简介:Generally,thereliabilityofami-slidingandanti-overturningstabilityofanisolatedgravitycylinderinacertainworkingperiodcanbeevaluatedonlywhenthestatisticalpropertiesofshorttermstabilityaregivenfirst.Theauthorsusednumericalmethodtosimulatethestabilitystatefunctionofacylinderinshort-crestedsea,andfurthertogettheprobabiliticalcharacteristicsofthestructure’sstabilitybytimedomainanalysis.Theexternalloadsappearedinthestatefunctionsincludehorizontalwaveforce,liftforceandtherespectivemoments,andtheloadsarecorrelatedbyco-spectrum.Thenumericalmethodpresentedinthispapercanbeusednotonlytosolveshorttermreliabilityproblemdirectly,buttocalculateandanalysethelongtermreliabilityproblemaswell.Forcircularcylinders,anexampleofsimulationandanalysisisdisplayedinthispaper.
简介:摘要:S700K交流电动转辙机是我国高速铁路中常用的道岔转换设备,对维持列车运行安全和提高线路运输效率具有重要作用。因此,对于其在使用中出现的异常状态,进行及时的检测、识别、分类及处理,可以将提速道岔故障对列车运行造成的危害降到最低,有效减少维修的经济成本。本文针对S700K提速道岔常见的故障模式总结,根据道岔的故障现象得出其故障原因,对故障点进行判断并给出故障处理意见,为现场维护人员今后的工作提供一定的指导和帮助。
简介:采用哈巴河县观测站1961—2008年逐月平均气温、平均最高、平均最低气温资料.利用一元回归和R/S方法,分析了哈巴河县四季和年平均气温、年平均最高气温、年平均最低气温的变化特征。结果表明:近48年以来,哈巴河县冬、夏、秋季平均气温及全年平均气温序列均表现为升温的趋势,其中冬季升温最为明显:四季和年平均最高和最低气温近48年来也呈上升趋势.并且四季和年平均最低气温的上升趋势比四季和年平均最高气温的上升趋势显著。经R/S分析表明,未来四季中夏、秋、冬季及年平均气温仍呈上升趋势且持续时间较长,而春季气温上升趋势不明显;四季和年平均最高、最低气温未来上升的趋势也将继续存在,且最低气温的持续性比最高气温的持续性长,夏、秋两季最低气温升温趋势相对其他两季较为明显,而夏、冬两季的最高气温的升温趋势相对其他两季较为明显。总之.近48年来哈巴河县气温总体变化趋势存在明显的hurst现象.未来这种现象也仍将持续。
简介:BasedonthesimulationwiththeOcean-AtmosphereCoupledModelCCSMandOceanModelPOPunderthegreenhousegasemissionscenariooftheIPCCSRESA2(IPCC,2001),andontheearthcrustsubsidenceandglaciermeltingdata,therelativesealevelchangeisobtainedalongthecoastofChinainthe21stcentury.UsingtheSRTMelevationdatathesubmergenceofcoastallowlandiscalculatedundertheextremewaterlevelwitha100-yearreturnperiod.Thetotalfloodingareasare98.3×103and104.9×103km2for2050and2080,respectively.Forthethreeregionsmostvulnerabletoextremesealevelrise,i.e.,thecoastofBohaiBay,theYangtzeRiverDeltatogetherwithneighboringJiangsuProvinceandnorthernZhejiangProvince,andthePearlRiverDelta,thefloodedareasare5.0×103,64.1×103and15.3×103km2in2050and5.2×103,67.8×103and17.2×103km2in2080,respectively.
