Transportmetrica最新文献

{"title":"Optimal vehicle capacity and dispatching policy considering crowding in public bus transit services","authors":"Reza Mahmoudi, Saeid Saidi, S. C. Wirasinghe","doi":"10.1080/23249935.2023.2258996","DOIUrl":"https://doi.org/10.1080/23249935.2023.2258996","url":null,"abstract":"AbstractThis study investigates the often overlooked impact of on-board crowding on operational and user costs in public transit systems, specifically within a many-to-many bus transit line with varying demand patterns. While previous research has used mathematical programming for similar problems, this paper employs analytical approaches to offer deeper insights and address fundamental questions. First, we propose an approach to determine optimal bus capacities, factoring in in-vehicle crowding costs, assuming a fixed headway. Second, we explore the optimal dispatching policy for buses with fixed capacities, considering crowding costs. Third, we optimize both headway and vehicle capacity simultaneously. Our findings reveal that optimal vehicle capacity correlates with average passenger trip length and the square root of crowding-discomfort costs, especially when crowding increases linearly with load factor. When both headway and capacity are variable, smaller vehicles with shorter headways are favored, particularly in moderate-demand scenarios, especially with cost-effective staff models like autonomous fleets.KEYWORDS: Bus transit network designcrowdingoptimal dispatching policycontinuum approximation approachmany to many demandtime varying demand Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was financially supported partly by Alberta Innovates and the Natural Sciences and Engineering Research Council of Canada (NSERC). We thank the Department of Civil Engineering and Schulich School of Engineering at the University of Calgary.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"2015 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136235685","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}

{"title":"A toll-based approach for regulating hazmat transportation network considering boundedly rational route choice","authors":"Honggang Zhang, Wei Wang, Zhiyuan Liu","doi":"10.1080/23249935.2023.2259010","DOIUrl":"https://doi.org/10.1080/23249935.2023.2259010","url":null,"abstract":"AbstractThis paper introduces a novel toll charge to regulate transportation of hazardous materials (hazmat), taking into account that carriers are bounded rational decision-makers. In the case of bounded rationality, the route choice behaviour of carriers is described based on the link-based perception error model. Then, a novel bi-level programming model is developed, which aims to minimise both total tolls and maximum total risk, while finding the shortest path according to certain perception errors. To effectively solve the proposed model, it is decomposed into two subproblems, and the particle swarm optimisation algorithm and K-shortest paths algorithm are designed. Furthermore, an extended model is developed to ensure risk equity between different links, where the constraints on maximum link risk are added. Numerical experiments are conducted to validate the proposed models and algorithms, demonstrating that maximum total risk can be effectively mitigated and risk equity between different links can be achieved.KEYWORDS: Hazmat transportationtoll settingbounded rationalityrisk equitybi-level programming AcknowledgementThe authors are grateful to the anonymous referees for their constructive comments and suggestions.Disclosure statementNo potential conflict of interest was reported by the author(s).Author contributionsAll authors contributed to the study's conception and design. Material preparation and analysis were performed by Honggang Zhang, Wei Wang, and Zhiyuan Liu. The first draft of the manuscript was written by Honggang Zhang and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.Additional informationFundingThis study is supported by the Key Project (grant no. 52131203) and the Youth Program (grant no. 52102375) of the National Natural Science Foundation of China, the Youth Program (grant no. BK20210247) of the Natural Science Foundation of Jiangsu Province in China, the Start-up Research Fund of Southeast University (grant no. RF1028623057), and the High-Level Personnel Project of Jiangsu Province in China.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"242 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135396543","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}

