M Ghazanfari - Department of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran
K Shahanaghi - Department of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran
A Yousefli - Department of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran

Activity duration is uncertain due to the variations in the real world such as weather, resource availability, etc. Utilization of uncertain planning leads to project scheduling with more stability against environmental variations. This paper presents a new optimal model for time-cost trade-off problem in fuzzy environment. In order to solve this problem, we develop a new possibility goal programming approach. Significant feature of this model is determination of optimal activity duration in form of triangular fuzzy numbers. To validate the algorithm developed here, a case study will be presented.

time-cost trade off, possibility goal programming, fuzzy sets, fuzzy decision variable