简介：Thispaperpresentsananalyticalstudyontheinfluenceofedgerestrainingstiffnessonthetransversevibrationsofrectangularplatestructure.AnimprovedFourierseriesmethodwasemployedtoanalyzethetransversevibrationofplatestructurewithgeneralelasticallyrestrainedboundaryconditions.AlinearcombinationofadoubleFourierseriesandeightauxiliarytermswassoughtastheadmissiblefunctionoftheflexuraldisplacementoftheplate,eachtermbeingacombinationofapolynomialfunctionandasinglecosineseriesexpansion.Theauxiliarytermswereintroducedtoensureandimprovethesmoothnessoftheoriginaldisplacementfunctionanditsderivativesattheboundaries.Severalnumericalexamplesweregiventodemonstratethevalidityandaccuracyofthecurrentsolution.Theinfluencesoftranslationalandrotationalstiffnessonthenaturalfrequenciesandmodeshapesofplatewereanalyzedbynumericalresults.Theresultsshowthatthetranslationalstiffnesshasbiggerinfluenceonthenaturalfrequenciesthantherotationalstiffness.Itisgenerallywellknownthatlittlechangeoftherotationalstiffnesshaslittleinfluenceonthemodeshapesofplate.However,thecurrentworkshowsthataverylittlechangeofrotationalstiffnessvaluemayleadtoalargechangeofthemodeshapesofasquareplatestructure.

简介：本文研究一类正则Sturm-Liouville（S-L）问题，其中具有转换条件，并且在边界条件中带两个谱参数.将S-L问题的特征值和特征函数的研究，转换为适当Hilbert空间H中线性算子A的特征问题.同时，探究上述问题新算子A特征函数系的完备性.

简介：OnMarch26,2010anunderwaterexplosion(UWE)ledtothesinkingoftheROKSCheonan.TheofficialMultinationalCivilian-MilitaryJointInvestigationGroup(MCMJIG)reportconcludedthatthecauseoftheunderwaterexplosionwasa250kgnetexplosiveweight(NEW)detonationatadepthof69mfromaDPRK'CHT-02D'torpedo.KimandGitterman(2012a)determinedtheNEWandseismicmagnitudeas136kgatadepthofapproximately8mand2.04,respectivelyusingbasichydrodynamicsbasedontheoreticalandexperimentalmethodsaswellasspectralanalysisandseismicmethods.ThepurposeofthisstudywastoclarifythecauseoftheUWEviamoredetailedmethodsusingbubbledynamicsandsimulationofpropellersaswellasforensicseismology.Regardingtheobservedbubblepulseperiodof0.990s,0.976sand1.030swerefoundincaseofa136NEWatadetonationdepthof8musingtheboundaryelementmethod(BEM)and3Dbubbleshapesimulationsderivedfora136kgNEWdetonationatadepthof8mapproximately5mportsidefromthehullcenterline.Hereweshowthroughanalyticalequations,modelsand3Dbubbleshapesimulationsthatthemostprobablecauseofthisunderwaterexplosionwasa136kgNEWdetonationatadepthof8mattributabletoaROKlittoral'landcontrol'mine(LCM).

简介：Thispaperpresentsanimprovedunstructuredgridimmersedboundarymethod.Theadvantagesofbothimmersedboundarymethodandbodyfittedgridswhicharegeneratedbyunstructuredgridtechnologyareusedtoenhancethecomputationefficiencyoffluidstructureinteractionincomplexdomain.TheNavier-StokesequationwasdiscretizedspaciallywithcollocatedfinitevolumemethodandEulerimplicitmethodintimedomain.TherigidbodymotionwassimulatedbyimmersedboundarymethodinwhichthefluidandrigidbodyinterfaceinteractionwasdealtwithVOS(volumeofsolid)method.AnewVOScalculationmethodbasedongraphwaspresentedinwhichbothimmersedboundarypointsandcrosspointswerecollectedinarbitraryordertoformagraph.Themethodisverifiedwithflowpastoscillatingcylinder.

简介：研究了一类具有转换条件且在两个边界条件中带谱参数的Sturm-Liouville算子特征的渐近式.将对上述问题特征值与特征函数的研究,转化为考虑定义在Hilbert空间H中一个算子A的特征值与特征函数问题,并通过对基本解的渐近分析求出特征值与相应特征函数的渐近式.