2015 Informs Annual Meeting

SA69

INFORMS Philadelphia – 2015

SA71 71-Room 202B, CC Transportation Network Analysis and Optimization Sponsor: TSL/Urban Transportation Sponsored Session Chair: Andres Medaglia, Professor, Universidad de los Andes, Cra 1 Este No 19A - 40, Bogota, Colombia, amedagli@uniandes.edu.co 1 - On the Robust Shortest Path Problem: A Pulse Algorithm Approach Daniel Duque, Instructor, Universidad de los Andes, Cr 1E N 19A- 40, Bogota, Colombia, d.duque25@uniandes.edu.co, Andres Medaglia In this variant of the robust shortest path problem, the cost of traversing an arc is given by a discrete set of scenarios. The problem is then to find a (robust) path that takes into account the information arising from the multiple cost realizations of the possible scenarios. To account for a robust path, we adopt the bw- robustness criterion, which ameliorates the dramatic role played by the worst case analysis. To solve the problem, we extend the pulse algorithm, a general-purpose solution strategy that has been used on shortest path problems with side constraints. The proposed algorithm compares favorably against an integer programming approach both in terms of speed and scalability. 2 - Reliability of Interdependent Urban Infrastructure Network: Failure Propagation and Consequential Social Impact Liqun Lu, UIUC, United States of America, liqunlu2@illinois.edu, Yanfeng Ouyang, Xin Wang Modern city relies on a network of multiple interdependent infrastructure systems, hence more vulnerable. Random or premeditated infrastructure disruption can propagate to large areas and cause social disasters. The system reliability is investigated under both deterministic and stochastic disruption propagation and social impacts are evaluated by a user equilibrium model. 3 - Lagrangian Relaxation Solution Approach for the Vehicle Routing Problem with Pickup and Delivery Monirehalsadat Mahmoudi, Arizona State University, School of Sustainable Engineering and the Built Environment, Tempe, AZ, United States of America, mmahmoudi@asu.edu, Xuesong Zhou We propose a new time-discretized multi-commodity network flow model for the pickup and delivery problem with time windows based on the integration of vehicles’ carrying-states within space-time transportation networks. By a Lagrangian relaxation approach, the primal multi-vehicle routing problem is decomposed to a sequence of single vehicle routing sub-problems with Lagrangian multipliers for individual passengers’ request, each can be solved by a forward dynamic programming solution algorithm. 4 - Combined Maintenance-routing Optimization: The Case of a Water Utility Andres Medaglia, Professor, Universidad de los Andes, Cra 1 Este No 19A - 40, Bogota, Colombia, amedagli@uniandes.edu.co, Daniel Duque, Raha Akhavan-Tabatabaei, John E. Fontecha, Juan Pablo Rodriguez The combined maintenance-routing optimization problem deals with planning and scheduling maintenance operations for a set of geographically-distributed sites that are subject to non-deterministic failures. To solve this problem, a maintenance model determines the optimal time to perform preventive maintenance operations for each site; while a routing optimization engine schedules visits of a set of technicians that perform the operations. We present a case study in the city of Bogot·, where the water utility needs to perform maintenance operations to prevent sediment-related blockages of the sewer system.

5 - Facility Location Problem Considering Time Window and Land use Plan using GIS Eunsu Lee, Assistant Professor, New Jersey City University, 2039 John F. Kennedy Blvd, Jersey City, NJ, 07305, United States of America, elee3@njcu.edu, Sumadhur Shakya, Alan Dybing This paper investigates the facility location problem through network space, considering traversable truck roads, thereby providing a strategic decision for identifying a depot location in consideration of vehicle routings from a real application. This study provides a ready-to-use example of how to adopt state-of- the-art spatial technology and operations research using Geographic Information Systems (GIS), and bring it to state-of-practice.

SA69 69-Room 201C, CC

Facility Location and Inventory Routing Sponsor: Transportation, Science and Logistics Sponsored Session

Chair: Natashia Boland, Georgia Institute of Technology, 755 Ferst Drive, NW, Atlanta, GA, 30332-0205, United States of America, natashia.boland@isye.gatech.edu 1 - Facility Location Design under Continuous Traffic Equilibrium Zhaodong Wang, University of Illinois, 205 N. Mathews Ave, Urbana, IL, United States of America,zwang137@illinois.edu, Yanfeng Ouyang This paper proposes both a continuum approximation model and a discrete mixed-integer program model to solve the facility location problem under traffic congestion in continuous space. Customized algorithms are developed and analytical properties are presented. Numerical examples show the advantages of the continuous models and shed managerial insights. 2 - Winter is Coming: A Robust Optimization Approach to Inventory Routing Joel Tay, Graduate Student, Operations Research Center, MIT, 77 Massachusetts Ave, Bldg. E40-149, Cambridge, MA, 02139, United States of America, joeltay@mit.edu, Swati Gupta, Dimitris Bertsimas We consider the finite horizon inventory routing problem with uncertain demand, e.g. supplying residential heating oil to customers. Current techniques that solve this problem with stochastic demand do not scale to real-world data sizes. We propose a MIP formulation using robust optimization that is made tractable with heuristic route selection, warm starts and column generation. We show promising computational results that demonstrate scalability to real-world applications. 3 - A Matheuristic for the Multi-vehicle Inventory Routing Problem Natashia Boland, Georgia Institute of Technology, 755 Ferst Drive, NW, Atlanta, GA, 30332-0205, United States of America, natashia.boland@isye.gatech.edu, Cristina Archer, Grazia Speranza We consider the inventory routing problem in which a supplier must replenish a set of customers using a limited fleet of capacitated vehicles over a discrete time horizon. The goal is to minimize the total cost of the distribution, comprising the inventory costs at supplier and customers, and the routing cost. We present a matheuristic, combining tabu search and integer programming formulations. Extensive computational experiments on benchmark instances show the effectiveness of the method. SA70 70-Room 202A, CC Railway Applications Section Student Paper Award Sponsor: Railway Applications Sponsored Session Chair: April Kuo, BNSF Railway, 2400 Western Center Blvd., Fort Worth, TX, United States of America, April.Kuo@BNSF.com 1 - Railway Applications Student Paper Award April Kuo, BNSF Railway, 2400 Western Center Blvd., Fort Worth, TX, United States of America, April.Kuo@BNSF.com Rail Applications Section (RAS) sponsored a student research paper contest on analytics and decision making in railway applications. Papers must advance the application or theory of OR/MS for improvement of freight or passenger railway transportation, and it must represent original research that has not been published elsewhere by the time it is submitted. Authors of the First, Second and Third Place award winning papers will present their papers in this session.

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