《專業(yè)英語(yǔ)》PPT課件

Chapter 8Process Automatic Control System 核心單詞和詞組n AM：Amplitude Modulationn FM：Frequency Modulationn Signal Magnitude ：信號(hào)幅度n RF：radio frequency：無(wú)線電頻率，射頻n Radio Frequency Identification , RFID:射頻識(shí)別n Audible frequency：音頻n Broadcast station：廣播電臺(tái)，廣播站n Radiate：發(fā)射，廣播, 輻射n Submerge：沉浸，沒入水中n Ice bath：冰點(diǎn)槽 n thermostatic bath：恒溫槽 核心單詞和詞組n Linearizer：n.線性化電路 n Line, Linear, Linearizen reproduction：再生，再現(xiàn)，復(fù)制，繁殖n Be concerned with：參與，干預(yù)n Feedback：反饋n Feedforward：前饋n Bimetallic：雙金屬的n Set point dial：設(shè)定刻度，給定刻度 n Set point：設(shè)定值，給定值n Thermostat：溫度調(diào)節(jié)裝置，自動(dòng)調(diào)溫器 句子分析nThe 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. data or input? 句子分析nThe 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n 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n 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n 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. Who? 句子分析n 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 Controln A host of ：許多，一大群n Regulate：調(diào)節(jié)n Self-regulation：自動(dòng)調(diào)節(jié)n Reference value：參考值，標(biāo)準(zhǔn)值n Set point：設(shè)定值，給定值n Tank：槽，箱，坦克n Level: 水位，水平，等級(jí)n Square root：平方根n Flow rate：流速，流量 核心單詞和詞組n Modification：修改，改進(jìn)n Sight tube：瞄準(zhǔn)管，液位指示管n Controlled variable：被控變量，被控量n Controlling variable：控制變量，控制量n Evaluate：估算n Mechanical linkage ：機(jī)械連接n Servomechanism：伺服機(jī)構(gòu)，伺服系統(tǒng)n Tracking control system：跟蹤控制系統(tǒng)n Stir：攪拌 8.3 Computer Process Controln Relay bank：繼電器組n Hierarchical structure：層次結(jié)構(gòu)，分級(jí)結(jié)構(gòu)n initiated：引發(fā)的，引導(dǎo)的n Process-initiated Interrupt：過(guò)程引導(dǎo)的中斷n Timer-initiated actions：定時(shí)器引導(dǎo)的操作n Polling：輪流檢測(cè)