基于梯形模糊数的项目缓冲确定方法研究  

Determination of Project Buffer Based on the Trapezoidal Fuzzy Number

作　　者：张俊光[1] 宋喜伟 贾赛可 杨双[1] 

机构地区：[1]北京科技大学东凌经济管理学院,北京100083

出　　处：《管理工程学报》2015年第2期223-228,共6页Journal of Industrial Engineering and Engineering Management

基　　金：国家自然科学基金资助项目(71072123);教育部人文社科基金资助项目(10YJC630384);中央高校基本科研业务费资助项目(FRF-BR-12-020)

摘　　要：针对现有模糊方法未能对活动风险进行有效的定量评估问题,本文采用梯形模糊数确定项目风险,并基于风险确定项目缓冲。首先,因为风险是造成项目延期的主要原因,通过引入模糊方法和梯形模糊数对项目的风险进行计算;接下来根据确定的风险值,采用尾部集中法确定初步的项目缓冲;最后,针对中心极限定理假设任务活动时间相互独立的不足,运用网络复杂度和资源紧张度等项目属性对缓冲进行修正,得到最终的项目缓冲。实验结果表明,该方法设置的缓冲既能够对项目形成有效的保护,又能够避免缓冲的浪费。Buffer determination is a key component of critical chain project management. This element is an important means to shorten the project duration, reduce waste of the safety time, and improve the project efficiency through the determination of project buffer. Therefore, it is very critical for the success of the project to use a perfect and accurate buffer determination method. Unfortunately the project is often lack of historical data, so it is difficult to apply statistical methods to determine the project buffer. At the same time, the future condition of the project is difficult to predict, so using fuzzy theory to determine project buffer has become mainstream research. In addition project risk is the main cause of project safety time and project buffer, but the existing fuzzy buffer research methods have failed to achieve the effective evaluation of the project risk. Therefore, the proposed method adopts the trapezoidal fuzzy number of fuzzy theory to evaluate the risk of the project, and determine the project buffer according to project risk taking into account the attributes of the project. The activity risks were originally identified as the main reason for project delay based on the assumption that the duration of project activities obeys lognormal distribution. By the analysis of L-R fuzzy number, the trapezoidal number was considered to be more appropriate for the description of the fuzzy interval. The fuzzy theory and the trapezoidal number were next adopted to estimate the risk of the project duration, and the completion time with 90% completion probability was obtained with total consideration of the agreement index. To overcome the deficiency of the central limit theorem, the resource tightness and the network complexity were then adopted to improve the model with the total consideration of the impact of the project attributes on the project duration. Thus, a new buffer sizing model was obtained based on the risk and the project attributes. The proposed method was eventuaily compared with the Cut a

关 键 词：关键链项目管理 缓冲确定 风险 梯形模糊数 项目属性 

分 类 号：F224[经济管理—国民经济]