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Aninternet-basedlogisticsmanagementsystemforenterprisechainsN.Prindezis,C.T.KiranoudisSchoolofChemicalEngineering,NationalTechnicalUniversity,15780Athens,GreeceReceived13September2003;receivedinrevisedform20December2003;accepted27January2004Availableonline10December2004.Developingtheinternet-basedapplicationtoolWebservicesoffernewopportunitiesinbusinesslandscape,facilitatingaglobalmarketplacewherebusinessrapidlycreateinnovativeproductsandservecustomersbetter.Whateverthatbusinessneedsis,Webserviceshavetheflexibilitytomeetthedemandandallowtoaccelerateoutsourcing.Inturn,thedevelopercanfocusonbuildingcorecompetenciestocreatecustomerandshareholdervalue.ApplicationdevelopmentisalsomoreefficientbecauseexistingWebservices,regardlessofwheretheyweredeveloped,caneasilybereused.ManyofthetechnologyrequirementsforWebservicesexisttoday,suchasopenstandardsforbusinessto-businessapplications,mission-criticaltransactionplatformsandsecureintegrationandmessagingproducts.However,toenablerobustanddynamicintegrationofapplications,theindustrystandardsandtoolsthatextendthecapabilitiesoftodaysbusiness-to-businessinteroperabilityarerequired.ThekeytotakingfulladvantageofWebservicesistounderstandwhatWebservicesareandhowthemarketislikelytoevolve.Oneneedstobeabletoinvestinplatformsandapplicationstodaythatwillenablethedevelopertoquicklyandeffectivelyrealizethesebenefitsaswellastobeabletomeetthespecificneedsandincreasebusinessproductivity.Typically,therearetwobasictechnologiestobeimplementedwhendealingwithinternet-basedapplications;namelyserver-basedandclient-based.Bothtechnologieshavetheirstrongpointsregardingdevelopmentofthecodeandthefacilitiestheyprovide.Server-basedapplicationsinvolvethedevelopmentofdynamicallycreatedwebpages.ThesepagesaretransmittedtothewebbrowseroftheclientandcontaincodeintheformofHTMLandJAVASCRIPTlanguage.TheHTMLpartisthestaticpartofthepagethatcontainsformsandcontrolsforuserneedsandtheJAVASCRIPTpartisthedynamicpartofthepage.Typically,thestructureofthecodecanbecompletelychangedthroughtheinterventionofwebservermechanismsaddedonthetransmissionpartandimplementedbyserver-basedlanguagessuchasASP,JSP,PHP,etc.Thiscomestothedevelopmentofanintegrateddynamicpageapplicationwhereuserdesireregardingproblempeculiarities(calculatingshortestpaths,executeroutingalgorithms,transactwiththedatabase,etc.)isimplementedbyappropriatelyinvokingdifferentpartsofthedynamiccontentofsuchpages.Inserver-basedapplicationsallcalculationsareexecutedontheserver.Inclient-basedapplications,JAVAappletsprevail.Communicationoftheuserisguaranteedbythewell-knownJAVAmechanismthatactsasthemediumbetweentheuserandcode.Everythingisexecutedontheclientside.Datainthiscasehavetoberetrieved,onceandthismightbethetime-consumingpartofthetransaction.Inserver-basedapplications,serverresourcesareusedforallcalculationsandthisrequirespowerfulserverfacilitieswithrespecttohardwareandsoftware.Client-basedapplicationsareburdenedwithdatatransmission(chieflyrelatedtoroadnetworkdata).Thereisaremedytothat;namelycaching.Onceloaded,theyareleftinthecachearchivesofthewebbrowsertobeinstantlyrecalledwhenneeded.Inourcase,aclient-basedapplicationwasdeveloped.Themainreasonwasthedemandfromtheuserspointofviewforpersonaldatadiscretionregardingtheirclients.Infact,thisinformationwaskeptsecretinoursystemevenfromtheserversideinvolved.Datamanagementplaysmajorroleinthegoodfunctionofoursystem.Thisrolebecomesmoresubstantialwhenthedistributiontakesplacewithinalargeanddetailedroadnetworklikethisofamajorcomplexcity.Morespecifically,inordertoproducetheproposedtheroutingplan,thesystemusesinformationabout:thelocationsofthedepotandthecustomerswithintheroadnetworkofthecity(theirco-ordinatesattachedinthemapofthecity),thedemandofthecustomersserviced,thecapacityofthevehiclesused,thespatialcharacteristicsofroadsegmentsofthenetworkexamined,thetopographyoftheroadnetwork,thespeedofthevehicle,consideringthespatialcharacteristicsoftheroadandtheareawithinofwhichismoved,thesynthesisofthecompanyfleetofvehicles.Consequently,thesystemcombines,inrealtime,theavailablespatialcharacteristicswithallotherinformationmentionedabove,andtoolsformodelling,spatial,non-spatial,andstatisticalanalysis,imageprocessingformingascalable,extensibleandinteroperableapplicationenvironment.Thevalidationandverificationofaddressesofcustomersensuretheaccurateestimationoftraveltimesanddistancestravelled.Inthecaseofboundaryinthetotalrouteduration,underestimatesoftraveltimemayleadtofailureoftheprogrammedroutingplanwhereasoverestimatescanlowertheutilizationofdriversandvehicles,andcreateunproductivewaittimesaswell(Assad,1991).Thedatacorrespondingtotheareaofinterestinvolvedtwodifferentdetails.Amoredetailednetwork,appropriatelyforgeocoding(approximately250,000links)andalessdetailedforrouting(about10,000links).Thetwonetworksoverlappedexactly.Thetoolthatprovidessolutionstoproblemsofeffectivelydeterminingtheshortestpath,expressedintermsoftraveltimeordistancetravelled,withinaspecificroadnetwork,usingtheDijkstra’salgorithm(Winston,1993).Inparticular,theDijks