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981.
Cone-valued Lyapunov functions and stability for impulsive functional differential equations 总被引:1,自引:0,他引:1
The stability criteria in terms of two measures for impulsive functional differential equations are established via cone-valued Lyapunov functions and Razumikhin technique. The stability can be deduced from the (Q0,Q)-stability of comparison impulsive differential equations. An example is given to illustrate the advantages of the results obtained. 相似文献
982.
A. Alvino 《Annali di Matematica Pura ed Applicata》2008,187(2):237-249
In the theory of linear elliptic problems with data not belonging to H ?1 two cases can be distinguished. When the right hand side in the equation is a summable function we point out that the a priori estimates can be attained very quickly by symmetrization methods. On the other side, when the datum includes a distributional term, different and subtler tools have to be used. We deal with an equation in the plane, whose right hand side is a functional on a space of Hölder continuous functions with a suitable exponent. We obtain a priori bounds via duality arguments; these, in addition, show Serrin pathological solution (see Serrin in Ann. Scuola Norm. Sup. Pisa 18(3), 385–387, 1964) in its true light. 相似文献
983.
Andrew Bakan 《Journal of Mathematical Analysis and Applications》2008,339(1):197-216
For the sets , 1?p<∞, of positive finite Borel measures μ on the real axis with the set of algebraic polynomials P dense in Lp(R,dμ), we establish a majorization principle of their “boundaries,” i.e. for every there exists such that dμ/dν?1. A corresponding principle holds for the sets , p>0, of non-negative upper semi-continuous on R functions (weights) w such that P is dense in the space : For every there exists such that w?ω. 相似文献
984.
Joaquín Motos María Jesús Planells César F. Talavera 《Journal of Mathematical Analysis and Applications》2008,338(1):162-174
It is proved that the Hörmander and spaces (Ω1⊂Rn, Ω2⊂Rm open sets, 1?p<∞, ki Beurling-Björck weights, k=k1⊗k2) are isomorphic whereas the iterated spaces and are not if 1<p≠q<∞. A similar result for weighted Lp-spaces of entire analytic functions is also obtained. Finally a result on iterated Besov spaces is given: and are not isomorphic when 1<q≠2<∞. 相似文献
985.
Mingjin Wang 《Journal of Mathematical Analysis and Applications》2008,341(2):1487-1494
In this paper, we use the Andrews-Askey integral and the q-Chu-Vandermonde formula to derive a more general integral formula. Applications of the new integral formula are also given, which include to derive the q-Pfaff-Saalschütz formula and the terminating Sears's transformation formula. 相似文献
986.
On solutions of a common generalization of the Go?a?b-Schinzel equation and of the addition formulae
Anna Mureńko 《Journal of Mathematical Analysis and Applications》2008,341(2):1236-1240
Under some additional assumptions we determine solutions of the equation
f(x+M(f(x))y)=f(x)○f(y), 相似文献
987.
A Liouville-Green (WKB) asymptotic approximation theory is developed for some classes of linear second-order difference equations in Banach algebras. The special case of linear matrix difference equations (or, equivalently, of second-order systems) is emphasized. Rigorous and explicitly computable bounds for the error terms are obtained, and this when both, the sequence index and some parameter that may enter the coefficients, go to infinity. A simple application is made to orthogonal matrix polynomials in the Nevai class. 相似文献
988.
Vakhid A. Mamedov Dina F. Saifina Aidar T. Gubaidullin Alina F. Saifina Il’dar Kh. Rizvanov 《Tetrahedron letters》2008,49(43):6231-6233
A highly efficient one-step and versatile method for the synthesis of 2-(indolizin-2-yl)benzimidazoles has been developed on the basis of the novel ring contraction of 3-arylchloromethyl- and alkylchloromethylquinoxalin-2-ones with α-picoline. 相似文献
989.
Guang-hui Cai 《Journal of mathematical chemistry》2008,43(1):375-385
Consider the partly linear regression model Y = xβ + g(t) + e where the explanatory x is erroneously measured, and both t and the response Y are measured exactly, the random error e is ρ−-mixing. Let be a surrogate variable observed instead of the true x in the primary survey data. Assume that in addition to the primary data set containing N observations of , which is ρ−-mixing data sets, an independent validation data containing n observations of is available. The exact observations on x may be obtained by some expensive or diffcult procedures for only a small subset of subjects enrolled in the study. In this
paper, inspired by Berberan-Santos et al. [J. Math. Chem. 37 (2005)101], a semiparametric method with the primary data is
employed to obtain the estimators of β and g(·) based on the least squares criterion with the help of validata. The proposed estimators are proved to be strongly consistent.
相似文献
990.
By use of Löwdin and Guseinov relations for the radial and angular part of two-center overlap integrals, respectively, the computer calculations of overlap integrals over Slater type orbitals (STOs) in molecular coordinate system are performed. The results of calculations are valid for arbitrary principal quantum numbers, screening constants and location of STOs. Excellent agreement with benchmark results and stability of the technique are demonstrated. 相似文献