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971.
论述用L定义光学的哈密顿H,并给出哈密顿公式的基本方程式,利用哈密顿方程式,在旋转对称的光学系统里追迹光线,并利用哈密顿公式得到折射面和透镜的简单结果。最后通过举例说明这个方法是可行的。 相似文献
972.
本文证明了下列源于Veldman等人的一个猜想;设G是阶为n≥13的1—tough图且对所有独立集x,y,z有d(x) d(y) d(z)≥(3n-14)/2,则G是哈米顿的。 相似文献
973.
Cayley图的Hamilton性的若干问题 总被引:3,自引:0,他引:3
综述近二十年来,研究Cayley图的Hamilton圈的若干新成果,并提出一些未解决问题。 相似文献
974.
975.
976.
In this paper, we discuss the Poincare bifurcation of a cubic Hamiltonian system with homoclinic loop. We prove that the system can generate at most seven limit cycles after a small perturbation of general cubic polynomials. 相似文献
977.
Nonlinear amplitude equations for the near-threshold behavior of twisted extensible elastic rods under tension with inertial
and dissipative dynamics are derived. In the inertial case localized solutions to the amplitude equations are derived and
a linear stability criterion for the pulse solutions is obtained using the Hamiltonian formulation of the problem. 相似文献
978.
W.-M. Wang 《Journal of Functional Analysis》2008,254(11):2926-2946
We prove that the Sobolev norms for a 1-D periodic Schrödinger equation remain bounded under small resonant perturbations. 相似文献
979.
The critical coupling length Lc is the most important design parameter of an integrated-optic directional coupler, which is the basic building block of a variety of optical integrated circuits. The existing methods of estimating Lc of a Ti in-diffused waveguide directional coupler on LiNbO3 substrate are based on the beam propaga tion method (BPM), which requires huge computing time. A considerably simpler and computationally faster analytical method involving only multiplication of 2 x 2 matrices with no iterations is described in this article. A staircase type step-index profile is generated from the one-dimensional effective index profile in the lateral direction by partitioning the latter into a large number of thin sections of different refractive indices. The overall transfer matrix of the step-index layered structure so obtained may be computed by the progressive multiplication of individual transfer matrices (2 x 2) relating the field components in adjacent layers. Hence the wave amplitude in any layer may be computed as a function of the input wave amplitude for different angles of incidence. This method has been successfully employed to compute the propagation constants for symmetric and asymmetric guided modes in the coupled region of the directional coupler and hence compute the coupling length. The values of Lc computed for a variety of devices agree closely with the published experimental results reported by several research groups. The computer program implementing the model runs reasonably fast in an ordinary PC and is versatile enough to consider arbitrary waveguide dimensions. Ti film thickness, and diffusion parameters for any wavelength of input light and for both transverse electric and transverse magnetic polarizations. 相似文献
980.
David Tankus 《Discrete Mathematics》2007,307(15):1833-1843
There are various greedy schemas to construct a maximal path in a given input graph. Associated with each such schema is the family of graphs where it always results a path of maximum length, or a Hamiltonian path/cycle, if there exists one. Considerable amount of work has been carried out, regarding the characterization and recognition problems of such graphs. We present here a systematic listing of previous results of this type and fill up most of the remaining empty entries. 相似文献