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简介：Recursiveformulationshavesignificantlyhelpedinachievingreal-timecomputationsandmodel-basedcontrollaws.Therecursivedynamicssimulator(ReDySim)isaMATLAB-basedrecursivesolverfordynamicanalysisofmultibodysystems.ReDySimdelvesuponthedecouplednaturalorthogonalcomplementapproachoriginallydevelopedforserial-chainmanipulators.Incomparisontothecommerciallyavailablesoftware,dynamicanalysesinReDySimcanbeperformedwithoutcreatingsolidmodel.TheinputparametersarespecifiedinMATLABenvironment.ReDySimhascapabilitytoincorporateanycontrolalgorithmwithutmostease.Inthiswork,thecapabilitiesofReDySimforsolvingopen-loopandclosed-loopsystemsareshownbyexamplesofroboticgripper,KUKAKR5industrialmanipulatorandfour-barmechanism.ReDySimcanbedownloadedforfreefromhttp://www.redysim.co.nrandcanbeusedalmostinstantly.

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

简介：Thispaperaimstodesignpunchingdieofthestatorandrotor.Byanalyzingandcomparing,wedeterminethebetterprocessingprogram.Notonlytoensuretheprecisionanddimensionalrequirements,butalsotoimproveefficiency.Throughdetailedanalysisoftheprocess,thispaperdeterminesthestructureoftwocompositemolds.Thedimensionsofitsconvexandconcavedieedgesizeandotherpartsarecalculatedandchecked.Finallythispapercompletesthedesignoftwomolds.

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简介：Inthispapertheprocessofknowledgeaccumulationforaparticulartechnologyisstudied.Twocountries,saythetechnologyfollowerandthetechnologyfrontier,areconsidered.Thefrontier’sknowledgegrowthisdeterminedbyitsR&Deffortsonthetechnology.ThelevelofknowledgestockforthefollowercountryisaugmentedbyitsR&Dactivitiesforthetechnologyandabsorbingsomeoftheexternalknowledgethroughspilloverfromthefrontier.Theextenttowhichthefollowerisabletoexploittheexternalknowledgedependsontechnologicalgap,absorptivecapacity,absorptiontimeanddegreeofspillover.Newconceptssuchasnaturalandenhanceddegreeofspillover,backgroundandinnovativeknowledgeandabsorptionspeedareintroducedinthepresentworktodeeplyexploretheprocessofknowledgespillover.ThefactorsinfluencingtheknowledgedevelopmentinthelongtermaresimultaneouslystudiedinanintegratedstructureprovidedbytheSystemDynamicsapproach.Thisframeworkshowstheresponsestothechangesandprovidesthebasisforexaminingtheinteractionsamongthevariablesovertime.

简介：Nonlinearmetailogenicdynamicsisoneofthodifficultprob1emsthatcommonlyfacemoderncom-plcxscicnces.TheRussianfamousmetallogenjstA.D.Shcbeglov(1988)paidattentiontotheprob1emofnonlin-earmctal1ogenyandproposedthcconceptofnonlinearmcta11ogeny.HepointedoutthatthercjSane-cessityofamoredetailedandcomprchensive

简介：正弦电场驾驶的一个蛋白质马达系统被调查。Thesignal-to-noise比率(SNR)在断热的限制被导出。随机的回声的现象被作出对有利的裁决这个蛋白质马达系统。

简介：题目：一种多振子超声电机的设计目的：对超声电机而言，当多个压电振子并联时，由于以同一设计方案制作的电机振子往往具有不同的动态特性，因此会使得多振子电机的效率有所下降。即多振子电机工作的关键是如何使多个振子协同一致地驱动转子。为提高集成型多振子电机的效率和简化电机结构，提出一种构造贴片式多振子旋转超声电机的方法。创新点：1．提出圆周面内驱动的概念，发展已有的面内驱动概念（x-y面）；2．提出一种模态转换方法，通过多个振子弯曲振动的叠加形成设计电机的扭转振动；3．电机工作时，不仅各个振子处于共振状态，而且连接而成的定子同样处于共振状态，有利于提高电机的效率；4．验证多振子同步驱动的机理。方法：1．振子采用贴片式结构，由极化方向沿厚度方向的压电陶瓷和金属基体粘结而成；与使用兰杰文振子相比，使用贴片式振子易于简化电机的结构。2．各个振子首尾相连形成电机的定子，既可用于构造直线电机，又可转换成旋转电机。3．通过有限元方法对不同振子数构成的电机定子进行性能比较，并且分析设计电机的驱动机理；此外，通过仿真分析确定电机的最优尺寸。4．根据设计结果，加工原理样机，并且对加工的样机进行实验研究，探讨设计方法的可行性。结论：1．根据仿真分析结果，最终加工的电机定子包含5个振子。2．定子中各个振子的振动特性完全相同，振子同步工作。3．样机定子的内径为28mm，外径为35mm，高为30min；测得定子的纵振和扭转频率分别为44．42kHz和43．83kHz；当激励电压的频率为43．9kHz、峰值为100V时，电机的空载转速为45r／min，堵转力矩为0．3N·m，最大效率约为30％。4．本文所设计的电机，是一种多振子并行驱动的整体式电机，具有结构紧凑和多�

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.

