A Heuristic Method to Upgrade System Availability For Hot or Cold Standby, and Voting Systems

This paper details a new heuristic-based method for optimizing system availability by redundant allocation. Hot or cold standby, majority voting, repair crew, or other type of logic systems are easily handled. A computer program, Upgrading of System Availability Package (USAP), has been developed and is available from the authors. This program assesses and upgrades system availability when the component availability and system configuration are known, If the system availability needs to be improved and funds are available for such an improvement, then USAP suggests a system configuration that has the desired system availability within a given cost constraint. The algorithm is based on cut sets, so both fault trees and block diagrams can be handled. No special subroutines which specify the functional form of the system availability are required. This makes the program easy to implement on a personal computer, since no linking and compiling of special routines are needed. The upgrading program in USAP provides good results as compared to other upgrading methods found in the literature. This simple and intuitive analysis gives practical solutions for very large, complicated systems.