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編號
無錫太湖學(xué)院
畢業(yè)設(shè)計(論文)
相關(guān)資料
題目: 偏心導(dǎo)桿調(diào)速器
信機 系 機械工程及自動化專業(yè)
學(xué) 號: 0923188
學(xué)生姓名: 趙操超
指導(dǎo)教師: 唐正寧 (職稱:副教授 )
(職稱: )
2013年5月25日
目 錄
一、畢業(yè)設(shè)計(論文)開題報告
二、畢業(yè)設(shè)計(論文)外文資料翻譯及原文
三、學(xué)生“畢業(yè)論文(論文)計劃、進度、檢查及落實表”
四、實習(xí)鑒定表
無錫太湖學(xué)院
畢業(yè)設(shè)計(論文)
開題報告
題目: 偏心導(dǎo)桿調(diào)速器
信機 系 機械工程及自動化 專業(yè)
學(xué) 號: 0923188
學(xué)生姓名: 趙操超
指導(dǎo)教師: 唐正寧 (職稱:副教授 )
(職稱: )
2012年 11月12日
課題來源
自擬題目
科學(xué)依據(jù)(包括課題的科學(xué)意義;國內(nèi)外研究概況、水平和發(fā)展趨勢;應(yīng)用前景等)
(1) 課題科學(xué)意義
調(diào)速器用于減小某些機器非周期性速度波動的自動調(diào)節(jié)裝置??墒箼C器轉(zhuǎn)速保持定值或接近設(shè)定值。水輪機、汽輪機、燃氣輪機和內(nèi)燃機等與電動機不同,其輸出的力矩不能自動適應(yīng)本身的載荷變化,因而當(dāng)載荷變動時,由它們驅(qū)動的機組就會失去穩(wěn)定性。這類機組必須設(shè)置調(diào)速器,使其能隨著載荷等條件變化,隨時建立載荷與能源供給量之間的適應(yīng)關(guān)系,以保證機組作正常運轉(zhuǎn)。調(diào)速器的理論和設(shè)計問題,是機械動力學(xué)的研究內(nèi)容。調(diào)速器的種類很多。其中應(yīng)用最廣泛的是機械式離心調(diào)速器。而以測速發(fā)電機或其他電子器件作為傳感器的調(diào)速器,已在各個工業(yè)部門中廣為應(yīng)用。
調(diào)速器的種類很多,按其工作原理的不同可分為機械式、氣動式、液動式、機械氣動復(fù)合式和電子式等多種形式。目前應(yīng)用最廣泛的當(dāng)屬機械式調(diào)速器,其結(jié)構(gòu)簡單、工作可靠、性能良好。偏心導(dǎo)桿調(diào)速器也屬于機械式調(diào)速器。
(2) 偏心導(dǎo)桿調(diào)速器的研究狀況及其發(fā)展前景
目前中國從事自動調(diào)速器生產(chǎn)的企業(yè)共有20多家,根據(jù)這些企業(yè)的已建產(chǎn)能和在建產(chǎn)能統(tǒng)計,2015年中國自動調(diào)速器產(chǎn)能將達到775萬臺。
解放初期,我國調(diào)速器事業(yè)一片空白,幾乎從零開始,大部分產(chǎn)品從蘇聯(lián)購買,少量制造亦是照搬蘇聯(lián)圖紙生產(chǎn)。50~60年代,我國調(diào)速器大部分系機械液壓型調(diào)速器。在大躍進年代,當(dāng)時的水利水電科學(xué)研究院、哈爾濱電機廠等單位曾聯(lián)合研制了我國第一臺調(diào)速器,并安裝在廣東從化流溪河水電站運行了一段時間。60年代初,當(dāng)時的水利水電科學(xué)研究院、天津電氣傳動設(shè)計研究所、長江流域規(guī)劃辦公室等單位聯(lián)合研制了我國第一臺晶體管電液調(diào)速器,并在湖北陸水試驗電站運行了相當(dāng)長一段時間。70年代至80年代初,新建的大中型水電站較多地采用了電子管、晶體管或小規(guī)模集成電路電液調(diào)速器,一些小型水電站也少量采用了電液調(diào)速器,此階段可算是機械液壓調(diào)速器與電氣液壓調(diào)速器并重。但電氣液壓調(diào)速器由于所選用的主要電子元件組件質(zhì)量不過關(guān),其長期使用的可靠性普遍較低。
研究內(nèi)容
1. 閱讀外文資料,翻譯與所學(xué)專業(yè)或課題相關(guān)的外文文獻5000字左右,語句通順、流暢、準確;
2.了解偏心導(dǎo)桿調(diào)速器的工作原理;
3.根據(jù)具體結(jié)構(gòu),擬定分析設(shè)備設(shè)計方案;
4.繪制整套零件圖,裝配圖;
5. 用Pro/E進行造型,裝配后進行運動仿真;
6. 撰寫論文,要求符合本科論文的格式要求,語言簡潔、流暢、層次分明。上機時數(shù)不少于200小時,整個畢業(yè)設(shè)計過程的技術(shù)工作要嚴謹、靈活、工作要有主動性,計算方法、計算的程序、計算結(jié)果、結(jié)論要正確。
擬采取的研究方法、技術(shù)路線、實驗方案及可行性分析
偏心導(dǎo)桿調(diào)速器主要由錐齒輪、主動鏈輪、從動鏈輪、導(dǎo)桿、曲柄、滑塊、標尺、等部分組成。其工作原理是:當(dāng)主動鏈輪輸入等角速度時,由于導(dǎo)桿和曲柄的軸心線偏置,從動鏈輪就輸出周期性的變角速度。
先松開帶柄螺母,然后轉(zhuǎn)動手柄對照標尺進行調(diào)節(jié),調(diào)節(jié)完畢后,再將帶柄螺母重新固緊。
可行性分析:通過各主要部分系統(tǒng)的確定,主要問題可以解決。細節(jié)問題也可以方便的處理,總的來說,此方案的可行性沒有問題。
研究計劃及預(yù)期成果
研究計劃:
2012年11月25日-2012年12月25日:按照任務(wù)書要求查閱論文相關(guān)參考資料,填寫畢業(yè)設(shè)計開題報告書。
2013年1月11日-2013年3月5日:填寫畢業(yè)實習(xí)報告。
2013年3月8 日-2013年3月14日:按照要求修改畢業(yè)設(shè)計開題報告。
2013年3月15日-2013年3月21日:學(xué)習(xí)并翻譯一篇與畢業(yè)設(shè)計相關(guān)的英文材料。
2013年3月22日-2013年4月11日:繪制二維零件圖。
2013年4月12日-2013年4月25日:繪制三維圖。
2013年4月26日-2013年5月20日:畢業(yè)論文撰寫和修改工作。
預(yù)期成果:
明確偏心導(dǎo)桿調(diào)速器預(yù)期達到的性能指標和工作路線??傮w方案的設(shè)計,可行性的分析。偏心導(dǎo)桿調(diào)速器的初步設(shè)計,總體結(jié)構(gòu)的設(shè)計,各部件的參數(shù)設(shè)計。強度計算,分析驗證,優(yōu)化設(shè)計。完成二維圖和三維圖的繪制。完成三維總裝圖的動態(tài)展示。完成設(shè)計說明書。
特色或創(chuàng)新之處
偏心導(dǎo)桿調(diào)速器屬于常用的機械式調(diào)速器,其結(jié)構(gòu)簡單、加工方便、安全性高。其特色在于能按刻度調(diào)節(jié)速度的大小,壽命長,不易損壞。
已具備的條件和尚需解決的問題
① 各類資料比較齊全查閱方便;
偏心導(dǎo)桿調(diào)速器已有類似的產(chǎn)品可以參考。
② 錐齒輪的計算,軸承的壽命,標尺的刻度等等。
指導(dǎo)教師意見
指導(dǎo)教師簽名:
年 月 日
教研室(學(xué)科組、研究所)意見
教研室主任簽名:
年 月 日
系意見
主管領(lǐng)導(dǎo)簽名:
年 月 日
英文原文
A knowledge-based system for materials selection in mechanical engineering design
Abstract
