电阻

PART 1 Electrical and Electronic Engineering Basics UNIT 1 A UNIT 2 A UNIT 3 A UNIT 4 A UNIT 5 A UNIT 6 A UNIT 7 A Electrical Networks ———————————— 3 B Three-phase Circuits The Operational Amplifier ——————————— 5 Logical Variables and Flip-flop —————————— 8 Power Semiconductor Devices —————————— 11 Types of DC Motors —————————————15 AC Machines ———————————————19 Electric Power System ————————————22 B Transistors B Binary Number System B Power Electronic Converters B Closed-loop Control of DC Drivers B Induction Motor Drive B Power System Automation PART 2 Control Theory UNIT 1 A B UNIT 2 A UNIT 3 A UNIT 4 A The World of Control ————————————27 Stability and the Time Response ————————— 30 The Root Locus ————————————— 32 The Transfer Function and the Laplace Transformation —————29 B Steady State————————————————— 31 B The Frequency Response Methods: Nyquist Diagrams ————— 33 The Frequency Response Methods: Bode Piots ————— 34 B Nonlinear Control System 37 UNIT 5 A Introduction to Modern Control Theory B B B PART 3 B B B State Equations Optimum Control Systems Artificial Neural Network Computer Control Technology 42 43 44 Fundamentals of Computer and Networks The Applications of Computers 46 40 38 UNIT 6 A Controllability, Observability, and Stability UNIT 7 A Conventional and Intelligent Control UNIT 1 A Computer Structure and Function UNIT 2 A Interfaces to External Signals and Devices UNIT 3 A PLC Overview PACs for Industrial Control, the Future of Control 1 UNIT 4 A Fundamentals of Single-chip Microcomputer 49 B B PART 4 B B B B PART 5 B B B B PART 6 Understanding DSP and Its Uses Embedded Systems Design Process Control 50 52 53 Fundamentals of Process Control UNIT 5 A A First Look at Embedded Systems UNIT 1 A A Process Control System UNIT 2 A Sensors and Transmitters Final Control Elements and Controllers PID Controllers and Other Controllers Control Panels Control Based on Network and Information Evolution of Control System Architecture Stability of NCSs with Network-induced Delay Virtual Manufacturing—A Growing Trend in Automation Enterprise Resources Planning and Beyond Synthetic Applications of Automatic Technology UNIT 3 A P Controllers and PI Controllers UNIT 4 A Indicating Instruments UNIT 1 A Automation Networking Application Areas UNIT 2 A Fundamental Issues in Networked Control Systems UNIT 3 A Fundamentals of the Database System UNIT 4 A Concepts of Computer Integrated Manufacturing UNIT 1 A Recent Advances and Future Trends in Electrical Machine Drivers B B B System Evolution in Intelligent Buildings A General Introduction to Pattern Recognition Electric Vehicles UNIT 2 A Industrial Robot UNIT 3 A Renewable Energy 2 UNIT 1 A

电路 电路或电网络由以某种方式连接的电阻器，电感器和电容器等元件组成。如果网络不包含能源，如电池或发电机，那么就被称作无源网络。换句话说，如果存在一个或多个能源，那么组合的结果为有源网络。在研究电网络的特性时，我们感兴趣的是确定电路中的电压和电流。因为网络由无源电路元件组成，所以必须首先定义这些元件的电特性。就电阻来说，电压-电流的关系由欧姆定律给出，欧姆定律指出：电阻两端的电压等于电阻上流过的电流乘以电阻值。在数学上表达为： u=iR (1-1A-1)式中 u=电压，伏特；i =电流，安培；R =电阻，欧姆。纯电感电压由法拉第定律定义，法拉第定律指出：电感两端的电压正比于流过电感的电流随时间的变化率。因此可得到：U=Ldi/dt 式中 di/dt =电流变化率，安培/秒； L =感应系数，享利。电容两端建立的电压正比于电容两极板上积累的电荷 q 。因为电荷的积累可表示为电荷增量 dq 的和或积分，因此得到的等式为 u=，式中电容量 C 是与电压和电荷相关的比例常数。由定义可知，电流等于电荷随时间的变化率，可表示为 i = dq/dt。因此电荷增量 dq 等于电流乘以相应的时间增量，或 dq = i dt，那么等式(1-1A-3)可写为式中 C =电容量，法拉。

There are many kinds of sensors , and the gas-sensor is an important kind, whose theory is to make use of the variable of resistance under the sensitive gas condition, resulting in the change of electricity variable in the circuits.

