Affiliations: Department of Mathematics, National Institute of Technology-Puducherry, Karaikal, India | Department of Mathematics, Seacom Engineering College, Sankrail, Howrah, India | Department of Mathematics, Jadavpur University, Kolkata, West Bengal, India
Note: [] Corresponding author. G.S. Mahapatra, Department of Mathematics, National Institute of Technology-Puducherry, Karaikal 609605, India. Tel.: +91 9433135327; Fax: +91 4368231665; E-mail: g_s_mahapatra@yahoo.com
Abstract: The probabilistic reliability estimation of complex system is complicated due to uncertainty of failure data, modeling or human failure. In this paper, reliability of components of complex network system is considered as fuzzy in nature to reduce the uncertainty. Trapezoidal fuzzy number is used to represent component's reliability of network system. Then the reliability of the network system is assembled with fuzzy reliability of components and evaluated by Zadeh's extension principle. Fuzzy reliability of the network system becomes an interval by α-cuts operation. Interval nonlinear programming is used to evaluate the optimum network's system reliability with interval valued cost constraint. The above approach is explained in details through a numerical example of very useful power system network of electrical engineering.
