Traffic flow forecasting plays a crucial role in the construction of intelligent transportation. The aims of this paper are to fully exploit the spatial correlation between nodes in a traffic network and to compensate for the inability of graph-based deep learning methods to model multiple relationship types, resulting in inadequate extraction of spatially correlated information about the traffic network. In this paper, we propose a deep spatio-temporal recurrent evolution network based on the graph convolution network (STREGCN) for heterogeneous graphs. Specifically, we transform the traffic network into a multi-relational heterogeneous graph to improve the information representation of the graph. This allows our model to capture multiple types of spatially relevant information. In the temporal dimension, we use one-dimensional causal convolution based on the gated linear unit to extract the temporal correlation information of the traffic flow. In addition, we designed the output of the spatio-temporal convolution module to obtain the final traffic flow predictions after a fully connected layer. Experiments on real datasets illustrate the effectiveness of the proposed STREGCN model and show the importance of representing information through heterogeneous graphs for the task of traffic flow prediction.
{"title":"Spatio-Temporal Heterogeneous Graph-Based Convolutional Networks for Traffic Flow Forecasting","authors":"Zhaobin Ma, Zhiqiang Lv, Xiaoyang Xin, Zesheng Cheng, Fengqian Xia, Jianbo Li","doi":"10.1177/03611981231213878","DOIUrl":"https://doi.org/10.1177/03611981231213878","url":null,"abstract":"Traffic flow forecasting plays a crucial role in the construction of intelligent transportation. The aims of this paper are to fully exploit the spatial correlation between nodes in a traffic network and to compensate for the inability of graph-based deep learning methods to model multiple relationship types, resulting in inadequate extraction of spatially correlated information about the traffic network. In this paper, we propose a deep spatio-temporal recurrent evolution network based on the graph convolution network (STREGCN) for heterogeneous graphs. Specifically, we transform the traffic network into a multi-relational heterogeneous graph to improve the information representation of the graph. This allows our model to capture multiple types of spatially relevant information. In the temporal dimension, we use one-dimensional causal convolution based on the gated linear unit to extract the temporal correlation information of the traffic flow. In addition, we designed the output of the spatio-temporal convolution module to obtain the final traffic flow predictions after a fully connected layer. Experiments on real datasets illustrate the effectiveness of the proposed STREGCN model and show the importance of representing information through heterogeneous graphs for the task of traffic flow prediction.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139155433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-26DOI: 10.1177/03611981231212166
Rachel F. Peterson, G. Newmark
For more than a half century, federal policy has required metropolitan planning organizations (MPOs) to communicate regional priorities through long-range transportation plans (LRTPs). Despite the length of that requirement and the high cost of the associated investments, there are virtually no resources to guide MPOs in graphically communicating these plans to the public. This research reviews 1,502 graphics from a stratified random sample of LRTPs from 20 MPOs across the United States with populations less than 200,000. Quantitative and qualitative analyses were conducted to assess current graphic practices and generate suggestions to guide MPOs in enhancing graphic communication. This review categorizes LRTP graphics into three types (spatial, numeric, and concept), identifies the frequency, components, and uses of each type, and then proposes a set of 26 “core” graphics as a common baseline for all LRTPs.
{"title":"Graphic Guidance for Long-Range Transportation Plans","authors":"Rachel F. Peterson, G. Newmark","doi":"10.1177/03611981231212166","DOIUrl":"https://doi.org/10.1177/03611981231212166","url":null,"abstract":"For more than a half century, federal policy has required metropolitan planning organizations (MPOs) to communicate regional priorities through long-range transportation plans (LRTPs). Despite the length of that requirement and the high cost of the associated investments, there are virtually no resources to guide MPOs in graphically communicating these plans to the public. This research reviews 1,502 graphics from a stratified random sample of LRTPs from 20 MPOs across the United States with populations less than 200,000. Quantitative and qualitative analyses were conducted to assess current graphic practices and generate suggestions to guide MPOs in enhancing graphic communication. This review categorizes LRTP graphics into three types (spatial, numeric, and concept), identifies the frequency, components, and uses of each type, and then proposes a set of 26 “core” graphics as a common baseline for all LRTPs.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139155010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-26DOI: 10.1177/03611981231215339
M. Schiefelbusch
To serve rural areas efficiently and effectively, public transportation must have tools suitable to serve the small-scale and dispersed mobility needs typical of countryside settings. One way of achieving this is by giving more space to locally planned and operated services, to achieve better-tailored solutions and more cost-efficient ways of service provision. In the English-speaking world, this approach is known as “community transport” (CT). In Germany, “Gemeinschaftsverkehr” (as a loose translation of community transport) is a much more recent concept, although certain elements of CT have been in use for some time. This paper synthesizes and discusses how CT has evolved and (in part) been reinterpreted in Germany over recent years, in particular in the state of Baden-Württemberg. In addition to an overview of service models, the paper discusses some more general questions linked to the idea of CT, such as the potential tensions between “top-down” and “bottom-up” views on planning, formal/regulatory challenges, and the implications of a more heterogeneous set of stakeholders. The paper is based in part on dedicated research activities, but mainly on the author’s direct involvement as consultant and policy advisor.
