查询词典 transient stability

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。

Expansions in orthogonal functions is used to solve the Orr-Sommerfeld equation in studies of the linear stability of parallel flow. For the plane Poiseuille flow the critical Reynold number is given accurately. Furthermore, the Blasius flow which is considered locally parallel has been studied, and the neutral stability curves, which are very important for the stability study, are given.

对于平行流的托尔明—施里希廷(Tollmien-Schlichting，T-S)波的线性稳定性，采用谱方法求解平面Poiseuille流的Orr-Sommerfeld方程，得到了精确的临界雷诺数；并研究了局部平行假设下的Blasius边界层流动，分别给出对稳定性研究至关重要的中性稳定性曲线。

The article points out the gas flow stability in the borehole should be divided into quality stability and thermal stability.

文章提出气井在井筒流动的稳定性应分为质量稳定和热力稳定的问题。

At the same time, the variational stability of bounded variation solutions at the effect of perturbation and non-perturbation for the impulsive differential system are discussed, the Ljapunov type theorems for variational stability and asymptotically variational stability for impulsive differential systems are established.

同时，讨论了在无扰动和有扰动的情况下，这类固定时刻脉冲微分方程有界变差解的变筹稳定性，建立了此类微分系统有界变差解变差稳定性和渐近变界稳定性的两个Ljapunov型定理。

First introduction whole wave commutate electric circuit of work principle, immediately after introduction the electric capacity filter the function characteristics of an electric circuit, and in the electric circuit adoption exaltation stability, exaltation temperature stability and limit flow a type over flow protection electric circuit of concrete measure with insure an electric circuit safety stability of work.

首先介绍了全波整流电路的工作原理，接着介绍了电容滤波电路的性能特点，然后引入了具有放大环节和辅助电源的串联可调式稳压电源，并在电路中采用了提高稳定度，提高温度稳定性及限流型过流保护电路的具体措施，以确保电路安全稳定的工作。

Engine room counting fee management application, project structure and expansion solution guidebook A PC product need analysis: Engine room application besides need towards function had special request outside, other summarize to have 4:00:(1) PC fundamental that PC that stability, engine room use is up is everyday 24 hours request for be placed inning openning the machine and circulating the appearance, stability towards PC having more and strictly, then request PC at any time high low temperature start, stanza can manage, power supply manage, inside memory manage and keep on worked deathless machine very and strictly, this is not is what DIY can make to, these factors must be in the product system design inside factor that consider, at the same time at the factor that the machine produce adopt a 48 hour development test the machine can discover latent influence system stability;(2) PC of can manage the sex, engine room as if teach Teach the profession's electronics classroom, and management engine room as if management teacher to electronics teacher, and this is the PC network management, namely on-line management, for example early the machine of many sets proceed together the OS to install, application the procedure install, hardware management, usage supervise and control and report to the police the etc.

机房应用除了对性能有特殊要求之外，其它的需求概括起来有4点：（1）PC的稳定性，机房用的PC基本上是每天24小时处于开机及运行状态，对PC的稳定性有更加严格的要求，即对PC 随时高低温启动、节能管理、电源管理、内存管理以及持续工作不死机的要求非常严格，这并非是DIY所能做到的，这些因素必须是在产品系统设计中考虑的因素，同时在机器生产时采用48小时动态考机才能发现潜在的影响系统稳定性的因素；（2）PC的可管理性，机房如同教育行业的电子教室，对机房的管理如同对教师对电子教师的管理，这就是PC的网络管理，即在线管理，例如初始化多台机器并行OS安装、应用程序安装、硬件管理、使用监控以及报警等管理功能，针对机房PC，专门开发机房管理软件，实现对机房PC的管理；（3）易用性要求，机房PC如同傻瓜PC，在客户端不需要安装、设置，只须开机，满足易用性要求；（4）健康要求：静电、电磁辐射指标、显示器防眩、键盘鼠标抗菌设计及符合人体公学设计。

Major content of this work includes five aspects as follows:(1). Oxygen sensitive materials had been prepared by carrier covalence method, and the preparation mechanism of the materials had been investigated by FI-IR, SEM, and the detection experiment of oxygen. Then through the detection of oxygen, the sensitivity and stability had been estimated, and it was studied that the properties of materials would be affected by the various factors.(2). Oxygen sensitive materials had been prepared by carrier covalence-cross linking method, and the preparation mechanism of the materials had been investigated by FI-IR, SEM, and the detection experiment of oxygen. Then through the detection of oxygen and spectrophotometer, the sensitivity and stability had been estimated, and it was studied that the properties of materials would be affected by the various factors.(3). For the detection of gaseous oxygen, the fiber optical sensor on basis of oxygen sensitive materials had a respond time of 10s, detection limit of 5ppmand detection precision of 0.5%. The sensor had good repeatability and stability, a less delay and at least 1 year life-span.

