科技英语课件Unit120+Exercises.docx
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科技英语课件Unit120+Exercises
Unit1Exercises
(1)TranslatethefollowingsentencesintoChinese.
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。
(2)Fillintheblankswiththemostappropriatechoice.
1.Amessagesignalcananyamplitudevaluebetween0andAvolts.
A.assumeB.useC.receiveD.accept
2.Eachtimeapositiveclockedgeoccurs,theflip-flopchangesstate,leadingtohalfasmanypulsesattheoutputtotheclockinput.
A.asB.comparedC.dueD.soas
3.Intheprevioussectionwediscussedsine-waveorCWmodulationsystemsinwhichthemodulatingsignal_______ofadigitalpulsetrain.
A.madeB.consistedC.containedD.got
4.Inthisbookweshallemphasizethelimitationsimposedontheinformationtransmittedbythesystemthroughwhichitwas_______andshallattemptsomecomparisonofdifferentsystems.
A.putB.traveledC.passedD.viewed
5.Thissignaleitherdoesnotchange,oritchanges______byanamountequivalenttooneormorequantumsteps.
A.interruptedlyB.rudelyC.abruptlyD.absolutely
6.Weshallonlybe_______withlogicalrepresentations,notabsolutevalues
A.interestedB.caringC.referredD.concerned
(3)Choosethephrasethatisclosestinmeaningtotheunderlinedpart.
1.Itisalltooeasywithlinearcircuits,whichappearrelativelysimplewhencomparedwithtoday’scomplexlogicarrangements,toignoredetailedperformanceparameterswhichcandrasticallyreducetheexpectedperformance.
A.whichhasbadinfluenceuponthesystemperformance
B.whichisimportanttoensurecircuitlinearity
C.whichispossibletoenhancethesystemperformance
D.whichiscrucialformaintainingthedesiredperformance
2.Thereforetherewillbeaslighttimedelay,duetothepropagationdelayoftheflip-flopsbetweenthetimeoneflip-flopchangesstateandthetimethenextonechangesstate,i.e.,thechangeofstateripplesthroughthecounter,andthesecountersarethereforecalledripplecounters.
A.thestatechangeispropagatedthroughthecounterlikeripples
B.thestatechangescauseripplesinthecounter
C.passingthroughthecounter,thestateripplechanges
D.thestateofthecounterchangesduetoripples
3.Insteadoftriggeringoneachpulse,aphaselocktechniqueexaminestherelativephasebetweeneachoscillatorandmanyofitssyncpulsesandadjustsoscillatorfrequencysothattheaveragephasediscrepancyissmall.
A.checkseachoscillatorformanysyncpulses
B.checksthephaserelationshipbetweenindividualoscillatorsandacollectionofsyncpulses
C.looksattherelationsbetweenthephaseandthesyncpulses
D.examineswhetherthephaseisrelativetotheoscillatorandthesyncpulses
4.Bykeepingtheoffstateslightlybelowthreshold,thedelaybetweentheappliedelectricalpulseandtheresultingopticaloutputpulseisminimized;thisdelaymustindeednotbemorethanthebitintervalsothattheopticalpulsecanaccuratelyreproducetheinputsignal.
A.ensuringthatthesystemisoffthethresholdbyasmallmargin
B.maintainingthesystem’sshut-downstatesomewhatbelowaprescribedlevel
C.makingsurethesystemisbelowitsthresholdsothatthestateiskeptoff
D.keepingthesysteminashut-downstatethatisunderagivenlevelwithatinytolerance
5.Iftheoriginalsignaliswellbehaved,thelocaloscillatorwillneedverylittleinformationtobeabletotrack,andthatinformationcanbeobtainedbyaveragingforalongperiodoftime,therebyeliminatingnoisethatcouldbeverylarge.
A.theLOwillnotrequireanyinformationinordertokeeptracking
B.theLOwillmakeuseoftrackinginformationthatisscarceinthesystem
C.theLOwillrequiresomeinformation,butnotmuch,sothatthesystemcantrack
D.theLOwillusenoinformationotherthansomelittleonetomaintaintracking
6.Thethirdsectiondescribesquantizationschemesthattakeaccountofthecharacteristicsofspeech.
A.takemeasureofthespeechcharacteristics
B.takethespeechcharacteristicsintoconsideration
C.countthespeechcharacteristics
D.makeuseofthespeechcharacteristics
7.InaproperlydesignedDCamplifiertheeffectoftransistorparametervariationmaybepracticallyeliminatediftheoperatingpointofeachstageisadjustedsothatitremainsinthelinearoperationrangeofthetransistorastemperaturevaries.
