学科分类
/ 11
213 个结果
  • 简介:有生气的层的想法的为无线传感器的存取控制(MAC)协议联网的媒介(WSN)的设计吸引越来越多的注意。人们能由关于网络层和物理层获得某些信息改进MAC协议。这篇文章综合并且优化存在的某些跨层的协议。根据路由,在网络层的拓扑学信息,和在物理层的传播力量信息,时间槽任务算法在MAC层被改进了。由使用地理适应忠实算法(GAF)划分格子,传播电源控制并且为传感器节点安排工作/睡觉责任周期,一个新MAC协议被建议了到减少精力消费并且扩大WSN的一生。模拟结果证明MAC协议工作很好。

  • 标签: 无线传感器网络 能源控制 时分复用 MAC协议 GAF
  • 简介:Thewirelesssensornetwork(WSN)consistsofsensornodesthatinteractwitheachothertocollectivelymonitorenvironmentalorphysicalconditionsatdifferentlocationsfortheintendedusers.Oneofitspotentialdeploymentsisintheformofsmarthomeandambientassistedliving(SHAAL)tomeasurepatientsorelderlyphysiologicalsignals,controlhomeappliances,andmonitorhome.ThispaperfocusesonthedevelopmentofawirelesssensornodeplatformforSHAALapplicationoverWSNwhichcomplieswiththeIEEE802.15.4standardandoperatesin2.4GHzISM(industrial,scientific,andmedical)band.TheinitialstageofSHAALapplicationdevelopmentisthedesignofthewirelesssensornodenamedTelGmote.ThemainfeaturesofTelGmotecontributingtothegreencommunicationsincludelowpowerconsumption,wearable,flexible,user-friendly,andsmallsizes.Itisthenembeddedwithaself-builtoperatingsystemnamedWiseOStosupportcustomizedoperation.Thenodecanachieveapacketreceptionrate(PRR)above80%foradistanceofupto8m.ThedesignedTelGmoteisalsocomparablewiththeexistingwirelesssensornodesavailableinthemarket.

  • 标签: 无线传感器网络 传感器节点 家居环境 智能家居 电报 生活
  • 简介:基于结构化的内核主管部件,分析(KPCA)为非线性的进程被建议的一个新传感器差错诊断方法。由在变量的子集上执行KPCA,一套结构化的剩余,即,KPCA的放大力量,能以象部分PCA的一样的方法被获得。结构化的剩余在为传感器差错诊断填写一个隔离计划被利用,根据一个适当地设计的发生矩阵。传感器差错敏感和批评敏感被定义,基于哪个一个发生矩阵优化算法被建议改进结构化的KPCA的表演。建议方法的有效性在模仿的连续搅动的坦克反应堆(CSTR)上被表明过程。

  • 标签: 传感器故障 核主成分分析 故障诊断系统 非线性过程 基础 连续搅拌反应釜
  • 简介:Tofindtheoptimalroutingisalwaysanimportanttopicinwirelesssensornetworks(WSNs).ConsideringaWSNwherethenodeshavelimitedenergy,weproposeanovelEnergy*Delaymodelbasedonantalgorithms('E&DANTS'forshort)tominimizethetimedelayintransferringafixednumberofdatapacketsinanenergy-constrainedmannerinoneround.Ourgoalisnotonlytomaximizethelifetimeofthenetworkbutalsotoprovidereal-timedatatransmissionservices.However,becauseofthetradeoffofenergyanddelayinwirelessnetworksystems,thereinforcementlearning(RL)algorithmisintroducedtotrainthemodel.Inthissurvey,theparadigmofE&DANTSisexplicatedandcomparedtootherant-basedroutingalgorithmslikeAntNetandAntChainabouttheissuesofroutinginformation,routingoverheadandadaptation.SimulationresultsshowthatourmethodperformsaboutseventimesbetterthanAntNetandalsooutperformsAntChainbymorethan150%intermsofenergycostanddelayperround.

