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1.
探究传统关键链方法在实践应用中出现的问题并提出改进措施。首先剖析出三个方面的不足:第一,基准调度计划不唯一;第二,非关键链的识别方式导致输入缓冲失效;第三,对插入输入缓冲时引起的二次资源冲突问题,现有的解决方法与缓冲的本质作用相背离。据此,基于鲁棒性调度优化的思想,采用理论分析和案例说明相结合,针对三个方面分别提出了相应的解决方案,形成鲁棒性视角下的关键链项目调度新方法。研究结论对于将关键链方法科学地应用于项目管理实践提供了理论指导。  相似文献   

2.
通过对多项目管理瓶颈的分析,结合关键链方法,设置了瓶颈缓冲,建立了基于关键链方法的多项目管理,为多项目管理提供了一种新的管理方法.将基于关键链方法的多项目管理方法应用于并行多项目共享人力资源冲突管理,建立了基于遗传算法的多项目共享人力资源均衡模型,为缓解多项目共享人力资源供求矛盾提供了一种具体的量化管理方法,并进行了算例分析,证明了模型的有效性、实用性.  相似文献   

3.
张俊光  万丹 《运筹与管理》2021,30(2):218-224
为了提高关键链多项目缓冲管理的效率,首次提出了一种基于多项目双重风险共担的鼓缓冲设置方法。新方法从系统角度分析了多项目不同层级的风险共担作用,以同时落在在子项目关键链和多项目系统关键链上的系统关键活动工期占比为切入点对缓冲进行分层管理,抽取部分项目缓冲集中到系统层面,同时综合考虑风险独立因子以及鼓活动有效产出影响指数对鼓缓冲进行了定量设置。仿真结果表明,本文方法在多项目按时完工率、项目缓冲平均消耗率、系统关键链上鼓活动平均延误百分比、多项目系统总工期和成本这几个绩效方面的表现更优,提高了多项目系统的风险应对能力。  相似文献   

4.
针对基于多代理系统求解分布式多项目调度问题的不足, 开发了一种适应性的遗传算法ccm_GA。ccm_GA的独特性体现为两点:第一, 修正的串行调度过程分两个阶段分别消除全局资源和本地资源冲突; 第二, 在满足两类资源约束的调度方案中, 识别出关键链并改变关键活动在活动序列编码中的位置以增加解的多样性从而提高搜索效率。设计并实施大规模数值实验测试算法性能, 与现有文献中的六种算法作对比, 结果表明:ccm_GA在50%的算例集上获得的测试指标都好于六种算法, 且对于资源约束越紧的算例集, ccm_GA的求解效果越好。  相似文献   

5.
针对实践中分布式多项目的活动往往具有多种执行模式,提出多模式分布式资源约束多项目调度问题。在项目动态到达环境下,考虑活动不同的执行模式,以工期最短和多项目延期成本最小为目标分别构建局部单项目调度模型和全局多项目决策模型,采用改进变邻域搜索算法求解初始局部调度计划,并设计基于模式调整的全局协商调度算法求解全局决策模型,通过双层算法实现分布式多项目调度中局部单项目调度与全局多项目调度系统性协调,减少项目中断和多项目延期成本。基于构建的多模式测试集进行的多项目数值实验表明:本文设计的双层算法可有效求解多模式分布式多项目调度问题,并且对不同规模问题求解具有良好的适应性。  相似文献   

6.
针对云计算资源调度模型具有复杂性和不确定性,导致资源分配合理性较差,存在资源浪费的问题,提出一种改进的共生优化算法对云计算资源调度模型进行优化.针对共生算法存在局部搜索能力较差以及在迭代后期易早熟陷入局部最优的问题,通过镜像初始化以及牛顿局部增强策略进行改进,并进行数值仿真实验.最后以改进后的共生优化算法对云计算资源调度模型进行优化求解,实验结果表明,改进后的共生优化算法有效提降低了云计算所需时间和能耗花费,提高了资源利用率.  相似文献   

7.
研究多技能人力资源在项目活动上的指派与调度问题.首先,从问题特点出发,把原始问题分解为指派问题子模型和调度问题子模型.然后,对项目活动间的重叠关系进行识别,将其转化为对指派问题的有效约束,构建数学规划与约束规划相结合的混合算法对问题求解,并采用CPLEX编程实现.研究表明,算法可有效缩减指派问题的可行域,快速地找到问题的近优解,从而提高多技能人力资源的使用效率,是求解项目多技能人力资源指派与调度问题的一个有效方法.  相似文献   

