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500 个结果
  • 简介:Digitalsignatureisoneofthemostimportantcryptographicprimitives.WeproposedanewdigitalsignatureschemebasedonCatalano’strapdoor.SinceCatalano’strapdoorismoreefficientthanexistingtrapdoorsinnumbertheory,ourschemeneednotmodularexponentiationbutseveralmodularmultiplicationsinthesigningalgorithm.Wealsoprovedourschemeisprovablysecureagainstadap-tivelychosenmessageattackbyusingtheForkinglemma.

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  • 简介:CRTCornercuttingtubeisconsideredasadefinitiverejectandwillbesenttoreclaimatalltimes.Itcausedlotsofmaterialloss.Inthispaper,anoveltechnologyusedtosaveCRTscornercuttingtubeispresentedfirstly.AsetofrepairsystemhasbeensuccessfullydevelopedtorepairCRTscornercuttingtube.Then,theprocesstechnologyforcornercuttingrepairhasbeenexcogitatedbyempiricalstudies.Finally,thecorrelativeperformancesofrepairedtubeareevaluated.Theexperimentalresultsshowthatthequalityofrepairedtubehasnodifferencewiththatofnormalproduct.Therepairyieldhasreachedabove97percent.Thisnewtechnologyhascontributedtoimprovingtheproductionyield,reducingthematerialconsumptionanddecreasingthecostofcolorCRTproduction.

  • 标签: CRT 阴极射线管 显示器 修正系统
  • 简介:Thisletterintroducesthedesignideas,simulationandtestresultsofanS-bandklystronwithbandwidthof11%,whichwasdevelopedbytheInstituteofElectronics,ChineseAcademyofSciences(IECAS).Onthepeakpowerlevelof800kW,theefficiencyofklystronismorethan30%;thegainismorethan41dB;theequal-drivingrelativeinstantaneousbandwidthisover11%;theaveragepowerislargerthan8kW,andthepowerfluctuationwithinbandwidthislessthan1.5dB.

  • 标签: S波段速调管 频宽 峰值功率 IECAS
  • 简介:2004年12月28日,广西民族印刷厂举办了德国高宝(KBA)利必达105HS-5对开五色胶印机的投产庆典,出席此次活动的有广西新闻出版局的领导,广西财政厅的领导,广西出版总社的领导以及广西各个出版社和著名的广告公司相关人员约400人。

  • 标签: 广西财政厅 领导 广告公司 印刷厂 投产 人员
  • 简介:Inthelaserwarningsystem,anon-mechanicalscanningFabry-Perot(F-P)typelaserwarningmethodanditscrucialcomponent-laserincidentsensordesignmethodarebroughtout,andtheF-Petalonwiththeinterferometricfiltercombinationisadopted.Fortheincidentlaserpulsewithacertainwavelength,thetransmittancedifferenceoftheinterferometricfiltersisindependentwithpolarizationofincidentlight,anddescendsalmostlinearlyastheincidentanglegetswider.Alaserincidentanglesensorexperimentalplatformisbuiltup,andtheexperimentiscarriedoutwithagivenlaserrangefinder.Astheresultsindicate,whentheincidentangleislessthan5o,thetransmittancedifferencemeasuredbythelaseranglesensorissignificantlylower,andthedeviationismorethan10%.Whiletheincidentangleisgreaterthan10o,thedeviationisreducedsignificantly.

  • 标签: 激光扫描 预警方法 设计方法 计划生育 机械式 角度传感器
  • 简介:介绍了TI公司数字信号处理器TMS320F2812的引导方式、Flash编程方法、Flash启动流程。在此基础上提出了一种基于CAN总线的TMS320F2812程序的远程加载方案,并详细阐述了详细的实现过程。该方案摆脱了Flash编程时对JTAG接口、RS232接口的依赖,非常适用于军用领域,具有较大的实用价值。

  • 标签: F2812 CAN总线 远程更新 FLASH编程
  • 简介:ThecharacteristicofEDFAinWDMsystemisanalyzed.ThesimulationsystembasedonthearchitectureoftheChinaInformationNetwork(CAINONET)isintroduced,andtheinfluenceofnoisefigure,gainunflatnessandoutputpowerofEDFAontheBERperformanceandscaleofnetworkisinvestigated.Moreover,theinfluenceofnoisefigureisstudiedwithdifferentcrosstalk.Meanwhile,itisindicatedthatitisimportanttoapplythe"nodeisolationprinciple"intheopticalnetwork.Theresearchresultscanprovidethevaluablereferenceforthepracticalconstructionofallopticalnetwork.

