简介：Thebesthydraulicchannelsectionmakesthemaximumflowcapacityforthesameflowcross-area,andtheminimumcross-areaandwettedperimeterforthesamedischarge.Theconstructioncostcanbereducednearlytotheminimumatthesametime.Thehorizontalbottomparabolicsection(HBPsection)isacompositesection.Itisimportantfordesigntofindthebestcombinationformofthehorizontalbottomandtheparabolicsides.Thispaperstudiesthebesthydraulicsectionanditshydrauliccharacteristics.Theexplicitformulaeareproposedtodeterminethedimensionsandthebestcombinationformofthehorizontalbottomandtheparabolicsides.Theseexplicitformulaeandtheparametersmakeiteasytodesignthechannel.Itisshownthattheratiosofthesurfacewidthtothedepthandthebottomwidthtothedepthareconstantforthebesthydraulicsection.Thecomparisonswiththeclassicparabolic,rectangular,trapezoid,triangular,semi-cubicandhorizontal-bottomedsemi-cubicsectionsshowthattheHBPsectionhasthelargestflowcapacityandtheshortestwettedperimeterforthesameflowarea,andhasthesmallestflowareaforthesamedischarge.ItisindicatedthattheparabolicsidepartsofthebesthydraulicHBPsectionaredifferentfromthoseoftheclassicsection.TheresultsofthebesthydraulicsectionoftheclassicparabolicchannelcannotbeapplieddirectlytotheHBCsection.

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简介：教材内容：仁爱英语七年级上Unit2DifferentlooksTopic3一、学习目标1．复习关于颜色与衣物的单词。2．学习并总结形容词性物主代词与名词性物主代词：

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简介：ＰｒｏｌｏｇｔｏｔｈｅＳｅｃｔｉｏｎｏｎＲａｄａｒＳｙｓｔｅｍＥｎｇｉｎｅｅｒｉｎｇ￥／／ＩｎｔｈｅＥｎｇｌｉｓｈｌａｎｇｕａｇｅｗｅｈａｖｅａｎｅｘｐｒｅｓｓｉｏｎｔｈａｔｓａｙｓｉｔｉｓｐｏｓｓｉｂｌｅ＂ｔｏｌｏｓｅｓｉｇｈｔｏｆｔｈｅｆｏｒｅｓ...

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简介：Theelectricindustryisbeingtransformedfromacentralizednetworktoonethatislesscentralizedandallowsmoreconsumerinteractionintheformofasmartgrid.Thereisalsoastrongcommitmentbymostcountriestoreducegreenhousegasemissionsandglobalwarmingthroughtheuseofrenewableenergyresources.Thelocallyavailablerenewableresources,suchaswind,solar,tidal

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简介：Terahertzwaves,sittinginthegapbetweenthemiddleinfraredandmillimeterwaveregions,areknownasthelastvacantareaoftheelectromagneticspectrumthathasnotquitebeenunderstoodandbroughtintoapplications.TheTerahertzregionhasbeenthefocusofresearchworldwidesinceearly1990s.Duetotheiruniquecharacteristics,

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简介：Inthelasttwodecadestherehavebeensomecleartrajectoriesofnarrativestudy.Thecognitiveandsocialsciencesdirectionofnarrativeinvestigation,coupledwithmoretraditional,literary-orientatedtheoriesofnarrative,augmentedbyanodtonon-literarymedia,plusadashofthemorefashionableaspectsofdiscourseanalysis,hasconstituted"postclassical"narratology.ThetermwasinauguratedbyHerman(1997)andhenotesthatnarrativetheoryhas"undergonenotafuneralorburialbutratherasustained,sometimesstartlingmetamorphosis"(1999:1;see

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简介：Lyingbetweenradiofrequencyandinfraredradiation,terahertz(THz)waveencounterslotsofdifficultiestoproduce,detect,transmit,andmodulate.GreateffortshavebeenmadetoconstructTHzdevices,includingsources,detectors,switches,modulators,lenses,andfilters.However,onlymoderateprogresseshavebeenmadeinTHzgenerationanddetection.Furthermore,thedevicesandtechniquestocontrolandmanipulateTHzwavesarestillinitsinfancy.Therefore,itisstillachallengetodateto

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