传感器的类型有很多，而其中很重要的一种就是电阻型气敏传感元件，它的原理就是利用敏感电阻在气体中电阻率改变，从而引起电阻的变化进而通过电路中电学量的改变来测量敏感气体的存在。

In addition, the voltage-current characteristic of linear resistive components is the general solution of Clairaut equation, and the voltage-current characteristic of non- linear components is the singular solution of Clairaut equation.

论文摘要：本文讨论了任意伏安特性电阻元件满足的基本微分方程以及非线性电路的功率匹配问题的几个定理，指出任意伏安特性电阻元件均满足非线性一阶的clairaut方程，并且，线性电阻元件的伏安特性是clairaut 方程通解，而非线性电阻元件的伏安特性是clairaut 方程的奇解。

In the electrical measurements, the resistivity matches well to the value obtained from bulk single AlCuCo decagonal quasicrystal samples when the temperature is higher than 86K.

在电子输运性质研究中，电阻率的高温电阻率是与块状样品的大小一致，低温电阻率测量中，首次发现了电阻率极小。

This article introduces some petrophysical study achievements of oil/gas-bearing formation log interpretation in recent 10 years:(1) The formation of low-resistivity pay zones in Bohai Bay is due to the fact that sea-water drilling mud invaded into oil/gas-bearing formation; Complex dual pore texture of pay zones with high average water saturation and additional conductivity of the clay minerals.

介绍了近10年来油气层测井评价方面的岩石物理研究成果：①渤海湾地区低电阻油层形成机理有：滩海地区海水钻井液在低幅度油气藏背景下深侵入，使油层视电阻率成倍下降；油层具有复杂的双组孔隙系统，平均含水饱和度高使电阻率变低；油层的黏土矿物附加导电现象造成低电阻。

And fixed resistor has RT-carbon film,RJ-Metal Film, RX-Wirewound resistors.

而固定电阻常用、常见的有RT型碳膜电阻、RJ型金属膜电阻、RX型线绕电阻。

Using Hankel digital filter algorithm and inverse spine interpolation algorithm to simulate electromagnetic fields of the horizontal layers , we contrast the calculational Cagniard apparent resistivity with its results and field experimentation.

利用汉克尔数值滤波算法和逆样条插值算法对水平层状电磁场进行正演计算，并与计算的卡尼亚视电阻率的对比和野外试验结果表明：该方法的结果在远区等价卡尼亚电阻率，在近区和过渡带则明显地改善了卡尼亚电阻率的非波场区场畸变，从而能更好地接近基底的真电阻率，更形象地反映了地下介质的垂向电性变化。

The surface resistance and volume resistance of sample were measured by ZC-36 Megohmmeter and the corresponding resistivity could be calculated. The tensile strength and elastic modulus of specimen were characterized by tensile machine.

采用ZC36型高阻位电阻计测定样品的表面电阻和体积电阻，并计算出相应的电阻率，本论文还测定不同含量MWNTs的样品的拉伸强度及弹性模量等性能，分析了不同含量的MWNTs对复合材料导电性和力学性能的影响，并总结出其规律。

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武汉康达电气有限公司-电气仪表，内冷发电机绝缘特性测试仪，电子式指针绝缘电阻表，指针绝缘/导通电阻表，接地电阻测量仪，大地网地阻仪，等电位连接电阻测量仪，防雷元件测试仪

At last of the paper, it's studied the relationship between the resistance of the pins of the pincushion 2D PSD and Gear theorem, and find the way to get the boundary resistance and square resistance of sensitive area from the resistance of the pins which can get the position nonlinearity rapidly.

最后，研究了枕型二维PSD的极间电阻与Gear定理之间的关系，可由具体器件的极间电阻确定其单位长度的边界电阻与光敏区方块电阻，从而可以用Gear定理来判别器件的位置线性度，克服了试片法以一概全的缺点。

I'm strongly against the death penalty — it's an eye for an eye.

我不赞成死刑——这是以牙还牙的报复行为。

And to get you the support you need, we're enlisting all elements of our national power: our diplomacy and development, our economic might and our moral suasion, so that you and the rest of our military do not bear the burden of our security alone.

并给你们所须的支援，我们正徵召国家所有各种的力量：我们的外交及发展，我们的经济力量与道德劝说，所以你们与其他军人不须要孤独地负起国家安全的责任。