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121.
By using a Bäcklund transformation and the multi-linear variable separation approach, we find a new general
solution of a (2+1)-dimensional generalization of the nonlinear
Schrödinger system. The new “universal” formula is defined, and then, rich coherent structures can be found by selecting corresponding
functions appropriately. 相似文献
122.
In the real-world application of face recognition system, owing to the difficulties of collecting samples or storage space of systems, only one sample image per person is stored in the system, which is so-called one sample per person problem. Moreover, pose and illumination have impact on recognition performance. We propose a novel pose and illumination robust algorithm for face recognition with a single training image per person to solve the above limitations. Experimental results show that the proposed algorithm is an efficient and practical approach for face recognition. 相似文献
123.
Neji Khelifi 《Journal of Russian Laser Research》2008,29(3):274-287
Adiabatic and diabatic study for all the states dissociating below the ionic limit [i.e., Na (3s, 3p, 4s, 3d, 4p, 5s, 4d,
and 4f) + H (1s)] in 1Σ+ and 3Σ+ symmetries are presented. Adiabatic results are also reported for 1,3Π and 1,3Δ symmetries. Pseudo-potential, operatorial core-valence correlation, and full valence CI approaches combined with an efficient
diabatization procedure are used in these ab initio calculations. Our vibrational-level spacings and spectroscopic constants
are in good agreement with the available experimental data for the low-lying states. Diabatic potentials and dipole moments
are analyzed, revealing the strong imprint of the ionic state in the 1Σ+ adiabatic states. The hydrogen electron affinity correction was taken into account by the use of the efficient diabatization
method. This leads to a better agreement with the available experimental data. Experimental suggestions are also given for
the higher excited states based on their unusual behavior. 相似文献
124.
125.
Yarema A. Prykarpatskyy 《Journal of Nonlinear Mathematical Physics》2016,23(1):92-107
A regular gradient-holonomic approach to studying the Lax type integrability of the Ablowitz–Ladik hierarchy of nonlinear Lax type integrable discrete dynamical systems in the vertex operator representation is presented. The relationship to the Lie-algebraic integrability scheme is analyzed and the connection with the τ-function representation is discussed. 相似文献
126.
Importance sampling Monte Carlo offers powerful approaches to approximating Bayesian updating in sequential problems. Specific classes of such approaches are known as particle filters. These procedures rely on the simulation of samples or ensembles of the unknown quantities and the calculation of associated weights for the ensemble members. As time evolves and/or when applied in high-dimensional settings, such as those of interest in many data assimilation problems, these weights typically display undesirable features. The key difficulty involves a collapse toward approximate distributions concentrating virtually all of their probability on an implausibly few ensemble members.
After reviewing ensembling, Monte Carlo, importance sampling and particle filters, we present some approximations intended to moderate the problem of collapsing weights. The motivations for these suggestions are combinations of (i) the idea that key dynamical behavior in many systems actually takes place on a low dimensional manifold, and (ii) notions of statistical dimension reduction. We illustrate our suggestions in a problem of inference for ocean surface winds and atmospheric pressure. Real observational data are used. 相似文献
127.
R. Bachelard A. Antoniazzi C. Chandre D. Fanelli X. Leoncini M. Vittot 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,42(1):125-132
The intensity of an electromagnetic wave interacting self-consistently
with a beam of charged particles as in a free electron laser, displays large
oscillations due to an aggregate of particles, called the macro-particle. In
this article, we propose a strategy to stabilize the intensity by re-shaping
the macro-particle. This strategy involves the study of the linear stability
(using the residue method) of selected periodic orbits of a mean-field model. As
parameters of an additional perturbation are varied, bifurcations occur in the
system which have drastic effect on the modification of the self-consistent
dynamics, and in particular, of the macro-particle. We show how to obtain an
appropriate tuning of the parameters which is able to strongly decrease the
oscillations of the intensity without reducing its mean-value. 相似文献
128.
SHENShou-Feng PANZu-Liang ZHANGJun 《理论物理通讯》2004,42(4):565-567
The variable separation approach method is very useful to solving (2 1)-dimensional integrable systems.But the (1 1)-dimensional and (3 1)-dimensional nonlinear systems are considered very little. In this letter, we extend this method to (1 1) dimensions by taking the Redekopp system as a simp!e example and (3 1)-dimensional Burgers system. The exact solutions are much general because they include some arbitrary functions and the form of the (3 1)-dimensional universal formula obtained from many (2 1)-dimensional systems is extended. 相似文献
129.
We propose a two-color scheme of atom waveguides and one-dimensional (1D) optical lattices using evanescent wave fields of different transverse modes around an optical micro/nano-fiber. The atom guide potential can be produced when the optical fiber carries a red-detuned light with TE01 mode and a blue-detuned light with HEll mode, and the 1D optical lattice potential can be produced when the red-detuned light is transformed to the superposition of the TE01 mode and HE11 mode. The two trapping potentials can be transformed to each other for accurately controlling mode transformation for the red-detuned light. This might provide a new approach to realize flexible transition between the guiding and trapping states of atoms. 相似文献
130.
采用分子静力学方法结合量子修正的 Sutton-Chen多体势研究了含圆孔的纳米薄膜在单向加载过程中的力学行为,并采用共近邻分析方法研究了薄膜的微结构演化过程.模拟结果表明:孔洞的引入显著地降低了纳米薄膜的杨氏模量和屈服应力;在拉伸过程中,孔洞的形状随着应变的增加逐渐由圆形变为椭圆形,最终孔洞闭合;纳米薄膜在进入塑性变形阶段后,薄膜内部出现原子的堆跺层错,这种层错结构的出现是肖克莱不全位错在薄膜内部沿着{111}面的[112]方向运动的结果.
关键词:
纳米薄膜
力学性质
位错
分子静力学 相似文献