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  • 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.

  • 标签: IRREGULAR sea surface quantum key distri-aution
  • 简介:AbstractIn order to effectively implement the Tianjin Biosecurity Guidelines for Codes of Conduct for Scientists, biosecurity awareness-raising and education are essential because if these are not in place scientists will not understand the need for biosecurity codes of conduct. In an effort to assist in the implementation of the guidelines, a small-scale survey was carried out in early 2022 of biosecurity awareness-raising and education projects that have been developed over the last two decades to discover what resources and experience have been accumulated. It is argued that the survey demonstrates that much of what is needed to implement the guidelines effectively has been developed, but that there are specific deficiencies that need to be remedied quickly. In particular, an updated teaching resource covering the core issues related to the Biological and Toxin Weapons Convention (BTWC) and the problem of dual use in scientific research needs to be made widely available and translated into at least the six official United Nations (UN) languages. Additionally, more specialists from the Humanities with expertise in ethics need to become involved in biosecurity awareness-raising and education activities. While advantage should be taken now of the available national, regional and international networks of people involved in related activities, it is suggested that in the longer term cooperation in biosecurity awareness-raising and education will benefit from the development of an equivalent organisation to the International Nuclear Security Education Network (INSEN) organised through the International Atomic Energy Agency (IAEA).

  • 标签: Tianjin Biosecurity Guidelines Biosecurity education Survey Biological and Toxin Weapons Convention (BTWC)
  • 简介:Researchonnewtypesofcastables,pre-castassemblypartsandthermalinsulationmaterialswithgoodresistancetowear,thermalshockanderosion,andlowthermalconductivity,wasdonetosolveproblemsofhighsystemenergyconsumption,crackingandspallingofpartialliningandmismatchoffurnacetopmaterialandhangingmaterialandsoon,causedbyunreasonabledesignofChina'sAl(OH)3dilutephasefluidizedbedroastingfurnacelining.Severaldifficultproblemssuchasthematchingofdifferentmaterials,preservationofexpansionjointsamongdifferentzonesandreasonablemechanicaldistributionofliningweresolved.'Integratedfurnace'conceptwasestablishedincludingrefractoriesR&D,liningstructuredesign,constructionoptimization,furnacewarmingtechnology,initialoperationandliningmaintenancetechnology.Thekeytechnologiesofhigh-efficiencyandenergy-savingforfurnacesweredeveloped.TheseachievementshavebeenappliedtoChina'sAl(OH)3dilutephasefluidizedbedroastingfurnacestoreduceenergyconsumptionby1000MJpertonalumina,enhancethecapacityandreducetheexhaustgasemission.

  • 标签: AL(OH)3 流化床 能源效率 稀相 烧烤炉 技术
  • 简介:DuringtheEighthFive-YearPlanperiod,ShaanxiProvinceintensifiedtherestructuringofinvestmentandmacro-controlinfixedassetsinvestmentbyimplementingthepolicyof"limitingtotalamount,readjustingstructure,rectifyingorderandimprovingefficiency".ThewholeprovincerealizedRMB110billioninfixedassetsinvestment,(includingRMB86.5billionbystate-ownedunits,RMB14.23billionthroughloansfromtheconstructionbank,makingup16.5percent),RMB67billionmorethanintheSeventhFive-YearPlanperiod,withanannualincreaseof26.5percent.Thankstothesupport,agroupofmedium-to-largeandkeyprojectshavebeenputinto

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  • 简介:SPSS13.0wasusedtoprocessthedataofthe1-6batchofkeyculturalrelicconservationunitspromulgatedbytheStateAdministrationofCulturalHeritageofChina;andmulti-elementevaluationmethodwasusedtocalculatethecompositedistributionindex.ThespatialdistributionofculturalrelicsofprovincesinChinacanbedividedintofourgrades,namely:veryrichareas,richareas,poorareasandverypoorareas;thearticleanalyzesthecharacteristicsofculturalresourcesinspatialandtemporaldistribution.Thepaperholdsthat(1)thedistributionofChina'sculturalrelictourismresourcesisrelativelyconcentrated,differentsharplyfromregiontoregion,withmoreHannation'sheritage,lessrelicsoftheethnicminorities;(2)Henan,Hebei,Shaanxi,ShanxiProvincearethemainregionswithheavydistributionofculturalresources;(3)relicsappearedinspecifictimeperiodsinChina'shistory.MingandQingDynasties,Sui,TangandFiveDynasties,Song,LiaoandJin,theWesternHan,ShangandZhoudynasties,theNewStoneAgearethemajorperiodsproducingmoreculturalrelics.Thispaperalsoanalyzesrelationshipsoftheemergenceofculturalrelicswithproductiontechnology,specifichistoricalprocess,specificgeographicallocation,politicalsystem,religion,nationalculture,customs,architecturalstylesandtechniquesofthetraditionalculturaleducationalsystem.Finally,thepaperdiscussesthedevelopmentandprotectionofheritage.

  • 标签: 国家文物局 中国文化 开发与保护 旅游资源 重点文物保护单位 特征
  • 简介:Bystudyingthetraditionalspectralreflectancereconstructionmethod,spectralreflectanceandtherelativespectralpowerdistributionofalightingsourcearesparselydecomposed,andtheorthogonalpropertyoftheprincipalcomponentorthogonalbasisisusedtoeliminatebasis;thenspectralreflectancedataareobtainedbysolvingasparsecoefficient.Aftertheoreticalanalysis,thespectralreflectancereconstructionbasedonsparsepriorknowledgeoftheprincipalcomponentorthogonalbasisbyasingle-pixeldetectoriscarriedoutbysoftwaresimulationandexperiment.Itcanreducethecomplexityandcostofthesystem,andhascertainsignificancefortheimprovementofmultispectralimageacquisitiontechnology.

