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41.
ZHU Jia-Min LU Zhi-Ming LIU Yu-Lu 《理论物理通讯》2008,49(6):1403-1406
One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some unknown parameters. The Jaulent-Miodek equations are used to illustrate effectiveness and convenience of this method, some new explicit exact travelling wave solutions have been obtained, which include bell-type soliton solution, kink-type soliton solutions, solitary wave solutions, and doubly periodic wave solutions. 相似文献
42.
郑永树 《应用数学和力学(英文版)》1981,2(5):613-623
In this paper we discuss singular perturbations of first boundary value problem for higher order elliptic equations of two parameter and obtain the asymptotic expression for the formal solution containing two-parameter as well as the estimation of its remainder term. These results are the extensions of (2) and (3). 相似文献
43.
Using an approach proposed in [3],we consider some linear and nonlinear problems forviscoelastic rods.Results in [1]for linear case are affirmed more elamentarily and simplyhere.We also treat linear problem with damping term and nonlinear problem with powernonlinearity Pu~3. Some new results are established. 相似文献
44.
顾卫华 《应用数学和力学(英文版)》1985,6(12):1205-1215
The formula of BEM suited to solve the problems of wave propagation in boundlessmedium is obtained from numerical treatment of Kirchhoff integral equation.Afer quotingthe coefficients of refraction and reflection of wave at surface or interface,the expression ofBEM which is suitable for the problems of wave propagation in multi-isotropic mediums isalso given. 相似文献
45.
董明德 《应用数学和力学(英文版)》1985,6(3):213-218
For Poiseuille flow the Orr-Sommerfeld equation is solved exactly. Regular solutions are obtained, thereby eigenvalue equation can be analyzed analytically and explicitly. The bifurcation solutions will be discussed subsequently. 相似文献
46.
47.
The solutions of the continuity equation and the equations of motion of the flow in the vicinity of a rotating disk have been established for an Ostwald fluid under steady-state conditions and in modulated flow around a mean value. Under steady-state conditions, the kinematics of the flow is scarcely dependent on the rheological parameters close to the disk, however, for n < 1 long-range effects have been put forward. For modulated flow, in the high-frequency range, a behaviour very different from that observed for a Newtonian fluid was found. In the low-frequency range an asymptotic solution has been proposed which is of special interest in mass transfer problems.Presented at the Second Conference of European Rheologists, Prague, June 17–20, 1986 相似文献
48.
余桑 《应用数学和力学(英文版)》1987,8(12):1115-1131
Despite its beauty and grandeur the theory of GR still appears to be incomplete in thefollowing ways:(1)It cannot accommodate the asymmetric total energy momentum tensor whoseasymmetry has been shown to exist in the presence of electromagnetism.(2)The law of angular momentum balance as an exact equation is not an automaticconsequence of the field equations as is the case with the law of linear momentum balance.(3)The four degrees of arbitrariness left by the contracted second Bianchi identitymakes a unique solution of the field equations unattainable without extra (unphysical)postulates.To answer the challenge posed by the above assertions we propose in this paper tocomplete Einstein’s theory by postulating the principle fibre bundle P[M,SU(2)]for theunderlying geometry of the 4-dimensional spacetime,where the structre group SU (2) isthe real representation of the special complex unitary group of dimension 2. SU (2) leavesconcurrently invariant the metric form dS~2=g_(αβ)dx~αdx~β and the fundamenta 相似文献
49.
Zhang Ju-ling 《应用数学和力学(英文版)》1994,15(1):81-91
A second order linear ordinary differential equation has been studied, and the complete expresson, of the formal uniformly
valid asymptotic solutions to the equation near turning point is obtained by using extended Airy function. 相似文献
50.