查询词典 differential method

Based on the fundamental theory of impulsive differential systems, employing Green formula, Gauss divergence theorem, Jensen inequality and Gronwall-Bellman inequality with impulse, we discuss the oscillation of impulsive partial differential systems by adopting reduction to absurdity and the stability in via of comparison theorem, respectively. Especially, we take an in-depth study on the oscillation of neutral impulsive parabolic systems and the stability of a class of nonlinear impulsive partial differential equations and obtain some useful conclusions.

本学位论文以脉冲微分系统基本理论为基础，利用反证法的分析方法和比较定理，结合Green公式、Gauss散度定理、Jensen不等式、含脉冲的Gronwall-Bellman不等式以及相关数学工具研究了脉冲偏微分系统的振动理论和稳定性理论，特别对中立型脉冲时滞抛物系统的振动性和一类非线性脉冲偏微分系统的稳定性作了较为深入的研究，给出了一些有用的结论。

Firstly,by using the estimating methodfor the compact embedding operators(from weighted Sobolev space to the weighted〓space),we obtain a necessary and sufficient condition for the discreteness of thespectrum of certain differential operators.Secondly,based on the property of thespectrum of difinitizable operators on the Krein space,we consider the left definitedifferential equations with middle deficiency indices,and give a completecharacterization for self-adjoint(J-self-adjoint)differential operators in theindefinite inner product space 〓.Especially,we prove that all the J-self-adjoint differential operators are definitizable.

我们首先运用加权Sobolev空间到加权〓空间嵌入算子紧性的判别方法，证明一类加权自伴微分算子具有离散谱的充要条件；然后，基于Krein空间上可定化算子谱的性质，对于具中间亏指数的左定型微分方程，建立其相应的微分算式在不定度规空间〓上所生成自伴算子的完备性刻画（特别证明了J-自伴微分算子具有可定化性）。

This course mainly contents real number muster and function, limit of number sequence, limit of function, continuity, derived number and differential, differential mean value theorem and its application, completeness of real number, integral, series(including positive series and Fourier series), multiple- differential, double integral, integral with parameter, curve integral, camber integral and so on.

理解和掌握《数学分析》的概念、理论和方法，对于学生加深理解数学的基本思想和方法，培养抽象思维能力和逻辑思维能力，提高数学素养具有重要的意义。主要内容包括：实数集和函数，数列极限，函数极限，连续性，导数和微分，微分中值定理及其应用，实数完备性，积分、级数(包括幂级数、Fourier级数)、多元微分学、重积分、含参变量积分、曲线积分、曲面积分等。

Chapter 4 discusses the stability of a class of nonlinear impulsive partial differential equations. The main idea is translating the stability of the considered nonlinear impulsive partial differential equation into that of the corresponding linear impulsive ordinary differential equation via Gronwall-Bellman inequality with impulse on the basis of comparison theorem.

第四章基于比较定理，主要利用含脉冲的Gronwall-Bellman不等式初步讨论了脉冲偏微分系统的稳定性，将一类非线性脉冲偏微分方程的稳定性化归为线性脉冲常微分方程的稳定性，为将脉冲常微分方程稳定性的有关结论推广到脉冲偏微分方程提供了理论依据并奠定了基础。

Firstly, the existence and uniqueness of the solution for neutral stochastic functional differential equations with infinite delay under the uniformly Lipschitz condition, linear grown condition and contractive condition can be directly derived; And the moment estimate of the solution and the estimate for error between the approximate solution and the accurate solution can be both given; If the uniformly Lipschitz condition is replaced by the local Lipschitz condition, the existence and uniqueness theorem can be gained; Meanwhile, the existence and uniqueness of the global solution in the interval 0,+∞ can also be obtained; Secondly, L~p-exponential estimate of the solution for neutral stochastic functional differential equations with infinite delay can be studied; At length, the theorem of the local solution about neutral stochastic functional differential equations with infinite delay only under the local Lipschitz condition and the contractive condition can be established.

