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1.
In a multi-project industrial R & D organization the selection of projects with potentially good payoffs has to be fitted in with the planning of on-going projects as they compete for the same expert staff, laboratory equipment, pilot plant rigs and other facilities and resources. A linear programming approach to this planning problem takes account of any flexibility possible in allocating resources to projects, and in their timing in finding the ‘best’ plan. This is the one which maximises the potential payoff for the whole ‘portfolio’ of projects and makes the most efficient use of the available resources. The principles of the formulation of such LP models and the interpretation of the results produced in terms of practical planning are discussed.  相似文献   

2.
实践中,企业并行实施地域上分散的多个项目时,资源在各子项目之间的转移时间是影响多项目整体进度的关键因素,同时在动态多项目环境下,新项目不断到达且到达时间不可预知使得制定多项目调度计划遭遇更大困难。本文在动态环境下对资源转移时间型分布式多项目调度问题进行建模和求解,基于多代理系统建立分布式多项目调度问题的动态模型,并将拍卖理论引入其中,设计一种基于时间窗拍卖机制的分布式多代理系统(DMAS/ATW),在动态环境和资源转移时间约束下为多项目配置全局资源。通过一个具体的分布式多项目示例详细分析DMAS/ATW算法的动态调度过程,并基于MPSPLIB中的分布式多项目算例开展数值实验。实验结果表明:无资源转移时间约束时,DMAS/ATW算法求得的平均项目延迟同比相关文献中的DMAS/RIA算法最多减少42%,平均减少26%;有资源转移时间约束时,DMAS/ATW算法对1/3算例集的求解结果优于DMAS/RIA算法在无资源转移时间约束时的结果,验证了本文DMAS/ATW算法求解效果的优异性。对算例规模和全局资源利用系数的实验分析还表明,DMAS/ATW算法对不同规模和资源约束紧张程度的算例都具有良好的适应性。  相似文献   

3.
大型建筑工程项目多类型资源的有效配置,是现阶段项目管理理论与工程管理实践面临的关键问题,特别是在考虑工艺顺序和间歇时间的工作可操作性特点,以及多资源之间反馈影响的情况下。通过整合挣值法和系统动力学理论,在分析资源可用性和工作可操作性之间因果关系的基础上,本文构建了大型建筑工程项目多资源配置的系统动力学模型。以上海市重大工程投资统计数据作为模型参数依据,模型的仿真结果表明:建筑工程项目不同类型资源其配置重要性与系统影响性存在显著差异,在制定资源配置策略时应同时考虑项目运作方式的特征与多资源之间的匹配,资源不匹配则容易导致资源配置系统失去稳态或策略失效。这为进一步研究项目管理中多资源配置提供了理论参考和实践支持。  相似文献   

4.
Capacity planning is instrumental in production planning as the variability witnessed in construction projects complicates the planner’s role in achieving a balance between weekly task load and available resources. The purpose of this article is to assess the effects of capacity planning on a project’s time and cost performance and to inform planners on the pitfalls of uninformed capacity planning. A simulation model is developed to test several project scenarios against different capacity planning methods. Cost, time and planning quality measures are developed to track project’s performance throughout the construction period. Results show that the planner’s choice of capacity planning method and the type of project both affect a project’s cost and duration. Interestingly, informed planners who are aware of a project’s characteristics are able to achieve the best balance between weekly load and capacity. They are able to reduce incurred costs wasted on idle resources without significantly affecting the construction period.  相似文献   

5.
We develop a dynamic prioritization policy to optimally allocate a scarce resource among K projects, only one of which can be worked on at a time. When the projects' delay costs differ, the problem (a “restless bandit”) has not been solved in general. We consider the policy of working on the project with the highest expected delay loss as if the other project was completely finished first (although recourse is allowed). This policy is optimal if: (1) the delay cost increases with the delay regardless of the performance state, (2) costs are not discounted (or, discounting is dominated by delay costs), (3) projects are not abandoned based on their performance state during processing at the scarce resource, and (4) there are no stochastic delays. These assumptions are often fulfilled for processing at specialized resources, such as tests or one‐off analyses.  相似文献   