  • 标签: 计算机网络 信息素 能量消耗 无线电
  • 简介:为紧张和温度测量的一个光纤维传感器与纤维基于长时期纤维栅栏(LPFG)串联了布拉格栅栏(FBG)结构理论上并且试验性地被建议了并且认识到。有类似的敏感的二微观结构不能被用于的理论分析表演加倍参数测量。LPFG是由CO2激光的micromachined,并且FBG是由excimer激光的micromachined。为确认和比较,二FBG和一LPFG与三条传播山谷被串联,也就是在1536.3nm,在1551.2nm的LPFG山谷,和在1577.3nm的FBG2山谷的FBG1山谷。建议传感器的温度和紧张特征在4570椠歮愠獢牯敢獲愠敲映物瑳祬搠瑥牥業敮?桴潲杵?桰瑯慯潣獵楴?湡?灳'虪沟茲滀髷疇罐鏇V畳敲敭瑮?瑡琠敨猠浡?被测量硥楣慴楴湯?桷捩?敤潭獮牴瑡獥琠敨映慥楳楢楬祴漠?桴獩洠瑥潨d

  • 标签: 长周期光纤光栅 光纤传感器 参数测量 光纤布拉格光栅 准分子激光 灵敏度矩阵
  • 简介:Modifiedsensingmembranesbasedonfluorescencequenchingwerepreparedbythesol-gelmeth-od,usingformamideasthedryingcontrolchemicaladditive,tetraethoxysilaneasthemainmaterial,Ru(phen)3Cl2astheindicator.Themembranewiththeoptimumthicknessof20-50μmisuniformandcrack-free,inwhichtheindicatorhasaverysmallleakingrate.Themembraneisimmersedinwaterfor50h,themembranesensingparameterMdecreasesbylessthan5%.Thefiberopticoxygensensorwiththesensingmembranehasadetectionlimitof5×10-6M(ppm),aresponsetimeoflessthan30s,excellentreproducibilityandstability.

  • 标签: 溶胶-凝胶传感膜 纤维光学氧气传感器 制备方法 甲酰胺
  • 简介:Duetothelargescaleandcomplexityofcivilinfrastructures,structuralhealthmonitoringtypicallyrequiresasubstantialnumberofsensors,whichconsequentlygeneratehugevolumesofsensordata.Innovativesensordatacompressiontechniquesarehighlydesiredtofacilitateefficientdatastorageandremoteretrievalofsensordata.ThispaperpresentsavibrationsensordatacompressionalgorithmbasedontheDifferentialPulseCodeModulation(DPCM)methodandtheconsiderationofeffectsofsignaldistortionduetolossydatacompressiononstructuralsystemidentification.TheDPCMsystemconcernedconsistsoftwoprimarycomponents:linearpredictorandquantizer.FortheDPCMsystemconsideredinthisstudy,theLeastSquaremethodisusedtoderivethelinearpredictorcoefficientsandJayantquantizerisusedforscalarquantization.A5-DOFmodelstructureisusedastheprototypestructureinnumericalstudy.NumericalsimulationwascarriedouttostudytheperformanceoftheproposedDPCM-baseddatacompressionalgorithmaswellasitseffectontheaccuracyofstructuralidentificationincludingmodalparametersandsecondorderstructuralparameterssuchasstiffnessanddampingcoefficients.ItisfoundthattheDPCM-basedsensordatacompressionmethodiscapableofreducingtherawsensordatasizetoasignificantextentwhilehavingaminoreffectonthemodalparametersaswellassecondorderstructuralparametersidentifiedfromreconstructedsensordata.

  • 标签: 传感器 DPCM 工程振动 技术参数
  • 简介:即时监视传感器的运作的状态并且差错的精确诊断是必要的。这份报纸为传感器建议一个改进差错诊断计划,它包括差错察觉和差错鉴定。第一,趋势分析与最少的广场结合了支持向量机器(TA-LSSVM)方法被建议并且实现了检测差错。第二,改正产量代码支持向量机器(ECOC-SVM)的一个改进错误基于差错鉴定方法被建议区分不同传感器失败模式。表明建议计划的有效性,实验与一个MTi系列传感器,和比较与另外的差错鉴定方法被做的一些被进行。试验性的结果证明建议差错诊断计划与察觉提供必要改进即时性质和更好的鉴定精确性。

