Sample records for traffic data

  1. Near real-time traffic routing

    NASA Technical Reports Server (NTRS)

    Yang, Chaowei (Inventor); Xie, Jibo (Inventor); Zhou, Bin (Inventor); Cao, Ying (Inventor)

    2012-01-01

    A near real-time physical transportation network routing system comprising: a traffic simulation computing grid and a dynamic traffic routing service computing grid. The traffic simulator produces traffic network travel time predictions for a physical transportation network using a traffic simulation model and common input data. The physical transportation network is divided into a multiple sections. Each section has a primary zone and a buffer zone. The traffic simulation computing grid includes multiple of traffic simulation computing nodes. The common input data includes static network characteristics, an origin-destination data table, dynamic traffic information data and historical traffic data. The dynamic traffic routing service computing grid includes multiple dynamic traffic routing computing nodes and generates traffic route(s) using the traffic network travel time predictions.

  2. Traffic information computing platform for big data

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

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn

    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.

  3. Traffic safety facts 1999 : state traffic data

    DOT National Transportation Integrated Search

    2000-01-01

    This traffic safety fact sheet presents state traffic data in a figure showing 1999 Traffic Fatalities by State and Percent Change from 1998 and in 11 tables showing: (1) Traffic Fatalities and Fatality Rates, 1999; (2) Traffic Fatalities and Percent...

  4. 32 CFR 634.30 - Use of traffic accident investigation report data.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Use of traffic accident investigation report data... § 634.30 Use of traffic accident investigation report data. (a) Data derived from traffic accident... accidents (collision diagram) will be examined. (b) Law enforcement personnel and others who prepare traffic...

  5. Joint parameter and state estimation algorithms for real-time traffic monitoring.

    DOT National Transportation Integrated Search

    2013-12-01

    A common approach to traffic monitoring is to combine a macroscopic traffic flow model with traffic sensor data in a process called state estimation, data fusion, or data assimilation. The main challenge of traffic state estimation is the integration...

  6. State Traffic Data: Traffic Safety Facts, 2001.

    ERIC Educational Resources Information Center

    National Center for Statistics and Analysis (NHTSA), Washington, DC.

    This brief provides statistical information on U.S. traffic accidents delineated by state. A map details the 2001 traffic fatalities by state and the percent change from 2000. Data tables include: (1) traffic fatalities and fatality rates, 2001; (2) traffic fatalities and percent change, 1975-2001; (3) alcohol involvement in fatal traffic crashes,…

  7. Examining Road Traffic Mortality Status in China: A Simulation Study

    PubMed Central

    Schwebel, David C.; Li, Li; Hu, Guoqing

    2016-01-01

    Background Data from the Chinese police service suggest substantial reductions in road traffic injuries since 2002, but critics have questioned the accuracy of those data, especially considering conflicting data reported by the health department. Methods To address the gap between police and health department data and to determine which may be more accurate, we conducted a simulation study based on the modified Smeed equation, which delineates a non-linear relation between road traffic mortality and the level of motorization in a country or region. Our goal was to simulate trends in road traffic mortality in China and compare performances in road traffic safety management between China and 13 other countries. Results Chinese police data indicate a peak in road traffic mortalities in 2002 and a significant and a gradual decrease in population-based road traffic mortality since 2002. Health department data show the road traffic mortality peaked in 2012. In addition, police data suggest China’s road traffic mortality peaked at a much lower motorization level (0.061 motor vehicles per person) in 2002, followed by a reduction in mortality to a level comparable to that of developed countries. Simulation results based on health department data suggest high road traffic mortality, with a mortality peak in 2012 at a moderate motorization level (0.174 motor vehicles per person). Comparisons to the other 13 countries suggest the health data from China may be more valid than the police data. Conclusion Our simulation data indicate China is still at a stage of high road traffic mortality, as suggested by health data, rather than a stage of low road traffic mortality, as suggested by police data. More efforts are needed to integrate safety into road design, improve road traffic management, improve data quality, and alter unsafe behaviors of pedestrians, drivers and passengers in China. PMID:27071008

  8. SAE for the prediction of road traffic status from taxicab operating data and bus smart card data

    NASA Astrophysics Data System (ADS)

    Zhengfeng, Huang; Pengjun, Zheng; Wenjun, Xu; Gang, Ren

    Road traffic status is significant for trip decision and traffic management, and thus should be predicted accurately. A contribution is that we consider multi-modal data for traffic status prediction than only using single source data. With the substantial data from Ningbo Passenger Transport Management Sector (NPTMS), we wished to determine whether it was possible to develop Stacked Autoencoders (SAEs) for accurately predicting road traffic status from taxicab operating data and bus smart card data. We show that SAE performed better than linear regression model and Back Propagation (BP) neural network for determining the relationship between road traffic status and those factors. In a 26-month data experiment using SAE, we show that it is possible to develop highly accurate predictions (91% test accuracy) of road traffic status from daily taxicab operating data and bus smart card data.

  9. Evaluation of the impacts of traffic states on crash risks on freeways.

    PubMed

    Xu, Chengcheng; Liu, Pan; Wang, Wei; Li, Zhibin

    2012-07-01

    The primary objective of this study is to divide freeway traffic flow into different states, and to evaluate the safety performance associated with each state. Using traffic flow data and crash data collected from a northbound segment of the I-880 freeway in the state of California, United States, K-means clustering analysis was conducted to classify traffic flow into five different states. Conditional logistic regression models using case-controlled data were then developed to study the relationship between crash risks and traffic states. Traffic flow characteristics in each traffic state were compared to identify the underlying phenomena that made certain traffic states more hazardous than others. Crash risk models were also developed for different traffic states to identify how traffic flow characteristics such as speed and speed variance affected crash risks in different traffic states. The findings of this study demonstrate that the operations of freeway traffic can be divided into different states using traffic occupancy measured from nearby loop detector stations, and each traffic state can be assigned with a certain safety level. The impacts of traffic flow parameters on crash risks are different across different traffic flow states. A method based on discriminant analysis was further developed to identify traffic states given real-time freeway traffic flow data. Validation results showed that the method was of reasonably high accuracy for identifying freeway traffic states. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Traffic safety facts 1998 : state traffic data

    DOT National Transportation Integrated Search

    1999-01-01

    This publication contains a map of the United States showing 1998 traffic fatalities by state and percent change from 1997 and eleven tables containing data on the following: (1) Traffic fatalities and fatality rates, 1998; (2) Traffic fatalities and...

  11. Assessment of Traffic-Related Noise in Three Cities in the United States

    PubMed Central

    Lee, Eunice Y.; Jerrett, Michael; Ross, Zev; Coogan, Patricia F.; Seto, Edmund Y. W.

    2014-01-01

    Background Traffic-related noise is a growing public health concern in developing and developed countries due to increasing vehicle traffic. Epidemiological studies have reported associations between noise exposure and high blood pressure, increased risk of hypertension and heart disease, and stress induced by sleep disturbance and annoyance. These findings motivate the need for regular noise assessments within urban areas. This paper assesses the relationships between traffic and noise in three US cities. Methods Noise measurements were conducted in downtown areas in three cities in the United States: Atlanta, Los Angeles, and New York City. For each city, we measured ambient noise levels, and assessed their correlation with simultaneously measured vehicle counts, and with traffic data provided by local Metropolitan Planning Organizations (MPO). Additionally, measured noise levels were compared to noise levels predicted by the Federal Highway Administration’s Traffic Noise Model using (1) simultaneously measured traffic counts or (2) MPO traffic data sources as model input. Results We found substantial variations in traffic and noise within and between cities. Total number of vehicle counts explained a substantial amount of variation in measured ambient noise in Atlanta (78%), Los Angeles (58%), and New York City (62%). Modeled noise levels were moderately correlated with measured noise levels when observed traffic counts were used as model input. Weaker correlations were found when MPO traffic data was used as model input. Conclusions Ambient noise levels measured in all three cities were correlated with traffic data, highlighting the importance of traffic planning in mitigating noise-related health effects. Model performance was sensitive to the traffic data used as input. Future noise studies that use modeled noise estimates should evaluate traffic data quality and should ideally include other factors, such as local roadway, building, and meteorological characteristics. PMID:24792415

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

    PubMed

    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.

  13. Traffic Speed Data Imputation Method Based on Tensor Completion

    PubMed Central

    Ran, Bin; 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. PMID:25866501

  14. Analysis of Yearly Traffic Fluctuation on Latvian Highways

    NASA Astrophysics Data System (ADS)

    Freimanis, A.; Paeglı¯tis, A.

    2015-11-01

    Average annual daily traffic and average annual truck traffic are two most used metrics for road management decisions. They are calculated from data gathered by continuous counting stations embedded in road pavement, manual counting sessions or mobile counting devices. Last two usually do not last longer than a couple of weeks so the information gathered is influenced by yearly traffic fluctuations. Data containing a total of 8,186,871 vehicles or 1989 days from 4 WIM stations installed on highways in Latvia were used in this study. Each of the files was supposed to contain data from only 1 day and additional data were deleted. No other data cleaning steps were performed, which increased the number of vehicles as counting systems sometimes split vehicles into two. Weekly traffic and weekly truck traffic was normalized against respective average values. Each weekly value was then plotted against its number in a year for better visual perception. Weekly traffic amplitudes were used to assess differences between different locations and standard deviations for fluctuation comparison of truck and regular traffic at the same location. Results show that truck traffic fluctuates more than regular traffic during a year, especially around holidays. Differences between counting locations were larger for regular traffic than truck traffic. These results show that average annual daily traffic could be influenced more if short term counting results are adjusted by factors derived from unsuitable continuous counting stations, but truck traffic is more influenced by the time of year in which counting is done.

  15. Risk factors associated with traffic violations and accident severity in China.

    PubMed

    Zhang, Guangnan; Yau, Kelvin K W; Chen, Guanghan

    2013-10-01

    With the recent economic boom in China, vehicle volume and the number of traffic accident fatalities have become the highest in the world. Meanwhile, traffic accidents have become the leading cause of death in China. Systematically analyzing road safety data from different perspectives and applying empirical methods/implementing proper measures to reduce the fatality rate will be an urgent and challenging task for China in the coming years. In this study, we analyze the traffic accident data for the period 2006-2010 in Guangdong Province, China. These data, extracted from the Traffic Management Sector-Specific Incident Case Data Report, are the only officially available and reliable source of traffic accident data (with a sample size>7000 per year). In particular, we focus on two outcome measures: traffic violations and accident severity. Human, vehicle, road and environmental risk factors are considered. First, the results establish the role of traffic violations as one of the major risks threatening road safety. An immediate implication is: if the traffic violation rate could be reduced or controlled successfully, then the rate of serious injuries and fatalities would be reduced accordingly. Second, specific risk factors associated with traffic violations and accident severity are determined. Accordingly, to reduce traffic accident incidence and fatality rates, measures such as traffic regulations and legislation-targeting different vehicle types/driver groups with respect to the various human, vehicle and environment risk factors-are needed. Such measures could include road safety programs for targeted driver groups, focused enforcement of traffic regulations and road/transport facility improvements. Data analysis results arising from this study will shed lights on the development of similar (adjusted) measures to reduce traffic violations and/or accident fatalities and injuries, and to promote road safety in other regions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Development of the Oregon traffic safety data archive : phases 1 and 2.

    DOT National Transportation Integrated Search

    2012-03-01

    "This report describes the preliminary work to develop the Oregon Traffic Safety Data Archive (OrTSDA). The mission of OrTSDA is to build : the knowledge base of traffic safety data in Oregon. The archive hopes to become a valuable traffic safe...

  17. Development of minimum standards for event-based data collection loggers and performance measure definitions for signalized intersections [summary].

    DOT National Transportation Integrated Search

    2017-01-01

    New traffic signal controllers, which have advanced data collection abilities, offer better information about the response of traffic signal timings to traffic flows. However, traffic engineers need more than raw data. The controllers must be set up ...

  18. Large-scale measurement and modeling of backbone Internet traffic

    NASA Astrophysics Data System (ADS)

    Roughan, Matthew; Gottlieb, Joel

    2002-07-01

    There is a brewing controversy in the traffic modeling community concerning how to model backbone traffic. The fundamental work on self-similarity in data traffic appears to be contradicted by recent findings that suggest that backbone traffic is smooth. The traffic analysis work to date has focused on high-quality but limited-scope packet trace measurements; this limits its applicability to high-speed backbone traffic. This paper uses more than one year's worth of SNMP traffic data covering an entire Tier 1 ISP backbone to address the question of how backbone network traffic should be modeled. Although the limitations of SNMP measurements do not permit us to comment on the fine timescale behavior of the traffic, careful analysis of the data suggests that irrespective of the variation at fine timescales, we can construct a simple traffic model that captures key features of the observed traffic. Furthermore, the model's parameters are measurable using existing network infrastructure, making this model practical in a present-day operational network. In addition to its practicality, the model verifies basic statistical multiplexing results, and thus sheds deep insight into how smooth backbone traffic really is.

  19. Developing a Minimum Data Set for an Information Management System to Study Traffic Accidents in Iran.

    PubMed

    Mohammadi, Ali; Ahmadi, Maryam; Gharagozlu, Alireza

    2016-03-01

    Each year, around 1.2 million people die in the road traffic incidents. Reducing traffic accidents requires an exact understanding of the risk factors associated with traffic patterns and behaviors. Properly analyzing these factors calls for a comprehensive system for collecting and processing accident data. The aim of this study was to develop a minimum data set (MDS) for an information management system to study traffic accidents in Iran. This descriptive, cross-sectional study was performed in 2014. Data were collected from the traffic police, trauma centers, medical emergency centers, and via the internet. The investigated resources for this study were forms, databases, and documents retrieved from the internet. Forms and databases were identical, and one sample of each was evaluated. The related internet-sourced data were evaluated in their entirety. Data were collected using three checklists. In order to arrive at a consensus about the data elements, the decision Delphi technique was applied using questionnaires. The content validity and reliability of the questionnaires were assessed by experts' opinions and the test-retest method, respectively. An (MDS) of a traffic accident information management system was assigned to three sections: a minimum data set for traffic police with six classes, including 118 data elements; a trauma center with five data classes, including 57 data elements; and a medical emergency center, with 11 classes, including 64 data elements. Planning for the prevention of traffic accidents requires standardized data. As the foundation for crash prevention efforts, existing standard data infrastructures present policymakers and government officials with a great opportunity to strengthen and integrate existing accident information systems to better track road traffic injuries and fatalities.

  20. Developing a Minimum Data Set for an Information Management System to Study Traffic Accidents in Iran

    PubMed Central

    Mohammadi, Ali; Ahmadi, Maryam; Gharagozlu, Alireza

    2016-01-01

    Background: Each year, around 1.2 million people die in the road traffic incidents. Reducing traffic accidents requires an exact understanding of the risk factors associated with traffic patterns and behaviors. Properly analyzing these factors calls for a comprehensive system for collecting and processing accident data. Objectives: The aim of this study was to develop a minimum data set (MDS) for an information management system to study traffic accidents in Iran. Materials and Methods: This descriptive, cross-sectional study was performed in 2014. Data were collected from the traffic police, trauma centers, medical emergency centers, and via the internet. The investigated resources for this study were forms, databases, and documents retrieved from the internet. Forms and databases were identical, and one sample of each was evaluated. The related internet-sourced data were evaluated in their entirety. Data were collected using three checklists. In order to arrive at a consensus about the data elements, the decision Delphi technique was applied using questionnaires. The content validity and reliability of the questionnaires were assessed by experts’ opinions and the test-retest method, respectively. Results: An (MDS) of a traffic accident information management system was assigned to three sections: a minimum data set for traffic police with six classes, including 118 data elements; a trauma center with five data classes, including 57 data elements; and a medical emergency center, with 11 classes, including 64 data elements. Conclusions: Planning for the prevention of traffic accidents requires standardized data. As the foundation for crash prevention efforts, existing standard data infrastructures present policymakers and government officials with a great opportunity to strengthen and integrate existing accident information systems to better track road traffic injuries and fatalities. PMID:27247791

  1. Alternative Fuels Data Center: Natural Gas Safety after a Traffic Accident

    Science.gov Websites

    Natural Gas Safety after a Traffic Accident to someone by E-mail Share Alternative Fuels Data Center: Natural Gas Safety after a Traffic Accident on Facebook Tweet about Alternative Fuels Data Center : Natural Gas Safety after a Traffic Accident on Twitter Bookmark Alternative Fuels Data Center: Natural Gas

  2. Unsupervised Ensemble Anomaly Detection Using Time-Periodic Packet Sampling

    NASA Astrophysics Data System (ADS)

    Uchida, Masato; Nawata, Shuichi; Gu, Yu; Tsuru, Masato; Oie, Yuji

    We propose an anomaly detection method for finding patterns in network traffic that do not conform to legitimate (i.e., normal) behavior. The proposed method trains a baseline model describing the normal behavior of network traffic without using manually labeled traffic data. The trained baseline model is used as the basis for comparison with the audit network traffic. This anomaly detection works in an unsupervised manner through the use of time-periodic packet sampling, which is used in a manner that differs from its intended purpose — the lossy nature of packet sampling is used to extract normal packets from the unlabeled original traffic data. Evaluation using actual traffic traces showed that the proposed method has false positive and false negative rates in the detection of anomalies regarding TCP SYN packets comparable to those of a conventional method that uses manually labeled traffic data to train the baseline model. Performance variation due to the probabilistic nature of sampled traffic data is mitigated by using ensemble anomaly detection that collectively exploits multiple baseline models in parallel. Alarm sensitivity is adjusted for the intended use by using maximum- and minimum-based anomaly detection that effectively take advantage of the performance variations among the multiple baseline models. Testing using actual traffic traces showed that the proposed anomaly detection method performs as well as one using manually labeled traffic data and better than one using randomly sampled (unlabeled) traffic data.

  3. A novel multisensor traffic state assessment system based on incomplete data.

    PubMed

    Zeng, Yiliang; Lan, Jinhui; Ran, Bin; Jiang, Yaoliang

    2014-01-01

    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.

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

    PubMed Central

    Zeng, Yiliang; Lan, Jinhui; Ran, Bin; Jiang, Yaoliang

    2014-01-01

    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. PMID:25162055

  5. A SPATIOTEMPORAL APPROACH FOR HIGH RESOLUTION TRAFFIC FLOW IMPUTATION

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

    Han, Lee; Chin, Shih-Miao; Hwang, Ho-Ling

    Along with the rapid development of Intelligent Transportation Systems (ITS), traffic data collection technologies have been evolving dramatically. The emergence of innovative data collection technologies such as Remote Traffic Microwave Sensor (RTMS), Bluetooth sensor, GPS-based Floating Car method, automated license plate recognition (ALPR) (1), etc., creates an explosion of traffic data, which brings transportation engineering into the new era of Big Data. However, despite the advance of technologies, the missing data issue is still inevitable and has posed great challenges for research such as traffic forecasting, real-time incident detection and management, dynamic route guidance, and massive evacuation optimization, because themore » degree of success of these endeavors depends on the timely availability of relatively complete and reasonably accurate traffic data. A thorough literature review suggests most current imputation models, if not all, focus largely on the temporal nature of the traffic data and fail to consider the fact that traffic stream characteristics at a certain location are closely related to those at neighboring locations and utilize these correlations for data imputation. To this end, this paper presents a Kriging based spatiotemporal data imputation approach that is able to fully utilize the spatiotemporal information underlying in traffic data. Imputation performance of the proposed approach was tested using simulated scenarios and achieved stable imputation accuracy. Moreover, the proposed Kriging imputation model is more flexible compared to current models.« less

  6. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data

    PubMed Central

    Ran, Bin; Song, Li; Cheng, Yang; Tan, Huachun

    2016-01-01

    Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%. PMID:27448326

  7. Using Tensor Completion Method to Achieving Better Coverage of Traffic State Estimation from Sparse Floating Car Data.

    PubMed

    Ran, Bin; Song, Li; Zhang, Jian; Cheng, Yang; Tan, Huachun

    2016-01-01

    Traffic state estimation from the floating car system is a challenging problem. The low penetration rate and random distribution make available floating car samples usually cover part space and time points of the road networks. To obtain a wide range of traffic state from the floating car system, many methods have been proposed to estimate the traffic state for the uncovered links. However, these methods cannot provide traffic state of the entire road networks. In this paper, the traffic state estimation is transformed to solve a missing data imputation problem, and the tensor completion framework is proposed to estimate missing traffic state. A tensor is constructed to model traffic state in which observed entries are directly derived from floating car system and unobserved traffic states are modeled as missing entries of constructed tensor. The constructed traffic state tensor can represent spatial and temporal correlations of traffic data and encode the multi-way properties of traffic state. The advantage of the proposed approach is that it can fully mine and utilize the multi-dimensional inherent correlations of traffic state. We tested the proposed approach on a well calibrated simulation network. Experimental results demonstrated that the proposed approach yield reliable traffic state estimation from very sparse floating car data, particularly when dealing with the floating car penetration rate is below 1%.

  8. 23 CFR 500.204 - TMS components for highway traffic data.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... INFRASTRUCTURE MANAGEMENT MANAGEMENT AND MONITORING SYSTEMS Traffic Monitoring System § 500.204 TMS components for highway traffic data. (a) General. Each State's TMS, including those using alternative procedures... 23 Highways 1 2010-04-01 2010-04-01 false TMS components for highway traffic data. 500.204 Section...

  9. Modeling hurricane evacuation traffic : a mobile real-time traffic counter for monitoring hurricane evacuation traffic conditions.

    DOT National Transportation Integrated Search

    2006-04-01

    The objective of this part of the research study was to select and acquire a mobile traffic counter capable of providing traffic flow and average speed data in intervals of time no greater than 15 minutes and transmit the data back to a central locat...

  10. Performance Analysis of Modified Accelerative Preallocation MAC Protocol for Passive Star-Coupled WDMA Networks

    NASA Astrophysics Data System (ADS)

    Yun, Changho; Kim, Kiseon

    2006-04-01

    For the passive star-coupled wavelength-division multiple-access (WDMA) network, a modified accelerative preallocation WDMA (MAP-WDMA) media access control (MAC) protocol is proposed, which is based on AP-WDMA. To show the advantages of MAP-WDMA as an adequate MAC protocol for the network over AP-WDMA, the channel utilization, the channel-access delay, and the latency of MAP-WDMA are investigated and compared with those of AP-WDMA under various data traffic patterns, including uniform, quasi-uniform type, disconnected type, mesh type, and ring type data traffics, as well as the assumption that a given number of network stations is equal to that of channels, in other words, without channel sharing. As a result, the channel utilization of MAP-WDMA can be competitive with respect to that of AP-WDMA at the expense of insignificantly higher latency. Namely, if the number of network stations is small, MAP-WDMA provides better channel utilization for uniform, quasi-uniform-type, and disconnected-type data traffics at all data traffic loads, as well as for mesh and ring-type data traffics at low data traffic loads. Otherwise, MAP-WDMA only outperforms AP-WDMA for the first three data traffics at higher data traffic loads. In the aspect of channel-access delay, MAP-WDMA gives better performance than AP-WDMA, regardless of data traffic patterns and the number of network stations.

  11. The importance of antipersistence for traffic jams

    NASA Astrophysics Data System (ADS)

    Krause, Sebastian M.; Habel, Lars; Guhr, Thomas; Schreckenberg, Michael

    2017-05-01

    Universal characteristics of road networks and traffic patterns can help to forecast and control traffic congestion. The antipersistence of traffic flow time series has been found for many data sets, but its relevance for congestion has been overseen. Based on empirical data from motorways in Germany, we study how antipersistence of traffic flow time-series impacts the duration of traffic congestion on a wide range of time scales. We find a large number of short-lasting traffic jams, which implies a large risk for rear-end collisions.

  12. Wisconsin's approach to variation in traffic data

    DOT National Transportation Integrated Search

    2000-08-01

    Traffic data exhibits considerable variability, both spatially and temporally. Given limited resources and the large geographic coverage required for data collection efforts, short period (24-hours to 7-day) traffic data collection must often serve t...

  13. A Hidden Markov Model for Urban-Scale Traffic Estimation Using Floating Car Data.

    PubMed

    Wang, Xiaomeng; Peng, Ling; Chi, Tianhe; Li, Mengzhu; Yao, Xiaojing; Shao, Jing

    2015-01-01

    Urban-scale traffic monitoring plays a vital role in reducing traffic congestion. Owing to its low cost and wide coverage, floating car data (FCD) serves as a novel approach to collecting traffic data. However, sparse probe data represents the vast majority of the data available on arterial roads in most urban environments. In order to overcome the problem of data sparseness, this paper proposes a hidden Markov model (HMM)-based traffic estimation model, in which the traffic condition on a road segment is considered as a hidden state that can be estimated according to the conditions of road segments having similar traffic characteristics. An algorithm based on clustering and pattern mining rather than on adjacency relationships is proposed to find clusters with road segments having similar traffic characteristics. A multi-clustering strategy is adopted to achieve a trade-off between clustering accuracy and coverage. Finally, the proposed model is designed and implemented on the basis of a real-time algorithm. Results of experiments based on real FCD confirm the applicability, accuracy, and efficiency of the model. In addition, the results indicate that the model is practicable for traffic estimation on urban arterials and works well even when more than 70% of the probe data are missing.

  14. Towards a Cloud Based Smart Traffic Management Framework

    NASA Astrophysics Data System (ADS)

    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.

  15. 32 CFR 634.30 - Use of traffic accident investigation report data.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Use of traffic accident investigation report... § 634.30 Use of traffic accident investigation report data. (a) Data derived from traffic accident investigation reports and from vehicle owner accident reports will be analyzed to determine probable causes of...

  16. Integrating intersection traffic signal data into a traffic monitoring program.

    DOT National Transportation Integrated Search

    2014-09-01

    The objective of this study was to provide the Georgia Department of Transportation with : an evaluation of the feasibility of integrating intersection traffic signal data into a traffic : monitoring program. Some of the pertinent conclusions from th...

  17. Dynamic baseline detection method for power data network service

    NASA Astrophysics Data System (ADS)

    Chen, Wei

    2017-08-01

    This paper proposes a dynamic baseline Traffic detection Method which is based on the historical traffic data for the Power data network. The method uses Cisco's NetFlow acquisition tool to collect the original historical traffic data from network element at fixed intervals. This method uses three dimensions information including the communication port, time, traffic (number of bytes or number of packets) t. By filtering, removing the deviation value, calculating the dynamic baseline value, comparing the actual value with the baseline value, the method can detect whether the current network traffic is abnormal.

  18. A System for Traffic Violation Detection

    PubMed Central

    Aliane, Nourdine; Fernandez, Javier; Mata, Mario; Bemposta, Sergio

    2014-01-01

    This paper describes the framework and components of an experimental platform for an advanced driver assistance system (ADAS) aimed at providing drivers with a feedback about traffic violations they have committed during their driving. The system is able to detect some specific traffic violations, record data associated to these faults in a local data-base, and also allow visualization of the spatial and temporal information of these traffic violations in a geographical map using the standard Google Earth tool. The test-bed is mainly composed of two parts: a computer vision subsystem for traffic sign detection and recognition which operates during both day and nighttime, and an event data recorder (EDR) for recording data related to some specific traffic violations. The paper covers firstly the description of the hardware architecture and then presents the policies used for handling traffic violations. PMID:25421737

  19. A system for traffic violation detection.

    PubMed

    Aliane, Nourdine; Fernandez, Javier; Mata, Mario; Bemposta, Sergio

    2014-11-24

    This paper describes the framework and components of an experimental platform for an advanced driver assistance system (ADAS) aimed at providing drivers with a feedback about traffic violations they have committed during their driving. The system is able to detect some specific traffic violations, record data associated to these faults in a local data-base, and also allow visualization of the spatial and temporal information of these traffic violations in a geographical map using the standard Google Earth tool. The test-bed is mainly composed of two parts: a computer vision subsystem for traffic sign detection and recognition which operates during both day and nighttime, and an event data recorder (EDR) for recording data related to some specific traffic violations. The paper covers firstly the description of the hardware architecture and then presents the policies used for handling traffic violations.

  20. Traffic safety facts 1994 : state traffic data

    DOT National Transportation Integrated Search

    1995-01-01

    Nationwide in 1994, traffic fatalities were up 1 percent for a total of 40,676 traffic deaths. These tables provide summary data of fatal crashes for the United States and individually for the 50 states, the District of Columbia, and Puerto Rico (not...

  1. Development of a traffic data input system in Arizona for the MEPDG.

    DOT National Transportation Integrated Search

    2013-10-01

    Accurate traffic data is one of the key data elements required for the cost-effective design of all rehabilitation and reconstruction of : pavement structures. This research study addresses the collection, preparation, and use of traffic data require...

  2. Use of mobile data for weather-responsive traffic management models.

    DOT National Transportation Integrated Search

    2012-10-01

    The evolution of telecommunications and wireless technologies has brought in new sources of traffic data (particularly mobile data generated by vehicle probes), which could offer a breakthrough in the quality and extent of traffic data. This study re...

  3. Defining and measuring traffic data quality traffic data quality workshop : white paper.

    DOT National Transportation Integrated Search

    2002-12-31

    Recent research and analyses have identified several issues regarding the quality of traffic data available from intelligent transportation systems for transportation operations, planning, or other functions. The Federal Highway Administration (FHWA)...

  4. Exploratory statistical and geographical freight traffic data analysis

    DOT National Transportation Integrated Search

    2000-08-01

    Data from freight traffic roadside surveys in Mexican highways are analyzed in order to find consistent patterns or systematic relationships between variables characterizing this traffic. Patterns traced are validated by contrasting against new data ...

  5. Use of permanent traffic recorder data to develop factors for traffic and truck variations

    DOT National Transportation Integrated Search

    2002-10-01

    This project entailed the development of the following four traffic volume adjustment factors from 1995 and 1996 permanent traffic recorder data: (1) A truck (axle) adjustment factor for single pneumatic tube counters; (2) A factor for estimating Des...

  6. Traffic Congestion Detection System through Connected Vehicles and Big Data

    PubMed Central

    Cárdenas-Benítez, Néstor; Aquino-Santos, Raúl; Magaña-Espinoza, Pedro; Aguilar-Velazco, José; Edwards-Block, Arthur; Medina Cass, Aldo

    2016-01-01

    This article discusses the simulation and evaluation of a traffic congestion detection system which combines inter-vehicular communications, fixed roadside infrastructure and infrastructure-to-infrastructure connectivity and big data. The system discussed in this article permits drivers to identify traffic congestion and change their routes accordingly, thus reducing the total emissions of CO2 and decreasing travel time. This system monitors, processes and stores large amounts of data, which can detect traffic congestion in a precise way by means of a series of algorithms that reduces localized vehicular emission by rerouting vehicles. To simulate and evaluate the proposed system, a big data cluster was developed based on Cassandra, which was used in tandem with the OMNeT++ discreet event network simulator, coupled with the SUMO (Simulation of Urban MObility) traffic simulator and the Veins vehicular network framework. The results validate the efficiency of the traffic detection system and its positive impact in detecting, reporting and rerouting traffic when traffic events occur. PMID:27136548

  7. Traffic Congestion Detection System through Connected Vehicles and Big Data.

    PubMed

    Cárdenas-Benítez, Néstor; Aquino-Santos, Raúl; Magaña-Espinoza, Pedro; Aguilar-Velazco, José; Edwards-Block, Arthur; Medina Cass, Aldo

    2016-04-28

    This article discusses the simulation and evaluation of a traffic congestion detection system which combines inter-vehicular communications, fixed roadside infrastructure and infrastructure-to-infrastructure connectivity and big data. The system discussed in this article permits drivers to identify traffic congestion and change their routes accordingly, thus reducing the total emissions of CO₂ and decreasing travel time. This system monitors, processes and stores large amounts of data, which can detect traffic congestion in a precise way by means of a series of algorithms that reduces localized vehicular emission by rerouting vehicles. To simulate and evaluate the proposed system, a big data cluster was developed based on Cassandra, which was used in tandem with the OMNeT++ discreet event network simulator, coupled with the SUMO (Simulation of Urban MObility) traffic simulator and the Veins vehicular network framework. The results validate the efficiency of the traffic detection system and its positive impact in detecting, reporting and rerouting traffic when traffic events occur.

  8. Feasibility study for using video detection system data to supplement automatic traffic recorder data.

    DOT National Transportation Integrated Search

    2013-12-01

    The objective of this study was to determine the feasibility of incorporating Georgia NaviGAtor : traffic volume data with Georgia Department of Transportation (GDOT) traffic volume data to : enhance federal reporting. Some of the pertinent conclusio...

  9. Real-Time SCADA Cyber Protection Using Compression Techniques

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

    Lyle G. Roybal; Gordon H Rueff

    2013-11-01

    The Department of Energy’s Office of Electricity Delivery and Energy Reliability (DOE-OE) has a critical mission to secure the energy infrastructure from cyber attack. Through DOE-OE’s Cybersecurity for Energy Delivery Systems (CEDS) program, the Idaho National Laboratory (INL) has developed a method to detect malicious traffic on Supervisory, Control, and Data Acquisition (SCADA) network using a data compression technique. SCADA network traffic is often repetitive with only minor differences between packets. Research performed at the INL showed that SCADA network traffic has traits desirable for using compression analysis to identify abnormal network traffic. An open source implementation of a Lempel-Ziv-Welchmore » (LZW) lossless data compression algorithm was used to compress and analyze surrogate SCADA traffic. Infected SCADA traffic was found to have statistically significant differences in compression when compared against normal SCADA traffic at the packet level. The initial analyses and results are clearly able to identify malicious network traffic from normal traffic at the packet level with a very high confidence level across multiple ports and traffic streams. Statistical differentiation between infected and normal traffic level was possible using a modified data compression technique at the 99% probability level for all data analyzed. However, the conditions tested were rather limited in scope and need to be expanded into more realistic simulations of hacking events using techniques and approaches that are better representative of a real-world attack on a SCADA system. Nonetheless, the use of compression techniques to identify malicious traffic on SCADA networks in real time appears to have significant merit for infrastructure protection.« less

  10. Aggregated GPS tracking of vehicles and its use as a proxy of traffic-related air pollution emissions

    NASA Astrophysics Data System (ADS)

    Chen, Shimon; Bekhor, Shlomo; Yuval; Broday, David M.

    2016-10-01

    Most air quality models use traffic-related variables as an input. Previous studies estimated nearby vehicular activity through sporadic traffic counts or via traffic assignment models. Both methods have previously produced poor or no data for nights, weekends and holidays. Emerging technologies allow the estimation of traffic through passive monitoring of location-aware devices. Examples of such devices are GPS transceivers installed in vehicles. In this work, we studied traffic volumes that were derived from such data. Additionally, we used these data for estimating ambient nitrogen dioxide concentrations, using a non-linear optimisation model that includes basic dispersion properties. The GPS-derived data show great potential for use as a proxy for pollutant emissions from motor-vehicles.

