关键词: 设计评审, 耦合任务, 随机返工, 连续时间马尔可夫链, 相型分布, 模具设计

Abstract: To effectively evaluate the reviewing strategies for coupled design tasks with general activity durations and random rework,an analytical model for estimating the probability distribution of project completion time was constructed based on the phase-type distribution and continuous-time Markov chain.After analyzing two general distribution approximation methods based on squared?coefficient of variation,a more efficient method was selected to approximate the normal and rework activity duration.The project network was transformed by regarding each phase as a virtual task and the state transitions of the transformed network were described by a continuous-time Markov chain.The probability distribution of project completion time was finally obtained based on the phase-type distribution.Computational experiments were carried out taking a typical mold design project as an example,in which the influence of the project environmental parameters on the performance of reviewing strategy was analyzed.The proposed model and method were also verified by case study of mold design project.

Key words: design reviewing, coupled-tasks, random rework, continuous-time Markov chain, phase-type distribution, mold design