简介：引言无论人们利用三维进行勘探或开发,列出有助于降低评价和钻探过程中风险的手段是有益的,包括那些有助于区分油气和含水层的手毁。对于碎屑岩层序,在盖层和储层之间的声阻抗差异,没有亮点

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简介：应用包括欧洲VLBI网和美国的Haystack在内的VLBI阵，我们于历元1989.75在频率5GHz对类星体3C286进行了观测，在分辨率高达1毫解秒（mas）的图像上。该源的“核”首次被分解为相距大约5.8mas的两个分离；喷流向西南方向延伸并呈正弦状的摆动形态。图像在所能达到的动态范围上没有出现反向喷流，由于在（U，V）平面的覆盖中存在有较大的空穴，所以“核”的两个分离部分内都在不同程度上出现了一些不真实部分。该次实验的结果为高动态范围的观测提供了一定的依据。

简介：The3^rdInternationalConferenceonContinentalEarthquakes,Mechanism,Prediction,EmergencyManagement&Insurance(the3^rdICCE)washeldonJuly9-14,2004inBeijing,China.TheICCEhasbeenheldeverydecadesinceitwaslaunchedovertwentyyearsago.ThefirstICCE,withthetitle""""InternationalSymposiumonContinentalSeismicityandEarthquakePrediction""""(ISCSEP),hadinternationalsponsorshipandwassupportedbye.g.,UNESCOandhostedbytheSeismologicalSocietyofChina(SSC)inBeijingin1982.In1992inresponsetotheinitiativesfromtheUN'sInternationalDecadeforNaturalDisasterReduction(IDNDR),

简介：Combinedmulti-bodydynamicswithstructuraldynamics,anewdiscreteelementwithflexibleconnector,whichisapplicablefor3-Dbeamstructures,isdevelopedinthispaper.Boththegeneralizedelasticcoefficientmatrixoftheflexibleconnectorandthemassmatrixofdiscreteelementmaybeoff-diag-onalinageneralcase.Thezero-lengthrigidelementisintroducedtosimulatethenodeatwhichmultipleel-ementsarejointedtogether.Itmayalsobeeffectivewhentheaxesofadjacentelementsarenotinthesameline.Theexamplesforeigenvaluecalculationshowthatthemodelissuccessful.Itcanbeextendedtothegeometricnonlinearresponseanalysis.

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简介：TheMM5anditsfourdimensionalvariationaldataassimilation(4D-Var)systemareusedinthispaper.BasedontheNationalCentersforEnvironmentalPrediction/NationalCenterforAtmosphericResearch(NCEP/NCAR)reanalysisdata,theauthorsgenerateanoptimalinitialconditionforatyphoonbyusingthebogusdataassimilation(BDA)scheme.BDAisabletorecovermanyofthestructuralfeaturesoftyphoonsincludingawarm-corevertex,thecorrectcenterposition,andthestrongcirculation.AsaresultofBDAusingabogussurfacelow,dramaticimprovementisachievedinthe72hpredictionoftyphoonHerb.Throughseveralcases,theinitializationbyBDAeffectivelygeneratestheharmoniousinnerstructureofthetyphoon,butwhichislackingintheoriginalanalysisfield.Thereforetheintensityforecastisimprovedgreatly.Someimprovementsaremadeinthetrackforecast,butmoreworkstillneedstobedone.

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简介：2003年4～6月,光温条件基本适宜,降水适中,对春播及夏收作物生长发育较为有利.

简介：Thetechniqueoncomputingthehorizontalpressuregradientforce(PGF)inRegCM2isimprovedwiththeerrorsubtractionmethod.Moreover,theregionalclimateinJuneof1991inChinaissimulatedbyemployingtheRegCM2.ComparisonwithotherschemesforcomputingthePGFshowsthattheerrorsubtractionmethodcaneffectivelyreducetheerrorofthePGF,improvethesimulationofwindsandalleviatethespuriousprecipitationinsteeptopographicareas.Furthermore,thesimulationofprecipitationinotherareasisinbetteraccordancewiththeobservation.

