【機械類畢業(yè)論文中英文對照文獻翻譯】裝載機系統(tǒng)可靠性分析與優(yōu)化的意義,機械類畢業(yè)論文中英文對照文獻翻譯,機械類,畢業(yè)論文,中英文,對照,對比,比照,文獻,翻譯,裝載,系統(tǒng),可靠性分析,優(yōu)化,意義 裝載機系統(tǒng)可靠性分析與優(yōu)化的意義 裝載機是為我國"十五"和2015年長期規(guī)劃中基礎工業(yè)和基礎設施建設服務的一種重大技 術裝備，它廣泛應用于國民經(jīng)濟的眾多領域，推動國家建設事業(yè)的發(fā)展。 經(jīng)過 近 四 十年的努力，我國裝載機行業(yè)已有較大發(fā)展，但產(chǎn)品水平、規(guī)模和企業(yè)素質與發(fā)達 國家相比，從整體上分析要差十五年左右，特別是大型裝載機差距更大，與國民經(jīng)濟發(fā)展戰(zhàn)略目 標和世界科學技術飛速發(fā)展相比，遠未改變被動落后的局面，相反在技術上有進一步拉大的趨勢。 國產(chǎn)裝載機以價格低，能滿足一般土石方工程鏟運作業(yè)要求的特點，在國內(nèi)市場的占有率約為 90%1,1.國產(chǎn)裝載機的價格僅為卡特彼勒、小松同類機型的1/3，故在普通工程中有較強的競爭 力，但在國內(nèi)重點土石方1程中因可靠性差、壽命短,JL乎沒有一席之地，均被國外產(chǎn)品所壟斷。 近幾年由于國產(chǎn)裝載機的價格優(yōu)勢，每年約有近加0臺出口，約占總產(chǎn)量的1.5%。因此可以說，國內(nèi)市 場的特點是廈點工程中國產(chǎn)機進不去，搬工程中進口機賣不動。 上述說明，在結構性能和結構 件加工能力方面，國產(chǎn)裝載機行業(yè)進步較快，已接近國外先進水平，但在發(fā)動機、主要傳動件方面， 因故障率高制約了產(chǎn)品總體質量和技術水平的提高。 盡管每年有不少新產(chǎn)品問世，但它們的傳動部 分大同小異，因而質量水平也大同小異。 因此，選用技術性能先進的傳動系統(tǒng)，淘汰不符合國家有關 標準的、落后的傳動件將是提高裝載機產(chǎn)品質量的關鍵。 "裝 載 機 系統(tǒng)的模糊可靠性分析"是將裝載機作為一個系統(tǒng)進行研究，用系統(tǒng)的觀點和方法 對各子系統(tǒng)的可靠性進行分析，合理分配可靠度，使系統(tǒng)的可靠度得以優(yōu)化配置，從而提高整機 的可靠性。 "輪邊減速器的可靠性優(yōu)化設計"是采用可靠性優(yōu)化設計這一現(xiàn)代設計方法，使裝載 機輪邊減速器這一關鍵部件的可靠性得以保證，使傳統(tǒng)設計方法的固有缺陷得以克服。 由于 可 靠 性對裝載機市場競爭力的重要性，國內(nèi)外學術界和工業(yè)界都很重視這方面的研究。 發(fā)達國家在理論上不斷推陳出新，在實踐中，積累了豐富的經(jīng)驗，打下了堅實的基礎，使其產(chǎn)品 可靠性大大領先其他國外同行。 同時，我國在該領域，理論上還不完善，實踐中缺乏大量基礎性 工作的支持，產(chǎn)品可靠性落后。 1--2可靠性研究的發(fā)展和研究內(nèi)容 、可靠性學科的產(chǎn)生與發(fā)展概況 第二 次 世 界大戰(zhàn)期呵，德國在改進其v- I和v-I t火箭性能時就提出了可靠性的概念。 美 國的海、陸、空軍等部門，由于其技術裝備經(jīng)常發(fā)生故障而不能有效利用，于1945年至1950年 進行了大量的關于可靠性方面的研究。 當時，美國派往前線作戰(zhàn)的飛機有B0%不能起飛，電子儀 廣西大學碩士學位論文 器使用時50%發(fā)生故障，轟炸機上電子裝置的正常工作時間平均只有20小時，海軍艦艇上的電子 裝置在使用初期有70%發(fā)生故障。電子裝置的高故障率引起了人們的高度重視，從而促進了可靠 性研究首先在電子學領域得到快速發(fā)展。 195 4 年在 紐約成立了第一個美國國家可靠性委員會，英國、前蘇聯(lián)、日本等國家相繼從20 世紀50年代末開始了可靠性研究工作。 第一 階 段 (1943至1958年)，主要描述了建立在指數(shù)分布規(guī)律基礎上的平均壽命的概率統(tǒng)計 特性。 研究認為，產(chǎn)品故障的發(fā)生及其原因是隨機事件，具有不可避免性。 第二 階 段 (1958至1968年)，可靠性研究的特點是，大力開展了實際可靠性的試驗評估，以 及可靠性信息的收集和處理工作。 經(jīng)過這一階段的研究，使可靠性研究工作從電子領域擴展到了 機械領域，從軍事部門擴展到了民用部門。 196 8年 以 后是可靠性發(fā)展的第三階段。 在這一階段，可靠性數(shù)學理論得到了進一步的發(fā)展， 并使其與技術學科緊密結合，形成了可靠性試驗方法與數(shù)據(jù)處理方法;頒布了有關可靠性標準。 建立了預防維修體系和可靠性管理機構，并使可靠性的教育更加普及。 我國 自 1950年以來，原機械工業(yè)部有關單位對可靠性進行了研究，出版了《可靠性與環(huán)境 試驗》和《國外電子產(chǎn)品可靠性與環(huán)境試驗》兩種刊物。 以后又在廣州設立了環(huán)境試驗研究所。 自1978年改革開放以來，我國的可靠性研究得到了大力發(fā)展，許多行業(yè)相繼設立了可靠性專業(yè) 組織，制定了相應的可靠性標準，加強了產(chǎn)品可靠性考核與管理工作。 經(jīng)過 20 多年的努力，我國工程機械領域在產(chǎn)品可靠性研究方面取得了較大的成績。 對批量 生產(chǎn)的工程機械產(chǎn)品制定相應的可靠性指標和可靠性試驗標準，高等院校的相關專業(yè)開設了可靠 性課程并進行專題研究，從而促進了工程機械產(chǎn)品質量的不斷提高。 二 、 可 靠性研究的內(nèi)容 可靠 性 學 科研究領域十分廣闊，分為三個基本方面，即:可靠性基礎理論、可靠性工程和可 靠性管理。 可靠 性 基 礎理論包括可靠性數(shù)學和失效學兩個領域。 概率論與數(shù)理統(tǒng)計是可靠性研究的理論 基礎。 可靠 性 工 程和可靠性管理包括:1.可靠性指標的確定與分配;2.可靠性預測:3.可靠性設計; 4制造可靠性;5.可靠性試驗:6.可靠性鑒定;7.使用可靠性;8.可靠性管理。 隨著 科 學 技術的發(fā)展，工程機械產(chǎn)品的技術水平不斷提高，用戶對產(chǎn)品的可靠性要求也越來 越高，產(chǎn)品的可靠性水平直接影響著用戶的經(jīng)濟效益，并成為產(chǎn)品競爭力的關鍵因素。 因此，工 程機械可靠性理論研究將受到越來越高的重視，可靠性研究也將更加深入。 機械系統(tǒng)可靠性設計 與傳 統(tǒng) 設 計方法相比，可靠性設計有其自身的特點。 在傳統(tǒng)設計中，認為應力、強度、安全 系數(shù)等是確定性的單值變量:而在可靠性設計中，將相應的變量處理成多值的隨機變量，并服從 __廣西大學碩士學位論文 器使用時50%發(fā)生故障，轟炸機上電子裝置的正常工作時間平均只有20小時，海軍艦艇上的電子 裝置在使用初期有70%發(fā)生故障。電子裝置的高故障率引起了人們的高度重視，從而促進了可靠 性研究首先在電子學領域得到快速發(fā)展[z] 195 4 年在 紐約成立了第一個美國國家可靠性委員會，英國、前蘇聯(lián)、日本等國家相繼從20 世紀50年代末開始了可靠性研究工作。 第一 階 段 (1943至1958年)，主要描述了建立在指數(shù)分布規(guī)律基礎上的平均壽命的概率統(tǒng)計 特性。 研究認為，產(chǎn)品故障的發(fā)生及其原因是隨機事件，具有不可避免性。 第二 階 段 (1958至1968年)，可靠性研究的特點是，大力開展了實際可靠性的試驗評估，以 及可靠性信息的收集和處理工作。 經(jīng)過這一階段的研究，使可靠性研究工作從電子領域擴展到了 機械領域，從軍事部門擴展到了民用部門。 