One of the most practical tools for urban traffic monitoring is CCTV imaging which is widely used for traffic map generation and updating through human surveillance. But due to the expansion of urban road network and the use of huge number of CCTV cameras, visual inspection and updating of traffic sometimes seems to be ineffective and time consuming and therefore not providing real-time robust update. In this paper a method for vehicle detection accounting and speed estimation is proposed to give a more automated solution for traffic assessment. Through removing violating objects and detection of vehicles via morphological filtering and also classification of moving objects at the scene vehicles are counted and traffic speed is estimated. The proposed method is developed and tested using two datasets and evaluation values are computed. The results show that the successfulness of the algorithm decreases by about 12 % due to decrease in illumination quality of imagery.

  8. Blind haste: As light decreases, speeding increases.

    Directory of Open Access Journals (Sweden)

    Emanuel de Bellis

    Full Text Available Worldwide, more than one million people die on the roads each year. A third of these fatal accidents are attributed to speeding, with properties of the individual driver and the environment regarded as key contributing factors. We examine real-world speeding behavior and its interaction with illuminance, an environmental property defined as the luminous flux incident on a surface. Drawing on an analysis of 1.2 million vehicle movements, we show that reduced illuminance levels are associated with increased speeding. This relationship persists when we control for factors known to influence speeding (e.g., fluctuations in traffic volume and consider proxies of illuminance (e.g., sight distance. Our findings add to a long-standing debate about how the quality of visual conditions affects drivers' speed perception and driving speed. Policy makers can intervene by educating drivers about the inverse illuminance‒speeding relationship and by testing how improved vehicle headlights and smart road lighting can attenuate speeding.

  9. Framework for Traffic Congestion Prediction

    NARCIS (Netherlands)

    Zaki, J.F.W.; Ali-Eldin, A.M.T.; Hussein, S.E.; Saraya, S.F.; Areed, F.F.

    2016-01-01

    Traffic Congestion is a complex dilemma facing most major cities. It has undergone a lot of research since the early 80s in an attempt to predict traffic in the short-term. Recently, Intelligent Transportation Systems (ITS) became an integral part of traffic research which helped in modeling and

  10. Dynamic control of traffic lights

    NARCIS (Netherlands)

    Haijema, Rene; Hendrix, Eligius M.T.; Wal, van der Jan

    2017-01-01

    Traffic lights are put in place to dynamically change priority between traffic participants. Commonly, the duration of green intervals and the grouping, and ordering in which traffic flows are served are pre-fixed. In this chapter, the problem of minimizing vehicle delay at isolated intersections is

  11. Traffic sign detection and analysis

    DEFF Research Database (Denmark)

    Møgelmose, Andreas; Trivedi, Mohan M.; Moeslund, Thomas B.

    2012-01-01

    Traffic sign recognition (TSR) is a research field that has seen much activity in the recent decade. This paper introduces the problem and presents 4 recent papers on traffic sign detection and 4 recent papers on traffic sign classification. It attempts to extract recent trends in the field...

  12. ITSA: Internet Traffic Statistics Archive

    NARCIS (Netherlands)

    Hoogesteger, Martijn; de Oliveira Schmidt, R.; Pras, Aiko

    Motivated by the fact that comprehensive and long term Internet traffic measurements can be hard to obtain, we have proposed and developed the Internet Traffic Statistics Archive (ITSA). Since 2013, ITSA concentrates reports on high-level statistics of Internet traffic worldwide. Examples of

  13. Distraction in traffic.

    NARCIS (Netherlands)

    2013-01-01

    Many drivers, as well as cyclists and pedestrians, are occupied with all kinds of activities that can distract their attention from traffic, like listening to music, conducting a conversation on their mobile phone, or reading and typing text messages (texting). Distraction has negative effects on

  14. TRAFFIC - Wildlife Trade

    Science.gov (United States)

    growing in Eastern and Southern Africa in response to increased human populations and poverty. fuel-trees etc. Conversely, extreme poverty of others means they regard wildlife as a means to meet their short worldwide. You can also find us online in: mainland China, India, Japan, Taiwan TRAFFIC is a strategic

  15. Decline traffic information system

    Energy Technology Data Exchange (ETDEWEB)

    Du Plessis, K [Computer Sciences Corporation (CSC), Sydney (Australia)

    2007-09-06

    BHP Billion (BHPB) Cannington has experienced problems in regards to their traffic flow in the decline at the mine. The problems related to reports on near misses of vehicles moving towards each other in the decline. The decline is also to narrow for trucks to pass each other and the operators need to be aware of oncoming traffic in the decline to ensure they could take early evasive steps to ensure the rules of right of way in the decline are adhered to. BHPB Cannington requested CSC to conduct a problem analysis and to provide a solutions proposal to Cannington. The solution was put forward as an augmentation of their current safety procedures used with in the decline. During this phase of the project CSC developed a solutions architecture which involved the use of Active (Radio Frequency Identification) RFID tagging which will enable vehicle movement tracking on a real time basis after which the appropriate traffic movement can be relayed to the operators in the decline. The primary objective of the DTIS is to provide accurate information of traffic movement in the decline and present that information to the operators of the decline IN THE DECLINE upon which they would make their decisions. (orig.)

  16. Visualization of vessel traffic

    NARCIS (Netherlands)

    Willems, C.M.E.

    2011-01-01

    Moving objects are captured in multivariate trajectories, often large data with multiple attributes. We focus on vessel traffic as a source of such data. Patterns appearing from visually analyzing attributes are used to explain why certain movements have occurred. In this research, we have developed

  17. Alcohol and Traffic Safety.

    Science.gov (United States)

    Dickman, Frances Baker, Ed.

    1988-01-01

    Seven papers discuss current issues and applied social research concerning alcohol traffic safety. Prevention, policy input, methodology, planning strategies, anti-drinking/driving programs, social-programmatic orientations of Mothers Against Drunk Driving, Kansas Driving Under the Influence Law, New Jersey Driving While Impaired Programs,…

  18. Impact of traffic noise on railway traffic safety

    Directory of Open Access Journals (Sweden)

    Zdravko TOŠ

    2008-01-01

    Full Text Available Traffic noise is one of the dominant factors of ergo-assessment. The harmful impact of traffic noise on the engine driver as target group can be studied in isolation from other ergo-assessment factors only in the initial phase of research. The simultaneous action of several related factors in the system of ergo-assessment factors has cumulative effect on the perception and psychomotoric status of the railway traffic participants in the appropriate traffic situation. The initial partial research of traffic noise by a combination of several scientific methods needs to be eventually upgraded by studying the relations among several concurrent important or dominant ergo-assessment factors.

  19. Non-vehicular homicides masquerading as road traffic accidents.

    Science.gov (United States)

    Zine, K U; Mugadlimath, Anand B; Sane, Mandar Ramchandra; Bhuyyar, Chandrashekhar; Rathod, S N

    2016-03-01

    Interfering with or planting evidence to disguise the cause of a death is not uncommon in forensic practice. Homicides staged as road accidents are, however, rarely encountered by crime scene investigators. We report two homicides which were presented as road traffic accidents. Case 1: Dead body of a 35-year-old male was brought for autopsy with history of road traffic accident. Primary police inquiry suggested that the victim was knocked down by a speeding four-wheeler, while walking by the side of a high way with his friends. On postmortem examination the deceased's death was found due to homicidal smothering staged as a road traffic accident. Case 2: Dead body of 40-year-old male was brought for autopsy with history of road traffic accident. It was an unwitnessed crush by a speeding four-wheeler. However, on postmortem examination, the deceased was found to have died from homicidal multiple stab wounds with his death staged as a road traffic accident. Importance of meticulous autopsy to determine accurately the cause of death is emphasized. © The Author(s) 2015.

  20. ENHANCEMENT OF ROAD SAFETY THROUGH MORE EFFECTIVE ROAD AND TRAFFIC MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Tomasz SZCZURASZEK

    2016-07-01

    Full Text Available To make the policy aimed at mitigating the risk of road incidents more effective, Poland should see the introduction of the more efficient road and traffic management. In November 2008 the European Parliament and the European Council published the Directive on "infrastructure safety management" which provides guidance on the procedures for carrying impact assessments of traffic safety, traffic safety audits, safety management on the road network and monitoring traffic safety in Member States. In this article, the authors have proposed a systemic approach to road and traffic management, involving the implementation of consistent procedures that should include regular revisions of roads, eliminating hazardous sites, speed management, as well as the approval and implementation of traffic organization designs.

  1. Evaluation of sounds for hybrid and electric vehicles operating at low speed

    Science.gov (United States)

    2012-10-22

    Electric vehicles (EV) and hybrid electric vehicles (HEVs), operated at low speeds may reduce auditory cues used by pedestrians to assess the state of nearby traffic creating a safety issue. This field study compares the auditory detectability of num...

  2. Empirical analysis of an in-car speed, headway and lane use Advisory system

    NARCIS (Netherlands)

    Schakel, W.J.; Van Arem, B.; Van Lint, J.W.C.

    2014-01-01

    For a recently developed in-car speed, headway and lane use advisory system, this paper investigates empirically advice validity (advice given in correct traffic circumstances), credibility (advice logical to drivers) and frequency. The system has been developed to optimize traffic flow by giving

  3. Visual Analysis of Speeding Bumps Using Floating Car Dataset

    DEFF Research Database (Denmark)

    Kveladze, Irma; Agerholm, Niels

    2018-01-01

    measures, and also their influence on the driving behaviour of vehicles from a temporal perspective. To fill this gap and understand these aspects, in this research we propose visual analytics techniques. To explore the influence of the bumps on speed change behavior of vehicles, several use case studies...... in three different cities were selected with close cooperation of a traffic domain expert. The aim was first to study influence of the bumps on vehicle volume and speeding from a time perspective. And then, establish any connection between speed bump intervals and vehicle speeding in the selected use cases...

  4. Automated mixed traffic transit vehicle microprocessor controller

    Science.gov (United States)

    Marks, R. A.; Cassell, P.; Johnston, A. R.

    1981-01-01

    An improved Automated Mixed Traffic Vehicle (AMTV) speed control system employing a microprocessor and transistor chopper motor current controller is described and its performance is presented in terms of velocity versus time curves. The on board computer hardware and software systems are described as is the software development system. All of the programming used in this controller was implemented using FORTRAN. This microprocessor controller made possible a number of safety features and improved the comfort associated with starting and shopping. In addition, most of the vehicle's performance characteristics can be altered by simple program parameter changes. A failure analysis of the microprocessor controller was generated and the results are included. Flow diagrams for the speed control algorithms and complete FORTRAN code listings are also included.

  5. Apparatus, system, and method for traffic monitoring

    KAUST Repository

    Claudel, Christian G.

    2016-08-25

    An apparatus, system, and method for traffic monitory can have a Lagrangian inertial measurement unit. The Lagrangian inertial measurement unit can have a processor, an accelerometer, a gyroscope, and/or a wireless transmitter. The processor can have an integrated direction cosine matrix. The accelerometer can be configured to measure linear accelerations of a vehicle and/or can communicate measured linear acceleration to the processor. The gyroscope can be configured to measure rotational accelerations of the vehicle and/or can communicate measured rotational acceleration to the processor. The processor can be configured to calculate estimated vehicle speed and/or estimated vehicle attitude. The wireless transmitter can be configured to wirelessly transmit estimated vehicle speed and/or estimated vehicle attitude. The apparatus, system, and method can be integrated with a wireless sensor network.

  6. Urban Road Traffic Simulation Techniques

    Directory of Open Access Journals (Sweden)

    Ana Maria Nicoleta Mocofan

    2011-09-01

    Full Text Available For achieving a reliable traffic control system it is necessary to first establish a network parameter evaluation system and also a simulation system for the traffic lights plan. In 40 years of history, the computer aided traffic simulation has developed from a small research group to a large scale technology for traffic systems planning and development. In the following thesis, a presentation of the main modeling and simulation road traffic applications will be provided, along with their utility, as well as the practical application of one of the models in a case study.

  7. Web traffic and firm performance

    DEFF Research Database (Denmark)

    Farooq, Omar; Aguenaou, Samir

    2013-01-01

    Does the traffic generated by websites of firms signal anything to stock market participants? Does higher web-traffic translate into availability of more information and therefore lower agency problems? And if answers to above questions are in affirmative, does higher web-traffic traffic translate...... into better firm performance? This paper aims to answer these questions by documenting a positive relationship between the extent of web-traffic and firm performance in the MENA region during the 2010. We argue that higher web-traffic lowers the agency problems in firms by disseminating more information...... to stock market participants. Consequently, lower agency problems translate into better performance. Furthermore, we also show that agency reducing role of web-traffic is more pronounced in regimes where information environment is already bad. For example, our results show stronger impact of web...

  8. A theory of traffic congestion at heavy bottlenecks

    Energy Technology Data Exchange (ETDEWEB)

    Kerner, Boris S [Daimler AG, GR/ETI, HPC: G021, 71059 Sindelfingen (Germany)

    2008-05-30

    Spatiotemporal features and physics of vehicular traffic congestion occurring due to heavy highway bottlenecks caused for example by bad weather conditions or accidents are found based on simulations in the framework of three-phase traffic theory. A model of a heavy bottleneck is presented. Under a continuous non-limited increase in bottleneck strength, i.e., when the average flow rate within a congested pattern allowed by the heavy bottleneck decreases continuously up to zero, the evolution of the traffic phases in congested traffic, synchronized flow and wide moving jams, is studied. It is found that at a small enough flow rate within the congested pattern, the pattern exhibits a non-regular structure: a pinch region of synchronized flow within the pattern disappears and appears randomly over time; wide moving jams upstream of the pinch region exhibit a complex non-regular dynamics in which the jams appear and disappear randomly. At greater bottleneck strengths, wide moving jams merge onto a mega-wide moving jam (mega-jam) within which low-speed patterns with a complex non-regular spatiotemporal dynamics occur. We show that when the bottleneck strength is great enough, only the mega-jam survives and synchronized flow remains only within its downstream front separating free flow and congested traffic. Theoretical results presented can explain why no sequence of wide moving jams can often be distinguished in non-homogeneous traffic congestion measured at very heavy bottlenecks caused by bad weather conditions or accidents.

  9. A theory of traffic congestion at heavy bottlenecks

    International Nuclear Information System (INIS)

    Kerner, Boris S

    2008-01-01

    Spatiotemporal features and physics of vehicular traffic congestion occurring due to heavy highway bottlenecks caused for example by bad weather conditions or accidents are found based on simulations in the framework of three-phase traffic theory. A model of a heavy bottleneck is presented. Under a continuous non-limited increase in bottleneck strength, i.e., when the average flow rate within a congested pattern allowed by the heavy bottleneck decreases continuously up to zero, the evolution of the traffic phases in congested traffic, synchronized flow and wide moving jams, is studied. It is found that at a small enough flow rate within the congested pattern, the pattern exhibits a non-regular structure: a pinch region of synchronized flow within the pattern disappears and appears randomly over time; wide moving jams upstream of the pinch region exhibit a complex non-regular dynamics in which the jams appear and disappear randomly. At greater bottleneck strengths, wide moving jams merge onto a mega-wide moving jam (mega-jam) within which low-speed patterns with a complex non-regular spatiotemporal dynamics occur. We show that when the bottleneck strength is great enough, only the mega-jam survives and synchronized flow remains only within its downstream front separating free flow and congested traffic. Theoretical results presented can explain why no sequence of wide moving jams can often be distinguished in non-homogeneous traffic congestion measured at very heavy bottlenecks caused by bad weather conditions or accidents

  10. The impact of a fully idealised high speed train into a constrained fuel transport flask

    International Nuclear Information System (INIS)

    Dowler, H.J.

    1985-05-01

    The outcome of an accident involving a high speed train, travelling at 125 mph and impacting a stationary irradiated fuel transport flask is investigated. The case considered is that of a fully constrained flask and the power cars and carriages are fully idealised. A representation of the impact and an estimate of the resulting force-time curve experienced by the fuel flask are given. It is found that the peak force is not increased by the addition of coaches, but the time duration of the impact is lengthened. (author)

  11. Understanding characteristics in multivariate traffic flow time series from complex network structure

    Science.gov (United States)

    Yan, Ying; Zhang, Shen; Tang, Jinjun; Wang, Xiaofei

    2017-07-01

    Discovering dynamic characteristics in traffic flow is the significant step to design effective traffic managing and controlling strategy for relieving traffic congestion in urban cities. A new method based on complex network theory is proposed to study multivariate traffic flow time series. The data were collected from loop detectors on freeway during a year. In order to construct complex network from original traffic flow, a weighted Froenius norm is adopt to estimate similarity between multivariate time series, and Principal Component Analysis is implemented to determine the weights. We discuss how to select optimal critical threshold for networks at different hour in term of cumulative probability distribution of degree. Furthermore, two statistical properties of networks: normalized network structure entropy and cumulative probability of degree, are utilized to explore hourly variation in traffic flow. The results demonstrate these two statistical quantities express similar pattern to traffic flow parameters with morning and evening peak hours. Accordingly, we detect three traffic states: trough, peak and transitional hours, according to the correlation between two aforementioned properties. The classifying results of states can actually represent hourly fluctuation in traffic flow by analyzing annual average hourly values of traffic volume, occupancy and speed in corresponding hours.

  12. Predicting Light-Duty Vehicle Fuel Economy as a Function of Highway Speed

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hwang, Ho-Ling [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); West, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Huff, Shean [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2013-04-08

    The www.fueleconomy.gov website offers information such as window label fuel economy for city, highway, and combined driving for all U.S.-legal light-duty vehicles from 1984 to the present. The site is jointly maintained by the U.S. Department of Energy and the U.S. Environmental Protection Agency (EPA), and also offers a considerable amount of consumer information and advice pertaining to vehicle fuel economy and energy related issues. Included with advice pertaining to driving styles and habits is information concerning the trend that as highway cruising speed is increased, fuel economy will degrade. An effort was undertaken to quantify this conventional wisdom through analysis of dynamometer testing results for 74 vehicles at steady state speeds from 50 to 80 mph. Using this experimental data, several simple models were developed to predict individual vehicle fuel economy and its rate of change over the 50-80 mph speed range interval. The models presented require a minimal number of vehicle attributes. The simplest model requires only the EPA window label highway mpg value (based on the EPA specified estimation method for 2008 and beyond). The most complex of these simple model uses vehicle coast-down test coefficients (from testing prescribed by SAE Standard J2263) known as the vehicle Target Coefficients, and the raw fuel economy result from the federal highway test. Statistical comparisons of these models and discussions of their expected usefulness and limitations are offered.

  13. Inaccuracy in traffic forecasts

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Holm, Mette K. Skamris; Buhl, Søren Ladegaard

    2006-01-01

    This paper presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth US$58 billion. The study shows with very high statistical significance...... that forecasters generally do a poor job of estimating the demand for transportation infrastructure projects. The result is substantial downside financial and economic risk. Forecasts have not become more accurate over the 30-year period studied. If techniques and skills for arriving at accurate demand forecasts...... forecasting. Highly inaccurate traffic forecasts combined with large standard deviations translate into large financial and economic risks. But such risks are typically ignored or downplayed by planners and decision-makers, to the detriment of social and economic welfare. The paper presents the data...

  14. Safety concepts for the design of transport and traffic facilities for pedestrians, cyclists, children and disabled in urban areas. Contribution to the 5th National Congress on Traffic Safety, Barcelona, Spain, November 24-26, 1982.

    NARCIS (Netherlands)

    Asmussen, E.

    1982-01-01

    The "vulnerable" road users, pedestrians, cyclists, children and disabled in urban -areas mainly are victims of motorised traffic. The intensity and speed of this motorized traffic are the main agents for the unsafety of the "vulnerable" road users. Safety concepts for urban areas should be directed

  15. A Cooperative Traffic Control of Vehicle–Intersection (CTCVI) for the Reduction of Traffic Delays and Fuel Consumption

    Science.gov (United States)

    Li, Jinjian; Dridi, Mahjoub; El-Moudni, Abdellah

    2016-01-01

    The problem of reducing traffic delays and decreasing fuel consumption simultaneously in a network of intersections without traffic lights is solved by a cooperative traffic control algorithm, where the cooperation is executed based on the connection of Vehicle-to-Infrastructure (V2I). This resolution of the problem contains two main steps. The first step concerns the itinerary of which intersections are chosen by vehicles to arrive at their destination from their starting point. Based on the principle of minimal travel distance, each vehicle chooses its itinerary dynamically based on the traffic loads in the adjacent intersections. The second step is related to the following proposed cooperative procedures to allow vehicles to pass through each intersection rapidly and economically: on one hand, according to the real-time information sent by vehicles via V2I in the edge of the communication zone, each intersection applies Dynamic Programming (DP) to cooperatively optimize the vehicle passing sequence with minimal traffic delays so that the vehicles may rapidly pass the intersection under the relevant safety constraints; on the other hand, after receiving this sequence, each vehicle finds the optimal speed profiles with the minimal fuel consumption by an exhaustive search. The simulation results reveal that the proposed algorithm can significantly reduce both travel delays and fuel consumption compared with other papers under different traffic volumes. PMID:27999333

  16. A Cooperative Traffic Control of Vehicle–Intersection (CTCVI for the Reduction of Traffic Delays and Fuel Consumption

    Directory of Open Access Journals (Sweden)

    Jinjian Li

    2016-12-01

    Full Text Available The problem of reducing traffic delays and decreasing fuel consumption simultaneously in a network of intersections without traffic lights is solved by a cooperative traffic control algorithm, where the cooperation is executed based on the connection of Vehicle-to-Infrastructure (V2I. This resolution of the problem contains two main steps. The first step concerns the itinerary of which intersections are chosen by vehicles to arrive at their destination from their starting point. Based on the principle of minimal travel distance, each vehicle chooses its itinerary dynamically based on the traffic loads in the adjacent intersections. The second step is related to the following proposed cooperative procedures to allow vehicles to pass through each intersection rapidly and economically: on one hand, according to the real-time information sent by vehicles via V2I in the edge of the communication zone, each intersection applies Dynamic Programming (DP to cooperatively optimize the vehicle passing sequence with minimal traffic delays so that the vehicles may rapidly pass the intersection under the relevant safety constraints; on the other hand, after receiving this sequence, each vehicle finds the optimal speed profiles with the minimal fuel consumption by an exhaustive search. The simulation results reveal that the proposed algorithm can significantly reduce both travel delays and fuel consumption compared with other papers under different traffic volumes.

  17. Motorcycle and scooter speeds approaching urban intersections.

    Science.gov (United States)

    Walton, D; Buchanan, J

    2012-09-01

    Five urban, uncontrolled T-intersections known to be motorcycle crash 'black spots' were monitored using instrumentation and a roadside observer. Two sets of twelve-hour observations were collected for each site (N≈100,000). Instrumentation recorded the 'events' of vehicles passing to measure, speed, direction, lane position, vehicle type (broadly characterised) and headway. Observers further recorded times of bicycle events, type of motorcycle (scooters or motorcycles), the behaviour of motorcycles and the use of 'high conspicuity' gear such as clothing or helmets. Results establish that motorcycles travel around 10% faster than the other traffic (car mean speed=34.97 km/h), with motorcycles travelling on average 3.3 km/h faster than cars. Motorcycles were 3.4 times more likely to be exceeding the speed limit than cars. Similar results are described for scooters. Also examined are the influences on mean speeds such as the time of day, the presence of a car at the t-intersection, and the influence of free headway. The results are compared for robustness across locations and days. It is concluded that in urban areas motorcycles are travelling significantly faster than other traffic. These findings are discussed against a concern to reduce motorcycle crashes by improving conspicuity and previous research that implicates a 'looked-but-failed-to-see' effect for car drivers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Assessing Road Traffic Expression

    Directory of Open Access Journals (Sweden)

    Fábio Silva

    2014-12-01

    Full Text Available Road traffic is a problem which is increasing in cities with large population. Unrelated to this fact the number of portable and wearable devices has also been increasing throughout the population of most countries. With this advent, the capacity to monitor and register data about people habits and locations as well as more complex data such as intensity and strength of movements has created an opportunity to contribute to the general wealth and comfort within these environments. Ambient Intelligence and Intelligent Decision Making processes can benefit from the knowledge gathered by these devices to improve decisions on everyday tasks such as deciding navigation routes by car, bicycle or other means of transportation and avoiding route perils. The concept of computational sustainability may also be applied to this problem. Current applications in this area demonstrate the usefulness of real time system that inform the user of certain conditions in the surrounding area. On the other hand, the approach presented in this work aims to describe models and approaches to automatically identify current states of traffic inside cities and use methods from computer science to improve overall comfort and the sustainability of road traffic both with the user and the environment in mind. Such objective is delivered by analyzing real time contributions from those mobile ubiquitous devices to identifying problematic situations and areas under a defined criteria that have significant influence towards a sustainable use of the road transport infrastructure.

  19. Networks and their traffic in multiplayer games

    Directory of Open Access Journals (Sweden)

    Cristian Andrés Melo López

    2016-06-01

    Full Text Available Computer games called multiplayer real-time, or (MCG are at the forefront of the use of the possibilities of the network. Research on this subject have been made for military simulations, virtual reality systems, computer support teamwork, the solutions diverge on the problems posed by MCG. With this in mind, this document provides an overview of the four issues affecting networking at the MCG. First, network resources (bandwidth, latency and computing capacity, together with the technical limits within which the MCG must operate. Second, the distribution concepts include communication architectures (peer-to-peer, client / server, server / network, and data and control architectures (centralized, distributed and reproduced .Thirdly, scalability allows the MCG to adapt to changes in parameterization resources. Finally, security is intended to fend off the traps and vandalism, which are common in online games; to check traffic, particularly these games we decided to take the massively multiplayer game League of Legends, a scene corresponding to a situation of real life in a network of ADSL access network is deployed has been simulated by using NS2 Three variants of TCP, it means SACK TCP, New Reno TCP, and TCP Vegas, have been considered for the cross traffic. The results show that TCP Vegas is able to maintain a constant speed while racing against the game traffic, since it avoids the packet loss and the delays in the tail caused by high peaks, without increasing the size of the sender window. SACK TCP and TCP New Reno, on the other hand, tend to increase continuously the sender window size, which could allow a greater loss of packages and also to cause unwanted delays for the game traffic.

