简介：Inthispaper,anewtimingoffsetestimationmethodforOrthogonalFrequencyDivisionMultiplexing(OFDM)systemsarepresented.Uponthereceiptofjustonetrainingsequence,thispresenceofasignalandthestartoftheframecanbedetected.TheperformancesofthetimingestimatorinadditivewhiteGaussiannoiseandthemobilemultipathchannelareevaluatedbysimulation.TheresultsdeliveredbythisalgorithmarecomparedwiththosedeliveredbySchmidlandCox.

简介：Vibrationsofoffsetprintingpressesareseriousproblem,whichcausemanydifficultieswhileprintingandimpairqualityoftheprints.Thebiggestproblemliesinconstructionofprintingunit.Itmainlyconsistsofthreecylinders,buttwoofthemareinadirectcontactgenerateundesiredvibrations.Constructionofthecylindersmakesthatstiffnessoftheunitvariesperiodicallywhileprinting.Inthispapermodelofoffsetprintingunitispresented.Themodelisdescribedbythesystemoftwoparametricdifferentialequations.Computersimulationsofthebehaviouroftheprintingunithavebeenperformed.Conditionsinwhichparametricresonanceappearsarealsoappointedhere.

简介：AnoveloffsetFresnelZonePlatereflectorAntenna(FZPA)isproposed,thephasecorrectingzoneofthisFZPAiselliptic.BasedonPhysicalOpticsMethod,thefocusingcharacteristicsofthereflectorareanalyzed.ThecomparisonofthisnewFZPAwiththecircularFZPAandMawzonesFZPAismade.

简介：OneoftheprincipaldisadvantagesofOrthogonalFrequencyDivisionMultiplexing(OFDM)isverysensitivetocarrierfrequencyoffset.Theintegerfrequencyoffsethasnoeffectontheorthogonalityamongthesubcarriers,butitcausesacircularshiftandphaserotationofthereceiveddatasymbolssequence,resultinginaBitErrorRate(BER)of0.5.Inthispaper,anovelintegerfrequencyoffsetestimatorforOFDMisderivedbasedonmaximumlikelihoodestimationtechniqueandexplorationofthedifferentialrelationbetweentwoconsecutiveOFDMdatasymbolsequencesinfrequencydomain.ItsperformanceiscomparedwiththeconventionalmethodbycomputersimulationsfortheadditivewhiteGaussiannoisechannelandamultipathfadingchannel.Simulationresultsshowthattheperformanceoftheproposedestimatorisbetterthantheconventionalestimator.

简介：Bundledhybridoffsetriser(BHOR)globalstrengthanalysis,whichismorecomplexthansinglelineoffsetriserglobalstrengthanalysis,wascarriedoutinthispaper.Atfirst,theequivalenttheoryisusedtodealwithBHOR,andthenitsglobalstrengthinmanifoldcaseswasanalyzed,alongwiththeuseofathree-dimensionalnonlineartimedomainfiniteelementprogram.Sothemaxbendingstress,maxcircumferentialstress,andmaxaxialstressintheBHORbundlemainsection(BMS)wereobtained,andthevaluesofthesethreestressesineachriserwereobtainedthroughthe'stressdistributionmethod'.Finally,theMaxVonMisesstressineachriserwasgivenandacheckwasmadewhetherornottheymetthedemand.Thispaperprovidesareferenceforstrengthanalysisofthebundledhybridoffsetriserandsomeotherbundledpipelines.

简介：针对广义offset在实际中的广泛应用,给出一种曲线、曲面的广义offset的定义,并讨论它们的性质.

简介：高度精确的声学的阻抗倒置是为预先钻的一种关键技术由VSP数据的预言。在这篇论文，基于VSP数据有高分辨率的事实，高发信号到噪音比率，并且下面去并且在去上面，波浪能精确地被分开，我们建议用VSP数据在位前面在地上凿穿下面预言阻抗的一个方法。首先，非线性的反复的倒置的方法被采用用VSP走廊栈为阻抗转换。然后，由在重复并且用preconditioned修改抑制因素结合坡度方法解决倒置结果的方程，稳定性和集中能被提高。理论模型和实际数据的结果证明方法为预先钻是有效的预言使用VSP数据。

简介：Thepartialchargesimulationmethodispresentedtosolvethecharacteristicimpedanceofthetransmissionlineofspecificcrosssectionwithanoffsetinnerconductor.Thismethodhasahigheraccuracyduetotheaccuratesatisfactionoftheboundaryconditionontheouterconductor.ThecombinedmethodoftheGausseliminationandoptimizationisusedtosolvetheequationofchargesimulation,anditisaneffectivemethodforincreasingtheaccuracyandassuringtheconvergence.TheGreen’sfunctionsoffivetransmissionlines(i.e,withcircular,elliptic,rectangular,troughandslabconductor)aregiven.

