A genetic algorithm-based optimizing approach for project time-cost trade-off with uncertain measure

Hua Ke

doi:10.1186/2195-5468-2-8

Abstract

Both the trade-off between the project cost and the project completion time and the indeterminacy of the environment are important issues for real-life project managers. In this paper, an uncertain time-cost trade-off problem, where activity cost functions are assumed to be linear and the objective function to be minimized is the project direct cost, is described based on uncertainty theory. Two uncertain time-cost trade-off models are built to satisfy different management requirements. To solve the proposed models, two equivalent crisp mathematical programming models are given, and genetic algorithm is introduced to search for quasi-optimal schedules. For future research, resource constraints or more types of indeterminacy can be included.

Highlights

For real-life projects, decision-makers should always consider the trade-offs among the performance goals for project scheduling and control, especially the trade-off between project completion time and project cost
Risk-averse managers usually want to find the optimal decision with minimum expected project cost subject to some project completion time constraint
Due to the environmental complexity, these performance goals are not always obtained completely. It is natural for the project manager to maximize the chance that the project cost does not exceed the given budget under some project completion time constraint, which follows the philosophy of dependent-chance programming (DCP) introduced by Liu [39]

Summary

Introduction

For real-life projects, decision-makers should always consider the trade-offs among the performance goals for project scheduling and control, especially the trade-off between project completion time and project cost. Zahraie and Tavakolan [12] embedded two concepts of time-cost trade-off and resource leveling and allocation in a stochastic multiobjective optimization model, where fuzzy set theory was applied to represent different options for each activity. Ke et al [15] modeled stochastic project time-cost trade-offs with time-dependent activity durations. To the knowledge of the authors, no researchers considered time-cost trade-off problem in uncertain environment, which is not either stochastic or fuzzy.

Results

Conclusion