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101.
The design and development of large-scale software projects is a complex endeavor, often facing problems like cost and schedule overruns as well as low quality. Over the last years the management of software development projects has been recognized as the cornerstone point of seeking improvement and solutions. Simulation modeling of the software project process is gaining interest among academics and practitioners, as a method to tackle the complex questions with which relevant enterprises are confronted. It offers support on several issues, such as defining software product development strategies, decision-making regarding process improvement and training, in a time span ranging from a short portion of the life cycle to long term product evolution, with organization-wide implications. The aim of this work is to implement a model simulating a core part of a software project process, enabling the estimation of several project development details such as delivery times and quality metrics. The purpose of the model is to assist project managers in control and monitoring, but also in identifying the best planning alternatives. The model scope covers a portion of the life cycle of an incremental software development venture. 相似文献
102.
建设项目投资风险指标及模糊综合度量的研究 总被引:1,自引:0,他引:1
风险管理是建设项目管理的一个非常重要的方面,而风险指标是反映建设项目风险状况进行风险分析的一个重要内容.许多的学者对风险指标做过研究,其中大部分涉及的是经济评价和财务评价指标,或者使用损失期望值和方差的代数运算作为指标.本文在分析及总结前人风险指标研究成果的基础上,提出建设项目成本、时间和财务三方面的有关风险指标,并给出各指标的说明和计算公式.为综合评价建设项目的风险,本文利用了效用理论的思想和模糊理论方法,并以实例说明此模糊综合评价的具体计算步骤. 相似文献
103.
在模糊集上定义了模糊风险落影、模糊贝叶斯风险等概念 ,探讨了相关的定理与性质 ,研究了几种模糊风险决策的测量方法 ,给出了比较几类风险落影函数的“风险势”的概念 . 相似文献
104.
文平 《数学的实践与认识》2007,37(21):5-10
由于计划评审技术存在的不足,导致项目管理存在一定的偏差.对计划评审技术中的活动期望时间和方差的公式做了改进,从而提高了项目管理的精确性.还指出计划评审技术中活动期望时间和方差的计算公式,实际上是改进后公式的特殊情形. 相似文献
105.
We treat with tools from convex analysis the general problem of cutting planes, separating a point from a (closed convex)
set P. Crucial for this is the computation of extreme points in the so-called reverse polar set, introduced by E. Balas in 1979.
In the polyhedral case, this enables the computation of cuts that define facets of P. We exhibit three (equivalent) optimization problems to compute such extreme points; one of them corresponds to selecting
a specific normalization to generate cuts. We apply the above development to the case where P is (the closed convex hull of) a union, and more particularly a union of polyhedra (case of disjunctive cuts). We conclude
with some considerations on the design of efficient cut generators. The paper also contains an appendix, reviewing some fundamental
concepts of convex analysis.
Supported by NSF grant DMII-0352885, ONR grant N00014-03-1-0188, INRIA grant ODW and IBM. 相似文献
106.
提出一种工程问题的Petri网模型及其构造方法,并且通过该Petri网模型及其可达标识图,给出了整个工程的关键路径和合理施工方案的求解方法. 相似文献
107.
Scheduling project networks with resource constraints and time windows 总被引:10,自引:0,他引:10
Project networks with time windows are generalizations of the well-known CPM and MPM networks that allow for the introduction of arbitrary minimal and maximal time lags between the starting and completion times of any pair of activities.We consider the problem to schedule such networks subject to arbitrary (even time dependent) resource constraints in order to minimize an arbitrary regular performance measure (i.e. a non-decreasing function of the vector of completion times). This problem arises in many standard industrial construction or production processes and is therefore particularly suited as a background model in general purpose decision support systems.The treatment is done by a structural approach that involves a generalization of both the disjunctive graph method in job shop scheduling [1] and the order theoretic methods for precedence constrained scheduling [18,23,24]. Besides theoretical insights into the problem structure, this approach also leads to rather powerful branch-and-bound algorithms. Computational experience with this algorithm is reported. 相似文献
108.
彭运芳 《数学的实践与认识》2004,34(6):77-81
介绍了用于多方案比较的 3种动态分析法的原理及应用 ,从数学上证明了利用这三种方法进行方案比较所得的结论之间的关系 . 相似文献
109.
110.