简介：Inthispaper,withPoincare’sformalism,andanindirectmethod,thecanonicalformsofthegeneralizedequationsofmotionduetoNielsenandCenovofaholonomicdynamicalsysteminthevelocity-phasespaceandtheacenleration-phasespaceareobtainedintermsofthePoincareparameters.

简介：ThesolutionsofGreen'sfunctionaresignificantforsimplificationofproblemonatwo-phasesaturatedmedium.UsingtransformationofaxisymmetriccylindricalcoordinateandSommerfeld'sintegral,superpositionoftheinfluencefieldonafreesurface,authorsobtainedthesolutionsofatwo-phasesaturatedmediumsubjectedtoaconcentratedforceonthesemi-space.

简介：Thediscretizationsizeislimitedbythesamplingtheorem,andthelimitisonehalfofthewavelengthofthehighestfrequencyoftheproblem.However,onehalfofthewavelengthisanidealvalue.Ingeneral,thediscretizationsizethatcanensuretheaccuracyofthesimulationismuchsmallerthanthisvalueinthetraditionalfiniteelementmethod.Thepossiblereasonofthisphenomenonisanalyzedinthispaper,andanefficientmethodisgiventoimprovethesimulationaccuracy.

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简介：Byusingthefundamentalequationsofaxisymmetricshallowshellsofrevolution,thenonlinearbendingofashallowcorrugatedshellwithtaperunderarbitraryloadhasbeeninvestigated.ThenonlinearboundaryvalueproblemofthecorrugatedshellwasreducedtothenonlinearintegralequationsbyusingthemethodofGreen'sfunction.Tosolvetheintegralequations,expansionmethodwasusedtoobtainGreen'sfunction.ThentheintegralequationswerereducedtotheformwithdegeneratecorebyexpandingGreen'sfunctionasseriesofcharacteristicfunction.Therefore,theintegralequationsbecomenonlinearalgebraicequations.Newton'siterativemethodwasutilizedtosolvethenonlinearalgebraicequations.Toguaranteetheconvergenceoftheiterativemethod,deflectionatcenterwastakenascontrolparameter.Correspondingloadswereobtainedbyincreasingdeflectiononebyone.Asanumericalexample,elasticcharacteristicofshallowcorrugatedshellswithsphericaltaperwasstudied.Calculationresultsshowthatcharacteristicofcorrugatedshellschangesremarkably.Thesnappinginstabilitywhichisanalogoustoshallowsphericalshellsoccurswithincreasingloadifthetaperisrelativelylarge.Thesolutionisclosetotheexperimentalresults.

简介：RandomfatigueofweldedK-typetubularjointssubjectedtoaxialorout-of-planebendingloadisanalyzed.Byconsideringthesizesofinitialsurfacecracksandmaterialconstantsasrandomvariableswithsomeprobabilisticdistributions,incorporatingtheeffectoftheweld,fivehundredrandomsamplesaregenerated.Statisticalcomputationalresultsoflifeofcrackpropagationandeffectofchangeofcrackshapearefinallyobtainedandcomparedwithexperimentaldataavailablebasedonaregressionanalysis.Meanwhile,crackpropagationbehaviorsarealsoinvestigated.

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简介：Liquid-solid(L-S)masstransfercoefficients(Ks)werecharacterizedinagas-liquid-solid(G-L-S)three-phasecountercurrentmagneticallystabilizedbed(MSB)usingamorphousalloySRNA-4asthesolidphase.Effectsofsuperficialliquidvelocity,superficialgasvelocity,magneticfieldstrength,liquidviscosityandsurfacetensionwereinvestigated.ExperimentalresultsindicatedthattheexternalmagneticfieldincreasedKsinthree-phaseMSB,ascomparedtothoseinconventionalG-L-Sfluidizedbeds;thatKsincreasedwithmagneticfieldstrength,superficialgasandliquidvelocitiesanddecreasedwithliquidviscosityandsurfacetension;andthatKsshoweduniformaxialandradialdistributionsexceptforsmallincreasesclosetothewall.DimensionlesscorrelationswereestablishedtoestimateKsoftheG-L-ScountercurrentMSBusingSRNA-4catalyst,withanaverageerrorof3.6%.

简介：K-phillipsite用一个热水的方法被准备。可溶的玻璃和钠铝酸盐当一个器官的模板不在时被用作原料。关于K+离子的调查在房间温度被进行在海水样品和混合K+Na+答案的选择系数决定离子交换能力。样品被X光检查衍射(XRD)描绘，扫描电子显微镜学(SEM)，和精力分散光谱学(版本)。K+离子交换能力是在海水的51mg/g，选择系数在混合K+Na+答案是75.1。样品为K+有选择偏爱，并且能因此被用来有选择地从海水提取钾。由Si，艾尔，K，Na，和O组成的样品展出跨like形状并且是典型K-phillipsite结构。

简介：BycombiningChapman-EnskogexpansionwiththeBGKapproximationtoBaltzmannequationandNavier-Stokesequationwasobtained.AndanexpressionofDarcy'slawwasobtainedthroughtakingvariableaverageoverNavier-Stokesequationonsomerepresentativespaceinporousmedia,andfinallyanexamplewastakentoproveitsreliability.

