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1.
Zeng -Gui Chen 《International Journal of Infrared and Millimeter Waves》1993,14(2):197-211
A cylindrical waveguide gyro-peniotron amplifier is analysed theoretically in this paper. By a ballistic method and directly using the energy conservation in the beam-wave system, a set of interaction equations for the cylindrical waveguide gyro-peniotron amplifier is derived. Computer simulation shows that under defined conditions an interaction efficiency of 47%, an output power of 240kW at a gain of 22. 5 dB and a 3 dB-instantaneous bandwidth of 1. 9% for a central frequency of 35GHz, TE03 mode gyro-peniotron amplifier could be achieved. The influence of the operation parameters on the amplifier performance is also presented. 相似文献
2.
C. S. Unnikrishnan 《Pramana》2005,65(3):359-379
I discuss in detail the result that the Bell’s inequalities derived in the context of local hidden variable theories for discrete
quantized observables can be satisfied only if a fundamental conservation law is violated on the average. This result shows
that such theories are physically nonviable, and makes the demarcating criteria of the Bell’s inequalities redundant. I show
that a unique correlation function can be derived from the validity of the conservation law alone and this coincides with
the quantum mechanical correlation function. Thus, any theory with a different correlation function, like any local hidden
variable theory, is incompatible with the fundamental conservation laws and space-time symmetries. The results are discussed
in the context of two-particle singlet and triplet states, GHZ states, and two-particle double slit interferometry. Some observations
on quantum entropy, entanglement, and nonlocality are also discussed. 相似文献
3.
We study weno(2r − 1) reconstruction [D.S. Balsara, C.W. Shu, Monotonicity prserving weno schemes with increasingly high-order of accuracy, J. Comput. Phys. 160 (2000) 405–452], with the mapping (wenom) procedure of the nonlinear weights [A.K. Henrick, T.D. Aslam, J.M. Powers, Mapped weighted-essentially-non-oscillatory schemes: achieving optimal order near critical points, J. Comput. Phys. 207 (2005) 542–567], which we extend up to weno17 (r=9). We find by numerical experiment that these procedures are essentially nonoscillatory without any stringent cfl limitation (cfl∈[0.8,1]), for scalar hyperbolic problems (both linear and scalar conservation laws), provided that the exponent pβ in the definition of the Jiang–Shu [G.S. Jiang, C.W. Shu, Efficient implementation of weighted eno schemes, J. Comput. Phys. 126 (1996) 202–228] nonlinear weights be taken as pβ=r, as originally proposed by Liu et al. [X.D. Liu, S. Osher, T. Chan, Weighted essentially nonoscillatory schemes, J. Comput. Phys. 115 (1994) 200–212], instead of pβ=2 (this is valid both for weno and wenom reconstructions), although the optimal value of the exponent is probably pβ(r)∈[2,r]. Then, we apply the family of very-high-order wenompβ=r reconstructions to the Euler equations of gasdynamics, by combining local characteristic decomposition [A. Harten, B. Engquist, S. Osher, S.R. Chakravarthy, Uniformly high-order accurate essentially nonoscillatory schemes iii, J. Comput. Phys. 71 (1987) 231–303], with recursive-order-reduction (ror) aiming at aleviating the problems induced by the nonlinear interactions of characteristic fields within the stencil. The proposed ror algorithm, which generalizes the algorithm of Titarev and Toro [V.A. Titarev, E.F. Toro, Finite-volume weno schemes for 3-D conservation laws, J. Comput. Phys. 201 (2004) 238–260], is free of adjustable parameters, and the corresponding rorwenompβ=r schemes are essentially nonoscillatory, as Δx→0, up to r=9, for all of the test-cases studied. Finally, the unsplit linewise 2-D extension of the schemes is evaluated for several test-cases. 相似文献
4.
通过求解2+1维de-Sitter时空中零测地线方程得到光线的轨迹方程,对轨迹方程进行分析发现其不存在封闭的轨迹解. 相似文献
5.
S. S. De 《International Journal of Theoretical Physics》2002,41(7):1291-1305
From a consideration of extended hadron structure in the microlocal anisotropic space-time, the mesonic and baryonic states with their internal quantum numbers such as strangeness, hypercharge, baryon number are constructed. The SU
3 baryonic multiplets of baryons with spin (j +
) are generated from the SU
3 mesonic multiplets of mesons with spin j. The meson–baryon mass differences are also derived here. The composite particle field of hadrons for the macroscopic space-time are obtained. In particular, the meson field and one particle meson state are considered here. These one particle hadron states of the macroscopic space-time also possess the quantum numbers (strangeness, hypercharge, etc.) which are regarded as the manifestations of the anisotropic nature of the microlocal space-time. The composite fields constructed here are usable in the reduction formulae of the S-matrix approach for strong interaction. 相似文献
6.
We use the hydrodynamic formulation of Scale Relativity Theory to analyze the TDGL equation. As a result, London equations come naturally from the system, when equating to zero the real velocity, the imaginary one turns real, the superconducting fluid act as a subquantum medium energy accumulator, the vector potential, the real and the imaginary velocity are all written in terms of the elliptic function. When solving the resulted system by means of WKBJ method, we get tunneling and quantization. In other words, scale transformation laws produce, on the motion equation of particles governed by the TDGL equation, under some peculiar assumptions, effects which are analogous to those of a “macroscopic quantum mechanics”. 相似文献
7.
Hydrodynamic properties for a class of nondiffusive particle systems are investigated. The method allows one to study local equilibria for a class of asymmetric zero-range processes, and applies as well to other models, such as asymmetric simple exclusion and misanthropes. Attractiveness is an essential ingredient. The hydrodynamic equations present shock wave phenomena. Preservation of local equilibrium is proven to hold away from the shocks. The problem of breakdown of local ergodicity at the shocks, which was investigated by D. Wick in a particular model, remains open in this more general setup. 相似文献
8.
Tai-PingLiu TommasoRuggeri 《应用数学学报(英文版)》2003,19(1):1-12
In shock wave theory there are two considerations in selecting the physically relevant shock waves.There is the admissibility criterion for the well-posedness of hyperbolic conservation laws.Another consideraztion concerns the entropy production across the shochs.The latter is natural from the physical point of view,but is not sufficient in its straightforward formulation,if the system is not genuinely nonlinear.In this paper we propose the principles of increasing entropy production and that of the superposition of shocks.These principles arc shown to be equivalent to the admissibility criterion. 相似文献
9.
新模式热电联产系统:联产供热的一个发展 总被引:4,自引:0,他引:4
1前言经济的迅猛发展,能源与水源的供需矛盾的突出,环保形势的严峻要求用能的“文明化”。文明用能应是跨世纪和新世纪用能战略的基本原则。文明用能的一个极重要方面就是对热能的文明利用问。热电联产是热能文明利用不可替代的途径。本文提出一种热电联产的新模式,旨在通过这种模式把联产供热规模化,大幅度地节约能源和水资源,减轻电能与热能的生产对环境的不利影响。最近中央提出的可持续发展战略,应成为我们今后技术研究的一个指导性方针。节约能源、水源和保护环境是这一战略的重要组成部分。在世界范围内,对节约资源保护环境问… 相似文献
10.