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991.
Wolfgang Knirsch Georg Schneider 《Journal of Mathematical Analysis and Applications》2006,320(1):403-414
In this paper we investigate Hankel operators with anti-holomorphic symbols ∈L2(C,m|z|), where are general Fock spaces. We will show that is not continuous if the corresponding symbol is not a polynomial . For polynomial symbols we will give necessary and sufficient conditions for continuity and compactness in terms of N and m. For monomials we will give a complete characterization of the Schatten-von Neumann p-class membership for p>0. Namely in case 2k<m the Hankel operators are in the Schatten-von Neumann p-class iff p>2m/(m−2k); and in case 2k?m they are not in the Schatten-von Neumann p-class. 相似文献
992.
In this paper, the solution of the nonlinear evolution inclusion problem of the form u′(t)+B(t,u(t))∋f(t) is studied. In this problem, the operators are of type (M) or type (S+), which are different from those of pseudo-monotone operators that had been studied by many authors. At the same time, we study the perturbation problem. In fact, many kinds of evolution equations can be generalized by this problem. The former results are improved and generalized by our conclusions, and we will give more applications. 相似文献
993.
Satoru Fujishige 《Discrete Applied Mathematics》2006,154(6):950-970
In the theory of two-sided matching markets there are two standard models: (i) the marriage model due to Gale and Shapley and (ii) the assignment model due to Shapley and Shubik. Recently, Eriksson and Karlander introduced a hybrid model, which was further generalized by Sotomayor. In this paper, we propose a common generalization of these models by utilizing the framework of discrete convex analysis introduced by Murota, and verify the existence of a pairwise-stable outcome in our general model. 相似文献
994.
995.
We present direct measurements of the lifetime of the 4F5/2 and 2H(2)9/2 manifold in Nd3+:YLiF4, using a fluorescence pump-probe technique. The technique populates the 4F5/2 and 2H(2)9/2 manifold directly with a pump pulse. Via excited state absorption from this excited manifold, the 2F(2)5/2 manifold of Nd3+ is populated with a delayed probe pulse. The population in the 4F5/2 and 2H(2)9/2 manifold is monitored as a function of time by observing the change in integrated UV fluorescence from the 2F(2)5/2 manifold for each time delay between pump and probe pulses. The pump and probe beams come from the fundamental and second harmonic wavelengths of a femtosecond Ti:sapphire regenerative amplifier. The measured lifetime agrees well with the energy gap law, based on other nonradiative lifetime measurements from the literature for Nd3+:YLiF4. 相似文献
996.
Vladimír Špirko 《Journal of Molecular Spectroscopy》2006,235(2):268-270
The potential energy curve of Be2 in its ground electronic state is constructed by morphing accurate MR-CI ab initio potentials from the literature to available experimental ro-vibrational data within the framework of the reduced potential curve (RPC) approach of Jen? and Plíva [Adv. At. Mol. Phys. 19 (1983) 265-307]. The resulting potential energy curves are in close harmony with experiment allowing thus for reliable prediction of the so-far experimentally unprobed part of the molecular potential energy function. 相似文献
997.
Shonda Gosselin 《Discrete Mathematics》2010,310(4):671-680
For an integer n and a prime p, let . In this paper, we present a construction for vertex-transitive self-complementary k-uniform hypergraphs of order n for each integer n such that for every prime p, where ?=max{k(2),(k−1)(2)}, and consequently we prove that the necessary conditions on the order of vertex-transitive self-complementary uniform hypergraphs of rank k=2? or k=2?+1 due to Potoňick and Šajna are sufficient. In addition, we use Burnside’s characterization of transitive groups of prime degree to characterize the structure of vertex-transitive self-complementary k-hypergraphs which have prime order p in the case where k=2? or k=2?+1 and , and we present an algorithm to generate all of these structures. We obtain a bound on the number of distinct vertex-transitive self-complementary graphs of prime order , up to isomorphism. 相似文献
998.
Hirobumi Mizuno 《Discrete Mathematics》2010,310(4):782-791
We give a decomposition formula for the determinant on the bond scattering matrix of a regular covering of G. Furthermore, we define an L-function of G, and give a determinant expression of it. As a corollary, we express the determinant on the bond scattering matrix of a regular covering of G by means of its L-functions. 相似文献
999.
This paper is concerned with the existence for impulsive semilinear differential equations with nonlocal conditions. Using the techniques of approximate solutions and fixed point, existence results are obtained, for mild solutions, when the impulsive functions are only continuous and the nonlocal item is Lipschitz in the space of piecewise continuous functions, is not Lipschitz and not compact, is continuous in the space of Bochner integrable functions, respectively. 相似文献
1000.
Francisco J. Fernández-Polo 《Journal of Functional Analysis》2010,259(2):343-358
We establish several generalisations of Urysohn's lemma in the setting of JB∗-triples which provide full answers to Problems 1.12 and 1.13 in Fernández-Polo and Peralta (2007) [22]. These results extend the previous generalisations obtained by C.A. Akemann, G.K. Pedersen and L.G. Brown in the setting of C∗-algebras. A generalised Kadison's transitivity theorem is established for finite sums of pairwise orthogonal compact tripotents in JBW∗-triples. We introduce the notion of positively open tripotent in the bidual of a JB∗-triple as an extension of a concept which was already considered in the setting of ternary rings of operators. We investigate the connections appearing between positively open tripotents and hereditary inner ideals. 相似文献