{"title":"Shared Responsibility for Shared Mobility: Community-Based Transportation in Germany","authors":"M. Schiefelbusch","doi":"10.1177/03611981231215339","DOIUrl":"https://doi.org/10.1177/03611981231215339","url":null,"abstract":"To serve rural areas efficiently and effectively, public transportation must have tools suitable to serve the small-scale and dispersed mobility needs typical of countryside settings. One way of achieving this is by giving more space to locally planned and operated services, to achieve better-tailored solutions and more cost-efficient ways of service provision. In the English-speaking world, this approach is known as “community transport” (CT). In Germany, “Gemeinschaftsverkehr” (as a loose translation of community transport) is a much more recent concept, although certain elements of CT have been in use for some time. This paper synthesizes and discusses how CT has evolved and (in part) been reinterpreted in Germany over recent years, in particular in the state of Baden-Württemberg. In addition to an overview of service models, the paper discusses some more general questions linked to the idea of CT, such as the potential tensions between “top-down” and “bottom-up” views on planning, formal/regulatory challenges, and the implications of a more heterogeneous set of stakeholders. The paper is based in part on dedicated research activities, but mainly on the author’s direct involvement as consultant and policy advisor.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139155895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-26DOI: 10.1177/03611981231213081
Diego Armando Vargas Romero, Cristina Vanesa Durán Grados
The concentration of traffic-related air pollutants (TRAPs) inside transport microenvironments takes on relevance today in many megacities with high population density, intense traffic, and prolonged travel times. These conditions can intensify exposure to TRAPs and worsen public health problems. TRAP concentrations in these microenvironments are changing because of the introduction of cleaner technologies. In this study, we compare the ultrafine particles measured inside diesel, gas, and electric buses during their normal operation in Bogotá, Colombia. We used a miniature diffusion size classifier (DiSCmini) to measure ultrafine particle concentrations, average particle size, and the lung-deposited surface area. Our results revealed significantly lower levels of this pollutant inside electric buses. The concentration of ultrafine particles per cubic centimeter is about 41% and 27% lower in electric buses compared to diesel and gas, respectively. The lung-deposited surface area is also lower in electric buses. Nevertheless, the average particle size in electric buses is 10% and 18% smaller compared to diesel and gas, respectively.
{"title":"Ultrafine Particles on Electric, Gas, and Diesel Buses in the Mass Transit Buses of Bogotá, Colombia","authors":"Diego Armando Vargas Romero, Cristina Vanesa Durán Grados","doi":"10.1177/03611981231213081","DOIUrl":"https://doi.org/10.1177/03611981231213081","url":null,"abstract":"The concentration of traffic-related air pollutants (TRAPs) inside transport microenvironments takes on relevance today in many megacities with high population density, intense traffic, and prolonged travel times. These conditions can intensify exposure to TRAPs and worsen public health problems. TRAP concentrations in these microenvironments are changing because of the introduction of cleaner technologies. In this study, we compare the ultrafine particles measured inside diesel, gas, and electric buses during their normal operation in Bogotá, Colombia. We used a miniature diffusion size classifier (DiSCmini) to measure ultrafine particle concentrations, average particle size, and the lung-deposited surface area. Our results revealed significantly lower levels of this pollutant inside electric buses. The concentration of ultrafine particles per cubic centimeter is about 41% and 27% lower in electric buses compared to diesel and gas, respectively. The lung-deposited surface area is also lower in electric buses. Nevertheless, the average particle size in electric buses is 10% and 18% smaller compared to diesel and gas, respectively.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139156031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-26DOI: 10.1177/03611981231212194
Ignatius (Po) Lam, Hubert Law, B. Maroney
This paper presents the history and development of criteria for both the design response-spectrum method for ordinary, common bridges analyzed by the modal-superposition method, and the ground-motion time-history analysis method and inputs for designing major, important long-span bridges. This paper addresses various challenges encountered by the designers related to implementation of ground-motion design criteria.