  11. Small-time Scale Network Traffic Prediction Based on Complex-valued Neural Network

    NASA Astrophysics Data System (ADS)

    Yang, Bin

    2017-07-01

    Accurate models play an important role in capturing the significant characteristics of the network traffic, analyzing the network dynamic, and improving the forecasting accuracy for system dynamics. In this study, complex-valued neural network (CVNN) model is proposed to further improve the accuracy of small-time scale network traffic forecasting. Artificial bee colony (ABC) algorithm is proposed to optimize the complex-valued and real-valued parameters of CVNN model. Small-scale traffic measurements data namely the TCP traffic data is used to test the performance of CVNN model. Experimental results reveal that CVNN model forecasts the small-time scale network traffic measurement data very accurately

  12. Understanding the T2 traffic in CMS during Run-1

    NASA Astrophysics Data System (ADS)

    T, Wildish

    2015-12-01

    In the run-up to Run-1 CMS was operating its facilities according to the MONARC model, where data-transfers were strictly hierarchical in nature. Direct transfers between Tier-2 nodes was excluded, being perceived as operationally intensive and risky in an era where the network was expected to be a major source of errors. By the end of Run-1 wide-area networks were more capable and stable than originally anticipated. The original data-placement model was relaxed, and traffic was allowed between Tier-2 nodes. Tier-2 to Tier-2 traffic in 2012 already exceeded the amount of Tier-2 to Tier-1 traffic, so it clearly has the potential to become important in the future. Moreover, while Tier-2 to Tier-1 traffic is mostly upload of Monte Carlo data, the Tier-2 to Tier-2 traffic represents data moved in direct response to requests from the physics analysis community. As such, problems or delays there are more likely to have a direct impact on the user community. Tier-2 to Tier-2 traffic may also traverse parts of the WAN that are at the 'edge' of our network, with limited network capacity or reliability compared to, say, the Tier-0 to Tier-1 traffic which goes the over LHCOPN network. CMS is looking to exploit technologies that allow us to interact with the network fabric so that it can manage our traffic better for us, this we hope to achieve before the end of Run-2. Tier-2 to Tier-2 traffic would be the most interesting use-case for such traffic management, precisely because it is close to the users' analysis and far from the 'core' network infrastructure. As such, a better understanding of our Tier-2 to Tier-2 traffic is important. Knowing the characteristics of our data-flows can help us place our data more intelligently. Knowing how widely the data moves can help us anticipate the requirements for network capacity, and inform the dynamic data placement algorithms we expect to have in place for Run-2. This paper presents an analysis of the CMS Tier-2 traffic during Run 1.

  13. Long term pavement performance program protocol for calibrating traffic data collection equipment

    DOT National Transportation Integrated Search

    1998-05-10

    This document describes the procedures that the Long Term Pavement Performance (LTPP) program recommends for ensuring that traffic data collection equipment used for LTPP traffic monitoring efforts operates correctly and collects valid data.

  14. Evaluation of LADOTD traffic load data for determination of traffic load equivalency factors : technical summary.

    DOT National Transportation Integrated Search

    2002-04-01

    Louisianan has established a traffic monitoring program, compliant with FHWA incentives, that is designed to collect and manage the traffic data needed for the design and management of LADOTD's network of current and future highways. In the early 198...

  15. Estimating AADT from combined air photos and ground based data : system design, prototyping, and testing.

    DOT National Transportation Integrated Search

    2009-09-15

    Average annual daily traffic (AADT) is perhaps the most fundamental measure of traffic flow. The data used to produce AADT estimates are largely collected by in-highway traffic counters operated by traffic monitoring crews who must cover thousands of...

  16. Citizen Science for Traffic Planning: A Practical Example

    NASA Astrophysics Data System (ADS)

    Rieke, Matthes; Stasch, Christoph; Autermann, Christian; de Wall, Arne; Remke, Albert; Wulffius, Herwig; Jirka, Simon

    2017-04-01

    Measures affecting traffic flows in urban areas, e.g. changing the configuration of traffic lights, are often causing emotional debates by citizens who are affected by these measures. Up to now, citizens are usually not involved in traffic planning and the evaluation of the decisions that were taken. The enviroCar project provides an open platform for collecting and analyzing car sensor data with GPS position data. On the hardware side, enviroCar relies on using Android smartphones and OBD-II Bluetooth adapters. A Web server component collects and aggregates the readings from the cars, anonymizes them and publishes the data as open data which scientists, public administrations or other third parties can utilize for further analysis. In this work, we provide a general overview on the enviroCar project and present a project in a mid-size city in Germany. The city's administration utilized the enviroCar platform with the help of a traffic system consultancy for including citizens in the evaluation process of different traffic light configurations along major traffic axes. Therefore, a public campaign was started including local workshops to engage the citizens. More than 150 citizens were actively collecting more about 9.500 tracks including about 2.5 million measurements. Dedicated evaluation results for the different traffic axes were computed based on the collected data set. Because the data is publicly available as open data, others may prove and reproduce the evaluation results contributing to an objective discussion of traffic planning measures. In summary, the project illustrates how Citizen Science methods and technologies improve traffic planning and related discussions.

  17. Traffic management simulation development : summary.

    DOT National Transportation Integrated Search

    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...

  18. Integrating traffic management data via an enterprise LRS

    DOT National Transportation Integrated Search

    2000-06-01

    A Geographic Information System for Transportation (GIS-T) can be a powerful tool to integrate traffic data with other data and help analyze results for transportation decision-making (e.g., program, traffic, or safety management). For successful GIS...

  19. Traffic Safety Facts, 2001: Pedalcylists.

    ERIC Educational Resources Information Center

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

    This document provides statistical information on traffic accidents involving U.S. bicyclists. Data include: (1) trends in pedalcyclist and total traffic fatalities, 1991-2001; (2) non-occupant traffic fatalities, 1991-2001; (3) pedalcyclists killed and injured, and fatality and injury rates, by age and sex, 2000 [2001 population data by age group…

  20. A Cyber-ITS Framework for Massive Traffic Data Analysis Using Cyber Infrastructure

    PubMed Central

    Fontaine, Michael D.

    2013-01-01

    Traffic data is commonly collected from widely deployed sensors in urban areas. This brings up a new research topic, data-driven intelligent transportation systems (ITSs), which means to integrate heterogeneous traffic data from different kinds of sensors and apply it for ITS applications. This research, taking into consideration the significant increase in the amount of traffic data and the complexity of data analysis, focuses mainly on the challenge of solving data-intensive and computation-intensive problems. As a solution to the problems, this paper proposes a Cyber-ITS framework to perform data analysis on Cyber Infrastructure (CI), by nature parallel-computing hardware and software systems, in the context of ITS. The techniques of the framework include data representation, domain decomposition, resource allocation, and parallel processing. All these techniques are based on data-driven and application-oriented models and are organized as a component-and-workflow-based model in order to achieve technical interoperability and data reusability. A case study of the Cyber-ITS framework is presented later based on a traffic state estimation application that uses the fusion of massive Sydney Coordinated Adaptive Traffic System (SCATS) data and GPS data. The results prove that the Cyber-ITS-based implementation can achieve a high accuracy rate of traffic state estimation and provide a significant computational speedup for the data fusion by parallel computing. PMID:23766690

  1. A Cyber-ITS framework for massive traffic data analysis using cyber infrastructure.

    PubMed

    Xia, Yingjie; Hu, Jia; Fontaine, Michael D

    2013-01-01

    Traffic data is commonly collected from widely deployed sensors in urban areas. This brings up a new research topic, data-driven intelligent transportation systems (ITSs), which means to integrate heterogeneous traffic data from different kinds of sensors and apply it for ITS applications. This research, taking into consideration the significant increase in the amount of traffic data and the complexity of data analysis, focuses mainly on the challenge of solving data-intensive and computation-intensive problems. As a solution to the problems, this paper proposes a Cyber-ITS framework to perform data analysis on Cyber Infrastructure (CI), by nature parallel-computing hardware and software systems, in the context of ITS. The techniques of the framework include data representation, domain decomposition, resource allocation, and parallel processing. All these techniques are based on data-driven and application-oriented models and are organized as a component-and-workflow-based model in order to achieve technical interoperability and data reusability. A case study of the Cyber-ITS framework is presented later based on a traffic state estimation application that uses the fusion of massive Sydney Coordinated Adaptive Traffic System (SCATS) data and GPS data. The results prove that the Cyber-ITS-based implementation can achieve a high accuracy rate of traffic state estimation and provide a significant computational speedup for the data fusion by parallel computing.

  2. Traffic safety data : state data system quality varies and limited resources and coordination can inhibit further progress

    DOT National Transportation Integrated Search

    2010-04-01

    GAOs analysis of traffic records assessmentsconducted for states by NHTSA technical teams or contractors at least every 5 yearsindicates that the quality of state traffic safety data systems varies across the six data systems maintained by s...

  3. Assessment of traffic noise levels in urban areas using different soft computing techniques.

    PubMed

    Tomić, J; Bogojević, N; Pljakić, M; Šumarac-Pavlović, D

    2016-10-01

    Available traffic noise prediction models are usually based on regression analysis of experimental data, and this paper presents the application of soft computing techniques in traffic noise prediction. Two mathematical models are proposed and their predictions are compared to data collected by traffic noise monitoring in urban areas, as well as to predictions of commonly used traffic noise models. The results show that application of evolutionary algorithms and neural networks may improve process of development, as well as accuracy of traffic noise prediction.

  4. [Hospital information system performance for road traffic accidents analysis in a hospital recruitment based area].

    PubMed

    Jannot, A-S; Fauconnier, J

    2013-06-01

    Road traffic accidents in France are mainly analyzed through reports completed by the security forces (police and gendarmerie). But the hospital information systems can also identify road traffic accidents via specific documentary codes of the International Classification of Diseases (ICD-10). The aim of this study was therefore to determine whether hospital stays consecutive to road traffic accident were truly identified by these documentary codes in a facility that collects data routinely and to study the consistency of results from hospital information systems and from security forces during the 2002-2008 period. We retrieved all patients for whom a documentary code for road traffic accident was entered in 2002-2008. We manually checked the concordance of documentary code for road traffic accident and trauma origin in 350 patient files. The number of accidents in the Grenoble area was then inferred by combining with hospitalization regional data and compared to the number of persons injured by traffic accidents declared by the security force. These hospital information systems successfully report road traffic accidents with 96% sensitivity (95%CI: [92%, 100%]) and 97% specificity (95%CI: [95%, 99%]). The decrease in road traffic accidents observed was significantly less than that observed was significantly lower than that observed in the data from the security force (45% for security force data against 27% for hospital data). Overall, this study shows that hospital information systems are a powerful tool for studying road traffic accidents morbidity in hospital and are complementary to security force data. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  5. Ohio traffic crash facts, 1994

    DOT National Transportation Integrated Search

    1994-01-01

    Information contained in this report represents traffic crash data and supporting information : from the Ohio Integrated Traffic Records System and various other state agency sources. : Data presented herein represents the contents of those files on ...

  6. 2006 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2007-06-01

    The Crash Analysis and Reporting Unit compiles data for reported motor vehicle traffic crashes occurring : on city streets, county roads and state highways. The data supports various local, county and state traffic : safety programs, engineering and ...

  7. 2007 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2008-07-01

    The Crash Analysis and Reporting Unit compiles data for reported motor vehicle traffic crashes occurring : on city streets, county roads and state highways. The data supports various local, county and state traffic : safety programs, engineering and ...

  8. Ohio traffic crash facts, 2003

    DOT National Transportation Integrated Search

    2004-04-28

    Information contained in this report represents traffic crash data and supporting information from the : Ohio Integrated Traffic Records System (ITRS) for the calendar year 2003. Data presented herein : represents the crash report forms as submitted ...

  9. Ohio traffic crash facts, 2005

    DOT National Transportation Integrated Search

    2006-04-01

    Information contained in this report represents traffic crash data and supporting information from the : Ohio Integrated Traffic Records System (ITRS) for the calendar year 2005. Data presented herein : represents the crash report forms as submitted ...

  10. Ohio traffic crash facts, 2002

    DOT National Transportation Integrated Search

    2003-12-01

    Information contained in this report represents traffic crash data and supporting information from the : Ohio Integrated Traffic Records System (ITRS) for the calendar year 2002. Data presented herein : represents the crash report forms as submitted ...

  11. Ohio traffic crash facts, 2004

    DOT National Transportation Integrated Search

    2005-04-14

    Information contained in this report represents traffic crash data and supporting information from the : Ohio Integrated Traffic Records System (ITRS) for the calendar year 2004. Data presented herein : represents the crash report forms as submitted ...

  12. Ohio traffic crash facts, 2006

    DOT National Transportation Integrated Search

    2007-07-01

    Information contained in this report represents traffic crash data and supporting information from the Ohio : Integrated Traffic Records System (ITRS) for the calendar year 2006. Data presented herein represents the : crash report forms as submitted ...

  13. Ohio traffic crash facts, 1997

    DOT National Transportation Integrated Search

    1998-07-01

    Information contained in this report represents traffic crash data and supporting information : from the Ohio Integrated Traffic Records System and various other state agency sources. : Data presented herein represents the contents of those files on ...

  14. Ohio traffic crash facts, 1998

    DOT National Transportation Integrated Search

    1999-01-01

    Information contained in this report represents traffic crash data and supporting information : from the Ohio Integrated Traffic Records System and various other state agency sources. : Data presented herein represents the contents of those files on ...

  15. Ohio traffic crash facts, 1999

    DOT National Transportation Integrated Search

    2000-07-01

    Information contained in this report represents traffic crash data and supporting information : from the Ohio Integrated Traffic Records System and various other state agency sources. : Data presented herein represents the contents of those files on ...

  16. Ohio traffic crash facts, 2001

    DOT National Transportation Integrated Search

    2002-06-05

    Information contained in this report represents traffic crash data and supporting information from the Ohio : Integrated Traffic Records System (ITRS) for the calendar year 2001. Data presented herein represents the : crash report forms as submitted ...

  17. Traffic management simulation development.

    DOT National Transportation Integrated Search

    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...

  18. 2005 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2006-06-01

    The Crash Analysis and Reporting Unit compiles data for reported motor vehicle traffic crashes occurring : on city streets, county roads and state highways. The data supports various local, county and state traffic : safety programs, engineering and ...

  19. State of the practice for traffic data quality : traffic data quality workshop : white paper.

    DOT National Transportation Integrated Search

    2002-12-31

    This White Paper documents the current state of the practice in the quality of traffic data generated by Intelligent Transportation Systems (ITS). The current state of the practice is viewed from the perspectives of both Operations and Planning perso...

  20. Mobile Traffic Alert and Tourist Route Guidance System Design Using Geospatial Data

    NASA Astrophysics Data System (ADS)

    Bhattacharya, D.; Painho, M.; Mishra, S.; Gupta, A.

    2017-09-01

    The present study describes an integrated system for traffic data collection and alert warning. Geographical information based decision making related to traffic destinations and routes is proposed through the design. The system includes a geospatial database having profile relating to a user of a mobile device. The processing and understanding of scanned maps, other digital data input leads to route guidance. The system includes a server configured to receive traffic information relating to a route and location information relating to the mobile device. Server is configured to send a traffic alert to the mobile device when the traffic information and the location information indicate that the mobile device is traveling toward traffic congestion. Proposed system has geospatial and mobile data sets pertaining to Bangalore city in India. It is envisaged to be helpful for touristic purposes as a route guidance and alert relaying information system to tourists for proximity to sites worth seeing in a city they have entered into. The system is modular in architecture and the novelty lies in integration of different modules carrying different technologies for a complete traffic information system. Generic information processing and delivery system has been tested to be functional and speedy under test geospatial domains. In a restricted prototype model with geo-referenced route data required information has been delivered correctly over sustained trials to designated cell numbers, with average time frame of 27.5 seconds, maximum 50 and minimum 5 seconds. Traffic geo-data set trials testing is underway.

  1. Global Simulation of Aviation Operations

    NASA Technical Reports Server (NTRS)

    Sridhar, Banavar; Sheth, Kapil; Ng, Hok Kwan; Morando, Alex; Li, Jinhua

    2016-01-01

    The simulation and analysis of global air traffic is limited due to a lack of simulation tools and the difficulty in accessing data sources. This paper provides a global simulation of aviation operations combining flight plans and real air traffic data with historical commercial city-pair aircraft type and schedule data and global atmospheric data. The resulting capability extends the simulation and optimization functions of NASA's Future Air Traffic Management Concept Evaluation Tool (FACET) to global scale. This new capability is used to present results on the evolution of global air traffic patterns from a concentration of traffic inside US, Europe and across the Atlantic Ocean to a more diverse traffic pattern across the globe with accelerated growth in Asia, Australia, Africa and South America. The simulation analyzes seasonal variation in the long-haul wind-optimal traffic patterns in six major regions of the world and provides potential time-savings of wind-optimal routes compared with either great circle routes or current flight-plans if available.

  2. Spatial Copula Model for Imputing Traffic Flow Data from Remote Microwave Sensors.

    PubMed

    Ma, Xiaolei; Luan, Sen; Du, Bowen; Yu, Bin

    2017-09-21

    Issues of missing data have become increasingly serious with the rapid increase in usage of traffic sensors. Analyses of the Beijing ring expressway have showed that up to 50% of microwave sensors pose missing values. The imputation of missing traffic data must be urgently solved although a precise solution that cannot be easily achieved due to the significant number of missing portions. In this study, copula-based models are proposed for the spatial interpolation of traffic flow from remote traffic microwave sensors. Most existing interpolation methods only rely on covariance functions to depict spatial correlation and are unsuitable for coping with anomalies due to Gaussian consumption. Copula theory overcomes this issue and provides a connection between the correlation function and the marginal distribution function of traffic flow. To validate copula-based models, a comparison with three kriging methods is conducted. Results indicate that copula-based models outperform kriging methods, especially on roads with irregular traffic patterns. Copula-based models demonstrate significant potential to impute missing data in large-scale transportation networks.

  3. Realistic Data-Driven Traffic Flow Animation Using Texture Synthesis.

    PubMed

    Chao, Qianwen; Deng, Zhigang; Ren, Jiaping; Ye, Qianqian; Jin, Xiaogang

    2018-02-01

    We present a novel data-driven approach to populate virtual road networks with realistic traffic flows. Specifically, given a limited set of vehicle trajectories as the input samples, our approach first synthesizes a large set of vehicle trajectories. By taking the spatio-temporal information of traffic flows as a 2D texture, the generation of new traffic flows can be formulated as a texture synthesis process, which is solved by minimizing a newly developed traffic texture energy. The synthesized output captures the spatio-temporal dynamics of the input traffic flows, and the vehicle interactions in it strictly follow traffic rules. After that, we position the synthesized vehicle trajectory data to virtual road networks using a cage-based registration scheme, where a few traffic-specific constraints are enforced to maintain each vehicle's original spatial location and synchronize its motion in concert with its neighboring vehicles. Our approach is intuitive to control and scalable to the complexity of virtual road networks. We validated our approach through many experiments and paired comparison user studies.

  4. Air Traffic Sector Configuration Change Frequency

    NASA Technical Reports Server (NTRS)

    Chatterji, Gano B.; Drew, Michael

    2010-01-01

    A Mixed Integer Linear Programming method is used for creating sectors in Fort Worth, Cleveland, and Los Angeles centers based on several days of good-weather traffic data. The performance of these sectors is studied when they are subjected to traffic data from different days. Additionally, the advantage of using different sector designs at different times of day with varying traffic loads is examined. Specifically, traffic data from 10 days are used for design, and 47 other days are played back to test if the traffic-counts stay below the design values used in creating the partitions. The primary findings of this study are as follows. Sectors created with traffic from good-weather days can be used on other good-weather days. Sector configurations created with two hours of traffic can be used for 6 to 12 hours without exceeding the peak-count requirement. Compared to using a single configuration for the entire day, most of the sector-hour reduction is achieved by using two sector configurations -one during daytime hours and one during nighttime hours.

  5. Methodology for Generating Conflict Scenarios by Time Shifting Recorded Traffic Data

    NASA Technical Reports Server (NTRS)

    Paglione, Mike; Oaks, Robert; Bilimoria, Karl D.

    2003-01-01

    A methodology is presented for generating conflict scenarios that can be used as test cases to estimate the operational performance of a conflict probe. Recorded air traffic data is time shifted to create traffic scenarios featuring conflicts with characteristic properties similar to those encountered in typical air traffic operations. First, a reference set of conflicts is obtained from trajectories that are computed using birth points and nominal flight plans extracted from recorded traffic data. Distributions are obtained for several primary properties (e.g., encounter angle) that are most likely to affect the performance of a conflict probe. A genetic algorithm is then utilized to determine the values of time shifts for the recorded track data so that the primary properties of conflicts generated by the time shifted data match those of the reference set. This methodology is successfully demonstrated using recorded traffic data for the Memphis Air Route Traffic Control Center; a key result is that the required time shifts are less than 5 min for 99% of the tracks. It is also observed that close matching of the primary properties used in this study additionally provides a good match for some other secondary properties.

  6. Guide to long term pavement performance (LTPP) traffic data collection and processing

    DOT National Transportation Integrated Search

    2000-04-11

    The goal of this report is to document the process and procedures used by LTPP to collect and store the traffic data used to estimate pavement loadings. This first section of this report provides introductory material on the traffic data collection p...

  7. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to... reviewing all available traffic data, physical site data and air quality and meteorological data for all... containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air...

  8. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to... reviewing all available traffic data, physical site data and air quality and meteorological data for all... containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air...

  9. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to... reviewing all available traffic data, physical site data and air quality and meteorological data for all... containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air...

  10. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to... reviewing all available traffic data, physical site data and air quality and meteorological data for all... containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air...

  11. 40 CFR 52.1164 - Localized high concentrations-carbon monoxide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... meteorological modeling, traffic flow monitoring, air quality monitoring and other measures necessary to... reviewing all available traffic data, physical site data and air quality and meteorological data for all... containing measures to regulate traffic and parking so as to reduce carbon monoxide emissions to achieve air...

  12. Ohio traffic crash facts, 2000

    DOT National Transportation Integrated Search

    2001-08-06

    Information contained in this report represents traffic crash data and supporting information from the Ohio Integrated Traffic Records System for the calendar year of 2000. Data presented herein represents the crash report forms as submitted to the O...

  13. 2003 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2004-10-01

    The Crash Analysis and Reporting Unit compiles data for reported motor vehicle traffic crashes occurring on city streets, county roads and state highways. The data supports various local, county and state traffic safety programs, engineering and plan...

  14. Illinois travel statistics, 2009

    DOT National Transportation Integrated Search

    2010-01-01

    The 2009 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  15. Illinois travel statistics, 2001

    DOT National Transportation Integrated Search

    2002-01-01

    The 2001 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this : level of detail are within the Illinois Department of Transporta...

  16. Illinois travel statistics, 2003

    DOT National Transportation Integrated Search

    2004-01-01

    The 2003 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  17. Illinois travel statistics, 2010

    DOT National Transportation Integrated Search

    2011-01-01

    The 2010 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  18. Illinois travel statistics, 2005

    DOT National Transportation Integrated Search

    2006-01-01

    The 2005 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  19. Illinois travel statistics, 2007

    DOT National Transportation Integrated Search

    2008-01-01

    The 2007 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  20. Illinois travel statistics, 2000

    DOT National Transportation Integrated Search

    2001-01-01

    The 2000 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this : level of detail are within the Illinois Department of Transporta...

  1. Illinois travel statistics, 2006

    DOT National Transportation Integrated Search

    2007-01-01

    The 2006 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  2. Illinois travel statistics, 2002

    DOT National Transportation Integrated Search

    2003-01-01

    The 2002 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  3. Illinois travel statistics, 2008

    DOT National Transportation Integrated Search

    2009-01-01

    The 2008 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  4. Illinois travel statistics, 2004

    DOT National Transportation Integrated Search

    2005-01-01

    The 2004 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this level : of detail are within the Illinois Department of Transporta...

  5. Illinois travel statistics, 1999

    DOT National Transportation Integrated Search

    2000-01-01

    The 1999 Illinois Travel Statistics publication is assembled to provide detailed traffic : information to the different users of traffic data. While most users of traffic data at this : level of detail are within the Illinois Department of Transporta...

  6. Measurement of the length of pedestrian crossings and detection of traffic lights from image data

    NASA Astrophysics Data System (ADS)

    Shioyama, Tadayoshi; Wu, Haiyuan; Nakamura, Naoki; Kitawaki, Suguru

    2002-09-01

    This paper proposes a method for measurement of the length of a pedestrian crossing and for the detection of traffic lights from image data observed with a single camera. The length of a crossing is measured from image data of white lines painted on the road at a crossing by using projective geometry. Furthermore, the state of the traffic lights, green (go signal) or red (stop signal), is detected by extracting candidates for the traffic light region with colour similarity and selecting a true traffic light from them using affine moment invariants. From the experimental results, the length of a crossing is measured with an accuracy such that the maximum relative error of measured length is less than 5% and the rms error is 0.38 m. A traffic light is efficiently detected by selecting a true traffic light region with an affine moment invariant.

  7. Analysis of vehicular traffic flow in the major areas of Kuala Lumpur utilizing open-traffic

    NASA Astrophysics Data System (ADS)

    Manogaran, Saargunawathy; Ali, Muhammad; Yusof, Kamaludin Mohamad; Suhaili, Ramdhan

    2017-09-01

    Vehicular traffic congestion occurs when a large number of drivers are overcrowded on the road and the traffic flow does not run smoothly. Traffic congestion causes chaos on the road and interruption to daily activities of users. Time consumed on road give lots of negative effects on productivity, social behavior, environmental and cost to economy. Congestion is worsens and leads to havoc during the emergency such as flood, accidents, road maintenance and etc., where behavior of traffic flow is always unpredictable and uncontrollable. Real-time and historical traffic data are critical inputs for most traffic flow analysis applications. Researcher attempt to predict traffic using simulations as there is no exact model of traffic flow exists due to its high complexity. Open Traffic is an open source platform available for traffic data analysis linked to Open Street Map (OSM). This research is aimed to study and understand the Open Traffic platform. The real-time traffic flow pattern in Kuala Lumpur area was successfully been extracted and analyzed using Open Traffic. It was observed that the congestion occurs on every major road in Kuala Lumpur and most of it owes to the offices and the economic and commercial centers during rush hours. At some roads the congestion occurs at night due to the tourism activities.

  8. Modeling hurricane evacuation traffic : a mobile real-time traffic counter for monitoring hurricane evacuation traffic conditions.

    DOT National Transportation Integrated Search

    2006-04-01

    In this research report, an investigation was conducted to identify a suitable traffic monitoring device for collecting traffic data during actual emergency evacuation conditions that may result from hurricanes in Louisiana. The study reviewed thorou...

  9. 75 FR 20423 - Tenth Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ..., Airport Data Base) Briefing from SC-186/WG-51 (CPDLC support for Interval Management) Review of the work... 214: Working Group 78: Standards for Air Traffic Data Communication Services AGENCY: Federal Aviation... Traffic Data Communication Services. SUMMARY: The FAA is issuing this notice to advise the public of a...

  10. 2009 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2010-09-01

    The Crash Analysis and Reporting Unit compiles data and publishes statistics for reported motor vehicle : traffic crashes per ORS 802.050(2) and 802.220(6). The data supports various local, county and state : traffic safety programs, engineering and ...

  11. 2008 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2009-09-01

    The Crash Analysis and Reporting Unit compiles data and publishes statistics for reported motor vehicle : traffic crashes per ORS 802.050(2) and 802.220(6). The data supports various local, county and state : traffic safety programs, engineering and ...

  12. 2010 Oregon traffic crash summary

    DOT National Transportation Integrated Search

    2011-08-01

    The Crash Analysis and Reporting Unit compiles data and publishes statistics for reported motor vehicle : traffic crashes per ORS 802.050(2) and 802.220(6). The data supports various local, county and state : traffic safety programs, engineering and ...

  13. Querying and Extracting Timeline Information from Road Traffic Sensor Data

    PubMed Central

    Imawan, Ardi; Indikawati, Fitri Indra; Kwon, Joonho; Rao, Praveen

    2016-01-01

    The escalation of traffic congestion in urban cities has urged many countries to use intelligent transportation system (ITS) centers to collect historical traffic sensor data from multiple heterogeneous sources. By analyzing historical traffic data, we can obtain valuable insights into traffic behavior. Many existing applications have been proposed with limited analysis results because of the inability to cope with several types of analytical queries. In this paper, we propose the QET (querying and extracting timeline information) system—a novel analytical query processing method based on a timeline model for road traffic sensor data. To address query performance, we build a TQ-index (timeline query-index) that exploits spatio-temporal features of timeline modeling. We also propose an intuitive timeline visualization method to display congestion events obtained from specified query parameters. In addition, we demonstrate the benefit of our system through a performance evaluation using a Busan ITS dataset and a Seattle freeway dataset. PMID:27563900

  14. A Kriging based spatiotemporal approach for traffic volume data imputation

    PubMed Central

    Han, Lee D.; Liu, Xiaohan; Pu, Li; Chin, Shih-miao; Hwang, Ho-ling

    2018-01-01

    Along with the rapid development of Intelligent Transportation Systems, traffic data collection technologies have progressed fast. The emergence of innovative data collection technologies such as remote traffic microwave sensor, Bluetooth sensor, GPS-based floating car method, and automated license plate recognition, has significantly increased the variety and volume of traffic data. Despite the development of these technologies, the missing data issue is still a problem that poses great challenge for data based applications such as traffic forecasting, real-time incident detection, dynamic route guidance, and massive evacuation optimization. A thorough literature review suggests most current imputation models either focus on the temporal nature of the traffic data and fail to consider the spatial information of neighboring locations or assume the data follow a certain distribution. These two issues reduce the imputation accuracy and limit the use of the corresponding imputation methods respectively. As a result, this paper presents a Kriging based data imputation approach that is able to fully utilize the spatiotemporal correlation in the traffic data and that does not assume the data follow any distribution. A set of scenarios with different missing rates are used to evaluate the performance of the proposed method. The performance of the proposed method was compared with that of two other widely used methods, historical average and K-nearest neighborhood. Comparison results indicate that the proposed method has the highest imputation accuracy and is more flexible compared to other methods. PMID:29664928

  15. Exploring data sources for road traffic injury in Cameroon: Collection and completeness of police records, newspaper reports, and a hospital trauma registry.

    PubMed

    Juillard, Catherine; Kouo Ngamby, Marquise; Ekeke Monono, Martin; Etoundi Mballa, Georges Alain; Dicker, Rochelle A; Stevens, Kent A; Hyder, Adnan A

    2017-12-01

    Road traffic injury surveillance systems are a cornerstone of organized efforts at injury control. Although high-income countries rely on established trauma registries and police databases, in low- and middle-income countries, the data source that provides the best collection of road traffic injury events in specific low- and middle-income country contexts without mature surveillance systems is unclear. The objective of this study was to compare the information available on road traffic injuries in 3 data sources used for surveillance in the sub-Saharan African country of Cameroon, providing potential insight on data sources for road traffic injury surveillance in low- and middle-income countries. We assessed the number of events captured and the information available in Yaoundé, Cameroon, from 3 separate sources of data on road traffic injuries: trauma registry, police records, and newspapers. Data were collected from a single-hospital trauma registry, police records, and the 6 most widely circulated newspapers in Yaoundé during a 6-month period in 2009. The number of road traffic injury events, mortality, and other variables included commonly in injury surveillance systems were recorded. We compared these sources using descriptive analysis. Hospital, police, and newspaper sources recorded 1,686, 273, and 480 road traffic injuries, respectively. The trauma registry provided the most complete data for the majority of variables explored; however, the newspaper data source captured 2, mass casualty, train crash events unrecorded in the other sources. Police data provided the most complete information on first responders to the scene, missing in only 7%. Investing in the hospital-based trauma registry may yield the best surveillance for road traffic injuries in some low- and middle-income countries, such as Yaoundé, Cameroon; however, police and newspaper reports may serve as alternative data sources when specific information is needed. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. 1997 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    1998-06-01

    This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1997. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...

  17. 1995 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    1996-09-01

    This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1995. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...

  18. 2000 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2002-03-01

    This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2000. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...

  19. 2005 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2006-11-01

    This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2005. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...

  20. 2001 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2003-01-01

    This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2001. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...

  1. 2008 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2010-05-01

    This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through December, : 2008. It presents crash data in the form of graphs for those who : prefer an impressionistic view and tables for those wh...

  2. 1996 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    1997-06-01

    This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1997. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...

  3. 1998 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    1999-06-01

    This edition of New Mexico Traffic Crash Information reviews : traffic crash data in New Mexico from January through : December, 1998. It presents crash data in the form of graphs : for those who prefer an impressionistic view and tables for : those ...

  4. 2002 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2004-02-01

    This edition of New Mexico Traffic Crash Information reviews traffic : crash data in New Mexico from January through December, 2002. : It presents crash data in the form of graphs for those who prefer : an impressionistic view and tables for those wh...

  5. Evaluation of the traffic count program.

    DOT National Transportation Integrated Search

    1978-01-01

    The purpose of this study was to determine the Department's needs for traffic count data, to relate them to an evaluation of the traffic count programs and procedures, to identify problems and deficiencies with data requirements, and to seek means of...

  6. National Airspace System Delay Estimation Using Weather Weighted Traffic Counts

    NASA Technical Reports Server (NTRS)

    Chatterji, Gano B.; Sridhar, Banavar

    2004-01-01

    Assessment of National Airspace System performance, which is usually measured in terms of delays resulting from the application of traffic flow management initiatives in response to weather conditions, volume, equipment outages and runway conditions, is needed both for guiding flow control decisions during the day of operations and for post operations analysis. Comparison of the actual delay, resulting from the traffic flow management initiatives, with the expected delay, based on traffic demand and other conditions, provides the assessment of the National Airspace System performance. This paper provides a method for estimating delay using the expected traffic demand and weather. In order to identify the cause of delays, 517 days of National Airspace System delay data reported by the Federal Aviation Administration s Operations Network were analyzed. This analysis shows that weather is the most important causal factor for delays followed by equipment and runway delays. Guided by these results, the concept of weather weighted traffic counts as a measure of system delay is described. Examples are given to show the variation of these counts as a function of time of the day. The various datasets, consisting of aircraft position data, enroute severe weather data, surface wind speed and visibility data, reported delay data and number of aircraft handled by the Centers data, and their sources are described. The procedure for selecting reference days on which traffic was minimally impacted by weather is described. Different traffic demand on each reference day of the week, determined by analysis of 42 days of traffic and delay data, was used as the expected traffic demand for each day of the week. Next, the method for computing the weather weighted traffic counts using the expected traffic demand, derived from reference days, and the expanded regions around severe weather cells is discussed. It is shown via a numerical example that this approach improves the dynamic range of the weather weighted traffic counts considerably. Time histories of these new weather weighted traffic counts are used for synthesizing two statistical features, six histogram features and six time domain features. In addition to these enroute weather features, two surface weather features of number of major airports in the United States with high mean winds and low mean visibility are also described. A least squares procedure for establishing a functional relation between the features, using combinations of these features, and system delays is explored using 36 days of data. Best correlations between the estimated delays using the functional relation and the actual delays provided by the Operations Network are obtained with two different combinations of features: 1) six time domain features of weather weighted traffic counts plus two surface weather features, and 2) six histogram features and mean of weather weighted traffic counts along with the two surface weather features. Correlation coefficient values of 0.73 and 0.83 were found in these two instances.