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简介：Theaveragebondenergymethodispopularizedandappliedtostudybandoffsetsatstrainedlayerheterojunctions.BycarefulexaminationofhydrostaticanduniaxialstrainactionsonthebandoffsetparameterEmv,itisfoundthattheaveragebandoffsetparameterEmv,av=Em-Ev,avremainsbasicallyunchangedunderdifferentstrainconditions.Therefore,providedthebandoffsetparameterbeforestrainEmv,0ofbulkmaterialiscalculated,andtheexperimentvaluesofdeformationpotentialbandspin-orbit(SO)splittingenergy△0arequoted,theEmvatstrainedlayercanbeobtainedbyasimpleandconvenientalgebraiccalculation.Thusthevalencebandoffset△Evatstrainedlayerheterojunctincanalsobepredictedconveniently.Thissimplifiedcalcultationmethodischaracterizedbydecreasedcalculationamountandincreasedconvictionduetouseasmanyaspossibletheexperimentvalues.

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简介：Recenthigh-resolutiondeepseismicreflectionprofileacrosstheKunlunfaultinnortheasternTibetshowsclearlythattheMohoiscutoffbyacomplexthrustfaultsystem.Mohooffsetisageneralphenomenon,butlittleisknownaboutthedynamicmechanism.Inthisstudy,contactmodelswithMaxwellmaterialsareusedtosimulatethemechanicalprocessofMohooffsetinducedbytheaseismicslipofdeeplyburiedfaults.Basedontheseismicreflectiondata,weprojectasinglefaultmodelandacomplexfaultsystemmodelwithtwofaultsintersecting.ThedeformationsoftheMoho,theaseismicslips,andcontactstressesonfaultsindifferentmodelsarediscussedindetail.ResultsshowthattheMohooffsetmightbeproducedbyaseismicslipofdeeplyburiedfaults,andthemagnitudeisinfluencedbythefrictioncoefficientoffaultsandtheviscosityofthelowercrust.ThemaximumslipoccursneartheMohoonthesinglefaultoratthecrossingpointoftwointersectingfaultssystem.StressconcentratesmainlyontheMoho,thedeependoffaults,orthecrossingpoint.ThisstudywillthrowlightonunderstandingthemechanismofMohooffsetandaseismicslipofdeeplyburiedfaults.Theresultsofcomplexfaultsystemwithtwofaultsintersectingarealsousefultounderstandtheshallowintersectingfaultsthatmaycauseearthquakes.

简介：摘要目的研究后装治疗中多种施源器的Offset值。方法选取插植钢针(Part#083.062)、插植塑料圆针(Part#189.608)、插植塑料尖针(Part#189.601)、多通道施源器软管(Part#110.800)、塑料宫腔管(Part#189.745)、金属宫腔管(Part#110.437)施源器。根据源在荧光胶片放射性成像，确定施源器顶端驻留点位置以及到施源器顶端的距离。在施源器顶端驻留点位置贴铅珠，将施源器置入盆腔体模中进行CT扫描。然后在计划系统中重建施源器，通过调整Offset值使铅珠与施源器顶端驻留点对准，从而得到施源器Offset值。塑料材质施源器由于密度与人体组织接近，施源器顶端难以准确重建，因此利用挡块或者假源重建施源器，得到塑料材质施源器Offset值。根据验证结果分析比较不同施源器Offset值差异。结果不同施源器Offset值存在较大差异，其中插植钢针为－11.4 mm，插植塑料圆针为－4.1 mm，插植塑料尖针为－3.5 mm，多通道施源器软管为0 mm或－5.0 mm，塑料宫腔管为－6.5 mm，金属宫腔管为－7.5 mm。结论为了适应精确放疗的发展趋势，有必要对后装中施源器Offset值进行测量验证。

简介：Duetotheexistenceofthermaloffsets,globalsolarirradiancesmeasuredbypyranometersaresmallerthanactualvalues,anderrorsarelargerinthedaytime.Untilnow,thereisnouniversally-recognizedcorrectionmethodforthermaloffseterrors.Therefore,itisimperativetoidentifyaconvenientandeffectivecorrectionmethod.Fivecorrectionmethodswereevaluatedbasedonthedatameasuredfromafieldexperimentfrom23Januaryto15November,2011.Resultshaveshown:1)Temporalvariationcharacteristicsofthermaloffsetsinthefourtestedpyranometersareconsistent.2)Amongthefivemethods,non-dimensionalquantitymethodissuggestedforusetocorrectthermaloffsets,becauseitisconvenientandnomodificationofinstrumentsisrequired.Ifcollocatednetlongwaveradiationandwindspeeddataareavailableandtheiruncertaintiesaresmall,thehistoricalsolarradiationdatasetscanalsobecorrected.Andcorrectioneffectsbythemethodarebetter.