  20. Traffic control on a railway crossing with elements of utility theory

    Directory of Open Access Journals (Sweden)

    Abramova L.S.

    2016-08-01

    Full Text Available An approach to the management of vehicles at a railway crossing in order to improve the road safety is considered. To do this, it is suggested to introduce the dynamic motion control modes on the road, which consist in reducing the speed at a certain distance from the railway crossing and depends on its condition. The value of the recommended speed is displayed on the managed road signs and is calculated in real-time traffic controller at the railway crossing control point. The mark location is determined based on traffic intensity equalization that affects both the traffic intensity of the railway crossing and the road section on the approach to it. To analyze such events directed to improve the traffic on level crossings it is suggested to use the elements of utility theory to further develop the traffic control algorithm. For this purpose there was built a decision tree for the existing conditions at the railway crossing and at the introduction of the dynamic management, which indicates the result of decision taken by the change in the selected criteria of efficiency of traffic management at the railway crossing. Such an approach can reduce the number of road accidents and to increase the capacity of vehicular traffic at a particular road section to the technical means of attracting the driver's attention to the complex road by forced reduction in speed not only before the railway crossing, but also in at the approach to it.

  1. Evaluation of Intersection Traffic Control Measures through Simulation

    Science.gov (United States)

    Asaithambi, Gowri; Sivanandan, R.

    2015-12-01

    Modeling traffic flow is stochastic in nature due to randomness in variables such as vehicle arrivals and speeds. Due to this and due to complex vehicular interactions and their manoeuvres, it is extremely difficult to model the traffic flow through analytical methods. To study this type of complex traffic system and vehicle interactions, simulation is considered as an effective tool. Application of homogeneous traffic models to heterogeneous traffic may not be able to capture the complex manoeuvres and interactions in such flows. Hence, a microscopic simulation model for heterogeneous traffic is developed using object oriented concepts. This simulation model acts as a tool for evaluating various control measures at signalized intersections. The present study focuses on the evaluation of Right Turn Lane (RTL) and Channelised Left Turn Lane (CLTL). A sensitivity analysis was performed to evaluate RTL and CLTL by varying the approach volumes, turn proportions and turn lane lengths. RTL is found to be advantageous only up to certain approach volumes and right-turn proportions, beyond which it is counter-productive. CLTL is found to be advantageous for lower approach volumes for all turn proportions, signifying the benefits of CLTL. It is counter-productive for higher approach volume and lower turn proportions. This study pinpoints the break-even points for various scenarios. The developed simulation model can be used as an appropriate intersection lane control tool for enhancing the efficiency of flow at intersections. This model can also be employed for scenario analysis and can be valuable to field traffic engineers in implementing vehicle-type based and lane-based traffic control measures.

  2. Sonification of network traffic flow for monitoring and situational awareness

    Science.gov (United States)

    2018-01-01

    Maintaining situational awareness of what is happening within a computer network is challenging, not only because the behaviour happens within machines, but also because data traffic speeds and volumes are beyond human ability to process. Visualisation techniques are widely used to present information about network traffic dynamics. Although they provide operators with an overall view and specific information about particular traffic or attacks on the network, they often still fail to represent the events in an understandable way. Also, because they require visual attention they are not well suited to continuous monitoring scenarios in which network administrators must carry out other tasks. Here we present SoNSTAR (Sonification of Networks for SiTuational AwaReness), a real-time sonification system for monitoring computer networks to support network administrators’ situational awareness. SoNSTAR provides an auditory representation of all the TCP/IP traffic within a network based on the different traffic flows between between network hosts. A user study showed that SoNSTAR raises situational awareness levels by enabling operators to understand network behaviour and with the benefit of lower workload demands (as measured by the NASA TLX method) than visual techniques. SoNSTAR identifies network traffic features by inspecting the status flags of TCP/IP packet headers. Combinations of these features define particular traffic events which are mapped to recorded sounds to generate a soundscape that represents the real-time status of the network traffic environment. The sequence, timing, and loudness of the different sounds allow the network to be monitored and anomalous behaviour to be detected without the need to continuously watch a monitor screen. PMID:29672543

  3. Sonification of network traffic flow for monitoring and situational awareness.

    Science.gov (United States)

    Debashi, Mohamed; Vickers, Paul

    2018-01-01

    Maintaining situational awareness of what is happening within a computer network is challenging, not only because the behaviour happens within machines, but also because data traffic speeds and volumes are beyond human ability to process. Visualisation techniques are widely used to present information about network traffic dynamics. Although they provide operators with an overall view and specific information about particular traffic or attacks on the network, they often still fail to represent the events in an understandable way. Also, because they require visual attention they are not well suited to continuous monitoring scenarios in which network administrators must carry out other tasks. Here we present SoNSTAR (Sonification of Networks for SiTuational AwaReness), a real-time sonification system for monitoring computer networks to support network administrators' situational awareness. SoNSTAR provides an auditory representation of all the TCP/IP traffic within a network based on the different traffic flows between between network hosts. A user study showed that SoNSTAR raises situational awareness levels by enabling operators to understand network behaviour and with the benefit of lower workload demands (as measured by the NASA TLX method) than visual techniques. SoNSTAR identifies network traffic features by inspecting the status flags of TCP/IP packet headers. Combinations of these features define particular traffic events which are mapped to recorded sounds to generate a soundscape that represents the real-time status of the network traffic environment. The sequence, timing, and loudness of the different sounds allow the network to be monitored and anomalous behaviour to be detected without the need to continuously watch a monitor screen.

  4. Investigation of the Link Between Macroscopic Traffic Flow Characteristics and Individual Vehicle Fuel Consumption : Tech Transfer Summary

    Science.gov (United States)

    2017-10-01

    The objective of this project was to investigate the impacts of several factors, including vehicle characteristics, ambient temperature, season, speed, driving behavior, and traffic flow, on individual vehicle energy consumption.

  5. Senales de Trafico. Ingles-Espanol = Traffic Signs. English-Spanish [and] English-Spanish Road Signs for American Tourists.

    Science.gov (United States)

    Grosse, Philip

    Two English/Spanish bilingual glossaries define words and phrases found on traffic signs. The first is an extensive alphabetical checklist of sign messages, listed in English with translations in Spanish. Some basic traffic and speed limit rules are included. The second volume, in Spanish-to-English form, is a pocket version designed for American…

  6. Traffic density determination and its applications using smartphone

    Directory of Open Access Journals (Sweden)

    Al-Sayed Ahmed Al-Sobky

    2016-03-01

    Full Text Available Smartphone is progressively becoming a dominant platform for many transportation applications. This paper introduces a new application for using smartphones to measure traffic density and speed. The proposed system consists of two smartphones and two cars, with observer to count vehicles between the two cars. This count is utilized with tracking data to give “measured” density and “measured” speed. The travel speed and manual traffic counts were used to derive “calculated” density. Measured density was validated against calculated one, and statistical t-test confirmed that the mean difference between two densities is not significant at 5% level. Calculated flow rates were also comparable to actual counts, with an average error of 8.2%. The proposed system was then applied to measure density on 6 of October Elevated Road in Egypt, and the level of service was determined accordingly on 15 road sections studied on this road. Furthermore, actual speed-density data were fitted using exponential model with R2 of 0.85. Advantages of proposed system qualify it for potential applications in developing countries where available resources limit installation of more costly systems. The application of proposed system is limited to daytime, uninterrupted flow conditions, and traffic streams with less percentage of heavy vehicles.

  7. Two laboratory methods for the calibration of GPS speed meters

    International Nuclear Information System (INIS)

    Bai, Yin; Sun, Qiao; Du, Lei; Yu, Mei; Bai, Jie

    2015-01-01

    The set-ups of two calibration systems are presented to investigate calibration methods of GPS speed meters. The GPS speed meter calibrated is a special type of high accuracy speed meter for vehicles which uses Doppler demodulation of GPS signals to calculate the measured speed of a moving target. Three experiments are performed: including simulated calibration, field-test signal replay calibration, and in-field test comparison with an optical speed meter. The experiments are conducted at specific speeds in the range of 40–180 km h −1 with the same GPS speed meter as the device under calibration. The evaluation of measurement results validates both methods for calibrating GPS speed meters. The relative deviations between the measurement results of the GPS-based high accuracy speed meter and those of the optical speed meter are analyzed, and the equivalent uncertainty of the comparison is evaluated. The comparison results justify the utilization of GPS speed meters as reference equipment if no fewer than seven satellites are available. This study contributes to the widespread use of GPS-based high accuracy speed meters as legal reference equipment in traffic speed metrology. (paper)

  8. Apparatus for measuring speed through the Doppler frequency shift of sound

    Science.gov (United States)

    Schier, Walter

    2011-04-01

    The Doppler frequency shift of sound apparatus is based on a one meter diameter rotary table with a "button" speaker at its outer edge. A semicircular waveguide encloses half the periphery and has a microphone pickup on its wall at the midpoint. The tangential speed of the button speaker can be determined two ways for comparison. One method calculates speed from the frequency shift of sound, the other uses the repeat sound pattern. Agreement to one percent is possible at speeds of about 25 mph. In the lab the microphone output is fed successively to pairs of students at ten computer stations. Students must also perform an exercise in their lab report that introduces them to the red shifted wavelengths of receding galaxies at determined distances from the earth thus introducing them to Hubble's law, the concept of the "Big Bang", and their estimate of the age of the universe.

  9. Traffic Games: Modeling Freeway Traffic with Game Theory.

    Science.gov (United States)

    Cortés-Berrueco, Luis E; Gershenson, Carlos; Stephens, Christopher R

    2016-01-01

    We apply game theory to a vehicular traffic model to study the effect of driver strategies on traffic flow. The resulting model inherits the realistic dynamics achieved by a two-lane traffic model and aims to incorporate phenomena caused by driver-driver interactions. To achieve this goal, a game-theoretic description of driver interaction was developed. This game-theoretic formalization allows one to model different lane-changing behaviors and to keep track of mobility performance. We simulate the evolution of cooperation, traffic flow, and mobility performance for different modeled behaviors. The analysis of these results indicates a mobility optimization process achieved by drivers' interactions.

  10. Heteroduplex DNA position defines the roles of the Sgs1, Srs2, and Mph1 helicases in promoting distinct recombination outcomes.

    Directory of Open Access Journals (Sweden)

    Katrina Mitchel

    Full Text Available The contributions of the Sgs1, Mph1, and Srs2 DNA helicases during mitotic double-strand break (DSB repair in yeast were investigated using a gap-repair assay. A diverged chromosomal substrate was used as a repair template for the gapped plasmid, allowing mismatch-containing heteroduplex DNA (hDNA formed during recombination to be monitored. Overall DSB repair efficiencies and the proportions of crossovers (COs versus noncrossovers (NCOs were determined in wild-type and helicase-defective strains, allowing the efficiency of CO and NCO production in each background to be calculated. In addition, the products of individual NCO events were sequenced to determine the location of hDNA. Because hDNA position is expected to differ depending on whether a NCO is produced by synthesis-dependent-strand-annealing (SDSA or through a Holliday junction (HJ-containing intermediate, its position allows the underlying molecular mechanism to be inferred. Results demonstrate that each helicase reduces the proportion of CO recombinants, but that each does so in a fundamentally different way. Mph1 does not affect the overall efficiency of gap repair, and its loss alters the CO-NCO by promoting SDSA at the expense of HJ-containing intermediates. By contrast, Sgs1 and Srs2 are each required for efficient gap repair, strongly promoting NCO formation and having little effect on CO efficiency. hDNA analyses suggest that all three helicases promote SDSA, and that Sgs1 and Srs2 additionally dismantle HJ-containing intermediates. The hDNA data are consistent with the proposed role of Sgs1 in the dissolution of double HJs, and we propose that Srs2 dismantles nicked HJs.

  11. Traffic forecasts ignoring induced demand

    DEFF Research Database (Denmark)

    Næss, Petter; Nicolaisen, Morten Skou; Strand, Arvid

    2012-01-01

    the model calculations included only a part of the induced traffic, the difference in cost-benefit results compared to the model excluding all induced traffic was substantial. The results show lower travel time savings, more adverse environmental impacts and a considerably lower benefitcost ratio when...... induced traffic is partly accounted for than when it is ignored. By exaggerating the economic benefits of road capacity increase and underestimating its negative effects, omission of induced traffic can result in over-allocation of public money on road construction and correspondingly less focus on other...... performance of a proposed road project in Copenhagen with and without short-term induced traffic included in the transport model. The available transport model was not able to include long-term induced traffic resulting from changes in land use and in the level of service of public transport. Even though...

  12. Apparatus for obtaining electric energy in speed highways

    International Nuclear Information System (INIS)

    Khalatyan, P.R.; Khalatyan, R.P.; Khalatyan, E.P.

    2012-01-01

    The problems of obtaining electricity by means of moving motor-transport are examined. An apparatus installed in the distributive zone of intensive traffic speed highways is proposed. Part of air mass movement of kinetic energy is transformed from the movement of automobiles into electricity

  13. Soil Heavy Metal Concentration Patterns at Two Speed Zones along ...

    African Journals Online (AJOL)

    Soil Heavy Metal Concentration Patterns at Two Speed Zones along the Gaborone- Tlokweng Border Post Highway, Southeast Botswana. ... Since 1988 Botswana has been experiencing an unprecedented increase in vehicular traffic which is suspected to be having contamination effects on soils along heavily used roads ...

  14. Measures for speed management.

    NARCIS (Netherlands)

    2009-01-01

    Measures for speed management are essential for limiting the negative effects of driving too fast and at inappropriate speeds. To begin with, safe and credible speed limits need to be determined. Dynamic and variable speed limits that take into account the current circumstances, such as weather

  15. Traffic accidents: an econometric investigation

    OpenAIRE

    Tito Moreira; Adolfo Sachsida; Loureiro Paulo

    2004-01-01

    Based on a sample of drivers in Brasilia's streets, this article investigates whether distraction explains traffic accidents. A probit model is estimated to determine the predictive power of several variables on traffic accidents. The main conclusion drawn from this study is that the proxies used to measure distraction, such as the use of cell phones and cigarette smoking in a moving vehicle, are significant factors in determining traffic accidents.

  16. OPTIMASI BANDWITH MENGGUNAKAN TRAFFIC SHAPPING

    Directory of Open Access Journals (Sweden)

    Imam Riadi

    2010-01-01

    Full Text Available Perkembangan layanan komunikasi telah berkembang sangat pesat. Salah satunya adalah pemanfaatan penggunaan bandwith untuk mengakases jaringan Internet. Traffic shapping bandwidth dapat memberikan efesiensi dalam hal pemanfaatan bandwidth pada instansi yang melakukan manajemen dalam lalulintas jaringannya. Metode yang digunakan dalam penelitian ini adalah metode literatur yaitu metode pengumpulan data yang dilakukan dengan mengumpulkan sumber- sumber data yang terkait dan metode eksperimen yaitu melakukan penelitian dengan mengkonfigurasi Mikrotik RouterOS untuk melakukan traffic shapping bandwidth. Hasil penelitian ini adalah router yang dapat melakukan traffic shapping sehingga kualitas koneksi menjadi lebih baik untuk mengakses dan mengambil data dari sebuah website. Kata kunci : Optimasi, Bandwith, Traffic Shapping, MikroTik. 

  17. Bicycle traffic in urban areas

    Directory of Open Access Journals (Sweden)

    Anđelković Zorica

    2015-01-01

    Full Text Available Cycling is a term describing the use of bicycles, but also any mean of transport driven solely by human power. Development of bicycle traffic in urban areas involves construction of cycling infrastructure, adapting streets and other traffic infrastructure to a form suitable for cycling and other means of transport (individual motorized traffic, public transport, walking, ensuring the adequate budget and systematic planning and development of sustainable transport in cities. The paper presents basic settings and conditions as input elements to plan bicycle traffic in urban areas, as well as program- design conditions which lead the activities of planners and designers of urban roads in connection with cyclists.

  18. Effects of Pay-As-You-Drive vehicle insurance on young drivers' speed choice : Results of a Dutch field experiment

    NARCIS (Netherlands)

    Bolderdijk, J.W.; Knockaert, J.; Steg, L.; Verhoef, E.T.

    Speeding is an important cause for young drivers' involvement in traffic accidents. A reduction in driving speeds of this group could result in fewer accidents. One way of reducing driving speed is offering explicit financial incentives. In collaboration with five Dutch car insurance companies, we

  19. Road traffic noise prediction model for heterogeneous traffic based on ASJ-RTN Model 2008 with consideration of horn

    Science.gov (United States)

    Hustim, M.; Arifin, Z.; Aly, S. H.; Ramli, M. I.; Zakaria, R.; Liputo, A.

    2018-04-01

    This research aimed to predict the noise produced by the traffic in the road network in Makassar City using ASJ-RTN Model 2008 by calculating the horn sound. Observations were taken at 37 survey points on road side. The observations were conducted at 06.00 - 18.00 and 06.00 - 21.00 which research objects were motorcycle (MC), light vehicle (LV) and heavy vehicle (HV). The observed data were traffic volume, vehicle speed, number of horn and traffic noise using Sound Level Meter Tenmars TM-103. The research result indicates that prediction noise model by calculating the horn sound produces the average noise level value of 78.5 dB having the Pearson’s correlation and RMSE of 0.95 and 0.87. Therefore, ASJ-RTN Model 2008 prediction model by calculating the horn sound is said to be sufficiently good for predicting noise level.

  20. SELECTED PROBLEMS OF PROTECTION AGAINST ROAD TRAFFIC NOISE

    Directory of Open Access Journals (Sweden)

    Władysław Gardziejczyk

    2015-11-01

    Full Text Available The paper presents factors for assessment of road traffic noise level and possible actions towards the minimization of excessive noise in the roadway neighborhood. Changes of equivalent sound level values were analyzed in relation to traffic intensity, categorization and vehicles speed. In relation to measures reducing noise level in roadway’s surroundings particular attention was given to anti-noise protections and tyre/noise reduction. Acoustic effectiveness of specific solutions was showed based on chosen examples. It was proved that when admissible noise level is slightly exceeded the need for noise barrier use may be replaced by a proper design and maintenance of road pavement or by enforcement of speed limit.

  1. The Pattern of Road Traffic Crashes in South East Iran.

    Science.gov (United States)

    Rad, Mahdieh; Martiniuk, Alexandra Lc; Ansari-Moghaddam, Alireza; Mohammadi, Mahdi; Rashedi, Fariborz; Ghasemi, Ardavan

    2016-09-01

    In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. This cross-sectional study included the profile of 2398 motor vehicle crashes recorded in the police office in one Year in South East of Iran. Data collected included: demographics, the type of crash, type of involved vehicle, location of crash and factors contributing to the crash. Descriptive statistics were used for data analysis. Collisions with other vehicles or objects contributed the highest proportion (62.4%) of motor vehicle crashes. Human factors including careless driving, violating traffic laws, speeding, and sleep deprivation/fatigue were the most important causal factors accounting for 90% of road crashes. Data shows that 41% of drivers were not using a seat belt at the time of crash. One- third of the crashes resulted in injury (25%) or death (5%). Reckless driving such as speeding and violation of traffic laws are major risk factors for crashes in the South East of Iran. This highlights the need for education along with traffic law enforcement to reduce motor vehicle crashes in future.

  2. Traffic simulation for mixed traffic systems | Mbam | Global Journal of ...

    African Journals Online (AJOL)

    Traffic problem is classified into single and mixed, especially in most developing countries, where motorbikes are used as the most popular transportation system. The aim of this paper is to introduce the motorbike symbol into the traffic light control system to separate cars/lorries indicator from that of motorbike. This is likely ...

  3. Traffic Infrastructure in the Development of the Croatian Traffic System

    Directory of Open Access Journals (Sweden)

    Damir Šimulčik

    2012-10-01

    Full Text Available The absence of a long-term traffic policy and of the policyof financing the constntction and maintenance of traffic infrastructurefacilities, represents a synthesis of numerous unresolvedrelations whose negative effects are felt in the overalleconomic and traffic development and consequently theevaluation of national potentials in the field. Adverse aspectcaused by the lack of a clear and feasible policy of financing thetraffic infrastructure facilities, is also a result of not having definedan adequate traffic policy, programme and strategiccourses of development, nor financing models that would be inaccordance with the market and economy system.This indicates that it is necessary to determine a policy forfinancing the constntction and maintenance of traffic infrastntcture,which has to be based on scientific development,team work, availability of plans and programmes to scientistsand experts, determined methodology based on marketing andeconomic logic in defining the programme and strategic tasksand assignments so as to make them feasible.In the near future, intensive preparations for investments inthe overall traffic sysiem are necessary, especially regarding thetraffic infrastntcture facilities - the pivotal points in the processof evaluating the traffic in our national tenitory. Croatia needsto define clearly its strategy in constructing and maintaining thegeneral traffic infrastructure, appointing at the same time thosewho will carry out the given tasks.

  4. Real time traffic models, decision support for traffic management

    NARCIS (Netherlands)

    Wismans, Luc Johannes Josephus; de Romph, E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various

  5. Real Time Traffic Models, Decision Support for Traffic Management

    NARCIS (Netherlands)

    Wismans, L.; De Romph, E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various

  6. AT89S52 Microcontroller Based A Speed Restraint Equipment for Motorcycle

    Directory of Open Access Journals (Sweden)

    Ikhsan hidayat

    2009-08-01

    Full Text Available Security riding is very important in the aspects of traffic. One of the main factors of traffic accidents is high speed. Therefore, it is required a speed restraint equipment for pressing the number of accidents. The car speed restraint system is available in the market, but on a motorcycle is not available yet. This paper presents a design of speed restraint equipment for motorcycle that safe for users, and is expected to reduce traffic accident. The Main idea this speed restriction is cutting off the flow of electrical signals from the pulser (the time ignition trigger sensor to the CDI for 1 second. The cutting Signal with mechanical relays controlled by microcontroller AT89S52 using the on-off algorithm. Speed sensor use optocoupler is used to detect the number of rounds wheel motorcycle. If a result of measurement is more than the speed setpoint, microcontroler make a decission to cut motorcycle ignition signal. Results of this research is a prototype speed restraint shown that it able to process data from the measurement of the speed limit on the speed of a motorcycle. This prototype safe for all users and accordance with the set value and the level of success is above 90% for speed of 10 km/hr to 40 km/hr.

  7. Alleviating Traffic Congestion in Manila, Appraisal of the Pasig Expressway

    OpenAIRE

    Glenn Jenkins; BAHER EL-HIFNAWI

    2002-01-01

    Travel in Metro Manila at present is characterized by high levels of congestion, slow travel speeds, long journey times and limited road capacity. The situation will be further exacerbated due to the expected growth in population and income and the subsequent increase in car ownership. Localized traffic management schemes are no longer sufficient to solve the problem. Solutions on the demand side curbing the demand for car ownership and use should be considered together with solutions on the ...

  8. System level traffic shaping in disk servers with heterogeneous protocols

    International Nuclear Information System (INIS)

    Cano, Eric; Kruse, Daniele Francesco

    2014-01-01

    Disk access and tape migrations compete for network bandwidth in CASTORs disk servers, over various protocols: RFIO, Xroot, root and GridFTP. As there are a limited number of tape drives, it is important to keep them busy all the time, at their nominal speed. With potentially 100s of user read streams per server, the bandwidth for the tape migrations has to be guaranteed to a controlled level, and not the fair share the system gives by default. Xroot provides a prioritization mechanism, but using it implies moving exclusively to the Xroot protocol, which is not possible in short to mid-term time frame, as users are equally using all protocols. The greatest commonality of all those protocols is not more than the usage of TCP/IP. We investigated the Linux kernel traffic shaper to control TCP/ IP bandwidth. The performance and limitations of the traffic shaper have been understood in test environment, and satisfactory working point has been found for production. Notably, TCP offload engines' negative impact on traffic shaping, and the limitations of the length of the traffic shaping rules were discovered and measured. A suitable working point has been found and the traffic shaping is now successfully deployed in the CASTOR production systems at CERN. This system level approach could be transposed easily to other environments.

