简介：设计了一款反激式隔离型高频变压器。该高频变压器工作于反激变换状态,主要应用于基于BP9022A作为反馈控制芯片的电路中。给出了该高频变压器的详细设计步骤和绕制流程,这些步骤包括原副边匝数、原副边漆包线线径、原边感量的计算等。基于该反激式高频变压器的电源效率可达80%,电流的输出精度可达±6%,整机成本不到1.3元,具有极高的性价比。

简介：综述了国内外快放电直线型变压器驱动源（fastlineartransformerdriver,FLTD）闪光照相加速器的研究进展,包括美国圣地亚国家实验室（SandiaNationalLaboratory,SNL）双轴7MVLTD型闪光照相装置、洛斯·阿拉莫斯国家实验室LANSCE装置C区与质子照相装置轴垂直的LTD型闪光照相装置、21级串联LTD-MinorURSA装置及32级串联正负极性可调的LTD装置的概念设计。同时,介绍了法国原子能部CEA/PAM8MVLTD型照相装置IDERIX和英国原子能武器中心为替代Mevex加速器拟研制的空气绝缘LTD的概念设计。最后,介绍了中国工程物理院和西北核技术研究所FLTD相关研究进展,结合西北核技术研究所现有技术条件和需求,提出了开展闪光LTD驱动源的初步设想。

简介：Bythemethodofdynamicalsystem,weconstructtheexacttravellingwavesolutionsofanewHamiltonianamplitudeequationandtheOstrovskyequation.Basedonthismethod,thenewexacttravellingwavesolutionsofthenewHamiltonianamplitudeequationandtheOstrovskyequation,suchassolitarywavesolutions,kinkandanti-kinkwavesolutionsandperiodictravellingwavesolutions,areobtained,respectively.

简介：Withanincreasingemphasisonrenewableenergyresources,wavepowertechnologyisbecomingoneoftherealisticsolutions.However,the2011tsunamiinJapanwasaharshreminderoftheferocityoftheocean.Itisknownthattsunamisarenearlyundetectableintheopenoceanbutasthewaveapproachestheshoreitsenergyiscompressed,creatinglargedestructivewaves.Thequestionposedhereiswhetheranoscillatingwavesurgeconverter(OWSC)couldwithstandtheforceofanincomingtsunami.Severaltoolsareusedtoprovideananswer:ananalytical3Dmodeldevelopedwithintheframeworkoflineartheory,anumericalmodelbasedonthenon-linearshallowwaterequationsandempiricalformulas.Numericalresultsshowthatrun-upanddraw-downcanbeamplifiedundersomecircumstances,leadingtoanOWSClyingondryground!

简介：Wavepropagationintwo-dimensionalhierarchicalhoneycombstructureswithtwoorderhierarchyisinvestigatedbyusingthesymplecticalgorithm.Byapplyingthevariationalprincipletothedualvariables,thewavepropagationproblemistransformedintoatwo-dimensionalsymplecticeigenvalueproblem.Thebandgapsandspatialfilteringphenomenaareexaminedtofindthestopbandsanddirectionalstopbands.Specialattentionisdirectedtotheeffectsoftherelativedensityandthelengthratioonthebandgapsandphaseconstantsurfaces.Thisworkprovidesnewopportunitiesfordesigninghierarchicalhoneycombstructuresinsoundinsulationapplications.

简介：Inthispaper,weuseamethodinordertofindexactexplicittravelingsolutionsinthesubspaceofthephasespaceforCH2equations.Thekeyideaisremovingacoupledrelationforthegivensystemsothatthenewsystemscanbesolved.Theexistenceofsolitarywavesolutionsisobtained.Itisshownthatbifurcationtheoryofdynamicalsystemsprovidesapowerfulmathematicaltoolforsolvingagreatmanynonlinearpartialdifferentialequationsinmathematicalphysics.

简介：Theassessmentofthewave-inducedsoilliquefactionplaysakeyroleinthegeotechnicaldesignforoffshorefoundations.Theunderlyingshortcomingsoftheexistingmomentaryliquefactioncriteriaareidentifiedandclarifiedbymechanismanalysesandtherecentfieldobservations.Amodifiedcriterionforthewave-inducedmomentaryliquefactionofasandyseabedisgiventodescribetheverticalporepressuredistributions.Animprovedapproximationofthemomentaryliquefactiondepthisfurtherpresented.Parametricstudyoftheeffectsofthesaturationdegreeofsoilsindicatesthatthismodificationissignificantfortheevaluationofwave-inducedmomentaryliquefaction.

