基于中心化存储和横向转运的选址——库存联合决策模型

针对单一产品、单周期、单一供应商、多配送中心、供应商和需求点位置已知的情况,假定（Q,R）库存检查策略、给定备选地址、无容量约束、各需求点的需求完全独立且均服从正态分布、配送中心级和需求级同时采取中心化安全库存策略、允许配送中心间及同一配送线路内的需求点间通过横向转运对缺货进行瞬间补充、不计缺货成本和转运时间,构建了二层规划模型。上层规划解决选址及需求点的分配问题;下层规划确定配送中心级和需求级的中心化存储方案。发现如果考虑库存持有成本、转运成本等因素的影响,安全库存的集中存放策略并不是聚集在某一个地方,而是在多个地方进行有限、适度的集聚,其成本更低。     

基于遗传算法和模糊综合评价法物流配送中心选址研究

本文给出了关于配送中心选址的0-1混合整数线性规划模型,该模型要求在一些已知的备选点中选出一定数目的地点作为配送中心;并求出配送网络中的物流量,使配送网络总费用最小.由于这类模型属于NP难问题,为更好的求解此类问题,提出了定量化的遗传算法与定性化的模糊综合评价法相结合来确定配送中心地址的方法.     

A multiobjective modeling approach to locating incinerators

The location of hazardous material incineration facilities is an important problem due to the environmental, social, and economic impacts that they impose. The costs associated with the facilities and the risks placed on nearby populations are important concerns as are the distributions of these costs and risks. This paper introduces a mixed-integer, multiobjective programming approach to identify the locations and capacities of such facilities. The approach incorporates a Gaussian dispersion model and a multiobjective optimization model in a GIS-based interactive decision support system that planners can access via the Internet. The proposed approach is demonstrated via a case study in central Portugal where the national government has decided to locate a large facility for the incineration of hazardous industrial waste. Due to intense local and national opposition, construction of the facility has been delayed. The system has been designed so that it can be used by decision makers with no special training in dispersion modeling, multiobjective programming, or GIS.     

基于遗传算法的分销配送网络模型及求解

从供应链的集成和协调的角度出发,提出了在单工厂、多产品、多分销中心、多客户环境下,考虑需求分配的分销网络优化设计模型。模型体现了在设计分销网络时,根据各客户区对不同产品各种费用情况,合理地选择分销中心并将各客户区对不同产品的需求分配到各个分销中心,以降低分销环节的总费用。针对该模型,通过遗传算法,选择恰当的编码方法,快速求解模型,并通过实例验证了优化模型的正确性和算法的有效性。     

Social enterprise factory location and allocation model: Small scale manufacturing for East Africa

The manufacturing location decision for social enterprises that work in the context of sustainable development is rarely based on a quantitative, analytical process. As a result, decisions may be far from profit-maximizing. Location and allocation optimization models have the potential to improve decisions and thus enable such enterprises to scale up their business as well as their impact. We develop and explain a single-period single-factory model, and also a two-echelon location and allocation model, to provide enterprises with information about optimal factory locations, and with future demand allocations and capacity-changing decision information. We apply the models to a company that manufactures and distributes solar cookers in East Africa. Our results illustrate that quantitative location and allocation models can significantly affect social enterprises by improving profitability. The case study shows strong cost-reduction potential of local manufacturing in developing countries due to high transportation costs for small production volumes. We discuss this model-recommended decision by weighing it against associated opportunities and risks. This paper aims to enable and encourage social and sustainability-oriented manufacturing enterprises to apply operations research methods in their strategic factory location decision-making.     

