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  • 简介:Comprehensivestatisticalanalysiswasperformedonthebasicfeaturesoffocalmechanismsof619ML≥2.0earthquakeswhichoccurredinthecapitalcircleareafromJanuary2002toJune2010.Bydividingthecapitalareaintothreestudyingregionsbasedonregionaltectoniccharacteristics,clusteranalysiswasconductedonthefocalmechanismsofallsubregionsusingthelongestdistancemethodinthestatisticalclusteranalysistostudythecharacteristicsoftectonicstresstensors.TheresultshowsthatdominantP-axisazimuthdistributionisNNE-NEEandthatofT-axisisNNW-NWW,mostofthefocalareasarecontrolledbyahorizontalstressfieldandruptureismainlyofhorizontalstrike-slip.ThemaximumprincipalcompressionstressorientationisNE75°inthewest,NE62°inthemiddle,andnearEWintheeastofthecapitalarea.Theregionaltectonicstressfieldischaracterizedbyhorizontalcompression.

  • 标签: 首都圈地区 震源机制解 区域构造特征 区域构造应力场 中国 统计分析
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  • 简介:土地信息系统的不停的变化问题能通过重新分解和设计模式被解决。为了在开发再使用软件的土地信息系统支持设计模式和重新分解的方法的实现,设计,适用重新分解在土地信息系统开发的模式被讨论的到抽象工厂和装饰者设计的方法。

  • 标签: 土地信息系统 系统开发 重构 设计模式 GIS
  • 简介:AbstractBackground:Urbanization in China is rapidly proceeding, but rural-to-urban migration and its association with overweight and obesity is not well studied. This study aimed to explore the age at arrival, duration of migration, and the corresponding association with overweight/obesity in Yi migrants in China.Methods:A cross-sectional study was conducted in rural and urban areas in 2015 in Sichuan province, China. Demographic characteristics, lifestyle factors, and anthropometry were collected. General linear regression models were used to assess the effect of duration of migration (1-10, 11-20, 21-30, and >30 years) on body mass index (BMI). Multi-variable logistic regression was used to examine the association between duration of migration and overweight/obesity (BMI ≥ 25 kg/m2).Results:A total of 3056 Yi people (1894 Yi farmers and 1162 Yi migrants) aged 20 to 80 years were enrolled. After adjusting for age, sex, and other potential confounders, Yi migrants had 1.71 kg/m2 (95% confidence interval [CI]: 1.36-2.06) higher BMI and a 2.13-fold (95% CI: 1.71-2.65) higher risk of overweight/obesity than Yi farmers. In Yi migrants, stratified by age at arrival, no significant association between duration of migration and overweight/obesity was observed in those who were 0 to 20 years old at arrival. In comparison, in migrants >20 years old at arrival, compared with the reference group (1-10 years), long-term migration (>30 years) was found to be associated with overweight/obesity after adjustment (odds ratio: 1.85, 95% CI: 1.04-3.29).Conclusions:Yi migrants were observed to have greater risk of overweight/obesity than Yi farmers. In Yi migrants, the risk of overweight/obesity increased according to the duration of migration, especially in those who were older upon their arrival.

  • 标签: Migration epidemiology Overweight/obesity Rural-to-urban Yi people
  • 简介:TheelectricpowerindustryisafundamentalindustryinthenationaleconomyandtheChineseGovernmenthasalwaysputthepowerindustryonanimportantpriorityfordevelopment.Atpresent,keepingcontinuousrapidandstabledevelopmentofthepowerindustryfacestwochallengingissues—shortageofprimaryenergyresourcesandseriousenvironmentalpollution.Sothecleancoaltechnology(CCThereinafter)hasbeenplacedasoneofthemostpriorrealmfordevelopmentonthe

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  • 简介:Weldingtechnologyinoil-fieldconstructioninChina¥HOUXianzhong(DaqingOilField)Abstract:Thispaperintroducestheapplicationanddeve...

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  • 简介:Inlinewiththerapidlyexpandingelectricpowerindustryinthiscountry,Chinanowownsaworkforcetotalingmorethanhalfamillionofstaffandworkersengagedintheconstructionofthermalpowerprojects;alsothetechnologyemployedintheirworkhasexperiencednotableprogress.Intheearlyfifties,constructionworkmainlyreliedonmanualmanipulation.Besidestheuseofhand-orelectric-drivenover-headcranesinsidethemachine-house,verticaltransporta-tiondependedmainlyonhoistersandpulleys;chainblockswerescarceatthattime.Horizontaltransportationwasmainlydonebymanualpulley-blocksandrollers,sometimesalsowithwinches.Electric-orgas-weldingbyhandwasthecommonprac-tice.Inaword,thetechnologywasbackwardandlabor-inten-

  • 标签: morethan EXPANDING engaged TOWER BACKWARD SOMETIMES
  • 简介:Energyandenvironmentalissueshavebecomeincreasinglyprominentinmattersoftransportation.Comparedwithroad,air,andseatransportation,railwaytransportationhastheadvantagesofalargetransmissioncapacity,withrapid,safe,andon-timetravel,requiringlesslandresources,withlowerenergyconsumption,lessenvironmentalpollution,andthecapacitytooperateundermostweatherconditions.Inparticular,high-speedrailwaytechnologyhasbeengrowingrapidly.Sincetheworld'sfirsthigh-speedrailwaywasbuiltinJapanin1964,morethantencountriesandregionshavedevelopedhigh-speedrailways,operatingoveratotalofmorethan10000km.High-speedrailwaysnotonlyprovidethepublicwithanewtypeofrapid,convenient,safe,andcomfortabletravel,butalsogreatlyboostthesocio-economicdevelopmentofthecountry.

  • 标签: 铁路技术 中国 铁路运输 能源消耗 环境问题 海上运输
  • 简介:Itislearnedfromthe2013SummitForumonStrategicDevelopmentofCoal-to-NaturalGasinChinathattheChinaSedinEngineeringCompany,Ltd.hasdevelopedwithindependentintellectualpropertyrightstwoexperimentalfurnacesforpressurizedgasificationofcrushedcoal,5min

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