教材5 Microsoft Word 文档.docx
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138
(4)Whichofthefollowingisfalse?
A.Thecircuitsoftherelayinterlockingthatwerediscussedinthetextaresimple
B.Thecircuitsoftherelayinterlockingwillbemorecomplexwhenthesizeoftheplantis
bigger
C.Thecircuitsoftherelayinterlockingwillbemorecomplexastheplantincreasesmore
functions
D.Thecircuitsoftherelayinterlockingthatwerediscussedinthetextarecomplex
(5)Iftheoperatorleavestheswitchleverinthecenterposition,itwillhappenedthat
A.LKRrelaywasenergized
B.LockindicationlightLEcannotbelit
C.CorrespondencelightWEwillbelit
D.allofabove
Lesson7HighwayCrossingWarningSignal(道口预警信号)
Introduction,
Safetyathighwaygradecrossingshasbeenaconcernofrailroads,rail-transitpropertiesand
governmentatlocal,stateandfederallevels,lAtissueareimpatientmotoristswhocircumventdown
crossinggatesinanattempttodriveoverthecrossingbeforethearrivalofatrain.Thisfrequently
meetswithfatalresultstomotoristsandtraincrews.Theseconcernsareespeciallyacuteinhigh-speed
railterritory,wheregradeseparationofhighwaysandrailwaysisnotpossibleandwherethespeedof
thetrainmakesitnearlyimpossibleforthetrainoperatortostopthetrainoncethecrossingcomes
intoviewandamotorvehiclestalledonthecrossingbecomesvisible?
Typicalarrangements
Flashinglightsignalsareavailableinvariousarrangements,usuallywith4-inchdiameter
aluminummasts,13feethigh.Thesignalmastisusuallyfifteenfeetfromthenearestrail,andsixfeet
fromtheedgeofthehighway.Lampscommonlyusedrangefrom17to25watts.Specialwindowsin
eachlightunitallowpersonnelpassingtrainstocheckwhetherthelampsarelighting.Bellsmaybe
added,aswellassignsindicatingthenumberoftrackstobecrossed.
Atcrossingswheretrainsandtrafficdensityishigher,theinstallationofautomaticgatesin
combinationwithflashinglightsisadvisable?
Thus,theyarethemostefficientcrossingprotection
system.
Housings,asarule,arelocatedabout25feetfromthehighwayand15to20feetfromthe
nearestrailorwhereroomisavailable.Undergroundcablesfeedthesignalsandtrackcircuits,anda
3-inchpipeistypicallyrununderthestreettoprotectthem.Inaddition,warningsignsarealso
installed.
Allinstallationshouldbeinaccordancewithpertinentrailroadandgovernmentrequirement.
139
controlcircuits
Controlcircuitscrossingwarningsystemsaregenerally,similarbutvarywidelyindetailfor
individuallocationbecauseofswitching,stationstops,multipletracks,availabilityofcommercial
power,andotherfactors.Thebasiccontrolcircuitforcrossingwarningsystemsinclude:
trackcircuits
whichcanbesubdividedintoflashinglightcontrolcircuitsandcrossinggatecontrolcircuitetc.
Ontrackswheretrainsareoperatedinbothdirections,thetrackcircuitcontrolsystemmustbe
firrangedtoclearthecrossingsignalsassoonasthetrainsisoffthehighwayintersection--regardless
ofthedirectionofthetrainoperation.4
Lamplightingcircuitforflashinglightsignalcanbedesignedtooperatewhenthetrainoccupies
theapproachingtrack.Whilethetrainhasclearedthehighway,thecontrolcircuitsclearthewarning
devicestopermithighwaytraffictocrossthetrack.
Crossinggatecontrolcircuitsaresimilartoflashinglights.Theprincipledifferenceisinthegate
motorcontrol.Beforethegatesstarttodescend,thelightsandbellsshouldoperatethreetofive
seconds.Thetotaldescenttimeincludingthepreliminarytimelagisaboutfifteenseconds,which
meansthatthegatemaybedownonlyaboutfivesecondsbeforethetrainarrives.Thegateactsasa
physicalbarrier,whilethelightsandbellsgiveadvancewarning.
NewWordsandExpressions
Highwaycrossingwarning道口预警
flashinglightsignal闪光信号机
Available备有的;通用的
Diameter直径
Aluminumn.铝
Mastn.桅杆;支座
Wattn.瓦特
Personnel(全体)人员;职员
Bell电铃
Signn.标志
Automaticgate自动栏木
Advisableadj.可行的;合理的
Undergroundcable地下电缆
Warningsign预告标
Pertinentadj.相应的:
有关的
individual各个的;特殊的
Switchn.道岔
Stationstop车站定点停车
Availabilityn.可用性;现有
Bothdirections双向
Clearacrossingsignal开放道口信号
140
Intersectionn.交叉点
lamplightingcircuit电灯电路
warningdevice预警设备
crossinggate道口栏木,
descend落下
Preliminary预备的,初步的
lag(1田g)以滞后;迟延
Barriern.栅栏
Aswellas以及;像·..。
..一样
Becombinationwith配合;和……共同结合
Regardlessof不管;与·....·无关
NotestotheText
1.Safetyathighwaygradecrossingshasbeenaconcernofrailroads,mil-transitpropertiesand
Governmentatlocal,stateandfederallevels.