  7. Assimilating Eulerian and Lagrangian data in traffic-flow models

    NASA Astrophysics Data System (ADS)

    Xia, Chao; Cochrane, Courtney; DeGuire, Joseph; Fan, Gaoyang; Holmes, Emma; McGuirl, Melissa; Murphy, Patrick; Palmer, Jenna; Carter, Paul; Slivinski, Laura; Sandstede, Björn

    2017-05-01

    Data assimilation of traffic flow remains a challenging problem. One difficulty is that data come from different sources ranging from stationary sensors and camera data to GPS and cell phone data from moving cars. Sensors and cameras give information about traffic density, while GPS data provide information about the positions and velocities of individual cars. Previous methods for assimilating Lagrangian data collected from individual cars relied on specific properties of the underlying computational model or its reformulation in Lagrangian coordinates. These approaches make it hard to assimilate both Eulerian density and Lagrangian positional data simultaneously. In this paper, we propose an alternative approach that allows us to assimilate both Eulerian and Lagrangian data. We show that the proposed algorithm is accurate and works well in different traffic scenarios and regardless of whether ensemble Kalman or particle filters are used. We also show that the algorithm is capable of estimating parameters and assimilating real traffic observations and synthetic observations obtained from microscopic models.

  8. 14 CFR Section 25 - Traffic and Capacity Elements

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Traffic and Capacity Elements Section 25... Traffic Reporting Requirements Section 25 Traffic and Capacity Elements General Instructions. (a) All prescribed reporting for traffic and capacity elements shall conform with the data compilation standards set...

  9. 14 CFR Section 25 - Traffic and Capacity Elements

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Traffic and Capacity Elements Section 25... Traffic Reporting Requirements Section 25 Traffic and Capacity Elements General Instructions. (a) All prescribed reporting for traffic and capacity elements shall conform with the data compilation standards set...

  10. 76 FR 58078 - Thirteenth Meeting: RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-19

    ... Committee 214: Working Group 78: Standards for Air Traffic Data Communication Services AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 214: Working Group 78... public of a meeting of the RTCA Special Committee 214: Working Group 78: Standards for Air Traffic Data...

  11. Virtualized Traffic: reconstructing traffic flows from discrete spatiotemporal data.

    PubMed

    Sewall, Jason; van den Berg, Jur; Lin, Ming C; Manocha, Dinesh

    2011-01-01

    We present a novel concept, Virtualized Traffic, to reconstruct and visualize continuous traffic flows from discrete spatiotemporal data provided by traffic sensors or generated artificially to enhance a sense of immersion in a dynamic virtual world. Given the positions of each car at two recorded locations on a highway and the corresponding time instances, our approach can reconstruct the traffic flows (i.e., the dynamic motions of multiple cars over time) between the two locations along the highway for immersive visualization of virtual cities or other environments. Our algorithm is applicable to high-density traffic on highways with an arbitrary number of lanes and takes into account the geometric, kinematic, and dynamic constraints on the cars. Our method reconstructs the car motion that automatically minimizes the number of lane changes, respects safety distance to other cars, and computes the acceleration necessary to obtain a smooth traffic flow subject to the given constraints. Furthermore, our framework can process a continuous stream of input data in real time, enabling the users to view virtualized traffic events in a virtual world as they occur. We demonstrate our reconstruction technique with both synthetic and real-world input. © 2011 IEEE Published by the IEEE Computer Society

  12. Spatial Copula Model for Imputing Traffic Flow Data from Remote Microwave Sensors

    PubMed Central

    Ma, Xiaolei; Du, Bowen; Yu, Bin

    2017-01-01

    Issues of missing data have become increasingly serious with the rapid increase in usage of traffic sensors. Analyses of the Beijing ring expressway have showed that up to 50% of microwave sensors pose missing values. The imputation of missing traffic data must be urgently solved although a precise solution that cannot be easily achieved due to the significant number of missing portions. In this study, copula-based models are proposed for the spatial interpolation of traffic flow from remote traffic microwave sensors. Most existing interpolation methods only rely on covariance functions to depict spatial correlation and are unsuitable for coping with anomalies due to Gaussian consumption. Copula theory overcomes this issue and provides a connection between the correlation function and the marginal distribution function of traffic flow. To validate copula-based models, a comparison with three kriging methods is conducted. Results indicate that copula-based models outperform kriging methods, especially on roads with irregular traffic patterns. Copula-based models demonstrate significant potential to impute missing data in large-scale transportation networks. PMID:28934164

  13. 2009 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2011-05-01

    This edition of New Mexico Traffic Crash Information reviews traffic crash data in New Mexico from January through December, 2009. It presents crash data in the form of graphs for those who prefer an impressionistic view and tables for those who requ...

  14. 1999 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2001-03-01

    This edition of New Mexico Traffic Crash Information reviews traffic crash data in New MExico from January through Decemeber, 1999. It presents crash data in the form of graphs for those who prefer an impressionistic view and tables for those who req...

  15. Traffic safety facts 1995 : state traffic data

    DOT National Transportation Integrated Search

    1996-01-01

    Nationwide in 1993, traffic fatalities were up 2 percent. These tables provide summary data of fatal crashes for the United States and individually for the 50 states, the District of Columbia, and Puerto Rico (not included in the national totals). Th...

  16. A Wavelet Neural Network Optimal Control Model for Traffic-Flow Prediction in Intelligent Transport Systems

    NASA Astrophysics Data System (ADS)

    Huang, Darong; Bai, Xing-Rong

    Based on wavelet transform and neural network theory, a traffic-flow prediction model, which was used in optimal control of Intelligent Traffic system, is constructed. First of all, we have extracted the scale coefficient and wavelet coefficient from the online measured raw data of traffic flow via wavelet transform; Secondly, an Artificial Neural Network model of Traffic-flow Prediction was constructed and trained using the coefficient sequences as inputs and raw data as outputs; Simultaneous, we have designed the running principium of the optimal control system of traffic-flow Forecasting model, the network topological structure and the data transmitted model; Finally, a simulated example has shown that the technique is effectively and exactly. The theoretical results indicated that the wavelet neural network prediction model and algorithms have a broad prospect for practical application.

  17. Modeling level-of-safety for bus stops in China.

    PubMed

    Ye, Zhirui; Wang, Chao; Yu, Yongbo; Shi, Xiaomeng; Wang, Wei

    2016-08-17

    Safety performance at bus stops is generally evaluated by using historical traffic crash data or traffic conflict data. However, in China, it is quite difficult to obtain such data mainly due to the lack of traffic data management and organizational issues. In light of this, the primary objective of this study is to develop a quantitative approach to evaluate bus stop safety performance. The concept of level-of-safety for bus stops is introduced and corresponding models are proposed to quantify safety levels, which consider conflict points, traffic factors, geometric characteristics, traffic signs and markings, pavement conditions, and lighting conditions. Principal component analysis and k-means clustering methods were used to model and quantify safety levels for bus stops. A case study was conducted to show the applicability of the proposed model with data collected from 46 samples for the 7 most common types of bus stops in China, using 32 of the samples for modeling and 14 samples for illustration. Based on the case study, 6 levels of safety for bus stops were defined. Finally, a linear regression analysis between safety levels and the number of traffic conflicts showed that they had a strong relationship (R(2) value of 0.908). The results indicated that the method was well validated and could be practically used for the analysis and evaluation of bus stop safety in China. The proposed model was relatively easy to implement without the requirement of traffic crash data and/or traffic conflict data. In addition, with the proposed method, it was feasible to evaluate countermeasures to improve bus stop safety (e.g., exclusive bus lanes).

  18. enviroCar - citizen science for sustainable traffic

    NASA Astrophysics Data System (ADS)

    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-temporal analyses by themselves. Thus, the platform also provides a means to analyze issues, such as repeated stops at a particular traffic light, and to communicate the results to other stakeholders, e.g. traffic planners or politicians. For traffic planners, the enviroCar project can also serve as a valuable additional data source for evaluating certain decisions, e.g. changing traffic light sequences. As not only the pure GPS data but also the car sensor data is collected, enviroCar enables to directly relate the traffic data to environmental parameters such as air pollutant emissions and thus to identify, for example, hotspots of CO2 emissions in a street network. Current research activities comprise technical issues, such as implementing scalable solutions for visualizing and analyzing big data sets, on improving estimation methods for fuel consumption and air pollutant emissions, but also include the development of novel spatio-temporal analysis and visualization methods and novel incentives for participation in crowd-sourcing and analyzing geospatial information.

  19. Advanced Traffic Management Systems (ATMS) research analysis database system

    DOT National Transportation Integrated Search

    2001-06-01

    The ATMS Research Analysis Database Systems (ARADS) consists of a Traffic Software Data Dictionary (TSDD) and a Traffic Software Object Model (TSOM) for application to microscopic traffic simulation and signal optimization domains. The purpose of thi...

  20. Spatiotemporal Context Awareness for Urban Traffic Modeling and Prediction: Sparse Representation Based Variable Selection.

    PubMed

    Yang, Su; Shi, Shixiong; Hu, Xiaobing; Wang, Minjie

    2015-01-01

    Spatial-temporal correlations among the data play an important role in traffic flow prediction. Correspondingly, traffic modeling and prediction based on big data analytics emerges due to the city-scale interactions among traffic flows. A new methodology based on sparse representation is proposed to reveal the spatial-temporal dependencies among traffic flows so as to simplify the correlations among traffic data for the prediction task at a given sensor. Three important findings are observed in the experiments: (1) Only traffic flows immediately prior to the present time affect the formation of current traffic flows, which implies the possibility to reduce the traditional high-order predictors into an 1-order model. (2) The spatial context relevant to a given prediction task is more complex than what is assumed to exist locally and can spread out to the whole city. (3) The spatial context varies with the target sensor undergoing prediction and enlarges with the increment of time lag for prediction. Because the scope of human mobility is subject to travel time, identifying the varying spatial context against time lag is crucial for prediction. Since sparse representation can capture the varying spatial context to adapt to the prediction task, it outperforms the traditional methods the inputs of which are confined as the data from a fixed number of nearby sensors. As the spatial-temporal context for any prediction task is fully detected from the traffic data in an automated manner, where no additional information regarding network topology is needed, it has good scalability to be applicable to large-scale networks.

  1. Spatiotemporal Context Awareness for Urban Traffic Modeling and Prediction: Sparse Representation Based Variable Selection

    PubMed Central

    Yang, Su; Shi, Shixiong; Hu, Xiaobing; Wang, Minjie

    2015-01-01

    Spatial-temporal correlations among the data play an important role in traffic flow prediction. Correspondingly, traffic modeling and prediction based on big data analytics emerges due to the city-scale interactions among traffic flows. A new methodology based on sparse representation is proposed to reveal the spatial-temporal dependencies among traffic flows so as to simplify the correlations among traffic data for the prediction task at a given sensor. Three important findings are observed in the experiments: (1) Only traffic flows immediately prior to the present time affect the formation of current traffic flows, which implies the possibility to reduce the traditional high-order predictors into an 1-order model. (2) The spatial context relevant to a given prediction task is more complex than what is assumed to exist locally and can spread out to the whole city. (3) The spatial context varies with the target sensor undergoing prediction and enlarges with the increment of time lag for prediction. Because the scope of human mobility is subject to travel time, identifying the varying spatial context against time lag is crucial for prediction. Since sparse representation can capture the varying spatial context to adapt to the prediction task, it outperforms the traditional methods the inputs of which are confined as the data from a fixed number of nearby sensors. As the spatial-temporal context for any prediction task is fully detected from the traffic data in an automated manner, where no additional information regarding network topology is needed, it has good scalability to be applicable to large-scale networks. PMID:26496370

  2. Problems in air traffic management. I., Longitudinal prediction of effectiveness of air traffic controllers.

    DOT National Transportation Integrated Search

    1961-12-01

    Current (1961) job performance evaluations and medical history data were obtained for 149 of 197 men trained in air traffic control work in 1956. Evaluations of psychological test and biographical data collected at the time they went through training...

  3. Magnetic-Based NDE of Prestressed and Post-Tensioned Concrete Members: The MFL System.

    DOT National Transportation Integrated Search

    1997-07-01

    Many metropolitan areas have begun or are planning to implement traffic monitoring programs to meet the many demands for traffic data. The purpose of this project is to document a series of examples of urban traffic monitoring data collection program...

  4. 2006 continuous traffic count data and traffic characteristics on Nebraska streets and highways

    DOT National Transportation Integrated Search

    2007-05-01

    The Nebraska Department of Roads, in cooperation with the Federal Highway Administration, : collected and analyzed data at 61 continuous traffic count locations in 2006. Of these 61 locations, 38 : are on rural state and federal highways, 8 on low vo...

  5. 2009 continuous traffic count data and traffic characteristics on Nebraska streets and highways

    DOT National Transportation Integrated Search

    2010-04-01

    The Nebraska Department of Roads, in cooperation with the Federal Highway Administration, collected and analyzed data at 61 continuous traffic count locations in 2009. Of these 61 locations, 38 are on rural state and federal highways, 8 on low volume...

  6. 2004 continuous traffic count data and traffic characteristics on Nebraska streets and highways

    DOT National Transportation Integrated Search

    2005-05-01

    The Nebraska Department of Roads, in cooperation with the Federal Highway Administration, : collected and analyzed data at 63 continuous traffic count locations in 2004. Of these 61 locations, 39 : are on rural state and federal highways, 8 on low vo...

  7. 77 FR 49859 - Proposed Traffic Records Program Assessment Advisory

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ... States on the collection, management, and analysis of data used to inform highway and traffic safety... prioritize traffic safety issues and to choose appropriate countermeasures and evaluate their effectiveness. This document provides information on the contents, capabilities, and data quality attributes of an...

  8. Data traffic reduction schemes for Cholesky factorization on asynchronous multiprocessor systems

    NASA Technical Reports Server (NTRS)

    Naik, Vijay K.; Patrick, Merrell L.

    1989-01-01

    Communication requirements of Cholesky factorization of dense and sparse symmetric, positive definite matrices are analyzed. The communication requirement is characterized by the data traffic generated on multiprocessor systems with local and shared memory. Lower bound proofs are given to show that when the load is uniformly distributed the data traffic associated with factoring an n x n dense matrix using n to the alpha power (alpha less than or equal 2) processors is omega(n to the 2 + alpha/2 power). For n x n sparse matrices representing a square root of n x square root of n regular grid graph the data traffic is shown to be omega(n to the 1 + alpha/2 power), alpha less than or equal 1. Partitioning schemes that are variations of block assignment scheme are described and it is shown that the data traffic generated by these schemes are asymptotically optimal. The schemes allow efficient use of up to O(n to the 2nd power) processors in the dense case and up to O(n) processors in the sparse case before the total data traffic reaches the maximum value of O(n to the 3rd power) and O(n to the 3/2 power), respectively. It is shown that the block based partitioning schemes allow a better utilization of the data accessed from shared memory and thus reduce the data traffic than those based on column-wise wrap around assignment schemes.

  9. A generic approach for examining the effectiveness of traffic control devices in school zones.

    PubMed

    Zhao, Xiaohua; Li, Jiahui; Ding, Han; Zhang, Guohui; Rong, Jian

    2015-09-01

    The effectiveness and performance of traffic control devices in school zones have been impacted significantly by many factors, such as driver behavioral attributes, roadway geometric features, environmental characteristics, weather and visibility conditions, region-wide traffic regulations and policies, control modes, etc. When deploying traffic control devices in school zones, efforts are needed to clarify: (1) whether traffic control device installation is warranted; and (2) whether other device effectively complements this traffic control device and strengthens its effectiveness. In this study, a generic approach is developed to examine and evaluate the effectiveness of various traffic control devices deployed in school zones through driving simulator-based experiments. A Traffic Control Device Selection Model (TCDSM) is developed and two representative school zones are selected as the testbed in Beijing for driving simulation implementation to enhance its applicability. Statistical analyses are conducted to extract the knowledge from test data recorded by a driving simulator. Multiple measures of effectiveness (MOEs) are developed and adopted including average speed, relative speed difference, and standard deviation of acceleration for traffic control device performance quantification. The experimental tests and analysis results reveal that the appropriateness of the installation of certain traffic control devices can be statistically verified by TCDSM. The proposed approach provides a generic framework to assess traffic control device performance in school zones including experiment design, statistical formulation, data analysis, simulation model implementation, data interpretation, and recommendation development. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Wyoming Low-Volume Roads Traffic Volume Estimation

    DOT National Transportation Integrated Search

    2015-10-01

    Low-volume roads are excluded from regular traffic counts except on a need to know basis. But needs for traffic volume data on low-volume roads in road infrastructure management, safety, and air quality analysis have necessitated regular traffic volu...

  11. State of Kansas traffic records assessment : March 21-25, 2005

    DOT National Transportation Integrated Search

    2005-01-01

    The scope of this traffic records assessment included all of the data systems comprising a traffic records system. The purpose of this assessment is to determine whether Kansass traffic records system is capable of supporting managements needs ...

  12. Transportation data requirements : evaluation of portable traffic recorders.

    DOT National Transportation Integrated Search

    1978-01-01

    The objective of this study was to evaluate the accuracy of the Department's portable traffic recorder models under diverse types of traffic conditions. The study was conducted by (1) reviewing the characteristics of five models of traffic recorders,...

  13. Development and application of traffic flow information collecting and analysis system based on multi-type video

    NASA Astrophysics Data System (ADS)

    Lu, Mujie; Shang, Wenjie; Ji, Xinkai; Hua, Mingzhuang; Cheng, Kuo

    2015-12-01

    Nowadays, intelligent transportation system (ITS) has already become the new direction of transportation development. Traffic data, as a fundamental part of intelligent transportation system, is having a more and more crucial status. In recent years, video observation technology has been widely used in the field of traffic information collecting. Traffic flow information contained in video data has many advantages which is comprehensive and can be stored for a long time, but there are still many problems, such as low precision and high cost in the process of collecting information. This paper aiming at these problems, proposes a kind of traffic target detection method with broad applicability. Based on three different ways of getting video data, such as aerial photography, fixed camera and handheld camera, we develop a kind of intelligent analysis software which can be used to extract the macroscopic, microscopic traffic flow information in the video, and the information can be used for traffic analysis and transportation planning. For road intersections, the system uses frame difference method to extract traffic information, for freeway sections, the system uses optical flow method to track the vehicles. The system was applied in Nanjing, Jiangsu province, and the application shows that the system for extracting different types of traffic flow information has a high accuracy, it can meet the needs of traffic engineering observations and has a good application prospect.

  14. Entropy-based heavy tailed distribution transformation and visual analytics for monitoring massive network traffic

    NASA Astrophysics Data System (ADS)

    Han, Keesook J.; Hodge, Matthew; Ross, Virginia W.

    2011-06-01

    For monitoring network traffic, there is an enormous cost in collecting, storing, and analyzing network traffic datasets. Data mining based network traffic analysis has a growing interest in the cyber security community, but is computationally expensive for finding correlations between attributes in massive network traffic datasets. To lower the cost and reduce computational complexity, it is desirable to perform feasible statistical processing on effective reduced datasets instead of on the original full datasets. Because of the dynamic behavior of network traffic, traffic traces exhibit mixtures of heavy tailed statistical distributions or overdispersion. Heavy tailed network traffic characterization and visualization are important and essential tasks to measure network performance for the Quality of Services. However, heavy tailed distributions are limited in their ability to characterize real-time network traffic due to the difficulty of parameter estimation. The Entropy-Based Heavy Tailed Distribution Transformation (EHTDT) was developed to convert the heavy tailed distribution into a transformed distribution to find the linear approximation. The EHTDT linearization has the advantage of being amenable to characterize and aggregate overdispersion of network traffic in realtime. Results of applying the EHTDT for innovative visual analytics to real network traffic data are presented.

  15. Design and Operational Evaluation of the Traffic Management Advisor at the Ft. Worth Air Route Traffic Control Center

    NASA Technical Reports Server (NTRS)

    Swenson, Harry N.; Vincent, Danny; Tobias, Leonard (Technical Monitor)

    1997-01-01

    NASA and the FAA have designed and developed and an automation tool known as the Traffic Management Advisor (TMA). The system was operationally evaluated at the Ft. Worth Air Route Traffic Control Center (ARTCC). The TMA is a time-based strategic planning tool that provides Traffic Management Coordinators and En Route Air Traffic Controllers the ability to efficiently optimize the capacity of a demand impacted airport. The TMA consists of trajectory prediction, constraint-based runway scheduling, traffic flow visualization and controllers advisories. The TMA was used and operationally evaluated for forty-one rush traffic periods during a one month period in the Summer of 1996. The evaluations included all shifts of air traffic operations as well as periods of inclement weather. Performance data was collected for engineering and human factor analysis and compared with similar operations without the TMA. The engineering data indicates that the operations with the TMA show a one to two minute per aircraft delay reduction during rush periods. The human factor data indicate a perceived reduction in en route controller workload as well as an increase in job satisfaction. Upon completion of the evaluation, the TMA has become part of the normal operations at the Ft. Worth ARTCC.

  16. Stationary LiDAR for traffic and safety applications - vehicles interpretation and tracking.

    DOT National Transportation Integrated Search

    2014-01-01

    The goal of the T-Scan project is to develop a data processing module for a novel LiDAR-based traffic scanner to collect highly accurate microscopic traffic data at road intersections. : T-Scan uses Light Detection and Ranging (LiDAR) technology that...

  17. A hierarchical clustering scheme approach to assessment of IP-network traffic using detrended fluctuation analysis

    NASA Astrophysics Data System (ADS)

    Takuma, Takehisa; Masugi, Masao

    2009-03-01

    This paper presents an approach to the assessment of IP-network traffic in terms of the time variation of self-similarity. To get a comprehensive view in analyzing the degree of long-range dependence (LRD) of IP-network traffic, we use a hierarchical clustering scheme, which provides a way to classify high-dimensional data with a tree-like structure. Also, in the LRD-based analysis, we employ detrended fluctuation analysis (DFA), which is applicable to the analysis of long-range power-law correlations or LRD in non-stationary time-series signals. Based on sequential measurements of IP-network traffic at two locations, this paper derives corresponding values for the LRD-related parameter α that reflects the degree of LRD of measured data. In performing the hierarchical clustering scheme, we use three parameters: the α value, average throughput, and the proportion of network traffic that exceeds 80% of network bandwidth for each measured data set. We visually confirm that the traffic data can be classified in accordance with the network traffic properties, resulting in that the combined depiction of the LRD and other factors can give us an effective assessment of network conditions at different times.

  18. Traffic safety measures using multiple streams real time data : final report

    DOT National Transportation Integrated Search

    2017-01-04

    Traffic crashes and accidents result from many complex factors, but at a basic level, they are conflicts : among vehicles and/or other road users. Roadway conditions, traffic signals, weather, traffic flow, : drivers' behavior and health of vehicles ...

  19. Virtual Induction Loops Based on Cooperative Vehicular Communications

    PubMed Central

    Gramaglia, Marco; Bernardos, Carlos J.; Calderon, Maria

    2013-01-01

    Induction loop detectors have become the most utilized sensors in traffic management systems. The gathered traffic data is used to improve traffic efficiency (i.e., warning users about congested areas or planning new infrastructures). Despite their usefulness, their deployment and maintenance costs are expensive. Vehicular networks are an emerging technology that can support novel strategies for ubiquitous and more cost-effective traffic data gathering. In this article, we propose and evaluate VIL (Virtual Induction Loop), a simple and lightweight traffic monitoring system based on cooperative vehicular communications. The proposed solution has been experimentally evaluated through simulation using real vehicular traces. PMID:23348033

  20. [Definition of hospital discharge, serious injury and death from traffic injuries].

    PubMed

    Pérez, Katherine; Seguí-Gómez, María; Arrufat, Vita; Barberia, Eneko; Cabeza, Elena; Cirera, Eva; Gil, Mercedes; Martín, Carlos; Novoa, Ana M; Olabarría, Marta; Lardelli, Pablo; Suelves, Josep Maria; Santamariña-Rubio, Elena

    2014-01-01

    Road traffic injury surveillance involves methodological difficulties due, among other reasons, to the lack of consensus criteria for case definition. Police records have usually been the main source of information for monitoring traffic injuries, while health system data has hardly been used. Police records usually include comprehensive information on the characteristics of the crash, but often underreport injury cases and do not collect reliable information on the severity of injuries. However, statistics on severe traffic injuries have been based almost exclusively on police data. The aim of this paper is to propose criteria based on medical records to define: a) "Hospital discharge for traffic injuries", b) "Person with severe traffic injury", and c) "Death from traffic injuries" in order to homogenize the use of these sources. Copyright © 2014. Published by Elsevier Espana.

  1. 47 CFR 32.6532 - Network administration expense.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... includes such activities as controlling traffic flow, administering traffic measuring and monitoring devices, assigning equipment and load balancing, collecting and summarizing traffic data, administering...

  2. 47 CFR 32.6532 - Network administration expense.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... includes such activities as controlling traffic flow, administering traffic measuring and monitoring devices, assigning equipment and load balancing, collecting and summarizing traffic data, administering...

  3. 47 CFR 32.6532 - Network administration expense.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... includes such activities as controlling traffic flow, administering traffic measuring and monitoring devices, assigning equipment and load balancing, collecting and summarizing traffic data, administering...

  4. 78 FR 26847 - Including Specific Pavement Types in Federal-aid Highway Traffic Noise Analyses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ... traffic noise analyses. Current highway traffic noise analyses rely on data from three pavement types: dense-graded asphaltic concrete (DGAC), open-graded asphaltic concrete (OGAC), and Portland cement... noise analyses provide data for decisionmakers to make informed decisions on project alternatives and...

  5. Traffic safety facts 1997 : a compilation of motor vehicle crash data from the fatality analysis reporting system and the general estimates system

    DOT National Transportation Integrated Search

    1998-11-01

    In this annual report, Traffic Safety Facts 1997: A Compilation of Motor Vehicle Crash Data from the Fatality Analysis Reporting System and the General Estimates System, the National Highway Traffic Safety Administration (NHTSA) presents descriptive ...

  6. Evaluation of Traffic Information and Prediction System (TIPS) as work zone traffic control.

    DOT National Transportation Integrated Search

    2004-03-01

    As part of a pavement rehabilitation project on I-64, the Traffic Information and Prediction System (TIPS) was installed as a a means of providing real-time data for motorists in advance and through the work zone. This system collects real-time data ...

  7. Traffic safety facts 2007 : a compilation of motor vehicle crash data from the fatality analysis reporting system and the general estimates system

    DOT National Transportation Integrated Search

    2007-01-01

    In this annual report, Traffic Safety Facts 2007: A Compilation of Motor Vehicle Crash Data from the Fatality : Analysis Reporting System and the General Estimates System, the National Highway Traffic Safety Administration : (NHTSA) presents descript...

  8. Study of annoyance due to urban automobile traffic. Annex 4: A catalog of the characteristics of noise at different measuring points

    NASA Technical Reports Server (NTRS)

    Aubree, D.; Auzou, S.; Rapin, J. M.

    1984-01-01

    The characteristics of urban traffic were studied. Data synthesis of and data specifically for the city of Paris concerning noise due to automobile traffic were examined. Information on noise characteristics at different measuring locations is presented.

  9. Traffic safety facts 2008 : a compilation of motor vehicle crash data from the fatality analysis reporting system and the general estimates system

    DOT National Transportation Integrated Search

    2008-01-01

    In this annual report, Traffic Safety Facts 2008: A Compilation of Motor Vehicle Crash Data from the Fatality Analysis Reporting System and the General Estimates System, the National Highway Traffic Safety Administration (NHTSA) presents descriptive ...

  10. Traffic safety facts 2009 : a compilation of motor vehicle crash data from the fatality analysis reporting system and the general estimates system

    DOT National Transportation Integrated Search

    2009-01-01

    In this annual report, Traffic Safety Facts 2009: A Compilation of Motor Vehicle Crash Data from the Fatality Analysis Reporting System and the General Estimates System, the National Highway Traffic Safety Administration (NHTSA) presents descriptive ...

  11. The role of local urban traffic and meteorological conditions in air pollution: A data-based case study in Madrid, Spain

    NASA Astrophysics Data System (ADS)

    Laña, Ibai; Del Ser, Javier; Padró, Ales; Vélez, Manuel; Casanova-Mateo, Carlos

    2016-11-01

    Urban air pollution is a matter of growing concern for both public administrations and citizens. Road traffic is one of the main sources of air pollutants, though topography characteristics and meteorological conditions can make pollution levels increase or diminish dramatically. In this context an upsurge of research has been conducted towards functionally linking variables of such domains to measured pollution data, with studies dealing with up to one-hour resolution meteorological data. However, the majority of such reported contributions do not deal with traffic data or, at most, simulate traffic conditions jointly with the consideration of different topographical features. The aim of this study is to further explore this relationship by using high-resolution real traffic data. This paper describes a methodology based on the construction of regression models to predict levels of different pollutants (i.e. CO, NO, NO2, O3 and PM10) based on traffic data and meteorological conditions, from which an estimation of the predictive relevance (importance) of each utilized feature can be estimated by virtue of their particular training procedure. The study was made with one hour resolution meteorological, traffic and pollution historic data in roadside and background locations of the city of Madrid (Spain) captured over 2015. The obtained results reveal that the impact of vehicular emissions on the pollution levels is overshadowed by the effects of stable meteorological conditions of this city.

  12. MMPP Traffic Generator for the Testing of the SCAR 2 Fast Packet Switch

    NASA Technical Reports Server (NTRS)

    Chren, William A., Jr.

    1995-01-01

    A prototype MWP Traffic Generator (TG) has been designed for testing of the COMSAT-supplied SCAR II Fast Packet Switch. By generating packets distributed according to a Markov-Modulated Poisson Process (MMPP) model. it allows the assessment of the switch performance under traffic conditions that are more realistic than could be generated using the COMSAT-supplied Traffic Generator Module. The MMPP model is widely believed to model accurately real-world superimposed voice and data communications traffic. The TG was designed to be as much as possible of a "drop-in" replacement for the COMSAT Traffic Generator Module. The latter fit on two Altera EPM7256EGC 192-pin CPLDs and produced traffic for one switch input port. No board changes are necessary because it has been partitioned to use the existing board traces. The TG, consisting of parts "TGDATPROC" and "TGRAMCTL" must merely be reprogrammed into the Altera devices of the same name. However, the 040 controller software must be modified to provide TG initialization data. This data will be given in Section II.

  13. Predicting Information Flows in Network Traffic.

    ERIC Educational Resources Information Center

    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)

  14. Application of GPS Technology to Monitor Traffic Intensity and Soil Impacts in a Forest Harvest Operation

    Treesearch

    Emily A. Carter; Timothy P. McDonald; John L. Torbert

    1999-01-01

    A study was initiated in the Winter of 1998 to examine the utility of employing Global Positioning Systems (GPS) to monitor harvest traffic throughout a loblolly pine plantation and utilize traffic intensity information to assess impacts of select soil physical properties. Traffic maps prepared from GPS positional data indicated the highest concentration of traffic...

  15. Integrating internet GPS vehicle tracking data into a bottom-up vehicular emissions inventory and atmospheric simulation in South-East, Brazil

    NASA Astrophysics Data System (ADS)

    Ibarra Espinosa, S.; Ynoue, R.; Giannotti, M., , Dr

    2017-12-01

    It has been shown the importance of emissions inventories for air quality studies and environmental planning at local, regional (REAS), hemispheric (CLRTAP) and global (IPCC) scales. It has been shown also that vehicules are becoming the most important sources in urban centers. Several efforts has been made in order to model vehicular emissions to obtain more accurate emission factors based on Vehicular Specific Power (VPS) with IVE and MOVES based on VSP, MOBILE, VERSIT and COPERT based on average speed, or ARTEMIS and HBEFA based on traffic situations. However, little effort has been made to improve traffic activity data. In this study we are proposing using a novel approach to develop vehicular emissions inventory including point data from MAPLINK a company that feeds with traffic data to Google. This includes working and transforming massive amount of data to generate traffic flow and speeds. The region of study is the south east of Brazil including São Paulo metropolitan areas. To estimate vehicular emissions we are using the open source model VEIN available at https://CRAN.R-project.org/package=vein. We generated hourly traffic between 2010-04-21 and 2010-10-22, totalizing 145 hours. This data consists GPS readings from vehicles with assurance policy, applications and other sources. This type data presents spacial bias meaning that only a part of the vehicles are tracked. We corrected this bias using the calculated speed as proxy of traffic flow using measurements of traffic flow and speed per lane made in São Paulo. Then we calibrated the total traffic estimating Fuel Consumption with VEIN and comparing Fuel Sales for the region. We estimated the hourly vehicular emissions and produced emission maps and data-bases. In addition, we simulated atmospheric simulations using WRF-Chem to identify which inventory produces better agreement with air pollutant observations. New technologies and big data provides opportunities to improve vehicular emissions inventories.

  16. Predicting residential indoor concentrations of nitrogen dioxide, fine particulate matter, and elemental carbon using questionnaire and geographic information system based data

    NASA Astrophysics Data System (ADS)

    Baxter, Lisa K.; Clougherty, Jane E.; Paciorek, Christopher J.; Wright, Rosalind J.; Levy, Jonathan I.

    Previous studies have identified associations between traffic-related air pollution and adverse health effects. Most have used measurements from a few central ambient monitors and/or some measure of traffic as indicators of exposure, disregarding spatial variability and factors influencing personal exposure-ambient concentration relationships. This study seeks to utilize publicly available data (i.e., central site monitors, geographic information system, and property assessment data) and questionnaire responses to predict residential indoor concentrations of traffic-related air pollutants for lower socioeconomic status (SES) urban households. As part of a prospective birth cohort study in urban Boston, we collected indoor and outdoor 3-4 day samples of nitrogen dioxide (NO 2) and fine particulate matter (PM 2.5) in 43 low SES residences across multiple seasons from 2003 to 2005. Elemental carbon (EC) concentrations were determined via reflectance analysis. Multiple traffic indicators were derived using Massachusetts Highway Department data and traffic counts collected outside sampling homes. Home characteristics and occupant behaviors were collected via a standardized questionnaire. Additional housing information was collected through property tax records, and ambient concentrations were collected from a centrally located ambient monitor. The contributions of ambient concentrations, local traffic and indoor sources to indoor concentrations were quantified with regression analyses. PM 2.5 was influenced less by local traffic but had significant indoor sources, while EC was associated with traffic and NO 2 with both traffic and indoor sources. Comparing models based on covariate selection using p-values or a Bayesian approach yielded similar results, with traffic density within a 50 m buffer of a home and distance from a truck route as important contributors to indoor levels of NO 2 and EC, respectively. The Bayesian approach also highlighted the uncertanity in the models. We conclude that by utilizing public databases and focused questionnaire data we can identify important predictors of indoor concentrations for multiple air pollutants in a high-risk population.