首先，在一致Lipschitz条件，线性增长条件和压缩性条件下，直接得到了具无限时滞中立型随机泛函微分方程解的存在惟一性，并给出了解的矩估计，近似解与精确解之间的误差估计；将一致Lipschitz条件替换为局部Lipschitz条件，也得到了具无限时滞中立型随机泛函微分方程解的存在惟—性，同时，也给出了在整个区间0，+∞上具无限时滞中立型随机泛函微分方程解的存在惟一性定理；其次，也讨论了具无限时滞中立型随机泛函微分方程解的L~p指数估计；最后，在局部Lipschitz条件和压缩性条件下，建立了具无限时滞中立型随机泛函微分方程局部解的存在惟一性定理。

Our analysis framework relies on the reflected Backward Stochastic Differential equation approach.We characterize the value functions of the noncallable bonds in terms of the reflected Backward Stochastic Differential equation,Then the relationship between the value function of convertible bonds and reflected backward stochastic differential equations with single reflect is built at the same time,and provide the optimal conversion strategy for bondholders.2:We get the value of non-callable convertible bonds by numerical methods.

探讨了可转换债券的最优停时价值与带反射边界倒向随机微分方程解的关系，在市场完备，公司价值只包括股权和可转债这两种权益等各种假定下，给出不可赎回可转换债券的价值函数，证明了不可赎回可转换债券的最优停时问题的解是存在的，同时给出了其最优的转换策略。2：通过数值方法求解不可赎回可转换债券的价值。

Using PH linearization ,the nonlinear partial differential equation was transformed into linear partial differential equation,and then,by introducing a complex function,it was further transformed into a set of two linear differential equations.

应用 PH线性化方法，将非线性偏微分方程转化为线性偏微分方程，引入复函数将复常数偏微分方程变为两个线性实常数微分方程组，并采用小参数迭代法进行求解，近似求得了螺旋槽内气体动压分布的解析解。

In studing methods,partial func-tional differential equations sum up the theories and methods of ordinary differentialequations,partial differential equations,the semigroup theory and the fixed-pointtheory in functional analysis and the basic concepts,theories and methods suit-able for the partial differential equations with delay are formed.

偏泛函微分方程在研究方法上综合了常微分方程的理论方法和泛函分析中算子半群、不动点理论以及偏微分方程的理论方法，并形成了以时滞为基本特征的泛函微分方程的基本概念、理论和方法。

Carleman不等式及其在最优控制问题中的应用.Optimal control theory of distributed parameter systems mainly includes: Pontryagin's maximum principle; controllability; Hamilton-Jacobi equation (i.e., dynamic programming equation); time optimal control, etc.In this dissertation, we establish Pontryagin's maximum principle of optimal control problems governed by some nonlinear differential equations (parabolic differential equations, elliptic differential equations and 3-dimensional Navier-Stokes equations), which in particular could have local solut...

在这篇博士论文中，我们建立了非线性微分方程(包括抛物型微分方程，椭圆型微分方程以及3维Navier-Stokes方程)最优控制问题的庞特里雅金最大值原理，特别地，这些方程可能只有局部解或存在多解(我们称这样的系统为非适定系统，相应的最优控制问题为非适定最优控制问题)，以及适定的非线性发展方程最优控制问题的庞特里雅金最大值原理；我们研究了phase-field系统的时间最优控制问题以及Boussinesq系统的局部内可控性。

Linear differential equations of the principle of superposition theory of linear differential equations play an important role, especially in solving linear differential equations of the nature and structure of play to solve the problem of reducing the complexity and difficulty of the role.

请帮忙翻译一下摘要，跪谢线性微分方程解的叠加原理在线性微分方程理论中占有重要地位，尤其是在解决线性微分方程解的性质和结构问题中起到了降低解决问题的复杂度以及难度的作用。

Diabetes is a social disease that affects several million people worldwide.

糖尿病是一个社会性疾病，全世界有数百万人罹患此病。

I'll call you on Friday to see if we can reschedule our luncheon meeting at your convenience.

我星期五会给您打电话在您方便的时候我们重新安排我们的午餐约会。