外文翻譯-基于GPS、GPRS、GIS和互聯(lián)網(wǎng)的車輛定位系統(tǒng)

英文文獻(xiàn)原文BasedontheGPS,GPRS,GISandInternetvehiclepositioningsystemAbstractThispaperintroducesanintegratedgeographicinformationsystem(GIS),combinedwiththeapplicationofglobalpositioningsystem(GPS),generalpacketradioservice(GPRS)andInternetvehiclepositioningsystem.Foraneedtostudyandmanagementofvehiclepositioningoftheenterprise,chooseasuitablevehiclepositioningsystemisveryimportant.Themainfeatureofthesystemistheuseofopengeographicinformationsystemplatformtoaccesstoresources,usingtheInternetbaseduserinterface,realizationofvehiclepositioninginformationupdate.ThesystemconsistsofGPSbasedpositioningdeviceofthevehicle,communicationserver,webserver,databaseserveranddesktopmapcomposition.Positioningdeviceinstalledinthevehicleinterior,throughtheGPSpositiontocollectreal-timeinformation,theinformationistransmittedtoacentraldatabasethroughGPRS.TheusercanthroughtheInternetinreal-timeshowthelocationofeachvehicle,andthenforallvehiclesmanagement.Vehiclepositionandotherrelatedinformationwillbedisplayedinthedesktopmapgeneratedbyanelectronicmap.Thissystemistheuseofinformationandcommunicationtechnologycombinedwitheachotherandform.Thesharpriseinfuelprices,thissystemwassuccessfullyusedonacompany'sresourcesforeffectivemanagementofgreathelp.Keywords:theglobalpositioningsystem(GPS),generalpacketradioservice(GPRS),vehiclepositioning,desktopmap,Internet,informationcommunicationtechnology.1、Introduction：Thisvehiclepositioningsystemtheintegrateduseofmoderninformationtechnologyandcommunicationtechnology,appliedtohavemorevehiclesenterprises,enterprisescanusethissystemforvehicletrackingandmanagement.Thissystemconsistsofvehicletrackingdevice,thecentralserversystemandInternet.Throughthissystem,userscanusetheircomputercontroldesktopmap,andthenunderstandthegeographiclocationofthevehicleandotherrelevantinformation.Thispaperfocusesonthedesignanddevelopmentofvehiclepositioningsysteminthe.However,thissystemhasalotofotherunits,includingthemanagementofsystemresources(drivers,vehicles),andefficientuseof(vehicleallocationproblem)andreportgenerationandauditactivitiessuchaspartof.Thesystemisdesignedtoservealargefleetofvehiclesorcomplexrequirementsoftheuseofenterprise.Workersmayneedfrequentuseofshorttrips,aswellassomelong-distancetravel.Somemayvisitashortperiodoftimecanbedetermined,andsometravelmayneedtomatchthecorrespondingdailyschedule.Employeesmaysometimesrequireextendedtripsoraparkinglot,butthevehiclerepairoftenmeettemporaryneeds.Theseissuesrequireamoreeffectivevehiclepositioningsystemtosolve,inordertomeettheaboverequirements,needadiversificationstrategy.Inordertoimprovethecompanyoverallproductivity,mustonallvehiclecentralizedmanagement.Thispaperusesavarietyoftechniquestoachievethisgoal.Thefollowingexampleshows:wecantakeavarietyofscienceandtechnologyarecombinedtosolvearealproblem.2GPSandGPRSdefinition2.1GPSGPSEnglishcalledGlobalPositionSystem,throughasimpletranslationwewillbe:"theglobalpositioningsatellitesystem"thisresults.Inthenineteenfiftiesyears,Americansfor30years,spent$about30000000000,theconstructionofsuchabrilliantandhugesystem,canbesaidtobeabrillianthistoryofspaceflight.Figure1GPSnavigationsatelliteBuiltatthebeginningoftheglobalpositioningsystemGPSinspirationwasborninmeridianinstrumentsatellitenavigationsystem,andradialnavigationsystemcannotdisplaythefixed-pointelevation,positionaccuracyandthepositioningtimeunsatisfactoryshortcomingsledtothebirthofGPS.Thissystemconsistsof24satellites,in11hours,58dividedintoperiodicuninterruptedaroundtheearth,asweprovidepictures,data.Althoughsome12000kmaltitude,canbeinsightintoeverycorneroftheearth.Therefore,atfirst,thissetofequipmentisonlyusedinmilitaryandcivilfieldsrelatedtoimportantnationalinterests,givenitsgreatvaluetolaterreallyusedasacivilian,andcompletelyfree.Now,GPSistheproductofmoreemergeinanendlessstream,GPSmobilephone,carGPS,GPSmodule.Then,thelatitudeandlongitudeoftheconceptisalsomoreandmorebefiled,soweshuttleintheearthwillbemoreeasily.2.2GPRSGPRSGerneralPackerRadioServiceEnglish,Chinesetranslationforthecommunicationpacketradioservice.AtpresentthedomesticGPRScarrierisChinamobilecommunication,weoftensendMMSwhenIneedit,saysimply,itisakindofinfinitedatatransmissiontool.Specifically,GPRSintheexistingGSMsystemdevelopedoutofanewpacketdatabearerservice.GPRSandGSMsystemthemostfundamentaldifferenceis,GSMisacircuitswitchingsystem,andGPRSisapacketswitchsystem.GPRSisespeciallysuitableforintermittent,abruptorfrequent,smallamountsofdatatransmission,butalsosuitableforoccasionallargevolumedatatransmission.WecanunderstandtheGSMGPRStoahigherlevel.Figure2GPRSasimplecaseGPRSchargingmethodsandthetraditionalGSMalsohasverybigdifferent,itisonlybydataflowcharging,namelyaccordingtotheusertheamountoftransmitteddatatobilling,forexample,wedownloadedinformation,notbythetimeonlinechargingthatistosay,aslongasthetransmissionofthedata,evenifastraight"online",alsoneednotpayfor.Thenmakea"call"forexample,intheuseofGSM+WAPmobilephoneonline,likethephonestartedcharging;andtheuseofGPRE+WAPonlineismorereasonable,asthephonedoesnotcollectfees,onlydialoguetocalculatecosts.3、Systemoverview3.1ThetargetThesystem'smainpurposeistosolvealargeenterpriseintheproblemofexistence,asfollows:(1)Thelackofaperfectsystem,cannotmasterthevehiclerealtimecondition.(2)Employeesintheworkcannotbetimelyappropriatetransport,leadingtothelackofproductivity.(3)Duetotransporttheinefficientuseoforunauthorizeduse,causethedeclineofproductivity.Inordertosolvetheaboveproblem,weusethesystemmadethefollowingattempt:(1)MoreeasytooperatetheInternetinterface.(2)Anaccepted,alreadyexistingcommunicationsfacilitiesuse.(3)Amoreacceptedbythepeoplereflectthegeographicinformationtotheoperationofthedevice.(4)Openinformationresourcetooluse,reducingthecostofsystem.3.2InformationtechnologyoverviewAtpresent,thereareseveraldifferentformsofthelocatingscheme.Somearebytheservertotheclientforunifiedoperation,someoneachcarwereindependentofthemodeofoperation.Ifweconsiderthecostfactor,theclientserversystemisabettersolution.Ifweconsidertheproblemoftimelinessfactor,independentofthemodeofoperatingsystemadvantage.Thereareothermethods,suchasstrengtheningthegeographicinformationapplication,thisappliestoclientserverenvironment,thissoftwareupgradescanbeinclientserveroperation.Forindependentmode,ifthegeographicinformationneedstobeimproved,itwillneedtolinkeachofthesoftwareupgrade.Atpresent,thereareseveraldifferentformsofthelocatingscheme.Somearebytheservertotheclientforunifiedoperation,someoneachcarwereindependentofthemodeofoperation.Ifweconsiderthecostfactor,theclientserversystemisabettersolution.Ifweconsidertheproblemoftimelinessfactor,independentofthemodeofoperatingsystemadvantage.Thereareothermethods,suchasstrengtheningthegeographicinformationapplication,thisappliestoclientserverenvironment,thissoftwareupgradescanbeinclientserveroperation.Forindependentmode,ifthegeographicinformationneedstobeimproved,itwillneedtolinkeachofthesoftwareupgrade.3.3SystemarchitectureThevehiclepositioningsystemconsideringtheconstraintsandrestrictions,basedontheInternetprovidesasolution.Thesystemdescribedherearchitectureismentionedaboveclientserversystemarchitecture,theclientherereferstothewebbrowser.Inthisarchitecture,theWebserver,communicationserver,databaseserveranddesktopmaptogether,playarolein.Inordertomakethelowestcost,thesystemselectstheopenplatformresourcestoservethedesktopmap.Thissystemusesgeneralpacketradioservice(GPRS)toachievethetrackingunitandclientserverconnection.Generalpacketradioservice(GPRS)isa2.5Gmobilecommunicationtechnology,itisomnipresent.GPRScanalsobeappliedtoacenterpointwithitssurroundingmobiledatatransmissionbetweendevices.UsingGPRScostdependsoneverythousandbytesofdatapassedby,astheSMSinformationcostcalculationmethod.ThroughtheGPScollectionofreal-timelocationinformation,storedintheuserhasacentraldatabase.Thesystemforeachusercangetinformationthroughtheinternet.Figure1showsthearchitectureofthesystem.Fig3systemarchitecture4SystemdesignThissectiondescribesthesystemhardwareandsoftwaredesign,andthefunctionofeachcomponent.4.1HardwaredesignThepositioningsystemthroughtheGPScollectionpositioninginformation,thentheinformationsystemcompressionforaspecificpacketformat,throughtheGPRSandsendittotheserver.IftheGPRScannotreal-timeapplication,hasthetimelabeledpacketisstoredinatemporarystorageunit,suchasGPRSwhenavailable,arestoreddatapacketswillinstantlyupload.Therefore,evenifatransmissionfailure,vehiclereal-timelocationinformationisnotlost.Thepositioningsystembymicrocontroller,GSMmodule,GPSreceiver,thedatastorageunitandapowersupply.Thepositioningdevicediagramasshowninfigure2.Fig4DiagramofpositioningdeviceThemicrocontrolleristhemaincomponentofthepositioningdevice.ItisdirectlythroughtheI/Ointerfacewithothercomponentsconnected.PositioningdeviceofvehicleGPSreceiverthelongitude,latitudeandspeedinformationissenttothemicrocontroller.ThenGSMmodulethroughapreviouslyestablishedGPRSservertransmitsthedatatothemicrocontroller.Firstofall,thedevicerequirestheestablishmentofaconnectedwiththeserverandgeneralpacketradioservice(GPRS),thentheneedtobuildaTCP/IPprotocol,theIPpacketcanbesmoothlytransfer.Positioningdeviceadoptsthedesignofthevehiclebattery,andthebatterydesignintheinsideofthevehicle,isusedasanemergencyanddesign.InGPRSisnotavailable,theGPSdatawillbestoredinthetemporarystorageunit,oncetheGPRSrecoveryeffect,thesestoredGPSdatawillimmediatelybesenttotheserver.Accordingtosomebasicfault,thepositioningdeviceisequippedwithseveralLEDindicatinglamp.TheindicatorshowstheavailabilityofGPS,GPRSavailabilityaswellaspoweravailability.Figure3showstheinnerstructureofpositioningdevice.Fig5theinternalstructureofpositioningdevice4.2SoftwaredesignThesystemsoftwaresystemcomprisesacommunicationserver,webserverandGISdesktopmap.Thepositioningdevicecommunicationserveristhemostimportantpartofitwiththeothercomponentstobeconnected.ThroughthecommunicationserverestablishestheTCP/IPprotocol,therebyandremotehardwaresystemlinking.Communicationservercanbeconnectedthroughthreadsandaclientconnects,customizeanapplicationlevelprotocolcanbeusedtotransferdata.TheserverwillcreateanTCPinterface,theapplicationprograminterfaceconnectedwith,andthentheserverreceivestransmitteddatacomingin.Whenaclient(remotepositioningdevice)toconnect,theserverwillverifyandconfirmtheclient.Thentheserverwillbeginreceivingtheclientinformation,andthestorageserverdatabase.TheWebapplicationwillretrievedatabaseserveraccordingtotherequirementsofuserswithinthedata,anddatapretreatment.TheWebapplicationisthesystemofmainmanagementtools,theuserthroughtheapplicationlogontothesystem,theprogramaccordingtotheuserofthedifferentmodulesoftherequest,toverifyauser'sidentity.5Geographicspatialinformationapplication5.1RelatedgeographicinformationcomponentThesystemofgeographicdatamodulecollectsalltherelevantspatialgeographicinformation.Geographicdatamodulebylocation,geographyedge,routeandrouteordistanceoftravel.Locationsincludethecity,township,includinguserparkinglot,otherlandmarks.Thegeographicaledgereferstoaparticularlocationinthesurroundingregion,theusercandefinetheareaaroundthecenterpointandradius.TheGPSsystemisdefinedbytheregion'scenterposition,andthegeographicaledgereferstothedefinitionoftheradiusoftheregion.Inthispaperapositioningsystem,ifavehicleisdefinedintheregion,itcandetectthelocationof.Routemaycontainmultiplesites.Inacertainroutetoaddalocation,itwillformanewroute.Bythismethod,themainlineandthesecondarylinecanbeaddedtotheroutesystemto.Inordertofacilitateaparticularcarfasterstartingfromthedestination,positioningsystemoperatorscanbedesignedforthespecificline.Whenavehicleneedsinonestroketostay,thesystemoperatorcancombinethepreviousrouteandaddnewstroke,sothatthevehiclecanbenormaloperation.LikeacarneedsfromColombotohurrythat,onthewaytoLavignatotakeaperson.ThistripisthefirstfromtheColomboGalletrunkinColombo-CarterBeasectionsetsout,viaCarterBiya-philiatrunk,thenviaColomboGalletrunkofphilia,Healythetrunk,finallyreachthefountain.Ifacaralongthisroute,oncethetouranydeviation,positioningsystemwillimmediatelyfoundandputthiscaseinshortformofinformationfeedbacktothemanagement.Theenterprisecanthroughtheuseofgeographicinformationtomeettheirrequirements.Lineselectioninterfaceasshowninfigure4.Figure6lineinterfaceManagerscanthroughgeographicinformationmoduletocreatetheirownlocation,geographyedge,routeandtraveldata.Inordertobetteroperationandeasytoobserve,canusethemaptodeterminethelocation,travel,routeandotherrelateddata,thiscanbedonebyabytheelectronicmapconsistingofagraphicaluserinterfacetoachieve.Forexample,candesigntheelectronicmapcordinates,attheclickofthemousetoaparticularposition,setaspecificcitywillberevealed.Onthesystemofcoursedesignisshowninfigure4.5.2Geographicinformationsystemtools--OpenSourceSoftwareInordertomakethepositioningsystempartoftheelectronicmapismoreperfect,thesystemusesacalleddesktopmapofopensourcesoftware.Thegeographicinformationsystemtoolsisawidelyacceptedwiththestandardformatoftheelectronicmap,itcanbeusedtodisplayontheelectronicmapgeographicinformation.DesktopmapontheInternetshowingexcellentdata,suchasmaps,imageandvectordata.Inadditiontobrowsethegeographicinformationsystemdata,theusercanalsothroughthemapbrowserreleasedontheInternetonthegeographiclocationofthepicture.ElectronicmapissavedinaSHPformat,buttheinformationinthedatabaseissavedinDBFformatinthefile.Databaseoftheelectronicmapareatdifferentlevelsinordertosavethe.Wheneverthereisacustomerneedtobrowsethedata,theclientapplicationcanbebasedoncustomerrequirementstoloadthedataatdifferentlevels.Onthepositioningsystemofelectronicpositioningmodule,desktopmapwillgetgeographicinformationsystemdata,thenthedatatogenerateelectronicmap.ThentheserverwillgenerateJPEGformatimagesandtransmitittotheWebserver,userscanbrowsethe.Alloftheelectronicmapisgeneratedinadesktopmap.Inthetransmissionoflocationinformationatthesametime,thepositioningdevicealsothespeed,timeandpowerleveldataistransmittedtotheserver,theinformationisalsostoredinthedatabase.Positioningmoduleaccordingtoeachcar.Thelicenseplatenumbertoallvehiclepositioning.Eachvehicleispositionedvehicleintheelectronicmapisdisplayedtoapoint.Forevery8secondstorefreshthebrowserinterface,thustheycanknowthevehiclereal-timestatus.Themapalsohasageneralelectronicmaphasthefunctions,suchasinthemapaparticularmagnification,andreducetranslationusedinthemodulecanberealized.Thesefunctionscanbrowserthroughtheoutput,thentheimagedisplayed.Figure5showsacarpositioningsystemwithinthedisplayofinformationstatus.Fig7vehiclepositioninginformationdisplay6ConclusionandProspectThispaperintroducesanintegratedgeographicinformationsystem(GIS),combinedwiththeapplicationofglobalpositioningsystem(GPS),generalpacketradioservice(GPRS)andInternetvehiclepositioningsystem.Thissystemistheuseofinformationandcommunicationtechnologycombinedwitheachotherandform.Thesharpriseinfuelprices,thissystemwassuccessfullyusedonacompany'sresourcesforeffectivemanagementofgreathelp.Intheselectionofsupportthepositioningsystemofscienceandtechnologyandthesoftwareandhardwarestructure,somehavethesamepurposeplatformdoresearch.Inconsideringtheimplementationandoperationcostbasis,thesystemselectsapplicationofscienceandtechnologyandthesoftwareandhardwarestructure.Thepositioningsystemintrialoperationofmovingvehicles,real-timepositioning,thepositioningerrordoesnotexceed50meters,intheelectronicmapthesystemclearlydistinguishesbetweentheroadeachamovingcar.WhenGPRSconnectionisbroken,theelectronicmapinformationcanbeupdated.However,oncetheGPRStoestablishaconnection,thedatastoredinthetemporarymemoryquicklyuploadtothedatabase.TheprecisionofthesystemdependslargelyonthecollectedGPSdata,andthereliabilityofthesystemdependsonthemobilecommunicationnetworkreliability.Ifanareaofmobilecommunicationnetworkcoveragerateishigh,sothepositioningsystemcanplayabetterrole.Inenterpriseofvehiclelocationsystem,theclientapplicationshouldbebasedonapersonalcomputer'sWebbrowser.AlthoughThroughthemobileclientoperatingthisapplication,butthepositioningsystemisnotsuitableformobileclientmode.Inthefuture,peoplemaystudythenewpositioningmodule,thesemodulespositionedmaybesuitableformobileusers.Ifthisideacanbeimplemented,peoplewillneedtofocusonwhatcanbeinanappropriatewayinthemobileequipmentstorageandmapping.7ThanksThankstoDialogTelekomLtdonthehelp.8Thereferenceliterature[1]蔣文怡．