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991.
Based on a new intermediate transformation, a variable-coeFficient hyperbola function method is proposed.Being concise and straightforward, it is applied to the (2 1)-dimensional variable-coeFficient Broer-Kaup system. As a result, several new families of exact soliton-like solutions are obtained, besides the travelling wave. When imposing some conditions on them, the new exact solitary wave solutions of the (2 1)-dimensional Broer Kaup system are given. The method can be applied to other variable-coeFficient nonlinear evolution equations in mathematical physics. 相似文献
992.
GAOGuan-Qie CHENXian-Feng CHENYu-Ping WANGFei-Yu XIAYu-Xing 《理论物理通讯》2004,42(1):110-112
The formation of the dark spatial solitary wave in cascaded second harmonic generation processes is numerically studied based on the nonlinear-coupled equations. It is shown that the solitary wave exists when the effective three-order nonlinearity induced by cascaded second-order nonlinearity is negative. 相似文献
993.
BAICheng-Lin LIUXi-Qiang ZHAOHong 《理论物理通讯》2004,42(6):827-830
We study an approach to constructing multiple soliton solutions of the (3 1)-dimensional nonlinear evolution equation. We take the (3 1)-dimensional potential- YTSF equation as an example. Using the extended homogeneous balance method, one can find a Backlund transformation to decompose the (3 1)-dimensional potential-YTSF equation into a set of partial differential equations. Starting from these partial differential equations, some multiple soliton solutions for the (3 1)-dimensional potential-YTSF equation are obtained by introducing a class of formal solutions. 相似文献
994.
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997.
The properties of electromagnetic waves propagating inside isotropic or uniaxial dielectric media moving in an arbitrary direction are analysed. The scalar products of electromagnetic field vectors inside these moving media are investigated in the kEB system from Maxwell's equations and Lorentz-covariant constitutive relations. Several important equations are derived. They are useful in discussing problems such as the energy density and radiation pressure, which are of interest in theoretical studies and many application subjects. 相似文献
998.
A new discrete spectral problem is introduced and the corresponding hierarchy of the lattice soliton equations are derived by means of the trace identity. We find a new Darboux transformation of the lattice soliton equation, through which the explicit solutions are shown. 相似文献
999.
Form invariance and conserved quantities of Nielsen equations of relativistic variable mass nonholonomic systems 总被引:1,自引:0,他引:1 下载免费PDF全文
In this paper, the definition and criterion of the form invariance of Nielsen equations for relativistic variable mass nonholonomic systems are given. The relation between the form invariance and the Noether symmetry is studied.Finally, we give an example to illustrate the application of the result. 相似文献
1000.
The dispersive properties of a dielectric-rod loaded waveguide immersed in a magnetized annular plasma 总被引:4,自引:0,他引:4 下载免费PDF全文
Propagation properties of electromagnetic waves in a dielectric-rod waveguide immersed in a magnetized annular plasma are presented in this paper. The dispersion relations are derived and calculated. The results show that the dielectric-rod loading can make the structure less dispersive and the transmission frequency-band broadened. 相似文献