直接启动电动机的缺点是_______。

A、所需设备复杂
B、启动时间长。
C、对电动机及电网有一定的冲击。
D、电动机的启动转矩减少。
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正确答案:

C

答案解析:

暂无解析

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Iftheoldmaximthatthecustomerisalwaysrightstillhasmeaning,thentheairlinesthatplytheworld’sbusiestairroutebetweenLondonandParishaveaflightontheirhands.

TheEurostartrainservicelinkingtheUKandFrenchcapitalsviatheChannelTunneliswinningcustomersinincreasingnumbers.InlateMay,itcarrieditsonemillionthpassenger,havingrunonlyalimitedservicebetweenLondon,ParisandBrusselssinceNovember1994,startingwithtwotrainsadayineachdirectiontoParisandBrussels.By1997,thecompanybelievesthatitwillbecarryingtenmillionpassengersayear,andcontinuetogrowfromthere.

FromJuly,EurostarstepsitsservicetoninetrainseachwaybetweenLondonandParis,andfivebetweenLondonandBrussels.Eachtraincarriesalmost800passengers,210oftheminfirstclass.

Theairlinesestimatethattheywillinitiallylosearound15%-20%oftheirLondon-ParistraffictotherailwaysonceEurostarstartsafullservicelaterthisyear(1995),with15trainsadayeachway.AsimilarservicewillstarttoBrussels.Thedamagewillbelimited,however,theairlinesbelieve,withpassengernumbersreturningtopreviouslevelswithintwotothreeyears.

Intheshortterm,thedamagecausedbythe1millionpeople-levelstravelingbetweenLondonandParisandBrusselsonEurostartrainsmeansthatsomeairservicesarealreadysuffering.Someofthemajorcarrierssaythattheirpassengernumbersaredownbylessthan5%andpointtotheirrivals-ParticularlyAirFrance-ashavingsufferedtheproblems.OntheBrusselsroute,therailwaycompanyhadlesssuccess,andtheairlinesreportanythingfromarounda5%droptonovisibledeclineintraffic.

Theairlines’optimismonreturningtrafficlevelsisbasedonhistoricalprecedent.BritishMidland,forexample,pointstoitsexperienceonHeathrowLeedsBradfordservicewhichsawpassengernumbersfoldby15%whenBritishRailelectrifiedandmodernizedtherailwaylinebetweenLondonandYorkshire.Twoyearslater,travelhadrisenbetweenthetwodestinationstothepointwheretheairlinewascarryingrecordnumbersofpassengers.

1.Britishairlinesconfideinthefactthat__.

A.theyaremorepowerfulthanotherEuropeanairlines.

B.theirtotallosswon’tgobeyondadropof5%passengers.

C.theirtrafficlevelswillreturnin2-3years.

D.travelingbyrailcannevercatchupwithtravelingbyair.

2.Theauthor’sattitudetowardsthedropofpassengersmaybedescribedas__.

A.worried.B.delightedC.puzzled.D.unrivaled.

3.Inthepassage,BritishRail(Para6)ismentionedto__.

A.provideacomparisonwithEurostar.

B.supporttheairlines’optimism.

C.provetheinevitabledropofairpassengers.

D.callforelectrificationandmodernizationoftherailway.

4.Therailway’sBrusselsrouteisbroughtforthtoshowthat__.

A.theEurostartrainserviceisnotdoinggoodbusiness.

B.theairlinescanwellcompetewiththerailway.

C.theEurostartrainserviceonlycausedlittledamage.

D.onlysomeairlines,suchasAirFrance,aresuffering.

5.Thepassageistakenfromthefirstofanessay,fromwhichwemaywellpredictthatinthefollowingparttheauthorisgoingto__.

A.praisetheairlines’clear-mindedness.

B.warntheairlinesofhigh-speedrailservices.

C.proposeareductionofLondon/Parisflights.

D.advisetheairlinestofollowBritishMidlandastheirmodel.