本论文主要包括以下五个方面的内容：(1)载体共价法制备氧敏感材料：通过红外光谱、扫描电镜图谱和氧测试实验探讨该氧敏感材料的制备机理，通过氧测试实验评价该氧敏感材料的氧敏感性和稳定性，同时研究了各种因素对该氧敏感材料性能的影响(2)载体共价—交联法制备氧敏感材料：通过红外光谱、扫描电镜图谱和氧测试实验探讨该氧敏感材料的制备机理，通过氧测试实验和分光光度计评价该氧敏感材料的氧敏感性和稳定性，同时研究了各种因素对该氧敏感材料性能的影响(3)氧敏感材料在光纤气态氧传感器中的应用：该传感器的响应时间为10s，检测下限为5ppm，检测精度为0.5％，具有较好的重复性和稳定性，迟滞较小，使用寿命至少为1年，适合各种环境下气态氧浓度的检测。

In-plane stability capacity of I-section aluminum alloy bars under eccentric compressions was investigated with FEA program of ANSYS. The stability of the bars with different slenderness ratio and eccentricity was analyzed and the influence of initial crookedness and residual stresses on the stability was emphatically discussed.

动用ANSYS软体对常用的铝合金压型材偏心压杆的平面内稳定承载力进行了研究，分析了不同长细比和偏心率杆件的稳定性能，并讨论了残余应力与初弯曲对杆件承载力的影响。

This diesis not only summarized and induced the classification of the slope and the influence factors of slope stability, but also summarized and classified the basic and new theories and methods of slope stability analysis, and then try to understand thoroughly and extensively the breakage mechanism and analytical theories and methods of slope stability for choosing the most suitable analytical theory and method of the engineering example research.

本文不仅对边坡的分类和影响边坡稳定性的因素进行归纳和总结，而且对边坡稳定性分析的基本理论与方法以及不断涌现出的新理论新方法进行整理、归纳和分类，力图对边坡变形破坏机制和边坡稳定性分析的理论与方法具有较为全面和深入的认识，为工程实例的研究确定适合的分析理论和方法。

According to the demand of high magnetic field power supply, reference is increased with a set ramp rate and stops at a set stable value, so reference system is composed of digital setting and digit to analog converting circuit. But the stability of reference is mostly guaranteed by the performance of D/A circuit, so D/A circuit is particularly studied in reference system. The scheme of D/A circuit, the selection of DAC and its voltage reference, hardware anti-jamming design and PCB design are discussed in detail, and software of remote control and PLC are discussed in brief. Zero-flux DC current transformer well satisfies the demands of the high stability of Load current detection unit, so the principle of zero-flux DC current transformer is analyzed; in the mean time a project which detects the long term stability is designed. During 8 hours, analog signal which is detected with high precision digit multimeter is recorded in computer at 1HZ frequency by GPIB communication. The drift error source and related parameters are explained in the compare-amplify part. Detailed subtraction circuit is designed; also amplifier chip and periphery components are selected and verified according to the theory of error analysis.

根据强磁场电源的需求，参考源应按照软件设定的斜率逐渐上升到设定稳态值，则参考源系统应由数字给定和数模转换电路两大部分组成，而参考源的稳定度主要依靠完成数模转换功能的模拟电路的性能来保证，因此本文对参考源系统的研究以数模转换电路为重点，分别从电路方案的确定、数模转换芯片及其基准电压源的选取和验证、电路板硬件抗干扰和PCB设计几方面进行了论述，然后对数字给定部分的远控组态和PLC程序设计作了简要介绍；采用零磁通原理的直流电流转换器很好地满足了对负载电流检测单元高稳定度的需求，本文详细分析了零磁通检测的原理，并在选定此种类型电流转换器的基础上设计了一套检测长期稳定度的方案，8小时内以1秒为采样周期，通过计算机Labview程序和高精度数字电压表的GPIB通讯，将被高精度数字电压表数字化后的模拟信号采样值连续记录至计算机中；比较放大环节简要阐述了漂移产生的原因和相关参数指标，确定了具体的减法电路形式，并根据误差分析理论对运算放大器和外围元器件进行了选取和验证。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。