学科分类
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295 个结果
  • 简介:<正>所谓3S技术即GPS、GIS、RS技术。GPS(全球定位系统)是英文缩写词NAVSTAR/GPS(NAVigationSystemTimeAndRanging/GlobalPositioningSystem)的简称。全称应为“测时测距导航系统/全球定位系统”。GPS是由美国研制,并投入实际应用的最新卫星定位系统。其主要目的是为飞机和船舶导航定位。也可以用于其它多种目的。GPS技术已在航空、航天、航海、军事、地质、石油、勘探、交通、测绘等领域得到广泛的应用。美国于1993年6月26日已将GPS21颗卫星和3颗备用卫星全部发射入轨。

  • 标签: “3S”技术 全球定位系统 数据库管理系统 3S技术 地理信息系统 导航系统
  • 简介:OnJune2011,theBeijingResearchInstituteofUraniumGeology,anInstitutewithintheChinaNationalNuclearCorporation(CNNC),andtheDepartmentofGeology&MiningCNNCcarriedoutaprojectScientificDrillingforDeepMetallogenicResearchintheXiangshanLargeUraniumOreField.AyearlateronJune21,theproject,representingthefirstscientificdrillingofChina’suranium,wasofficiallylaunched,andsuccessfullycompletedonJune17,2013.A2818.88mofdrillingdepthhasbrokenthepreviousrecord1200mofexplorationdepth.TheXD-35DBdrillingmachinedevelopedbyChinaGeo-EquipmentCorporationistheChina’sfirstAC-VFDDirectDriveTopDriveCoreDrill.Ithasgreatlyimproved

  • 标签: 中国核工业集团公司 勘探深度 铀矿田 世界 采矿 技术
  • 简介:塑造耳朵的热前面(ESTF),由黄海温暖的水流(YSWC)和山东沿海的水流(SCC)的集中形成了,在冬季是在黄海(YS)的很重要的海洋的现象。在所有表明的situ大小和分析数据集,ESTF在1950s-1990s,和一个类似的变弱趋势期间一直在变弱,这是也在YS上在冬季季风发现。数字实验证明变弱冬季季风能沿着瓷器海岸和向南方的异常水流与向北方异常的水流在多十的timescale上在YS导致异常发行量在里面中央对季节的吝啬的循环YSgenerally相反。异常发行量引起YSWC和SCC的减速,并且因此削弱ESTF。因为ESTF在地区性的海洋动力学和由空至海的相互作用起重要作用,它变弱在冬季在YS为地区性的气候有重要含意。

  • 标签: 热前面 黄海 循环 季风 多十的可变性
  • 简介:  Introduction  Withrapiddevelopmentandadvancementofeconomyandsociety,lotsofcitygroupsorcitybeltswithex-tra-largecitiesastheircentershavebeenformedinChina.Theregionsthesecitygroupslieinusuallyhavewell-developedeconomy,densepopulation,andareregionalpoliticsandculturecenters.Somegroupslieintheregionswithhighlevelofearthquakeactivity,suchastheSurroundingCapitalCityGroupwiththecentersofBei-jingandTianjin.Oncealargeearthquakeoccurs,itsinfluencewillspreadtoveryextensiveregionanditsdisasterwillbetremendoustoo.Soearthquakeresistanceanddisastermitigationofcitygroupwillbeverysignificantissue.Thecitiesinagrouphaveclosedistancewitheachother;theycancarryoutunifiedpreparationfordisasterasonewholeandreducetheheavyloadofsinglecitybeforeanearthquake,andhaveanadvantageofpromptmutual-aidafteranearthquakebecauseofclosedistance.Itisespeciallysignificanttomitigatetheloseoflives.Oneimportantpreconditionisthatallthecitiesinonegroupcannotbeexposedtothesamelevelofdestroyduringoneearth-quake.Sothedivisionofcitygroupintheregionwithdensecitiesdistributionshallbeverysignificanttotheemergentmutual-aidinearlytimeafteralargeearthquake.Forthisgoal,thecharacteristicsandcorrelativityofearthquake′simpactoncitiesinonegroupneedtoclearlybeconsidered.Thecitieswithsimilarfeaturesandstrongcorrelativityofhistoricalearthquakeinfluencehavelargechancetosuffersameleveldestroyduringthefuturestrongearthquakeandaredisadvantagetoprovidemutual-aidandshallnotbedividedintoonegroup.  ……