196 8年 以 后是可靠性發(fā)展的第三階段。 在這一階段，可靠性數(shù)學理論得到了進一步的發(fā)展， 并使其與技術學科緊密結合，形成了可靠性試驗方法與數(shù)據(jù)處理方法;頒布了有關可靠性標準。 建立了預防維修體系和可靠性管理機構，并使可靠性的教育更加普及。 我國 自 1950年以來，原機械工業(yè)部有關單位對可靠性進行了研究，出版了《可靠性與環(huán)境 試驗》和《國外電子產(chǎn)品可靠性與環(huán)境試驗》兩種刊物。 以后又在廣州設立了環(huán)境試驗研究所。 自1978年改革開放以來，我國的可靠性研究得到了大力發(fā)展，許多行業(yè)相繼設立了可靠性專業(yè) 組織，制定了相應的可靠性標準，加強了產(chǎn)品可靠性考核與管理工作。 經(jīng)過 20 多年的努力，我國工程機械領域在產(chǎn)品可靠性研究方面取得了較大的成績。 對批量 生產(chǎn)的工程機械產(chǎn)品制定相應的可靠性指標和可靠性試驗標準，高等院校的相關專業(yè)開設了可靠 性課程并進行專題研究，從而促進了工程機械產(chǎn)品質量的不斷提高。 二 、 可 靠性研究的內(nèi)容 可靠 性 學 科研究領域十分廣闊，分為三個基本方面，即:可靠性基礎理論、可靠性工程和可 靠性管理。 可靠 性 基 礎理論包括可靠性數(shù)學和失效學兩個領域。 概率論與數(shù)理統(tǒng)計是可靠性研究的理論 基礎。 可靠 性 工 程和可靠性管理包括:1.可靠性指標的確定與分配;2.可靠性預測:3.可靠性設計; 4制造可靠性;5.可靠性試驗:6.可靠性鑒定;7.使用可靠性;8.可靠性管理。 隨著 科 學 技術的發(fā)展，工程機械產(chǎn)品的技術水平不斷提高，用戶對產(chǎn)品的可靠性要求也越來 越高，產(chǎn)品的可靠性水平直接影響著用戶的經(jīng)濟效益，并成為產(chǎn)品競爭力的關鍵因素。 因此，工 程機械可靠性理論研究將受到越來越高的重視，可靠性研究也將更加深入。 機械系統(tǒng)可靠性設計 與傳 統(tǒng) 設 計方法相比，可靠性設計有其自身的特點。 在傳統(tǒng)設計中，認為應力、強度、安全 系數(shù)等是確定性的單值變量:而在可靠性設計中，將相應的變量處理成多值的隨機變量，并服從 廣西大學碩士學位論文 一定的概率統(tǒng)計分布。 在計算方法上，傳統(tǒng)設計采用確定性的計算公式，而可靠性設計采用非確 定性的計算公式。 在設計準則方面，傳統(tǒng)設計以確定的許用應力和安全系數(shù)為準則;而在可靠性 設計中，是以強度大于應力的概率為準則。 即，傳統(tǒng)設計是一種確定性的，以靜態(tài)數(shù)據(jù)為基礎的 經(jīng)驗設計;可靠性設計則是一種非確定性的，以統(tǒng)計數(shù)據(jù)和概率論為基礎的合理設計。 系統(tǒng) 可 靠 性設計，指的是整機系統(tǒng)可靠性的總體設計。 設計奠定可靠性，說明整機系統(tǒng)的可 靠性設計，是決定整機系統(tǒng)能否優(yōu)生，能否保證可靠性水平的關鍵。 整機系統(tǒng)的可靠性設計是以 現(xiàn)場實際使用條件和使用要求為依據(jù)，以保證和提高整機系統(tǒng)在現(xiàn)場使用條件下順利完成規(guī)定功 能的能力為目的。 然而，可靠性設計的出發(fā)點是從如何滿足經(jīng)過論證的可靠性指標開始。 整機 系 統(tǒng) 的可靠性設計是整機系統(tǒng)總體工程設計的組成部分，它與整機系統(tǒng)的結構設計緊密 相連相互交錯。 可靠性設計指標是一個獨立的要求，是保證整機系統(tǒng)質量與可靠性水平的重要的 技術指標。 然而，對整機系統(tǒng)的可靠性設計方案與可靠性設計的各項要求，又是寓于整機系統(tǒng)的 結構中的。 因此，要設計一個先進的裝備，不僅要有先進的功能與性能的總體方案，還要有一個 完善的可靠性設計總體方案。 事實證明，整機系統(tǒng)有無可靠性設計總體方案，以及可靠性方案成 功與否，是決定整機系統(tǒng)成敗的關鍵因素，無論是從節(jié)省人力、物力、降低成本方面看，還是從 加速試制進度，保證產(chǎn)品質量與可靠性水平方面看，都有特別重要的意義。 機械系統(tǒng)模糊可靠性設計 以概 率 論 與數(shù)理統(tǒng)計為數(shù)學基礎的可靠性設計，一般稱之為常規(guī)可靠性設計或普通可靠性設 計，它研究工程設計中存在的隨機現(xiàn)象，本質上把工程設計中的設計變量處理成多值隨機變量， 從而對系統(tǒng)的有關參數(shù)和指標予以概率意義上的設計，把傳統(tǒng)的設計擴展到一個新水平。 然而， 可靠性設計存在隨機現(xiàn)象的同時，還存在大量的模糊現(xiàn)象。 例如經(jīng)抽象簡化的基本支座模型有三 類:固定端、簡支端和自由端，自由端有明確的定義，容易識別，但對固定端、簡支端就沒有明 顯的界限，對滑動軸承而言，軸承較寬則假設為固定端，軸承較窄則假設為簡支端，這里的"較 寬"和"較窄"都是模糊概念。 八十年代后期，國內(nèi)外有關人士認識到常規(guī)可靠性設計理論的局 限性。 常規(guī) 可 靠 性設計理論的局限性主要表現(xiàn)在以下幾個方面: 首先 ， 常 規(guī)可靠性設計理論是建立在普通集合論和二值邏輯基礎上的。 其次 ， 常 規(guī)可靠性設計理論面臨事物的復雜化與"梢確"描述事物性質和狀態(tài)的矛盾。 最后 ， 常 規(guī)可靠性設計理論缺乏必要的數(shù)據(jù)。 隨著 各 種 新型復雜系統(tǒng)的建立與工程項目的實施，常規(guī)可靠性設計理論與工程實踐的矛盾日 益突出。 由于常規(guī)可靠性設計理論對處理模糊現(xiàn)象無能為力，迫使人們將模糊數(shù)學和常規(guī)可靠性 設計結合起來。 模糊 隨 機 可靠性設計是以模糊數(shù)學、常規(guī)可靠性設計理論為基礎，同時考慮系統(tǒng)中的模糊現(xiàn) 象和隨機現(xiàn)象而提出的設計理論和方法。 模糊隨機可靠性設計可簡稱為模糊可靠性設計。 廣西大學碩士學位論文 一定的概率統(tǒng)計分布。 在計算方法上，傳統(tǒng)設計采用確定性的計算公式，而可靠性設計采用非確 定性的計算公式。 在設計準則方面，傳統(tǒng)設計以確定的許用應力和安全系數(shù)為準則;而在可靠性 設計中，是以強度大于應力的概率為準則。 即，傳統(tǒng)設計是一種確定性的，以靜態(tài)數(shù)據(jù)為基礎的 經(jīng)驗設計;可靠性設計則是一種非確定性的，以統(tǒng)計數(shù)據(jù)和概率論為基礎的合理設計。 系統(tǒng) 可 靠 性設計，指的是整機系統(tǒng)可靠性的總體設計。 設計奠定可靠性，說明整機系統(tǒng)的可 靠性設計，是決定整機系統(tǒng)能否優(yōu)生，能否保證可靠性水平的關鍵。 整機系統(tǒng)的可靠性設計是以 現(xiàn)場實際使用條件和使用要求為依據(jù)，以保證和提高整機系統(tǒng)在現(xiàn)場使用條件下順利完成規(guī)定功 能的能力為目的。 然而，可靠性設計的出發(fā)點是從如何滿足經(jīng)過論證的可靠性指標開始。 整機 系 統(tǒng) 的可靠性設計是整機系統(tǒng)總體工程設計的組成部分，它與整機系統(tǒng)的結構設計緊密 相連相互交錯。 可靠性設計指標是一個獨立的要求，是保證整機系統(tǒng)質量與可靠性水平的重要的 技術指標。 然而，對整機系統(tǒng)的可靠性設計方案與可靠性設計的各項要求，又是寓于整機系統(tǒng)的 結構中的。 因此，要設計一個先進的裝備，不僅要有先進的功能與性能的總體方案，還要有一個 完善的可靠性設計總體方案。 