Improved Software System for Calculating the Reliability Indicators of Complex Technical Systems

The article analyses the literature sources, which investigate the existing methods and means of calculating reliability indicators of complex technical (in particular, software) systems. The reliability model of a modern complex technical system is often depicted in the form of a reliability block diagram (RBD), which may contain thousands of elements, each transitioning between different states (e.g., operational, failed, restored). This leads to a vast space of possible states in the corresponding Markov model. The reliability behaviour of a system is commonly described by a graph, with nodes representing system states and edges representing possible transitions between these states. A number of software products can be used to automate the calculation of reliability indicators for complex technical systems. However, these products have several limitations, including: difficulty in implementing into design and development processes; significant costs for licenses and staff training; lack of compatibility with other reliability analysis and life cycle management products; lack of tools for working with databases, etc. Most of the outdated products are desktop applications with an insufficiently user-friendly graphical interface. The primary objective of this work is to develop an improved software system that includes the modification and implementation of a recursive algorithm for forming an operability condition and visualizing a circular graph of states/transitions. With the help of the system, it is possible to automate the construction of reliability flowcharts for complex technical, in particular, software systems, calculate the operability condition using an improved recursive algorithm and method for determining the operability condition, determine the system states and visualize them using an n-ary or circular graph. Additionally, the system offers tools for calculating reliability indicators: availability and downtime factors, time between failures, failure flow parameters, etc. The advanced software system enables automated calculation of reliability indicators for software systems of any complexity level and reduces the influence of the human factor in the process of reliability design.