A Heuristic Programming Algorithm for Warehouse Location

A new heuristic programming method of solving a particular type of warehouse location problem is presented. The problem is to allocate K or less facilities to N possible locations so as to service M demand centers at minimum cost. The algorithm presented is suitable for hand calculation of medium-size problems (50 × 50) or when computerized will readily solve large-scale problems of the order of (600 × 600); i.e., 600 demand centers and 600 possible locations.     

Safety Investment Allocation by Dynamic Programming1

A two-phase model is proposed for determining and evaluating alternative safety investments. The first phase involves the analysis of safety problems by the use of Fault Tree Analysis. The resulting Fault Trees are then used to establish the probabilistic structure through which the returns of safety investments can be determined. This is integrated into a dynamic programming algorithm so that the variety of discrete alternatives can be evaluated under the constraints of a total safety budget.     

A Quadratic Facility Location Problem

This article treats the problem of locating multiple new facilities with respect to multiple existing facilities when there is an interchange of materials between new facilities and between new and existing ones. The “cost” of a solution to the location problem is given as a weighted sum of the square of the Euclidian distances traveled in the interchange of materials. Necessary and sufficient conditions for an optimum location are developed, resulting in the simultaneous solution of a set of linear equations in order to obtain the optimum location. The solution procedure is demonstrated with an example problem.     

Linear Programming Based Genetic Algorithm for the Unequal Area Facility Layout Problem

The facility layout problem (FLP) is generally defined as locating a set of departments in a facility with a given dimension. In this paper, a hybrid genetic algorithm (GA)/linear programming (LP) approach is proposed to solve the FLP on the continuous plane with unequal area departments. This version of the FLP is very difficult to solve optimally due to the large number of binary decision variables in mixed integer programming (MIP) models as well as the lack of tight lower bounds. In this paper, a new encoding scheme, called the location/shape representation, is developed to represent layouts in a GA. This encoding scheme represents relative department positions in the facility based on the centroids and orientations of departments. Once relative department positions are set by the GA, actual department locations and shapes are determined by solving an LP problem. Finally, the output of the LP solution is incorporated into the encoding scheme of the GA. Numerical results are provided for test problems with varying sizes and department shape constraints. The proposed approach is able to either improve on or find the previously best known solutions of several test problems.     

The Allocation of Federal Highway Safety Funds Using Dynamic Programming

Productivity in many governmental agencies is obtained by providing the maximum benefit to the citizenry given the budget constraint of the agency. This paper demonstrates a data collection procedure that produces the information necessary for measuring costs and benefits of spot highway safety improvements. Dynamic Programming is used to allocate the total available funds to produce the maximum benefit in terms of estimated savings of lives, injuries and property damage. A comparison is given between this optimal allocation and the results that would be obtained by using a maximum benefit to cost ratio first policy.     

A Review of the Discrete Facility Location Problem

In this paper we attempt to classify discrete facility location problems in the right perspective and propose discrete facility location problems that include： median problems, covering problems, center problems, multi-commodities problems and dynamic problems on the basis of former research by other scholars. We consider vehicle muting location problems, inventory-location problems and hub problems as a recent research field of discrete facility location problems according to literature from the last 10 years.     

The Uncapacitated Facility Location Problem With Primary and Secondary Facility Requirements

We consider the problem of locating uncapacitated facilities among a set of potential sites to minimize cost of serving a number of demand points each requiring service from two different facilities. This problem has many potential applications. One such application is location of emergency service facilities where it is desirable to have a primary and back-up service facility wthin a certain distance from every district An efficient solution procedure is developed. This procedure is tested on a number of problems and computational results are reported. It is compared to a state of the art commercial linear/integer programming package and found to be around two orders of magnitude faster than this package. It is also compared to a state of the art special purpose agorithm for the simple uncapacitated facility location problem to investigate the computational implications of introducing secondary service requirements. The model is used to illustrate the effect of considering secondary service on the spatial characteristics of the optimal set of locations. The model is further demonstrated on a “real life” example with 625 demand points and 30 potential facility locations.     