  • 标签: city group EARTHQUAKE IMPACT AFFECTED intensity
  • 简介:TheemergenceofZhangHeng’sseismoscopehasaprofoundhistoricalbackground.ThispaperintendstoexploretheformationandmaterialbasisofZhangHeng’sscientificthought.Itappearsthatthesimpleintentionof"observingvisionsanddistinguishinggoodfortuneormisfortune"washismotivationtodeveloptheseismoscope.Tracingitshistoricalbackground,theauthorsproposedinthispaperthatthedevelopmentofthisseismoscopestartedaround128A.D.,andbasedonperceptualknowledge,twoideasaboutearthquakescameintobeing,i.e.,earthquakelocationcouldbejudgedaccordingtotheinstrumentshakingdirection,andtheearthquakeandearthsplitwereessentiallydifferent.Intheinstrumentmanufacture,ZhangHengadvocatedaprincipleof"makingutensilstoimitatecosmos".Bythisprinciple,thefollowingthreeproblemswerereadilysolved:theseismoscopeimitatedtheresponseofthesuspensionsystemtoearthquakes(i.e.naturalseismoscope).Technically,thetriggermechanismofthelatchwasusedforreference,anditrecordedthephysicalevidenceofearthquakeoccurrencebyaningeniouswayofaballdroppingfromadragon’smouth.Thesolutionofthesethreekeyproblemsleadtotheemergenceoftheseismoscopein132A.D.andthesuccessfuldetectionofanearthquakein134A.D.Hisinventiondeepenedhumanity’sknowledgeofnaturallaws,andpromotedthedevelopmentofscienceandtechnologyinthattimeandlater.

  • 标签: 候风地动仪 张衡 地震定位 科学思想 仪器制造 物质基础
  • 简介:Long-termintegrationsareconductedusingtheSpectralAtmosphericModel(referredtoasSAMIL),whichwasdevelopedintheLaboratoryforNumericalModelingforAtmosphericSciencesandGeophysicalFluidDynamics(LASG)intheInstituteofAtmosphericPhysics(IAP),withdifferentresolutionstoinves-tigatesensitivityoftheMadden-JulianOscillation(MJO)simulationstothemodel'sresolution(horizontalandvertical).Threeresolutionsofthemodel,R15L9,R42L9andR42L26,withidenticalphysicalprocesses,allproducedthebasicobservedfeaturesoftheMJO,includingthespatiotemporalspace-timespectraandeastwardpropagation.Nofundamentaldifferencesamongthesesimulationswerefound.ThisindicatesthatthemodelresolutionisnotadeterminingfactorforsimulatingtheMJO.Detaileddifferencesamongthesemodelingresultssuggest,however,thatmodelresolutioncansubstantiallyaffectthesimulatedMJOincertainaspects.Forinstance,atalowerhorizontalresolution,highfrequencydisturbanceswereweakerandthestructuresofthesimulatedMJOwerebetterdefinedtoacertainextent.AhigherverticalresolutionledtoamorerealisticspatiotemporalspectrumandspatialdistributionofMJOprecipitation.Meanwhile,increasingthemodel'sresolutionimprovedsimulationoftheclimatology.However,increasingtheresolutionshouldbebasedonimprovingthecumulusparameterizationscheme.

  • 标签: 大气环流 大气季节内振荡 大气科学 大气流体力学模拟
  • 简介:In2004,China’sdigitalseismicobservationnetworkprojectbegantodeploy40setsYRY-4four-componentboreholestrainmetersinordertomonitorearthquakepreparationprocess.Thepaperdescribesobservedsolidtidalstraindiscretenessandtidalfactoranisotropy,analyzesthereliabilityofobservationaldataanddiscussesthecauseforthisphenomenon.Aftergettingridofinterferences,thenetwork,intwoyearspractice,hasobservedseveralpre-seismicstrainanomaliesatstationsclosetoepicentersespeciallyintheWenchuanMS8.0megaquake.Itshowsthatthisboreholestrainmeternetworkiscapableofmonitoringseismogenicprocess.