{"title":"Seismic Ground-Motion Design Criteria for Highway Bridges from the Perspective of Design Engineers","authors":"Ignatius (Po) Lam, Hubert Law, B. Maroney","doi":"10.1177/03611981231212194","DOIUrl":"https://doi.org/10.1177/03611981231212194","url":null,"abstract":"This paper presents the history and development of criteria for both the design response-spectrum method for ordinary, common bridges analyzed by the modal-superposition method, and the ground-motion time-history analysis method and inputs for designing major, important long-span bridges. This paper addresses various challenges encountered by the designers related to implementation of ground-motion design criteria.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139156194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-23DOI: 10.1177/03611981231212162
Parth Rana, Fereshteh Sattari, L. Lefsrud, Michael Hendry
Safe railway operation is vital for public safety, the environment, and property. Concurrent with climbing amounts of rail traffic on the Canadian rail network are increases in the last decade in the annual crash counts for derailment, collision, and highway railroad grade crossings (HRGCs). HRGCs are important spatial areas of the rail network, and the development of community areas near railway tracks increases the risk of HRGC crashes between highway vehicles and moving trains, resulting in consequences varying from property damage to injuries and fatalities. This research aims to identify major factors that cause HRGC crashes and affect the severity of associated casualties. Using these causal factors and ensemble algorithms, machine learning models were developed to analyze HRGC crashes and the severity of associated casualties between 2001 and 2022 in Canada. Furthermore, spatial autocorrelation and optimized hotspot analysis tools from ArcGIS software were used to identify hotspot locations of HRGC crashes. The optimized hotspot analysis shows the clustering of HRGC crashes around major Canadian cities. The analysis of cluster characteristics supports the results obtained for causal factors of HRGC crashes. These research outcomes help one to better understand the major causal factors and hotspot locations of HRGC crashes and assist authorities in implementing countermeasures to improve the safety of HRGCs across the rail network.
{"title":"Machine Learning Approach to Enhance Highway Railroad Grade Crossing Safety by Analyzing Crash Data and Identifying Hotspot Crash Locations","authors":"Parth Rana, Fereshteh Sattari, L. Lefsrud, Michael Hendry","doi":"10.1177/03611981231212162","DOIUrl":"https://doi.org/10.1177/03611981231212162","url":null,"abstract":"Safe railway operation is vital for public safety, the environment, and property. Concurrent with climbing amounts of rail traffic on the Canadian rail network are increases in the last decade in the annual crash counts for derailment, collision, and highway railroad grade crossings (HRGCs). HRGCs are important spatial areas of the rail network, and the development of community areas near railway tracks increases the risk of HRGC crashes between highway vehicles and moving trains, resulting in consequences varying from property damage to injuries and fatalities. This research aims to identify major factors that cause HRGC crashes and affect the severity of associated casualties. Using these causal factors and ensemble algorithms, machine learning models were developed to analyze HRGC crashes and the severity of associated casualties between 2001 and 2022 in Canada. Furthermore, spatial autocorrelation and optimized hotspot analysis tools from ArcGIS software were used to identify hotspot locations of HRGC crashes. The optimized hotspot analysis shows the clustering of HRGC crashes around major Canadian cities. The analysis of cluster characteristics supports the results obtained for causal factors of HRGC crashes. These research outcomes help one to better understand the major causal factors and hotspot locations of HRGC crashes and assist authorities in implementing countermeasures to improve the safety of HRGCs across the rail network.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139161167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-22DOI: 10.1177/03611981231211891
Bujing Liu, J. Brian Anderson, James S. Davidson
Departments of transportation are required to inspect and rate bridges that span more than 20 ft (6.1 m). One frequent challenge is rating shallow-buried corrugated metal culverts, since there are no standard methodologies deemed applicable to all sections and depths for defining the resistance when moment or combined moment and thrust controls. The commonly used Culvert ANalysis and DEsign (CANDE) finite element software was developed specifically for culvert design; its companion program, CANDE Tool Box, enables computing of load rating factors. However, owing to nonlinearities associated with soil–structure interaction and yielding of the corrugated cross-section, extracting accurate representations of available resistance for shallow-buried corrugated metal culverts may require a cumbersome iterative procedure. Furthermore, the resulting rating factor from not properly implementing nonlinear procedures may indicate an available resistance that is unconservative from a safety perspective. Recent improvements adopted by AASHTO and incorporated into CANDE include combined thrust–moment criterion, but are deemed suitable only for culverts with deep corrugation cross-sections. The objective of this research was therefore to assess flexure criteria for load rating shallow-buried corrugated metal pipe and arch structures, including standard corrugation cross-sections, to simplify the process without significantly sacrificing accuracy. Challenges with available methods and recently implemented combined criterion for the shallow-buried culvert scenario are first discussed. A modified flexural capacity criterion based on load and resistance factor rating is then developed and presented. Finally, the accuracy and applicability of the methodologies are assessed using a range of practical corrugated metal culvert dimensions and parameters.
