简介：在这研究，一个新数学模型被开发二部分创作了，包括为模仿近的差错地面运动的主导的速度脉搏的泛音和多项式表情。基于建议速度功能，为扎根的加速的相应表情和排水量时间历史也被导出。建议模型然后在下一代变细(NGA)工程图书馆用在差错地面运动附近像脉搏的选择的一些被适合。新模型简单处于良好的竟技状态而且与精确的高水平在差错记录附近模仿实际速度的长时期的部分不仅。建议基于模型的有弹性的反应系列与在脉搏的占优势的频率的邻居的近的差错记录兼容，这被显示出。结果显示建议模型足够地模仿时间历史的部件。最后，建议脉搏的精力与实际记录的精力相比证实相容性。

简介：Theenergytransmissionofthelongmicrowavepulseforthefrequencyof2.45GHzand5.8GHzisstudiedbyusingtheelectronfluidmodel,wheretheratecoefficientsarededucedfromtheBoltzmannequationsolvernamedBOLSIG+.Thebreakdownthresholdsfordifferentairpressuresandincidentpulseparametersarepredicted,whichshowgoodagreementwiththeexperimentaldata.Belowthebreakdownthreshold,thetransmittedpulseenergyisproportionaltothesquareoftheincidentelectricfieldamplitude.Whentheincidentelectricfieldamplitudehigherthanthebreakdownthresholdincreases,thetransmittedpulseenergydecreasesmonotonouslyatahighairpressure,whileatalowairpressureitfirstdecreasesandthenincreases.Wealsocomparethepulseenergytransmissionforthefrequencyof2.45GHzwiththecaseof5.8GHz.

简介：Thepulseamplificationinthedispersion-decreasingfiber(DDF)isinvestigatedviasymboliccomputationtosolvethevariable-coefficienthigher-ordernonlinearSchr(o|¨)dingerequationwiththeeffectsofthird-orderdispersion,self-steepening,andstimulatedRamanscattering.Theanalyticone-solitonsolutionofthismodelisobtainedwithasetofparametricconditions.Basedonthissolution,thefundamentalsolitonisshowntobeamplifiedintheDDF.ThecomparisonoftheamplitudeofpulsesfordifferentdispersionprofilesoftheDDFisalsoperformedthroughthegraphicalanalysis.Theresultsofthispaperwouldbeofcertainvaluetothestudyofsignalamplificationandpulsecompression.

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简介：Muonsproducedbyashortpulselasercanserveasanewtypeofmuonsourcehavingpotentialadvantagesofhighintensity,smallsourceemittance,shortpulsedurationandlowcost.Tovalidateitinexperiments,asuitablemuondiagnosticssystemisneededsincehighmuonfluxgeneratedbyashortpulselasershotisalwaysaccompaniedbyhighradiationbackground,whichisquitedifferentfromcasesingeneralmuonresearches.Adetectionsystemisproposedtodistinguishmuonsignalsfromradiationbackgroundbymeasuringthemuonlifetime.Itisbasedonthescintillatordetectorwithwaterandleadshields,inwhichwaterisusedtoadjustenergiesofmuonsstoppedinthescintillatorandleadtoagainstradiationbackground.AGeant4simulationontheperformanceofthedetectionsystemshowsthatefficiencyupto52%couldbearrivedforlow-energymuonsaround200MeVandthisefficiencydecreasesto14%forhigh-energymuonsabove1000MeV.Thesimulationalsoshowsthatthemuonlifetimecanbederivedproperlybymeasuringattenuationofthescintillalightofelectronsfrommuondecaysinsidethescintillatordetector.

简介：Theoxidativesplittingprocessofcis-syn1,3-dimethyluracilcyclobutanedimer(DMUD)inaqueoussolutionwasinvestigatedusingpulseradiolysistechnique.TheresultsindicatedthatDMUDcanbesplittedinto1,3-dimethyluracil(DMU)byOHradicals(OH)andBr2radicalanions(Br2^-),butnotbyazideradicals(N3^).TheoxidativemechanismsthatanH-abstractedfromDMUDforOHoxidativesplittingandanelectrontransferfromDMUDtoBr2-,weresuggested.Relatedkineticparametersweredetermined.

