GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Mobility and traffic research  (16)
  • 1
    Online Resource
    Online Resource
    Evaluating the Effects of Signal Countdown Timers on Queue Discharge Characteristics at Signalized Intersections in China
    SAGE Publications ; 2012
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2286, No. 1 ( 2012-01), p. 39-48
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2286, No. 1 ( 2012-01), p. 39-48
    Abstract: A study evaluated the effects of signal countdown timers on queue discharge characteristics of protected left-turn and through movements at signalized intersections in China. Using data collected from 13 approaches at seven signalized intersections, the research team evaluated the effects of countdown timers on saturation headways and start-up lost time for both through and protected left-turn movements. Countdown timers had a positive but generally limited impact on the capacity of signalized intersections. Signal countdown timers significantly affected driver starting response time and start-up lost time for both protected left-turn and through movements. On average, countdown timers reduced the start-up lost time by 0.6 s per cycle for protected left-turn movements and 2.25 s per cycle for through movements at selected sites. Signal countdown timers had little effect on saturation headways. On average, signal countdown timers resulted in a saturation headway 0.11 s higher for protected left-turn movements and a saturation headway 0.15 s higher for through movements at selected sites. The difference in saturation headways was statistically significant for through movements, but not for left-turn movements. The study also looked extensively at the impact of countdown timers on the compression of discharge headways at the end of each queue. The presence of countdown timers resulted in headway compressions at the end of each queue. For protected left-turn movements, headway compression usually started when 5 s remain in the left-turn green arrow time. For through movements, headway compression may start as early as when 14 s remain in the green time.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2286-05
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2012
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Urban Travel Time Reliability Analysis with Consumer GPS Data
    SAGE Publications ; 2015
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2497, No. 1 ( 2015-01), p. 73-83
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2497, No. 1 ( 2015-01), p. 73-83
    Abstract: This study explored the use of commercially available consumer GPS data in travel time reliability analyses. Specifically, speed profiles provided by TomTom, Inc., were used to obtain travel time statistics (i.e., means and variances) on nonexpressway road segments in the Chicago, Illinois, metropolitan area. Travel time distributions were then derived for these road segments to complement those obtained from conventional expressway traffic sensor data. The analysis of travel time reliability was based on the theory of stochastic dominance, which attempted to capture the commonality of all individuals who had similar risk-taking preferences. A case study built on this new data source was used to examine ( a) how risk-taking preferences (risk neutrality, risk aversion, and ruin aversion) would lead to different admissible path sets and ( b) how the new data sources would affect the results of travel time reliability analysis.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2497-08
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2015
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Factors Affecting Driver Injury Severity in the Wrong-Way Crash: Accounting for Potential Heterogeneity in Means and Variances of Random Parameters
    SAGE Publications ; 2021
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2675, No. 9 ( 2021-09), p. 1720-1729
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2675, No. 9 ( 2021-09), p. 1720-1729
    Abstract: Because of the high percentage of fatalities and severe injuries in wrong-way driving (WWD) crashes, numerous studies have focused on identifying contributing factors to the occurrence of WWD crashes. However, a limited number of research effort has investigated the factors associated with driver injury-severity in WWD crashes. This study intends to bridge the gap using a random parameter logit model with heterogeneity in means and variances approach that can account for the unobserved heterogeneity in the data set. Police-reported crash data collected from 2014 to 2017 in North Carolina are used. Four injury-severity levels are defined: fatal injury, severe injury, possible injury, and no injury. Explanatory variables, including driver characteristics, roadway characteristics, environmental characteristics, and crash characteristics, are used. Estimation results demonstrate that factors, including the involvement of alcohol, rural area, principal arterial, high speed limit ( 〉 60 mph), dark-lighted conditions, run-off-road collision, and head-on collision, significantly increase the severity levels in WWD crashes. Several policy implications are designed and recommended based on findings.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981211009882
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2021
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Factors Associated With the Severity of Motor Vehicle Crashes Involving Electric Motorcycles and Electric Bicycles: A Random Parameters Logit Approach With Heterogeneity in Means
    SAGE Publications ; 2023
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2677, No. 8 ( 2023-08), p. 691-704
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2677, No. 8 ( 2023-08), p. 691-704
