简介：Acoupledmodel,whichisemployedtostudythedominatingfactorandkeyareaofElNinocycleformation,consistsofadynamicaloceanmodelandastatisticalatmosphericmodel.ThecoupledmodelwithseasonalforcingsuccessfullyreproducestheElNinoeventcyclewhichexhibitsquasi-regularoscillationswithapreferredperiodofabout4years.Theresultsshowthattheheatcontent(HC)istransportedbetweentheeasternandthewesterntropicalPacificareas.ThespatialdistributionofHCanomaliesforfourphasesofthewholecycleclearlyshowsapossibleformationmechanismofElNino.ExperimentsfurthersuggestthatseasurfacetemperatureinthetropicalPacificandHCinthecentraltropicalPacificarethemostimportantfactorsandthecentraltropicalPacificisthemostimportantareafordeterminingformationofElNinocycle.

简介：LongbeforethediscoveryofHelicobacterpylori,thereweremanyexcellentobservationalstudiesthatdocumenteddifferencesinthepatternsofgastroduodenaldisease.Itwasclearthatinthedevelopingworld,gastriculcerandgastriccancerweremorecommonthaninthedevelopedworldwhereduodenalulcerpredominated.Thiscorrelatedwiththedistributionofgastritisinduodenalulcerpatientswheretheinflammationwasantralpredominantwhileingastriculcerpatientsthegastritiswasmoreevenlydistributedthroughthestomach.Gastriculcersusuallyappearedinafairlyrestricteddistributioninthestomachneartheangulusandclosetothetransitionalzonebetweenantrumandbodymucosa.Asasocietydevelopedsothesepatternsofdiseasechanged.

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简介：Anumericalsimulationisperformedtofindoutakeyvorticalstructureinthelaminar-turbulenttransition.Alow-speedstreakisgeneratedinsidealaminarboundarylayerusinganisolatedcuboidroughness,aimedatprovidinganenvironmentunstabletoouterdisturbances.Then,ashortdurationjetisissuedintotheboundarylayer.Whenthejetvelocityislow,somevorticesappearintheboundarylayer,butthetransitionoftheboundarylayerdoesnottakeplace.However,whenthejetvelocityexceedsacertainthreshold,twovorticesnewlyappearabovetheelongatedlegsofaV-shapedvortexandonlyoneofthemisstretchedandsurvives.Afterthat,vorticesaregeneratedoneafteranotheraroundthesurvivedone.Bycomparingthedecayedandthesurvivedvortices,itisfoundthatthedifferenceintheirheightsisthekeycharacteristicwhichleadstothetransition.

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简介：　　Inordertoactivelyutilizethenon-traditionalresourcesandreducethedependenceofchemicalindustryoncrudeoil,theMinistryofScienceandTechnologyhasincludedtheproject"Keytechnologyformanufactureofmassivechemicalsviaanon-oilbasedroute"inthe"NationalEleventhFive-YearScienceandTechnologySupportingPlan"andisnowcallingforapplicationforrelevantresearchprojects.……

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

简介：本文以国家林业局重点科技项目的研究成果为例,介绍以USBKey认证的方式实现数字文献资源统一安全访问的方法。

简介：在最近的年里，电子learning系统在许多公司作为一个训练工具被采用了，当它能帮助雇员到在一短时间并且以低成本的完全的训练。在这上下文以内，自从2003，在台湾的经济事情(MOEA)的部的工业开发局(IDB)每年赞助了超过50家企业帮助他们实现设定的电子learning系统。关于电子learning的过去的研究主要集中了于一个标准并且采用了回归途径，例如检验在满足或继续的用法意愿和各种各样的先前的因素之间的关系。尽管回归方法能揭开电子learning采纳的重要因素，他们不能显示出每个因素的罐头(weighting)，并且因此，公司不能分配资源的最佳的层次。克服这个问题，这研究收集了与从文学和专家意见的评论实现设定的电子learning系统的公司有关的因素，然后构造了一张层次因素桌子。基于因素的适当和独立，并且是由IDB，电子learning方案供应商和IDB的工程领导人的工程提升办公室的专家估计了赞助企业，这篇论文然后设计了一个分析层次过程(AHP)格式问询表并且送了它给这些一样的专家收集他们的回答。因素weightings基于模糊分析层次过程(FAHP)方法被导出。最后，关键因素的分析被执行，建议提供了。基于这个工作的结果，有有限资源的服务工业公司能完成合适的资源分配并且更快速并且成功地采用设定的电子Learning系统。