{"title":"Flexural Capacity Criteria for Load And Resistance Factor Rating of Shallow Covered Corrugated Metal Culverts","authors":"Bujing Liu, J. Brian Anderson, James S. Davidson","doi":"10.1177/03611981231211891","DOIUrl":"https://doi.org/10.1177/03611981231211891","url":null,"abstract":"Departments of transportation are required to inspect and rate bridges that span more than 20 ft (6.1 m). One frequent challenge is rating shallow-buried corrugated metal culverts, since there are no standard methodologies deemed applicable to all sections and depths for defining the resistance when moment or combined moment and thrust controls. The commonly used Culvert ANalysis and DEsign (CANDE) finite element software was developed specifically for culvert design; its companion program, CANDE Tool Box, enables computing of load rating factors. However, owing to nonlinearities associated with soil–structure interaction and yielding of the corrugated cross-section, extracting accurate representations of available resistance for shallow-buried corrugated metal culverts may require a cumbersome iterative procedure. Furthermore, the resulting rating factor from not properly implementing nonlinear procedures may indicate an available resistance that is unconservative from a safety perspective. Recent improvements adopted by AASHTO and incorporated into CANDE include combined thrust–moment criterion, but are deemed suitable only for culverts with deep corrugation cross-sections. The objective of this research was therefore to assess flexure criteria for load rating shallow-buried corrugated metal pipe and arch structures, including standard corrugation cross-sections, to simplify the process without significantly sacrificing accuracy. Challenges with available methods and recently implemented combined criterion for the shallow-buried culvert scenario are first discussed. A modified flexural capacity criterion based on load and resistance factor rating is then developed and presented. Finally, the accuracy and applicability of the methodologies are assessed using a range of practical corrugated metal culvert dimensions and parameters.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139165750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-18DOI: 10.1177/03611981231208200
Bowen Yang, J. Steelman, Jay A. Puckett, D. Linzell
Platooning may benefit heavy truck transportation through fuel savings, reduced congestion, enhanced safety, and lower emissions. In the future, platoons may be able to act as mobile-WIM stations, and their permit process and allowable load limits may differ from unregulated trucks in a convoy. Previous reliability-based studies have focused on the Strength I limit state and have shown that trucks can operate at weights exceeding standard legal load limits even with short headways at operating-level reliability. However, the Service III limit state often governs prestressed concrete bridges. The AASHTO Manual for Bridge Evaluation does not specify a target reliability index (β) nor reliability-based evaluation guidance for the Service III limit state. The work presented here performed reliability analyses to investigate implicit reliability indices (βImplicit) inferred from bridges designed according to current and past AASHTO criteria, as well as cracking probabilities. Design live loads were used to evaluate the Service III limit state for prestressed concrete NU I-girder bridges, optimally designed using LRFD and LFD/allowable stress design (ASD). Various span lengths, numbers, continuity conditions, prestress loss methods, and allowable tension stress levels were considered. Cracking probabilities ranged between 10% and 67%, which indicates that optimally designed bridges may crack during their service life. Although beyond the scope of the study, the present work suggests a reexamination of service behavior and performance is appropriate, using an alternate mechanistic approach to estimate potential cyclic damage and aid life-cycle assessment. Such assessments could provide a more rational framework for platoon operations while maintaining bridge health and safety.
