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941.
Using the phenomenological relativistic harmonic model (RHM) for quarks, we have obtained the masses of S wave charmonium and bottomonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confinement potential, along with the confined one gluon exchange potential (COGEP). A good agreement with the experimental masses for the ground and the radially excited states is obtained both for the triplet and singlet S wave mesons. The decay properties of the ground state charmonium and bottomonium are investigated. 相似文献
942.
为准确分析含多孔材料有源声学结构的声学性能,利用一种结合(u,p)方程和有限元技术的计算方法对有源声学结构建模,分析声波在多孔材料中传播规律,并进行了实验验证.基于固相位移和流相声压的(u,p)方程对多孔材料固、流两相间强烈耦合进行分析,建立了多孔材料的有限元模型,并对含有多孔材料双层板有源声学结构的声学性能进行了测量... 相似文献
943.
George W. Russell 《珠算》2014,(9):62-64
时值亚太地区商用航空业蓬勃发展之际,美捷香港商用飞机有限公司雄心勃勃,计划全面拓展市场。该公司的财务总监梁若芝(Connie)畅谈这一宏伟蓝图。Connie的母亲对女儿即将到南美任职有些不悦。“‘去哪里?智利在哪里?’母亲问我。 我猜她以为我要去亚马逊。”Connie笑着回忆道。 相似文献
944.
In this paper,we consider the(L,1) state-dependent reflecting random walk(RW) on the half line,which is an RW allowing jumps to the left at a maximal size L.For this model,we provide an explicit criterion for(positive) recurrence and an explicit expression for the stationary distribution.As an application,we prove the geometric tail asymptotic behavior of the stationary distribution under certain conditions.The main tool employed in the paper is the intrinsic branching structure within the(L,1)-random walk. 相似文献
945.
For a given polyhedron K(?)M,the notation RM(K)denotes a regular neigh- borhood of K in M.The authors study the following problem:find all pairs(m,k) such that if K is a compact k-polyhedron and M a PL m-manifold,then R_M(f(K))≌R_M(g(K))for each two homotopic PL embeddings f,g:K→M.It is proved that R_S~(k 2)(S~k)(?)S~k×D~2 for each k(?)2 and some PL sphere S~k(?)S~(k 2)(even for any PL sphere S~k(?)S~(K 2)having an isolated non-locally flat point with the singularity S~(k-1)(?) S~(k 1)such thatπ_1(S~(k 1)-S~(k-1))(?)Z). 相似文献
946.
GLOBAL ASYMPTOTIC STABILITY IN N-SPECIES NONAUTONOMOUS LOTKA-VOLTERRACOMPETITIVE SYSTEMS WITH DELAYS
A delayed n-species nonautonomous Lotka-Volterra type competitive system without dominating instantaneous negative feedback is investigated. By means of a suitable Lyapunov functional, sufficient conditions are derived for the global asymptotic stability of the positive solutions of the system. As a corollary, it is shown that the global asymptotic stability of the positive solution is maintained provided that the delayed negative feedbacks dominate other interspecific interaction effects with delays and the delays are sufficiently small. 相似文献
947.
A.B.El-Rayes AbdEl-MoneimA.Mohamed HamdyM.AbouGabal 《数学物理学报(B辑英文版)》2003,23(3):321-327
A target is assumed to move according to a Brownian motion on the real line. The searcher starts from the origin and moves in the two directions from the starting point.The object is to detect the target. The purpose of this paper is to find the conditions under which the expected value of the first meeting time of the searcher and the target is finite,and to show the existence of a search plan which made this expected value minimum. 相似文献
948.
In this paper, the so-called local likelihood method is suggested for solving the change point problems when the data are distributed as multivariate normal. The detection procedures proposed not only provide strongly consistent estimates for the number and locations of the change points, but also simplify significantly the computation. 相似文献
949.
Gui-Qiang G.CHEN 《数学年刊B辑(英文版)》2015,36(5):715-736
This paper presents several examples of fundamental problems
involving weak continuity and compactness for nonlinear partial
differential equations, in which compensated compactness and related
ideas have played a significant role. The compactness and
convergence of vanishing viscosity solutions for nonlinear
hyperbolic conservation laws are first analyzed, including the
inviscid limit from the Navier-Stokes equations to the Euler
equations for homentropic flow, the vanishing viscosity method to
construct the global spherically symmetric solutions to the
multidimensional compressible Euler equations, and the
sonic-subsonic limit of solutions of the full Euler equations for
multi-dimensional steady compressible fluids. Then the weak
continuity and rigidity of the Gauss-Codazzi-Ricci system and
corresponding isometric embeddings in differential geometry are
revealed. Further references are also provided for some recent
developments on the weak continuity and compactness for nonlinear
partial differential equations. 相似文献
950.
A. KHAKSARI M. ERSHAD H. SHARIF 《数学学报(英文版)》2006,22(4):1189-1196
Strongly irreducible submodules of modules are defined as follows: A submodule N of an Rmodule M is said to be strongly irreducible if for submodules L and K of M, the inclusion L ∩ K ∈ N implies that either L ∈ N or K ∈ N. The relationship among the families of irreducible, strongly irreducible, prime and primary submodules of an R-module M is considered, and a characterization of Noetherian modules which contain a non-prime strongly irreducible submodule is given. 相似文献