简介：我们由使用nonstationary多项式试穿(NPF)为地震噪音变细建议一个新奇方法，它能沿着事件与振幅变化估计协调部件。有变化时间的系数的NPF能适应地估计协调部件。多项式系数的光滑被塑造规则化控制。信号沿着在一个普通中点(CMP)的偏移量轴是协调的在正常moveout(NMO)以后的集合。我们使用NPF估计有效信号并且从而稀释随机的噪音。为象地面转动那样的光线的像事件的噪音，我们首先采用光线的踪迹(RT)转变数据到时间速度域的变换。然后，NPF被用来在RT领域估计协调噪音。最后，协调噪音适应地从吵闹的数据集被减去。建议方法能有效地沿着事件与振幅变化估计协调噪音，没有需要建议那个噪音振幅是不变的。结果合成并且域数据例子证明与象静止多项式适合和低切割过滤器那样的常规方法相比，建议方法能有效地压制地震噪音并且保存信号。

简介：ThedatarecordedduringthesitesurveyintheZhangzhouareainFujianProvincebetweenOctober23,2007andDecember3,2007wasanalyzed.Themainmethodsadoptedforthenoiselevelofthisareaarethenoiserootmeansquare(RMS),noisepowerspectrumdensityandnoisecoherencyfunction.Theresultsindicatethatthenoiselevelsofthesurveysitesarehigherinthe1s-10speriods,whichisthemainfrequencybandofpreliminarymicroseism,andalso,twomainnoisesourceswerefoundin1.5Hzandaround5Hz.Accordingtoarithmetic,thedirectionandfrequencybandofthenoisesourcewereanalyzedandacademicproofswerepresented.Atlast,wefoundthatthenoisesourcein1.5Hzwasmadebythewaterwavearousedbythewindinthereservoirregionandthenoisesourcearound5Hzwasmadebythepowerstationinthenortheastdirection

简介：Thenoisedatainverticalcomponentrecordsof85seismicstationsinFujianProvinceduring2012isusedastheresearchobjectinthispaper.Thenoisedataisdividedintofiveminutesegmentstocalculatethepowerspectra.Thehighreferencelineandlowreferencelineofstationarethenidentifiedbydrawingaprobabilitydensityfunctiongraph(PDF)usingthepowerspectralprobabilitydensityfunction.Moreover,accordingtotheanomaliesofPDFgraphsin85seismicstations,theabnormalnoiseisdividedintofourcategories:droppedpacket,lownoise,highnoise,andmediannoiseanomalies.Afterwards,fourselectionmethodsarefoundbythehighorlownoisereferencelineofthestations,andthesystemofreal-timemonitoringofseismicnoiseisformedbycombiningthefourselectionmethods.Noiserecordsof85seismicstationsinFujianProvinceinJuly2013areselectedforverification,andtheresultsshowthattheanomalousnoise-recognitionsystemcouldreacha90%successrateatmoststationsandtheeffectofselectionareverygood.Therefore,itcouldbeappliedtotheseismicnoisereal-timemonitoringinstations.

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简介：Laboratoryexperimentsandfieldobservationsshowthattheequilibriumrangeofwindwavespectrapresentsa–4powerlawwhenitisscaledproperly.Thisfeaturehasbeenattributedtoenergybalanceinspectralspacebymanyresearchers.Inthispaperwepointoutthatwhitenoiseonanoscillationsystemcanalsoleadtoasimilarinversepowerlawinthecorrespondingdisplacementspectrum,implyingthatthe–4powerlawfortheequilibriumrangeofwindwavespectramayprobablyonlyreflecttherandomicityofthewindwavesratherthananyotherdynamicalprocessesinphysicalspace.Thisexplanationmayshedlightonthemechanismofotherphysicalprocesseswithspectraalsoshowinganinversepowerlaw,suchasisotropicturbulence,internalwaves,etc.

简介：Themotionofabubblenearthefreesurfaceissolvedbytheboundaryelementmethodbasedonthelinearwaveequation,andtheinfluenceoffluidcompressibilityonbubbledynamicsisanalyzed.Basedonthesolutionofthebubblemotion,thefar-fieldradiationnoiseinducedbythebubbleiscalculatedusingKirchhoffmovingboundaryintegralequation,andtheinfluenceoffreesurfaceonfar-fieldnoiseisresearched.Astheresults,theoscillationamplitudeofthebubbleisweakenedincompressiblefluidcomparedwiththatinincompressiblefluid,andthefreesurfaceamplifiestheeffectoffluidcompressibility.Whenthedistancebetweenthebubbleandanobserverismuchlargerthanthatbetweenthebubbleandfreesurface,thesharpwavetroughofthesoundpressureattheobserveroccurs.Withtheincrementofthedistancebetweenthebubbleandfreesurface,thetimeofthewavetroughappearingisdelayedandthevalueofthewavetroughincrease.Whenthedistancebetweentheobserverandthebubbleisreduced,thesharpwavetroughattheobserverdisappears.

