《专业英语》PPT课件.ppt

Chapter 8,Process Automatic Control System,核心单词和词组,AM：Amplitude Modulation FM：Frequency Modulation Signal Magnitude ：信号幅度 RF：radio frequency：无线电频率，射频 Radio Frequency Identification , RFID:射频识别 Audible frequency：音频 Broadcast station：广播电台，广播站 Radiate：发射，广播, 辐射 Submerge：沉浸，没入水中 Ice bath：冰点槽 thermostatic bath：恒温槽,核心单词和词组,Linearizer：n.线性化电路 Line, Linear, Linearize reproduction：再生，再现，复制，繁殖 Be concerned with：参与，干预 Feedback：反馈 Feedforward：前馈 Bimetallic：双金属的 Set point dial：设定刻度，给定刻度 Set point：设定值，给定值 Thermostat：温度调节装置，自动调温器,句子分析,The input can be speech, music, or data that is produced at one location and transmitted efficiently over long distances, permitting faithful recovery of the original input.,句子分析,The letters AM stand for Amplitude Modulation. They mean that the amplitude or magnitude of a radio frequency (RF) signal is caused to vary according to the magnitude of a lower-frequency signal (audio, corresponding to audible frequencies),句子分析,The function of transmitter in an AM broadcast system is to accept the input signal from an input device (microphone), use this signal to control the amplitude of a radio frequency signal (each broadcast station is assigned its own radio frequency), and drive the output device (the antenna) with a radio frequency current to produce electromagnetic waves radiating into space.,句子分析,The functions of the receiver are to amplify or increase the strength of the relatively weak signal obtained from the antenna, to filter or select the desired radio frequency signal from the signals of all other broadcast stations, to recover the audio signal from the amplitude variations of the radio frequency signal, and to drive a loudspeaker with this audio signal.,句子分析,The pair of thermocouple junctions, one attached to the object whose temperature is to be measured, the other submerged in an ice bath (to establish a stable reference point), presents to the processor a voltage that depends on the temperature difference between the object to be measured and the ice bath.,句子分析,In measurement system, therefore, one expects to be concerned with locating and removing any small errors that might be added to the signal at each step of the processing sequence.,8.2 Introduction to Process Control,A host of ：许多，一大群 Regulate：调节 Self-regulation：自动调节 Reference value：参考值，标准值 Set point：设定值，给定值 Tank：槽，箱，坦克 Level: 水位，水平，等级 Square root：平方根 Flow rate：流速，流量,核心单词和词组,Modification：修改，改进 Sight tube：瞄准管，液位指示管 Controlled variable：被控变量，被控量 Controlling variable：控制变量，控制量 Evaluate：估算 Mechanical linkage ：机械连接 Servomechanism：伺服机构，伺服系统 Tracking control system：跟踪控制系统 Stir：搅拌,8.3 Computer Process Control,Relay bank：