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简介：ThePMD-inducedpulsebroadeningmaycausethedegradationofreceiversensitivityandhasnegativeeffectsonthepowerspectrumofreceivedsignals.TheexpressionsofPMD-inducedpulsebroadeningeffectsonreceiversensitivityarederivedbasedontheconceptofmeansquarepulsewidth.TheeffectsofPMDonthespectrumofreceivedpowerareanalyzedindetail.Finally,theschemeisdiscussedwithwhichthepowerofacertainfrequencycomponentisextractedasafeedbackcontrolsignalinaPMDcompensationsystem.

简介：BackgroundPulseoximetryscreening(POS)hasbeenproposedasaneffective,noninvasive,inexpensivetoolallowingearlierdiagnosisofcriticalcongenitalheartdisease(CCHD).However,mostneonatesaredischargedfromthehospitalwithoutthisevaluationinChina.ThisstudyaimedatassessingthefeasibilityofPOSfornewbornsindetectingCCHDinthedepartmentofobstetricsandneonatalintensivecareunit(NICU).MethodsPOSwasperformedin355neonatesborninthedepartmentofobstetricsoradmittedtotheNICUbetweenJanuary2015andJune2015.Theseneonatesweredividedintonormalgroup,mildcongenitalheartdiseasegroup(MCHD)andCCHDgroup,accordingtotheresultofechocardiographyorcomputerizedtomography(CT).Thegestationalage,birthweightandarterialoxygensaturation(SpO_2)werecomparedamongthethreegroups.TheSpO_2valueanddiagnosistimeoftheCCHDcaseswereclassifiedandanalyzed.ResultsTheprematurebirthandlowbirthweightwerethehighriskfactorsofmildcongenitalheartdisease.Therewasnodifference(P>0.05)inSpO_2betweentheMCHDgroupandthenormalgroup.SignificantdifferenceintheSpO_2appearedbetweentheCCHDgroupandthenormalgroup(P<0.05).CombinationofPOSandclinicalexaminationcanreducethemissingdiagnosisrateinscreeningforCCHD.ConclusionsPOSincursverylowcostandriskofharmandisnotrequiredforspecialtraining,therefore,aneffectivewaytoidentifyCCHDinneonates.

简介：ApyrotechnicallypumpedNdglasslaserisdemonstratedbytheuseofpyrotechnicflashlampscomposedofseveralchemicalmaterialsarrangedinastableplaneconcaveresonatorcavity.Theflashlampwasmadeofchemicalmixturewithoxidant,fuel,andbinder.TheemissionspectrumofpyrotechnicflamecoveredmostoftheabsorptionbandsofNd~(3+)inphosphateglass.Under4.56-gchemicalmixturepumping,longpulseoutputpowerofabout5.5Wwasachieved.

简介：AkindofarchitectureofTime-to-DigitalConverter(TDC)forUltra-WideBand(UWB)applicationispresented.TheproposedTDCisbasedonpulseshrinking,andimplementedinaFieldProgrammableGateArray(FPGA)device.ThepulseshrinkingisrealizedinaloopcontainingtwoProgrammableDelayLines(PDLs)oratwo-channelPDL.Oneline(channel)delaystherisingedgeandtheotherline(channel)delaysthefallingedgeofacirculatingpulse.DelayresolutionofPDLisconvertedintoadigitaloutputcodeunderknownconditionsofpulsewidth.Thisdelayresolutionmeasurementmechanismisdifferentfromtheconventionaltimeintervalmeasurementmechanismbasedonpulseshrinkingofconversionofunknownpulsewidthintoadigitaloutputcode.Thismechanismautomaticallyavoidstheinfluenceofunwantedpulseshrinkingbyanycircuitelementapartfromthelines.TheachievedrelativeerrorsforfourPDLsarewithin0.80%–1.60%.

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简介：TheapplicationoftherandombinaryphasecodedsignalintheCWradarsystemhasbeenlimitedbythedifficultytoisolatethetransmissionandreceptionsignal.Inordertomakeuseoftherandombinaryphasecodedsignal,therandombinaryphasecodedpulseradar(RBPC-PR)systemhasbeenstudied.First,theaverageambiguityfunction(AAF)oftheRBPC-PRsignalhasbeenanalyzed.Then,astatisticalmethodofreducingtherangesidelobe(RSL)ispresented.Finally,asignalprocessingschemeoftheRBPC-PRisdevdoped.Thesimulationresultsshowthatbyusingthescheme,thejammingimmunityofthesystem,theresolutionandaccuracyofdistanceandvelocityhavebeenimproved,andthedistanceandvelocityvaguenesscausedbyperiodscanalsoberemoved.TheRSLcanbereducedover30dBbythestatisticalaveragemethod,thustheprobabilityambiguitycausedbyrandomnoisecanbeavoided.