简介：摘要： Motor-Cad是十分强大的电机设计分析工具。本论文基于Motor-Cad设计了某功率型号的外转子直驱式轮毂电机并对其性能进行了研究，电机采用永磁同步电动机，相对于传统的车用驱动电机，这种电机具有高效、高功率密度、结构简单紧凑等一系列优点，特别适合作为车用电机使用，对其性能的研究也表明，设计的电机能够完全满足电动车使用要求。

简介：Theorganizationofthecanonicalgeneticcodeneedstobethoroughlyilluminated.Herewereorderthefournucleotides-adenine,thymine,guanineandcytosine-accordingtotheiremergenceinevolution,andapplytheorganizationalrulestodevisinganalgebraicrepresentationforthecanonicalgeneticcode.Underaframeworkofthedevisedcode,wequantifycodonandaminoacidusagesfromalargecollectionof917prokaryoticgenomesequences,andassociatetheusageswithitsintrinsicstructureandclassificationschemesaswellasaminoacidphysicochemicalproperties.Ourresultsshowthatthealgebraicrepresentationofthecodeisstructurallyequivalenttoacontent-centricorganizationofthecodeandthatcodonandaminoacidusagesunderdifferentclassificationschemeswerecorrelatedcloselywithGCcontent,implyingasetofrulesgoverningcompositiondynamicsacrossawidevarietyofprokaryoticgenomesequences.Theseresultsalsoindicatethatcodonsandaminoacidsarenotrandomlyallocatedinthecode,wherethesix-folddegeneratecodonsandtheiraminoacidshaveimportantbalancingrolesforerrorminimization.Therefore,thecontent-centriccodeisofgreatusefulnessindecipheringitshithertounknownregularitiesaswellasthedynamicsofnucleotide,codon,andaminoacidcompositions.

简介：Intherepresentationofnaturalandsocialphenomena,thereexistnotonlyordinaryorpartialdiferentialequationswhichareindependentofthepaststatesanddeterminedsolelybythepresentstates,butalsotimedelaydiferentialequationswhicharerelatedtosomeof更多还原

简介：Anewflowtheoryisestablishedthroughtheobjectivityrequirementonthefluiddynamics.Itwasknownthatinhomogeneousfluidmotiongaverisetoviscousforcewhiletheselectionofobserversondifferentspace-timepointswouldchangesuchaninhomogeneouscharacter.Therefore,whentheviscousforcewasconsideredasanobjectiveexistenceforeigntotheselectionofobservers,theforminvariancesofviscousforceandmomentumequationunderlocalrotationtransformationrequiredanewdynamicfield,namelythevortexfieldtobeintroduced.ThenthedynamicalequationsofallflowfieldswereobtainedthroughconstructingtheLagrangiandensityoffluidsystemandusingthevariationalapproachofenergy.

简介：日本家电制造企业将公示家电税前价格；2014年全球液晶电视出货量将增至2．13亿台；11月美国家电出货量同比增长18％

简介：Thispaperstudiestheiterationsofholomorphicself-mapswhichhavenonwanderingpointsovergeneralpseudoconvexdomainsisC^2.TheauthorsgiveespeciallyaDenjoy-Wolff-typetheoremonpseudoconvexdomainswithreal-analyticboundaries,orevenmoregeneral,ondorpainsoffinitetype.

简介：TherelationshipbetweendissolutionrateandpHisdeterminedbycarryingoutdynamicexperimentsofhedenbergiteandgrossularitedissolution.Thedissolutionreactionequationsareestablished.Thedissolutionpro-cessesoftwomineralsaresimulatedbyusingthetheoryofmulti-phaseandmulti-componentchemicalequilibrium.Theresultsbringlighttothemechanismofdissolutionprocesses.Duetoincongruentdissolutionoftwomineralswhenthedissolutionprocessesreachametastablesupersaturationcriticalpointnewmetastablemineralscanbeformedinthesystem.TheexperimentsshowedthatdissolutionofgrossulariteandhedenbergiteconsumesH~+andthenmakespHvalueofsolutionhigh.Inturn,precipitationofmetastablemineralsmakespHvaluelow.Precipitationofmetastablemineralshasacatalyticeffectfordisso-lutionofreactingmineralsinspecialtime.PrecipitationanddissolutioncarriedoutalternatelyinthesystemanditcausesperiodicoscillationofpHvalueswithreactingtime.Thisisthe