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model for Corrective Maintenance Scheduling of Rail Transit Networks: Application to Athens Metro

JOURNAL OF INFRASTRUCTURE SYSTEMS 2019年第1期25卷 4018035.1-4018035.11页

作者： Argyropoulou, Konstantina Iliopoulou, Christina Kepaptsoglou, Konstantinos Natl Tech Univ Athens Sch Rural & Surveying Engn Iroon Polytechniou St Grad Student Athens 15770 Greece Natl Tech Univ Athens Sch Rural & Surveying Engn Iroon Polytechniou St Athens 15770 Greece Natl Tech Univ Athens Sch Rural & Surveying Engn Iroon Polytechniou St Athens 15770 Greece Natl Tech Univ Athens Sch Rural & Surveying Engn 5 Iroon Polytech St Athens 15770 Greece

Efficient and safe rail transit (metro) operations require regularly inspected and properly maintained infrastructures. While preventive maintenance is usually undertaken following a predetermined schedule, decisions on repairs and corrective maintenance are usually scheduled ad hoc, following inspections. This paper presents a model for optimally scheduling corrective maintenance activities in a rail transit network, following their identification as part of an inspection process. An integer programming model is formulated for that purpose, aiming at minimizing passenger delay caused by reduced operational speeds on degraded rail segments and prioritizing activities in segments with intensive operations;higher train traffic and associated train loads;and under budget, staff, and other practical constraints. The model is applied for the case of the Athens, Greece, metro system and results are discussed.

关键词： Metro system Maintenance scheduling Corrective maintenance integer programming model

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"Almost-stable" matchings in the Hospitals/Residents problem with Couples

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CONSTRAINTS 2017年第1期22卷 50-72页

作者： Manlove, David F. McBride, Iain Trimble, James Univ Glasgow Sch Comp Sci Sir Alwyn Williams Bldg Glasgow G12 8QQ Lanark Scotland

The Hospitals / Residents problem with Couples (hrc) models the allocation of intending junior doctors to hospitals where couples are allowed to submit joint preference lists over pairs of (typically geographically close) hospitals. It is known that a stable matching need not exist, so we consider min bp hrc, the problem of finding a matching that admits the minimum number of blocking pairs (i.e., is "as stable as possible"). We show that this problem is NP-hard and difficult to approximate even in the highly restricted case that each couple finds only one hospital pair acceptable. However if we further assume that the preference list of each single resident and hospital is of length at most 2, we give a polynomial-time algorithm for this case. We then present the first integer programming (IP) and Constraint programming (CP) models for min bp hrc. Finally, we discuss an empirical evaluation of these models applied to randomly-generated instances of min bp hrc. We find that on average, the CP model is about 1.15 times faster than the IP model, and when presolving is applied to the CP model, it is on average 8.14 times faster. We further observe that the number of blocking pairs admitted by a solution is very small, i.e., usually at most 1, and never more than 2, for the (28,000) instances considered.

关键词： Most-stable matching Blocking pair Polynomial-time algorithm NP-hardness integer programming model Constraint programming model Empirical evaluation

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"Almost-stable" matchings in the Hospitals/Residents problem with Couples 22nd

"Almost-stable" matchings in the Hospitals/Residents problem...

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22nd International Conference on the Principles and Practice of Constraint programming (CP)

作者： Manlove, David F. McBride, Iain Trimble, James Univ Glasgow Sch Comp Sci Sir Alwyn Williams Bldg Glasgow G12 8QQ Lanark Scotland

ISBN: (纸本)9783319449524

关键词： Most-stable matching Blocking pair Polynomial-time algorithm NP-hardness integer programming model Constraint programming model Empirical evaluation

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A two-echelon capacitated vehicle routing problem with customer classes

A two-echelon capacitated vehicle routing problem with custo...

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作者： Laurens van den Heuvel Vrije University Amsterdam

