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91.
We investigate the dynamics of the wave packet formed by two codirected strongly interacting waves propagating in a medium with cubic nonlinearity. We obtain a soliton solution of the nonlinear Schrödinger equation in the degenerate case where the wave packet is described by a single partial momentum. In the nondegenerate case, we use the variational method to find the equation for the pulse duration, which turns out to be analogous to the equation for the coordinate in the Kepler problem. Solving it, we find the dependences of the pulse duration on the propagation distance in the cases of finite and infinite propagation regimes. 相似文献
92.
We construct separation variables for the Kovalevskaya–Goryachev–Chaplygin gyrostat for arbitrary values of the parameters. We show that different separation variables can be constructed for the same integrable system if different integrals of motion are chosen. 相似文献
93.
Mathematical Notes - 相似文献
94.
We study the complex Ginzburg–Landau equation with zero Neumann boundary conditions on a finite interval and establish that this boundary problem (with suitably chosen parameters) has countably many stable two-dimensional self-similar tori. The case of periodic boundary conditions is also investigated. 相似文献
95.
L.E. Payne 《Journal of Mathematical Analysis and Applications》2003,284(1):283-293
We consider some initial-boundary value problems for the linear and nonlinear heat equation where the gradient of the solution is prescribed on the boundary. Assuming that a solution exists, we obtain bounds for the solution and its gradient by maximum principle arguments or by means of differential and integral inequalities. 相似文献
96.
M. Benchohra 《Journal of Mathematical Analysis and Applications》2003,286(1):307-325
In this paper, we shall establish sufficient conditions for the existence of integral solutions for some nondensely defined evolution impulsive differential inclusions in Banach spaces with nonlocal conditions. 相似文献
97.
Ryo Ikehata 《Journal of Mathematical Analysis and Applications》2003,288(2):803-818
We generalize a previous result of Ikehata (Math. Methods Appl. Sci., in press), which studies the critical exponent problem of a semilinear damped wave equation in the one-dimensional half space, to the general N-dimensional half space case. That is to say, one can show the small data global existence of solutions of a mixed problem for the equation utt−Δu+ut=|u|p with the power p satisfying p∗(N)=1+2/(N+1)<p?N/[N−2]+ if we deal with the problem in the N-dimensional half space. 相似文献
98.
Melvyn B. Nathanson 《Journal of Number Theory》2003,103(2):214-233
For the quantum integer [n]q=1+q+q2+?+qn−1 there is a natural polynomial multiplication such that [m]q⊗q[n]q=[mn]q. This multiplication leads to the functional equation fm(q)fn(qm)=fmn(q), defined on a given sequence of polynomials. This paper contains various results concerning the construction and classification of polynomial sequences that satisfy the functional equation, as well open problems that arise from the functional equation. 相似文献
99.
ZHOU Yi 《数学年刊A辑(中文版)》2003,(3):293-302
This paper considers the following
Cauchy problem for semilinear wave equations in $n$ space
dimensions
$$\align
\square\p &=F(\partial\p ),\\p (0,x)&=f(x),\quad \partial_t\p (0,x)=g(x),
\endalign$$
where $\square =\partial_t^2-\triangle$ is the wave operator, $F$ is
quadratic in $\partial\p$ with
$\partial =(\partial_t,\partial_{x_1},\cdots ,\partial_{x_n})$.
The minimal value of $s$ is determined such that the above
Cauchy problem is locally well-posed in $H^s$. It turns out that
for the general equation $s$ must satisfy
$$s>\max\Big(\frac{n}{2}, \frac{n+5}{4}\Big).$$
This is due to Ponce and Sideris (when $n=3$) and Tataru (when $n\ge
5$). The purpose of this paper is to supplement with a proof in the
case $n=2,4$. 相似文献
100.
By means of a Carleman estimate, we obtain several observability inequalities by internal observation for hyperbolic equations with lower-order terms. Also, we apply our observability results to an exact controllability problem and an inverse wave source problem. 相似文献