In the article experimental survey results of planetary roller screw drive for usage in high precision parallel structure mechanisms for space application are considered. The drive was developed in Academician M.F. Reshetnev Information Satellite System. Roller screw is perspective type of precision linear drives which excels in several characteristics extensively used in modern time ball screws. Ground tests conducting methodology, tests scheme of the developed roller screw are described. Key parameters of analyzed precision linear drive such as: transmission accuracy, repeatability, axial stiffness and operating lifetime are presented.
The paper presents an analysis of nonparametric methods for assessing the comparative efficiency of agro-industrial enterprises. The authors analyzed Data Envelopment Analysis, Free Disposal Hull Analysis and Productivity Index. The most important characteristics of the models are highlighted, which are used to compare the methods. The preference was given to the DEA method, since the other described methods and their modifications do not allow taking into account the factors influencing the efficiency of agricultural enterprises. In particular, the factor of the territorial location of the enterprise. But it is the climatic zone of the location of the enterprise that has a significant impact on the efficiency of agricultural activities. When implementing the assessment method, it is necessary to take into account the fact that climatic conditions, depending on the geographical location, are always different.
The article considers the possibility of organizing a single information space on the basis of a modernized document management system within the technically complex products life cycle, which involves the processing of a large amount of various information. The attention is focused on the fact that in the existing automation systems of various processes for creating products at various stages of the life cycle, the availability, connectivity and consistent storage of data in the corresponding accounting systems are not ensured. A method for organizing data on a product is proposed, and on its basis a tool for implementing a single source in the form of a document management system describes the advantages of its application when integrated into a single information space.
As a tool to reduce the risks of innovation at the machine-building enterprises the authors suggest a new methodology aimed at point-based assessment of innovation risks. However, the experts are more likely to give interval estimates when assessing the risks of innovation. To work with interval estimates, a new software system was developed. The authors suggest using a market model that assumes a division of risks into systematic and non-systematic and allows to take into account the effect of diversification of the innovative portfolio of the machine-building enterprise. The steps of the methodology and its approbation on the data on innovative projects of one of Russian Federal Space Agency (Roskosmos) enterprises are presented in the paper.
The article deals with the methods of transfer of thermal energy of electric heaters to the nodes and devices of non-pressurized spacecraft, which are part of the spacecraft in the target orbits in the conditions of regular use. The basic technical characteristics of perspective electric heaters for operating conditions are developed, the model of regular position of electric heaters allowing to define ways of increase of efficiency and efficiency of electric heaters is developed. The main results of the development of flexible film electric heaters various design using materials produced by the domestic industry and manufactured using a new method based on the method of photolithography and etching the resistive layer, allowing to implement new functionality and improve efficiency of electric heaters, the experiments confirming the calculations in conditions simulating operational influences on electric heaters. The using of flexible film electric heaters increased efficiency in the existing and future spacecraft can improve the efficiency of the thermal control system as a whole, improves manufacturability.
The article proposes an original method for decomposition of fault-tolerant multiversion systems based on multi-attribute analysis. Decomposition into functional subsystems is carried out taking into account the generality of functions performed by software modules. In this work, the attribute of the importance of functions is determined based on the general function of the unmanned aerial vehicle and the set of tasks that it must perform. The division of software modules into types allows you to determine possible ways to improve reliability that are applicable to them. These are, for example, multi-version programming, recovery blocks, t/(n-1)-variant programming.
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