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排序方式: 共有491条查询结果,搜索用时 31 毫秒
31.
Shuxia Pan 《Journal of Mathematical Analysis and Applications》2008,346(2):415-424
This paper is concerned with the existence of traveling wave fronts for delayed non-local diffusion systems without quasimonotonicity, which can not be answered by the known results. By using exponential order, upper-lower solutions and Schauder's fixed point theorem, we reduce the existence of monotone traveling wave fronts to the existence of upper-lower solutions without the requirement of monotonicity. To illustrate our results, we establish the existence of traveling wave fronts for two examples which are the delayed non-local diffusion version of the Nicholson's blowflies equation and the Belousov-Zhabotinskii model. These results imply that the traveling wave fronts of the delayed non-local diffusion systems without quasimonotonicity are persistent if the delay is small. 相似文献
32.
Konstantin Runovski Hans-Jürgen Schmeisser 《Journal of Fourier Analysis and Applications》2008,14(1):16-38
Means and families of operators generated by Bochner-Riesz kernels are studied. Some sharp results on their convergence are
achieved. The equivalence of the approximation errors of these methods to smoothness quantities related to the Laplacian is
proved.
相似文献
33.
We explicitly compute the Green’s function of the spinor Klein–Gordon equation on the Riemannian and Lorentzian manifolds of the form M0×?×MN, with each factor being a space of constant sectional curvature. Our approach is based on an extension of the method of spherical means to the case of spinor fields and on the use of Riesz distributions. 相似文献
34.
George TEPHNADZE 《数学物理学报(B辑英文版)》2014,(5):1593-1602
The main aim of this paper is to find necessary and sufficient conditions for the convergence of Walsh-Kaczmarz-Fej′er means in the terms of the modulus of continuity on the Hardy spaces Hp, when 0〈p≤1/2. 相似文献
35.
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37.
研究了球型平移网络对周期函数的逼近问题.文章首先将基函数eimx分别表示成为两种球型平移网络.进一步,将有关多重Fourier级数的Bochner-Riesz平均表示成为球型平移网络的形式.在此基础上构造出了两类球型平移网络序列,并借助于有关Bochner-Riesz平均对Lp空间中函数的逼近结果给出了这两类球型平移网络序列在Lp空间中的逼近阶. 相似文献
38.
A functional analysis of NOx levels: location and scale estimation and outlier detection 总被引:1,自引:0,他引:1
Manuel Febrero Pedro Galeano Wenceslao González-Manteiga 《Computational Statistics》2007,22(3):411-427
This paper analyzes the NOx levels measured by a control station near a power plant by using techniques for functional data.
First, we test for differences between the levels on working and non working days. Second, we obtain several location estimators
and confidence sets of the center of the functional distribution. Third, we provide scale estimators and confidence sets of
the dispersion of the functional distribution. Finally, a distance based procedure provides a criterion to determinate the
presence of outlying observations, which allows to detect relevant NOx levels. 相似文献
39.
Shuichi Sato 《Journal of Mathematical Analysis and Applications》2003,278(2):308-323
We prove some weighted estimates for certain Littlewood-Paley operators on the weighted Hardy spaces Hwp (0<p?1) and on the weighted Lp spaces. We also prove some weighted estimates for the Bochner-Riesz operators and the spherical means. 相似文献
40.
Opacity of high-Z element plasma in non-local thermodynamic equilibrium (NLTE) is calculated. In the calculation, a collisional radiative model in detailed-configuration-accounting (DCA) is applied to population calculations for NLTE plasmas. Configuration-averaged rate coefficients that needed in the rate equations are obtained based on the first order perturbation theory. The Hatree-Fock-Slater self-consistent-field method is used to calculate the electron wave functions. The spin-orbit splitting is included in the spectrum calculations. The unresolved transition array method is used in the opacity calculations. The calculated frequency-dependent opacity of high-Z plasma Lu is presented. The comparison shows that the present spectrum agrees with another theoretical result well except that the present one shifts a little to the lower energy due to its lower mean ionization stage. The effects of highly doubly excited states on ionization balance and on the opacity are investigated. The mean ionization stage increases more than three stages when doubly excited states 5l6l′ and 5l5l′ are not included in the population calculations and the absorption spectrum also shifts to the higher energy. 相似文献