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1.
IntroductionNeedingonlynodeinformation ,withouttheconnectivityelement,themeshlessmethodsaredevelopingrapidly ,andhavemanykindsofmeshlessmethods,suchasEFEM[1],SPH[2 ],RKPM[3],PU[4 ].Weightfunctionanditsparametersplayanimportantroleinsimulatingdisplacementfiledinmeshlessmethod[1].Togivethereasonableinfluenceradiusofweightfunctionisverydifficult.Theinfluenceradiusofweightfunctionisgivenbythesectioncontinualfunction ,andtheuseofinfluenceradiusortheuseofweightfunctionemphasisonthesimulationde…  相似文献   

2.
IntroductionForthestudyofwellposednessontheinitialorboundaryproblemsabouttheEulerequations,therearemanyimportantresultsgivenbydifferentmethodsindifferentfunctionclasses[1]- [4 ].Thepaper (Ⅰ )oftheauthordiscussedtheill_posednessoftheCauchyproblemswhichsatisfythesameconditionsoftheinitialvalueproblematthehypersurfacet=t( 0 ) +g(x) ,g(x) ≠constant,g(0 ) =0 R4,andgavetwodifferentformalsolutions[5 ].Italsogavetheformulasforcomputation .Inthepresentpaper,twokindsofillposednessoftheEulerequation…  相似文献   

3.
IntroductionAsanimportantnumericalmethod ,BoundaryElementMethod (BEM)hasbeenappliedinmanyareas[1].However,theBEMhasthedifficultiesofcalculatingsingularintegralsatnodesonboundaryoratinteriorpointsveryclosetotheboundary .TheaccuracyoftheBEMdependsontheprecisionofthecalculatedvaluesofthesingularintegrals,toagreatdegree.Manyresearchersdevotethemselvestothetreatmentofthesingularintegrals[2~3],whicharereviewedindetailbyRef.[4] .Ageneralregularizationalgorithmofevaluatingthephysicalquantitiesa…  相似文献   

4.
IntroductionCompressivepropertiesofcompositelaminatesafterlowvelocityimpactareoneofthemostseriouscircumstanceswhichmustbetakenintoaccountindamagetolerancedesignofcompositestructures[1].Impactdamagegenerallymanifestsintheformsofdelaminations,matrixcracksandfibrefracture[2 ,3].Sofaralotofresearcheshavebeentakeninlowvelocityimpactbehaviorofcompositelaminatesandtheirpost_impactcompressiveproperties.Compressivefailuremechanismsofcompositelaminatesafterlowvelocityimpacthavenotbeenknownclearly .Ther…  相似文献   

5.
IntroductionThispaperisadirectcontinuationofthepreviouspapers [1 ,2 ] .ThefieldequationsoflinearcouplestresselasticityweredevelopedbyMindlinandTiersten[3].AgeneralcouplestresstheorywaspresentedbyToupin[4 ].Eringen[5 ,6 ]haspointedoutthatthecouplestresstheoriesofelasticmediafluidsmaybededucedfromthemicropolarelasticityandfluidmechanicswhenthemicrorotationsiandψiareconstrainedbytherotationvectorωiofclassicalelasticityandvorticityvectorrioffluidmechanics,respectively .AnexpressionoftheJ_int…  相似文献   

6.
IntroductionThediscoveryofthefirstcarbonnanotubes[1]hasattractedwideattentionandstimulatedextensivestudies[2 - 5 ].Thestudiesshowedthatthecarbonnanotubesexhibitsuperiormechanical,electronicandchemicalproperties.Onthemechanicalbehavior,thecarbonnanotubespossessexceptionallyhighstrength ,stiffnessandelasticmodulus.Theestimatemodulusofthecarbonnanotubemayreachashighas 1TPa.Itisthelargestofallknownmaterials.Thestrengthorstiffnessishigherthananyknownfiber[3].Thecarbonnanotubeareusedascompositemat…  相似文献   

7.
IntroductionThedynamicandcontrolofcoupledrigid_flexiblesystemisaleading_edgeresearchsubjectthathasdrawnextensiveattentionfromtheacademiccommunityintheworld[1].TheresearchconductedbyKaneetal.in 1 987[2 ]suggestedthat,thetraditionalmodelapplyingstructuraldynamicsassumptionaboutelasticdeformationindiscriminately[3,4 ],ineffect,hasneglectedtheso_called“dynamicstiffening”effectresultedfromcoupledrigid_flexiblesystem .Therefore ,itisofparticularimportancetoresearchtheactionofcoupledrigid_flexibles…  相似文献   

