科技英语课件Unit1-20+Exercises

科技英语课件ExercisesHMILYYLIMH1UUnniitt11EExxeerrcciisseess((11))TTrraannssllaatteetthheeffoolllloowwiinnggsseenntteenncceessiinnttooCChhiinneessee..1.Aswithseriesresonance,thegreatertheresistanceinthecircuitthelowertheQand,accordingly,theflatterandbroadertheresonancecurveofeitherlinecurrentorcircuitimpedance.对于串联谐振，电路中的电阻愈大Q值就愈低，相应地线路电流或电路阻抗的谐振曲线也就愈平、愈宽。2.Awirecarryingacurrentlooksexactlythesameandweighsexactlythesameasitdoeswhenitisnotcarryingacurrent.一根带电的导线其外表与重量都与不带电导线完全一样。3.Clickmouseonthewaveformanddragittochangethepulserepetitionrate,ordirectlyenteranewvalueoftheperiodintheprovideddialoguebox,whilekeepingthepulsewidthunchanged.在波形上点击鼠标并拖动来改变脉冲重复频率，或者在提供的对话框中直接输入新的周期值，而保持脉冲宽度不变。4.Electronicsisthescienceandthetechnologyofthepassageofchargedparticlesinagas,inavacuum,orinasemiconductor.Pleasenotethatparticlemotionconfinedwithinametalonlyisnotconsideredelectronics.电子学是一门有关带电粒子在气体、真空或半导体中运动的科学技术。注意，在本书中粒子运动仅限于金属的情况不属于电子学。5.Hardwaretechnologieshaveplayedvitalrolesinourabilitytouseelectronicpropertiestoprocessinformation,butsoftwareanddataprocessingaspectshavenotdevelopedatthesamespeed.硬件技术在我们使用电子特性来处理信息的能力中一直起着重要作用，而软件及数字处理方面却没能与硬件同步发展。6.However,inaproperlydesignedDCamplifiertheeffectoftransistorparametervariation,otherthanIco,maybepracticallyeliminatediftheoperationpointofeachstageisadjustedsothatitremainsinthelinearoperationrangeofthetransistorastemperaturevaries.然而在设计得当的直流放大器中，若调节每一级的工作点使之在温度变化时保持在晶体管线性区，就能在实际上消除Ico以外的晶体管参数变化所造成的影响。((22))FFiilllliinntthheebbllaannkksswwiitthhtthheemmoossttaapppprroopprriiaatteecchhooiiccee..1.Amessagesignalcananyamplitudevaluebetween0andAvolts.科技英语课件ExercisesHMILYYLIMH2A.assumeB.useC.receiveD.accept2.Eachtimeapositiveclockedgeoccurs,theflip-flopchangesstate,leadingtohalfasmanypulsesattheoutputtotheclockinput.A.asB.comparedC.dueD.soas3.Intheprevioussectionwediscussedsine-waveorCWmodulationsystemsinwhichthemodulatingsignal_______ofadigitalpulsetrain.A.madeB.consistedC.containedD.got4.Inthisbookweshallemphasizethelimitationsimposedontheinformationtransmittedbythesystemthroughwhichitwas_______andshallattemptsomecomparisonofdifferentsystems.A.putB.traveledC.passedD.viewed5.Thissignaleitherdoesnotchange,oritchanges______byanamountequivalenttooneormorequantumsteps.A.interruptedlyB.rudelyC.abruptlyD.absolutely6.Weshallonlybe_______withlogicalrepresentations,notabsolutevaluesA.interestedB.caringC.referredD.concerned((33))CChhoooosseetthheepphhrraasseetthhaattiisscclloosseessttiinnmmeeaanniinnggttootthheeuunnddeerrlliinneeddppaarrtt..1.Itisalltooeasywithlinearcircuits,whichappearrelativelysimplewhencomparedwithtoday’scomplexlogicarrangements,toignoredetailedperformanceparameterswhichcandrasticallyreducetheexpectedperformance.A.whichhasbadinfluenceuponthesystemperformanceB.whichisimportanttoensurecircuitlinearityC.whichispossibletoenhancethesystemperformanceD.whichiscrucialformaintainingthedesiredperformance2.Thereforetherewillbeaslighttimedelay,duetothepropagationdelayoftheflip-flopsbetweenthetimeoneflip-flopchangesstateandthetimethenextonechangesstate,i.e.,thechangeofstateripplesthroughthecounter,andthesecountersarethereforecalledripplecounters.A.thestatechangeispropagatedthroughthecounterlikeripplesB.thestatechangescauseripplesinthecounterC.passingthroughthecounter,thestateripplechangesD.thestateofthecounterchangesduetoripples3.Insteadoftriggeringoneachpulse,aphaselocktechniqueexaminestherelativephasebetweeneachoscillatorandmanyofitssyncpulsesandadjustsoscillatorfrequencysothattheaveragephasediscrepancyissmall.A.checkseachoscillatorformanysyncpulsesB.checksthephaserelationshipbetweenindividualoscillatorsandacollectionofsyncpulsesC.looksattherelationsbetweenthephaseandthesyncpulsesD.examineswhetherthephaseisrelativetotheoscillatorandthesyncpulses4.Bykeepingtheoffstateslightlybelowthreshold,thedelaybetweentheappliedelectrical科技英语课件ExercisesHMILYYLIMH3pulseandtheresultingopticaloutputpulseisminimized;thisdelaymustindeednotbemorethanthebitintervalsothattheopticalpulsecanaccuratelyreproducetheinputsignal.A.ensuringthatthesystemisoffthethresholdbyasmallmarginB.maintainingthesystem’sshut-downstatesomewhatbelowaprescribedlevelC.makingsurethesystemisbelowitsthresholdsothatthestateiskeptoffD.keepingthesysteminashut-downstatethatisunderagivenlevelwithatinytolerance5.Iftheoriginalsignaliswellbehaved,thelocaloscillatorwillneedverylittleinformationtobeabletotrack,andthatinformationcanbeobtainedbyaveragingforalongperiodoftime,therebyeliminatingnoisethatcouldbeverylarge.A.theLOwillnotrequireanyinformationinordertokeeptrackingB.theLOwillmakeuseoftrackinginformationthatisscarceinthesystemC.theLOwillrequiresomeinformation,butnotmuch,sothatthesystemcantrackD.theLOwillusenoinformationotherthansomelittleonetomaintaintracking6.Thethirdsectiondescribesquantizationschemesthattakeaccountofthecharacteristicsofspeech.A.takemeasureofthespeechcharacteristicsB.takethespeechcharacteristicsintoconsiderationC.countthespeechcharacteristicsD.makeuseofthespeechcharacteristics7.InaproperlydesignedDCamplifiertheeffectoft