  17. The Loss of Efficiency Caused by Agents’ Uncoordinated Routing in Transport Networks

    PubMed Central

    Wang, Junjie; Wang, Pu

    2014-01-01

    Large-scale daily commuting data were combined with detailed geographical information system (GIS) data to analyze the loss of transport efficiency caused by drivers’ uncoordinated routing in urban road networks. We used Price of Anarchy (POA) to quantify the loss of transport efficiency and found that both volume and distribution of human mobility demand determine the POA. In order to reduce POA, a small number of highways require considerable decreases in traffic, and their neighboring arterial roads need to attract more traffic. The magnitude of the adjustment in traffic flow can be estimated using the fundamental measure traffic flow only, which is widely available and easy to collect. Surprisingly, the most congested roads or the roads with largest traffic flow were not those requiring the most reduction of traffic. This study can offer guidance for the optimal control of urban traffic and facilitate improvements in the efficiency of transport networks. PMID:25349995

  18. Satellite switched FDMA advanced communication technology satellite program

    NASA Technical Reports Server (NTRS)

    Atwood, S.; Higton, G. H.; Wood, K.; Kline, A.; Furiga, A.; Rausch, M.; Jan, Y.

    1982-01-01

    The satellite switched frequency division multiple access system provided a detailed system architecture that supports a point to point communication system for long haul voice, video and data traffic between small Earth terminals at Ka band frequencies at 30/20 GHz. A detailed system design is presented for the space segment, small terminal/trunking segment at network control segment for domestic traffic model A or B, each totaling 3.8 Gb/s of small terminal traffic and 6.2 Gb/s trunk traffic. The small terminal traffic (3.8 Gb/s) is emphasized, for the satellite router portion of the system design, which is a composite of thousands of Earth stations with digital traffic ranging from a single 32 Kb/s CVSD voice channel to thousands of channels containing voice, video and data with a data rate as high as 33 Mb/s. The system design concept presented, effectively optimizes a unique frequency and channelization plan for both traffic models A and B with minimum reorganization of the satellite payload transponder subsystem hardware design. The unique zoning concept allows multiple beam antennas while maximizing multiple carrier frequency reuse. Detailed hardware design estimates for an FDMA router (part of the satellite transponder subsystem) indicate a weight and dc power budget of 353 lbs, 195 watts for traffic model A and 498 lbs, 244 watts for traffic model B.

  19. A spatial editing and validation process for short count traffic data : final report, July 2006.

    DOT National Transportation Integrated Search

    2006-07-07

    The Traffic Survey Unit (TSU) manages 40,000 traffic monitoring stations, of which 25,000 are updated annually. : These counts obtained by TSU play a crucial role in allocation of resources for the maintenance, upgrade, and : expansion of traffic inf...

  20. Pedalcylists. Traffic Safety Facts, 2000.

    ERIC Educational Resources Information Center

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

    This document provides statistical information on traffic accidents involving U.S. bicyclists. Data include: (1) trends in pedalcyclist and total traffic fatalities, 1990-2000; (2) non-occupant traffic fatalities, 1990-2000; (3) pedalcyclists killed and injured, and fatality and injury rates, by age and sex, 2000; and (4) pedalcyclist traffic…

  1. [A spatially explicit analysis of traffic accidents involving pedestrians and cyclists in Berlin].

    PubMed

    Lakes, Tobia

    2017-12-01

    In many German cities and counties, sustainable mobility concepts that strengthen pedestrian and cyclist traffic are promoted. From the perspectives of urban development, traffic planning and public healthcare, a spatially differentiated analysis of traffic accident data is decisive. 1) The identification of spatial and temporal patterns of the distribution of accidents involving cyclists and pedestrians, 2) the identification of hotspots and exploration of possible underlying causes and 3) the critical discussion of benefits and challenges of the results and the derivation of conclusions. Spatio-temporal distributions of data from accident statistics in Berlin involving pedestrians and cyclists from 2011 to 2015 were analysed with geographic information systems (GIS). While the total number of accidents remains relatively stable for pedestrian and cyclist accidents, the spatial distribution analysis shows, however, that there are significant spatial clusters (hotspots) of traffic accidents with a strong concentration in the inner city area. In a critical discussion, the benefits of geographic concepts are identified, such as spatially explicit health data (in this case traffic accident data), the importance of the integration of other data sources for the evaluation of the health impact of areas (traffic accident statistics of the police), and the possibilities and limitations of spatial-temporal data analysis (spatial point-density analyses) for the derivation of decision-supported recommendations and for the evaluation of policy measures of health prevention and of health-relevant urban development.

  2. Prediction of Traffic Complexity and Controller Workload in Mixed Equipage NextGen Environments

    NASA Technical Reports Server (NTRS)

    Lee, Paul U.; Prevot, Thomas

    2012-01-01

    Controller workload is a key factor in limiting en route air traffic capacity. Past efforts to quantify and predict workload have resulted in identifying objective metrics that correlate well with subjective workload ratings during current air traffic control operations. Although these metrics provide a reasonable statistical fit to existing data, they do not provide a good mechanism for estimating controller workload for future air traffic concepts and environments that make different assumptions about automation, enabling technologies, and controller tasks. One such future environment is characterized by en route airspace with a mixture of aircraft equipped with and without Data Communications (Data Comm). In this environment, aircraft with Data Comm will impact controller workload less than aircraft requiring voice communication, altering the close correlation between aircraft count and controller workload that exists in current air traffic operations. This paper outlines a new trajectory-based complexity (TBX) calculation that was presented to controllers during a human-in-the-loop simulation. The results showed that TBX accurately estimated the workload in a mixed Data Comm equipage environment and the resulting complexity values were understood and readily interpreted by the controllers. The complexity was represented as a "modified aircraft account" that weighted different complexity factors and summed them in such a way that the controllers could effectively treat them as aircraft count. The factors were also relatively easy to tune without an extensive data set. The results showed that the TBX approach is well suited for presenting traffic complexity in future air traffic environments.

  3. Estimation of carbon dioxide emissions per urban center link unit using data collected by the Advanced Traffic Information System in Daejeon, Korea

    NASA Astrophysics Data System (ADS)

    Ryu, B. Y.; Jung, H. J.; Bae, S. H.; Choi, C. U.

    2013-12-01

    CO2 emissions on roads in urban centers substantially affect global warming. It is important to quantify CO2 emissions in terms of the link unit in order to reduce these emissions on the roads. Therefore, in this study, we utilized real-time traffic data and attempted to develop a methodology for estimating CO2 emissions per link unit. Because of the recent development of the vehicle-to-infrastructure (V2I) communication technology, data from probe vehicles (PVs) can be collected and speed per link unit can be calculated. Among the existing emission calculation methodologies, mesoscale modeling, which is a representative modeling measurement technique, requires speed and traffic data per link unit. As it is not feasible to install fixed detectors at every link for traffic data collection, in this study, we developed a model for traffic volume estimation by utilizing the number of PVs that can be additionally collected when the PV data are collected. Multiple linear regression and an artificial neural network (ANN) were used for estimating the traffic volume. The independent variables and input data for each model are the number of PVs, travel time index (TTI), the number of lanes, and time slots. The result from the traffic volume estimate model shows that the mean absolute percentage error (MAPE) of the ANN is 18.67%, thus proving that it is more effective. The ANN-based traffic volume estimation served as the basis for the calculation of emissions per link unit. The daily average emissions for Daejeon, where this study was based, were 2210.19 ton/day. By vehicle type, passenger cars accounted for 71.28% of the total emissions. By road, Gyeryongro emitted 125.48 ton/day, accounting for 5.68% of the total emission, the highest percentage of all roads. In terms of emissions per kilometer, Hanbatdaero had the highest emission volume, with 7.26 ton/day/km on average. This study proves that real-time traffic data allow an emissions estimate in terms of the link unit. Furthermore, an analysis of CO2 emissions can support traffic management to make decisions related to the reduction of carbon emissions.

  4. Crash Frequency Modeling Using Real-Time Environmental and Traffic Data and Unbalanced Panel Data Models

    PubMed Central

    Chen, Feng; Chen, Suren; Ma, Xiaoxiang

    2016-01-01

    Traffic and environmental conditions (e.g., weather conditions), which frequently change with time, have a significant impact on crash occurrence. Traditional crash frequency models with large temporal scales and aggregated variables are not sufficient to capture the time-varying nature of driving environmental factors, causing significant loss of critical information on crash frequency modeling. This paper aims at developing crash frequency models with refined temporal scales for complex driving environments, with such an effort providing more detailed and accurate crash risk information which can allow for more effective and proactive traffic management and law enforcement intervention. Zero-inflated, negative binomial (ZINB) models with site-specific random effects are developed with unbalanced panel data to analyze hourly crash frequency on highway segments. The real-time driving environment information, including traffic, weather and road surface condition data, sourced primarily from the Road Weather Information System, is incorporated into the models along with site-specific road characteristics. The estimation results of unbalanced panel data ZINB models suggest there are a number of factors influencing crash frequency, including time-varying factors (e.g., visibility and hourly traffic volume) and site-varying factors (e.g., speed limit). The study confirms the unique significance of the real-time weather, road surface condition and traffic data to crash frequency modeling. PMID:27322306

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

    DOT National Transportation Integrated Search

    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...

  6. 14 CFR 271.5 - Carrier revenues.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... one-line passengers; and (2) The traffic (including both local and beyond traffic) projected to flow..., Department estimates, and on traffic levels in the market at issue when such data are available. (b) The... proposed fare with the fare charged in other city-pair markets of similar distances and traffic densities...

  7. 14 CFR 271.5 - Carrier revenues.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... one-line passengers; and (2) The traffic (including both local and beyond traffic) projected to flow..., Department estimates, and on traffic levels in the market at issue when such data are available. (b) The... proposed fare with the fare charged in other city-pair markets of similar distances and traffic densities...

  8. 14 CFR 271.5 - Carrier revenues.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... one-line passengers; and (2) The traffic (including both local and beyond traffic) projected to flow..., Department estimates, and on traffic levels in the market at issue when such data are available. (b) The... proposed fare with the fare charged in other city-pair markets of similar distances and traffic densities...

  9. 14 CFR 271.5 - Carrier revenues.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... one-line passengers; and (2) The traffic (including both local and beyond traffic) projected to flow..., Department estimates, and on traffic levels in the market at issue when such data are available. (b) The... proposed fare with the fare charged in other city-pair markets of similar distances and traffic densities...

  10. Pedestrians. Traffic Safety Facts, 2000.

    ERIC Educational Resources Information Center

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

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

  11. Traffic Safety Facts, 2001: Pedestrians.

    ERIC Educational Resources Information Center

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

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

  12. Using the Traffic monitoring guide to develop a truck weight sampling procedure for use in Virginia : final report.

    DOT National Transportation Integrated Search

    1992-01-01

    The Traffic Monitoring Guide (TMG) provides a method for the development of a statistically based procedure to monitor traffic characteristics such as traffic loadings. Truck weight data in particular are a major element of the pavement management pr...

  13. Comparison of modeled traffic exposure zones using on-road air pollution measurements

    EPA Science Inventory

    Modeled traffic data were used to develop traffic exposure zones (TEZs) such as traffic delay, high volume, and transit routes in the Research Triangle area of North Carolina (USA). On-road air pollution measurements of nitrogen dioxide (NO2), carbon monoxide (CO), carbon dioxid...

  14. Modeling Traffic on the Web Graph

    NASA Astrophysics Data System (ADS)

    Meiss, Mark R.; Gonçalves, Bruno; Ramasco, José J.; Flammini, Alessandro; Menczer, Filippo

    Analysis of aggregate and individual Web requests shows that PageRank is a poor predictor of traffic. We use empirical data to characterize properties of Web traffic not reproduced by Markovian models, including both aggregate statistics such as page and link traffic, and individual statistics such as entropy and session size. As no current model reconciles all of these observations, we present an agent-based model that explains them through realistic browsing behaviors: (1) revisiting bookmarked pages; (2) backtracking; and (3) seeking out novel pages of topical interest. The resulting model can reproduce the behaviors we observe in empirical data, especially heterogeneous session lengths, reconciling the narrowly focused browsing patterns of individual users with the extreme variance in aggregate traffic measurements. We can thereby identify a few salient features that are necessary and sufficient to interpret Web traffic data. Beyond the descriptive and explanatory power of our model, these results may lead to improvements in Web applications such as search and crawling.

  15. Mixed Traffic Information Collection System based on Pressure Sensor

    NASA Astrophysics Data System (ADS)

    Liao, Wenzhe; Liu, Mingsheng; Meng, Qingli

    The traffic information collection is the base of Intelligent Traffic.At present, there exist mixed traffic situation in urban road in China. This paper researched and implemented a system through collecting the vehicle and bicycle mixed traffic flow parameters based on pressure sensor. According to information collection requirements, we selected pressure sensor, designed the data collection, storage and other hardware circuitries and information processing software. The experiment shows that the system can meet the demand of traffic information collection in the actual.

  16. Incidence of posttraumatic stress disorder after traffic accidents in Germany.

    PubMed

    Brand, Stephan; Otte, Dietmar; Petri, Maximilian; Decker, Sebastian; Stübig, Timo; Krettek, Christian; Müller, Christian W

    2014-01-01

    Posttraumatic stress disorder (PTSD) is possibly an overlooked diagnosis of victims suffering from traffic accidents sustaining serious to severe injuries. This paper investigates the incidence of PTSD after traffic accidents in Germany. Data from an accident research unit were analyzed in regard to collision details, and preclinical and clinical data. Preclinical data included details on crash circumstances and estimated injury severity as well as data on victims' conditions (e.g. heart rate, blood pressure, consciousness, breath rate). Clinical data included initial assessment in the emergency department, radiographic diagnoses, and basic life parameters comparable to the preclinical data as well as follow-up data on the daily ward. Data were collected in the German-In-Depth Accident Research study, and included gender, type of accident (e.g. type of vehicle, road conditions, rural or urban area), mental disorder, and AIS (Abbreviated Injury Scale) head score. AIS represent a scoring system to measure the injury severity of traffic accident victims. A total 258 out of 32807 data sets were included in this analysis. Data on accident and victims was collected on scene by specialized teams following established algorithms. Besides higher AIS Head scores for male motorcyclists compared to all other subgroups, no significant correlation was found between the mean maximum AIS score and the occurrence of PTSD. Furthermore, there was no correlation between higher AIS head scores, gender, or involvement in road traffic accidents and PTSD. In our study the overall incidence of PTSD after road traffic accidents was very low (0.78% in a total of 32.807 collected data sets) when compared to other published studies. The reason for this very low incidence of PTSD in our patient sample could be seen in an underestimation of the psychophysiological impact of traffic accidents on patients. Patients suffering from direct experiences of traumatic events such as a traffic accident and presenting with signs of clinically significant distress or impairment in social interactions should be treated in a team approach including not only trauma surgeons and surgical skilled staff but also psychophysiological experienced physicians.

  17. Smartlink - baseline for measurement of benefits.

    DOT National Transportation Integrated Search

    2015-11-16

    The North Carolina Department of Transportation (NCDOT) operates several traffic management centers across the state : along with accompanying field devices such as traffic condition data stations, traffic surveillance cameras, and variable : message...

  18. Ergodicity of Traffic Flow with Constant Penetration Rate for Traffic Monitoring via Floating Vehicle Technique

    NASA Astrophysics Data System (ADS)

    Gunawan, Fergyanto E.; Abbas, Bahtiar S.; Atmadja, Wiedjaja; Yoseph Chandra, Fajar; Agung, Alexander AS; Kusnandar, Erwin

    2014-03-01

    Traffic congestion in Asian megacities has become extremely worse, and any means to lessen the congestion level is urgently needed. Building an efficient mass transportation system is clearly necessary. However, implementing Intelligent Transportation Systems (ITS) have also been demonstrated effective in various advanced countries. Recently, the floating vehicle technique (FVT), an ITS implementation, has become cost effective to provide real-time traffic information with proliferation of the smartphones. Although many publications have discussed various issues related to the technique, none of them elaborates the discrepancy of a single floating car data (FCD) and the associated fleet data. This work addresses the issue based on an analysis of Sugiyama et al's experimental data. The results indicate that there is an optimum averaging time interval such that the estimated velocity by the FVT reasonably representing the traffic velocity.

  19. Heterogeneity Index for the Assessment of Relationship Between Land Use Pattern and Road Traffic Congestion in Apapa-Oworoshoki Express way, Lagos Metropolis

    NASA Astrophysics Data System (ADS)

    Alaigba, D. B.; Soumah, M.; Banjo, M. O.

    2017-05-01

    The problem of urban mobility is complicated by traffic delay, resulting from poor planning, high population density and poor condition of roads within urban spaces. This study assessed traffic congestion resulting from differential contribution made by various land-uses along Apapa-Oworoshoki expressway in Lagos metropolis. The data for this study was from both primary and secondary sources; GPS point data was collected at selected points for traffic volume count; observation of the nature of vehicular traffic congestion, and land use types along the corridor. Existing data on traffic count along the corridor, connectivity map and land use map sourced from relevant authorities were acquired. Traffic congestion within the area was estimated using volume capacity ratio (V/C). Heterogeneity Index was developed and used to quantify the percentage contribution to traffic volume from various land-use categories. Analytical Hierarchical Processing (AHP) and knowledge-based weighting were used to rank the importance of different heterogeneity indices. Results showed significant relationship between the degree of heterogeneity of the land use pattern and road traffic congestion. Volume Capacity Ratio computed revealed that the route corridor exceeds its designed capacity in the southward direction between the hours of 8am and 12pm on working days. Five major nodes were analyzed along the corridor, and were all above the expected Passenger Car Unit (PCU), these are "Oshodi" 15 %, "Airport junction" 10 %, "Cele bus stop" 21 %, "Mile 2" 14 %, "Berger" 15 % and "Tincan bus stop" 33 % indicating heavy traffic congestion.

  20. FAST-TRAC evaluation : evaluation summary report

    DOT National Transportation Integrated Search

    FAST-TRAC is an Intelligent Transportation System (ITS) that integrates advanced traffic control with a variety of advanced traffic information systems through centralized collection, processing, and dissemination of traffic data. The Road Commission...

  1. Effect of Pokémon GO on incidence of fatal traffic injuries: a population-based quasi-experimental study using the national traffic collisions database in Japan.

    PubMed

    Ono, Sachiko; Ono, Yosuke; Michihata, Nobuaki; Sasabuchi, Yusuke; Yasunaga, Hideo

    2017-10-12

    Pokémon GO (Niantic Labs, released on 22 July 2016 in Japan) is an augmented reality game that gained huge popularity worldwide. Despite concern about Pokémon GO-related traffic collisions, the effect of playing Pokémon GO on the incidence of traffic injuries remains unknown. We performed a population-based quasi-experimental study using national data from the Institute for Traffic Accident Research and Data Analysis, Japan. The outcome was incidence of traffic injuries. Of 127 082 000 people in Japan, 886 fatal traffic injuries were observed between 1 June and 31 August in 2016. Regression discontinuity analysis showed a non-significant change in incidence of fatal traffic injuries after the Pokémon GO release (0.017 deaths per million, 95%CI -0.036 to 0.071). This finding was similar to that obtained from a difference-in-differences analysis. Effect of Pokémon GO on fatal traffic injuries may be negligible. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  2. Predicting Average Vehicle Speed in Two Lane Highways Considering Weather Condition and Traffic Characteristics

    NASA Astrophysics Data System (ADS)

    Mirbaha, Babak; Saffarzadeh, Mahmoud; AmirHossein Beheshty, Seyed; Aniran, MirMoosa; Yazdani, Mirbahador; Shirini, Bahram

    2017-10-01

    Analysis of vehicle speed with different weather condition and traffic characteristics is very effective in traffic planning. Since the weather condition and traffic characteristics vary every day, the prediction of average speed can be useful in traffic management plans. In this study, traffic and weather data for a two-lane highway located in Northwest of Iran were selected for analysis. After merging traffic and weather data, the linear regression model was calibrated for speed prediction using STATA12.1 Statistical and Data Analysis software. Variables like vehicle flow, percentage of heavy vehicles, vehicle flow in opposing lane, percentage of heavy vehicles in opposing lane, rainfall (mm), snowfall and maximum daily wind speed more than 13m/s were found to be significant variables in the model. Results showed that variables of vehicle flow and heavy vehicle percent acquired the positive coefficient that shows, by increasing these variables the average vehicle speed in every weather condition will also increase. Vehicle flow in opposing lane, percentage of heavy vehicle in opposing lane, rainfall amount (mm), snowfall and maximum daily wind speed more than 13m/s acquired the negative coefficient that shows by increasing these variables, the average vehicle speed will decrease.

  3. Understanding widely scattered traffic flows, the capacity drop, and platoons as effects of variance-driven time gaps

    NASA Astrophysics Data System (ADS)

    Treiber, Martin; Kesting, Arne; Helbing, Dirk

    2006-07-01

    We investigate the adaptation of the time headways in car-following models as a function of the local velocity variance, which is a measure of the inhomogeneity of traffic flow. We apply this mechanism to several car-following models and simulate traffic breakdowns in open systems with an on-ramp as bottleneck and in a closed ring road. Single-vehicle data and one-minute aggregated data generated by several virtual detectors show a semiquantitative agreement with microscopic and flow-density data from the Dutch freeway A9. This includes the observed distributions of the net time headways for free and congested traffic, the velocity variance as a function of density, and the fundamental diagram. The modal value of the time headway distribution is shifted by a factor of about 2 under congested conditions. Macroscopically, this corresponds to the capacity drop at the transition from free to congested traffic. The simulated fundamental diagram shows free, synchronized, and jammed traffic, and a wide scattering in the congested traffic regime. We explain this by a self-organized variance-driven process that leads to the spontaneous formation and decay of long-lived platoons even for a deterministic dynamics on a single lane.

  4. Traffic forecasting report : 2007.

    DOT National Transportation Integrated Search

    2008-05-01

    This is the sixth edition of the Traffic Forecasting Report (TFR). This edition of the TFR contains the latest (predominantly 2007) forecasting/modeling data as follows: : Functional class average traffic volume growth rates and trends : Vehi...

  5. Data mining the Kansas traffic-crash database : final report.

    DOT National Transportation Integrated Search

    2009-08-01

    Traffic crashes results from the interaction of different parameters which includes highway geometrics, traffic characteristics and human factors. Geometric variables include number of lanes, lane width, median width, shoulder width, roadway section ...

  6. Data mining the Kansas traffic-crash database : summary.

    DOT National Transportation Integrated Search

    2009-08-01

    Traffic crashes results from the interaction of different parameters which includes highway geometrics, traffic : characteristics and human factors. Geometric variables include number of lanes, lane width, median width, shoulder : width, roadway sect...

  7. Frankfurt, Germany: 1030/1090 MegaHertz Signal Analysis

    DOT National Transportation Integrated Search

    1996-07-01

    The Data Link Test Analysis System (DATAS) was used in the Frankfort, Germany : to collect data in the frequency band used by Air Traffic Control Radar : Beacon (ATCRBS), Mode Select (Mode S), and Traffic Alert and Collision : Avoidance (TCAS). Data ...

  8. Transition Characteristic Analysis of Traffic Evolution Process for Urban Traffic Network

    PubMed Central

    Chen, Hong; Li, Yang

    2014-01-01

    The characterization of the dynamics of traffic states remains fundamental to seeking for the solutions of diverse traffic problems. To gain more insights into traffic dynamics in the temporal domain, this paper explored temporal characteristics and distinct regularity in the traffic evolution process of urban traffic network. We defined traffic state pattern through clustering multidimensional traffic time series using self-organizing maps and construct a pattern transition network model that is appropriate for representing and analyzing the evolution progress. The methodology is illustrated by an application to data flow rate of multiple road sections from Network of Shenzhen's Nanshan District, China. Analysis and numerical results demonstrated that the methodology permits extracting many useful traffic transition characteristics including stability, preference, activity, and attractiveness. In addition, more information about the relationships between these characteristics was extracted, which should be helpful in understanding the complex behavior of the temporal evolution features of traffic patterns. PMID:24982969

  9. Incorporating real-time traffic and weather data to explore road accident likelihood and severity in urban arterials.

    PubMed

    Theofilatos, Athanasios

    2017-06-01

    The effective treatment of road accidents and thus the enhancement of road safety is a major concern to societies due to the losses in human lives and the economic and social costs. The investigation of road accident likelihood and severity by utilizing real-time traffic and weather data has recently received significant attention by researchers. However, collected data mainly stem from freeways and expressways. Consequently, the aim of the present paper is to add to the current knowledge by investigating accident likelihood and severity by exploiting real-time traffic and weather data collected from urban arterials in Athens, Greece. Random Forests (RF) are firstly applied for preliminary analysis purposes. More specifically, it is aimed to rank candidate variables according to their relevant importance and provide a first insight on the potential significant variables. Then, Bayesian logistic regression as well finite mixture and mixed effects logit models are applied to further explore factors associated with accident likelihood and severity respectively. Regarding accident likelihood, the Bayesian logistic regression showed that variations in traffic significantly influence accident occurrence. On the other hand, accident severity analysis revealed a generally mixed influence of traffic variations on accident severity, although international literature states that traffic variations increase severity. Lastly, weather parameters did not find to have a direct influence on accident likelihood or severity. The study added to the current knowledge by incorporating real-time traffic and weather data from urban arterials to investigate accident occurrence and accident severity mechanisms. The identification of risk factors can lead to the development of effective traffic management strategies to reduce accident occurrence and severity of injuries in urban arterials. Copyright © 2017 Elsevier Ltd and National Safety Council. All rights reserved.

  10. A novel interacting multiple model based network intrusion detection scheme

    NASA Astrophysics Data System (ADS)

    Xin, Ruichi; Venkatasubramanian, Vijay; Leung, Henry

    2006-04-01

    In today's information age, information and network security are of primary importance to any organization. Network intrusion is a serious threat to security of computers and data networks. In internet protocol (IP) based network, intrusions originate in different kinds of packets/messages contained in the open system interconnection (OSI) layer 3 or higher layers. Network intrusion detection and prevention systems observe the layer 3 packets (or layer 4 to 7 messages) to screen for intrusions and security threats. Signature based methods use a pre-existing database that document intrusion patterns as perceived in the layer 3 to 7 protocol traffics and match the incoming traffic for potential intrusion attacks. Alternately, network traffic data can be modeled and any huge anomaly from the established traffic pattern can be detected as network intrusion. The latter method, also known as anomaly based detection is gaining popularity for its versatility in learning new patterns and discovering new attacks. It is apparent that for a reliable performance, an accurate model of the network data needs to be established. In this paper, we illustrate using collected data that network traffic is seldom stationary. We propose the use of multiple models to accurately represent the traffic data. The improvement in reliability of the proposed model is verified by measuring the detection and false alarm rates on several datasets.

  11. Under-reporting of road traffic mortality in developing countries: application of a capture-recapture statistical model to refine mortality estimates.

    PubMed

    Samuel, Jonathan C; Sankhulani, Edward; Qureshi, Javeria S; Baloyi, Paul; Thupi, Charles; Lee, Clara N; Miller, William C; Cairns, Bruce A; Charles, Anthony G

    2012-01-01

    Road traffic injuries are a major cause of preventable death in sub-Saharan Africa. Accurate epidemiologic data are scarce and under-reporting from primary data sources is common. Our objectives were to estimate the incidence of road traffic deaths in Malawi using capture-recapture statistical analysis and determine what future efforts will best improve upon this estimate. Our capture-recapture model combined primary data from both police and hospital-based registries over a one year period (July 2008 to June 2009). The mortality incidences from the primary data sources were 0.075 and 0.051 deaths/1000 person-years, respectively. Using capture-recapture analysis, the combined incidence of road traffic deaths ranged 0.192-0.209 deaths/1000 person-years. Additionally, police data were more likely to include victims who were male, drivers or pedestrians, and victims from incidents with greater than one vehicle involved. We concluded that capture-recapture analysis is a good tool to estimate the incidence of road traffic deaths, and that capture-recapture analysis overcomes limitations of incomplete data sources. The World Health Organization estimated incidence of road traffic deaths for Malawi utilizing a binomial regression model and survey data and found a similar estimate despite strikingly different methods, suggesting both approaches are valid. Further research should seek to improve capture-recapture data through utilization of more than two data sources and improving accuracy of matches by minimizing missing data, application of geographic information systems, and use of names and civil registration numbers if available.

  12. Under-Reporting of Road Traffic Mortality in Developing Countries: Application of a Capture-Recapture Statistical Model to Refine Mortality Estimates

    PubMed Central

    Samuel, Jonathan C.; Sankhulani, Edward; Qureshi, Javeria S.; Baloyi, Paul; Thupi, Charles; Lee, Clara N.; Miller, William C.; Cairns, Bruce A.; Charles, Anthony G.

    2012-01-01

    Road traffic injuries are a major cause of preventable death in sub-Saharan Africa. Accurate epidemiologic data are scarce and under-reporting from primary data sources is common. Our objectives were to estimate the incidence of road traffic deaths in Malawi using capture-recapture statistical analysis and determine what future efforts will best improve upon this estimate. Our capture-recapture model combined primary data from both police and hospital-based registries over a one year period (July 2008 to June 2009). The mortality incidences from the primary data sources were 0.075 and 0.051 deaths/1000 person-years, respectively. Using capture-recapture analysis, the combined incidence of road traffic deaths ranged 0.192–0.209 deaths/1000 person-years. Additionally, police data were more likely to include victims who were male, drivers or pedestrians, and victims from incidents with greater than one vehicle involved. We concluded that capture-recapture analysis is a good tool to estimate the incidence of road traffic deaths, and that capture-recapture analysis overcomes limitations of incomplete data sources. The World Health Organization estimated incidence of road traffic deaths for Malawi utilizing a binomial regression model and survey data and found a similar estimate despite strikingly different methods, suggesting both approaches are valid. Further research should seek to improve capture-recapture data through utilization of more than two data sources and improving accuracy of matches by minimizing missing data, application of geographic information systems, and use of names and civil registration numbers if available. PMID:22355338

  13. The burden of road traffic injuries in Nigeria: results of a population-based survey.

    PubMed

    Labinjo, M; Juillard, C; Kobusingye, O C; Hyder, A A

    2009-06-01

    Mortality from road traffic injuries in sub-Saharan Africa is among the highest in the world, yet data from the region are sparse. To date, no multi-site population-based survey on road traffic injuries has been reported from Nigeria, the most populated country in Africa. To explore the epidemiology of road traffic injury in Nigeria and provide data on the populations affected and risk factors for road traffic injury. Data from a population-based survey using two-stage stratified cluster sampling. SUBJECTS/ SETTING: Road traffic injury status and demographic information were collected on 3082 respondents living in 553 households in seven of Nigeria's 37 states. Incidence rates were estimated with confidence intervals based on a Poisson distribution; Poisson regression analysis was used to calculate relative risks for associated factors. The overall road traffic injury rate was 41 per 1000 population (95% CI 34 to 49), and mortality from road traffic injuries was 1.6 per 1000 population (95% CI 0.5 to 3.8). Motorcycle crashes accounted for 54% of all road traffic injuries. The road traffic injury rates found for rural and urban respondents were not significantly different. Increased risk of injury was associated with male gender among those aged 18-44 years, with a relative risk of 2.96 when compared with women in the same age range (95% CI 1.72 to 5.09, p<0.001). The road traffic injury rates found in this survey highlight a neglected public health problem in Nigeria. Simple extrapolations from this survey suggest that over 4 million people may be injured and as many as 200 000 potentially killed as the result of road traffic crashes annually in Nigeria. Appropriate interventions in both the health and transport sectors are needed to address this significant cause of morbidity and mortality in Nigeria.

  14. Spacelab system analysis: The modified free access protocol: An access protocol for communication systems with periodic and Poisson traffic

    NASA Technical Reports Server (NTRS)

    Ingels, Frank; Owens, John; Daniel, Steven

    1989-01-01

    The protocol definition and terminal hardware for the modified free access protocol, a communications protocol similar to Ethernet, are developed. A MFA protocol simulator and a CSMA/CD math model are also developed. The protocol is tailored to communication systems where the total traffic may be divided into scheduled traffic and Poisson traffic. The scheduled traffic should occur on a periodic basis but may occur after a given event such as a request for data from a large number of stations. The Poisson traffic will include alarms and other random traffic. The purpose of the protocol is to guarantee that scheduled packets will be delivered without collision. This is required in many control and data collection systems. The protocol uses standard Ethernet hardware and software requiring minimum modifications to an existing system. The modification to the protocol only affects the Ethernet transmission privileges and does not effect the Ethernet receiver.

  15. Truck Drivers' Experiences and Perspectives Regarding Factors Influencing Traffic Accidents: A Qualitative Study.

    PubMed

    Karimi Moonaghi, Hossein; Ranjbar, Hossein; Heydari, Abbas; Scurlock-Evans, Laura

    2015-08-01

    Traffic accidents are a major public health problem, leading to death and disability. Although pertinent studies have been conducted, little data are available in Iran. This study explored the experiences of truck drivers and their perspectives regarding factors contributing to traffic accidents. Eighteen truck drivers, purposively sampled, participated in semi-structured interviews. Data were analyzed using qualitative content analysis. A main theme, lack of ability to control stress, emerged as a factor influencing the incidence of traffic accidents. This main theme was found to have three subthemes: poor organization of the job, lack of workplace facilities and proper equipment, and unsupportive environment. Although several factors were found to contribute to traffic accidents, their effects were not independent, and all were considered significant. Identifying factors that contribute to traffic accidents requires a systematic and holistic approach. Findings could be used by the transportation industry and community health centers to prevent traffic accidents. © 2015 The Author(s).

  16. Optimized Structure of the Traffic Flow Forecasting Model With a Deep Learning Approach.

    PubMed

    Yang, Hao-Fan; Dillon, Tharam S; Chen, Yi-Ping Phoebe

    2017-10-01

    Forecasting accuracy is an important issue for successful intelligent traffic management, especially in the domain of traffic efficiency and congestion reduction. The dawning of the big data era brings opportunities to greatly improve prediction accuracy. In this paper, we propose a novel model, stacked autoencoder Levenberg-Marquardt model, which is a type of deep architecture of neural network approach aiming to improve forecasting accuracy. The proposed model is designed using the Taguchi method to develop an optimized structure and to learn traffic flow features through layer-by-layer feature granulation with a greedy layerwise unsupervised learning algorithm. It is applied to real-world data collected from the M6 freeway in the U.K. and is compared with three existing traffic predictors. To the best of our knowledge, this is the first time that an optimized structure of the traffic flow forecasting model with a deep learning approach is presented. The evaluation results demonstrate that the proposed model with an optimized structure has superior performance in traffic flow forecasting.

  17. The impact of traffic emissions on air quality in the Berlin-Brandenburg region - a case study on cycling scenarios

    NASA Astrophysics Data System (ADS)

    Kuik, F.; Lauer, A.; von Schneidemesser, E.; Butler, T. M.

