简介:Tworocksampleswithdifferentstructuresandmaterialsweredeformedunderabiaxialloadingsystem,andmulti-pointstrainmeasurementswereperformedforeachsample.ThedistributionofstrainanomaliesduringthedeformationandtheinstabilityprocesswereanalyzedbyusingCvvalueputforwardbyWANGXiao-qingandCHENXue-zhong,etal,aparametertodescribetheheterogeneousdistributionofearthquakeprecursors,soastoexaminethemethodofCvvalueandtoexploreitsphysicalmeaningexperimentally.TheresultshowsthatthechangeofCvvalueiscorrelatedtothechangeofdeformationcharacteristicsandisaneffectiveparametertodescribetheheterogeneityofprecursordistribution.Cvvalueincreasesfirstlyandthendecreasesbeforetheinstability,andtheinstabilityoccurswhenCvvaluedecreasestothelevelbeforeincreasing.ThisindicatesthatCvvaluemaybeausefulparameterforearthquakeprediction.
简介:Evolutionarycomputationbasedontheideaofbiologicevolutionisonetypeofglobaloptimizationalgorithmthatusesself-adaptation,self-organizationandrandomsearchingtosolveoptimizationproblems.Theevolutionary-simplexalgorithmisintroducedinthispaper.Itcontainsfloatingencodingwhichcombinestheevolutionarycomputationandthesimplexalgorithmtoovcrcomctheproblemsencounteredinthegeneticalgorithmandevolutionarystrategymethods.Numericalcxpcrimcntsarcperformedusingseventypicalfunctionstoverifythealgorithm.Aninverseanalysismethodtoidentifystructuralphysicalparametersbasedonincompletedynamicresponsesobtainedfromtheanalysisinthetimedomainisprcscntcdbyusingtheevolutionary-simplexalgorithm.Themodalevolutionary-simplexalgorithmconvertedfromthetimedomaintothemodaldomainisproposedtoimprovetheinverseefficiency.Numericalcalculationsfora50-DOFsystemshowthatwhcncomparedwithothermethods,theevolutionary-simplexalgorithmoffersadvantagesofhighprecision,cfficientsearchingability,strongabilitytoresistnoise,independenceofinitialvalue,andgoodadaptationtoincompleteinformationconditions.
简介:这个地点和结构的参数无常的动态效果的考虑被标准在大多数国家为核电厂(NPP)要求。抗地震的标准提供二个基本方法分析参数无常。手工地直接处理计算地板反应系列(皇家学会会员)确定的途径珍视是第一个方法。第二个方法是执行概率统计的FRS的分析根据蒙特卡罗方法结果。二个方法能仅仅反映不明确的参数的全面效果,并且结果不能为某个参数影响和贡献被屏蔽。在这研究,基于NPP的地板反应系列的动态分析,为各种各样的不明确的参数的估计的影响的一个全面索引被介绍并且推荐,包括关联系数,回归斜坡系数和旋风秋千。在NPP地震标准补偿指导的缺乏,建议方法能有效地被用来从敏感,尖酸和统计秋千的方面评估各种各样的参数的贡献关联。最后,例子被提供从系统、直觉的观点验证指示物的集合,例如NPP的皇家学会会员的结构参数和贡献的影响的无常。这个索引对参数的不同类型敏感,它为评估为NPP要求的抗地震的参数提供一种新技术。