简介：Aprecisetangentialcontactdampingmodelisproposed,whichincludesthelateralcontactoftheupper-lowerasperitiesandtheinteractionofadjacentasperities.Theeffectsofthenormalstaticpreload,frequency,andamplitudeoftangentialdisplacementonthetangentialcontactdampingwereanalyzedbysimulation,respectively.Furthermore,theresultsofsimulationareverifiedbyexperiment.Thetangentialcontactdampingofconsideringtheinteractionandlateralcontactofasperityisveryclosetotheexperimentalresults.

简介：Forafinitebeamwithanonzerogapdistance,anasymmetricconcentratedloadcanbeeitherinsideoroutsideofthecontactzone.Anewgoverningequationisgivenforthecaseofaconcentratedloadoutsidethecontactzone.Bynumericallysolvingtheleft-sideandright-sidecontactlengthsofthebeam,acriterionisestablishedtodeterminewhethertheconcentratedloadisinsideoroutsidethecontactzone.Amoregeneralapproachonthetensionlesscontactofabeamisthuspresented.

简介：预先滑动的政体典型地在机械系统的动态建模被忽视。然而，处于静态的磨擦引起的接触状态的变化可以减少位置的精确性和控制精确。为了调查在接触之间的关系，地位和接触在预先滑动强迫磨擦，一个光试验性的方法在这份报纸被介绍。与这个方法，在透明材料的接口的真实接触状态能被使用处理技术的一幅图象基于光的全部的思考原则观察。新奇安装，包括一双矩形的trapezoidal块，被建议解决精确地把不同正切、正常的力量用于接触接口的挑战性的问题。改进Otsus方法被用于测量。通过在polymethylmethacrylate(PMMA)上执行的试验性的研究，接触粗糙的数量被证明是影响真实接触区域的主导的因素。在在预先滑动的政体的真实接触区域和接触力量之间的关系被学习，并且在接触接口的静态的磨擦的分发是讨论的品质上。真实接触区域与增加静态的磨擦一起在膨胀的新现象被识别。上述的关系在在一个经常的正常压力下面的接触接口是近似线性的，并且磨擦应力的分发从前缘减少到后面的边。

简介：在这份报纸，到有弄弯的接触边界的有弹性的接触问题的线性有限元素近似被考虑。错误界限O(h[啜?])与为接触边界和平常的常规三角测量连续地可辨的twotimes的要求被获得，当时I.Hlavacek等。获得了错误界限O(h[啜?])与为接触边界和三角测量的额外的整齐连续地可辨的三次的要求(c.f[2])。[从作者抽象]

简介：Weconsideramathematicalmodelwhichdescribesacontactbetweenadeformablebodyandafoundation.ThecontactisbilateralandmodelledwithTresca’sfrictionlaw.Thegoalofthispaperistostudyanoptimalcontrolproblemwhichconsistsofleadingthestresstensorascloseaspossibletoagiventarget,byactingwithacontrolontheboundaryofthebody.Westateanoptimalcontrolproblemwhichadmitsatleastonesolution.Wealsointroducetheregularizedcontrolproblemforwhichwestudytheconvergencewhentheregularizationparametertendstozero.Finally,anoptimallyconditionisestablishedforthisproblem.

简介：Amechanicsmodelisdevelopedforthecontactradiusofstampswithpyramidtipsintransferprinting.Thisisimportanttotherealizationofreversiblecontrolofadhesion,whichhasmanyimportantapplications,suchasclimbingrobots,medicaltapes,andtransferprintingofelectronics.Thecontactradiusisshowntoscalelinearlywiththeworkofadhesionbetweenthestampandthecontactingsurface,andinverselywiththeplane-strainmodulusofthestamp.Italsodependsontheconeangleandtipradiu...

简介：Adiscussionaboutthebifurcationandnon-uniquenessofsolutionsintheanalysisofthermo-mechanicalcontactproblemswithinitialgapisgiven.WithoutJossofgenerality,amechanicalcontactprob-lemcoupledwithsteadyheattransferisstudiedandanexampleofnon-uniquenessofsolutionscausedbythethermo-mechanicalmechanismispresented.Theimportantworkisthatthenon-uniquenessofsolutions,whichisdifferentfromthatfoundintheanalysisofthetraditionalfrictionalcontactproblems,isstudiedindetail.Thepossibleoscillationandnon-convergenceproblemsintheiterationprocessofthenumericalcom-putationarediscussed,andanenhancedalgorithmisputforwardtoovercomethedifficulties.