    2016-12-01

    Many European cities continue to struggle with exceedances of NO2 limit values at measurement sites near roads, of which a large contribution is attributed to emissions from traffic. In this study, we explore how urban air quality can be improved with different traffic measures using the example of the Berlin-Brandenburg region. In order to simulate urban background air quality we use the Weather Research and Forecasting model with chemistry (WRF-Chem) at a horizontal resolution of 1km. We use emission input data at a horizontal resolution of 1km obtained by downscaling TNO-MACC III emissions based on local proxy data including population and traffic densities. In addition we use a statistical approach combining the simulated urban background concentrations with information on traffic densities to estimate NO2 at street level. This helps assessing whether the emission scenarios studied here can lead to significant reductions in NO2 concentrations at street level. The emission scenarios in this study represent a range of scenarios in which car traffic is replaced with bicycle traffic. Part of this study was an initial discussion phase with stakeholders, including policy makers and NGOs. The discussions have shown that the different stakeholders are interested in a scientific assessment of the impact of replacing car traffic with bicycle traffic in the Berlin-Brandenburg urban area. Local policy makers responsible for city planning and implementing traffic measures can make best use of scientific modeling results if input data and scenarios are as realistic as possible. For these reasons, the scenarios cover very idealized optimistic ("all passenger cars are replaced by bicycles") and pessimistic ("all cyclists are replaced by cars") scenarios to explore the sensitivity of simulated urban background air quality to these changes, as well as additional scenarios based on city-specific data to analyze more realistic situations. Of particular interest is how these impact street level NO2 concentrations.

  18. LINEBACkER: Bio-inspired Data Reduction Toward Real Time Network Traffic Analysis

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

    Teuton, Jeremy R.; Peterson, Elena S.; Nordwall, Douglas J.

    Abstract—One essential component of resilient cyber applications is the ability to detect adversaries and protect systems with the same flexibility adversaries will use to achieve their goals. Current detection techniques do not enable this degree of flexibility because most existing applications are built using exact or regular-expression matching to libraries of rule sets. Further, network traffic defies traditional cyber security approaches that focus on limiting access based on the use of passwords and examination of lists of installed or downloaded programs. These approaches do not readily apply to network traffic occurring beyond the access control point, and when the datamore » in question are combined control and payload data of ever increasing speed and volume. Manual analysis of network traffic is not normally possible because of the magnitude of the data that is being exchanged and the length of time that this analysis takes. At the same time, using an exact matching scheme to identify malicious traffic in real time often fails because the lists against which such searches must operate grow too large. In this work, we introduce an alternative method for cyber network detection based on similarity-measuring algorithms for gene sequence analysis. These methods are ideal because they were designed to identify similar but nonidentical sequences. We demonstrate that our method is generally applicable to the problem of network traffic analysis by illustrating its use in two different areas both based on different attributes of network traffic. Our approach provides a logical framework for organizing large collections of network data, prioritizing traffic of interest to human analysts, and makes it possible to discover traffic signatures without the bias introduced by expert-directed signature generation. Pattern recognition on reduced representations of network traffic offers a fast, efficient, and more robust way to detect anomalies.« less

  19. Preliminary study on alterations of altitude road traffic in China from 2006 to 2013

    PubMed Central

    Zhao, Hui; Yin, Zhiyong; Xiang, Hongyi; Liao, Zhikang; Wang, Zhengguo

    2017-01-01

    Introduction Road traffic can play an important role in strengthening regional economic activities, especially at high altitude, and it is necessary to know important traffic-related information. Although previous studies reported on road traffic in China, there has been little research on high-altitude road traffic to date. Method The annual official census of road traffic safety from 2006 to 2013 was used to obtain data on the general population, registered drivers, registered vehicles, newly built roads, road traffic accidents (RTAs), mortality rate per 100 000 populations and per 10 000 vehicles in high-altitude provinces, including Tibet, Qinghai, Xinjiang, Gansu, Yunnan, Sichuan, and Chongqing. These provincial data were reviewed retrospectively, with the national data as the reference. Statistical analysis (i.e., t test) was used to compare the estimated average annual change rate of population, number of registered drivers, registered vehicles, and newly built roads in high-altitude provinces with the national rates. Results Compared with the national data, there are significantly higher annual rates of population growth in Tibet and Xinjiang, registered drivers in Gansu, registered vehicles in Gansu, Sichuan, and Chongqing, and newly built roads in Tibet and Qinghai. Among the investigated provinces, Tibet, Qinghai, and Yunnan had a higher proportion of the roads with the high class. RTAs and RTA-induced casualties in the high-altitude provinces indicated a decreasing trend. The mortality rate per 10 000 vehicles and per 100 000 populations showed a decreasing trend, while the RTA-related mortality rate in Tibet, Qinghai, Xinjiang and Gansu remained high. Conclusions Major changes for road traffic in high-altitude provinces have occurred over the past decade; however, the RTA-related mortality rate in high-altitude provinces has remained high. This study furthers understanding about road traffic safety in China; further studies on road traffic safety at high altitude should be performed. PMID:28187203

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

    PubMed Central

    Yan, Lixin; Zhang, Yishi; He, Yi; Gao, Song; Zhu, Dunyao; Ran, Bin; Wu, Qing

    2016-01-01

    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. PMID:27420073

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

    PubMed

    Yan, Lixin; Zhang, Yishi; He, Yi; Gao, Song; Zhu, Dunyao; Ran, Bin; Wu, Qing

    2016-07-13

    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.

  2. Review of modelling air pollution from traffic at street-level - The state of the science.

    PubMed

    Forehead, H; Huynh, N

    2018-06-13

    Traffic emissions are a complex and variable cocktail of toxic chemicals. They are the major source of atmospheric pollution in the parts of cities where people live, commute and work. Reducing exposure requires information about the distribution and nature of emissions. Spatially and temporally detailed data are required, because both the rate of production and the composition of emissions vary significantly with time of day and with local changes in wind, traffic composition and flow. Increasing computer processing power means that models can accept highly detailed inputs of fleet, fuels and road networks. The state of the science models can simulate the behaviour and emissions of all the individual vehicles on a road network, with resolution of a second and tens of metres. The chemistry of the simulated emissions is also highly resolved, due to consideration of multiple engine processes, fuel evaporation and tyre wear. Good results can be achieved with both commercially available and open source models. The extent of a simulation is usually limited by processing capacity; the accuracy by the quality of traffic data. Recent studies have generated real time, detailed emissions data by using inputs from novel traffic sensing technologies and data from intelligent traffic systems (ITS). Increasingly, detailed pollution data is being combined with spatially resolved demographic or epidemiological data for targeted risk analyses. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Forecasting short-term data center network traffic load with convolutional neural networks.

    PubMed

    Mozo, Alberto; Ordozgoiti, Bruno; Gómez-Canaval, Sandra

    2018-01-01

    Efficient resource management in data centers is of central importance to content service providers as 90 percent of the network traffic is expected to go through them in the coming years. In this context we propose the use of convolutional neural networks (CNNs) to forecast short-term changes in the amount of traffic crossing a data center network. This value is an indicator of virtual machine activity and can be utilized to shape the data center infrastructure accordingly. The behaviour of network traffic at the seconds scale is highly chaotic and therefore traditional time-series-analysis approaches such as ARIMA fail to obtain accurate forecasts. We show that our convolutional neural network approach can exploit the non-linear regularities of network traffic, providing significant improvements with respect to the mean absolute and standard deviation of the data, and outperforming ARIMA by an increasingly significant margin as the forecasting granularity is above the 16-second resolution. In order to increase the accuracy of the forecasting model, we exploit the architecture of the CNNs using multiresolution input distributed among separate channels of the first convolutional layer. We validate our approach with an extensive set of experiments using a data set collected at the core network of an Internet Service Provider over a period of 5 months, totalling 70 days of traffic at the one-second resolution.

  4. Forecasting short-term data center network traffic load with convolutional neural networks

    PubMed Central

    Ordozgoiti, Bruno; Gómez-Canaval, Sandra

    2018-01-01

    Efficient resource management in data centers is of central importance to content service providers as 90 percent of the network traffic is expected to go through them in the coming years. In this context we propose the use of convolutional neural networks (CNNs) to forecast short-term changes in the amount of traffic crossing a data center network. This value is an indicator of virtual machine activity and can be utilized to shape the data center infrastructure accordingly. The behaviour of network traffic at the seconds scale is highly chaotic and therefore traditional time-series-analysis approaches such as ARIMA fail to obtain accurate forecasts. We show that our convolutional neural network approach can exploit the non-linear regularities of network traffic, providing significant improvements with respect to the mean absolute and standard deviation of the data, and outperforming ARIMA by an increasingly significant margin as the forecasting granularity is above the 16-second resolution. In order to increase the accuracy of the forecasting model, we exploit the architecture of the CNNs using multiresolution input distributed among separate channels of the first convolutional layer. We validate our approach with an extensive set of experiments using a data set collected at the core network of an Internet Service Provider over a period of 5 months, totalling 70 days of traffic at the one-second resolution. PMID:29408936

  5. Traffic Data Quality Measurement : Final Report

    DOT National Transportation Integrated Search

    2004-09-15

    One of the foremost recommendations from the FHWA sponsored workshops on Traffic Data Quality (TDQ) in 2003 was a call for "guidelines and standards for calculating data quality measures." These guidelines and standards are expected to contain method...

  6. Traffic crash statistics report, 1994

    DOT National Transportation Integrated Search

    1995-01-01

    The information contained in this Traffic Crash Data booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashes...

  7. Traffic crash statistics report, 2004

    DOT National Transportation Integrated Search

    2005-01-01

    The information contained in this Traffic Crash Data booklet is extracted from law enforcement : agency long-form reports of traffic crashes. A law enforcement officer must submit a long-form crash report : when investigating: : Motor vehicle crashes...

  8. Tire-pavement and environmental traffic noise research study.

    DOT National Transportation Integrated Search

    2012-06-01

    In response to an interest in traffic noise, particularly tirepavement noise, CDOT elected to conduct tirepavement : noise research. Following a rigid set of testing protocols, data was collected on highway traffic : noise characteristics along wi...

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

    DOT National Transportation Integrated Search

    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, ...

  10. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-04

    DOT National Transportation Integrated Search

    2013-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  11. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2014-03

    DOT National Transportation Integrated Search

    2014-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  12. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-07

    DOT National Transportation Integrated Search

    2013-07-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  13. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-10

    DOT National Transportation Integrated Search

    2013-10-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  14. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-07

    DOT National Transportation Integrated Search

    2012-07-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  15. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-03

    DOT National Transportation Integrated Search

    2011-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  16. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-07

    DOT National Transportation Integrated Search

    2011-07-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  17. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-02

    DOT National Transportation Integrated Search

    2012-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  18. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-04

    DOT National Transportation Integrated Search

    2011-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  19. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-03

    DOT National Transportation Integrated Search

    2012-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  20. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2006-12

    DOT National Transportation Integrated Search

    2006-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  1. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-02

    DOT National Transportation Integrated Search

    2009-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  2. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-05

    DOT National Transportation Integrated Search

    2011-05-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  3. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2014-06

    DOT National Transportation Integrated Search

    2014-06-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  4. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-09

    DOT National Transportation Integrated Search

    2013-09-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  5. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-03

    DOT National Transportation Integrated Search

    2010-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  6. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-12

    DOT National Transportation Integrated Search

    2012-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  7. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-06

    DOT National Transportation Integrated Search

    2011-06-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  8. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-07

    DOT National Transportation Integrated Search

    2009-07-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  9. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-08

    DOT National Transportation Integrated Search

    2009-08-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  10. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2014-02

    DOT National Transportation Integrated Search

    2014-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  11. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-05

    DOT National Transportation Integrated Search

    2013-05-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  12. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-03

    DOT National Transportation Integrated Search

    2013-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  13. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-01

    DOT National Transportation Integrated Search

    2009-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  14. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2008-12

    DOT National Transportation Integrated Search

    2008-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  15. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-01

    DOT National Transportation Integrated Search

    2010-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  16. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-10

    DOT National Transportation Integrated Search

    2010-10-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  17. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-02

    DOT National Transportation Integrated Search

    2011-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  18. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2005-12

    DOT National Transportation Integrated Search

    2005-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  19. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-01

    DOT National Transportation Integrated Search

    2011-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  20. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-12

    DOT National Transportation Integrated Search

    2011-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  1. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-12

    DOT National Transportation Integrated Search

    2010-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  2. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-10

    DOT National Transportation Integrated Search

    2009-10-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  3. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-02

    DOT National Transportation Integrated Search

    2010-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  4. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-06

    DOT National Transportation Integrated Search

    2012-06-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  5. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-08

    DOT National Transportation Integrated Search

    2011-08-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  6. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-10

    DOT National Transportation Integrated Search

    2012-10-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  7. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2014-04

    DOT National Transportation Integrated Search

    2014-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  8. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-08

    DOT National Transportation Integrated Search

    2013-08-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  9. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-12

    DOT National Transportation Integrated Search

    2009-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  10. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-08

    DOT National Transportation Integrated Search

    2012-08-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  11. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-08

    DOT National Transportation Integrated Search

    2010-08-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  12. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-06

    DOT National Transportation Integrated Search

    2010-06-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  13. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-10

    DOT National Transportation Integrated Search

    2011-10-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  14. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-04

    DOT National Transportation Integrated Search

    2012-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  15. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-04

    DOT National Transportation Integrated Search

    2010-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  16. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-05

    DOT National Transportation Integrated Search

    2010-05-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  17. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-11

    DOT National Transportation Integrated Search

    2012-11-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  18. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2007-12

    DOT National Transportation Integrated Search

    2007-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  19. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-04

    DOT National Transportation Integrated Search

    2009-04-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  20. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2011-09

    DOT National Transportation Integrated Search

    2011-09-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  1. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-06

    DOT National Transportation Integrated Search

    2009-06-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  2. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-05

    DOT National Transportation Integrated Search

    2009-05-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  3. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2014-01

    DOT National Transportation Integrated Search

    2014-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  4. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-02

    DOT National Transportation Integrated Search

    2013-02-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  5. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2012-01

    DOT National Transportation Integrated Search

    2012-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  6. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2010-07

    DOT National Transportation Integrated Search

    2010-07-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  7. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-12

    DOT National Transportation Integrated Search

    2013-12-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  8. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2013-01

    DOT National Transportation Integrated Search

    2013-01-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  9. Data Bank 20 - Form 41 Schedule T-1 (T-100) - Monthly US Air Carrier Capacity and Traffic Data : [2009-03

    DOT National Transportation Integrated Search

    2009-03-01

    This CD presents traffic data for all certificated and commuter air carriers, both scheduled and nonscheduled. Data includes passenger-miles, ton-miles, seat-miles, load factors, hours, enplanements, and performance. Data are available since 1974.

  10. Detection of traffic incidents using nonlinear time series analysis

    NASA Astrophysics Data System (ADS)

    Fragkou, A. D.; Karakasidis, T. E.; Nathanail, E.

    2018-06-01

    In this study, we present results of the application of nonlinear time series analysis on traffic data for incident detection. More specifically, we analyze daily volume records of Attica Tollway (Greece) collected from sensors located at various locations. The analysis was performed using the Recurrence Plot (RP) and Recurrence Quantification Analysis (RQA) method of the volume data of the lane closest to the median. The results show that it is possible to identify, through the abrupt change of the dynamics of the system revealed by RPs and RQA, the occurrence of incidents on the freeway and differentiate from recurrent traffic congestion. The proposed methodology could be of interest for big data traffic analysis.

  11. Data on the determinants of the risk of fatalities, serious injuries and light injuries in traffic accidents on interurban roads in Spain.

    PubMed

    González, María Pilar Sánchez; Sotos, Francisco Escribano; Ponce, Ángel Tejada

    2018-06-01

    This article describes the data collection used to analyse the risk of fatalities and injuries resulting from traffic accidents on interurban roads in the provinces of Spain from 1999 to 2015. The database includes data on different factors related to accidents rates for each Spanish province. These data were used in the article entitled "Impact of provincial characteristics on the number of traffic accident victims on interurban roads in Spain" (Sánchez et al., 2018) [1].

  12. 2004-2006 Puget Sound Traffic Choices Study | Transportation Secure Data

    Science.gov Websites

    Center | NREL 04-2006 Puget Sound Traffic Choices Study 2004-2006 Puget Sound Traffic Choices Study The 2004-2006 Puget Sound Traffic Choices Study tested the hypothesis that time-of-day variable Administration for a pilot project on congestion-based tolling. Methodology To test the hypothesis, the study

  13. Traffic congestion and ozone precursor emissions in Bilbao, Spain.

    PubMed

    Ibarra-Berastegi, Gabriel; Madariaga, Imanol

    2003-01-01

    In urban environments, the measured levels of ozone are the result of the interaction between emissions of precursors (mainly VOCs and NOx) and meteorological effects. In this work, time series of daily values of ozone, measured at three locations in Bilbao (Spain), have been built. Then, after removing meteorological effects from them, ozone and traffic data have been analyzed jointly. The goal was to identify traffic situations and link them to ozone levels in the area of Bilbao. To remove meteorological effects from the selected ozone time series, the technique developed by Rao and Zurbenko was used. This is a widely used technique and, after its application, the fraction obtained from a given ozone time series represents an ozone forming capability attributable to emissions of precursors. This fraction is devoid of any meteorological influence and includes only the apportion of periodicities above 1.7 years. In the case of Bilbao, the ozone fractions obtained at three locations have been compared on that time scale with traffic data from the area. For the 1993-1996 period, a regression analysis of the ozone and traffic fractions due to periodicities above 1.7 years (long-term fractions), shows that traffic is the main explanatory factor for ozone with R2 ranging from 0.916 to 0.996 at the three locations studied. Analysis of these longterm fractions has made it possible to identify two traffic regimes for the whole area, associated to different profiles of ozone forming capability. The first one favors low ozone forming capability, and is associated with a situation of fluent traffic. The second one shows high ozone forming capability and represents congestion. Joint analysis of raw data of ozone and traffic do not show any clear pattern due to the strong masking effects that seasonal-meteorological effects (mainly radiation) have on the measured ozone signal. If only immission data of ozone are available, as in this case, a comparison between ozone and traffic can only be made on the long-term time scale, since that is the only fraction embedded in the ozone time series that can exclusively be attributed to emissions of precursors. This fact stresses the need to study the different fractions embedded in the time series of ozone measured levels separately. Though the coefficients obtained in the regression are only valid for the 1993-1996 period, these traffic regimes represent long-term targets (congestion or fluent traffic) that can inspire policies for a joint management of the traffic and pollution by ozone in the area of Bilbao beyond that period. The results of this work show the need of a joint management of ozone and traffic in Bilbao. Since an accurate knowledge of traffic was not available, the use of emission factors to relate traffic and actual ozone levels has not been possible. For this reason, this study has focused on the long-term fractions of traffic and ozone. In the future, if a more accurate knowledge of traffic is available, it will be possible to find relationships between traffic and ozone on all time scales.

  14. Memory effects in microscopic traffic models and wide scattering in flow-density data

    NASA Astrophysics Data System (ADS)

    Treiber, Martin; Helbing, Dirk

    2003-10-01

    By means of microscopic simulations we show that noninstantaneous adaptation of the driving behavior to the traffic situation together with the conventional method to measure flow-density data provides a possible explanation for the observed inverse-λ shape and the wide scattering of flow-density data in “synchronized” congested traffic. We model a memory effect in the response of drivers to the traffic situation for a wide class of car-following models by introducing an additional dynamical variable (the “subjective level of service”) describing the adaptation of drivers to the surrounding traffic situation during the past few minutes and couple this internal state to parameters of the underlying model that are related to the driving style. For illustration, we use the intelligent-driver model (IDM) as the underlying model, characterize the level of service solely by the velocity, and couple the internal variable to the IDM parameter “time gap” to model an increase of the time gap in congested traffic (“frustration effect”), which is supported by single-vehicle data. We simulate open systems with a bottleneck and obtain flow-density data by implementing “virtual detectors.” The shape, relative size, and apparent “stochasticity” of the region of the scattered data points agree nearly quantitatively with empirical data. Wide scattering is even observed for identical vehicles, although the proposed model is a time-continuous, deterministic, single-lane car-following model with a unique fundamental diagram.

  15. Controller evaluation of initial data link terminal air traffic control services : final report

    DOT National Transportation Integrated Search

    1991-01-01

    This document details the results the first Federal Aviation Administration : Technical Center investigation of the initial terminal air traffic control : services developed for transmission using Data Link technology. Initial Data : Link services we...

  16. Estimation of crossing conflict at signalized intersection using high-resolution traffic data : final report.

    DOT National Transportation Integrated Search

    2017-03-01

    This project explores the possibility of using high-resolution traffic signal data to evaluate intersection safety. : Traditional methods using historical crash data collected from infrequently and randomly occurring vehicle : collisions can require ...

  17. A data storage and retrieval model for Louisiana traffic operations data : final report.

    DOT National Transportation Integrated Search

    1995-09-01

    The type and amount of data managed by the Louisiana Department of Transportation and Development (DOTD) are huge. In many cases, these data are used to perform traffic engineering studies and highway safety analyses, among others. At the present tim...

  18. Demonstration of the application of traffic management center decision support tools.

    DOT National Transportation Integrated Search

    2013-03-01

    Decision support tools were developed in previous Florida Department of Transportation (FDOT) : research projects to allow for better analysis and visualization of historical traffic and incident : data, in support of incident management and traffic ...

  19. State traffic volume systems council estimation process.

    DOT National Transportation Integrated Search

    2004-10-01

    The Kentucky Transportation Cabinet has an immense traffic data collection program that is an essential source for many other programs. The Division of Planning processes traffic volume counts annually. These counts are maintained in the Counts Datab...

  20. Delaware's annual traffic statistical report, 2010

    DOT National Transportation Integrated Search

    2011-01-01

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  1. Delaware's annual traffic statistical report, 2005

    DOT National Transportation Integrated Search

    2006-04-10

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  2. Delaware's annual traffic statistical report, 2007

    DOT National Transportation Integrated Search

    2007-01-01

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  3. Delaware's annual traffic statistical report, 2006

    DOT National Transportation Integrated Search

    2006-01-01

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  4. Delaware's annual traffic statistical report, 2009

    DOT National Transportation Integrated Search

    2010-04-12

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  5. Delaware's annual traffic statistical report, 2011

    DOT National Transportation Integrated Search

    2012-01-01

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  6. Delaware's annual traffic statistical report, 2008

    DOT National Transportation Integrated Search

    2009-04-13

    The Traffic Control Section of the Delaware State Police is the repository for all Delaware traffic crash data. This includes all crash reports regardless of the geographical areas in which they occur or the policy agency conducting the investigation...

  7. Traffic prediction using wireless cellular networks : final report.

    DOT National Transportation Integrated Search

    2016-03-01

    The major objective of this project is to obtain traffic information from existing wireless : infrastructure. : In this project freeway traffic is identified and modeled using data obtained from existing : wireless cellular networks. Most of the prev...

  8. Exploiting geo-distributed clouds for a e-health monitoring system with minimum service delay and privacy preservation.

    PubMed

    Shen, Qinghua; Liang, Xiaohui; Shen, Xuemin; Lin, Xiaodong; Luo, Henry Y

    2014-03-01

    In this paper, we propose an e-health monitoring system with minimum service delay and privacy preservation by exploiting geo-distributed clouds. In the system, the resource allocation scheme enables the distributed cloud servers to cooperatively assign the servers to the requested users under the load balance condition. Thus, the service delay for users is minimized. In addition, a traffic-shaping algorithm is proposed. The traffic-shaping algorithm converts the user health data traffic to the nonhealth data traffic such that the capability of traffic analysis attacks is largely reduced. Through the numerical analysis, we show the efficiency of the proposed traffic-shaping algorithm in terms of service delay and privacy preservation. Furthermore, through the simulations, we demonstrate that the proposed resource allocation scheme significantly reduces the service delay compared to two other alternatives using jointly the short queue and distributed control law.

  9. The seismic traffic footprint: Tracking trains, aircraft, and cars seismically

    NASA Astrophysics Data System (ADS)

    Riahi, Nima; Gerstoft, Peter

    2015-04-01

    Although naturally occurring vibrations have proven useful to probe the subsurface, the vibrations caused by traffic have not been explored much. Such data, however, are less sensitive to weather and low visibility compared to some common out-of-road traffic sensing systems. We study traffic-generated seismic noise measured by an array of 5200 geophones that covered a 7 × 10 km area in Long Beach (California, USA) with a receiver spacing of 100 m. This allows us to look into urban vibrations below the resolution of a typical city block. The spatiotemporal structure of the anthropogenic seismic noise intensity reveals the Blue Line Metro train activity, departing and landing aircraft in Long Beach Airport and their acceleration, and gives clues about traffic movement along the I-405 highway at night. As low-cost, stand-alone seismic sensors are becoming more common, these findings indicate that seismic data may be useful for traffic monitoring.

  10. Design/build vs traditional construction user delay modeling : an evaluation of the cost effectiveness of innovative construction methods for new construction. Part 2 : VISUM Online for Salt Lake, Davis, and Utah Counties

    DOT National Transportation Integrated Search

    2007-05-01

    VISUM Online is a traffic management system for processing online traffic data. The system implements both a road network model and a traffic demand model. VISUM Online uses all available real-time and historic data to calculate current and forecaste...

  11. Temporal variation of traffic on highways and the development of accurate temporal allocation factors for air pollution analyses

    NASA Astrophysics Data System (ADS)

    Batterman, Stuart; Cook, Richard; Justin, Thomas

    2015-04-01

    Traffic activity encompasses the number, mix, speed and acceleration of vehicles on roadways. The temporal pattern and variation of traffic activity reflects vehicle use, congestion and safety issues, and it represents a major influence on emissions and concentrations of traffic-related air pollutants. Accurate characterization of vehicle flows is critical in analyzing and modeling urban and local-scale pollutants, especially in near-road environments and traffic corridors. This study describes methods to improve the characterization of temporal variation of traffic activity. Annual, monthly, daily and hourly temporal allocation factors (TAFs), which describe the expected temporal variation in traffic activity, were developed using four years of hourly traffic activity data recorded at 14 continuous counting stations across the Detroit, Michigan, U.S. region. Five sites also provided vehicle classification. TAF-based models provide a simple means to apportion annual average estimates of traffic volume to hourly estimates. The analysis shows the need to separate TAFs for total and commercial vehicles, and weekdays, Saturdays, Sundays and observed holidays. Using either site-specific or urban-wide TAFs, nearly all of the variation in historical traffic activity at the street scale could be explained; unexplained variation was attributed to adverse weather, traffic accidents and construction. The methods and results presented in this paper can improve air quality dispersion modeling of mobile sources, and can be used to evaluate and model temporal variation in ambient air quality monitoring data and exposure estimates.

  12. Temporal variation of traffic on highways and the development of accurate temporal allocation factors for air pollution analyses

    PubMed Central

    Batterman, Stuart; Cook, Richard; Justin, Thomas

    2015-01-01

    Traffic activity encompasses the number, mix, speed and acceleration of vehicles on roadways. The temporal pattern and variation of traffic activity reflects vehicle use, congestion and safety issues, and it represents a major influence on emissions and concentrations of traffic-related air pollutants. Accurate characterization of vehicle flows is critical in analyzing and modeling urban and local-scale pollutants, especially in near-road environments and traffic corridors. This study describes methods to improve the characterization of temporal variation of traffic activity. Annual, monthly, daily and hourly temporal allocation factors (TAFs), which describe the expected temporal variation in traffic activity, were developed using four years of hourly traffic activity data recorded at 14 continuous counting stations across the Detroit, Michigan, U.S. region. Five sites also provided vehicle classification. TAF-based models provide a simple means to apportion annual average estimates of traffic volume to hourly estimates. The analysis shows the need to separate TAFs for total and commercial vehicles, and weekdays, Saturdays, Sundays and observed holidays. Using either site-specific or urban-wide TAFs, nearly all of the variation in historical traffic activity at the street scale could be explained; unexplained variation was attributed to adverse weather, traffic accidents and construction. The methods and results presented in this paper can improve air quality dispersion modeling of mobile sources, and can be used to evaluate and model temporal variation in ambient air quality monitoring data and exposure estimates. PMID:25844042

  13. Phase diagram of congested traffic flow: An empirical study

    PubMed

    Lee; Lee; Kim

    2000-10-01

    We analyze traffic data from a highway section containing one effective on-ramp. Based on two criteria, local velocity variation patterns and expansion (or nonexpansion) of congested regions, three distinct congested traffic states are identified. These states appear at different levels of the upstream flux and the on-ramp flux, thereby generating a phase digram of the congested traffic flow. Observed traffic states are compared with recent theoretical analyses and both agreeing and disagreeing features are found.

  14. Impact of traffic oscillations on freeway crash occurrences.

    PubMed

    Zheng, Zuduo; Ahn, Soyoung; Monsere, Christopher M

    2010-03-01

    Traffic oscillations are typical features of congested traffic flow that are characterized by recurring decelerations followed by accelerations (stop-and-go driving). The negative environmental impacts of these oscillations are widely accepted, but their impact on traffic safety has been debated. This paper describes the impact of freeway traffic oscillations on traffic safety. This study employs a matched case-control design using high-resolution traffic and crash data from a freeway segment. Traffic conditions prior to each crash were taken as cases, while traffic conditions during the same periods on days without crashes were taken as controls. These were also matched by presence of congestion, geometry and weather. A total of 82 cases and about 80,000 candidate controls were extracted from more than three years of data from 2004 to 2007. Conditional logistic regression models were developed based on the case-control samples. To verify consistency in the results, 20 different sets of controls were randomly extracted from the candidate pool for varying control-case ratios. The results reveal that the standard deviation of speed (thus, oscillations) is a significant variable, with an average odds ratio of about 1.08. This implies that the likelihood of a (rear-end) crash increases by about 8% with an additional unit increase in the standard deviation of speed. The average traffic states prior to crashes were less significant than the speed variations in congestion. Published by Elsevier Ltd.

  15. Surveying traffic congestion based on the concept of community structure of complex networks

    NASA Astrophysics Data System (ADS)

    Ma, Lili; Zhang, Zhanli; Li, Meng

    2016-07-01

    In this paper, taking the traffic of Beijing city as an instance, we study city traffic states, especially traffic congestion, based on the concept of network community structure. Concretely, using the floating car data (FCD) information of vehicles gained from the intelligent transport system (ITS) of the city, we construct a new traffic network model which is with floating cars as network nodes and time-varying. It shows that this traffic network has Gaussian degree distributions at different time points. Furthermore, compared with free traffic situations, our simulations show that the traffic network generally has more obvious community structures with larger values of network fitness for congested traffic situations, and through the GPSspg web page, we show that all of our results are consistent with the reality. Then, it indicates that network community structure should be an available way for investigating city traffic congestion problems.

  16. Impacts of freeway traffic conditions on in-vehicle exposure to ultrafine particulate matter

    NASA Astrophysics Data System (ADS)

    Bigazzi, Alexander Y.; Figliozzi, Miguel A.

    2012-12-01

    There is evidence of adverse health impacts from human exposure to traffic-related ultrafine particulate matter pollution. As more commuters are spending a significant portion of their daily routine inside vehicles, it is increasingly relevant to study exposure levels to harmful pollutants inside the vehicle microenvironment. This study is one of the first research efforts to combine detailed freeway traffic data (at 20 s intervals) and in-vehicle ultrafine particulate (UFP) exposure data under varying vehicle ventilation conditions. Results show that due to negative correlation between traffic speed and density, traffic states have a small but significant impact on in-vehicle UFP concentrations, highest in high traffic flow-high speed conditions or in high traffic density-low speed conditions. Vehicle cabin barrier effects are the primary determinant of in-vehicle exposure concentrations, providing 15% protection with the windows down, 47% protection with the windows up and the vent open, and 83-90% protection with the windows up and the vent closed (more with the air conditioning on). Unique results from this study include the dominance of ventilation over traffic effects on UFP and the non-linear relationships between traffic variables and UFP concentrations. The results of this research have important implications for exposure modeling and potential exposure mitigation strategies.

  17. Gis-Based Route Finding Using ANT Colony Optimization and Urban Traffic Data from Different Sources

    NASA Astrophysics Data System (ADS)

    Davoodi, M.; Mesgari, M. S.

    2015-12-01

    Nowadays traffic data is obtained from multiple sources including GPS, Video Vehicle Detectors (VVD), Automatic Number Plate Recognition (ANPR), Floating Car Data (FCD), VANETs, etc. All such data can be used for route finding. This paper proposes a model for finding the optimum route based on the integration of traffic data from different sources. Ant Colony Optimization is applied in this paper because the concept of this method (movement of ants in a network) is similar to urban road network and movements of cars. The results indicate that this model is capable of incorporating data from different sources, which may even be inconsistent.

  18. Automatic Data Traffic Control on DSM Architecture

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Jin, Hao-Qiang; Yan, Jerry; Kwak, Dochan (Technical Monitor)

    2000-01-01

    We study data traffic on distributed shared memory machines and conclude that data placement and grouping improve performance of scientific codes. We present several methods which user can employ to improve data traffic in his code. We report on implementation of a tool which detects the code fragments causing data congestions and advises user on improvements of data routing in these fragments. The capabilities of the tool include deduction of data alignment and affinity from the source code; detection of the code constructs having abnormally high cache or TLB misses; generation of data placement constructs. We demonstrate the capabilities of the tool on experiments with NAS parallel benchmarks and with a simple computational fluid dynamics application ARC3D.

  19. ITS traffic data consolidation system

    DOT National Transportation Integrated Search

    2005-03-01

    The Arizona Department of Transportation (ADOT) maintains a variety of independent applications to monitor roadway : conditions and activities across the state including traffic counts, weather data, signal timing, Variable Message Sign (VMS) : advis...

  20. Bayes classifiers for imbalanced traffic accidents datasets.

    PubMed

    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.

  1. Air Traffic Sector Configuration Change Frequency

    NASA Technical Reports Server (NTRS)

    Chatterji, Gano Broto; Drew, Michael

    2009-01-01

    Several techniques for partitioning airspace have been developed in the literature. The question of whether a region of airspace created by such methods can be used with other days of traffic, and the number of times a different partition is needed during the day is examined in this paper. Both these aspects are examined for the Fort Worth Center airspace sectors. A Mixed Integer Linear Programming method is used with actual air traffic data of ten high-volume low-weather-delay days for creating sectors. Nine solutions were obtained for each two-hour period of the day by partitioning the center airspace into two through 18 sectors in steps of two sectors. Actual track-data were played back with the generated partitions for creating histograms of the traffic-counts. The best partition for each two-hour period was then identified based on the nine traffic-count distributions. Numbers of sectors in such partitions were analyzed to determine the number of times a different configuration is needed during the day. One to three partitions were selected for the 24-hour period, and traffic data from ten days were played back to test if the traffic-counts stayed below the threshold values associated with these partitions. Results show that these partitions are robust and can be used for longer durations than they were designed for

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

    PubMed

    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.

