简介:Thestudyofcycliccodesoverringshasgeneratedalotofpublicinterest.Inthispaper,westudycycliccodesandtheirdualcodesovertheringZP2oflengthpe,andfindasetofgeneratorsforthesecodes.Theranksandminimalgeneratorsetsofthesecodesarestudiedaswell,whichplayanimportantroleindecodinganddeterminingthedistancedistributionofcodes.
简介:分析了视频字符叠加系统在电磁干扰严重时会出现视频叠加的字符信息丢失和不响应字符叠加命令的原因。给出了相同硬件电路情况下,利用SST89E58RD2的内部模块来解决单片机程序跑飞和字符叠加芯片复位所造成的叠加字符丢失和程序跑飞问题的实现方法。
简介:AlinearizationattackontheKeyStreamGenerator(KSG)ofthemodifiedE0algorithmproposedbyHermelin[ProceedingsofICISC'99,SpringerLNCS1787,2000,17-29]isgiveninthispaper.TheinitialvaluecanberecoveredbyalinearizationattackwithO(260.52)operationsbysolvingaSystemofLinearEquations(SLE)withatmost220.538unknowns.FrederikArmknecht[CryptologyePrintArchive,2002/191]proposedalinearizationattackontheKSGofE0algorithmwith0(270.341)operationsbysolvinganSLEwithatmost224.056unknowns,sothemodificationproposedbyHermelinreducestheabilityofE0toresistthelinearizationattackbycomparingwiththeresultsofFrederikAnnknecht.
简介:Atomicityisnecessaryforreliableandsecureelectroniccommercetransactionandtoguaranteetheparticipants'interests.Anatomicandefficiente-cash(electroniccash)transactionprotocolbasedontheclassicale-cashschemeispresented.Thedeliveryofdigitalgoodsisincorporatedintotheprocessofpaymentintheprotocol.Apartfromensuringallthreelevelsofatomicity,thenovelprotocolfeatureshighefficiencyandpracticabilitywithunfavorablestrongassumptionremoved.Furthermore,theproposedprotocolprovidesnon-repudiationproofsforanyfuturedisputes.Atlast,analysisoftheatomicityandefficiencyisillustrated.