Fuzzy project scheduling system for software development

This paper presents an FPS (Fuzzy Project Scheduling) decision support system applied to software project scheduling. The purpose of the FPS system is to allocate resources (software engineers) among dependent activities (system design, user interface design, modules implementation, modules integration and tests), taking into account one of two criteria: project completion time and maximum lateness, under uncertain time parameters of activities. By time parameters we understand durations, ready times and due dates of particular activities. Uncertainty of these parameters is modelled by means of L-R fuzzy numbers. A general procedure for transforming the fuzzy scheduling problem into a set of associate deterministic problems is based on the use of α-cuts. Optimistic and pessimistic schedules are heuristically generated for given α-levels. Aggregation of optimistic and pessimistic values of a minimized criterion for all α-levels gives a fuzzy result. Comparison of fuzzy result is based on a compensation of areas determined by the membership functions. The FPS system is described and its application to software project management is presented on a real example.