6.
S-curves are widely used for planning, forecasting and control of cost, time and resources of a project. In this paper, a comparison of two S-curve models developed at the Department of Health and Social Security (DHSS) and Bradford University is carried out both from the viewpoint of predictive accuracy and ease of use. The models are validated using expenditure data for 21 recent U.K. health building projects. Methods of least squares is used to estimate the parameters of the two models. These parameters are categorized according to the total cost of the projects. Both the models are shown to be of comparable accuracy for fitting actual expenditure data. The DHSS model has a major advantage of simplicity of form and use, although the slightly greater mathematical complexity of the Keller-Singh model is off-set by the readily interpretable nature of its form and basic parameters. It is concluded that both or either of the models could be used by clients/contractors for effective planning and control of project costs.  相似文献   

7.
In recent years, there has been increasing pressure on the US federal government to reduce spending and improve the management of its technology projects. Mitigating the adverse impact of risks on the performance of these projects presents a significant challenge for its stakeholders. Our research examines this challenge in two steps. First, we identify and define a set of salient risks in federal technology projects—specifically, complexity risk and contracting risk in the planning process, and execution risk in the execution process. Next, we investigate whether higher levels of process maturity, assessed by the Capability Maturity Model Integration (CMMI) framework, mitigate the negative effect of project risks on project performance. The analysis of time‐series data collected from 82 federal technology projects across 519 quarterly time periods indicates that each of the three types of risks has a significant negative effect on project performance. This finding highlights the practical significance of managing these risks in the federal technology project context. Further, we find that increasing levels of process maturity attenuate the negative effect of project risks on the performance of federal technology projects. However, the attenuation effects are consequential only at high levels of project risks; at low levels of project risk, increasing levels of process maturity can adversely affect project performance. To demonstrate the financial implications of increasing process maturity levels in federal technology projects, we examine the magnitude of project cost savings (and overruns) across different levels of CMMI and project risks. In summary, our study contributes to the sparse literature on public sector operations by addressing the understudied context of federal technology projects, and provides a nuanced examination of the implications of process maturity in managing the risk to performance relationship in such projects.  相似文献   

8.
多项目资源管理有时需要采用一种资源专享-转移策略,该策略下可更新资源在多项目之间不共享,但在当前项目完工之后其资源可以转移至其它还未开始的项目。针对这一实际问题的理论研究非常有限。考虑活动工期的不确定性,从时差效用函数视角评价项目调度计划的鲁棒性,在考虑拖期成本-鲁棒性的多目标问题框架下,构建了一个资源专享-转移视角下的多项目资源分配(战术层)与鲁棒调度(运作层)双层决策优化模型。针对模型的NP-hard性质和多目标组合优化特征,设计了一种新的自适应大邻域搜索(adaptive large neighborhood search,ALNS)算法求解模型。该算法采用“项目-缓冲-资源-活动”列表的混合编码表示问题可行解,提出基于四类列表的destroy-repair邻域结构,设计一种超体积指标进行自适应搜索以提高算法性能。最后,为了验证ALNS算法的适用性和有效性,设计一种NSGA-II算法作为比较基准,通过大规模仿真实验对算法性能进行了对比分析,并探索工期不确定水平对多项目调度方案鲁棒性的影响。  相似文献   

9.
Uncertainty is a critical factor that pervades all aspects of electric-utility planning. Uncertainties about future load growth, about the continued performance of existing supply and demand resources, and about the costs, construction times, and operations of new resources greatly complicate utility resource acquisition. This paper discusses the factors that lead to uncertainty, reviews the methods that utilities use in planning and in acquiring resources, and suggests future research to help deal with these uncertainties. This review is based on assessments of the long-term resource plans prepared by 10 utilities and one Public Service Commission, telephone interviews with staff at these 11 organizations and with staff at three consulting firms, and reviews of many other related publications.  相似文献   

10.
We show simple yet optimal results to update the inventory/capacity levels, expected profit, fill rates, and service levels of substitutable resources in response to an updating of the mean demand forecasts for the resources. We find that a change in the mean demand of one resource does not affect the optimal inventory level of any other resource. The results are obtained for demands with location‐scale distribution, and for a revenue structure satisfying a triangle property such that the manager will always use the inventory of a resource to meet her own demand first before using it for substitution. The results for updating the performance measures also extend to managers who maintain non‐optimal inventory/capacity levels. Implications for procurement, sales and operational planning, and multi‐store operations are discussed.  相似文献   

