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The paper gives the analysis of existing systems of service-oriented architecture control, which allowed concluding that although the considered systems provide comprehensive facilities of service monitoring and users informing in various situations, they do not provide the management of service quality policies. Also, the main quality parameters for SOA systems, such as response time, maximum bandwidth, accessibility and reliability, were defined. The paper first proposed the method for monitoring QoS parameters for systems with service-oriented architecture on provider's side, which has two implementation modes - passive monitoring and active testing. The algorithms for selecting a particular service instance, which matches the specified quality parameters, were proposed. [ABSTRACT FROM AUTHOR]

Intermittent failures of REE (radio electronic equipment) are hard to predict, while they may lead to critical consequences. We propose the method, based on the theory of runs of random processes for predicting the parametric reliability of REE. This method allows predicting the duration of runs, their number and average duration of one run in the interval from 0 to T, on condition of the known three-dimensional random variable distribution law. The analytical and graphic dependencies for determining the parameters of the random process of change of REE defining parameter are given in the paper. The proposed method allows taking into account intermittent failures and predicting reliability for stationary and non-stationary processes. In addition, as a result of some simplifications, predicting is carried out with the known regression of expected value and variance, as well as the known random process distribution law. The main advantage of the developed method is that it allows predicting the reliability of radio electronic equipment both in the case of the stationary process, and in the cases of the process with periodic component and quasideterministic random process [ABSTRACT FROM AUTHOR]

The analysis and the classification of indicators of quantitative evaluation of reliability of a special communication system using the systemic approach in their study are proposed. The features of element and structural reliability of special communication systems were considered. It is shown that they belong to complex technical systems. Therefore, to determine and study their reliability indicators, simulation and systemic approach should be used. Analysis of the composition of the special communication system and interaction between its elements shows that the reliability property, which lies in the ability to provide communication with preservation in time of performance indicators values, established by specifications and technical documentation, is supported by technical communication support subsystem with the performance of all types of repair, maintenance and provision with operational materials and consumables. Traditionally, the availability factor, which is the serviceability probability of all system elements and the availability of all communication directions for the full operation, is used as the main reliability indicator of the special communication system. However, for special communication systems with more objective characteristic there is the probability of system availability to transfer information between subscribers (communication nodes) at least in one communication direction that in the literature on reliability theory is called the connectivity probability or serviceability probability of at least one of the possible communication directions. The paper shows that the availability factor is less than serviceability probability. The equality occurs if each element of the special communication system is used only in one direction and only once without other communication directions [ABSTRACT FROM AUTHOR]

The problem of increasing the durability of V-belt transmissions of mechanical presses is considered in the paper. The issue of determining the factors that influence durability and ways of its improvement is set. Based on fatigue strength provisions it was found that transmission durability is determined primarily by the largest stress value in transmission sides and the number of belt runs. The major way of increasing the durability is ensuring the minimum initial tension, sufficient for design load transmission, and its systematic control. Durability of belts is improved by increasing transmission ratio, reducing the number of runs, increasing spacing on centers. Durability of drive as a whole is determined by reliability of separate belts, their quantity and condition of drive failure as a system. Increasing the number of transmission belts improves durability of transmission as a whole only with the use of hot standby. The research results can be used in designing belt transmissions of other technological and transport machines for increasing their performance standards. [ABSTRACT FROM AUTHOR]

The problem of increasing the durability of V-belt transmissions of mechanical presses is considered in the paper. The issue of determining the factors that influence durability and ways of its improvement is set. Based on fatigue strength provisions it was found that transmission durability is determined primarily by the largest stress value in transmission sides and the number of belt runs. The major way of increasing the durability is ensuring the minimum initial tension, sufficient for design load transmission, and its systematic control. Durability of belts is improved by increasing transmission ratio, reducing the number of runs, increasing spacing on centers. Durability of drive as a whole is determined by reliability of separate belts, their quantity and condition of drive failure as a system. Increasing the number of transmission belts improves durability of transmission as a whole only with the use of hot standby. The research results can be used in designing belt transmissions of other technological and transport machines for increasing their performance standards. [ABSTRACT FROM AUTHOR]

The features of using computer-aided design systems and modern technologies in the automobile industry are considered in the paper. Methods of using modern information technologies and systems for modeling the structure of internal combustion engines are proposed. The advantages of combining CAD and CAM systems in particular software products are emphasized. Approaches to using Delcam plc products are justified, the sequence of design for ensuring an optimum design solution is specified. The requirements and risk analysis for designing internal combustion engines are given. Special attention was paid to the problem of geometric calculations of the crank mechanism parts when modeling cranks and pistons. An algorithm for constructing the 3D-model of internal combustion engine prototype with increased capacity, without changing the body size, is considered. Design algorithm consists of four stages, each of them determines the final shape of all construction parts. [ABSTRACT FROM AUTHOR]