简介：AnovelpancakeRogowskicoilwithoutmagneticcoreisintroducedinthispaper.Owingtoitsspecialpancakewindingstructure,thecoilisoflowself-resistanceandhighself-inductance,andthushasexcellentlowfrequencycharacteristicintheself-integralmode.Moreover,becauseofitsuniqueinstallationmethod,thecoilhasaflexiblesensitivityandcanbeappliedundersituationswheretoroidalair-coreRogowskicoilsorprintedaircuitboard(PCB)coilsarenotavailable.TheparametersandperformanceofthepancakeRogowskicoilarepresented,andtheprincipleofshieldingisgiven.Measurementsofsteppulsecurrentandoscillatingpulsecurrentbythecoilarestudiedexperimentallytoillustrateitsgoodlinearity,reliableandflexiblesensitivityandexcellentfrequencycharacteristic,especiallyitsadvantageinlowfrequencycharacteristic.ThepancakeRogowskicoilcanbedesignedtoassumeround,squareorrectangleshape,andhasthusbroadprospectsinitsapplicationtothecurrentmeasurementinsuchareasasplasmaphysicsandpulsedpowertechnology.

简介：Inourpreviouswork,aplasmaapproachforsingleattosecondpulse(AP)generationwasproposed.Afew-cyclerelativisticcircularlypolarizedlaserpulsewillinduceasingledrasticoscillationofplasmaboundary,fromwhichhigh-orderharmonicsandfurthermoreanultra-intensesingleAPcanbegeneratednaturallyafteritisreflected.Analyticalmodelandsimulationsbothdemonstratethattheprocessismostlyefficientasthepulsedurationisclosetotheplasmarespondingtime.Theeffectsofplasmadensityrampareanalyzedhere,suggestingthattheproposalisstillquiteefficientwithappropriatedensitygradientintheramp.Atlast,acombinedapproachisemployedtoobtainsingleAPwith30fsincidentlaser.Therelativelylarge-durationpulseisfirstlyshortenedbyadensitydroppingthinfoil,andthenreflectedfromanoverdenseplasmatarget.One-dimensionalsimulationshowsthata600assinglelightpulseisgeneratedwithpeakintensityof3×1020W/cm2.

简介：Theconceptofhealthmonitoringisakeyaspectofthefieldofmedicinethathasbeenpracticedforalongtime.Acommonlyuseddiagnosticandhealthmonitoringpracticeispulsediagnosis,whichcanbetracedbackapproximatelyfivethousandyearsintherecordedhistoryofChina.Withadvancesinthedevelopmentofmodemtechnology,theconceptofhealthmonitoringofavarietyofengineeringstructuresinseveralapplicationshasbeguntoattractwidespreadattention.Ofparticularinterestinthisstudyisthehealthmonitoringofcivilstructures.Itseemsnatural,andevenbeneficial,thatthesetwohealth-monitoringmethods,oneasappliestothehumanbodyandtheothertocivilstructures,shouldbeanalyzedandcompared.Inthispaper,thebasicconceptsandtheoriesofthetwomonitoringmethodsarefirstdiscussed.Similaritiesarethensummarizedandcommentedupon.Itishopedthatthiscorrelationanalysismayhelpprovidestructuralengineerswithsomeinsightsintotheintrinsicconceptofusingpulsediagnosisinhumanhealthmonitoring,whichmaybeofsomebenefitinthedevelopmentofmodernstructuralhealthmonitoringmethods.

简介：AjammingsuppressionmethodbasedonpolarizationsignaldetectionisproposedundercommonrangeandvelocitycheatingjammingforpulseDopplerradar.Onthebasisoftheseparationofthetargetandthejamming,therangeandvelocitytrackonthetruetargetarerealized.FirstlythesignalprocessingmodelofthefullpolarizationpulseDopplerradarisintroduced.Secondlythemethodofcorrecttargetseparationisdiscussed,whichisthetwicedetectionsofenergyandpolarizationstateonthetwodimensionresolutioncellsofrangeandvelocityoftheradarecho.Finallythesimulationsareperformedandtheresultsprovethevalidity.What'smore,multiplerangeandvelocitycheatingjammingcanbesuppressedatthesametimeifthetargetandthejammingaredifferentinthepolarizationdomain.