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1.
船舶交通管理系统(Vessel Traffic Service, VTS)是我国海事主管机构进行水上安全监管的主要设备,而雷达站作为系统重要组成部分其位置选择对于整个系统安全保障效率有重要影响。针对当前VTS雷达站选址模型较少考虑选址过程中存在的山林等障碍物遮挡以及雷达无线电波传播存在衰减的问题,在考虑单个雷达失效需要备择覆盖的情况下基于集合覆盖思想提出了VTS雷达站多目标选址模型并设计算法求解及验证,然后对最大覆盖半径进行敏感性分析及讨论,结果表明最终方案能够实现选址优化并满足相关约束,为VTS雷达站在实际环境下的选址提供解决思路。  相似文献   

2.
垃圾填埋场选址问题的模糊数学模型研究   总被引:3,自引:0,他引:3  
为有助于在环境和经济框架内评价垃圾填埋场选址决策,本文建立了关于该问题的多目标模型,模型中既考虑了安置和运营设施需要的固定成本和可变成本,也考虑了居民区承受的风险,以及各居民区承担风险的公平性。并进一步讨论了用模糊方法处理的一般多目标规划模型的模糊最优解与有效解及弱有效解之间的关系。最后使用两种模糊目标规划方法求解数值例子以分析所建模型的适用性,结果表明,加权模糊方法可以为决策者提供更接近期望值的满意方案。  相似文献   

3.
为进行卫星城镇WSW中转站优化选址,本文结合城镇中转站选址经济、社会、环境负效应等相关影响因素细化分析,确定了城镇中转设施分步优化模型方法。该方法结合规范约束距离改进LSCP模型,于待选点中确定一次覆盖所有收集点的设施备选组合,而后应用综合考虑了建设运营成本、负效应、回收效率的多目标整数规划模型最终确定中转站位置、收纳量与服务分配方案。通过实例分析,验证了本文方法实用性与合理性。  相似文献   

4.
设施网络可能面临各种失灵风险,而设施选址属于战略决策问题,短期内难以改变,因而在选址设计时需要充分考虑设施的非完全可靠性。本文针对无容量限制的可靠性固定费用选址问题进行扩展,进一步考虑设施的容量约束,基于非线性混合整数规划方法建立了一个有容量限制的可靠性固定费用选址问题优化模型。针对该模型的特点,应用线性化技术进行模型转化,并设计了一种拉格朗日松弛算法予以求解。通过多组算例分析,验证了算法的性能。算例分析结果表明设施失灵风险和设施容量对于选址决策有显著影响,因而在实际的选址决策过程中有必要充分考虑设施的失灵风险及容量约束。  相似文献   

5.
农业水保措施的配置要考虑其生态效益和经济效益.不同水保措施组合方案有其相应的生态和经济效益,如何配置使综合效益最佳是一个最优化问题.分析了农业水保措施配置最优化需要考虑的两个目标,并将其公式化,建立了水保措施配置优化模型,并应用NSGA-II多目标遗传算法求解该模型.最后,以甘肃天水市罗玉沟流域的水保措施配置为例,进行了初步应用.结果表明,采用NSGA-II算法在水保措施配置优化模型求解时,计算效率较高,优化结果稳定,具有一定的应用价值.  相似文献   

6.
王珂  张玲珍  周建 《运筹与管理》2022,31(10):33-39
针对不确定环境下具有不同供应合约的供应商选择与订单分配问题,本文构建了基于风险-均值分析的模糊两阶段多周期集成优化模型。与传统的该问题研究并未充分考虑供应商选择与订单分配两阶段决策的交互影响不同,在该模型中,第一阶段供应商选择的评价目标依赖于后期实际运营中的订单分配决策;并考虑未来需求和实际运营成本的不确定性,引入在险价值和期望值两种决策准则对供应商选择方案的绩效进行评价。提出了该模型的分析求解方法,在险价值得以精确评估,期望值被控制在确定的误差范围内,并可以达到足够的精度要求。  相似文献   

7.
针对应急医疗设施的特点,提出分层递进式选址方法,对应急医疗设施进行合理选址。首先,通过熵权法对选址所需要考虑的因素进行权重计算,并进行初步选址;其次,考虑设施点的服务容量、重大公共卫生事件下轻重症患者的治疗与转移的实际情况,建立双层级整数规划模型;再次,根据模型的具体特点,设计改进的免疫优化算法对其进行求解;最后,以湖北省孝感市针对突发公共卫生事件的应急医疗设施选址问题为案例进行分析,给出相应的合理选址方案,验证了模型与算法的可行性。  相似文献   