  9. Phase transition in traffic jam experiment on a circuit

    International Nuclear Information System (INIS)

    Tadaki, Shin-ichi; Kikuchi, Macoto; Fukui, Minoru; Yosida, Taturu; Nakayama, Akihiro; Nishinari, Katsuhiro; Shibata, Akihiro; Sugiyama, Yuki; Yukawa, Satoshi

    2013-01-01

    The emergence of a traffic jam is considered to be a dynamical phase transition in a physics point of view; traffic flow becomes unstable and changes phase into a traffic jam when the car density exceeds a critical value. In order to verify this view, we have been performing a series of circuit experiments. In our previous work (2008 New J. Phys. 10 033001), we demonstrated that a traffic jam emerges even in the absence of bottlenecks at a certain high density. In this study, we performed a larger indoor circuit experiment in the Nagoya Dome in which the positions of cars were observed using a high-resolution laser scanner. Over a series of sessions at various values of density, we found that jammed flow occurred at high densities, whereas free flow was conserved at low densities. We also found indications of metastability at an intermediate density. The critical density is estimated by analyzing the fluctuations in speed and the density–flow relation. The value of this critical density is consistent with that observed on real expressways. This experiment provides strong support for physical interpretations of the emergence of traffic jams as a dynamical phase transition. (paper)

  10. Road traffic safety in conjunction with in-vehicle ITS

    Directory of Open Access Journals (Sweden)

    Darja TOPOLŠEK

    2014-06-01

    Full Text Available Interest in Intelligent Transportation Systems comes from the problems caused by traffic congestion, road accidents and air pollution. Traffic congestion continues to grow worldwide as a result of increased motorization, population growth, changes in population density and urbanization. Interest in ITS can also be attributed to reducing road accidents and increasing traffic safety. The most common causes for road accidents are excessive speed, inattentive driving and ignorance of the right-of-way rules. To eliminate these causes, experience, knowledge of traffic regulations and a new car are not enough – vehicle safety systems have to take part as well. Therefore, the European Union issued a directive on the installation of intelligent systems, whose functions are active support during driving, warning the driver in dangerous situations and alerting passengers of the car in case of irregularities in motor function or actions carried out by the driver that may cause danger, such as swerving while falling asleep. These systems help drivers to avoid accidents, and in the event of a collision, an emergency call is automatically made. Furthermore, they can be used to regulate traffic patterns or to reduce engine performance, which would reduce pollution. With these benefits in mind, the EU has indicated to the automotive industry that installation of these new Intelligent Transportation Systems should be mandatory in their new vehicles.

  11. Spatiotemporal Recurrent Convolutional Networks for Traffic Prediction in Transportation Networks

    Directory of Open Access Journals (Sweden)

    Haiyang Yu

    2017-06-01

    Full Text Available Predicting large-scale transportation network traffic has become an important and challenging topic in recent decades. Inspired by the domain knowledge of motion prediction, in which the future motion of an object can be predicted based on previous scenes, we propose a network grid representation method that can retain the fine-scale structure of a transportation network. Network-wide traffic speeds are converted into a series of static images and input into a novel deep architecture, namely, spatiotemporal recurrent convolutional networks (SRCNs, for traffic forecasting. The proposed SRCNs inherit the advantages of deep convolutional neural networks (DCNNs and long short-term memory (LSTM neural networks. The spatial dependencies of network-wide traffic can be captured by DCNNs, and the temporal dynamics can be learned by LSTMs. An experiment on a Beijing transportation network with 278 links demonstrates that SRCNs outperform other deep learning-based algorithms in both short-term and long-term traffic prediction.

  12. Phase transition in traffic jam experiment on a circuit

    Science.gov (United States)

    Tadaki, Shin-ichi; Kikuchi, Macoto; Fukui, Minoru; Nakayama, Akihiro; Nishinari, Katsuhiro; Shibata, Akihiro; Sugiyama, Yuki; Yosida, Taturu; Yukawa, Satoshi

    2013-10-01

    The emergence of a traffic jam is considered to be a dynamical phase transition in a physics point of view; traffic flow becomes unstable and changes phase into a traffic jam when the car density exceeds a critical value. In order to verify this view, we have been performing a series of circuit experiments. In our previous work (2008 New J. Phys. 10 033001), we demonstrated that a traffic jam emerges even in the absence of bottlenecks at a certain high density. In this study, we performed a larger indoor circuit experiment in the Nagoya Dome in which the positions of cars were observed using a high-resolution laser scanner. Over a series of sessions at various values of density, we found that jammed flow occurred at high densities, whereas free flow was conserved at low densities. We also found indications of metastability at an intermediate density. The critical density is estimated by analyzing the fluctuations in speed and the density-flow relation. The value of this critical density is consistent with that observed on real expressways. This experiment provides strong support for physical interpretations of the emergence of traffic jams as a dynamical phase transition.

  13. Drivers' perceptions regarding speeding and driving on urban residential streets with a 30 km/h speed limit

    Directory of Open Access Journals (Sweden)

    Do Duy Dinh

    2013-07-01

    Full Text Available Previous studies have shown very little information regarding drivers' opinions, attitudes and behaviours with respect to speeding and driving on urban residential streets with a 30 km/h speed limit. The present research aims to address this issue by conducting a questionnaire study with a sample of 367 Japanese drivers. The results showed that drivers tended to have positive beliefs about complying with the 30 km/h speed limit and understand the negative consequences of speeding; however, a majority of the drivers considered breaking the speed limit as a way to reduce their travel time. While the extent of speeding was found to be very serious, a number of drivers still supported the use of a 30 km/h speed limit on residential streets and favoured protecting the right of vulnerable street users. The logistic regression models developed in this study identified that the drivers who did not support the 30 km/h speed limit were associated with those who had committed traffic-law violations, who had negative beliefs about complying with the speed limit, who did not consider residents' opinions, who believed it is acceptable for them to drive at a high speed, and who felt it difficult to refrain from speeding. With regard to anti-speeding countermeasures, under drivers' point of view, streets should be designed to make the 30 km/h speed limit more credible, although this study also showed evidence supporting the application of public awareness programmes and social campaigns as speeding interventions. In addition, this research investigated drivers' speed choices in various specific driving circumstances, and six underlying factors affecting drivers' speed choices were determined. On the basic of the findings, the implications and suggestions for speeding interventions were also discussed.

  14. Reports on internet traffic statistics

    NARCIS (Netherlands)

    Hoogesteger, Martijn; de Oliveira Schmidt, R.; Sperotto, Anna; Pras, Aiko

    2013-01-01

    Internet traffic statistics can provide valuable information to network analysts and researchers about the way nowadays networks are used. In the past, such information was provided by Internet2 in a public website called Internet2 NetFlow: Weekly Reports. The website reported traffic statistics

  15. Probabilistic description of traffic flow

    International Nuclear Information System (INIS)

    Mahnke, R.; Kaupuzs, J.; Lubashevsky, I.

    2005-01-01

    A stochastic description of traffic flow, called probabilistic traffic flow theory, is developed. The general master equation is applied to relatively simple models to describe the formation and dissolution of traffic congestions. Our approach is mainly based on spatially homogeneous systems like periodically closed circular rings without on- and off-ramps. We consider a stochastic one-step process of growth or shrinkage of a car cluster (jam). As generalization we discuss the coexistence of several car clusters of different sizes. The basic problem is to find a physically motivated ansatz for the transition rates of the attachment and detachment of individual cars to a car cluster consistent with the empirical observations in real traffic. The emphasis is put on the analogy with first-order phase transitions and nucleation phenomena in physical systems like supersaturated vapour. The results are summarized in the flux-density relation, the so-called fundamental diagram of traffic flow, and compared with empirical data. Different regimes of traffic flow are discussed: free flow, congested mode as stop-and-go regime, and heavy viscous traffic. The traffic breakdown is studied based on the master equation as well as the Fokker-Planck approximation to calculate mean first passage times or escape rates. Generalizations are developed to allow for on-ramp effects. The calculated flux-density relation and characteristic breakdown times coincide with empirical data measured on highways. Finally, a brief summary of the stochastic cellular automata approach is given

  16. Particle-based model for skiing traffic.

    Science.gov (United States)

    Holleczek, Thomas; Tröster, Gerhard

    2012-05-01

    We develop and investigate a particle-based model for ski slope traffic. Skiers are modeled as particles with a mass that are exposed to social and physical forces, which define the riding behavior of skiers during their descents on ski slopes. We also report position and speed data of 21 skiers recorded with GPS-equipped cell phones on two ski slopes. A comparison of these data with the trajectories resulting from computer simulations of our model shows a good correspondence. A study of the relationship among the density, speed, and flow of skiers reveals that congestion does not occur even with arrival rates of skiers exceeding the maximum ski lift capacity. In a sensitivity analysis, we identify the kinetic friction coefficient of skis on snow, the skier mass, the range of repelling social forces, and the arrival rate of skiers as the crucial parameters influencing the simulation results. Our model allows for the prediction of speed zones and skier densities on ski slopes, which is important in the prevention of skiing accidents.

  17. Lane changing and speed interaction on freeways : An analytical microscopic study

    NARCIS (Netherlands)

    Keyvan Ekbatani, M.; Grebert, V.; Daamen, W.; Knoop, V.L.

    2015-01-01

    Understanding the influence of lane changing manoeuvre on the capacity, stability, and breakdown of traffic flows is a crucial issue. In a recent study, four distinct lane change strategies on freeways have been empirically found: (1) Speed Leading; (2) Speed Leading with Overtaking; (3) Lane

  18. Work zone variable speed limit systems: Effectiveness and system design issues.

    Science.gov (United States)

    2010-03-01

    Variable speed limit (VSL) systems have been used in a number of countries, particularly in Europe, as a method to improve flow and increase safety. VSLs use detectors to collect data on current traffic and/or weather conditions. Posted speed limits ...

  19. Area-wide traffic calming for preventing traffic related injuries.

    Science.gov (United States)

    Bunn, F; Collier, T; Frost, C; Ker, K; Roberts, I; Wentz, R

    2003-01-01

    It is estimated that by 2020 road traffic crashes will have moved from ninth to third in the world disease burden ranking, as measured in disability adjusted life years, and second in developing countries. The identification of effective strategies for the prevention of traffic related injuries is of global health importance. Area-wide traffic calming schemes that discourage through traffic on residential roads is one such strategy. To evaluate the effectiveness of area-wide traffic calming in preventing traffic related crashes, injuries, and deaths. We searched the following electronic databases: Cochrane Injuries Group's Specialised Register, Cochrane Controlled Trials Register, MEDLINE, EMBASE and TRANSPORT (NTIS, TRIS, TRANSDOC). We searched the web sites of road safety organisations, handsearched conference proceedings, checked reference lists of relevant papers and contacted experts in the area. The search was not restricted by language or publication status. Randomised controlled trials, and controlled before-after studies of area-wide traffic calming schemes. Two reviewers independently extracted data on type of study, characteristics of intervention and control areas, and length of data collection periods. Before and after data were collected on the total number of road traffic crashes, all road user deaths and injuries, pedestrian-motor vehicle collisions and road user deaths. The statistical package STATA was used to calculate rate ratios for each study, which were then pooled to give an overall estimate using a random effects model. We found no randomised controlled trials, but 16 controlled before-after trials met our inclusion criteria. Seven studies were done in Germany, six in the UK, two in Australia and one in the Netherlands. There were no studies in low or middle income countries. Eight trials reported the number of road traffic crashes resulting in deaths. The pooled rate ratio was 0.63 (0.14, 2.59 95% CI). Sixteen studies reported the number

  20. Photonics approach to traffic signs

    Science.gov (United States)

    Litwin, Dariusz; Galas, Jacek; CzyŻewski, Adam; Rymsza, Barbara; Kornalewski, Leszek; Kryszczyński, Tadeusz; Mikucki, Jerzy; Wikliński, Piotr; Daszkiewicz, Marek; Malasek, Jacek

    2016-12-01

    The automotive industry has been always a driving force for all economies. Despite of its beneficial meaning to every society it brings also many issues including wide area of road safety. The latter has been enforced by the increasing number of cars and the dynamic development of the traffic as a whole. Road signs and traffic lights are crucial in context of good traffic arrangement and its fluency. Traffic designers are used to treat horizontal road signs independently of vertical signs. However, modern light sources and growing flexibility in shaping optical systems create opportunity to design more advanced and smart solutions. In this paper we present an innovative, multidisciplinary approach that consists in tight interdependence of different traffic signals. We describe new optical systems together with their influence on the perception of the road user. The analysis includes maintenance and visibility in different weather conditions. A special attention has been focused on intersections of complex geometry.

  1. Dissociative Tendencies and Traffic Incidents

    Directory of Open Access Journals (Sweden)

    Valle, Virginia

    2012-01-01

    Full Text Available This paper analyses the relationship between dissociative experiences and road traffic incidents (crashes and traffic tickets in drivers (n=295 from Mar del Plata (Argentina city. A self-report questionnaire was applied to assess traffic crash involvement and sociodemographic variables. Dissociative tendencies were assessed by a modified version of the DES scale. To examine differences in DES scores tests of the difference of means were applied. Drivers who reported to be previously involved in traffic incidents obtained higher puntuations in the dissociative experiences scale than drivers who did not report such events. This result is observed for the total scale and for the three sub-scales (absorption, amnesia and depersonalization. However, differences appeared mainly for minor damage collisions. Further studies are needed to evaluate the role of dissociative tendencies as a risk factor in road traffic safety.

  2. Model for traffic emissions estimation

    Science.gov (United States)

    Alexopoulos, A.; Assimacopoulos, D.; Mitsoulis, E.

    A model is developed for the spatial and temporal evaluation of traffic emissions in metropolitan areas based on sparse measurements. All traffic data available are fully employed and the pollutant emissions are determined with the highest precision possible. The main roads are regarded as line sources of constant traffic parameters in the time interval considered. The method is flexible and allows for the estimation of distributed small traffic sources (non-line/area sources). The emissions from the latter are assumed to be proportional to the local population density as well as to the traffic density leading to local main arteries. The contribution of moving vehicles to air pollution in the Greater Athens Area for the period 1986-1988 is analyzed using the proposed model. Emissions and other related parameters are evaluated. Emissions from area sources were found to have a noticeable share of the overall air pollution.

  3. Control of ribosome traffic by position-dependent choice of synonymous codons

    DEFF Research Database (Denmark)

    Mitarai, Namiko; Pedersen, Steen

    2013-01-01

    Messenger RNA (mRNA) encodes a sequence of amino acids by using codons. For most amino acids, there are multiple synonymous codons that can encode the amino acid. The translation speed can vary from one codon to another, thus there is room for changing the ribosome speed while keeping the amino...... acid sequence and hence the resulting protein. Recently, it has been noticed that the choice of the synonymous codon, via the resulting distribution of slow- and fast-translated codons, affects not only on the average speed of one ribosome translating the mRNA but also might have an effect on nearby...... ribosomes by affecting the appearance of 'traffic jams' where multiple ribosomes collide and form queues. To test this 'context effect' further, we here investigate the effect of the sequence of synonymous codons on the ribosome traffic by using a ribosome traffic model with codon-dependent rates, estimated...

  4. Kinetic energy management in road traffic injury prevention: a call for action

    Directory of Open Access Journals (Sweden)

    Davoud Khorasani-Zavareh

    2015-01-01

    Full Text Available Abstract: By virtue of their variability, mass and speed have important roles in transferring energies during a crash incidence (kinetic energy. The sum of kinetic energy is important in determining an injury severity and that is equal to one half of the vehicle mass multiplied by the square of the vehicle speed. To meet the Vision Zero policy (a traffic safety policy prevention activities should be focused on vehicle speed management. Understanding the role of kinetic energy will help to develop measures to reduce the generation, distribution, and effects of this energy during a road traffic crash. Road traffic injury preventive activities necessitate Kinetic energy management to improve road user safety.

  5. A new smart traffic monitoring method using embedded cement-based piezoelectric sensors

    International Nuclear Information System (INIS)

    Zhang, Jinrui; Lu, Youyuan; Lu, Zeyu; Liu, Chao; Sun, Guoxing; Li, Zongjin

    2015-01-01

    Cement-based piezoelectric composites are employed as the sensing elements of a new smart traffic monitoring system. The piezoelectricity of the cement-based piezoelectric sensors enables powerful and accurate real-time detection of the pressure induced by the traffic flow. To describe the mechanical-electrical conversion mechanism between traffic flow and the electrical output of the embedded piezoelectric sensors, a mathematical model is established based on Duhamel’s integral, the constitutive law and the charge-leakage characteristics of the piezoelectric composite. Laboratory tests show that the voltage magnitude of the sensor is linearly proportional to the applied pressure, which ensures the reliability of the cement-based piezoelectric sensors for traffic monitoring. A series of on-site road tests by a 10 tonne truck and a 6.8 tonne van show that vehicle weight-in-motion can be predicted based on the mechanical-electrical model by taking into account the vehicle speed and the charge-leakage property of the piezoelectric sensor. In the speed range from 20 km h −1 to 70 km h −1 , the error of the repeated weigh-in-motion measurements of the 6.8 tonne van is less than 1 tonne. The results indicate that the embedded cement-based piezoelectric sensors and associated measurement setup have good capability of smart traffic monitoring, such as traffic flow detection, vehicle speed detection and weigh-in-motion measurement. (paper)

  6. Simple cellular automaton model for traffic breakdown, highway capacity, and synchronized flow

    Science.gov (United States)

    Kerner, Boris S.; Klenov, Sergey L.; Schreckenberg, Michael

    2011-10-01

    We present a simple cellular automaton (CA) model for two-lane roads explaining the physics of traffic breakdown, highway capacity, and synchronized flow. The model consists of the rules “acceleration,” “deceleration,” “randomization,” and “motion” of the Nagel-Schreckenberg CA model as well as “overacceleration through lane changing to the faster lane,” “comparison of vehicle gap with the synchronization gap,” and “speed adaptation within the synchronization gap” of Kerner's three-phase traffic theory. We show that these few rules of the CA model can appropriately simulate fundamental empirical features of traffic breakdown and highway capacity found in traffic data measured over years in different countries, like characteristics of synchronized flow, the existence of the spontaneous and induced breakdowns at the same bottleneck, and associated probabilistic features of traffic breakdown and highway capacity. Single-vehicle data derived in model simulations show that synchronized flow first occurs and then self-maintains due to a spatiotemporal competition between speed adaptation to a slower speed of the preceding vehicle and passing of this slower vehicle. We find that the application of simple dependences of randomization probability and synchronization gap on driving situation allows us to explain the physics of moving synchronized flow patterns and the pinch effect in synchronized flow as observed in real traffic data.

  7. The NASA Air Traffic Management Ontology (atmonto)

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA ATM (Air Traffic Management) Ontology describes classes, properties, and relationships relevant to the domain of air traffic management, and represents...

  8. Traffic information computing platform for big data

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn; Liu, Yan, E-mail: ztduan@chd.edu.cn; Dai, Jiting, E-mail: ztduan@chd.edu.cn; Kang, Jun, E-mail: ztduan@chd.edu.cn [Chang' an University School of Information Engineering, Xi' an, China and Shaanxi Engineering and Technical Research Center for Road and Traffic Detection, Xi' an (China)

    2014-10-06

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users.

  9. Traffic information computing platform for big data

    International Nuclear Information System (INIS)

    Duan, Zongtao; Li, Ying; Zheng, Xibin; Liu, Yan; Dai, Jiting; Kang, Jun

    2014-01-01

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users

  10. A Novel Multisensor Traffic State Assessment System Based on Incomplete Data

    Directory of Open Access Journals (Sweden)

    Yiliang Zeng

    2014-01-01

    Full Text Available A novel multisensor system with incomplete data is presented for traffic state assessment. The system comprises probe vehicle detection sensors, fixed detection sensors, and traffic state assessment algorithm. First of all, the validity checking of the traffic flow data is taken as preprocessing of this method. And then a new method based on the history data information is proposed to fuse and recover the incomplete data. According to the characteristics of space complementary of data based on the probe vehicle detector and fixed detector, a fusion model of space matching is presented to estimate the mean travel speed of the road. Finally, the traffic flow data include flow, speed and, occupancy rate, which are detected between Beijing Deshengmen bridge and Drum Tower bridge, are fused to assess the traffic state of the road by using the fusion decision model of rough sets and cloud. The accuracy of experiment result can reach more than 98%, and the result is in accordance with the actual road traffic state. This system is effective to assess traffic state, and it is suitable for the urban intelligent transportation system.

  11. Exploiting Spatial Abstraction in Predictive Analytics of Vehicle Traffic

    Directory of Open Access Journals (Sweden)

    Natalia Andrienko

    2015-04-01

    Full Text Available By applying visual analytics techniques to vehicle traffic data, we found a way to visualize and study the relationships between the traffic intensity and movement speed on links of a spatially abstracted transportation network. We observed that the traffic intensities and speeds in an abstracted network are interrelated in the same way as they are in a detailed street network at the level of street segments. We developed interactive visual interfaces that support representing these interdependencies by mathematical models. To test the possibility of utilizing them for performing traffic simulations on the basis of abstracted transportation networks, we devised a prototypical simulation algorithm employing these dependency models. The algorithm is embedded in an interactive visual environment for defining traffic scenarios, running simulations, and exploring their results. Our research demonstrates a principal possibility of performing traffic simulations on the basis of spatially abstracted transportation networks using dependency models derived from real traffic data. This possibility needs to be comprehensively investigated and tested in collaboration with transportation domain specialists.

  12. Studies of vehicle lane-changing dynamics and its effect on traffic efficiency, safety and environmental impact

    Science.gov (United States)

    Li, Xiang; Sun, Jian-Qiao

    2017-02-01

    Drivers often change lanes on the road to maintain desired speed and to avoid slow vehicles, pedestrians, obstacles and lane closure. Understanding the effect of lane-changing on the traffic is an important topic in designing optimal traffic control systems. This paper presents a comprehensive study of this topic. We review the theory of microscopic dynamic car-following models and the lane-changing models, propose additional lane-changing rules to deal with moving bottleneck and lane reduction, and investigate the effects of lane-changing on the traffic efficiency, traffic safety and fuel consumption as a function of different variables including the distance of the emergency sign ahead of the lane closure, speed limit, traffic density, etc. Extensive simulations of the traffic system have been carried out in different scenarios. A number of important findings of the effect of various factors on the traffic are reported. These findings provide guidance on the traffic management and are important to the designers and engineers of modern highway or inner city roads to achieve high traffic efficiency and safety with minimum environmental impact.

  13. Speed management program plan.

    Science.gov (United States)

    2014-05-01

    Changing public attitudes regarding speeding and speed management will require a comprehensive and concerted effort, involving a wide variety of strategies. This plan identifies six primary focus areas: : A. Data and Data-Driven Approaches, : B. Rese...

  14. Small portable speed calculator

    Science.gov (United States)

    Burch, J. L.; Billions, J. C.

    1973-01-01

    Calculator is adapted stopwatch calibrated for fast accurate measurement of speeds. Single assembled unit is rugged, self-contained, and relatively inexpensive to manufacture. Potential market includes automobile-speed enforcement, railroads, and field-test facilities.

  15. Electric vehicle speed control

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, W.R.; Mc Auliffe, G.N.; Schlageter, G.A.

    1987-06-23

    This patent describes an electric vehicle driven by a DC motor. The vehicle has a field winding, an electric resistance element in circuit with the field winding, a switch in the circuit operative when closed to place. The element in parallel with the field winding weakens the field and increases potential motor speed. Also are relay means for operating the switch, means to determine motor speed, computer means for determining whether the motor speed is increasing or decreasing, and means for operating the relay means to close the switch at a first speed. If the motor speed is increased, it actuates the switch at a second speed lower than the first speed but only if switch has been closed previously and motor speed is decreasing.

  16. Characterizing Traffic Conditions from the Perspective of Spatial-Temporal Heterogeneity

    Directory of Open Access Journals (Sweden)

    Peichao Gao

    2016-03-01

    Full Text Available Traffic conditions are usually characterized from the perspective of travel time or the average vehicle speed in the field of transportation, reflecting the congestion degree of a road network. This article provides a method from a new perspective to characterize traffic conditions; the perspective is based on the heterogeneity of vehicle speeds. A novel measurement, the ratio of areas (RA in a rank-size plot, is included in the proposed method to capture the heterogeneity. The proposed method can be performed from the perspective of both spatial heterogeneity and temporal heterogeneity, being able to characterize traffic conditions of not only a road network but also a single road. Compared with methods from the perspective of travel time, the proposed method can characterize traffic conditions at a higher frequency. Compared to methods from the perspective of the average vehicle speed, the proposed method takes account of the heterogeneity of vehicle speeds. The effectiveness of the proposed method has been demonstrated with real-life traffic data of Shenzhen (a coastal urban city in China, and the advantage of the proposed RA has been verified by comparisons to similar measurements such as the ht-index and the CRG index.

  17. Knee Angle and Stride Length in Association with Ball Speed in Youth Baseball Pitchers

    Directory of Open Access Journals (Sweden)

    Bart van Trigt

    2018-05-01

    Full Text Available The purpose of this study was to determine whether stride length and knee angle of the leading leg at foot contact, at the instant of maximal external rotation of the shoulder, and at ball release are associated with ball speed in elite youth baseball pitchers. In this study, fifty-two elite youth baseball pitchers (mean age 15.2 SD (standard deviation 1.7 years pitched ten fastballs. Data were collected with three high-speed video cameras at a frequency of 240 Hz. Stride length and knee angle of the leading leg were calculated at foot contact, maximal external rotation, and ball release. The associations between these kinematic variables and ball speed were separately determined using generalized estimating equations. Stride length as percentage of body height and knee angle at foot contact were not significantly associated with ball speed. However, knee angles at maximal external rotation and ball release were significantly associated with ball speed. Ball speed increased by 0.45 m/s (1 mph with an increase in knee extension of 18 degrees at maximal external rotation and 19.5 degrees at ball release. In conclusion, more knee extension of the leading leg at maximal external rotation and ball release is associated with higher ball speeds in elite youth baseball pitchers.

  18. Comparison of Predictive Modeling Methods of Aircraft Landing Speed

    Science.gov (United States)

    Diallo, Ousmane H.

