Effects of variability on the due-time performance of a continuous materials flow production system in series

Abstract

In this study, we consider a specific continuous materials flow production system with N unreliable stations in series and no interstation buffers. Processing times of the stations are deterministic and Identical. We assume that the failures are time-dependent and the time to failure and time to repair distributions are exponential and two-phase balanced coxian (C-2:b), respectively. The effects of repair time variability on the performance of the production system are investigated by changing the parameters of C,, distribution. We obtained closed-form expressions for the asymptotic mean and variance of the amount of materials produced in this production system. It is shown that the amount of materials produced in a fixed time interval is normal as time approaches infinity. The asymptotic distribution of the amount of materials produced is used to derive the probability of meeting a customer order on time. We used this probability to evaluate the due-time performance of the production system. Numerical experiments that investigate some relationships among the performance measures and the system parameters are also presented.