简介：Adatastreamisamassiveunboundedsequenceofdataelementscontinuouslygeneratedatarapidrate.Duetothisreason,mostalgorithmsfordatastreamssacrificethecorrectnessoftheirresultsforfastprocessingtime.Theprocessingtimeisgreatlyinfluencedbytheamountofinformationthatshouldbemaintained.Thisissuebecomesmoreseriousinfindingfrequentitemsetsorfrequencycountingoveranonlinetransactionaldatastreamsincetherecanbealargenumberofitemsetstobemonitored.WehaveproposedamethodcalledtheestDecmethodforfindingfrequentitemsetsoveranonlinedatastream.Inordertoreducethenumberofmonitoreditemsetsinthismethod,monitoringthecountofanitemsetisdelayeduntilitssupportislargeenoughtobecomeafrequentitemsetinthenearfuture.Forthispurpose,thecountofanitemsetshouldbeestimated.Consequently,howtoestimatethecountofanitemsetisacriticalissueinminimizingmemoryusageaswellasprocessingtime.Inthispaper,theeffectsofvariouscountestimationmethodsforfindingfrequentitemsetsareanalyzedintermsofminingaccuracy,memoryusageandprocessingtime.

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简介：BasedontheFloquettheoryonordinarydifferentialequationswithperiodicallyvariablecoefficientsandthebifurcationapproachtononlinearequations,anumericalapproachtodeterminingthestabilityregionofcontrolparametersisestablishedforadynamiccontrolsystemcomposedofamovingbodylevitatedmagneticallyoverflexibleguideways.Thesystemisnonlinearlycoupledamongtheelasticdeformationofguideways,disturbancethelevitationpositionofthebodyandelectromagneticcontrolforces.Thenumericalsimulationisgivenforthesysteminthecaseinwhichthecontrolparametersaretakenwithinandoutofthestabilityregionrespectively.Resultsshowthatthisapproachisreliable.

简介：从在预言在在6月的华南(SC)的车站规模降雨被评估的亚太经济合作(APEC)气候中心(APCC)多模型整体(MME)的各种各样的动态模型的表演。模型hindcasts的MME平均数能熟练地预言在SC领域上平均的6月降雨异例，这被发现。这能与在在Indo和平的区域捕获在SC降雨和大气的大规模发行量异例之间的观察连接的MME能力有关。对基于直接模型输出(DMO)，超过97在SC驻扎的车站规模6月降雨预言的另外的评价表明MME平均数超过每个单个模型。然而，在某内陆的差的预言能力和东南的SC车站在MME平均数并且在很多个模型是明显的。以便与差的DMO预言技巧在那些车站改进表演，一个基于车站的统计downscaling计划被构造并且适用于个人和MME吝啬的hindcast跑。为几个模型，这个计划能在超过30个车站超过DMO，因为它能在捕获SC降雨更加敏感的异常Indo和平的对发行量拍进模型的能力。因此，提高了在这些模型的预言能力应该使他们成为的降雨为灾难有准备和缓解目的更有用。

简介：Consideringenergyshortage,largemoleculesincorncobandeasyseparationofsolidcatalysts,nanooxidesareusedtotransformcorncobintousefulchemicals.Becauseofthemicrocrystals,nanooxidesofferenoughaccessiblesitesforcellulose,hemicelluloseandmonosaccharidefromcorncobhydrolysisandoxidant.Chemicalconversionofcorncobtoorganicacidsisinvestigatedovernanoceria,alumina,titaniaandzirconiaundervariousatmospheres.Liquidproductsaremainlyformicandaceticacids.Asmallamountofothercompounds,suchasD-xylose,D-glucose,arabinoseandxylitolarealsodetectedsimultaneously.Theyieldoforganicacidsreaches25%–29%overthenanooxideofceria,zirconiaandaluminawith3hreactiontimeunder453Kand1.2MPaO2.Theuniqueandfastconversionofcorncobisdirectlyapproachedoverthenanooxides.Theresultsarecomparativetothoseofbiofermentationandofferanalternativemethodinchemicallycatalyticconversionofcorncobtousefulchemicalsinaone-potchemicalprocess.