基于遗传算法的配送中心选址及配送区域划分问题研究

在现有研究的基础上,建立了多个配送中心的选址及配送区域划分模型,在模型建立过程中既考虑了配送中心到需求点之间的距离、道路流量与可靠性等因素,也考虑了配送中心自身及其周围的环境因素,结合层次分析法,将这些因素转换为综合成本,使模型更具现实意义。采用遗传算法求解,使该问题的求解过程得到简化。最后用实例对模型进行了验证分析,说明该模型的合理性。     

基于顾客满意度的多目标配送中心选址方法研究

随着配送中心的发展和物流业经营理念的转变,为顾客提供的服务水平对企业的影响越来越重要。在传统的选址模型基础上,提出了一种立足配送中心和顾客两方面的选址模型,以顾客满意度来测量配送中心为顾客提供的服务水平,顾客等待时间的长短对其满意度产生直接影响,通过配送中心可以满足客户要求的时间长短来测量顾客满意度,同时建立了以物流成本最小化和顾客满意度最大化为目标的配送中心选址多目标模型,并提供了模型相应的求解方法。     

基于混合集合规划的多场景应急设施选址优化

多场景应急设施选址问题具有约束复杂、时效性强、规划周期短等特点。以混合集合规划为算法框架的自然约束语言NCL能对该问题进行建模与求解。以一个典型多场景应急设施选址问题为例,证明了NCL可有效求解该类问题。     

基于组合熵权的军事工程物资保障中心优化选址模型研究

针对军事工程保障中心选址问题,首先通过分析影响军事工程物资保障中心选址的12个指标,在此基础上,运用熵权理论圈定各评判指标的客观权重,最后利用贴近度算法对各选址方案进行排序,实现保障中心的优化选址。     

基于二层规划可直接利用品逆向物流网络优化

在可直接再利用品逆向物流网络现有研究的基础上,提出了一种既考虑了运输费用和固定投资费用之间的平衡（上层目标）,又考虑了客户的自由选址行为（下层目标）的二层规划模型,并给出了具体解法,进行了数值分析,得到了满意的结果。     

Network flow-based strategies for identifying rail park-and-ride facility locations

Many cities are considering introducing or expanding rail service in an effort to diversify their modal splits. Park-and-rides are integral to this strategy because they represent private auto users’ access points to the system. Proper placement of such facilities is a strategic location decision, as it can conceivably decrease vehicular traffic on congested roadways while benefiting users. This paper models the decision to locate park-and-ride facilities in a network flow-based framework. From this perspective, optimal placement occurs at locations where vehicles will encounter facilities early during their journeys to a centralized area or major activity center. Locating park-and-rides in this fashion maximizes the chances of removing users from the network. These elements are demonstrated in three hypothetical placement scenarios that make use of synthetic network and traffic flow data. Results illustrate the functionality of our approach for identifying park-and-ride candidate locations. Lastly, implications of our work are discussed in light of broader planning concerns and practical demands on rail facility location.     

连锁企业配送中心选址的两阶段模型研究

利用定性因素与定量因素相结合的方法研究了连锁企业物流配送中心选扯问题。首先在分析配送中心选址的定性因素的基础上,利用灰局势决策方法筛出候选点;然后在定量模型中,充分考虑连锁经营的特点,以配送服务的可靠性最大化为目标,以配送总成本为约束条件,建立了连锁企业配送中心选址的优化模型,从而得到连锁企业配送中心选址的定量方法。     

有竞争的物流配送中心选址模型研究

文章结合迭代算法、AHP和目标规划方法,在已有的关于有竞争的物流配送中心选址问题的研究成果上进行改进,进行了简单的研究。首先根据配送中心与顾客距离计算新配送中心的最大市场占有率,通过迭代算法获得一些相对较优备选地址,然后通过调查得出候选地址的相关信息,通过层次分析法评估各个备选地址的综合水平,最后通过多目标规划来寻找最好的位置建立物流配送中心,文章主要运用MATLAB,yaahp进行求解。     

考虑交通区位的物流配送中心选址模型及求解

从交通运输系统的角度出发,物流配送中心选址在考虑物流规划部门与客户之间利益分配问题的基础上。还应该考虑到交通区位优势给物流配送中心运营带来的便利性。在已有双层规划模型的基础上进行改进,通过在模型中设立相关参数来描述交通区位产生的影响。建立了考虑交通区位的物流配送中心选址双层规划模型,同时还考虑到竞争的存在。笔者设计了基于遗传算法的模型求解算法,最后通过一算例来对比验证模型及其算法的可行性。在物流配送中心选址时利用交通区位优势能大大提高其运营效率及效益。     

