区际救援物资中转运输网点的定位—配给问题研究*

为增强大规模区际救援物资联动调运的效率,建立了救援物资中转网点的定位—配给模型,并设计了一种运用矩阵编码的遗传算法。在算法流程设计中,为提高标准遗传算法求解非线性运输问题的寻优速度和寻优效能,参照费用矩阵标杆的寻优导向信息来指导种群中每个个体局部的精细搜索空间。最后通过算例分析验证了该模型和算法的有效性。     

区际救援物资中转调度的多目标优化问题研究

针对大规模、远距离和多品种的区际救援物资联动调运问题,以区际救援物资送达受灾城市总时间最短和总成本最小为目标,建立了一个区际救援物资中转调度的多目标优化模型,并设计了一种多目标协进化遗传算法。算例分析验证了该算法能够较好地获取问题的Pareto最优解。     

城市应急救援物资运输分配模型的构建与求解

应急物资运输问题属于多目标规划问题,它集成了多货物、多起点、多种运输方式、没有固定起止点等特殊性质的物流运输问题。本文使用多目标规划方法构造了一个在实际情况下使用的救援物资运输分配模型,该模型具有三个目标:应急物资运输的总成本最低、运输时间最短,实现最大满意度和公平性,该模型的前两个目标是追求效率,而第三个目标是追求公...     

面向应急物资调度的一种灰色规划模型*

为了科学合理地进行救援物资的调度,考虑在满足处置突发应急事件需求的同时,所耗物资降到最低限度,并且从总体上最大限度地降低处置突发应急事件物资运输调度的费用。在现有研究成果的基础上引入了灰色理论的知识,建立了应急开始时间最短、出救点个数最少以及需求约束偏爱度最大的多目标灰色规划模型,并通过算例用遗传算法实现该问题的求解,通过测试优选了种群数目、交叉率和变异率三种控制参数值以提高算法性能。实验所得的数据值越大,说明调度方案越好。实验结果表明,同限期最大量算法相比,在所有物资供应点提供的物资总量一定的情况下,应急地点所需的物资数量较少时,遗传算法针对该模型的求解体现更强的优化能力,其所得适应值更高,遗传算法对于求解应急物资调度灰色规划问题的适应性较强。     

区域性应急物资储备库选址－配给模型与算法

为整合区域性应急物资储备资源,加强储备物资的协同管理,研究了区域性应急物资储备库的多点选址-配给问题。建立了以储备库建设成本与变动成本、物资运输成本之和最小化,以及物资运输总时间最小化的区域性应急物资储备库选址-配给多目标优化模型。鉴于多品种、多目标选址-配给问题的特点,设计了一种改进的多目标遗传算法,并用MATLAB编程实现模型的求解。在算法流程设计中,对于高维稀疏矩阵编码且具有强约束限制的选址-配给问题,初始化过程中采取搜索空间限定法来规避违约,并设计了定位变异算子以此生成子代。算例分析结果表明该算法性能较好,可以有效求解多点设施选址-配给问题。     

震后随机动态LRP多目标优化模型及算法*

为了在地震灾区快速配送救灾物资,建立了一个多产品多运输方式的随机动态应急配送中心定位—运输路线安排问题的多目标优化模型,据此得出不同阶段应急配送中心的定位以及救援物资运输路线安排决策方案。根据该模型的特点,提出一种基于动态规划和权重系数变换法的改进遗传算法,并运用罚函数法处理模型中的约束条件。算例分析表明了该模型和算法的有效性,能为应急管理部门提供辅助决策支持。     

面向多层级出救点的应急物资调度模型研究*

针对我国应急救灾物资储备库系统的物资调度和运输的组织特点,依据受灾点的多层级储备库优先级模型,建立了针对多出救点、多受灾点的应急物资调度模型,实现应急开始时间最早、出救点数目最少的多目标优化,设计了模型求解方法,并给出实例验证了此模型的有效性和合理性。该模型已成功运用在国家应急救灾物资调度系统设计和玉树地震模拟物资调度方案的制定中。     