11.
许多现有的项目组合模型都认为项目集合可以在固定的计划期完成,但是在实际的项目执行过程中,决策者为了使得高收益的项目纳入项目集合中或者放弃风险高的项目来释放更多的资金,会选择对项目组合固定的计划期进行灵活性调整。同时,考虑到项目未来价值的不确定性,本文利用实物期权的二叉树模型给出了价值波动的公式,进而建立了同时受弹性时间段和价值波动影响的项目组合选择的新模型,对传统的计算项目价值的净现值法进行补充。通过GAMS/BARON对算例进行求解,验证了模型的合理性和有效性。结果表明:考虑弹性时间段和价值波动的影响会给更符合企业长期的发展战略,给企业带来更大的收益,该模型也为处理不确定情况下的项目组合问题提供了新思路和新方法。  相似文献   

12.
Managers of product development (PD) project portfolios face difficult decisions in allocating limited resources to minimize project or portfolio delay. Although PD projects are highly iterative (cyclical), almost all of the vast literature on project scheduling assumes that projects are acyclical. This article addresses this gap with a comprehensive analysis of 31 priority rules (PRs) on 18,480 portfolios containing 55,440 iterative projects. We find that the best PRs for iterative project portfolios differ significantly from those for acyclical ones, and that the best PRs at the project level differ from those at the portfolio level. The best PR depends on project and portfolio characteristics such as network density, iteration intensity, resource loading profile, and amount of resource contention. In particular, by amplifying the effects of iteration, high‐density networks hold dramatically different implications for iterative projects. Moreover, the best PR also differs depending on whether the objective is to minimize the average delay to all projects or to minimize delay to the overall portfolio. Thus, a project or portfolio manager who uses the same PR on all occasions will exhibit unnecessarily poor performance in most cases.  相似文献   

13.
Product development occurs in multiproject environments where preemption is often allowed so that critical projects can be addressed immediately. Because product development is characterized by time-based competition, there is pressure to make decisions quickly using heuristics methods that yield fast project completion. Preemption heuristics are needed both to choose activities for preemption and then to determine which resources to use to restart preempted activities. Past research involving preemption has ignored any completion time penalty due to the forgetting experienced by project personnel during preemption and the resulting relearning time required to regain lost proficiency. The purpose of this research is to determine the impact of learning, forgetting, and relearning (LFR) on project completion time when preemption is allowed. We present a model for the LFR cycle in multiproject development environments. We test a number of priority rules for activity scheduling, activity preemption, and resource assignment subsequent to preemption, subject to the existence of the LFR cycle, for which a single type of knowledge worker resource is assigned among multiple projects. The results of the simulation experiments clearly demonstrate that LFR effects are significant. The tests of different scheduling, preemption, and resource reassignment rules show that the choice of rule is crucial in mitigating the completion time penalty effects of the LFR cycle, while maintaining high levels of resource utilization. Specifically, the worst performing rules tested for each performance measure are those that attempt to maintain high resource utilization. The best performing rules are based on activity criticality and resource learning.  相似文献   

14.
This paper examines headquarters allocation of resources to specific innovation transfer projects within the multinational enterprise between sending and receiving subsidiaries, focusing on the role of the subsidiary hosting the transfer. Resource allocation is of key strategic importance for the organization given that resources are limited in the multinational enterprise and that headquarters is the principal actor in distributing resources internally between competing innovation transfer projects. Findings from a dataset of 169 innovation transfer projects reveal that headquarters tend to favor established lines of innovation at the subsidiary level, as opposed to overall subsidiary operational relatedness for additional corporate resources. It is found that headquarters also tend to allocate resources to acquired subsidiaries' transfer projects to a higher degree than to those of greenfield ones. A curvilinear effect is found for subsidiary bargaining power which is initially positive and subsequently negative. The results highlight that certain subsidiary and innovation traits are determinants of headquarters resource allocation.  相似文献   

15.
The rising cost of resources within an organization, increasing capability of information technology, the need to conduct project at different places and availability of competent and inexpensive manpower elsewhere have promoted many companies to adopt project development in a virtual environment. Large scale projects have several full fledged projects conducted by different organizations. Therefore, such projects are called the project of projects (PoPs) here. As PoPs are influenced by stakeholders throughout the project lifecycle, the integration of various projects becomes challenging due to the risks associated with misaligned perceptions, cost, schedule, quality, human resources and communication.This paper describes project context and influencing factors for a PoP's progress in virtual environment and they are explained in terms of two case projects conducted by the author. It is highlighted that communication is an important issue when projects are conducted in virtual environment with different work culture. The communication models and case examples provided here are expected to add knowledge to managing projects in virtual environment.  相似文献   