  • 标签: 监视传感器 诊断 鉴定方法 支持向量 MTI 精确性
  • 简介:Asimplelayer-by-layerdepositiontechniquewasusedtofabricatethemultilayerthinfilmsofunmodifiedsilvertriangularnanoplates(AgTNPs).ThemultilayerofAgTNPsthinfilmswerefabricatedbyalternatedepositionofeachanionicsodiumcitratestabilizedAgTNPsandcationicpoly(diallyldimethylammoniumchloride).AllpreparedAgTNPsmultilayerthinfilmswereexhibitedastrongplasmonbandatthewavelengthof667nm,whichconfirmedtheformationofAgTNPsontothesubstrate.Thecharacteristicsofthemultilayerthinfilmswereinvestigatedusingcontactanglemeasurement,UV-visiblespectroscopy,X-raydiffractionanalysis(XRD),atomicforcemicroscope(AFM)andfieldemissionscanningelectronmicroscope(FESEM).Asthesefilmsaretobeusedasamercury(II)colorimetricsensor,thechangesinopticalpropertiesofthefilmswereevaluatedforvariousmercury(Ⅱ)concentrations.AgTNPsassembledintothinfilmsshowedastrongcolorshiftfrombluetomauveandcolorlesswhenexposedtomercury(Ⅱ).Theconstructedmultilayerthinfilmsexhibitedexcellentcolorchangesofmercury(II)withalinearrangebetween0.5and20ppm.Thelimitofdetection(LOD)andlimitofquantitation(LOQ)were0.45±0.002and1.52±0.002ppm,respectively.TherecoveryvaluesofAgTNPsmultilayerthinfilmsaresatisfactoryintherangeof100.1%-106.4%whenappliedtodeterminingmercury(Ⅱ)inwatersamples.

  • 标签:
  • 简介:ThelocalCa^2+releasefromtheheterogeneouslydistributedendoplasmicreticulum(ER)calciumstorehasacriticalroleincalciumhomeostasisandcellularfunction.However;singlefluorescentproteinbasedERcalciumprobesexperiencechallengesinquantifyingtheERcalciumstoreindifferinglivecells,andintensity-basedmeasurementsmakeitdifficulttodetectlocalcalciummicrodomainsintheER.Here,wedevelopedageneticallyencodedratiometricERcalciumindicator[GCEPIA1-SNAPer]thatcandetectthereal-timeERcalciumstoreandlocalcalciummicrodomainsinlivecells.GCEPIA1-SNAPerwaslocatedinthelumenoftheERandshowedalinear;reversibleandrapidresponsetochangesintheERcalciumstore.TheGCEPIA1-SNAPerprobeeffectivelymonitoredthedepletionoftheERcalciumstorebyTGorstarvationtreatment,andthrough让suseweidentifiedheterogeneouslydistributedcalciummicrodomainsintheERwhichwerecorrelatedw让hthedistributionofSTIM1clustersuponERcalciumstoredepletion.Lastly,GCEPIA1-SNAPercanbeusedtodetecttheERcalciumstorebyhigh-throughputflowcytometryandconferstheabilitytostudythefunctionofcalciummicrodomainsoftheER.

  • 标签: RATIOMETRIC CALCIUM sensor LOCAL CALCIUM microdomain
  • 简介:Underwatersensornetwork(UWSN)adoptsacousticcommunicationwithmoreenergy-consumptionandlongerpropagation-delay,whichbringgreatchallengestoprotocoldesign.Inthispaper,weproposedlevel-basedadaptivegeo-routing(LB-AGR)protocol.LB-AGRdividestrafficsintofourcategories,androutesdifferenttypesoftrafficinaccordancewithdifferentdecisions.Packetsupstreamtothesinkareforwardedunicasttothebestnext-hopinsteadofbroadcastingtoallneighbornodesasinpresentUWSNroutingprotocols.LB-AGRdefinesanintegratedforwardingfactorforeachcandidatenodebasedonavailableenergy,density,location,andlevel-differencebetweenneighbornodes,whichisusedtodeterminethebestnext-hopamongmultiplequalifiedcandidates.Throughsimulationexperiments,weshowthepromisingperformanceofLB-AGR.

  • 标签: 传感器网络 路由协议 自适应 水下 地理 相邻节点
  • 简介:Anultrasensitivemagneticfieldsensorbasedonacompactin-fiberMach–Zehnderinterferometer(MZI)createdintwin-corefiber(TCF)isproposed,anditsperformanceisexperimentallydemonstrated.AsectionofTCFwassplicedbetweentwosectionsofstandardsingle-modefibers,andthenamicrochannelwasdrilledthroughonecoreoftheTCFbymeansoffemtosecondlasermicromachining.TheTCFwithonemicrochannelwasthenimmersedinawater-basedFe3O4magneticfluid(MF),formingadirectcomponentofthelightpropagationpath,andthensealedinacapillarytube,achievingamagneticsensingelement,whichmergestheadvantagesofanMZIwithanMF.Experimentswereconductedtoinvestigatethemagneticresponseoftheproposedsensor.Thedevelopedmagneticfieldsensorexhibitsalinearresponsewithinameasurementrangefrom5to9.5mTandanultrahighsensitivityof20.8nm/mT,which,toourbestknowledge,is2ordersofmagnitudegreaterthanotherpreviouslyreportedmagneticsensors.Theproposedsensorisexpectedtooffersignificantpotentialfordetectingweakmagneticfields.

