Exact project reliability for a multi-state project network subject to time and budget constraints

• Published in: Reliability engineering & system safety Vol. 195; p. 106744
• Main Authors: Huang, Ding-Hsiang, Huang, Cheng-Fu, Lin, Yi-Kuei
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01.03.2020; Elsevier BV
• Subjects: Algorithms; Budgets; Computer applications; Decomposition; Exact project reliability; Human resources; Lower boundary points; Multi-state project network (MPN); Network reliability; Project feasibility; Reliability analysis; Reliability engineering; State vectors; Subsets; Upper boundary points; Weather; Multi-state project network (MPN); Decomposition; Exact project reliability; Upper boundary points; Lower boundary points; Subsets
• ISSN: 0951-8320; 1879-0836
• DOI: 10.1016/j.ress.2019.106744

•A multi-state project network is modeled to analyze a complex project.•Simplified subsets are decomposed from all feasible project state vectors.•Exact project reliability is evaluated under time and budget constraints.•An algorithm is proposed to derive project reliability based on the subsets.•A real project of mauufacturing lines is analyzed with sensitivity analysis. In a project, the duration of every activity is uncertain because of weather, availability of machines, human resources, and unexpected situations, and the cost is influenced by the duration. For modeling the uncertain durations, a multi-state project network (MPN) is proposed. To understand the performance of an MPN, project reliability is calculated and defined as the probability that a project can be completed within time and budget constraints. All feasible project state vectors are contained in upper and lower boundary points. The previous literature only calculated an estimated project reliability. To obtain the exact project reliability, a decomposition approach is developed to obtain subsets of feasible project state vectors. Each subset is firstly formed in terms of one upper boundary point and all lower boundary points. Each subset is further simplified to reduce the number of lower boundary points for computational efficiency. An algorithm with the decomposition approach is subsequently proposed to evaluate the exact project reliability. A real project of new manufacturing lines is demonstrated with several combinations of time and budget constraints to show the effectiveness of the proposed algorithm, and project managers can make decisions based on project reliability.