简介：Thepaperproposesaphysicalmodelforthemotionofthecontactlineandthegas-liquidinterface.Thelocalmotionofthecontactlineatthesolidwallisassumedandtheinterfacebetweengasandliquidistracedbyalevelfunction.Thefinitevolumemethodandstaggeredgridsareusedtosolvethegoverningequationnumerically.Themotionofthewatercolumninaverticalpipeiscomputedandtheresultsareingoodagreementwithexperimentaldata.

简介：Thispaperisintendedtobeafirststeptowardsthecontinuousdependenceofdynamicalcontactproblemsontheinitialdataaswellastheuniquenessofasolution.Moreover,itprovidesthebasisforaproofoftheconvergenceofpopulartimeintegrationschemesastheNewmarkmethod.WestudyafrictionlessdynamicalcontactproblembetweenbothlinearlyelasticandviscoelasticbodieswhichisformulatedviatheSignorinicontactconditions.ForviscoelasticmaterialsfulfillingtheKelvin-Voigtconstitutivelaw,wefindacharacterizationoftheclassofproblemswhichsatisfyaperturbationresultinanon-trivialmixofnormsinfunctionspace.Thischaracterizationisgivenintheformofastabilityconditiononthecontactstressesatthecontactboundaries.Furthermore,wepresentperturbationresultsfortwowell-establishedapproximationsoftheclassicalSignorinicondition:TheSignoriniconditionformulatedinvelocitiesandthemodelofnormalcompliance,bothsatisfyingevenasharperversionofourstabilitycondition.

简介：Thepaperpresentstheformulationandapproximationofastaticthermoelasticityproblemthatdescribesbilateralfrictionalcontactbetweenadeformablebodyandarigidfoundation.Thefrictionisintheformofanonmonotoneandmultivaluedlaw.Thecouplingeffectoftheproblemisneglected.Therefore,thethermicpartoftheproblemisconsideredindependentlyontheelasticityproblem.Forthedisplacementvector,weformulateonesubstationaryproblemforanon-convex,locallyLipschitzcontinuousfunctionalrepresentingthetotalpotentialenergyofthebody.Allproblemsformulatedinthepaperareapproximatedwiththefiniteelementmethod.

简介：AmoregeneralmodeldescribingPCMclose-contactmeltingoutsideahotsphereisdevelopedwiththeaidofintroducingaparamterαandpresentingasupplementaryequationforthefirsttimeinthispaper.Thegoverningintegral-differentialequationsaresolvedbynumericalmethod.Themelt-filmthicknessvariationalongthesurfaceofsphereisobtainedreasonablyduetotheconsiderationoftheinterfaceshapemoreprecisely,ThecalculationresultesofPecletnumber,heattransferredandpressuredistributionarealsocomparedwiththatinliterature,Themodelpresentedinthispapercandescribethewholeclose-contactregionandthewholecontactmeltingprocess.Close-contactmeltinginsphericalorcylindricalcapsulestowhichthemodelcanbeextendedisalsodiscussedbriefly.

简介：1.TheproblemTheterm'concussion'referstoacommonformoftraumaticbraininjury,whichtypicallyoccursafterabloworinjurytothehead.Ithasbeendescribedasa'complexpathophysiologicalprocessaffectingthebrain,inducedbybiomechanicalfactors',andshearforcesinducedbyrotationalaccelerationarebelievedtobetheprimarymechanismofinjuryinconcussion.~1TheincidenceofconcussionintheUKhasbeenshowntobeup

简介：Itiswellknownthatsurfaceroughnesshasaveryimportanteffectonsuperhydrophobicity.TheWenzelandCassie-Baxtermodels,whichcorrespondtothehomogeneousandheterogeneouswettingrespectively,arecurrentlyprimaryinstructionsfordesigningsuperhydrophobicsurfaces.However,theparticulardropshapethatadropexhibitsmightdependonhowitisformed.Awaterdropcanoccupymultipleequilibriumstates,whichrelatetodifferentlocalminimalenergy.Insomecases,bothequilibriumstatescanevenco-existonasamesubstrate.Thustheapparentcontactanglesmayvaryandhavedifferentvalues.WediscusshowtheWenzelandCassie-Baxterequationsdeterminethehomogeneousandheterogeneouswettingtheoretically.Contactangleanalysisonhierarchicalsurfacestructureandcontactanglehysteresishasbeenputspecificattention.Inparticular,westudytheenergybarrieroftransitionfromCassie-BaxterstatetoWenzelstate,basedonexistingachievementbypreviousresearchers,todeterminethepossibilityofthetransitionandhowitcanbeinterpreted.Ithasbeendemonstratedthatsurfaceroughnessandgeometrywillinfluencetheenergyrequiredforadroptogetintoequilibrium,nomatteritishomogeneousorheterogeneouswetting.