16.
In this paper we present a general model and solution methodology for planning resource requirements (i.e., capacity) in health care organizations. To illustrate the general model, we consider two specific applications: a blood bank and a health maintenance organization (HMO). The blood bank capacity planning problem involves determining the number of donor beds required and determining the size of the nursing and support staff necessary. Capacity must be sufficient to handle the expected number of blood donors without causing excessive donor waiting times. Similar staff, equipment, and service level decisions arise in the HMO capacity planning problem. To determine resource requirements, we develop an optimization/queueing network model that minimizes capacity costs while controlling customer service by enforcing a set of performance constraints, such as setting an upper limit on the expected time a patient spends in the system. The queueing network model allows us to capture the stochastic behavior of health care systems and to measure customer service levels within the optimization framework.  相似文献   

17.
In a globalized economy, multinational enterprises (MNEs) pursue competitiveness through cross-border knowledge exploitation and exploration in international R&D. It is conventionally assumed that for subsidiaries to effectively access co-location advantages in knowledge milieus abroad, high levels of resource commitment are required. This paper analyses the relationship between resource commitment and access to co-location advantages, first theoretically and then through a case study of two MNEs in high-tech industries. We disaggregate the composite concept of resource commitment and demonstrate the dimensions accentuated, respectively, by the resource-based view, transaction cost economics and institutional theory. Next, we analyse the relationship between resource commitment and co-location advantages for 11 R&D subsidiaries of the two MNEs. Based on this analysis, we discuss the relationships between the empirical findings and the theoretically differentiated resource commitment dimensions. The study finds that high resource levels are less important for access to co-location advantages than conventionally assumed, while the level of commitment associated with allocated resources appears consistently to be important, lending more support for the relevance of institutional theory-related dimensions of resource commitment than the resource-based view-related ones. We also find support for the claim that more flexible governance arrangements promote access to co-location advantages in asset exploration.  相似文献   

18.
首先,本文在已有可打断项目组合选择模型的基础上,引入了消耗性资源和可更新资源约束,构建了一个更符合实际的新模型;其次,为了达到模型简化的目的,本文给出了资金约束的现值表示,并给出了理论证明;最后,利用GAMS对模型进行了算例分析。数值实验结果表明:1)资源约束下的项目打断有时可以给企业带来积极效益,这有别于已有的研究;2)在考虑资源约束的情况下,资源消耗少且同时收益高的项目应优先执行;3)当资源的供给量较少时,资源约束是决定项目选择的关键因素。此外,通过企业实际的案例对数值实验结果进行了验证。  相似文献   

19.
True synergy, as an organizational design, is uncommon in medical groups. This article addresses the experiences of a medical group that practiced an extreme form of synergy--the total equality of its physicians--since its inception almost 30 years ago. Synergy is the close coordination of the efforts and resources of individuals working together so that the performance of the whole is greater than the sum of the parts. Why use synergy in organizational design? By flattening the hierarchical levels, synergy addresses key issues of power (control, resource allocation, planning) and money (salary, bonuses, benefits), treating all physicians as equal partners. It also ensures access to the highest-quality candidates because the lure of equality, ownership, and permanence is so powerful. Synergy in medical groups works best where there is: A clearly stated mission and vision statement, as well as specific goals and objectives; careful selection of associates; a small group of between seven and nine members; a short-term duration of ten years or less; and a certain simplicity, whereby the group avoids risk-prone ventures or projects that distract it from its original mission and vision.  相似文献   

20.
冗余资源配置条件下的企业技术创新激励合约研究   总被引:1,自引:1,他引:1  
基于多任务委托代理模型的分析框架,建立了企业同时采用新增资源投入和搜寻企业冗余资源进行技术创新的信息不对称条件下的委托代理模型。通过对模型的分析,得出了企业技术创新所需的新增资源和冗余资源投入的优化配置条件,以及2种资源组合配置模式下的企业员工技术创新活动的最优激励合同条件。企业可以根据新增资源的边际收益、边际成本,以及各行动之间成本函数的相互依存性的不同组合,采取适度激励、重度强化激励、轻度强化激励、重度弱化激励和轻度弱化激励等优化激励组合方案来激励员工进行技术创新活动,从而使企业技术创新资源的配置有更多优化方案选择,以降低企业创新的风险和成本,提高资源效率和创新绩效。  相似文献   

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