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2 个结果
  • 简介:1.TheState:GeneralConsiderationsScholarshavelongbeinginterestedinthestateandtherunningofit.Amongthem,therewerephilosophers,historians,sociologistsandanthropologists.WemaygoasfarbackastoConfuciusandLaoTze,ortotheGreekphilosophersPlatoandAristotle1,andifwewanttostayclosertoourtime,wecanmentiontheItalianpoliticalscientistMachiavelli,whowroteinthe16thcenturyIlPrincipe(ThePrince),

  • 标签: 结构 早期 历史学家 人类学家 哲学家 社会学
  • 简介:Inordertotesttheaccuracyoftheusually-usedfixedcalibrationfactorofthecanopyscannerofLAI-2000formeasuringtheleafareaindex(LAI),aLarixprincipis-rupprechtiiplantationwaschoseninthesmallwatershedofXiangshuihelocatedattheLiupanMountainsofNingxiaHuiAutonomousRegionofNWChina,theLAIwasmeasuredinOctober2010,aperiodfromfullcanopytothetotalfallofneedles,byusingboththeLAI-2000andlitterfallcollectionmethod.Then,acomparisonwasmadebetweentheLAIvaluesdeterminedbythelitter-fallcollectionandthatcalculatedbasedonthefiguresreadfromLAI-2000andthefixedcalibrationfactor(1.49).ItshowedthattheaverageofLAImeasurementsofthe2methodswasveryclose,withadifferenceofonly5%.However,thecalculatedLAIfromLAI-2000wasobviouslyhigherthanthetruevaluesdeterminedbylitter-fallcollectionwhenthecanopywasfullofneedles;andobviouslylowerthanthetruevaluewhenthecanopywassparseafterneedlefalling.ThereasonmaybethatLAI-2000takestheprojectionoftwigsasneedles.So,adynamiccalibrationfactorisneeded,especiallyintheseasonswhentheneedleamountandthepercentageoftwigsprojectionincrownprojectionchangequickly.Therefore,astatisticrelationinaquadraticpolynomialformbetweenthe2seriesofLAIdatawaswellfitted.ThisrelationcanbeusedforamoreaccurateestimationofLAIbasedonthedatareadfromtheeasilyusedcanopyscannerslikeLAI-2000.

  • 标签: LARIX principis-ruprechitee leaf and index LAI-2000