Optimization of Location Model of Capacitated Network

This study concerns with the research work on Location Model of Public Service Obligation State-Owned Company (PSO-SOC). Its aim is to develop an approach of making location decision on distribution facilities of such company, in which capacities of facilities are limited (capacitated facilities) and it deals with single commodity. Heuristic solution is proposed to modify established Add Algorithm, which is designed for uncapacitated facilities. The Network Representation is used to represent original problem of LocationModel. An example is provided to illustrate the proposed step-wise of solving the model

Tolling, Capacity Selection and Equilibrium Problems with Equilibrium Constraints

An Equilibrium problem with an equilibrium constraint is a mathematical construct that can be applied to private competition in highway networks. In this paper we consider the problem of finding a Nash Equilibrium regarding competition in toll pricing on a network utilising 2 alternative algorithms. In the first algorithm, we utilise a Gauss Siedel fixed point approach based on the cutting constraint algorithm for toll pricing. In the second algorithm, we extend an existing sequential linear complementarity approach for finding Nash equilibrium subject to Wardrop Equilibrium constraints. Finally we consider how the equilibrium may change between the Nash competitive equilibrium and a collusive equilibrium where the two players co-operate to form the equivalent of a monopoly operation

A HEURISTIC FIXED-CHARGE QUADRATIC ALGORITHM

Research Methods/ Statistical Methods,

A Tabu Search Heuristic Procedure for the Capacitated Facility Location Problem

A tabu search heuristic procedure for the capacitated facility location problem is developed, implemented and computationally tested. The heuristic procedure uses both short term and long term memories to perform the main search process as well as the diversification and intensification functions. Visited solutions are stored in a primogenitary linked quad tree as a long term memory. The recent iteration at which a facility changed its status is stored for each facility site as a short memory. Lower bounds on the decreases of total cost are used to measure the attractiveness of switching the status of facilities and are used to select a move in the main search process. A specialized transportation algorithm is developed and employed to exploit the problem structure in solving transportation problems. The performance of the heuristic procedure is tested through computational experiments using test problems from the literature and new test problems randomly generated. It found optimal solutions for a most all test problems used. As compared to the Lagrangean and the surrogate/Lagrangean heuristic methods, the tabu search heuristic procedure found much better solutions using much less CPU time.Capacitated facility location, Tabu search, Metaheuristics

Efficient heuristic algorithms for location of charging stations in electric vehicle routing problems

Indexación: Scopus.This work has been partially supported by CONICYT FONDECYT by grant 11150370, FONDEF IT17M10012 and the “Grupo de Logística y Transporte” at the Universidad del Bío-Bío.. This support is gratefully acknowledged.Eco-responsible transportation contributes at making a difference for companies devoted to product delivery operations. Two specific problems related to operations are the location of charging stations and the routing of electric vehicles. The first one involves locating new facilities on potential sites to minimise an objective function related to fixed and operational opening costs. The other one, electric vehicle routing problem, involves the consolidation of an electric-type fleet in order to meet a particular demand and some guidelines to optimise costs. It is determined by the distance travelled, considering the limited autonomy of the fleet, and can be restored by recharging its battery. The literature provides several solutions for locating and routing problems and contemplates restrictions that are closer to reality. However, there is an evident lack of techniques that addresses both issues simultaneously. The present article offers four solution strategies for the location of charging stations and a heuristic solution for fleet routing. The best results were obtained by applying the location strategy at the site of the client (relaxation of the VRP) to address the routing problem, but it must be considered that there are no displacements towards the recharges. Of all the other three proposals, K-means showed the best performance when locating the charging stations at the centroid of the cluster. © 2012-2018. National Institute for R and D in Informatics.https://sic.ici.ro/wp-content/uploads/2018/03/Art.-8-Issue-1-2018-SIC.pd