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簡(jiǎn)介:學(xué)校編碼10390分類(lèi)號(hào)TS2077學(xué)號(hào)122011430074密級(jí)工程工程碩士碩士專(zhuān)業(yè)專(zhuān)業(yè)學(xué)位論文學(xué)位論文航空食品質(zhì)量安全追溯體系的應(yīng)用研究航空食品質(zhì)量安全追溯體系的應(yīng)用研究指導(dǎo)教師陳發(fā)河教授葉小琴高級(jí)工程師作者姓名鄭諾茜申請(qǐng)學(xué)位級(jí)別碩士領(lǐng)域名稱食品工程論文提交日期2014年11月6日論文答辯日期2014年12月20日學(xué)位授予單位集美大學(xué)學(xué)位授予日期答辯委員會(huì)主席陳亮論文評(píng)閱人集美大學(xué)碩士學(xué)位論文航空食品質(zhì)量安全追溯體系的應(yīng)用研究鄭諾茜3CM左右集美大學(xué)碩士學(xué)位論文航空食品質(zhì)量安全追溯體系的應(yīng)用研究鄭諾茜3CM左右
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簡(jiǎn)介:中圖分類(lèi)號(hào)V2313論文編號(hào)102870215S088學(xué)科分類(lèi)號(hào)082502碩士學(xué)位論文航空發(fā)動(dòng)機(jī)中冰片運(yùn)動(dòng)軌跡的數(shù)值模擬研究研究生姓名陳來(lái)榮學(xué)科、專(zhuān)業(yè)航空宇航推進(jìn)理論與工程研究方向葉輪機(jī)氣體動(dòng)力學(xué)指導(dǎo)教師吳鐵鷹副教授南京航空航天大學(xué)研究生院能源與動(dòng)力學(xué)院二О一五年三月NANJINGUNIVERSITYOFAERONAUTICSASTRONAUTICSTHEGRADUATESCHOOLCOLLEGEOFENERGYPOWERENGINEERINGNUMERICALSIMULATIONABOUTTHETRAJECTYOFTHESHEDDINGICEINTHEAEROENGINEATHESISINAEROSPACEPROPULSIONTHEYENGINEERINGBYCHENLAIRONGADVISEDBYASSOCIATEPROFWUTIEYINGSUBMITTEDINPARTIALFULFILLMENTOFTHEREQUIREMENTSFTHEDEGREEOFMASTEROFENGINEERINGMARCH2015
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簡(jiǎn)介:西南交通大學(xué)碩士學(xué)位論文基于人為因素的航空安全研究姓名溫濤申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)交通運(yùn)輸規(guī)劃與管理指導(dǎo)教師蒲云2001111Q1西南交通大學(xué)碩士研究生學(xué)位論文第1I頁(yè)ABSTRACTTHESAFETVOFCIVILAVIATIONISIMPORTANTTOTHENATIONALANDPEOPLE’SBENEFIT,ESPECIALLYTOTHEREPUTATIONOFNATIONTHISTHESISDISCUSSESROUNDLYONAVIATIONSAFETYFROMTHEVIEWPOINTOFAVIATIONSAFETYMANAGEMENTITINTRODUCESFIRSTTHEDEVELOPMENTANDACTUALITYOFVRORLDCIVILAVIATIONSAFETYRESEARCH,POINTSOUTEXISTINGDROBLEMSOFCIVILAVIATIONSAFETYMANAGEMENTINCHINATHETHIRDANDFOURTHCHAPTERSDISCUSSMAINLYONTHEMEASUREOFFAUITTREEANALYSISANDIT’SAPPLICATIONINAVIATIONSAFETYMANAGEMENTTHEFIFTHCHAPTERDISCUSSESROUNDLYTHEHUMANFACTORSRESEARCHANDAPPLICATIONFROMASPECTSOFHUMANFACTORSENGINEERING,CREWDECISIONANDCOORDINATION,HUMANPHYSIOLOGYANDPSYCHOLOGYNEXTTHETHESISPROPOSESTHREEMEASURESONAVIATJONSAFETYMANAGEMENTAFTERANALYZLNG1ESTABLISHESMULTICHANNELREPORTINGSYSTEMTOEXPANDTHESCOPEOFACCIDENTSTATISTICS2ESTABLISHESSOUNDACCIDENTANALYSISSYSTEMBYINTRODUCINGFAULTTREEANALYSISANDANALYZEACCIDENTFROMTHEVIEWPOINTOFHUMANFACTORS3IMPROVESHUMANFACTORSRESEARCH,DEVELOPSSAFETYMANAGEMENTCENTEREDONHUMANRESOURCESTHEFIRSTMEASURERESOLVESMAINLYTHEPROBLEMOFACCIDENTSTATISTICSTHE1ASTTWOEMPHASIZEACCIDENTANALYSISANDPREVENTIONTHEOUTCOMEOFFAULTTREEANALYSISINDICATESTHATHUMANFACTORSARETHEMOSTIMDORTANTFACTORINMODERNAVIATIONACCIDENTSSOHUMANFACTORSRESEARCHISTHEMOSTIMPORTANTTOAVIATIONSAFETY,ANDISTHEKEYSTONEOFTHISTHESISTHETHESISAIMSTOIMPROVESTANDARDOFAVIATIONSAFETYBYPROPOSINGMETHODSOFACCIDENTANALYSISANDPREVENTION1IKEYWORDSAVIATIONSAFETYACCIDENTHUMANFACTORS
