简介：Asimplemethodwasdevelopedtorelatesoilsorptivitytohydraulicdiffusivityandwaterabsorptionexperimentswereconductedutilizingone-dimensionalhorizontalsoilcolumnstovalidatetherelationship.Inaddition,anestimationmethodforhydraulicdiffusivitywithdiscinfiltrometerwasdeveloped.Theresultsindicatedafavorablefitofthetheoreticalrelationtotheexperimentaldata.Also,theexperimentwithdiscinfiltrometerforestimatingthediffusivityshowedthatthenewmethodwasfeasible.

简介：１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｅｘｐｅｒｔｓｙｓｔｅｍｓａｐｐｒｏａｃｈｉｓｃｕｒｅｎｔｌｙｂｅｉｎｇａｐｐｌｉｅｄｔｏｃｏｍｐｕｔｅｒ－ａｉｄｅｄｄｅｓｉｇｎ（ＣＡＤ）ｆｏｒｓｉｍｐｌｅｈｙｄｒａｕｌｉｃｃｉｒｃｕｉｔｓ．Ｍｏｓｔｏｆｔｈｅｅｘｐ...

简介：Inthispaper,tenwoodyplantsgrewonthecampusoftheBeijingForestryUniversitywereselectedformeasuringhydraulicarchitectureparametersandwaterpotentialofone-year-oldtwigs.Theresultsshowthatdayandnightchangeofwaterpotentialandhydraulicarchitectureparametersappeartobeobviouslyconvextrend.Therelationshipmodelsbetweenwaterpotentialandhydraulicconductivity,specialconductivityandleafspecialconductivitywererespectivelyestablished,whichweresimulatedb...

简介：Throughaseriesofmodeltestsoffivescalesfor2-Dfreehydraulicjump,theda-taoffluctuatingpressureactingonthefloorlevelwithinthehydraulicjumpwereobtained.Dur-ingtheexperiments,Froudenumbervariedfrom2.94to8.61,andReynoldsnumberrangedfrom2×10~4to6×10~5.Experimentresultsindicatethattheamplitudescaleoffluctuatingpres-sureisthelengthscaleofmodel,i.e.P’=L,whichagreeswithgravitysimilaritylaw:Thefrequencyscaleofthefluctuatingpressureisaunityi.e.,f=1,whichdoesnotsatisfythegravitysimilaritylaw.

简介：Travelingandstationaryinternalhydraulicjumpsindensitycurrentswithpositiveornegativeentrainmentcoefficientswereanalyzedbasedonsimpleassumptions.Anexpressionofinternalhydraulicjumpswithentrainmentcoefficientswasderived.Experimentaldata,publishedinliterature,ofstationaryinternalhydraulicjumpsinturbid,thermalandsalinedensitycurrentsincludingmeasuredvaluesofwaterentrainmentwereusedtocomparewiththeory.Comparisonwasalsomadeoftravelinginternalhydraulicjumpsbetweenmeasureddataandtheory.

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简介：TenhealthytreespecieswithregularmanagementwereselectedonthecampusofBeijingForestryUniversity,andtheybelongtotalltree,shrubandliana,respectively.Waterpotentialandhydraulicarchitectureparametersofone-year-oldtwigsweremeasuredinsunnydayinthelasttendaysofMarchtothemiddletendaysofMayin2002.Theresultsshowthatthedailychangeinwaterpotentialoftreespeciesexaminedappearsconvex,i.e.thewaterpotentialishigherinthemorningandevening,and...

简介：Thispaperpresentsananalysisofthepotentialforenginespeedreductioninhydraulicequipment,takingintoaccountnotonlytheminimumenginespeedrequiredtomeetthecurrentflowdemand,butalsotheminimumspeedcapableofacceleratingtheenginetomeetincreasedflowdemandinthenearfuture.Thisisapredictivetask,asitrequiresanestimateoftheoperator'sintentiontoincreaseflowdemand.Wepresentananalysisofthepotentialforenginespeedreductionusingaworkcyclefroma40tonexcavatorloadingatruck,whichresultsinapotential33%reductioninthemeanenginespeedwithnoreductioninusefulworkrate.Wealsopresenttwonewenginespeedcontrolalgorithmstoperformthispredictivetask.

简介：InthesouthernpartofChina,duetotherichrainfallsandfavourablytopographicallandscape,thereisabundanthydraulicenergyresourcescontainedinthecountlesssmallstreamsandriversinthemountainousandsemi-mountainousareas.Besidesthesmallhydropowergenerationwhichtransfersthepotentialenergytotheelectricalpower,thereisothertechnologyavailabletoutilisethepotentialenergydirectlyforthewaterliftingintheirrigationanddecentraliseddo-mesticwatersupplyinthevillagelevel.Thispaperintroducesthebasicprincipleofthehydraulicramop-erationanddescribestheapplicableopportunitiesforthehydraulicram.