8.
调度研究的问题是将稀缺资源分配给在一定时间内的不同任务,它是一个决策过程,其目的是优化一个或多个目标。对实际问题的优化调度可以帮助企业提高资源利用率,减少客户等待时间,提升竞争力,对汽车4S维修服务站的优化调度问题进行研究,剖析这一实际应用问题的调度目标、机器环境、加工特征和约束等细节,提出了优化调度模型,设计了调度算法。然后,通过实例,简要分析了模型及算法的可行性.  相似文献   

9.
项目调度中的时间和费用是两个重要的指标,而在不确定环境下进度计划的鲁棒性则是保证项目平稳实施的关键。本文研究不确定环境下的多目标项目调度优化问题,以优化项目的工期、鲁棒值和成本为目标安排各活动的开始时间。基于此,作者构建多目标项目调度优化模型,将模型分解为三个子模型分析目标间的权衡关系,然后设计非劣排序遗传算法进行求解,应用精英保留策略和基于子模型权衡关系的优化策略优化算法,进行算法测试和算例参数敏感性分析。最后,应用上述方法研究一个项目实例,计算得到非劣解集,实例的敏感性分析结果进一步验证了三个目标间的权衡关系,据此提出资源的有效利用策略。本文的研究可以为多目标项目调度制定进度计划提供定量化决策支持。  相似文献   

10.
从项目双方的视角出发,研究融资能力约束下的Max-npv项目调度问题。首先进行问题界定,构建由两个子模型构成的多模式Max-npv项目调度优化模型。随后,鉴于问题的强NP-hard属性,设计针对两个子模型迭代循环求解的禁忌搜索启发式算法,得到项目双方都满意的解。最后用一个实际案例对研究进行验证说明,并分析关键参数对合同双方收益的影响,结果表明:与实际进度安排相比,满意进度安排下合同双方的收益均有显著的提升;承包商和业主的融资能力、项目截止日期、承包商收益底线、折现率及支付比例均会对双方的收益产生重要影响。  相似文献   

11.
现有的分布式资源约束多项目调度问题研究中,假定全局资源限量在多项目工期内不可突破且多以工期为优化目标。针对此问题,考虑全局资源可从外部获取,以净现值为目标,构建带有全局资源柔性约束的分布式多项目调度问题的整数规划模型并设计有效的求解算法。首先,界定问题并确定项目现金流的计算方法;然后,针对求解问题的NP-hard属性,设计了遗传-模拟退火混合算法(GA_SA)求解此模型。最后,通过多组数值实验,设计不同算法与GA_SA算法进行比较,并分析了关键参数对多项目净现值的影响。结果表明,GA_SA算法具有较好的求解效果;与传统的全局资源刚性约束条件相比,全局资源柔性使用状态可以显著改善分布式多项目的收益绩效。  相似文献   

12.
This paper introduces a multi-project problem environment which involves multiple projects with assigned due dates; activities that have alternative resource usage modes; a resource dedication policy that does not allow sharing of resources among projects throughout the planning horizon; and a total budget. Three issues arise when investigating this multi-project environment. First, the total budget should be distributed among different resource types to determine the general resource capacities, which correspond to the total amount for each renewable resource to be dedicated to the projects. With the general resource capacities at hand, the next issue is to determine the amounts of resources to be dedicated to the individual projects. The dedication of resources reduces the scheduling of the projects’ activities to a multi-mode resource constrained project scheduling problem (MRCPSP) for each individual project. Finally, the last issue is the efficient solution of the resulting MRCPSPs. In this paper, this multi-project environment is modeled in an integrated fashion and designated as the resource portfolio problem. A two-phase and a monolithic genetic algorithm are proposed as two solution approaches, each of which employs a new improvement move designated as the combinatorial auction for resource portfolio and the combinatorial auction for resource dedication. A computational study using test problems demonstrated the effectiveness of the solution approach proposed.  相似文献   

