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排序方式: 共有258条查询结果,搜索用时 11 毫秒
71.
In this paper, we deal with the complex Baskakov-Sz ′asz-Durrmeyer mixed operators and study Voronovskaja type results with quantitative estimates for these operators attached to analytic functions of ...  相似文献   
72.
求出了一般波包的中心和宽度在一维均匀场中的变化规律,波包的中心遵循经典粒子的运动规律,宽度的平方则以时间的二次函数增长,但动量空间的相应波包却保持其宽度不变,特别是平面波在运动过程中仍保持为平面波,对Gauss波包,求出了波函数随时间变化的显式,验证了一般结论。  相似文献   
73.
In this paper, the Bayes estimator of the error variance is derived in a linear regression model, and the parametric empirical Bayes estimator (PEBE) is constructed. The superiority of the PEBE over the least squares estimator (LSE) is investigated under the mean square error (MSE) criterion. Finally, some simulation results for the PEBE are obtained.  相似文献   
74.
In this paper we prove a perturbation result for a new type of eigenvalue problem introduced by D. Motreanu and P.D. Panagiotopoulos (1998). The perturbation is made in the nonsmooth and nonconvex term of a double eigenvalue problem on a spherlike type manifold considered in Multiple solutions for a double eigenvalue hemivariational inequality on a spherelike type manifold (to appear in Nonlinear Analysis). For our aim we use some techniques related to the Lusternik-Schnirelman theory (including Krasnoselski's genus) and results proved by J.N. Corvellec et al. (1993), M. Degiovanni and S. Lancelotti (1995), and V.D. Rdulescu and P.D. Panagiotopoulos (1998). We apply these results in the study of some problems arising in Nonsmooth Mechanics.  相似文献   
75.
Based on a study of a minimization problem, we present the following results applicable to possibly nonconvex sets in a Banach space: an approximate projection result, an extended extremal principle, a nonconvex separation theorem, a generalized Bishop-Phelps theorem and a separable point result. The classical result of Dieudonné (on separation of two convex sets in a finite-dimensional space) is also extended to a nonconvex setting.  相似文献   
76.
The reaction mechanism of AsCl3 with H2 has been studied by using the method of BHandHLYP in Density Functional Theory (DFT) at the 6-311G** basis set. The transition state of each reaction is verified via the analysis of vibration mode and Intrinsic Reaction Coordinate (IRC). Meanwhile,single-point energy has been calculated at the QCISD(T)/6-311G** level,and the zero-point energy correction has been made to the total energy and reaction energy barrier. It shows that AsCl3 reacts with H2 to first result in AsHCl2 which may incline to self-decompose and finally afford the product As2,or continue to react with H2 to provide the product AsH3. The computing result demonstrates that the former is the main reaction channel.  相似文献   
77.
It is proved that for any given sequence (σ n ,n ∈ ℕ)=Γ0 ⊂ Γ, where Γ is the set of all directions in ℝ2 (i.e., pairs of orthogonal straight lines) there exists a locally integrable functionf on ℝ2 such that: (1) for almost all directionsσ ∈ Γ\Γ0 the integral ∫f is differentiable with respect to the familyB 2σ of open rectangles with sides parallel to the straight lines fromσ: (2) for every directionσ n ∈ Γ0 the upper derivative of ∫f with respect toB 2σ n equals +∞; (3) for every directionσ ∈ Γ the upper derivative of ∫ |f| with respect toB 2σ equals +∞.  相似文献   
78.
二阶非线性边值问题解的存在唯一性定理   总被引:4,自引:0,他引:4  
考虑方程y‘’+f(t,y,y‘)=0在边值条件y(a)=A,y(b)=B下解的存在唯一性,要求f满足L^2-Caratheodory条件,在L^2空间中利用映象原理得到解唯一存在的最优结果。  相似文献   
79.
In this paper, we discuss a possibility of studying properties of dark energy in long baseline neutrino oscillation experiments. We consider two types of models of neutrino dark energy. For one type of models the scalar field is taken to be quintessence-like and for the other phantom-like. In these models the scalar fields couple to the neutrinos to give rise to spatially varying neutrino masses. We will show that the two types of models predict different behaviors of the spatial variation of the neutrino masses inside the Earth and consequently result in different signals in long baseline neutrino oscillation experiments.  相似文献   
80.
 针对反射体布拉格光栅谱组束中缺乏精密控制仪器的实验条件,采用透镜作为光束入射角和准直控制器件,设计了一种结构简单的谱组束系统。基于衍射效率方程,得到了光栅最佳设计参数;基于像差理论,得到了透镜最佳设计参数。针对该设计系统,对影响组束效果的因素进行了分析,并对组束效果进行了预测。结果表明:当激光束的谱宽小于1.5 nm时,设计系统的组束效率能超过90%;而当光束的谱宽达到2.1 nm时,设计系统也能获得超过88.7%的组束效率。  相似文献   
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