简介：Theexhibitionco-sponsoredbytheChinaAssociationforPreservationandDevelopmentofTibetanCultureandtheGovernmentofGarzeTibetanAutonomousPrefectureinSichuanProvincewasheldfromJuly30thtoAugust30thintheBeijingEthnicCulturePalace.

简介：UsingtheNationalCenterforEnvironmentalPredictionreanalysisdataon1.0°×1.0°gridsanddatafromtheTropicalCycloneyearbook(2000),adiagnosticanalysisandnumericalsimulationwereperformedtoinvestigatethecharacteristicsandmechanismunderlyingtherapidweakeningoftyphoonXangsane.TheresultsshowthatasharpdeclineintheintensityoftyphoonXangsaneresultedfromitsmovementintothecoolseasurfacetemperatureareaintheEastChinaSea,theintrusionofcoldairfromthemainlandintothetyphoon,andarapidincreaseoftheverticalwindshearinthesurroundingenvironment.Animportantfactorthatledtothedemiseofthetyphoonwasasignificantdecreaseinthemoisturetransportintothetyphoon.Furthermore,theresultsofthenumericalsimulationandsensitivityexperimentsindicatethatseasurfacetemperaturelargelymodulatedtherapidweakeningoftyphoonXangsane.

简介：TropicalCyclone(TC)tracksoverthewesternNorthPacific(WNP)during1949–2007,obtainedfromChinaMeteorologicalAdministration/ShanghaiTyphooninstitute,areclassifiedintothreetracktypes.ThesetypesarethemainpathwaysbywhichTCsinfluencethecoastofEastAsia.Therelationshipsbetweenlocalseasurfacetemperature(SST)inWNPandTCtracksarerevealed.ResultsshowthatthelocalSSTplaysanimportantroleinTCtracks,thoughtherelationshipsbetweenlocalSSTandthefrequenciesofdifferentTCtracksareverydissimilar.ThelocalSSThassignificantpositivecorrelationwithnorthwest-pathTCs,andnegativecorrelationwithrecurving-pathTCs.However,thewest-pathTCsdonothavestatisticallysignificantrelationshipwiththelocalSST.TheupperseatemperatureanomalieswhichinfluenceTCtrackslastaboutsixmonthsbeforeTCoccurrence.FurtheranalysisindicatesthattheoceanconditionsinfluenceTCtracksbymodifyingtheatmosphericcirculation,andthenthemodifiedatmosphericcirculationcanaffectTC’sgenesislocationandmotion.

简介：Theworldwillcontinuetochangeradicallyoverthenextfivetotenyears.Thecurrent'onesuperpowerandmanypowers'orderwillchangetooneofmulti-polarity.Relationsbetweenmajorpowerswilltakeonanewshape.Therateofchangewillstarttoacceleratebutthesechangeswillcontinuetobepeacefulandincremental.Competitionwillintensifyoverwhowillsettherules.Chaos,disorder,uncertaintyandeventurmoilwillgrowmoreapparentintheinternationalsecuritysituation.Thiswillmakenationsseeknewsecuritystrategiesandmechanisms.

简介：变量领域象ens纪念品那样，南方风、带风的变量从月刊500hPa重力势高度异常场被导出。在这个工作，我们在1958的6月从每月的500-hPa重力势高度异常场和他们的变量选择原来的预言者-2001，并且由与原来的预言者分别地进行实验直角的功能(文件结束)决定全面预言者。一个downscaling预报模型基于背繁殖(BP)，神经网络被全面预言者的使用造与每月有活力的扩大范围预报产品在Guangxi上在6月预言每月的降水。为比较，我们也造神经网络与一样建模的另一BP由使用在5月从500-hPa重力势高度异常场选择到1957的12月的以前的全面预言者预言ands-2000并且1月到1958的4月-2001。二个模型被测试，结果证明downscaling模型的重叠的精确基于以前的全面预言者，而是downscaling模型的预言精确性比那的好取决于每月有活力的扩大范围预报的产量。

