Wave Mechanics or Wave Statistical Mechanics

By comparison between equations of motion of geometrical optics and that of classical statistical mechanics, this paper finds that there should be an analogy between geometrical optics and classical statistical mechanics instead of geometrical mechanics and classical mechanics. Furthermore, by comparison between the classical limit of quantum mechanics and classical statistical mechanics, it finds that classical limit of quantum mechanics is classical statistical mechanics not classical mechanics, hence it demonstrates that quantum mechanics is a natural generalization of classical statistical mechanics instead of classical mechanics. Thence quantum mechanics in its true appearance is a wave statistical mechanics instead of a wave mechanics.     

Wave Mechanics or Wave Statistical Mechanics

By comparison between equations of motion of geometrical optics and that of classical statistical mechanics, this paper finds that there should be an analogy between geometrical optics and classical statistical mechanics instead of geometrical mechanics and classical mechanics. Furthermore, by comparison between the classical limit of quantum mechanics and classical statistical mechanics, it finds that classical limit of quantum mechanics is classical statistical mechanics not classical mechanics, hence it demonstrates that quantum mechanics is a natural generalization of classical statistical mechanics instead of classical mechanics. Thence quantum mechanics in its true appearance is a wave statistical mechanics instead of a wave mechanics.     

Constrained Wave Equations and Wave Maps

In this paper we establish that wave maps can be obtained by a penalization method if the initial data is well prepared. When the data is not well prepared, we prove that the solution of the penalized equation converges weakly to the solution of the system of coupled equations obtained in [11] by a multi-scale formal analysis. In particular, the interaction between the rapid normal oscillations and the tangential motions creates a new term in the limit system whose well-posedness is proved by using the Nash-Moser Implicit Function Theorem. The first author is funded in part by NSF DMS 0203485.The second author is funded in part by NSF DMS 0101969.     

关于热声压缩机原理的讨论

回顾了驻波、行波热声机械的发展历史 ,分析了行波与驻波热声压缩机的优缺点。介绍行波驻波混合型热声压缩机的工作原理及结构 ,指出了今后研究的重点和方向。     

Study of Novel Slow Wave Circuit for Miniaturized Millimeter Wave Helical Traveling Wave Tube

Two kinds of novel helical slow wave circuit, supported by Chemical Vapor Deposition (CVD) diamond, are presented. They are applying in miniaturized millimeter wave helical traveling wave tube. Cold test characteristic of these circuits are simulated by MAFIA code. Higher performances are achieved with smaller size, compared with conventional circuit supported by BeO rods. The nonlinear analysis is implemented by Beam and Wave Interaction (BWI) module, which is a part of TWTCAD Integrated Framework. Results have been found to be consistent with the expectation. It should be wider apply in microwave and millimeter wave vacuum electronic devices.     

Wave Relations

The wave equation (free boson) problem is studied from the viewpoint of the relations on the symplectic manifolds associated to the boundary induced by solutions. Unexpectedly, there is still something to say about this simple, well-studied problem. In particular, boundaries which do not allow for a meaningful Hamiltonian evolution are not problematic from the viewpoint of relations. In the two-dimensional Minkowski case, these relations are shown to be Lagrangian. This result is then extended to a wide class of metrics and is conjectured to be true also in higher dimensions for nice enough metrics. A counterexample where the relation is not Lagrangian is provided by the Misner space.     

光纤中声波导布里渊散射声波对斯托克斯波的影响

利用全矢量有限元法模拟了单模光纤中声波导布里渊散射R0,m和TR2,m声波模式对斯托克斯波增益、相位调制和双折射的影响.研究结果表明:当布里渊频移与R0,8和TR2,10声波频率相同时,斯托克斯波的增益最大,且增益随泵浦功率的增大而增大;R0,1、TR2,1、TR2,5、TR2,7和TR2,10声波模式对斯托克斯波相位调制较大,且相位调制随泵浦功率的增大呈线性增大,其中TR2,m模对斯托克斯波相位调制比R0,m模大;TR2,1、TR2,5、TR2,7、TR2,10声波模式对斯托克斯波产生较为明显的附加双折射,且附加双折射程度随着泵浦功率的增加呈线性增大.     

Solitary Wave and Wave Front as Viewed From Curvature

The solitary wave and wave front are two important behaviors of nonlinear evolution equations. Geometrically, solitary wave and wave front are all plane curve. In this paper, they can be represented in terms of curvature c(s), which varies with arc length s. For solitary wave when s → ±∞, then its curvature c(s) approaches zero, and when s=0, the curvature c(s) reaches its maximum. For wave front, when s → ±∞, then its curvature c(s) approaches zero, and when s=0, the curvature c(s) is still zero, but c'(s) ≠ 0. That is, s=0 is a turning point. When c(s) is given, the variance at some point (x,y) in stream line with arc length s satisfies a 2-order linear variable-coefficient ordinary differential equation. From this equation, it can be determined qualitatively whether the given curvature is a solitary wave or wave front.     

Periodic Wave,Solitary Wave and Compacton Solutions of a Nonlinear Wave Equation with Degenerate Dispersion

In this letter, we investigate traveling wave solutions of a nonlinear wave equation with degenerate dispersion. The phase portraits of corresponding traveling wave system are given under different parametric conditions. Some periodic wave and smooth solitary wave solutions of the equation are obtained. Moreover, we find some new hyperbolic function compactons instead of well-known trigonometric function compactons by analyzing nilpotent points.     

