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31.
32.
We prove in this paper the blow-up theorem of the generalized solution.and its L^2 mass concentration theorem on the set of blow-up points near the blow-up time of the Cauchy problem for nonlinear Schroedinger equations and give the structure of the set of the blow-up points and the estimates on the blow-up time.Furthermore we extend and improve some results in [2] and [5]. 相似文献
33.
不用Kirchhoff—Love假定的三维弹性板近似理论及其边界条件 总被引:2,自引:2,他引:0
红典弹性板理论采用了著名的克希霍夫(Kirchhoff)-拉甫(Love)的经典基本假定,在卡氏张量坐标xi(i=0,1,2)中,这些基本假定是:(1)略去横向即X0轴向正应变,即假定e00=0;(2)略去横向剪应变,即假定e0a=0,其中a=1,2;(3)略去横向正应力,即假定σ00=0。人们利用这些假定,建立了应变位移关系和应力位移关系,再利用应力平衡的三维方程,通过跨厚度的积分,找到弹性板中 相似文献
34.
The aim of this paper is to present construction of finite element multiscaling function with three coefficients. In order to illuminate the result, two examples are given finally. 相似文献
35.
设二元函数f(x,y)有稳定点P(x_0,y_0),并设f_(xx)(x_0,y_0)=A,f″_(xy)(x_0,y_0)=B,f″_(yy)(x_0,y_0)=C,△=AC-B~。当△=AC-B~2=0时,f(x,y)在点P(x_0,y_0)处是否有极值的问题,一般教科书都未进行过具体地讨论,本文对这一问题进行了初步地探 相似文献
36.
关于局部对称空间中2-调和子流形 总被引:6,自引:0,他引:6
本文研究局部对称完备黎曼流形中的紧致2-调和子流形,得到了这类流形第二基本模式长平方的Pinching定理及推广的J.Simons型积分不等式。 相似文献
37.
A temperature-dependent photoluminescence measurement is performed in CdSe/ZnSe quantum dots with a ZnCdSe quantum well.We deduce the temperature dependence of the exciton linewidth and peak energy of the zero-dimensional exciton in the quantum dots and two-dimensional exciton in the CdSe wetting layer.The experimental data reveal a reduction of homogeneous broadening of the exciton line in the quantum dots in comparison with that in the two-dimensional wetting layer,which indicates the decrease of exciton and optical phonon coupling in the CdSe quantum dots. 相似文献
38.
Exact Solution of an Extended Hubbard Model with Electron—Lattice Interaction for an Organic Ferromagnetic Polymer 下载免费PDF全文
Using an exact diagonalization method,we study an extended Hubbard model with an electron-lattice interaction for an organic ferromagnetic chain with radical coupling.The result shows that the ferromagnetic ground state originates from the antiferromagnetic correlation between adjoining sites,which is enhanced by the on-site e-e repulsion.The intersite e-e repulsion induces the inhomogeneous distribution of the charge density.The dimerization is decreased by the e-e interaction and the radical coupling.The electron-lattice interaction and the radical coupling can transfer the spin density and charge density between the main chain and the radicals. 相似文献
39.
40.
J. J. EGOZCUE J. L. DIAZ-BARRERO V. PAWLOWSKY-GLAHN 《数学学报(英文版)》2006,22(4):1175-1182
The set of probability functions is a convex subset of L1 and it does not have a linear space structure when using ordinary sum and multiplication by real constants. Moreover, difficulties arise when dealing with distances between densities. The crucial point is that usual distances are not invariant under relevant transformations of densities. To overcome these limitations, Aitchison's ideas on compositional data analysis are used, generalizing perturbation and power transformation, as well as the Aitchison inner product, to operations on probability density functions with support on a finite interval. With these operations at hand, it is shown that the set of bounded probability density functions on finite intervals is a pre-Hilbert space. A Hilbert space of densities, whose logarithm is square-integrable, is obtained as the natural completion of the pre-Hilbert space. 相似文献