Performance Assessment and Sensitivity Analysis of a Computer Lab Network Through Copula Repair with Catastrophic Failure

  • Praveen Kumar Poonia Department of General Requirement, Ibri College of Applied Sciences, Oman
Keywords: Computer lab, k-out-of-n: G system, sensitivity, catastrophic failure, Gumbel-Hougaard family copula distribution


The advent of copula distribution by Gumhel-Hougaard family spurred a new direction of research in multi-state complex engineering systems and is widely applied in various series-parallel systems. Considering this aspect, in this paper we study various reliability measures of a complex system consisting of eight identical computer labs as star topology working under 5-out-of-8: G policy, two different centralized data base servers working under 1-out-of-2: G policy, and a switch in series configuration. Failure rates of all the units are assumed to be constant and follow exponential distribution, while repair supports general distribution and copula distribution. The objective of this paper is to evaluate availability of the system, reliability of the system, mean time to failure and expected profit analysis by choosing arbitrary values of the parameters in a way that numerical solutions can be obtained systematically in a reasonable computational time. The problem is modelled using supplementary variable technique, Laplace transform and copula repair. We highlight the use of copula repair, while identifying the factors for improvement and future directions of work.


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Author Biography

Praveen Kumar Poonia, Department of General Requirement, Ibri College of Applied Sciences, Oman

Praveen Kumar Poonia is presently working as Assistant Professor in the Department of General Requirements, University of Technology and Applied Sciences, Ibri College of Applied Sciences, Ibri, Sultanate of Oman. Previously he served as a professor at Bharat Institute of Technology, Meerut, India for sixteen years under Dr. APJ Abdul Kalam Technical University, India. He received his Ph. D degree in Mathematics from Chaudhary Charan Singh University, Meerut, UP, India in 2005. He has published several research papers in renowned international journals. His research interests include reliability theory and reliability modelling. He is reviewer in various highly respected journals in the areas of Reliability, Statistics, and Optimization. Dr. Poonia has been a member/life member of various academic/professional bodies.


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