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简介：Thispaperaddressesanonlinearfeedbackcontrolproblemforthechaoticarchmicro-electro-mechanicalsystemwithunknownparameters,immeasurablestatesandpartialstate-constraintsubjectedtothedistributedelectrostaticactuation.Toreflectinherentpropertiesanddesigncontroller,thephasediagrams,bifurcationdiagramandPoincaresectionarepresentedtoinvestigatethenonlineardynamics.TheauthorsemployasymmetricbarrierLyapunovfunctiontopreventviolationofconstraintwhenthearchmicro-electro-mechanicalsystemfacessomelimits.AnRBFneuralnetworksystemintegratingwithanupdatelawisadoptedtoestimateunknownfunctionwitharbitrarilysmallerror.Toeliminatechaoticoscillation,aneuro-adaptivebacksteppingcontrolschemefusedwithanextendedstatetrackingdifferentiatorandanobserverisconstructedtolowerrequirementsonmeasuredstatesandprecisesystemmodel.Besides,introducinganextendedstatetrackingdifferentiatoravoidsrepeatedderivativeforthevirtualcontrolsignalassociatedwithconventionalbackstepping.Finally,simulationresultsarepresentedtoillustratefeasibilityoftheproposedscheme.

简介：Manymoderncontrolapplicationsareinterdisciplinaryinnature.Varietyofdisciplinesareorientedonapplicationofcontroltheoryandmodelingofmechanical/biomechanicalsystemstosolvepracticalproblemsintheirspecificfields.Bearingthisinmind,thereareincludedinthisspecialsubjectsomeinterestingcontributionscoveringdifferentareassuchasbifurcationsandchaosindynamicalsystems,stabilityofdynamicalsystems,originalnumericalmethodsofvibrationanalysis,non-smoothsystems,engineeringsystemsanddifferentialequations,controlindynamicalsystems,asymptoticmethodsinnonlineardynamics,vibrationsoflumpedandcontinuoussystems,dynamicsinlifesciencesandbioengineering.

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简介：Morerecently,avariationalapproachhasbeenproposedbyLinandWangfordampingmotionwithaLagrangianholdingtheenergytermdissipatedbyafrictionforce.However,themodifiedEuler-LagrangeequationobtainedwithintheirformalismleadstoanincorrectNewtonianequationofmotionduetothenonlocalityoftheLagrangian.Inthiscommunication,wegeneralizethisapproachbasedonthefractionalactionlikevariationalapproachandweshowthatundersomesimplerestrictionsconnectedtothefractionalparametersintroducedinthefractionalformalism,thisproblemmaybesolved.

简介：很多读者听说过飞机的“灵巧蒙皮”这个概念，知道那是未来高性能飞机不可缺少的先进技术，而支持“灵巧蒙皮”得以实现的基础．就是微机电系统。苑伟政教授深入浅出的讲解让我们了解了微机电系统在军事领域中的强大作用。

简介：Byusingthewell-developedintegraltransformmethodology,thedynamicresponseofstressandelectricdisplacementaroundafinitecrackinaninfinitepiezoelectricstripareinvestigatedunderarbitrarydynamicanti-planeloads.Thedynamicstressintensityfactorsandelectricdisplacementareobtainedanalytically.Itisshownthatthedynamiccrack-tipstressandelectricfieldstillhaveasquare-rootsingularity.Numericalcomputationsforthedynamicstressintensityfactorshowthattheelectricloadhasasignificantinfluenceonthedynamicresponseofstressfield.Thehighertheratioofthecracklengthtothewidthofthestrip,thehigherthepeakvalueofthedynamicstressintensityfactoris.Ontheotherhand,thedynamicresponseoftheelectricfieldisdeterminedsolelybytheappliedelectricload.Theelectricfieldwillpromoteorretardthepropagationofthecrackdependingonthetimeelapsesincetheapplicationoftheexternalelectro-mechanicalloads.

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简介：Ｎｏｅｔｈｅｒ’ｓｔｈｅｏｒｅｍｒｅｖｅａｌｓｔｈｅｉｎｎｅｒｃｏｎｎｅｃｔｉｏｎｂｅｔｗｅｅｎｔｈｅｃｏｎｓｅｒｖａｔｉｏｎｌａｗｓａｎｄｔｈｅｄｙｎａｍｉｃａｌｓｙｍｍｅｔｒｙｏｆｄｙｎａｍｉｃａｌｓｙｓｔｅｍｓ．Ｉｎｔｈｅｒｅｃｅｎｔｔｗｅｎｔ...

