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81.
A Hamiltonian to describe a spin quantum Hall effect with two types of spin‐orbit coupling is introduced and the eigenfunctions and eigenvalues are obtained for it. It is shown that this Hamiltonian also results by gauging a kinetic energy Hamiltonian by an SU (2) gauge field. The Berry phase is obtained from the model wavefunction for the model and used to define a filling factor. This allows for the calculation of the spin Hall conductivity. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   
82.
 利用任意反射面激光干涉测速(VISAR)系统以及全光纤位移干涉仪(FDI),测量了线膛炮弹丸速度,获得了线膛炮弹丸在0~491 μs内从零加速到140 m/s的速度历史,弹丸运动了20.7 mm,出炮口时的弹丸速度为817 m/s。实验结果表明,影响激光干涉测速技术在内弹道测量中应用的主要因素是炮口烟。研究结果对于深入探索激光干涉测速技术在内弹道测量中的应用有重要的参考意义。  相似文献   
83.
CBERS-02B星HR相机内方位元的在轨标定方法   总被引:1,自引:0,他引:1  
遥感相机内方位元素的在轨标定对遥感图像的定位和测量具有重要意义.利用线阵推扫传感器构像模型,提出了一种对CBERS-02B星HR相机内方位元素进行在轨标定的方法.该方法以内方位元素和姿态角为未知参数,建立地面控制点和相应像点的共线方程组,通过解算共线方程组获得内方位元素.实验证明,用该方法对内方位元素进行在轨标定,具有...  相似文献   
84.
In this article, both the eigenvectors and the eigenvalues of the q‐Bernstein operators have been studied. Explicit formulae are presented for the eigenvectors, whose limit behavior is determined both in the case 0 < q < 1 and in the case q > 1. Because the classical case, where q = 1, was investigated exhaustively by S. Cooper and S. Waldron back in 2000, the present article also discusses the related similarities and distinctions with the results in the classical case. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
85.
In this paper, we consider the problem where λ is a spectral parameter; q(x) ∈ L1(0,1) is complex‐valued function; αs, s = 1,2,3, are arbitrary complex constants that satisfy α2 = α1 + α3 and σ = 0,1. The boundary conditions of this problem are regular, but not strongly regular. Asymptotic formulae for eigenvalues and eigenfunctions of the considered boundary value problem are established. It is proved that all the eigenvalues, except for finite number, are simple and the system of root functions of this spectral problem forms a basis in the space Lp(0,1), 1 < p < ∞ , when ; moreover, this basis is unconditional for p = 2. We note that the considered problem was previously investigated in the condition of α2α1 + α3. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
86.
Let be a bounded open domain of . Let denote the outward unit normal of . We assume that the Steklov problem Δu = 0 in and on has a simple eigenvalue of . Then we consider an annular domain obtained by removing from a small‐cavity size of ε > 0, and we show that under proper assumptions there exists a real valued and real analytic function defined in an open neighborhood of (0,0) in and such that is a simple eigenvalue for the Steklov problem Δu = 0 in and on for all ε > 0 small enough, and such that . Here denotes the outward unit normal of , and δ2,2 ≡ 1 and δ2,n ≡ 0 if n ≥ 3. Then related statements have been proved for corresponding eigenfunctions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
87.
In this work, we study the asymptotic properties of a new Sturm–Liouville problem with retarded argument. Contrary to previous works, differential equation includes eigenparameter as a quadratic function. In the considered problem arise new difficulties. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
88.
关于PageRank的广义二级分裂迭代方法   总被引:1,自引:0,他引:1  
潘春平 《计算数学》2014,36(4):427-436
本文研究计算PageRank的迭代法,在Gleich等人提出的内/外迭代方法的基础上,提出了具有三个参数的广义二级分裂迭代法,该方法包含了内/外迭代法和幂迭代法,并研究了该方法的收敛性.基于该方法的收缩因子的计算公式,讨论了迭代参数可能的选择,通过参数的选择能有效提高内/外迭代法的收敛效率.  相似文献   
89.
Let be graphs. The multicolor Ramsey number is the minimum integer r such that in every edge‐coloring of by k colors, there is a monochromatic copy of in color i for some . In this paper, we investigate the multicolor Ramsey number , determining the asymptotic behavior up to a polylogarithmic factor for almost all ranges of t and m. Several different constructions are used for the lower bounds, including the random graph and explicit graphs built from finite fields. A technique of Alon and Rödl using the probabilistic method and spectral arguments is employed to supply tight lower bounds. A sample result is for any t and m, where c1 and c2 are absolute constants.  相似文献   
90.
This paper proposes a novel extended traffic network model to solve the logit-based stochastic user equilibrium (SUE) problem with elastic demand. In this model, an extended traffic network is established by properly adding dummy nodes and links to the original traffic network. Based on the extended traffic network, the logit-based SUE problem with elastic demand is transformed to the SUE problem with fixed demand. Such problem is then further converted to a linearly constrained convex programming and addressed by a predictor–corrector interior point algorithm with polynomial complexity. A numerical example is provided to compare the proposed model with the method of successive averages (MSA). The numerical results indicate that the proposed model is more efficient and has a better convergence than the MSA.  相似文献   
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