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911.
912.
913.
Theoretical calculations employing the modified over-barrier model to investigate single and double ionization cross sections of helium in collisions with highly charged ions are presented in the strong perturbation region. It shows the velocity and charge state dependences of cross sections, which coincides with the available experimental data. In order to determine the reliability of this model for partially stripped projectiles, the cross-section ratios have been measured for CZp+, OZp+-He (Zp=1-4) by the coincidence technique in the velocity range of 1-4.5 a.u. The calculated results are approximately in agreement with the experimental data. 相似文献
914.
B. Ding M. E. Pemble A. V. Korovin U. Peschel S. G. Romanov 《Applied Physics A: Materials Science & Processing》2011,103(3):889-894
Hybrid metal-dielectric photonic crystals assembled from an opal film coated by a gold film are designed in order to realize
optical spectra that emanate from mixing Bloch modes in the opal and surface plasmon polaritons in corrugated gold films.
The photonic crystal provides a spatial template for the gold film profile and modifies the electromagnetic vacuum in the
vicinity to the gold layer. Reflectance spectroscopy was applied to deconvolute the plasmonic and photonic bandgap components
in the optical response of hybrid crystals as opposite to their mixed appearance in the transmission spectra. 相似文献
915.
The paper discusses recursive computation problems of the criterion functions of several least squares type parameter estimation methods for linear regression models, including the well-known recursive least squares (RLS) algorithm, the weighted RLS algorithm, the forgetting factor RLS algorithm and the finite-data-window RLS algorithm without or with a forgetting factor. The recursive computation formulas of the criterion functions are derived by using the recursive parameter estimation equations. The proposed recursive computation formulas can be extended to the estimation algorithms of the pseudo-linear regression models for equation error systems and output error systems. Finally, the simulation example is provided. 相似文献
916.
运用正规族理论研究了整函数与其高阶导数分担无穷级函数增长级与超级的相关结果.从亚纯函数超级大于零而使球面导数无界的角度出发,然后综合运用Pang-Zaclman引理,数学归纳法和Nevanlinna理论等方法证明了该结果,推广和改进了已有的结果. 相似文献
917.
Wei Ding 《数学学报(英文版)》2014,30(6):933-948
In this paper, we introduce new Triebel–Lizorkin and Besov Spaces associated with the different homogeneities of two singular integral operators. We then establish the boundedness of composition of two Calder′on–Zygmund singular integral operators with different homogeneities on these Triebel–Lizorkin and Besov spaces. 相似文献
918.
We study the semi-classical ground states of the nonlinear Maxwell–Dirac system: $$\begin{aligned} \left\{ \begin{array}{l} \alpha \cdot \left( i\hbar \nabla + q(x)\mathbf{A }(x)\right) w-a\beta w -\omega w - q(x)\phi (x) w = P(x)g(\left| w\right| ) w\\ -\Delta \phi =q(x)\left| w\right| ^2\\ -\Delta {A_k}=q(x)(\alpha _k w)\cdot \bar{w}\ \ \ \ k=1,2,3 \end{array} \right. \end{aligned}$$ for \(x\in \mathbb{R }^3\) , where \(\mathbf{A }\) is the magnetic field, \(\phi \) is the electron field and \(q\) describes the changing pointwise charge distribution. We develop a variational method to establish the existence of least energy solutions for \(\hbar \) small. We also describe the concentration behavior of the solutions as \(\hbar \rightarrow 0\) . 相似文献
919.
Bernstein Polynomial Estimation in the Partially Linear Model under Monotonicity Constraints
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In this paper, a Bernstein-polynomial-based likelihood
method is proposed for the partially linear model under monotonicity constraints.
Monotone Bernstein polynomials are employed to approximate the monotone
nonparametric function in the model. The estimator of the regression parameter
is shown to be asymptotically normal and efficient, and the rate of convergence
of the estimator of the nonparametric component is established, which could be
the optimal under the smooth assumptions. A simulation study and a real data
analysis are conducted to evaluate the finite sample performance of the proposed
method. 相似文献
920.
浙江杜鹃花属植物的研究 总被引:3,自引:0,他引:3
本文报道了浙江产杜鹃花属植物16 种及 1 变型其中白花满山红为新变型,丁香杜 鹃和江西杜码为浙江分布新记录.根据最新分类系统,本属分为 5 个亚属,在浙江都有 它们的代表,说明浙江的杜鹃花属植物在该属系统研究中的地位,此外,文中还附有分种 检 索表和种类列举 ( 分布、用途 ) 相似文献