简介:Asanefficienttoolinhandlinguncertainissues,Dempster-Shaferevidencetheoryhasbeenincreasinglyusedinstructuralhealthmonitoringanddamagedetection.Inapplications,however,Dempster-Shaferevidencetheorysometimesleadstocounter-intuitiveresults.Inthisstudy,anewfusionalgorithmofevidencetheoryisputforwardtoaddressvariouscounter-intuitiveproblemsandmanagethereliabilitydifferenceoftheevidence.Theproposedalgorithmcomprisesthefollowingaspects:(1)Dempster’scombinationruleisgeneralizedbyintroducingtheconceptofevidenceullage.ThenewruleallowsclassicalDempster’sruleandcanresolvecounter-intuitiveproblemscausebyevidenceconflictandevidencecompatibility;(2)areliabilityassessingmethodbasedonaprioriandposteriorknowledgeisproposed.Comparedwithconventionalreliabilityassessment,theproposedmethodcanreflecttheactualevidencereliabilitiesandcanefficientlyreducedecisionrisk.Numericalexamplesconfirmthevalidityandutilityoftheproposedalgorithm.Inaddition,anexperimentalinvestigationonaspatialtrussstructureiscarriedouttoillustratetheidentifiedabilityoftheproposedapproach.Theresultsindicatethatthefusionalgorithmhasnostrictrequestontheaccuracyandconsistencyofevidencesourcesandcanefficientlyenhancediagnosticaccuracy.
简介:没有硬连线的连接,高精力的灯激活的opto机电的致动器的一种photostrictive类型能介绍使活动和控制效果。这份报纸经由photostrictive致动器在板结构的无线颤动控制探讨可控制性方面。一个形式的力量索引,考虑了致动器的模式数字,空间分发,和尺寸,被选择为客观功能决定photostrictive致动器的最佳的地点。线性方法论在这篇论文被建议,颤动方程在标准州空间的形式被写。基于的编码二进制代码的GA联合了最佳的放置和LQR(线性二次的管理者)控制计划被合并了,它最大化形式的力量索引,抑制的关上的环并且最小化输入光紧张到致动器。在现在的方法,三个仅仅weighting因素被用来用GA寻找最佳的Q和R矩阵,它减少染色体长度并且因此最小化计算时间。数字结果证明战略上放的致动器补丁的使用能有效地控制统治结构的颤动的基本模式。
简介:Evolutionarycomputationbasedontheideaofbiologicevolutionisonetypeofglobaloptimizationalgorithmthatusesself-adaptation,self-organizationandrandomsearchingtosolveoptimizationproblems.Theevolutionary-simplexalgorithmisintroducedinthispaper.Itcontainsfloatingencodingwhichcombinestheevolutionarycomputationandthesimplexalgorithmtoovcrcomctheproblemsencounteredinthegeneticalgorithmandevolutionarystrategymethods.Numericalcxpcrimcntsarcperformedusingseventypicalfunctionstoverifythealgorithm.Aninverseanalysismethodtoidentifystructuralphysicalparametersbasedonincompletedynamicresponsesobtainedfromtheanalysisinthetimedomainisprcscntcdbyusingtheevolutionary-simplexalgorithm.Themodalevolutionary-simplexalgorithmconvertedfromthetimedomaintothemodaldomainisproposedtoimprovetheinverseefficiency.Numericalcalculationsfora50-DOFsystemshowthatwhcncomparedwithothermethods,theevolutionary-simplexalgorithmoffersadvantagesofhighprecision,cfficientsearchingability,strongabilitytoresistnoise,independenceofinitialvalue,andgoodadaptationtoincompleteinformationconditions.
简介:OnJune22,1518,alargeearthquake,measuringM71/2,occurredoffshorewestofSeoul,KoreainthesouthernYellowSea.ThisearthquakeaffectedthewholeKoreanPeninsula,andcauseddamagetothecoastalareassuchasSeoul,wheretheseismicintensitywasdegreeⅧ.Aftershockactivitylastedformorethanonemonth.TheearthquakealsoaffectedtheEasternChinaregion.ThisearthquakewaspossiblyrelatedtotheactivityofthewesternmarginfaultzoneoftheKoreanPeninsula(theeasternmarginfaultzoneofthesouthernYellowSea).Theepicenteroftheearthquakewaslocated36.5°Nand125.2°E.
简介:Thefireworkalgorithm(FWA)isanovelswarmintelligence-basedmethodrecentlyproposedfortheoptimizationofmulti-parameter,nonlinearfunctions.NumericalwaveforminversionexperimentsusingasyntheticmodelshowthattheFWAperformswellinbothsolutionqualityandefficiency.WeapplytheFWAinthisstudytocrustalvelocitystructureinversionusingregionalseismicwaveformdataofcentralGansuonthenortheasternmarginoftheQinghai-Tibetplateau.Seismogramsrecordedfromthemomentmagnitude(MW)5.4Minxianearthquakeenableobtaininganaveragecrustalvelocitymodelforthisregion.WeinitiallycarriedoutaseriesofFWArobustnesstestsinregionalwaveforminversionatthesameearthquakeandstationpositionsacrossthestudyregion,invertingtwovelocitystructuremodels,withandwithoutalow-velocitycrustallayer;theaccuracyofouraverageinversionresultsandtheirstandarddeviationsrevealtheadvantagesoftheFWAfortheinversionofregionalseismicwaveforms.WeappliedtheFWAacrossourstudyareausingthreecomponentwaveformdatarecordedbyninebroadbandpermanentseismicstationswithepicentraldistancesrangingbetween146and437km.Theseinversionresultsshowthattheaveragethicknessofthecrustinthisregionis46.75km,whilethicknessesofthesedimentarylayer,andtheupper,middle,andlowercrustare3.15,15.69,13.08,and14.83km,respectively.ResultsalsoshowthattheP-wavevelocitiesoftheselayersandtheuppermantleare4.47,6.07,6.12,6.87,and8.18km/s,respectively.
