A Fuzzy Control System for Estimating the Total Project Duration in GERT Networks

Project scheduling is one of the main fundamentals in project management so the related progressive methods which consider most of the project limitations would be valuable. The GERT (Graphical Evaluation and Review Technique) is a network analysis method which has unique capabilities in comparison with other conventional scheduling methods. On the other hand and, there is no definite conformity between the scheduling and implementation of projects mostly in the reality. So a project always accompanied by uncertainty. In this research, for decreasing the constraint’s consequences, caued by ambiguity and indecisiveness, fuzzy logic and fuzzy control system has been recommended. For this purpose, the mean, variance, value and number of loops in the GERT network and also environmental effective risks has been considered as fuzzy variables. Thus, by using capabilities of GERT network and with emphasis on fuzzy logic and fuzzy system, a fuzzy control system has been designedfor the first time. In accordance with the results obtained from 15 experiments which was done among different medium-sized projects, it could be assert that, by using the designed control system, scheduling the project in a more logically and precisely way would be achievable