{"title":"A multiclass simulation-based dynamic traffic assignment model for mixed traffic flow of connected and autonomous vehicles and human-driven vehicles","authors":"Behzad Bamdad Mehrabani, Jakob Erdmann, Luca Sgambi, Seyedehsan Seyedabrishami, Maaike Snelder","doi":"10.1080/23249935.2023.2257805","DOIUrl":"https://doi.org/10.1080/23249935.2023.2257805","url":null,"abstract":"AbstractConnected and Autonomous Vehicles (CAVs) may exhibit different driving and route choice behaviours compared to Human-Driven Vehicles (HDVs), which can result in a mixed traffic flow with multiple classes of route choice behaviour. Therefore, it is necessary to solve the Multiclass Traffic Assignment Problem (TAP) for mixed traffic flow. However, most existing studies have relied on analytical solutions. Furthermore, simulation-based methods have not fully considered all of CAVs’ potential capabilities. This study presents an open-source solution framework for the multiclass simulation-based TAP in mixed traffic of CAVs and HDVs. The proposed model assumes that CAVs follow system optimal with rerouting capabilities, while HDVs follow user equilibrium. It also considers the impact of CAVs on road capacity at both micro and meso scales. The proposed model is demonstrated through three case studies. This study provides a valuable tool that can consider several assumptions for better understanding the impact of CAVs on mixed traffic flow.KEYWORDS: Simulation-based traffic assignmentConnected and Autonomous Vehicles (CAVs)mixed traffic flowHuman Driven Vehicles (HDVs)multiclass traffic assignment Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThe corresponding author was supported by the Université catholique de Louvain under the ‘Fonds Speciaux de Recherche’ and the ‘Erasmus +’ programmes.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134910622","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}

{"title":"Safe and efficient manoeuvring for emergency vehicles in autonomous traffic using multi-agent proximal policy optimisation","authors":"Leandro Parada, Eduardo Candela, Luis Marques, Panagiotis Angeloudis","doi":"10.1080/23249935.2023.2246586","DOIUrl":"https://doi.org/10.1080/23249935.2023.2246586","url":null,"abstract":"Manoeuvring in the presence of emergency vehicles is still a major issue for vehicle autonomy systems. Most studies that address this topic are based on rule-based methods, which cannot cover all possible scenarios that can take place in autonomous traffic. Multi-Agent Proximal Policy Optimisation (MAPPO) has recently emerged as a powerful method for autonomous systems because it allows for training in thousands of different situations. In this study, we present an approach based on MAPPO to guarantee the safe and efficient manoeuvring of autonomous vehicles in the presence of an emergency vehicle. We introduce a risk metric that summarises the potential risk of collision in a single index. The proposed method generates cooperative policies allowing the emergency vehicle to go at 15% higher average speed while maintaining high safety distances. Moreover, we conduct a comprehensive evaluation of our method in a wide range of scenarios, including assessing the trade-offs between traffic efficiency and safety, measuring the scalability of the approach with respect to the number of autonomous vehicles, analysing different distributions of mixed human and autonomous traffic, and examining the various levels of cooperation and competition among agents.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136392616","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}

{"title":"Exploring the spatiotemporal correlation among traffic crashes on arterials with signal coordination","authors":"Yingfei Fan, Runhua Guo, Xinguo Jiang, Mengqing Xu, Guopeng Zhang, Xiang Li, Shiwei Xu, Qi Liang","doi":"10.1080/23249935.2020.1860154","DOIUrl":"https://doi.org/10.1080/23249935.2020.1860154","url":null,"abstract":"","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"1 1","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2020-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249935.2020.1860154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45594883","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}

{"title":"The stochastic multi-modal hub location problem with direct link strategy and multiple capacity levels for cargo delivery systems","authors":"Xiaoting Shang, Kai Yang, B. Jia, Ziyou Gao","doi":"10.1080/23249935.2020.1776787","DOIUrl":"https://doi.org/10.1080/23249935.2020.1776787","url":null,"abstract":"This paper introduces the stochastic multi-modal hub location problem with direct link strategy and multiple capacity levels for cargo delivery systems under demand uncertainty. For capturing the u...","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"1 1","pages":"1-31"},"PeriodicalIF":0.0,"publicationDate":"2020-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249935.2020.1776787","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42463822","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}

