简介：BaotouMotorWorksisastate-runmotorpro-ducerinChina.TheinventionofNd-Fe-Bperma-nentmagnethashelpedtheplantsuccessfullydevel-opZYNseriesdcmotorswhichpossesstheadvan-tagesofreducedvolume,lightweightandhigheffi-ciency.Since1991,thedcmotorhasbeenexten-sivelyappliedtometallurgicalmachinestotaketheplaceofthetraditionalZ3seriesmotors.

简介：Thisworkpresentsanumericalsimulationoftheflowfieldinaliquidpropellantrocketenginechamberandexitnozzleusingtechniquestoallowtheresultstobetakenasstartingpointsfordesigningthosepropulsivesystems.ThiswasdoneusingaFiniteVolumemethodsimulatingthedifferentflowregineswhichusuallytakeplaceinthosesystems.Astheflowfieldhasregionsrangingfromthelowsubsonictothesupersonicregimes,thenumericalcodeused,initiallydevelopedforcompressibleflowsonly,wasmodifiedtoworkproficientlyinthewholevelocityrange.ItiswellknownthatcodeshavebeendevelopedinCFD,foreithercompressibleofincompressibleflows,thejointtreatmentofbothtogetherbeingcomplexeventoday,giventhesmallnumberofreferencesavailableinthisarea.Hereanexistingcodeforcompressibleflowwasusedandprimitivevariables,thepressure,theCartesiancomponentsofthevelocityandthetemperatureinsteadoftheconservedvariableswereintroducedintheEulerandNavier-Stokesequations.ThiswasdonetopermitthetreatmentatanyMachnumber.Unstructuredmesheswithadaptiverefinementswereemployedhere.Theconvectivetermsweretreatedwithupwindfirstandsecondordermethods.ThenumericalstabilitywaskeptwithartificialdissipationandinthespatialcoverageoneusedafivestageRunge-KuttaschemefortheFluidMechanicsandtheVODE(ValueofOrdinaryDifferentialEquations)schemealongwiththeChemkinIIinthechemicalreactingsolution.Duringthedevelopmentofthiscodesimulatingtheflowinarocketengine,comparisontestsweremadewithseveraldifferenttypesofinternalandexternalflows,atdifferentvelocities,seekingtoestablishtheconfidencelevelofthetechniquesbeingused.ThesecomparisonsweredonewithexistingtheoreticalresultsandwithothercodesalreadyvalidatedandwellacceptedbytheCFDcommunity.

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简介：Thisstudypresentedanoff-lineidentificationmethodofinductionmotor(IM)parameters.Beforestartup,theinverterdriveperformedautomaticallyamodifiedDCtest,alocked-rotortest,ano-loadtestandastep-voltagetesttoidentifyalltheparametersofaninductionmotor.Nomanualoperationandspeedsignalswererequiredintheprocess.Inordertoobtaineffectivemessagesandimprovetheaccuracyofidentification,thediscretefastFouriertransform(DFFT)andtheleast-squareswereusedtoprocessthesignalsofcurrentsandvoltages.Aphase-voltagemeasuringmethodformotorswasalsoproposed,whichmeasureddirectlytheactualconductingtimeofthreeupperswitchesintheinverterwithoutneedforadead-timecompensator.Thevalidity,reliabilityandaccuracyofthepresentedmethodshavebeenverifiedbytheexperimentsonaVSI-fedIMdrivesystem.

简介：Thispaperdealswithon-linestateandparameterestimationofareasonablylargeclassofnonlinearcontinuous-timesystemsusingastep-by-stepslidingmodeobserverapproach.Themethodproposedcanalsobeusedforadaptationtoparametersthatvarywithtime.Theotherinterestingfeatureofthemethodisthatitiseasilyimplementableinreal-time.Theefficiencyofthistechniqueisdemonstratedviatheon-lineestimationoftheelectricalparametersandrotorfluxofaninductionmotor.Thisapplicationisbasedonthestandardmodeloftheinductionmotorexpressedinrotorcoordinateswiththestatorcurrentandvoltageaswellastherotorspeedassumedtobemeasurable.Real-timeimplementationresultsarethenreportedandtheabilityofthealgorithmtorapidlyestimatethemotorparametersisdemonstrated.Theseresultsshowtherobustnessofthisapproachwithrespecttomeasurementnoise,discretizationeffects,parameteruncertaintiesandmodelinginaccuracies.Comparisonsbetweentheresultsobtainedandthoseoftheclassicalrecursiveleastsquarealgorithmarealsopresented.Thereal-timeimplementationresultsshowthattheproposedalgorithmgivesbetterperformancethantherecursiveleastsquaremethodintermsoftheconvergencerateandtherobustnesswithrespecttomeasurementnoise.

