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  (12)
Material
Publisher
Person/Organisation
Language
Years
FID
  • Mobility and traffic research  (12)
  • 1
    Online Resource
    Online Resource
    Comparison of Ballast Drainage Improvement Between Track Lifting and Shoulder Cleaning Based on CFD Simulations
    SAGE Publications ; 2023
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2677, No. 1 ( 2023-01), p. 201-211
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2677, No. 1 ( 2023-01), p. 201-211
    Abstract: Railroad track performance largely depends on ballast drainage conditions. Over the years, different ballast maintenance methods have been developed and applied in the field, aiming to restore ballast drainage capability. But the benefits from different maintenance methods have not been well quantified and compared. This study investigates and compares the benefits of the two popular ballast drainage maintenance methods used in North America, shoulder cleaning and track lifting, through numerical simulations based on computational fluid dynamics (CFD). Different fouling conditions are simulated with permeabilities quantified from the field-collected fouled ballast samples to ensure that the numerical models are representative. Because the unit cost of shoulder cleaning and track lifting varies and depends on the specific application conditions, the normalized drainage health index (NDHI) and the normalized drainage restoration ratio (NDRR) are introduced to make fair comparisons and provide unbiased parameters for practitioners to use in the future. Preliminary results from this study indicate shoulder cleaning provides better ballast drainage improvement than track lifting if the unit costs per ballast volume of shoulder cleaning and track lifting are identical.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981221098659
    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
  • 2
    Online Resource
    Online Resource
    Convolutional Neural Network with Attention Module for Identification of Tunnel Seepage
    SAGE Publications ; 2022
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2676, No. 11 ( 2022-11), p. 112-123
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2676, No. 11 ( 2022-11), p. 112-123
    Abstract: As tunnel construction proceeds ever more rapidly, the efficiency of seepage detection by engineers with expert knowledge is facing unprecedented challenges. Moreover, it suffers from strong subjectivity. In recent years, deep learning, as an algorithm of machine learning, has achieved state-of-the-art performance in pattern recognition. In this paper, we address such a problem by building convolutional neural networks that operate on conventional graphics processing units. Within the project, the data is obtained by an infrared thermal imager since there exist different characteristics of temperature between the area of seepage and non-seepage. Considering the difficulty of collecting many images, generative adversarial nets and other data augmentation skills are applicable to enlarge data sets. We design several novel architectures where the attention mechanism is plugged into various traditional models, considered as VGG16 network with Attention Module and RestNet34 with Attention Module, and the overall identification accuracy achieved is more than 97%. The codes of this project can be found at https://github.com/Scotter-Qian/cnn .
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981221091774
    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
  • 3
    Online Resource
    Online Resource
    Automatic Rail Surface Defects Inspection Based on Mask R-CNN
    SAGE Publications ; 2021
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2675, No. 11 ( 2021-11), p. 655-668
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2675, No. 11 ( 2021-11), p. 655-668
    Abstract: Rail surface defects have negative impacts on riding comfort and track safety, and could even lead to accidents. Based on the safety database (2020) of the Federal Railroad Administration (FRA), rail surface defects have been among the main factors causing derailments. During the past decades, there have been many efforts to detect such rail surface defects. However, the applications of earlier methods are limited by the high requirements of specialized equipment and personnel training. To date, rail surface defect inspection is still a very labor-intensive and time-consuming process, which hardly satisfies the field maintenance expectations. Therefore, a cost-effective and user-friendly automatic system that can inspect the rail surface defects with high accuracy is urgently needed. To address this issue, this study proposes a computer vision-based instance segmentation framework for rail surface defect inspection. A rail surface database including 1,040 images (260 source images and 780 augmented images) has been built. The classic instance segmentation model, Mask R-CNN, has been re-trained and fine-tuned for inspecting rail surface defects with the customized dataset. The influences of different backbones and learning rates are investigated and discussed. Experimental results indicate the ResNet101 backbone reaches better inspection capability. With a learning rate of 0.005, the re-trained Mask R-CNN model can achieve the best performance on the bounding box and mask predictions. Sixteen images are used to test the inspection performance of the fine-tuned model. The results are promising and indicate potential field applications in the future.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981211019034
