Application of Multi-Criteria Decision Making Techniques in Time-Cost-Quality Trade-Off

Discrete time-cost-quality trade-off problems (DTCQTPs) are a branch of project scheduling problem which deals with establishing a compromise between time, cost and quality. In this thesis, multi-objective optimization models, namely, genetic algorithm (GA) and improved harmony search (IHS), integrated with multiple criteria decision making (MCDM) methods are developed to solve the DTCQTPs with the aim to find the best optimal project scheduling alternative. Three different MCDM methods, e.g., evidential reasoning (ER), PROMETHEE, and TOPSIS are used to rank the Pareto-optimal solutions obtained through GA and IHS. The proposed methodology is applied to a benchmark construction project scheduling problem to investigate the efficiency of the proposed methods. The obtained results revealed that the ER approach which is a more complex MCDM methods when compared with PROMETHEE and TOPSIS can provide the DMs with a transparent view of each project scheduling alternative. Thus, detailed investigations is possible for the ER approach, while the PROMETHEE approach with a similar ranking of the solutions can be a useful substitution for the ER approach. The performance analysis showed that IHS algorithm is more efficient than GA while the former has a higher computational time. Keywords: discrete time-cost-quality trade-off problem (DTCQTP), multi-objective optimization models, genetic algorithm (GA), improved harmony search (IHS), multiple criteria decision making models, evidential reasoning (ER), PROMETHEE, TOPSIS.