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  • 简介:TheBaimazhainickeldeposit,YunnanProvince,China,islocatedinthesouthernpartoftheSanjiang(Tri-river)alkali-richintrusiverockbelt(SanjiangARIR).Inthispaperwasconducted40Ar-39Ardatingoftwophlogopitesinlamprophyreswhichare,asdikes,widelydistributedintheorefield,andtwoplateauageswereac-quired,i.e.,32.46±0.62Maand32.01±0.60Ma,respectively(averaging32.23±0.60Ma).Theagesareobviouslyyoungerthanthoseoftheore-hostedcomplexandmineralizationoftheBaimazhainickeldeposit.Incombinationwiththecharacteristics,itisindicatedthatlamprophyresintheorefieldandthoseintheSanjiangARIRaresimilarintectonicsetting,mineralassemblageandgeochemistry.Itisconsideredthatlamprophyresintheorefieldaretheim-portantcomponentoftheSanjiangARIR,andthelamprophyresandore-hostedcomplexintheorefieldrepresenttheproductsoftwotimesofdifferentmagmaticactivityfromdifferentmantlesources.Ontheotherhand,theageoflamprophyresintheorefieldisolderthanthatofthestrike-slipshearingoftheAilaoshan-Honghefaultbelt,sug-gestingthatthestrike-slipshearingoftheAilaoshan-Honghefaultbeltisnotthefactorleadingtomagmaticactivityoflamprophyresintheorefield,whileitismorepossiblethatmagmaticactivityoftheSanjiangARIRpromotedstrike-slipshearingofthefaultbelt.

  • 标签: 煌斑岩 年龄测定 地质学 镍沉淀 云南
  • 简介:“ThetravelsoftheCaesarsbringinmostaspectsofimperialhistory”.SuchwastheassertionofSymeinhissurveyoftheperipateticreignofHadrian(1988,159).AfterHadrian,thenextjourneyofrealsignificanceundertaknbyanemperorwasthatofLuciusVerus,whospentfiveyearsawayfromRomeascommanderofmilitarycampaignsintheeast.Thesetravels,likethoseofHadrian,

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  • 简介:活动特定的网络(MANET)是有能是的无线移动式节点的一种很复杂的分布式的通信系统自由地并且动态地self-organizedinto任意、暂时的网络拓扑。MANET继承无线网络的几限制,同时使从MANET的特性产生的新挑战例如线路失败,隐藏终端和暴露的终端。当TCP在MANET环境被使用时,问题不得不被处理的流氓的棕土。在这篇论文,这块动态地上的全面调查被给。明确地,第一次,损害TCP性能的所有因素基于网络协议分级被识别,即,在物理层的有损耗的无线隧道;在MAC层的过多的竞争和不公平的存取;在网络层,MAC层和网络层的脆弱的路由选择协议联系了移动式节点;在传送层和传送层的不适宜的拥挤窗口大小联系了不对称的路径。这些因素怎么降级TCPperformance清楚地被解释。基于怎么减轻每上面列出的这些因素的影响,然后,存在答案尽可能包括地被收集并且分类进很多个范畴,和他们的优点和限制被讨论。这些答案的基于的在限制,为设计更柔韧的答案的一套开的问题被建议。

  • 标签: 移动网络 MANETS TCP 路由失效 节点迁徙率
  • 简介:合作路由技术能高效地由创始地选择合作节点提交数据改进网络的性能。在这篇文章,合作路由算法基于三个不同criteria:optimal隧道状态,最大的留下精力,和最短的路径被建议并且实现。模拟基于网络模拟(NS)把建议算法的表演与non-cooperativedestination-sequenced距离作比较--向量(DSDV)协议。结果表明合作算法以牺牲可接受的规范的网络负担的成本与特殊获得超过DSDV路由协议。

  • 标签: 路由算法 路由协议 移动通信网络 信道优化
  • 简介:Inmobileadhocnetworks(MANET),nodesmovefreelyandthedistributionofaccessrequestschangesdynamically.Replicaallocationinsuchadynamicenvironmentisasignificantchallenge.Inthispaoer,adynamicadaptivereplicaallocationalgorithmthatcanadapttothenodesmotionisproposedtominimizethecommunicationcostofobjectaccess.Whenchangesoccurintheaccessrequestsoftheobjectorthenetworktopology,eachreplicanodecollectsaccessrequestsfromitsneighborsandmakesdecisionslocallytoexpandreplicatoneighborsortorelinquishthereplica.Thealgorithmdynamicallyadaptsthereplicaallocationschemetoalocaloptimalone.SimulationresultsshowthatouralgorithmsefficientlyreducethecommunicationcostofobjectaccessinMANETenvironment.

  • 标签: 移动ADHOC网络 MANET 自适应分配算法 读写模型 稳定邻近值