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大?。?2.33(MB)
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簡(jiǎn)介:合肥工業(yè)大學(xué)碩士學(xué)位論文航空發(fā)動(dòng)機(jī)主軸軸承保持架動(dòng)平衡技術(shù)研究姓名李立堂申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)機(jī)械工程指導(dǎo)教師趙韓馬純民20030401RESEARCHONDYNAMLCBALANCETECHNOLOGYOFCAGEINEAROSPACEENGINEMANQSHAFEBEARINGABSTRACTUNDERHIGHSPEEDCONDITION,IFTHECAGEOFAEROSPACEENGINEMAINSHAFTBEAINGCAN’TBEBALANCEITSUNBALANCEWILLHAVEDETRIMENTALEFFECTONBEARING.THISWILLINFLUENCEBEARINGLIFEANDRELIABILILY.THETECHNOLOGYOFDYNAMICBALANCEOFCAGEINAEROSPACEENGINEMAINSHAFEBEARINGISWIDELYUSEDINTHEPRODUTIONINDEVELOPEDCOUNTRY.INOURCOUNTRYTHISTECHNOLOGYISSTILLAVACANT.THISPAPERANALYZETHETHEORYOFDYNAMICBALANCEOFTHECAGEBYMEANSOFPIERCINGMANDREL,ANDPERFORMDYNAMICBALANCETESTINSIMPLECAGESTRUCTURETODEMONSTRATETHEDYNAMICBALANCEFEASIBITITYOFCAGEBYMEANSOFPIERCINGMANDREL.THREEINSTALLEDTHEMETHODSRESEARCHEDANDTESTEDINTHISPAPERTOSHOWTHEASSEMBLEDAPPLIANCEOFTHECAGEISSIMPLEINSTRUCTUREANDEASYTOMOUNT.THISPAPERRESEARCHANDCONFIRMREVOLVINGPOSITIONBALANCEMETHODINREVERSEDIRECTIONWHICHISSUITABLEFORSMALLBATCHPRODUCTIONANDDEVELOPSPECIALCAGEDYNAMICBALANCEMACHINESUITABLEFORMASSBATCHPRODUCTIONOFENTERPRISE.KEYWORDSAEROSPACEENGINEBEARINGCAGEDYNAMICBALANCEDYNAMICBALANCEMACHINE
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頁(yè)數(shù): 57
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簡(jiǎn)介:學(xué)校代碼10406分類(lèi)號(hào)V2636學(xué)號(hào)120085201012南昌航空大學(xué)南昌航空大學(xué)碩士學(xué)位論文(專(zhuān)業(yè)學(xué)位研究生)基于網(wǎng)格細(xì)化小波聚類(lèi)的航基于網(wǎng)格細(xì)化小波聚類(lèi)的航空發(fā)動(dòng)機(jī)轉(zhuǎn)子系統(tǒng)故障診斷空發(fā)動(dòng)機(jī)轉(zhuǎn)子系統(tǒng)故障診斷碩士研究生丁偉明導(dǎo)師劉曉波教授申請(qǐng)學(xué)位級(jí)別碩士學(xué)科、專(zhuān)業(yè)機(jī)械工程所在單位航空制造工程學(xué)院答辯日期2015年5月授予學(xué)位單位南昌航空大學(xué)I摘要隨著我國(guó)國(guó)民經(jīng)濟(jì)實(shí)力的增強(qiáng)和國(guó)際地位的日益提高,現(xiàn)代航空事業(yè)的發(fā)展步伐逐步加快飛機(jī)發(fā)動(dòng)機(jī)性能在不斷提高的同時(shí),航空發(fā)動(dòng)機(jī)結(jié)構(gòu)設(shè)計(jì)日益繁雜,發(fā)生各種故障的概率隨之上升,所以對(duì)于它的穩(wěn)定性和可靠性的要求也會(huì)越來(lái)越高。轉(zhuǎn)子系統(tǒng)振動(dòng)故障是造成航空發(fā)動(dòng)機(jī)故障的主要原因之一,當(dāng)轉(zhuǎn)子系統(tǒng)發(fā)生故障時(shí),通常會(huì)導(dǎo)致嚴(yán)重的振動(dòng)問(wèn)題,甚至導(dǎo)致機(jī)毀人亡的事故發(fā)生。因此,對(duì)于轉(zhuǎn)子系統(tǒng)進(jìn)行故障診斷研究,不僅具有重要的學(xué)術(shù)價(jià)值,而且對(duì)國(guó)民經(jīng)濟(jì)以及國(guó)家安全都有著重要的現(xiàn)實(shí)意義。本文將小波聚類(lèi)算法作為轉(zhuǎn)子系統(tǒng)振動(dòng)故障診斷方法,在MATLAB環(huán)境下,對(duì)故障診斷準(zhǔn)確度即聚類(lèi)精度進(jìn)行分析之后,為了能夠更加準(zhǔn)確地判斷出故障類(lèi)型、提高聚類(lèi)精度,提出了網(wǎng)格細(xì)化的小波聚類(lèi)算法,即將網(wǎng)格拆分技術(shù)運(yùn)用到小波聚類(lèi)算法,對(duì)算法運(yùn)行過(guò)程中的特征空間網(wǎng)格單元進(jìn)行“網(wǎng)格細(xì)化”以此來(lái)對(duì)邊界點(diǎn)進(jìn)行提取,最后對(duì)改進(jìn)前后算法的聚類(lèi)精度進(jìn)行理論研究和實(shí)驗(yàn)驗(yàn)證。