A.theeffectivevariationofthetransistorparameters
B.theefforttochangetransistorparameters
C.thetransistorparametersthateffectivelychange
D.theresultscausedbytransistorparameterchanges
8.Stabilityandrepeatabilityarefundamentalattributesofdigitalcircuits,however,andthenecessaryaccuracycanbeobtainedinadigitalversionofthemodulatorbyanappropriatechoiceofwordlengthtorepresentthesignals.
A.byexpressingthesignalswithasuitablewordlength
B.byusingawordlongenoughtodescribethesignals
C.bychoosetocharacterizethesignalsintermsofwordlengthappropriately
D.byappropriatelyrepresentingthesignalstochoosealengthofwords
Unit2Exercises
(1)TranslatethefollowingsentencesintoChinese.
1.Ifanalogsignalsaretobetransmitteddigitally,theyfirsthavetobesampledataspecifiedrateandfurtherconvertedtodiscreteamplitudesamplesbyquantization.
如果要以数字方式传输模拟信号,首先必须以一定的频率对信号进行采样,然后通过量化进一步将它们转换为离散的幅度样本。
2.Linearfiltersamplifyorattenuateselectedspatialfrequencies,canachievesucheffectsassmoothingandsharpening,andusuallyformthebasisofre-samplingandboundarydetectionalgorithms.
线性滤波器放大或衰减选择的空间频率,能够实现像平滑和锐化这些效果,通常是重采样和边缘检测算法的基础。
3.Stabilityandrepeatabilityarefundamentalattributesofdigitalcircuits,however,andthenecessaryaccuracycanbeobtainedinadigitalversionofthemodulatorbyanappropriatechoiceofwordlengthtorepresentthesignals.
不过稳定性和可重复性是数字电路的基本性质,在数字式调制器中必要的精度可通过适当地选择代表信号的字长而获得。
4.Thefirstobservationismadeonthefundamentalrelationshipbetweenthenatureofsystemandtheperiodicityofitsfrequencyresponse:
acontinuoussystemhasanaperiodicfrequencyresponse,whileadiscretesystemhasaperiodicfrequencyresponse.
从系统性质和它频率响应的周期性之间的基本关系中首先可以看到:
连续系统有非周期性的频率响应,而离散系统有周期性的频率响应。
5.Themainfunctionofthereceiveristoextracttheinputmessagesignalfromthedegradedversionofthetransmittedsignalcomingfromthechannel.
接收器的主要功能是从由信道传输来的退化了的信号中提取出输入消息。
(2)Choosethewordorphrasethatisclosestinmeaningtotheunderlinedpart.
1.Roughlyspeaking,thetransistorcanbelikenedtoanelectronicallycontrolledvalvewherebyenergyappliedtooneconnectionofthevalveenablesenergytoflowbetweentwootherconnections.
A.related
B.linked
C.analogized
D.viewed
2.Whilethirdpartydesigntoolswereavailable,therewasnotaneffectivelinkfromthethirdpartydesigntoolstothelayoutandactualsemiconductorprocessperformancecharacteristicsofthevariousASICmanufacturers.
A.When
B.Although
C.As
D.Since
3.Thesesteps,implementedwithalevelofskillcommonintheindustry,almostalwaysproduceafinaldevicethatcorrectlyimplementstheoriginaldesign,unlessflawsarelaterintroducedbythephysicalfabricationprocess.
A.practicedusingskillsgenerallyavailableintheindustry
B.commonlyperformedatlevelsofskilledpersonnelintheindustry
C.realizedwiththeskillfulcommonlevelintheindustry
D.carriedoutbyskillscommonlyusedintheindustry
4.Asecondmajorstepwouldbetodevelopdesignspecificationsthatconsiderthefunctionalityofthehumanwiththesamedegreeofcarethathasbeengiventotherestofthesystem.
A.developdesignprocedurestoaccountforthehumanbehaviorandactivities
B.promotedesignarrangementsandtakethehumanfactorsintoconsideration
C.makeusedofdesignstepsthatrespectthehumanfunctionality
D.draftandeffectdesignrequirementsthattakeintoaccountthehumanfunctionality
5.Clickmouseonthewaveformanddragittochangethepulserepetitionrateordirectlyenteranewvalueoftheperiodintheprovideddialoguebox,keepingthepulsewidthunchanged.
A.simplytypeanewperiodvalueinthegivendialoguebox
B.directanentryforthenewperiodvaluetothedialoguebox
C.pointastraightforwardnewperiodvaluetothedialoguebo