简介：[1]Ci,S.,Sharif,H.,2002.AVariableDataRateSchemetoEnhanceThroughputPerformanceofWirelessLANs.IEEECSNDSP.[2]Doufexi,A.,Armour,S.,Butler,M.,Nix,A.,Bull,D.,2001.AstudyoftheperformanceofHiperlan/2andIEEE802.11aphysicallayers.IEEEVTC,1:668-672.[doi:10.1109/VETECS.2001.944927][3]Doufexi,A.,Armour,S.,Karlsson,P.,Butler,M.,Nix,A.,Bull,D.,2002.AcomparisonoftheHiperlan/2andIEEE802.11aWirelessLANstandards.IEEECommunicationsMagazine,40(5):172-180.[doi:10.1109/35.1000232][4]Ferré,P.,Doufexi,A.,Chung-How,J.,Nix,A.,Bull,D.,2003.LinkAdaptationforVideoTransmissionoverCOFDMBasedWLANs.IEEESCVT.Eindhoven.[5]Girod,B.,Kalman,M.,Liang,Y.,Zhang,R.,2002.Advancesinchannel-adaptivevideostreaming.JournalofWirelessCommunicationsandMobileComputing,2(6):573-584.[doi:10.1002/wcm.87][6]Haratcherev,I.,Langendoen,K.,2004.HybridRateControlforIEEE802.11.ACMInternationalWorkshoponMobilityManagementandWirelessAccess(MobiWac),Philadelphia.[7]Haratcherev,I.,Langendoen,K.,Lagendijk,I.,Sips,H.,2002.D3.16:Application-directedAutomatic802.11RateControl.GigaMobileProject,TUDelf,Tech.Rep.[8]Haratcherev,I.,Langendoen,K.,Lagendijk,R.,Sips,H.,2004.SNR-basedRateControlinWaveLAN.ASCI2004Conference.PortZelande.[9]Haratcherev,I.,Taal,J.,Langendoen,K.,Lagendijk,R.,Sips,H.,2005.AutomaticIEEE802.11ratecontrolforstreamingapplications.WirelessCommunicationsandMobileComputing,5(4):421-437.[doi:10.1002/wcm.301][10]Hoffman,C.,Manshaie,M.H.,Turletti,T.,2005.CLARA:Closed-LoopAdaptiveRateAllocationforIEEE802.11WirelessLANs.IEEEWirelessCom'.Hawaii.[11]Holland,G.,Vaidya,N.,Bahl,P.,2001.ARate-AdaptiveMACProtocolforMulti-HopWirelessNetworks.Mobicom.Rome.[12]H264software,2005.H.264/AVCSoftwareCoordination.http://bs.hhi.de/～suehring/tml/.[13]IEEE802.11,1999.Part11:WirelessLANMediumAccessControl(MAC)andPhysicalLayer(PHY)Specifications.[14]IEEE802.11a,1999.Part11:WirelessLANMediumAccessControl(MAC)andPhysicalLayer(PHY)Specific

