Overview of System Reliability Modeling Tools

Abstract

Abstract. System reliability is a critical aspect of a system, which incurs the proposing of related modeling tools. Tools like Reliability Block Diagrams (RBD) and Fault Tree (FT) provide static representation of system reliability. RBD is a graphical representation that depicts a network of system components and connections. FT is a logical and diagrammatic method to evaluate an accident's probability that results from faults and failure events. The increasing complexity of systems drives the demands for analyzing system dynamic behaviors like dynamics, dependencies, redundancy and load sharing. Dynamic models like Dynamic Reliability Block Diagrams (DRBD) and Dynamic Fault Tree (DFT) are proposed. Dynamic tools define frameworks for modeling dynamic reliability behavior of systems. DRBD is an extending and enhancing of RBD by adding a state-events working mechanism, which permits to model dynamic reliability behaviors of the system. DFT is an extension of FT by adding the sequential notion which can meet time requirements. It is also important to verify these tools for locating and identifying deadlock and faulty states. The efficiency of verification techniques to model these modeling tools and the assessment of dynamic behaviors are taken as evaluation criteria. Based on current research, DRBD performs better than alternatives.

System reliability evaluation and dynamic optimization based on an improved reliability block diagram

“…To analyze system dynamic reliability behaviors, that is, dependency, redundancy and loading sharing, researchers proposed extended models like DRBD and DFT. 4 An RG is an acyclic digraph consisting of nodes and edges. Compared with RBD and FT, it is more suitable for modeling network system reliability.…”

“…By comparison, RBD has been more widely adopted in various applications due to the virtues of simplicity and readability. 4,9 As a top-down modeling technique, RBD is illustrated as a success-oriented network including an input, an output, and a set of blocks. Each block represents a constituent component with definite connections with other blocks.…”