简介:ThisstudyconcernssecurityissuesoftheemergingWirelessBodySensorNetwork(WBSN)formedbybiomedicalsensorswornonorimplantedinthehumanbodyformobilehealthcareappli-cations.Anovelauthenticatedsymmetric-keyestablishmentschemeisproposedforWBSN,whichfullyexploitsthephysiologicalfeaturesobtainedbynetworkentitiesviathebodychannelavailableinWBSNbutnototherwirelessnetworks.Theself-definedIntrinsicSharedSecret(ISS)isusedtoreplacethepre-deploymentofsecretsamongnetworkentities,whichthuseliminatescentralizedservicesorau-thoritiesessentialinexistingprotocols,andresolvesthekeytransportprobleminthepuresymmet-ric-keycryptosystemforWBSNaswell.Thesecuritypropertiesoftheproposedschemearedemon-stratedintermsofitsattackcomplexityandthetypesofattacksitcanresist.Besides,theschemecanbeimplementedunderalight-weightwayinWBSNsystems.DuetotheimportanceoftheISSconcept,theanalysisonusingfalseacceptance/falserejectionmethodtoevaluatetheperformanceofISSforitsusageintheschemeisalsodemonstrated.
简介:Recently,ithasbeenseenthattheensembleclassifierisaneffectivewaytoenhancethepredictionperformance.However,itusuallysuffersfromtheproblemofhowtoconstructanappropriateclassifierbasedonasetofcomplexdata,forexample,thedatawithmanydimensionsorhierarchicalattributes.Thisstudyproposesamethodtoconstructeanensembleclassifierbasedonthekeyattributes.Inadditiontoitshigh-performanceonprecisionsharedbycommonensembleclassifiers,thecalculationresultsarehighlyintelligibleandthuseasyforunderstanding.Furthermore,theexperimentalresultsbasedontherealdatacollectedfromChinaMobileshowthatthekey-attributes-basedensembleclassifierhasthegoodperformanceonbothoftheclassifierconstructionandthecustomerchurnprediction.
简介:Histogramofcollineargradient-enhancedcoding(HCGEC),arobustkeypointdescriptorformulti-spectralimagematching,isproposed.TheHCGECmainlyencodesroughstructureswithinanimageandsuppressesdetailedtexturalinformation,whichisdesirableinmulti-spectralimagematching.Experimentsontwomulti-spectraldatasetsdemonstratethattheproposeddescriptorcanyieldsignificantlybetterresultsthansomestate-ofthe-artdescriptors.
简介:Timeefficiencyofkeyestablishmentandupdateisoneofthemajorproblemscontributorykeymanagementsstrivetoaddress.Toachievebettertimeefficiencyinkeyestablishment,weproposeaLocation-basedHuffman(L-Huffman)scheme.First,usersareseparatedintoseveralsmallgroupstominimizecommunicationcostwhentheyaredistributedoverlargenetworks.Second,bothuser'scomputationdifferenceandmessagetransmissiondelayaretakenintoconsiderationwhenHuffmancodingisemployedtoformingtheoptimalkeytree.Third,thecombinedweightsinHuffmantreearelocatedinahigherplaceofthekeytreetoreducethevarianceoftheaveragekeygenerationtimeandminimizethelongestkeygenerationtime.SimulationsdemonstratethatL-HuffmanhasmuchbetterperformanceinwideareanetworksandisalittlebetterinlocalareanetworkthanHuffmanscheme.
简介:Certificatelessencryptionattractsalotofattentionsofarbyeliminatingthekeyescrowprobleminidentity-basedencryptionandpublickeycertificatesinthetraditionalpublickeycryptography.Byconsideringthethreatfromthekeyexposure,itisdesirabletoincorporatetheideaofkey-insulatedcryptosystemintothecertificatelessencryption.Inthispaper,wehavedesignedanefficientcertificatelesskeyinsulatedencryption(CL-KIE)schemetoachievethisgoal.Byourapproach,thecomputationalperformanceofourschemehasbeenimprovedsignificantlyintermsofreductiononrunningtimeandstorage.WealsogavethesecurityproofofthenewCL-KIEschemeagainstthechosenplaintextattacks(CPAs)intherandomoracle,consideringtheassumptionofthecomputationalDiffie-Hellman(CDH)problem.