译文:
平交道口的安全问题已经成为铁路、铁路运输财产部门以及地方政府,甚至州政府、
联邦政府所关注的问题。
2.Theseconcernsareespeciallyacuteinhigh-speedrailterritory,wheregradeseparationOf
Highwaysandrailwayisnotpossibleandwherethespeedofthetrainmakesitnearlyimpossible
forthetrainoperatortostopthetrainoncethecrossingcomesintoviewandamotorvehicle
Stalledonthecrossingbecomesvisible。
译文:
在那些公路、铁路不可能分离的高速铁路区段,以及一旦司机看到道口及停在道口的
机动车辆时,列车速度使其几乎不可能停下的高速铁路区段,这些问题就尤其严重。
两个“where"引导的是并列的状语从句,“becomes”的主语省略了,仍然是"Theseconcerns”。
3.Atcrossingswheretrainsandtrafficdensityishigher,theinstallationofautomaticgatesin
Combinationwithflashinglightsisadvisable.
译文:
在列车运行密度以及公路交通密度比较大的地方,建议安装自动栏木,并同时安装闪
光信号机。
句子真正的主语是“theinstallationofautomaticgatesincombinationwithflashinglights”,为
被动语态。
4.Ontrackswheretrainsareoperatedinbothdirections,thetrackcircuitcontrolsystemmustbe
arrangedtoclearthecrossingsignalsassoonasthetrainsisoffthehighwayintersection--
RegardlessofthedirectionOfthetrainoperation.
译文:
在列车双向运行的区段,无论列车的运行方向如何,轨道电路控制系统必须设计成列
车一离开道口时就开放道口信号机。
Assoonas一.........就。
“off'’表示“远的”,从上下文推断应该是快要接近但还没到达的地方。
141
ExercisestotheText
ITranslatethefollowingtermsintoChinese.
(1)meetswith
(2)flashinglightsignals(3)crossingprotectionsystem
(4)inaccordancewith(5)flashinglightcontrolcircuits(6)crossinggate
IIDecidewhethereachofthefollowingstatementsistrueorfalseaccordingtothetext.
(1)Theword"this"inline4ofthefirstparagraphreferstosafety.()
(2)Thesignalmastisusually15feetfromthenearestrail,and6feetfromtheedgeofthe
highway.()
(3)Allinstallationofthehighwaycrossingwarningshouldonlybeinaccordancewithpertinent
railroadrules.()
(4)Whenthetrainoccupiestheapproachingtrack,lamplightingcircuitforflashinglightsignal
canoperate.()
(5)Fromthetextweknowthattheflashinglightsignalgivesadvancewarning.()
IIIAnswerthefollowingquestionsaccordingtothetext.
(1)Whereareflashinglightsignalsinstalled?
(2)Whencanlamplightingcircuitforflashinglightsignaloperate?
(3)Whenarethewarningdevicesclearedtopermithighwaytraffictocrossthetrack?
(4)What'sthedifferencebetweencrossinggatecontrolcircuitsandflashinglightscircuits?
Readingmaterial
Four-QuadrantGateHighway-CrossingWarningSystem
Toattempttoimprovegrade-crossingsafetyforbothmotorvehiclesandtrains,particularlyat
high-speedlocations,US&ShasdevelopedtheFour-QuadrantGateHighway-CrossingWarning
System.
Thesystemprimarilyconsistsoffourhighway-crossingsignal/gateassemblies,aninductive
motor-vehicledetectionloop,avitalprocessor,acabsignalsysteminterfaceinrailterritoryequipped
withcabsignaling,andapproachandislandtrackcircuits.Gateoperationiscontrolledsothatmotor
vehicleswillnotbetrappedonthecrossingduringtheapproachofatrain.
Signal/Gateassemblies
TwoModel95signal/gateassembliesareinstalledoneachsideofthetracksothehighwayis
completelyblockedonbothsidesoftherailright-of-waywhenthegatesaredownandatrainis
approachingthecrossing.
Loopdetectors
Loopdetectorsareburiedbeneaththecrossingsurfacefordetectingmotorvehicles.Sincethe
loopdetectors'inductancevarieswheneveramotorvehiclepassesoverthecrossing,thepresenceofa
motorvehicleonthecrossingwillbedetected.Theloopoutputissenttothewarningsystem's
vital/non-vitalprocessor.Ifavehicleisonthecrossingwhenatrainapproachesandactivatesfromthe
highway-crossingwarningsystem,theexitgateswillremainraisedtoallowthevehicletoexitfromthe
142
crossing.Onceagain,thisfeatureprovidesanexitforthevehiclesoit'snottrappedonthecrossingby
allfourgatesbeingdown.
Vital/non-vitalprocessor
Thewaysidecontrolsystemfunctionsasavital/non-vitalprocessor,andservesastheheartof
thecontrolsystem.Itexecutesthevitallogicrequiredforgateoperation,motor-vehicledetection,and
thelocomotivecabindicationsThisprocessoralsotestsforloop-detectorfaults,crossing-system
Intrusionandbrokengates,and,ifanyoftheseconditionsaredetected,itgeneratesamaintenance
call.
Trackcircuits
Trackcircuitsdetectthepresenceofatrainwithinthecrossingapproachesandontheisland
(wheretrackandroadmeet)andinitiateoperationofthehighwaycrossingwarningsystem.
Operation
Withnotrainapproachingthecrossing,thegatesarevertical,theflashingwarninglightsonthe
signalgateassembliesaredark,thewarningbellissilentandtrack-circuitrelaysareenergized.The
vitalportionofthesystemconstantlymonitorsthestatusoftheloopdetectorsthatindicatewhethera
motorvehicleistravelingoverorisstoppedonthecrossing.Loopstatusinformationalsoispassedto
thenon-vitalportionoftheprocessor,whichdirectstheinformationtoadataloggerforrec
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