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  (8)
  • 1
    Online Resource
    Online Resource
    How Built Environment Impacts Online Car-Hailing Ridership
    SAGE Publications ; 2020
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2674, No. 8 ( 2020-08), p. 745-760
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2674, No. 8 ( 2020-08), p. 745-760
    Abstract: Extensive research has shown that unilateral optimization of transit systems is not effective enough to significantly increase its transport efficiency. Considering that urban land-use characteristics, including residential, work, consumption, transit, and so forth, are significantly interrelated with travel demands and travel behaviors, this paper provides a way to optimize transit system by raising awareness of the relation between ridership and built environment. This paper adopted point of interest (POI) data to investigate the effect of physical built environment on online car-hailing ridership in Chengdu, China. The study area was tessellated with several Voronoi cells; these cells were further clustered into three ridership patterns based on the time-varying characteristic of ridership. Given that some differences existed in the three ridership patterns, a separate spatial ridership model was developed to understand the factors that influence ridership patterns using geographic weighted regression (GWR) analysis. The data and results verified that the built environment had various influences on online car-hailing alighting ridership in spatial and temporal dimensions, of which the significant POI factors for determining the ridership pattern during different periods were detected. Remarkably, this study took the ridership dataset from the online car-hailing transit system, mainly because the pick-up (PU) and drop-off (DO) locations generated by this service are closest to the origin and destination of the trip, except that it is more popular recently. Therefore, the analysis of the impact of built environment on travel based on the online car-hailing dataset can be captured in greater detail, with a higher degree of accuracy.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/0361198120924630
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2020
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Characteristics of Traffic Crashes on Freeways in China : Case Study of Jingjintang Expressway
    SAGE Publications ; 2007
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2038, No. 1 ( 2007-01), p. 148-155
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2038, No. 1 ( 2007-01), p. 148-155
    Abstract: As China feverishly builds one of the largest freeway systems in the world to meet its ever-increasing demand for highway transportation–stimulated by the unprecedented economic boom–traffic safety has become a serious concern. The problem of more than 100,000 annual traffic fatalities is threatening the country's sustainable economic development. The significant differences in road user behavior, level of motorization, traffic enforcement practice, roadside design criteria, and economic development stage make the characteristics of traffic crashes in China somewhat different from those in developed countries. To reduce traffic crashes it is important to investigate what, when, how, and why those crashes occurred. This paper introduces a highway safety project conducted on Jingjintang Expressway, one of the first freeways built in China. Results of the study show that, among other factors, the speed differential between cars and large vehicles is a main cause of high crash fatalities, particularly for rear-end collisions. The lack of real-time enforcement, problematic driver behavior, and substandard roadside design, as well as overloaded trucks all contribute heavily to traffic crashes on China's freeways.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2038-19
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2007
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Finite Element Model for Rutting Prediction of Flexible Pavement with Cementitiously Stabilized Base–Subbase
    SAGE Publications ; 2011
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2226, No. 1 ( 2011-01), p. 104-110
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2226, No. 1 ( 2011-01), p. 104-110
    Abstract: Cementitiously stabilized materials (cement-stabilized base–subbase, lime–fly ash stabilized subgrade, etc.) are widely used in roadway pavements by state agencies. Their use is a cost-efficient and environmentally friendly way to recycle industrial by-products. In the current Mechanistic–Empirical Pavement Design Guide developed under NCHRP Project 1-37A, cementitiously stabilized layers are assumed not to con-tribute to the total permanent deformation of the pavement. Such an assumption may lead to a design for an inadequate base thickness, especially when a thin asphalt concrete layer or pavements subject to heavy traffic loading are used. In this study, a unified permanent deformation model developed for various pavement materials was used to simulate the permanent deformation behavior of cementitiously stabilized materials in flexible pavements. The proposed model was implemented into the ABAQUS program through a UMAT subroutine. The finite element (FE) model was calibrated by analyzing the permanent deformation results from six accelerated pavement test sections. A shift factor of 1.13 was obtained to account for the condition differences between the laboratory permanent deformation test and the field. The FE model and the calibrated shift factor were then used to predict the rut depths of two selected low-volume roads. Good agreement was found between the predicted and measured data.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2226-11
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2011
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Safety Effects of Using Short Left-Turn Lanes at Unsignalized Median Openings
    SAGE Publications ; 2014
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2436, No. 1 ( 2014-01), p. 13-22
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2436, No. 1 ( 2014-01), p. 13-22
    Abstract: The AASHTO Green Book specifically encourages the use of left-turn lanes at median openings on divided roadways to eliminate stopping in through-traffic lanes. However, the lengths for median left-turn lanes recommended by the Green Book are often impractical in urban areas, where the available distance between two adjacent openings is inadequate, and particularly where the volume of left-turning traffic is heavy. Thus, left-turn lanes shorter than the lengths recommended by the Green Book (referred to as short left-turn lanes) are in wide use on urban divided roadways. The objective of this study was to investigate the safety performance of short left-turn lanes at unsignalized median openings. To this end, 6 years of crash data were collected in Houston, Texas, from 52 median left-turn lanes (40 short lanes and 12 lanes with lengths in compliance with Green Book recommendations). A Poisson regression model was developed to relate traffic and geometric attributes to the total number of rear-end, sideswipe, and object–motor vehicle crashes in a left-turn lane. Crash modification factors were calculated for applications to project the crash frequency for a specific change in lane length. Statistical evidence indicates that the difference between actual lane length and Green Book–recommended length has significant effects on crash frequency. However, the increase in crash frequency as a result of short left-turn lanes might be acceptable in cases where engineers must account for traffic and economic and social effects in determining whether a short left-turn lane is appropriate.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2436-02
