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961.
An abstract version of Besov spaces is introduced by using the resolvent of nonnegative operators. Interpolation inequalities with respect to abstract Besov spaces and generalized Lorentz spaces are obtained. These inequalities provide a generalization of Sobolev inequalities of logarithmic type. Uniqueness problems to abstract semilinear evolution equations are also discussed (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
962.
Jeehoon Park 《Journal of Number Theory》2010,130(11):2610-2627
We study a special case of the Gross-Stark conjecture (Gross, 1981 [Gr]), namely over genus fields. Based on the same idea we provide evidence of the rationality conjecture of the elliptic units for real quadratic fields over genus fields, which is a refinement of the Gross-Stark conjecture given by Darmon and Dasgupta (2006) [DD]. Then a relationship between these units and the Fourier coefficients of p-adic Eisenstein series of half-integral weight is explained. 相似文献
963.
In Korea, many forms of credit guarantees have been issued to fund small and medium enterprises (SMEs) with a high degree of growth potential in technology. However, a high default rate among funded SMEs has been reported. In order to effectively manage such governmental funds, it is important to develop an accurate scoring model for selecting promising SMEs. This paper provides a support vector machines (SVM) model to predict the default of funded SMEs, considering various input variables such as financial ratios, economic indicators, and technology evaluation factors. The results show that the accuracy performance of the SVM model is better than that of back-propagation neural networks (BPNs) and logistic regression. It is expected that the proposed model can be applied to a wide range of technology evaluation and loan or investment decisions for technology-based SMEs. 相似文献
964.
We present an H1‐Galerkin mixed finite element method for a nonlinear parabolic equation, which models a compressible fluid flow process in subsurface porous media. The method possesses the advantages of mixed finite element methods while avoiding directly inverting the permeability tensor, which is important especially in a low permeability zone. We conducted theoretical analysis to study the existence and uniqueness of the numerical solutions of the scheme and prove an optimal‐order error estimate for the method. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
965.
966.
Robert Hable 《International Journal of Approximate Reasoning》2010,51(9):1114-1128
The article considers estimating a parameter θ in an imprecise probability model which consists of coherent upper previsions . After the definition of a minimum distance estimator in this setup and a summarization of its main properties, the focus lies on applications. It is shown that approximate minimum distances on the discretized sample space can be calculated by linear programming. After a discussion of some computational aspects, the estimator is applied in a simulation study consisting of two different models. Finally, the estimator is applied on a real data set in a linear regression model. 相似文献
967.
杜兴华 《数学的实践与认识》2010,40(13)
利用多项式的完全判别系统和初等积分法求出了Maccari's方程组的许多新的精确行波解.此方法与其它方法相比更简洁. 相似文献
968.
关于Steiner问题的一个注记——连接五点之最小网络的一种寻优方案 总被引:2,自引:0,他引:2
本文讨论如何寻找连接平面上五个给定点的最小网络这一问题.通过发展越民义证明Pollack在1978年所给出的一个关于寻找连接平面上四个给定点的最小网络的重要结论的方法,我们给出了一个采用简单几何作图方法快速求解该问题的方案. 相似文献
969.
GALAKTIONV V.A. 《偏微分方程(英文版)》2010,(2):105-146
Blow-up behaviour for the fourth-order quasilinear porous medium equation with source,ut=-(|u|^nu)xxxx+|u|^p-1u in R×R+,where n 〉 0, p 〉 1, is studied. Countable and finite families of similarity blow-up patterns of the form us(x,t)=(T-t)^-1/p-1f(y),where y=x/(T-t)^β' β=p-(n+1)/4(p-1),which blow-up as t → T^- 〈∞ are described. These solutions explain key features of regional (for p = n+1), single point (for p 〉 n+1), and global (for p ∈ (1,n+1))blowup. The concepts and various variational, bifurcation, and numerical approaches for revealing the structure and multiplicities of such blow-up patterns are presented. 相似文献
970.
Vladimir I. Bogachev Nicolai V. Krylov Michael Rckner 《Journal de Mathématiques Pures et Appliquées》2006,85(6):743-757
We consider elliptic equations of the form L*μ=ν for measures on . The membership of solutions in the Sobolev classes is established under appropriate conditions on the coefficients of L. Bounds of the form (x)CΦ(x)−1 for the corresponding densities are obtained. 相似文献