    2012-01-01

    Expected increases in air traffic demand have stimulated the development of air traffic control tools intended to assist the air traffic controller in accurately and precisely spacing aircraft landing at congested airports. Such tools will require an accurate landing-speed prediction to increase throughput while decreasing necessary controller interventions for avoiding separation violations. There are many practical challenges to developing an accurate landing-speed model that has acceptable prediction errors. This paper discusses the development of a near-term implementation, using readily available information, to estimate/model final approach speed from the top of the descent phase of flight to the landing runway. As a first approach, all variables found to contribute directly to the landing-speed prediction model are used to build a multi-regression technique of the response surface equation (RSE). Data obtained from operations of a major airlines for a passenger transport aircraft type to the Dallas/Fort Worth International Airport are used to predict the landing speed. The approach was promising because it decreased the standard deviation of the landing-speed error prediction by at least 18% from the standard deviation of the baseline error, depending on the gust condition at the airport. However, when the number of variables is reduced to the most likely obtainable at other major airports, the RSE model shows little improvement over the existing methods. Consequently, a neural network that relies on a nonlinear regression technique is utilized as an alternative modeling approach. For the reduced number of variables cases, the standard deviation of the neural network models errors represent over 5% reduction compared to the RSE model errors, and at least 10% reduction over the baseline predicted landing-speed error standard deviation. Overall, the constructed models predict the landing-speed more accurately and precisely than the current state-of-the-art.

  19. Effect Of Platooning on Fuel Consumption of Class 8 Vehicles Over a Range of Speeds, Following Distances, and Mass

    Energy Technology Data Exchange (ETDEWEB)

    Lammert, M. P.; Duran, A.; Diez, J.; Burton, K.; Nicholson, A.

    2014-10-01

    This research project evaluates fuel consumption results of two Class 8 tractor-trailer combinations platooned together compared to their standalone fuel consumption. A series of ten modified SAE Type II J1321 fuel consumption track tests were performed to document fuel consumption of two platooned vehicles and a control vehicle at varying steady-state speeds, following distances, and gross vehicle weights (GVWs). The steady-state speeds ranged from 55 mph to 70 mph, the following distances ranged from a 20-ft following distance to a 75-ft following distance, and the GVWs were 65K lbs and 80K lbs. All tractors involved had U.S. Environmental Protection Agency (EPA) SmartWay-compliant aerodynamics packages installed, and the trailers were equipped with side skirts. Effects of vehicle speed, following distance, and GVW on fuel consumption were observed and analyzed. The platooning demonstration system used in this study consisted of radar systems, Dedicated Short-Range Communication (DSRC) vehicle-to-vehicle (V2V) communications, vehicle braking and torque control interface, cameras and driver displays. The lead tractor consistently demonstrated an improvement in average fuel consumption reduction as following distance decreased, with results showing 2.7% to 5.3% fuel savings at a GVW of 65k. The trailing vehicle achieved fuel consumption savings ranging from 2.8% to 9.7%; tests during which the engine cooling fan did not operate achieved savings of 8.4% to 9.7%. 'Team' fuel savings, considering the platooned vehicles as one, ranged from 3.7% to 6.4%, with the best combined result being for 55 mph, 30-ft following distance, and 65k GVW.

  20. The Crossing Speed of Elderly Pedestrians

    Directory of Open Access Journals (Sweden)

    Ana Trpković

    2017-04-01

    Full Text Available The population of elderly people is rapidly growing and in terms of safety, senior pedestrians represent one of the most vulnerable group. The pedestrian crossing speed is a significant input parameter in traffic engineering, which can have effect on pedestrians’ safety, especially of older population. The objective of this study was to determine the value of the crossing speed of elderly pedestrians (65+ for different types of urban crossings. The research was conducted at ten intersections in the city of Belgrade, Serbia, using the method of direct observation and a questionnaire for collecting data. The data were analysed in the statistical software package IBM SPSS Statistics. The results showed that elderly pedestrians walk slower and the crossing type significantly influenced the speed of older population. The order of crossing types in relation to the measured speed is ranked as follows, from the lowest to the highest speed value: unsignalized, signalized, signalized with pedestrian countdown display, signalized with pedestrian island and pedestrian countdown display and finally signalized crossing with pedestrian island. According to the questionnaire results, the elderly recognize the importance of implementing pedestrian counters. This indicates the necessity to provide safe street crossing for the elderly using the corresponding engineering measures.

  1. Psychological Factors related to traffic accidents

    Directory of Open Access Journals (Sweden)

    Serafín Aldea Muñoz

    2002-07-01

    Full Text Available Automobile drivers fine themselves affected by series psychological factors which are directly related to traffic accidents. In this study we intend to investigate these variables, basing our work on the most convenient sources of information, coming from the police, the General Direction of Traffic, the courts, insurance companies, the Red Cross, Social Security, and forensics. Neither could we ignore the influence which certain forces hold over people´s mental health; this can sometimes intensely affect how they drive. In fact, in the most diverse situations we can observe the way in which a person carries out a task can be conditioned by the presence of other person who may have no direct relationship to him. Society has established its limitations and rules, but speed itself feels omnipotence when imposing controls over the most profound behavior in others; man in usually not conscious of these controls. People generally drive their automobiles in a way similar to their habitual behavior and their personality traits. Nevertheless, it is also important to consider the adaptation of their way of driving to their state of mind at any given moment. The majority of subjects tend to adapt their driving to their emotional state.

  2. Emergency vehicle traffic signal preemption system

    Science.gov (United States)

    Bachelder, Aaron D. (Inventor); Foster, Conrad F. (Inventor)

    2011-01-01

    An emergency vehicle traffic light preemption system for preemption of traffic lights at an intersection to allow safe passage of emergency vehicles. The system includes a real-time status monitor of an intersection which is relayed to a control module for transmission to emergency vehicles as well as to a central dispatch office. The system also provides for audio warnings at an intersection to protect pedestrians who may not be in a position to see visual warnings or for various reasons cannot hear the approach of emergency vehicles. A transponder mounted on an emergency vehicle provides autonomous control so the vehicle operator can attend to getting to an emergency and not be concerned with the operation of the system. Activation of a priority-code (i.e. Code-3) situation provides communications with each intersection being approached by an emergency vehicle and indicates whether the intersection is preempted or if there is any conflict with other approaching emergency vehicles. On-board diagnostics handle various information including heading, speed, and acceleration sent to a control module which is transmitted to an intersection and which also simultaneously receives information regarding the status of an intersection. Real-time communications and operations software allow central and remote monitoring, logging, and command of intersections and vehicles.

  3. A Two-Stage Fuzzy Logic Control Method of Traffic Signal Based on Traffic Urgency Degree

    OpenAIRE

    Yan Ge

    2014-01-01

    City intersection traffic signal control is an important method to improve the efficiency of road network and alleviate traffic congestion. This paper researches traffic signal fuzzy control method on a single intersection. A two-stage traffic signal control method based on traffic urgency degree is proposed according to two-stage fuzzy inference on single intersection. At the first stage, calculate traffic urgency degree for all red phases using traffic urgency evaluation module and select t...

  4. Integrated Variable Speed Limits Control and Ramp Metering for Bottleneck Regions on Freeway

    Directory of Open Access Journals (Sweden)

    Ming-hui Ma

    2015-01-01

    Full Text Available To enhance the efficiency of the existing freeway system and therefore to mitigate traffic congestion and related problems on the freeway mainline lane-drop bottleneck region, the advanced strategy for bottleneck control is essential. This paper proposes a method that integrates variable speed limits and ramp metering for freeway bottleneck region control to relieve the chaos in bottleneck region. To this end, based on the analyses of spatial-temporal patterns of traffic flow, a macroscopic traffic flow model is extended to describe the traffic flow operating characteristic by considering the impacts of variable speed limits in mainstream bottleneck region. In addition, to achieve the goal of balancing the priority of the vehicles on mainline and on-ramp, increasing capacity, and reducing travel delay on bottleneck region, an improved control model, as well as an advanced control strategy that integrates variable speed limits and ramp metering, is developed. The proposed method is tested in simulation for a real freeway infrastructure feed and calibrates real traffic variables. The results demonstrate that the proposed method can substantially improve the traffic flow efficiency of mainline and on-ramp and enhance the quality of traffic flow at the investigated freeway mainline bottleneck.

  5. Framework for Traffic Congestion Management

    Directory of Open Access Journals (Sweden)

    Mahmud Hassan TALUKDAR

    2013-06-01

    Full Text Available Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible to develop a framework which could be used with or without minor adjustment to deal with congestion problem. So, the main aim of this paper is to prepare a traffic congestion mitigation framework which will be useful for urban planners, transport planners, civil engineers, transport policy makers, congestion management researchers who are directly or indirectly involved or willing to involve in the task of traffic congestion management. Literature review is the main source of information of this study. In this paper, firstly, traffic congestion is defined on the theoretical point of view and then the causes of traffic congestion are briefly described. After describing the causes, common management measures, using world- wide, are described and framework for supply side and demand side congestion management measures are prepared.

  6. Traffic accidents on expressways: new threat to China.

    Science.gov (United States)

    Zhao, Jinbao; Deng, Wei

    2012-01-01

    As China is building one of the largest expressway systems in the world, expressway safety problems have become serious concerns to China. This article analyzed the trends in expressway accidents in China from 1995 to 2010 and examined the characteristics of these accidents. Expressway accident data were obtained from the Annual Report for Road Traffic Accidents published by the Ministry of Public Security of China. Expressway mileage data were obtained from the National Statistics Yearbook published by the National Bureau of Statistics of China. Descriptive statistical analyses were conducted based on these data. Expressway deaths increased by 10.2-fold from 616 persons in 1995 to 6300 persons in 2010, and the average annual increase was 17.9 percent over the past 15 years, and the overall other road traffic deaths was -0.33 percent. China's expressway mileage accounted for only 1.85 percent of highway mileage driven in 2010, but expressway deaths made up 13.54 percent of highway traffic deaths. The average annual accident lethality rate [accident deaths/(accident deaths + accident injuries)] for China's expressways was 27.76 percent during the period 1995 to 2010, which was 1.33 times higher than the accident lethality rate of highway traffic accidents. China's government should pay attention to expressway construction and safety interventions during the rapid development period of expressways. Related causes, such as geographic patterns, speeding, weather conditions, and traffic flow composition, need to be studied in the near future. An effective and scientific expressway safety management services system, composed of a speed monitoring system, warning system, and emergency rescue system, should be established in developed and underdeveloped provinces in China to improve safety on expressway.

  7. Modeling secondary accidents identified by traffic shock waves.

    Science.gov (United States)

    Junhua, Wang; Boya, Liu; Lanfang, Zhang; Ragland, David R

    2016-02-01

    The high potential for occurrence and the negative consequences of secondary accidents make them an issue of great concern affecting freeway safety. Using accident records from a three-year period together with California interstate freeway loop data, a dynamic method for more accurate classification based on the traffic shock wave detecting method was used to identify secondary accidents. Spatio-temporal gaps between the primary and secondary accident were proven be fit via a mixture of Weibull and normal distribution. A logistic regression model was developed to investigate major factors contributing to secondary accident occurrence. Traffic shock wave speed and volume at the occurrence of a primary accident were explicitly considered in the model, as a secondary accident is defined as an accident that occurs within the spatio-temporal impact scope of the primary accident. Results show that the shock waves originating in the wake of a primary accident have a more significant impact on the likelihood of a secondary accident occurrence than the effects of traffic volume. Primary accidents with long durations can significantly increase the possibility of secondary accidents. Unsafe speed and weather are other factors contributing to secondary crash occurrence. It is strongly suggested that when police or rescue personnel arrive at the scene of an accident, they should not suddenly block, decrease, or unblock the traffic flow, but instead endeavor to control traffic in a smooth and controlled manner. Also it is important to reduce accident processing time to reduce the risk of secondary accident. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Traffic instabilities in self-organized pedestrian crowds.

    Directory of Open Access Journals (Sweden)

    Mehdi Moussaïd

    Full Text Available 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.

  9. Changes in speed distribution: Applying aggregated safety effect models to individual vehicle speeds.

    Science.gov (United States)

    Vadeby, Anna; Forsman, Åsa

    2017-06-01

    This study investigated the effect of applying two aggregated models (the Power model and the Exponential model) to individual vehicle speeds instead of mean speeds. This is of particular interest when the measure introduced affects different parts of the speed distribution differently. The aim was to examine how the estimated overall risk was affected when assuming the models are valid on an individual vehicle level. Speed data from two applications of speed measurements were used in the study: an evaluation of movable speed cameras and a national evaluation of new speed limits in Sweden. The results showed that when applied on individual vehicle speed level compared with aggregated level, there was essentially no difference between these for the Power model in the case of injury accidents. However, for fatalities the difference was greater, especially for roads with new cameras where those driving fastest reduced their speed the most. For the case with new speed limits, the individual approach estimated a somewhat smaller effect, reflecting that changes in the 15th percentile (P15) were somewhat larger than changes in P85 in this case. For the Exponential model there was also a clear, although small, difference between applying the model to mean speed changes and individual vehicle speed changes when speed cameras were used. This applied both for injury accidents and fatalities. There were also larger effects for the Exponential model than for the Power model, especially for injury accidents. In conclusion, applying the Power or Exponential model to individual vehicle speeds is an alternative that provides reasonable results in relation to the original Power and Exponential models, but more research is needed to clarify the shape of the individual risk curve. It is not surprising that the impact on severe traffic crashes was larger in situations where those driving fastest reduced their speed the most. Further investigations on use of the Power and/or the

  10. OPTIMASI BANDWITH MENGGUNAKAN TRAFFIC SHAPPING

    Directory of Open Access Journals (Sweden)

    Imam Riadi

    2012-05-01

    Full Text Available Perkembangan layanan komunikasi telah berkembang sangat pesat. Salah satunya adalah pemanfaatan penggunaan bandwith untuk mengakases jaringan Internet. Traffic shapping bandwidth dapat memberikan efesiensi dalam hal pemanfaatan bandwidth pada instansi yang melakukan manajemen dalam lalulintas jaringannya. Metode yang digunakan dalam penelitian ini adalah metode literatur yaitu metode pengumpulan data yang dilakukan dengan mengumpulkan sumber-sumber data yang terkait dan metode eksperimen yaitu melakukan penelitian dengan mengkonfigurasi Mikrotik RouterOS untuk melakukan traffic shapping bandwidth. Hasil penelitian ini adalah router yang dapat melakukan traffic shapping sehingga kualitas koneksi menjadi lebih baik untuk mengakses dan mengambil data dari sebuah website.

  11. Traffic Light Detection at Night

    DEFF Research Database (Denmark)

    Jensen, Morten Bornø; Philipsen, Mark Philip; Bahnsen, Chris

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any in- telligent vehicle, it must function both at day and at night. However, the majority of TLR research is focused on day-time scenarios. In this paper we will focus on detection of traffic lights at night and evalu- ate the performance...... of three detectors based on heuristic models and one learning-based detector. Evaluation is done on night-time data from the public LISA Traffic Light Dataset. The learning-based detector out- performs the model-based detectors in both precision and recall. The learning-based detector achieves an average...

  12. Assessment of Traffic Noise Impacts

    DEFF Research Database (Denmark)

    Rich, Jeppe Husted; Nielsen, Otto Anker

    2004-01-01

    A steady growth in traffic intensities in most urban areas throughout the world has forced planners and politicians to seriously consider the resulting environmental impact, such as traffic noise, accidents and air pollution. The assessment of such negative factors is needed in order to reveal...... the true social benefit of infrastructure plans. The paper presents a noise assessment model for the Copenhagen region, which brings together GIS technology and non-linear hedonic regression models to reveal the implicit costs of traffic noise measured as the marginal percentage loss in property values...

  13. Speed in Acquisitions

    DEFF Research Database (Denmark)

    Meglio, Olimpia; King, David R.; Risberg, Annette

    2017-01-01

    The advantage of speed is often invoked by academics and practitioners as an essential condition during post-acquisition integration, frequently without consideration of the impact earlier decisions have on acquisition speed. In this article, we examine the role speed plays in acquisitions across...... the acquisition process using research organized around characteristics that display complexity with respect to acquisition speed. We incorporate existing research with a process perspective of acquisitions in order to present trade-offs, and consider the influence of both stakeholders and the pre......-deal-completion context on acquisition speed, as well as the organization’s capabilities to facilitating that speed. Observed trade-offs suggest both that acquisition speed often requires longer planning time before an acquisition and that associated decisions require managerial judgement. A framework for improving...

  14. Traffic Flow Condition Classification for Short Sections Using Single Microwave Sensor

    Directory of Open Access Journals (Sweden)

    Memiş Kemal

    2010-01-01

    Full Text Available Daily observed traffic flow can show different characteristics varying with the times of the day. They are caused by traffic incidents such as accidents, disabled cars, construction activities and other unusual events. Three different major traffic conditions can be occurred: "Flow," "Dense" and "Congested". Objective of this research is to identify the current traffic condition by examining the traffic measurement parameters. The earlier researches have dealt only with speed and volume by ignoring occupancy. In our study, the occupancy is another important parameter of classification. The previous works have used multiple sensors to classify traffic condition whereas our work uses only single microwave sensor. We have extended Multiple Linear Regression classification with our new approach of Estimating with Error Prediction. We present novel algorithms of Multiclassification with One-Against-All Method and Multiclassification with Binary Comparison for multiple SVM architecture. Finaly, a non-linear model of backpropagation neural network is introduced for classification. This combination has not been reported on previous studies. Training data are obtained from the Corsim based microscopic traffic simulator TSIS 5.1. All performances are compared using this data set. Our methods are currently installed and running at traffic management center of 2.Ring Road in Istanbul.

  15. Cellular automata model for urban road traffic flow considering pedestrian crossing street

    Science.gov (United States)

    Zhao, Han-Tao; Yang, Shuo; Chen, Xiao-Xu

    2016-11-01

    In order to analyze the effect of pedestrians' crossing street on vehicle flows, we investigated traffic characteristics of vehicles and pedestrians. Based on that, rules of lane changing, acceleration, deceleration, randomization and update are modified. Then we established two urban two-lane cellular automata models of traffic flow, one of which is about sections with non-signalized crosswalk and the other is on uncontrolled sections with pedestrians crossing street at random. MATLAB is used for numerical simulation of the different traffic conditions; meanwhile space-time diagram and relational graphs of traffic flow parameters are generated and then comparatively analyzed. Simulation results indicate that when vehicle density is lower than around 25 vehs/(km lane), pedestrians have modest impact on traffic flow, whereas when vehicle density is higher than about 60 vehs/(km lane), traffic speed and volume will decrease significantly especially on sections with non-signal-controlled crosswalk. The results illustrate that the proposed models reconstruct the traffic flow's characteristic with the situation where there are pedestrians crossing and can provide some practical reference for urban traffic management.

  16. Comparison of classical statistical methods and artificial neural network in traffic noise prediction

    International Nuclear Information System (INIS)

    Nedic, Vladimir; Despotovic, Danijela; Cvetanovic, Slobodan; Despotovic, Milan; Babic, Sasa

    2014-01-01

    Traffic is the main source of noise in urban environments and significantly affects human mental and physical health and labor productivity. Therefore it is very important to model the noise produced by various vehicles. Techniques for traffic noise prediction are mainly based on regression analysis, which generally is not good enough to describe the trends of noise. In this paper the application of artificial neural networks (ANNs) for the prediction of traffic noise is presented. As input variables of the neural network, the proposed structure of the traffic flow and the average speed of the traffic flow are chosen. The output variable of the network is the equivalent noise level in the given time period L eq . Based on these parameters, the network is modeled, trained and tested through a comparative analysis of the calculated values and measured levels of traffic noise using the originally developed user friendly software package. It is shown that the artificial neural networks can be a useful tool for the prediction of noise with sufficient accuracy. In addition, the measured values were also used to calculate equivalent noise level by means of classical methods, and comparative analysis is given. The results clearly show that ANN approach is superior in traffic noise level prediction to any other statistical method. - Highlights: • We proposed an ANN model for prediction of traffic noise. • We developed originally designed user friendly software package. • The results are compared with classical statistical methods. • The results are much better predictive capabilities of ANN model

  17. Crash risk analysis during fog conditions using real-time traffic data.

    Science.gov (United States)

    Wu, Yina; Abdel-Aty, Mohamed; Lee, Jaeyoung

    2018-05-01

    This research investigates the changes of traffic characteristics and crash risks during fog conditions. Using real-time traffic flow and weather data at two regions in Florida, the traffic patterns at the fog duration were compared to the traffic patterns at the clear duration. It was found that the average 5-min speed and the average 5-min volume were prone to decreasing during fog. Based on previous studies, a "Crash Risk Increase Indicator (CRII)" was proposed to explore the differences of crash risk between fog and clear conditions. A binary logistic regression model was applied to link the increase of crash risks with traffic flow characteristics. The results suggested that the proposed indicator worked well in evaluating the increase of crash risk under fog condition. It was indicated that the crash risk was prone to increase at ramp vicinities in fog conditions. Also, the average 5-min volume during fog and the lane position are important factors for crash risk increase. The differences between the regions were also explored in this study. The results indicated that the locations with heavier traffic or locations at the lanes that were closest to the median in Region 2 were more likely to observe an increase in crash risks in fog conditions. It is expected that the proposed indicator can help identify the dangerous traffic status under fog conditions and then proper ITS technologies can be implemented to enhance traffic safety when the visibility declines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Comparison of classical statistical methods and artificial neural network in traffic noise prediction

    Energy Technology Data Exchange (ETDEWEB)

    Nedic, Vladimir, E-mail: vnedic@kg.ac.rs [Faculty of Philology and Arts, University of Kragujevac, Jovana Cvijića bb, 34000 Kragujevac (Serbia); Despotovic, Danijela, E-mail: ddespotovic@kg.ac.rs [Faculty of Economics, University of Kragujevac, Djure Pucara Starog 3, 34000 Kragujevac (Serbia); Cvetanovic, Slobodan, E-mail: slobodan.cvetanovic@eknfak.ni.ac.rs [Faculty of Economics, University of Niš, Trg kralja Aleksandra Ujedinitelja, 18000 Niš (Serbia); Despotovic, Milan, E-mail: mdespotovic@kg.ac.rs [Faculty of Engineering, University of Kragujevac, Sestre Janjic 6, 34000 Kragujevac (Serbia); Babic, Sasa, E-mail: babicsf@yahoo.com [College of Applied Mechanical Engineering, Trstenik (Serbia)

    2014-11-15

    Traffic is the main source of noise in urban environments and significantly affects human mental and physical health and labor productivity. Therefore it is very important to model the noise produced by various vehicles. Techniques for traffic noise prediction are mainly based on regression analysis, which generally is not good enough to describe the trends of noise. In this paper the application of artificial neural networks (ANNs) for the prediction of traffic noise is presented. As input variables of the neural network, the proposed structure of the traffic flow and the average speed of the traffic flow are chosen. The output variable of the network is the equivalent noise level in the given time period L{sub eq}. Based on these parameters, the network is modeled, trained and tested through a comparative analysis of the calculated values and measured levels of traffic noise using the originally developed user friendly software package. It is shown that the artificial neural networks can be a useful tool for the prediction of noise with sufficient accuracy. In addition, the measured values were also used to calculate equivalent noise level by means of classical methods, and comparative analysis is given. The results clearly show that ANN approach is superior in traffic noise level prediction to any other statistical method. - Highlights: • We proposed an ANN model for prediction of traffic noise. • We developed originally designed user friendly software package. • The results are compared with classical statistical methods. • The results are much better predictive capabilities of ANN model.

  19. A High Speed Mobile Communication System implementing Bicasting Architecture on the IP Layer

    OpenAIRE

    Yamada, Kazuhiro

    2012-01-01

    Having a broadband connection on high speed rails is something that business travelers want most. Increasing number of passengers is requesting even higher access speeds. We are proposing the Media Convergence System as an ideal communication system for future high speed mobile entities. The Media Convergence System recognizes plural wireless communication media between the ground network and each train, and then traffic is load-balanced over active media which varies according to circumstanc...

  20. [Comics for traffic education: evaluation of a traffic safety campaign].

    Science.gov (United States)

    Bonfadelli, H

    1989-01-01

    Traffic safety campaigns often are ineffective to change driving behavior because they don't reach the target group or are recognized only by people who are already interested or concerned. The evaluation of a traffic safety campaign called "Leo Lässig", addressed to young new drivers, shows that recognition and acceptance by the target group were stimulated by the age-conform means of comic-strips.

  1. An epidemiological survey on road traffic crashes in Iran: application of the two logistic regression models.

    Science.gov (United States)

    Bakhtiyari, Mahmood; Mehmandar, Mohammad Reza; Mirbagheri, Babak; Hariri, Gholam Reza; Delpisheh, Ali; Soori, Hamid

    2014-01-01

    Risk factors of human-related traffic crashes are the most important and preventable challenges for community health due to their noteworthy burden in developing countries in particular. The present study aims to investigate the role of human risk factors of road traffic crashes in Iran. Through a cross-sectional study using the COM 114 data collection forms, the police records of almost 600,000 crashes occurred in 2010 are investigated. The binary logistic regression and proportional odds regression models are used. The odds ratio for each risk factor is calculated. These models are adjusted for known confounding factors including age, sex and driving time. The traffic crash reports of 537,688 men (90.8%) and 54,480 women (9.2%) are analysed. The mean age is 34.1 ± 14 years. Not maintaining eyes on the road (53.7%) and losing control of the vehicle (21.4%) are the main causes of drivers' deaths in traffic crashes within cities. Not maintaining eyes on the road is also the most frequent human risk factor for road traffic crashes out of cities. Sudden lane excursion (OR = 9.9, 95% CI: 8.2-11.9) and seat belt non-compliance (OR = 8.7, CI: 6.7-10.1), exceeding authorised speed (OR = 17.9, CI: 12.7-25.1) and exceeding safe speed (OR = 9.7, CI: 7.2-13.2) are the most significant human risk factors for traffic crashes in Iran. The high mortality rate of 39 people for every 100,000 population emphasises on the importance of traffic crashes in Iran. Considering the important role of human risk factors in traffic crashes, struggling efforts are required to control dangerous driving behaviours such as exceeding speed, illegal overtaking and not maintaining eyes on the road.

