数学

Thin film equations; nonlinear cross-diffusion systems; two-dimensional nonlinear reaction-diffusion equations; invariant subspace method; invariant sets

基础科学，数学，数学分析薄膜方程；非线性交错扩散方程组；二维非线性反应扩散方程；不变子空间方法；不变集

Heat equation; finite element method; inverse problem; probe method; size estimate

基础科学，数学，数学分析热方程；有限元；反问题；探测法；大小估计

Three common mathematic models are always employed to predict the growth of regional or urban population,including exponential function,inverse hyperbolic function,and logistic function.

预测人口增长的数学模型通常采用3种函数，即指数函数、Logistic函数和双曲函数。3种模型的数学根源都在于二阶Bernoulli式微分方程，它们是不同的生长条件下的Logistic方程的特解。

In feedforward control, the hysteresis nonlinearity of the piezoceramic actuator is modeled using the Preisach model and a neural network architecture using input-output data mapping as the inverse function of Preisach model is utilized.

前向补偿控制器设计方面，先以布列谢希之数学模式来模式化压电陶瓷的磁滞特性，再由实测值求得模式内之参数值，并应用类神经网路结构取代Preisach数学模式的反涵数以作为前向控制器之用。

Generalized Bott-Duffin inverse; Moore-Penrose inverse; operator matrix quantum effect; sequential product

基础科学，数学，数学分析广义Bott-Duffin逆；广义逆；算子矩阵；量子效应；序列积

In chapter 2,nonlinear model and linear model of the single inverted pendulum are given.

第2章给出了一级旋转式倒立摆系统的非线性数学模型和线性化数学模型。

A detailed analysis of the main circuit introduction, control method and working principle of the direct-drive wind energy conversion system are given to introduce the two important parts a of this paper: First part is the control method of the multiple boost convertor, the important instantaneous current control method of this paper is given through the analysis of the main circuit structure, control method and working principle. Then a steady-state analysis for low-frequency, a high-frequency component analysis, and a closed-loop tracking performance analysis for dynamic response are provided to analyze the method proposed; And the second part is the control method of invertor.

在系统变流器整体结构分析的基础上，引出本文重点研究的两个变流环节的控制：第一部分是系统升压斩波器的控制，通过分析相关主电路结构、原理，建立了数学模型，引出本文重点研究的瞬时值控制策略的概念和具体实现，并对升压斩波器的瞬时值控制策略进行了详细的高频、低频模型分析和稳态、动态性能分析；第二部分是系统并网逆变器的控制，通过对逆变器主电路的数学建模和控制要求分析，研究了并网逆变器的瞬时值控制策略，包括电感电流控制内环和直流电压控制外环的具体设计和实现方法。

This paper tries to found the model of network control system based on the PROFIBUS-DP ISOCHRONE SYNCHRONIZATION mode with the linear system theory, and proves the ISOCHRONE SYNCHRONIZATION mode is an ideal disperse control system.

本文尝试运用线性系统理论建立PROFIBUS-DP等时同步模式数学模型，证明可以作为理想的离散数学系统处理。

Based on raw materials, this thesis begins with Escher's exploration of mathematical methods, analyzes his regular division of the plane with preliminary symmetric principles-concepts about symmetry and isometry transformation, rotation, ref...

本文基于原文资料的整理，以埃舍尔对数学方法的探索为切入点，运用数学中初步的几何原理——对称概念及等距变换概念(旋转、平移、反射、滑移反射)对埃舍尔的周期性空间分割图案进行了详实的分析，进而对艺术设计的形式中感性与理性、艺术设计与科学等关系进行探讨。

Considering the characteristics of KEM and complicated soils in practice, one rule is given to describe soils borderline and borderline's points, and so the problem to delineate soils and ground seepage is solved.

针对KEM和实际工程中复杂土体的特点，本文建立了一套土层边界线编号和每条边界线上点号的规则，解决了复杂土体内各土层的数学描述问题以及土体内地下水渗流的数学描述问题。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。