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991.
992.
Alexander Kheifets 《Integral Equations and Operator Theory》1995,21(3):334-341
This paper gives a negative answer to a question due to V.M. Adamjan, D.Z. Arov and M.G. Krein, and (what is the same) gives a counterexample to D.Sarason's conjecture* concerning exposed points inH
1. 相似文献
993.
We show that the cartesian closed category of compactly generated Hausdorff spaces is regular, but is neither exact, nor locally cartesian closed. In fact we find a coequalizer of an equivalence relation which is not stable under pullback. 相似文献
994.
995.
In this paper we introduce a notion ofrandom interval graphs: the intersection graphs of real, compact intervals whose end points are chosen at random. We establish results about the number of edges, degrees, Hamiltonicity, chromatic number and independence number of almost all interval graphs. 相似文献
996.
997.
Let f be the function which maps conformally a given doubly-connected domain Ω onto a circular annulus, and let . In this paper we consider the problem of determining the main singularities of the function H in compl(). Our purpose is to provide information regarding the location and nature of such singularities, and to explain how this information can be used to improve the efficiency of certain expansion methods for numerical conformal mapping. 相似文献
998.
The Herrlich's problem from [8] whether there are nontrivial classes of topological spaces that are both almost reflective or injective and almost coreflective or projective, is investigated in a more general setting using cone and cocone modifications of the classes used in the problem. We look also at the problem for uniform spaces. Typical results: There is no nontrivial multiprojective and orthogonal class of topological spaces; There is a reflective class of uniform spaces that is almost coreflective in Unif.Work on this paper was initiated while the first author was a C.N.R. visitor of the University of L'Aquila. Partial financial assistence by Charles University Grant 349/1994 is also acknowledged. 相似文献
999.
Summary The Tricomi problem with Neumann boundary condition is reduced to a degenerate problem in the elliptic region with a non-local boundary condition and to a Cauchy problem in the hyperbolic region. A variational formulation is given to the elliptic problem and a finite element approximation is studied. Also some regularity results in weighted Sobolev spaces are discussed. 相似文献
1000.
In this paper we discuss fully symmetric integration rules of degree 7 and 9 for the 4-cube. In particular we are interested in good rules. (i.e. rules with all the evaluation points inside the cube and all the weights positive).This work was supported by the Norwegian Research Council for Sciences and Humanities. 相似文献