  2. Traffic signal phasing at intersections to improve safety for alcohol-affected pedestrians.

    Science.gov (United States)

    Lenné, Michael G; Corben, Bruce F; Stephan, Karen

    2007-07-01

    Alcohol-affected pedestrians are among the highest-risk groups involved in pedestrian casualty crashes. This paper investigates the opportunities to use a modified form of traffic signal operation during high-risk periods and at high-risk locations to reduce alcohol-affected pedestrian crashes and the severity of injuries that might otherwise occur. The 'Dwell-on-Red' treatment involves displaying a red traffic signal to all vehicle directions during periods when no vehicular traffic is detected, so that drivers approach high-risk intersections at a lower speed than if a green signal were displayed. Vehicle speed data were collected before and after treatment activation at both a control and treatment site. Speed data were collected both 30 m prior to and at the intersection stop line. The treatment was associated with a reduction in mean vehicle speeds of 3.9 kph (9%) and 11.0 kph (28%) at 30 m and stop line collection points, respectively, and substantial reductions in the proportion of vehicles travelling at threatening speeds with regard to the severity of pedestrian injury. Other important road safety concerns may also benefit from this form of traffic signal modification, and it is recommended that other areas of application be explored, including the other severe trauma categories typically concentrated around signalised intersections.

  3. Effects of low speed wind on the recognition/identification and pass-through communication tasks of auditory situation awareness afforded by military hearing protection/enhancement devices and tactical communication and protective systems.

    Science.gov (United States)

    Lee, Kichol; Casali, John G

    2016-01-01

    To investigate the effect of controlled low-speed wind-noise on the auditory situation awareness performance afforded by military hearing protection/enhancement devices (HPED) and tactical communication and protective systems (TCAPS). Recognition/identification and pass-through communications tasks were separately conducted under three wind conditions (0, 5, and 10 mph). Subjects wore two in-ear-type TCAPS, one earmuff-type TCAPS, a Combat Arms Earplug in its 'open' or pass-through setting, and an EB-15LE electronic earplug. Devices with electronic gain systems were tested under two gain settings: 'unity' and 'max'. Testing without any device (open ear) was conducted as a control. Ten subjects were recruited from the student population at Virginia Tech. Audiometric requirements were 25 dBHL or better at 500, 1000, 2000, 4000, and 8000 Hz in both ears. Performance on the interaction of communication task-by-device was significantly different only in 0 mph wind speed. The between-device performance differences varied with azimuthal speaker locations. It is evident from this study that stable (non-gusting) wind speeds up to 10 mph did not significantly degrade recognition/identification task performance and pass-through communication performance of the group of HPEDs and TCAPS tested. However, the various devices performed differently as the test sound signal speaker location was varied and it appears that physical as well as electronic features may have contributed to this directional result.

  4. Lagrangian Multi-Class Traffic State Estimation

    NARCIS (Netherlands)

    Yuan, Y.

    2013-01-01

    Road traffic is important to everybody in the world. People travel and commute everyday. For those who travel by cars (or other types of road vehicles), traffic congestion is a daily experience. One essential goal of traffic researchers is to reduce traffic congestion and to improve the whole

  5. Impact of distracted driving on safety and traffic flow.

    Science.gov (United States)

    Stavrinos, Despina; Jones, Jennifer L; Garner, Annie A; Griffin, Russell; Franklin, Crystal A; Ball, David; Welburn, Sharon C; Ball, Karlene K; Sisiopiku, Virginia P; Fine, Philip R

    2013-12-01

    Studies have documented a link between distracted driving and diminished safety; however, an association between distracted driving and traffic congestion has not been investigated in depth. The present study examined the behavior of teens and young adults operating a driving simulator while engaged in various distractions (i.e., cell phone, texting, and undistracted) and driving conditions (i.e., free flow, stable flow, and oversaturation). Seventy five participants 16-25 years of age (split into 2 groups: novice drivers and young adults) drove a STISIM simulator three times, each time with one of three randomly presented distractions. Each drive was designed to represent daytime scenery on a 4 lane divided roadway and included three equal roadway portions representing Levels of Service (LOS) A, C, and E as defined in the 2000 Highway Capacity Manual. Participants also completed questionnaires documenting demographics and driving history. Both safety and traffic flow related driving outcomes were considered. A Repeated Measures Multivariate Analysis of Variance was employed to analyze continuous outcome variables and a Generalized Estimate Equation (GEE) Poisson model was used to analyze count variables. Results revealed that, in general more lane deviations and crashes occurred during texting. Distraction (in most cases, text messaging) had a significantly negative impact on traffic flow, such that participants exhibited greater fluctuation in speed, changed lanes significantly fewer times, and took longer to complete the scenario. In turn, more simulated vehicles passed the participant drivers while they were texting or talking on a cell phone than while undistracted. The results indicate that distracted driving, particularly texting, may lead to reduced safety and traffic flow, thus having a negative impact on traffic operations. No significant differences were detected between age groups, suggesting that all drivers, regardless of age, may drive in a manner

  6. PERFORMANCE ANALYSIS OF IPv4 AND IPv6 INTERNET TRAFFIC

    Directory of Open Access Journals (Sweden)

    Rupesh Jaiswal

    2015-12-01

    Full Text Available The gigantic growth of the internet communication technology has illustrated its value and benefits to private businesses, government organizations, worldwide professionals, academic institutes and individuals over the past few years. The size and range of computing devices connected to the internet, substantially increased because of IPv6 and offers the potential to establish a much more powerful internet compared to the IPv4. IPV6 developed by the IETF to deal with a shortage of IP addresses under IPv4. New features of IPv6 enhance packet processing speeds over routers, switches and end systems. These improved features will have different traffic characteristics than IPv4. The internet traffic which was earlier assumed as Poisson is now shown to have fractal characteristics as; heavy tailedness, self-similarity and long range dependency. Internet traffic showing above characteristics are found to have burstiness at multiple timescales. This behavior impacts network performance and degrades it substantially. It also increases complexity for network design and create difficulties to maintain desired QoS. IPv4 traffic has been well established as self-similar traffic. Nowadays, IPv6 forming a larger share of the internet traffic and it is pivotal to asses IPv6 with regards to fractal behavior. This will enable network designers to do necessary changes in the existing network to reconcile with IPv6. In this paper we compared IPv4 and IPv6 with respect to fractal behavioral characteristics. It is found that IPv6 shows higher degree of heavy tailedness, higher values of Hurst parameter values, higher fractal dimension values i.e. it is more self-similar, greater autocorrelation achieved even at larger lag and thus showing more burstiness.

  7. An extended heterogeneous car-following model accounting for anticipation driving behavior and mixed maximum speeds

    Science.gov (United States)

    Sun, Fengxin; Wang, Jufeng; Cheng, Rongjun; Ge, Hongxia

    2018-02-01

    The optimal driving speeds of the different vehicles may be different for the same headway. In the optimal velocity function of the optimal velocity (OV) model, the maximum speed vmax is an important parameter determining the optimal driving speed. A vehicle with higher maximum speed is more willing to drive faster than that with lower maximum speed in similar situation. By incorporating the anticipation driving behavior of relative velocity and mixed maximum speeds of different percentages into optimal velocity function, an extended heterogeneous car-following model is presented in this paper. The analytical linear stable condition for this extended heterogeneous traffic model is obtained by using linear stability theory. Numerical simulations are carried out to explore the complex phenomenon resulted from the cooperation between anticipation driving behavior and heterogeneous maximum speeds in the optimal velocity function. The analytical and numerical results all demonstrate that strengthening driver's anticipation effect can improve the stability of heterogeneous traffic flow, and increasing the lowest value in the mixed maximum speeds will result in more instability, but increasing the value or proportion of the part already having higher maximum speed will cause different stabilities at high or low traffic densities.

  8. Traffic behavior at freeway bottlenecks.

    Science.gov (United States)

    2014-09-01

    This study examines traffic behavior in the vicinity of a freeway bottleneck, revisiting commonly held : assumptions and uncovering systematic biases that likely have distorted empirical studies of bottleneck : formation, capacity drop, and the funda...

  9. Traffic fatalities and economic growth

    Science.gov (United States)

    2003-04-01

    As countries develop death rates usually fall, especially for diseases that affect the young and result in substantial life-years lost. Deaths due to traffic accidents are a notable exception: the growth in motor vehicles that accompanies economic gr...

  10. Automatic Traffic Recorder (ATR) Stations

    Data.gov (United States)

    Department of Homeland Security — The data included in the GIS Traffic Stations Version database have been assimilated from station description files provided by FHWA for Weigh-in-Motion (WIM), and...

  11. AAA Foundation for Traffic Safety

    Science.gov (United States)

    ... of Top Deadly Mistakes Made by Teen Drivers -- AAA AAA: Road debris causes avoidable crashes, deaths Save the ... and 500 deaths! Foundation News Stay Tuned New AAA Foundation for Traffic Safety website coming Fall 2017 ...

  12. Game theory and traffic assignment.

    Science.gov (United States)

    2013-09-01

    Traffic assignment is used to determine the number of users on roadway links in a network. While this problem has : been widely studied in transportation literature, its use of the concept of equilibrium has attracted considerable interest : in the f...

  13. Estimating Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Jørgensen, Morten W.; Sorenson, Spencer C.

    1998-01-01

    Several parameters of importance for estimating emissions from railway traffic are discussed, and typical results presented. Typical emissions factors from diesel engines and electrical power generation are presented, and the effect of differences in national electrical generation sources...

  14. Multi-Speed Transmission For Commercial Delivery Medium Duty PEDVs

    Energy Technology Data Exchange (ETDEWEB)

    Chavdar, Bulent [Eaton Corp., Menomonee Falls, WI (United States)

    2017-12-31

    of the prototype units was fully integrated into a Proterra BE35 demonstration electric bus. The shift control strategy was fine-tuned on the integrated vehicle at Eaton Marshall Proving Grounds. NREL tested the vehicle and validated the performance gains. Simulations predicted up to 20% increase in system energy efficiency depending on drive cycles, a top speed of greater than70 mph on flat road, 40% faster acceleration and a doubled gradeability with four-speed transmission as compared to the baseline EVs. Chassis Dyno Tests at NREL verified the simulation results of Eaton team and the HIL test results of ORNL team. The new four-speed EV transmission is efficient, reliable, modular, scalable, light weight, small size, and will be affordable. Furthermore, four-speed transmission enables downsizing of motor, battery and final drive, thereby reducing the total system cost.

  15. Reports on internet traffic statistics

    OpenAIRE

    Hoogesteger, Martijn; de Oliveira Schmidt, R.; Sperotto, Anna; Pras, Aiko

    2013-01-01

    Internet traffic statistics can provide valuable information to network analysts and researchers about the way nowadays networks are used. In the past, such information was provided by Internet2 in a public website called Internet2 NetFlow: Weekly Reports. The website reported traffic statistics from the Abilene network on a weekly basis. At that time, the network connected 230 research institutes with a 10Gb/s link. Although these reports were limited to the behavior of the Albeline's users,...

  16. Regulatory measures for traffic safety

    International Nuclear Information System (INIS)

    Veerapur, R.D.; Bharambe, S.D.; Patnaik, S.K.; Tandle, A.K.; Sonawane, K.A.; Kumar, Rajesh; Venkat Subramanian, K.

    2017-01-01

    Traffic safety is an issue related to occupational safety not restricted alone to the transportation but extends beyond. BARC has many facilities spread across large area in Mumbai and outside Mumbai. BARC deploys large number of buses, mini buses, jeeps and cars for commuting its employees to reach BARC and for commuting within BARC premises. Additionally, trucks, fire tenders, trailers etc. are also deployed for transportation of materials. No moving vehicle is ever free of the possibility of involvement in an accident. Vehicular accidents and the fatalities on road are the result of inter-play of a number of factors. The vehicle population has been steadily increasing with the pace picking up significantly in recent past. Increase in vehicle population in the face of limited road space used by a large variety of traffic has heightened the need and urgency for a well-thought-out road safety. Therefore, existence of regulatory authority to regulate traffic and vehicles to ensure safety of its employees and vehicles is very essential. BARC Traffic Safety Committee (BTSC), which is the regulating body for traffic safety is responsible for ensuring overall traffic safety. (author)

  17. Classification of Automated Search Traffic

    Science.gov (United States)

    Buehrer, Greg; Stokes, Jack W.; Chellapilla, Kumar; Platt, John C.

    As web search providers seek to improve both relevance and response times, they are challenged by the ever-increasing tax of automated search query traffic. Third party systems interact with search engines for a variety of reasons, such as monitoring a web site’s rank, augmenting online games, or possibly to maliciously alter click-through rates. In this paper, we investigate automated traffic (sometimes referred to as bot traffic) in the query stream of a large search engine provider. We define automated traffic as any search query not generated by a human in real time. We first provide examples of different categories of query logs generated by automated means. We then develop many different features that distinguish between queries generated by people searching for information, and those generated by automated processes. We categorize these features into two classes, either an interpretation of the physical model of human interactions, or as behavioral patterns of automated interactions. Using the these detection features, we next classify the query stream using multiple binary classifiers. In addition, a multiclass classifier is then developed to identify subclasses of both normal and automated traffic. An active learning algorithm is used to suggest which user sessions to label to improve the accuracy of the multiclass classifier, while also seeking to discover new classes of automated traffic. Performance analysis are then provided. Finally, the multiclass classifier is used to predict the subclass distribution for the search query stream.

  18. Flood and Traffic Wireless Monitoring System for Smart Cities

    KAUST Repository

    Moussa, Mustafa

    2016-10-01

    The convergence of computation, communication and sensing has led to the emergence of Wireless Sensor Networks (WSNs), which allow distributed monitoring of physical phenomena over extended areas. In this thesis, we focus on a dual flood and traffic flow WSN applicable to urban environments. This fixed sensing system is based on the combination of ultrasonic range-finding with remote temperature sensing, and can sense both phenomena with a high degree of accuracy. This enables the monitoring of urban areas to lessen the impact of catastrophic flood events, by monitoring flood parameters and traffic flow to enable public evacuation and early warning, allocate the resources efficiently or control the traffic to make cities more productive and smarter. We present an implementation of the device, and illustrate its performance in water level estimation and rain detection using a novel combination of L1 regularized reconstruction and machine learning algorithms on a 6-month dataset involving four different sensors. Our results show that water level can be estimated with an uncertainty of 1 cm using a combination of thermal sensing and ultrasonic distance measurements. The demonstration of the performance included the detection of an actual flash flood event using two sensors located in Umm Al Qura University (Mecca). Finally, we show that Lagrangian (mobile) sensors can be used to inexpensively increase the performance of the system with respect to traffic sensing. These sensors are based on Inertial Measurement Units (IMUs), which have never been investigated in the context of traffic ow monitoring before. We investigate the divergence of the speed estimation process, the lack of the calibration parameters of the system, and the problem of reconstructing vehicle trajectories evolving in a given transportation network. To address these problems, we propose an automatic calibration algorithm applicable to IMU-equipped ground vehicles, and an L1 regularized least squares

  19. Speed and income

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2005-01-01

    The relationship between speed and income is established in a microeconomic model focusing on the trade-off between travel time and the risk of receiving a penalty for exceeding the speed limit. This is used to determine when a rational driver will choose to exceed the speed limit. The relationship...... between speed and income is found again in the empirical analysis of a cross-sectional dataset comprising 60,000 observations of car trips. This is used to perform regressions of speed on income, distance travelled, and a number of controls. The results are clearly statistically significant and indicate...... an average income elasticity of speed of 0.02; it is smaller at short distances and about twice as large at the longest distance investigated of 200 km....

  20. Automated Mixed Traffic Vehicle (AMTV) technology and safety study

    Science.gov (United States)

    Johnston, A. R.; Peng, T. K. C.; Vivian, H. C.; Wang, P. K.

    1978-01-01

    Technology and safety related to the implementation of an Automated Mixed Traffic Vehicle (AMTV) system are discussed. System concepts and technology status were reviewed and areas where further development is needed are identified. Failure and hazard modes were also analyzed and methods for prevention were suggested. The results presented are intended as a guide for further efforts in AMTV system design and technology development for both near term and long term applications. The AMTV systems discussed include a low speed system, and a hybrid system consisting of low speed sections and high speed sections operating in a semi-guideway. The safety analysis identified hazards that may arise in a properly functioning AMTV system, as well as hardware failure modes. Safety related failure modes were emphasized. A risk assessment was performed in order to create a priority order and significant hazards and failure modes were summarized. Corrective measures were proposed for each hazard.

  1. Using multisensory cues to facilitate air traffic management.

    Science.gov (United States)

    Ngo, Mary K; Pierce, Russell S; Spence, Charles

    2012-12-01

    In the present study, we sought to investigate whether auditory and tactile cuing could be used to facilitate a complex, real-world air traffic management scenario. Auditory and tactile cuing provides an effective means of improving both the speed and accuracy of participants' performance in a variety of laboratory-based visual target detection and identification tasks. A low-fidelity air traffic simulation task was used in which participants monitored and controlled aircraft.The participants had to ensure that the aircraft landed or exited at the correct altitude, speed, and direction and that they maintained a safe separation from all other aircraft and boundaries. The performance measures recorded included en route time, handoff delay, and conflict resolution delay (the performance measure of interest). In a baseline condition, the aircraft in conflict was highlighted in red (visual cue), and in the experimental conditions, this standard visual cue was accompanied by a simultaneously presented auditory, vibrotactile, or audiotactile cue. Participants responded significantly more rapidly, but no less accurately, to conflicts when presented with an additional auditory or audiotactile cue than with either a vibrotactile or visual cue alone. Auditory and audiotactile cues have the potential for improving operator performance by reducing the time it takes to detect and respond to potential visual target events. These results have important implications for the design and use of multisensory cues in air traffic management.

  2. Stereo-based Collision Avoidance System for Urban Traffic

    Science.gov (United States)

    Moriya, Takashi; Ishikawa, Naoto; Sasaki, Kazuyuki; Nakajima, Masato

    2002-11-01

    Numerous car accidents occur on urban road. However, researches done so far on driving assistance are subjecting highways whose environment is relatively simple and easy to handle, and new approach for urban settings is required. Our purpose is to extend its support to the following conditions in city traffic: the presence of obstacles such as pedestrians and telephone poles; the lane mark is not always drawn on a road; drivers may lack the sense of awareness of the lane mark. We propose a collision avoidance system, which can be applied to both highways and urban traffic environment. In our system, stereo cameras are set in front of a vehicle and the captured images are processed through a computer. We create a Projected Disparity Map (PDM) from stereo image pair, which is a disparity histogram taken along ordinate direction of obtained disparity image. When there is an obstacle in front, we can detect it by finding a peak appeared in the PDM. With a speed meter and a steering sensor, the stop distance and the radius of curvature of the self-vehicle are calculated, in order to set the observation-required area, which does not depend on lane marks, within a PDM. A danger level will be computed from the distance and the relative speed to the closest approaching object detected within the observation-required area. The method has been tested in urban traffic scenes and has shown to be effective for judging dangerous situation, and gives proper alarm to a driver.

  3. Experimental high-speed network

    Science.gov (United States)

    McNeill, Kevin M.; Klein, William P.; Vercillo, Richard; Alsafadi, Yasser H.; Parra, Miguel V.; Dallas, William J.

    1993-09-01

    Many existing local area networking protocols currently applied in medical imaging were originally designed for relatively low-speed, low-volume networking. These protocols utilize small packet sizes appropriate for text based communication. Local area networks of this type typically provide raw bandwidth under 125 MHz. These older network technologies are not optimized for the low delay, high data traffic environment of a totally digital radiology department. Some current implementations use point-to-point links when greater bandwidth is required. However, the use of point-to-point communications for a total digital radiology department network presents many disadvantages. This paper describes work on an experimental multi-access local area network called XFT. The work includes the protocol specification, and the design and implementation of network interface hardware and software. The protocol specifies the Physical and Data Link layers (OSI layers 1 & 2) for a fiber-optic based token ring providing a raw bandwidth of 500 MHz. The protocol design and implementation of the XFT interface hardware includes many features to optimize image transfer and provide flexibility for additional future enhancements which include: a modular hardware design supporting easy portability to a variety of host system buses, a versatile message buffer design providing 16 MB of memory, and the capability to extend the raw bandwidth of the network to 3.0 GHz.

  4. Cellular automata model for traffic flow with safe driving conditions

    International Nuclear Information System (INIS)

    Lárraga María Elena; Alvarez-Icaza Luis

    2014-01-01

    In this paper, a recently introduced cellular automata (CA) model is used for a statistical analysis of the inner microscopic structure of synchronized traffic flow. The analysis focuses on the formation and dissolution of clusters or platoons of vehicles, as the mechanism that causes the presence of this synchronized traffic state with a high flow. This platoon formation is one of the most interesting phenomena observed in traffic flows and plays an important role both in manual and automated highway systems (AHS). Simulation results, obtained from a single-lane system under periodic boundary conditions indicate that in the density region where the synchronized state is observed, most vehicles travel together in platoons with approximately the same speed and small spatial distances. The examination of velocity variations and individual vehicle gaps shows that the flow corresponding to the synchronized state is stable, safe and highly correlated. Moreover, results indicate that the observed platoon formation in real traffic is reproduced in simulations by the relation between vehicle headway and velocity that is embedded in the dynamics definition of the CA model. (general)

  5. Highway traffic simulation on multi-processor computers

    Energy Technology Data Exchange (ETDEWEB)

    Hanebutte, U.R.; Doss, E.; Tentner, A.M.

    1997-04-01

    A computer model has been developed to simulate highway traffic for various degrees of automation with a high level of fidelity in regard to driver control and vehicle characteristics. The model simulates vehicle maneuvering in a multi-lane highway traffic system and allows for the use of Intelligent Transportation System (ITS) technologies such as an Automated Intelligent Cruise Control (AICC). The structure of the computer model facilitates the use of parallel computers for the highway traffic simulation, since domain decomposition techniques can be applied in a straight forward fashion. In this model, the highway system (i.e. a network of road links) is divided into multiple regions; each region is controlled by a separate link manager residing on an individual processor. A graphical user interface augments the computer model kv allowing for real-time interactive simulation control and interaction with each individual vehicle and road side infrastructure element on each link. Average speed and traffic volume data is collected at user-specified loop detector locations. Further, as a measure of safety the so- called Time To Collision (TTC) parameter is being recorded.

  6. Modeling connected and autonomous vehicles in heterogeneous traffic flow

    Science.gov (United States)

    Ye, Lanhang; Yamamoto, Toshiyuki

    2018-01-01

    The objective of this study was to develop a heterogeneous traffic-flow model to study the possible impact of connected and autonomous vehicles (CAVs) on the traffic flow. Based on a recently proposed two-state safe-speed model (TSM), a two-lane cellular automaton (CA) model was developed, wherein both the CAVs and conventional vehicles were incorporated in the heterogeneous traffic flow. In particular, operation rules for CAVs are established considering the new characteristics of this emerging technology, including autonomous driving through the adaptive cruise control and inter-vehicle connection via short-range communication. Simulations were conducted under various CAV-penetration rates in the heterogeneous flow. The impact of CAVs on the road capacity was numerically investigated. The simulation results indicate that the road capacity increases with an increase in the CAV-penetration rate within the heterogeneous flow. Up to a CAV-penetration rate of 30%, the road capacity increases gradually; the effect of the difference in the CAV capability on the growth rate is insignificant. When the CAV-penetration rate exceeds 30%, the growth rate is largely decided by the capability of the CAV. The greater the capability, the higher the road-capacity growth rate. The relationship between the CAV-penetration rate and the road capacity is numerically analyzed, providing some insights into the possible impact of the CAVs on traffic systems.

  7. High speed atom source

    International Nuclear Information System (INIS)

    Hoshino, Hitoshi.

    1990-01-01

    In a high speed atom source, since the speed is not identical between ions and electrons, no sufficient neutralizing effect for ionic rays due to the mixing of the ionic rays and the electron rays can be obtained failing to obtain high speed atomic rays at high density. In view of the above, a speed control means is disposed for equalizing the speed of ions forming ionic rays and the speed of electrons forming electron rays. Further, incident angle of the electron rays and/or ionic rays to a magnet or an electrode is made variable. As a result, the relative speed between the ions and the electrons to the processing direction is reduced to zero, in which the probability of association between the ions and the electrons due to the coulomb force is increased to improve the neutralizing efficiency to easily obtain fine and high density high speed electron rays. Further, by varying the incident angle, a track capable of obtaining an ideal mixing depending on the energy of the neutralized ionic rays is formed. Since the high speed electron rays has such high density, they can be irradiated easily to the minute region of the specimen. (N.H.)

  8. Computer ray tracing speeds.

    Science.gov (United States)

    Robb, P; Pawlowski, B

    1990-05-01

    The results of measuring the ray trace speed and compilation speed of thirty-nine computers in fifty-seven configurations, ranging from personal computers to super computers, are described. A correlation of ray trace speed has been made with the LINPACK benchmark which allows the ray trace speed to be estimated using LINPACK performance data. The results indicate that the latest generation of workstations, using CPUs based on RISC (Reduced Instruction Set Computer) technology, are as fast or faster than mainframe computers in compute-bound situations.