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简介：Themolluskshellmobilizescalciumfromenvironmentforskeletalmineralization.Thisoccursthroughsynthesizingsolidsinsolutioninthepresenceoforganicmoleculesofspecificinteriorregionsoftheconchshell.TheultrastructureandmicrohardnessoftheHemifusustubaconchshelllivingintheHuang/Boseaareaareinvestigatedinthepaper.Itisshownthatthecompositionandmicrostructureofthemolluskshellvaryindifferentpositions.Theprodissoconchshellconsistsonlyofaragonitewiththecrossed-lamellarmicrostructure.WhilethespiralshellandthebodyshelloftheHemifusustubaconchshellarecomposedofonecalcitelayerandseveralaragonitelayers.Thecalcitelayerconsistsofcylindricalgrains,butthearagonitelayersarecrossed-lamellarultrastructureatthreesizescales.Theminimumstructuresize(thethird-orderlamella)isatabout20nm-80nm.Themarginofshellapertureisonlycomposedofcalcitewithcylindricalgrains.ThisnaturaloptimizationoftheshellmicrostructureisintimatelyduetothegrowthoftheOrganicmatrix.Atdifferentpositionsthemicrohardnessofmolluscshellisdifferentduetodifferentcrystalstructuresandcrystalarrangements.Thegrowthprocessofshellsallowsaconstantrenewalofthematerial,thusenablingtheirfunctionaladaptationtoexternalenvironments.

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简介：Indentationisasimpleandnondestructivemethodtomeasurethemechanicalpropertiesofsoftmaterials,suchashydrogels,elastomersandsofttissues.Inthiswork,wehavedevelopedamicro-indentationsystemwithhigh-precisiontomeasurethemechanicalpropertiesofsoftmaterials,wheretheshearmodulusandPoisson’sratioofthematerialscanbeobtainedbyanalyzingtheload–relaxationcurve.Wehavevalidatedtheaccuracyandstabilityofthesystembycomparingthemeasuredmechanicalpropertiesofapolyethyleneglycolsamplewiththatobtainedfromacommercialinstrument.Themechanicalpropertiesofanothertypicalpolydimethylsiloxanesamplesubmergedinheptanearemeasuredbyusingconicalandsphericalindenters,respectively.ThemeasuredvaluesofshearmodulusandPoisson’sratioarewithinareasonablerange.

简介：在这篇论文，Noether谎言对称和概括古典机械系统的保存数量被学习。定义和为在组的一般无穷小的转变下面的系统的Noether谎言对称的标准被给。Noether保存了数量，Hojman保存了从Noether谎言对称推出的数量被获得。一个例子被给说明结果的申请。

简介：Backlash-likehysteresisisoneofthenonsmoothandmulti-valuednonlinearitiesusuallyexistinginmechanicalsystems.Thetraditionalidentificationmethodisquitedifficulttobeusedtomodelthesystemsinvolvedwithsuchcomplexnonlinearities.Inthispaper,anonsmoothrecursiveidentificationalgorithmforthesystemswithbacklash-likehysteresisisproposed.Inthismethod,theconceptofClarkesubgradientisintroducedtoapproximatethegradientsatnonsmoothpointsandtheso-calledbundlemethodisusedtoobtaintheoptimizationsearchdirectioninnonsmoothcases.Then,arecursivealgorithmbasedontheideaofbundlemethodisdevelopedforparameterestimation.Afterthat,theconvergenceanalysisofthealgorithmisinvestigated.Finally,simulationresultstovalidatetheproposedmethodonasimulatedmechanicaltransmissionsystemarepresented.

简介：为灵活multibody系统的模拟的一个重要问题是自由的灵活身体度的减小。根据安全问题被担心，自由的灵活的度的减小介绍的错误的知识有用、很重要。

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简介：Thinfilm/substratematerialsystemshavebeenwidelyusedinvariousindustriessuchasaerospace,automotive,marineandelectronics.Oneexampleisthermalbarriercoatings(TBCs):TBCsareextensivelyappliedtometalliccomponentsongasturbineenginesinordertoprotectthemfromhighandprolongedheatloads,andtheyplayanessentialroleintheaircraftindustry.Anotherexampleislaminatedpolymermatrixcomposites(PMCs),reinforcedwithfiberssuchascarbon,glassoraramid:Thesematerialshavebeenextensivelyemployedinavarietyofapplicationsduetotheirsuperiorpropertiesandtheimprovingeaseandcost-effectivenessoffabricatingthem.Theevaluationofmechanicalpropertiesforthinfilm/substratematerialsystemsisimperativeformoreefficientuseofthesematerialsystemsandfurtherimprovements.

简介：基于这个概念断热不变，不安和为nonholonomic的Mei对称的断热的invariants机械系统被学习。为没有不安的系统的Mei对称的准确invariants被给。到Meisymmetry的不安被讨论，为使不安的系统的Mei对称的断热的invariants被获得。

简介：Inthispaper,thehybridelectricvehiclebrakingprocessisresearched,byusingvariablesconsistsofHEVspeed,motorspeed,andstateofchargeestablished,functionsofmechanicalbrakingforce,regenerativebrakingforceandefficiencyofenergyrecoveryareconstructed,andthecontrolgoalistomaximizationtheenergyrecoveryefficiency.Underthefeedbackcontrolstrategy,withtheconstrainconditionofbrakingstrengthandbrakingstability,combiningexperimentsinADVISOR,indifferentexperimentsofdifferentworkingconditions,wecanseethatinUDDSCycle,theregenerativebrakingefficiencyisthebest.What’smore,comparedwithstrategiesinADVISOR,strategyproposedinthispaperisobviouslybetter.