简介：Thispaperstudiesthetemporalandspatialdistributionofgreatglobalearthquakes(MW≥8.0)since1900.Wecomparethetwoperiodsofupsurgesofgreatearthquakesoccurringinthemiddleoflastcenturyandbeginningofthiscentury.Theformerperiodtookplacebetween1950and1965duringwhich13greatearthquakes(MW≥8.0)occurred,includingthreeeventswithmomentmagnitudegreaterthan9.0.Thelargestmagnitudeinthisperiodreached9.6.Thelatterperiodstartsfromthebeginningofthiscentury.Inlessthan12years,15greatearthquakeshaveattackedtheworldwiththelargestmagnitudebeingMW9.1.Onthebasisofcomparisonbetweenthesetwoupsurgesofglobalearthquakeactivity,weinferthattheongoinghighlevelofearthquakeactivitymaycontinueforanotherfiveyearsorso.Numerousgreatearthquakes(MW≥8.0)andmanylargeearthquakes(MW6.0~7.0)willoccurgloballyinthesefiveyears.Inaddition,thispaperalsodiscussestherelationshipsbetweenearthquakeactivityalongtheSumatrasegmentoftheIndian-AustraliaplateboundaryandthatintheBayankalablockinthemiddleofQinghai-Tibetanplateauaswellasintheblocksofthesouthernplateau.TheresultsindicatethattheQinghai-Tibetanplateau,inparticularitsmiddleandsouthernparts,isalikelyplaceforfutureearthquakesofmagnitudeover7.0.

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简介：Thispaperreviewedthemaintarget,functions,tool(OpenQuakesoftware)andresearchachievementsoftheGlobalEarthquakeModel(GEM)Foundation,andmadeasimpleprospectonthedevelopmentandapplicationofprojectsofGEMinthefuture.LearningfromGEMandOpenQuakeishelpfultoimprovetheseismichazardmodelofChinaandenhancethescientificityoftheseismichazardassessmentformetropolitansandmajorengineeringfacilitiesnearmajorseismogenicstructures.

简介：为形式的闲差事分析过程，模特儿由Ghobarah等求婚了。(此后打电话给G模特儿，1999)被扩大了说明对充分的理由运动激动的结构的全球地震损坏的短暂更高的模式的贡献。建议模型身体上并且完美地衔接了G模型，最后的弄软模特儿由DiPasquale和Cakmak(1988)求婚了。相应于所有考虑颤动模式的形式的损坏索引被CQC规则或SRSS规则联合。增长动态分析(IDA)在三个例子RC框架上被执行验证建议模型，并且全面比较被执行。示范显示建议模型是安逸的实现并且在结构的损坏进化上在短暂颤动时期和模式反映转变的影响。与建议模型联系的一些限制也被探讨。进一步试验性的确认被需要以后改进模型。

简介：Inthispaperwepresentacomparativeanalysisofglobalfrequencyandlocaldeformationdataforalargeconcretebridge.Theasymptoticprobabilitydistributionsofthecentralstatisticsarepresented,andcomparedwithempiricalbootstrapestimates.Bootstrappeddistributionsarecalculatedfromreferencedataobtainedduring1999-2000andusedtodevelopchange-pointalarmcriteriaforthestructure,usingreasonablesensitivitymeasuresdevelopedfromFEMsimulationsandstructuralanalysis.Theimplicationsofthefrequencydataarediscussedinconjunctionwiththestrainanddisplacementmeasurementsinordertodiscerniftheloadcarryingcapacityofthebridgehasbeenaffected.Thecriticalneedformoreadvancedtemperaturecompensationmodelsforlargestructurescontinuallyinthermaldisequilibriumisdiscussed.

简介：WecompilearegionalcatalogueofearthquakeswithmomentmagnitudeoftheCenter-SouthernAsiatestarea(20°-35°N,85°-105°E)fortheGlobalSeismicHazardAssessmentProgram(GSHAP).Therearesignificantinhomogeneousanduncompleteddata,andnuniformityofearthquakemagnitudesinthistestareabecausethisregionissituatedontheboundariesofmanycountries,suchasChina,India,Nepal,Vietnam,etc.WeestablisharelationshipbetweenGutenbergsurface-wavemagnitudeandIASPEIsurface-wavemagnitude,whichcanbeusedforconversionofdifferentmagnitudescalesintomomentmagnitudeforthiscatalogue.AcatalogueofeventswithMw≥6.0ofthistestareaisgivenattheendofthispaper.

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.

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简介：TheprimarygoalofthedemonstrationprojectendorsedbytheScientificandTechnicalCommitteeforIDNDRin1992istoensurethatnationalagenciesareabletoassessseismichazardinaregionallycoordinatedfashionbyusingadvancedmethods.China,asaRegionalCenterofCentralSouthernAsia,hascontactedwithcountriesoftheregiontorealisticallypracticeseismichazardassessmentsofContinentalAsia.AtestarealocatedinthecollisionboundarybetweentheIndianandEurasianplateswaschosentoexaminetheseismichazardassessmentapproachintheregionalcoordinates.TheseismotectonicsandthreeversionsofseismicsourcesofthetestareaaredescribedinthispaperandundertheGlobalSeismicHazardAssessmentProgram(GSHAP),guidelinesanearthquakecatalogueofthetestareawasassembled.Becauseoftheincompletenessofearthquakedataindifferentcountries,weadoptdifferenttimewindowsfordifferentmagnitudeintervalsinordertoobtaintheseismicityparametersofsources.Byu