en Other Other پژوهشی Original <p>An availability model is developed to optimize the availability of a series repairable system with multiple k-out-of-n subsystems in this paper. There are two types of decision variables that determine the system designer&rsquo;s decision to allocate the number of repairmen and to allocate the number of redundant components in each subsystem in the presence of weight, volume and cost constraints. As per the nonlinear structure of the objective in the model, the model is located into the nonlinear programming category. A classical Particle Swarm Optimization (PSO) algorithm is proposed to solve seven various instances of the model. The aim of this study is to illustrate the model and to propose an applicable algorithm for the problem. The efficiency of the proposed PSO is illustrated by comparison with Simulated Annealing (SA) method.</p> Repairable component, Redundancy allocation, Repairman, Availability optimization 0 0 http://iors.ir/journal/browse.php?a_code=A-10-522-1&slc_lang=en&sid=1 A. Eshraghniaye Jahromi eshragh@sharif.edu 00031947532846001398 00031947532846001398 No Sharif University of Technology Ali A. Yahyatabar Arabi aya6425@gmail.com 00031947532846001399 00031947532846001399 Yes Sharif University of Technology