学位级别：硕士

As an interesting possibility to deal with the introduction of emission zones in city centres, this papers develops a model which uses a transhipment facility outside of the emission zone. Customers are divided in two classes, based on the presence of an hypothesised emission constraint. Emission constrained customers can only be supplied by the emission friendly trucks located at the transhipment facility, whereas the other class of customers can be supplied by both the depot and the transhipment facility. Subsequently, the model aims to minimize the total transportation distance. Both a mathematical and a integer programming model are presented which account for a fleet of homogeneous, capacitated vehicles. By means of minimizing total transportation distance the model aims to solve the two-echelon vehicle routing problem. Proof of work for the model is delivered by means of results for several datasets. To give an impression of the effect of customer classes and two-echelons, a side-by-side comparison with a one-echelon CVRP model is made. Results of the model indicate that the one-echelon CVRP has lower optimal distances than the 2E-CVRP of this paper. Based on this conclusion it could be preferable to solely have emission friendly trucks assuming similar costs. The limited sample size due to the amount of calculations required for solving more datasets prevents the formulation of hard claims about the performance. The insights obtained and the model provided in this paper allow for future contributions, such as including range constraints or including more facilities in the model, to account for a more realistic distribution network. In turn this delivers real-world value with regard to the investment decision of buying only emission friendly vehicles or setting up a distribution network with intermediate facility.

关键词： Multi depot capacitated vehicle routing problem two-echelon vehicle routing problem AMPL integer programming model

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Railway Timetable Rescheduling Based on Priority and Train Order Entropy

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JOURNAL OF COMPUTING IN CIVIL ENGINEERING 2016年第5期30卷 1-8页

作者： Huo, Jianwei Wu, Jianjun Kang, Liujiang Wang, Bo Beijing Jiaotong Univ State Key Lab Rail Traff Control & Safety Beijing 100044 Peoples R China Tianjin Railway Tech & Vocat Coll Dept Urban Rail Tianjin 300240 Peoples R China Beijing Jiaotong Univ Sch Traff & Transportat Beijing 100044 Peoples R China Beijing Municipal Commiss Transport Beijing 100073 Peoples R China

How to reschedule the railway timetable is an important problem in real train operations and management. The main purpose of dispatchers is to minimize the total delay time in the network, which is the sum of time difference between the original timetable and the rescheduling one. This difference is called the disorder. In the railway network, the disorder of trains caused by the timetable rescheduling can be expressed by train order entropy. In this paper, a binary mixed-integer programming model is proposed to reschedule the timetable in the emergent incidents based on priority and train order entropy. In addition, a heuristic algorithm based on the depth-first search method is designed to solve the proposed programming starting at the root and exploring as far as possible along each branch before backtracking. Finally, the total delay time and the train order entropy for the reschedule scheme are discussed. Different emergency incidents are analyzed showing that the duration time of the incident will have a great influence on delay time and train order entropy. (C) 2016 American Society of Civil Engineers.

关键词： Railway rescheduling Delay time Order entropy integer programming model

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The model of Toll Station Planing

The Model of Toll Station Planing

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2017 2nd International Conference on Control, Automation and Artificial Intelligence(CAAI2017)

作者： Dongdong Zhu Furui Dong Wenyang Shi Shuang Zheng Shandong University of Science and Technology

When designing barrier tolls, the shape, size and merging pattern need to be taken into consideration. Besides, the safety codes and standard of accident prevention and throughout capacity must be met while the development and operating costs should be kept as low as possible. Six major factors impacting the toll plaza performance were discussed, including the corresponding relationship between the amount of main lanes in single direction and tollbooth, the critical length of toll plaza meeting safety codes and standards, the critical width of toll plaza, the critical size of transition region, the development cost of toll plaza and its throughput capacity. We set up a multiple index analysis system after calculating those six factors to analyze the pros and cons of the existing toll plaza, which could provide scientific basis for the new design. Moreover, difference motivated principle was applied to determine the weight vector, to comprehensively evaluate the impact of each parameter. To determine the optimal design, we designed and compared three control schemes. The evaluation system was applied to compare the pros and cons of each scheme based on the actual situations, and the optimal scheme was designed through combining the strengths of all three. By investigating the adjustment strategy and corresponding performance of the toll plaza of the different scheme in the case of light and heavy traffic flow, the case when the proportion of automatic driving vehicles increases, and the case under different charging modes, the feasibility and rationality of the optimal scheme was tested. In the process of inspection, we used the queuing theory model to determine the maximum capacity of the toll plaza under the manual toll mode, and used the integer programming model to solve the optimal proportional relation of the three tolling models.