  3. Throughput analysis of the IEEE 802.4 token bus standard under heavy load

    NASA Technical Reports Server (NTRS)

    Pang, Joseph; Tobagi, Fouad

    1987-01-01

    It has become clear in the last few years that there is a trend towards integrated digital services. Parallel to the development of public Integrated Services Digital Network (ISDN) is service integration in the local area (e.g., a campus, a building, an aircraft). The types of services to be integrated depend very much on the specific local environment. However, applications tend to generate data traffic belonging to one of two classes. According to IEEE 802.4 terminology, the first major class of traffic is termed synchronous, such as packetized voice and data generated from other applications with real-time constraints, and the second class is called asynchronous which includes most computer data traffic such as file transfer or facsimile. The IEEE 802.4 token bus protocol which was designed to support both synchronous and asynchronous traffic is examined. The protocol is basically a timer-controlled token bus access scheme. By a suitable choice of the design parameters, it can be shown that access delay is bounded for synchronous traffic. As well, the bandwidth allocated to asynchronous traffic can be controlled. A throughput analysis of the protocol under heavy load with constant channel occupation of synchronous traffic and constant token-passing times is presented.

  4. Multifunction Data Link for an Advanced Air-Traffic Management System

    DOT National Transportation Integrated Search

    1972-11-01

    This report evaluates the requirements relating to a multi-function data link for an advanced Air Traffic Management System. A two-way time ordered data link is postulated to accomplish the communication and control function. Several candidate modula...

  5. Operational evaluation of initial data link air traffic control services, Vol. 1

    DOT National Transportation Integrated Search

    1990-02-01

    This report details the results of an operational evaluation of Initial Data Link Air Traffic Control (ATC) Services. The Operational Evaluation was conducted at the Federal Aviation Administration (FAA) Technical Center utilizing the Data Link test ...

  6. Test Results of Initial Installation DATAS/TCAS Monitor: DFW Airport

    DOT National Transportation Integrated Search

    1992-01-01

    This document presents the results of initial tests with the Data Link Test and : Analysis System (DATAS)/Traffic Alert and Collision Avoidance System (TCAS). : Since a significant amount of air carriers have recently been equipped with : Traffic Ale...

  7. Operational evaluation of initial data link air traffic control services, Vol. 2 - Appendixes

    DOT National Transportation Integrated Search

    1990-02-01

    This report details the results of an operational evaluation of Initial Data : LInk Air Traffic Control (ATC) Services. The Operational Evaluation was : conducted at the Federal Aviation Administration (FAA)Technical Center utilizing : the Data Link ...

  8. Traffic Tech: National Traffic Speeds Survey III: 2015

    DOT National Transportation Integrated Search

    2018-03-01

    Vehicle speeds are an important factor in traffic safety. NHTSAs most recent data estimates that approximately 27 percent of all fatal motor vehicle crashes are speeding-related (NCSA, 2018). NHTSA estimated the economic cost of speeding-related c...

  9. FHWA traffic noise model, version 1.0 : user's guide

    DOT National Transportation Integrated Search

    1998-01-01

    This User's Guide is for the Federal Highway Administration's Traffic Noise Model (FHWA TNM), Version 1.0 -- the FHWAs computer program for highway traffic noise prediction and analysis. Two companion reports, a Technical Manual and a data repor...

  10. Symbols for cockpit displays of traffic information

    DOT National Transportation Integrated Search

    2009-10-25

    A web-based study assessed pilots ability to learn and remember traffic symbols that may be shown on a Cockpit Display of Traffic Information (CDTI). These displays convey data obtained from Automatic Dependent Surveillance-Broadcast (ADS B) and rela...

  11. Using Mobile Device Samples to Estimate Traffic Volumes

    DOT National Transportation Integrated Search

    2017-12-01

    In this project, TTI worked with StreetLight Data to evaluate a beta version of its traffic volume estimates derived from global positioning system (GPS)-based mobile devices. TTI evaluated the accuracy of average annual daily traffic (AADT) volume :...

  12. FHWA Traffic Noise Model, version 1.0 technical manual

    DOT National Transportation Integrated Search

    1998-02-01

    This Technical Manual is for the Federal Highway Administrations Traffic Noise Model (FHWA TNM), Version 1.0 -- the FHWAs computer program for highway traffic noise prediction and analysis. Two companion reports, a Users Guide and a data r...

  13. Cellular automata model for use with real freeway data

    DOT National Transportation Integrated Search

    2002-01-01

    The exponential rate of increase in freeway traffic is expanding the need for accurate and : realistic methods to model and predict traffic flow. Traffic modeling and simulation facilitates an : examination of both microscopic and macroscopic views o...

  14. Traffic Surveillance Data Processing in Urban Freeway Corridors Using Kalman Filter Techniques

    DOT National Transportation Integrated Search

    1978-11-01

    Real-time surveillance of traffic conditions on urban freeway corridors using spatially discrete presence detectors is addressed. Using a finite-dimensional (macroscopic) fluid-analog model for freeway vehicular traffic flow, an extended Kalman filte...

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

    DOT National Transportation Integrated Search

    2012-05-01

    New traffic sensing devices based on wireless sensing technologies were designed and tested. Such devices encompass a cost-effective, battery-free, and energy self-sustained architecture for real-time traffic measurement over distributed points in a ...

  16. Symbols for cockpit displays of traffic information

    DOT National Transportation Integrated Search

    2010-03-01

    A web-based study assessed pilots ability to learn and remember traffic symbols that may be shown on a Cockpit Display of Traffic Information (CDTI). These displays convey data obtained from Automatic Dependent Surveillance-Broadcast (ADS B) and rela...

  17. Traffic flow simulation for an urban freeway corridor

    DOT National Transportation Integrated Search

    1998-01-01

    The objective of this paper is to develop a realistic and operational macroscopic traffic flow simulation model which requires relatively less data collection efforts. Such a model should be capable of delineating the dynamics of traffic flow created...

  18. Active traffic management case study: phase 1 : final report.

    DOT National Transportation Integrated Search

    2016-03-01

    This study developed a systematic approach for using data from multiple sources to provide active traffic management : solutions. The feasibility of two active traffic management solutions is analyzed in this report: ramp-metering and real-time : cra...

  19. Geographic Information System (GIS) capabilities in traffic accident information management: a qualitative approach.

    PubMed

    Ahmadi, Maryam; Valinejadi, Ali; Goodarzi, Afshin; Safari, Ameneh; Hemmat, Morteza; Majdabadi, Hesamedin Askari; Mohammadi, Ali

    2017-06-01

    Traffic accidents are one of the more important national and international issues, and their consequences are important for the political, economical, and social level in a country. Management of traffic accident information requires information systems with analytical and accessibility capabilities to spatial and descriptive data. The aim of this study was to determine the capabilities of a Geographic Information System (GIS) in management of traffic accident information. This qualitative cross-sectional study was performed in 2016. In the first step, GIS capabilities were identified via literature retrieved from the Internet and based on the included criteria. Review of the literature was performed until data saturation was reached; a form was used to extract the capabilities. In the second step, study population were hospital managers, police, emergency, statisticians, and IT experts in trauma, emergency and police centers. Sampling was purposive. Data was collected using a questionnaire based on the first step data; validity and reliability were determined by content validity and Cronbach's alpha of 75%. Data was analyzed using the decision Delphi technique. GIS capabilities were identified in ten categories and 64 sub-categories. Import and process of spatial and descriptive data and so, analysis of this data were the most important capabilities of GIS in traffic accident information management. Storing and retrieving of descriptive and spatial data, providing statistical analysis in table, chart and zoning format, management of bad structure issues, determining the cost effectiveness of the decisions and prioritizing their implementation were the most important capabilities of GIS which can be efficient in the management of traffic accident information.

  20. Traffic Management for Satellite-ATM Networks

    NASA Technical Reports Server (NTRS)

    Goyal, Rohit; Jain, Raj; Fahmy, Sonia; Vandalore, Bobby; Goyal, Mukul

    1998-01-01

    Various issues associated with "Traffic Management for Satellite-ATM Networks" are presented in viewgraph form. Specific topics include: 1) Traffic management issues for TCP/IP based data services over satellite-ATM networks; 2) Design issues for TCP/IP over ATM; 3) Optimization of the performance of TCP/IP over ATM for long delay networks; and 4) Evaluation of ATM service categories for TCP/IP traffic.

  1. Evaluation of Traffic Density Parameters as an Indicator of Vehicle Emission-Related Near-Road Air Pollution: A Case Study with NEXUS Measurement Data on Black Carbon

    EPA Science Inventory

    An important factor in evaluating health risk of near-road air pollution is to accurately estimate the traffic-related vehicle emission of air pollutants. Inclusion of traffic parameters such as road length/area, distance to roads, and traffic volume/intensity into models such as...

  2. Bag-of-visual-phrases and hierarchical deep models for traffic sign detection and recognition in mobile laser scanning data

    NASA Astrophysics Data System (ADS)

    Yu, Yongtao; Li, Jonathan; Wen, Chenglu; Guan, Haiyan; Luo, Huan; Wang, Cheng

    2016-03-01

    This paper presents a novel algorithm for detection and recognition of traffic signs in mobile laser scanning (MLS) data for intelligent transportation-related applications. The traffic sign detection task is accomplished based on 3-D point clouds by using bag-of-visual-phrases representations; whereas the recognition task is achieved based on 2-D images by using a Gaussian-Bernoulli deep Boltzmann machine-based hierarchical classifier. To exploit high-order feature encodings of feature regions, a deep Boltzmann machine-based feature encoder is constructed. For detecting traffic signs in 3-D point clouds, the proposed algorithm achieves an average recall, precision, quality, and F-score of 0.956, 0.946, 0.907, and 0.951, respectively, on the four selected MLS datasets. For on-image traffic sign recognition, a recognition accuracy of 97.54% is achieved by using the proposed hierarchical classifier. Comparative studies with the existing traffic sign detection and recognition methods demonstrate that our algorithm obtains promising, reliable, and high performance in both detecting traffic signs in 3-D point clouds and recognizing traffic signs on 2-D images.

  3. Modeling the frequency of opposing left-turn conflicts at signalized intersections using generalized linear regression models.

    PubMed

    Zhang, Xin; Liu, Pan; Chen, Yuguang; Bai, Lu; Wang, Wei

    2014-01-01

    The primary objective of this study was to identify whether the frequency of traffic conflicts at signalized intersections can be modeled. The opposing left-turn conflicts were selected for the development of conflict predictive models. Using data collected at 30 approaches at 20 signalized intersections, the underlying distributions of the conflicts under different traffic conditions were examined. Different conflict-predictive models were developed to relate the frequency of opposing left-turn conflicts to various explanatory variables. The models considered include a linear regression model, a negative binomial model, and separate models developed for four traffic scenarios. The prediction performance of different models was compared. The frequency of traffic conflicts follows a negative binominal distribution. The linear regression model is not appropriate for the conflict frequency data. In addition, drivers behaved differently under different traffic conditions. Accordingly, the effects of conflicting traffic volumes on conflict frequency vary across different traffic conditions. The occurrences of traffic conflicts at signalized intersections can be modeled using generalized linear regression models. The use of conflict predictive models has potential to expand the uses of surrogate safety measures in safety estimation and evaluation.

  4. Design of a rotary for an uncontrolled multi-leg intersection in Chennai, India

    NASA Astrophysics Data System (ADS)

    Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam

    2017-11-01

    One way to control the traffic at busy intersections is to construct a roundabout or rotary intersection, which is a special type of at-grade intersection, where all converging vehicles are forced to move round a central island in clock-wise direction. The present study aims to design a rotary for an uncontrolled multi leg intersection located in Royapetah in Chennai, India. The intersection has five approach roads with two-way traffic in all the approach roads and there is no signal or traffic police to control the traffic at present and hence experiences traffic chaos during peak hours. In order to design the rotary, it is essential to have the information on traffic volumes coming from the approach roads. For this, a video data collection was carried out for a duration of eight hours from 7.30 am to 11.30 am and from 2.30 pm to 6.30 pm on a typical working day using a handycam from the terrace of an apartment building located near the intersection. During data extraction stage, each 5 min. traffic volume was extracted for all the five classes of vehicles considered and were converted to passenger car units (PCU). The analysis of traffic data showed that during peak hour from 4.45 pm to 5.45 pm, the proportion of weaving traffic, i.e., ratio of sum of crossing streams to the total traffic on the weaving section was found to be 0.81. According to Indian road congress (IRC) guidelines, this proportion can take any value between 0.4 and 1 and in the present study, the calculated value is found to be within the prescribed range. Using the calculated values of average entry width of the rotary and width & length of weaving section, the practical capacity of the rotary was found to be 3020 PCUs which is well above the observed traffic volume of 2665 PCUs.

  5. Oceanic Situational Awareness over the North Atlantic Corridor

    NASA Technical Reports Server (NTRS)

    Welch, Bryan; Greenfield, Israel

    2005-01-01

    Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the oceanic domain. The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the North Atlantic Corridor to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

  6. Oceanic Situational Awareness Over the Pacific Corridor

    NASA Technical Reports Server (NTRS)

    Welch, Bryan; Greenfeld, Israel

    2005-01-01

    Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the Pacific Ocean. The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the Pacific Corridor to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

  7. Oceanic Situational Awareness Over the Gulf of Mexico

    NASA Technical Reports Server (NTRS)

    Welch, Bryan; Greenfeld, Israel

    2005-01-01

    Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the Gulf of Mexico. The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the Gulf of Mexico to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

  8. Economical Video Monitoring of Traffic

    NASA Technical Reports Server (NTRS)

    Houser, B. C.; Paine, G.; Rubenstein, L. D.; Parham, O. Bruce, Jr.; Graves, W.; Bradley, C.

    1986-01-01

    Data compression allows video signals to be transmitted economically on telephone circuits. Telephone lines transmit television signals to remote traffic-control center. Lines also carry command signals from center to TV camera and compressor at highway site. Video system with television cameras positioned at critical points on highways allows traffic controllers to determine visually, almost immediately, exact cause of traffic-flow disruption; e.g., accidents, breakdowns, or spills, almost immediately. Controllers can then dispatch appropriate emergency services and alert motorists to minimize traffic backups.

  9. Indicators of residential traffic exposure: Modelled NOX, traffic proximity, and self-reported exposure in RHINE III

    NASA Astrophysics Data System (ADS)

    Carlsen, Hanne Krage; Bäck, Erik; Eneroth, Kristina; Gislason, Thorarinn; Holm, Mathias; Janson, Christer; Jensen, Steen Solvang; Johannessen, Ane; Kaasik, Marko; Modig, Lars; Segersson, David; Sigsgaard, Torben; Forsberg, Bertil; Olsson, David; Orru, Hans

    2017-10-01

    Few studies have investigated associations between self-reported and modelled exposure to traffic pollution. The objective of this study was to examine correlations between self-reported traffic exposure and modelled (a) NOX and (b) traffic proximity in seven different northern European cities; Aarhus (Denmark), Bergen (Norway), Gothenburg, Umeå, and Uppsala (Sweden), Reykjavik (Iceland), and Tartu (Estonia). We analysed data from the RHINE III (Respiratory Health in Northern Europe, http://www.rhine.nu)

  10. Application research on temporal GIS in the transportation information management system

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Qin, Qianqing; Wang, Chao

    2006-10-01

    The application, development and key matters of applying spatio-temporal GIS to traffic information management system are discussed in this paper by introducing the development of spatio-temporal database, current models of spatio-temporal data, traits of traffic information management system. This paper proposes a method of organizing spatio-temporal data taking road object changes into consideration, and describes its data structure in 3 aspects, including structure of spatio-temporal object, organizing method spatio-temporal data and storage means of spatio-temporal data. Trying to manage types of spatio-temporal data involved in traffic system, such as road information, river information, railway information, social and economical data, and etc, uniformly, efficiently and with low redundancy.

  11. Integrating Emerging Data Sources Into Operational Practice

    DOT National Transportation Integrated Search

    2018-05-15

    Agencies have the potential to collect, use, and share data from connected and automated vehicles (CAV), connected travelers, and connected infrastructure elements to improve the performance of their traffic management systems and traffic management ...

  12. 2007 Louisiana traffic records data report

    DOT National Transportation Integrated Search

    2008-01-01

    The 2007 LOUISIANA TRAFFIC RECORDS DATA REPORT indicates the following : occurrence rates for 2007: : 895 fatal crashes : 987 fatalities : 78.9 thousand injuries : 110.6 thousand property-damage-only crashes : These crashes resulted i...

  13. 2008 Louisiana traffic records data report

    DOT National Transportation Integrated Search

    2009-01-01

    The 2008 LOUISIANA TRAFFIC RECORDS DATA REPORT indicates the following : occurrence rates for 2008: : 818 fatal crashes : 913 fatalities : 75.9 thousand injuries : 110.6 thousand property-damage-only crashes : These crashes resulted i...

  14. 2006 Louisiana traffic records data report

    DOT National Transportation Integrated Search

    2007-01-01

    The 2006 LOUISIANA TRAFFIC RECORDS DATA REPORT indicates the following : occurrence rates for 2006: : 889 fatal crashes : 985 fatalities : 79.9 thousand injuries : 112.3 thousand property-damage-only crashes : These crashes resulted i...

  15. Demonstration of alternative traffic information collection and management technologies

    NASA Astrophysics Data System (ADS)

    Knee, Helmut E.; Smith, Cy; Black, George; Petrolino, Joe

    2004-03-01

    Many of the components associated with the deployment of Intelligent Transportation Systems (ITS) to support a traffic management center (TMC) such as remote control cameras, traffic speed detectors, and variable message signs, have been available for many years. Their deployment, however, has been expensive and applied primarily to freeways and interstates, and have been deployed principally in the major metropolitan areas in the US; not smaller cities. The Knoxville (Tennessee) Transportation Planning Organization is sponsoring a project that will test the integration of several technologies to estimate near-real time traffic information data and information that could eventually be used by travelers to make better and more informed decisions related to their travel needs. The uniqueness of this demonstration is that it will seek to predict traffic conditions based on cellular phone signals already being collected by cellular communications companies. Information about the average speed on various portions of local arterials and incident identification (incident location) will be collected and compared to similar data generated by "probe vehicles". Successful validation of the speed information generated from cell phone data will allow traffic data to be generated much more economically and utilize technologies that are minimally infrastructure invasive. Furthermore, when validated, traffic information could be provided to the traveling public allowing then to make better decisions about trips. More efficient trip planning and execution can reduce congestion and associated vehicle emissions. This paper will discuss the technologies, the demonstration project, the project details, and future directions.

  16. Performance measures for freight & general traffic : investigating similarities and differences using alternate data sources.

    DOT National Transportation Integrated Search

    2015-06-01

    Recent advances in probe vehicle data collection systems have enabled monitoring traffic : conditions at finer temporal and spatial resolution. The primary objective of the current study is : to leverage these probe data sources to understand if ther...

  17. Summary for 1996 LTPP traffic data collection : annual summary.

    DOT National Transportation Integrated Search

    1997-06-01

    In 1996 the Research Unit continued to collect traffic data for the Long Term Pavement Performance Program, hereinafter referred to as the LTPP program. The LTPP program is essentially comprised of on-site computers that apply collected data to an al...

  18. Development of a Computational Framework for Big Data-Driven Prediction of Long-Term Bridge Performance and Traffic Flow

    DOT National Transportation Integrated Search

    2018-04-01

    Consistent efforts with dense sensor deployment and data gathering processes for bridge big data have accumulated profound information regarding bridge performance, associated environments, and traffic flows. However, direct applications of bridge bi...

  19. Correlation Analysis of Freeway Traffic Status and Crashes with Nevada Data.

    DOT National Transportation Integrated Search

    2017-11-11

    This project is to study the correlation between freeway traffic status and crash risks with the historical freeway ITS data and related crash data in Nevada. With the comprehensive review of previous research results, the Center for Advanced Transpo...

  20. Computers in Traffic Education.

    ERIC Educational Resources Information Center

    Alexander, O. P.

    1983-01-01

    Traffic education covers basic road skills, legal/insurance aspects, highway code, accident causation/prevention, and vehicle maintenance. Microcomputer applications to traffic education are outlined, followed by a selected example of programs currently available (focusing on drill/practice, simulation, problem-solving, data manipulation, games,…

  1. Decision support tools to support the operations of traffic management centers (TMC)

    DOT National Transportation Integrated Search

    2011-01-31

    The goal of this project is to develop decision support tools to support traffic management operations based on collected intelligent transportation system (ITS) data. The project developments are in accordance with the needs of traffic management ce...

  2. Improving the effectiveness of traffic monitoring based on wireless location technology.

    DOT National Transportation Integrated Search

    2004-01-01

    A fundamental requirement for effectively monitoring and operating transportation facilities is reliable, accurate data on traffic flow. The current state of the practice is to use networks of point detectors to gather information on traffic flow at ...

  3. Quantifying incident-induced travel delays on freeways using traffic sensor data

    DOT National Transportation Integrated Search

    2008-02-01

    Traffic congestion is a major operational problem for freeways in Washington State. Recent studies have estimated that more than 50% of freeway congestion is caused by traffic incidents. To help the Washington State Department of Transportation (WSDO...

  4. Quantifying incident-induced travel delays on freeways using traffic sensor data

    DOT National Transportation Integrated Search

    2008-05-01

    Traffic congestion is a major operational problem for freeways in Washington State. Recent studies have estimated that more than 50 percent of freeway congestion is caused by traffic incidents. To help the Washington State Department of Transportatio...

  5. Variability in traffic monitoring data : final summary report

    DOT National Transportation Integrated Search

    1997-08-01

    For highway maintenance and planning purposes, each road segment is characterized by its traffic flow [such as the annual average daily traffic (AADT) and the AADT for each vehicle class], by the weight distribution of vehicles that travel on its roa...

  6. First Coast Guard district traffic model report

    DOT National Transportation Integrated Search

    1997-11-01

    The purpose of this report was to describe the methodology used in developing the First Coast Guard District (CGD1) Traffic Model and to document the potential National Distress System (NDS) voice and data traffic forecasted for the year 2001. The ND...

  7. Analysis of Child-related Road Traffic Accidents in Vietnam

    NASA Astrophysics Data System (ADS)

    Vu, Anh Tuan; Nguyen, Dinh Vinh Man

    2018-04-01

    In recent years, the number of road traffic accidents, fatalities and injuries have been decreasing, but the figures of children road traffic accidents have been increasing in Ho Chi Minh City of Vietnam. This fact strongly calls for implementing effective solutions to improve traffic safety for children by the local government. This paper presents the trends, patterns and causes of road traffic accidents involving children based on the analysis of road traffic accident data over the period 2010-2015 and the video-based observations of road traffic law violations at 15 typical school gates and 10 typical roads. The results could be useful for the city government to formulate solutions to effectively improve traffic safety for children in Ho Chi Minh City and other cities in Vietnam.

  8. Data Mining for Understanding and Impriving Decision-Making Affecting Ground Delay Programs

    NASA Technical Reports Server (NTRS)

    Kulkarni, Deepak; Wang, Yao Xun; Sridhar, Banavar

    2013-01-01

    The continuous growth in the demand for air transportation results in an imbalance between airspace capacity and traffic demand. The airspace capacity of a region depends on the ability of the system to maintain safe separation between aircraft in the region. In addition to growing demand, the airspace capacity is severely limited by convective weather. During such conditions, traffic managers at the FAA's Air Traffic Control System Command Center (ATCSCC) and dispatchers at various Airlines' Operations Center (AOC) collaborate to mitigate the demand-capacity imbalance caused by weather. The end result is the implementation of a set of Traffic Flow Management (TFM) initiatives such as ground delay programs, reroute advisories, flow metering, and ground stops. Data Mining is the automated process of analyzing large sets of data and then extracting patterns in the data. Data mining tools are capable of predicting behaviors and future trends, allowing an organization to benefit from past experience in making knowledge-driven decisions. The work reported in this paper is focused on ground delay programs. Data mining algorithms have the potential to develop associations between weather patterns and the corresponding ground delay program responses. If successful, they can be used to improve and standardize TFM decision resulting in better predictability of traffic flows on days with reliable weather forecasts. The approach here seeks to develop a set of data mining and machine learning models and apply them to historical archives of weather observations and forecasts and TFM initiatives to determine the extent to which the theory can predict and explain the observed traffic flow behaviors.

  9. Suitability of Synthetic Driving Profiles from Traffic Micro-Simulation for Real-World Energy Analysis: Preprint

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

    Hou, Yunfei; Wood, Eric; Burton, Evan

    A shift towards increased levels of driving automation is generally expected to result in improved safety and traffic congestion outcomes. However, little empirical data exists to estimate the impact that automated driving could have on energy consumption and greenhouse gas emissions. In the absence of empirical data on differences between drive cycles from present day vehicles (primarily operated by humans) and future vehicles (partially or fully operated by computers) one approach is to model both situations over identical traffic conditions. Such an exercise requires traffic micro-simulation to not only accurately model vehicle operation under high levels of automation, but alsomore » (and potentially more challenging) vehicle operation under present day human drivers. This work seeks to quantify the ability of a commercial traffic micro-simulation program to accurately model real-world drive cycles in vehicles operated primarily by humans in terms of driving speed, acceleration, and simulated fuel economy. Synthetic profiles from models of freeway and arterial facilities near Atlanta, Georgia, are compared to empirical data collected from real-world drivers on the same facilities. Empirical and synthetic drive cycles are then simulated in a powertrain efficiency model to enable comparison on the basis of fuel economy. Synthetic profiles from traffic micro-simulation were found to exhibit low levels of transient behavior relative to the empirical data. Even with these differences, the synthetic and empirical data in this study agree well in terms of driving speed and simulated fuel economy. The differences in transient behavior between simulated and empirical data suggest that larger stochastic contributions in traffic micro-simulation (relative to those present in the traffic micro-simulation tool used in this study) are required to fully capture the arbitrary elements of human driving. Interestingly, the lack of stochastic contributions from models of human drivers in this study did not result in a significant discrepancy between fuel economy simulations based on synthetic and empirical data; a finding with implications on the potential energy efficiency gains of automated vehicle technology.« less

  10. Does Temperature Modify the Effects of Rain and Snow Precipitation on Road Traffic Injuries?

    PubMed

    Lee, Won-Kyung; Lee, Hye-Ah; Hwang, Seung-sik; Kim, Ho; Lim, Youn-Hee; Hong, Yun-Chul; Ha, Eun-Hee; Park, Hyesook

    2015-01-01

    There are few data on the interaction between temperature and snow and rain precipitation, although they could interact in their effects on road traffic injuries. The integrated database of the Korea Road Traffic Authority was used to calculate the daily frequency of road traffic injuries in Seoul. Weather data included rain and snow precipitation, temperature, pressure, and fog from May 2007 to December 2011. Precipitation of rain and snow were divided into nine and six temperature range categories, respectively. The interactive effects of temperature and rain and snow precipitation on road traffic injuries were analyzed using a generalized additive model with a Poisson distribution. The risk of road traffic injuries during snow increased when the temperature was below freezing. Road traffic injuries increased by 6.6% when it was snowing and above 0 °C, whereas they increased by 15% when it was snowing and at or below 0 °C. In terms of heavy rain precipitation, moderate temperatures were related to an increased prevalence of injuries. When the temperature was 0-20 °C, we found a 12% increase in road traffic injuries, whereas it increased by 8.5% and 6.8% when it was <0 °C and >20 °C, respectively. The interactive effect was consistent across the traffic accident subtypes. The effect of adverse weather conditions on road traffic injuries differed depending on the temperature. More road traffic injuries were related to rain precipitation when the temperature was moderate and to snow when it was below freezing.

  11. Does Temperature Modify the Effects of Rain and Snow Precipitation on Road Traffic Injuries?

    PubMed Central

    Lee, Won-Kyung; Lee, Hye-Ah; Hwang, Seung-sik; Kim, Ho; Lim, Youn-Hee; Hong, Yun-Chul; Ha, Eun-Hee; Park, Hyesook

    2015-01-01

    Background There are few data on the interaction between temperature and snow and rain precipitation, although they could interact in their effects on road traffic injuries. Methods The integrated database of the Korea Road Traffic Authority was used to calculate the daily frequency of road traffic injuries in Seoul. Weather data included rain and snow precipitation, temperature, pressure, and fog from May 2007 to December 2011. Precipitation of rain and snow were divided into nine and six temperature range categories, respectively. The interactive effects of temperature and rain and snow precipitation on road traffic injuries were analyzed using a generalized additive model with a Poisson distribution. Results The risk of road traffic injuries during snow increased when the temperature was below freezing. Road traffic injuries increased by 6.6% when it was snowing and above 0°C, whereas they increased by 15% when it was snowing and at or below 0°C. In terms of heavy rain precipitation, moderate temperatures were related to an increased prevalence of injuries. When the temperature was 0–20°C, we found a 12% increase in road traffic injuries, whereas it increased by 8.5% and 6.8% when it was <0°C and >20°C, respectively. The interactive effect was consistent across the traffic accident subtypes. Conclusions The effect of adverse weather conditions on road traffic injuries differed depending on the temperature. More road traffic injuries were related to rain precipitation when the temperature was moderate and to snow when it was below freezing. PMID:26073021

  12. Analysis on the Correlation of Traffic Flow in Hainan Province Based on Baidu Search

    NASA Astrophysics Data System (ADS)

    Chen, Caixia; Shi, Chun

    2018-03-01

    Internet search data records user’s search attention and consumer demand, providing necessary database for the Hainan traffic flow model. Based on Baidu Index, with Hainan traffic flow as example, this paper conduct both qualitative and quantitative analysis on the relationship between search keyword from Baidu Index and actual Hainan tourist traffic flow, and build multiple regression model by SPSS.

  13. Geosynchronous platform definition study. Volume 4, Part 1: Traffic analysis and system requirements for the baseline traffic model

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The traffic analyses and system requirements data generated in the study resulted in the development of two traffic models; the baseline traffic model and the new traffic model. The baseline traffic model provides traceability between the numbers and types of geosynchronous missions considered in the study and the entire spectrum of missions foreseen in the total national space program. The information presented pertaining to the baseline traffic model includes: (1) definition of the baseline traffic model, including identification of specific geosynchronous missions and their payload delivery schedules through 1990; (2) Satellite location criteria, including the resulting distribution of the satellite population; (3) Geosynchronous orbit saturation analyses, including the effects of satellite physical proximity and potential electromagnetic interference; and (4) Platform system requirements analyses, including satellite and mission equipment descriptions, the options and limitations in grouping satellites, and on-orbit servicing criteria (both remotely controlled and man-attended).

  14. Traffic placement policies for a multi-band network

    NASA Technical Reports Server (NTRS)

    Maly, Kurt J.; Foudriat, E. C.; Game, David; Mukkamala, R.; Overstreet, C. Michael

    1990-01-01

    Recently protocols were introduced that enable the integration of synchronous traffic (voice or video) and asynchronous traffic (data) and extend the size of local area networks without loss in speed or capacity. One of these is DRAMA, a multiband protocol based on broadband technology. It provides dynamic allocation of bandwidth among clusters of nodes in the total network. A number of traffic placement policies for such networks are proposed and evaluated. Metrics used for performance evaluation include average network access delay, degree of fairness of access among the nodes, and network throughput. The feasibility of the DRAMA protocol is established through simulation studies. DRAMA provides effective integration of synchronous and asychronous traffic due to its ability to separate traffic types. Under the suggested traffic placement policies, the DRAMA protocol is shown to handle diverse loads, mixes of traffic types, and numbers of nodes, as well as modifications to the network structure and momentary traffic overloads.

  15. Application of travel time information for traffic management.

    DOT National Transportation Integrated Search

    2012-03-01

    This report summarizes findings and implementations of probe vehicle data collection based on Bluetooth MAC address matching : technology. Probe vehicle travel time data are studied in the following field deployment case studies: analysis of traffic ...

  16. 2000 West Virginia accident data

    DOT National Transportation Integrated Search

    2000-01-01

    The data contained within this report is extracted, by the : West Virginia Division of Highways, Traffic Engineering Division, from a database of : West Virginia Uniform Traffic Crash Reports submitted to the West Virginia Division of : Motor Vehicle...

  17. 2003 West Virginia crash data

    DOT National Transportation Integrated Search

    2003-01-01

    This report was prepared by Traffic Engineering : personnel, from the West Virginia Division of Highways. The data contained in this : report is collected from Uniform Traffic Crash Reports submitted by state law : enforcement agencies. These law enf...

  18. 2002 West Virginia crash data

    DOT National Transportation Integrated Search

    2003-01-01

    This report was prepared by Traffic Engineering : personnel, from the West Virginia Division of Highways. The data contained in this : report is collected from Uniform Traffic Crash Reports submitted by state law : enforcement agencies. These law enf...

  19. Optimal loop placement and models for length - based vehicle classification and stop - and - go traffic.

    DOT National Transportation Integrated Search

    2011-01-01

    Inductive loops are widely used nationwide for traffic monitoring as a data source for a variety of : needs in generating traffic information for operation and planning analysis, validations of travel : demand models, freight studies, pavement design...

  20. Tire/pavement and environmental traffic noise research study : interim report - 2009 testing.

    DOT National Transportation Integrated Search

    2011-01-01

    This research study is being conducted in response to CDOTs interest in traffic noise in general, and the tire/pavement : interaction in particular. Following a rigid set of testing protocols, data is being collected on highway traffic noise : cha...

  1. Duluth Entertainment Convention Center (DECC) special events traffic flow study : traffic data analysis and signal timing coordination

    DOT National Transportation Integrated Search

    2003-06-01

    Following special events at the Duluth Entertainment Convention Center (DECC) (e.g., conventions, concerts, graduation ceremonies), high volumes of traffic exiting the DECC create substantial congestion at adjacent intersections. The purpose of this ...

  2. A data storage and retrieval model for Louisiana traffic operations data : technical summary.

    DOT National Transportation Integrated Search

    1996-08-01

    The overall goal of this research study was to develop a prototype computer-based indexing model for traffic operation data in DOTD. The methodology included: 1) extraction of state road network, 2) development of geographic reference model, 3) engin...

  3. Data mining tools for the support of traffic signal timing plan development in arterial networks

    DOT National Transportation Integrated Search

    2001-05-01

    Intelligent transportation systems (ITS) include large numbers of traffic sensors that collect enormous quantities of data. The data provided by ITS is necessary for advanced forms of control; however, basic forms of control, primarily time-of-day (T...

  4. Stream traffic data archival, querying, and analysis with TransDec.

    DOT National Transportation Integrated Search

    2011-01-01

    The goal of research was to extend the traffic data analysis of the TransDec (short for : Transportation Decision-Making) system, which was developed under METRANS 09-26 : research grant. The TransDec system is a real-data driven system to support de...

  5. A cost-effective traffic data collection system based on the iDEN mobile telecommunication network.

    DOT National Transportation Integrated Search

    2008-10-01

    This report describes a cost-effective data collection system for Caltrans 170 traffic signal : controller. The data collection system is based on TCP/IP communication over existing : low-cost mobile communication networks and Motorola iDEN1 mobile...

  6. Controller Evaluation of Initial Data Link Air Traffic Control Services, Mini Study 1, Volume 2

    DOT National Transportation Integrated Search

    1988-09-01

    This report details the results of Mini Study 1. This mini study was conducted : at the Federal Aviation Administration (FAA) Technical Center utilizing the Data : Link testbed. Initial Data Link air traffic control services were evaluated : under pa...

