Zaslavskyy V. Investigation of complex systems with high cost of failure.

Dissertation is dedicated to the development and improvement of optimizational mathematical models, algorithms and specialized DSS software to solve a complex scientific and applied problems consisting in provision of highly reliable long terms operation of complex systems with high cost of failure. The methodological elements developed for complex systems high cost of failure allowed to define their main features and specify interconnected problems for their life cycle stages. Optimal redundancy allocation problem, formation of various types of complexes of nondestructive examination methods, system maintenance and risk management are considered and solved. Concept of mathematical models and optimization algorithm development that is based on system analysis principles and type-variety principle is presented. Type-variety principle consists in goal-oriented use of different components (systems, elements, algorithms) that execute the alike functions, and their joint use and interaction eliminates the possibility of common cause failure. This approach allows increasing system reliability level and operation time. Developed models and algorithms provide scientific and methodological basis (framework) to increase reliability of complex systems with high cost of failure for life cycle stages. They are being in DSS for different problem areas and have been implemented in design and exploitation of complex systems (satellites, land base launch systems, nuclear power plants, banks and payment systems, etc.).