Facility Location Network Design Research Articles

Optimizing locations of waste transfer stations in rural areas.

Many studies have considered the location of rural waste transfer stations, but most have omitted the impact of transportation network conditions. Traffic accessibility must be considered in optimizing the location of rural waste transfer stations, which is an important difference from the location of rural waste transfer stations. On the basis of previous studies, this study will consider the impact of traffic network on the optimization locations of waste transfer station in the rural areas. The objective of this study was to ensure the minimum Euclidean distance between the waste transfer station and the population center is the maximum, minimize the garbage transportation cost of each population center, construction costs for waste transfer stations, construction and upgrade costs for roads on a traffic network. A multi-objective facility location-network design model and an improved multi-objective simulated annealing algorithm was used to solve the problem. A detailed practical case study was used to illustrate the application of the proposed mathematical model. The results show that transportation network plays an important role in facility location optimization, and the improvement of traffic network conditions can greatly reduce waste transportation costs.

A fuzzy capacitated facility location-network design model: A hybrid firefly and invasive weed optimization (FIWO) solution

Facility location-network design (FLND) problem, which determines the location of facilities and also communication links between the demand and facility nodes, is arisen from the combination of the facility location and network design problems. This paper deals with fuzzy capacitated facility location-network design model which aims to select the facilities and candidate links in a way that yield to minimize the total costs, containing: costs of opening facilities, link construction and transportation costs. In this study, several types of links have been considered for connecting two nodes in which their capacity, transportation and construction costs are distinct. Besides, the possibility of multiple link selection between two nodes and also the necessity of the existence of a facility in some nodes are considered. There are also several types of facilities which the budget for each type is unique. Moreover, to open the facilities and to construct the links, limited budgets are considered. As a result of the uncertainty in customers’ demand, an interactive fuzzy solution approach is applied. Because this problem is classified as an NP-hard class, a hybrid meta-heuristic algorithm based on Firefly and Invasive Weed Optimization (FIWO) is developed. Finally, the behavior of the model is tested, and the proposed algorithm’s performance is compared with some other solving methods.

Mixed integer optimization for the combined capacitated facility location-routing problem

Given a set of potential facilities (with individual opening cost and finite capacity) and a set of client demands, the capacitated Facility Location Problem (cFLP) consists in selecting a set of facilities to open and performing an assignment of demands to open facilities that minimize the sum of the facility opening cost, supplying cost and transportation/connection cost. This problem shares many similarities with the one consisting in minimizing the cost for opening a set of servers or replicas for storing a set of data objects (files) and connecting clients to facility locations so as to satisfy their demands. The multi-source dimension of the problem translates the situation where the same data object may be available simultaneously at different facility locations. When various data objects with different properties are available at (possibly multiple) opened facility locations, the problem shares the characteristics of the multi-product or multi-commodity model. On the other hand, the combination of the cFLP with the network design problem, referred to as the Capacitated Facility Location-Network Design Problem (cFLNDP), has been subject to several studies since the early 2000s. This (class of) problem(s) was initially motivated by the observation that when the (physical) network topology is determined endogenously, it may be more effective to change the configuration of the underlying network physical topology instead of locating additional facilities in order to account for the spatio-temporal variability in clients demands. However, in the context of communication networks, one does not require to physically rewire the network to obtain a new logical topology. Hence, in this paper we combine the capacitated multi-source multi-product facility location with the traffic routing problem and propose a mixed-integer program formulation. As dynamic routing offers the flexibility to re-configure routing tables entries and adapt routing decisions, our combined model also enables to dynamically re-allocate demands upon facility failure.

Persistent Homology applied to location problems

Different approaches to solve location problems in transport and logistics have been developed in the literature. This article introduces a new approach using the concept of persistent homology which has been proved to be an efficient method in topological data analysis; and has been served as an alternative new tool in many and various research areas such as image processing, material science and biological systems. Precisely, inspired by the notions of the first homology groups and the persistent homology which mainly describe the behaviour of connectivity relation between elements during a filtration of specific topological spaces; we develop a new method and approach for the treatment of facility location–network design problems.