事實證明，整機系統(tǒng)有無可靠性設計總體方案，以及可靠性方案成 功與否，是決定整機系統(tǒng)成敗的關鍵因素，無論是從節(jié)省人力、物力、降低成本方面看，還是從 加速試制進度，保證產(chǎn)品質量與可靠性水平方面看，都有特別重要的意義。 機械系統(tǒng)模糊可靠性設計 以概 率 論 與數(shù)理統(tǒng)計為數(shù)學基礎的可靠性設計，一般稱之為常規(guī)可靠性設計或普通可靠性設 計，它研究工程設計中存在的隨機現(xiàn)象，本質上把工程設計中的設計變量處理成多值隨機變量， 從而對系統(tǒng)的有關參數(shù)和指標予以概率意義上的設計，把傳統(tǒng)的設計擴展到一個新水平。 然而， 可靠性設計存在隨機現(xiàn)象的同時，還存在大量的模糊現(xiàn)象。 例如經(jīng)抽象簡化的基本支座模型有三 類:固定端、簡支端和自由端，自由端有明確的定義，容易識別，但對固定端、簡支端就沒有明 顯的界限，對滑動軸承而言，軸承較寬則假設為固定端，軸承較窄則假設為簡支端，這里的"較 寬"和"較窄"都是模糊概念。 Loading Machine System Reliability Analysis The loading machine system reliability analysis and optimization is for our country " 15 " builds one kind of great technical equipment served with basic industry in the 2015 older in age phases planning and infrastructure , and its extensive use is in multitudinous domains of national economy , and pushes forward the development that the nation built the cause . As a result of near 40 years the effort , our country loading machine trade has had than the development greatly , but product standard , scope and enterprise character are compared with the advanced country , and following that upward the analysis will be less than about 15 years entire , especially large-scale loading machine gap is speedily developed and is compared with national economy development strategy objective and world science and technology more greatly , far away not changes the passive backward aspect , contrary there being trend bringing up further in the technology . The made in our country loading machine with price hangs down , the characteristic of satisfied general cubic meter of engineering shovel fortune school assignment requirement of ability , hence at home the owning rate of the market only 1/3, for Ka Tebi's lux and small loose same's type about for the price of made in our country loading machine of 90%1,1. has in the ordinary engineering the stronger competition power , but at home focal point cubic metre of earth and stone 1 Cheng Zhongyin's reliability is wrong and life span is short , JL does not have a location , all by abroad the product is monopolized . The near price superiority owing to the made in our country loading machine of several years have about closely adding 0 export every year , and occupy 1.5% of the gross output about . Therefore can speak , the characteristic of internal market is Xiamen . engineering China produces the machine can not to advance , and moves that in the engineering to enter port the machine not sell well . The made in our country loading machine trade advance is than fast at the aspect of structure capability and structure spare process ability to the mentioned above explanation , and has been close to the advanced standard of abroad , but at the aspect of engine and major transmission part , the barrier rate height has restricted product overall quality and technology raising of standard because of affairs . In spite of there being many new products to be published in every year , their transmission part is almost alike , thus the quality standard is also almost alike . Therefore chooses the transmission system of technical performance first-in , and wasing out not to agree with that to close the nation will be the key that raises the loading machine product quality about standard and backward transmission part . " the blurred reliability analysis loaded the machine system " being load the machine studying