简介:WeconsideranMX/G/1queueingsystemwithtwophasesofheterogeneousserviceandBernoullivacationschedulewhichoperateunderalinearretrialpolicy.Inaddition,eachindividualcustomerissubjecttoacontroladmissionpolicyuponthearrival.ThismodelgeneralizesboththeclassicalM/G/1retrialqueuewitharrivalsinbatchesandatwophasebatcharrivalqueuewithasinglevacationunderBernoullivacationschedule.Wewillcarryoutanextensivestationaryanalysisofthesystem,includingexistenceofthestationaryregime,embeddedMarkovchain,steadystatedistributionoftheserverstateandnumberofcustomerintheretrialgroup,stochasticdecompositionandcalculationofthefirstmoment.
简介:Earlydiagnosisandtreatmentisthekeytoimprovingtheprognosisofgastriccancer.Thepastdecadeshavewitnessedtherapidadvancesinthediagnosisandmanagementofearlygastriccancer(EGC):endoscopyhasplayedanincreasinglyimportantrole,whereaslaparoscopictechniqueshavealsobeenintroducedforEGCtreatment.InChina,the
简介:Sport-relatedconcussionisacommonneurologicalinjurythatoccursinalllevelsofathleticparticipation.Concussionsmayactuallygoundiagnosed,astheydonotalwaysdisplayoutwardsignsandathletesmayfailtoreportsymptomsofconcussion,eitherbecausetheydonotknowthesymptoms,orforfearofremovalfromplay.Inappropriatemanagementofconcussioncanleadtoincreasedriskofsubsequentinjury.Thisarticleoutlinesvariousaspectsofsport-relatedconcussionmanagement,includingpreparation/planning,education,evaluation,management,returntoplaydecisions,andlongtermeffectsofconcussion.Preparationandeducationarethefirststepsthatmustbetakentominimizethepotentiallynegativeconsequencesofconcussion.Ifaconcussionissuspected,itmustbestressedthattheevaluationshouldincludeamultifacetedapproach,withaphysicalexaminationandassessmentofsignsandsymptoms,neurocognitionandbalance.Themanagementofconcussionshouldincludebothphysicalandcognitiverestandfactorssuchastransportation,sleep,work,andacademicsshouldbetakenintoconsideration.Returntoplayfollowingconcussionshouldfollowagraduatedreturntoplayprotocol,withcarefulmonitoringofsymptoms.Sportsmedicinecliniciansshouldstayuptodatewithinformationregardingconcussionmanagementandtakeaconservativeapproach,becausetherearerecentreportsofvariouscumulativeeffectsofmultipleconcussions.
简介:Thisarticlepresentsadatamanagementsolutionbasedonthedatadistributionservice(DDS)communicationmodel.ThebasicDDScommunicationmodelconsistsofaunidirectionaldataexchangewhereapplicationsthatpublishdata'push'therelevantdata,whichisupdatedtothelocalcachesofco-locatedsubscriberstothedata[1].DDShasnospecifiedcenternodetoforwarddatapacketsandmaintainthecommunicationdata.Thistypeofpublish-subscribe(P/S)modelpresentsintegrityandconsistencychallengesindatamanagement.Unlikepeer-to-peer(P2P)distributedstorage,DDSapplicationshaveahardreal-timeenvironmentandfewerdatafeatures,andthecoreproblemisensuringtheintegrityandconsistencyofdataindistributedsystemsunderthishardreal-timeenvironment.ThisarticlebeginswithabriefintroductionofthecommunicationmodelusedbyDDS,thenanalyzespersistentdatamanagementproblemscausedbysuchmodel,andprovidesanappropriatesolutiontotheseproblems.Thissolutionhasbeenimplementedinaprototypesystemofthereal-timeservicebus(RTSB)ofTsinghuaUniversity.
简介:Surfacequalityhasbeenoneofthekeyfactorsinfluencingtheongoingimprovementofthequalityofsteel.Therefore,itisurgenttoprovidemethodsforefficientsupervisionofsurfacedefects.Thispaperfirstexpressedthemainproblemsexistingindefectmanagementandthenfocusedonconstructingadataplatformofsurfacedefectmanagementusingamultidimensionaldatabase.Finally,someon-lineapplicationsoftheplatformatBaosteelweredemonstrated.Resultsshowthattheconstructedmultidimensionaldatabaseprovidesmorestructureddefectdata,andthusitissuitableforswiftandmulti-angleanalysisofthedefectdata.