一种OFDM系统动态子载波比特和功率分配联合算法

提出一种多用户OFDM(orthogonal frequency division multiplexing)系统下行链路，具有信道变化实时性的动态子载波、比特和功率分配联合算法(UA)，在满足各个用户数据速率和BER要求的同时使总的发送功率最小。提出的算法与动态子载波分配算法(WSA)相比，计算复杂度相当，在移动信道环境下仿真结果表明性能有一定的改善。     

A Quantified Model for Facility Site Selection-Application to a Multiplant Location Problem

Present location theory ranges from lists of subjective factors to be used as guidelines on the one hand to mathematical models utilizing only monetary factors on the other. A void has existed with respect to using all relevant location information in a comprehensive location model. Such a model is presented in this paper. All factors, both subjective and those quantifiable, are evaluated, converted to consistent, dimensionless indices, and then combined to yield the location measure of a given site. These location measures may be used to select a single location or may serve as input to a second model which solves a multiplant location problem. The entire process has been programmed in FORTRAN IV and is currently in use.     

不确定环境下应急设施选址问题两阶段鲁棒优化模型

对于应急物流管理而言,应急物资集散中心选址是一个重要的决策要素。针对应急突发事件的不确定性特征,本文提出了一个应急设施选址问题两阶段鲁棒优化模型,以实现“预选址-重选址”两者的协同优化。第一阶段在需求和成本变动、设施损毁存在不确定因素的情况下,综合考虑选址策略在灾前规划、灾后反应、设施重建阶段的不同需求,建立了一种基于p-center的鲁棒“预选址”模型;第二阶段针对灾后新信息的获得,建立了一种基于反应式修复和调整策略的新建设施“重选址”模型。算例分析表明,本文模型对于应急设施选址问题比传统p-center模型更为合理有效     

A Dual-based Heuristic for the Simple Facility Location Problem With Stochastic Demand

This paper deals with a stochastic version of the simple facility location problem where the demands of customers are random variables. Under the assumption of step function type distribution of demands, the problem is shown to be approximated by a mixed 0-1 linear programming problem. A heuristic procedure is developed to solve the problem, which successfully extends the well known dual-based approach by Bilde & Krarup, and Erlenkotter. Computational results with 20 test problems are presented to demonstrate the effectiveness of the proposed heuristic.     

A Linear Programming Model with Shortage Costs for Energy Planning and Allocation

Since the energy shortage is only a recent phenomenon, most of the quantitative models for energy planning have assumed that the demands can always be met by increasing imports. In this paper, the concept of an energy shortage cost is introduced, and a quantitative energy model with shortages is developed to study the interfuel competition, and optimal allocation policies during an energy shortage. The solution is approached through linear programming methods. In addition to the societal shortage cost for energy, other special features of our model include consideration of all forms of energy resources and new technologies of energy production. The model is illustrated through a number of case studies on an economic region using realistic energy data. Through these applications the model is shown to be a useful tool to assess the impact of future energy shortages, higher fuel prices, introduction of newer technologies, and various allocation policies.     

基于区域分割的动态规划立体匹配算法

提出一种基于区域分割的动态规划立体匹配算法.首先参考图像经自适应多阈值切割之后,得到一个由区域组成的集合,并沿着各个闭合区域的边界进行动态规划跟踪,然后对于非匹配区域和区域内部分别作视差融合和视差插值处理,获得最终的稠密视差图.实验结果表明,该算法能够取得较为理想的效果,视差图横向“条纹”瑕疵和边界区域上的误匹配点明显减少,层次更加分明,整个视差图平滑性较好,匹配效率有了显著提高.     