关键词： multi-index comprehensive analysis system difference driving principle queuing theory model integer programming model weight vector

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A slot reallocation model for containership schedule adjustment

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MARITIME POLICY & MANAGEMENT 2016年第1期43卷 136-157页

作者： Lu, Hua-An Mu, Wen-Hung Natl Taiwan Ocean Univ Dept Shipping & Transportat Management Keelung Taiwan

Ship slot capacity is the main sale resource of container shipping lines. However, shipping lines often encounter situations, such as serious ship delays, that require adjustments of shipping schedules, causing the original delivery plans of some consignments to be altered. This study proposes an integer programming model for slot reallocation planning, based on a given adjusted schedule. Decisions regarding empty container repositioning are also examined. This model aims to maximise a company's benefits from deliveries of consignments and movements of empty containers. Available slots are subject to port rotation changes, allowable port handlings and ship capacity. A case study of a deep ocean loop demonstrates optimal slot reallocation, and empty container repositioning is used for illustrative purposes. The reallocation characteristics due to benefit items and the model's applicability to large-scale examples are discussed.

关键词： slot reallocation integer programming model empty container repositioning deep ocean loop

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Assessing the viability of enabling a round-trip carsharing system to accept one-way trips: Application to Logan Airport in Boston

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TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES 2015年 56卷 359-372页

作者： Jorge, Diana Barnhart, Cynthia Correia, Goncalo Homem de Almeida Univ Coimbra Dept Civil Engn P-3030788 Coimbra Portugal MIT Dept Civil & Environm Engn Cambridge MA 02139 USA Delft Univ Technol Dept Transport & Planning NL-2600 GA Delft Netherlands

Although one-way carsharing is suitable for more trip purposes than round-trip carsharing, many companies in the world operate only in the round-trip market. In this paper, we develop a method that optimizes the design of a one-way carsharing service between selected origin-destination pairs of an existing round-trip carsharing system. The goal is to supplement the established round-trip services with new one-way services and increase profitability. We develop an integer programming model to select the set of new one-way services and apply it to the case study of Boston, USA, considering only trips with one endpoint at a station in the round-trip Zipcar service network and the other endpoint at Logan Airport. The airport was chosen as a necessary endpoint for a one-way service because it is a very significant trip generator for which the round-trip carsharing is not suitable. Results show that these supplemental one-way services could be profitable. Enabling relocation operations between the existing round-trip stations and the Airport greatly improves the demand effectively satisfied, leads to an acceptable airport station size (in terms of the number of parking spots required), and is profitable;however, these benefits come with the need to manage relocation operations. (C) 2015 Elsevier Ltd. All rights reserved.

关键词： Round-trip carsharing One-way carsharing integer programming model

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Study on the Passenger Car Logistics Transportation Loading Problem of Company H

Study on the Passenger Car Logistics Transportation Loading ...

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International Conference on Logistics, Informatics and Service Sciences (LISS)

作者： Li, Wenyu Yu, Yangtao Li, Zhenping Beijing Wuzi Univ Dept Sch Informat Beijing Peoples R China

ISBN: (纸本)9781479918911

The passenger car logistics transportation loading problem of company H is investigated. Based on reasonable assumptions, the passenger car logistics transportation loading problem is transformed into a two-dimensional packing problem. Firstly, under the premise of considering the sizes of two types of car carriers and three kinds of passenger cars, and the stability requirements of car carriers, 36 kinds of possible loading modes of type 1-1 car carriers and 73 kinds of possible loading modes of type 1-2 car carriers are enumerated by using MATLAB program. Then, the integer programming model of passenger car logistics transportation loading problem is constructed to minimize the total transportation cost. A LINGO program is given to solve the model. Using the mathematical model and LINGO program, we obtain the number of two types of car carriers and the loading mode of each car carrier which company H can use to complete the given transport task. The results of this paper can provide a theoretical basis for the logistics company to make passenger car logistics transportation plans.

关键词： passenger car car carrier logistics transportation loading problem integer programming model

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An Overview of Global Routing

An Overview of Global Routing

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2015 International Conference and Workshop on Computing and Communication (IEMCON)

作者： Ghose, Rahul Chattopadhyay, Soummyo Priyo Das, Tiyasha Das, Tejes Saha, Ayoshna Inst Engn & Management Kolkata India

ISBN: (纸本)9781479969081

Global routing in VLSI (very large scale integration) design is one of the most challenging discrete optimization problems in computational theory. In this review paper of ours, we have presented a polynomial time algorithm for the global routing problem based on integer programming formulation with a theoretical approximation bound. The algorithm ensures that all routing demands are satisfied concurrently, and the overall cost is approximately minimized. Both serial and parallel implementation has been provided to develop several heuristics used to improve the quality of the solution and reduce running time. We provide computational results on two sets of well-known benchmarks and show that, with a certain set of heuristics, our new algorithms perform extremely well compared with other integer-programming models.

关键词： Global routing in VLSI design Approximation algorithms integer programming model

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