职称英语考试真题及答案理工类B级.docx
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职称英语考试真题及答案理工类B级
2020年职称英语考试真题及答案(理工类B级)
CanyouhearThis?
Whensomethingcreatesasoundwaveinaroomoranauditorium(礼堂),listenershearthesoundwavedirectlyfromthesource.Theyalsohearthereflectionsasthesoundbouncesoffthewalls,floor,andceiling.Thesearecalledthereflectedwaveorreverberant(反射的)sound,whichcanbeheardevenafterthesoundisnolongercomingfromthesource.
Thereverberationtimeofanauditoriumisdeterminedbythevolumeorinteriorsizeoftheauditorium.Itisalsodeterminedbyhowwellorhowpoorlythewalls,ceiling,floor,andcontentsoftheroom(includingthepeople)absorbsound.Thereisnoidealreverberationtime.Thefull-soundperformanceofmusicsuchasWagneroperasorMahlersymphoniesshouldhavealongreverberationtime.Thelight,rapidmusicalpassagesofBachorMozartneedareverberationtimesomewherebetween.
Acousticproblemsoftenarecausedbypoorauditoriumdesign.Smooth,curved(弯曲的)reflectingsurfacescreatelargereflections.Parallel(平行的)wallsreflectsoundbackandforth,creatingarapid,repetitivepulsing(有节奏的跳动)effect.Largepillars(柱)andcornerscancauseacousticshadowsasthesoundwavestrytopassaroundtheobject.Someoftheseproblemscanbesolvedbyusingabsorbersandrelectorstochangethereverberationtimeofaroom.Forexample,hanginglargereflectors,calledclouds,overtheperformerswillallowsomesoundfrequenciestoreflectandotherstopassyoachieveapleasingmixtureofsound.
1.ThisPassageismainlyabout
Asoundwavesandtheiracousticeffect.
Bthetypesofmusicorchestrasplay
Cwallsofanauditorium
Dthedesignofanauditorium
2.WagneroperasandMahlersymphoniessoundfullerinanauditoriumwith
~2/3~
Aashortreverberationtime
Balongreverberationtime
Canintermediatereverberationtime
Dnoreverberationtime
3.Thispassagesuggeststhatagoodauditoriumshould
Aachieveapleasingmixtureofsound
Bgetridofallreflections
Cnothaveabsorbers.
Dhavesmoothsurfaces
4.Largepillarsandcornersmay
Amakesoundrichandfull
Bbecuresforsoundproblems
Cbesourcesofsoundproblems
Dfunctionaswellasclouds
5.Theword“acoustic“inthelastparagraphhassomethingtodowith
AperformanceBMusic
CsoundDnoise
SmartWindow
Windowsnotonlyletlightintocutdownanelectricityuseforlighting,butthelightcomingthroughthewindowalsoprovidesheat.However,windowsarenotsomethingpeopletypicallyassociatewithbeingacuttingedge1technology.Researchersarenowworkingonnewtechnologiesthatenableawindowtoquicklychangefromcleartodarkandanywhereinbetweenwithaflipofaswitch2.
“Ittookusalongtimetofigureoutwhatawindowreallyis,”saysClaesGranqvist.He’saprofessorofsolid-statephysicsatUppsalaUniversityinSweden3.“It’scontactwiththeoutsideworld.Youhavetohavevisualcontactwiththesurroundingworldtofeelwell.”So,windowsandnaturallightareimportantforimprovingthewaypeoplefeelwhenthey’restuckindoors.
Yet,windowsaretheweaklinkinabuildingwhenitcomestoenergyandtemperaturecontrol.Inthewinter,coldairleaksin.Whenit’shotandsunny,sunlightstreamsin.Allofthissunlightcarrieslotsofheatandenergy.Andallofthisextraheatforcespeopletoturnontheirairconditioners.Producingblastsofcoldair,whichcanfeelsorefreshing,actuallysuckupenormousamountsofelectricityinbuildingsaroundtheworld.
Windowshavebeenamajorfocusofenergyresearchforalongtime.Overtheyears,scientistshavecomeupwithavarietyofstrategiesforcoating,glazing,andlayeringwindowstomakethemmoreenergyefficient.Smartwindowsgoastepfurther.Theyusechromogenictechnologieswhichinvolvechangesofcolor.
Electrochromicwindowsuseelectricitytochangecolor.Forexample,asheetofglasscoatedwiththinlayersofchemicalcompoundsuchastungstenoxideworksabitlikeabattery.Tungstenoxideisclearwhenanelectricchargeisappliedanddarkwhenthechargeisremoved,thatis,whentheamountofvoltageisdecreased,thewindowdarkensuntilit’scompletelydarkafterallelectricityistakenaway.Soapplyingavoltagedetermineswhetherthewindowlooksclearordark.
Oneimportantfeaturethatmakesasmartwindowsosmartisthatithasasortof“memory.”Allittakesisasmalljoltofvoltagetoturnthewindowfromonestatetotheother.Then,itstaysthatway.Transitionstakeanywherefrom10secondstoafewminutes,dependingonthesizeofthewindow.Thedevelopmentofsmartwindowscouldmeanthatmassiveairconditioningsystemsmaynolongerneed.“Inthefuture,”Granqvist