简介:<正>AfterstudyingsystematicallyPetrology,Mineralogy,Petrochemistry,REEgeochemistryandstrontium,sulphur,leadisotopeofthealkali-richgraniteprophyrydistribuledextensivelytheYangtzeplatfromwesternmargin’salkali-richgraniteporphyrywepointoutthatthealkali-richgraniteporphyryhavethepropertiesofnewintrusiveages,Rangeoftheisotopeageisform36Mato51Ma,theybelongtotheHimalayadate,Mainmineralcomponetsofthealkali-richgraniteporphyryconsistofk-fcldspar(35~45x),quartz(36x±)plagioclase(15x±)andbiotitc(10x±).Accessorymineralsoftherockbelongtotypeof
简介:在2014年11月下旬,当在国家博物馆在人的解决上出席科学展览时,李克锵总理关于胡焕勇线提出了一个问题到协会和科学家,媒介它随后称了首相问题。这增加了在胡焕勇线的了解和兴趣并且发射了挑起了许多看法的活泼的争论。在到首相询问的地址的一次尝试,这份报纸第一考察胡焕勇线的起源,依照著名人口地理学者命名在国内人中过剩上作为更宽的争论的部分在1935建议了它。用从瓷器的人口统计的数据第一,第五和第六普查,以及ArcGIS平台,我们在区域东南和胡焕勇线的西北分析人口的尺寸,比例和密度,证明都市化和移植没改变人口分发的模式由胡焕勇观察了。基于这,我们建议线和线的稀少的人口西北的稠密的人口东南的模式根本上不在一相对长的时间变化,城市的凝块的状况也主要不在东南的区域被发现。我们也主张气候和另外的物理地理条件决定胡焕勇线将留在地方。我们相信李克锵总理提出的问题是可解决的,并且与积极政策指导和合理空间组织,西北的区域能完成更多的现代化和更好优秀的都市化,当一样为中央区域是真的时。
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简介:塔里木盆地库车坳陷的S气井所在气藏表现为超高压低孔低渗砂岩凝析气藏特征,现场关井测试时间较短,导致未出现径向流或边界特征,采用常规试井解释方法进行不稳定试井资料的解释时呈现多解性。因此,针对该井历次测试中的压力恢复数据,对比分析“直井+有限导流+均质+矩形封闭边界”模型和“直井+有限导流+均质+平行封闭边界”模型常规试井解释的全程压力史拟合结果发现,选用“直井+有限导流+均质+矩形封闭边界”模型对历次压力恢复双对数特征曲线及压力历史拟合较好,与反褶积试井解释结果所表现出的全封闭边界特征吻合。结果表明,反褶积试井综合了多次压力恢复测试及生产数据,获取了比单次压力恢复常规试井更多、更全的边界信息,能更好地拟合整个生产历史,提高了试井解释结果的准确性和工作效率,对低渗透油气藏的不稳定试井解释具有指导意义。
简介:WhileattendanceatpreviousIGC'swasremarkable,themorethan7,000earthscientists,exhibitorsandguestswhometinFlorenceforthe32^ndInternationalGeologicalCongresssetanall-timerecordasthehighestnumberofparticipants.Theycamefrom120countriesand75%werenotItalian.Thisproportionofforeignattendeeswasthelargestever;inlinewithatrendofincreasingnonlocalparticipation,ittestifiestothevitalityandinternationalcharacteroftheIGCs.
简介:TheextensivedamagetobuildingscausedbytheNepalM_s8.1earthquakehasattractedmuchattentionbytheinternationalcommunity.AfterthepreliminaryscientificinvestigationsonthedifferentaffectedareasinNepal,theconstructionanddamagecharacteristicsoffivedifferenttypesofbuildingscommonlyexistinginNepalwerediscussedandthereasonsoftheirdisasterperformancewereanalyzed.Typesofbuildingsinvestigatedincludereinforcedconcrete(RC)framestructures,rubblestructures,brick-woodstructures,rawsoilstructures,andbrick-woodstructuresofhistoricbuildings.Inaddition,theweaklinksoftheseismicdesignwerepointedout,whichwasveryimportantforthepost-earthquakereconstructionandrecovery,andgaveapreliminaryexplanationsforthedamageexperienced.
简介:Theclassificationaccuracyofthevariouscategoriesontheclassifiedremotelysensedimagesareusuallyevaluatedbytwodifferentmeasuresofaccuracy,namely,producer'saccuracy(PA)anduser'saccuracy(UA).ThePAofacategoryindicatestowhatextentthereferencepixelsofthecategoryarecorrectlyclassified,whereastheUAofacategoryrepresentstowhatextenttheothercategoriesarelessmisclassifiedintothecategoryinquestion.Therefore,theUAofthevariouscategoriesdeterminesthereliabilityoftheirinterpretationontheclassifiedimageandismoreimportanttotheanalystthanthePA.ThepresentinvestigationhasbeenperformedinordertodetermineifthereoccursimprovementintheUAofthevariouscategoriesontheclassifiedimageoftheprincipalcomponentsoftheoriginalbandsandontheclassifiedimageofthestackedimageoftwodifferentyears.WeperformedtheanalysesusingtheIRSLISSIIIimagesoftwodifferentyears,i.e.,1996and2009,thatrepresentthedifferentmagnitudeofurbanizationandthestackedimageofthesetwoyearspertainingtoRanchiarea,Jharkhand,India,withaviewtoassessingtheimpactsofurbanizationontheUAofthedifferentcategories.TheresultsoftheinvestigationdemonstratedthatthereoccurssignificantimprovementintheUAoftheimperviouscategoriesintheclassifiedimageofthestackedimage,whichisattributabletotheaggregationofthespectralinformationfromtwicethenumberofbandsfromtwodifferentyears.Ontheotherhand,theclassifiedimageoftheprincipalcomponentsdidnotshowanyimprovementintheUAascomparedtotheoriginalimages.