在本文中,首先闡述了課題研究的目的及意義,對(duì)于航空發(fā)動(dòng)機(jī)故障診斷的國(guó)內(nèi)外現(xiàn)狀與發(fā)展趨勢(shì)進(jìn)行了大概的描述;其次,對(duì)于航空發(fā)動(dòng)機(jī)進(jìn)行了分類(lèi),并介紹了幾種航空發(fā)動(dòng)機(jī),對(duì)于轉(zhuǎn)子系統(tǒng)振動(dòng)幾種常見(jiàn)故障的原因與故障發(fā)生時(shí)所體現(xiàn)的特征進(jìn)行了詳細(xì)介紹。第三,在了解小波聚類(lèi)算法基本原理的基礎(chǔ)上提出了改進(jìn)的具體方法,即采用網(wǎng)格細(xì)化對(duì)其進(jìn)行改進(jìn)。第四,詳細(xì)介紹了網(wǎng)格拆分技術(shù)以及選取的二維特征量。最后,介紹了轉(zhuǎn)子系統(tǒng)故障模擬實(shí)驗(yàn)裝置和幾種常見(jiàn)振動(dòng)故障的實(shí)驗(yàn)方法,進(jìn)行轉(zhuǎn)子故障模擬實(shí)驗(yàn),根據(jù)采集到的轉(zhuǎn)子故障數(shù)據(jù)來(lái)驗(yàn)證改進(jìn)后的小波聚類(lèi)算法的可行性及有效性。由實(shí)驗(yàn)結(jié)果可以得到網(wǎng)格細(xì)化小波聚類(lèi)算法比改進(jìn)前的聚類(lèi)精度更高,轉(zhuǎn)子系統(tǒng)振動(dòng)故障診斷準(zhǔn)確度更高。關(guān)鍵詞關(guān)鍵詞航空發(fā)動(dòng)機(jī),轉(zhuǎn)子系統(tǒng),小波聚類(lèi),網(wǎng)格細(xì)化,故障診斷
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簡(jiǎn)介:電子科技大學(xué)UNIVERSITYOFELECTRONICSCIENCEANDTECHNOLOGYOFCHINA碩士學(xué)位論文MASTERTHESIS(電子科技大學(xué)圖標(biāo))論文題目航空發(fā)動(dòng)機(jī)高壓渦輪轉(zhuǎn)子系統(tǒng)航空發(fā)動(dòng)機(jī)高壓渦輪轉(zhuǎn)子系統(tǒng)可靠性研究可靠性研究學(xué)科專(zhuān)業(yè)機(jī)械電子工程機(jī)械電子工程學(xué)號(hào)201221080202作者姓名王齊指導(dǎo)教師黃洪鐘教授RESEARCHONRELIABILITYOFHIGHPRESSURETURBINEROTORSYSTEMINAEROENGINESAMASTERTHESISSUBMITTEDTOUNIVERSITYOFELECTRONICSCIENCEANDTECHNOLOGYOFCHINAMAJORMECHANICALELECTRONICENGINEERINGAUTHORQIWANGADVISORPROFHONGZHONGHUANGSCHOOLSCHOOLOFMECHATRONICSENGINEERING
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簡(jiǎn)介:西北工業(yè)大學(xué)碩士學(xué)位論文航空泵用無(wú)位置傳感器無(wú)刷直流電動(dòng)機(jī)控制技術(shù)研究姓名廖東泉申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)航空工程指導(dǎo)教師馬瑞卿鄧先仲20040801西北」_業(yè)大學(xué)碩上論文摘要ABSTRACTIHISPAPERAGAINSTTHEBRUSHDCMOTORFORAVIATIONPUMPATCURRENTUSEINCHINAWHICHHASSHORTSERVICELIFELOWERRELIABILITYANDCONDITIONNOTTOSATIS行THEDEVELOPINGREQUIREMENTOFAVIATIONFIELDSTAKINGMODERNBLDCMASSUBJECTINVESTIGATEDUSESPOSITIONSENSORLESSCONTROLMETHODTOREALIZEBLDCMDRIVINGANDCLOSELOOPCONTROLFORAVIATIONPUMPOFAIRCRAFTTHISPAPERANALYSESANDSTUDIESTHEWORKPRINCIPLEOFRAREEARTHPERMANENTMAGNETICBRUSHLESSDCMOTORACROSSINGZERODETERMININGMETHODOFTHEBACKELECTROMOTIVEFORCEEMFANDTHESOFTSTARTTECHNIQUEUSINGTHEROTORPOSITIONEXAMINEDBEFORESTARINGANDREALIZESTHEEXTERNALSYNCHRONIZEDRELIABLESTARTOFMOTORTHISMETHODCANDRIVETHEPROPERWINDINGSTOPRODUCEDESIREDROTATIONANDREDUCETHESTARTTIMEINTHISPAPERADUCS12SINGLECHIPMICROCOMPUTERISADAPTEDASCORECONTROLUNITANDTHESMOOTHSWITCHINGFROMTHEEXTERNALSYNCHRONIZEDOPERATIONTOTHEOWNSYNCHRONIZEDOPERATIONISFULLYRESOLVEDBYPULSEWIDTHMODULATIONPWMMODEMEANWHILETHEINDIRECTCLOSELOOPCONTROLOFMOTORSPEEDISREALIZEDBYTHEROTORPOSITIONSENSORLESSSIGNALBYDISCOVERYOFRESEARCHACCORDINGTOCHARACTERSOFTHEAVIATIONPUMPMOTORTHISMOTORSTARTEQUALSTOTHEZEROLOADSOITVERYSUITSFORTHEAVIATIONPUMPATTHESAMETIMEBECAUSETHEMOTORUSESELECTRICCOMMUTATIONITCANOVERCOMEMANYSHORTAGESOFMACHINECOMMUTATIONOFTHESHORTNESSOFBRUSHDCMOTORTESTSSHOWTHATTHEMOTORHAVESMALLVOLUMEHIGHRELIABILITYSTABLYANDFASTSTARTABILITYSMALLSTARTCURRENTWIDERAREAOFSPEEDADJUSTINGANDHARDMACHINECHARACTERISTICITCANSATISFYALLTHEREQUIREMENTOFAVIATIONBUMPMOTORANDWILLBUILDTHEFOUNDATIONFORAPPLICATIONOFAVIATIONPUMPDRIVINGMOTORKEYWORDSAVIATIONOPERATIONPUMPSENSORLESSBRUSHLESSDCMOTOREXTERNALSYNCHRONIZEDEMFOWNSYNCHRONIZEDOPERATIONSINGLECHIPMICROCOMPUTERSPEEDCLOSELOOPCONTROL
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簡(jiǎn)介:山東大學(xué)碩士學(xué)位論文航空模型螺旋槳的氣動(dòng)性能分析姓名楊曉玲申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)機(jī)械工程指導(dǎo)教師王勇20061115山東大學(xué)1稃碩士學(xué)位論文AERODYNAMICPROPERRYANALYSIS0FAIRCRAFRMODELPROPELLERABSTRACTINORDERTOIMPROVETHEDESIGNTECHNIQUEANDTHEAERODYNAMICPERFORMANCEOFUAVPROPELLERS,MODEMCOMPUTATIONALFUILDDYNAMIESCFDISINTRODUCEDINTOTHEPROPELLERDESIGNPROCESSANDFLOWANALYSISINTHISTHESIS.MAINRESEARCHWORKCARRIEDOUTINCLUDESTHEFOLLOWINGBASEDONTHELIFTSURFACEMETHODWITHUNDISTORTEDWAKEMODEL,ALIFTSURFACEMETHODWITHAFREEWAKEMODELESTABLISHEDANDTHECOMPUTERCODETOPREDICTTHEPERFORMANCEOFPROPELLERSISDEVELOPEDINWHICHTHEVELOCITYINDUCEDBYVORTEXCOREISTAKENINTOACCOUNTANDANITERATERELAXATIONALGORITHMOFTHEFREEWAKECALCULATIONISCONSTRUCTED.EXAMPLESSHOWTHATTHENUMERICALRESULTSAREINGOODAGREEMENTWITHEXPERIMENTALDATAAVAILABLEANDTHECAPACITYISSUCCESSFULLYEXTENDEDTOHEAVYLOADEDPROPELLER.AMOREACCURATEMETHODBASEDONTHEVORTEXTHEORY,TAKINGACCOUNTOFTHEEFFECTSOFCOMPRESSIBILITYANDTHENUMBEROFBLADESISESTABLISHEDANDACOMPUTERCODEISDEVELOPED.BASEDONTHECONDITIONFORBETZ’SMINIMUMENERGYLOSS,AOPTIMALDESIGNCODEOFPROPELLERISDEVELOPED.EXAMPLEISFOUNDTOBEMUCHSATISFACTORY.BYMEANSOFTHEABOVECFDCODES,THEAERODYNAMICPERFORMANCEOFAUAVPROPELLERISEXAMINEDANDTHETECHNOGICALAPPROACHOFIMPROVINGTHEEFFICIENCYOFTHISPROPELLERISRAISED.THERESULTSOFANALYSISSHOWTHATCOMPRESSIBLEEFFECTCANMAKE9.5%TO12%REDUCTIONOFTHEPROPELLEREFFICIENCYATDESIGNPOINT.THEWAKECONTRACTIONREACHES10%ATADVANCEDRATIOOF0.2,ANDTHELOSSOFSTRONGSHOCKANDVISCOUSEFFECTDUETOTHEONLYAIRFOILCONTOURBLADESEAMSTOBETHEMAINSEASONRESPONSIBLETOTHELOWEFFICIENCYOFTHISPROPELLER.RESULTSANDEXAMPLESSUGGESTTHATTHECFDMETHODSDEVELOPEDINTHETHESIS