简介：无刷直流电动机作为控制力矩陀螺驱动电机,要求具有10倍的最大功率倍数,这给电机的设计带来很大难度.该文提出的绕组换接运行,在满足控制力矩陀螺驱动要求的前提下,不但可以使电机最大功率倍数、从而使系统逆变器容量降低,同时可以大大降低系统的损耗、提高系统的运行效率.通过理论分析和样机试验证明了绕组换接的有效性.

简介：Thispaperaimstoinvestigatethehydrodynamicbehaviorofatensionlegplatform(TLP)whenthetendonconnectionanglesarevariedat90°,70°,50°,and30°.ThreedifferenttypesofloadingconditionsareappliedtotheTLP.Conditionsinclude100-yearhurricanestormperiod,regularwavesandnoloading.TheTLPdisplayedmajorresponseinthepitchdegreeoffreedom.Amaximumreductionof14%inpitchrotationisachievedwhen100-yearhurricanestormconditionsareappliedtotheTLP.Thisoccurredin0°loadingsat30°tendonconnectionangleascomparedto90°tendonconnectionangle.Reductioninpitchrotationisalsoachievedintheregularwaveloadings.Amaximumof9%inpitchrotationisachievedduring0°waveloadingat30°tendonconnectionangleascomparedto90°.Whenthetendonconnectionangleisreducedfrom90°to30°,thenaturalfrequencyoftheTLPincreasedbothinpitchandyawdegreesoffreedomby2.55%and2.40%,respectively.

简介：Astandardconservationformisderivedinthispaper.ThehyperbolicityofHelbing’sfluiddynamictrafficflowmodelisproved,whichisessentialtothegeneralanalyticalandnumericalstudyofthismodel.Onthebasisofthisconservationform,alocaldiscontinuousGalerkinschemeisdesignedtosolvetheresultingsystemefficiently.Theevolutionofanunstableequilibriumtrafficstateleadingtoastablestop-and-gotravelingwaveissimulated.Thissimulationalsoverifiesthatthemodelistrulyimprovedbytheintroductionofthemodifieddiffusioncoefficients,andthushelpstoprotectvehiclesfromcollisionsandavoidetheappearanceoftheextremelylargedensity.

简介：Weprovideanalyticalsolutionstotheproblemsofacircularbendingofabeaminplanestrainandthetorsionofanon-circularcross-sectionbeam,thebeamsobeyingasecond-gradientelasticitylawproposedbytheauthor,followingaprevioussuggestionofdell'Isolaetal.(2009).Themotivationwastofindbenchmarkanalyticalsolutionsthatcanservetograspthephysicalfoundationsofsecondgradientelasticitylawsforheterogeneousmaterials.TheanalyticalsolutionofthecircularbeamproblempresentstheadditionaladvantagetoestablishsomenicepropertiesontheunknownsecondgradientelasticmoduliintroducedbyEnakoutsa(2014)modelandtheclassicalelasticityconstantsforbothincompressibleandcompressibleheterogeneouselasticmaterials.Aframeworktofindtheelasticmoduliofthenewmodelisalsoproposed.

简介：ThispaperisconcernedwiththediffusiveNicholson’sblowfliesequationwithnonlocaldelayincorporatedasanintegralconvolutionovertheentirepasttimeuptonowandthewholeone-dimensionalspatialdomainR.Assumethatthedelaykernelisastronggenerickernel.Bythelinearchaintechniquesandthegeometricsingularperturbationtheory,theexistenceoftravellingfrontsolutionsisshownforsmalldelay.

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简介：ThispaperusesPoincaréformalismtoextendtheLevi-Civitatheoremtocopewithnonholonomicsys-temsadmittingcertaininvariantrelationswhoseequationsofmotioninvolveconstraintmultipliers.Sufficientcondi-tionsallowingsuchextensionareobtainedand,asanapplicationofthetheoryageneralizationofRouth’smotionispresented.

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简介：The1/3subharmonicsolutionfortheDuffing'sequationisinvestigatedbyusingthemethodsofharmonicbalanceandnumericalintegration.Thesensitivityofparametervariationforthetransientprocessandthetransientprocessfortheperturbanceinitialconditionsarestudied.Overandabove,theprecisionofnumericalintegrationmethodisdiscussedandthenumericalintegrationmethodiscomparedwiththeharmonicbalancemethod.Finally,asymptoticalstabilityofthepuresubharmonicoscillationselementisinspected.