    Abstract: Exploring the heterogeneity of factors influencing the severity of electric bicycle crashes and electric motorcycle crashes can help target accident prevention policies to improve traffic safety. Therefore, this paper establishes a mean heterogeneity random parameter logit model using crash data from 2016 to 2020 in Guangxi to explore the different factors influencing the severity of crashes involving electric motorcycles and electric bicycles. The results show that the key influences on crash severity differ in electric motorcycle crashes and electric bicycle crashes. At the same time, some common factors affect the two types of crashes to different degrees. In addition, the complex interaction effects of unobserved heterogeneity were considered to explore the random parameters of the two types of crashes. The effect of unobserved heterogeneity on the distribution characteristics of the random parameters was then determined. For example, in electric motorcycle crashes, street lighting at night has a random parameter characteristic. The likelihood of serious crashes decreased when both street lighting at night and vehicle left turn were involved, and decreased when both street lighting at night and no signal control were involved. In electric bicycle crashes, large trucks have a random parameter characteristic. The likelihood of serious crashes increased when both large trucks and motor vehicle lights not turned on were involved, and increased when both large trucks and visibility less than or equal to 200 meters were involved. The results provide a basis for improving the road safety of electric motorcycles and electric bicycles.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981231157716
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2023
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Choice Behavior and Diffusion Impact Analysis of Connected and Autonomous Vehicle Travelers with Managed Lanes
    SAGE Publications ; 2024
    In:  Transportation Research Record: Journal of the Transportation Research Board
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications
    Abstract: With the accelerated integration of connected and autonomous vehicles (CAVs) into transportation systems, such vehicles have evolved rapidly. Emerging studies have focused on the considerations influencing travelers’ acceptance of CAVs and the factors contributing to travel choice intention. However, the different reasons for the diffusion of CAVs and the associated trends in relation to this are key questions that still require investigation. Therefore, this study establishes a structural equation modeling (SEM) framework to explore the impact of both external factors and internal subjective factors on travel choice. Based on the influencing factors identified by SEM, this study develops an agent-based model simulation approach to examine the diffusion trends in relation to CAV travelers from an individual perspective. To calibrate the model, a questionnaire survey is designed to obtain data from travelers in Shenzhen, Guangdong Province, China. The survey results show that CAV choice intention is influenced by individual (including innovativeness), travel-related, and social influence factors. The simulation experiments reveal that the diffusion of CAV travelers is a complex process. The lower cost of CAV travel has a positive impact initially and midway through the process of diffusion in relation to CAV users. For example, in situations in which CAVs are more cost-effective, during the simulation time (years) the number of CAV users fluctuates significantly between the 7th and 30th years. There is a notable increase of 10% in CAV users in the 15th year and, eventually, the total number of CAV users stabilizes at 71.8% of all travelers. The findings will assist agencies and CAV operators to implement effective promotion strategies.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981241231967
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2024
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Characterization of Trip-Level Pace Variability Based on Taxi GPS Trajectory Data
    SAGE Publications ; 2017
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2667, No. 1 ( 2017-01), p. 51-60
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2667, No. 1 ( 2017-01), p. 51-60
    Abstract: Travel behavior researchers have observed that the average and standard deviations of trip pace (the inverse of speed) are linearly related. This paper further studies this relationship by using taxi GPS trajectory data collected in the city of Shenzhen, China, in eight periods between early 2013 and late 2015. When tested against the original linear relationship, the data demonstrated heteroscedasticity. To address that issue, a distance- or time-corrected variable was introduced into the original linear model. The resulting two models, along with the original linear model, were tested and compared. The results showed that ( a) the new linear model with the time-corrected pace variable (TCPV) demonstrated the best fit to data compared with the other models, ( b) the parameters of the TCPV model showed strong consistency for trips originating from similar areas with similar land use patterns, and ( c) the parameters of the TCPV model were relatively stable across different time periods.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2667-06
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2017
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Multistate Nonhomogeneous Semi-Markov Model of Daily Activity Type, Timing, and Duration Sequence
    SAGE Publications ; 2009
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2134, No. 1 ( 2009-01), p. 123-134
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2134, No. 1 ( 2009-01), p. 123-134