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簡(jiǎn)介:南昌航空大學(xué)碩士學(xué)位論文航空發(fā)動(dòng)機(jī)潤(rùn)滑系統(tǒng)通用分析軟件算法研究、數(shù)據(jù)庫(kù)及界面開(kāi)發(fā)姓名李靜申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)航空宇航制造工程指導(dǎo)教師王琦20080401南昌航空大學(xué)碩士學(xué)位論文目錄VIIIABSTRACTTHEKEYTECHNOLOGIESOFGENERALANALYSISSOFTWAREFAEROENGINELUBRICATIONSYSTEMARESTUDIEDWHICHINCLUDINGACTERISTICALGITHMOFTYPICALELEMENTFLUIDWKALGITHMGRAPHICMODELINGDATABASETHEPAPERGIVESTHERMOANALYSISALGITHMOFEACHTYPICALELEMENTINLUBRICATIONSYSTEMBASEDONTHEDESIGNCONCEPTSOFTHETYPICALELEMENTTHECOMPUTERPROCEDUREMODULEOFTHETYPICALELEMENTHASBEENDEVELOPEDINTHEPROCESSOFMODELBUILDINGTHESTRUCTURECHAMBERSOFTHESYSTEMISDIVIDEDINTODIFFERENTCOMPONENTSTHENSYMBOLIZEDBYDIAGRAMMATICSKETCHESFURTHERCONNECTEDINTOASYSTEMTHROUGHNODALSANODALPRESSURERESIDUALCRECTIONMETHODBASEDONTHEDESIGNCONCEPTSOFELEMENTNODEHASBEENUSEDINTHERESEARCHOFFLUIDWKALGITHMAFLUIDWKCALCULATIONMODULEWHICHHASRELATIVELYHIGHPRECISIONGOODCONVERGENCEHASBEENDEVELOPEDTHEWKAUTOIDENTIFICATIONTECHNOLOGYTECHNOLOGYBASEDONTHEEQUIPMENTINTERFACEMETHODHASBEENADOPTEDINTHERESEARCHOFTHEGRAPHICMODELINGTHESOFTWAREWEREDEVELOPEDONTHEPLATFMOFDELPHI7WHILEOBJECTIENTEDVISUALIZATIONTECHNOLOGYWEREADOPTEDINTHISPAPERFRIENDLYMANMACHINEINTERFACECONVENIENTDATABASEMANAGEMENTSYSTEMHASBEENSTUDIEDATTHEENDOFTHISPAPERSOMEPROJECTCASEHASBEENDISIGNEDVALIDATIONUSINGTHISSOFTWARETHEPREDICTEDRESULTSAGREEWELLWITHTHEREQUIRMENTSWHICHSHOWSTHATTHESOFTWARECANSATISFYTHEREQUIREMENTSOFENGINEERINGDESIGNANALYSISKEYWDSLUBRICATIONSYSTEMFLUIDWKALGITHMGRAPHICMODELINGWKAUTOIDENTIFICATIONNODALS
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簡(jiǎn)介:中圖分類(lèi)號(hào)THL422UDC』墊學(xué)校代碼密級(jí)碩士專(zhuān)業(yè)學(xué)位論文10533航空用7075鋁合金蠕變時(shí)效工藝及其抗腐蝕行為的研究ASTUDYONTHECREEPAGINGPROCESSINGANDCORROSIONRESISTANCEOF7075ALUMINUMALLOY作者姓名學(xué)科專(zhuān)業(yè)研究方向?qū)W院系、所指導(dǎo)教師姜玉強(qiáng)機(jī)械工程機(jī)械設(shè)計(jì)制造及其自動(dòng)化機(jī)電工程學(xué)院藺永誠(chéng)教授論文答辯日期坦生』17答辯委員會(huì)主席中南大學(xué)2014年5月航空用7075鋁合金蠕變時(shí)效工藝及其抗腐蝕行為的研究摘要現(xiàn)代航空航天裝備不斷地向著輕量化,長(zhǎng)壽命,高可靠性方向發(fā)展,服役性能也日趨極端化。研究和制造具有復(fù)雜結(jié)構(gòu)的高性能輕合金整體構(gòu)件是航空航天裝備跨越式發(fā)展的有效途徑之一。蠕變時(shí)效成形是利用鋁合金材料的蠕變特性和人工時(shí)效原理,將蠕變成形和人工時(shí)效同步進(jìn)行的一種先進(jìn)的現(xiàn)代材料成形技術(shù)。本文針對(duì)我國(guó)輕合金整體機(jī)翼壁板成形技術(shù)相對(duì)薄弱的現(xiàn)狀,研究了航空用7075鋁合金的蠕變時(shí)效特性。本文的主要研究?jī)?nèi)容和研究成果如下1通過(guò)單軸拉伸蠕變實(shí)驗(yàn),獲得了7075鋁合金的高溫蠕變特性,研究了蠕變時(shí)效工藝參數(shù)對(duì)7075鋁合金蠕變時(shí)效特性的影響規(guī)律。結(jié)果表明蠕變時(shí)效工藝參數(shù)對(duì)材料的蠕變時(shí)效行為有著顯著的影響,材料的蠕變應(yīng)變隨著蠕變時(shí)效溫度的升高和外加應(yīng)力的增大而增大。基于陳化理論和0本構(gòu)模型,建立了7075鋁合金的蠕變本構(gòu)方程,該模型可以準(zhǔn)確地描述蠕變應(yīng)變隨時(shí)間的變化關(guān)系。2通過(guò)掃描電子顯微鏡SEM和透射電子顯微鏡TEM實(shí)驗(yàn),研究了蠕變時(shí)效工藝對(duì)材料微觀組織演變的影響規(guī)律。結(jié)果表明7075鋁合金中粗大第二相A1,CUFE和MGSI和中等尺度第二相A1。。MG,CR2和A1,ZR均勻地分布在鋁基體中,蠕變時(shí)效工藝對(duì)粗大、中等尺度的第二相沒(méi)有顯著的影響;7075鋁合金中主要時(shí)效強(qiáng)化相是TF和N相,時(shí)效強(qiáng)化相隨蠕變時(shí)效溫度的升高和外加應(yīng)力的增大而逐漸析出和長(zhǎng)大;隨著蠕變時(shí)效溫度的升高和外加應(yīng)力的增大,晶界析出相由連續(xù)分布逐漸轉(zhuǎn)化為非連續(xù)分布,晶界無(wú)析出帶的寬度也逐漸增大;和無(wú)應(yīng)力時(shí)效相比,蠕變時(shí)效可以細(xì)化晶內(nèi)強(qiáng)化相,減小晶界無(wú)析出帶的寬度。