简介:这份报纸在使隧道褪色的伪静电干扰rayleigh上为合作传播基于空间调整论述一个新奇增长中继协议,也就是空间的调整增长中继(SMIR),它使用空间调整的概念进增长中继。在建议协议,信息位被印射进带单位的二个信息:1)在星座图的一个星座点并且2)空间领域,即进一个特别合作用户数字的地点。为SMIR协议的框架错误率(FER)的分析表示被导出。模拟结果证实介绍数学分析并且证明那个SMIR协议分别地为3-bit/symbol和5-bit/symbol传播在常规协议上在信号获得2和3dB到噪音比率(SNR)。而且,在这个协议下面,系统能完成高得多的产量,它意味着我们的建议协议在性能带重要获得。
简介:Coverageholesoftenappearinwirelesssensornetworksduetosensorfailureortheinheritanceofsensor'srandomdistribution.Inthehybridmodel,mobilesensorsinthenetworkareacquiredtohealcoverageholesbytheirmobility.Whenmultiplecoverageholesappearinthesensornetworkandeachofthemhasatimerequirement(inwhichthecoverageholehastobehealed),conflictsfortherequestsofthesamemobilesensormayarise.Adistributedmultiplemobilesensorschedulingprotocol(DMS)isproposedinthispapertosolvethisproblembyfindingmobilesensorsinthetimeresponsezonedefinedbythetimerequirementofeachcoveragehole.SimulationresultsshowthatDMScanwellschedulethemobilesensorstomovetomultiplecoverageholeswithinthetimerequirement.
简介:Thewirelessapplicationprotocol(WAP)protocolisnowtheleadingstandardforinformationservicesonwirelessterminalslikedigitalmobilephones.BytheuseofWAP,wirelessdevices,likemobilephones,arepossiblyinfectedwithvirusandworms.Thoughuptonowthereisnosuchattack,astheusageofscriptlanguagesincreases,thereisachanceofmaliciouscodeinjection.ThispaperdiscussesthethreatswithcurrentWAPprotocol,andhowchangesintheprotocolandtheincreaseinitsusagewillenableentryofrealviruses.Futurethreatscenariosarepresentedalongwithsuggestionstoavoidtheseproblems.
简介:Theproceduresofultrasonicextractionandclean-upwereoptimizedforthedeterminationofpolycyclicaromatichydrocarbons(PAHs)inmarinesediments.Sampleswereultrasonicallyextracted,andtheextractswerepurifiedwithaminiaturizedsilicagelchromatographiccolumnandanalyzedwithhighperformanceliquidchromatography(HPLC)withafluorescencedetector.Ultrasonicationwithmethanol-dichloromethane(2:1,v/v)mixturegavehigherextractionefficiencythanthatwithdichloromethane.Amongthethreeelutionsolventsusedinclean-upstep,dichloromethane-hexane(2:3,v/v)mixturewasthemostsatisfactory.Undertheoptimizedconditions,therecoveriesintherangeof54.82%to94.70%withRSDsof3.02%to23.22%foraspikedblank,andintherangeof61.20%to127.08%withRSDsof7.61%to26.93%foraspikedmatrix,wereobtainedforthe15PAHsstudied,whiletherecoveriesforaNISTstandardreferenceSRM1941bwereintherangeof50.79%to83.78%withRSDsof5.24%to21.38%.Thedetectionlimitswerebetween0.75ngL-1and10.99ngL-1fordifferentPAHs.AsamplefromtheJiaozhouBayareawasexaminedtotesttheestablishedmethods.