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991.
The Markov properties of the solutions of Ito-Skorokhod stochastic functional-differential equations (SFDEs) with entire prehistory
are considered, the concept of a weak infinitesimal operator is introduced for a Markov process that is a solution of an SFDE,
and the strong solution of the SFDE is analyzed for stability.
Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 123–134, January–February 2009. 相似文献
992.
We propose a modification of the additive splitting algorithm to solve the convection-diffusion problem using an efficient
finite-difference scheme. The modification decreases the number of data exchanges and their amount during the numerical solution
of a system of multidimensional equations. Approximation, stability, and convergence are considered.
Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 100–107, January–February 2009. 相似文献
993.
The problem-solving time and the solution accuracy are expressed as functions of a parameter. An optimization problem of choosing
the parameter using a “time cost–solution accuracy” criterion is considered. A Pareto-optimal set of solutions is obtained.
The best value of the parameter is chosen by the ideal-point method.
Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 98–105, July–August 2009. 相似文献
994.
The key results in the standardization of system and software engineering in Ukraine are outlined and rationales of the national
standardization approaches in this field are presented. All the current national standards in software engineering are reviewed. 相似文献
995.
I. A. Boguslavskii O. V. Kruglyakova N. Ya. Miroshichev G. M. Tsimbalyuk 《Journal of Computer and Systems Sciences International》2009,48(3):333-344
The parameter identification problem for the nonlinear dynamic system of a sufficiently general form, in which the multipolynomial approximation algorithm processes measured data, is considered. To show the efficiency of the algorithm, an example of parameter identification for a nonlinear dynamic system with non-differentiable right-hand side is given and the identification problem for aerodynamic parameters of aircraft pitching motion is solved. 相似文献
996.
A. S. Bannikov 《Journal of Computer and Systems Sciences International》2009,48(4):527-532
A linear non-stationary conflict-interaction problem for controlled objects with n pursuers and m evaders with equal dynamical potency of each participant is considered. The objective of the pursuers is to capture all the evaders; the objective of the evaders is to avoid overtaking of at least one of them. Sufficient conditions for the global evasion problem solvability are stated. 相似文献
997.
E. L. Akim A. P. Astakhov R. V. Bakit’ko V. P. Pol’shchikov V. A. Stepan’yants A. G. Tuchin D. A. Tuchin V. S. Yaroshevskii 《Journal of Computer and Systems Sciences International》2009,48(2):295-312
An autonomous navigation system for near-Earth spacecraft is described; this system allows determination of the satellite orbit and prediction of its motion parameters. Radio navigation measurements of GLONASS and GPS satellite systems are used for this purpose. The autonomous navigation system is designated for operation on near-Earth orbits which do not go beyond the navigation areas of GLONASS and/or GPS and on orbits with large eccentricity whose apocenter is at a distance of 50–70 thousand km from the Earth’s surface. The developed methods and algorithms for orbit determination are based on the application of laws of motion dynamics of a spacecraft directly at processing primary phase measurements of the carrier frequency and code pseudo-range using an extended measurement base. Algorithms for determination of motion parameters of the spacecraft and results of simulation and operation of a model system are presented. The possibility of creation of an onboard autonomous navigation system with precision and reliability higher than those of the ground measuring complex is demonstrated. 相似文献
998.
V. V. Avetisyan S. R. Martirosyan 《Journal of Computer and Systems Sciences International》2009,48(5):814-826
An optimal guaranteed control problem for electromechanical manipulator with the goal of finding an immovable or mobile target
objects is considered. Unlike [1–6], as the optimality criterion, a functional taking into account power inputs of the light
source on the gripper of the manipulator is taken. The sought object is assumed to be detected if it falls into the light
circle with given illumination. The control algorithms of the gripper motion and corresponding laws of electric current variation
in the light source circuit providing the detection of both immovable and mobile sought object in a guaranteed time for minimal
light power inputs during the search are developed. The gain in light power inputs achieved for the proposed search algorithms
is estimated. 相似文献
999.
V. N. Fal’k 《Journal of Computer and Systems Sciences International》2009,48(1):78-83
FALGOL (Formal ALGOrithmic Language) is a fundamental theoretical model of high-level operational languages with unrestricted program object hierarchy. This model formalizes binding, assignment, substitution, and recursion; moreover, the principle of dynamic binding is implemented in the model in contrast to other formal systems of this sort, which makes FALGOL appropriate to specify the most difficultly formalized concepts in modern object programming languages. 相似文献
1000.
A. N. Zhirabok A. E. Shumsky 《Journal of Computer and Systems Sciences International》2009,48(4):559-566
The problem of fault accommodation in nonlinear dynamic systems is solved by constructing a control law that provides full decoupling with respect to fault effects. Existence conditions are found, and calculating relations are given for the control law. 相似文献