简介：Basedonelementarygrouptheory,theblockpivotmethodsforsolv-ingtwo-dimensionalelasticfrictionalcontactproblemsarepresentedinthispaper.Itisprovedthatthealgorithmsconvergewithinafinitenumberofstepswhenthefrictioncoefficientis'relativesmall'.Unlikemostmathematicalprogrammingmeth-odsforcontactproblems,theblockpivotmethodspermitmultipleexchangesofbasicandnonbasicvariables.

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简介：在西北的伊朗的Soursat变形建筑群(SMC)是SanandajSirjan变形的带的部分。建筑群由不同变形、Pluto的岩石组成，但是被由石榴石，十字石，kyanite，fibrolite，堇青石，和andalusite组成的metapelites统治。在片岩的Porphyroblastsschistosity的一样的织物，和三个阶段是在场的。内部schistosity(Sn)包括小道也是偏移量由结合extensionalschistosity(Sn+1)和一秒(Sn+2)的集合那crenulates(Sn+1)。多相的变态在建筑群是在场的。石榴石，十字石，kyanite，和fibrolite集合在M1变形事件期间保存条件。这个集合产出645瑩挠湡戠?敳癲摥愠?的磅估计?敮?敧灯票楳慣?敭桴摯椠?桴?硥汰牯瑡潩?景挠浯汰硥琠牥慲湩瀠票楳杯潮祭愠敲??档愠?潭湵慴湩?番杮敬?敤敳瑲?慭獲?漠獮潨敲漭晦桳牯?牴湡楳楴湯污愠敲?湡?潳漠?愠摮栠獡愠?硥整獮癩?灡汰捩瑡潩?牰獯数瑣椠?桃湩?湩琠敨映瑵牵吗？

简介：ThetransientresponsetolongitudinalimpactofflexiblerodswithHertzcontactiscloselyrelatedtotheextentofdeformationswithdifferentimpactparameters.BymeansofLS-DYNA,fordifferentradiusanddifferentspeeds,thelongitudinalimpactofahammerwitharoundedendonadrillrodisnumericallysimulatedinthisarticle.Simulationsdemonstratethatthereisanobviousdif-ferencebetweenanalyticalsolutionandnumericalsolutiononconditionofshortcurvatureradius.Inthecircumstancecontactpressureincreases,theboundaryoftheyieldzoneexceedsthatofthecontactzone,andthesignificantplasticdeformationreducestheintensityofcontactpressurepulse.Contactforce-timecurvesinloadingandunloadingphasesshiftdown.Thenumericalsolutionisingoodagree-mentwithanalyticalsolutiononconditionoflargecurvatureradiusandimpactspeeds.Thedeforma-tionofyieldregionisconstrainedbythesurroundingelasticregionandnosignificantplasticdeforma-tionappears.

简介：尽管全面结构或结构的成员没完全被破坏，因为高速度水泥碎片，源于接触爆炸的具体平板或墙的分裂在结构内组成风险到人员和设备。正确地预言任何潜力引起的损坏联系爆炸能导致更好的筑堡设计承受强风装载。学习涉及具体平板和墙的分裂的机制因此意义大。这个话题上的存在研究经常采用简化材料模型和1D波浪分析，它不能在分裂过程复制现实主义的反应。数字模拟因此用LS-DYNA在免费的空中在不同接触强风装载下面被执行。复杂具体、增强的酒吧材料模特儿被收养，考虑紧张和压缩上的紧张率效果。侵蚀技术被用来在张力的应力下面为材料的破裂和失败建模。变丑的完整的过程和平板和平凡具体平板这样是的增强的水泥(RC)的动态损坏写实地观察了。随炸药的数量的增加，损坏坑增加和平板的尺寸经历四个不同损坏模式，这被注意，也就是爆炸的坑，spalling，穿孔，并且打。在增强锁的RC平板表演的平凡具体平板和那些的模拟结果之间的比较能提高正直和平板的砍的抵抗到某个程度，并且同时稀释喷射速度和减少水泥的尺寸碎裂。因此，优化加强安排能改进平板和墙的反分裂能力到某个程度。

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简介：Themainobjectiveofthisresearchistoevaluatethewettabilityoftheprocessedbamboosurfaces.Theimportantsurfaceenergyandacid-basepropertiesforprocessedbamboohavebeenestimatedbyusingcontactangletechniques.Accordingtotheresults,thechangeofageshasapositiverelationwiththecontactanglesofwateronprocessedbamboo.Thecontactangleswereincreasedafterthebamboosurfacetreatedinhightemperatureconditionandpreservation.Thedifferenttreatmethodshaveastro...