    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
    Predicting Freeway Travel Time under Incident Conditions
    SAGE Publications ; 2010
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2178, No. 1 ( 2010-01), p. 58-66
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2178, No. 1 ( 2010-01), p. 58-66
    Abstract: Prediction of corridor travel time is essential to achieving the promise of advanced traveler information systems. Although much research has been done on travel time prediction, procedures for practical prediction of travel time under incident conditions are lacking. This paper presents a framework for online prediction of freeway corridor travel time under incident conditions on the basis of inductive loop detector and incident data. The core component is a model for prediction of corridor travel time under incident conditions that produces estimated physical queue length at various time intervals. Testing shows that the method offers enhanced accuracy in prediction of corridor travel time compared with those methods that do not consider the impact of incidents.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2178-07
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2010
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Geographic Distribution of E-Shopping : Application of Structural Equation Models in the Twin Cities of Minnesota
    SAGE Publications ; 2013
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2383, No. 1 ( 2013-01), p. 18-26
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2383, No. 1 ( 2013-01), p. 18-26
    Abstract: The proliferation of Internet shopping has imposed enormous pressure on traditional stores. Few studies have examined the geographic distribution of online buyers and its implications on retail development and transportation. Using 585 Internet users in the Minneapolis and Saint Paul, Minnesota, metropolitan area, this study develops structural equation models to test two competing hypotheses regarding the connections between spatial attributes and e-shopping: diffusion of innovation and efficiency. The results demonstrate that the influence of shopping accessibility on e-shopping is not uniform and depends on the locations in metropolitan areas. Specifically, Internet users living in urban areas, areas with greater shopping accessibility, or both tend to purchase online more often than their counterparts in other areas because the former are better educated and use the Internet more than the latter. However, low shopping accessibility in exurban areas does promote the use of e-shopping as compared with exurban areas with relatively high shopping accessibility.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2383-03
    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
  • 6
    Online Resource
    Online Resource
    Automatic Identification of Near Stationary Traffic States Using Changepoint Detection Method
    SAGE Publications ; 2022
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2676, No. 9 ( 2022-09), p. 187-201
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2676, No. 9 ( 2022-09), p. 187-201
    Abstract: Near stationary traffic states are of great significance for the calibration of the fundamental diagram and the quantification of capacity variation. In this paper, based on wavelet transform and robust functional pruning optimal partitioning (RFPOP) changepoint detection, a robust and efficient method for automatic identification of the near stationary traffic states is proposed. This method first removes the noise influence of traffic flow series, divides the series automatically into multiple candidate intervals that may be close to stationary states according to the RFPOP changepoint detection method, and calculates the candidate interval characteristics. The near stationary states are then identified based on the modified Cassidy’s criterion. A case study is provided for the proposed method, and its robustness is proved in a simulation experiment. Finally, it is shown that the method of automatic identification of near stationary traffic states proposed in this paper is robust and effective.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/03611981221086643
    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
  • 7
    Online Resource
    Online Resource
    Parking Sensing and Information System: Sensors, Deployment, and Evaluation
    SAGE Publications ; 2016
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2559, No. 1 ( 2016-01), p. 81-89
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2559, No. 1 ( 2016-01), p. 81-89
    Abstract: This paper describes a smart parking sensing and information system that disseminates parking availability information to public users in a cost-effective and efficient manner. The hardware framework of the system is built on advanced wireless sensor networks and cloud service over the Internet, and the system is highly scalable. The parking information provided to the users is set in the form of occupancy rates and expected cruising time. Both are obtained from an analytical algorithm that processes historical and real-time data and are then visualized in a color theme. The entire parking system is deployed and extensively evaluated at Stanford University, California, Parking Structure 1.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2559-10