{"title":"Service quality effects on air passenger intentions: a service chain perspective","authors":"Yu-Chiun Chiou, Yen-Heng Chen","doi":"10.1080/18128602.2010.548837","DOIUrl":"https://doi.org/10.1080/18128602.2010.548837","url":null,"abstract":"This study divides entire airline services into eight service stages and uses a second-order confirmatory factor analysis (CFA) to constitute service quality and to examine the causal relationships between two consecutive service stages from a service chain perspective. Two conceptual frameworks – overall framework and service chain framework are proposed. The former incorporates the constructs of service quality, sacrifice, servicescape, service value, satisfaction, switching barriers, and behavioural intentions combined with seven hypothetical causal relationships. The latter depicts seven hypothetical causal relationships between two consecutive service stages. The proposed models are validated by a case study of Spring Airlines, a low-cost carrier (LCC) based in China. The empirical results support all hypotheses except hypothesis 7 that service quality positively impacts behavioural intentions. Notably, test results for the interrelationships between two consecutive service stages suggest that a lack of satisfaction at a specific service stage will affect customer perception of the consequent service stage. Therefore, to improve the service quality for a service stage, the service quality of all upstream service stages must be improved first. This study also found that service quality has a large effect although not direct on behavioural intentions while sacrifice has the smallest effect. A low-fare strategy may not be effective when an airline fails to deliver high-quality service.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"8 1","pages":"406 - 426"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/18128602.2010.548837","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59925806","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}

{"title":"The impact of traffic images on travel time valuation in stated-preference choice experiments","authors":"L. Rizzi, Juan Pablo Limonado, S. Steimetz","doi":"10.1080/18128602.2010.551524","DOIUrl":"https://doi.org/10.1080/18128602.2010.551524","url":null,"abstract":"We develop a simple but modern stated-preference (SP) choice experiment to analyse the impact of traffic images on the estimated value of travel time savings (VTTS). A random subsample of survey respondents view computer-generated images that depict traffic conditions for congested and free-flow portions of hypothetical travel alternatives. The remaining respondents receive otherwise-identical surveys that only verbally describe the attributes of those alternatives. From surveys with images, the estimated VTTS is $7.40 per hour for congested travel time and $5.70 for free-flow travel time, implying a ‘congestion premium’ of 30%. From surveys without images, however, congested and free-flow VTTS estimates are identical at $5.90 per hour. Our results indicate that traffic images, however rudimentary, can substantially influence travel-time valuation, thus compelling further research on incorporating them into SP experimental design.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"8 1","pages":"427 - 442"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/18128602.2010.551524","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59925816","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}

{"title":"Three new models for the flow–density relationship: derivation and testing for freeway and urban data","authors":"J. M. del Castillo","doi":"10.1080/18128602.2011.556680","DOIUrl":"https://doi.org/10.1080/18128602.2011.556680","url":null,"abstract":"Three new models for the flow–density relationship are proposed in this work. The resulting flow–density curves are concave in the whole range of feasible values for the parameters. These models have four parameters, three of them being the jam density, the free-flow speed and the kinematic wave speed. The fourth parameter is a shape parameter. The models allow for a great flexibility for fitting of real traffic flow and density data. A remarkable property of these models is the fact that they yield a bilinear fundamental diagram when the shape parameter tends to infinity. The models have been tested with freeway data and urban data. The results demonstrate that the models achieve an excellent goodness of fit and yield realistic estimates of the parameters. The models proposed in this work are a valuable tool not only for fitting flow–density data but also for its use in traffic flow dynamic models.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"8 1","pages":"443 - 465"},"PeriodicalIF":0.0,"publicationDate":"2012-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/18128602.2011.556680","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59925929","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}

{"title":"An ant colony system-based hybrid algorithm for an emergency roadway repair time-space network flow problem","authors":"S. Yan, Y. Shih","doi":"10.1080/18128602.2010.515550","DOIUrl":"https://doi.org/10.1080/18128602.2010.515550","url":null,"abstract":"In this study, we employ an ant colony system (ACS) algorithm, coupled with a threshold accepting technique, to develop an ACS-based hybrid algorithm that is capable of efficiently solving an emergency roadway repair time-space network flow problem. To test how well the algorithm may be applied to actual operations, we perform a case study using data from the 1999 Chi-Chi earthquake in Taiwan. To assess the robustness of the model and solution algorithm for different roadway network patterns, we generate 16 problem instances with four different roadway network patterns. The method that uses CPLEX to directly solve the problem and a previously proposed heuristic are used to compare with our algorithm. The test results show that our algorithm is both effective and efficient enough to solve problems with different roadway networks, and therefore, would be useful in practice.","PeriodicalId":49416,"journal":{"name":"Transportmetrica","volume":"8 1","pages":"361 - 386"},"PeriodicalIF":0.0,"publicationDate":"2012-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/18128602.2010.515550","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"59925607","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}