简介：AtypeofsilicondetectorknownasAXUV(absoluteextremeultraviolet)photodiodesissuccessfullyusedtomeasuretheradiatedpowerinEAST.Thedetectorischaracterizedbycompactstructure,fasttemporalresponse(<0.5s)andflatspectralsensitivityintherangefromultra-violettoX-ray.Two16-channelAXUVarraysareinstalledinEASTtoviewthewholepoloidalcross-sectionofplasma.Basedonthediagnosticsystem,typicalradiationdistributionsforbothlimiteranddivertorplasmaareobtainedandcompared.Asdivertordetachmentoccurs,theradiationdistributioninX-pointregionisobservedtovarydistinctly.Thetotalradiationpowerlossesindischargeswithdifferentplasmaparametersarebrieflyanalyzed.

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简介：这块地水平地极化了超声砍2/2散发的波浪压电的合成正常探查被学习。严格地，二不同表面力量的分析领域解决方案被推出，领域分发和择向性模式被数字计算给。垂直的散发的地砍波浪理论上并且与实验相比被获得。择向性模式的试验性的结果遵守了理论预言，它为变换器的设计申请提供了理论基础。

简介：Onthebasisofenvelopespectrumanalysisofship-radiatednoise,thefeaturesandtheextractingmethodsarediscussed,andthenanewmethodofdynamicrecognitionhasbeenproposed.Usingthismethod,accuraterecognitionratefordifferenttypesofshiptargetscanbeeffectivelyimproved,andsomeoftheimportantparametersoftarget'smovementcanbeobtainedatthesametime.

简介：超声的短暂的地水平地极化了砍2/2散发的波浪压电的合成正常探查被分析。二不同表面力量来源的分析的地解决方案被推出，中央剖面图上的短暂排水量地分发被数字计算阴谋。直接波浪和边波浪以及头波浪在阴谋清楚地被观察。时间域波形的试验性的结果符合了理论预言，它在变换器的短暂的域附近支持了理论、数字的结果。

简介：Pantographsystemofhigh-speedtrainsbecomesignificantsourceofaerodynamicnoisewhentravellingspeedexceeds300km/h.Inthispaper,ahybridmethodofnon-linearacousticsolver(NLAS)andFfowcsWilliams-Hawkings(FW-H)acousticanalogyisusedtopredicttheaerodynamicnoiseofpantographsysteminthisspeedrange.Whenthesimulationmethodisvalidatedbyabenchmarkproblemofflowsaroundacylinderoffinitespan,wecalculatethenearflowfieldandfaracousticfieldsurroundingthepantographsystem.Andthen,thefrequencyspectraandacousticattenuationwithdistanceareanalyzed,showingthatthepantographsystemnoiseisatypicalbroadbandonewithmostacousticpowerrestrictedinthemedium-highfrequencyrangefrom200Hzto5kHz.Theaerodynamicnoiseofpantographsystemsradiatesoutwardsintheformofsphericalwavesinthefarfield.Analysisoftheoverallsoundpressurelevel(OASPL)atdifferentspeedsexhibitsthattheacousticpowergrowsapproximatelyasthe4thpoweroftrainspeed.Thecomparisonofnoisereductioneffectsforfourtypesofpantographcoversdemonstratesthatonlycase1canlessenthetotalnoisebyabout3dBasbafflesonbothsidescanshieldsoundwaveinthespanwisedirection.ThecoversproduceadditionalaerodynamicnoisethemselvesintheotherthreecasesandleadtotheriseofOASPLs.

简介：Inordertoimprovetheperformanceoflinespectrumdetection,accordingtothefeaturethattheunderwatertargetradiatednoisecontainingstablelinespectrum,thedifferencesofthephasedifferencebetweenlinespectrumandbackgroundnoise,aweightedlinespectrumdetectionalgorithmbasedonthephasevarianceisproposedinfrequencydomain.Afterphasedifferencealignment,thephasevarianceoflinespectrumandthephaseofbackgroundnoise,respectively,aresmallandbiginfrequencydomain,thismethodutilizestheweightedstatisticalalgorithmtocumulatethefrequencyspectrumbasedonthephasevariance,whichcanrestrainthebackgroundnoisedisturbance,andenhancethesignaltonoiseratio(SNR).Thetheoryanalysisandexperimentalresultsbothverifythattheproposedmethodcanwellenhancetheenergyoflinespectrum,restraintheenergyofbackgroundnoise,andhavebetterdetectionperformanceunderlowerSNR.

简介：Tosolvebladenumbercharacteristicextractionproblemoflownoiseships,phasecharacteristicsofshipradiated-noisedemodulationspectrumharmoniccomponentsusinghigherorderspectrumanalysiswereconsidered.Throughanalyzingalargenumberofshipradiatednoisedata,itpointsouttheexistingphasecouplingrelationshipbetweentwoorthreeharmoniccomponentsofdemodulationspectrum.Thephasedifferencebetweenlinespectrumofbladefrequencyandthesumoflinespectrumatshaftfrequencyanditssomeharmoniccommonlyiszeroorotherconstant.Higher-ordercumulantisgivenandhigher-orderspectrumissimulatedwhenabovephasedifferenceisanon-zeroconstant.Theapplicationofphasecouplingrelationshipisstudied.Accordingtothehigher-orderspectralanalysisofsomeweakmodulatedshipradiatednoise,itisindicatedthatthephasecouplingrelationshipandhigher-orderspectralanalysiscanimprovetheabilitytoextractpropellerparameters,especiallyfortheweakmodulation.

简介：TheradiatedfieldsGaussianDistributedAperture(GDA)canbeapproximatelyanalyzedbytheComplexRayMethod(CRM).Inthisarticle,theradiatedfieldsderivedintermsofplanewavespectrumintegralareusedasstandard,andtheerrorsourceofthereplacementbycomplexrayfieldsisfound.WithdiscussionsontheerrorcharacteristicsofthisCRMapproximation,conclusionsaredrawnwhichareexpectedtobehelpfulinapplicationsofCRM.

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简介：多层的印刷电路董事会(聚氯联苯)的放射排放(RE)将引起电磁的相容性问题。在聚氯联苯的飞机被介绍的为在从力量地面(P/G)减少RE评估去耦电容器的有效性的一个有效数字方法。一个二维的边界元素方法(BEM)被用来建立放射模型。然后，RE被边地的相等的磁性的电流在P/G飞机附近计算。而且，P/G飞机的放射和输入阻抗装了去耦电容器为频率被计算直到5GHz。没有去耦电容器，结果与盒子的那些相比。它证明去耦电容器有效地除了反反响的频率装减少RE。在更高的频率，去耦有效性主要取决于电容器大头针而非价值的寄生电感。