排序方式: 共有44条查询结果,搜索用时 15 毫秒
21.
郑红 《南昌大学学报(理科版)》2005,29(2):1
以Hardy空间函数为系数的被限制到方程式的(0,1)形式标准解算子通过用Szeg核的积分算子表示,证明了在单位球上以Hardy空间函数为系数的被限制到方程式的(0,1)形式标准解算子不是Hilbert-Schmidt算子。在单位圆盘上相应的算子是Hilbert-Schmidt算子。 相似文献
22.
In this paper, we show that a number of known fixed point theorems for the Fan-Browder type maps or acyclic maps defined on (subsets of) hyperconvex metric spaces are simple consequences of the previously known theorems for corresponding maps defined on generalized convex spaces. 相似文献
23.
E.X.L. de Andrade 《Journal of Mathematical Analysis and Applications》2007,330(1):114-132
We consider a connection that exists between orthogonal polynomials associated with positive measures on the real line and orthogonal Laurent polynomials associated with strong measures of the class S3[0,β,b]. Examples are given to illustrate the main contribution in this paper. 相似文献
24.
Szeg? type polynomials with respect to a linear functional M for which the moments M[tn]=μ−n are all complex, μ−n=μn and Dn≠0 for n?0, are considered. Here, Dn are the associated Toeplitz determinants. Para-orthogonal polynomials are also studied without relying on any integral representation. Relation between the Toeplitz determinants of two different types of moment functionals are given. Starting from the existence of polynomials similar to para-orthogonal polynomials, sufficient conditions for the existence of Szeg? type polynomials are also given. Examples are provided to justify the results. 相似文献
25.
Leonid Golinskii 《Proceedings of the American Mathematical Society》2003,131(6):1771-1776
Measures on the unit circle and orthogonal polynomials are completely determined by their reflection coefficients through the Szego recurrences. We find the conditions on the reflection coefficients which provide the lack of a mass point at . We show that the result is sharp in a sense. 相似文献
26.
Pre-Bötzinger复合体是兴奋性耦合的神经元网络,通过产生复杂的放电节律和节律模式的同步转迁参与调控呼吸节律.本文选用复杂簇和峰放电节律的单神经元数学模型构建复合体模型,仿真了与生物学实验相关的多类同步节律模式及其复杂转迁历程,并利用快慢变量分离揭示了相应的分岔机制.当初值相同时,随着兴奋性耦合强度的增加,复合体模型依次表现出完全同步的“fold/homoclinic”,“subHopf/subHopf”簇放电和周期1峰放电.当初值不同时,随耦合强度增加,表现为由“fold/homoclinic”,到“fold/fold limit cycle”、到“subHopf/subHopf”与“fold/fold limit cycle”的混合簇放电、再到“subHopf/subHopf”簇放电的相位同步转迁,最后到反相同步周期1峰放电.完全(同相)同步和反相同步的周期1节律表现出了不同分岔机制.反相峰同步行为给出了与强兴奋性耦合容易诱发同相同步这一传统观念不同的新示例.研究结果给出了preBötzinger复合体的从簇到峰放电节律的同步转迁规律及复杂分岔机制,反常同步行为丰富了非线性动力学的内涵. 相似文献
27.
Jacob S. Christiansen 《Advances in Mathematics》2012,229(2):1180-1204
In this paper, we generalize Szeg?'s theorem for orthogonal polynomials on the real line to infinite gap sets of Parreau–Widom type. This notion includes Cantor sets of positive measure. The Szeg? condition involves the equilibrium measure which in turn is absolutely continuous. Our approach builds on a canonical factorization of the M-function and the covering space formalism of Sodin–Yuditskii. 相似文献
28.
Kenneth D. Koenig 《Journal of Geometric Analysis》2009,19(1):81-86
We show that the difference between the Bergman and Szegö projections on a smooth, bounded planar domain gains a derivative in the L p -Sobolev and Lipschitz spaces. 相似文献
29.
Szego quadrature rules are discretization methods for approximating integrals of the form . This paper presents a new class of discretization methods, which we refer to as anti-Szego quadrature rules. Anti-Szego rules can be used to estimate the error in Szego quadrature rules: under suitable conditions, pairs of associated Szego and anti-Szego quadrature rules provide upper and lower bounds for the value of the given integral. The construction of anti-Szego quadrature rules is almost identical to that of Szego quadrature rules in that pairs of associated Szego and anti-Szego rules differ only in the choice of a parameter of unit modulus. Several examples of Szego and anti-Szego quadrature rule pairs are presented.
30.
C. Díaz Mendoza 《Journal of Mathematical Analysis and Applications》2011,379(1):305-315
We study the asymptotic zero distribution of the rescaled Laguerre polynomials, , with the parameter αn varying in such a way that . The connection with the so-called Szeg? curve is shown. 相似文献