Method of active loaded reservation structure synthesis based on optimization of increments of multiplicative faultlessness criteria

Аuthors

Usovik I. V.^1*, Grishin V. M.^2**

1. Federal State Institution “Federal Scientific Center Scientific Research Institute for System Analysis of the Russian Academy of Sciences”, Nachimovskiy prosp., Moscow, 117218, Russia
2. Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia

*e-mail: usovikiv@gmail.com
**e-mail: Vyacheslav.Grishin@gmail.ru

Abstract

This paper is devoted to the increase of system reliability in aerospace field. It is focused on the search of new methods for synthesis of reservation systems structures, which consist of a large number of elements. The new method for finding optimal structure of active loaded block reservation of space-aviation systems and their subsystems, which provide maximum reliability, is considered in this paper.
Both active and passive (constant) reservations consume resources of backup elements. The application of active loaded reservation is often explained by the fact that parameters of the system do not change in case of failure. For example, in cases when parameters of space control systems exceed acceptable values this may cause not only unacceptable changes of time and frequency characteristics, but also a loss of their stability. Moreover the loaded active reservation provides a constant readiness for the work of reserve elements, which is very important for aviation.
The basis of this method is the creation of branches of the solution-search tree for synthesis task with the help of optimal structure from the previous step. At each step the branches of the tree are formed in such a way, that they keep properties of structures from previous branches and partially properties of adjacent ones. This method allows to develop a tree only in direction of the true solution and not to consider the other branches. The choice of optimal reservation structure of current step is made only from the scope of branches, which were obtained from optimal structure at the previous step.
This paper considers properties of the proposed method, evaluates its computational complexity in comparison with the wave method and enumerating technique. The method is easy to use and it does not require creation of cumbersome model of graphs such as Deijkstra and wave method. Computational complexity of the method does not increase the polynomial of degree two of the system size. The number of elements in the main junction of unreserved system is used as the size of the system.
Sizes of all blocks and the number of blocks in the reserved system are the optimized parameters. The given parameters of the system are: size (the number of elements in the system), reliability factors of elements in the system, reliability factor of switches, multiplication factor.
Application examples of method for finding optimal structures of systems reservation with various characteristics are given in this paper.
The method can be used for increase of large systems reliability and their large-size subsystems.

Keywords:

reliability factors, sudden refuse, active load reservation, extremum, block reservation, optimization, synthesis of reservation structures, optimal solution search tree

References

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