简介：Basedonthetheoryofcomplexfunctionandtheprincipleofhomogenization,harmonicdynamicsstressofaradiallyinfiniteinhomogeneousmediumwithacircularcavityisinvestigated.Duetothesymmetry,wavevelocityisassumedtohavepower-lawvariationintheradialdirectiononly,andtheshearmodulusisconstant.TheHelmholtzequationwithavariablecoefficientisequivalentlytransformedintoastandardHelmholtzequationwithageneralconformaltransformationmethod(GCTM).Thedisplacementsandstressfieldsareproposed.Numericalresultsshowthatthewavenumberandtheinhomogeneityparameterofthemediumhavesignificanteffectsonthedynamicstressconcentrationaroundthecircularcavity.Thedynamicstressconcentrationfactor(DSCF)becomessingularwhentheinhomogeneityparameterofmediumisclosetozero.

简介：当量力学，严肃，和热力学同时被考虑时，我们考虑量波浪包的重力的效果。在严肃的热力学的起源的假设下面，我们建议一个一般方程描述量波浪包的重力的效果。在古典限制，这个方程同意引力的牛顿法律。为量波浪包，然而，它预言排斥重力的效果。我们用超流体氦建议一个试验性的计划测试这排斥重力的效果。我们的研究证明与象超导的gravimetry和冷原子interferometry那样的现在的技术，为超流体氦的排斥重力的效果的测试在试验性的活动范围以内。

简介：Agraphene-coatedmicrofiber(GCM)-basedhybridwaveguidestructureformedbywrappingmonolayergraphenearoundamicrofiberwithlengthofseveralmillimetersispumpedbyananosecondlaserat~1550nm,andmultiordercascadedfour-wave-mixing(FWM)iseffectivelygenerated.Byoptimizingboththedetuningandthepumppower,suchaGCMdevicewithhighnonlinearityandcompactsizewouldhavepotentialforawiderangeofFWMapplications,suchasphase-sensitiveamplification,multi-wavelengthfilter,all-opticalregenerationandfrequencyconversion,andsoon.

简介：我们学习二维(2D)在吝啬地的模型的事波浪solitons在2D空间与远程的quadrupolequadrupole相互作用(QQI)由电的四极粒子形成了。在空间的2D事波浪solitons的存在用2DGrossPitaevskii方程(GPE)被预言。我们发现QQIsolitons比dipoledipole相互作用(DDI)有一个更高的团(更小的尺寸和更高的紧张)和更强壮的anisotropy在一样的环境参数下面的solitons。在在2D空间的二相同QQIsolitons之间的各向异性的solitonsoliton相互作用被学习。而且，稳定的各向异性的偶极子solitons被观察到我们的知识，第一次在在各向异性的非局部的立方的非线性下面的2D空间。

简介：Theinteractionofanti-planeelasticSHwaveswithaperiodicarrayofinterfacecracksinamulti-layeredperiodicmediumisanalyzedinthispaper.AperfectperiodicstructurewithoutinterfacecracksisfirststudiedandthetransmissiondisplacementcoefficientisobtainedbasedonthetransfermatrixmethodinconjunctionwiththeBloch-Floquettheorem.Thisisthengeneralizedtoasingleandperiodicdistributionofcracksatthecenterinterfaceandtheresultiscomparedwiththatofperfectperiodiccaseswithoutinterfacecracks.Thedependenceofthetransmissiondisplacementcoefficientonthefrequencyoftheincidentwave,theinfluencesofmaterialcombination,crackconfigurationandincidentanglearediscussedindetail.Comparedwiththecorrespondingperfectperiodicstructurewithoutinterfacecracks,anewphenomenonisfoundintheperiodiclayeredsystemwithasingleandperiodicarrayofinterfacecracks.

简介：All-opticalcanonicallogicunitsat40Gb/susingbidirectionalfour-wavemixing(FWM)inhighlynonlinearfiberareproposedandexperimentallydemonstrated.Cleartemporalwaveformsandcorrectpatternstreamsaresuccessfullyobservedintheexperiment.Thisschemecanreducetheamountofnonlineardevicesandenlargethecomputingcapacitycomparedwithgeneralones.ThenumericalsimulationsaremadetoanalyzetherelationshipbetweentheFWMefficiencyandthepositionoftwointeractionalsignals.

简介：UsingthestandardtruncatedPainlevexpansion,theresidualsymmetryofthe(2+1)-dimensionalmodifieddispersivewater-wavesystemislocalizedintheproperlyprolongedsystemwiththeLiepointsymmetryvector.Somedifferenttransformationinvariancesarederivedbyutilizingtheobtainedsymmetries.ThesymmetriesofthesystemarealsoderivedthroughtheClarkson-Kruskaldirectmethod,andseveraltypesofexplicitreductionsolutionsrelatetothetrigonometricorthehyperbolicfunctionsareobtained.Finally,somespecialsolitonsaredepictedfromoneofthesolutions.

