逆

Based on X-filtered LMS algorithm and -filtered LMS algorithm adaptive inverse control, we use a new variable step size LMS algorithm. Adding little computation, variable step size LMS algorithm can result in fast convergence speed and low residual error simultaneously. The adaptive feedback control can counteract the beginning error of the system. The adaptive disturbance canceler can best erase noises and disturbances.

在原来的X-滤波LMS算法自适应逆控制和-滤波LMS算法自适应逆控制方法的基础上，引入了新的变步长LMS算法，在计算量增加不多的前提下，能同时获得较快的收敛速度和较小的稳态误差；引入自适应的反馈补偿控制克服了被控系统的直流零频漂移，使控制系统在初开始工作阶段快速收敛；还引入自适应扰动消除器，它能最大限度的消除扰动。

To obtain the function and imbedding properties about relative countable tightness spaces,in this paper the question whether the relative countable tightness space can be adversely preserved by a closed map is studied by means of function and imbedding theories.

为了得到相对可数紧度空间的映射及嵌入性质，借助映射方法和紧化理论讨论了相对可数紧度空间被闭映射逆保持问题及嵌入紧空间问题，得到了相对可数紧度空间被闭映射逆保持的一个充分条件、局部紧的可数紧度空间可嵌入紧空间的几个充分条件以及某一类局部紧空间在任意紧化中不具有可数紧度等结果。

A numerical calculation program is written up for the various solution methods in this paper and the program is being used in various aspects of inverse problem of environmental hydraulics, including inverse problem in reverse process of one-dimensional unstable diffusion, inverse problem in reverse process of convection-diffusion, inverse problem for the dispersion coefficient in water quality model, The inverse problem of coefficient identification for nonlinear Boussinesq equation, parameter identification inverse problem for water quality model, the inversion of parameter of BOD-DO water model, the inverse problem of the source of convection-diffusion, identification of the steady-state permeability for two dimensional isotropic medium, two-dimensional steady inverse problem of convection-diffusion and parameter identification inverse problem for two-dimensional parabolic equation, etc.

对本文提出的各种算法，编制了数值计算程序，并把它应用于环境水力学反问题诸多领域，包括污染物一维非恒定扩散逆过程反问题，对流扩散方程逆过程反问题，河流水质纵向弥散系数反问题，非线性Boussinesq方程反问题，河流水质多参数识别反问题，BOD-DO水质模型参数反演问题，对流—扩散方程源项反问题及二维恒定各向同性介质渗透系数反问题，二维定常对流——扩散方程及二维抛物型方程参数控制反问题等。

This article presented a new fast algorithm of Moore-Penrose inverse for an m×n symmetric Loewner-type matrix with full column rank by forming a special block matrix and studied its inverse. Its computation complexity was O+O(n^2), but it was O(mn^2)+O(n^3) by using L(superscript +)=L(superscript TL^(-1)L.

论文通过构造特殊分块矩阵并研究其逆矩阵，给出了秩为n的m×n对称Loewner矩阵Moore-Penrose逆的快速算法，该算法的计算复杂度为O+O(n^2)，而通过L=L(上标 TL^(-1)L计算的复杂度为O(mn^2)+O(n^3)。

In this paper, an improved inverter side passive filter was proposed on the bases of analysis of common-mode and differential-mode voltage, and a detailed design procedure of parameters was given.

本文通过对PWM逆变器驱动电机系统产生的共模以及差模电压分析，提出了一种改进型的逆变器端无源滤波器，并给出了参数的设计方法。

In order to solve the application problem of conduction heating machining, this project investigates some problems, such as dynamic characteristics of heating power, features of circuit current and voltage, arc discharge states and so on. It also studies control characteristics of Uni-phase or Tri-phase Direct Current Power Supply and Inverse Switch Power Supply. A High Frequency Inverse Switch Commutate Power Supply is developed.

为了解决导电加热切削的应用问题，从加热电源的动态性能和回路的电流、电压特性及电弧放电状态等方面进行研究，分析比较了单、三相交直流电源和逆变开关电源的特点和控制特性，研制了高频逆变开关整流电源。

The extracted P-wave is reverse-time extrapolated and imaged with a P-velocity model using a finite difference solution of the scalar wave equation, the extracted S-wave is reverse-time extrapolated and imaged similarly, but with an S-velocity model, and converted S-wave data requires a polarity correction prior to migration to ensure constructive interference between data from adjacent source.

在模型中，每个网格点的纵、横波成像时间，为震源到该网格点的纵波初至时间。利用纵波速度模型和声波传播方程的有限差分解，对反射纵波进行逆时延拓和成像，利用横波速度模型和声波传播方程的有限差分解，对转换横波进行逆时延拓和成像，并在偏移前进行极性校正。

In the third section,we study the relationship between the APOTP for continuous map / on a compact metric space X and that for the lift map / of / on a covering space X and show that has the APOTP if and only if has the APOTP.

在第四节中，我们研究逆极限空间上移位映射的APOTP，讨论紧致度量空间上连续映射APOTP与逆极限空间上移位映射APOTP间的关系。

The present paper proposed one kind of numerical control single-phase inversion structure, in detail elaborated the system parameter design, the rectification work basic principle of work, the contravariant basic principle and the SPWM sine pulse width modulation.

本论文提出了一种数字控制的单相逆变器结构，详细论述了系统的参数设计，整流工作的基本工作原理，逆变的基本原理及SPWM正弦脉冲宽度调制。

This article introduces a new contravariant bridge circuit in the power source of the medium friquency induction furnace,analyzes the necessity of using R-C for protecting the thyris-tors.

介绍一种新型晶闸管中频感应电炉的逆变电桥，分析了对该电桥逆变晶闸管采用阻容保护电路的必要性。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。