简介：Excel内置的功能中只有“方案管理器”可以处理多变量情况下的假设分析，但该功能存在若干不足之处。本文中笔者新创了一种基于OFFSET函数的方法来替代方案管理器，以改进Excel下的多变量假设分析功能。

简介：帮助递归的最少的广场(RLS)的平行干扰取消(照片)算法被建议在直角的频率部门multiplexing(OFDM)由于搬运人频率偏移量(CFO)取消干扰系统。建议算法由二个阶段组成，它是RLS计划和照片计划。RLS计划被选择在第一个阶段在时间领域补偿频率偏移量，并且干扰由剩余频率偏移量导致了被PIC计划在第二个阶段在频率领域取消。位错误率(BER)的结果证明它的性能作为比较标准为取消是柔韧的，尽管频率偏移量是0.45。16QAM星座也被模仿从建议抑制计划观察改进。

简介：MostoftheblindOrthogonalFrequencyDivisionMultiplexing(OFDM)CarrierFrequencyOffset(CFO)estimatorsnecessitatelargenumberofsamplestoensuretheestimationaccuracy.However,thenumberofsamplescannotbeselectedtoolargebecauseofthecarrieroffsetdrift.Inthisletter,anewclosedformalgorithmforblindOFDMCFOestimationinfrequency-selectivechannelisproposed.Thismethodutilizesthepropagatorobtainedfromdatamatrixandthediagonalloadingtechnique,thusithasbetterperformanceevenonlyusingoneortwoOFDMblocks.Furthermore,therangeoftheCFOestimationwhichcanbehandledisoveralltransmissionspectral.Simulationresultsconfirmitseffectiveness.

简介：在这篇论文，我们使用到完全的变换波浪的移植(POM)预先叠的伪偏移量的方法有在各向异性的媒介的振幅保藏的时间移植。进普通变换的原来的踪迹散布的方法地图指(CCSP)由POM直接聚在一起，它为变换波浪简化常规处理过程。POM集合褶层和SNR高，它为速度分析是有利的并且对有低SNR的地震数据特别合适。我们使用了相等的各向异性的理论计算各向异性的参数。在VTI媒介基于散布波浪旅行时间方程，在各向异性的媒介的POM伪偏移量迁居被推出。由保存振幅的POM集合印射，速度分析，栈处理等等，各向异性的移植结果被获得。处理的向前当模特儿的计算和实际数据证明变换波浪的有效性预先叠有用各向异性的POM方法的振幅保藏的时间移植。

简介：Fiber-opticlaser–ultrasoundgenerationisbeingusedinanincreasingnumberofapplications,includingmedicaldiagnosis,materialcharacterization,andstructuralhealthmonitoring.However,mostcurrentlyusedfiber-opticultrasonictransducersalloweffectiveultrasoundgenerationatonlyasinglelocation,namely,atthefibertip,althoughtherehavebeenafewlimitedproposalsforachievingmultipointultrasoundgenerationalongthelengthofafiber.Herewepresentanovelfiber-opticultrasoundtransducerthatusesthecore-offsetsplicingoffiberstoeffectivelygenerateultrasoundatmultiplelocationsalongthefiber.Theproposedlaser–ultrasonictransducercanproduceabalancedstrengthsignalbetweenultrasonicgenerationpointsbyreasonablycontrollingtheoffsetsofthefibers.Theproposedtransducerhasotheroutstandingcharacteristics,includingsimplefabricationandlowcost.

简介：AIM:Toinvestigatewhethertheresponseofacentralhexagonalelementcorrespondingtothemacularareainconventionalmultifocalelectroretinography(mfERG)testswasthesameasthatofexperimentalmfERGusingsinglecentralhexagonalelementstimulation.METHODS:Prospective,observationalstudy.Thirtyhealthysubjectswereincludedinthisstudy.mfERGrecordingswereperformedaccordingtotwoprotocols:stimuluswith37hexagonalelements(protocol1),andstimuluswithasinglecentralelementcreatedbydeactivatingtheother36hexagonalelements(protocol2).Wecompareddifferencesbetweenring1parametersineachprotocol.RESULTS:Inprotocol1,thefirstpositivecomponent(P1)implicittimeandP1amplitudewere37.8±1.8msand6.3±2.7μV.Aftersingleelementstimulation(protocol2),doublepositivewavesappeared.TheimplicittimeandamplitudeofP1were40.7±2.4ms(P<0.001)and9.1±3.3μV(P=0.001),respectively.Theimplicittimeandamplitudeofthesecondpositivecomponent(P2)were68.0±4.5ms(P<0.001,comparedwithP1inprotocol1)and12.3±4.7μV(P<0.001,comparedwithP1inprotocol1),respectively.TheamplitudeofP2inprotocol2wasabouttwotimeshigherthanthatofP1inprotocol1.CONCLUSION:mfERGresponsesofacentralhexagonalelementinasingleelementstimulationprotocolaredifferentfromthoseofmultipleelementstimulation.Thepositivewaveismoreenhancedcomparedtothatoftheconventionalprotocolanditelongatedintotwowavelets.