  9. enviroCar - citizen science for sustainable traffic

    Science.gov (United States)

    Stasch, Christoph; Remke, Albert; Jirka, Simon; Nuest, Daniel

    2015-04-01

    Optimizing traffic flow is a challenging task, affecting both the mobility of people and the environment. Up to now, traffic monitoring is based on small samples using GPS devices or remote sensors such as cameras. Citizens are usually not actively involved in the process of collecting or analyzing traffic data. The enviroCar project (www.envirocar.org) aims at addressing this situation by providing an open platform that can be used by everyone to collect and analyze traffic-related data and thus to achieve sustainable traffic management by answering questions such as: How is the average speed on a certain route? Where are exceptionally long waiting times in front of traffic lights? At which crossings do more cars stop than drive through? Where are hotspots of fuel consumption and air pollutant emission during a certain time interval? In this presentation, an overview on the enviroCar project is given and current research challenges addressed in the context of the project are presented. Citizens are able to participate by registering at the enviroCar portal and downloading the enviroCar Android app. Once installed, the Android app allows citizens to collect car sensor data, e.g. speed, mass air flow, or intake temperature via an On-Board Diagnosis 2 (OBD-II) Adapter. After finishing a car ride, the data can be uploaded to the central enviroCar server where the data is anonymized and published as open data. Each enviroCar member has a profile page giving control on his own data and providing statistics on personal driving behavior. The portal also allows comparing personal statistics with the statistics of other members. It thus facilitates analysis whether, for example, a member is driving in a more fuel saving manner than other users. Besides only acting as a data collector, citizens can also explore the enviroCar data in online maps or download the data in standard formats for certain spatial areas and/or time intervals allowing them to conduct spatio

  10. Hazardous Traffic Event Detection Using Markov Blanket and Sequential Minimal Optimization (MB-SMO

    Directory of Open Access Journals (Sweden)

    Lixin Yan

    2016-07-01

    Full Text Available The ability to identify hazardous traffic events is already considered as one of the most effective solutions for reducing the occurrence of crashes. Only certain particular hazardous traffic events have been studied in previous studies, which were mainly based on dedicated video stream data and GPS data. The objective of this study is twofold: (1 the Markov blanket (MB algorithm is employed to extract the main factors associated with hazardous traffic events; (2 a model is developed to identify hazardous traffic event using driving characteristics, vehicle trajectory, and vehicle position data. Twenty-two licensed drivers were recruited to carry out a natural driving experiment in Wuhan, China, and multi-sensor information data were collected for different types of traffic events. The results indicated that a vehicle’s speed, the standard deviation of speed, the standard deviation of skin conductance, the standard deviation of brake pressure, turn signal, the acceleration of steering, the standard deviation of acceleration, and the acceleration in Z (G have significant influences on hazardous traffic events. The sequential minimal optimization (SMO algorithm was adopted to build the identification model, and the accuracy of prediction was higher than 86%. Moreover, compared with other detection algorithms, the MB-SMO algorithm was ranked best in terms of the prediction accuracy. The conclusions can provide reference evidence for the development of dangerous situation warning products and the design of intelligent vehicles.

  11. Appreciation of the traffic effects on the RST by infrared thermography

    Science.gov (United States)

    Khalifa, Abderrahmen; Marchetti, Mario; Buès, Michel

    2014-09-01

    Road surface temperature forecast is a key component of winter maintenance strategy in many developed countries. Numerical tools exist to help road managers to organize services and consequently to trigger de-icing operations. Forecasting strategies have been commonplace since the 1980s, and often based on numerical models. Traffic is one of the influencing parameters, specifically in urban areas. This work was undertaken to evaluate to which extent an accurate description of traffic might improve numerical model dedicated to road surface temperature forecasting. Two sets of experiments were run to detect and to quantify traffic effects on RST. First one consisted in driving above an infrared radiometer, a pyrgeometer and other atmospheric probes to measure the radiative contribution of a passing vehicle at various speeds. In the second set, an infrared camera was installed on a vehicle in an urban traffic flow. This camera was mounted on the roof and focused the pavement right behind the vehicle ahead, both circulating at the same speed. Infrared thermography indicated a fleeting contribution of traffic to RST. The temperature increase in circulated areas, with respect to uncirculated ones, does not last according to collected measurements. Measurements with atmospheric and radiometric probes provided elements to properly take into account traffic in a numerical model and to appreciate its contribution.

  12. Right-­turn traffic volume adjustment in traffic signal warrant analysis : final report.

    Science.gov (United States)

    2016-05-06

    This report was based on the research project, Right-Turn Traffic Volume Adjustment in Traffic Signal Warrants, sponsored by the Nevada Department of Transportation (NDOT) and SOLARIS. Right-turn traffic does not affect intersection performance in th...

  13. Right-\\0xADturn traffic volume adjustment in traffic signal warrant analysis : final report.

    Science.gov (United States)

    2016-05-06

    This report was based on the research project, Right-Turn Traffic Volume Adjustment in : Traffic Signal Warrants, sponsored by the Nevada Department of Transportation (NDOT) : and SOLARIS. Right-turn traffic does not affect intersection performance i...

  14. Noise, air pollutants and traffic: continuous measurement and correlation at a high-traffic location in New York City.

    Science.gov (United States)

    Ross, Zev; Kheirbek, Iyad; Clougherty, Jane E; Ito, Kazuhiko; Matte, Thomas; Markowitz, Steven; Eisl, Holger

    2011-11-01

    Epidemiological studies have linked both noise and air pollution to common adverse health outcomes such as increased blood pressure and myocardial infarction. In urban settings, noise and air pollution share important sources, notably traffic, and several recent studies have shown spatial correlations between noise and air pollution. The temporal association between these exposures, however, has yet to be thoroughly investigated despite the importance of time series studies in air pollution epidemiology and the potential that correlations between these exposures could at least partly confound statistical associations identified in these studies. An aethelometer, for continuous elemental carbon measurement, was co-located with a continuous noise monitor near a major urban highway in New York City for six days in August 2009. Hourly elemental carbon measurements and hourly data on overall noise levels and low, medium and high frequency noise levels were collected. Hourly average concentrations of fine particles and nitrogen oxides, wind speed and direction and car, truck and bus traffic were obtained from nearby regulatory monitors. Overall temporal patterns, as well as day-night and weekday-weekend patterns, were characterized and compared for all variables. Noise levels were correlated with car, truck, and bus traffic and with air pollutants. We observed strong day-night and weekday-weekend variation in noise and air pollutants and correlations between pollutants varied by noise frequency. Medium and high frequency noise were generally more strongly correlated with traffic and traffic-related pollutants than low frequency noise and the correlation with medium and high frequency noise was generally stronger at night. Correlations with nighttime high frequency noise were particularly high for car traffic (Spearman rho=0.84), nitric oxide (0.73) and nitrogen dioxide (0.83). Wind speed and direction mediated relationships between pollutants and noise. Noise levels are

  15. Intelligent Traffic Light Based on PLC Control

    Science.gov (United States)

    Mei, Lin; Zhang, Lijian; Wang, Lingling

    2017-11-01

    The traditional traffic light system with a fixed control mode and single control function is contradicted with the current traffic section. The traditional one has been unable to meet the functional requirements of the existing flexible traffic control system. This paper research and develop an intelligent traffic light called PLC control system. It uses PLC as control core, using a sensor module for receiving real-time information of vehicles, traffic control mode for information to select the traffic lights. Of which control mode is flexible and changeable, and it also set the countdown reminder to improve the effectiveness of traffic lights, which can realize the goal of intelligent traffic diversion, intelligent traffic diversion.

  16. Traffic analysis and control using image processing

    Science.gov (United States)

    Senthilkumar, K.; Ellappan, Vijayan; Arun, A. R.

    2017-11-01

    This paper shows the work on traffic analysis and control till date. It shows an approach to regulate traffic the use of image processing and MATLAB systems. This concept uses computational images that are to be compared with original images of the street taken in order to determine the traffic level percentage and set the timing for the traffic signal accordingly which are used to reduce the traffic stoppage on traffic lights. They concept proposes to solve real life scenarios in the streets, thus enriching the traffic lights by adding image receivers like HD cameras and image processors. The input is then imported into MATLAB to be used. as a method for calculating the traffic on roads. Their results would be computed in order to adjust the traffic light timings on a particular street, and also with respect to other similar proposals but with the added value of solving a real, big instance.

  17. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, G.H.; Sterken, E.

    2002-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for bothmen and women. The historical data show that it is likely that the relation betweenskating speed and distance of the various events is non-linear and converges to a limitvalue. We pay special attention to technical

  18. Endurance in speed skating

    NARCIS (Netherlands)

    Kuper, Gerard H.; Sterken, Elmer

    2001-01-01

    We analyse the development of world records speed skating from 1893 to 2000 for both men and women. The historical data show that it is likely that the relation between skating speed and distance of the various events is non-linear and converges to a limit value. We pay special attention to

  19. Noisiness of the Surfaces on Low-Speed Roads

    Directory of Open Access Journals (Sweden)

    Wladyslaw Gardziejczyk

    2016-03-01

    Full Text Available Traffic noise is a particular threat to the environment in the vicinity of roads. The level of the noise is influenced by traffic density and traffic composition, as well as vehicle speed and the type of surface. The article presents the results of studies on tire/road noise from passing vehicles at a speed of 40–80 kph, carried out by using the statistical pass-by method (SPB, on seven surfaces with different characteristics. It has been shown that increasing the speed from 40 kph to 50 kph contributes to the increase in the maximum A-weighted sound pressure level by about 3 dB, regardless of the type of surface. For larger differences in speed (30 kph–40 kph increase in noise levels reaches values about 10 dB. In the case of higher speeds, this increase is slightly lower. In this article, special attention is paid to the noisiness from surfaces made of porous asphalt concrete (PAC, BBTM (thin asphalt layer, and stone mastic asphalt (SMA with a maximum aggregate size of 8 mm and 5 mm. It has also been proved that surfaces of porous asphalt concrete, within two years after the commissioning, significantly contribute to a reduction of the maximum level of noise in the streets and roads with lower speed of passing cars. Reduction of the maximum A-weighted sound pressure level of a statistical car traveling at 60 kph reaches values of up to about 6 dB, as compared with the SMA11. Along with the exploitation of the road, air voids in the low-noise surface becomes clogged and acoustic properties of the road decrease to a level similar to standard asphalt.

  20. A Platoon Dispersion Model Based on a Truncated Normal Distribution of Speed

    Directory of Open Access Journals (Sweden)

    Ming Wei

    2012-01-01

    Full Text Available Understanding platoon dispersion is critical for the coordination of traffic signal control in an urban traffic network. Assuming that platoon speed follows a truncated normal distribution, ranging from minimum speed to maximum speed, this paper develops a piecewise density function that describes platoon dispersion characteristics as the platoon moves from an upstream to a downstream intersection. Based on this density function, the expected number of cars in the platoon that pass the downstream intersection, and the expected number of cars in the platoon that do not pass the downstream point are calculated. To facilitate coordination in a traffic signal control system, dispersion models for the front and the rear of the platoon are also derived. Finally, a numeric computation for the coordination of successive signals is presented to illustrate the validity of the proposed model.

  1. A Dynamic Traffic Signal Timing Model and its Algorithm for Junction of Urban Road

    DEFF Research Database (Denmark)

    Cai, Yanguang; Cai, Hao

    2012-01-01

    As an important part of Intelligent Transportation System, the scientific traffic signal timing of junction can improve the efficiency of urban transport. This paper presents a novel dynamic traffic signal timing model. According to the characteristics of the model, hybrid chaotic quantum...... evolutionary algorithm is employed to solve it. The proposed model has simple structure, and only requires traffic inflow speed and outflow speed are bounded functions with at most finite number of discontinuity points. The condition is very loose and better meets the requirements of the practical real......-time and dynamic signal control of junction. To obtain the optimal solution of the model by hybrid chaotic quantum evolutionary algorithm, the model is converted to an easily solvable form. To simplify calculation, we give the expression of the partial derivative and change rate of the objective function...

  2. 4D Trajectory Estimation for Air Traffic Control Automation System Based on Hybrid System Theory

    Directory of Open Access Journals (Sweden)

    Xin-Min Tang

    2012-03-01

    Full Text Available To resolve the problem of future airspace management under great traffic flow and high density condition, 4D trajectory estimation has become one of the core technologies of the next new generation air traffic control automation system. According to the flight profile and the dynamics models of different aircraft types under different flight conditions, a hybrid system model that switches the aircraft from one flight stage to another with aircraft state changing continuously in one state is constructed. Additionally, air temperature and wind speed are used to modify aircraft true airspeed as well as ground speed, and the hybrid system evolution simulation is used to estimate aircraft 4D trajectory. The case study proves that 4D trajectory estimated through hybrid system model can image the flight dynamic states of aircraft and satisfy the needs of the planned flight altitude profile.KEY WORDSair traffic management, 4D trajectory estimation, hybrid system model, aircraft dynamic model

  3. A self-sensing carbon nanotube/cement composite for traffic monitoring

    International Nuclear Information System (INIS)

    Han Baoguo; Yu Xun; Kwon, Eil

    2009-01-01

    In this paper, a self-sensing carbon nanotube (CNT)/cement composite is investigated for traffic monitoring. The cement composite is filled with multi-walled carbon nanotubes whose piezoresistive properties enable the detection of mechanical stresses induced by traffic flow. The sensing capability of the self-sensing CNT/cement composite is explored in laboratory tests and road tests. Experimental results show that the fabricated self-sensing CNT/cement composite presents sensitive and stable responses to repeated compressive loadings and impulsive loadings, and has remarkable responses to vehicular loadings. These findings indicate that the self-sensing CNT/cement composite has great potential for traffic monitoring use, such as in traffic flow detection, weigh-in-motion measurement and vehicle speed detection.

  4. Real-time traffic sign recognition based on a general purpose GPU and deep-learning.

    Science.gov (United States)

    Lim, Kwangyong; Hong, Yongwon; Choi, Yeongwoo; Byun, Hyeran

    2017-01-01

    We present a General Purpose Graphics Processing Unit (GPGPU) based real-time traffic sign detection and recognition method that is robust against illumination changes. There have been many approaches to traffic sign recognition in various research fields; however, previous approaches faced several limitations when under low illumination or wide variance of light conditions. To overcome these drawbacks and improve processing speeds, we propose a method that 1) is robust against illumination changes, 2) uses GPGPU-based real-time traffic sign detection, and 3) performs region detecting and recognition using a hierarchical model. This method produces stable results in low illumination environments. Both detection and hierarchical recognition are performed in real-time, and the proposed method achieves 0.97 F1-score on our collective dataset, which uses the Vienna convention traffic rules (Germany and South Korea).

  5. A Study on the Model of Traffic Flow and Vehicle Exhaust Emission

    Directory of Open Access Journals (Sweden)

    Han Xue

    2013-01-01

    Full Text Available The increase of traffic flow in cities causes traffic congestion and accidents as well as air pollution. Traffic problems have attracted the interest of many researchers from the perspective of theory and engineering. In order to provide a simple and practical method for measuring the exhaust emission and assessing the effect of pollution control, a model is based on the relationship between traffic flow and vehicle exhaust emission under a certain level of road capacity constraints. In the proposed model, the hydrocarbons (HC, carbon monoxide (CO, and nitrogen oxides (NOx are considered as the indexes of total exhaust emission, and the speed is used as an intermediate variable. To verify the rationality and practicality of the model, a case study for Beijing, China, is provided in which the effects of taxi fare regulation and the specific vehicle emission reduction policy are analyzed.

  6. Relevant Affect Factors of Smartphone Mobile Data Traffic

    Directory of Open Access Journals (Sweden)

    Siniša Husnjak

    2016-08-01

    Full Text Available Smartphones are used to access a wide range of different information and communication services and perform functions based on data transfer. A number of subscription contracts for smartphones is rapidly increasing, and the development of mobile communications network provides higher speed of data transfer. The continuous increase in the average amount of data traffic per one subscriber contract leads to an increase in the total Mobile Data Traffic (MDT, globally. This research represents a summary of factors that affect the amount of smartphone MDT. Previous literature shows only a few of the factors individually that affect the realization of smartphone MDT. The results of the research clarify the ways which influence the amount of MDT generated by a smartphone. This paper increases the awareness of the users of the methods of generating smartphone MDT. The research also allows users to specify parameters that affect the prediction of generated MDT of a smartphone.

  7. Traffic analysis and signal processing in optical packet switched networks

    DEFF Research Database (Denmark)

    Fjelde, Tina

    2002-01-01

    /s optical packet switched network exploiting the best of optics and electronics, is used as a thread throughout the thesis. An overview of the DAVID network architecture is given, focussing on the MAN and WAN architecture as well as the MPLS-based network hierarchy. Subsequently, the traffic performance...... of the DAVID core optical packet router, which exploits wavelength conversion and fibre delay-line buffers for contention resolution, is analysed using a numerical model developed for that purpose. The robustness of the shared recirculating loop buffer with respect to´bursty traffic is demonstrated...... the injection of an additional clock signal into the IWC is presented. Results show very good transmission capabilities combined with a high-speed response. It is argued that signal regeneration is an inherent attribute of the IWC employed as a wavelength converter due to the sinusoidal transfer function...

  8. Performance Evaluation of 100 Gigabit Ethernet Switches under Bursty Traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Rytlig, A.; Manolova, Anna Vasileva

    2011-01-01

    Switch fabrics for 100 Gigabit Ethernet systems pose high demands in terms of delay and scalability. In this paper we analyze the performance of a Clos-based switch fabric under uniform and bursty traffic, and compare its performance to a crossbar-based switch design for benchmarking. In particular......, we focus on a Clos-design using a Space-Memory-Memory (SMM) configuration, which has recently gained increased interest due to its reduced hardware complexity. The traffic between the input and the central modules is distributed in either a static, random or Desynchronized Static Round Robin (DSRR...... switch only reveals a minor performance penalty, which can be compensated by the high scalability, robustness and low complexity of the Clos-based design for high speed switching systems....

  9. Vehicular traffic noise prediction using soft computing approach.

    Science.gov (United States)

    Singh, Daljeet; Nigam, S P; Agrawal, V P; Kumar, Maneek

    2016-12-01

    A new approach for the development of vehicular traffic noise prediction models is presented. Four different soft computing methods, namely, Generalized Linear Model, Decision Trees, Random Forests and Neural Networks, have been used to develop models to predict the hourly equivalent continuous sound pressure level, Leq, at different locations in the Patiala city in India. The input variables include the traffic volume per hour, percentage of heavy vehicles and average speed of vehicles. The performance of the four models is compared on the basis of performance criteria of coefficient of determination, mean square error and accuracy. 10-fold cross validation is done to check the stability of the Random Forest model, which gave the best results. A t-test is performed to check the fit of the model with the field data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Road safety and bicycle usage impacts of unbundling vehicular and cycle traffic in Dutch urban networks

    NARCIS (Netherlands)

    Schepers, Paul; Heinen, Eva; Methorst, Rob; Wegman, Fred

    2013-01-01

    Bicycle-motor vehicle crashes are concentrated along distributor roads where cyclists are exposed to greater volumes of high-speed motorists than they would experience on access roads. This study examined the road safety impact of network-level separation of vehicular and cycle traffic in Dutch

  11. Road safety and bicycle usage impacts of unbundling vehicular and cycle traffic in Dutch urban networks.

    NARCIS (Netherlands)

    Schepers, P. Heinen, E. Methorst, R. & Wegman, F.

    2015-01-01

    Bicycle-motor vehicle crashes are concentrated along distributor roads where cyclists are exposed to greater volumes of high-speed motorists than they would experience on access roads. This study examined the road safety impact of network-level separation of vehicular and cycle traffic in Dutch

  12. Sequential Monte Carlo simulation of collision risk in free flight air traffic

    NARCIS (Netherlands)

    Blom, H.A.P.; Bakker, G.; Krystul, J.; Everdij, M.H.C.; Klein Obbink, B.; Klompstra, M.B.

    2005-01-01

    Within HYBRIDGE a novel approach in speeding up Monte Carlo simulation of rare events has been developed. In the current report this method is extended for application to simulating collisions with a stochastic dynamical model of an air traffic operational concept. Subsequently this extended Monte

  13. Variable speed limit strategies analysis with link transmission model on urban expressway

    Science.gov (United States)

    Li, Shubin; Cao, Danni

    2018-02-01

    The variable speed limit (VSL) is a kind of active traffic management method. Most of the strategies are used in the expressway traffic flow control in order to ensure traffic safety. However, the urban expressway system is the main artery, carrying most traffic pressure. It has similar traffic characteristics with the expressways between cities. In this paper, the improved link transmission model (LTM) combined with VSL strategies is proposed, based on the urban expressway network. The model can simulate the movement of the vehicles and the shock wave, and well balance the relationship between the amount of calculation and accuracy. Furthermore, the optimal VSL strategy can be proposed based on the simulation method. It can provide management strategies for managers. Finally, a simple example is given to illustrate the model and method. The selected indexes are the average density, the average speed and the average flow on the traffic network in the simulation. The simulation results show that the proposed model and method are feasible. The VSL strategy can effectively alleviate traffic congestion in some cases, and greatly promote the efficiency of the transportation system.

  14. Structuring of Road Traffic Flows

    Directory of Open Access Journals (Sweden)

    Planko Rožić

    2005-09-01

    Full Text Available Systemic traffic count on the Croatian road network hasbeen carried out for more than three decades in different ways.During this period a large number of automatic traffic countershave been installed, and they operate on different principles.The traffic count has been analyzed from the aspect of vehicleclassification. The count results can be only partly comparedsince they yield different structures of traffic flows. Special analysisrefers to the classification of vehicles by automatic trafficcounters.During the research, a database has been formed with physicalelements of vehicles of over five thousand vehicle types. Theresearch results prove that the vehicle length only is not sufficientfor the classification of vehicles, the way it is used in thepresent automatic traffic counts, but rather the number of axles,the wheelbase as well as the front and rear overhangs needto be considered as well. Therefore, the detector system shouldapply also the detector of axles.The results have been presented that were obtained as partof the program TEST- Technological, research, developmentproject supported by the Minist1y of Science, Education andSport.

  15. Traffic noise in Hyderabad city. part I: road traffic noise

    International Nuclear Information System (INIS)

    Shaikh, G.H.; Shaikh, Q.

    2000-01-01

    Traffic noise survey was conducted at 20 sites in different areas and localities in Hyderabad city and each site noise data was collected continuously from 0800 to 2000 h. The data was analyzed for L/sub A99/, L/sub A90/, L/sub A50/, L/sub 10/ and L/sub A1/, and approximate values of L/sub Aeq12h/ were evaluated for each site. The results are discussed with reference to some criteria for community annoyance and means and ways to limit high-level traffic noise are suggested. (author)

  16. A Multi-Agent Traffic Control Model Based on Distributed System

    Directory of Open Access Journals (Sweden)

    Qian WU

    2014-06-01

    Full Text Available With the development of urbanization construction, urban travel has become a quite thorny and imminent problem. Some previous researches on the large urban traffic systems easily change into NPC problems. We purpose a multi-agent inductive control model based on the distributed approach. To describe the real traffic scene, this model designs four different types of intelligent agents, i.e. we regard each lane, route, intersection and traffic region as different types of intelligent agents. Each agent can achieve the real-time traffic data from its neighbor agents, and decision-making agents establish real-time traffic signal plans through the communication between local agents and their neighbor agents. To evaluate the traffic system, this paper takes the average delay, the stopped time and the average speed as performance parameters. Finally, the distributed multi-agent is simulated on the VISSIM simulation platform, the simulation results show that the multi-agent system is more effective than the adaptive control system in solving the traffic congestion.

  17. Carbon emissions tax policy of urban road traffic and its application in Panjin, China.

    Science.gov (United States)

    Yang, Longhai; Hu, Xiaowei; Fang, Lin

    2018-01-01

    How to effectively solve traffic congestion and transportation pollution in urban development is a main research emphasis for transportation management agencies. A carbon emissions tax can affect travelers' generalized costs and will lead to changes in passenger demand, mode choice and traffic flow equilibrium in road networks, which are of significance in green travel and low-carbon transportation management. This paper first established a mesoscopic model to calculate the carbon emissions tax and determined the value of this charge in China, which was based on road traffic flow, vehicle speed, and carbon emissions. Referring to existing research results to calibrate the value of time, this paper modified the traveler's generalized cost function, including the carbon emissions tax, fuel surcharge and travel time cost, which can be used in the travel impedance model with the consideration of the carbon emissions tax. Then, a method for analyzing urban road network traffic flow distribution was put forward, and a joint traffic distribution model was established, which considered the relationship between private cars and taxis. Finally, this paper took the city of Panjin as an example to analyze the road traffic carbon emissions tax's impact. The results illustrated that the carbon emissions tax has a positive effect on road network flow equilibrium and carbon emission reduction. This paper will have good reference value and practical significance for the calculation and implementation of urban traffic carbon emissions taxes in China.

