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171.
Generalized dimensions,entropies, and Liapunov exponents from the pressure function for strange sets
For conformal mixing repellers such as Julia sets and nonlinear one-dimensional Cantor sets, we connect the pressure of a smooth transformation on the repeller with its generalized dimensions, entropies, and Liapunov exponents computed with respect to a set of equilibrium Gibbs measures. This allows us to compute the pressure by means of simple numerical algorithms. Our results are then extended to axiom-A attractors and to a nonhyperbolic invariant set of the line. In this last case, we show that a first-order phase transition appears in the pressure. 相似文献
172.
Optimal stopping,exponential utility,and linear programming 总被引:1,自引:0,他引:1
This paper uses linear programming to compute an optimal policy for a stopping problem whose utility function is exponential. This is done by transforming the problem into an equivalent one having additive utility and nonnegative (not necessarily substochastic) transition matrices.Research was supported by NSF Grant ENG 76-15599. 相似文献
173.
Todd Cochrane Christopher Pinner 《Proceedings of the American Mathematical Society》2005,133(2):313-320
For a sparse polynomial , with and , we show that
thus improving upon a bound of Mordell. Analogous results are obtained for Laurent polynomials and for mixed exponential sums.
thus improving upon a bound of Mordell. Analogous results are obtained for Laurent polynomials and for mixed exponential sums.
174.
Frédéric Bernard 《Journal of Mathematical Analysis and Applications》2005,303(1):1-14
This paper studies the prox-regularity concept for functions in the general context of Hilbert space. In particular, a subdifferential characterization is established as well as several other properties. It is also shown that the Moreau envelopes of such functions are continuously differentiable. 相似文献
175.
Zdzis?aw?Brze?niak Bohdan?Maslowski Jan?SeidlerEmail author 《Probability Theory and Related Fields》2005,132(1):119-149
An extensible beam equation with a stochastic force of a white noise type is studied, Lyapunov functions techniques being used to prove existence of global mild solutions and asymptotic stability of the zero solution.This research was supported in part by the GA R Grants no. 201/98/1454, 201/01/1197 and by a Royal Society grant 相似文献
176.
Sums of Five Almost Equal Prime Squares 总被引:5,自引:0,他引:5
Claus BAUER 《数学学报(英文版)》2005,21(4):833-840
Let Pi, 1≤i≤5, be prime numbers. It is proved that every integer N that satisfies N=5 (mod 24) can be written as N=p1^2+p2^2+P3^2+p4^2 +p5^2, where │√N5-Pi│≤N^1/2-19/850+∈. 相似文献
177.
Leonid Berezansky Elena Braverman 《Journal of Mathematical Analysis and Applications》2006,314(2):391-411
New explicit conditions of exponential stability are obtained for the nonautonomous equation with several delays
178.
J. Ignacio Tello 《Journal of Mathematical Analysis and Applications》2006,324(1):381-396
We consider the Cauchy problem
179.
In this Letter, exponential synchronization of a complex network with nonidentical time-delayed dynamical nodes is considered. Two effective control schemes are proposed to drive the network to synchronize globally exponentially onto any smooth goal dynamics. By applying open-loop control to all nodes and adding some intermittent controllers to partial nodes, some simple criteria for exponential synchronization of such network are established. Meanwhile, a pinning scheme deciding which nodes need to be pinned and a simply approximate formula for estimating the least number of pinned nodes are also provided. By introducing impulsive effects to the open-loop controlled network, another synchronization scheme is developed for the network with nonidentical time-delayed dynamical nodes, and an estimate of the upper bound of impulsive intervals ensuring global exponential stability of the synchronization process is also given. Numerical simulations are presented finally to demonstrate the effectiveness of the theoretical results. 相似文献
180.
Francis N. Castro Robin Chapman Luis A. Medina L. Brehsner Sepúlveda 《Discrete Mathematics》2018,341(7):1915-1931
Rotation symmetric Boolean functions are invariant under circular translation of indices. These functions have very rich cryptographic properties and have been used in different cryptosystems. Recently, Thomas Cusick proved that exponential sums of rotation symmetric Boolean functions satisfy homogeneous linear recurrences with integer coefficients. In this work, a generalization of this result is proved over any Galois field. That is, exponential sums over Galois fields of some rotation symmetric polynomials satisfy linear recurrences with integer coefficients. In the particular case of , an elementary method is used to obtain explicit recurrences for exponential sums of some of these functions. The concept of trapezoid Boolean function is also introduced and it is showed that the linear recurrences that exponential sums of trapezoid Boolean functions satisfy are the same as the ones satisfied by exponential sums of the corresponding rotations symmetric Boolean functions. Finally, it is proved that exponential sums of trapezoid and symmetric polynomials also satisfy linear recurrences with integer coefficients over any Galois field . Moreover, the Discrete Fourier Transform matrix and some Complex Hadamard matrices appear as examples in some of our explicit formulas of these recurrences. 相似文献