简介：Itisimportanttoquantitativelyunderstandthemethaneadsorptionandtransportmechanismincoalforanevaluationofthereservesandforitsproductionforecast.Inthiswork,ablockcoalsamplewaschosentoperformtheCH4adsorptionexperimentsusingthegravimetricmethodattemperaturesof293.60K,311.26K,332.98Kand352.55Kandpressuresupto19MPa.TheexcessadsorptioncapacityofCH4indryblockanthraciteincreased,followedbyasequencedecreasewiththeincreasingpressure.Hightemperaturerestrainedthegrowthoftheexcessadsorptionduetothattheadsorptionisanintrinsicallyphysicalandexothermicprocess.Theexcessadsorptionpeakdecreasedslowlywiththeincreaseoftemperatureandintersectedatapressureofmorethan18MPa;meanwhile,thepressureattheexcessadsorptionpeakincreased.Theexistingcorrelationswereexaminedintermsofdensityratherthanpressure.TheDR+kcorrelation,withanaveragerelativedeviationof±0.51%,fittedourdatabetterthantheothers,withanaveragerelativedeviationofupto2.29%.ThetransportationcharacteristicsofCH4adsorptionwasalsoinvestigatedinthisstudy,includingtheadsorptionrateanddiffusioninblockcoal.Thekineticdatacouldbedescribedbyamodifieduniporemodel.Theadsorptionrateswerefoundtoexhibitdependenceonpressureandtemperatureatlowpressures,whilethecalculateddiffusivitiesexhibitedlittletemperaturedependence.Inaddition,thekineticcharacteristicswerecomparedbetweenCH4andCO2adsorptionontheblockcoal.TheexcessadsorptionratiosofCO2toCH4obtainedfromtheDR+kmodeldecreasedwiththeincreasingpressure.

简介：AccordingtotheshipobservationdataovertheSouthIndianOceanduring1950--1995,taking1°×1°and5°×5°grid,thecharacteristicsandvariationruleofwindareanalyzed.Throughanalyzingthechartofisoplethsofthemonthlyelements,theconclusionthattheseasonalvariationofthewindfieldovertheSouthIndianOceanislessremarkablethanthatintheoceansoftheNorthernHemisphereisgot.Theseasonalvariationofthewindfieldisalsoobviousinthisregion,buttheseasonaldifferenceislittle.Thewindinwinterisstrongerthaninsummer,correspondingly,theaveragewindspeedishigher,andthefrequenciesofgaleofforces≥6and8arealsohigher.Thenorthof10°Sisamonsoonarea;Southeastwindprevailsallovertheyearintherestofthetradewindarea;Westerlywinddominatesinthesouthof40°S.Thispaperprovidesspecificdataofwindfieldandvariationforshipoceantransportation,ocean-goingvisitsandscientificexperiment.

简介：ByusingtheBetts-Miller-Janji’c,Grell-Devenyi,andKain-FritschcumulusconvectiveparameterizationschemesintheWeatherResearchandForecasting(WRF)model,longtimesimulationsfrom2000to2009areconductedtoinvestigatetheimpactsofdifferentcumulusconvectiveparameterizationschemesonsummermonsoonprecipitationsimulationoverChina.Theresultsshowthatalltheschemeshavethecapabilitytoreasonablyreproducethespatialandtemporaldistributionsofsummermonsoonprecipitationandthecorrespondingbackgroundcirculation.Theobservednorth-southshiftofmonsoonrainbeltisalsowellsimulatedbythethreeschemes.DetailedcomparisonindicatesthattheGrell-Devenyischemegivesabetterperformancethantheothers.Deficiencyinsimulatedwatervaportransportisonepossiblereasonfortheprecipitationsimulationbias.

简介：Laminarheattransferproblemisanalyzedforadiskrotatingwiththeangularspeedωinaco-rotatingfluid(withtheangularspeedΩ).Thefluidisswirledinaccordancewithaforced-vortexlaw,itrotatesasasolidbodyatβ=Ω/ω=const.Radialvariationofthedisk’ssurfacetemperaturefollowsapowerlaw.Anexactnumericalsolutionoftheproblemisobtainedbasingontheself-similarprofilesofthelocaltemperatureoffluid,itsstaticpressureandvelocitycomponents.NumericalcomputationsweredoneatthePrandtlnumbersPr=1(?)0.71.Itisshownthatwithincreasingβbothradialandtangentialcomponentsofshearstressesdecrease,andtozerovalueatβ=1.Nusseltnumberispracticallyconstantatβ=0(?)0.3(andevenhasapointofamaximuminthisregion);Nudecreasenoticeablyforlargerβvalues.