Mostofusaretaughttopayattentiontowhatissaid—thewords.Wordsdoprovideuswithsomeinformation,butmeaningsarederivedfromsomanyothersourcesthatitwouldhinderoureffectivenessasapartnertoarelationshiptorelytooheavilyonwordsalone.Wordsareusedtodescribeonlyasmallpartofthemanyideasweassociatewithanygivenmessage.Sometimeswecangaininsightintosomeofthoseassociationsifwelistenformorethanwords.Wedon’talwayssaywhatwemeanormeanwhatwesay.Sometimesourwordsdon’tmeananythingexcept“I’mlettingoffsomesteam.Idon’treallywantyoutopaycloseattentiontowhatI’msaying.JustpayattentiontowhatI’mfeeling.”Mostlywemeanseveralthingsatonce.Apersonwantingtopurchaseahousesaystothecurrentowner,“ThisstephastobefixedbeforeI’llbuy.”Theownersays,“It’sbeenlikethatforyears.”Actually,thestephasn’tbeenlikethatforyears,buttheunspokenmessageis:“Idon’twanttofixit.Weputupwithit.Whycan’tyou?”Thesearchforamoreexpansiveviewofmeaningcanbedevelopedofexaminingamessageintermsofwhosaidit,whenitoccurred,therelatedconditionsorsituation,andhowitwassaid.

Whenamessageoccurscanalsorevealassociatedmeaning.Letusassumetwocouplesdoexactlythesameamountofkissingandarguing.Butonecouplealwayskissesafteranargumentandtheothercouplealwaysarguesafterakiss.Theorderingofthebehaviorsmaymeanagreatdealmorethanthefrequencyofthebehavior.Afriend’sunusuallydocilebehaviormayonlybeunderstoodbynotingthatitwasprecededbysituationsthatrequiredanabnormalamountofassertiveness.Someresponsesmaybedirectlylinkedtoadevelopingpatternofresponsesanddefylogic.Forexample,apersonwhosays“No!”toaserialsofchargeslike“You’redumb,”“You’relazy,”and“You’redishonest,”mayalsosay“No!”andtrytojustifyhisorherresponseifthenextstatementis“Andyou’regoodlooking.”

Wewoulddowelltolistenforhowmessagesarepresented.Thewords,“Ifsurehasbeennicetohaveyouover,”canbesaidwithemphasisandexcitementorritualistically.Thephrasecanbesaidonceorrepeatedseveraltimes.Andthemeaningsweassociatewiththephrasewillchangeaccordingly.Sometimesifwesaysomethinginfrequentlyitassumesmoreimportance;sometimesthemorewesaysomethingthelessimportanceitassumes.

1.Effectivecommunicationisrenderedpossiblebetweentwoconversingpartners,if___.

A.theyuseproperwordstocarrytheirideas.

B.theybothspeaktrulyoftheirownfeelings.

C.theytrytounderstandeachother’sideasbeyondwords.

D.theyarecapableofassociatingmeaningwiththeirwords.

2.“I’mlettingoffsomesteam”inparagraph1means___.

A.I’mjustcallingyourattention.

B.I’mjustkidding.

C.I’mjustsayingtheopposite.

D.I’mjustgivingoffsomesound.

3.Thehouse-owner’sexampleshowsthatheactuallymeans___.

A.thestephasbeenlikethatforyears.

B.hedoesn’tthinkitnecessarytofixthestep.

C.theconditionofthestepisonlyaminorfault.

D.thecostinvolvedinthefixingshouldbeshared.

4.Someresponsesandbehaviorsmayappearveryillogical,butarejustifiableif___.

A.linkedtoanabnormalamountofassertiveness.

B.seenasone’shabitualpatternofbehavior.

C.takenaspartofanorderingsequence.

D.expressedtoaseriesofcharges.

5.Theword“ritualistically”inthelastparagraphequalssomethingdone___.

A.withouttrueintention.

B.light-heartedly.

C.inawayofceremony.

D.withlessemphasis.

Whiledoingcalculationfortheproject,thedesigners____anewsolutiontoageologicalproblem.

A、fellinto
B、stumbledupon
C、setout
D、discovered

患者男,40岁,2周来右侧咬物不适,冷水引起疼痛,近2日来夜间疼痛,影响睡眠,并引起半侧头痛,疼痛不能定位,检查右侧上、下磨牙面均有深的龋洞。对患牙的应急处理为

A、拔除
B、开髓引流
C、抗炎止痛
D、安抚治疗
E、间接盖髓充填

_____,hewouldnothaverecoveredsoquickly.

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B、Hadhenotbeentakengoodcareof
C、Hadnothebeentakengoodcareof
D、Hadhebeennottakengoodcareof
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