简介：畦到⑨天摩大薯中国近代第一所大学硕士学位论文■■■■■■一一■～一～■■■一学科专业机械制造及其自动化作者姓名赵春引指导教师王太勇教授天津大学研究生院2004年12月ABSTRACTBASEDONTHECAK6136BNCMACHINEANDITSKNDSYSTEMASETOFOPERATINGSIMULATIONSOFTWAREBASEDONVISUALBASIC60USEDFORTHISKNDNCMACHINEHASBEENDESIGNED，WHICHCANREALIZEPROGRAMEDITING，PARAMETERSETTING，MACHINEOPERATING，PROCESSSIMULATIONATTHESAMETIME，BYTHETOOLSOFHTMLHELPWORKSHOP，MICROSOFTFRONTPAGEANDFLASH，ANONLINEHELPSYSTEMBASEDONCNCSIMULATIONHASBEENDESIGNEDTHUS，CNCSIMULATIONTEACHINGPLATFORMWITHONLINEHELPSYSTEMHASBEENESTABLISHEDWHICHCANBEUSEDFORTEACHINGANDTRAININGWITHTHEHELPOFTEACHINGPLATFORMBASEDONCNCSIMULATION，CNCTEACHINGMULTIMEDIASIMULATIONLABHASBEENDEVELOPEDTHISPAPERISCOMPOSEDOFFIVEPARTSTHERESEARCHOFCNCTECHNIQUETHATINDICATESTHEGREATNEEDSOFTHEPERSONSWHOMASTERTHETECHNIQUEOFCNC，ANDTHERESEARCHOFTEACHINGPLATFORMWITHONLINEHELPSYSTEMBASEDONNCSIMULATIONAREINTRODUCEDINTHEFIRSTPARTTHESECONDPARTPRESENTSTHECNCTEACHINGFRAMEWORK，POINTSOUTTHATTHETRADITIONALTEACHINGMODEOF‘‘BLACKBOARDPLUSCHALK’’CANNOTCULTIVATETHEPERSONSWHOCANMASTERTHETECHNIQUEOFCNC，BRINGSFORWARDTHENEWFORMSOFMULTIMEDIAANDNETWORKTEACHING，DESIGNSTHETEACHINGPLATFORMBASEDONNCSIMULATION，PUTSFORWARDTHEFRAMEOFTHECOLLECTIVITY，ANALYSESTHEFUNCTIONOFTHESYSTEMTHEVARIETY，THEFORMANDTHEPRESENTSTUDYSTATUSINQUOOFTHENCSIMULATIONAREPRESENTEDINTHETHIRDPARTANDTHEDESIGNBASEDONKNDNCMACHINEANDTHEMETHODOFMODULARIZATIONOFINTERFACESDESIGNASAWHOLEANDFUNCTIONSIMPLEMENTINDEPENDENTLY，USEDTHESOFWAREOFVB60ISALSOINTRODUCEDFURTHERMORE，ITBRINGSOUTTHEFUNCTIONOFEVERYMODULE，THETOTALCONSTRUCTIONOFCNCSIMULATIONSYSTEMTHEPROCESSANDTHEMEANSOFTHEDESIGN，THESOLUTIONOFKEYPROBLEMS，ANDTHEEXPANSIBILITYOFTHESYSTEMFUNCTIONSTHEFOURTHPARTINTRODUCESTHEONLINEHELPSYSTEMUSEDTHETECHNIQUESOFFLASH，MICROSOFTFRONTPAGEANDHTMLHELPWORKSHOPTHELASTPARTINDICATESTHECNCTEACHINGMULTIMEDIASIMULATIONLABACHIEVEDBYTHETEACHINGPLATFORMBASEDONNC

简介：南京航空航天大学硕士学位论文氧化环境下陶瓷基复合材料力学性能研究姓名王振剑申请学位级别硕士专业航空宇航推进理论与工程指导教师孙志刚201012氧化环境下陶瓷基复合材料力学性能研究IIABSTRACTCERAMICMATRIXCOMPOSITESCMCSPOSSESSHIGHTEMPERATURERESISTANCEWEARRESISTANCELOWDENSITYHAVEBROADAPPLICATIONPROSPECTSONTHEAVIATIONAEROSPACEWEAPONSENERGYOTHERAREASITISIMPTANTTOPERFMTHEINVESTIGATIONSONTHEMECHANICALPROPERTIESOFCMCSUNDEROXIDATIONCONDITIONSFTHEENGINEERINGAPPLICATIONSINTHISTHESISTHEMECHANICALPROPERTIESOFUNIDIRECTIONALFIBERREINFCEDCERAMICCOMPOSITESINOXIDIZINGENVIRONMENTWEREINVESTIGATEDTHEMECHANICALPROPERTIESOFCSICCERAMICCOMPOSITESWEREANALYZEDBYUSINGTHEMASSLOSSRATEMODELUNDERTHEOXIDATIONOFTHETEMPERATURERANGE400900℃THESHEARLAGMODELTHEMONTECARLOSIMULATIONAPPROACHTHESTATISTICALFIBERFAILUREMODELTHERESIDUALSTIFFNESSUNDERTHETEMPERATURERANGEOF400℃900℃OXIDATIONENVIRONMENTSWEREPREDICTEDTHEMICROMECHANICALMETHODSWEREUSEDTOANALYZETHERESIDUALSTRENGTHUNDEROXIDATIVESTRESSFACTSBELOWTHEMATRIXCRACKHEALINGTEMPERATURETHEREARETWOKINDSOFOXIDATIONMECHANISMCHEMICALCONTROLLEDOXIDATIONTHEDIFFUSIONCONTROLLEDOXIDATIONTHETHESISANALYZEDTHEOXIDATIONRESIDUALSTRENGTHWITHNONSTRESSSTRESSEDRESIDUALSTIFFNESSRESIDUALSTRENGTHOFACERTAINTEMPERATUREAREPREDICTEDEXPERIMENTALMETHODSWEREUSEDTOINVESTIGATETHEHIGHTEMPERATURE650℃800℃INAIROXIDATIONUNDERNONSTRESSMECHANICALPROPERTIESHIGHTEMPERATURE650℃INAIROXIDATIONBEHAVIUNDERSTRESSCOMPAREDTOTHEETICALANALYSISEXPERIMENTALRESULTSPREDICTEDEXPERIMENTALRESULTSKEYWDSCERAMICMATRIXCOMPOSITESOXIDATIONSTIFFNESSSTRENGTH，STRESS

简介：分类号UDC密级学号彳雇大季硕士学位论文论文题目双辊连铸机液压AGC系统研究论文作者方华袭亲、拳名篱蓉张德文副教授重庆大学申请学位级别硕士专业名称机械电子工程论文提交日期2003年4月30日答辩日期2003年5月30日学位授予单位重庆大学授位日期2003年月日答辩委员会主席王勇勤教授论文评阅人王勇勤教授邱良佐高工2003年4月30日英文摘要ABSTRACTTHETHICKNESSACCURACYANDSHAPEACCURACYOFSTEELSTRIPARETWOKEYQUALIVYPERFORMANCESOFSTEELSTRIPTHEYAREGREATLYIMPROVEDDUETOTHEPROGRESSANDAPPLICATIONOFROLLTHEORYANDCONTROLTHEORYAUTOMATICGAUGECONTROLAGCISONEOFTHETWOKEYTECHNOLOGIESINTHEROLLINGFIELDANDDIRECTLYAFFECTSTHEQUALITYOFSTRIPPRODUCTSTWINROLLSTEELSTRIPCASTINGISANEWSTEELSTRIPPRODUCTIONMETHODOFREPRESENTINGTHESTEELINDUSTRYTENDENCYTHUS，RESEARCHONAGCSYSTEMHASIMPORTANTTHEORETICALANDPRACTICALSIGNIFICANCETHEBASICTHEORYABOUTAGCUSEDINROLLINGMILLISSCRUPULOUSLYSTUDIEDINTHEPAPERBASEDONANOVERVIEWOFTHEPRESENTSTATUSANDPERSPECTIVESOFAGCTECHNOLOGIESTHEPAPERALSODISCUSSESTHEBASICTHEORYABOUTROLLINGPROCESS，INCLUDINGELASTICEQUATIONOFROLLINGMILL，PLASTICEQUATIONOFROLLEDPIECE，ELASTICPLASTICCURVEFIGUREANDGAUGEAVIATIONEQUATIONETCTHEMODESOFAGCARESTUDIEDINDETAIL，SUCHASTHICKNESSAGC，PRESSUREAGC，FRONTFEEDBACKAGC，TENSIONALAGC，MONITORAGC，MASSFLOWAGCAFTERANALYZINGFEATURESANDFIELDSOFAPPLICATION，THEPAPERPOINTOUTTHATONEORMOREMODESSHOULDBEUSEDINTHEAGCSYSTEM，CONSIDERINGTHETYPEOFTHEROLLINGMILLANDACCURACYREQUIREMENTSOFPRODUCTSMOREOVERITANALYZESTHECONTROLLINGMODESOFPRESSUREAGC，WHICHFREQUENTLYUSEDOI“IROLLINGMILL，INCLUDINGBISRAMODE，DECOUPLINGSETMODE，GAUGEMETERMODE，DYNAMICSETMODEANDPIDGAUGEMETERMODE，GAINSTHECHARACTERISTICSANDDYNAMICBEHAVIORSOFTHEM，WHICHPROVIDESFUNDAMENTALBASISFORTHEDESIGNOFAGCSYSTEMTHEHYDRAULICAGCSYSTEMOFTHETWINROLLCASTERHASBEENDESIGNED，BASEDONTHESTUDIESANDANALYSESMENTIONEDABOVEITCONTAINSTWOPARTIESAHYDRAULICSYSTEMANDANELECTRICCONTROLSYSTEMANELECTROHYDRAULICPOSITIONSELVOCONTROLSYSTEMISUSEDINTHEHYDRAULICSYSTEM，WHICHEAI“LPRESSDOWNTHEMILERQUICKLYANDACCURATELYTOCONTROLTHEROLLGAPTHEHYDRAULICSYSTEMISTHEBODYOFTHEWHOLLYAGCSYSTEMACCORDINGTOTHEPRESENTSTATUSOFTHEMODEMINDUSTRYINANDTHECHARACTERISTICSOFAGCSYSTEM，THEELECTRICCONTROLSYSTEMADOPMTWOLEVELCOMPUTERCONTROLSTRUCTUREPROCESSAUTOMATICSYSTEMANDBASICAUTOMATICSYSTEMTHECONTROLSTRATEGYCOMBINESPRESSUREAGCANDMONITORAGCINTHEEND，USINGTHECLASSICALMODELBUILDINGTHEORYTHEMATHEMATICMODELHASBEENESTABLISHEDBASEDONTHEMODEL，THEPAPERANALYZESTHEDYNAMICBEHAVIOROFTHEELECTROHYDRAULICSERVOSYSTEMKEYWORDSHYDRAULICAGC，PRESSDOWNMODE，CONTROLLINGMODEL，ELEETROHYDRAULICPOSITIONSELVOCONTROLIII

简介：分类号UDC0346．2621硕士学位论文基于模糊理论的疲劳损伤累积模型研究陈国军论文答辩日期2Q玺堇月2昼旦学位授予日期．2业笸主旦卜．}移‘1吣基于模糊理论的疲劳损伤累积模型研究摘要材料或构件发生疲劳破坏，主要是因为其在循环载荷作用下产生不可逆损伤，并由于损伤的不断累积而最终导致失效或破坏。因此，分析产生疲劳破坏的原因，研究和解决材料的疲劳损伤等问题，以建立合理的损伤累积模型具有重要的意义。针对疲劳损伤累积的主要特征，分析了加载顺序和材料疲劳极限衰减等两种主要因素对损伤累积的影响。对不同应力水平下对数疲劳寿命不满足正态线性GAUSS．MARKOV假设的情况，应用BOXCOX变量变换拟合法来解决三参数PSN曲线拟合问题。基于模糊数学理论阐述了模糊疲劳损伤理论，并在MINER法则的基础上，结合模糊理论推导了沙堆疲劳损伤累积模型SPFDCM。在SPFDCM基础上，进一步探讨了非均匀沙堆疲劳损伤累积模型HSPFDCM。主要研究结论如下1加载顺序和材料疲劳极限衰减均会对疲劳损伤累积产生影响低．高加载顺序下，低应力要对材料产生强化效应，延缓损伤发展；高．低加载顺序下，高应力会削弱裂纹闭合效应而增加裂纹扩展，低应力会在已形成扩展裂纹的阶段促进损伤发展。2四种材料的验证分析表明利用BOX．COX变量变换拟合法估计三参数P．S．N曲线比利用最小二乘法的拟合效果更好，拟合的相对IJ，L‘，／IL、●，盼

简介：中图分类号TG50215论文编号102870513S090学科分类号080202硕士学位论文基于灰色系统理论的数控机床热误差建模技术研究研究生姓名张伟学科、专业机械电子工程研究方向数控机床技术指导教师叶文华教授南京航空航天大学研究生院机电学院二О一三年一月NANJINGUNIVERSITYOFAERONAUTICSASTRONAUTICSTHEGRADUATESCHOOLCOLLEGEOFMECHANICALELECTRICALENGINEERINGRESEARCHONTHERMALERRMODELINGOFCNCMACHINETOOLSBASEDONTHETHEYOFGRAYSYSTEMATHESISINMECHANICALELECTRICALENGINEERINGBYZHANGWEIADVISEDBYPROFYEWENHUASUBMITTEDINPARTIALFULFILLMENTOFTHEREQUIREMENTSFTHEDEGREEOFMASTEROFENGINEERINGJANUARY2013