测绘专业英语部分翻译

测绘工程专业英语论文班级：测绘1401学号：201408246姓名：田强华ReductionofShort-IntervalGPSDataforConstructionOperationsAnalysisJohnHildreth,M.ASCE1;MichaelVorster,M.ASCE2;andJulioMartinez,M.ASCE3Abstract:Thesystemsthathistoricallyhavebeenusedtocollectdatafortimestudiesofconstructionoperationsaremanualinnatureandlimitedtotheobserver'sfieldofview.GlobalPositioningSystem(GPS)technologyincorporatedintoanonboardinstrumentationsystemcanbeusedtoautonomouslycollectpositionandvelocitydatawithoutthefieldofviewlimitation.Datamustbecollectedatashorttimeintervaltoprovidethelevelofdetailnecessaryforoperationsanalysis.Thustheissuebecomesmanagingthedataandidentifyingtherelativelykeyrecordsthatmarkthestartandstopofactivities.Afieldobserveridentifiesthekeytimesinrealtimewithinstantaneousdecisionsofwhenoneactivitystopsandthenextstartsbasedonenormousvolumesofvisualinformation.ThisworkdevelopedamethodologyformakingequivalentdecisionsbasedonGPSdataandpresentstheproceduresdevelopedtoidentifythekeyrecordsnecessarytocalculateactivitydurations.Acasestudyisusedtoillustrateapplicationofthesystemtoanearthmovingoperation.Also,itispostulatedhowtheinformationcanbeusedindiscreteeventsimulation.DOI:10.1061/(ASCE)0733-9364(2005)131:8(920)CEDatabasesubjectheadings:Geographicinformationsystems;Constructionindustry;Dataanalysis;Informationmanagement;Timestudies.IntroductionTimestudieshistoricallyhavebeenperformedtorecordthetimerequiredtocompletevariousconstructiontasks(Oglesbyetal.1989).Theoriginaltimestudysystemwasthestopwatch,whichhassincebeenreplacedbytime-lapsevideorecordings.Thesesystemsaremanualinnatureandlimitedtothefieldofviewoftheobserver,orwhatiswithinthelineofsightoftheobserver.Recently,analystshaveturnedtotechnologyfornewtools.Whetheranobserverperformsthestudyinthefieldwithastopwatchortheoperationisfilmedforpreliminaryreviewanddatareductionintheoffice,theinformationislimitedtothefieldofviewoftheobserverorcamera.Analystshavelookedtoon-boardinstrumentationasadatacollectiontoolusefulbeyondthefieldofview.GlobalPositioningSystem(GPS)technologyincorporatedintoanonboardinstrumentationsystemcanprovidepositionandvelocitydataasapotentialsolutiontothefield-of-viewissue.However,recordingdatafrequentlyenoughtoprovidegoodre-sultsproducesaverylargevolumeofdata.Withseveralthousanddatarecordsproduceddailyoneachpieceofinstrumentedequip-ment,theissuebecomesmanagingthedataandidentifyingtherelativelyfewkeyrecordsthatmarkthebeginningandendoftheactivitiesbeingstudied.Regardlessofthetoolimplemented,theprocessisperformedinfourphases:datacapture,preliminaryreview,datareduction,anddataanalysis.ThetoolsusedineachphaseforvarioussystemscanbeseeninTable1.Afieldobserveridentifiesthekeytimesinrealtimewithin-stantaneousdecisionsofwhenoneactivitystopsandthenextstartsbasedonenormousvolumesofvisualinformation.Thiswork狼斓2016/10/1713:41:28developedamethodologyformakingequivalentdecisionsbasedonGPSdata,specificallytoanswerthequestion,Howcanthelargevolumeofshort-intervalGPSdatacollectedbeauto-maticallyreducedtothesmallvolumeofkeydiscretepointsthatmarkthestartandstopofactivities?ThispaperbrieflydescribesthehardwareusedtorecordthenecessaryGPSdataandpresentsproceduresdevelopedtoidentifythekeyrecordsnecessarytocalculateactivitydurations.Acasestudyisusedtoshowtheapplicationofthesystemtoanearth-movingoperation.Thispaperalsopostulateshowtheinformationfromthedatacanbeusedindiscreteeventsimulations.Descrip-tionsofdiscreteeventsimulationappliedtoconstructionopera-tionscanbefoundinMartinezandIoannou(1995),IoannouandMartinez(1996a),Martinez(1998),Sangarayakul(1998),CorandMartinez(1999),andIoannou(1999).PreviousWorkAnearlyuseofGPStocollectproductivitydatawasapilotstudydesignedtoprovidecurrentinformationregardingearthworkoperations(Ackroyd1998).PositioninformationwastransmittedviaradioandrecordedbyaremotePCat2-minintervalsandattheclosureofproximityswitchesonleversofarticulatedhaulersandmotorscrapers.Intheinitialphase,analysisofthedatafocusedonmeasuringcycletimes,butnorealanalysiswasperformedofpositionsbetweenevents.Inasecondphase,straingaugeswereusedtoestimatepayloadandtherebyprovideproductivitydata.ThisworkdepictsthepotentialofGPSforrecordingdatafromearthmovingoperationsbutfocusesonthehardwareissuesratherthanthedatareductionissues.Ackroydconcludesthattheinformationmayaddvaluetomonitoringandschedulingtasksbutdoesnotaddressuseofthedataforanalyzingearthmovingoperations.FieldDataReductionOglesbyetal.(1989)pointoutthatthepurposeofatimestudyistorecordthetimesofvariousactivitiesthatmakeupanoperation.Thesimplesttimestudies—stopwatchstudies—relyontheobservertodecidethepointintimeatwhichactivitiesstartandstop.Oglesbyetal.(1989)notethatplacingthisresponsibilityontheobserverlimitstheusefulnessofthedata.Observerscanhavedifferencesinopinion,datarecordedbyasingleobservermayvaryovertime,availableinformationisstrictlylimitedtothatrecordedandissubjecttothephysicallimitationsoftheobserver.Additionally,theinformationrecordedisstrictlylimitedtothefieldofviewoftheobserver.BjornssonandSagert(1994)presentedPAVIC+asacomputer-b