职称英语考试真题及答案理工类B级Word下载.docx

职称英语考试真题及答案理工类B级Word下载.docx

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　　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