工期-费用权衡问题的两个不确定机会约束规划模型

项目调度问题是指管理者通过资源分配,延长或缩短某些工序的持续时间,达到项目费用和工期之间的平衡。在实际工程项目中,环境的不确定性往往是项目管理者需要考虑的因素之一。本文应用不确定理论描述不确定环境中的项目调度问题,将每道工序的持续时间分为正常持续时间和可变动持续时间。其中,假设工序的正常持续时间为不确定变量,可变动持续时间为决策变量,分别构建在项目费用和项目工期约束下的两个不确定机会约束规划模型。依据不确定变量运算法则,将所建立的不确定规划模型转化为等价的确定模型。最后,通过一个工程实例验证模型的合理性。

Two Uncertain Chance-constrained Programming Models for Time-cost Trade-off Problem

Project scheduling problem is to determine the schedule of allocating resources so as to balance the total cost and completion time of a project.The uncertainty of the environment is an important factor in the process of project implementation.In this paper,an uncertain project scheduling problem is described based on uncertainty theory,in which the duration of each activity is divided into normal duration and change duration.Assume that the normal duration be an uncertain variable and take the change duration as decision variable.Two uncertain chance-constrained programming models are proposed under the constraint of project cost and project duration in order to satisfy different management requirements.To solve above the models,the uncertain chance-constrained programming models are transformed into equivalent deterministic programming models based on the operational law of uncertain variables.Finally,a numerical example is illustrated to show the reasonable of models.