as a system , viewpoint and method with the system are analysed to the reliability of each sub system , and reasonably distribute reliablely spending , and makes system the reliable degree can optimize the disposition , thus raise the reliability of whole set . " the reliability while the deceleration parachute of wheel optimizes the design " is using the reliability to optimize this modern times design method of design , and makes the machine wheel loading can pledge while the reliability of these key parts of deceleration parachute , and makes the intrinsic defect of traditional design method can surmount . Owing to the fact that the reliability is to loading the machine market competition importance energetically , the research of this aspect are all attached importance to in home and abroad academic circles and industry circle verymuch . The advanced country is resonablely discussed to go up constantly to weed through the old to bring forth the new , and accumulated rich experience in practice , and has conquered the solid foundation , and makes his product reliability be in the lead colleagues of other abroads greatly . At the same time , our country is in this domain , and still imperfect in theory , being short of the support of a large number of foundation work in the practice , the product reliability is behind . Development and the research content of 1--2's reliability research and reliability branch of learning gives rise to and develops the general situation and breathes out World War II phase , and Germany has put forward the generally thought of reliability when improving his V- I and V-I's T's rocket capability . The department such as sea and Lu air force etc of the United States owing to his technical equipment frequently breaks down and can not effectively use , research aspect in 1945 Nian Zhi being in progress a large number ofly in 1950 about the reliability . Then , the plane of United States group thread operation had B0% can not take off before , and 50% breaks down during electronics apparatus Guangxi university Master academic degree thesis ware use , and the normal work time average of electronics device has only 20 hours on the bomber , and the electronics device on the navy naval ships and boats has 70% to break down at the initial stage of the use . The Gao Guzhang rate of electronics device has caused highly attaching importance to of people , thus has promoted reliability research firstly to get the quick development in the electronics domain . Founding first American nation reliability committee in New York 195 4 years , nations such as the Britain , former Soviet Union and Japan etc have begun reliability research work from in 20 centuries the 50's ends in succession . The stage 1 ( in 1943 to 1958 ) has chiefly been described the generally rate statistics property of the average life on the exponential distribution law foundation of establishment . The research is thought , and possesses unavoidable nature hence what hinders occur the product and his cause is the random event . The characteristic of reliability research is the stage ( in 1958 to 1968 ) , and the trial to have developed the real reliability is energetically assessed , as well as the collection of reliability information is worked with dealing with . As a result of the research of this stage , making reliability research work expand the