简介：TheNCARcommunityclimatemodelwasrunfor20yearsandthesimulatedEastAsianclimatewasanalyzedandcheckedagainsttheobservationdata.Itisfoundthatthelarge-scalefeaturesoftheEastAsiaclimateweresimulatedprettywellbythemodel,thoughtherearestillsomediscrepanciesbetweenthemodeloutputandtheobservation.Thesimulatedgeopotentialheight,windandtemperaturefieldsareveryclosetotheobservations.Thelargescalesystemssuchassubtropicalhigh.Mongoliahigh,IndianlowwhichhaveimportantinfluenceontheEastAsiamonsoonalsosimulatedprettywell.Itisalsofoundthatthemoisturefieldisnotsimulatedsowellasthosefieldsmentionedabove.Thesimulatedprecipitationisratherdifferentfromtheobservations.ThesesuggestthatsomephysicalprocessesintheCCM2needtobeimproved.

简介：泡沫能够通过减小流度和储层非均质性的影响提高采收率。数值研究表明，孔隙介质中的泡沫流动是由两种流动状态组成的。在“高值流动状态”中，压力梯度几乎与气体表观速度无关。

简介：从分析出现最低气温的时刻着手,提出了一个新的求取2时气温的公式。

简介：像注意到的那样，在实际孔隙介质中大部分液体占据了其自己的孔隙，毛细管压力控制着rc，并且Uw、rc、μs和△P之间的相互关系更复杂。该图说明了应用于更复杂的实际情况的原理：提高Uw将降低毛细管压力，这会降低气体粘度和减小△P。

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简介：Aseriesofidealizedmodelsimulationsareanalyzedtodeterminethesensitivityofmodelresultstodifferentconfigurationsofthelateralboundaryconditions(LBCs)insimulatingmesoscaleshallowconvectionoverhillyterrain.Inthesimulationswithsteadythermalforcingatthemodelsurface,aradiationconditionatbothboundariesisthebestchoiceunderhighwindconditions,andthebestresultsareproducedwhenboththenormalvelocitiesandthetemperaturearetreatedwiththeradiationschemeinwhichthephasespeedisthesamefordifferentvariables.Whenthebackgroundwindspeedisreasonablysmall,theLBCconfigurationwitheithertheradiationorthezerogradientconditionatbothboundariestendstomakethenumericalsolutionunstable.Thechoiceofaconstantconditionattheinflowboundaryandaradiationoutflowboundaryconditionisappropriateinmostcases.Inthesimulationswithdiurnalthermalforcingatthemodelsurface,differentLBCschemesarecombinedtogethertoreducespurioussignalsinducedbytheoutflowboundary.Aspecificationinflowboundarycondition,inwhichthevelocityfieldsattheinflowboundaryareprovidedusingthetime-dependentresultsofasimulationwithperiodicLBCsoveraflatdomain,istestedandtheresultsindicatethatthespecificationconditionattheinflowboundarymakesitpossibletouseasmallermodeldomaintoobtainreasonableresults.Themodelhorizontaldomainlengthshouldbegreaterthanacriticallength,whichdependsonthedomaindepthHandtheanglebetweengravitywavephaselinesandthevertical.Anestimateofminimumdomainlengthisgivenby[(H-zi)/πU]√N2L2x-4π2U2,whereNandUarethebackgroundstabilityandwindspeed,respectively,Lxisthetypicalgravitywavelengthscale,andziistheconvectiveboundarylayer(CBL)depth.

简介：ＰｒｏｃｅｓｓｏｆｓｏｕｒｃｅｄｙｎａｍｉｃｓｏｆｔｈｅＪｉｎｇｔａｉｅａｒｔｈｑｕａｋｅ（Ｍ＝６．２）Ｘｕｅ－ＢｉｎＤＵ（杜学彬）；Ｚｈｉ－ＤｅＹＡＮ（闫志德）ａｎｄＭｉｎｇ－ＷｕＺＯＵ（邹明武）（ＥａｒｔｈｑｕａｋｅＲｅｓｅａｒｃｈＩｎｓｔｉｔｕ...

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