简介：Twosignaturesystemsbasedonsmartcardsandfingerprintfeaturesareproposed.Inonesignaturesystem,thecryptographickeyisstoredinthesmartcardandisonlyaccessiblewhenthesigner'sextractedfingerprintfeaturesmatchhisstoredtemplate.Toresistbeingtamperedonpublicchannel,theuser'smessageandthesignedmessageareencryptedbythesigner'spublickeyandtheuser'spublickey,respectively.Intheothersignaturesystem,thekeysaregeneratedbycombiningthesigner'sfingerprintfeatures,checkbits,andarememberablekey,andtherearenomatchingprocessandkeysstoredonthesmartcard.Additionally,thereisgenerallymorethanonepublickeyinthissystem,thatis,thereexistsomepseudopublickeysexceptarealone.

简介：Duringthelastfewdecades,photothermalradiometry(PTR)hasbeengreatlydevelopedandwidelyappliedinthefieldofnondestructivetesting.However,thetraditionalPTRsystememploysanexpensivelock-inamplifiertodetecttheweakphotothermalsignal,whichleadstohighcostandlongtesttime.Inthispaper,afasttransmissionPTRsystembasedonsamplingbyusinganinternalcomputersoundcardwasdevelopedtolowerthesystemcostandshorterthetesttime.Apieceofamorphoussilicon(a:Si)thinfilmsolarcellswithartificialdefectswaspreparedandtestedbythesystem.Theresultsshowthatthesharpeneddefectscanbeidentifiedeasilyandquicklyaccordingtothesignificantpeaksoftheoriginalinfraredsignalsampledbytheinternalcomputersoundcard.Furthermore,moredetaileddefectscanbeinvestigatedbyprocessingtheinfraredsignal.ThesevalidatetheeffectivenessoftheproposedtransmissionPTRsystemasalowcostandefficientnon-destructivetesttechnique.

简介：Nowadays,thepassword-basedremoteuserauthenticationmechanismusingsmartcardisoneofthesimplestandconvenientauthenticationwaystoensuresecurecommunicationsoverthepublicnetworkenvironments.Recently,Liuetal.proposedanefficientandsecuresmartcardbasedpasswordauthenticationscheme.However,wefindthatLiuetal.’sschemeisvulnerabletotheoff-linepasswordguessingattackanduserimpersonationattack.Furthermore,italsocannotprovideuseranonymity.Inthispaper,wecryptanalyzeLiuetal.’sschemeandproposeasecurityenhanceduserauthenticationschemetoovercometheaforementionedproblems.Especially,inordertopreservetheuseranonymityandpreventtheguessingattack,weusethedynamicidentitytechnique.Theanalysisshowsthattheproposedschemeismoresecureandefficientthanotherrelatedauthenticationschemes.

简介：In2010,Hwang,etal.proposeda'DoS-resistantID-basedpasswordauthenticationschemeusingsmartcards'asanimprovementofKim-Lee-Yoo's'ID-basedpasswordauthenticationscheme'.Inthispaper,wecryptanalyzeHwang,etal.'sschemeandpointoutthattherevealedsessionkeycouldthreatthesecurityofthescheme.Wedemonstratethatextractinginformationfromsmartcardsisequaltoknowingthesessionkey.Thusknownsessionkeyattacksarealsoeffectiveundertheas-sumptionthattheadversarycouldobtaintheinformationstoredinthesmartcards.WeproposedanimprovedschemewithsecurityanalysistoremedytheweaknessesofHwang,etal.'sscheme.Thenewschemedoesnotonlykeepallthemeritsoftheoriginal,butalsoprovidesseveraladditionalphasestoimprovetheflexibility.Finally,theimprovedschemeismoresecure,efficient,practical,andconvenient,becauseellipticcurvecryptosystemisintroduced,theexpensivesmartcardsandsynchronizedclocksystemarereplacedbymobiledevicesandnonces.