简介:Weappliedthedouble-differenceearthquakerelocationalgorithmto1348earthquakeswithM_S≥2.0thatoccurredinthenorthernTianshanregion,Xinjiang,fromApril1988toJune2003,usingatotalof28701P-andS-wavearrivaltimesrecordedby32seismicstationsinXinjiang.AimingtoobtainmostoftheseM_S≥2.0earthquakesrelocations,andconsideringtherequirementsoftheDDmethodandtheconditionofdata,weaddedthetraveltimedataofanother437earthquakeswith1.5≤M_S<2.0.Finally,weobtainedtherelocationresultsfor1253earthquakeswithM_S≥2.0,whichaccountfor93%ofallthe1348earthquakeswithM_S≥2.0andincludesalltheM_S≥3.0earthquakes.Thereasonfornotrelocatingthe95earthquakeswith2.0≤M_S<3.0isanalyzedinthepaper.Afterrelocation,theRMSresidualdecreasedfrom0.83sto0.14s,theaverageerroris0.993kminE-Wdirection,1.10kminN-Sdirection,and1.33kminverticaldirection.Thehypocenterdepthsaremoreconvergentthanbeforeanddistributedfrom5kmto35km,with94%beingfrom5kmto35km,68.2%from10kmto25km.Theaveragehypocenterdepthis19km.
简介:Wepresentaparallelhybridalgorithmbasedonpseudospectralmethod(PSM)andfinitedifferencemethod(FDM)fortwo-dimensional(2-D)globalSHwavefieldsimulation.Thewhole-EarthmodelistakenasacrosssectionofsphericalEarth,andcorrespondingwaveequationsaredefinedin2-Dcylindricalcoordinates.SpatialderivativesinthewaveequationsareapproximatedwithefficientandhighaccuracyPSMinthelateralandhigh-orderFDMintheradialdirectiononstaggeredgrids.Thisalgorithmallowsustodividethewhole-Earthintosub-domainsinradialdirectionandimplementefficientparallelcomputingonPCcluster,whileretainshighaccuracyandefficiencyofPSMinlateraldirection.Atransformationofmomenttensorbetween3-DsphericalEarthandour2-Dmodelwasproposedtogivecorrespondingmomenttensorcomponentsusedin2-Dmodeling.Comparisonofmodelingresultswiththoseobtainedbydirectsolutionmethodshowsverygoodaccuracyofouralgorithm.Wealsodemonstrateitsfeasibilitywithalateralheterogeneouswhole-Earthmodelwithlocalizedvelocityperturbation.
简介:基础孤立的结构被发现了在在由于可以在近来源的地面运动存在的长时期脉搏的近差错的区域的风险。包括被动、活跃、半活跃的控制系统,各种各样的控制策略被调查了克服这个问题。这研究基于在相应于各种各样的地震危险层次的摇晃的地面的不同层次期间从一座孤立的大楼期望的几个性能层次集中于一个半活跃的控制算法的开发。建议基于表演的算法基于著名半活跃的skyhook控制算法的一个修改版本。取决于摇晃的水平的控制获得在结构上强加了的建议控制算法变化。建议控制系统用在受到七个放大地面运动记录的一座基础孤立的基准大楼上执行的一系列分析被评估了。模拟结果证明最新建议的算法在改善是有效的结构并且为选择地震的大楼的nonstructural性能。
简介:BasedonthewaveformdataobservedbytheregionalseismicnetworkofGansuProvince,wecalculatedtheapparentstressof422earthquakeswithM_L≥2.0occurringinthesurroundingareaoftheMinxianearthquakefromJanuary2010toJuly2014andobtainedthetemporalandspatialvariationofapparentstressbeforeandaftertheMinxianearthquake.Resultsshowthat(1)thehighvalueofapparentstressofearthquakeswithM_L≥4.0wasconcentratedintheepicenterareabeforetheMinxianearthquakewhilethatofearthquakeswithM_L<4.0wasnot;(2)ApparentstressaroundtheepicenterareashowedanobviousincreasingprocessbeforetheMinxianearthquakeandtheincreasingprocesshascontinuedafterthemainshock,whichmeansthatthisstudyareaisstillinthedangerofstrongearthquakes.
简介:OnJuly22,2013,theMinxian-ZhangxianM_S6.6earthquakeoccurredontheeastsegmentofLintan-Dangchangfault.TheanalysisofdigitalelevationandremotesensingimagingshowsthattheeastsegmentofLintan-Dangchangfaultisstillactiveandthemainthrustfeatureofthefaultswitchestoleftlateralslip.Withthefieldresearchofintensityanddamage,severalabnormalareasofdegreeⅧspreadintheisoseismallineofdegreeⅦandsomeabnormalareasofdegreeⅦspreadintheisoseismallineofdegreeⅥ.Theseabnormalareasaredistributedalongthehangingwallofthefaultinawidthof2km.TheanalysisbasedontheremotesensinganddigitalelevationmodelshowsthatthesegmentoftheLintan-DangchangfaultsouthofMinxianmainlyslipsinleftliteral.Thefaultmovementmadethesoilsoftinthefaultzone.Theearthquakemotionpropagatedalongthefaultzone.Thereforethestrongearthquakemotioncausedfoundationfailureinthesoftsoilalongthefaultzoneandtheabnormalintenseareasofdisasterformed.