GSM短消息傳輸時(shí)延及其對(duì)GPS定位數(shù)據(jù)傳輸?shù)挠绊懀苿?dòng)通信.2001．2．p32-35[2]李建平，閆科，熊修波.GPS車輛監(jiān)控系統(tǒng)設(shè)計(jì)與實(shí)現(xiàn)技術(shù).長(zhǎng)沙大學(xué)學(xué)報(bào)2001.V01.15(i).p14-19[3]唐依珠，鄭茜穎，黃金虎.GPS車輛導(dǎo)航系統(tǒng)的研究和開(kāi)發(fā).福州大學(xué)學(xué)報(bào)2001.V01.29(2).p16-19[4]張勤，李家權(quán)等.GPS測(cè)量原理及應(yīng)用.北京.科學(xué)出版社.2005.p32-50[5]譚國(guó)真.車輛定位與導(dǎo)航系統(tǒng).北京.電子工業(yè)出版社.1999.p68-120[6]韓斌杰.GPRS原理及其網(wǎng)絡(luò)優(yōu)化.北京.機(jī)械工業(yè)出版社.2003.p59-76[7]GregGerten.Protectingtheglobalpositioningsystem.InternationalcA3nferellcaonintegratednavigateonsystems.St[8]呂捷.GPRS技術(shù).北京北京郵電大學(xué)出版社.2001.p34-37[9]蔣文怡,王虹英,鐘章隊(duì)..GSM短消息傳輸時(shí)延及其對(duì)GPS定位數(shù)據(jù)傳輸?shù)挠绊?移動(dòng)通信.2001(2).p24-25[10]彭志煜.GPS/GSM移動(dòng)目標(biāo)監(jiān)控系統(tǒng)簡(jiǎn)介.現(xiàn)代通信.2000(8).p66-69[11]Siemens.ATCOMMANDSETSiemensModuleCellularEngines.TC35Module.2001(5)p88-188[12]楊留清,張閩申徐菊英.數(shù)字移動(dòng)通信系統(tǒng).北京人民郵電出版社.1995.p64-67[13]ElliottDKaplan.GPS原理與應(yīng)用[M].北京:電子工業(yè)出版社.2001.p89-93[14]andandChallengesinEmbeddedSystems[J].IEEEMicro,p8-9,July-August2004[15]胡健.單片機(jī)原理及接口技術(shù)[M].北京：機(jī)械工業(yè)出版社.2005.p164-191.[16]Atmelcooperation,Atmel8bitAVRMicrocontrollerwith64kBytesinSystemprogrammableflash.[17]iWOWConnectionsPteLtd,iWowGP-810GPSModuleproducthardwaretechnicalspecification,released22ndMarch2006,documentversion1.1[18]MapserverWWWdocument,://.Visited15thNovember2007.[19]MichaelWorboys,MattDuckham,GIS:AComputingPerspective,2ndEdition,CRCPress,2004.[20]NimalikaFernando,SirimevanWidyasekera,LalithGamage,DileekaDias“StudyonfeasibilityofpracticaluseoflowcostGIStoolsinthecontextofSriLankaforpreparationanddistributionofdigitalspatialdata〞AnnualConferenceoftheComputerSocietyofSriLanka,2007.[21]ThinkinginGIS,-for-c-mapscript-asp-net,Visited20thJanuary2023.英文文獻(xiàn)翻譯基于GPS、GPRS、GIS和互聯(lián)網(wǎng)的車輛定位系統(tǒng)摘要本文介紹了綜合地理信息系統(tǒng)〔GIS〕,聯(lián)合應(yīng)用全球定位系統(tǒng)〔GPS〕,通用分組無(wú)線業(yè)務(wù)〔GPRS〕和互聯(lián)網(wǎng)的車輛定位系統(tǒng)。對(duì)于一個(gè)需要研究與管理車輛定位的企業(yè)來(lái)說(shuō)，選取一個(gè)適宜的車輛定位系統(tǒng)是非常重要的。該系統(tǒng)的主要特點(diǎn)是采用開(kāi)放式的地理信息系統(tǒng)平臺(tái)來(lái)獲取資源，使用基于互聯(lián)網(wǎng)的用戶界面，實(shí)現(xiàn)車輛定位信息的實(shí)時(shí)更新。該系統(tǒng)由基于GPS定位車輛的設(shè)備、通訊效勞器、網(wǎng)絡(luò)效勞器、數(shù)據(jù)庫(kù)效勞器以及桌面地圖組成。定位設(shè)備安裝在車輛內(nèi)部，通過(guò)GPS定位來(lái)收集實(shí)時(shí)信息，這些信息不斷通過(guò)GPRS傳輸?shù)街醒霐?shù)據(jù)庫(kù)。用戶可以通過(guò)互聯(lián)網(wǎng)實(shí)時(shí)查看當(dāng)前每輛車的位置，進(jìn)而對(duì)所有車輛進(jìn)行管理。車輛位置及其他相關(guān)信息會(huì)顯示在由桌面地圖所生成的一張電子地圖上。本系統(tǒng)是利用信息和通信技術(shù)的相互結(jié)合而形成的。在燃料價(jià)格急劇攀升時(shí)，此系統(tǒng)的成功運(yùn)用對(duì)一個(gè)公司的資源進(jìn)行有效管理有很大幫助。關(guān)鍵詞：全球定位系統(tǒng)〔GPS〕；通用分組無(wú)線業(yè)務(wù)(GPRS)；車輛定位；桌面地圖；互聯(lián)網(wǎng)；信息通信技術(shù)1導(dǎo)論本文所提出的車輛定位系統(tǒng)綜合運(yùn)用了現(xiàn)代信息技術(shù)和通信技術(shù)，適用于擁有多輛車輛的企業(yè)，企業(yè)可以運(yùn)用此系統(tǒng)對(duì)車輛進(jìn)行追蹤與管理。該系統(tǒng)由車載跟蹤裝置，中央效勞器系統(tǒng)及互聯(lián)網(wǎng)組成。通過(guò)這個(gè)系統(tǒng)，用戶可以運(yùn)用手中電腦操控桌面地圖，進(jìn)而了解車輛的地理位置及其它相關(guān)信息。本文著重研究了車輛定位系統(tǒng)在設(shè)計(jì)與開(kāi)展方面的情況。然而，該系統(tǒng)還有很多別的單元組成，包括管理資源系統(tǒng)〔司機(jī)，車輛等〕，高效利用〔車輛分配問(wèn)題〕以及報(bào)告生成和審計(jì)活動(dòng)等組成局部。該系統(tǒng)設(shè)計(jì)的目的是為了效勞于擁有大型車隊(duì)或者對(duì)車輛有復(fù)雜的使用要求的企業(yè)。員工可能需要頻繁的使用短途行程，以及一些長(zhǎng)途旅行。