Completion Time of Special Kind of GERT-Type Networks with Fuzzy Times for Activities

International Journal of Industrial Engineering

© 2018 by SSRG - IJIE Journal

Volume 5 Issue 1

Year of Publication : 2018

Authors : S.Tousheh Asl and S.S.Hashemin

10.14445/23499362/IJIE-V5I1P101

How to Cite?

S.Tousheh Asl and S.S.Hashemin, "Completion Time of Special Kind of GERT-Type Networks with Fuzzy Times for Activities," SSRG International Journal of Industrial Engineering, vol. 5,  no. 1, pp. 1-8, 2018. Crossref, https://doi.org/10.14445/23499362/IJIE-V5I1P101

Abstract:

Due to uncertainty in realization of some of the project activities, GERT-type networks are used. Also in these networks, duration of activities is non-deterministic. In this research, it is assumed that the probability of activity realization is known. Also, it is supposed that the activity durations can be shown as a positive trapezoidal fuzzy number. Studied networks don’t have any loops. They have one source node and they can have more than one target node. Based on simulation, a new algorithm is developed for acquisition of all sub networks of the project network. It is obvious that the completion time of project is a fuzzy random variable. So, the probability function and cumulative distribution function of completion time of the project are defined. These functions are obtained for each end node of the project. Therefore, mean and variance of completion times can be computed. Finally, an example has been solved using the new algorithm.

Keywords:

  GERT-type networks, Trapezoidal fuzzy number, Fuzzy random variable, Project completion time.

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