8.
为提升应急设施的服务质量和抵御中断风险的能力,研究应急设施最大覆盖选址-分配决策问题。扩展无容量限制的固定费用的可靠性选址决策模型,建立考虑共享不确定因素的应急设施最大覆盖选址优化模型,通过在目标和约束中引入budget不确定集刻画共享不确定因素,基于Bertsimas和Sim鲁棒优化方法建立混合整数规划模型,并将非线性问题转化为易于求解的鲁棒等价模型,利用带混沌搜索策略的改进灰狼优化算法求解模型,并对不确定鲁棒水平和中断概率进行敏感性分析。最后通过案例及数据仿真结果的对比分析,验证了模型的合理性和有效性,并给出最优的选址分配布局。  相似文献   

9.
为提高应急设施运行的可靠性和抵御中断风险的能力, 研究中断情境下的应急设施选址-分配决策问题。扩展传统无容量限制的固定费用选址模型, 从抵御设施中断的视角和提高服务质量的视角建立选址布局网络的双目标优化模型, 以应急设施的建立成本和抵御设施中断的加固成本最小为目标, 以最大化覆盖服务质量水平为目标, 在加固预算有限及最大最小容量限制约束下, 构建中断情境下应急设施的可靠性选址决策优化模型。针对所构建模型的特性利用非支配排序多目标遗传算法(NSGA-Ⅱ)求解该模型, 得到多目标的Pareto前沿解集。以不同的算例分析和验证模型和算法的可行性。在获得Pareto前沿的同时对不同中断概率进行灵敏度分析, 给出Pareto最优解集的分布及应急设施选址布局网络的拓扑结构。  相似文献   

10.
警车配置及巡逻方案研究   总被引:1,自引:0,他引:1  
以警车的配置与巡逻方案为研究对象,建立了一套警车巡逻模型,并提出巡逻效果显著度及隐藏性的评价标准,分别针对警车初始位置配置与巡逻方案的制定,提出警车配置优化选址的贪婪算法与基于多Agent的警车巡逻方案设计方法,给出了不同情景下的配置及巡逻方案:①在只考虑警车选址配置的情况下,配置19辆警车可以使全市路网警车覆盖率达到92.8%;②在顾及巡逻效果显著性与隐藏性的情况下,配置25辆警车使全市路网在整个巡逻过程中平均警车覆盖率达到90.9%;③在配置10辆警车的情况下,使得全市路网在整个巡逻过程中平均警车覆盖率达到61.5%.  相似文献   

11.
Location of fire stations is an important factor in its fire protection capability. This paper aims to determine the optimal location of fire station facilities. The proposed method is the combination of a fuzzy multi-objective programming and a genetic algorithm. The original fuzzy multiple objectives are appropriately converted to a single unified ‘min–max’ goal, which makes it easy to apply a genetic algorithm for the problem solving. Compared with the existing methods of fire station location our approach has three distinguish features: (1) considering fuzzy nature of a decision maker (DM) in the location optimization model; (2) fully considering the demands for the facilities from the areas with various fire risk categories; (3) being more understandable and practical to DM. The case study was based on the data collected from the Derbyshire fire and rescue service and used to illustrate the application of the method for the optimization of fire station locations.  相似文献   

12.
This paper deals with the mathematical modeling and optimization of a code division multiple access (CDMA) cellular system configuration that seeks the optimal location, power, and antenna height of each base station in a service area, in order to optimize call quality, service coverage and total cost of system configuration. The factors affecting optimum selection are the non-uniform spatial demand in the service area, the propagation environment, the interference among users and among base stations, and other factors intrinsic to CDMA technology. The simulated annealing method supplemented by a demand allocation algorithm is implemented in a software package to solve this complex multiobjective nonlinear optimization problem. This research shows that simulated annealing is a viable method for obtaining good quality solutions to the wireless system configuration problem. A realistic case study dealing with the design of a cellular system configuration for the city of Cambridge, MA, and its surroundings, is developed to illustrate the modeling concept and the steps of the algorithm. Sensitivity analysis is performed to further analyze the configuration decision.  相似文献   

13.
在对国内外咽喉道岔通过能力计算方法比较与分析基础上 ,论文提出了车站咽喉通过能力可视化计算集成系统的系统结构和功能设计 ,应用图论和网络优化技术对车站咽喉布置、咽喉及车站作业过程进行抽象建模 ,建立了咽喉作业占用安排网络优化和咽喉作业能力的复合递阶决策模型 .该研究综合运用上述模型、算法、计算机信息处理技术和图形技术 ,可视化模拟咽喉作业情况 ,实现了核心基础数据计算机模拟采集、作业优化安排和最大可实现能力的查定及优化 ,并将结果以图形方式输出 .通过实例验证表明 ,计算结果合理可信 ,可用于车站咽喉能力的评价检验 .  相似文献   

