以关键链方法中的二次资源冲突困境为切入点,从鲁棒调度优化角度提出一种解决策略.首先,采用定量化建模对问题进行数学描述和表达,剖析插入输入缓冲引起二次资源冲突的原理,进而采用场景分析法从复杂的冲突表象中分解出四种基本的冲突场景构成要素.其次,基于鲁棒调度优化理论,探究各种冲突子问题的有效对策并归类,据此开发出一种消除二次资源冲突的局部重调度启发式协调策略;根据策略设计基于两次调度进程和两类缓冲动态消耗的鲁棒性指标,采用鲁棒性关键链项目调度问题输出鲁棒性最大的调度方案.再次,设计仿真程序和三个测试指标:项目实际按期完工率、活动开始时间偏差绝对值之和及偏差绝对值的方差;基于ProGen随机地生成测试算例集合进行数值实验.结果发现,以鲁棒性调度方案为依据安排项目的实施过程,三个统计指标值都优于以传统关键链调度方案为依据时相对应的指标值.结论表明:基于鲁棒调度优化的二次资源冲突消除策略及设计的关键链鲁棒性指标在项目实施中具有较好的稳定性效果.
An effective strategy is proposed to solve the dilemma of second resource conflicts in the critical chain method (CCM) from a novel perspective of robust optimization. Firstly, this dilemma is mathematically expressed to gain a quantitative model, and the logic of the dilemma resulted from insertions of feeding buffers is explored. Then scenario analysis is adopted and four basic components are decomposed from the complex conflict phenomena. Secondly, based on robust scheduling optimization, some effective policies are investiga- ted and classified for all sub-problems of conflict situations, and a local rescheduling strategy is developed. Moreover, a robust index is designed based on the strategy, which combines the two scheduling progresses with dynamic consumptions of two kinds of buffers. The optimal schedule is an output when maximizing the ro- bust index. Extensive numerical experiments and three performance indicators are constructed, which include the realized probability that a project finishes on schedule, the sum of the absolute deviations between the ac- tual and the planned activity starting times and the variance of the absolute deviations for activity starting times. Extensive numerical experiments are also performed on the set of instances randomly generated by Pro- gen. The experimental results show the values of three statistical indicators under the schedule of the robust CCM are better than those under the schedule of the traditional CCM. Finally, the conclusions indicate that the strategy to deal with the second resource conflicts and the robust measure exhibits good stable effects during project implementation.