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2016
    detail.hit.zdb_id: 2403378-9
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Performance Measurement System for Assessing Transportation Sustainability and Community Livability
    SAGE Publications ; 2015
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2531, No. 1 ( 2015-01), p. 113-120
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2531, No. 1 ( 2015-01), p. 113-120
    Abstract: Sustainability and livability as concepts that indicate the capability of transportation systems to maintain social well-being have been widely accepted as critical principles to improve the quality of life and health in communities. This study introduced a geographic information system as the basis for a performance measurement system to assess the two goals from the standpoint of transportation systems. The city of Buffalo, New York, was used as the case study. Various data were collected, and 20 sustainability and livability related performance measures (PMs), including transportation attributes, land use measures, living condition indicators, and systemwide indexes, were developed. Analysis of the PMs raised several policy implications and led to some suggestions. Lessons and challenges from the PM development process are summarized to help other relevant initiatives. The PMs, the supporting database, the case study, and the findings produced by the research are expected to help a wide range of stakeholders, including policy makers, planners, and transportation engineers, to gain more insights into transportation-oriented sustainability and livability performance measurement.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2531-13
    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
  • 9
    Online Resource
    Online Resource
    What Happens When a Major Freeway is Closed for Repair? : The Case of Fix I-5 in Downtown Sacramento, California
    SAGE Publications ; 2012
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2278, No. 1 ( 2012-01), p. 134-144
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2278, No. 1 ( 2012-01), p. 134-144
    Abstract: In the summer of 2008, a portion of Interstate 5 near downtown Sacramento, California, was closed in one direction at a time for reconstruction. The project, one of the first in California in which an entire direction of a major freeway was closed during commuting hours for planned repair work, lasted approximately 2 months and was expected to cause major congestion in the area (an area that in 2009 would be ranked in the top 49 most congested urban areas in the United States). This paper studies the actual traffic impact of the project and analyzes the behavioral and flow pattern changes that the project caused. Results showed that overall traffic demand on the freeway remained largely unchanged, with about a 3% to 7% reduction in daily traffic volume in the downtown area and less than 3% in the outskirt areas. The demand reduction during the commuting peak was more pronounced at about 7% to 12%, an indication of peak spreading. Rather than taking public transit, the majority of drivers who stayed away from the affected freeways during commuting hours chose arterial routes or earlier or later departure times. There is evidence that some drivers turned to carpooling in the initial stages of the project, but they reverted back to solo driving in the later stages. However, despite record high gas prices, vehicle volumes on the roadways returned to preconstruction levels 1 month after construction ended. This return to former volumes is an indication that people's travel habits are difficult to change in the short run.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.3141/2278-15
    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
  • 10
    Online Resource
    Online Resource
    International Roughness Index Prediction Model for Thin Hot Mix Asphalt Overlay Treatment of Flexible Pavements
    SAGE Publications ; 2018
    In:  Transportation Research Record: Journal of the Transportation Research Board Vol. 2672, No. 40 ( 2018-12), p. 7-13
    Details
    In: Transportation Research Record: Journal of the Transportation Research Board, SAGE Publications, Vol. 2672, No. 40 ( 2018-12), p. 7-13
    Abstract: Pavement performance prediction after maintenance and rehabilitation is important to pavement management. A two-parameter exponential international roughness index (IRI) regression model for thin hot mix asphalt overlay was developed based on information from the U.S. Long Term Pavement Performance (LTPP) database. The model influence parameters α and β, which represent the initial IRI as the thin overlay completion and shape factor of IRI deterioration curve, were statistically analyzed. The results suggested that the IRI deterioration trends in high-temperature and low-temperature regions are different. This is because β was mainly affected by the structural strength and equivalent single axle loads in the high and medium temperature region and mainly affected by the average annual precipitation in low temperature region. In-situ data from LTPP database was used to verify the IRI prediction model, and it was found that the predicted IRI and measured IRI exhibited similar trends.
    Type of Medium: Online Resource
    ISSN: 0361-1981 , 2169-4052
    URL: Article
    DOI: 10.1177/0361198118768522
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2018
    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...