mechanical domain from the electronics domain , enlisting , the matter department has expanded the for civil use department . Is later on the third stage of reliability development in 196 8 years . In this stage , the reliability mathematics theory has got the development further , and makes his closely combine with the technology branch of learning , and has formed reliability trial method and data handling method ; Issue the concerned reliability standard . Has built preventive maintenance system and reliability management organization , and make the education of reliability be universalized in more further . Our country is from 1950 , and primary machine building ministry has been in progress research about the unit to the reliability , and has published two kinds of publications << reliability and environmental test >> and << abroad electronic product reliability and environmental tests >> . Establish the environmental test research institute in Guangzhou again later on . The reliability research of our country has got energetically and has developed from reform and open in 1978 , and many trades have been establish reliability special interest group and are weaved in succession , and has laid down the corresponding reliability standard , and have strengthened the product reliability examining and manage work . As a result of the effort of 20 many yearss , the bigger result has been gained in the mechanical domain of our country engineering at the aspect of product reliability research . To the corresponding reliability quota of mechanical product formulation of engineering and the reliability trial standard of batch process , reliability course advance side by side line special subjects research has been opened to the correlation specialty of colleges and universities , thus has promoted constantly raising of mechanical product quality of engineering . Namely it is very vast that the content reliability branch of learning of two , reliability research is studied the domain , is divided into three basic aspects Reliability basic theory , reliability engineering and reliability management . The reliability basic theory includes reliability mathematics and inefficacy two domains . The probability theory is theory foundation of reliability research with the mathematical statistics . Reliability engineering and reliability management include : 1. the reliability quota is fixed with distributing surely ; 2. the reliability forecasting : 3. the reliability design ; 4 manufacturing reliability ; 5. the reliability trial : 6. the appraisal reliability ; 7. the use reliability ; 8. the reliability management . Along with the development of science and technology , the technology standard of mechanical product of engineering is constantly raised , and user asks also more and more highlyer to the reliability of product , and the reliability standard of product is directly influencing the economic performance of user , and becomes the key factor that the product was competed power . Therefore the mechanical reliability theory research of engineering will suffer attaching importance to of more and more higher , and reliability research also will be gone deep into more further . ' the design method is compared the mechanical system reliability design of 1-3 with the tradition , and the reliability design has his self the characteristic . Thinks that