简介：Thestudyofwaveguideinvariantinunderwateracousticsisoneofattractedtopicsinrecent30years.Theinterferencesofdirectwaveandreflectwavefromseasurfaceandseabottomofunderwatertargetradiatednoiseinherenttheinformationoftargetdistance.Extractionofthesedistanceinformationwillprovideapossiblenewwayinpassiverangingforunderwatertarget.ThetheoreticalanalysisandtheresultsofatseaexperimentsshowthattheLOFAR(LowFrequencyAnalysisRecord)figureinherentlycontainstherangeandmovinginformationofpassiveacousticsources,eveninthesituationthatthereceiverisonlyonesinglehydrophone.Thetheoreticalanalysisofextractionoftargetdistanceinformationbyusingwaveguideinvariantispresentedinthispaper.Itisshownthat,basedontheinterferencestriationpatternoftarget,thehydrophonearraysystemispossibletoextractthedistanceinformationwithquitehigharraygain.Althoughthemathematicalconstrainconditionsinforminginterferencestriationpatternaredifferentforindividualarrayelement,butitisprovedthatthedifferencesoftimedelaysbetweenarrayelementscanbeusedincompensationofbeamforming.Thetheoreticalanalysis,systemsimulationandsomeresultsofatseaexperimentshowanewwayinpassiverangingandtargetrecognition.

简介：Thefinite-dmerencetime-domam（FDTD）methodisproposedforanalyzingthesurfaceacousticwave（SAW）propagationintwo-dimensional（2D）piezoelectricphononiccrystals（PCs）atradiofrequency（RF）,andalsoexperimentsareestabhshedtodemonstrateitsanalysisresultofthePCs’bandgaps.TheFDTDmethodtakesthepiezoelectriceffectofPCsintoaccount,inwhichperiodicboundaryconditionsareusedtodecreasememory/timeconsumptionandtheperfectlymatchedlayerboundaryconditionsareadoptedastheSAWabsorberstoattenuateartificialreflections.TwoSAWdelaylinesareestabhshedwith/withoutpiezoelectricPCslocatedbetweeninterdigitaltransducers.Byremovingseveralechoeswithwindowgatingfunctionintimedomain,delaylinestransmissionfunctionisachieved.ThePCs’transmissionfunctionsandbandgapsareobtainedbycomparingtheminthesetwodelaylines.WhenAluminum/128°YX-LiNbO3isadoptedasscatterandsubstratematerial,thePCs’bandgapiscalculatedbythisFDTDmethodandCOMSOLrespectively.ResultsshowthatcomputationalresultsofFDTDagreewellwithexperimentalresultsandarebetterthanthatofCOMSOL.

简介：Wedemonstratebinaryphaseshiftkeying(BPSK)modulationusingasiliconMach–Zehndermodulatorwithaπ-phase-shiftvoltage(Vπ)of-4.5V.Thesingle-drivepush–pulltravelingwaveelectrodehasbeenoptimizedusingnumericalsimulationswitha3dBelectro-opticbandwidthof35GHz.The32Gb/sBPSKconstellationdiagramismeasuredwithanerrorvectormagnitudeof18.9%.

简介：Inthispaper,weinvestigatethetravelingwavesolutionsforthenonlineardispersiveequation,Korteweg-deVriesZakharov–Kuznetsov(KdV-ZK)equationandcomplexcoupledKdVsystembyusingextendedsimplestequationmethod,andthenderivethehyperbolicfunctionsolutionsincludesolitonsolutions,trigonometricfunctionsolutionsincludeperiodicsolutionswithspecialvaluesfordoubleparametersandrationalsolutions.Thepropertiesofsuchsolutionsareshownbyfigures.Theresultsshowthatthismethodisaneffectiveandapowerfultoolforhandlingthesolutionsofnonlinearpartialdifferentialequations(NLEEs)inmathematicalphysics.

简介：尽管科学家因为石墨烯无与伦比的属性而对其青睐有加，但迄今为止，其实际应用仍然乏善可陈。不过，瑞士洛桑联邦理工学院生物纳米系统实验室和西班牙光子科学研究所的科学家们在最新一期的《科学》杂志上宣称，他们利用石墨烯独特的光学和电子学属性，研制出了一种具有超高灵敏度的分子传感器，可以探测蛋白质或药物小分子的详细信息。

简介：根据实际应用需求,设计了一种X波段宽带圆波导耦合器。通过理论计算与数值模拟优化,实现频率9.3GHz时,耦合度约为一71.2dB;频率范围为9～10GHz时,耦合曲线平坦度小于0.3dB,可显著降低微波功率测量不确定度。为了提高耦合器的功率容量,对结构进行了改进,在耦合孔处进行了倒圆角处理。倒圆角半径为1mm时,耦合孔最高场强降低了52%,功率容量得到提高。