    Abstract: Understanding travelers’ daily travel activity pattern formation is an important issue for activity-based travel-demand analysis. The activity pattern formation concerns not only complex interrelations between household members and individuals’ sociodemographic characteristics but also urban form and transport system settings. To investigate the effects of these attributes and the interrelationship between conducted activities, a multistate semi-Markov model is applied. The underlying assumption of the proposed model is that the state transition probability depends on its adjoining states. The statistical tests of significance affirm that the duration of activity depends not only on its beginning time of day but also on the duration of travel or activity previously conducted. An empirical study based on the Belgian mobility survey is conducted to estimate individuals’ daily activity durations of different episodes and provides useful insight for the effects of sociodemographic characteristics, urban and transportation system settings on the activity pattern formation.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2134-15
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2009
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Trajectory Planning for Connected and Autonomous Vehicles at Freeway Work Zones under Mixed Traffic Environment
    SAGE Publications ; 2022
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2676, No. 10 ( 2022-10), p. 207-219
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2676, No. 10 ( 2022-10), p. 207-219
    Abstract: Mixed traffic control with connected and autonomous vehicles (CAVs) and human driving vehicles (HVs) is becoming a hot topic. CAV trajectory planning at work zones under the mixed traffic environment is a big challenge. Existing studies only focus on longitudinal trajectories (e.g., acceleration profiles), ignoring lateral trajectories (lane changing). This study proposes a trajectory planning model for CAVs at work zones under mixed traffic environment. Both longitudinal and lateral trajectories are considered. On the basis of the states of CAVs and of HVs observed by CAVs, the number and initial states of unobservable HVs in the planning horizon are estimated considering the interactions between vehicle driving behaviors. A trajectory planning model is then formulated to optimize acceleration profiles and lane choices of CAVs in the planning horizon in a centralized way. The minimization of total vehicle delay and fuel consumption is adopted as the objective function. A car-following model and a lane-changing model are adopted to capture the driving behaviors of HVs. The proposed model is a mixed-integer linear program. Numerical studies validate the advantages of the proposed trajectory planning model over late merge control for vehicle delay and fuel consumption.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981221088766
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2022
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Dynamic System Optimal Routing in Multimodal Transit Network
    SAGE Publications ; 2013
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2351, No. 1 ( 2013-01), p. 76-84
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2351, No. 1 ( 2013-01), p. 76-84
    Abstract: The system optimal routing problem has been widely studied for road networks, though less considered for public transit systems. Traditional shortest path–based multimodal itinerary guidance systems may deteriorate the system performance when the assigned lines become congested. The dynamic system optimal routing model for multimodal transit system is formulated for that issue. The transit system is represented by a multilevel graph to explicitly simulate passenger flow and transit system operations. A solution algorithm based on the cross entropy method is proposed, and its performance is compared with the method of successive averages in static and dynamic cases. A numerical study of a simple multimodal transit network provides the basis for comparing system optimal routing and user optimal routing under different congestion levels.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2351-09
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2013
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Driver Back-Tracing Based on Automated Vehicle Identification Data
    SAGE Publications ; 2019
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2673, No. 6 ( 2019-06), p. 84-93
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2673, No. 6 ( 2019-06), p. 84-93
    Abstract: Traffic congestion causes traveler delay, environmental deterioration, and economic loss. Most studies on congestion mitigation focus on attracting travelers to public transportation and expanding road capacity. Few studies have been found to analyze the contribution of different traffic flows to the congestion on roads of interest. This study proposes an approach to driver back-tracing on the basis of automated vehicle identification (AVI) data for congestion mitigation. Driver back-tracing (DBT) aims to estimate the sources of the vehicles on roads of interest in both spatial and temporal dimensions. The spatial DBT model identifies the origins of vehicles on the roads and the temporal DBT model estimates the travel time from the origins to the roads. The difficulty lies in that vehicle trajectories are incomplete because of the low coverage of AVI detectors. Deep neural network classification and regression are applied to the spatial and temporal DBT models, respectively. Simulation data from VISSIM are collected as the dataset because of the lack of field data. Numerical studies validate the promising application and advantages of deep neural networks for the DBT problems. Sensitivity analyses show that the proposed models are robust to traffic volumes. However, turning ratios, and the number and layout of AVI detectors may have noticeable impacts on the model performance.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/0361198119844454
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2019
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...