共查询到20条相似文献，搜索用时 31 毫秒
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研究了一类扰动Vakhnemko方程.给出了改进的渐近方法.首先, 对原模型系统对应的典型方程得到对应的行波解.其次, 引入一个泛函, 建立迭代关系式,将求解非线性问题转化为求解一系列的迭代序列.然后, 逐次地求出对应的解的近似式, 最后,得到了原扰动Vakhnemko模型行波解的任意次精度的近似展开式,并讨论了它的精度.
关键词：
泛函
行波解
Vakhnemko方程 相似文献
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We construct an asymptotic theory that describes the kinetics of first-order phase transitions. The theory is a considerable
refinement of the well-known Lifshits-Slezov theory. The main difference between the two is that the Lifshits—Slezov theory
uses for the first integral of the kinetic equation an approximate solution of the characteristic equation, which is valid
in the entire range of sizes except for the blocking point, i.e., it uses a nonuniformly applicable approximation. At the
same time, the behavior of the characteristic solution near the blocking point determines the asymptotic behavior of the size
distribution function of the nuclei for the new phase. Our theory uses a uniformly applicable solution of the characteristic
equation, a solution valid at long times over the entire range of sizes. This solution is used to find the asymptotic behavior
of all basic properties of first-order phase transitions: the size distribution function, the average nucleus size, and the
nucleus density.
Zh. éksp. Teor. Fiz. 113, 2193–2208 (June 1998) 相似文献
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We develop an asymptotical control theory for one of the simplest distributed oscillating systems, namely, for a closed string under a bounded load applied to a single distinguished point. We find exact classes of string states that admit complete damping and an asymptotically exact value of the required time. By using approximate reachable sets instead of exact ones, we design a dry-friction like feedback control, which turns out to be asymptotically optimal. We prove the existence of motion under the control using a rather explicit solution of a nonlinear wave equation. Remarkably, the solution is determined via purely algebraic operations. The main result is a proof of asymptotic optimality of the control thus constructed. 相似文献
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The corresponding solution for a class of disturbed KdV equation is considered using the analytic method. From the generalized variational iteration theory, the problem of solving soliton for the corresponding equation translates into the problem of variational iteration. And then the approximate solution of the soliton for the equation is obtained. 相似文献
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We analytically examine the asymptotic solution of gluon evolution equation in terms of the ‘double scaling variables’ρ andσ of perturbative QCD and find the approximate lower bounds on these, above which the solution is considered to be valid. Comparison
of this asymptotic solution is made with the fit obtained from data and the estimated lower bound onρ is nearly equal to our analytical finding. To analyze the data below the lower bound onρ, other analytical solutions of gluon evolution equation are to be used which depend highly on the inputx-distributions of gluon to study the physics at low-x of HERA range. 相似文献
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