  • 标签: 波分复用 光纤通信 中国 信息网络 光交叉连接
  • 简介:本文叙述由电流互感器、PIC单片、运算放大器等组成的智能漏电流保护器及其硬软件设计。智能漏电流保护器具有大漏电流和小漏电流控制,实现报警与保护作用,并具有缺相保护功能。

  • 标签: 电流互感器 PIC单片机 漏电流保护器
  • 简介:ThislettergivesarandomconstructionforLowDensityParityCheck(LDPC)codes,whichusesaniterativealgorithmtoavoidshortcyclesintheTannergraph.TheconstructionmethodhasgreatflexiblechoiceinLDPCcode'sparametersincludingcodelength,coderate,theleastgirthofthegraph,theweightofcolumnandrowintheparitycheckmatrix.ThemethodcanbeappliedtotheirregularLDPCcodesandstrictregularLDPCcodes.Systemiccodeshavemanyapplicationsindigitalcommunication,sothisletterproposesaconstructionofthegeneratormatrixofsystemicLDPCcodesfromtheparitycheckmatrix.Simulationsshowthatthemethodperformswellwithiterativedecoding.

  • 标签: 低密度奇偶校验码 LDPC 随机结构 SPA算法 奇偶校验矩阵
  • 简介:介绍了S波段极低噪声超导滤波放大组件的设计过程,采用了低温仿真建模和拓扑结构优化设计关键技术。该组件将用于接收系统中的的低温接收前端,能提高雷达的灵敏度和有效作用距离。该组件由超导滤波器和低温放大器组成,具有体积小、重量轻、可靠性高等特点。

  • 标签: 噪声温度 低温放大器 超导滤波器
  • 简介:在有低极化模式的40个Gb/s系统分散(PMD)纤维,一阶的PMD是有相当小的价值的dominate因素。由一个电的极化控制器(PC)组成的一个适应PMD赔偿者,维持纤维(PMF)的极化的节,极化(DOP)的度察觉者和一个反馈控制模块40Gb/sNSFCNet被采用。这个赔偿者有简单结构和高速度,它能适应地补偿一阶的PMD直到20ps,平均寻找时间是2ms。CLC数字TN929.11

  • 标签: 自适应PMD补偿器 补偿实验 CSRZ系统 一阶PMD 光纤 极化
  • 简介:S模式ADS-B系统概念结合了自动相关监视和S模式信标雷达,是一种监视和数据链的综合系统,包括机载设备和地面设备,它是S模式二次监视雷达的基础上发展起来的一种新型的空管监视系统,正逐步得到国际上的广泛应用。介绍了S模式ADS-B的原理及应用范围,并对其性能进行了详细的对比分析。

  • 标签: ADS-B S模式 二次雷达 断续振荡器 新航行系统
  • 简介:Transmissionperformanceofelectroabsorptionmodulatorin10Gb/stransmissionsystemshasbeensimulatedandanalyzedundertheconditionoftakingintoaccountthechirp,extinctionratio,transmissivityandrise/falltime.ResultsshowthatshorttransmissiondistancewithoutEDFAafterEAMcanbeusedinfuturemetropolitanareanetwork,butthetransmissivitymustbecarefullyconsidered.Thesamplingtimerangeanddecisionlevelcanbeoptimizedtoreducethebiterrorratio.

  • 标签: 电吸收调制器 透射率 决策水平 取样 短距离传输系统
  • 简介:ItiswellknownthatthealgebraicexpressionofASSS-boxisverysimpleandonly9termsareinvolved.Hence,AESsecurityissuspectedalthoughthereisnovulnerabilityonitsofar.ToeliminatetheweaknessofextremelysmalltermsinthealgebraicexpressionofAESS-box,oneimprovedAESS-boxisproposed,whichpreservesthealgebraicdegreeinvariablebutsignificantlyincreasesthenumberofitsalgebraicexpressiontermsfrom9to255.Atthesametime,Booleanfunctionhasgoodcharactersinbalanceandstrictavalanchecriterion(SAC),etc.Finally,itisprovedthattheimprovedAESS-boxschemeissecuregainstthepowerfulknowndifferentialandlinearcryptanalysis.

  • 标签: 线性密码分析 复杂性 AES 高级保密标准 美国国家标准所 S-BOX