  18. Carbon emissions tax policy of urban road traffic and its application in Panjin, China

    Science.gov (United States)

    Yang, Longhai; Fang, Lin

    2018-01-01

    How to effectively solve traffic congestion and transportation pollution in urban development is a main research emphasis for transportation management agencies. A carbon emissions tax can affect travelers’ generalized costs and will lead to changes in passenger demand, mode choice and traffic flow equilibrium in road networks, which are of significance in green travel and low-carbon transportation management. This paper first established a mesoscopic model to calculate the carbon emissions tax and determined the value of this charge in China, which was based on road traffic flow, vehicle speed, and carbon emissions. Referring to existing research results to calibrate the value of time, this paper modified the traveler’s generalized cost function, including the carbon emissions tax, fuel surcharge and travel time cost, which can be used in the travel impedance model with the consideration of the carbon emissions tax. Then, a method for analyzing urban road network traffic flow distribution was put forward, and a joint traffic distribution model was established, which considered the relationship between private cars and taxis. Finally, this paper took the city of Panjin as an example to analyze the road traffic carbon emissions tax’s impact. The results illustrated that the carbon emissions tax has a positive effect on road network flow equilibrium and carbon emission reduction. This paper will have good reference value and practical significance for the calculation and implementation of urban traffic carbon emissions taxes in China. PMID:29738580

  19. FLOW PATTERNS OF VEHICULAR TRAFFIC ALONG HIGHWAY TOLL PLAZA IN OGUN STATE

    Directory of Open Access Journals (Sweden)

    Bashiru A. Raji

    2009-06-01

    Full Text Available Congestion on our highways, freeways and arterials are increasing at an alarming rate. This occurs because there is an increase in vehicular growth without a corresponding increase in road size, and this has made free flow of traffic a preponderant problem in our highways. Toll plaza causes delay on our highways and results are formation of queue. This paper examined how simple queuing model can be used to determine traffic intensity and the flow pattern of car traffic at a toll plaza. The study was carried out with twelve field assistants at Ogere toll plaza in Ogun State. Findings show a significant variation in the degree of hourly traffic intensities at the four pay points for cars at the toll plaza. However, variation in the daily traffic intensities at the four pay points for cars showed no significant variation. The study also revealed that bumps constructed to check vehicles speed, hawker’s trading activities are among other factors that constitute hindrance to free flow of traffic other than service time and inter-arrival time of cars at the toll plaza. It is therefore recommended that appropriate authority should look into these factors and take necessary steps towards ensuring free flow of traffic at the plaza.

  20. Indirect Validation of Probe Speed Data on Arterial Corridors

    Energy Technology Data Exchange (ETDEWEB)

    Eshragh, Sepideh [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Young, Stanley E. [National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401; Sharifi, Elham [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Hamedi, Masoud [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Sadabadi, Kaveh Farokhi [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742

    2017-01-01

    This study aimed to estimate the accuracy of probe speed data on arterial corridors on the basis of roadway geometric attributes and functional classification. It was assumed that functional class (medium and low) along with other road characteristics (such as weighted average of the annual average daily traffic, average signal density, average access point density, and average speed) were available as correlation factors to estimate the accuracy of probe traffic data. This study tested these factors as predictors of the fidelity of probe traffic data by using the results of an extensive validation exercise. This study showed strong correlations between these geometric attributes and the accuracy of probe data when they were assessed by using average absolute speed error. Linear models were regressed to existing data to estimate appropriate models for medium- and low-type arterial corridors. The proposed models for medium- and low-type arterials were validated further on the basis of the results of a slowdown analysis. These models can be used to predict the accuracy of probe data indirectly in medium and low types of arterial corridors.

  1. Air Traffic Control Tools Assessment

    Directory of Open Access Journals (Sweden)

    Tomáš Noskievič

    2017-04-01

    Full Text Available Undoubtedly air transport in today’s world wouldn’t be able to exist without any air traffic control service. As the air transport has been coming through major changes and it has been expanding, it is assumed that its volume will be doubled in the next 15 years. Air traffic control uses strictly organised procedures to ensure safe course of air operations. With the skies covered with more airplanes every year, new tools must be introduced to allow the controllers to manage this rising amount of flying aircraft and to keep the air transport safe. This paper provides a comprehensive and organized material, which describes the newest tools and systems used by air traffic control officers. It proposes improvements for further research and development of ATC tools.

  2. Air traffic security act unconstitutional

    International Nuclear Information System (INIS)

    Heller, W.

    2006-01-01

    In the interest of more effective protective measures against terrorist attacks, the German federal parliament inter alia added a clause to the Air Traffic Security Act (Sec. 14, Para. 3, Air Traffic Security Act) empowering the armed forces to shoot down aircraft to be used as a weapon against human lives. In Germany, this defense possibility has been discussed also in connection with deliberate crashes of hijacked aircraft on nuclear power plants. The 1 st Division of the German Federal Constitutional Court, in its decision of February 15, 2006, ruled that Sec. 14, Para. 3, Air Traffic Security Act was incompatible with the Basic Law and thus was null and void (file No. 1 BvR 357/05) for two reasons: - There was no legislative authority on the part of the federal government. - The provision was incompatible with the basic right of life and the guarantee of human dignity as enshrined in the Basic Law. (orig.)

  3. Development of an Intelligent System of Determinating the Coordinates and the Speed of the Train

    Directory of Open Access Journals (Sweden)

    Tarasov Evgenii M.

    2016-06-01

    Full Text Available Dynamic development of the country’s transport system leads to the increase of the length of highways, traffic interchange, including places of crossing with the railway. Notification time for crossing is determined by the maximum speed of the train, which is a significant disadvantage of the automatic crossing signaling. In reality the train speed is less than the estimated one, so the idles at transport intersection (crossing reach 30-30 minutes, creating not only inconveniences to vehicle traffic, but also unfavorable environmental conditions.

  4. Traffic and Granular Flow '11

    CERN Document Server

    Buslaev, Alexander; Bugaev, Alexander; Yashina, Marina; Schadschneider, Andreas; Schreckenberg, Michael; TGF11

    2013-01-01

    This book continues the biannual series of conference proceedings, which has become a classical reference resource in traffic and granular research alike. It addresses new developments at the interface between physics, engineering and computational science. Complex systems, where many simple agents, be they vehicles or particles, give rise to surprising and fascinating phenomena.   The contributions collected in these proceedings cover several research fields, all of which deal with transport. Topics include highway, pedestrian and internet traffic, granular matter, biological transport, transport networks, data acquisition, data analysis and technological applications. Different perspectives, i.e. modeling, simulations, experiments and phenomenological observations, are considered.

  5. Reducing Traffic Congestions by Introducing CACC-Vehicles on a Multi-Lane Highway Using Agent-Based Approach

    Science.gov (United States)

    Arnaout, Georges M.; Bowling, Shannon R.

    2011-01-01

    Traffic congestion is an ongoing problem of great interest to researchers from different areas in academia. With the emerging technology for inter-vehicle communication, vehicles have the ability to exchange information with predecessors by wireless communication. In this paper, we present an agent-based model of traffic congestion and examine the impact of having CACC (Cooperative Adaptive Cruise Control) embedded vehicle(s) on a highway system consisting of 4 traffic lanes without overtaking. In our model, CACC vehicles adapt their acceleration/deceleration according to vehicle-to-vehicle inter-communication. We analyze the average speed of the cars, the shockwaves, and the evolution of traffic congestion throughout the lifecycle of the model. The study identifies how CACC vehicles affect the dynamics of traffic flow on a complex network and reduce the oscillatory behavior (stop and go) resulting from the acceleration/deceleration of the vehicles.

  6. Conflict resolution and alert zone estimation in air traffic management

    Science.gov (United States)

    Kuo, Vincent Hao-Hung

    The current air traffic control (ATC) system provides separations among all aircraft through pre-defined routes and flight procedures, and active controller participation. In particular, en route separations are achieved by choices of different flight routes, different flight levels, and speed control. During the final descent approach over an extended terminal area, aircraft separations are achieved by speed changes, altitude changes, and path stretching. Recently, a concept of free flight has been proposed for future air traffic management. In the proposed free flight environment, aircraft operators can change flight paths in real time, in order to achieve the best efficiency for the aircraft. Air traffic controllers are only supposed to intervene when situation warrants, to resolve potential conflicts among aircraft. In both cases, there is a region around each aircraft called alert zone. As soon as another aircraft touches the alert zone of own aircraft, either the own aircraft or both aircraft must initiate avoidance maneuvers to resolve a potential conflict. This thesis develops a systematic approach based on nonlinear optimal control theories to estimate alert zones in two aircraft conflict scenarios. Specifically, point-mass aircraft models are used to describe aircraft motions. Separate uses of heading, speed, and altitude control are first examined, and then the synergetic use of two control authorities are studied. Both cooperative maneuvers (in which both aircraft act) and non-cooperative maneuvers (in which the own aircraft acts alone) are considered. Optimal control problems are formulated to minimize the initial relative separation between the two aircraft for all possible initial conditions, subject to the requirement that inter-aircraft separation at any time satisfies the separation requirement. These nonlinear optimal control problems are solved numerically using a collation approach and the NPSOL software line for nonlinear programming. In

  7. Road Traffic Accidents - The Number One Killer in Libya

    Directory of Open Access Journals (Sweden)

    Abdulmajid Ahmed Ali

    2007-01-01

    Full Text Available To The Editor: It is estimated that 1.26 million people worldwide died in 2000 from road traffic accidents, 90% of them in low and middle-income countries. In 2000, the road traffic injury mortality rate for the world was 20.8 per 100,000 populations (30.8 in males, 11.0 in females [1].The Arab population constitutes 3.6% of the world’s population and it owns 1% of the world’s vehicles. Its human losses as a result of road traffic accidents (RTA account for 4.8% of that of the world’s losses [2]. It is estimated that the annual cost of road crashes is about 1% of the Gross National Product (GNP in developing countries, 1.5 in transitional countries and 2% in highly motorised countries [3].In Libya the situation is worse. It is a sad fact that road traffic accidents are the number one killer in Libya. As a matter of fact I consider it to be an ‘epidemic’ in all sectors of the Libyan society. There is not a day that goes by in Libya without us hearing about families, young men, women and children getting killed in horrific car accidents.It is alarming that young children are knocked down on a daily basis by speeding young drivers, whose understanding of driving skills may have been acquired from "playstation games"! (You can watch some of the shameful video clips sent by some of these drivers on this link http://www.youtube.com/watch?v=doWEDjiHlVoI feel it is our responsibility as physicians observing the situation to raise awareness about the scale of the problem, possible causes, and how to tackle it. POSSIBLE CAUSES:• A driving licence in Libya is not issued on the basis of how much you know. Therefore the majority of drivers know little or nothing about the law.• Wearing seat belts is not compulsory in most parts of Libya. In some places, especially in the Eastern part of Libya, you could be penalised for wearing one. I was stopped many years ago by the traffic police in the Eastern part of Libya because I was wearing sunglasses

  8. Wireless traffic steering for green cellular networks

    CERN Document Server

    Zhang, Shan; Zhou, Sheng; Niu, Zhisheng; Shen, Xuemin (Sherman)

    2016-01-01

    This book introduces wireless traffic steering as a paradigm to realize green communication in multi-tier heterogeneous cellular networks. By matching network resources and dynamic mobile traffic demand, traffic steering helps to reduce on-grid power consumption with on-demand services provided. This book reviews existing solutions from the perspectives of energy consumption reduction and renewable energy harvesting. Specifically, it explains how traffic steering can improve energy efficiency through intelligent traffic-resource matching. Several promising traffic steering approaches for dynamic network planning and renewable energy demand-supply balancing are discussed. This book presents an energy-aware traffic steering method for networks with energy harvesting, which optimizes the traffic allocated to each cell based on the renewable energy status. Renewable energy demand-supply balancing is a key factor in energy dynamics, aimed at enhancing renewable energy sustainability to reduce on-grid energy consum...

  9. Distraction-related road traffic collisions

    African Journals Online (AJOL)

    drivers involved in road traffic collisions (RTC) were using mobile phones. Our study supports ... while driving. Keywords: Distraction, prevention, road traffic collision, mobile phone. ..... keeps us connected with others with great advantages.

  10. Fuzzy Multiobjective Traffic Light Signal Optimization

    Directory of Open Access Journals (Sweden)

    N. Shahsavari Pour

    2013-01-01

    Full Text Available Traffic congestion is a major concern for many cities throughout the world. In a general traffic light controller, the traffic lights change at a constant cycle time. Hence it does not provide an optimal solution. Many traffic light controllers in current use are based on the “time-of-the-day” scheme, which use a limited number of predetermined traffic light patterns and implement these patterns depending upon the time of the day. These automated systems do not provide an optimal control for fluctuating traffic volumes. In this paper, the fuzzy traffic light controller is used to optimize the control of fluctuating traffic volumes such as oversaturated or unusual load conditions. The problem is solved by genetic algorithm, and a new defuzzification method is introduced. The performance of the new defuzzification method (NDM is compared with the centroid point defuzzification method (CPDM by using ANOVA. Finally, an illustrative example is presented to show the competency of proposed algorithm.

  11. Active Traffic Capture for Network Forensics

    Science.gov (United States)

    Slaviero, Marco; Granova, Anna; Olivier, Martin

    Network traffic capture is an integral part of network forensics, but current traffic capture techniques are typically passive in nature. Under heavy loads, it is possible for a sniffer to miss packets, which affects the quality of forensic evidence.

  12. Traffic control concepts for incident clearance

    Science.gov (United States)

    2009-01-01

    This document discusses various aspects of traffic control for incidents with the focus on the traffic control roles and responsibilities of the responders as well as the safety of the responders and the motoring public. It also recognizes that activ...

  13. High-Speed Photography

    International Nuclear Information System (INIS)

    Paisley, D.L.; Schelev, M.Y.

    1998-01-01

    The applications of high-speed photography to a diverse set of subjects including inertial confinement fusion, laser surgical procedures, communications, automotive airbags, lightning etc. are briefly discussed. (AIP) copyright 1998 Society of Photo-Optical Instrumentation Engineers

  14. Wind_Speeds_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included wind speeds for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  15. High speed data acquisition

    International Nuclear Information System (INIS)

    Cooper, P.S.

    1997-07-01

    A general introduction to high speed data acquisition system techniques in modern particle physics experiments is given. Examples are drawn from the SELEX(E78 1) high statistics charmed baryon production and decay experiment now taking data at Fermilab

  16. High speed heterostructure devices

    CERN Document Server

    Beer, Albert C; Willardson, R K; Kiehl, Richard A; Sollner, T C L Gerhard

    1994-01-01

    Volume 41 includes an in-depth review of the most important, high-speed switches made with heterojunction technology. This volume is aimed at the graduate student or working researcher who needs a broad overview andan introduction to current literature. Key Features * The first complete review of InP-based HFETs and complementary HFETs, which promise very low power and high speed * Offers a complete, three-chapter review of resonant tunneling * Provides an emphasis on circuits as well as devices.

  17. Approaches for Intelligent Traffic System: A Survey

    OpenAIRE

    Pratishtha Gupta; G.N Purohit; Amrita Dadhich

    2012-01-01

    This survey presents various approaches for intelligent traffic systems. The potential research fields in which Intelligent Traffic System emerges as an important application area are highlighted andvarious issues have been identified which need to be handled while developing such a system for an urban area, where an efficient traffic management has become the need of hour.A model is also proposed capable of managing intelligent traffic system using CCTV cameras and WAN. The proposed model wi...

  18. Physics of traffic gridlock in a city

    OpenAIRE

    Kerner, Boris S.

    2011-01-01

    Based of simulations of a stochastic three-phase traffic flow model, we reveal that at a signalized city intersection under small link inflow rates at which a vehicle queue developed during the red phase of light signal dissolves fully during the green phase, i.e., no traffic gridlock should be expected, nevertheless, traffic breakdown with the subsequent city gridlock occurs with some probability after a random time delay. This traffic breakdown is initiated by a first-order phase transition...

  19. Navigators’ Behavior in Traffic Separation Schemes

    Directory of Open Access Journals (Sweden)

    Zbigniew Pietrzykowski

    2015-03-01

    Full Text Available One of the areas of decision support in the navigational ship conduct process is a Traffic Separation Scheme. TSSs are established in areas with high traffic density, often near the shore and in port approaches. The main purpose of these schemes is to improve maritime safety by channeling vessel traffic into streams. Traffic regulations as well as ships behavior in real conditions in chosen TSSs have been analyzed in order to develop decision support algorithms.

  20. Comparison of high-speed transportation systems in special consideration of investment costs

    Directory of Open Access Journals (Sweden)

    R. Schach

    2007-10-01

    Full Text Available In this paper a substantial comparison of different high-speed transportation systems and an approach to stochastic cost estimations are provided. Starting from the developments in Europe, the high-speed traffic technical characteristics of high-speed railways and Maglev systems are compared. But for a comprehensive comparison more criterions must be included and led to a wider consideration and the development of a multi-criteria comparison of high-speed transportation systems. In the second part a stochastic approach to cost estimations of infrastructure projects is encouraged. Its advantages in comparison with the traditional proceeding are presented and exemplify the practical implementation.

  1. An LTE implementation based on a road traffic density model

    OpenAIRE

    Attaullah, Muhammad

    2013-01-01

    The increase in vehicular traffic has created new challenges in determining the behavior of performance of data and safety measures in traffic. Hence, traffic signals on intersection used as cost effective and time saving tools for traffic management in urban areas. But on the other hand the signalized intersections in congested urban areas are the key source of high traffic density and slow traffic. High traffic density causes the slow network traffic data rate between vehicle to vehicle and...

  2. Evaluating the impacts of grades on vehicular speeds on interstate highways.

    Directory of Open Access Journals (Sweden)

    Xinqiang Chen

    Full Text Available Grade variation on interstate highways affects the roadway geometric design, vehicle performance and driver behavior, thus possibly exerting an unexpected effect on vehicular speed. Hence, determining the internal relationship between grade and speed is important and useful for drivers, traffic regulators and other traffic participants. However, the problem with performing this research is the lack of large-scale gradient and speed data. Google Earth (GE provides an application programming interface for extracting elevation data worldwide. The elevation dataset from GE can be easily converted to grade data. In addition, our team has collected and stored speed series data for different freeways over several years. Based on the above obtainable grade and speed datasets, we conducted research on the effect of grades on free flow speeds from two perspectives. First, the influence of grades on speed was analyzed from both quantitative and qualitative aspects. The analysis of the distributions of four typical types of speeds demonstrated a decreasing tendency as the speed increased. Steeper grades generated a more intense speed fluctuation in terms of the four types of speeds. Second, a model based on the Student's t-test was developed to evaluate the level of significant difference among speed series under neighboring grades. The Student's t-test demonstrated that adjacent grades do not significantly influence the speeds. In summary, speeds under different grades showed obviously different tendencies. The findings of this study can help transport authorities set more reasonable speed limits and improve the geometric design of interstates with grade variation constraints.

  3. Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study.

    Science.gov (United States)

    Jarjour, Sarah; Jerrett, Michael; Westerdahl, Dane; de Nazelle, Audrey; Hanning, Cooper; Daly, Laura; Lipsitt, Jonah; Balmes, John

    2013-02-07

    A travel mode shift to active transportation such as bicycling would help reduce traffic volume and related air pollution emissions as well as promote increased physical activity level. Cyclists, however, are at risk for exposure to vehicle-related air pollutants due to their proximity to vehicle traffic and elevated respiratory rates. To promote safe bicycle commuting, the City of Berkeley, California, has designated a network of residential streets as "Bicycle Boulevards." We hypothesized that cyclist exposure to air pollution would be lower on these Bicycle Boulevards when compared to busier roads and this elevated exposure may result in reduced lung function. We recruited 15 healthy adults to cycle on two routes - a low-traffic Bicycle Boulevard route and a high-traffic route. Each participant cycled on the low-traffic route once and the high-traffic route once. We mounted pollutant monitors and a global positioning system (GPS) on the bicycles. The monitors were all synced to GPS time so pollutant measurements could be spatially plotted. We measured lung function using spirometry before and after each bike ride. We found that fine and ultrafine particulate matter, carbon monoxide, and black carbon were all elevated on the high-traffic route compared to the low-traffic route. There were no corresponding changes in the lung function of healthy non-asthmatic study subjects. We also found that wind-speed affected pollution concentrations. These results suggest that by selecting low-traffic Bicycle Boulevards instead of heavily trafficked roads, cyclists can reduce their exposure to vehicle-related air pollution. The lung function results indicate that elevated pollutant exposure may not have acute negative effects on healthy cyclists, but further research is necessary to determine long-term effects on a more diverse population. This study and broader field of research have the potential to encourage policy-makers and city planners to expand infrastructure to

  4. Actual situation analyses of rat-run traffic on community streets based on car probe data

    Science.gov (United States)

    Sakuragi, Yuki; Matsuo, Kojiro; Sugiki, Nao

    2017-10-01

    Lowering of so-called "rat-run" traffic on community streets has been one of significant challenges for improving the living environment of neighborhood. However, it has been difficult to quantitatively grasp the actual situation of rat-run traffic by the traditional surveys such as point observations. This study aims to develop a method for extracting rat-run traffic based on car probe data. In addition, based on the extracted rat-run traffic in Toyohashi city, Japan, we try to analyze the actual situation such as time and location distribution of the rat-run traffic. As a result, in Toyohashi city, the rate of using rat-run route increases in peak time period. Focusing on the location distribution of rat-run traffic, in addition, they pass through a variety of community streets. There is no great inter-district bias of the route frequently used as rat-run traffic. Next, we focused on some trips passing through a heavily used route as rat-run traffic. As a result, we found the possibility that they habitually use the route as rat-run because their trips had some commonalities. We also found that they tend to use the rat-run route due to shorter distance than using the alternative highway route, and that the travel speeds were faster than using the alternative highway route. In conclusions, we confirmed that the proposed method can quantitatively grasp the actual situation and the phenomenal tendencies of the rat-run traffic.

  5. Impacts of temporary traffic control measures on vehicular emissions during the Asian games in Guangzhou, China.

    Science.gov (United States)

    Yao, Zhiliang; Zhang, Yingzhi; Shen, Xianbao; Wang, Xintong; Wu, Ye; He, Kebin

    2013-01-01

    To guarantee good traffic and air quality during the 16th Asian Games in Guangzhou, China, the government carried out two traffic control Drills before the Games and adopted traffic control measures during the Games. Vehicle activities before and during the first and second Drills, and during the Games, were surveyed. Based on the data under investigation, the impacts of control measures on traffic volumes and driving characteristics were analyzed during the first and second Drills, and the Games. The emission reduction of traffic control measures was also evaluated during the three stages using the MOBILE-China model. The results show that there were significant effects of implementing temporary traffic control measures on transportation activity and vehicular emissions. During the first and second Drills, and the Games, the average traffic volumes in monitored roads decreased, and the average speed of vehicles increased significantly The co-effects of traffic flow reduction, traffic congestion improvement, and the banning of high-emitting vehicles helped to greatly reduce the estimated emissions from motor vehicles in Guangzhou during the first and second Drills, and the Games. Estimated vehicular emissions were reduced by 38-52% during the first Drill and 28-36% for the second Drill. During the Asian Games, vehicular emissions of carbon monoxide (CO), hydrocarbon (HC), oxides of nitrogen (NO), and particulate matter with an aerodynamic diameter vehicular emissions of CO, HC, NOx, and PM10. Motor vehicles have become the most prevalent source of emissions and subsequently air pollution within Chinese cities. Understanding the impacts that different control measures have on vehicular emissions is very important in order to be able to control vehicle emissions. The results of this study will be very helpful for the further control of vehicle emissions in Guangzhou in the future. In addition, the effects of temporary transportation control measures will provide

  6. A Spatiotemporal Multi-View-Based Learning Method for Short-Term Traffic Forecasting

    Directory of Open Access Journals (Sweden)

    Shifen Cheng

    2018-06-01

    Full Text Available Short-term traffic forecasting plays an important part in intelligent transportation systems. Spatiotemporal k-nearest neighbor models (ST-KNNs have been widely adopted for short-term traffic forecasting in which spatiotemporal matrices are constructed to describe traffic conditions. The performance of the models is closely related to the spatial dependencies, the temporal dependencies, and the interaction of spatiotemporal dependencies. However, these models use distance functions and correlation coefficients to identify spatial neighbors and measure the temporal interaction by only considering the temporal closeness of traffic, which result in existing ST-KNNs that cannot fully reflect the essential features of road traffic. This study proposes an improved spatiotemporal k-nearest neighbor model for short-term traffic forecasting by utilizing a multi-view learning algorithm named MVL-STKNN that fully considers the spatiotemporal dependencies of traffic data. First, the spatial neighbors for each road segment are automatically determined using cross-correlation under different temporal dependencies. Three spatiotemporal views are built on the constructed spatiotemporal closeness, periodic, and trend matrices to represent spatially heterogeneous traffic states. Second, a spatiotemporal weighting matrix is introduced into the ST-KNN model to recognize similar traffic patterns in the three spatiotemporal views. Finally, the results of traffic pattern recognition under these three spatiotemporal views are aggregated by using a neural network algorithm to describe the interaction of spatiotemporal dependencies. Extensive experiments were conducted using real vehicular-speed datasets collected on city roads and expressways. In comparison with baseline methods, the results show that the MVL-STKNN model greatly improves short-term traffic forecasting by lowering the mean absolute percentage error between 28.24% and 46.86% for the city road dataset and

  7. Visual Analysis in Traffic & Re-identification

    DEFF Research Database (Denmark)

    Møgelmose, Andreas

    and analysis, and person re-identification. In traffic sign detection, the work comprises a thorough survey of the state of the art, assembly of the worlds largest public dataset with U.S. traffic signs, and work in machine learning based detection algorithms. It was shown that detection of U.S. traffic signs...

  8. ReFlow: Reports on Internet Traffic

    NARCIS (Netherlands)

    Hoogesteger, Martijn; de Oliveira Schmidt, R.; Sperotto, Anna; Pras, Aiko

    Internet traffic statistics can provide valuable information to network analysts and researchers about the traffic, technologies and main characteristics of today’s networks. For many years Internet2 maintained a public website with statistics about the traffic in the Abilene network. This site was

  9. Predicting Information Flows in Network Traffic.

    Science.gov (United States)

    Hinich, Melvin J.; Molyneux, Robert E.

