简介:Avertical(laterallyaveraged)two-dimensionalhydrodynamicmodelisdevelopedfortides,tidalcurrent,andsalinityinabranchedestuarinesystem.ThegoverningequationsaresolvedwiththehydrostaticpressuredistributionassumptionandtheBoussinesqapproximation.Anexplicitschemeisemployedtosolvethecontinuityequations.ThemomentumandmassbalanceequationsaresolvedimplicitlyintheCartesiancoordinatesystem.Thetributariesaregovernedbythesamedynamicequations.Acontrolvolumeatthejunctionsisdesignedtoconservemassandvolumetransportinthefinitedifferenceschemes,basedonthephysicalprincipleofcontinuummediumoffluid.Predictionsbythedevelopedmodelarecomparedwiththeanalyticsolutionsofsteadywind-drivencirculatoryflowandtidalflow.Themodelresultsforthevelocitiesandwatersurfaceelevationscoincidewithanalyticresults.ThemodelisthenappliedtotheTanshuiRiverestuarinesystem.Detailedmodelcalibrationandverificationhavebeenconductedwithmeasuredwatersurfaceelevations,tidalcurrent,andsalinitydistributions.Theoverallperformanceofthemodelisinqualitativeagreementwiththeavailablefielddata.ThecalibratedandverifiednumericalmodelhasbeenusedtoquantifythetidalprismandflushingrateintheTanshuiRiver-TahanStream,HsintienStream,andKeelungRiver.
简介:Availablewaterandfertilizerhavebeenthemainlimitingfactorsforyieldsofspringwheat,whichoccupiesalargeareaoftheblacksoilzoneinnortheastChina;thus,theneedtosetupappropriatemodelsforscenarioanalysisofcroppingsystemmodelshasbeenincreasing.ThecapabilityofCropSyst,acroppingsystemsimulationmodel,tosimulatespringwheatgrowthofawidelygrownspringcultivar,'Longmai19',intheblacksoilzoneinnortheastChinaunderdifferentwaterandnitrogenregimeswasevaluated.Fielddatacollectedfromarotationexperimentofthreegrowingseasons(1992-1994)wereusedtocalibrateandvalidatethemodel.Themodelwasrunfor3yearsbyprovidinginitialconditionsatthebeginningoftherotationwithoutreinitializingthemodelinlateryearsintherotationsequence.CropinputparametersweresetbasedonmeasureddataortakenfromCropSystmanual.Afewcultivar-specificparameterswereadjustedwithinareasonablerangeoffluctuation.TheresultsdemonstratedtherobustnessofCropSystforsimulatingevapotranspiration,abovegroundbiomass,andgrainyieldof'Longmai19'springwheatwiththerootmeansquareerrorsbeing7%,13%and13%oftheobservedmeansforevapotranspiration(ET),grainyieldandabovegroundbiomass,respectively.AlthoughCropSystwasabletosimulatespringproductionreasonablywell,furtherevaluationandimprovementofthemodelwithamoredetailedfielddatabasewasdesirableforagriculturalsystemsinnortheastChina.
简介:摘要:随着我国经济高速发展,我国的汽车工业也快速的发展,白车身焊接车间作为汽车生产制造最重要的环节之一,对提高生产质量,缩短生产周期有着迫切的需求。基于此,本文以汽车白车身焊装工艺为研究对象,介绍了 Tecnomatix公司开发的 Process Designer、 Process Simulate软件及工艺分析新思路。
简介:四维的实验直角的功能(4D文件结束)事实上是三维的文件结束(3D文件结束)的简单联合并且扩大文件结束(EEOF),在这篇论文被提出测试数字模型的能力模仿气候和它的变化。4D-EOFanalysis能揭示分析变量,和它的相应年度、内部年度的变化的不仅水平典型模式,而且垂直结构的特征。建议的方法然后被用来分析每月吝啬的100-,500-,700-,and1000-hPa重力势高度地(4941格子和格子间距60km)并且他们的异例地in1989-1998从RMIP由MM5V3模仿了(地区性的气候为东亚为内部比较的工程建模)象他们的对应物一样的-Ⅱ,(用作观察的地)从在一样的时期的NCEP/NCARre-analysis数据集。在模仿东方亚洲气候和它的变化的MM5V3的能力被比较模仿并且观察的数据集的4D文件结束分析结果测试。比较分析结果证明观察月刊的第一特徵向量的水平模式意味着重力势高度地和它的垂直相等的barotropicfeature很好被模仿;观察每月吝啬的重力势高程异常地的开始的二特徵向量的模拟在vertical为他们的水平反常分布和重要相等的barotropic特征也是成功的很好被复制;并且而且,观察特征例如有高度的变化,每月吝啬的重力势高度/异例地的年度andinter年度的变化也是在模拟反映的井。因此,4D文件结束能包括地测试模仿气候的数字model'sability,它的变化和它在在1990年代的东亚的变化是令人满意的。
简介:摘要:近几年随着汽车工业得高速发展,由 Tecnomatix公司开发的 Process Designer/Process Simulate软件在汽车白车身焊装车间的应用越来越广泛。本文着重介绍了 Process Designer/Process Simulate软件在规划焊装生产线的思路 /方法已经软件本身的特点以及对电脑等硬件设施的需求。