学科分类
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7 个结果
  • 简介:Speckleinterferometryisanefficientmethodtoanalyzeavibration.Incetrainconditions,thistechniquehassomeoutsandingadvantage,andneednotstrictshock-proofcondition,comparedwiththeholographicmethodformeasuringvibration,Therefors,itissuitabletoanayyzeavibrationwithalogaramplitude.Real-timeinterferometryisarapidandsimplemethodformeasuringvibrationofabody,givesspecklepatterncontainingamplitudedistributionofbody-surface.Bymeansoftime-averagedmethod.thespecklepatternisrecordedinFouriertransformplane.orvibra-tionlinesareseendirectlywitheyes,soastoanalyzeefficientlyampitude.phase,andmod-elofavibration.Thispaperdeducestheintensitydistributionfunctionwithreal-timemethod,andgivesexpermentaldemonstrationofvibrationbody-thevibrationlineswithdifferentfrequencies.

  • 标签: 振动测量 振动曲线 实时测量 斑线干涉仪
  • 简介:Thealgorithmofautonomousorbitdeterminationfortheprobearoundsmallbodyisstudied.Inthealgorithm,first,theobservedimagesofthebodyarecomparedwithitspre-computedmodelofthebodytoobtainthelocationofthelimbfeaturesofthebodyintheinertialcoordinate.Second,theinformationoftheimagesandfeaturesinutilizedtoobtainthepositionoftheprobeusingtheLevenberg-Marquardtalgorithm.ThepositionistheninputtoanextendedKalmanfilterwhichdeterminestherealtimeorbitoftheprobe.Finally,consideringtheeffectiveoftheirregularsmallbodyshapeperturbationandthesmallbodymodelparametererrorontheorbitdeterminationprecise,theprocedureofautonomousorbitdeterminationisvalidatedusingdigitalsimulation.

  • 标签: 自主轨道确定 小物体探测 LEVENBERG-MARQUARDT算法 扩展卡尔曼滤波
  • 简介:ThisstudyconcernssecurityissuesoftheemergingWirelessBodySensorNetwork(WBSN)formedbybiomedicalsensorswornonorimplantedinthehumanbodyformobilehealthcareappli-cations.Anovelauthenticatedsymmetric-keyestablishmentschemeisproposedforWBSN,whichfullyexploitsthephysiologicalfeaturesobtainedbynetworkentitiesviathebodychannelavailableinWBSNbutnototherwirelessnetworks.Theself-definedIntrinsicSharedSecret(ISS)isusedtoreplacethepre-deploymentofsecretsamongnetworkentities,whichthuseliminatescentralizedservicesorau-thoritiesessentialinexistingprotocols,andresolvesthekeytransportprobleminthepuresymmet-ric-keycryptosystemforWBSNaswell.Thesecuritypropertiesoftheproposedschemearedemon-stratedintermsofitsattackcomplexityandthetypesofattacksitcanresist.Besides,theschemecanbeimplementedunderalight-weightwayinWBSNsystems.DuetotheimportanceoftheISSconcept,theanalysisonusingfalseacceptance/falserejectionmethodtoevaluatetheperformanceofISSforitsusageintheschemeisalsodemonstrated.

  • 标签: 医疗体域传感器网络 安全认证 对称密钥建立 生物医学传感器
  • 简介:Anewmethodformeasuring3-Drigidbodydisplacementsisproposed,inwhichtwoperpendicularbeamsareemittedontotwosensitiveplanesofPSDsleingperpendiculartoeachother.Themethodcanbeusedtomeasure1-Dor2-Ddisplacementswhenrequired.Moreover,theexperimentalresultsarepresented,whichdemonstratethatthenewmethodhashighaccuracy,fastprocessingspeed,highreliability,andeasilybeingrealized.

  • 标签: 显示测量 三维物体 光感测器
  • 简介:Anewmethodofcalculatingtheradaicrosssection(RCS)forwing-bodyblendedtargetsispresentedandverified.Themethodutilizesacomputerprogramformodelingtargets’geometryintermsofsmallpieces.Thecalculationisbasedonphysicalopticsapproximation.Examplesaregiventoshowthevalidityofthemethod.

  • 标签: RADAR CROSS section ELECTROMAGNETIC scattering.
  • 简介:DoubleBeamstoMeasureThree-dimensionalRigidBodyDisplacements①ZHOUJian,CHENWenyi,ZHAOHongTIANFeng,TANYushan(ResearchInstitutefo...

  • 标签: Displacements Measurement PHOTODETECTOR PSD
  • 简介:分泌物参数通过小移动手持金属杆从控告的人的身体在静电的分泌物(ESD)被测量并且计算。关联学习与费用电压以及途径速度在分泌物参数上被执行了。在费用电压800V,分泌物参数的差别由电极的快、慢的途径速度引起了被发现到达极端价值。为这种特殊情况探索原因,与一个短差距的ESD模型一起的分析被执行。

  • 标签: 静电放电 相互关系 充电电压 参数