    2003-01-01

    Discusses information flow in networks and predicting network traffic and describes a study that uses time series analysis on a day's worth of Internet log data. Examines nonlinearity and traffic invariants, and suggests that prediction of network traffic may not be possible with current techniques. (Author/LRW)

  10. Phase diagram distortion from traffic parameter averaging.

    NARCIS (Netherlands)

    Stipdonk, H. Toorenburg, J. van & Postema, M.

    2010-01-01

    Motorway traffic congestion is a major bottleneck for economic growth. Therefore, research of traffic behaviour is carried out in many countries. Although well describing the undersaturated free flow phase as an almost straight line in a (k,q)-phase diagram, congested traffic observations and

  11. NEW POSSIBILITIES OF RAILWAY TRAFFIC CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lionginas LIUDVINAVIČIUS

    2016-06-01

    Full Text Available This article analyses the train traffic control systems in 1435 mm and 1520 mm gauge railways. The article analyses the aspects of train traffic control and locomotive energy saving by using the coordinates of track profile change that have been received from GPS. In the article, achievements of Lithuanian railways (LG in the area of train traffic control optimisation are presented.

  12. Light signals for road traffic control.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1981-01-01

    Signals for road traffic control are a major constituent of the modern traffic scene, particularly in built-up areas. A vast amount of research has been executed in the last two decennia, resulting in a fairly generally accepted view on what the requirements for effective traffic lights are. For the

  13. 30 CFR 56.9100 - Traffic control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Traffic control. 56.9100 Section 56.9100 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Dumping Traffic Safety § 56.9100 Traffic control. To provide for the safe movement of self-propelled...

  14. Traffic at risk in Mediterranean

    International Nuclear Information System (INIS)

    Bilardo, U.; Mureddu, G.

    1993-01-01

    The Mediterranean Sea represents only about 0.7% of the planet's total water surface area, yet it is host to as much as one-quarter of the world's total maritime oil traffic. Statistics indicate that from 47 to 77,000 tonnes of crude oil are now being released annually into the Sea through accidental spills; and over the last decade, its tourism dependent coastlines have been fouled by the highest levels of tar contamination in the world. Oil carrier traffic, routed within the Sea's already overcrowded shipping lanes, is intense and this traffic is expected to increase, as a result of rises in world energy demand, to levels of from 7 to 8 million barrels a day. It has been estimated that, at the end of 1992, 90% of all large tankers operating in this area, will have reached a service life of 15-16 years which is very close to the average recommended life cycle limit of 15-20 years. Only 20% of the world's 3,000 tankers are currently equipped with double bottomed hulls. This paper uses these and other facts and figures to argue that the risks of future severe oil tanker accidents in the Mediterranean Sea are high, and that these must be countered with the development of a new set of stricter marine traffic safety regulations at the Italian, national, as well as, European level

  15. The role of traffic rules.

    NARCIS (Netherlands)

    Noordzij, P.C.

    1988-01-01

    Experienced road users seem to have their own set of traffic rules (including rules about when to violate the official rules). The number of violations is enormous, causing great concern for the authorities. The situation could be improved by separating a set of rules with the aim of deterring road

  16. Learning to Detect Traffic Signs

    DEFF Research Database (Denmark)

    Møgelmose, Andreas; Trivedi, Mohan M.; Moeslund, Thomas B.

    2012-01-01

    This study compares the performance of sign detection based on synthetic training data to the performance of detection based on real-world training images. Viola-Jones detectors are created for 4 different traffic signs with both synthetic and real data, and varying numbers of training samples. T...

  17. Macroscopic models for traffic safety.

    NARCIS (Netherlands)

    Oppe, S.

    1988-01-01

    Recently there has been an increased interest in the application of macroscopic models for the description of developments in traffic safety. A discussion was started on the causes of the sudden decrease in the number of fatal and injury accidents after 1974. Before that time these numbers had

  18. Stochastic control of traffic patterns

    DEFF Research Database (Denmark)

    Gaididei, Yuri B.; Gorria, Carlos; Berkemer, Rainer

    2013-01-01

    A stochastic modulation of the safety distance can reduce traffic jams. It is found that the effect of random modulation on congestive flow formation depends on the spatial correlation of the noise. Jam creation is suppressed for highly correlated noise. The results demonstrate the advantage of h...

  19. 2008 Michigan traffic crash facts

    Science.gov (United States)

    2009-03-18

    In keeping with recent trends, traffic fatalities in 2008 were down to 980, a 9.6 : percent decrease from last year. The total number of persons injured also declined : 7.5 percent to 74,568 and total crashes dropped 2.5 percent to 316,057. Most : no...

  20. 2009 Michigan traffic crash facts

    Science.gov (United States)

    2010-01-01

    In keeping with recent trends, traffic fatalities in 2009 were down to 871, a 11.1 : percent decrease from last year. The total number of persons injured also declined : 4.9 percent to 70,931 and total crashes dropped 7.9 percent to 290,978. Most : n...

  1. Optimizing Performance of at-grade Intersection with Bus Rapid Transit Corridor and Heterogeneous Traffic

    Directory of Open Access Journals (Sweden)

    Hemant Kumar Sharma

    2012-06-01

    Full Text Available Bus Rapid Transit (BRT has emerged as a preferred mode of public transport in various countries all over the world for its cost effectiveness in construction as well as in operation and maintenance. The rapid transit feature of BRT is seen as a solution to many traffic problems in these countries. However, in developing countries like India, the right -of-way for most of the roads is restricted and traffic is heterogeneous in nature. Provision of BRT in existing right -of-way reduces the capacity available for other motorized traffic. As the buses travel with a certain frequency on dedicated bus- ways, the dedicated corridor remains unused for most of the period when other traffic on motorized vehicle (MV lanes suffers from congestion. The problem gets severe at intersections. However, if buses are operated in mixed traffic it is no more rapid transit. Hence, a solution is required to address this problem and optimize the performance of traffic as a whole. This paper presents the effect if dedicated bus-ways end at a reasonable distance before the stop line at a busy signalized at-grade intersection, and bus lanes (beyond that are made available to all the motorized vehicular traffic (heterogeneous traffic at intersection. The performance evaluation is done in terms of average queue length, maximum queue length, average delay time per vehicle, vehicle throughput, average speed in network and emission of Carbon monoxide CO, mono-nitrogen oxides NOx and Volatile organic compounds (VOC. It is observed that availability of bus lanes to other motorized traffic for a reasonable distance before intersection considerably reduces the average queue length, maximum queue length, average delay time per vehicle and emission per vehicle, while there is an increase in vehicle throughput and average speed of all the vehicles in the network. Thus it results in reduction of congestion and performance enhancement of at-grade intersections and network. Results of

  2. From Goods to Traffic:First Steps Toward an Auction-based Traffic Signal Controller

    OpenAIRE

    Raphael, Jeffery; Maskell, Simon; Sklar, Elizabeth Ida

    2015-01-01

    Traffic congestion is a major issue that plagues many urban road networks large and small. Traffic engineers are now leaning towards Intelligent Traffic Systems as many physical changes to road networks are costly or infeasible. Multi-Agent Systems (MAS) have become a popular paradigm for intelligent solutions to traffic management problems. There are many MAS approaches to traffic management that utilise market mechanisms. In market-based approaches, drivers “pay” to use the roadways. Howeve...

  3. Feature Detection of Curve Traffic Sign Image on The Bandung - Jakarta Highway

    Science.gov (United States)

    Naseer, M.; Supriadi, I.; Supangkat, S. H.

    2018-03-01

    Unsealed roadside and problems with the road surface are common causes of road crashes, particularly when those are combined with curves. Curve traffic sign is an important component for giving early warning to driver on traffic, especially on high-speed traffic like on the highway. Traffic sign detection has became a very interesting research now, and in this paper will be discussed about the detection of curve traffic sign. There are two types of curve signs are discussed, namely the curve turn to the left and the curve turn to the right and the all data sample used are the curves taken / recorded from some signs on the Bandung - Jakarta Highway. Feature detection of the curve signs use Speed Up Robust Feature (SURF) method, where the detected scene image is 800x450. From 45 curve turn to the right images, the system can detect the feature well to 35 images, where the success rate is 77,78%, while from the 45 curve turn to the left images, the system can detect the feature well to 34 images and the success rate is 75,56%, so the average accuracy in the detection process is 76,67%. While the average time for the detection process is 0.411 seconds.

  4. Evaluating the Interference of Bicycle Traffic on Vehicle Operation on Urban Streets with Bike Lanes

    Directory of Open Access Journals (Sweden)

    Ziyuan Pu

    2017-01-01

    Full Text Available Many urban streets are designed with on-street bike lanes to provide right-of-way for bicycle traffic. However, when bicycle flow is large, extensive passing maneuvers could occupy vehicle lanes and thus cause interferences to vehicle traffic. The primary objective of this study is to evaluate how bicycle traffic affects vehicle operation on urban streets with bike lanes. Data were collected on six street segments in Nanjing, China. The cumulative curves were constructed to extract traffic flow information including individual bicycle and vehicle speeds and aggregated traffic parameters such as flow and density. The results showed that as bicycle density on bike lanes continuously increases faster bicycles may run into vehicle lanes causing considerable reductions in vehicle speeds. A generalized linear model was estimated to predict the vehicle delay. Results showed that vehicle delay increases as bicycle flow and vehicle flow increase. Number of vehicle lanes and width of bike lane also have significant impact on vehicle delay. Findings of the study are helpful to regions around the world in bike infrastructure design in order to improve operations of both bicycles and vehicles.

  5. Peer influence on speeding behaviour among male drivers aged 18 and 28

    DEFF Research Database (Denmark)

    Møller, Mette; Haustein, Sonja

    2014-01-01

    related to traffic violations of male drivers. More specifically, the role of peer influence on speeding was examined in both age groups. In regression analyses it could be shown that the descriptive subjective norm, i.e. the perception of friends’ speeding, was the most important predictor of speeding...... to maintain or justify individual speeding behaviour. It is suggested that preventive measures should take these different influences of peer pressure into account by using a peer-based approach for the 18-year-olds and a more individual approach for the 28-year-olds....... with the perceived level of their friends’ speeding. In the younger age group a higher discrepancy between own and friends’ speeding was found indicating that young male drivers are socialized into increased speeding behaviour based on peer pressure. By contrast for the 28-year-olds peer pressure mainly seems...

  6. Everyone Deserves a Speeding Ticket.

    Science.gov (United States)

    Burris, Harold

    1993-01-01

    Presents a first day physics activity having students determine the fine for a speeding ticket if the speeds considered include the earth's rotation and revolution speed, and the movement through the galaxy. (MDH)

  7. Modeling the heterogeneous traffic correlations in urban road systems using traffic-enhanced community detection approach

    Science.gov (United States)

    Lu, Feng; Liu, Kang; Duan, Yingying; Cheng, Shifen; Du, Fei

    2018-07-01

    A better characterization of the traffic influence among urban roads is crucial for traffic control and traffic forecasting. The existence of spatial heterogeneity imposes great influence on modeling the extent and degree of road traffic correlation, which is usually neglected by the traditional distance based method. In this paper, we propose a traffic-enhanced community detection approach to spatially reveal the traffic correlation in city road networks. First, the road network is modeled as a traffic-enhanced dual graph with the closeness between two road segments determined not only by their topological connection, but also by the traffic correlation between them. Then a flow-based community detection algorithm called Infomap is utilized to identify the road segment clusters. Evaluated by Moran's I, Calinski-Harabaz Index and the traffic interpolation application, we find that compared to the distance based method and the community based method, our proposed traffic-enhanced community based method behaves better in capturing the extent of traffic relevance as both the topological structure of the road network and the traffic correlations among urban roads are considered. It can be used in more traffic-related applications, such as traffic forecasting, traffic control and guidance.

  8. Dividing traffic cluster into parts by signal control

    Science.gov (United States)

    Nagatani, Takashi

    2018-02-01

    When a cluster of vehicles with various speeds moves through the series of signals, the cluster breaks down by stopping at signals and results in smaller groups of vehicles. We present the nonlinear-map model of the motion of vehicles controlled by the signals. We study the breakup of a cluster of vehicles through the series of signals. The cluster of vehicles is divided into various groups by controlling the cycle time of signals. The vehicles within each group move with the same mean velocity. The breakup of the traffic cluster depends highly on the signal control. The dependence of dividing on both cycle time and vehicular speed is clarified. Also, we investigate the effect of the irregular interval between signals on dividing.

  9. Control of ribosome traffic by position-dependent choice of synonymous codons

    International Nuclear Information System (INIS)

    Mitarai, Namiko; Pedersen, Steen

    2013-01-01

    Messenger RNA (mRNA) encodes a sequence of amino acids by using codons. For most amino acids, there are multiple synonymous codons that can encode the amino acid. The translation speed can vary from one codon to another, thus there is room for changing the ribosome speed while keeping the amino acid sequence and hence the resulting protein. Recently, it has been noticed that the choice of the synonymous codon, via the resulting distribution of slow- and fast-translated codons, affects not only on the average speed of one ribosome translating the mRNA but also might have an effect on nearby ribosomes by affecting the appearance of ‘traffic jams’ where multiple ribosomes collide and form queues. To test this ‘context effect’ further, we here investigate the effect of the sequence of synonymous codons on the ribosome traffic by using a ribosome traffic model with codon-dependent rates, estimated from experiments. We compare the ribosome traffic on wild-type (WT) sequences and sequences where the synonymous codons were swapped randomly. By simulating translation of 87 genes, we demonstrate that the WT sequences, especially those with a high bias in codon usage, tend to have the ability to reduce ribosome collisions, hence optimizing the cellular investment in the translation apparatus. The magnitude of such reduction of the translation time might have a significant impact on the cellular growth rate and thereby have importance for the survival of the species. (paper)

  10. Simulation of traffic control signal systems

    Science.gov (United States)

    Connolly, P. J.; Concannon, P. A.; Ricci, R. C.

    1974-01-01

    In recent years there has been considerable interest in the development and testing of control strategies for networks of urban traffic signal systems by simulation. Simulation is an inexpensive and timely method for evaluating the effect of these traffic control strategies since traffic phenomena are too complex to be defined by analytical models and since a controlled experiment may be hazardous, expensive, and slow in producing meaningful results. This paper describes the application of an urban traffic corridor program, to evaluate the effectiveness of different traffic control strategies for the Massachusetts Avenue TOPICS Project.

  11. Traffic & rural intersection monitoring with a solar-based infrared wireless system : phase 2 final report, long term effect and justification for further analysis, May 2008 [summary].

    Science.gov (United States)

    2008-05-01

    This study concerns the development and evaluation of a dynamic speed monitoring (DSM) system for use at rural intersections. The purpose of the DSM system is to give traffic speed feedback to drivers via an advisory sign, with the goals of improving...

  12. Risk assessment on an Argentinean road with a dynamic traffic simulator

    Science.gov (United States)

    Voumard, Jérémie; Baumann, Valérie; Jaboyedoff, Michel; Derron, Marc-Henri; Penna, Ivanna

    2014-05-01

    The National Route 7 in Argentina is one of the most important corridors crossing the Andean Cordillera. It concentrates most of the traffic related to the Southern Common Market (MERCOSUR), it also connects Mendoza city (the fourth most populated in Argentina) with Santiago de Chile (the Chile capital city), and is used by tourists to access to the Aconcagua National park, Puente del Inca natural monument, skiing resorts, and to local displacements for the villages along the Mendoza valley. The road crosses the Andes through the Mendoza river valley at an elevation between 2'000 and 3'000 m. The traffic (2500 vehicles/day) is composed of motorcycles, cars and pickup trucks, trucks without trailer, buses, and semi-trailer trucks. Debris flows developed along tributaries of the Mendoza River, and due to remobilization of talus materials, impact frequently the road, causing traffic disruptions, bridges damages, etc. Rock falls detached from highly fractured outcrops also impact frequently the road, causing sometimes casualties. The aim of this study is to evaluate risk along sections of the National Road 7 develop along the Mendoza river, using a dynamic traffic simulator based on MATLAB© routine. The dynamic traffic simulator developed for natural hazards events on roads consider different scenarios based on traffic speeds, vehicle types, interactions types, road properties and natural processes. Here we show that vehicle types and traffic variations may influence the risk estimation. The analyzed risk on several critical sections of the National Route 7 demonstrates that risk may significantly increase: 1) on sinuous sections, steep sections and because of road conditions changes (exit of tunnel, bridges, road width, etc.) because of decreasing vehicle speed, particularly with semi-trailer trucks; 2) when an event, such a debris flow, occurs and generates a vehicle tailback increasing their duration presence in the risk area.

  13. A cluster analysis on road traffic accidents using genetic algorithms

    Science.gov (United States)

    Saharan, Sabariah; Baragona, Roberto

    2017-04-01

    The analysis of traffic road accidents is increasingly important because of the accidents cost and public road safety. The availability or large data sets makes the study of factors that affect the frequency and severity accidents are viable. However, the data are often highly unbalanced and overlapped. We deal with the data set of the road traffic accidents recorded in Christchurch, New Zealand, from 2000-2009 with a total of 26440 accidents. The data is in a binary set and there are 50 factors road traffic accidents with four level of severity. We used genetic algorithm for the analysis because we are in the presence of a large unbalanced data set and standard clustering like k-means algorithm may not be suitable for the task. The genetic algorithm based on clustering for unknown K, (GCUK) has been used to identify the factors associated with accidents of different levels of severity. The results provided us with an interesting insight into the relationship between factors and accidents severity level and suggest that the two main factors that contributes to fatal accidents are "Speed greater than 60 km h" and "Did not see other people until it was too late". A comparison with the k-means algorithm and the independent component analysis is performed to validate the results.

  14. An Analysis of Vehicular Traffic Flow Using Langevin Equation

    Directory of Open Access Journals (Sweden)

    Çağlar Koşun

    2015-08-01

    Full Text Available Traffic flow data are stochastic in nature, and an abundance of literature exists thereof. One way to express stochastic data is the Langevin equation. Langevin equation consists of two parts. The first part is known as the deterministic drift term, the other as the stochastic diffusion term. Langevin equation does not only help derive the deterministic and random terms of the selected portion of the city of Istanbul traffic empirically, but also sheds light on the underlying dynamics of the flow. Drift diagrams have shown that slow lane tends to get congested faster when vehicle speeds attain a value of 25 km/h, and it is 20 km/h for the fast lane. Three or four distinct regimes may be discriminated again from the drift diagrams; congested, intermediate, and free-flow regimes. At places, even the intermediate regime may be divided in two, often with readiness to congestion. This has revealed the fact that for the selected portion of the highway, there are two main states of flow, namely, congestion and free-flow, with an intermediate state where the noise-driven traffic flow forces the flow into either of the distinct regimes.

  15. Road safety and road traffic accidents in Saudi Arabia

    Science.gov (United States)

    Mansuri, Farah A.; Al-Zalabani, Abdulmohsen H.; Zalat, Marwa M.; Qabshawi, Reem I.

    2015-01-01

    Objectives: To identify the changing trends and crucial preventive approaches to road traffic accidents (RTAs) adopted in the Kingdom of Saudi Arabia (KSA) over the last 2.5 decades, and to analyze aspects previously overlooked. Methods: This systematic review was based on evidence of RTAs in KSA. All articles published during the last 25 years on road traffic accident in KSA were analyzed. This study was carried out from December 2013 to May 2014 in the Department of Family and Community Medicine, Taibah University, Al-Madinah Al-Munawwarah, KSA. Results: Road traffic accidents accounted for 83.4% of all trauma admissions in 1984-1989, and no such overall trend was studied thereafter. The most frequently injured body regions as reported in the latest studies were head and neck, followed by upper and lower extremities, which was found to be opposite to that of the studies reported earlier. Hospital data showed an 8% non-significant increase in road accident mortalities in contrast to police records of a 27% significant reduction during the years 2005-2010. Excessive speeding was the most common cause reported in all recent and past studies. Conclusion: Disparity was common in the type of reporting of RTAs, outcome measures, and possible causes over a period of 2.5 decade. All research exclusively looked into the drivers’ faults. A sentinel surveillance of road crashes should be kept in place in the secondary and tertiary care hospitals for all regions of KSA. PMID:25828277

  16. Spatial patterns monitoring of road traffic injuries in Karachi metropolis.

    Science.gov (United States)

    Lateef, Muhammad U

    2011-06-01

    This article aims to assess the pattern of road traffic injuries (RTIs) and fatalities in Karachi metropolis. Assessing the pattern of RTIs in Karachi at this juncture is important for many reasons. The rapid motorisation in the recent years due to the availability of credit has significantly increased the traffic volume of the city. Since then, the roads of Karachi have continuously developed at a rapid pace. This development has come with a high human loss, because the construction of multilevel flyovers, signal-free corridors and the resulting high-speed traffic ultimately increase the severity of injuries. The reasons for this high proportion are inadequate infrastructure, poor enforcement of safety regulations, high crash severity index and greater population of vulnerable road user groups (riders and pedestrians). This research is the first of its kind in the country to have a geocoded database of fatalities and injuries in a geographical information system for the entire city of Karachi. In fact, road crashes are both predictable and preventable. Developing countries should learn from the experience of highly motorised nations to avoid the high burden of RTIs by adopting road safety and prevention measures.

  17. Speed-volume relationship and headway distribution analysis of motorcycle (case study: Teuku Nyak Arief Road)

    Science.gov (United States)

    Prahara, E.; Prasetya, R. A.

    2018-01-01

    In many developing countries, transportation modes are more varied than the other country. For example, in Jakarta, Indonesia, in some roadway, motorcycle is the most dominant vehicle, with total volume is four times higher than a passenger car. Thus, the traffic characteristic in motorcycle-dominated traffic differs from a common traffic situation. The purpose of this study is to apply the concept and theory developed to analyze motorcycle behaviour under motorcycle-dominated traffic condition. The survey is applied by recording the traffic flow movement of research location at specified time period. The macroscopic characteristic analyzed in this research is a speed-flow relationship based on motorcycle equivalent unit (MCU). Furthermore, a detail microscopic characteristic analyzed that is motorcycle time headway regarding traffic flow. MCU values computed were consists of motorcycle (MC), light vehicle (LV) and heavy vehicle (HV). Those values were calculated 1.00, 6.13 and 10.71 respectively. The speed and volume relationship result is showing a linear regression model with R2 value is 0.58, it can be explained that the correlation between two variables is intermediate. The headway distribution of motorcycle is compatible with the negative exponential distribution which fitted with the proposed theory for a small vehicle such as a motorcycle.

  18. Vehicle speed guidance strategy at signalized intersection based on cooperative vehicle infrastructure system

    Directory of Open Access Journals (Sweden)

    Fengyuan JIA

    2017-10-01

    Full Text Available In order to reduce stopping time of vehicle at a signalized intersection, aiming at the difficulty, even the impossibility to obtain real-time queue length of intersection in third and fourth-tier cities in China sometimes, a speed guidance strategy based on cooperative vehicle infrastructure system is put forward and studied. For validating the strategy, the traffic signal timing data of the intersection at Hengshan Road and North Fengming Lake Road in Wuhu is collected by a vehicular traffic signal reminder system which is designed. The simulation experiments using the acquired data are done by software VISSIM. The simulation results demonstrate that the strategy under high and low traffic flow can effectively decrease the link travel-time, reducing average ratio is 9.2 % and 13.0 %, respectively, and the effect under low traffic flow is better than that under high traffic flow. The strategy improves efficiency of traffic at a signalized intersection and provides an idea for the application of vehicle speed guidance based on cooperative vehicle infrastructure system.

  19. TECHNICAL APPROACH TO THE EFFICIENCY DETERMINATION OF HIGH-SPEED TRAINS

    Directory of Open Access Journals (Sweden)

    A. V. Momot

    2013-11-01

    Full Text Available Purpose. The aim of this article is to develop an approach and formulate arrangements concerning the definition of the economic appropriateness of high-speed movement implementation in Ukraine. Methodology. The economic feasibility for appropriateness of high-speed movement organization in Ukraine is an investment project, which involves step-by-step money investment into the construction. It will let get an annual profits from the passenger carriage. To solve such problems we use net present value, which UZ or newly created companies can get during the project realization and after its completion. Findings. Obtained studies can state the fact that the technical approach for full effectiveness definition of a construction and high-speed passenger trains service taking into account the cost of infrastructure, rolling stock, the impact of environmental factors, etc. was determined. Originality. We propose a scientific approach to determine the economic effectiveness of the construction and high-speed main lines service. It includes improved principles of defining the passenger traffic, the cost of high-speed rails construction, the number of rolling stock; optimizes income and expenditure calculations in the context of competitive advantages and the external factors impact on the company. A technical approach for the calculation of future traffic volumes along the high-speed line was improved. It differs essentially from the European one proposed by the French firm «SYSTRA», as it allows taking into account additional transit traffic through Ukraine. It helps to distribute the passengers on separate sections proportionally to the number of cities population, which are combined by high-speed main line, subject to the average population mobility, travel time and the coefficient that takes into account the frequency of additional passenger trips on a given section, depending on the purpose (business trip, transfer to a plane, recreation, etc

  20. Changes in speed behavior due to acquired road familiarity.: A comparison between Italy and Norway

    OpenAIRE

    Intini, Paolo

    2014-01-01

    Study of traffic safety related problems concerns a lot of topics and some of them are not related only to engineering. In order to analyze accident causes it is important to comprehend the influence of human factors, as stated in most papers found in recent literature.I analyzed three areas related to human factors: risk perception, driving behaviour and speed choice. These topics are related with one another: speed choice depends on risk perception and it is involved in some driving behavio...