共查询到20条相似文献,搜索用时 31 毫秒
1.
设施选址问题是组合优化中重要问题之一。动态设施选址问题是传统设施选址问题的推广,其中度量空间中设施的开设费用和顾客的需求均随着时间的变化而变化。更多地,经典设施选址问题假设所有的顾客都需要被服务。在这个模型假设下,所有的顾客都需要服务。但事实上,有时为服务距离较远的顾客,需要单独开设设施,导致了资源的浪费。因此,在模型设置中,可以允许一些固定数目的顾客不被服务 (带异常点的设施选址问题),此外也可以通过支付一些顾客的惩罚费用以达到不服务的目的 (带惩罚的设施选址问题)。本文将综合以上两种鲁棒设置考虑同时带有异常点和惩罚的动态设施选址问题,通过原始-对偶框架得到近似比为3的近似算法。 相似文献
2.
《European Journal of Operational Research》1986,24(2):239-246
The problem considered in this paper involves the location of an undesirable facility such that the maximum weighted inverse square distance from the facility to n given points is minimized. The region in which the facility is to be located is bounded and contains the n points with which the facility to be located will interact. Applications can include siting an undesirable facility that produces some form of pollutant such as radiation, noise and some gases. Any problem that involves the location of a facility that emits pollutants whose concentrations follow the inverse square law is a candidate for the use of this work. A mathematical programming algorithm is developed for the situation in which the location problem involves a convex polygonal region. An interactive computer graphics approach is described for the case when the location problem involves a general region. 相似文献
3.
This paper considers the problem of locating a single facility in the presence of a line barrier that occurs randomly on a given horizontal route on the plane. The objective is to locate this new facility such that the sum of the expected rectilinear distances from the facility to the demand points in the presence of the probabilistic barrier is minimized. Some properties of the problem are reported, a solution algorithm is provided with an example problem, and some future extensions to the problem are discussed. 相似文献
4.
In this paper we propose a new model for the p-median problem. In the standard p-median problem it is assumed that each demand point is served by the closest facility. In many situations (for example, when demand points are communities of customers and each customer makes his own selection of the facility) demand is divided among the facilities. Each customer selects a facility which is not necessarily the closest one. In the gravity p-median problem it is assumed that customers divide their patronage among the facilities with the probability that a customer patronizes a facility being proportional to the attractiveness of that facility and to a decreasing utility function of the distance to the facility. 相似文献
5.
本文研究带惩罚的动态设施选址问题,在该问题中假设不同时段内设施的开放费用、用户的需求及连接费用可以不相同,而且允许用户的需求不被满足,但是要有惩罚.对此问题我们给出了第-个近似比为1.8526的原始对偶(组合)算法. 相似文献
6.
The facility layout problem is concerned with finding the most efficient arrangement of a given number of departments with unequal area requirements within a facility. The facility layout problem is a hard problem, and therefore, exact solution methods are only feasible for small or greatly restricted problems. In this paper, we propose a spring-embedding approach that unlike previous approaches results in a model that is convex. Numerical results demonstrating the potential of our model and the efficiency of our solution procedure are presented. 相似文献
7.
《European Journal of Operational Research》1987,29(3):229-251
In this paper, the facility layout problem is surveyed. Various formulations of the facility layout problem and the algorithms for solving this problem are presented. Twelve heuristic algorithms are compared on the basis of their performance with respect to eight test problems commonly used in the literature. Certain issues related to the facility layout problem and some aspects of the machine layout problem in flexible manufacturing systems are also presented. 相似文献
8.
We consider the competitive facility location problem in which two competing sides (the Leader and the Follower) open in succession
their facilities, and each consumer chooses one of the open facilities basing on its own preferences. The problem amounts
to choosing the Leader’s facility locations so that to obtain maximal profit taking into account the subsequent facility location
by the Follower who also aims to obtain maximal profit. We state the problem as a two-level integer programming problem. A
method is proposed for calculating an upper bound for the maximal profit of the Leader. The corresponding algorithm amounts
to constructing the classical maximum facility location problem and finding an optimal solution to it. Simultaneously with
calculating an upper bound we construct an initial approximate solution to the competitive facility location problem. We propose
some local search algorithms for improving the initial approximate solutions. We include the results of some simulations with
the proposed algorithms, which enable us to estimate the precision of the resulting approximate solutions and give a comparative
estimate for the quality of the algorithms under consideration for constructing the approximate solutions to the problem. 相似文献
9.
在震后救援初期,构建合理的应急物流网络,对于快速有效供应应急物资、减轻灾情具有重大价值。在传统可靠性选址问题与应急设施选址-分配问题的基础上,考虑震后救援初期的阶段性特征、设施中断情景、多品种模糊需求、设施能力限制等因素,建立了一个适用于震后救援初期的应急设施选址-分配模型。通过三角模糊数的期望值公式将模糊需求去模糊化。在此基础上,考虑模型特点,设计了一种整数编码的混合遗传算法。最后,以5·12汶川地震为背景,构造算例进行数值仿真。验证了所提模型和算法。结果表明:考虑设施中断情景后,即使系统中的部分设施失效,整个网络仍能较好运行,且优化结果更具可靠性和稳健性。 相似文献
10.
考虑软容量约束的动态设施选址问题.假设设施的开放费用及连接费用都与时间有关,而且每一个设施均有容量约束.对此问题给出了第一个近似比为6的原始对偶(组合)算法.运行贪婪增加程序后,近似比进一步改进到3.7052. 相似文献
11.