基于利润最大化的奥运商业网点分布微观经济模型

本文首先通过多元统计分析发现了统计数据中的一般规律,并讨论了数据中所反映出的某些与常识不一致之处.在通过图论的有关知识确定观众进出体育场馆的模式之后,我们建立了一个简单实用的基于成本利润分析的整数规划模型.通过Lingo、Matlab软件的模拟,该模型与现实环境和有关经济理论拟合较好,可以为2008年奥运会迷你超市的设置提供一定的参考.     

基于利润最大化的奥运商业网点分布微观经济模型

本文首先通过多元统计分析发现了统计数据中的一般规律,并讨论了数据中所反映出的某些与常识不一致之处。在通过图论的有关知识确定观众进出体育场馆的模式之后,我们建立了一个简单实用的基于成本利润分析的整数规划模型。通过Lingo、Matlab软件的模拟,该模型与现实环境和有关经济理论拟合较好,可以为2008年奥运会迷你超市的设置提供一定的参考。     

A Dynamic Programming Model for Determining Continuous-Caster Configurations

In the steel industry the continuous casting machine, or caster, can be used to eliminate a number of processing steps associated with the traditional steel production sequence from ingot through blooms to finished product. A given continuous caster can produce only a small number of bloom thicknesses, which creates a problem for selecting those continuous-caster configurations which would maximize caster utilization. A dynamic programming model was developed to assist Bethlehem Steel personnel to determine that set of caster configurations which would maximize the cast bloom tonnage that could be processed through one of the finishing mills. Without the aid of such a model, selecting the highest productivity options presents a difficult exercise because of two conflicting considerations: (1) as the number of caster-produced bloom thicknesses increases, the caster setup time and configuration complexity increase; and (2) as the number of thicknesses decreases, less cast tonnage can be processed through the finishing mill because of reheat-furnace and cooling-bed limitations. The model results were transmitted to plant management and are being used in conjunction with other information to determine the most economic configuration.     

线性乘性规划的全局优化算法

本文研究线性乘性规划问题(LMP)的全局最优化算法,线性乘性规划问题在生产运输、工厂布局设计、超大规模集成电路芯片设计等方面有重要的应用。首先将LMP问题转化为等价规划问题(P1),然后利用参数线性化方法在相应的超矩形上求得问题(P1)的目标函数和约束函数线性下界估计,并提出了一个求线性乘性规划全局解的确定性全局优化算法,并证明了算法的收敛性。数值实验表明提出的方法是可行和有效的。     

基于工作负荷均衡的车辆拯救设施选址

交通事故车辆的拯救设施选址是车辆拯救服务的重要问题,选址不当易造成车辆拯救行业服务效率低下、市场行业的不规范、利益不均等一系列问题。针对这类问题,分析了俱乐部和政府引导两种服务模式下的拯救设施选址特点,并提出了针对车辆拯救的工作负荷概念。在不确定性救援路径行程时间条件下,建立以负荷均衡为目标的车辆拯救设施选址模型,以提高设施站点的运营效率和实现车辆拯救企业间的利益平衡。采用三种染色体形式的混合编码和随机模拟方法,设计基于遗传优化的求解算法。最后,通过仿真实例验证了算法的有效性。     

A Branch and Bound Algorithm for Use in Resource Allocation

This paper presents a resource allocation technique in the form of a branch and bound algorithm which optimizes the allocation at a specific point in time. The algorithm allows the user to attach individual performance ratings to each resource and weighting factors to each activity under consideration. A small sample problem is presented and solved to illustrate the use of the algorithm.     

A Dynamic Resource Allocation Model for A Machine Requirements Problem

This paper is concerned with the problem of determining the optimum number of machines to have in a production process. The problem is analyzed as a resource allocation problem involving the minimum cost allocation of limited floor space, capital budget, and available overtime among various types of machines. The dynamic nature of the problem is also included in the analysis. A deterministic mixed integer programming model is described. A numerical example is presented to illustrate the approach and its utility as an alternative way to address the machine requirements problem.