A Lagrangian relaxation approach to fuzzy robust multi-objective facility location network design problem

This study considers a multi-objective combined budget constrained facility location/network design problem (FL/NDP) in which the system uncertainty is considered. The most obvious practical examples of the problem are territorial designing and locating of academies, airline networks, and medical service centers. In order to assure the network reliability versus uncertainty, an efficient robust optimization approach is applied to model the proposed problem. The formulation is minimizing the total expected costs, including, transshipment costs, facility location (FL) costs, fixed cost of road/link utilization as well as minimizing the total penalties of uncovered demand nodes. Then, in order to consider of several system uncertainty, the proposed model is changed to a fuzzy robust model by suitable approaches. An efficient Sub-gradient based Lagrangian relaxation algorithm is applied. In addition, a practical example is studied. At the following, a series of experiments, including several test problems, is designed and solved to evaluate of the performance of the algorithm. The obtained results emphasize that considering of practical factors (e.g., several uncertainties, system disruptions, and customer satisfaction) in modelling of the problem can lead to significant improvement of the system yield and subsequently more efficient utilization of the established network.

Study of Facility Location-network Design Problem in Presence of Facility Disruptions: a Case Study

Study of Facility Location-network Design Problem in Presence of Facility Disruptions: a Case Study

Facility Location-Network Design Problem: Reliability and Investment Budget Constraint

The simultaneous consideration of combined facility location and network design is an attractive empirical topic for locating public and private facilities and for reducing transportation costs. Moreover, applying a reliable facility location problem is one of the most effective ways to protect against occasional failures of the system, because of considering unexpected failures and possible customer reassignment when locating facilities. Accordingly, this study concerns a reliable combined facility location–network design problem regarding the investment budget constraint and proposes a mixed integer nonlinear programming formulation to model this constraint. The proposed model is linearized by suitable techniques. Also, a practical case study subject to sustainable design in urban health care development is presented in detail to illustrate the application of the proposed mathematical model. Finally, a sensitivity analysis is conducted to provide insights into the behavior of the proposed model in response to the changes of key parameters of the problem.

Developing Network Location Model in Uncertainty Mode (Robust Mode)

In this research, facility location problem-network design under uncertainty robust mode has been discussed. In this regard a model will be developed, so that the uncertainty in parameters such as demand and problem’s various costs considered. Facility location-network design, unlike classical facility location models, which are assumed that network structure is pre-defined and pre-specified, will also decide on the structure of the network.

Modeling the budget-constrained dynamic uncapacitated facility location–network design problem and solving it via two efficient heuristics: A case study of health care

This paper presents a model for the budget-constrained dynamic (multi-period) uncapacitated facility location–network design problem (DUFLNDP). This problem is concerned with the determination of the optimal locations of facilities and the design of the underlying network simultaneously in which there is a budget constraint on investment for opening the facilities and constructing (activating) links for each time period during the planning horizon. The objective is to minimize the total travel costs for customers and operating costs for facilities and network links. Furthermore, a greedy heuristic and a fix-and-optimize heuristic based on simulated annealing and exact methods (Branch & Bound and cutting methods) are proposed to solve the model. The performance of the proposed algorithms were tested on extensive randomly generated instances and compared with the CPLEX solver. The budget-constrained DU FLNDP has a lot of important applications which as one of them, the accessibility of health care facilities in Illam Province of Iran is investigated.

Improving access to health facilities in Nouna district, Burkina Faso

The Nouna health district in Burkina Faso, has a population of approximately 275,000 people living in 281 villages, and is served by 25 health facilities, as of 2006. For many people, the time and effort required in traveling to a health facility, which may demand a journey of many kilometers over poor roads on foot, is a deterrent to seeking proper medical care. In this study we examine how access to health facilities in Nouna may be improved by considering the configuration of the road network in addition to the locations of the facilities. We model the situation as a facility location–network design problem and draw conclusions about how best to improve the physical access of the health facilities. Our model shows the extent to which access can be improved when the road network is considered along with facility locations, in contrast to facility locations considered alone.

A hybrid model for multi-objective capacitated facility location network design problem

One of the primary concerns on many traditional capacitated facility location/network problems is to consider transportation and setup facilities in one single objective function. This simple assumption may lead to misleading solutions since the cost of transportation is normally considered for a short period time and, obviously, the higher cost of setting up the facilities may reduce the importance of the transportation cost/network. In this paper, we introduce capacitated facility location/network design problem (CFLNDP) with two separate objective functions in forms of multi-objective with limited capacity. The proposed model is solved using a new hybrid algorithm where there are two stages. In the first stage, locations of facilities and design of fundamental network are determined and in the second stage demands are allocated to the facilities. The resulted multi-objective problem is solved using Lexicography method for a well-known example from the literature with 21 node instances. We study the behaviour of the resulted problem under different scenarios in order to gain insight into the behaviour of the model in response to changes in key problem parameters.