简介：ThehulbarparalysisofupperrnotorneuronsisacommonseniIedisease.lnrecentycars.weselectLianquan(CV23)asachiefpointincomhinationwithJinjin(EX-HNl2).Yuye(FX-HN13)andZhaohai(KI6)andemployuniformreinforcing-reducingmanipuIationtotreat280patients.Theresultsshowthatatotaleffectivcrateis55.71％.Thepossiblemechanismsaredis-cussedpreliminarilyinthcpresentpaper.

简介：WeproposeaBPNNbasedadaptiveslidingmodecontrolschemeforspeedtrackingofaDCmotorwithunknownsystemnonlinearities.Theinput-outputlinearizationtechniqueisusedtocancelthenonlinearities,andoutputoftheBPNNisincorporatedintothecontrollerintheproposedscheme.ItisshownthattherotorspeedofaDCmotorcanfollowanyarbitrarilyselectedtrajectoriesundervariableloadtorque.Thentheapplicationoftheapproachistestedviacomesimulations.

简介：ThispaperpresentsasimpleandrobustspeedcontrolschemeofPermanentMagnetSynchronousMotor(PMSM).Itistoachieveaccuratecontrolpeffommancemthepresenceofloadtorqueandplantparametervariation.Arobustdisturbancecancellationfeedforwardcontrollerisusedtoestimatethetorquedisturbance.ThesimpleandpracticalcontrolschemeiseasilyimplementedonaPMSMdriverusingaTMS320LF2407DSP.Theeffectivenessoftheproposedrobustspeedcontrolapproachisdemonstratedbysimulationandexperimentalresults.

简介：WiththebackgroundofthecontrolofadditionalmechanicalforcedroplettransferinMIG/MAGwelding,regardingtheACservomotorascore,anoveloscillatingwirefeedingsystemhasbeendevelopedwithexcellentperformancesofcontrolanddynamicaccelerationwhichistested.Systemconstitutionandoperationprincipleareintroducedinthispaper.Influencesofparametersondynamicaccelerationperformanceareanalyzedanddiscussedemphatically,suchasoscillatingfrequency,oscillatingamplitudeanddraw-backspeed.Experimentalresultindicatesthataccordingtothetechniqueofweldingcontrol,thenovelwirefeedingsystemrespondsrapidlytovariouskindsofcontrolordersofwirefeedinganddraw-back,andrealizesflexiblecontrolofweldingwireaxialmovement,includingdynamicshifting,oscillatingandsoon.

简介：Thegoalsofthispaperaretwofold:wedescribecommonfeaturesindatasetsfrommotorvehicleinsurancecompaniesandweinvestigateageneralstrategywhichexploitstheknowledgeofsuchfeatusres.Theresultsofthestrategyareabasistodevelopinsurancetariffs.Weuseanonparametricapproachbasedonacombinationofkernellogisticregressionandε-supportvectorregressionwhichbothhavegoodrobustnessproperties.Thestrategyisappliedtoadatasetfrommotorvehicleinsurancecompanies.

简介：1.IntroductionItiswellknownthattheefficiencyandpowerfactorofthesolid-rotorinductionmotorarelowerthanthoseofthecagerotorin-ductionmotorduetolargerleakagereactance.Therefore,conduct-ingendringsareoftenfittedtorotorendstoimprovemotorper-formance.Mostoftheanalysesonthesolid-rotorinductionmotorwithendringshaveassumedthatthemotorisofinfinitecorelengthandtangentialcurrentintherotortobenegligible.

