简介:Astochastictwo-dimensionalFornasini-Marchesini'sModelⅡ(2-DFMMⅡ)withmultiplicativenoiseisgiven,andafilteringalgorithmforthismodel,whichisoptimalinthesenseoflinearminimum-variance,isdeveloped.Thestochastic2-DFMMⅡwithmultiplicativenoisecanbereducedtoa1-Dmodel,andtheproposedoptimalfilteringalgorithmforthestochastic2-DFMMⅡwithmultiplicativenoiseisobtainedbyusingthestateestimationtheoryof1-Dsystems.Anexampleisgiventoillustratethevalidityofthisalgorithm.
简介:Thispaperpresentsthedetaildesignconditions,designcriteriaandmethodsaswellasdesignconclusionsoftheprocess,structureandcorrosionoftheproductionflowlinesandhighpressurewaterinjectionlinesinBZ34-2/4oilfieldinBohaiBay.AtpresentthisdesignrepresentsthedesigncapabilityandlevelinthefieldofthesubmarinepipelineengineeringofChina.
简介:Shallowfreshwaterbodiesinpeatareascouldbeanimportantcontributortogreenhousegasesintheatmosphere.Inthisstudy,thepartialpressureofCO2inthesurfacewateroftheDianshanLakewasinvestigatedinsituinAugust2011.TheaveragepCO2inthestudyareawas2300μatmandfluctuatedwithintherangeof989–5000μatm.pCO2showedareversetrendtothevariationsofpHandDOinthesurfacewateroftheDianshanLake.ThewatertoairdiffusionfluxofCO2oftheupstream,middlelakeanddownstreamwererespectively63,33and14mmol/m2/d.Onaverage,thediffusionfluxofCO2ofthewholelakewas31mmol/m2/d.Consequently,ourresultsshowthatduringthesamplingseason,theDianshanLakeappearstobeagreatsourceofCO2.ItisalsodemonstratedthatrespirationcouldbethedominantbiochemicalreactionintheDianshanLakeinsummer.
简介:Naturalgascontaininghydrogensulphide(H2S)hasbeenfoundinseveralpetroliferousbasinsinChina,suchastheSichuanBasin,BohaiBayBasin,OrdosBasin,TarimBasin,etc.NaturalgaswithhigherH2Scontents(H2S>5%mol.)ismostlydistributedinboththegasreservoirsofDukouhe,Luojiazhai,PuguangandTieshanpo,whichbelongtotheTriassicFeixianguanFormationinthenortheasternSichuanBasinandthoseoftheKongdian-ShahejieformationsinthenortheasternJinxianSagoftheJizhongDepression,BohaiBayBasin.IntheSichuanBasin,theH2Scontentsofnaturalgasaverageover9%andsomecanbe17%,whilethoseoftheBohaiBayBasinrangefrom40%to92%,beingthenoneofthegasreservoirswiththehighestH2Scontentsintheworld.Basedondetailedobservationandsampleanalysisresultsofatotal5000mofcorefromover70wellsintheabove-mentionedtwobasins,especiallysulfurisotopicanalysisofgypsum,brimstone,pyriteandnaturalgas,alsowithintegratedstudyofthegeochemicalcharacteristicsofhydrocarbons,itisthoughtthatthenaturalgaswithhighH2Scontentsresultedfromthermochemicalsulfatereduction(TSR)reactions.Amongthem,thenaturalgasintheFeixianguanFormationresultedfromTSRreactionsparticipatedbyhydrocarbongas,whilethatintheZhaolanzhuangoftheJinxianSagbeingtheproductofTSRparticipatedbycrudeoil.DuringtheconsumptionprocessofhydrocarbonsduetoTSR,theheavyhydrocarbonswereapttoreactwithsulfate,whichaccordinglyresultedinthedrycoefficientofnaturalgasincreasingandthecarbonisotopesbecomingheavier.
简介:Inthisstudy,thecombinedactionsofwavesandtidalcurrentsinestuarineandcoastalareasareconsideredanda2Dmathematicalmodelforsedimenttransportbywavesandtidalcurrentshasbeenestablishedinorthogonalcurvilinearcoordinates.Non-equilibriumtransportequationsofsuspendedloadandbedloadareusedinthemodel.Theconceptofbackgroundconcentrationisintroduced,andtheformulaofsedimenttransportcapacityoftidalcurrentsfortheOujiangRiverestuaryisobtained.TheDouGuorenformulaisemployedforthesedimenttransportcapacityofwaves.SedimenttransportcapacityintheformofmudandtheintensityofbacksiltingarecalculatedbyuseofLuoZaosen'sformula.Thecalculatedtidalstagesareingoodagreementwiththefielddata,andthecalculatedvelocitiesandflowdirectionsof46verticallinesfor8crosssectionsarealsoingoodagreementwiththemeasureddata.Onsuchabasis,simulationsofbacksiltingafterexcavationofthewaterwaywithasandbarundercomplicatedboundaryconditionsinthenavigationchannelinducedbysuspendedload,bedloadandmudbywavesandtidalcurrentsarediscussed.