有些行程可能短時(shí)間內(nèi)就可以確定，而有些行程可能會(huì)需要配之相應(yīng)的日常時(shí)間表。員工有時(shí)可能會(huì)需要延長(zhǎng)行程或者中途停車，可是車輛維修經(jīng)常會(huì)滿足不了臨時(shí)需求。這些問(wèn)題都需要一個(gè)更為有效的車輛定位系統(tǒng)來(lái)解決，為了滿足上述要求，需要一種多元化的策略。因此要想提高一家公司整體的生產(chǎn)力，必須對(duì)所有車輛進(jìn)行集中化管理。本文綜合運(yùn)用了多種技術(shù)來(lái)實(shí)現(xiàn)這個(gè)目標(biāo)。下面的案例展示了：我們可以把多種科學(xué)技術(shù)結(jié)合起來(lái)去解決一個(gè)現(xiàn)實(shí)問(wèn)題。2GPS和GPRS的定義2.1GPSGPS的英文全稱為GlobalPositionSystem，通過(guò)簡(jiǎn)單的翻譯之后我們便得到了：“全球衛(wèi)星定位系統(tǒng)〞這樣的結(jié)果。從20世紀(jì)50年代后期開(kāi)始，美國(guó)人用了30年，花了300多億美金，建造了如此一個(gè)輝煌龐大的系統(tǒng)，可以說(shuō)是航天史上輝煌的一筆。圖1GPS導(dǎo)航衛(wèi)星初建GPS全球定位系統(tǒng)的靈感誕生于子午線儀衛(wèi)星導(dǎo)航系統(tǒng)，而子午線儀衛(wèi)星導(dǎo)航系統(tǒng)無(wú)法顯示定點(diǎn)高程、定位精度與定位時(shí)間不如人意的缺點(diǎn)促使了GPS的誕生。這套系統(tǒng)由24顆衛(wèi)星組成，以11小時(shí)58分為周期不間斷的圍繞著地球轉(zhuǎn)動(dòng)，為我們提供圖片、數(shù)據(jù)。雖然遠(yuǎn)在12000公里的高空，卻可以洞察地球上的每個(gè)角落。因此，起初這套設(shè)備僅僅是用于軍事和涉及國(guó)家重要利益的民用領(lǐng)域，鑒于它的巨大價(jià)值后來(lái)才真正用作民用，并且完全免費(fèi)。現(xiàn)如今，GPS產(chǎn)品更是層出不窮，GPS、車載GPS、GPS2.2GPRSGPRS是GernerralPackerRadioService的英文縮寫(xiě)，中文譯為通信無(wú)線分組業(yè)務(wù)。目前國(guó)內(nèi)的GPRS運(yùn)營(yíng)商是中國(guó)移動(dòng)通信，其實(shí)我們經(jīng)常在發(fā)彩信的時(shí)候用到它，簡(jiǎn)單的說(shuō)，它是無(wú)限數(shù)據(jù)的一種傳輸工具。具體來(lái)講，GPRS是在現(xiàn)有的GSM系統(tǒng)上開(kāi)展出來(lái)的一種新的分組數(shù)據(jù)承載業(yè)務(wù)。GPRS與GSM系統(tǒng)最根本的區(qū)別是，GSM是一種電路交換系統(tǒng)，而GPRS是一種分組交換系統(tǒng)。GPRS特別適用于間斷的、突發(fā)性的或頻繁的、少量的數(shù)據(jù)傳輸，也適用于偶爾的大數(shù)據(jù)量傳輸。我們可以將GPRS理解為GSM的一個(gè)更高層次。圖2GPRS簡(jiǎn)單應(yīng)用案例GPRS的收費(fèi)方式和傳統(tǒng)的GSM也有很大不同，它僅按數(shù)據(jù)流量計(jì)費(fèi)，即根據(jù)用戶傳輸?shù)臄?shù)據(jù)量來(lái)計(jì)費(fèi)，例如，我們?cè)诰W(wǎng)上下載信息時(shí)，不是按上網(wǎng)時(shí)間計(jì)費(fèi)也就是說(shuō)，只要不進(jìn)行數(shù)據(jù)傳輸，就算一直“在線〞，也無(wú)需付費(fèi)。再做個(gè)“打〞的比方，在使用GSM+WAP上網(wǎng)時(shí)，就好比接通便開(kāi)始計(jì)費(fèi)；而使用GPRE+WAP上網(wǎng)那么要合理得多，就像接通并不收費(fèi)，只有對(duì)話時(shí)才計(jì)算費(fèi)用。3系統(tǒng)概述3.1目標(biāo)此系統(tǒng)的主要目的是為了解決一個(gè)大型企業(yè)中存在的問(wèn)題，如下：(1)缺乏一套完善的制度，不能掌握車輛的實(shí)時(shí)情況。(2)員工在工作時(shí)不能及時(shí)運(yùn)用適宜交通工具，導(dǎo)致生產(chǎn)力的缺失。(3)由于交通工具的低效使用或者未授權(quán)使用，導(dǎo)致生產(chǎn)力的下降。為了解決上述問(wèn)題，人們運(yùn)用該系統(tǒng)做出了如下嘗試：(1)更易于操作的互聯(lián)網(wǎng)界面。(2)一種被人們普遍接受的、已經(jīng)存在的通信設(shè)施的運(yùn)用。(3)一種更易被人們接受的反映地理信息的設(shè)備的運(yùn)用。(4)開(kāi)放式信息資源工具的運(yùn)用，減少了系統(tǒng)本錢。3.2信息技術(shù)概述目前，有幾種不同形式的定位方案。有些是由客戶端效勞器進(jìn)行統(tǒng)一操作，有些是對(duì)每輛車進(jìn)行獨(dú)立模式的操作。如果考慮本錢因素，客戶端效勞器系統(tǒng)是一個(gè)更好的解決方案。如果考慮問(wèn)題解決及時(shí)性的因素，獨(dú)立模式的操作系統(tǒng)占據(jù)優(yōu)勢(shì)。還有其他的解決方法，比方加強(qiáng)對(duì)地理信息的運(yùn)用，這種情況適用于客戶端效勞器環(huán)境，這種軟件升級(jí)可以在客戶端效勞器上進(jìn)行操作。而對(duì)于獨(dú)立模式，如果地理信息需要得到改善，那么需要對(duì)每個(gè)環(huán)節(jié)的軟件都進(jìn)行升級(jí)。一些定位系統(tǒng)效勞供給商把定位信息保存在自己的信息數(shù)據(jù)庫(kù)中。如果用戶訪問(wèn)這些信息，有時(shí)甚至需要用到國(guó)際電信根底設(shè)施以外的付費(fèi)訪問(wèn)。而由移動(dòng)網(wǎng)絡(luò)提供的短消息效勞〔SMS〕是該系統(tǒng)中信息傳遞的另外一種方式。在這些系統(tǒng)中，用戶運(yùn)用信息的靈活性很低，而且還要承受相對(duì)較高的本錢。3.3系統(tǒng)架構(gòu)該車輛定位系統(tǒng)綜合考慮了上述制約因素和限制條件，提供了一種基于互聯(lián)網(wǎng)的解決方案。這里描述的系統(tǒng)架構(gòu)是上面所提到的客戶效勞端系統(tǒng)架構(gòu)，這里的客戶就是指網(wǎng)絡(luò)瀏覽器。在此架構(gòu)中，Web效勞器、通信效勞器，數(shù)據(jù)庫(kù)效勞器和桌面地圖綜合起來(lái)，發(fā)揮作用。為了使本錢最低，該系統(tǒng)選擇開(kāi)放式的資源平臺(tái)來(lái)效勞于桌面地圖。該系統(tǒng)選用通用分組無(wú)線業(yè)務(wù)〔GPRS〕來(lái)實(shí)現(xiàn)跟蹤單位與客戶效勞端的連接。通用分組無(wú)線業(yè)務(wù)〔GPRS〕是一種2.5G的移動(dòng)通信技術(shù)，它無(wú)所不在。GPRS還可以運(yùn)用于一個(gè)中心點(diǎn)同它周邊移動(dòng)設(shè)備間的數(shù)據(jù)傳輸。