  • 标签:
  • 简介:Inthispaperthesolar-blindultraviolet(UV)lightisusedascommunicationmediumforwirelesssensornetworks(WSNs).ThreetypesofsinglescatteringUVcommunicationmodelsareintroducedandadirectionalfloodingmodelisproposed,whicharebasedonthedirectionalityoftheUVcommunicationandthetraditionalfloodingroutingmodel.Thedelay,delayjitter,throughputandenergyconsumptionofthethreetypesofcommunicationsofthenewmodelaresimulatedandcompared.Theresultsindicatethattheproposeddirectionalfloodingmodelcaneffectivelyavoidtheunidirectionalityandtheblindnessofthetraditionalfloodingbroadcastmessages.Theenergyconsumptionofnodesinthenetworkisreducedandthelifecycleofthenetworkisextended.

  • 标签: 无线传感器网络 太阳紫外线 网络路由算法 洪水演进 紫外光通信 延迟抖动
  • 简介:Thispaperpresentsacollaborativebeamforming(CB)techniquetoorganizethesensornode'slocationinalineararrayforgreenwirelesssensornetwork(WSN)applications.Inthismethod,onlyselectedclustersandactiveCBnodesareneededeachtimetoperformCBinWSNs.Theproposedleast-squarelineararray(LSLA)managestoselectnodestoperformasalinearantennaarray(LAA),whichissimilartoandasoutstandingastheconventionaluniformlineararray(ULA).TheLSLAtechniqueisalsoabletosolvepositioningerrorproblemsthatexistintherandomnodesdeployment.Thebeampatternfluctuationshavebeenanalyzedduetotherandompositionsofsensornodes.Performancesintermsofnormalizedpowergainsaregiven.ItisdemonstratedbyasimulationthattheproposedtechniquegivessimilarperformancestotheconventionalULAandatthesametimeexhibitslowercomplexity.

  • 标签: 无线传感器网络 线性阵列 波束赋形 最小平方 传感器节点 sla技术
  • 简介:磁性的液体(MF)充满了的高敏感方面洞纤维磁场传感器基于表面电浆子,回声(SPR)被设计并且调查。在方面洞纤维以内,以水为基的MF被注入二个方面洞,并且两洞与黄金是涂的由使用SPR效果认识到磁场的测量。MF的折射索引随着不同外部磁场变化,导致搬到另外的波长的反响的波长。而且,当外部磁场从30~210.9Oe增加时,磁场敏感能到达nm/Oe到1.063。

  • 标签: 表面等离子体共振 光纤磁场传感器 高灵敏度 侧孔 SPR效应 边孔光纤
  • 简介:Aschemeisproposedtoelevatethelimitationofthegroundapplicationsystemofmono-satellite-sensorundertherequirementofremotesensingsatellitegroundapplicationsystem.Intheresource-sharing,forinstancecaculatingresource,asimplephototypeofcaculating-resourceisproposedthroughanalyzingresourceassignment,applicationassignment,bodystructure,andsoon.Inordertoimprovetheabilityofassignment,realizethefavorableutility,management,andmaintenance,thephototypeisimprovedbyusingdatagridcalculationaccordingtotherequirementandcharacterofactualapplication.Thephototypecanbetakenasthefoundationofcalculationframeofremotesensinggroundapplicationsystemofmulti-satelliteandmulti-sensor.

  • 标签: 卫星 多传感器 信息共享 数据栅格
  • 简介:Inexperimentalstudyofthetindioxidegassensor,insitusheetconductivitywasmeasuredwithultrahighvacuumfourpointresistivityprobe.Surfacecompositionandstoi-chiometryweredetectedusingXPS.FourseparatestructurephaseswereobtainedbyLEEDatdifferentannealingtemperature,andemissionwasobservedthroughoutthebandgapuptotheFermilevelwithUPS.Furthermore,effectsofannealingtemperatureanddosedoxygenpressureonthesurfacereconstruction,O/Snratio,sheetconductivity,variationoftheworkfunctionandbandbendinghavebeenalsoinvestigated.Theresultshelpustorevealtherelationshipsbetweentheelectronicandelectricalpropertiesofthematerialanditsnativedefectsstructure.Itises-peciallyusefultoprovideamorecompleteunderstandingofthebasicoperationmechanismsforsuchsensingmaterials.

  • 标签: Sensor CONDUCTIVITY STOICHIOMETRY Reconstruction ANNEALING