简介：Objective:Tobetterunderstandthecharacteristicsoftheneurogenicmotorevokedpotential(NMEP)beforeandafteracutespinalcordinjury.Methods:WerecordedandcharacterizedthespinalcordNMEPfrom48normalratsandfrom38ratswithspinalcordhemisectionlesion.SpinalcordNMEPswereelicitedbyapplyingarangeofcurrentintensitieswithbipolarmicroelectrodestimulitotheC4cordsegmentandrecordingtheresponsesfromsciaticnerveswithbipolarmicroelectrodesplacedintheneurilemma.Results:Theevokedpotentialsconsistedofthreestableandreproduciblenegativeandthreepositivepeaks.Themean±SDlatenciesofN1were2.89±0.22msontherightsideand2.89±0.24msontheleftside.Themeanconductionvelocitywas47.9m/s.Themean±SDamplitudesofN1were3.61±2.10μVontherightsideand3.83±2.32μVontheleftside.TheamplitudesofN1weresignificantlydifferentamongtheeightstimulusintensitygroups(rightside:F=2.22,df=7201,P=0.03;leftside:f=2.11,df=7206,P=0.04).Theamplitudewaslargestwhenthestimulusintensitywas1.1-2.5mA.ThelatenciesofN1werenotsignificantlydifferentamongtheeightstimulusintensitygroups(rightside:F=0.40,df=7201,P=0.9;leftside:F=1.20,df=7206,P=0.3).TheamplitudesandlatenciesofN2,N3werenotsignificantlydifferentamongtheeightstimulusintensitygroups.Therewerenosignificantchangesinlatencyandamplitudebetweentheleftandtherightsidenerveresponses.Thirty-eightratsundewentT9cordrightsidehemisection.Amongthem,20(53%),30(79%),and32(84%)ratscouldnotberecordedincorrespondingtoN1,N2,andN3,respectively,intheright-sidesciaticnerves;and13(79%),18(47%),and21(55%),incorrespondingtoN1,N2,andN3intheleft-sidesciaticnerves.Thelatencywassignificantlydelayedonthebothrightandleftsides.TheamplitudeN1wassignificantlydepressedonthebothsides,withN3significantlydepressedontherightsideandN2notsignificantlydepressed.Conclusions:TheamplitudeofNissignificantlydiffere

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简介：Objective:Toobservetheeffectofacupunctureoncerebralglucosemetabolisminstrokepatients.Methods:Changesofcerebralglucosemetabolismbeforeandafteracupuncturestimulationwereobservedinsixcasesofstrokepatientsbyusingpositronemissiontomography(PET)scanner.Electroacupuncture(EA,4Hz,continuouswavesanddurationof20min)wasappliedtoBaihui(百会GV20)andrightQubin(曲鬓GB7).18Fluorinedeoxyglucose(18FDG),adeveloper(radioactiveformofglucose)forshowingthelevelsofthebrainfunctionalactivitywasgiventothepatientsintravenously.SPMsoftwarewasusedtodealwiththedataofeachpixelpointbyunilateralt-test(Ts:P=0.05),then,theregionsshowingincrease/decreaseoftheglucosemetabolismwereobtained.Results:Afteracupuncturestimulation,significantincreaseofglucosemetabolismwasfoundtobeinthefirstsomaticmotorcorticalregion(MI),supplementarymotorarea(SMA),premotorarea(PMC),andthesuperiorparietallobule(LPs)onthehealthysideofthebrain;whilethedecreaseofglucosemetabolismfoundinMI,PMCandLPsonthefocusside.Inadditiontothecerebralregionsrelatedtothemotorfunction,changesofglucosemetabolismwerealsofoundintheparietallobuleandbasalganglionarea,centralparietalgyrus,superiorparietalgyrus,putamen,cerebellum,etc..Conclusion:AcupunctureofQubin(GB7)andBaihui(GV20)canactivatemotor-relatedcerebralstructuresinthebilateralcerebralhemisphereandinduceexcitementreactionofthepotentiallycorrelativemotorareasoastocompensateorassisttheinjuredmotorareatoplayaroleinimprovingmotorfunctioninstrokepatients.

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简介：Injuryofankleisthemostcommoninathleticinjury.Becauseofanatomicparticu-larityofanklejoint,i.e.lateralmalleolusislongandthinandislocatedattheposteriorandlowerthanmedialmalleolus.Themedialmalleolusisbroadandflatandislocatedattheanterior.Lateralligamentisthinnerandweakerthanmedialligamentandthemusclegroupssupportingstrephexopodiaisfarinferi-ortothemusclegroupssupportingstrephenopodiainstrength,injuryofanklejointhappensmoreatinversionsprainandin-juryofanteriortalofibularligamentisinducedoften.Thus,rapidandeffectivetreatmentofanteriortalofibularligamentinjurycanelevatebetterathleticsofsportsman.Wheneverthediseasehappenedinstudentstoexercise,theauthorsoftenusedacupunctureofQiuxu（GB40）-through-Zhaohai（KI6）pointwithstrongstimulativemanipulation,whichcouldrelievemoreremakedlypainoftheanklejointcausedbyanteriortalofibularligamentinjuryasre-portedinthe