通过节省燃料、减少拥堵、加强安全和降低排放，排队可能会使重型卡车运输受益。未来，排载可能会成为移动 WIM 站，其许可程序和允许的负载限制可能会与车队中未受管制的卡车不同。以往基于可靠性的研究主要集中在强度 I 极限状态，结果表明，即使在运营级可靠性下，卡车也能以超过标准法定载荷限制的重量运行，甚至在短距离间隔内也是如此。然而，预应力混凝土桥梁通常采用服务 III 极限状态。AASHTO 的《桥梁评估手册》既没有规定目标可靠性指数 (β)，也没有为 Service III 极限状态提供基于可靠性的评估指导。本文介绍的工作进行了可靠性分析，以研究根据当前和过去的 AASHTO 标准设计的桥梁推断出的隐含可靠性指数 (βImplicit)，以及开裂概率。采用 LRFD 和 LFD/容许应力设计 (ASD) 优化设计的预应力混凝土 NU I 梁桥，其设计活荷载用于评估服务 III 极限状态。考虑了各种跨度、数量、连续性条件、预应力损失方法和允许拉应力水平。开裂概率在 10% 到 67% 之间，这表明经过优化设计的桥梁在使用寿命期间可能会开裂。尽管超出了本研究的范围，但本研究表明，重新审查使用行为和性能是适当的，可以使用另一种机械方法来估算潜在的周期性损坏并帮助进行生命周期评估。此类评估可为排险作业提供更合理的框架，同时维护桥梁的健康和安全。
{"title":"Reliability-Based Service III Evaluation for Prestressed Girder Bridges Under Platoon Loads","authors":"Bowen Yang, J. Steelman, Jay A. Puckett, D. Linzell","doi":"10.1177/03611981231208200","DOIUrl":"https://doi.org/10.1177/03611981231208200","url":null,"abstract":"Platooning may benefit heavy truck transportation through fuel savings, reduced congestion, enhanced safety, and lower emissions. In the future, platoons may be able to act as mobile-WIM stations, and their permit process and allowable load limits may differ from unregulated trucks in a convoy. Previous reliability-based studies have focused on the Strength I limit state and have shown that trucks can operate at weights exceeding standard legal load limits even with short headways at operating-level reliability. However, the Service III limit state often governs prestressed concrete bridges. The AASHTO Manual for Bridge Evaluation does not specify a target reliability index (β) nor reliability-based evaluation guidance for the Service III limit state. The work presented here performed reliability analyses to investigate implicit reliability indices (βImplicit) inferred from bridges designed according to current and past AASHTO criteria, as well as cracking probabilities. Design live loads were used to evaluate the Service III limit state for prestressed concrete NU I-girder bridges, optimally designed using LRFD and LFD/allowable stress design (ASD). Various span lengths, numbers, continuity conditions, prestress loss methods, and allowable tension stress levels were considered. Cracking probabilities ranged between 10% and 67%, which indicates that optimally designed bridges may crack during their service life. Although beyond the scope of the study, the present work suggests a reexamination of service behavior and performance is appropriate, using an alternate mechanistic approach to estimate potential cyclic damage and aid life-cycle assessment. Such assessments could provide a more rational framework for platoon operations while maintaining bridge health and safety.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139175887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-18DOI: 10.1177/03611981231214522
Wenming Shi, Fuyong Yang, Xuehao Feng, Yiyang Liu, M. Jin
Carbon dioxide (CO2) emissions reduction has become an ever-growing concern in China and the government has proposed the goals of carbon peak and carbon neutrality. To better address this concern, this work pays particular attention to high-speed railway (HSR) operations and examines their spatiotemporal effects and potential mechanism on CO2 emissions. Using a geographically and temporally weighted regression (GTWR) model to fit a balanced panel dataset from the period 2008 to 2018, we have the following main findings. First, the GTWR model performs better than the pooled panel regression model as it considers temporal and spatial variations in factors of CO2 emissions simultaneously. Second, the temporally varying coefficients of HSR operations indicate their consistent contributions to emissions reduction, suggesting that the national development of HSRs can provide significant emissions reduction benefits. Third, as revealed by the spatially varying coefficients of HSR operations, most provinces can mitigate CO2 emissions by promoting HSRs, particularly in Shanxi, Hebei, and Shaanxi, owing to the larger contributions of HSR operations to CO2 emissions reduction. Finally, the contributions of HSR operations to emissions reduction can be transmitted through the mechanism of technological progress. These findings can offer valuable insights into cross-collaborative and province-specific policymaking for mitigating CO2 emissions.
