Markov's Modeling of NPP I&C Reliability and Safety: Optimization of Tool-and-Technique Selection

Markov's chains are widely applied in quantitative analysis of safety-critical systems. There are few roadblocks for greater application of the Markov's chains: accounting the additional hardware and software component (or FPGA) increases the model state-space and complicates analysis, the non-numerically sophisticated user may find it difficult to decide between the variety of numerical methods and tools to determine the most accurate for their application. Obtaining the high trusted modeling results becomes a nontrivial task. We present the metric-based approach for selection of the applicable solution technique based on the analysis of several Markov chain parameters. Three optimization criteria for informed tool selection were developed to support the decision-making between the wide set of applicable software. Presented approach and criteria are applied as the stepwise tools-and-techniques selection procedure that aims to reduce the risks, increase an accuracy and optimize time needed for Markov's chains analysis. Paper presents the case study of reliability and safety assessment for industrial Nuclear Power Plant Instrumentation and Control system using the optimized tools-and-techniques selection procedure.