A Project Scheduling Method Based on Fuzzy Theory

In this paper a new method based on fuzzy theory is developed to solve the project scheduling problem under fuzzy environment. Assuming that the duration of activities are trapezoidal fuzzy numbers (TFN), in this method we compute several project characteristics such as earliest times, latest times, and, slack times in term of TFN. In this method, we introduce a new approach which we call modified backward pass (MBP). This approach, based on a linear programming (LP) problem, removes negative and infeasible solutions which can be generated by other methods in the backward pass calculation. We drive the general form of the optimal solution of the LP problem which enables practitioners to obtain the optimal solution by a simple recursive relation without solving any LP problem. Through a numerical example, calculation steps in this method and the results are illustrated.

[1]  Caroline M. Eastman,et al.  Review: Introduction to fuzzy arithmetic: Theory and applications : Arnold Kaufmann and Madan M. Gupta, Van Nostrand Reinhold, New York, 1985 , 1987, Int. J. Approx. Reason..

[2]  S. H. Nasution Fuzzy Critical Path Method , 1994, IEEE Trans. Syst. Man Cybern. Syst..

[3]  S. Chanas,et al.  THE USE OF FUZZY VARIABLES IN PERT , 1981 .

[4]  Jing-Shing Yao,et al.  Fuzzy critical path method based on signed distance ranking of fuzzy numbers , 2000, IEEE Trans. Syst. Man Cybern. Part A.

[5]  Jing-Shing Yao,et al.  Fuzzy Critical Path Method Based on Signed-Distance Ranking and Statistical Confidence-Interval Estimates , 2003, The Journal of Supercomputing.

[6]  Hans-Jürgen Zimmermann,et al.  Fuzzy Set Theory - and Its Applications , 1985 .

[7]  Y. Ku,et al.  Introduction to fuzzy arithmetic—theory and applications : Arnold Kaufmann and Madan M. Gupta. 351 pages, diagrams, figures. Van Nostrand Reinhold Company, New York, 1985. , 1986 .

[8]  Mitsuo Gen,et al.  An efficient approach for large scale project planning based on fuzzy Delphi method , 1995, Fuzzy Sets Syst..

[9]  Dorota Kuchta,et al.  Use of fuzzy numbers in project risk (criticality) assessment , 2001 .

[10]  A. Kaufmann,et al.  Introduction to fuzzy arithmetic : theory and applications , 1986 .

[11]  Pawel Zielinski,et al.  Critical path analysis in the network with fuzzy activity times , 2001, Fuzzy Sets Syst..

[12]  Ching-Lai Hwang,et al.  Fuzzy Multiple Attribute Decision Making - Methods and Applications , 1992, Lecture Notes in Economics and Mathematical Systems.

[13]  Igor Gazdik Fuzzy-Network Planning - FNET , 1983, IEEE Transactions on Reliability.

[14]  C. McCahon Using PERT as an approximation of fuzzy project-network analysis , 1993 .

[15]  Didier Dubois,et al.  Possibility Theory - An Approach to Computerized Processing of Uncertainty , 1988 .

[16]  Aminah Robinson Fayek,et al.  Fuzzy Logic Approach for Activity Delay Analysis and Schedule Updating , 2005 .

[17]  Osama Moselhi,et al.  Project-network analysis using fuzzy sets theory , 1996 .