简介:Nowadays,thepassword-basedremoteuserauthenticationmechanismusingsmartcardisoneofthesimplestandconvenientauthenticationwaystoensuresecurecommunicationsoverthepublicnetworkenvironments.Recently,Liuetal.proposedanefficientandsecuresmartcardbasedpasswordauthenticationscheme.However,wefindthatLiuetal.’sschemeisvulnerabletotheoff-linepasswordguessingattackanduserimpersonationattack.Furthermore,italsocannotprovideuseranonymity.Inthispaper,wecryptanalyzeLiuetal.’sschemeandproposeasecurityenhanceduserauthenticationschemetoovercometheaforementionedproblems.Especially,inordertopreservetheuseranonymityandpreventtheguessingattack,weusethedynamicidentitytechnique.Theanalysisshowsthattheproposedschemeismoresecureandefficientthanotherrelatedauthenticationschemes.
简介:Withouttheassumptionthattheprivatekeysarekeptsecureperfectly,cryptographicprimitivescannotbedeployedintheinsecureenvironmentswherethekeyleakageisinevitable.Inordertoreducethedamagecausedbythekeyexposureintheidentity-based(ID-based)signaturescenariosefficiently,weproposeanID-basedkey-insulatedsignatureschemeinthispaper,whicheliminatestheexpensivebilinearpairingoperations.Comparedwiththepreviouswork,ourschememinimizesthecomputationcostwithoutanyextracost.Underthediscretelogarithm(DL)assumption,asecurityproofofourschemeintherandomoraclemodelhasalsobeengiven.
简介:Intheair-waterquantumkeydistribution(QKD),theirregularseasurfacehassomeinfluenceonthephotonpolariza-tionstate.Thewindisconsideredasthemainfactorcausingtheirregularity,sothemodelofirregularseasurfacebasedonthewindspeedisadopted.Therelationshipsofthequantumbiterrorratewiththewindspeedandtheinitialincidentanglearesimulated.Therefore,themaximumsecuretransmissiondepthofQKDisconfirmed,andthelimita-tionofthewindspeedandtheinitialincidentangleisdetermined.Thesimulationresultsshowthatwhenthewindspeedandtheinitialincidentangleincrease,theperformanceofQKDwillfalldown.Undertheintercept-resendattackcondition,themaximumsafetransmissiondepthofQKDisupto105m.Torealizesafecommunicationsinthesafedivingdepthofsubmarines(100m),theinitialincidentangleisrequestedtobenotexceeding26~,andwiththeinitialincidentan~leincreased,thelimitationofwindspeedisdecreased.
简介:Withparametricdown-conversionsources(PDCSs),thenonorthogonaldecoystateprotocolbasedononevacuumandtwoweakdecoystatesispresented.ThedetectioneventsonBob'ssidearedividedintotwogroupsdependingonwhetherAlicegetsatriggerornot:triggeredcomponentsandnontriggeredcomponents.Thetriggeredcomponentsareusedtoestimatethefractionsanderrorratesofsingle-photonandtwo-photonpulses,andthenthefinalsecurekeyrateisdeduced.Besides,bothtriggeredandnontriggeredcomponentsareusedtodeduceamoreaccuratevalueofthekeygenerationrate.Thesimulationofthefinalkeygenerationrateovertransmissiondistanceshowsthatthefirstmethodcanobtainakeygenerationrateclosetothetheoreticallimitoftheinfinitedecoystateprotocol,whilethesecondmethodisbetter.
简介:一个光标签的标签扑灭比率和分散赔偿正在交换传播系统优化,它采用40-Gb/s回来到调音的零微分阶段移动(RZ-DPSK)用622-Mb/s振幅移动调音标记的收费载重(问)控制数据。在我们的计划,收费载重和标签的接收装置敏感分别地完成-27.8dBm和-33.5dBm。在在40km上播送了以后,60km和80km挑选模式纤维(SMF)(与分散赔偿)分别地,收费载重能没有力量惩罚被恢复,当标签能与不到2dB惩罚被恢复时。
简介:简要阐述了智慧城市建设模式差异,对智慧城市建设采用系统工程的理论和方法的重要性进行了讨论,然后提出智慧城市系统工程进行设计创新的几个问题。