多禁止时间窗约束的路径恢复问题研究

突发灾难的应急物资的配送有时受多禁止时间约束，为此，针对多禁止时间窗约束的应急物资运输路径优化问题，考虑多禁止时间窗的约束，建立了以总配送时间最小为目标、多禁止时间窗约束的应急物资运输路径优化模型。鉴于该模型为混合整数规划模型，采用GUROBI求解，并与建立的对应的多时间窗约束的路径优化模型对比。最后通过算例分析验证了该模型的高效性和算法的有效性。结果表明，多禁止时间窗约束的应急物资运输路径优化模型求解效率更高；此外评估救灾点对配送时间的影响以及分析多禁止时间窗对应急物资配送规划的影响，结果表明部分救灾点显著影响总配送时间，禁止时间窗的开始时间以及宽度影响总配送路线、时间以及到达各救灾点的时间，因此考虑时间约束特点可为应急物资运输决策提供实用价值。     

多受灾点应急救援车辆调度的优化遗传算法

在多个地区发生灾害后,迫切需要及时救援和物资的快速运输,从仓库调拨物资到受灾点,交通网络规模较大,运输货物类型多样,并且要满足各个受灾点的资源需求、实时路况、运抵时限要求等多个目标约束条件,车辆调度具有较大难度.为解决多重约束带来的困难,根据遗传算法的生物进化理论和群体遗传学机制,建立了车辆应急运输的多目标优化问题模型,设计合适的序列编码方式表示车辆行进路线及运输货物类型;建立了新的优化遗传算法,从编码方式的设计、适应度函数、选择、交叉和变异操作机制的设计三个方面做了创新改进,主动保持优良基因,根据阶段进展调节交叉和变异概率,有效提高好的新模式的产生几率,较好地克服了已有方法的早熟局部收敛所导致的结果偏差较大的不足.多个仿真实验结果表明,优化遗传算法比已有算法在满足送达时限以及送达时间的总长度等方面均有较大提高,对于复杂的调度任务,在保证运抵时限的前提下,可占用更少的车辆,花费更少的行进时间完成物资运输,从而满足多受灾点对物资的实时性需求.     

基于蚁群算法的高原地区车辆运输路径优化问题

以高原地区救援物资运输为背景,从提升部队精细化保障能力落脚点出发,针对当前高原地区后勤运输存在的不足,利用优化蚁群算法对高原地区后勤保障中的运输线路选择问题进行深入研究。建立高原地区救援物资运输按时供给函数模型（VRPTW）,并通过运输案例验证模型和算法的可行性和有效性。最后运用项目管理软件（Project 2013）对运输方案的日程安排和资源分配进行统筹和管理,实现运输时间最短和运输效益最高的双重目标。     

Robust and fuzzy goal programming optimization approaches for a novel multi-objective hub location-allocation problem: A supply chain overview

In this paper, a novel multi-objective mathematical model is developed to solve a capacitated single-allocation hub location problem with a supply chain overview. Three mathematical models with various objective functions are developed. The objective functions are to minimize: (a) total transportation and installation costs, (b) weighted sum of service times in the hubs to produce and transfer commodities and the tardiness and earliness times of the flows including raw materials and finished goods, and (c) total greenhouse gas emitted by transportation modes and plants located in the hubs. To come closer to reality, some of the parameters of the proposed mathematical model are regarded as uncertain parameters, and a robust approach is used to solve the given problem. Furthermore, two methods, namely fuzzy multi-objective goal programming (FMOGP) and the Torabi and Hassini's (TH) method are used to solve the multi-objective mathematical model. Finally, the concluding part presents the comparison of the obtained results.     