简介：Astochastictwo-dimensionalFornasini-Marchesini'sModelⅡ(2-DFMMⅡ)withmultiplicativenoiseisgiven,andafilteringalgorithmforthismodel,whichisoptimalinthesenseoflinearminimum-variance,isdeveloped.Thestochastic2-DFMMⅡwithmultiplicativenoisecanbereducedtoa1-Dmodel,andtheproposedoptimalfilteringalgorithmforthestochastic2-DFMMⅡwithmultiplicativenoiseisobtainedbyusingthestateestimationtheoryof1-Dsystems.Anexampleisgiventoillustratethevalidityofthisalgorithm.

简介：TheeffectsofmagnituderoundingandofthepresenceofnoiseintheroundedmagnitudesontheestimationoftheGutenberg–Richterb-valueareexplored,andthewaystocorrectfortheseeffectsareproposed.Fortypicalvalues,b=1androundingintervalDM=0.1,theroundingerrorisapproximately-10-3anditcanbecorrectedtoanegligibleapproximately-10-5.Forthesametypicalvalues,theeffectofnoisecanbelarger,dependingonthecharacteristicsofthenoisedistribution;fornormallydistributednoisewithstandarddeviationr=0.1,thecorrectb-valuemaybeunderestimatedbyafactor*0.97.

简介：小浪变换成功地在在本地时间与他们的能力处理的地震数据被使用了—频率分析。然而，因为小浪变换系数揭示仅仅三空间取向，directionality的鉴定被限制。而山脉让，变换为与线性地改变特征处理信号的方向察觉和能力有一个优异能力。在这篇论文，我们在场基于山脉处理的地震数据让的低signal-to-noise比率(SNR)的问题转变。有从华南的低SNR的实际地震数据用让的山脉被处理了改进SNR和地震事件的连续性的变换。结果证明让的山脉转变比对这些任务的小浪变换好。

简介：Thestudyiscarriedoutontheeffectofdrillingnoiseandvibrationongrowthofgrasscarp,MyloparyngodonPiceus,byusingcut-finmarkingmethodinsitu.Comparedwithothermethods,themethodismoreappropriate,foritsoperationissimplerandmoredatamaybeobtainedunderthesamecondition.Theresultsshowthatdrillingnoiseandvibrationhavesignificanteffectonthegrowthofgrasscarp.Criticalequivalentnoiseandvibrationgrade(NleqandVleq)areabout84.4dBand90.2dB,andtheaffectingradiusisabout8.5m.Theeffectofdrillingnoiseandvibrationcouldbeinfluencedbysomefactors,suchasdurationofpollutionandbodyweightofgrasscarp,etc.Grasscarp′sgrowthcouldrapidlyrecoverafterremovingdrillingnoiseandvibration,indicatingthatthedrillingnoiseandvibrationdonotdamagethefishorgansandtheeffectisreversible.Therefore,theeffectmechanismmaybeduetotheactivatingresponseofnon-hearingsystem.

简介：Inthispaper,theanalysismethodofstochasticresponseofpiledoffshoreplatformexcitedbystationaryfilteredwhitenoiseispresented.Withthismethod,thestronggroundmotionisconsideredasthreedirectionstationaryfilteredwhitenoiseprocess,thetheoreticsolutionsofthreespecialintegrationequationsarederivedwiththeresiduetheorem,andtheexpressionofresponsenodaldisplacementsandmemberforcesofoffshoreplatformexcitedbythestationaryfilteredwhitenoiseisputforward.Thestochasticresponseofapiledoffshoreplatformexcitedbythestationaryfilteredwhitenoise,whichislo-cated114.3minwaterdepth,iscomputed.Theresultsarecomparedwiththoseobtainedwiththere-sponsespectrumanalysismethodandthestationarywhitenoisemodelanalysismethod,andthecorre-spondingconclusionisdrawn.

