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101.
A new method is introduced for the computation of hyperterminants. It is based on recurrence relations, and can also be used to compute the parameter derivatives of the hyperterminants. These parameter derivatives are needed in hyperasymptotic expansions in exceptional cases. Numerical illustrations and an application are included. 相似文献
102.
Hideaki Matsunaga 《Proceedings of the American Mathematical Society》2008,136(12):4305-4312
For a linear delay differential system with two coefficients and one delay, we establish some necessary and sufficient conditions on the asymptotic stability of the zero solution, which are composed of delay-dependent and delay-independent stability criteria. On the former criterion, the range of the delay is explicitly given.
103.
On the jump behavior of distributions and logarithmic averages 总被引:1,自引:0,他引:1
Jasson Vindas Ricardo Estrada 《Journal of Mathematical Analysis and Applications》2008,347(2):597-606
The jump behavior and symmetric jump behavior of distributions are studied. We give several formulas for the jump of distributions in terms of logarithmic averages, this is done in terms of Cesàro-logarithmic means of decompositions of the Fourier transform and in terms of logarithmic radial and angular local asymptotic behaviors of harmonic conjugate functions. Application to Fourier series are analyzed. In particular, we give formulas for jumps of periodic distributions in terms of Cesàro–Riesz logarithmic means and Abel–Poisson logarithmic means of conjugate Fourier series. 相似文献
104.
In a recent paper [P. Bates, A. Chmaj, A discrete convolution model for phase transition, Arch. Rational Mech. Anal. 150 (1999) 281-305], a discrete convolution model for Ising-like phase transition has been derived, and the existence, uniqueness of traveling waves and stability of stationary solution have been studied. This nonlocal model describes l2-gradient flow for a Helmholts free energy functional with general range interaction. In this paper, by using the comparison principle and the squeezing technique, we prove that the traveling wavefronts with nonzero speed is globally asymptotic stable with phase shift. 相似文献
105.
A mathematical model is proposed to study the role of supplementary self-renewable resource on species population in a two-patch habitat. It is assumed that the density of forest resource biomass is governed by the logistic equation in both the regions but with the different intrinsic growth rate but the same carrying capacity in the entire habitat. It is further assumed that the densities of species population is also governed by the generalized logistic equations in both the regions but with different growth rates and carrying capacities. It is shown that the steady state solutions are positive, monotonic and continuous under both reservoir and no-flux boundary conditions. The linear and non-linear asymptotic stability conditions of non-uniform steady state are compared with the case of the model with and without diffusion in a homogeneous habitat. 相似文献
106.
107.
Piotr W. Nowak 《Advances in Mathematics》2008,219(1):1-26
The isoperimetric profile of a discrete group was introduced by Vershik, however it is well defined only for a restrictive class amenable groups. We generalize the notion of isoperimetric profile beyond the world of amenable groups by defining isoperimetric profiles of amenable actions of finitely generated groups on compact topological spaces. This allows to extend the definition of the isoperimetric profile to all groups which are exact in such a way that for amenable groups it is equal to Vershik's isoperimetric profile. The main feature of our construction is that it preserves many of the properties known from the classical case. We use these results to compute exact asymptotics of the isoperimetric profiles for several classes of non-amenable groups. 相似文献
108.
Albrecht Bttcher Sergei M. Grudsky Egor A. Maksimenko 《Linear algebra and its applications》2008,429(1):346-366
The Szegö and Avram–Parter theorems give the limit of the arithmetic mean of the values of certain test functions at the eigenvalues of Hermitian Toeplitz matrices and the singular values of arbitrary Toeplitz matrices, respectively, as the matrix dimension goes to infinity. The question on whether these theorems are true whenever they make sense is essentially the question on whether they are valid for all continuous, nonnegative, and monotonously increasing test functions. We show that, surprisingly, the answer to this question is negative. On the other hand, we prove the two theorems in a general form which includes all versions known so far. 相似文献
109.
110.
Recently, a state-dependent change of measure for simulating overflows in the two-node tandem queue was proposed by Dupuis
et al. (Ann. Appl. Probab. 17(4):1306–1346, 2007), together with a proof of its asymptotic optimality. In the present paper, we present an alternative, shorter and simpler
proof. As a side result, we obtain interpretations for several of the quantities involved in the change of measure in terms
of likelihood ratios.
Part of this research has been funded by the Dutch BSIK/BRICKS project; part of this research was done while the first author
was visiting INRIA/IRISA, Rennes, France. 相似文献