The optimal strategy of the structure control in queue and reliability model is studied by using controlled semi-Markov processes. The optimal strategy has been proved to be looked for in the class of threshold strategies.

The optimal strategy of the structure control in queue and reliability model is studied by using controlled semi-Markov processes. The optimal strategy has been proved to be looked for in the class of threshold strategies.

This paper proposes a new method of ranking of elements to ensure the reliability of systems with application of the fuzzy relations theory. The ranking problem is formulated as automatic classification on the basis of the transitive closure of similarity fuzzy relation. It makes possible to divide a set of system’s elements into disjoint classes undistinguishable by importance.

For construction of a similarity fuzzy relation, each element of a system is represented in the form of a vector of influences. A measure of similarity of pair of elements is the distance between two vectors. Degree of influence of each element is proposed to be calculated by a method of the least influence, which uses expert knowledge about the least influence of an element and comparison of other influences with it by the 9-point Saaty scale.

The proposed method is free from assumption on independence of elements and binary character of reliability: «there is a fault – there is no fault». Possible fields of application of the proposed method are systems with ill-defined structure and multifunctional elements, e.g. organizational, ergatic, military ones, etc.

The present work offers the method of estimation of economic efficiency indicators of the automated technological facility “protection object – safety system” with recoverable elements considering the uncertainty of a model’s parameters. The fuzzy estimation for the average profit of facility operation per time unit is obtained. The example of numerical evaluation of the examined indicator of efficiency with fuzzy parameters is given.

This paper covers the influence of structural and technological parameters of field metal-oxidesemiconductor-transistors (MOSFET) on reliability prediction in power-law dependence of lifetime tL from substrate current of Isu. The structural and technological parameters capable to influence degradation of MOSFET instrument characteristics caused by injection of hot carriers are defined. The author would like to express his gratitude to the research supervisor, Doctor of Technical Sciences, Professor Korobov A.I. for support of the present paper and a number of important comments.

This paper describes methodological difficulties when dealing with practical engineering challenges of reliability for non-stationary (time dependent/“ageing”) objects. A special case is considered when the object’s failure rate is linearly growing with operation time. An average lifetime of such object is defined. The result expression is reduced to the formula which is accessible to be used in engineering analyses. A formal way of substitution of a real non-stationary “ageing” object for a virtual stationary one is proposed. Besides, a constant failure rate of a virtual object is taken on the basis of additional considerations, in particular, on the basis of the condition ensuring the equality of the “life times” of both objects. The formulas are developed for calculation of the failure rate for a virtual stationary object, expressed through the parameters of the real object’s “ageing” characteristics. The efficiency of the suggested method is demonstrated by means of the solved problem about final probabilities of the states of the “linearly ageing” object and its availability factor, deduced in analytical form.

This article deals with the elaboration of definition of software reliability. This task is considered within the context of a generic terminological problem arisen due to the necessity to coordinate the Russian terminology with the definitions used in international practice. The paper represents a list of definitions of software dependability assumed to be a complex property. Several software properties specifying reliability are considered. The article also contains the table of applicability of these properties to describe the reliability of various types of software programs.

The paper considers the aspects of applicability of programmable control systems for nuclear power plants. The advantages and disadvantages of these systems have been identified. The main disadvantages of these systems have been singled out as follows: impossibility to prove the parameters of dependability of implemented control functions, susceptibility to potential cyber attacks. The paper offers the method of selecting automation means for implementing control systems using programmable and non-programmable automation means based on making a functional analysis of a nuclear power plant’s control systems.

This article represents the analysis of factors affecting the functioning of Vessel Traffic Service (VTS) at the stage of intended operation. Failures of such structural elements as technical facilities – coast radar and radio relay stations – affect the quality of the whole system operation, as well as management decisions to be taken by a VTS operator. Therefore, it is concluded that the operation should ensure the most effective functioning of technical facilities.

The article describes aspects of evaluation of quality, reliability of software regarding theoretical basis, methods, main tendencies and problems in this area.