三层物流网络选址-路径优化及混合启发式算法研究*

为同时解决转运、分配、选址和车辆路径问题,在考虑车辆载重和行驶距离约束,配送中心处理能力约束的基础上,构建了一个多产品三层物流网络选址-路径模型,以总成本最小为目标,提出一种基于贪婪随机自适应搜索算法和里程节约算法的混合启发式算法,给出了该算法的步骤和伪代码。实验结果表明该算法具有可行性,并且与其他算法比较而言,算法具有高效性。     

An interactive possibilistic programming approach for a multi-objective hub location problem: Economic and environmental design

This paper presents a new multi-objective mathematical model for a multi-modal hub location problem under a possibilistic-stochastic uncertainty. The presented model aims to minimize the total transportation and traffic noise pollution costs. Furthermore, it aims to minimize the maximum transportation time between origin-destination nodes to ensure a high probability of meeting the service guarantee. In order to cope with the uncertainties and the multi-objective model, we propose a two-phase approach, including fuzzy interactive multi-objective programming approach and an efficient method based on the Me measure. Due to the NP-hardness of the presented model, two meta-heuristic algorithms, namely hybrid differential evolution and hybrid imperialist competitive algorithm, are developed. Furthermore, a number of sensitivity analyses are provided to demonstrate the effectiveness of the presented model. Finally, the foregoing meta-heuristics are compared together through different comparison metrics.     

Transshipment and safety stock under stochastic supply interruption in a production system

We consider a two-echelon system with one source supplying two locations with the same product. The random occurrence of interruptions at the source where downtime is also stochastic can result in stockouts at the two receiving locations. Our model studies the benefit of allowing each location to carry a safety stock where holding costs can be different at each location. The objective is to reduce overall cost at both locations. In some cases it is optimal to allow for a transshipment of inventory from the safety stock of one location to the other. We jointly solve for the optimal safety stock at each location and the optimal amount to be transshipped from a location to the other. We show that by conditioning on the transshipment direction the total cost becomes convex as a function of the safety stock levels at the receiving locations and the amount to be transshipped from a location to the other. Numerical examples are presented for different system cost parameters and probability distributions.     

Spatial Analysis of Single Allocation Hub Location Problems

Hubs are special facilities that serve as switching, transshipment and sorting nodes in many-to-many distribution systems. Flow is consolidated at hubs to exploit economies of scale and to reduce transportation costs between hubs. In this article, we first identify general features of optimal hub locations for single allocation hub location problems based on only the fundamental problem data (demand for travel and spatial locations). We then exploit this knowledge to develop a straightforward heuristic methodology based on spatial proximity of nodes, dispersion and measures of node importance to delineate subsets of nodes likely to contain optimal hubs. We then develop constraints for these subsets for use in mathematical programming formulations to solve hub location problems. Our methodology can also help narrow an organization’s focus to concentrate on more detailed and qualitative analyses of promising potential hub locations. Results document the value of including both demand magnitude and centrality in measuring node importance and the relevant tradeoffs in solution quality and time.     

震后初期应急物资配送LRP中的干扰管理研究

研究震后初期应急物资配送定位-路径问题（LRP）中的干扰事件实时决策方法,综合考虑灾区路网损毁情况、需求点的模糊需求量与时间窗限制、多方式配送等因素,以应急物资总配送时间最短构建了震后应急物流LRP的优化模型,并结合行为科学中对人的行为感知的研究方法从灾区需求点、应急决策部门、应急物流执行者三个方面分析干扰事件对应急物流系统的扰动,在此基础上以系统扰动最小为目标构建一个字典序的干扰管理模型。最后,根据模型特点设计干扰事件处理策略与混合蚁群算法予以求解。算例结果表明,该方法比全局重优化方法和局部重优化方法更加合理有效。     

带有横向调度的维修备件选址库存路径问题研究

存储点的合理选址、库存的合理控制及运输配送的有效决策是支撑维修备件物流系统的重要内容。通过分析基于横向调度的维修备件物流系统,建立了基于横向调度的维修备件库存选址问题的数学模型,设计了隐枚举法和遗传算法相结合的启发式算法,通过仿真算例验证了方法的可行性和模型的先进性。通过分析得出,在考虑横向调度的情况下,物流系统内总体安全库存和最大虚拟库存总体水平会降低,同时实现对客户的服务承诺也会降低。