14.
通过引入一个无量纲参数,将重量和雷达吸波性能两个优化目标结合于同一个目标函数中,提出了针对含有多孔材料芯层的夹芯型雷达吸波结构(RASS)的一种多目标优化设计方法.优化模型为承受均布载荷的悬臂夹芯板,考虑4种不同形式的芯层.由传输矩阵法和周期矩量法计算出镜面反射率的平均值,作为表征吸波性能的指标;而面板屈服、芯层剪切破坏和面板起皱则作为优化设计中的力学性能约束.优化结果表明,以填充超轻质海绵体的复合材料二维点阵为芯层的夹芯结构,比含有多孔泡沫或六角蜂窝芯层的夹芯结构更适合作为轻质夹芯型雷达吸波结构.Kagome二维点阵则表现出优于正方二维点阵的吸波性能.  相似文献   

15.
Considering the uncertainty of the macroeconomic environment, the robust optimization method is studied for constructing and designing the automotive supply chain network, and based on the definition of robust solution a robust optimization model is built for integrated supply chain network design that consists of supplier selection problem and facility location–distribution problem. The tabu search algorithm is proposed for supply chain node configuration, analyzing the influence of the level of uncertainty on robust results, and by comparing the performance of supply chain network design through the stochastic programming model and robustness optimize model, on this basis, determining the rational layout of supply chain network under macroeconomic fluctuations. At last the contrastive test result validates that the performance of tabu search algorithm is outstanding on convergence and computational time. Meanwhile it is indicated that the robust optimization model can reduce investment risks effectively when it is applied to supply chain network design.  相似文献   

16.
Simulation optimization provides a structured approach to system design and configuration when analytical expressions for input/output relationships are unavailable. This research focuses on the development of a new simulation optimization technique applicable to systems having multiple performance measures. The aim of this research is to incorporate a simulation end user’s preference towards risk and uncertainty into the search process for the best decision alternative. Automation of the optimization procedure is a necessity. Therefore, this paper proposes a simulation optimization method that involves a preference model, specifically adapted for decision making with simulation models.  相似文献   

17.
The concern about environmental impact of business activities has spurred an interest in designing environmentally conscious supply chains. This paper proposes a multi-objective fuzzy mathematical programming model for designing an environmental supply chain under inherent uncertainty of input data in such problem. The proposed model is able to consider the minimization of multiple environmental impacts beside the traditional cost minimization objective to make a fair balance between them. A life cycle assessment-based (LCA-based) method is applied to assess and quantify the environmental impact of different options for supply chain network configuration. Also, to solve the proposed multi-objective fuzzy optimization model, an interactive fuzzy solution approach is developed. A real industrial case is used to demonstrate the significance and applicability of the developed fuzzy optimization model as well as the usefulness of the proposed solution approach.  相似文献   

18.
《Optimization》2012,61(11):1761-1779
In this article, we study reward–risk ratio models under partially known message of random variables, which is called robust (worst-case) performance ratio problem. Based on the positive homogenous and concave/convex measures of reward and risk, respectively, the new robust ratio model is reduced equivalently to convex optimization problems with a min–max optimization framework. Under some specially partial distribution situation, the convex optimization problem is converted into simple framework involving the expectation reward measure and conditional value-at-risk measure. Compared with the existing reward–risk portfolio research, the proposed ratio model has two characteristics. First, the addressed problem combines with two different aspects. One is to consider an incomplete information case in real-life uncertainty. The other is to focus on the performance ratio optimization problem, which can realize the best balance between the reward and risk. Second, the complicated optimization model is transferred into a simple convex optimization problem by the optimal dual theorem. This indeed improves the usability of models. The generation asset allocation in power systems is presented to validate the new models.  相似文献   

19.
朱江洪  李延来  王睿 《运筹与管理》2018,27(12):147-157
针对考虑群体评价一致性和专家心理感知行为影响的失效模式及影响分析风险评估问题,提出了基于前景理论和偏好序结构排序法(PROMETHEE)的风险评估方法。首先,专家团队采用语言变量表征风险因子评价信息,利用直觉模糊熵确定风险因子客观权重;其次,采用灰关联度刻画专家评价与群体评价的一致性,以最大化关联度和极大熵准则构建专家权重优化模型;然后,集成风险因子和专家的主客观权重,获得风险因子及专家的综合权重;再次,运用直觉模糊加权平均算子集结专家评价信息,进而借助前景理论构建反应专家心理感知的前景矩阵;最后,基于PROMETHEE方法确定失效模式风险排序,并利用液晶显示器的案例验证了所提方法的有效性和可行性。  相似文献   

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