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  • 简介:Thisisanaccountofthechangesinfunding,administration,andmanagementoftheBritishGeologicalSurvey(BGS),theoldestgovernment-fundedgeologicalsurveyintheworld,fromtheearly1980sto2000.Itwillintereststudentsofpublicadministration,historiansofscienceandgeologicalsurveys,andthosewhohavefollowedtheconvolutedrecenthistoryofBGS.PeterAllenhasrenderedamostvaluableserviceindocumentinganddescribingasaninsider(heonlyrecentlyretiredfromapositionasAssistantDirector)thestrugglestomaintaintheSurveyanditsprimeroleofdiscovering,

  • 标签: 地质勘测 资源浪费 效益评估 地图测绘
  • 简介:可扩展的标注语言(XML)为在基于万维网的应用代表并且互换数据成为了事实上的标准。并且XML看法,为指定用户的一扇虚拟窗户,广泛地被使用了。在实际系统,当他们需要通过看法更新来源数据时,用户们遇到所谓的看法更改问题。很长时间,看法更改问题是在数据库社区的一个待研究的问题。与各种各样的数据模型的开发,相应看法更改问题广泛地被研究了。在这篇论文,我们介绍看法更改问题的概念。我们调查并且比较以前的途径。特别,我们强调语义的角色。在XML上下文集中于这个问题,我们给讨论并且建议一个框架,它在看法定义时间收集语义信息。为实现这个框架的一些相关技术进一步被介绍。

  • 标签: XML视图 可扩展标记语言 视图更新 应用程序 语义信息 虚拟窗口
  • 简介:SurveyonChineseweldingconsumables¥ZHAOLisan(HarbinResearchInstituteofWelding(150080))Abstract:InChina,themainproductsofweldin...

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  • 简介:TheprocessandcharacteristicsofChina'spopulationchangeareuniqueintheworld.Inthepast60years,Chinahasnotonlyexperiencedthepeaksandbustsofthesizeobirths,butalsotheradicalfluctuationofthetotalnumberofdeaths,andlargepopulationmigrationandmovementEspeciallyinthelast30yearsafter

  • 标签: 中国 调查报告 家庭 人口变化 人口迁移 独生子女
  • 简介:FromDecember1998toJune1999,theChinaMarketSupervisionundertheStateStatisticsBureauconductedsurveysontheconsumptiontrendsandlivesofChina’surbanresidentsamong5,000consumersin20cities,includingBeijing,Shanghai,Chengdu,Guangzhou,Wuhan,Naming,Qingdao,Dalia...

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  • 简介:在反馈控制循环的通讯网络的插入做分析;一个网络控制系统的设计更复杂,;导致降级的一些问题控制系统的性能;甚至引起系统不稳定性。主要方面与导致网络的延期集中于网络控制系统(NCS)的稳定性分析,数据包退学学生,;多重包的传播。这些问题必须在NCS的设计被考虑。这个工作总结主要研究结果,;对一些相关处理途径评论;技术。调查的主要目的NCS是介绍新研究州的;指出未来工作的一些领域。

  • 标签: 网络控制系统 信息包损耗 网络感应延迟 计算机
  • 简介:Adigitalwatermarkingtechniqueisamulti-scientificdisciplinewhichisdevelopedrapidlyinlastseveralyearsfordigitalcontentprotection,suchascopyrightprotection,authenticationprotection,sourcetracing,etc.However,inrealisticscenarios,thedigitalwatermarkingsystemfacessignificantsecureissues,forexample,theattackerswanttoremove,detect,orembedillegalwatermarksignals.Therefore,theaimofthiscontributionistoillustraterecentresultsofrobustandsecurewatermarkingtothesignalprocessingcommunity,andhighlightbothbenefitsandstillopenissues.Specifically,thispaperisintendedtointroducetheconceptofsecureandrobustdigitalwatermarkingsystem,andprovidewithproblemsandtheircountermeasures.Firstofall,theclassicwatermarkmodelandcryptosystemwillbereviewedandthen,theconceptofsecureandrobustdigitalwatermarkingsystemwillbedescribed.Next,thewatermarkattackwillbeclassifiedanddescribed.Finally,somecountermeasuresthatcanhelptoimprovesecureandrobustnessareconsidered.IndexTermsCountermeasures,digitalwatermarkingsystem,robust,security,watermarkattacks.

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  • 简介:分析了符合统计要求的62篇关于肥胖的论文,发现常用治疗方法有针刺、针灸、电针、耳穴贴压、耳针、(耳穴)埋针、穴位敷贴、穴位埋藏及针灸配合其他疗法等;常用耳穴为胃、内分泌、神门、肺、脾、饥点和三焦,临床总有效率为75.8%。

  • 标签: 针刺疗法 肥胖症 中医 治疗 穴位敷贴 穴位埋藏
  • 简介:Thissurveyreviewstherecentdevelopmentofgradientdomainmeshdeformationmethod.Differenttootherdeformationmethods,thegradientdomaindeformationmethodisasurface-based,variationaloptimizationmethod.Itdirectlyencodesthegeometricdetailsindifferentialcoordinates,whicharealsocalledLaplaciancoordinatesinliterature.BypreservingtheLaplaciancoordinates,themeshdetailscanbewellpreservedduringdeformation.DuetothelocalityoftheLaplaciancoordinates,thevariationaloptimizationproblemcanbecastedintoasparselinearsystem.Fastsparselinearsolvercanbeadoptedtogeneratedeformationresultinteractively,oreveninreal-time.Thenonlinearnatureofgradientdomainmeshdeformationleadstothedevelopmentoftwocategoriesofdeformationmethods:linearizationmethodsandnonlinearoptimizationmethods.Basically,thelinearizationmethodsonlyneedtosolvethelinearleast-squaressystemonce.Theyarefast,easytounderstandandcontrol,whilethedeformationresultmightbesuboptimal.Nonlinearoptimizationmethodscanreachoptimalsolutionofdeformationenergyfunctionbyiterativeupdating.Sincethecomputationofnonlinearmethodsisexpensive,reduceddeformablemodelsshouldbeadoptedtoachieveinteractiveperformance.Thenonlinearoptimizationmethodsavoidtheuserburdentoinputtransformationatdeformationhandles,andtheycanbeextendedtoincorporatevariousnonlinearconstraints,likevolumeconstraint,skeletonconstraint,andsoon.Wereviewrepresentativemethodsandrelatedapproachesofeachcategorycomparativelyandhopetohelptheuserunderstandthemotivationbehindthealgorithms.Finally,wediscusstherelationbetweenphysicalsimulationandgradientdomainmeshdeformationtorevealwhyitcanachievephysicallyplausibledeformationresult.

  • 标签: 梯度 网孔变化 测量 变形方法
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  • 简介:SurveyonbiologicalfoulingandcorrosionofvesselsINTRODUCTIONSincethesteelshellvesselscameintobeing,biologicalfoulingandcorrosio...

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  • 简介:SurveyofPremaritalPregnancyInSevenProvincesThereisanotableincreaseinpremaritalpregnancyinChina,accordingtoasamplingsurveycond...

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  • 简介:ToassistyouinopeningupChina’smarket,China’sForeignTradeprovidesservicesofChina’smarketsurvey.1.SupplyingwrittenreportsonChina’smarkets1)China’ssteelmarket,2)China’stimbermarket,3)China’scementmarket,4)China’snon-ferrousmetalsmarket,5)China’sfertilizermarket,6)China’scerealsmarket,7)China’sapplemarket,8)China’s

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