简介:LetR0,nbetherealCliffordalgebrageneratedbye1,e2,···,ensatisfyingeiej+ejei=-2δij,i,j=1,2,···,n.e0istheunitelement.Letbeanopenset.AfunctionfiscalledleftgeneralizedanalyticiniffsatisfiestheequationLf=0,(0.1)whereL=q0e0θx0+q1e1θx1+···+qnenθxn,qi>0,i=0,1,···,n.Inthisarticle,wefirstgivethekernelfunctionforthegeneralizedanalyticfunction.Further,theHilbertboundaryvalueproblemforgeneralizedanalyticfunctionsinRn+1+willbeinvestigated.
简介:在这份报纸,有变化时间的内部液体的一个灵活海洋的起床人的颤动减小被使用边界控制方法和Lyapunovs直接方法学习。完成更精确、实际的起床人动态行为,有变化时间的内部液体的海洋的起床人的模型被一个分布式的参数系统(DPS)与部分微分方程(PDE)和包含空间和时间的函数的平常的微分方程(颂诗)建模。如果变化时间的内部液体被考虑,起床人的动态回答是完全不同的。边界控制基于PDE建模的原来的无限的维数和Lyapunovs直接方法在起床人的最高的边界被设计减少起床人颤动。一致固定和靠近环的稳定性基于建议边界控制被证明。模拟结果验证建议边界控制的有效性。
简介:在易碎的材料的动态裂缝繁殖的预言仍然是许多设计的域里的一个重要问题。重新协调的技术基于放大边界,有限元素方法(SBFEM)被扩大在易碎的材料预言动态裂缝繁殖。结构第一被划分成很多superelements,仅仅的边界是有线元素的discretized的需要。在SBFEM明确的表达,僵硬和超级元素的罐头的集体矩阵与标准有限元素无缝地被联合,因此,通用性的优点和FEM的灵活性很好被维持。结构的短暂反应能用一个标准时间集成计划在时间领域直接被计算。当时,动态压力紧张因素(DSIF)能由于SBFEM的半分析的性质在裂缝繁殖期间是解决的经分解。为裂缝尖端的仅仅好网孔discretization超级元素被需要为压力紧张因素(SIF)的决心保证要求的精确性。根据预言的裂缝尖端位置,有最小的网孔变化的一个简单重新协调的算法被建议模仿动态裂缝繁殖。数字例子显示建议方法能有效地被用来包括一个中央裂缝在一个有限大小的矩形的盘子中处理动态裂缝繁殖。比较与在文学可得到的结果被做,它显示出在对方之间的好同意。
简介:Theroleplayedbythediffractionfieldontheproblemofseismicsiteeffectsisstudied.ForthatpurposewesolveandanalyzesimplescatteringproblemsunderPandSVin-planewaveassumptions,usingtwowellknowndirectboundary-element-basednumericalmethods.Afterestablishingthedifferencebetweenscatteredanddiffractedmotions,andintroducingtheconceptofartificiousandphysicallybasedincomingfields,weobtaintheamplitudeoftheFourierspectraforthediffractedpartoftheresponse:thisisachievedafterestablishingtheconnectionbetweenthespatialdistributionofthetransferfunctionoverthestudiedsimpletopographiesandthediffractedfield.Fromthenumericalsimulationsitisobservedthatthisdiffractedpartoftheresponseisresponsiblefortheamplificationofthesurfacegroundmotionsduetothegeometriceffect.Furthermore,itisalsofoundthatthediffractionfieldsetsinafingerprintofthetopographiceffectinthetotalgroundmotions.Theseconclusionsarefurthersupportedbyobservationsinthetime-domainintermsofsnapshotsofthepropagationpatternsoverthecompletecomputationalmodel.Inthissensethegeometricsingularitiesareclearlyidentifiedassourcesofdiffractionandfortheconsideredrangeofdimensionlessfrequenciesitisevidentthatlargeramplificationsareobtainedforthegeometriescontainingalargernumberofdiffractionsourcesthusresultinginastrongertopographiceffect.Theneedforclosed-formsolutionsofcanonicalproblemstoconstructarobustanalysismethodbasedonthediffractionfieldisidentified.
简介:Inthispaper,amathematicalmodelforLovewavepropagationinaporouselasticlayerunderarigidboundaryrestingoveraporo-elastichalf-spacehasbeendeveloped.ThestudyshowsthatsuchamediumtransmitstwotypesofLovewaves.ThefirstfrontdependsonthechangeinvolumefractionoftheporeswhereasthesecondfrontdependsuponthemodulusofrigidityoftheelasticmatrixofthemediumandisthesameastheLovewaveinanelasticlayeroveranelastichalf-space.Itisobservedthatthefirstfrontismanytimesfasterthantheshearwaveinthemediumwithvoidporesduetothechangeinthevolumefractionoftheporesandissignificant.