简介：PF_KEY协议是IPSec的重要组成部分。密钥管理进程利用PF_KEY与内核的SADB进行通信，实现SA(SecurityAssociation,安全联盟)和SP(SecurityPolicy，安全策略)的管理。本文将从PF_KEY协议构造和PF_KEy相关系统调用等方面描述OpenBSD内核中的PF_KEY实现。

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简介：Likeothercountriesintheworld,itisinevitabletoencoun-terwithsomeenvironmentproblemsintheprocessofen-ergydevelopmentandutilization.ItisespeciallysoinChinawhereenergystructureismainlybasedoncoal.Atpresent,coaltakes74%ofthetotalprimaryenergywhileoutofthe74%,only23%hasbeenconvertedintocleanandconvenientelectncenergy.Sopredomi-nately,theairpollutioninChinaismainlycausedbycoalsmoke.Inlargecities,theairpollutionbydirectcoalburningisbecomingmoreandmoreoutstandingduetothefastdevelopmentofindustryand

简介：Thisarticleistrytoexplainoranalyzethekeytechnologiesofcontrollingthesurfacequalityoflowcarbonsteelascaststripthroughinvestigationofinterfaceheattransferbetweensolidifiedshellandliquidsteel.Theoneofthekeytechnologiesofcontrollingsurfacequalityoflowcarbonsteelascaststripisthroughthecastingrollsurfacetextureinordertoachievethehomogeneoussolidificationonthecastingroll.Anotheristhroughformingathinfilmonthecastingrollsurfaceinordertoachieveabalancebetweenrapidsolidificationandhomogeneoussolidification.Thisfilmformedbetweenthetwinrollandthemoltensteelcanbecontrolledbyadjustingthechemicalcompositionandinclusioninliquidsteelthroughcontrollingtheamountofall[O]andfree[O].

简介：在全球海洋的由空至海的相互作用的七个关键区域被每月吝啬的海面的全球数据的综合分析决定温度(SST)，地面风，温度，湿度，海面可感热和潜伏的热流动。在在每个关键区域的SST和各大气的元素之间的时间落后关联焦点地被分析在不同关键区域暴露一样和由空至海的相互作用的不同特征。由空至海的热相互作用在每个区域，SST，温度和湿度是强壮的结果表演能相当被对方代替，特别地在中央东方太平洋和南方印度海洋。SST上的动态效果在不同区域是不同的，在中央西方的太平洋，如此的效果是更重要的。在可感热，潜伏的热和SST之间的关联在东方太平洋，西方的太平洋和二个主要季风区域是更重要的-西北的太平洋和南方印度海洋。由在每个关键区域分析SST和每个大气的元素的持续关联概率，我们进一步知道元素的异例，在哪个区域并且在时期很好在哪个被支撑或容易破坏了。这不仅对预言，而且到由空至海的相互作用的物理机制的讨论有益。

简介：Chinaisanimportantcountryinironandsteelindustry.Powerelectronicsconvertersarewidelyused.Forthecoldrollingmillsofhighspeed,AC-DC-ACconvertersshouldbeused.Inthepaper,thedesignandthecontrolsystemofthelargepowerthree-levelAC-DC-ACconverterwithIGCTsisinvestigated,andaback-to-backlargepowerthree-levelAC-DC-ACconverterwithIGCTshasbeengot.Withaseriesexperiments,theperformanceoftheconverterisexamined.Theexperimentresultindicatestheconverterreachesthedesignrequirementanditshowsexcellentperformance.Theconvertersystemhasbeenputintousesafely.ItisestimatedthattheAC-DC-ACconvertersystemwillbeusedinthedrivesystemsforrollingmillsinthenearfuture.

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简介：Withouttheassumptionthattheprivatekeysarekeptsecureperfectly,cryptographicprimitivescannotbedeployedintheinsecureenvironmentswherethekeyleakageisinevitable.Inordertoreducethedamagecausedbythekeyexposureintheidentity-based(ID-based)signaturescenariosefficiently,weproposeanID-basedkey-insulatedsignatureschemeinthispaper,whicheliminatestheexpensivebilinearpairingoperations.Comparedwiththepreviouswork,ourschememinimizesthecomputationcostwithoutanyextracost.Underthediscretelogarithm(DL)assumption,asecurityproofofourschemeintherandomoraclemodelhasalsobeengiven.

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