简介:§1.IntroductionThedeterminationoftheRamseynumbersisamainprobleminthestudyofthecombinatorialmathematicsandgraphtheory.However,itisstillaverydifficultunsolvedproblemtodate.HenceevaluationofthelowerboundoftheRamseynumbersseems(tobe)verynecessary.Abbott,H.L.[1]showedthataspecialformulaofthelowerboundoftheRamseynumbers:R(2~n+1,2~n+1)≥5~n+1.Erd(o|¨)s,P.andSpencer,J.[2]obtainedthataformulaofthelowerboundoftheRamseynumbersR(s,t)
简介:AsetofnpointsintheplanedeterminesatotalCn^2distances(someofthemmaybethesame).Letrnbetheratioofthemaximumdistancetotheminimumdistance,andRnbethegreatestlowerboundforrn.ByusingthemathematicalsoftwareMathematica,theauthorgetsthefollowingresultsinthispaper.R12≤2.99496…,R13≤cscπ/10.
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简介:Inthispaper,weproposeanewbranchandboundalgorithmforthesolutionoflargescaleseparableconcaveprogrammingproblems.Thelargestdistancebisection(LDB)techniqueisproposedtodividerectangleintosub-rectangleswhenoneproblemisbranchedintotwosubproblems.ItisprovedthattheLDBmethodisanormalrectanglesubdivision(NRS).Numericaltestsonproblemswithdimensionsfrom100to10000showthattheproposedbranchandboundalgorithmisefficientforsolvinglargescaleseparableconcaveprogrammingproblems,andconvergencerateisfasterthanω-subdivisionmethod.
简介:让T是在一个Banach空格的一个围住的线性操作符,与蟽(T)={1}。In1983,Esterle-Berkani's推测为差别的腐烂被建议(我—T)T~n如下:任何一个liminf_(n→∞)(n+1)‖(信息技术)T~n‖≥1/e或T=我。我们证明这个主张并且讨论一些它的后果。
简介:Theplasticload-bearingcapacityofductilecompositessuchasmetalmatrixcompositesisstudiedwithaninsightintothemicrostructures.Themacroscopicstrengthofacompositeisobtainedbycombiningthehomogenizationtheorywithstaticlimitanalysis,wherethetemperatureparametermethodisusedtoconstructtheself-equilibriumstressfield.Aninterfacefailuremodelisproposedtoaccountfortheeffectsoftheinterfaceonthefailureofcomposites.Thestaticlimitanalysiswiththefinite-elementmethodisthenformulatedasaconstrainednonlinearprogrammingproblem,whichissolvedbytheSequentialQuadraticProgramming(SQP)method.Finally,themacroscopictransversestrengthofperforatedmaterials,themacroscopictransverseandoff-axisstrengthoffiber-reinforcedcompositesareobtainedthroughnumericalcalculation.Thecomputationalresultsareingoodagreementwiththeexperimentaldata.
简介:团体心理训练(Outward—boundTraining)是一种塑造团队?激发个人成长的教学模式,通过对真实情景的模拟,以体验?启发为基本手段,目的是引导参与者将体会到训练项目中所蕴含的深刻道理与理念,同化到潜意识当中,最终体现于外在的人格?现如今这个竞争激烈的社会当中,拥有拥有良好的团队精神和积极进取的人生态度,是塑造现代人格特质的两大核心内涵?
简介:为Sierpinski垫板,由使用由特殊常规等边六角形组成的一种盖子,我们定义等价于Hausdorff措施的一项新措施并且获得这项措施更在下固定。而且,theSierpinski垫板的Hausdroff措施的下列更低的界限被完成了H~s≥0.670432在S表示Sierpinski垫板的地方,s=dim_H=log_23,和H~s表示S的s维的Hausdorff措施。上述结果改进发展了在那[2]。
简介:Withsolidphaseorganicsynthesismethod(SPOS),polymer-boundN-enoylprolinol(4)waspreparedbytheattachmentofN-enoylprolinol(3)toMerrifieldresinandwasusedforasymmetricMichaeladditionsforthefirsttime.Theenantiomericexcessobtainedbythismethodisincreasedascomparedwiththatobtainedbythecorrespondingsolutionphasereactions.
简介:ThesymmetricGalerkinboundaryelementmethod(SGBEM)insteadofthefiniteelementmethodisusedtoperformlowerboundlimitandshakedownanalysisofstructures.Theself-equilibriumstressfieldsareconstructedbyalinearcombinationofseveralbasicself-equilibriumstressfieldswithparameterstobedetermined.Thesebasicself-equilibriumstressfieldsareexpressedaselasticresponsesofthebodytoimposedpermanentstrainsandobtainedthroughelastic-plasticincrementalanalysis.Thecomplexmethodisusedtosolvenonlinearprogramminganddeterminethemaximalloadamplifier.Thelimitanalysisistreatedasaspecialcaseofshakedownanalysisinwhichonlytheproportionalloadingisconsidered.ThenumericalresultsshowthatSGBEMiseffcientandaccurateforsolvinglimitandshakedownanalysisproblems.