Optimal Redundant Units and Load in Parallel Systems

병렬 시스템에서의 최적 중복부품수와 최적 부하수준

  • Published : 1998.03.01


This paper is concerned with a parallel system that sustains a time-independent load and consists of n components with exponential lifetimes. It is assumed that the total load is shared by the working components and the failures of components increase higher failure rates in the surviving components according to the relationship between the load and the fialure rates. The power rule model among several load-failure rate relationships is considered. We consider the system efficiency meausre as the expected profit earned by the system per unit time. The high load causes high gain but it also occurs frequent system failures. The expected profit per unit time is used as criterion to evaluate the system efficiency. The goal of system engineer is to determine the optimal load and redundant units maximizing the expected profit per unit time. First, the system reliability function is obtained and the optimization problem of the load-sharing parallel system is considered. Given the redundant units, the existence of the optimal load can be proved analytically and given the load, the optimal redundant units can be solved also analytically. The optimal load and redundant units are obtained simultaneously by numerical computation. Some numerical examples are studied.



  1. J.Opl.Res.Soc. v.37 A Problem in Reliability Optimization Filus, J.
  2. Reliability In Engineering Design Kapur, K.C.;Lamberson, L.R.
  3. Reliability Engineering Handbook v.2 Keccecioglu, D.
  4. IRE Trans. PGROQC Accelerated Life Testing of Capacitor Levenbach, G.I.
  5. IEEE Trans. Reliability v.42 A Multivariate Exponential Shared-Load Model Lin, Hsin-Hui;Chen,Kang-Haw;Wang, Rong-Tsorng
  6. Naval Research Logistics Quarterly v.31 A Load Sharing Model: The Linear Breakdown Rule Schechner,Z.
  7. IEEE Trans Reliability v.R-37 Reliability of a m out of n System When Component Failure Induces Higher Failure Rates in Survivors Scheuer,E.M.
  8. IEEE Trans Reliability v.40 Modeling a Shared-Load K-out-of-n:G System Shao, J.;Lamberson, L. R.
  9. 한국 과학 기술원, 석사 학위논문 부품의 고장이 잔여 작동 부품의 고장률을 증가시키는 k-out-of n:G 시스템의 신뢰도, 가용도 및 최적 중복 부품수 도형찬