A fuzzy random resource‐constrained scheduling model with multiple projects and its application to a working procedure in a large‐scale water conservancy and hydropower construction project

The aim of this paper is to deal with resource‐constrained multiple project scheduling problems (rc‐mPSP) under a fuzzy random environment by a hybrid genetic algorithm with fuzzy logic controller (flc‐hGA), to a large‐scale water conservancy and hydropower construction project in the southwest region of China, whose main project is a dam embankment. The objective functions in this paper are to minimize the total project time (that is the sum of the completion time for all projects) and to minimize the total tardiness penalty of multiple projects, which is the sum of penalty costs for all the projects. After describing the problem of the working procedure in the project and presenting the mathematical formulation model of a resource‐constrained project scheduling problem under a fuzzy random environment, we give some definitions and discuss some properties of fuzzy random variables. Then, a method of solving solution sets of fuzzy random multiple objective programming problems is proposed. Because traditional optimization techniques could not cope with the rc‐mPSP under a fuzzy random environment effectively, we present a new approach based on the hybrid genetic algorithm (hGA). In order to improve its efficiency, the proposed method hybridized with the fuzzy logic controller (flc) concept for auto‐tuning the GA parameters is presented. For the practical problems in this paper, flc‐hGA is proved the most effective and most appropriate compared with other approaches. The computer generated results validate the effectiveness of the proposed model and algorithm in solving large‐scale practical problems.