  • 标签: 应变网络 分量式 孔容 中国 地震孕育过程 观测网络
  • 简介:河的健康生活是对他们的生活条件的描述,并且它也与人的社会是对河的功能和关系的一个全面评价。Throughanalyzing人和河生态系统,连续流动,为水的安全的河隧道和沉积交通,好水质,持续的河生态系统和给水能力的要求被认为是健康黄河的符号。最小量,最大的洪水排出能力,满满的分泌物,泛滥平原的横向的斜坡,水质度,沼泽地区域,水的生态系统,和给水能力,总共八量的指示物被放作为健康黄河的符号,并且他们的相应标准redetermined基于有历史的水文学数据和1956-2004的观察数据的分析。

  • 标签: 黄河 指标体系 径流 水质
  • 简介:ThestudiesonthestructureandphysicalpropertiesoftheEarth'sinteriordonebyChinesegeophysicistsfrom1999to2002werereviewedinthispaper.Itincludesseveralresearchareas:thestructureoftheEarth'sinteriorsusingseismictomography,anisotropyoftheuppermantleinChinaanditsadjacentareas,qualityfactorQβforSwaves,subductionzone,mantlediscontinuities,physicalpropertiesofEarth'smaterialsandothers.Thereviewconcernsmainlythecontents,themethodsandtheresultsofthestudies.ItcanbeseenthatnewprogressinthestudyonthestructureandphysicalpropertiesoftheEarth'sinteriorhasbeenmadeinthelast4yearsinChina.Itisshownonthreeaspects:advancementmadeonsomepreexistentareas;pioneeringonsomenewfieldsandnewmethodsadopted.

  • 标签: 地球内部构造 物理性质 地震学 各向异性 断层
  • 简介:地理要素的分类编码是人类认知地理信息世界的成果,也是人类对地理信息世界再认知的人口和关键.在海洋地理信息领域,S-101数据标准即将替代现行S-57ENC标准,分类编码方案也将会相应改变.先对S-57到S-101的属性变化内容进行整体描述,再从地理要素属性、元要素属性、图示表达属性三方面内容,对新旧两套分类编码中的属性内容进行对比分析,为涉海人员消化吸收新标准提供一定的参考.

  • 标签: 海洋测绘 地理信息标准 电子海图 S-101 S-57 数据融合
  • 简介:Inordertotheoreticallystudythebucklepropagationofsubseapipelineswithslip-onbucklearrestors,atwo-dimensionalringmodelwassetuptorepresentthepipelineandanonlinearspringmodelwasadoptedtosimulatethecontactbetweenpipeline’sinnerwallsandbetweenpipeline’souterwallandslip-onbucklearrestor’sinnerwallduringbucklepropagation.Inaddition,somereversespringsareaddedtopreventthewallofleftandrightsidesseparatingfromtheinnerwallofslip-onbucklearrestors.Consideringlargedeformationkinematicsrelationsandtheelastic-plasticconstitutiverelationofmaterial,balanceequationswereestablishedwiththeprincipleofvirtualwork.Thevariationofexternalpressurewithrespecttothecross-sectionalareaofpipelineswasanalyzed,andthelowerboundofthecrossoverpressureofslip-onbucklearrestorswascalculatedbasedonMaxwell’senergybalancemethod.Bycomparingthetheoreticalresultswithexperimentandfiniteelementnumericalsimulation,thetheoreticalmethodisprovedtobecorrectandreliable.

  • 标签: subsea pipeline BUCKLE propagation NONLINEAR CONTACT
  • 简介:一座大楼城市的流动上的密度的效果与RNGκ用一个CFD模型被调查-ɛ骚乱闭合计划。有不同的造的27个案例是密度参数(例如,大楼和街峡谷纵横比)数字地被模仿。当大楼的密度参数变化,不同流动政体出现。当街峡谷相对狭窄、高时,在垂直方向的二个相反旋转的旋涡被产生。沿着街的风速被大楼的长度主要影响。然而,以一座单个大楼的密度参数发现或概括街峡谷流动的特征是很困难的。这是因为复杂流动模式由于旋涡结构和旋涡数字的变化出现。平均卷的涡度大小是很好的指示物尽管有流动的强壮的相关性,在大楼的密度参数的变化上反映流动特征。平均卷的涡度大小是大楼的长度和街峡谷宽度的强壮的功能的多线性的回归表演。大楼的长度的增加减少街峡谷的涡度流动,当时,在街上,峡谷宽度增加的增加涡度。