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简介：ThenumericalsolutionofincompressibleviscousflowoveranaerofoilisobtainedbyH-typegridsandaspecialdifferencescheme.Themethodofmassfluxcorectionisintroducedwithsuccessinordertoaccelerateconvergenceiniterationofvelocityandpressurecalculation.

简介：这篇文章考虑由与利用一个单个一半双的继电器的相应目的地交流的多重来源组成的一个无线网络，而，来源机会主义地使用继电器。由与有效电容的概念集成信息理论，这篇文章在瞄准最大化继电器网络产量的无线继电器网络上建议动态时间分配策略，题目到服务(QoS)的给定的延期质量限制，在哪儿预定分割多重存取(TDMA)在继电器网络被使用。模拟结果证明建议分配策略罐头显著地作为与传统的相等的时间分配策略相比改进有效能力。

简介：Cloudmicrophysicalpropertyretrievalsfromtheactivemicrowaveinstrumentonasatelliterequiretheclouddropletsizedistributionobtainedfromaircraftobservationsasaprioridataintheiterationprocedure.Thecloudlognormalsizedistributionsderivedfrom12flightsoverBeijing,China,in2008–09werecharacterizedtoevaluateandimproveregionalCloudSatcloudwatercontentretrievals.Wepresentthedistributionparametersofstratiformclouddroplet(diameter<500μmand<1500μm)anddiscusstheeffectoflargeparticlesondistributionparameterfitting.Basedonthreeretrievalschemeswithdifferentlognormalsizedistributionparameters,theverticaldistributionofcloudliquidandicewatercontentwerederivedandthencomparedwiththeaircraftobservations.Theresultsshowedthattheliquidwatercontent(LWC)retrievalsfromlargeparticlesizedistributionsweremoreconsistentwiththeverticaldistributionofcloudwatercontentprofilesderivedfrominsitudataon25September2006.WethenappliedtwoschemeswithdifferentaprioridataderivedfromflightdatatoCloudSatoverpassesinnorthernChinaduringApril–Octoberin2008and2009.TheCloudSatcloudwaterpath(CWP)retrievalswerecomparedwithModerateResolutionImagingSpectroradiometer(MODIS)liquidwaterpath(LWP)data.TheresultsindicatedthatconsideringaprioridataincludinglargeparticlesizeinformationcansignificantlyimprovetheconsistencybetweentheCloudSatCWPandMODISCWP.Theseresultsstronglysuggestthatitisnecessarytoconsiderparticleswithdiametersgreaterthan50μminCloudSatLWCretrievals.

简介：在这篇论文我们在场为在多使用十的一间套房建模的中国和我们的超级整体上的降水的数字天气预言的当前的能力基于预报。我们模型的套房包括NCARTIGGE档案为THORPEX程序选择的运作的套房。这些是：ECMWF，UKMO，JMA，NCEP，CMA，CMC，BOM，MF，KMA和CPTEC当模特儿。超级整体策略包括训练和一个预报阶段，为这些为这研究选择的时期通过9月包括月2月年2007和2008。地址降水为中等范围预报的这篇论文即天1～3并且用全球模型的这间套房伸出到白天10预报。为训练和我们使用了的预报确认，一颗先进TRMM卫星基于降雨产品。我们为包括RMS错误，空间关联和公平威胁分数的预报确认使用标准度量标准。降水的技巧预报的结果清楚地证明为降水预报获得更高的技巧天是可能的1通过从使用的3张预报多作为与这间套房的最好的模型相比为超级整体建模。在天之间4～10有很高的技巧从是可能的多为降水的RMS错误为超级整体建模。那些技巧为一条全球带并且特别在中国上被显示出。现象学地，这个产品也乍见陆地为华南海季风，mei-yu雨的生命周期和柱子台风的发作为降水预报被发现很有用大雨和洪水事件。更高的技巧多为超级整体建模为如此的实时事件使它成为一个很有用的产品。