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使用一种简化的准离散多重尺度法,研究了具有非线性基底势的一维离散非线性晶格的孤波解, 表明孤波能够在这种一维非线性晶格链中存在,而且非线性基底势对孤波的载波频率、群速度、振幅等动力学性质都将产生影响。 另一方面,我们还对非线性动力学方程进行了数值求解, 发现用简化的准离散多重尺度法得到的近似解与精确的计算机数值计算结果符合得较好。 相似文献
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基于一般的浅水波方程, 根据大尺度正压大气的特点, 得到无量纲的控制大尺度大气的动力学非线性方程组. 利用多尺度法, 由无量纲的动力学方程组导出了扰动位势的非线性控制方程. 采用椭圆方程构造该扰动位势控制方程的解, 获得了扰动位势和速度的多周期波与冲击波(爆炸波) 并存的解析解. 扰动位势的解表明经向和纬向具有不同周期和波长的周期波, 且都受纬向孤波的调制; 速度的解表明大尺度大气流动存在气旋和反气旋周期性分布的现象.
关键词:
浅水波方程
大尺度正压大气
解析解
非线性波 相似文献
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A. D. Smirnov 《Russian Physics Journal》1972,15(12):1730-1735
Nonlinear spinor equations are derived in the paper by the nonlinear symmetry-group representation method. The basic field transforms according to the linear spinor representation of the orthochronous Lorentz group Lt. The internal symmetry group Gr is realized as a group of nonlinear transformations of the field . The invariant nonlinear spinor equations constituting the group Gr are found in terms of the covariant derivative. The group SU(2) is considered as an example.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 49–55, December, 1972.The author thanks D. D. Ivanenko and D. F. Kurdgelaidze for stimulating discussions and support. 相似文献
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Nicholas Andrew Alexander 《Journal of sound and vibration》2010,329(8):1137-3728
Analytical expressions are determined for the nonlinear resonant frequency (or natural frequency) of the fundamental lateral mode of a pile. A pile with a floating toe, with and without pile cap is considered in this paper. The influence of a nonlinear soil spring model that varies with depth and a nonlinear damping model that is strain amplitude dependent is considered. A non-dimensional equation of motion for the system dynamics is derived from an energy based formulation. This equation is a Duffing's type nonlinear differential system that has nonlinear damping. Harmonic balance with numerical continuation is employed to determine the nonlinear resonance curves of the system. Comparison with some experimental results is made. 相似文献
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Adelbert Owyoung 《Optics Communications》1976,16(2):266-271
A two-beam nonlinear interferometric technique is described whereby the amplitude and sign of both the real and imaginary parts of the nonlinear susceptibility χ3 may be determined. Moreover, this technique permits an extremely precise determination of the electronic and molecular contributions to χ3. Hence, we ascertain the electronic fraction of the Kerr constants of CS2 and C6H6 to be 12.7 ± 1.1% and 19.8 ± 0.8%, respectively. These results provide a basis for the comparison of nonlinear refractivity and frequency-mixing measurements in these materials and an accurate means for the absolute calibration of a variety of measurements of χ3. 相似文献
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S. O. Konorov A. A. Ivanov D. A. Akimov A. V. Yakimanskii A. A. Podshivalov A. N. Petrov N. N. Smirnov V. N. Ivanova V. V. Kudryavtsev I. M. Sokolova M. V. Alfimov A. M. Zheltikov 《Optics and Spectroscopy》2005,99(1):131-136
The polarization properties of second harmonic and sum-frequency signals generated by femtosecond laser pulses in films of polymers containing covalent groups of an azobenzothiazole chromophore polarized by an external electric field are investigated. It is shown that the methods of polarization nonlinear optics make it possible to determine the structure of oriented molecular dipoles and reveal important properties of the motion of collectivized π electrons in organic molecules with strong optical nonlinearities. The polarization measurements show that the tensor of quadratic nonlinear optical susceptibility of chromophore fragments oriented by an external field in macromolecules of the noted azopolymers has a degenerate form. This is indicative of a predominantly one-dimensional character of motion of collectivized π electrons along an extended group of atoms in such molecules. 相似文献
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The inverse spectral method is a nonlinear Fourier transform method for solving certain equations. Here, we emphasize that such transforms should be considered in their own right. We also elucidate further the connection between the Fourier transform and inverse spectral methods by establishing that linear equations can also be solved through the inverse spectral method. 相似文献
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By considering the cross phase modulation (XPM) between the two orthogonal poparization components,the nonlinear birefringence and nonlinear polarization evolution (NPE) in highly-nonlinear fiber (HNLF),as well as the unequal evolutions of the state of polarization (SOP) between the clockwise (CW) and counter-clockwise (CCW) waves in a nonlinear amplifying loop mirror (NALM) are analyzed. It is pointed out that the traditional cosine expression is no longer valid for the power transmission of NALM due to uncompleted interference under the high power condition. The analytical expression considering NPE effect is derived, and the experimental result is presented. 相似文献
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On the investigation of nonlinear waves of the Hirota and the Maxwell–Bloch equation in nonlinear optics 下载免费PDF全文
In this paper, considering the Hirota and Maxwell-Bloch (H-MB) equations which is governed by femtosecond pulse propagation through two-level doped fibre system, we construct the Darboux transformation of this system through linear eigenvalue problem. Using this Daurboux transformation, we generate multi-soliton, positon, and breather solutions (both bright and dark breathers) of the H-MB equations. Finally, we also construct the rogue wave solutions of the above system. 相似文献
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We treat the nonlinear phase shift response in the weak perturbation limit as a linear digital filter that can be synthesized into the values of its poles and zeros and mapped onto an optical architecture. This procedure results in a significant enhancement in the nonlinear sensitivity with a response that is robust to frequency changes within the filter passband. A precompensation technique can be used to reduce distortions under strongly driven nonlinear operation to achieve a larger phase shift. We also show that nonlinear sensitivity improves with increasing filter group delay and can be increased within constant linear bandwidth by use of higher-order filters. 相似文献
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We consider a one-dimensional modified complex Ginzburg-Landau equation, which governsthe dynamics of matter waves propagating in a discrete bi-inductance nonlineartransmission line containing a finite number of cells. Employing an extended Jacobielliptic functions expansion method, we present new exact analytical solutions whichdescribe the propagation of periodic and solitary waves in the considered network. 相似文献