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简介：Theartificialecologicalfloatingbediswidelyusedinriversandlakestorepairandpurifypollutedwater.However,thewaterflowpatternandthewaterleveldistributionaresignificantlychangedbythefloatingbeds,andtheinfluenceonthewaterflowisdifferentfromthatofaquaticplants.Inthispaper,basedonthecontinuousporousmediamodel,amoveabletwo-layercombinationmodelisbuilttodescribethefloatingbed.Theinfluencesofthefloatingbedsonthewaterflowcharacteristicsarestudiedbynumericalsimulationsandexperimentsusinganexperimentalwaterchannel.Thevariationsofthewaterleveldistributionarediscussedunderconditionsofdifferentflowvelocities(v=0.1m/s,0.2m/s,0.30m/s,0.4m/s),floatingbedcoveragerates(20%,40%,60%)andarrangementpositionsawayfromthechannelwall(D=0m,0.1m,0.2m).Theresultsindicatethattheflowvelocityincreasesunderthefloatingbeds,andthewaterlevelrisessignificantlyunderhighflowvelocityconditionsintheupstreamregionandthefloatingbedregion.Inaddition,theaveragerisingwaterlevelvalue(ARWLV)increasessignificantlywiththeincreaseofthefloatingbedcoveragerate,andthearrangementpositionoffloatingbedsintherivercanalsogreatlyinfluencethewaterleveldistributionunderahigh-flowvelocitycondition(v?0.2m/s).

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：在氧化的缺氧的硫化物(ASO)的最佳的操作条件生物反应器被调查。最大的移动为硫化物评价；硝酸盐被发现是4.18kg/(m[3]·d)；1.73kg/(m[3]·d)分别地。装载在固定底层集中整个减少的水力的保留时间(HRT)观察的率(LR)的volumetricalvolumetri比由在固定HRT增加底层集中的那些高。在ASO反应堆的硫化物氧化部分正在生产两硫酸盐；硫；但是生产的硫酸盐的数量是约三分之一硫的。这个过程能高容忍硫化物集中，当流入的集中直到580mg/L时，硫化物移动百分比总是在99%附近留下了。它容忍了因为当流入的集中在110mg/L上面被增加时，移动百分比落下到85%，相对降低硝酸盐集中。这个过程能容忍更短的HRT但是小心的操作被需要。自从当HRT从3.12h被减少到2.88h时，进程性能突然地败坏了，硝酸盐变换比硫化物变换对HRT更敏感。以便在反应堆避免亚硝酸根累积，流入的硫化物；硝酸盐集中应该在280mg/L被保留；67.5mg/L分别地。现在的生物工学为把硫化物从下水道移开是有用的；原油。

简介：水力的断裂是过去常从水库刺激uid生产的一种强大的技术。充分3-D水力的断裂进程的数字模拟对这种技术的effcient应用程序很重要，但是因为，也是大挑战强壮的非线性的联合在之间粘滞uid和破裂繁殖的ow。由利用一个连贯的地区方法模仿破裂过程，一个有限元素模型基于存在毛孔压力，连贯的有限元素被建立了在无限的有弹性的媒介调查塑造便士的水力的破裂的繁殖。水力的破裂行为上的连贯的材料参数和uid粘性的效果被调查了。在破裂过程被岩石破裂坚韧统治的限制案例的有限元素结果和分析答案之间的优秀同意表明连贯的地区的能力在为这个案例模仿水力的破裂生长的有限元素模型。

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简介：Inthepaper,thehydraulicarchitectureparametersofPinustabulaeformisseedlings(4yearsold)weremeasuredbyimprovedflushingmethodundernormalwaterconditioninthegreenhouseandthebasictheoryofhydraulicarchitectureisusedtodiscusstherationalityofthepipemodel.Theresultsoftheexperimentandsimulationshowthatthedifferencesofhydraulicconductivity,specificconductivityandleafspecificconductivityisgreatindifferentstemsandbranchesofPinustabulaeformisseedlings.Thehydraulicconductivityofnon-constrictionareaishigherthanthatofconstrictionarea.Thedevotionoffunctionalxylemofstemtounitleafgrowthisnotaconstant,namely,theHubervalueisdiverse.Eventhoughthepipemodelhasbeenacceptedinsomeareas,itspreconditionisnotperfect,anditishelplessincorrectlyunderstandingtheessenceofwatertransportinseedlingsfromtheprospectiveofwaterphysiology.

简介：Thefrontpartoftheflowisveryimportantandcomplexinthecaseofdebrisflowwherethereisanaccumulationoflargeboulders.Itisimportanttocontrolordampentheenergyofthefrontalpartofadebrisflowforthesafetyofthedownstreamareabecausetheimpactpressureofdebrisflowismuchgreaterthanthatofclearfluid.Themainobjectiveofthisstudyistoanalyzethehydrauliccharacteristicsoftheproposeddam(i.e.closed-typedamwithflap).Theverticalpressuredistributionofthistypeiscomparedwithconventionaldamtypes.Intheexperiments,thetotalpressureassociatedwithmajordebrisflowswasrecordedinrealtimebyasystemconsistingoffourdynamicpressuresensorsinstalledondifferenttypesofdam.Theresultsfromexperimentaldataclearlyshowthatthedamwiththeflaphasadvantagesofcapturingthedebrisflowwithlargebouldersandcontrolsthetotalpressurebyflowcirculationduetopresenceoftheflapstructurecomparedtoaclosed-typedamwithoutflap.Furthermore,theempiricalcoefficientsofhydrodynamicandsolidcollisionmodelswereproposedandcomparedwithavailablecoefficients.