13.
We consider the problem of scheduling multiple projects subject to joint resource constraints. Most approaches proposed in the literature so far are based on the unrealistic assumption that resources can be transferred from one project to the other without any expense in time or cost. In order to contribute to closing this gap to reality, we generalise the multi-project scheduling problem by additionally including sequence- and resource-dependent transfer times, which represent setup activities necessary when a resource is removed from one project and reassigned to another (or from one job to another within the same project). In this paper, we define the modified resource constrained multi-project scheduling problem with transfer times (called RCMPSPTT), which aims at minimising the multi-project duration for the single-project approach or the mean project duration for the multi-project approach. We formulate both perspectives as an integer linear program, propose priority rule based solution procedures and present results of comprehensive computational experiments. Provided that the combination of scheduling scheme and priority rules is chosen appropriately, the procedures obtain good results. In particular, resource oriented priority rules are identified to be successful.  相似文献   

14.
Scheduling for the Earth observation satellites (EOSs) imaging mission is a complicated combinatorial optimization problem, especially for the agile EOSs (AEOSs). The increasing observation requirements and orbiting satellites have exacerbated the scheduling complexity in recent years. In this paper, the single agile satellite, redundant observation targets scheduling problem is studied. We introduce the theory of complex networks and find similarities between AEOS redundant targets scheduling problem and the node centrality ranking problem. Then we model this problem as a complex network, regarding each node as a possible observation opportunity, and define two factors, node importance factor and target importance factor, to describe the node/target importance. Based on the two factors, we propose a fast approximate scheduling algorithm (FASA) to obtain the effective scheduling results. Simulation results indicate the FASA is quite efficient and with broad suitability. Our work is helpful in the EOSs and AEOSs scheduling problems by using complex network knowledge.  相似文献   

15.
主要研究工程建设企业多项目人力资源优化配置问题。以项目经理这一关键性人力资源为对象,构建了基于胜任力模型的工程建设企业项目经理能力定级指标体系,给出了具体的能级评价方法,解决了待分配人员的定级和排序问题;在项目优先级和人员能级界定的基础上,以多项目工期均衡和人工总成本最低为目标建立了两阶段优化模型,给出了基于贪婪算法和线性规划的模型求解算法,设计了MATLAB程序对模型进行求解;最后通过实例验证了优化配置模型和求解算法的有效性。  相似文献   

16.
在供应链环境下研究跨组织的资源受限项目调度问题,从项目调度整体效用最大化角度,考虑工期、成本和资源均衡对项目调度的影响。构建并剖析供应链环境下跨组织的资源受限项目调度模型,利用正态云模型中云滴的随机性与稳定性的特征改进遗传算法中交叉算子与变异算子的设置方式,并对模型进行数据模拟和算例分析。结果表明,以工期-成本-资源均衡为优化目标,不仅可实现供应链环境下跨组织的资源受限项目调度的效用最大化,且可缩短项目工期、降低成本并提高资源的利用率。  相似文献   

17.
We consider a non-preemptive, zero time lag multi-project scheduling problem with multiple modes and limited renewable and nonrenewable resources. A two-stage decomposition approach is adopted to formulate the problem as a hierarchy of 0-1 mathematical programming models. In stage one; each project is reduced to a macro-activity with macro-modes. The macro-activities are combined into a single macro-activity network over which the macro-activity scheduling problem (MP) is defined, where the objective is the maximization of the net present value with positive cash flows and the renewable resource requirements are time-dependent. An exact solution procedure and a genetic algorithm (GA) approach are proposed for solving the MP. A GA is also employed to generate an initial solution for the exact solution procedure. The first stage terminates with a post-processing procedure to distribute the remaining resource capacities. Using the start times and the resource profiles obtained in stage one, each project is scheduled in stage two for minimum makespan. Three new test problem sets are generated with 81, 84 and 27 problems each, and three different configurations of solution procedures are tested.  相似文献   

18.
We consider a multi-project scheduling problem, where each project is composed of a set of activities, with precedence relations, requiring specific amounts of local and shared (among projects) resources. The aim is to complete all the project activities, satisfying precedence and resource constraints, and minimizing each project schedule length. The decision making process is supposed to be decentralized, with as many local decision makers as the projects. A multi-agent system model, and an iterative combinatorial auction mechanism for the agent coordination are proposed. We provide a dynamic programming formulation for the combinatorial auction problem, and heuristic algorithms for both the combinatorial auction and the bidding process. An experimental analysis on the whole multi-agent system model is discussed.  相似文献   

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