资源描述：
《2013高考英语二轮复习 专题限时训练(三十七) 科普知识型阅读理解配套作业(一)（解析版，新课标）》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、专题限时训练(三十七) [科普知识型阅读理解(一)](限时：25分钟) (一)Trafficlightsarekeytoolsforregulatingtrafficnow.Theyarenot,however,perfect.Driversexchangethetrafficjamsthatwouldhappenatunmanagedcrossingsforapatternofstopgomovementthatcanstillbeannoying,andwhichburnsmorefuel
2、thanasmoothpassagewould.Creatingsuchasmoothpassagemeansadjustingavehicle'sspeedsothatitalwaysarrivesatthelightswhentheyaregreen.Thatistheoreticallypossible,butpracticallyhard.Roadsidesignswiredtotrafficlightscanhelpgetthemessageacrossacouplehundredmetresfromacrossin
3、g,butsuchsignsareexpensive,andarenotwidespread.MargaretMartonosiandEmmanouilKoukoumidisatPrincetonUniversity,andLiShiuanPehattheMassachusettsInstituteofTechnology,however,haveanideathatcouldmaketheprocesscheaperandmoreeffective.Insteadofahardwirednetworkofsigns,they
4、proposetousemobilephoneapplications.Foradrivertobenefit,hemustloadtheteam'ssoftware,namedSignalGuru,intohisphoneandthenputitonaspecialthingattachedtotheinsideofhiscar'swindscreen,withthecameralens(镜头)pointingforward.SignalGuruisdesignedtodetecttrafficlightsandtrackt
5、heirstatusasred,yelloworgreen.Itbroadcaststhisinformationtootherphonesintheareathatarefittedwiththesamesoftware,and—ifthereareenoughofthem,thephonesthuseachknowthestatusofmostofthelightsaroundtown.Usingthisinformation,SignalGuruisabletocalculatethetrafficlightschedu
6、lefortheareaandsuggestthespeedatwhichadrivershouldtravelinordertoavoidredlights.TestsinCambridge,Massachusetts,wherefivedriverswereaskedtofollowthesamerouteforthreehours,andinSingapore,whereeightdriverswereaskedtofollowoneoftworoutesfor30minutes,revealedthatSignalGu
7、ruwascapableofpredictingtrafficlightactivitywithanaccuracyof98.2%and96.3%respectively,inthetwocities.ThiswasparticularlyimpressivebecauseinCambridgethelightsshifted,roughlyhalfwaythroughthetest,fromtheirunbusyscheduletotheirafternoontrafficschedule,whileinSingaporel
8、ightsareadaptive,usingdetectorsfixedundertheroadtodeterminehowmuchtrafficispresentandthuswhenasignalshouldchange.InneithercasewasSignalGur