  7. Actual situation analyses of rat-run traffic on community streets based on car probe data

    NASA Astrophysics Data System (ADS)

    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.

  8. Application of growing hierarchical SOM for visualisation of network forensics traffic data.

    PubMed

    Palomo, E J; North, J; Elizondo, D; Luque, R M; Watson, T

    2012-08-01

    Digital investigation methods are becoming more and more important due to the proliferation of digital crimes and crimes involving digital evidence. Network forensics is a research area that gathers evidence by collecting and analysing network traffic data logs. This analysis can be a difficult process, especially because of the high variability of these attacks and large amount of data. Therefore, software tools that can help with these digital investigations are in great demand. In this paper, a novel approach to analysing and visualising network traffic data based on growing hierarchical self-organising maps (GHSOM) is presented. The self-organising map (SOM) has been shown to be successful for the analysis of highly-dimensional input data in data mining applications as well as for data visualisation in a more intuitive and understandable manner. However, the SOM has some problems related to its static topology and its inability to represent hierarchical relationships in the input data. The GHSOM tries to overcome these limitations by generating a hierarchical architecture that is automatically determined according to the input data and reflects the inherent hierarchical relationships among them. Moreover, the proposed GHSOM has been modified to correctly treat the qualitative features that are present in the traffic data in addition to the quantitative features. Experimental results show that this approach can be very useful for a better understanding of network traffic data, making it easier to search for evidence of attacks or anomalous behaviour in a network environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. TSAFE Interface Control Document v 2.0

    NASA Technical Reports Server (NTRS)

    Paielli, Russell A.; Bach, Ralph E.

    2013-01-01

    This document specifies the data interface for TSAFE, the Tactical Separation-Assured Flight Environment. TSAFE is a research prototype of a software application program for alerting air traffic controllers to imminent conflicts in enroute airspace. It is intended for Air Route Traffic Control Centers ("Centers") in the U.S. National Airspace System. It predicts trajectories for approximately 3 minutes into the future, searches for conflicts, and sends data about predicted conflicts to the client, which uses the data to alert an air traffic controller of conflicts. TSAFE itself does not provide a graphical user interface.

  10. Intersection Monitor for Traffic-Light-Preemption System

    NASA Technical Reports Server (NTRS)

    Bachelder, Aaron; Foster, Conrad

    2006-01-01

    The figure shows an intersection monitor that is a key subsystem of an emergency traffic-light-preemption system that could be any of the systems described in the three immediately preceding articles and in Systems Would Preempt Traffic Lights for Emergency Vehicles (NPO-30573), NASA Tech Briefs, Vol. 28, No. 10 (October 2004), page 36. This unit is so named because it is installed at an intersection, where it monitors the phases (in the sense of timing) of the traffic lights. The mode of operation of this monitor is independent of the type of traffic-light-controller hardware or software in use at the intersection. Moreover, the design of the monitor is such that (1) the monitor does not, by itself, affect the operation of the traffic- light controller and (2) in the event of a failure of the monitor, the trafficlight controller continues to function normally (albeit without preemption). The monitor is installed in series with the traffic-light controller at an intersection. The control signals of interest are monitored by use of high-impedance taps on affected control lines. These taps are fully isolated and further protected by high-voltage diodes that prevent any voltages or short circuits that arise within the monitor from affecting the controller. The signals from the taps are processed digitally and cleaned up by use of high-speed logic gates, and the resulting data are passed on to other parts of the traffic-light-preemption intersection subsystem. The data are compared continuously with data from vehicles and used to calculate timing for reliable preemption of the traffic lights. The pedestrian crossing at the intersection is also monitored, and pedestrians are warned not to cross during preemption.

  11. Forecasting mortality of road traffic injuries in China using seasonal autoregressive integrated moving average model.

    PubMed

    Zhang, Xujun; Pang, Yuanyuan; Cui, Mengjing; Stallones, Lorann; Xiang, Huiyun

    2015-02-01

    Road traffic injuries have become a major public health problem in China. This study aimed to develop statistical models for predicting road traffic deaths and to analyze seasonality of deaths in China. A seasonal autoregressive integrated moving average (SARIMA) model was used to fit the data from 2000 to 2011. Akaike Information Criterion, Bayesian Information Criterion, and mean absolute percentage error were used to evaluate the constructed models. Autocorrelation function and partial autocorrelation function of residuals and Ljung-Box test were used to compare the goodness-of-fit between the different models. The SARIMA model was used to forecast monthly road traffic deaths in 2012. The seasonal pattern of road traffic mortality data was statistically significant in China. SARIMA (1, 1, 1) (0, 1, 1)12 model was the best fitting model among various candidate models; the Akaike Information Criterion, Bayesian Information Criterion, and mean absolute percentage error were -483.679, -475.053, and 4.937, respectively. Goodness-of-fit testing showed nonautocorrelations in the residuals of the model (Ljung-Box test, Q = 4.86, P = .993). The fitted deaths using the SARIMA (1, 1, 1) (0, 1, 1)12 model for years 2000 to 2011 closely followed the observed number of road traffic deaths for the same years. The predicted and observed deaths were also very close for 2012. This study suggests that accurate forecasting of road traffic death incidence is possible using SARIMA model. The SARIMA model applied to historical road traffic deaths data could provide important evidence of burden of road traffic injuries in China. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Initial Design and Experimental Implementation of the Traffic Advisory Service of ATARS

    DTIC Science & Technology

    1980-11-03

    Traffic 6. Performing Organization Code Advisory Service of ATARS 7. Author(s) 8. Performing Organization Report No Jeffrey L. Gertz ATC-101 9...and Resolution Service ( ATARS ) is a ground-based collision avoidance system which utilizes surveillance data from the Discrete Address Beacon System...to aircraft via the DABS data link. ATARS provides both a traffic advisory and a resolution (collision avoidance) service to aircraft equipped with a

  13. Web application and database modeling of traffic impact analysis using Google Maps

    NASA Astrophysics Data System (ADS)

    Yulianto, Budi; Setiono

    2017-06-01

    Traffic impact analysis (TIA) is a traffic study that aims at identifying the impact of traffic generated by development or change in land use. In addition to identifying the traffic impact, TIA is also equipped with mitigation measurement to minimize the arising traffic impact. TIA has been increasingly important since it was defined in the act as one of the requirements in the proposal of Building Permit. The act encourages a number of TIA studies in various cities in Indonesia, including Surakarta. For that reason, it is necessary to study the development of TIA by adopting the concept Transportation Impact Control (TIC) in the implementation of the TIA standard document and multimodal modeling. It includes TIA's standardization for technical guidelines, database and inspection by providing TIA checklists, monitoring and evaluation. The research was undertaken by collecting the historical data of junctions, modeling of the data in the form of relational database, building a user interface for CRUD (Create, Read, Update and Delete) the TIA data in the form of web programming with Google Maps libraries. The result research is a system that provides information that helps the improvement and repairment of TIA documents that exist today which is more transparent, reliable and credible.

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

    PubMed

    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 of road traffic crashes resulting in injuries (fatal and non fatal). The pooled rate ratio was 0.89 (0.80, 1.00 95% CI). Nine studies reported the total number of road traffic crashes. The pooled rate ratio was 0.95 (0.81, 1.11 95% CI). Thirteen trials reported the number of pedestrian-motor vehicle collisions. The pooled rate ratio was 1.00 (0.84, 1.18). There was significant heterogeneity for the total number of crashes and deaths and injuries. The results from this review suggest that area-wide traffic calming in towns and cities may be a promising intervention for reducing the number of road traffic injuries, and deaths. However, further rigorous evaluations of this intervention are needed.

  15. Geographic Information System (GIS) capabilities in traffic accident information management: a qualitative approach

    PubMed Central

    Ahmadi, Maryam; Valinejadi, Ali; Goodarzi, Afshin; Safari, Ameneh; Hemmat, Morteza; Majdabadi, Hesamedin Askari; Mohammadi, Ali

    2017-01-01

    Background Traffic accidents are one of the more important national and international issues, and their consequences are important for the political, economical, and social level in a country. Management of traffic accident information requires information systems with analytical and accessibility capabilities to spatial and descriptive data. Objective The aim of this study was to determine the capabilities of a Geographic Information System (GIS) in management of traffic accident information. Methods This qualitative cross-sectional study was performed in 2016. In the first step, GIS capabilities were identified via literature retrieved from the Internet and based on the included criteria. Review of the literature was performed until data saturation was reached; a form was used to extract the capabilities. In the second step, study population were hospital managers, police, emergency, statisticians, and IT experts in trauma, emergency and police centers. Sampling was purposive. Data was collected using a questionnaire based on the first step data; validity and reliability were determined by content validity and Cronbach’s alpha of 75%. Data was analyzed using the decision Delphi technique. Results GIS capabilities were identified in ten categories and 64 sub-categories. Import and process of spatial and descriptive data and so, analysis of this data were the most important capabilities of GIS in traffic accident information management. Conclusion Storing and retrieving of descriptive and spatial data, providing statistical analysis in table, chart and zoning format, management of bad structure issues, determining the cost effectiveness of the decisions and prioritizing their implementation were the most important capabilities of GIS which can be efficient in the management of traffic accident information. PMID:28848627

  16. [Traffic accidents: a qualitative approach from Campinas, São Paulo, Brazil].

    PubMed

    Queiroz, Marcos S; Oliveira, Patrícia C P

    2002-01-01

    This article takes an interdisciplinary qualitative approach to the problem of traffic accidents in Campinas, São Paulo, Brazil. The authors begin by analyzing the "municipalization" (i.e., decentralization to the municipal level) of transport and traffic management in Campinas based on social representations by members of the local government's technical staff. Data demonstrate a significant drop in traffic accident mortality in Campinas in the last ten years. The findings illustrate how new transport and traffic policies had several positive effects. Special attention is given to the objectives, strategies, and obstacles dealt with by local government in the "municipalization" of traffic. The paper concludes by emphasizing the need for specific public policies to revitalize urban mass transportation, including special traffic safety educational programs.

  17. Traffic accidents in Iran, a decade of progress but still challenges ahead.

    PubMed

    Lankarani, Kamran B; Sarikhani, Yaser; Heydari, Seyed Taghi; Joulaie, Hasan; Maharlouei, Najmeh; Peimani, Payam; Ahmadi, Seyed Mehdi; Khorasani-Zavareh, Davoud; Soori, Hamid; Davoudi-Kiakalayeh, Ali; Masoumi, Gholamreza

    2014-01-01

    Iran has had incremental incidence of traffic accident mortality since introduction of mechanization about a century ago. But the newest data from Iran show decrease in the absolute number of deaths, death per 10,000 vehicles and death per 100, 000 populations. Despite its huge impact on health and economy, research in the field of traffic crashes is still scant and there are still deficiencies in problem oriented research on traffic accidents. Actual cooperation of policy makers, executive bodies and academician could build platform for intersectoral discussion of different aspects of traffic accidents and could reduce burden of traffic accidents.

  18. Spatial distribution of traffic in a cellular mobile data network

    NASA Astrophysics Data System (ADS)

    Linnartz, J. P. M. G.

    1987-02-01

    The use of integral transforms of the probability density function for the received power to analyze the relation between the spatial distributions of offered and throughout packet traffic in a mobile radio network with Rayleigh fading channels and ALOHA multiple access was assessed. A method to obtain the spatial distribution of throughput traffic from a prescribed spatial distribution of offered traffic is presented. Incoherent and coherent addition of interference signals is considered. The channel behavior for heavy traffic loads is studied. In both the incoherent and coherent case, the spatial distribution of offered traffic required to ensure a prescribed spatially uniform throughput is synthesized numerically.

  19. Oceanic Situational Awareness Over the Western Atlantic Track Routing System

    NASA Technical Reports Server (NTRS)

    Welch, Bryan; Greenfeld, Israel

    2005-01-01

    Air traffic control (ATC) mandated, aircraft separations over the oceans impose a limitation on traffic capacity for a given corridor, given the projected traffic growth over the Western Atlantic Track Routing System (WATRS). The separations result from a lack of acceptable situational awareness over oceans where radar position updates are not available. This study considers the use of Automatic Dependent Surveillance (ADS) data transmitted over a commercial satellite communications system as an approach to provide ATC with the needed situational awareness and thusly allow for reduced aircraft separations. This study uses Federal Aviation Administration data from a single day for the WATRS corridor to analyze traffic loading to be used as a benchmark against which to compare several approaches for coordinating data transmissions from the aircraft to the satellites.

  20. Development of a mobile probe-based traffic data fusion and flow management platform for innovative public-private information-based partnerships.

    DOT National Transportation Integrated Search

    2011-10-17

    "Under the aegis of Intelligent Transportation Systems (ITS), real-time traffic information provision strategies are being proposed to manage traffic congestion, alleviate the effects of incidents, enhance response efficiency after disasters, and imp...

  1. Probabilistic Predictions of Traffic Demand for En Route Sectors Based on Individual Flight Data

    DOT National Transportation Integrated Search

    2010-01-01

    The Traffic Flow Management System (TFMS) predicts the demand for each sector, and traffic managers use these predictions to spot possible congestion and to take measures to prevent it. These predictions of sector demand, however, are currently made ...

  2. State of the art evaluation of traffic detection and monitoring systems. Volume 1, phases A & B : design [Summary

    DOT National Transportation Integrated Search

    2007-10-01

    Accurate, complete, and timely traffic data is critical to the effective management of Arizonas highway system. Limitations in current traffic monitoring abilities are an ongoing challenge for the Arizona Department of Transportation (ADOT) and fo...

  3. Operational improvements at traffic circles : safety analysis, final report, December 2008.

    DOT National Transportation Integrated Search

    2008-12-01

    The purpose of this study was to improve the safety and operation at three traffic circles in New : Jersey. To do this, data were collected at the traffic circles to allow researchers to model the : circles using the PARAMICS software simulation pack...

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

    DOT National Transportation Integrated Search

    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...

  5. Seasonal characterisation of maritime traffic and the relationship with cetacean presence in the Western Mediterranean Sea.

    PubMed

    Campana, I; Angeletti, D; Crosti, R; Luperini, C; Ruvolo, A; Alessandrini, A; Arcangeli, A

    2017-02-15

    Seasonal maritime traffic was investigated in relation to cetaceans, through direct observations (July 2013-June 2015) along three fixed transects in Western Mediterranean. Visually obtained vessel abundance was compared with Automatic Identification System data to explore if the two methods provided different results. Traffic intensity and composition were characterised by seasons and vessel categories. Finally, cetacean presence was investigated in relation to traffic by measuring the difference of vessel abundance in the presence and absence of animal sightings. Results showed that visual sampling was consistent with AIS data, providing more information on small-medium vessels. Traffic was more intense and diverse in Spring/Summer, and the highest vessel abundance and seasonal variations in composition emerged for inshore subareas. The difference of traffic in the presence and absence of cetaceans was higher in most offshore subareas in Spring/Summer, verified for B. physalus and S. coeruleoalba; in inshore waters, mostly occupied by T. truncatus, no significant differences emerged. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Controller Evaluation of Initial Data Link Air Traffic Control Services: Mini Study 2 Volume II

    DOT National Transportation Integrated Search

    1989-03-01

    This report details the results of Mini Study 2. This Mini Study was conducted at the Federal Aviation Administration (FAA) Technical Center utilizing the Data Link test bed. Initial Data Link air traffic control services were evaluated under part ta...

  7. Controller Evaluation of Initial Data Link Air Traffic Control Services: Mini Study 2 Volume I

    DOT National Transportation Integrated Search

    1989-03-01

    This report details the results of Mini Study 2. This Mini Study was conducted at the Federal Aviation Administration (FAA) Technical Center utilizing the Data Link test bed. Initial Data Link air traffic control services were evaluated under part ta...

  8. Controller Evaluation of Initial Data Link Air Traffic Control Services, Mini Study 1, Volume 1

    DOT National Transportation Integrated Search

    1988-09-01

    This report details the results of Mini Study 1. This mini study was conducted : at the Federal Aviation (FAA) Technical Center utilizing the Data Link testbed. : Initial Data Link air traffic control services were under part task simulation : condit...

  9. Integrating Emerging Data Sources into Operational Practice : Opportunities for Integration of Emerging Data for Traffic Management and TMCs.

    DOT National Transportation Integrated Search

    2017-11-01

    With the emergence of data generated from connected vehicles, connected travelers, and connected infrastructure, the capabilities of traffic management systems or centers (TMCs) will need to be improved to allow agencies to compile and benefit from u...

  10. An algorithm for generating data accessibility recommendations for flight deck Automatic Dependent Surveillance-Broadcast (ADS-B) applications

    DOT National Transportation Integrated Search

    2014-09-09

    Automatic Dependent Surveillance-Broadcast (ADS-B) In technology supports the display of traffic data on Cockpit Displays of Traffic Information (CDTIs). The data are used by flightcrews to perform defined self-separation procedures, such as the in-t...

  11. 2003 New Mexico traffic crash information

    DOT National Transportation Integrated Search

    2005-02-01

    reviews traffic crash data in New Mexico from January : through December, 2003. It presents crash data in the : form of graphs for those who prefer an impressionistic : view and tables for those who require reference : information. Maps are provided ...

  12. 2001 West Virginia crash data

    DOT National Transportation Integrated Search

    2001-01-01

    This report was prepared by Traffic Engineering : personnel, from the West Virginia Division of Highways. The data contained in this : report is collected from Uniform Traffic Crash Reports submitted to the Division of : Motor Vehicles by state law e...

  13. Roadway Traffic Data Collection from Mobile Platforms, Technical Summary

    DOT National Transportation Integrated Search

    2017-07-28

    This project empirically investigates the traffic flow estimations from different types of data collected from two types of mobile platforms transit buses in service operations and a van driven to emulate bus coverage that repeatedly traverse...

  14. Computerized traffic data analysis system.

    DOT National Transportation Integrated Search

    1975-01-01

    The techniques of collecting detailed traffic data for a given site are well known. A popular method uses chart recorders in combination with various vehicle sensing devices, such as tape switches, to provide an accurate pictoral display of the traff...

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Visual traffic jam analysis based on trajectory data.

    PubMed

    Wang, Zuchao; Lu, Min; Yuan, Xiaoru; Zhang, Junping; van de Wetering, Huub

    2013-12-01

    In this work, we present an interactive system for visual analysis of urban traffic congestion based on GPS trajectories. For these trajectories we develop strategies to extract and derive traffic jam information. After cleaning the trajectories, they are matched to a road network. Subsequently, traffic speed on each road segment is computed and traffic jam events are automatically detected. Spatially and temporally related events are concatenated in, so-called, traffic jam propagation graphs. These graphs form a high-level description of a traffic jam and its propagation in time and space. Our system provides multiple views for visually exploring and analyzing the traffic condition of a large city as a whole, on the level of propagation graphs, and on road segment level. Case studies with 24 days of taxi GPS trajectories collected in Beijing demonstrate the effectiveness of our system.

  17. Nonlinear stability of traffic models and the use of Lyapunov vectors for estimating the traffic state

    NASA Astrophysics Data System (ADS)

    Palatella, Luigi; Trevisan, Anna; Rambaldi, Sandro

    2013-08-01

    Valuable information for estimating the traffic flow is obtained with current GPS technology by monitoring position and velocity of vehicles. In this paper, we present a proof of concept study that shows how the traffic state can be estimated using only partial and noisy data by assimilating them in a dynamical model. Our approach is based on a data assimilation algorithm, developed by the authors for chaotic geophysical models, designed to be equivalent but computationally much less demanding than the traditional extended Kalman filter. Here we show that the algorithm is even more efficient if the system is not chaotic and demonstrate by numerical experiments that an accurate reconstruction of the complete traffic state can be obtained at a very low computational cost by monitoring only a small percentage of vehicles.

  18. Surface Map Traffic Intent Displays and Net-Centric Data-link Communications for NextGen

    NASA Technical Reports Server (NTRS)

    Shelton, Kevin J.; Prinzel, Lawrence J., III; Jones, Denise R.; Allamandola, Angela S.; Arthur, Jarvis J., III; Bailey, Randall E.

    2009-01-01

    By 2025, U.S. air traffic is predicted to increase three fold and may strain the current air traffic management system, which may not be able to accommodate this growth. In response to this challenge, a revolutionary new concept has been proposed for U.S. aviation operations, termed the Next Generation Air Transportation System or "NextGen". Many key capabilities are being identified to enable NextGen, including the use of data-link communications. Because NextGen represents a radically different approach to air traffic management and requires a dramatic shift in the tasks, roles, and responsibilities for the flight deck, there are numerous research issues and challenges that must be overcome to ensure a safe, sustainable air transportation system. Flight deck display and crew-vehicle interaction concepts are being developed that proactively investigate and overcome potential technology and safety barriers that might otherwise constrain the full realization of NextGen. The paper describes simulation research, conducted at National Aeronautics and Space Administration (NASA) Langley Research Center, examining data-link communications and traffic intent data during envisioned four-dimensional trajectory (4DT)-based and equivalent visual (EV) surface operations. Overall, the results suggest that controller pilot data-link communications (CPDLC) with the use of mandatory pilot read-back of all clearances significantly enhanced situation awareness for 4DT and EV surface operations. The depiction of graphical traffic state and intent information on the surface map display further enhanced off-nominal detection and pilot qualitative reports of safety and awareness.

  19. Semantic Representation and Scale-Up of Integrated Air Traffic Management Data

    NASA Technical Reports Server (NTRS)

    Keller, Richard M.; Ranjan, Shubha; Wei, Mei Y.; Eshow, Michelle M.

    2016-01-01

    Each day, the global air transportation industry generates a vast amount of heterogeneous data from air carriers, air traffic control providers, and secondary aviation entities handling baggage, ticketing, catering, fuel delivery, and other services. Generally, these data are stored in isolated data systems, separated from each other by significant political, regulatory, economic, and technological divides. These realities aside, integrating aviation data into a single, queryable, big data store could enable insights leading to major efficiency, safety, and cost advantages. In this paper, we describe an implemented system for combining heterogeneous air traffic management data using semantic integration techniques. The system transforms data from its original disparate source formats into a unified semantic representation within an ontology-based triple store. Our initial prototype stores only a small sliver of air traffic data covering one day of operations at a major airport. The paper also describes our analysis of difficulties ahead as we prepare to scale up data storage to accommodate successively larger quantities of data -- eventually covering all US commercial domestic flights over an extended multi-year timeframe. We review several approaches to mitigating scale-up related query performance concerns.

  20. Problems in air traffic management. III., Implications of age for training and job performance of air traffic controllers.

    DOT National Transportation Integrated Search

    1962-02-01

    The relationships between chronological age upon entry into ATC training and school and job performance were examined in five samples of air traffic controller trainees. The data confirm conclusively the existence of an inverse relationship such that...

  1. 14 CFR Sec. 19-2 - Maintenance of data.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... operations are reported by the air carrier in operational control of the aircraft. The traffic moving under... shall maintain its operating statistics, covering the movement of traffic in accordance with the uniform classifications prescribed. Codes are prescribed for each operating element and service class. All traffic...

  2. Development of prototype decision support systems for real-time freeway traffic routing. Volume I.

    DOT National Transportation Integrated Search

    1998-01-01

    For a traffic management system (TMS) to improve traffic flow, TMS operators must develop effective routing strategies based on the data collected by the system. The purpose of this research was to build prototype decision support systems (DSS) for t...

  3. Multi-level Bayesian safety analysis with unprocessed Automatic Vehicle Identification data for an urban expressway.

    PubMed

    Shi, Qi; Abdel-Aty, Mohamed; Yu, Rongjie

    2016-03-01

    In traffic safety studies, crash frequency modeling of total crashes is the cornerstone before proceeding to more detailed safety evaluation. The relationship between crash occurrence and factors such as traffic flow and roadway geometric characteristics has been extensively explored for a better understanding of crash mechanisms. In this study, a multi-level Bayesian framework has been developed in an effort to identify the crash contributing factors on an urban expressway in the Central Florida area. Two types of traffic data from the Automatic Vehicle Identification system, which are the processed data capped at speed limit and the unprocessed data retaining the original speed were incorporated in the analysis along with road geometric information. The model framework was proposed to account for the hierarchical data structure and the heterogeneity among the traffic and roadway geometric data. Multi-level and random parameters models were constructed and compared with the Negative Binomial model under the Bayesian inference framework. Results showed that the unprocessed traffic data was superior. Both multi-level models and random parameters models outperformed the Negative Binomial model and the models with random parameters achieved the best model fitting. The contributing factors identified imply that on the urban expressway lower speed and higher speed variation could significantly increase the crash likelihood. Other geometric factors were significant including auxiliary lanes and horizontal curvature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A comparative study of outlier detection for large-scale traffic data by one-class SVM and kernel density estimation

    NASA Astrophysics Data System (ADS)

    Ngan, Henry Y. T.; Yung, Nelson H. C.; Yeh, Anthony G. O.

    2015-02-01

    This paper aims at presenting a comparative study of outlier detection (OD) for large-scale traffic data. The traffic data nowadays are massive in scale and collected in every second throughout any modern city. In this research, the traffic flow dynamic is collected from one of the busiest 4-armed junction in Hong Kong in a 31-day sampling period (with 764,027 vehicles in total). The traffic flow dynamic is expressed in a high dimension spatial-temporal (ST) signal format (i.e. 80 cycles) which has a high degree of similarities among the same signal and across different signals in one direction. A total of 19 traffic directions are identified in this junction and lots of ST signals are collected in the 31-day period (i.e. 874 signals). In order to reduce its dimension, the ST signals are firstly undergone a principal component analysis (PCA) to represent as (x,y)-coordinates. Then, these PCA (x,y)-coordinates are assumed to be conformed as Gaussian distributed. With this assumption, the data points are further to be evaluated by (a) a correlation study with three variant coefficients, (b) one-class support vector machine (SVM) and (c) kernel density estimation (KDE). The correlation study could not give any explicit OD result while the one-class SVM and KDE provide average 59.61% and 95.20% DSRs, respectively.

  5. Optimization of traffic data collection for specific pavement design applications.

    DOT National Transportation Integrated Search

    2006-05-01

    The objective of this study is to establish the minimum traffic data collection effort required for pavement design applications satisfying a maximum acceptable error under a prescribed confidence level. The approach consists of simulating the traffi...

  6. Summary of key benefits 1989-2015

    DOT National Transportation Integrated Search

    2017-01-01

    The LTPP program relies on data collected by weigh-in-motion systems that measure the traffic stream The LTPP program receives and analyzes data from weigh-in-motion systems that measure traffic streams. For example, weigh-in-motion measurements coll...

  7. Estimate benefits of crowdsourced data from social media.

    DOT National Transportation Integrated Search

    2014-12-01

    Traffic Management Centers (TMCs) acquire, process, and integrate data in a variety of ways to support real-time operations. Crowdsourcing has been identified as one of the top trends and technologies that traffic management agencies can adapt and ta...

  8. Development of a traffic noise prediction model for an urban environment.

    PubMed

    Sharma, Asheesh; Bodhe, G L; Schimak, G

    2014-01-01

    The objective of this study is to develop a traffic noise model under diverse traffic conditions in metropolitan cities. The model has been developed to calculate equivalent traffic noise based on four input variables i.e. equivalent traffic flow (Q e ), equivalent vehicle speed (S e ) and distance (d) and honking (h). The traffic data is collected and statistically analyzed in three different cases for 15-min during morning and evening rush hours. Case I represents congested traffic where equivalent vehicle speed is <30 km/h while case II represents free-flowing traffic where equivalent vehicle speed is >30 km/h and case III represents calm traffic where no honking is recorded. The noise model showed better results than earlier developed noise model for Indian traffic conditions. A comparative assessment between present and earlier developed noise model has also been presented in the study. The model is validated with measured noise levels and the correlation coefficients between measured and predicted noise levels were found to be 0.75, 0.83 and 0.86 for case I, II and III respectively. The noise model performs reasonably well under different traffic conditions and could be implemented for traffic noise prediction at other region as well.

  9. Analysis of Air Traffic Track Data with the AutoBayes Synthesis System

    NASA Technical Reports Server (NTRS)

    Schumann, Johann Martin Philip; Cate, Karen; Lee, Alan G.

    2010-01-01

    The Next Generation Air Traffic System (NGATS) is aiming to provide substantial computer support for the air traffic controllers. Algorithms for the accurate prediction of aircraft movements are of central importance for such software systems but trajectory prediction has to work reliably in the presence of unknown parameters and uncertainties. We are using the AutoBayes program synthesis system to generate customized data analysis algorithms that process large sets of aircraft radar track data in order to estimate parameters and uncertainties. In this paper, we present, how the tasks of finding structure in track data, estimation of important parameters in climb trajectories, and the detection of continuous descent approaches can be accomplished with compact task-specific AutoBayes specifications. We present an overview of the AutoBayes architecture and describe, how its schema-based approach generates customized analysis algorithms, documented C/C++ code, and detailed mathematical derivations. Results of experiments with actual air traffic control data are discussed.

  10. Data Mining for Understanding and Improving Decision-making Affecting Ground Delay Programs

    NASA Technical Reports Server (NTRS)

    Kulkarni, Deepak; Wang, Yao; Sridhar, Banavar

    2013-01-01

    The continuous growth in the demand for air transportation results in an imbalance between airspace capacity and traffic demand. The airspace capacity of a region depends on the ability of the system to maintain safe separation between aircraft in the region. In addition to growing demand, the airspace capacity is severely limited by convective weather. During such conditions, traffic managers at the FAA's Air Traffic Control System Command Center (ATCSCC) and dispatchers at various Airlines' Operations Center (AOC) collaborate to mitigate the demand-capacity imbalance caused by weather. The end result is the implementation of a set of Traffic Flow Management (TFM) initiatives such as ground delay programs, reroute advisories, flow metering, and ground stops. Data Mining is the automated process of analyzing large sets of data and then extracting patterns in the data. Data mining tools are capable of predicting behaviors and future trends, allowing an organization to benefit from past experience in making knowledge-driven decisions.

  11. Data traffic reduction schemes for sparse Cholesky factorizations

    NASA Technical Reports Server (NTRS)

    Naik, Vijay K.; Patrick, Merrell L.

    1988-01-01

    Load distribution schemes are presented which minimize the total data traffic in the Cholesky factorization of dense and sparse, symmetric, positive definite matrices on multiprocessor systems with local and shared memory. The total data traffic in factoring an n x n sparse, symmetric, positive definite matrix representing an n-vertex regular 2-D grid graph using n (sup alpha), alpha is equal to or less than 1, processors are shown to be O(n(sup 1 + alpha/2)). It is O(n(sup 3/2)), when n (sup alpha), alpha is equal to or greater than 1, processors are used. Under the conditions of uniform load distribution, these results are shown to be asymptotically optimal. The schemes allow efficient use of up to O(n) processors before the total data traffic reaches the maximum value of O(n(sup 3/2)). The partitioning employed within the scheme, allows a better utilization of the data accessed from shared memory than those of previously published methods.

  12. An association between dietary habits and traffic accidents in patients with chronic liver disease: A data-mining analysis

    PubMed Central

    KAWAGUCHI, TAKUMI; SUETSUGU, TAKURO; OGATA, SHYOU; IMANAGA, MINAMI; ISHII, KUMIKO; ESAKI, NAO; SUGIMOTO, MASAKO; OTSUYAMA, JYURI; NAGAMATSU, AYU; TANIGUCHI, EITARO; ITOU, MINORU; ORIISHI, TETSUHARU; IWASAKI, SHOKO; MIURA, HIROKO; TORIMURA, TAKUJI

    2016-01-01

    The incidence of traffic accidents in patients with chronic liver disease (CLD) is high in the USA. However, the characteristics of patients, including dietary habits, differ between Japan and the USA. The present study investigated the incidence of traffic accidents in CLD patients and the clinical profiles associated with traffic accidents in Japan using a data-mining analysis. A cross-sectional study was performed and 256 subjects [148 CLD patients (CLD group) and 106 patients with other digestive diseases (disease control group)] were enrolled; 2 patients were excluded. The incidence of traffic accidents was compared between the two groups. Independent factors for traffic accidents were analyzed using logistic regression and decision-tree analyses. The incidence of traffic accidents did not differ between the CLD and disease control groups (8.8 vs. 11.3%). The results of the logistic regression analysis showed that yoghurt consumption was the only independent risk factor for traffic accidents (odds ratio, 0.37; 95% confidence interval, 0.16–0.85; P=0.0197). Similarly, the results of the decision-tree analysis showed that yoghurt consumption was the initial divergence variable. In patients who consumed yoghurt habitually, the incidence of traffic accidents was 6.6%, while that in patients who did not consume yoghurt was 16.0%. CLD was not identified as an independent factor in the logistic regression and decision-tree analyses. In conclusion, the difference in the incidence of traffic accidents in Japan between the CLD and disease control groups was insignificant. Furthermore, yoghurt consumption was an independent negative risk factor for traffic accidents in patients with digestive diseases, including CLD. PMID:27123257

  13. An association between dietary habits and traffic accidents in patients with chronic liver disease: A data-mining analysis.

    PubMed

    Kawaguchi, Takumi; Suetsugu, Takuro; Ogata, Shyou; Imanaga, Minami; Ishii, Kumiko; Esaki, Nao; Sugimoto, Masako; Otsuyama, Jyuri; Nagamatsu, Ayu; Taniguchi, Eitaro; Itou, Minoru; Oriishi, Tetsuharu; Iwasaki, Shoko; Miura, Hiroko; Torimura, Takuji

    2016-05-01

    The incidence of traffic accidents in patients with chronic liver disease (CLD) is high in the USA. However, the characteristics of patients, including dietary habits, differ between Japan and the USA. The present study investigated the incidence of traffic accidents in CLD patients and the clinical profiles associated with traffic accidents in Japan using a data-mining analysis. A cross-sectional study was performed and 256 subjects [148 CLD patients (CLD group) and 106 patients with other digestive diseases (disease control group)] were enrolled; 2 patients were excluded. The incidence of traffic accidents was compared between the two groups. Independent factors for traffic accidents were analyzed using logistic regression and decision-tree analyses. The incidence of traffic accidents did not differ between the CLD and disease control groups (8.8 vs. 11.3%). The results of the logistic regression analysis showed that yoghurt consumption was the only independent risk factor for traffic accidents (odds ratio, 0.37; 95% confidence interval, 0.16-0.85; P=0.0197). Similarly, the results of the decision-tree analysis showed that yoghurt consumption was the initial divergence variable. In patients who consumed yoghurt habitually, the incidence of traffic accidents was 6.6%, while that in patients who did not consume yoghurt was 16.0%. CLD was not identified as an independent factor in the logistic regression and decision-tree analyses. In conclusion, the difference in the incidence of traffic accidents in Japan between the CLD and disease control groups was insignificant. Furthermore, yoghurt consumption was an independent negative risk factor for traffic accidents in patients with digestive diseases, including CLD.