电子商务环境下的物流配送中心选址模型

电子商务环境下的物流配送中心选址是个很复杂的问题,涉及的因素很多。本文分析了电子商务环境下物流配送的特点,基于成本最小化的基础上建立了选址模型,与传统的选址模型进行了比较;并通过费用最小化确定配送中心的数量、资源点与配送中心、配送中心与用户的供需关系。     

物流系统设施区位模型研究

本文系统介绍了以降低成本与提高服务效率为目标的传统物流系统设施区位模型即运输成本最小化模型与服务效率模型的发展与特点。作者认为确定性模型向不确定性模型演化是运输成本最小化模型发展的总趋势，服务效率模型包括以建设成本最小化为目标的完全覆盖模型和最大覆盖模型两类：在此基础上，介绍了近年来在供应链环境影响下发展而来的考虑库存成本与各级企业利益协调的库存-选址区位模型。     

高铁施工材料物流中心选址研究

针对京沪线施工材料供应过程中的实际情况,以钢轨为例,分析其物流模式,引入了0-1整数规划,建立了中转站的选址模型。在建模时,考虑到了需求连续问题,用离散的可以确定位置的施工点的需求来近似连续需求,从而将连续需求问题离散化,最后用MATLAB软件对问题进行求解。     

A Hybrid model for locating new emergency facilities to improve the coverage of the road crashes

We propose an emergency facility-locating model aimed at increasing the coverage of emergency demand throughout the city. The proposed model takes into account the status and location of the emergency facilities in the network and identifies locations suitable for the construction of new facilities. Here, Data Envelopment Analysis (DEA) and Maximum Coverage Location Problem (MCLP) have been combined in a single model. To do so, design problem and evaluation problem are considered concurrently to maximize the efficiency of services provided by emergency facilities across the city in response to the demand. Moreover, the total emergency demand in each district was considered in relation to the population density, the fatal, injurious, and property damage only (PDO) crashes. The coverage area of each emergency facility was assumed to be proportional to the average ambulance speed in the surrounding road network during rush hours. The available budget was included in the model to let the model function under various fiscal conditions. Model input variables consisted of average number of mortalities, injuries and PDO crashes as well as the population density of each urban district. The output variables of the model included the coverage share of proposed emergency centers and hospitals equipped with ambulances. The model was tested on the network of Tehran (Iran). It is recommended to add the location of some emergency centers and hospitals to the network. Moreover, the results showed that ten urban districts had efficiency problem in provision of emergency services.     

零售连锁企业配送中心选址问题研究

在分析配送中心选址的一般方法的基础上,提出了适合零售连锁企业配送中心选址的两阶段选址方法。其中第一阶段为定性分析,分析零售连锁企业配送中心选址的影响因素,根据主要因素建立指标体系进行备选地的初步筛选;第二阶段为定量分析,利用节约法精选零售连锁企业配送中心位置。最后给出一个实例,说明该选址方法的有效性。     

Improving accessibility to rural health services: The maximal covering network improvement problem

Accessibility to health facilities is a critical factor in effective health treatment for people in rural areas of lesser-developed countries. In many areas accessibility is diminished by the lack of all-weather roads, making access subject to weather conditions. Location-allocation models have been used to prescribe optimal configurations of health facilities in order to maximize accessibility, but these models are based on the assumption that the underlying transport network is static and always available. Essentially, past work has ignored the potential impacts of improvements to the transport system in modeling access. In this paper we propose a model that treats the opposite side of the location/transport equation; that is, a model that treats existing facility locations as fixed and improves health service accessibility by upgrading links of the transport network to all-weather roads. This new model, called the Maximal Covering Network Improvement Problem (MC-NIP) is formulated as an integer-linear programming problem. An application of the MC-NIP model to the Suhum District of Ghana is presented, which shows that even a modest level of road improvement can lead to substantial increases in all-season access to health service.