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901.
In this work, we present the interaction solutions and abundant exact solutions for the new (3+1)-dimensional generalized Kadomtsev-Petviashvili equation based on the Hirota''s bilinear form and a direct function. The obtained interaction solutions contain the interaction between the rational function and the $\tanh$ function and the interaction between the rational function and the $\cos$ function. The dynamical properties of these resulting solutions are analyzed and shown in three-dimensional plots, corresponding contour graphs and plane figures.  相似文献   
902.
在线性压电陶瓷本构关系和裂纹边界绝缘的框架下,用超奇异积分方程的方法对椭圆类片状裂纹问题进行了重新研究.超奇异积分方程中的未知位移间断和电势间断近似地表示为基本密度函数与多项式之积,其中基本密度函数反映了椭圆片状裂纹前沿电弹性场的奇异性,而多项式在均布载荷作用下可用一个常数来表达.引入椭球坐标系后,得到了均布载荷作用下未知位移间断和电势间断的解析解.使用这些解析解和电弹性场强度的定义,得到了裂纹前沿Ⅰ型、Ⅱ型和Ⅲ型应力强度因子以及电位移强度因子的精确表达式.法向均布载荷作用下的结果与现有精确解完全一致,切向均布载荷作用下的结果则尚未见有其它报道.  相似文献   
903.
According to the constitutive relationship in linear piezoceramics, elliptical crack problems in the impermeable case are reconsidered with the hypersingular integral equation method. Unknown displacement and electric potential jumps in the integral equations are approximated with a product of the fundamental density function and polynomials, in which the fundamental density function reflects the singular behavior of electroelastic fields near the crack front and the polynomials can be reduced to a real constant under uniform loading. Ellipsoidal coordinates are cleverly introduced to solve the unknown displacement and electric potential jumps in the integral equations under uniform loading. With the help of these solutions and definitions of electroelastic field intensity factors, exact expressions for mode Ⅰ, mode Ⅱ and mode Ⅲ stress intensity factors as well as the mode Ⅳ electric displacement intensity factor are obtained. The present results under uniform normal loading are the same as the available exact solutions, but those under uniform shear loading have not been found in the literature as yet.  相似文献   
904.
The Painlev(e) integrability and exact solutions to a coupled nonlinear Schrodinger (CNLS) equation applied in atmospheric dynamics are discussed. Some parametric restrictions of the CNLS equation are given to pass the Painleve test. Twenty periodic cnoidal wave solutions are obtained by applying the rational expansions of fundamental Jacobi elliptic functions. The exact solutions to the CNLS equation are used to explain the generation and propagation of atmospheric gravity waves.  相似文献   
905.
The Painleve integrability and exact solutions to a coupled nonlinear Schrodinger (CNLS) equation applied in atmospheric dynamics are discussed. Some parametric restrictions of the CNLS equation are given to pass the Painleve test. Twenty periodic cnoidal wave solutions are obtained by applying the rational expansions of fundamental Jacobi elliptic functions. The exact solutions to the CNLS equation are used to explain the generation and propagation of atmospheric gravity waves.  相似文献   
906.
The Schrodinger equation for a particle in the V-shaped potential decorated by a repulsive or attractive Dirac delta function interaction at the center is solved, demonstrating the crucial influence of point interaction on the even-parity states of the original system without decoration. As strength of the attraction increases, the ground state energy falls down without limit; and in limit of infinitely large attraction, the ground state approaches a singular state. Our analysis and conclusion can be readily generalized to any one-dimensional system a particle interacts with symmetrical potential plus the Dirac delta function interaction at the center.  相似文献   
907.
We investigate the exact nonstationary solutions of a two-component Bose Einstein condensate which compose of two species having different atomic masses. We also consider the interesting behavior of the atomic velocity and the flow density. It is shown that the motion of the two components can be controlled by the experimental parameters.  相似文献   
908.
The exact solutions of the generalized (2+1)-dimensional nonlinearZakharov-Kuznetsov (Z-K) equation are explored by the method of the improved generalized auxiliary differential equation. Many explicit analytic solutions of the Z-K equation are obtained. The methods used to solve the Z-K equation can be employed in further work to establish new solutions for other nonlinear partial differential equations.  相似文献   
909.
In this paper, we use the classical Lie group symmetry method to get the Lie point symmetries of the (2+1)-dimensional hyperbolic nonlinear Schrödinger (HNLS) equation and reduce the (2+1)-dimensional HNLS equation to some (1+1)-dimensional partial differential systems. Finally, many exact travelling solutions of the (2+1)-dimensional HNLS equation are obtained by the classical Lie symmetry reduced method.  相似文献   
910.
宋佩君  吕新友  刘继兵  郝向英 《中国物理 B》2010,19(5):50503-050503
By using a two-mode mean-field approximation,we study the dynamics of the microcavities containing semiconductor quantum wells.The exact analytical solutions are obtained in this study.Based on these solutions,we show that the emission from the microcavity manifests periodic oscillation behaviour and the oscillation can be suppressed under a certain condition.  相似文献   
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