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2014
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Data-Driven Detection and Assessment for Urban Railway Transit Driver Fatigue in Real Work Conditions
    SAGE Publications ; 2023
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2677, No. 1 ( 2023-01), p. 1367-1375
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2677, No. 1 ( 2023-01), p. 1367-1375
    Abstract: Fatigue among urban railway transit (URT) drivers affects their performance and is a contributing factor in many railway accidents and incidents. This paper attempts to develop a robust fatigue detection system for URT drivers. An experimental study was conducted in actual work conditions, involving 198 professional URT drivers, to provide authentic and representative data. Fatigue scores based on the Karolinska Sleepiness Scale were used as the ground truth, and heart rate variability (HRV) data were collected using wearable photoplethysmography (PPG) sensors under actual working conditions. An extensive statistical analysis found that continuous working hours were a major factor in driver fatigue. HRV features were able to differentiate various fatigue levels. Four classifiers (k-nearest neighbors, Naive Bayes, support vector machines, and random forests) were trained to detect fatigue in real time for binary and three-class fatigue classifications, respectively. For the binary classification, the best performance was achieved by the random forest classifier using the corrected feature set as input with an accuracy of 92.5%. However, the accuracy dropped by 8 to 27 percentage points for the three-class classification. Moreover, the research found that the corrected feature set circumventing inter-individual variability in HRV could improve the performance of fatigue classifiers. The findings from this research could contribute to developing a robust and real-time URT driver fatigue detection system and improve current URT operational safety regulations.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981221104689
    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
  • 6
    Online Resource
    Online Resource
    Prediction of User Perceptions of Signalized Intersection Level of Service Based on Fuzzy Neural Networks
    SAGE Publications ; 2009
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2130, No. 1 ( 2009-01), p. 7-15
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2130, No. 1 ( 2009-01), p. 7-15
    Abstract: Level of service (LOS) methodology incorporating user perceptions provides a measure of how well signalized intersections accommodate their users. This methodology offers new insights into signalized intersection LOS and may thus overcome the limitations of conventional delay-based methods to some extent. However, few studies on this perception-based LOS methodology have been conducted in China, where traffic conditions can be characterized by high volumes of pedestrians and bicycles. To fill the gap, this study proposes a fuzzy neural networks–based approach to predict user perceptions of signalized intersection LOS. Membership values are used to measure the perceived levels of the influential attributes that are difficult to capture accurately. A neural network containing fuzzy reasoning experiences is employed to combine the perceived attributes in order to determine LOS. To illustrate the proposed approach, a case study is performed on turning movement LOS under mixed traffic conditions. The LOS model is further calibrated and validated by using the data collected in a visualization-based survey conducted in Beijing. The numerical results indicate that the model has a favorable capability to predict user perceptions of LOS. Pearson correlation coefficients demonstrate the weak linear association between user perceptions (LOS ratings) and capacities (or volume-to-capacity ratios). Analyses of variance statistically support that users’ LOS ratings differ significantly at different levels of capacities (or volume-to-capacity ratios). The ratings depend strongly on delays. The survey results validate the delay-based method proposed by the Highway Capacity Manual to some extent.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2130-02
    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
  • 7
    Online Resource
    Online Resource
    Estimating Right-Turn-on-Red Capacity for Dual Right-Turn Lanes at Signalized Intersections
    SAGE Publications ; 2012
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2286, No. 1 ( 2012-01), p. 29-38
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2286, No. 1 ( 2012-01), p. 29-38
    Abstract: Dual right-turn lanes are increasingly used as a design alternative at urban intersections, primarily to accommodate high right-turn demand. For dual right-turn lanes, an accurate estimate of right-turn-on-red (RTOR) capacity can contribute to better decisions about whether RTOR should be allowed or prohibited and may lead to refined delay estimation and improved signal timing. A gap-acceptance model was formulated for predicting lane-specific RTOR capacities at dual right-turn lanes. The proposed model can represent the unequal effects of conflicting traffic streams from different cross-street lanes on RTOR capacities of dual right-turn lanes. Existing probabilistic methods were adapted to adjust RTOR capacity for shared through and right-turn lanes. Microsimulation models were developed, calibrated based on field data, and used as benchmarks to validate the proposed model. Numerical experiments indicated that the proposed model exhibits a significantly improved ability to predict RTOR capacities for dual right-turn lanes compared with the classical Harders model.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2286-04
    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
  • 8
    Online Resource
    Online Resource
    Evaluation of Vehicle Braking Performance on Wet Pavement Surface using an Integrated Tire-Vehicle Modeling Approach
    SAGE Publications ; 2019
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2673, No. 3 ( 2019-03), p. 295-307
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2673, No. 3 ( 2019-03), p. 295-307
    Abstract: Water film on a pavement surface greatly increases vehicle accident rates on rainy days. The simple use of a lower friction coefficient to evaluate the vehicle braking performance oversimplifies the contact mechanism between the tire and the pavement, and the use of a pure single tire model simulating hydroplaning was not able to reflect actual vehicle braking-cornering behaviors. This paper proposes an integrated tire-vehicle model to evaluate vehicle braking performance based on Persson’s friction theory, a tire hydroplaning finite element model, and a vehicle dynamic analysis. The friction coefficients between the tire and the pavement were calculated theoretically from the pavement surface morphology and the tire rubber properties; the tire hydrodynamic forces were obtained mechanistically from the hydroplaning model with different water film thicknesses and were used as inputs for calculating the braking distances in a vehicle model. The calculated friction coefficients and braking distances were verified using the field test results. A case study was conducted to illustrate the approach and evaluate the vehicle braking performance on straight and curved road sections. The results show that both longitudinal braking distances and lateral slip distances should be considered in the evaluation of vehicle braking performance.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/0361198119832886
    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...