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51.
The q-p phase-space distribution function is a popular tool to
study semiclassical physics and to describe the quantum aspects of a system. In this paper by using the pure state density operator formula of the Husimi operator
Δh(q,p;κ)=|p,q〉κκ〈p,q| we deduce the Husimi function of the excited squeezed vacuum state. Then we study the behavior of Husimi distribution graphically. 相似文献
52.
The absorption spectrum of the 16O3 isotopologue of ozone has been recorded in the 7000-7920 cm−1 region by high sensitivity CW-Cavity Ring Down Spectroscopy. This report is devoted to the analyses of the 7065-7300 cm−1 region dominated by the ν1 + 2ν2 + 5ν3 and ν1 + 5ν2 + 3ν3 A-type bands at 7130.8 and 7286.8 cm−1 respectively. 289 transitions were assigned to the ν1 + 2ν2 + 5ν3 band. The corresponding line positions were modeled with an effective Hamiltonian involving Coriolis resonance interactions between the (1 2 5) upper state and the (4 4 0), (0 2 6) and (6 1 0) dark states, and an anharmonic resonance interaction with the (2 0 5) state. The very strong interaction (up to 50% mixing of the wavefunctions) between the (1 2 5) and (6 1 0) states leads to the observation of two extra lines of the 6ν1 + ν2 band due to a resonance intensity transfer. 213 transitions of the ν1 + 5ν2 + 3ν3 band were assigned and modeled taking into account a Coriolis resonance interaction with the (3 6 0) state.We take the opportunity of the present work to report the analysis of the very weak 4ν2 + 4ν3 B-type band at 6506.1 cm−1 which was assigned from previously recorded CRDS spectra. 286 transitions were modeled using the effective Hamiltonian approach.The dipole transition moment parameters of the three analyzed bands were determined by a least-squares fit to the measured line intensities. For the three studied band systems, the effective Hamiltonian and transition moment operator parameters were used to generate line lists provided as Supplementary Materials. 相似文献
53.
云连英 《浙江大学学报(理学版)》2009,36(3):254-258
给出了基于q-整数的Stancu算子Ln(·,q),同时研究了该算子的一些基本性质.首先,利用q-Stancu算子作用于某一函数f(x)以后Ln(f,q;x)与f(x)变号数的关系,得到了该算子的保形性定理.其次,通过精细的不等式放缩,该算子作用于一般的连续函数后收敛于一极限算子,而不像一般算子那样收敛于函数本身,并用光滑模刻画了其收敛速度. 相似文献
54.
杨云苏 《南昌大学学报(理科版)》2009,33(5):1
在Banach空间中引进了一类(H,η)增生算子,利用预解算子技巧,建立了一个Ishikawa迭代,并证明了此迭代算法产生的变分包含的解的存在与唯一性。其结果是近期相关结果的改进与推广。 相似文献
55.
董明德 《应用数学和力学(英文版)》1984,5(1):1029-1040
The dynamic stability of a thin plate in supersonic flow based on 2-dimensional linear theory leads to the study of a new problem in mathematical physics: complex eigenvalue prob-lem for a non-self-adjoint fourth-order integro-differential equation of Volterra’s type.Exact solutions of the aeroelastic system is obtained. In contrast to various approximate analyses, our critical curve agrees satisfactorily with experimental data, being free from divergence in the low supe’rsonic region. Moreover, we observe some notable physical behaviors: (1) mutual separation of flutter and vacuum frequency spectrums, (2) degeneracy of critical Mach number. The present method may be generalized in solving the supersonic flutter for 3-dimensional airfoil model as well as blade cascade in turbo-generator. 相似文献
56.
Kazuhiro Matsuo 《Journal of statistical physics》1978,18(6):535-555
A projection operator method is presented, which provides the most efficient way for calculating the stationary behavior of nonlinear Brownian motion. A continued-fraction expansion of the Fourier-Laplace transform of the displacement correlation function or the spectral density is used. This method utilizes a successive optimization procedure on the nonlinear terms and includes the method of statistical linearization as the lowest order approximation. A systematic way to calculate the continued fraction numerically up to sufficient order for convergence is developed, which enables us to obtain the spectral density of a system previously uncomputable.Numerical computations of the spectral density of a nonlinear oscillator with a double-well potential are presented and compared with the results obtained by statistical linearization.This work was supported in part by the National Science Foundation under Grant CHE 75-20624. 相似文献
57.
李艳红 《浙江大学学报(理学版)》2014,41(2):127-131
通过减弱公理化条件给出新拟乘算子, 并按照拟乘运算针对实函数正(负)部建立了广义拟Sugeno模糊积分. 依据演化的确界概念获得了该积分的3种表达形式, 并给出了其等价表示及其证明. 最后, 通过实例验证了该广义拟Sugeno模糊积分3种等价表示的正确性. 相似文献
58.
本文在REDUCE语言环境下,利用公理化方法建立了一个“抽象算符演算”系统.使REDUCE系统可用于抽象的算符演算,逆演算;用于Laplace变换,逆变换及解微分方程,推导公式,以及验证有关定理等. 相似文献
59.
吴慧卓 《纯粹数学与应用数学》2003,19(1):16-21
典型的进化策略受自然进化过程的启发而成为求解全局优化问题的重要方法。传统的ES变异算子作为一个主要的进化技术是建立在正态分布的随机变量基础上的,本文提出了基于指数分布的进化策略由于采用了新的变异算子有效地减少了产生探试解的成本,从而优于传统的进化策略。 相似文献
60.
We study the max-plus equation
(∗) 相似文献