Begell House Inc.
Journal of Automation and Information Sciences
JAI(S)
1064-2315
49
2
2017
Optimal Stabilization of the Earth Artificial Satellite with Redundant Fly-Wheels under Uncertain Conditions
1-15
10.1615/JAutomatInfScien.v49.i2.10
Sergey M.
Onishchenko
Institute of Mathematics of National Academy of Sciences of Ukraine, Kiev
optimal stabilization
observation problem
redundant fly-wheels
uncertain conditions
Consideration is given to the observation problem of the state vector errors of SC in its spherical motion in the stationary circular orbit using the information of three-component magnetometer (the navigation task of determining the satellite position is assumed to be solved beyond the scope of this work). The application of the rigid synthesis method of nonlinear stabilization systems ensures the uniform asymptotic stability of homogeneous error observation system and the stable observer construction under uncertain conditions. Therewith the quality of satellite stabilization in the orientation mode is on average by 28% (by results of mathematical simulation) worse than that of its stabilization with the controller using precise values of its angular velocity deviations from the nominal values.
Investigation of Parallel Algorithms for Solving Problems of Convection Diffusion on the Basis of Splitting Schemes
16-30
10.1615/JAutomatInfScien.v49.i2.20
Anatoliy V.
Gladky
V.M. Glushkov Institute of Cybernetics of National Academy of Sciences of Ukraine, Kiev
Vsevolod A.
Bohaienko
V.M. Glushkov Institute of Cybernetics of National Academy of Sciences of Ukraine, Kiev
three-dimensional nonstationary equation
convective diffusion
technique of geometrical splitting
difference scheme of running computation
approximation
stability
monotony
cluster systems
theoretical estimates of rate
numerical experiments
For solving of three-dimensional nonstationary equation of convective diffusion an approach on the basis of technique of geometrical splitting with further solving of the obtained one-dimensional problems by means of difference schemes of running computation is suggested. For the suggested difference schemes of splitting the questions of approximation, stability and monotony are investigated. Three schemes of data distribution on implementation of running computations algorithms on cluster systems are considered. Theoretical estimates of their rate are obtained, which were compared with results of numerical experiments.
Construction of Stability Domain of Digital Linear Systems in Space of Parameters Using Method of Discrete D-Partition
31-42
10.1615/JAutomatInfScien.v49.i2.30
Leonid T.
Movchan
Ivan Pulyui Ternopol National Technical
University, Ternopol
Sergey L.
Movchan
Consulting center "BIZON", Ternopol, Ukraine
stability domain
digital linear systems
a space of two parameters
D-partition method
Consideration is given to the problem of constructing stability domain of linear digital systems in a space of two parameters nonlinearly entering coefficients of characteristic equation. The new algorithm for determining boundary points of stability domain by enumeration of only one parameter in uniquely determined direction without verification of system stability or instability at these points is proposed. Simplified algorithm for stability domain determination significantly reduces the volume and time of calculations required for solving this problem. Correctness of results is guaranteed by employing D-partition method.
On Formulation of Problems of Precise Decomposition of Linear Mathematical Models
43-49
10.1615/JAutomatInfScien.v49.i2.40
Yuriy N.
Bazilevich
Pridneprovskaya State Academy of Civil
Engineering and Architecture, Dnepr
Irina A.
Kostyushko
Pridneprovskaya State Academy of Civil
Engineering and Architecture, Dnepr
linear mathematical models
precise decomposition
controlled systems
rectangular matrices coefficients
symmetry groups
hidden symmetry
hierarchical decomposition
Various approaches to the problem of decomposition and mathematical models that allow one to use it effectively are described. Main attention is being paid to decomposition of the systems of linear equations described by several matrices of coefficients. A brief description of the literature on decoupling is given.
Mathematical Models and Methods of the Analysis of Computer Networks of Control of Power Supply of Railways Traction Substations
50-60
10.1615/JAutomatInfScien.v49.i2.50
Alexander I.
Stasiuk
State Economy and Technology University
of Transport, Kiev
Lidiya L.
Goncharova
State Economy and Technology University
of Transport, Kiev
railway traffic
computer network
power supply control
safety
traction substation
intellectualization
indicators calculating
topology
network graph
The analysis of the evolution of power supply networks of railways has showed that the solution of complex optimization problems of power consumption and improvement of railway traffic safety is possible due to intellectualization of electric power supply processes. The computer network of power supply control at the level of traction substations, which adequately displays its topology and the graph of network is offered. On the basis of differential transformations a mathematical model of computer architecture of control of traction substations power supply, as well as the methods of determining in analytical form the set of probability values of the states of the graph nodes of computer network and criteria for calculating such indicators: throughput of the nodes, the average number of requests that are processed, and the number of failures of service calls, are developed.
Perfection of Control Loop of Gas Turbine Power of Cogeneration Power Installation under Fuel Quality Variation
61-69
10.1615/JAutomatInfScien.v49.i2.60
Olga S.
Tarakhtii
Odessa National Polytechnic University,
Odessa
low heat of combustion
cogeneration power installation
analysis on dynamic characteristics
loop of power control
supplementary control signal
gas temperature on output
computer modeling
Analysis of influence of variation of low heat of combustion on dynamic characteristics of cogeneration power installation is done. The loop of power control of gas-turbine installation by means of introduction of supplementary signal on the basis of gas temperature on output of combustion chamber. Results of computer modeling are presented.
Estimation of Credit Borrowers Solvency Using Fuzzy Logic
70-84
10.1615/JAutomatInfScien.v49.i2.70
Ramin Rza ogly
Rzayev
Institute of Control Systems of National
Academy of Sciences of Azerbaijan, Baku
(Azerbaijan)
Aliaga Alekper ogly
Aliyev
Institute of Control Systems of National
Academy of Sciences of Azerbaijan, Baku
(Azerbaijan)
natural persons creditworthiness
estimates
fuzzy logic
conditions of uncertainty
aggregating
key indicators assessments
rankings of declared borrowers
An alternative approach to assessing the creditworthiness of natural persons is proposed, based on the use of fuzzy decision-making methods in conditions of uncertainty. As an alternative, arbitrarily five borrowers are chosen, which differ in their data on key indicators of solvency. After obtained results of calculation by two methods there are implemented rankings of declared borrowers and identified the most solvent of them.