3通過(guò)電化學(xué)腐蝕實(shí)驗(yàn)、剝落腐蝕實(shí)驗(yàn)和金相實(shí)驗(yàn),研究了蠕變時(shí)效工藝對(duì)7075鋁合金抗腐蝕性能的影響規(guī)律。結(jié)果表明蠕變時(shí)效工藝改變了7075鋁合金中析出相的大小和分布,進(jìn)而影響了材料的抗腐蝕性能。在實(shí)驗(yàn)的溫度范圍內(nèi),隨著蠕變時(shí)效溫度的升高,材料的抗腐蝕性能首先提高,然后降低,當(dāng)蠕變時(shí)效溫度為393K時(shí),7075鋁合金的抗腐蝕性能最好。此外,外加應(yīng)力也會(huì)影響材料的抗腐蝕性能,當(dāng)外加應(yīng)力為230MPA時(shí),材料有著較好的抗腐蝕性能。4通過(guò)以上研究發(fā)現(xiàn),當(dāng)蠕變時(shí)效溫度為393K時(shí),7075鋁合金析出相的大小和分布比較合理,材料的抗腐蝕性能較好,適合于大型輕合金整體薄壁構(gòu)件的蠕變時(shí)效成形工藝。II
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簡(jiǎn)介:青島大學(xué)碩士學(xué)位論文飛行模擬器航空地平儀控制系統(tǒng)的研究與設(shè)計(jì)姓名劉丹申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)系統(tǒng)理論指導(dǎo)教師劉勝潘松峰20050501ABSTRAETTHEPAPERDESIGNSTHECONTROLANDSIMULATIONSYSTEMOFTHELEVELFLIGHTINDICATOROFTHEFLIGHTSIMULATOR.THEFLIGHTSIMULATORISTHEFIXTUREONTHEGROUND,WHICHCALLSIMULATETHEWHOLEFLIGHTPROCESS,INCLUDINGFLYINGOFF,FLIGHTANDLANDING.THELEVELFLIGHTINDICATORISONEOFTHEINSTRUMENTSINTHECOCKPITSYSTEM,WHICHISUSEDTOINDICATETHEPITCHINGANGLEANDTHEANGLEOFSIDESLIP.THEINSTRUMENTDRIVEUSESTWOPHASEHYBRIDSTEPPINGMOTOR.INORDERTOELIMINATETHEVIBRATIONINTHELOWSPEEDCONDITIONANDTHESTEPOUTINTHEHIGHSPEEDCONDITION,THESYSTEMUSESTHESECTIONALSPEEDADJUSTMENTWHICHCOMBINESTHELINEARSPEEDADJUSTMENTWITHTHEPARABOLICONE.INADDITION,THECONTROLSYSTEMADOPTSMULTITURNABSOLUTEANGLEENCODERASTHEPOSITIONFEEDBACKMACHINEOFTHEROTORTOREALIZETHEACCURATESERVOCONTROLOFTHESTEPPINGMOTOR.THEDRIVESOFTWAREBASEDONVBCOMPLETESTHESERIALCOMMUNICATIONBETWEENTHEINSTRUMENTCONTROLCOMPUTERANDTHELEVELFLIGHTINDICATOR,REALIZESTHATTHEINSTRUMENTCONTROLCOMPUTECONTROLSTHELEVELFLIGHTINDICATOR.INADDITION,THESOFTWARECOMPLETESTHEDYNAMICDATAEXCHANGEBETWEENTHESIMULATIONSYSTEMANDTHEDRIVESOFTWARE.DESIGNTHESIMULATIONSYSTEMOFTHELEVELFLIGHTINDICATOROFTHEFLIGHTSIMULATORBASEDONTHECONFIGURATIONSOFTWARE,WHICHCANSIMULATETHEOPERATIONOFTHEINSTRUMENTANDDISPLAYTHESEPARAMETERSSUCHASTHEPITCHINGANGLEANDTHEANGLEOFSIDESLIP.SOTHESYSTEMCANMONITORANDCONTROLTHEOPERATIONOFTHELEVELFLIGHTINDICATOR.INTHISPAPER,THEHARDWAREDESIGNOFTHELEVELFLIGHTINDICATORISCOMPLETED.OTHERWISE.THESERIAICOMMUNICATIONBETWEENTHEINSTMMENTCONTROLCOMPUTERANDTHELEVELFLI【GHTINDICATORANDTHESIMULATORSYSTEMBASEDONTHEKINGVIEWAREREALIZED.THEDESIGNCALLMEETTHEDESIGNNEEDOFTHEFLIGHTSIMULATOR.THEDESIGNOFOTHERINSTRUMENTSINTHECOCKPITSYSTEMCANUSEITFORREFERENCE.KEYWORDFLIGHTSIMULATOR;LEVELFLIGHTINDICATOR;SECTIONALSPEEDADJUSTMENT;DYNAMICDATAEXCHANGE;CONFIGURATIONSOFTWARE