《European Journal of Operational Research》2006,174(3):1414-1426
The effect of workflow interference is a major concern in facility layout design. Yet, despite the extensive amount of research conducted on the facility layout problem, very little has been done to incorporate interference as part of an overall approach to layout design. This paper examines the impact of workflow interference considerations on facility layout analyses. Linear and nonlinear integer programming formulations of the problem are presented. The structural properties of the resulting formulations, as applied to facility design, are investigated. Finally, a multi-objective approach to facility layout design is presented, incorporating the traditional distance-based objective with that of workflow interference. 相似文献
12.
The universal facility location problem generalizes several classical facility location problems, such as the uncapacitated facility location problem and the capacitated location problem (both hard and soft capacities). In the universal facility location problem, we are given a set of demand points and a set of facilities. We wish to assign the demands to facilities such that the total service as well as facility cost is minimized. The service cost is proportional to the distance that each unit of the demand has to travel to its assigned facility. The open cost of facility i depends on the amount z of demand assigned to i and is given by a cost function \(f_i(z)\). In this work, we extend the universal facility location problem to include linear penalties, where we pay certain penalty cost whenever we refuse serving some demand points. As our main contribution, we present a (\(7.88+\epsilon \))-approximation local search algorithm for this problem. 相似文献
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14.
《European Journal of Operational Research》1999,115(2):285-299
This paper presents exact and heuristic solution procedures for a multiproduct capacitated facility location (MPCFL) problem in which the demand for a number of different product families must be supplied from a set of facility sites, and each site offers a choice of facility types exhibiting different capacities. MPCFL generalizes both the uncapacitated (or simple) facility location (UFL) problem and the pure-integer capacitated facility location problem. We define a branch-and-bound algorithm for MPCFL that utilizes bounds formed by a Lagrangian relaxation of MPCFL which decomposes the problem into UFL subproblems and easily solvable 0-1 knapsack subproblems. The UFL subproblems are solved by the dual-based procedure of Erlenkotter. We also present a subgradient optimization-Lagrangian relaxation-based heuristic for MPCFL. Computational experience with the algorithm and heuristic are reported. The MPCFL heuristic is seen to be extremely effective, generating solutions to the test problems that are on average within 2% of optimality, and the branch-and-bound algorithm is successful in solving all of the test problems to optimality. 相似文献
15.
Ibolya Jankovits Chaomin Luo Miguel F. Anjos Anthony Vannelli 《European Journal of Operational Research》2011,214(2):199-215
The unequal-areas facility layout problem is concerned with finding the optimal arrangement of a given number of non-overlapping indivisible departments with unequal area requirements within a facility. We present a convex-optimisation-based framework for efficiently finding competitive solutions for this problem. The framework is based on the combination of two mathematical programming models. The first model is a convex relaxation of the layout problem that establishes the relative position of the departments within the facility, and the second model uses semidefinite optimisation to determine the final layout. Aspect ratio constraints, frequently used in facility layout methods to restrict the occurrence of overly long and narrow departments in the computed layouts, are taken into account by both models. We present computational results showing that the proposed framework consistently produces competitive, and often improved, layouts for well-known large instances when compared with other approaches in the literature. 相似文献
16.
E Melachrinoudis 《Applied Mathematical Modelling》1985,9(5):365-369
This paper deals with the problem of placing an undesirable but necessary piece of equipment, process or facility into a working environment. Locating a piece of equipment that produces contaminants or creates stresses for nearby workers, placing a storage facility for flammable materials or locating hazardous waste in the workroom environment, are all typical examples of the undesirable facility location problem. The degree of undesirability between an existing facility or worker and the new undesirable entity is reflected through a weighting factor. The problem is formally defined to be the selection of a location within the convex region that maximizes the minimum weighted Euclidean distance with respect to all existing facilities. A ‘Maximin’ model is formulated and two solution procedures introduced. A geometrical approach and an algorithmic approach are described in detail. An example is provided for each solution procedure and the computational efficiency of the algorithm is discussed and illustrated. 相似文献
17.
Jack Brimberg H. Taghizadeh Kakhki George O. Wesolowsky 《Annals of Operations Research》2003,122(1-4):87-102
This paper investigates a new variation in the continuous single facility location problem. Specifically, we address the problem of locating a new facility on a plane with different distance norms on different sides of a boundary line. Special cases and extensions of the problem, where there are more than two regions are also discussed. Finally, by investigating the properties of the models, efficient solution procedures are proposed. 相似文献
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19.
The basic problem is to locate a linear facility to minimize the sume of weighted shortest Euclidean distances from demand points to the facility. We extend the analysis to locating a constrained linear facility, a radial facility, a linear facility where distances are rectangular and a linear facility under the minimax criterion. Each case is shown to admit a simple solution technique. 相似文献
20.
Isaac F. Fernandes Daniel Aloise Dario J. Aloise Pierre Hansen Leo Liberti 《Optimization Letters》2014,8(2):407-424
The objective in the continuous facility location problem with limited distances is to minimize the sum of distance functions from the facility to the customers, but with a limit on each of the distances, after which the corresponding function becomes constant. The problem has applications in situations where the service provided by the facility is insensitive after a given threshold distance. In this paper, we propose a global optimization algorithm for the case in which there are in addition lower and upper bounds on the numbers of customers served. 相似文献