  14. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2009

    DOT National Transportation Integrated Search

    2009-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  15. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2008

    DOT National Transportation Integrated Search

    2008-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  16. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2007

    DOT National Transportation Integrated Search

    2007-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  17. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2006

    DOT National Transportation Integrated Search

    2006-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  18. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2005

    DOT National Transportation Integrated Search

    2005-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  19. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2003

    DOT National Transportation Integrated Search

    2003-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  20. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2004

    DOT National Transportation Integrated Search

    2004-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  1. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2008

    DOT National Transportation Integrated Search

    2008-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  2. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2009

    DOT National Transportation Integrated Search

    2009-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  3. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2007

    DOT National Transportation Integrated Search

    2007-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  4. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2003

    DOT National Transportation Integrated Search

    2003-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  5. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2006

    DOT National Transportation Integrated Search

    2006-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  6. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2005

    DOT National Transportation Integrated Search

    2005-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  7. Data Bank 28IM(FF) - T-100 International Market Data, US Air Carriers Traffic and Capacity Data - 3 Year Restricted (includes foreign point and foreign point by US Carrier) : [2004

    DOT National Transportation Integrated Search

    2004-01-01

    This CD presents data reported by U.S. carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data are often referred to as either "market" or on-flight ori...

  8. The Impact of the Thai Motorcycle Transition on Road Traffic Injury: Thai Cohort Study Results

    PubMed Central

    Berecki-Gisolf, Janneke; Yiengprugsawan, Vasoontara; Kelly, Matthew; McClure, Roderick; Seubsman, Sam-ang; Sleigh, Adrian

    2015-01-01

    Objectives The aim of this study was to investigate the impact of motorcycle to car transitioning and urbanisation on traffic injury rates in Thailand. Design Analysis of two consecutive surveys of a large national cohort study. Setting Thailand. Participants The data derived from 57,154 Thai Cohort Study (TCS) participants who provided relevant data on both the 2005 and 2009 surveys. Primary and secondary outcome measures Motorcycle and car traffic crash injury self-reported in 2009, with twelve months’ recall. Results In 2009, 5608(10%) participants reported a traffic crash injury. Most crashes involved a motorcycle (74%). Car access increased and motorcycle use decreased between 2005 and 2009. Among those who used a motorcycle at both time points, traffic injury incidence was 2.8 times greater compared to those who did not use a motorcycle at either time point. Multivariable logistic regression models were used to test longitudinal and cross sectional factors associated with traffic crash injury: in the adjusted model, cars were negatively and motorcycles positively associated with injury. Living in an urban area was not injury protective in the adjusted model of traffic crash injury. Conclusions Ongoing urbanisation in Thailand can be expected to lead to further reductions in road traffic injuries based on transition from motorcycles to cars in urban areas. Cities, however, do not provide an intrinsically safer traffic environment. To accommodate a safe transition to car use in Thailand, traffic infrastructural changes anticipating the growing car density in urban areas is warranted. PMID:25826214

  9. Epidemiologic Pattern of Fatal Traffic Injuries among Iranian Drivers; 2004–2010

    PubMed Central

    BAKHTIYARI, Mahmood; MEHMANDAR, Mohammad Reza; RIAHI, Seyed Mohammad; MANSOURNIA, Mohammad Ali; SARTIPI, Majid; BAHADORIMONFARED, Ayad

    2016-01-01

    Background: Due to their specific nature, such as high incidence, high intensity and direct involvement of all members of society, traffic injuries are of particular importance. Through a mega data, this study investigated the epidemiological aspects and depict current situation of road traffic injuries in Iran. Methods: Using legal medicine and traffic police data, deaths from road traffic injuries in men were predicted through determining the most appropriate model for death using time series statistical models; and then most important human factors associated with it in a period of 6 yr in Iran was analyzed using multi-nominal regression model. Results: The frequency of deaths from traffic injuries in the last seven years was 172,834 cases and the number of deaths at the accident scene was 42798 cases, of which 24.24% (41,971 cases) were recorded by the Traffic Police experts. Death rate from traffic injuries has been declined from 38 cases per 100,000 people in 2004 to 31 cases per 100,000 people between 2009 and 2010. Fatigue and sleepiness (AOR=10.36, 95% CI: 8.41–13.3) was the most significant human risk factors for death outcome in the urban and suburban traffic injuries. According to the predictions, the death rate is about 16488 (CI 95%, 8531–24364) for the year 2012. Conclusion: Despite all measures to prevent such injuries, even fatal injuries have still a high incidence. Intervention in the human risk factors field would be more effective due to their important roles in traffic injuries in Iran. PMID:27252920

  10. Evaluation of Anomaly Detection Method Based on Pattern Recognition

    NASA Astrophysics Data System (ADS)

    Fontugne, Romain; Himura, Yosuke; Fukuda, Kensuke

    The number of threats on the Internet is rapidly increasing, and anomaly detection has become of increasing importance. High-speed backbone traffic is particularly degraded, but their analysis is a complicated task due to the amount of data, the lack of payload data, the asymmetric routing and the use of sampling techniques. Most anomaly detection schemes focus on the statistical properties of network traffic and highlight anomalous traffic through their singularities. In this paper, we concentrate on unusual traffic distributions, which are easily identifiable in temporal-spatial space (e.g., time/address or port). We present an anomaly detection method that uses a pattern recognition technique to identify anomalies in pictures representing traffic. The main advantage of this method is its ability to detect attacks involving mice flows. We evaluate the parameter set and the effectiveness of this approach by analyzing six years of Internet traffic collected from a trans-Pacific link. We show several examples of detected anomalies and compare our results with those of two other methods. The comparison indicates that the only anomalies detected by the pattern-recognition-based method are mainly malicious traffic with a few packets.

  11. On sequential data assimilation for scalar macroscopic traffic flow models

    NASA Astrophysics Data System (ADS)

    Blandin, Sébastien; Couque, Adrien; Bayen, Alexandre; Work, Daniel

    2012-09-01

    We consider the problem of sequential data assimilation for transportation networks using optimal filtering with a scalar macroscopic traffic flow model. Properties of the distribution of the uncertainty on the true state related to the specific nonlinearity and non-differentiability inherent to macroscopic traffic flow models are investigated, derived analytically and analyzed. We show that nonlinear dynamics, by creating discontinuities in the traffic state, affect the performances of classical filters and in particular that the distribution of the uncertainty on the traffic state at shock waves is a mixture distribution. The non-differentiability of traffic dynamics around stationary shock waves is also proved and the resulting optimality loss of the estimates is quantified numerically. The properties of the estimates are explicitly studied for the Godunov scheme (and thus the Cell-Transmission Model), leading to specific conclusions about their use in the context of filtering, which is a significant contribution of this article. Analytical proofs and numerical tests are introduced to support the results presented. A Java implementation of the classical filters used in this work is available on-line at http://traffic.berkeley.edu for facilitating further efforts on this topic and fostering reproducible research.

  12. Traffic Volume and Aggregate Economic Activity: Implications for Taking the Pulse of the U.S. Economy

    DOT National Transportation Integrated Search

    2016-09-01

    What is the incremental relevance of real-time traffic volume data for taking the pulse of the U.S. economy? Although prior research has identified a positive link between traffic volume and economic activity, there is a dearth of evidence on the rel...

  13. 75 FR 5261 - Waybill Data Reporting for Toxic Inhalation Hazards

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-02

    ... monitor traffic flows and rate trends in the industry, and to develop evidence in Board proceedings. The... submitted to include all traffic movements designated as a TIH (Toxic Inhalation Hazard). The revised... Board to assess more accurately TIH traffic within the United States, and specifically would be...

  14. Simulation of the air traffic control radar beacon system (soar) with application to a discrete address beacon system volume II: appendixes

    DOT National Transportation Integrated Search

    1975-04-01

    The report describes a computer simulation of the Air Traffic Control Radar Beacon System (ATCRBS). Operating on real air traffic data and actual characteristics of the relevant ground interrogators, the FORTRAN program re-enacts system operation in ...

  15. 32 CFR 250.8 - Pertinent portions of International Traffic in Arms Regulations (ITAR).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Arms Regulations (ITAR). 250.8 Section 250.8 National Defense Department of Defense (Continued) OFFICE... PUBLIC DISCLOSURE § 250.8 Pertinent portions of International Traffic in Arms Regulations (ITAR). The... releasibility of technical data under the authority of this part. International Traffic in Arms Regulations 22...

  16. 32 CFR 250.8 - Pertinent portions of International Traffic in Arms Regulations (ITAR).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Arms Regulations (ITAR). 250.8 Section 250.8 National Defense Department of Defense (Continued) OFFICE... PUBLIC DISCLOSURE § 250.8 Pertinent portions of International Traffic in Arms Regulations (ITAR). The... releasibility of technical data under the authority of this part. International Traffic in Arms Regulations 22...

  17. Simulation of the Air Traffic Control Radar Beacon System (SOAR) with application to a Discrete Address Beacon System. Volume 1 : text

    DOT National Transportation Integrated Search

    1975-04-01

    The report describes a computer simulation of the Air Traffic Control Radar Beacon System (ATCRBS). Operating on real air traffic data and actual characteristics of the relevant ground interrogators, the FORTRAN program re-enacts system operation in ...

  18. Traffic experiment reveals the nature of car-following.

    PubMed

    Jiang, Rui; Hu, Mao-Bin; Zhang, H M; Gao, Zi-You; Jia, Bin; Wu, Qing-Song; Wang, Bing; Yang, Ming

    2014-01-01

    As a typical self-driven many-particle system far from equilibrium, traffic flow exhibits diverse fascinating non-equilibrium phenomena, most of which are closely related to traffic flow stability and specifically the growth/dissipation pattern of disturbances. However, the traffic theories have been controversial due to a lack of precise traffic data. We have studied traffic flow from a new perspective by carrying out large-scale car-following experiment on an open road section, which overcomes the intrinsic deficiency of empirical observations. The experiment has shown clearly the nature of car-following, which runs against the traditional traffic flow theory. Simulations show that by removing the fundamental notion in the traditional car-following models and allowing the traffic state to span a two-dimensional region in velocity-spacing plane, the growth pattern of disturbances has changed qualitatively and becomes qualitatively or even quantitatively in consistent with that observed in the experiment.

  19. Traffic Experiment Reveals the Nature of Car-Following

    PubMed Central

    Jiang, Rui; Hu, Mao-Bin; Zhang, H. M.; Gao, Zi-You; Jia, Bin; Wu, Qing-Song; Wang, Bing; Yang, Ming

    2014-01-01

    As a typical self-driven many-particle system far from equilibrium, traffic flow exhibits diverse fascinating non-equilibrium phenomena, most of which are closely related to traffic flow stability and specifically the growth/dissipation pattern of disturbances. However, the traffic theories have been controversial due to a lack of precise traffic data. We have studied traffic flow from a new perspective by carrying out large-scale car-following experiment on an open road section, which overcomes the intrinsic deficiency of empirical observations. The experiment has shown clearly the nature of car-following, which runs against the traditional traffic flow theory. Simulations show that by removing the fundamental notion in the traditional car-following models and allowing the traffic state to span a two-dimensional region in velocity-spacing plane, the growth pattern of disturbances has changed qualitatively and becomes qualitatively or even quantitatively in consistent with that observed in the experiment. PMID:24740284

  20. Minimal-delay traffic grooming for WDM star networks

    NASA Astrophysics Data System (ADS)

    Choi, Hongsik; Garg, Nikhil; Choi, Hyeong-Ah

    2003-10-01

    All-optical networks face the challenge of reducing slower opto-electronic conversions by managing assignment of traffic streams to wavelengths in an intelligent manner, while at the same time utilizing bandwidth resources to the maximum. This challenge becomes harder in networks closer to the end users that have insufficient data to saturate single wavelengths as well as traffic streams outnumbering the usable wavelengths, resulting in traffic grooming which requires costly traffic analysis at access nodes. We study the problem of traffic grooming that reduces the need to analyze traffic, for a class of network architecture most used by Metropolitan Area Networks; the star network. The problem being NP-complete, we provide an efficient twice-optimal-bound greedy heuristic for the same, that can be used to intelligently groom traffic at the LANs to reduce latency at the access nodes. Simulation results show that our greedy heuristic achieves a near-optimal solution.

  1. Prediction based active ramp metering control strategy with mobility and safety assessment

    NASA Astrophysics Data System (ADS)

    Fang, Jie; Tu, Lili

    2018-04-01

    Ramp metering is one of the most direct and efficient motorway traffic flow management measures so as to improve traffic conditions. However, owing to short of traffic conditions prediction, in earlier studies, the impact on traffic flow dynamics of the applied RM control was not quantitatively evaluated. In this study, a RM control algorithm adopting Model Predictive Control (MPC) framework to predict and assess future traffic conditions, which taking both the current traffic conditions and the RM-controlled future traffic states into consideration, was presented. The designed RM control algorithm targets at optimizing the network mobility and safety performance. The designed algorithm is evaluated in a field-data-based simulation. Through comparing the presented algorithm controlled scenario with the uncontrolled scenario, it was proved that the proposed RM control algorithm can effectively relieve the congestion of traffic network with no significant compromises in safety aspect.

  2. From empirical Bayes to full Bayes : methods for analyzing traffic safety data.

    DOT National Transportation Integrated Search

    2004-10-24

    Traffic safety engineers are among the early adopters of Bayesian statistical tools for : analyzing crash data. As in many other areas of application, empirical Bayes methods were : their first choice, perhaps because they represent an intuitively ap...

  3. Development, validation, and fairness of a biographical data questionnaire for the air traffic control specialist occupation.

    DOT National Transportation Integrated Search

    2012-12-01

    Development and validation of a biographical data (biodata) instrument for selection into the Air Traffic : Control Specialist occupation is described. Bootstrapping was used to estimate correlations between item : responses to the Applicant Ba...

  4. Incremental Validity of Biographical Data in the Prediction of En Route Air Traffic Control Specialist Technical Skills

    DOT National Transportation Integrated Search

    2012-07-01

    Previous research demonstrated that an empirically-keyed, response-option scored biographical data (biodata) : scale predicted supervisory ratings of air traffic control specialist (ATCS) job performance (Dean & Broach, : 2011). This research f...

  5. Data mining of air traffic control operational errors

    DOT National Transportation Integrated Search

    2006-01-01

    In this paper we present the results of : applying data mining techniques to identify patterns and : anomalies in air traffic control operational errors (OEs). : Reducing the OE rate is of high importance and remains a : challenge in the aviation saf...

  6. Evaluation of TxDOT'S traffic data collection and load forecasting process

    DOT National Transportation Integrated Search

    2001-01-01

    This study had two primary objectives: (1) compare current Texas Department of Transportation (TxDOT) procedures and protocols with the state-of-the-practice and the needs of its data customers; and (2) develop enhanced traffic collection, archival, ...

  7. Development of traffic data input resources for the mechanistic empirical pavement design process.

    DOT National Transportation Integrated Search

    2011-12-12

    The Mechanistic-Empirical Pavement Design Guide (MEPDG) for New and Rehabilitated Pavement Structures uses : nationally based data traffic inputs and recommends that state DOTs develop their own site-specific and regional : values. To support the MEP...

  8. Demonstration of non-intrusive traffic data collection devices in Alaska.

    DOT National Transportation Integrated Search

    2010-05-01

    The purpose of this document is to present findings from the Demonstration of Non-Intrusive Traffic Data Collection Devices in Alaska. This project was initiated by the : Alaska Department of Transportation and Public Facilities (DOT&PF) to evaluate ...

  9. Vehicle aggressivity : fleet characterization using traffic collision data

    DOT National Transportation Integrated Search

    1998-02-01

    The objective of this study was to determine the crashworthiness and aggressivity of passenger cars, light trucks and vans (LTVs) in traffic collisions. The data for the analysis was taken from the NHTSA Fatal Analysis Reporting System (FARS) and the...

  10. Minnesota urban partnership agreement national evaluation : traffic system data test plan.

    DOT National Transportation Integrated Search

    2009-11-17

    This report presents the traffic system data test plan for the Minnesota Urban Partnership Agreement (UPA) under the United States Department of Transportation (U.S. DOT) UPA Program. The Minnesota UPA projects focus on reducing congestion by employi...

  11. Analysis of traffic accident data in Kentucky (1994-1998)

    DOT National Transportation Integrated Search

    1999-09-01

    This report includes an analysis of traffic accident data in Kentucky for the years of 1994 through 1998. A primary objective of this study was to determine average accident statistics for Kentucky highways. Average and critical numbers and rates of ...

  12. Analysis of traffic crash data in Kentucky : 2002-2006.

    DOT National Transportation Integrated Search

    2007-09-01

    This report includes an analysis of traffic accident data in Kentucky for the years of 2002 through 2006. A primary objective of this study was to determine average accident statistics for Kentucky highways. Average and critical numbers and rates of ...

  13. Analysis of traffic crash data in Kentucky : 2003-2007.

    DOT National Transportation Integrated Search

    2008-08-01

    This report includes an analysis of traffic accident data in Kentucky for the years of 2003 through 2007. A primary objective of this study was to determine average accident statistics for Kentucky highways. Average and critical numbers and rates of ...

  14. Evaluation of the ADAPTIR System for Work Zone Traffic Control

    DOT National Transportation Integrated Search

    1999-11-01

    The ADAPTIR system (Automated Data Acquisition and Processing of Traffic Information in Real Time) uses variable message signs (VMS) equipped with radar units, along with a software program to interpret the data, to display appropriate warning and ad...

  15. Network traffic behaviour near phase transition point

    NASA Astrophysics Data System (ADS)

    Lawniczak, A. T.; Tang, X.

    2006-03-01

    We explore packet traffic dynamics in a data network model near phase transition point from free flow to congestion. The model of data network is an abstraction of the Network Layer of the OSI (Open Systems Interconnect) Reference Model of packet switching networks. The Network Layer is responsible for routing packets across the network from their sources to their destinations and for control of congestion in data networks. Using the model we investigate spatio-temporal packets traffic dynamics near the phase transition point for various network connection topologies, and static and adaptive routing algorithms. We present selected simulation results and analyze them.

  16. Vision-Based Traffic Data Collection Sensor for Automotive Applications

    PubMed Central

    Llorca, David F.; Sánchez, Sergio; Ocaña, Manuel; Sotelo, Miguel. A.

    2010-01-01

    This paper presents a complete vision sensor onboard a moving vehicle which collects the traffic data in its local area in daytime conditions. The sensor comprises a rear looking and a forward looking camera. Thus, a representative description of the traffic conditions in the local area of the host vehicle can be computed. The proposed sensor detects the number of vehicles (traffic load), their relative positions and their relative velocities in a four-stage process: lane detection, candidates selection, vehicles classification and tracking. Absolute velocities (average road speed) and global positioning are obtained after combining the outputs provided by the vision sensor with the data supplied by the CAN Bus and a GPS sensor. The presented experiments are promising in terms of detection performance and accuracy in order to be validated for applications in the context of the automotive industry. PMID:22315572

  17. Vision-based traffic data collection sensor for automotive applications.

    PubMed

    Llorca, David F; Sánchez, Sergio; Ocaña, Manuel; Sotelo, Miguel A

    2010-01-01

    This paper presents a complete vision sensor onboard a moving vehicle which collects the traffic data in its local area in daytime conditions. The sensor comprises a rear looking and a forward looking camera. Thus, a representative description of the traffic conditions in the local area of the host vehicle can be computed. The proposed sensor detects the number of vehicles (traffic load), their relative positions and their relative velocities in a four-stage process: lane detection, candidates selection, vehicles classification and tracking. Absolute velocities (average road speed) and global positioning are obtained after combining the outputs provided by the vision sensor with the data supplied by the CAN Bus and a GPS sensor. The presented experiments are promising in terms of detection performance and accuracy in order to be validated for applications in the context of the automotive industry.

  18. Trip-oriented travel time prediction (TOTTP) with historical vehicle trajectories

    NASA Astrophysics Data System (ADS)

    Xu, Tao; Li, Xiang; Claramunt, Christophe

    2018-06-01

    Accurate travel time prediction is undoubtedly of importance to both traffic managers and travelers. In highly-urbanized areas, trip-oriented travel time prediction (TOTTP) is valuable to travelers rather than traffic managers as the former usually expect to know the travel time of a trip which may cross over multiple road sections. There are two obstacles to the development of TOTTP, including traffic complexity and traffic data coverage.With large scale historical vehicle trajectory data and meteorology data, this research develops a BPNN-based approach through integrating multiple factors affecting trip travel time into a BPNN model to predict trip-oriented travel time for OD pairs in urban network. Results of experiments demonstrate that it helps discover the dominate trends of travel time changes daily and weekly, and the impact of weather conditions is non-trivial.

  19. Key Technology of Real-Time Road Navigation Method Based on Intelligent Data Research

    PubMed Central

    Tang, Haijing; Liang, Yu; Huang, Zhongnan; Wang, Taoyi; He, Lin; Du, Yicong; Ding, Gangyi

    2016-01-01

    The effect of traffic flow prediction plays an important role in routing selection. Traditional traffic flow forecasting methods mainly include linear, nonlinear, neural network, and Time Series Analysis method. However, all of them have some shortcomings. This paper analyzes the existing algorithms on traffic flow prediction and characteristics of city traffic flow and proposes a road traffic flow prediction method based on transfer probability. This method first analyzes the transfer probability of upstream of the target road and then makes the prediction of the traffic flow at the next time by using the traffic flow equation. Newton Interior-Point Method is used to obtain the optimal value of parameters. Finally, it uses the proposed model to predict the traffic flow at the next time. By comparing the existing prediction methods, the proposed model has proven to have good performance. It can fast get the optimal value of parameters faster and has higher prediction accuracy, which can be used to make real-time traffic flow prediction. PMID:27872637

  20. An Efficient Method of Sharing Mass Spatio-Temporal Trajectory Data Based on Cloudera Impala for Traffic Distribution Mapping in an Urban City.

    PubMed

    Zhou, Lianjie; Chen, Nengcheng; Yuan, Sai; Chen, Zeqiang

    2016-10-29

    The efficient sharing of spatio-temporal trajectory data is important to understand traffic congestion in mass data. However, the data volumes of bus networks in urban cities are growing rapidly, reaching daily volumes of one hundred million datapoints. Accessing and retrieving mass spatio-temporal trajectory data in any field is hard and inefficient due to limited computational capabilities and incomplete data organization mechanisms. Therefore, we propose an optimized and efficient spatio-temporal trajectory data retrieval method based on the Cloudera Impala query engine, called ESTRI, to enhance the efficiency of mass data sharing. As an excellent query tool for mass data, Impala can be applied for mass spatio-temporal trajectory data sharing. In ESTRI we extend the spatio-temporal trajectory data retrieval function of Impala and design a suitable data partitioning method. In our experiments, the Taiyuan BeiDou (BD) bus network is selected, containing 2300 buses with BD positioning sensors, producing 20 million records every day, resulting in two difficulties as described in the Introduction section. In addition, ESTRI and MongoDB are applied in experiments. The experiments show that ESTRI achieves the most efficient data retrieval compared to retrieval using MongoDB for data volumes of fifty million, one hundred million, one hundred and fifty million, and two hundred million. The performance of ESTRI is approximately seven times higher than that of MongoDB. The experiments show that ESTRI is an effective method for retrieving mass spatio-temporal trajectory data. Finally, bus distribution mapping in Taiyuan city is achieved, describing the buses density in different regions at different times throughout the day, which can be applied in future studies of transport, such as traffic scheduling, traffic planning and traffic behavior management in intelligent public transportation systems.

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

    PubMed

    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.

  2. Development of a real-time crash risk prediction model incorporating the various crash mechanisms across different traffic states.

    PubMed

    Xu, Chengcheng; Wang, Wei; Liu, Pan; Zhang, Fangwei

    2015-01-01

    This study aimed to identify the traffic flow variables contributing to crash risks under different traffic states and to develop a real-time crash risk model incorporating the varying crash mechanisms across different traffic states. The crash, traffic, and geometric data were collected on the I-880N freeway in California in 2008 and 2009. This study considered 4 different traffic states in Wu's 4-phase traffic theory. They are free fluid traffic, bunched fluid traffic, bunched congested traffic, and standing congested traffic. Several different statistical methods were used to accomplish the research objective. The preliminary analysis showed that traffic states significantly affected crash likelihood, collision type, and injury severity. Nonlinear canonical correlation analysis (NLCCA) was conducted to identify the underlying phenomena that made certain traffic states more hazardous than others. The results suggested that different traffic states were associated with various collision types and injury severities. The matching of traffic flow characteristics and crash characteristics in NLCCA revealed how traffic states affected traffic safety. The logistic regression analyses showed that the factors contributing to crash risks were quite different across various traffic states. To incorporate the varying crash mechanisms across different traffic states, random parameters logistic regression was used to develop a real-time crash risk model. Bayesian inference based on Markov chain Monte Carlo simulations was used for model estimation. The parameters of traffic flow variables in the model were allowed to vary across different traffic states. Compared with the standard logistic regression model, the proposed model significantly improved the goodness-of-fit and predictive performance. These results can promote a better understanding of the relationship between traffic flow characteristics and crash risks, which is valuable knowledge in the pursuit of improving traffic safety on freeways through the use of dynamic safety management systems.

  3. Development of Increasingly Autonomous Traffic Data Manager Using Pilot Relevancy and Ranking Data

    NASA Technical Reports Server (NTRS)

    Le Vie, Lisa R.; Houston, Vincent E.

    2017-01-01

    NASA's Safe Autonomous Systems Operations (SASO) project goal is to define and safely enable all future airspace operations by justifiable and optimal autonomy for advanced air, ground, and connected capabilities. This work showcases how Increasingly Autonomous Systems (IAS) could create operational transformations beneficial to the enhancement of civil aviation safety and efficiency. One such IAS under development is the Traffic Data Manager (TDM). This concept is a prototype 'intelligent party-line' system that would declutter and parse out non-relevant air traffic, displaying only relevant air traffic to the aircrew in a digital data communications (Data Comm) environment. As an initial step, over 22,000 data points were gathered from 31 Airline Transport Pilots to train the machine learning algorithms designed to mimic human experts and expertise. The test collection used an analog of the Navigation Display. Pilots were asked to rate the relevancy of the displayed traffic using an interactive tablet application. Pilots were also asked to rank the order of importance of the information given, to better weight the variables within the algorithm. They were also asked if the information given was enough data, and more importantly the "right" data to best inform the algorithm. The paper will describe the findings and their impact to the further development of the algorithm for TDM and, in general, address the issue of how can we train supervised machine learning algorithms, critical to increasingly autonomous systems, with the knowledge and expertise of expert human pilots.

  4. Design and implementation of a telecommunication interface for the TAATM/TCV real-time experiment

    NASA Technical Reports Server (NTRS)

    Nolan, J. D.

    1981-01-01

    The traffic situation display experiment of the terminal configured vehicle (TCV) research program requires a bidirectional data communications tie line between an computer complex. The tie line is used in a real time environment on the CYBER 175 computer by the terminal area air traffic model (TAATM) simulation program. Aircraft position data are processed by TAATM with the resultant output sent to the facility for the generation of air traffic situation displays which are transmitted to a research aircraft.

  5. Future Air Traffic Growth and Schedule Model, Supplement

    NASA Technical Reports Server (NTRS)

    Kimmel, William M. (Technical Monitor); Smith, Jeremy C.; Dollyhigh, Samuel M.

    2004-01-01

    The Future Air Traffic Growth and Schedule Model was developed as an implementation of the Fratar algorithm to project future traffic flow between airports in a system and of then scheduling the additional flights to reflect current passenger time-of-travel preferences. The methodology produces an unconstrained future schedule from a current (or baseline) schedule and the airport operations growth rates. As an example of the use of the model, future schedules are projected for 2010 and 2022 for all flights arriving at, departing from, or flying between all continental United States airports that had commercial scheduled service for May 17, 2002. Inter-continental US traffic and airports are included and the traffic is also grown with the Fratar methodology to account for their arrivals and departures to the continental US airports. Input data sets derived from the Official Airline Guide (OAG) data and FAA Terminal Area Forecast (TAF) are included in the examples of the computer code execution.

  6. Classification of Traffic Related Short Texts to Analyse Road Problems in Urban Areas

    NASA Astrophysics Data System (ADS)

    Saldana-Perez, A. M. M.; Moreno-Ibarra, M.; Tores-Ruiz, M.

    2017-09-01

    The Volunteer Geographic Information (VGI) can be used to understand the urban dynamics. In the classification of traffic related short texts to analyze road problems in urban areas, a VGI data analysis is done over a social media's publications, in order to classify traffic events at big cities that modify the movement of vehicles and people through the roads, such as car accidents, traffic and closures. The classification of traffic events described in short texts is done by applying a supervised machine learning algorithm. In the approach users are considered as sensors which describe their surroundings and provide their geographic position at the social network. The posts are treated by a text mining process and classified into five groups. Finally, the classified events are grouped in a data corpus and geo-visualized in the study area, to detect the places with more vehicular problems.

  7. Traffic Flow Density Distribution Based on FEM

    NASA Astrophysics Data System (ADS)

    Ma, Jing; Cui, Jianming

    In analysis of normal traffic flow, it usually uses the static or dynamic model to numerical analyze based on fluid mechanics. However, in such handling process, the problem of massive modeling and data handling exist, and the accuracy is not high. Finite Element Method (FEM) is a production which is developed from the combination of a modern mathematics, mathematics and computer technology, and it has been widely applied in various domain such as engineering. Based on existing theory of traffic flow, ITS and the development of FEM, a simulation theory of the FEM that solves the problems existing in traffic flow is put forward. Based on this theory, using the existing Finite Element Analysis (FEA) software, the traffic flow is simulated analyzed with fluid mechanics and the dynamics. Massive data processing problem of manually modeling and numerical analysis is solved, and the authenticity of simulation is enhanced.

  8. A review of the effect of traffic and weather characteristics on road safety.

    PubMed

    Theofilatos, Athanasios; Yannis, George

    2014-11-01

    Taking into consideration the increasing availability of real-time traffic data and stimulated by the importance of proactive safety management, this paper attempts to provide a review of the effect of traffic and weather characteristics on road safety, identify the gaps and discuss the needs for further research. Despite the existence of generally mixed evidence on the effect of traffic parameters, a few patterns can be observed. For instance, traffic flow seems to have a non-linear relationship with accident rates, even though some studies suggest linear relationship with accidents. On the other hand, increased speed limits have found to have a straightforward positive relationship with accident occurrence. Regarding weather effects, the effect of precipitation is quite consistent and leads generally to increased accident frequency but does not seem to have a consistent effect on severity. The impact of other weather parameters on safety, such as visibility, wind speed and temperature is not found straightforward so far. The increasing use of real-time data not only makes easier to identify the safety impact of traffic and weather characteristics, but most importantly makes possible the identification of their combined effect. The more systematic use of these real-time data may address several of the research gaps identified in this research. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Discovering Knowledge from AIS Database for Application in VTS

    NASA Astrophysics Data System (ADS)

    Tsou, Ming-Cheng

    The widespread use of the Automatic Identification System (AIS) has had a significant impact on maritime technology. AIS enables the Vessel Traffic Service (VTS) not only to offer commonly known functions such as identification, tracking and monitoring of vessels, but also to provide rich real-time information that is useful for marine traffic investigation, statistical analysis and theoretical research. However, due to the rapid accumulation of AIS observation data, the VTS platform is often unable quickly and effectively to absorb and analyze it. Traditional observation and analysis methods are becoming less suitable for the modern AIS generation of VTS. In view of this, we applied the same data mining technique used for business intelligence discovery (in Customer Relation Management (CRM) business marketing) to the analysis of AIS observation data. This recasts the marine traffic problem as a business-marketing problem and integrates technologies such as Geographic Information Systems (GIS), database management systems, data warehousing and data mining to facilitate the discovery of hidden and valuable information in a huge amount of observation data. Consequently, this provides the marine traffic managers with a useful strategic planning resource.

  10. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2008

    DOT National Transportation Integrated Search

    2008-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  11. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2009

    DOT National Transportation Integrated Search

    2009-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  12. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2004

    DOT National Transportation Integrated Search

    2004-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  13. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2007

    DOT National Transportation Integrated Search

    2007-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  14. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2006

    DOT National Transportation Integrated Search

    2006-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  15. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2005

    DOT National Transportation Integrated Search

    2005-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

  16. Data Bank 28IS(FF) - T-100 International Segment Data, US Air Carriers Traffic and Capacity Data (World Area Code) - 3 Year Restricted (includes foreign point and foreign Point by US Carrier) : [2003

    DOT National Transportation Integrated Search

    2003-01-01

    This CD presents nonstop operations (segments) as reported by U.S. air carriers. These data are releasable after a 3 year confidentiality period and include U.S. Air Carrier foreign point to foreign point traffic. These data fields contain informatio...

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

    PubMed Central

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

    2016-01-01

    Background: In the present study, the epidemiologic aspects of road traffic crashes in South East of Iran are described. Methods: 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. Results: 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%). Conclusions: 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. PMID:27157159

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

    PubMed

    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.

  19. Road Traffic Anomaly Detection via Collaborative Path Inference from GPS Snippets

    PubMed Central

    Wang, Hongtao; Wen, Hui; Yi, Feng; Zhu, Hongsong; Sun, Limin

    2017-01-01

    Road traffic anomaly denotes a road segment that is anomalous in terms of traffic flow of vehicles. Detecting road traffic anomalies from GPS (Global Position System) snippets data is becoming critical in urban computing since they often suggest underlying events. However, the noisy and sparse nature of GPS snippets data have ushered multiple problems, which have prompted the detection of road traffic anomalies to be very challenging. To address these issues, we propose a two-stage solution which consists of two components: a Collaborative Path Inference (CPI) model and a Road Anomaly Test (RAT) model. CPI model performs path inference incorporating both static and dynamic features into a Conditional Random Field (CRF). Dynamic context features are learned collaboratively from large GPS snippets via a tensor decomposition technique. Then RAT calculates the anomalous degree for each road segment from the inferred fine-grained trajectories in given time intervals. We evaluated our method using a large scale real world dataset, which includes one-month GPS location data from more than eight thousand taxicabs in Beijing. The evaluation results show the advantages of our method beyond other baseline techniques. PMID:28282948

  20. A wireless sensor network for urban traffic characterization and trend monitoring.

    PubMed

    Fernández-Lozano, J J; Martín-Guzmán, Miguel; Martín-Ávila, Juan; García-Cerezo, A

    2015-10-15

    Sustainable mobility requires a better management of the available infrastructure resources. To achieve this goal, it is necessary to obtain accurate data about road usage, in particular in urban areas. Although a variety of sensor alternates for urban traffic exist, they usually require extensive investments in the form of construction works for installation, processing means, etc. Wireless Sensor Networks (WSN) are an alternative to acquire urban traffic data, allowing for flexible, easy deployment. Together with the use of the appropriate sensors, like Bluetooth identification, and associate processing, WSN can provide the means to obtain in real time data like the origin-destination matrix, a key tool for trend monitoring which previously required weeks or months to be completed. This paper presents a system based on WSN designed to characterize urban traffic, particularly traffic trend monitoring through the calculation of the origin-destination matrix in real time by using Bluetooth identification. Additional sensors are also available integrated in different types of nodes. Experiments in real conditions have been performed, both for separate sensors (Bluetooth, ultrasound and laser), and for the whole system, showing the feasibility of this approach.

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