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簡(jiǎn)介:電子科技大學(xué)UNIVERSITYOFELECTRONICSCIENCEANDTECHNOLOGYOFCHINA碩士學(xué)位論文MASTERTHESIS(電子科技大學(xué)圖標(biāo))論文題目航空發(fā)動(dòng)機(jī)渦輪盤(pán)疲勞壽命預(yù)測(cè)航空發(fā)動(dòng)機(jī)渦輪盤(pán)疲勞壽命預(yù)測(cè)與動(dòng)態(tài)可靠性分析與動(dòng)態(tài)可靠性分析學(xué)科專(zhuān)業(yè)機(jī)械設(shè)計(jì)及理論機(jī)械設(shè)計(jì)及理論學(xué)號(hào)201121080301作者姓名張智勝?gòu)堉莿僦笇?dǎo)教師黃洪鐘黃洪鐘教授LIFEPREDICTIONANDDYNAMICRELIABILITYANALYSISOFAIRCRAFTTURBINEDISCAMASTERTHESISSUBMITTEDTOUNIVERSITYOFELECTRONICSCIENCEANDTECHNOLOGYOFCHINAMAJORMECHANICALDESGINANDTHEORYAUTHORZHANGZHISHENGADVISORPROFHUANGHONGZHONGSCHOOLSCHOOLOFMECHATRONICSENGINEERING
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簡(jiǎn)介:南京航空航天大學(xué)博士后士學(xué)位論文高頻環(huán)節(jié)航空靜止變流器研究姓名陳道煉申請(qǐng)學(xué)位級(jí)別博士后士專(zhuān)業(yè)機(jī)械電子工程指導(dǎo)教師胡育文200121ABSTRACTCIRCUITTOPOLOGIES,CONTROLPRINCIPLES,ANDKEYCIRCUITPARAMETERSDESIGNFORNOVELAVIATIONSTATICINVERTERSASIWITHHIGHFREQUENCYLINK,ANDTHEPHYSICALMODELTESTONTHEBASISOFTHEORYSIMULATIONARECARRIEDOUTINTHISRESEARCHPAPERTHEMAINCONTRIBUTIONSOFTHISWORKARESUMMARIZEDASFOLLOWS1THEAPPLICATIONPROSPECT,DEVELOPMENTANDPRESENTSTATUSFORDC/ACINVERTERSANDASIARESYSTEMATICALLYPRESENTEDDC/ACINVERTERSARECLASSIFIEDINTOTWOCIRCUITSTRUCTURESLOWFREQUENCYLINKANDHIGHFREQUENCYLINK,ANDTHEFORMERISCERTAINLYREPLACEDBYTHELATERSEVERALVALUABLECIRCUITTOPOLOGIESFORINVERTERWITHHIGHFREQUENCYLINKAREPROPOSED2CIRCUITTOPOLOGIESFAMILYOFTHEINVERTERWITHHIGHFREQUENCYPULSEDCLINKISFIRSTLYANDCREATIVELYPROPOSEDTHISINVERTERISCONSTITUTEDOFAHIGHFREQUENCYPULSEDCLINKCIRCUITANDADC/ACINVERTERBRIDGENLEHIGHFREQUENCYPULSEDCVOLTAGEFROMTHEFORLTLERCIRCUITENABLESALLPOWERTRANSISTORSOFTHELATERINVCRTERTEALIZEZVSTWOSTAGECIRCUITSHAVETHEIRSEPARATECONTROLCIRCUITTHEVOLTAGEMODEFEEDFORWARDCONTROLSTRATEGYISINTRODUCEDINTHEFORMERSTAGE,ANDTHETHREESTATEDISCRETEPULSEMODULATIONDPMHYSTERSISCURRENTCONTROLSTRATEGYISINTRODUCEDINTHEDC/ACINVERTERANEWCONCEPTOFDUTYCYCLEEXTENDEDHIGHFREQUENCYPULSEDEVOLTAGEISSECONDLYANDCREATIVELYPROPOSEDSOASTOSIMPLIFYHIGHFREQUENCYDCLINKCIRCUITTHUSTHEHIGHFREQUENCYPULSEDCLINKCIRCUITBASEDONINTERLEAVINGFORWARDCONVERTERISREPLACEDBYHIGHFREQUENCYPULSEDELINKCIRCUITBASEDONSINGLETRANSISTORFORWARDCONVERTERTHEINVERTERHASTHEMERITSSUCHASSIMPLETOPOL095SMALLBULK,LOWERWEIGHT,HIGHEFFICIENCYANDRELIABILITY111EINVERTERTOPOLOGYISVERIFIEDBYTHESIMULATION3APROTOTYPEFOR750VA27VDC/115V400HZACDUTYCYCLEEXTENDEDHIGHFREQUENCYPULSEDELINKASIISSUCCESSFULLYDESIGNEDANDDEVELOPEDTHETESTRESULTSDEMONSTRATETHATTHISPROTOTYPEHASEXCELLENTCOMPREHENSIVEPERFORMANCESSUCHASHIGHPOWERDENSITYHIGHEFFICIENCYSMALLBULK,LOWERWEIGHT,HIGHSTEADYPRECISION,F(xiàn)ASTDYNAMICRESPONSESTRONGOVERLOADANDSHORTCIRCUITABILITYANDHIGHRELIABILITY111ESTATICINVERTERHASWIDEAPPLICATIONPROSPECTTHETECHNOLOGYOFASIISADVANCEDINTHEWORLDANDLEADSINTHECHINA4THEBIDIRECTIONALPUSHPULLCURRENTMODEASLWITHHIGHFREQUENCYLINKBASEDONVOLTAGEINSTANTANEOUSVALUEFCEDBACKCONTROLISDEEPLYINVESTIGATEDAPROTOTYPEFOR250VA27VDC/LL5V400HZACASIISDESIGNEDANDDEVELOPEDBOTHTHESIMULATIONANDTHETESTRESULTSDEMONSTRATETHATTHEBIDIRECTIONALPUSHPULLCURRENTMODEASLWITHHIGHFREQUENCYLINKHASTHEMERITSSUCHASSIMPLETOPOLOGYBIDIRECTIONALPOWERF10WSMALLBULK,LOWERWEIGHT,HIGHEREFFICIENCYFASTDYNAMICRESPONSEANDHIGHRELIABILITYTHEREFORETHISINVCRTERHASGOODAPPLICATIONPROSPECTINLOWPOWERINVERSIOOFIELDS5STEADYANALYSISANDSMALLSIGNALPROPERTIESOFANACTIVECLAMPFLYBAEKCONVERTERAREDEEPLYINVESTIGATEDAPROTOTYPEFOR20W27VDC/15V1A,15V02A,5V04A,HIGHFREQUENCYSOFTSWITCHINGREGULATEDPOWERSUPPLYBASEDONTHECURRENTMODE
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簡(jiǎn)介:中南大學(xué)碩士學(xué)位論文新型航空機(jī)輪防滑剎車(chē)控制器的設(shè)計(jì)與研究姓名王敬亭申請(qǐng)學(xué)位級(jí)別碩士專(zhuān)業(yè)控制理論與控制工程指導(dǎo)教師廖力清20060509ABSTRACTAIRCRAFTANTISKIDBRAKINGCONTROLSYSTEMISONEOFTHEKEYAIRBORNEEQUIPMENTANDPLAYSAVERYIMPORTANTROLEINTHESAFETAKEOFFANDLANDINGTHEEXSITINGANTISKIDBRAKINGCONTROLLERISMOSTLYDESIGNEDWITHANALOGCIRCUIT,ANDPICONTROLMETHODISUSUALLYAPPLIEDINITSOTHEANALOGANTISKIDBRAKINGCONTROLLERHASTHEDISADVANTAGEOFLONGRESPONSETIME,BADADAPTIVEABILITYLOWCONTROLPRECISIONANDLOWBRAKEEFFICIENCYFORTHESAKEOFTHEANALOGCIRCUITITSELFITISIMPOSSIBLETOAPPLYADVANCEDCONTROLALGORITHMINTHEANALOGANTISKIDBRAKINGCONTROLLERITISVERYMEANINGFULTESEARCHANDDESIGNTHEDIGITALANTISKIDBRAKINGCONTROLLERAPPLYINGADVANCEDCONTROLALGORITHMAIMINGATTHEDISADVANTAGEOFLONGRESPONSETIME,DIGITALSIGNALPROCESSORDSPTMS320LF2407ISAPPLIEDTODESIGNDIGITALANTISKIDBRAKINGCONTROLLERANDTHESERVOVALVEISDRIVENWITHPWMPULSEWIDTHMODULATIONCONTROLMETHODAIMINGATTHEDISADVANTAGEOFBADADPTIVEABILITYFUZZYCONTROLSTRATEGYISPRESENTEDINTHEDESIGNOFSYSTEMCONTROLSTRATEGYOWINGTOTHECOMPLEXNONLINEARITYOFTHEANTISKIDBRAKINGSYSTEMANTISKIDBRAKINGFUZZYCONTROLMODELISESTABLISHED,ONTHEBASISOFWHICH,THEFUZZYCONTROLRULESANDFUZZYCONTROLLERAREDESGINEDTHEINPUTSVARIABLESOFFUZZYCONTROLLERARETHEERROROFSLIPRATEANDITSDIFFERENTIAL,ANDTHEOUTPUTVARIABLEISTHECURRENTOFTHESERVOVALVEBECAUSEFUZZYCONTROLISMAINLYBASEDONTHEEXPERIENCEOFHUMANBEING;THEOPTIMALCONTROLISDIFFICULTTOBEOBTAINEDSELFREGULATIONFACTORSAREADOPTEDINTHEFUZZYCONTROLLERTOOPTIMIZETHECONTROLRULESTHESIMULATIONRESULTSAFTEROPTIMIZATIONAREALSOSUPPLIEDINTHISPAPERTHEANTISKIDBRAKINGCONTROLLERDESIGNEDINTHISPAPERHASALREADYPASSEDTHEGROUNDINERTIATESTTHETESTRESULTSSHOWTHATTHEHARDWAREDESIGNOFTHECONTROLLERISFEASIBLE,ANDTHEFUZZYCONTROLSTRATEGYAPPLIEDINTHECONTROLLERISCORRECTANDEFFICIENTTHEANTISKIDBRAKINGCONTROLLERWORKSWELLANDRELIABLYTHEWHOLEANTISKIDBRAKINGCONTROLSYSTEMRUNSSTABLYANDTHEPERFORMANCEOFTHESYSTEMPROVEDTOBEEXCELLENTKEYWORDSANTISKIDBRAKINGSYSTEM,F(xiàn)UZZYCONTROL,SELFREGULATIONFACTORTM320LF2407ⅡI
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