表面波布拉格声光互作用耦合波方程的研究

定义了压电晶体的增劲声光系数，它反映压电晶体中声光、电光和压电效应共同作用的结果。从参量互作用基本理论出发，同时考虑声光效应、电光效应和压电效应三个因素，用一个压电增劲声光系数来表示三种因素的共同作用，导出表面波声光布拉格互作用的耦合波方程。并求解得出相应衍射效率的计算公式。该式说明在弱声光互作用条件下，衍射导光波强度与超声功率成正比。表面波声光器件具有体积小、工作稳定、能耗小、易于集成等优点。可以用作光偏转器、光调制器、滤光器。在光通信以及各类实时信号处理，如相关、卷积、频谱分析、矩阵光计算等领域具有广泛的应用前景。     

A Wave Automaton for Wave Propagation in Inhomogeneous Anisotropic Media

This paper presents an extension built on a hexagonal grid of the wave automaton, which was introduced in past few years for describing wave propagation in inhomogeneous media. This new method is capable of computing wave propagation in 2D anisotropic media without the need for introducing interpolating schemes. After a comparison of isotropic single scattering with analytical results using Mie theory, the method is used to compute the field scattered by one anisotropic particle for various orientations of its principal axes. Scattering by a collection of anisotropic particles is also presented.     

Slippery Wave Functions

Superfluids and superconductors show a very surprising behavior at low temperatures. As their temperature is reduced, materials of both kinds can abruptly fall into a state in which they will support a persistent, essentially immortal, flow of particles. Unlike anything in classical physics, these flows produce neither friction nor resistance. A major accomplishment of Twentieth Century physics was the development of an understanding of this very surprising behavior via the construction of partially microscopic and partially macroscopic quantum theories of superfluid helium and superconducting metals. Such theories come in two parts: a theory of the motion of particle-like excitations, called quasiparticles, and of the persistent flows itself via a huge coherent excitation, called a condensate. Two people, above all others, were responsible for the construction of the quasiparticle side of the theories of these very special low-temperature behaviors: Lev Landau and John Bardeen. Curiously enough they both partially ignored and partially downplayed the importance of the condensate. In both cases, this neglect of the actual superfluid or superconducting flow interfered with their ability to understand the implications of the theory they had created. They then had difficulty assessing the important advances that occurred immediately after their own great work. Some speculations are offered about the source of this unevenness in the judgments of these two leading scientists.     

Gravitational Wave Holography

We represent and discuss a theory of gravitational holography in which all the involved waves; subject, reference and illuminator are gravitational waves (GW). Although these waves are so weak that no terrestrial experimental set-ups, even the large LIGO, VIRGO, GEO and TAMA facilities, were able up to now to directly detect them they are, nevertheless, known under certain conditions (such as very small wavelengths) to be almost indistinguishable (see P. 962, in Misner, C. W., Thorne, K. S., and Wheeler, J. A. (1973). Gravitation, Freeman, San Francisco.) from their analogue electromagnetic waves (EMW). We, therefore theoretically, show, using the known methods of optical holography and taking into account the very peculiar nature of GW, that it is also possible to reconstruct subject gravitational waves. PACS numbers: 42.40.-i, 42.40.Eq, 04.30.-w, 04.30.Nk     

讲机械波慎以水波为例

水波是一种常见的波，讲机械波时以水波为例，说明波的折射、波的衍射和波的干涉现象，取材方便、实验易做，并且演示现象明显，能够取得很好的教学效果．教科书《物理》第二册“机械波”一章也多次提到了水波这个例子．     

毫米波步进频连续波SAR成像系统研究

研究了一种基于毫米波的步进频连续波合成孔径雷达成像系统.基于算法研究,搭建了成像硬件及软件系统,实现信号扫描及回波信号的采集与处理.处理后的信号通过成像算法计算,获得目标物体的三维图像数据.实验测试了系统x、y、z方向的分辨率,测试结果表明系统x方向分辨率在8～9 mm,y方向分辨率为12 mm,z方向分辨率为40 m...     

Wave Breaking in a Class of Nonlocal Dispersive Wave Equations

Abstract

The Korteweg de Vries (KdV) equation is well known as an approximation model for small amplitude and long waves in di!erent physical contexts, but wave breaking phenomena related to short wavelengths are not captured in. In this work we consider a class of nonlocal dispersive wave equations which also incorporate physics of short wavelength scales. The model is identified by a renormalization of an infinite dispersive di!erential operator, followed by further specifications in terms of conservation laws associated with the underlying equation. Several well-known models are thus rediscovered. Wave breaking criteria are obtained for several models including the Burgers-Poisson system, the Camassa-Holm type equation and an Euler-Poisson system. The wave breaking criteria for these models are shown to depend only on the negativity of the initial velocity slope relative to other global quantities.     

Solitary Wave and Non-traveling Wave Solutions to Two Nonlinear Evolution Equations

By applying the extended homogeneous balance method, we find some new explicit solutions to two nonlinear evolution equations, which include n-resonance plane solitary wave and non-traveling wave solutions.     

正弦波与方波磁光调制的比较分析

基于正弦波磁光调制原理，同时利用利萨如图形方法，对正弦波磁光调制和方波磁光调制进行了计算机模拟．模拟结果表明，正弦波磁光调制具有磁光调制原理所描述的基本特性，并且其偏振角度检测准确度可达到0．001°；而方波磁光调制具有更好的应用特性，不存在波形失真问题，其氏取值不受小角度条件的限制，其偏振角度检测准确度可高于0．001°．对两种磁光调制进行的对比性实验研究，进一步支持了以上结论，表明方波磁光调制无论用于信号调制或用于偏振角度检测都具有独特的优势．另外，在实验中发现了两种磁光调制的限幅效应，并对其形成的原因进行了初步分析．