We present an approximation algorithm for the maximization version of the two level uncapacitated facility location problem achieving a performance guarantee of 0.47. The main idea is to reduce the problem to a special case of MAX SAT, for which an approximation algorithm based on randomized rounding is presented.

In the two-stage capacitated facility location problem a single product is produced at some plants in order to satisfy customer demands. The product is transported from these plants to some depots and then to the customers. The capacities of the plants and depots are limited. The aim is to select cost minimizing locations from a set of potential plants and depots. This cost includes fixed cost ...

We consider a generalization of the uncapacitated facility location problem that occurs in planning of optical access networks in telecommunications. Clients are connected to open facilities via depthbounded trees. The total demand of clients served by a tree must not exceed a given tree capacity. We investigate a framework for combining facility location algorithms with a tree-based clustering...

Benders is one of the most famous decomposition tools for Mathematical Programming, and it is the method of choice e.g., in Mixed-Integer Stochastic Programming. Its hallmark is the capability of decomposing certain types of models into smaller subproblems, each of which can be solved individually to produce local information (notably, cutting planes) to be exploited by a centralized “master” p...

Facility location-allocation (FLA) problem, which has been proved to be a valuable method in siting service facility, is widely used in real life, such as emergency service systems, telecommunication networks, public services, etc. However, in real-world situations, the decision maker often lack the information about the customers’ demands, which leads to the FLA problem in uncertain environmen...

We present a multi-exchange local search algorithm for approximating the capacitated facility location problem (CFLP), where a new local improvement operation is introduced that possibly exchanges multiple facilities simultaneously. We give a tight analysis for our algorithm and show that the performance guarantee of the algorithm is between 3+2 √ 2− 2 and 3+2√2+ 2 for any given constant 2 > 0....

Most facility location problems are computationally hard to solve. The standard technique for solving these problems is branch-and-bound. To keep the size of the branch-and-bound tree as small as possible it is important to obtain a good lower bound on the optimal solution by deriving strong linear relaxations. One way of strengthening the linear relaxation is by adding inequalities that de ne ...

Location-Routing Problem (LRP) is related to logistics system of supply chain. In LRP, aims are facility location problem and vehicle routing problem that are considered simultaneously. As shown in recent researches, the costs in distribution systems may be excessive if routes are ignored when locating depots. In this paper, a heuristic method in four phases is developed to solve Capacitated Lo...

in this paper, the capacitated location-routing problem with fuzzy demands (clrp-fd) is considered. the clrp-fd is composed of two well-known problems: facility location problem and vehicle routing problem. the problem has many real-life applications of which some have been addressed in the literature such as management of hazardous wastes and food and drink distribution. in clrp-fd, a set of c...

In this paper we present a discretization reformulation technique in the context of a facility location problem with modular link costs. We present a ‘traditional’ model and a straightforward discretized model with a general objective function. The linear relaxation bounds provided by both formulations are compared. Furthermore, we state that a restricted version of the discretized model gives ...