Transportation Science eJournal最新文献_第2页

A Deterministic Model for the Transshipment Problem of a Fast Fashion Retailer under Capacity Constraints 产能约束下快时尚零售商转运问题的确定性模型

Transportation Science eJournal Pub Date : 2019-11-28 DOI: 10.2139/ssrn.3512800

S. Naderi, K. Kilic, A. Dasci

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引用次数: 20

A Heuristic for Learn-and-Optimize New Mobility Services with Equity and Efficiency Metrics 具有公平和效率度量的新移动服务学习和优化的启发式方法

Transportation Science eJournal Pub Date : 2019-11-16 DOI: 10.2139/ssrn.3488466

Fangzhou Yu, Qi Luo, T. Fabusuyi, R. Hampshire

{"title":"A Heuristic for Learn-and-Optimize New Mobility Services with Equity and Efficiency Metrics","authors":"Fangzhou Yu, Qi Luo, T. Fabusuyi, R. Hampshire","doi":"10.2139/ssrn.3488466","DOIUrl":"https://doi.org/10.2139/ssrn.3488466","url":null,"abstract":"We are motivated by a common dilemma that exists when coupling new mobility services with existing transportation systems — the unbalanced nature of operations with regard to efficiency and equity objectives. To address this issue, we study the joint routing and resource allocation problem. Vehicles need to repeatedly and simultaneously choose the route and the resource (i.e., capacity) allocation policy with unknown demand. Efficiency is measured by the total travel distance, and equity is measured by the minimum service level. We propose a two-phase heuristic that solve the learn-and-optimize problem iteratively with small cumulative regret. In Phase 1, the algorithm selects the best demand estimator; In Phase 2, it finds the near optimal operational plan. We examine the effectiveness of the algorithm in a case study from the Miami Dade County that uses idle shuttle vehicles to deliver packages during off-peak hours. The results show that we can improve the minimum service level from 33% to approximately 68% while maintaining small incremental travel costs. This heuristic can provide a general guidance for practitioners and researchers on operating new mobility services in a stochastic network.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130020638","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}

引用次数: 0

Faster Deliveries and Smarter Order Assignments for an On-Demand Meal Delivery Platform 为按需送餐平台提供更快的配送和更智能的订单分配

Transportation Science eJournal Pub Date : 2019-10-12 DOI: 10.2139/ssrn.3469015

W. Mao, Liu Ming, Ying Rong, Christopher S. Tang, Huan Zheng

{"title":"Faster Deliveries and Smarter Order Assignments for an On-Demand Meal Delivery Platform","authors":"W. Mao, Liu Ming, Ying Rong, Christopher S. Tang, Huan Zheng","doi":"10.2139/ssrn.3469015","DOIUrl":"https://doi.org/10.2139/ssrn.3469015","url":null,"abstract":"Academic/Practical Relevance: Our intent is to identify the underlying factors and develop an order assignment policy that can help an on-demand meal delivery service platform to grow. \u0000 \u0000Methodology: By analyzing transactional data obtained from an online meal delivery platform in Hangzhou (China) over a two-month period in 2015, we examine the impact of meal delivery performance on a customer's future orders. Through a simulation study, we illustrate the importance of incorporating our empirical results into the development of a smarter \"order assignment policy\". \u0000 \u0000Results: We find empirical evidence that an \"early delivery'' is positively correlated with customer retention: a 10-minute earlier delivery is associated with an increase of one order per month from each customer. However, we find that the negative effect on future orders associated with \"late deliveries'' is much stronger than the positive effect associated with \"early deliveries\". Moreover, we show empirically that a driver's individual local area knowledge and prior delivery experience can reduce late deliveries significantly. Finally, through a simulation study, we illustrate how one can incorporate our empirical results in the development of an order assignment policy that can help a platform to grow its business through customer retention. \u0000 \u0000Managerial Implications: Our empirical results and our simulation study suggest that to increase future customer orders, an on-demand service platform should address the issues arising from both the supply side (i.e., driver's local area knowledge and delivery experience) and the demand side (i.e., asymmetric impacts of early and late deliveries on future customer orders) into their operations.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"165 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116131366","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}

引用次数: 17

Monge Properties, Optimal Greedy Policies, and Policy Improvement for the Dynamic Stochastic Transportation Problem 动态随机运输问题的Monge性质、最优贪婪策略及策略改进

Transportation Science eJournal Pub Date : 2019-09-06 DOI: 10.2139/ssrn.3067130

Alexander S. Estes, M. Ball

引用次数: 1

Heuristics Designed For the Traveling Salesman Problem 旅行推销员问题的启发式设计

Transportation Science eJournal Pub Date : 2019-05-03 DOI: 10.2139/ssrn.3497478

Shaik Mastan, U. Balakrishnan, G. Sankar Sekhar Raju

引用次数: 2

Disproving the User Toll Theory 反驳用户收费理论

Transportation Science eJournal Pub Date : 2018-02-04 DOI: 10.2139/ssrn.3117992

Hak Choi

引用次数: 0

Lupton's Negative Toll Theory 卢普顿负收费理论

Transportation Science eJournal Pub Date : 2018-01-23 DOI: 10.2139/ssrn.3107680

Hak Choi

引用次数: 1

Planning of Truck Platoons: A Literature Review and Directions for Future Research 卡车排规划:文献综述及未来研究方向

Transportation Science eJournal Pub Date : 2017-06-17 DOI: 10.2139/ssrn.2988195

Anirudh Kishore Bhoopalam, Niels A. H. Agatz, R. Zuidwijk

引用次数: 205

An Empirical Analysis of Risk Factors in Aviation: Evidence from 1995-2016 NTSB Data 航空风险因素的实证分析——来自1995-2016年NTSB数据的证据

Transportation Science eJournal Pub Date : 2016-12-19 DOI: 10.2139/ssrn.2887620

R. Herman, Rossitza B. Wooster

引用次数: 0

Dynamic Type Matching 动态类型匹配

Transportation Science eJournal Pub Date : 2016-06-22 DOI: 10.2139/ssrn.2592622

Ming Hu, Yun Zhou

{"title":"Dynamic Type Matching","authors":"Ming Hu, Yun Zhou","doi":"10.2139/ssrn.2592622","DOIUrl":"https://doi.org/10.2139/ssrn.2592622","url":null,"abstract":"Problem definition: We consider an intermediary’s problem of dynamically matching demand and supply of heterogeneous types in a periodic-review fashion. Specifically, there are two disjoint sets of demand and supply types, and a reward for each possible matching of a demand type and a supply type. In each period, demand and supply of various types arrive in random quantities. The platform decides on the optimal matching policy to maximize the expected total discounted rewards, given that unmatched demand and supply may incur waiting or holding costs, and will be fully or partially carried over to the next period. Academic/practical relevance: The problem is crucial to many intermediaries who manage matchings centrally in a sharing economy. Methodology: We formulate the problem as a dynamic program. We explore the structural properties of the optimal policy and propose heuristic policies. Results: We provide sufficient conditions on matching rewards such that the optimal matching policy follows a priority hierarchy among possible matching pairs. We show that those conditions are satisfied by vertically and unidirectionally horizontally differentiated types, for which quality and distance determine priority, respectively. Managerial implications: The priority property simplifies the matching decision within a period, and the trade-off reduces to a choice between matching in the current period and that in the future. Then the optimal matching policy has a match-down-to structure when considering a specific pair of demand and supply types in the priority hierarchy.","PeriodicalId":432405,"journal":{"name":"Transportation Science eJournal","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124820326","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}

引用次数: 98