{"title":"Spatiotemporal Heterogeneity of Carbon Dioxide Emissions: Evidence from High-Speed Railway Operations in China","authors":"Wenming Shi, Fuyong Yang, Xuehao Feng, Yiyang Liu, M. Jin","doi":"10.1177/03611981231214522","DOIUrl":"https://doi.org/10.1177/03611981231214522","url":null,"abstract":"Carbon dioxide (CO2) emissions reduction has become an ever-growing concern in China and the government has proposed the goals of carbon peak and carbon neutrality. To better address this concern, this work pays particular attention to high-speed railway (HSR) operations and examines their spatiotemporal effects and potential mechanism on CO2 emissions. Using a geographically and temporally weighted regression (GTWR) model to fit a balanced panel dataset from the period 2008 to 2018, we have the following main findings. First, the GTWR model performs better than the pooled panel regression model as it considers temporal and spatial variations in factors of CO2 emissions simultaneously. Second, the temporally varying coefficients of HSR operations indicate their consistent contributions to emissions reduction, suggesting that the national development of HSRs can provide significant emissions reduction benefits. Third, as revealed by the spatially varying coefficients of HSR operations, most provinces can mitigate CO2 emissions by promoting HSRs, particularly in Shanxi, Hebei, and Shaanxi, owing to the larger contributions of HSR operations to CO2 emissions reduction. Finally, the contributions of HSR operations to emissions reduction can be transmitted through the mechanism of technological progress. These findings can offer valuable insights into cross-collaborative and province-specific policymaking for mitigating CO2 emissions.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139174783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-18DOI: 10.1177/03611981231211527
Yun Xiao, Guangmin Wang, Meng Xu
A bi-level programming model is formulated to determine a government subsidy scheme for shared parking management. The government, as the upper-level decision-maker, seeks to maximize the social benefit by providing subsidy to the shared parking platform, incentivizing the platform to rent more shared parking slots, which can increase the utilization rate of idle parking slots and reduce the curbside parking cruising time of parking demanders. At the lower-level formulation, the shared parking platform, as a reseller, not only matches shared parking slot demanders but also determines which shared parking slots to rent, which is approached by a two-sided decision-making process. A “one-to-many” matching principle is adopted for the platform to maximize its revenue. A modified genetic algorithm is designed to solve the proposed model. Results indicate that the government subsidy has a positive impact on stimulating the shared parking market. Specifically, from the perspective of the government, the subsidy can increase the number of matched shared parking demanders, improve the supply of parking slots, and reduce curbside parking cruising time. From the perspective of the shared parking platform, the subsidy can lead to higher revenue.
{"title":"Determining an Optimal Government Subsidy Scheme for Shared Parking Management via a Bi-Level Programming Approach","authors":"Yun Xiao, Guangmin Wang, Meng Xu","doi":"10.1177/03611981231211527","DOIUrl":"https://doi.org/10.1177/03611981231211527","url":null,"abstract":"A bi-level programming model is formulated to determine a government subsidy scheme for shared parking management. The government, as the upper-level decision-maker, seeks to maximize the social benefit by providing subsidy to the shared parking platform, incentivizing the platform to rent more shared parking slots, which can increase the utilization rate of idle parking slots and reduce the curbside parking cruising time of parking demanders. At the lower-level formulation, the shared parking platform, as a reseller, not only matches shared parking slot demanders but also determines which shared parking slots to rent, which is approached by a two-sided decision-making process. A “one-to-many” matching principle is adopted for the platform to maximize its revenue. A modified genetic algorithm is designed to solve the proposed model. Results indicate that the government subsidy has a positive impact on stimulating the shared parking market. Specifically, from the perspective of the government, the subsidy can increase the number of matched shared parking demanders, improve the supply of parking slots, and reduce curbside parking cruising time. From the perspective of the shared parking platform, the subsidy can lead to higher revenue.","PeriodicalId":309251,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139173567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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