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991.
We consider the quotient set of the set of nondegenerate affinor fields with respect to the action of the group of nowhere vanishing functions. This set is endowed with a structure of infinite-dimensional Lie group. On this Lie group, we construct an object of linear connection with respect to which all left-invariant vector fields are covariantly constant (the Cartan connection).  相似文献   
992.
993.
This paper is devoted to exact and approximate methods (first of all, direct ones) for the solution of integro-operational equations. Themost attention is paid to the theoretical substantiation of the collocation method for the solution of the mentioned equations within the general theory of approximate methods developed by L. V. Kantorovich.  相似文献   
994.
We discuss here a new general linear algebraic method (both model and algorithm) for describing and generating (among others) minimal reactions and also minimal mechanisms in stoichiometry, or dimensionless groups in physics as well. (Further applications in process network syntheses will be discussed in .) With some minor modifications of the input this method can be extended for several related questions: for generating direct and overall reactions, direct (steady state) mechanisms, for finding the possible resulting (overall) reactions among all possible mechanisms, etc.Computational results in section 4 show the speed of our algorithm.We give also mathematical background and results in sections 3, 5 and 6. However, we do not restrict ourselves to mathematics only, we also talk on the language of chemistry, too.The theoretical results in sections 3.2, 3.3, 5 and the computational examples in section 4 are completely new, further theoretical results will appear in and in .  相似文献   
995.
We obtain sufficient conditions for the existence of a nonanticipating control for linear systems with stationary random parameters. We consider the case of a bounded control and an arbitrary number of system states. We estimate the probability that the system is nonanticipatingly locally controllable on a fixed time interval. We formulate the main assertions in terms of Lyapunov functions, choosing the latter in the class of piecewise continuously differentiable functions.  相似文献   
996.
This paper investigates robust filter design for linear discrete-time impulsive systems with uncertainty under H∞ performance. First, an impulsive linear filter and a robust H∞ filtering problem are introduced for a discrete-time impulsive systems. Then,a sufficient condition of asymptotical stability and H∞ performance for the filtering error systems are provided by the discrete-time Lyapunov function method. The filter gains can be obtained by solving a set of linear matrix inequalities (LMIs). Finally, a numerical example is presented to show effectiveness of the obtained result.  相似文献   
997.
We show how conditionally negative definite functions on spheres coupled with strictly completely monotone functions (or functions whose derivative is strictly completely monotone) can be used for Hermite interpolation. The classes of functions thus obtained have the advantage over the strictly positive definite functions studied in [17] that closed form representations (as opposed to series expansions) are readily available. Furthermore, our functions include the historically significant spherical multiquadrics. Numerical results are also presented. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
998.
Natasha Flyer Many types of radial basis functions (RBFs) are global in termsof having large magnitude across the entire domain. Yet, incontrast, e.g. with expansions in orthogonal polynomials, RBFexpansions exhibit a strong property of locality with regardto their coefficients. That is, changing a single data valuemainly affects the coefficients of the RBFs which are centredin the immediate vicinity of that data location. This localityfeature can be advantageous in the development of fast and well-conditionediterative RBF algorithms. With this motivation, we employ hereboth analytical and numerical techniques to derive the decayrates of the expansion coefficients for cardinal data, in both1D and 2D. Furthermore, we explore how these rates vary in theinteresting high-accuracy limit of increasingly flat RBFs.  相似文献   
999.
Let F be a family of mermorphic functions in a domain D, and let a, b, c be complex numbers, a ≠ b. If for each f ∈ F, the zeros of f-c are of multiplicity ≥ k + 1, and -↑Ef(k)(a) belong to -↑Ef (a), -↑Ef(k)(b)belong to -↑Ef (b), then F is normal in D.  相似文献   
1000.
We study some combinatorial properties of Tetris-like games by using Schützenberger methodology and probability generating functions. We prove that every Tetris-like game is equivalent to a finite state automaton and propose a straight foward algorithm to transform a Tetris-like game into its corresponding automaton. In this way, we can study the average number of pieces inserted during a game and the average score as a function of the player's ability and the pieces extrusion.  相似文献   
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