stress , intensity and fail-safe system etc are the singulary variables of certainty in the tradition design : And the variable that generals and ministers of state answers is dealt with the random variable into the multivalue in the reliability design , and obeys _ 50% during Guangxi university Master academic degree thesis ware use is broken down , and the normal work time average of electronics device has only 20 hours on the bomber , and the electronics device on the navy naval ships and boats has 70% to break down at the initial stage of the use . The Gao Guzhang rate of electronics device has caused highly attaching importance to of people , thus having promoted the most before all others quick the develops [ Z ] getting in the electronics domain of reliability research to found first American nation reliability committee in New York 195 4 years , and nations such as the Britain , former Soviet Union and Japan etc have begun reliability research work from in 20 centuries the 50's ends in succession . The stage 1 ( in 1943 to 1958 ) has chiefly been described the generally rate statistics property of the average life on the exponential distribution law foundation of establishment . The research is thought , and possesses unavoidable nature hence what hinders occur the product and his cause is the random event . The characteristic of reliability research is the stage ( in 1958 to 1968 ) , and the trial to have developed the real reliability is energetically assessed , as well as the collection of reliability information is worked with dealing with . As a result of the research of this stage , making reliability research work expand the mechanical domain from the electronics domain , enlisting , the matter department has expanded the for civil use department . Is later on the third stage of reliability development in 196 8 years . In this stage , the reliability mathematics theory has got the development further , and makes his closely combine with the technology branch of learning , and has formed reliability trial method and data handling method ; Issue the concerned reliability standard . Has built preventive maintenance system and reliability management organization , and make the education of reliability be universalized in more further . Our country is from 1950 , and primary machine building ministry has been in progress research about the unit to the reliability , and has published two kinds of publications << reliability and environmental test >> and << abroad electronic product reliability and environmental tests >> . Establish the environmental test research institute in Guangzhou again later on . The reliability research of our country has got energetically and has developed from reform and open in 1978 , and many trades have been establish reliability special interest group and are weaved in succession , and has laid down the corresponding reliability standard , and have strengthened the product reliability examining and manage work . As a result of the effort of 20 many yearss , the bigger result has been gained in the mechanical domain of our country engineering at the aspect of product reliability research . To the corresponding reliability quota of mechanical product formulation of engineering and the reliability trial standard of batch process , reliability course advance side by side line special subjects research