简介：Moststudiesofseismicnoisecross-correlation(NCC)havefocusedonregional/continentalscaleimagingusingempiricalsurface-waveGreen’sfunctionsextractedfromprimary(0.05–0.08Hz)andsecondary(0.1–0.16Hz)microseisms.Inthiswork,wepresenttheNCCresultsathigherfrequencies([0.5Hz)from6monthsseismicnoiserecordedbyalocalarray(*4kmaperture)deployedalongtheCalicofaultintheMojaveDesert,California.BothfastandslowpropagatingwavesareobservedfromtheNCCrecord-sections.WecomparetheNCCsfromsensorpairsthatshareacommonsensorwiththerecordsofaboreholeshotlocatedveryclosetothiscommonsensor.Theresultshowsagoodmatchoftheslowsurface-wavearrivals,indicatingthattheNCCmethodisabletorecoverunbiasedsurface-waveGreen’sfunctionsatlocalscales.Thestrongbody-waveNCCcomponentiscausedbythePwavesgeneratedoffshoreCalifornia.AlongaSW–NEprofileacrossthefault,weobserveapparentP-wavearrivalsandtheirreflections,whichcanbeexplainedbyalow-velocityzone(LVZ)alongtheCalicofault.WecalculatetheLVZwidthtobe*2.3km,andtheP-wavevelocityreductionwithintheLVZtobe*35%.TheseestimatesareconsistentwithotherevidenceforarelativelywideLVZalongtheCalicofault.

简介：Thispaperpresentsanewapproachforattenuatingcoherentnoisein3Dseismicdata.Anadaptivebeamformingwithgeneralizedsidelobecanceller(GSC)designmethodologyisutilizedhereasageneralformoflinearlyconstrainedadaptivebeamformingstructure.Itconsistsofafixedbeamformer,andasignal-blockingmatrixinfrontofanunconstrainedadaptivebeamformer.Considerationfofthecomplexityofthegeometryfor3Dseismicsurvey,the3DbeamformingwithGSCtechniqueisdevelopedwithtwokeypoints:(1)sortingalongazimuthsectionstosimplifytherelationshipbetweentraveltimeandoffsetfrom3Dto2D,and(2)dynamicbinningschemetoavoidthepossiblepoorfoldinginsomeazimuthsections.Bothsimulationresultandrealdataexampleshowthatthenewlydeveloped3DbeamformingwithGSCyieldsmorecredibleresultsatarelativelowcost,sufficientstabilityandgoodresolution.

简介：自从他们为发现和描出的水库经常是必要的，在地震数据加亮并且分析差错和破裂的地质的特征为烃探索和利用是特别地重要的。我们使用保存边的变光滑(EPS)到地震处理并且建议一个很同类的扫描剧降的方法。方法保存地质的特征，高效地消除随机的噪音，获得蘸信息，并且改进识别油和煤气的陷井的精确性。

简介：TheYellowstonevolcanoisoneofthelargestactivevolcanoesintheworld,anditspotentialhazardsdemanddetailedseismologicalandgeodeticstudies.Previousstudieswithtraveltimetomographyandreceiverfunctionshaverevealedalow-velocitylayerinthecrustbeneaththeYellowstonevolcano,suggestingthepresenceofamagmachamberatdepth.Weuseambientseismicnoisefromregionalseismicstationstoretrieveshort-periodsurfacewavesandthenstudytheshallowshearvelocitystructureoftheYellowstoneregionbysurfacewavedispersionanalysis.WefirstobtainedacrustalmodeloftheareaoutsideoftheYellowstonevolcanoandthenconstructedanabsoluteshearwavevelocitystructureincombinationwithreceiverfunctionresultsforthecrustbeneaththeYellowstonevolcano.Thevelocitymodelshowsalow-velocitylayerwithshearvelocityataround1.3km/s,suggestingthatalarge-scalemagmachamberexistsatshallowlevelswithinthecrustoftheYellowstonevolcanicregion.

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简介：Two-monthcontinuouswaveformsof108broadbandseismicstationsinFujianProvinceanditsadjacentareasareusedtocomputenoisecross-correlationfunction(NCF).ThesignalqualityofNCFisimprovedviatheapplicationoftime-frequencyphaseweightedstacking.TheRayleighandLovewavesgroupvelocitiesbetween1s-20saremeasuredonthesymmetricalcomponentoftheNCFwiththemultiplefiltermethod.Morethan5,000Rayleighwavedispersioncurvesandabout4,000Lovewavedispersioncurvesareobtainedandusedtoinvertforgroupvelocitymaps.Thisdatasetprovidesabout50kmresolutionthatisdemonstratedwithcheckerboardtests.Consideringtheoffgreatcircleeffectininhomogeneousmedium,theraypathistracedbasedonthetraveltimefieldcomputedwithafinitedifferencemethod.Theinvertedgroupvelocitymapsshowgoodcorrelationwiththegeologicalfeaturesintheupperandmiddlecrust.TheFuzhoubasinandZhangzhoubasinshowedlowvelocityontheshortperiodgroupvelocitymaps.Onthelongperiodgroupvelocitymaps,thelowvelocityanomalyinthehighheatflowregionnearZhangzhouandclearvelocitycontrastacrosstheZhenghe-Dapufaults,whichsuggeststhattheZhenghe-Dapufaultmightbeadeepfault.

简介：ThevelocitystructureofthecrustbeneathLiaoningprovinceandtheBohaiseainChinawasimagedusingambientseismicnoiserecordedby73regionalbroadbandstations.Allavailablethree-componenttimeseriesfromthe12-monthspanbetweenJanuaryandDecember2013werecross-correlatedtoyieldempiricalGreen'sfunctionsforRayleighandLovewaves.PhasevelocitydispersioncurvesfortheRayleighwavesandtheLovewavesweremeasuredbyapplyingthefrequencytimeanalysismethod.DispersionmeasurementsoftheRayleighwaveandtheLovewavewerethenutilizedtoconstruct2Dphase-velocitymapsfortheRayleighwaveat8–35speriodsandtheLovewaveat9–32speriods,respectively.BothRayleighandLovephase-velocitymapsshowsignificantlateralvariationsthatarecorrelatedwellwithknowngeologicalfeaturesandtectonicsunitsinthestudyregion.Next,phasedispersioncurvesoftheRayleighwaveandtheLovewaveextractedfromeachcellofthe2DRayleighwaveandLovewavephase-velocitymaps,respectively,wereinvertedsimultaneouslytodeterminethe3Dshearwavevelocitystructures.ThehorizontalshearwavevelocityimagesclearlyandintuitivelyexhibitthattheearthquakeswarmsintheHaichengregionandtheTangshanregionaremainlyclusteredinthetransitionzonebetweenthelow-andhigh-velocityzonesintheuppercrust,coincidingwithfaultzones,andtheirdistributionisverycloselyassociatedwiththesefaults.Theverticalshearwavevelocityimagerevealsthatthelowercrustdownwardtotheuppermostmantleisfeaturedbydistinctlyhighvelocities,withevenahigh-velocitythinnerlayerexistingatthebottomofthelowercrustnearMohoincentralandnortherntheBohaiseaalongtheTanlufault,andthesephenomenacouldbecausedbytheintrusionofmantlematerial,indicatingtheTanlufaultcouldbejustastheuprisingchannelofdeepmaterials.

简介：WestudythefeatureofmediachangesbeneaththeZipingpureservoiranddiscusstheprocessofpermeationwiththewaterlevelriseandfallofthereservoirfromJanuary2005toJanuary2008fromambientnoisecrosscorrelationbyusingcontinuousseismicdatarecordedbythestationsofZipingpuseismicnetworkandYZPstation.Amoving-windowcross-spectrumtechniquehasbeenusedtocalculatetherelativeseismicvelocitychangesbetweenstationpairs.Resultsrevealedanobviousrelationshipbetweenrelativeseismicvelocity,andthewaterlevelchangeswithatimedelaythatmaybecausedbypermeationduringthreemainimpoundmentsandtwolargescaledisemboguements.Impoundmentgeneratesafastandlargeimpactonthesuperficiallayer,andthechangesofseismicvelocityistheresultofincreasedpressureandpermeationduringtheimpoundment.Atthefirstimpoundment,themaineffectfactorispressure.Duringthenexttwoprocessofimpoundment,permeationbecomesthemaineffectfactor,affectingthefaultatadepthofabout8km.

简介：Inhighlypopulatedurbancenters,traditionalseismicsurveysourcescannolongerbeproperlyappliedduetorestrictionsinmoderncivilianlifestyles.Theambientvibrationnoise,includingbothmicroseismsandmicrotremor,thougharegenerallyweakbutavailableanywhereandanytime,canbeanidealsupplementarysourceforconductingseismicsurveysforengineeringseismologyandearthquakeengineering.Thisisfundamentallysupportedbyadvanceddigitalsignalprocessingtechniquesforeffectivelyextractingtheusefulinformationoutfromthenoise.Thus,itcanbeessentiallyregardedasapassiveseismicmethod.Inthispaperwefirstmakeabriefsurveyoftheambientvibrationnoise,followedbyaquicksummaryofdigitalsignalprocessingforpassiveseismicsurveys.ThentheapplicationsofambientnoiseinengineeringseismologyandearthquakeengineeringforurbansettingsareillustratedwithexamplesfromBeijingmetropolitanarea.Forengineeringseismologytheexampleistheassessmentofsiteeffectinalargeareaviamicrotremorobservations.Forearthquakeengineeringtheexampleisforstructuralcharacterizationofatypicalreinforcedconcretehigh-risebuildingusingbackgroundvibrationnoise.Byshowingtheseexampleswearguethattheambientnoisecanbetreatedasanewsourcethatiseconomical,practical,andparticularlyvaluabletoengineeringseismologyandearthquakeengineeringprojectsforseismichazardmitigationinurbanareas.