8.
I. INTRODUCTION Sisal ?bre is a promising natural ?bre, which has a potential application as reinforcement in compositematerials[1 , 2]. It has relatively high strength, high modulus, low density, particularly low price andabundant availability[3??5]. Compared to glass ?bre, sisal ?bre has several advantages. It is environment-friendly, recyclable, and the price is almost one-ninth that of glass ?bre and one-?ve hundredth of carbon?bre[6]. Fundamental considerations of design and ap…  相似文献   

9.
This paper obtains some fixed point theorems of semidifferentiable semmicompacl l-set-contraction maps, which extend some known results in [1, 2, 4, 5, 7].  相似文献   

10.
This paper discusses the following non-linear systems of second order coefficients:This paper is the generalization of works[1]and[2].  相似文献   

11.
Introduction Theuseofeddycurrenthasbeenwellrecognizedasamethodforthenondestructive testing(NDT)ofconductingmaterials[1].Eddy currentswithlow frequencyareinducedin thematerialundertestbymeansofthesurfacescanninginterrogatingcoildrivenbyatime varyingcurrent…  相似文献   

12.
In this paper, using the PLK method and reductive perturbation method,we obtainedthe second approximation to cnoidal waves at the free surface and ihterface for the two-fluid system considered in[1].The corresponding results in[3]and[4]may be obtained asspecial cases in this paper.  相似文献   

13.
IntroductionFlowoffibresuspensionshasbeenveryfamiliarinmanyindustrialfields.Fibreadditivesplayanimportantroleindragreductioninmanytypesofflow[1- 3].Inthesuspensions,somebehavioroftheflowmaybealteredbythefibres.Oneoftheimportantexamplesisthehydrodynamicsta…  相似文献   

14.
IntroductionThecorrespondencebetweenH∞ decentralizedcontrolandmodalsynthesistheoryispresentedinpart (I)ofthepaper[1].WheretheorthogonalityandtheexpansiontheoremofeigenfunctionsofsubsystemsH∞ controlareintroduced .Basedontheseresults,thefollowingsectionspresentthemodalsynthesismethodforthecomputationoftheoptimalH∞ normofthedecentralizedcontrolsystemsandnumericalexamples.Notethatthroughoutthepaperequation(I_n)denotesequation (n)inpart (I)ofthepaper[1].1 OptimalParameterComputationforGlob…  相似文献   

15.
IntroductionChaoticistheinherentrandomnessinthedefinitesystem .Thedefinitenessiscausedbythesysteminternalsbutnotbytheexternaldisturbance[1- 4],whiletheinherentrandomnessistheirregularanddifficult_to_be_predictedbehaviorofthesystem[5 ,6 ].Whatismostattractive…  相似文献   

16.
The sludy of bending of cracked circular cylinders is of more significance.The bendingof cylinders containing radical crack or cracks was discussed by refs.[1]-[4]and that ofconcentrically craked circular cylinders was studied by[5].Continuing[6]and usingcomplex variable methods in elasticity,this paper deals with the bending problems of acircular cylinder,containing an internal linear crack at any position under an acting forceperopendicular to the crack.The general forms of displacements stresses,and stress-intensity factors,expressed in terms of series,are obtained and to this bending problemswith small Ah are presented good approximate formulas for the stress-intebsity factorswhose variations with the center of the crack are analysed.Finally,the twist angle per unitlength and the center of bending for the radically cracked circular cylinder,one of whosecrack-tips is located at the origin,have been computed and the results are almost the sameas that calculated in[1].  相似文献   

17.
IntroductionSoilisthemostcommonlyusedconstructionmaterialincivilengineeringandhydraulicengineering .Thecharacteristicsofsoilhavebeeninvestigatingfornearlyonehundredyears.Butbecauseofitscomplexstructure,changeableenvironmentandbeingsensitivetotheoutsideconditions,thesoiloftenshowsvariedproperties[1,2 ].Themaindifficultytothedevelopmentofgeotechnicalmechanicsishowtosetupconstitutiveequationswhichcouldsatisfactorilyaccountforengineeringpropertiesofsoil[3].Manyconstitutivemodelshavebeenformedinth…  相似文献   

18.
IntroductionThesleighproblemisaclassiconeinnonholonomicdynamics.ThesolutionstotheproblemwereobtainedbyС .А .Чаплыгин( 1 898)andC .Carathodory( 1 93 3 ) [1].Thereference [2 ]presentedafewquestionablepointsinthesolutions .Anothersolutionwasofferedinthereference[3 ] .Butthe…  相似文献   

19.
20.
In this paper,the author proves by the methode of energy estimates the existence anduniqueness of global strong solutions of barotopic nondivergent model and baroclinicquasi-geostrophic quasi-nondivergent model.The two models are fundamental ones inatmospheric dynamics.The results here generalize the outcome given by the author in[3]-[5]and verify a conjecture posed by Zeng Qing-cun in[1].  相似文献   

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