A Study On Fuzzy Resource Constrained Multi-project Scheduling With Uncertain Transfer Times

Resource constrained multi-project scheduling problem has gradually become a very important issue in the field of project management, and attracted much attention of the scholars, as the problem widely exists in the operation of enterprises whose size is increasing quickly. There is almost no studies on resource transfer time in traditional resource constrained multi-project scheduling theory. A few scholars did research on transfer time, however, all of them didn’t consider the uncertainty of transfer time, duration of activities and so on which reduces the practical value of the studies greatly. To solve this problem, this paper integrates the uncertainty of transfer times and duration of activities into resource constrained multi-project scheduling problem by combining with fuzzy theory to use triangular fuzzy numbers to represent transfer times and duration of activities. And then a model of resource constrained multi-project scheduling problem with uncertain transfer time and duration of activities which is object to minimizing the total duration of multi-project is established. Furthermore, a new genetic algorithm based on fuzzy priority rules is designed considering the shortage of traditional methods and the need of solving the model. Eventually, we solve the model by using the designed algorithm based on a numerical example and achieve the fuzzy optimal scheduling scheme.The resource constrained multi-project scheduling problem with uncertain transfer time is more consistent with the reality comparing to the multi-project scheduling problem with certain transfer time. The fuzzy optimal scheduling scheme is more flexible and efficient while the certain optimal scheduling scheme need stringently stable process of the scheduling. When a task of resource transfer or an activity is interrupted to change, the fuzzy optimal scheduling scheme can maintain its effectiveness through adjusting the scheduling of the next stage timely. This will improve the possibility of completing the project ahead and reduce the possibility of project delays or even failure.