Today’s logistic systems in companies depend on optimum solutions of Facility Location-Allocation (FLA) problems in order to minimize cost values the company is dealing with. Therefore, FLA plays an important role in nowadays business environment. In this paper, a Hybrid Genetic Algorithm (HGA) is proposed to solve FLA. The HGA is a combination of Genetic Algorithm and Tabu Search while NSGA II...

This paper proposes a new lower bounding procedure for the Uncapacitated Single Allocation p-Hub Median Problem based on Lagrangean relaxation. For solving the resulting Lagrangean subproblem, the given problem structure is exploited: it can be decomposed into smaller subproblems that can be solved efficiently by combinatorial algorithms. Our computational experiments for some benchmark instanc...

In order to model capacitated location–allocation problem with fuzzy demands, three types of fuzzy programming models – fuzzy expected cost minimization model, fuzzy a-cost minimization model, and credibility maximization model – are proposed according to different decision criteria. For solving these models, some hybrid intelligent algorithms are also designed. Finally, several numerical exper...

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The design of hub-and-spoke transport networks is a strategic planning problem, as the choice of hub locations has to remain unchanged for long time periods. However, strikes, disasters or traffic breakdown can lead to the unavailability of a hub for a short period of time. Therefore it is important to consider such events already in the planning phase, so that a proper reaction is possible; on...

This paper presents a new mathematical model for location-allocation problem considering uncertain parameter. In real-world cases, demand, distance, traveling time or any parameters in classical models may change over the period of time. So, considering uncertainty yields more flexibility for the results and its applications. In our study, environmental uncertainty is described by discrete scen...

In this chapter, we present a procedure that seeks the global minimum for the capacitated Euclidean location-allocation problem which is defined as follows. Given the fixed location of m existing facilities or customers on a continuous plane and their associated demands, we wish to determine the location of n new facilities or sources with known capacities, and the allocation of its supply, in ...

This paper proposes a bi-objective model for the facility location problem under a congestion system. The idea of the model is motivated by applications of locating servers in bank automated teller machines (ATMS), communication networks, and so on. This model can be specifically considered for situations in which fixed service facilities are congested by stochastic demand within queueing frame...