共查询到18条相似文献,搜索用时 125 毫秒
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在求一类非线性波方程行波解时,先将有关的非线性常微分方程在其Poincaré相平面上作定性分析,然后再区别情况求积分,从而得到了各式各样的行波解。
关键词: 相似文献
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用函数和方程变换将二阶耦合线性微分方程组转化为一阶非线性类椭圆方程,并给出了一次和二次限定变换下方程组的Jacobi椭圆函数解析解,所得结果修正了文献中超导特例的近似解,进一步肯定了超导边界层电场的存在性.
关键词:
微分方程
Jacobi椭圆函数
解析解
超导 相似文献
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扩展了最近提出的F展开方法以构造非线性演化方程更多的精确解,即将F展开法中的一阶非线性常微分方程和单变量的有限幂级数代之以类似的一阶常微分方程组和两个变量的有限幂级数,这两个变量是一阶常微分方程组的解分量.作为例子,用扩展的F展开法解非线性Schroedinger方程,得到了很丰富的包络形式的精确解,特别是以两个不同的Jacobi椭圆函数表示的解.显然,扩展的F展开方法也可以解其他类型的非线性演化方程. 相似文献
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H. M. Ito 《Journal of statistical physics》1984,37(5-6):653-671
We present a linearization procedure of a stochastic partial differential equation for a vector field (X
i
(t,x)) (t[0, ),xR
d
,i=l,...,n):
t
X
i
(t,x)=b
i
(X(t, x)) +D, X
i
(t, x) +
i
f
i
(t, x). Here is the Laplace-Beltrami operator inR
d
, and (f
i
(t,x)) is a Gaussian random field with f
i
(t,x)f
j
(t,x) =
ij
(t – t)(x – x). The procedure is a natural extension of the equivalent linearization for stochastic ordinary differential equations. The linearized solution is optimal in the sense that the distance between true and approximate solutions is minimal when it is measured by the Kullback-Leibler entropy. The procedure is applied to the scalar-valued Ginzburg-Landau model in R1 withb
1(z) =z - vz
3. Stationary values of mean, variance, and correlation length are calculated. They almost agree with exact ones if 1.24 (
2
1
4
/D
1
1/3:=
c
. When
c
, there appear quasistationary states fluctuating around one of the bottoms of the potentialU(z) = b
1(z)dz. The second moment at the quasistationary states almost agrees with the exact one. Transient phenomena are also discussed. Half-width at half-maximum of a structure function decays liket
–1/2 for small t. The diffusion term
x
2
X accelerates the relaxation from the neighborhood of an unstable initial stateX(0,x) 0. 相似文献
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In this paper, we improve some key steps in the homogeneous balance method (HBM), and propose a modified homogeneous balance
method (MHBM) for constructing multiple soliton solutions of the nonlinear partial differential equation (PDE) in a unified
way. The method is very direct and primary; furthermore, many steps of this method can be performed by computer. Some illustrative
equations are investigated by this method and multiple soliton solutions are found. 相似文献
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A lattice Boltzmann model with an amending function forsimulating nonlinear partial differential equations 下载免费PDF全文
This paper proposes a lattice Boltzmann model with an
amending function for one-dimensional nonlinear partial
differential equations (NPDEs) in the form $u_t+\alpha uu_{xx}+\beta u^n u_x+\gamma u_{xxx}+\xi u_{xxxx}=0$. This model is
different from existing models because it lets the time step
be equivalent to the square of the space step and derives higher
accuracy and nonlinear terms in NPDEs. With the Chapman--Enskog
expansion, the governing evolution equation is recovered correctly
from the continuous Boltzmann equation. The numerical results
agree well with the analytical solutions. 相似文献
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A new variable coefficient algebraic method and non-travelling wave solutions of nonlinear equations 下载免费PDF全文
In this paper, a new auxiliary equation method is presented of constructing more new non-travelling wave solutions of nonlinear differential equations in mathematical physics, which is direct and more powerful than projective Riccati equation method. In order to illustrate the validity and the advantages of the method, (2+1)-dimensional asymmetric Nizhnik-Novikov-Vesselov equation is employed and many new double periodic non-travelling wave solutions are obtained. This algorithm can also be applied to other nonlinear differential equations. 相似文献
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In this paper, analytical solutions to time-fractional partial differential equations in a multi-layer annulus are presented. The final solutions are obtained in terms of Mittag-Leffler function by using the finite integral transform technique and Laplace transform technique. In addition, the classical diffusion equation (α=1), the Helmholtz equation (α→0) and the wave equation (α=2) are discussed as special cases. Finally, an illustrative example problem for the three-layer semi-circular annular region is solved and numerical results are presented graphically for various kind of order of fractional derivative. 相似文献
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Using functional derivative technique in quantum field theory, the algebraic dynamics approach for solution of ordinary differential
evolution equations was generalized to treat partial differential evolution equations. The partial differential evolution
equations were lifted to the corresponding functional partial differential equations in functional space by introducing the
time translation operator. The functional partial differential evolution equations were solved by algebraic dynamics. The
algebraic dynamics solutions are analytical in Taylor series in terms of both initial functions and time. Based on the exact
analytical solutions, a new numerical algorithm—algebraic dynamics algorithm was proposed for partial differential evolution
equations. The difficulty of and the way out for the algorithm were discussed. The application of the approach to and computer
numerical experiments on the nonlinear Burgers equation and meteorological advection equation indicate that the algebraic
dynamics approach and algebraic dynamics algorithm are effective to the solution of nonlinear partial differential evolution
equations both analytically and numerically.
Supported by the National Natural Science Foundation of China (Grant Nos. 10375039, 10775100 and 90503008), the Doctoral Program
Foundation of the Ministry of Education of China, and the Center of Nuclear Physics of HIRFL of China 相似文献
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A class of nonlinear Schrödinger-type equations, including the Rangwala-Rao equation, the Gerdjikov-Ivanov equation, the Chen-Lee-Lin equation and the Ablowitz-Ramani-Segur equation are investigated, and the exact solutions are derived with the aid of the homogeneous balance principle, and a set of subsidiary higher order ordinary differential equations (sub-ODEs for short). 相似文献