应用LSI实现WEB图片的索引和查询

应用奇异值分解方法，分析相关文本词条和图片语义的关系，构造了一个图片“潜在语义索引”模型，用于缓解传统的许多WEB图片检索系统在索引和查询中遇到的同义词和多义词问题，实现语义索引和查询实验表明，该模型能有效地改善图片的索引和查询性能。     

Maximal proper acceleration and the structure of spacetime

A limiting proper acceleration in nature follows deductively from known physics and compels the union of spacetime and four-velocity space into a maximal-acceleration invariant phase space having an intrinsic Kaluza-Klein-type fiber-bundle structure with manifest gauge properties. The Riemann curvature scalar of the bundle manifold is determined, and a possible action principle is considered to serve as a basis for the generation of field equations.1. This is an expanded version of an invited paper presented at the Fifth Marcel Grossmann Meeting at the University of Western Australia, 8–12 August 1988.     

A one-dimensional Schrödinger operator with point interactions on Sobolev spaces

A one-dimensional Schrödinger operator with point interactions on Sobolev spaces is studied on the basis of the extension theory of nondensely defined operators.     

The center conjecture for non-exceptional buildings

We prove the center conjecture for spherical buildings of non-exceptional type. Our proof uses the point-line spaces associated with these buildings.     

Integrable structure of the field theory of open superstrings

We find asymptotic expansions in the “string mass” μ for μ-deformed Γ-functions and Neumann coefficients characterizing the three-string vertex in the light-cone gauge of the field theory of open superstrings on a maximally supersymmetric pp-wave background. Dedicated to the 80th birthday of Academician Anatolii Alekseevich Logunov __________ Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 149, No. 3, pp. 381–385, December, 2006.     

一般化凸空间上KKM定理的另一种形式及其应用

§1Introductionandpreliminaries In1929,Knaster,Kuratowski,andMazurkiewicz(simply,KKM)[1]deducedthe celebratedKKMtheorem.TheKKMtheory,firstcalledbySehiePark,isthestudyof applicationsofvariousequivalentformulationsoftheclassicalKKMprinciple[2].Atthe beginning,thetheorywasmainlystudiedonconvexsubsetsofHausdorfftopologicalvector spaces[3],butlater,ithasbeenextendedtoconvexspacesbyLassonde[4],andtospaces havingcertainfamiliesofcontractiblesubsets(simply,C-spacesorH-spaces)by Horvath[5].Mor…     

Galilean-Covariant Clifford Algebras in the Phase-Space Representation

We apply the Galilean covariant formulation of quantum dynamics to derive the phase-space representation of the Pauli–Schrödinger equation for the density matrix of spin-1/2 particles in the presence of an electromagnetic field. The Liouville operator for the particle with spin follows from using the Wigner–Moyal transformation and a suitable Clifford algebra constructed on the phase space of a (4 + 1)-dimensional space–time with Galilean geometry. Connections with the algebraic formalism of thermofield dynamics are also investigated.     

On the singularities of the gradient of the solution to the Dirichlet-Neumann problem outside a plane cut

The problem considered in this paper deals with the Laplace equation outside a cut of sufficiently arbitrary form. The Dirichlet condition is given on one side of the cut and the Neumann condition on the other. Using the integral representation for the solution, we obtain explicit asymptotic formulas describing the singularity of the gradient of the solution at the edges of the cut. We discuss the effect of the disappearance of the singularity.Translated from Matematicheskie Zametki, vol. 77, no. 3, 2005, pp. 364–377Original Russian Text Copyright © 2005 by P. A. Krutitskii, A. I. Sgibnev.This revised version was published online in April 2005 with a corrected issue number.     

Fréchet spaces with unconditional base

A nonnormable ?-space possessing an unconditional basis is not necessarily isomorphic to a generalized Köthe space.