has been opened to the correlation specialty of colleges and universities , thus has promoted constantly raising of mechanical product quality of engineering . Namely it is very vast that the content reliability branch of learning of two , reliability research is studied the domain , is divided into three basic aspects Reliability basic theory , reliability engineering and reliability management . The reliability basic theory includes reliability mathematics and inefficacy two domains . The probability theory is theory foundation of reliability research with the mathematical statistics . Reliability engineering and reliability management include : 1. the reliability quota is fixed with distributing surely ; 2. the reliability forecasting : 3. the reliability design ; 4 manufacturing reliability ; 5. the reliability trial : 6. the appraisal reliability ; 7. the use reliability ; 8. the reliability management . Along with the development of science and technology , the technology standard of mechanical product of engineering is constantly raised , and user asks also more and more highlyer to the reliability of product , and the reliability standard of product is directly influencing the economic performance of user , and becomes the key factor that the product was competed power . Therefore the mechanical reliability theory research of engineering will suffer attaching importance to of more and more higher , and reliability research also will be gone deep into more further . ' the design method is compared the mechanical system reliability design of 1-3 with the tradition , and the reliability design has his self the characteristic . Thinks that stress , intensity and fail-safe system etc are the singulary variables of certainty in the tradition design : And the variable that generals and ministers of state answers is dealt with the random variable into the multivalue in the reliability design , and obeys the Guangxi university fixed generally rate statistical distribution of Master's academic degree thesis . In the computational method , the calculation formula of certainty is used in tradition design , and the calculation formula of nondeterminacy is used in the reliability design . The tradition design takes definite allowance stress and fail-safe system as the norm at the aspect that design the norm ; And is that the generally rate that is more than stress with intensity is the norm in the reliability design . Namely , the tradition design is one kind of certainty , the experience design that takes the static state data as the foundation ; But the reliability design is one kind of nondeterminacy , and the reasonable design that the probability theory is the foundation with the statistics data . The system reliability design indicates the system design of whole set system reliability . The reliability is established in the design , explaiing the reliability design of whole set system , and is deciding the whether the most excellent life of whole set system , and the key of whether guaranty reliability standard . The reliability design of whole set system is real using the conditional sum to use and asks to the basis with the field , with the guaranty is the purpose with the ability to raise the whole set system smooth regulation accomplishing merit under the field use condition ability . But the starting point of reliability design is