  • 标签: 城市气候学 影响 行人穿越车流 特征性 交通流 多维直方图算法
  • 简介:TheanalysesoflighthydrocarbonsinoilsfromtheTarimBasinshowthattheMango'sparameterKisaboutunityexceptthoseoilstrappedintheeasternpartoftheTazhong(CentralTarim)FaultUplift,TheregularvarianceofKmayindicatestheaccumulationandadmixtureoftheoilpopulationsintheeasternpartoftheTazhongFaultUplift.

  • 标签: 塔里木盆地 异庚烷 K参数 碳氢化合物 分布规律 油气运移
  • 简介:2004台风Aere的降水的结构的特征从测量国家航空学空间管理(NASA)的使命(TRMM)的热带降雨用高分辨率的数据被分析。台风的特征在它的发展的不同阶段变化,这被发现。分析降水分发的不对称的引起,从环境预言(NCEP)分析的国家中心的数据被用来计算水蒸汽流动向量的垂直积分。因为这个过程,结果显示出那,与成双台风的循环的唯一的现象一起,在东方台风的北方面的空气电流和它的南部的方面的西南的空气水流在搬运水起一个联合作用蒸汽。而且,它的运输效果在开发的不同阶段极大地变化,显示出为这台风进程的水来源的怪癖。由重降水和水蒸汽流动的一个最大值的区域描绘区域的台风传送对流的分布,以及在台风的发展的不同阶段的强壮的上升运动区域不同。水蒸汽流动和垂直运动的不一致的分发引起台风降水的不均匀的分发。

  • 标签: 台风降水 TRMM 蒸汽流动向量 不均匀的结构
  • 简介:First,Wirsching'smodel,whichiswidelyemployedinfatiguereliabilityanlysisofmarineandoffshorestructures,isanalysedsystematically.Itisfoundthattheveryimportantrandomvariable△inWirsching'smodelcannotbedirectlydeterminedfromfatigueexperimentbecauseoftheirreversibilityoffatiguetest,andinfact,whatWirschingstudiedfromtestingresultsisnot△butαofthestatisticalMiner'srule.Second,byuseofthestatisticalMiner'srule,amodifiedWirsching'smodelisproposed.Thirdlyandmoreimportantly,basedonthetwo-dimensionalprobabilisticMiner'srule,anewmodelisestablishedforfatiguereliabilityanalysisofstructuralcomponentssubjectedtospecifiedcyclicloadingofvariableamplitudeorstochastictimehistory.Intheend,anexampleispresented,fromwhichitwillbeseenthatthisnewmodelisveryconvenienttouseandfeasibletoengineeringpractice.

  • 标签: variable AMPLITUDE STOCHASTIC loading time history
  • 简介:TheimpactsofclimatechangeonChina'sagriculturearemeasuredbasedonRicardianmodel.Byusingcounty-levelcross-sectionaldataonagriculturalnetrevenue,climate,andothereconomicandgeographicaldatafor1275agriculture-dominatedcountiesintheperiodof1985-1991,wefindthatbothhighertemperatureandmoreprecipitationwillhaveoverallpositiveimpactonChina'sagriculture.However,theimpactsvaryseasonallyandregionally.Highertemperatureinallseasonsexceptspringincreasesagriculturalnetrevenuewhilemoreprecipitationisbeneficialinwinterbutisharmfulinsummer.Applyingthemodeltofiveclimatescenariosinthe2020sand2050sshowsthattheNorth,theNortheast,theNorthwest,andtheQinghai-TibetPlateauwouldalwaysbenefitfromclimatechangewhiletheSouthandtheSouthwestmaybenegativelyaffected.FortheEastandtheCentralChina,mostscenariosshowthattheymaybenefitfromclimatechange.Inconclusion,climatechangewouldbebeneficialtothewholeChina.

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