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  • 简介:Withparametricdown-conversionsources(PDCSs),thenonorthogonaldecoystateprotocolbasedononevacuumandtwoweakdecoystatesispresented.ThedetectioneventsonBob'ssidearedividedintotwogroupsdependingonwhetherAlicegetsatriggerornot:triggeredcomponentsandnontriggeredcomponents.Thetriggeredcomponentsareusedtoestimatethefractionsanderrorratesofsingle-photonandtwo-photonpulses,andthenthefinalsecurekeyrateisdeduced.Besides,bothtriggeredandnontriggeredcomponentsareusedtodeduceamoreaccuratevalueofthekeygenerationrate.Thesimulationofthefinalkeygenerationrateovertransmissiondistanceshowsthatthefirstmethodcanobtainakeygenerationrateclosetothetheoreticallimitoftheinfinitedecoystateprotocol,whilethesecondmethodisbetter.

  • 标签: 量子密钥分发 参量下转换 非正交 诱骗 真空状态 安全密钥
  • 简介:随着多宗网络银行犯罪事件的发生,网上银行安全越来越被人重视,如何才能加强系统应用的安全性,提升人们对网上银行的信任度,成为网上银行业务中最亟待解决的问题,本文为读者带来指纹U-KEY,以供大家参考。

  • 标签: 身份认证系统 网络银行 指纹 网上银行业务 安全性 信任度
  • 简介:Background:Accelerometershavebeensuggestedtoprovideadditionalinformationduringthe6-minwalktestwhichmaybeusefulinevaluatingchangesinfunctionalexercisecapacity.TheaimofthestudywastoidentifywhethertheadditionalinformationmeasuredbytheMyWellnessKey~(TM)(MWK)accelerometerduringatreadmill6-minwalktest(t-6MWT)wasrelatedtocurrentlyusedoutcomemeasures.Methods:Fifteenparticipants(9males,6females)performedaself-pacedt-6MWT.RespiratorygasanalysisandwalkingdistanceweremeasuredwhilstwearingtheMWK.Results:Asignificantcorrelationwasestablishedbetweenactivitycountsand6-minwalkdistance(6MWD)(r=-0.847,p<0.001)yetnot6-minwalkwork(6MWW)(r=-0.337,p=0.220).EnergyexpenditureestimatedbytheMWKwasstronglycorrelatedto6MWW(r=0.938,p<0.001)butnot6MWD(r=0.477,p=0.072).TheMWKsignificantlyunderestimatedenergyexpenditure(36.73,CI=33.9-39.7kcal)comparedtogasanalysis(54.35,CI=46.2-61.4kcal)demonstratingpooragreementbetweenthetwoanalyses(Bias=-17.61kcal,Limitsofagreement=-37.4,t2.2kcal).Measurementoftimespentundertakinglight,moderate,andvigorousphysicalactivitywasnotsignificantlydifferent(p>0.05)betweentheMWKandgasanalysis.Conclusion:EstimatedenergyexpenditureprovidedbytheMWKwasstronglycorrelatedto6MWW;however,MWKunderestimatedenergyexpenditureasmeasuredbygasanalysis.TheMWKmayprovideoutcomedatathatsupplementthosecurrentlyprovidedbythe6MWDforfunctionalcapacityassessmentduringthet-6MWT.

  • 标签: 加速度计 跑步机 健康 试验 TM 气体分析
  • 简介:20世纪中国百年文学理论教材建设中普遍存在着文学本质主义的思想倾向。1960年代的文论教材做出了摆脱苏联模式的努力,1980、1990年代的文论教材以审美论、审美意识形态论置换意识形态论,但都并没有突破文学本质主义的思维模式和理论框架。新世纪以来的新锐文论教材打出了反本质主义的旗号,却没能找到反本质主义之后文论教材建设的康庄之路。以文学存在方式代替文学本质作为文学理论教材编写中的基本文学观念值得提倡。

  • 标签: 文学理论教材 本质主义 文学观念 文学存在方式
  • 简介:根据教育部的部署,2001年秋季,我国新一轮基础教育课程改革进入试点阶段,初中课标教材开始实验.教材作为学校课程最重要和最直接的育人载体,历来是课改的焦点问题之一.课程教材研究所中学数学课程教材研究开发中心(人民教育出版社中学数学室)以《全日制义务教育数学课程标准(实验稿)》(以下简称《标准》)为依据,

  • 标签: 课标教材 实验工作 初中数学 《全日制义务教育数学课程标准(实验稿)》 总结经验 巩固成果
  • 简介:摘要本文结合笔者的教学实践论述了如何在学生没有时间开展课外阅读的情况下,充分利用教材积累素材,并模仿教材写出好的作文。

  • 标签: 有效学习 积累素材 仿写
  • 简介:摘要:“文章不厌百回改”“文章是写出来的,更是改出来的”……对于这些关于习作修改的名言俗语,老师们如数家珍,学生也耳熟能详。但学生写完后,有几个能真正坐下来,用心修改呢?笔者曾多次询问学生,为什么写完作文后不认真修改。他们的回答大都一致:那是老师布置的作业啊!原来,在孩子们的心中,写作文,就是完成老师布置的任务,是“作业”,不是为了“自我表达和与人交流”。估计他们从没有想过,“写作是运用语言文字进行表达和交流的重要方式,是认识世界、认识自我、创造性表述的过程”。本文基于统编教材下如何用教材指导习作展开论述。

  • 标签: 统编教材 如何用教材 指导习作
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