Comparisons of standby and parallel systems in reliability, replacement, scheduling and application

This paper compares the standby and parallel systems through the following analyses: reliability measures such as reliabilities, mean times to failure, and failure rates are first compared. These comparisons are reconsidered when the number of units of the two systems cannot be predefined constantly but is a random variable that can be estimated. Replacement policies in which how many number of units should be provided for replacements are compared second. When the two systems work for the same job with a random processing time, their optimal scheduling problems are compared third by employing excess and shortage costs. Finally, the standby and parallel modes are applied into data transmission system, and their mean transmission times are compared. All comparative discussions are given analytically and numerically in exponential distributions, and their potential values could be explored in future studies.