satisfying the reliability quota passing the demonstration from how to begin . The reliability design of whole set system is the component of whole set system overall engineering designation , and the physical design of it and whole set system closely is linked together and interlocks mutually . The reliability design quota is the requirement of independence , and is the important technology quota to pledge whole set system quality and the reliability standard . But , to the reliability design scheme of whole set system and all requirements of reliability design , again in the structure of the whole set system containeding in . Therefore will design the equipment of a first-in , and not only will have the overall scheme of the merit ability of first-in and capability , and still will have a perfect reliability design overall scheme . The fact is proved , the scheme that the whole set system has or not reliability design overall , as well as whether or not the reliability scheme is succeeded , and is the key factor to decide the whole set system success or failure , sees no matter being the manpower from economizes and the resource and reduction cost that still from quickening the trial-production rate of progress , the guaranty product quality is seen with horizontal of reliability , and all has the especially important meaning . The reliability design is blured with the reliability design with the mathematical statistics foundation of probability theory to the mechanical system of 1-4 , and generally calling it convention reliability design or ordinary reliability design , it studies random phenomena that exists in the engineering designation , deals with the design variable in the engineering designation into the multivalue random variable in the essence , thus the design in the justice is given generally as one pleases to the concerned parameter and the quota of system , a new standard is expanded in the design of handle tradition . But the reliability design exists the at the same time of random phenomena , and still exists a large number of blurring effects . Such as there are 3 kinds through abstracting the basic abutment model simplified : Holding solid deciding the end and Jian Zhiduan and free , freely holding has the clear and definite definition , easily recognition , but as far as decide the end admittedly and Jian Zhiduan does not have the clear demarcation line , to the sliding bearing , but the bearing than the width supposes for solid decide end , but the bearing narrower hypothesis for Jian Zhiduan , here " comparatively wide " and " narrower " all is the fuzzy concept . The concerned personage of home and abroad knew the limitations of convention reliability design theory in the 80's later periods . The limitations of convention reliability design theory chiefly shows at the aspect that following several : Firstly , the convention reliability design theory is built on ordinary set theory and two-valued logic foundation . Next the convention reliability design theory is faced with complicatedization of thing and " the tip the is true " description thing quality and the contradiction of state . Finally , the convention reliability design theory is short of the necessary data . The convention reliability design theory is protruding increasingly with the contradiction of engineering practice to the implementation of establishment