简介:在精力平衡实验期间,patch-to-patch灌溉在一块纵贯的面向的棉花地里在土壤潮湿产生了坡度。从相对干燥的在上游的补丁由于强壮的水平移流开发相对弄湿下游的补丁的内部边界层(IBL)与占优势的在北方的风联系了。这产生了多重尺寸的大旋涡,它在IBL在骚乱的结构上有重要影响。在IBL以内在二高度测量的风速度,温度,湿度,和精力流动的力量系列和cospectra被介绍并且过去常在表面层骚乱上调查IBL的影响。系列和cospectra被外部骚乱极大地在低频率提高。这些骚乱的山峰频率没随着高度变化。系列和cospectra典型地收敛了并且与在高频率的堪萨斯光谱平行(在惯性的子域)。当表面层是稳定的时,在水平风速度的系列的清楚的差距在中间的频率存在。结果显示在在上游的对流边界层发源的大旋涡在表面层骚乱的系列和cospectra上有可观的影响。这些大旋涡的影响更大(1)当IBL比IBL什么时候没存在在近的表面层是开发得好的时,(2)在比在底层高级,并且(3)当大气的表面层(ASL)比ASL什么时候是稳定的不稳定时。这些大旋涡的长度规模与在实验地点的表面异质的主导的规模一致。
简介:Freevibrationproblemsoflatticesandwichbeamsunderseveraltypicalboundaryconditionsareinvestigatedinthepresentpaper.Thelatticesandwichbeamistransformedtoanequivalenthomogeneousthree-layeredsandwichbeam.Unlikethetraditionalanalyticalmodelinwhichtherotationanglesofthefacesheetsandthecoreareassumedthesame,diferentrotationanglesareconsideredinthispapertocharacterizetherealresponseofsandwichbeams.Theanalyticalsolutionsofthenaturalfrequenciesforseveraltypicalboundaryconditionsareobtained.Theefectsofmaterialpropertiesandgeometricparametersonthenaturalfrequenciesarealsoinvestigated.
简介:Basedonconsolidationequationsproposedforunsaturatedsoil,ananalyticalsolutionfor1Dconsolidationofanunsaturatedsingle-layersoilwithnonhomogeneousmixedboundaryconditionisdeveloped.Themixedboundaryconditioncanbeusedforspecialapplications,suchastestsoccurinlaboratory.Theanalyticalsolutionisobtainedbyassumingallmaterialparametersremainconstantduringconsolidation.Inthederivationoftheanalyticalsolution,thenonhomogeneousboundaryconditionisfirsttransformedintoahomogeneousboundarycondition.Then,theeigenfunctionandeigenvaluearederivedaccordingtotheconsolidationequationsandthenewboundarycondition.Finally,usingthemethodofundeterminedcoefficientsandtheorthogonalrelationoftheeigenfunction,theanalyticalsolutionforthenewboundaryconditionisobtained.Thepresentmethodisapplicabletovarioustypesofboundaryconditions.Severalnumericalexamplesareprovidedtoinvestigatetheconsolidationbehaviorofanunsaturatedsingle-layersoilwithmixedboundarycondition.
简介:TheexistenceandmultiplicityofpositivesolutionsarestudiedforaclassofquasilinearellipticequationsinvolvingSobolevcriticalexponentswithmixedDirichlet-Neumannboundaryconditionsbythevariationalmethodsandsomeanalyticaltechniques.
简介:Itiswidelyacceptedthatinaturbulentboundarylayer(TBL)withadversepressuregradient(APG)anouterpeakusuallyappearsintheprofileofstreamwiseReynoldsstress.However,theeffectofAPGonthisouterpeakisnotclearlyunderstood.Inthispaper,theeffectofAPGisanalysedusingthenumericalandexperimentalresultsintheliterature.BecausetheeffectofupstreamflowisinherentintheTBL,wefirstanalysethiseffectinTBLswithzeropressuregradientonflatplates.Undertheindividualeffectofupstreamflow,anouterpeakalreadyappearsintheprofileofstreamwiseReynoldsstresswhentheTBLcontinuesdevelopinginthestreamwisedirection.TheAPGacceleratestheappearanceoftheouterpeak,insteadofbeingatrigger.
简介:structure-foundation-soil的考虑动态相互作用是在原子力量设备的地震安全的评估的一个基本要求。一个有效、精确的动态相互作用在时间领域的数字模型成为了当前的研究的一个重要话题。在这研究,放大边界有限元素方法(SBFEM)与好申请前景用作一条有效数字途径被改进。这个方法有几个优点,包括维数减小,光线的分析答案的精确性,和不同其它边界元素方法,它不要求一个基本答案。这研究集中于证实高效放大了边界在时间领域的有限元素相互作用分析模型基于加速单位推动反应矩阵,在哪个几种新溶液技术,例如一个无尺寸的方法到解决相互作用力量,被使用改进实际土壤参数的数字稳定性并且减少计算的数量。最后,领域方法被原子力量结构和算法的精确性的反应说明的时间的可行性被比较动态地与一个大规模粘弹性的土壤模型的精炼验证。
简介:Westudyboundaryvalueproblemsforfractionalintegro-differentialequationsinvolvingCaputoderivativeoforderα∈(n-1,n)inBanachspaces.ExistenceanduniquenessresultsofsolutionsareestablishedbyvirtueoftheHolder'sinequality,asuitablesingularGronwall'sinequalityandfixedpointtheoremviaaprioriestimatemethod.Atlast,examplesaregiventoillustratetheresults.