简介:ConflictingresultshavebeenpresentedregardingthelinkbetweenArcticsea-icelossandmidlatitudecooling,partic-ularlyoverEurasia.Thisstudyanalyzesuncoupled(atmosphere-only)andcoupled(ocean-atmosphere)simulationsbytheClimateForecastSystem,version2(CFSv2),toexaminethislinkageduringtheNorthernHemispherewinter,focusingonthesimulationoftheobservedsurfacecoolingtrendoverEurasiaduringthelastthreedecades.TheuncoupledsimulationsareAtmosphericModelIntercomparisonProject(AMIP)runsforcedwithmeanseasonalcyclesofseasurfacetemperature(SST)andseaice,usingcombinationsofSSTandseaicefromdifferenttimeperiodstoassesstherolethateachplaysindividually,andtoassesstheroleofatmosphericinternalvariability.Coupledrunsareusedtofurtherinvestigatetheroleofinternalvariabilitvviatheanalysisofinitializednredictionsandtheevolutionoftheforecastwithleadtime.
简介:为使用高度重新分配改进导出卫星的大气的运动向量(AMV)的质量的一个方法被介绍。位于高度重新分配下面的基本原理被探索,并且技术细节被使用使用NCEP分析风的三个高度重新分配计划学习。AMV的质量通常被改进跟随重新分配,尽管改进的大小根据使用的计划不同。计划3提供最好的质量和稳定性,在计划1和计划2列在后面。在AMV的带的部件的否定偏爱减少从[5,4]ms1到<1ms1追随者重新分配。南方的部件也改善。AMV源于红外线并且水蒸汽隧道分别地在58.7%和25%改善。使用在AMV的运作的推导的计划3的可行性被合并T511中等范围的数字天气预言(NWP)预言的预报风领域学习系统。合并12-h预报在从水蒸汽隧道检索的南方的风中在带的风和积极偏爱中减少否定偏爱,改进在26.7%的AMV的全面质量。线性地扩大预报领域的有效性时期在检索AMV减少改进,但是这减小的大小是小的。合并120-h预报地仍然导致13%改进,尽管它可以消除好质量的很多AMV。
简介:运用NCEP/NCAR1°×1°再分析资料、常规气象、加密自动站等资料对2010年6月17日和2005年5月31日2次冷涡造成的强对流天气进行了诊断分析,通过2次冷涡天气的三维结构特征分析表明:冷涡强对流天气落区均位于冷涡中心4~7个纬度的西南象限;当正涡度柱倾斜度越大越有利冰雹天气的产生;低层辐合,高层辐散,且垂直上升运动越强越有利冰雹天气的产生;冷涡东南象限500hPa、850hPa温度平流分布均为暖平流时,强对流天气则以降水为主,而冷涡东南象限500hPa为冷平流,850hPa为暖平流时,强对流天气则以大风、冰雹为主;低层强锋生区域与强对流天气区域有很好的对应关系,锋生函数正值中心区域北侧常出现大范围冰雹天气;2次过程的强对流天气生成都是由于地面气旋性辐合中心在温度发展中的锋区叠加中有明显的锋生而导致,地面气旋性辐合中心对雷暴的触发及发展提供了很好的动力抬升作用。
简介:依据《中华人民共和国测绘法》、《测绘资格审查认证管理规定》和《(测绘资格证书)持证单位年度检验办法》,我局对2003年度《测绘资格证书》年检中给予缓期登记的14家单位经过整改后提交的补充材料和未按时参加年检的10家单位提交的年检材料进行审查,其中通过2003年度《测绘资格证书》年检单位20家,
简介:以闽江河口感潮段塔礁洲野慈姑(SagittariatrifoliaL.)淡水湿地为研究对象,2015年12月—2016年10月每月小潮日定期向试验样地施加0、60和120kgS·hm-2·a-1的K2SO4溶液,探讨闽江河口感潮段淡水湿地CO_2排放通量特征对SO_4~(2-)沉降的响应,并同步观测主要环境因子。结果表明,1)对照(CK)和2个SO_4~(2-)沉降处理CO_2排放通量具有相似的月变化动态,夏秋季节排放通量较高,冬春较低。2)除夏季60kgS·hm-2·a-1的SO_4~(2-)输入显著降低CO_2排放通量外(P〈0.05),2种SO_4~(2-)处理均未显著影响河口感潮段淡水湿地CO_2排放通量(P〉0.05)。3)相关分析显示,不同处理下的CO_2排放通量与土壤温度显著正相关(P〈0.01)。
简介:为了核实赤峰1号井2014年初气汞异常现象,安装ATG-6138M测汞仪与原DFG-B测汞仪进行对比观测。ATG-6138M测汞仪观测到赤峰1号井房内空气汞浓度明显高于井孔内逸出汞浓度,表明观测井房可能存在汞污染问题。两台仪器同步观测井孔内逸出气汞浓度结果表明,ATG-6138M测汞仪测试结果稳定,动态清晰,而DFG-B测汞仪观测误差较大。对比DFG-B测汞仪与ATG-6138M测汞仪校准结果认为,DFG-B测汞仪已不能正常观测汞浓度的变化,存在捕汞管老化等仪器问题。综合分析表明,赤峰1号井DFG-B测汞仪存在环境汞污染和仪器老化等因素,且集气装置不符合地震行业标准技术要求,2014年初出现的气汞浓度异常信度不高,不能作为与地震孕育有关的前兆异常信息。