運(yùn)用GPRS的本錢取決于每千字節(jié)所傳遞的數(shù)據(jù)，正如SMS中每條信息費(fèi)用的計(jì)算方法。通過(guò)GPS收集的實(shí)時(shí)定位信息，存放于用戶所擁有的中央數(shù)據(jù)庫(kù)中。該系統(tǒng)的每個(gè)用戶都可以通過(guò)互聯(lián)網(wǎng)獲取信息。圖1說(shuō)明了此系統(tǒng)的架構(gòu)。圖3系統(tǒng)架構(gòu)4系統(tǒng)設(shè)計(jì)本節(jié)介紹了該系統(tǒng)硬件和軟件的設(shè)計(jì)，同時(shí)還有每個(gè)組件的功能。4.1硬件設(shè)計(jì)該定位系統(tǒng)通過(guò)GPS收集定位信息，接著把信息系統(tǒng)壓縮為一個(gè)特定的數(shù)據(jù)包格式，通過(guò)GPRS把它發(fā)送到效勞器。如果GPRS不能實(shí)時(shí)應(yīng)用，擁有時(shí)間標(biāo)記的數(shù)據(jù)包就會(huì)被存儲(chǔ)在一個(gè)臨時(shí)存儲(chǔ)單元內(nèi)，等GPRS可用時(shí)，被存儲(chǔ)的數(shù)據(jù)包會(huì)即時(shí)上傳。因此，即使一次傳輸失敗，車輛的實(shí)時(shí)定位信息也不會(huì)喪失。該定位系統(tǒng)由微控制器、GSM模塊、GPS接收器、數(shù)據(jù)存儲(chǔ)單元和電源組成。該定位裝置框圖如圖4所示。圖4定位裝置框圖微控制器是該定位裝置的主要組件。它直接通過(guò)I/O接口與其他組件連接。定位裝置中的GPS接收器將車輛所處的經(jīng)度、緯度以及速度信息發(fā)送到微控制器。接著GSM模塊通過(guò)以前建立的GPRS效勞器把這些數(shù)據(jù)傳送到微控制器。首先，該裝置需要建立一個(gè)與效勞器相連接的通用分組無(wú)線業(yè)務(wù)〔GPRS〕,接著需要建立一個(gè)TCP/IP協(xié)議，使得IP數(shù)據(jù)包可以順利的傳遞。定位裝置的設(shè)計(jì)采用車載電池，而車載電池設(shè)計(jì)在車體內(nèi)部，是作為緊急備用而設(shè)計(jì)的。在GPRS不可用的情況下，GPS數(shù)據(jù)會(huì)存于臨時(shí)存儲(chǔ)單元中，一旦GPRS恢復(fù)作用，這些存儲(chǔ)的GPS數(shù)據(jù)就會(huì)即刻被傳送到效勞器端。針對(duì)一些根本故障，此定位裝置配有幾個(gè)LED指示燈。這些指示燈顯示了GPS可用性，GPRS可用性以及電源可用性。圖5顯示了該定位裝置的內(nèi)外結(jié)構(gòu)。圖5定位裝置內(nèi)部結(jié)構(gòu)4.2軟件設(shè)計(jì)該系統(tǒng)的軟件系統(tǒng)包括通信效勞器、網(wǎng)絡(luò)效勞器和GIS桌面地圖。通信效勞器是該定位裝置中最為重要的局部，它同其他組件進(jìn)行連接。通過(guò)通信效勞器建立TCP/IP協(xié)議，從而與遠(yuǎn)程硬件系統(tǒng)連接起來(lái)。通信效勞器可以通過(guò)多線程與多個(gè)客戶端連接起來(lái)，自定義一個(gè)應(yīng)用程序級(jí)協(xié)議可以用來(lái)傳輸數(shù)據(jù)。效勞器會(huì)自行創(chuàng)立一個(gè)TCP接口，會(huì)把應(yīng)用程序同接口連接起來(lái)，接著此效勞器可以接收傳送進(jìn)來(lái)的數(shù)據(jù)。當(dāng)一個(gè)客戶端〔遠(yuǎn)程定位裝置〕試圖進(jìn)行連接時(shí)，效勞器將會(huì)驗(yàn)證和確認(rèn)該客戶端。接著效勞器將開(kāi)始接收客戶端傳送的信息，并存儲(chǔ)效勞器中的數(shù)據(jù)庫(kù)內(nèi)。Web應(yīng)用程序會(huì)根據(jù)用戶要求檢索數(shù)據(jù)庫(kù)效勞器內(nèi)的數(shù)據(jù)，并且對(duì)數(shù)據(jù)進(jìn)行預(yù)處理。Web應(yīng)用程序也是該系統(tǒng)中的主要管理工具，用戶通過(guò)此應(yīng)用程序登錄該系統(tǒng)，該程序根據(jù)用戶對(duì)不同模塊的要求，來(lái)驗(yàn)證用戶的身份。5地理空間信息的應(yīng)用5.1有關(guān)地理信息的組成局部該系統(tǒng)的地理數(shù)據(jù)模塊收集了所有相關(guān)的空間地理信息。地理數(shù)據(jù)模塊由地點(diǎn)、地理邊緣、路線和行程組成。地點(diǎn)包括城市、鄉(xiāng)鎮(zhèn)、包括用戶停車場(chǎng)在內(nèi)的其他標(biāo)志性建筑。地理邊緣是指某一特定地點(diǎn)的周邊區(qū)域，使用者可以界定此周邊區(qū)域的中心點(diǎn)及半徑。GPS系統(tǒng)處于所界定區(qū)域的中心位置，而地理邊緣就是指此界定區(qū)域的半徑。在本文研究的定位系統(tǒng)中，如果某車輛處于界定區(qū)域內(nèi)，那么就可以檢測(cè)到其位置。路線中可能會(huì)包含多個(gè)地點(diǎn)。在某條路線中新增一個(gè)地點(diǎn)，就會(huì)形成一條新的路線。通過(guò)這種方法，主要線路和次要線路都可以參加到路線系統(tǒng)中去。為了方便一輛特定汽車更快捷的從出發(fā)地到達(dá)目的地，定位系統(tǒng)的操作人員可以為其設(shè)計(jì)特定線路。當(dāng)某一車輛需要在一次行程中作停留時(shí)，系統(tǒng)操作員就可以結(jié)合以前路線并參加新的行程，從而使車輛可以正常運(yùn)行。比方一輛車需要從科倫坡出發(fā)去赫利那，在途中還需要去拉維尼亞接一個(gè)人。這次行程就是首先從科倫坡加勒干線中的科倫坡—卡特比亞路段出發(fā)，途經(jīng)卡特比亞—菲利亞干線，接著經(jīng)過(guò)科倫坡加勒干線中的菲利亞—赫利那干線，最后到達(dá)赫利那。如果一輛車沿著此路線行駛，一旦行程中出現(xiàn)任何偏差，定位系統(tǒng)就會(huì)立刻發(fā)現(xiàn)并且把此情況以短信息形式回饋給管理人員。企業(yè)可以通過(guò)上述方式利用地理信息滿足自身要求。線路選擇的接口如圖6所示。圖6線路接口管理人員可以通過(guò)地理信息模塊創(chuàng)立屬于自己的地點(diǎn)、地理邊緣、路線與行程等數(shù)據(jù)信息。為了更好的操作和易于觀察，可以使用地圖來(lái)確定地點(diǎn)、行程、路線等相關(guān)數(shù)據(jù)，這個(gè)可以通過(guò)一種由電子地圖組成的圖形用戶界面實(shí)現(xiàn)。例如可以設(shè)計(jì)電子地圖上的坐標(biāo)，在鼠標(biāo)點(diǎn)擊某一特定位置時(shí)，設(shè)置的特定城市就會(huì)顯現(xiàn)出來(lái)。關(guān)于此系統(tǒng)中的路線設(shè)計(jì)如圖4所示。5.2地理信息系統(tǒng)工具-開(kāi)源軟件為了使定位系統(tǒng)的電子地圖局部更為完善，該系統(tǒng)運(yùn)用了一種叫做桌面地圖的開(kāi)源軟件。這種地理信息系統(tǒng)工具