查询词典 parabolic partial differential equation

In Chapters 3 and 4, we investigate the existence of periodic solutions of a class of second order functional differential equation and a class of third order functional differential equation, respectively, and obtain new sufficient conditions of their existence result of periodic solutions under growth conditions and linear growth condition, respectively.

第三章与第四章分别研究了一类二阶泛函微分方程及一类三阶泛函微分方程的周期解存在性，分别在增长条件及线性增长条件下，获得了这两类方程周期解存在性的新的充分条件，与文献中已知结果比较，我们所讨论的方程更为一般，所得结果较简洁且易于验证。

In Chapters 3 and 4, we investigate the existence of periodic solutions of a class of second order functional differential equation and a class of third order functional differential equation, respectively, and obtain new sufficient conditions of their existence result of periodic solutions under growth conditions and linear growth condition, respectively. Compared with some known results in the literature, the equations discussed by us are more general, and our results are concise and easy to be verified.

第三章与第四章分别研究了一类二阶泛函微分方程及一类三阶泛函微分方程的周期解存在性，分别在增长条件及线性增长条件下，获得了这两类方程周期解存在性的新的充分条件，与文献中已知结果比较，我们所讨论的方程更为一般，所得结果较简洁且易于验证。

In this paper we contribute the general integral formula of second order linear differential equation with constant coefficients by means of decreasing order So we can integrate directly to solve this kind differential equation .

本文通过降阶法给出了求二阶常系数线性微分方程通解的方法，并根据特征根的不同情形给出了具体的通解公式，即可通过积分直接求微分方程的通解。

Applying the Hermite polynomial expansion, this integral-differential equation is creatively transformed into deterministic differential equation.

创造性地使用Hermite多项式展开，将确定性的积分——微分方程转换为确定性的微分方程。

The integral inequality is a useful tool when we study the stability theory of differential equation, especially when we study the stability, the estimate of solution and the boundedness of differential equation.

在研究微分方程稳定性理论中，尤其在探讨微分方程的稳定性，解的估计及有界性的过程中，积分不等式是一强有力的工具。

In this paper, the author investigate the oscillation of a class of second-order linear differential equation s with impulses, revealing the relation between this and the non linear differential equation s with impulses in Oscillation.

摘要研究一类二阶线性脉冲微分方程解的振动性，揭示了此类方程与相应的非脉冲方程在振动性方面的联系。

Throush the interlace series type linear differential equation,coefficient containing three negative number of times,power function and arrangement number can be changed into the linear differential equation of successive integral.

通过把系数含有负三次幂函数与排列数的交错级数型线性微分方程化为可逐次积分的线性微分方程，找出了求这类方程通解的方法与理论，把所得定理给出了严格的证明，并将其推广，同时通过实例介绍了它的应用。

The singular differential equation has developed on the basis of nonlinear functional analysis, because it can explain a lot of natural phenomenal, more and more mathematicans are devoting their times to the study of sigular differential equation.

以非线性泛函分析为基础而发展起来的奇异微分方程理论因其能很好的解释自然界中的各种各样的自然现象而倍受关注。

Of the fundamental matrix in (2) satisfies the differential equation =A , it follows that the matrix = itself satisfies the matrix differential equation Because its column vectors are linearly independent, it also follows that the fundamental matrix is nonsingular, and therefore has inverse matrix .

基本矩阵的求解由于（2）中的基本矩阵的列向量满足微分方程A，进而这个矩阵本身就满足矩阵微分方程。

A important result is the one-order expression of AR Yt = DYt-1 + E, from paralleling a high-order differential equation transformation into a one-order differential equation system, the one-order expression exposes that the AR is only a certain more-multivariable power series processAnd, if a process is described as an AR, the sufficient and necessary condition is the spectrum norm A of the coefficient matrix D less than one.

作者用高阶微分方程化一阶微分方程组的方法，获得多元弱平稳序列p阶自回归模型的一步滑动平均表达式，证明了AR的是一个更高维的幂级数的线性过程，从而，说明了AR关于序列依概率成立的充要条件是：该模型更高维的幂级数的线性过程的表达式中系数矩阵D的谱范数λ＜1。

Researches reveal that students who suffer from corporal punishment tend to resort to violence in their future life.

研究表明遭受过肉体惩罚的孩子倾向于在他们今后的人生中使用暴力。

Total sugar of sarcocarp and chlorophyll of pericarp increased firstly, and then decreased afterward along with altitude; Titratable acidity, ascorbicacid and anthocyanin of pericarp were increased along with altitude; The content of protein increased firstly and decreased afterward along with altitude; Carotenoid of pericarp were decreased along with altitude.

果肉总糖和果皮叶绿素含量随海拔高度升高先升高后降低；可滴定酸、维生素C和果皮花青苷含量均随海拔升高而升高；蛋白质在1720m处最大，1420m处最小；果皮类胡萝卜素随海拔升高而降低。