This paper studies various work on the development of computerized material selection system. The importance of Knowledge-based system (KBS) in the context of concurrent engineering is explained. The study of KBS in material selection in an engineering design process is described. The development in materials databases, which sometimes serve as material selection packages, is also discussed. The use of KBS in material selection and the application in the domain of polymeric-based composite are chosen as typical examples. 2001 Published by Else vier Science Ltd.
Introduction
Materials selection is a task normally carried out by design and materials engineers. Gutte ridge and Water- man [1] described the aim of materials selection as the identification of materials, which after appropriate manufacturing operations, will have the dimensions, shape and properties necessary for the product or component to demonstrate its required function at the lowest cost. For the purpose of material selection, thousands of data would be needed to characterize all the grades of materials. Many selection systems are available to help design engineers to choose the most suitable materials. At the most basic level, design engineers could use tables of material properties in data books. However, data sheets are incomplete and once published, they are difficult to update. Dadd and Fair-full [2] described how information about engineering materials, can be divided into two main categories, i.e. data and knowledge. Data is defined as the results of measurements, whereas knowledge represents the connections between items of data, the source of this knowledge, which contributes to an understanding of the results. Both the computerized database and the KBS of material selection will be described in the following sections.
The material database for materials selection
2.1. Supporting data and rigorous logic for the hypothesis and observation.
In recent years, attention is being made to the use of computer systems to store and process data regarding the properties of materials. It enables the designers to achieve large capacity and rapid retrieval from a computer database to provide easy access to the materials data.According to Prada [3], materials are the common elements enumerating parts in a product realization process. Nowadays, design engineers normally rely on the materials that they are familiar with. However, when design requirements exceed the constraints of such materials or exceed the constraints on material properties, concurrent engineering teams must consider alternative materials. With direct online access to a materials database, the concurrent engineering teams could select materials that are lighter, stronger and lower in cost. Assuming that the impact of such substitutions can be analyzed or simulated, the teams could easily make an optimum selection of materials for the available processes,conserve materials for each process and thus, reduce material waste. White [4] emphasized the importance of computer aided materials selection as books have several drawbacks as they are often outdated before reaching the bookshelves. It is very difficult to index them to find answers or to sort data in the manner of your choice. A computerized system, which provides access to materials data, is not necessarily a materials selection system, although access to data is essential to facilitate selection.
2.2. Critical review
This section reviews the development of computerized materials databases that enabled designers to select the materials in mechanical engineering design application. The development of material databases has been reported by Harmer [5] , Breuer et al [6-10], Baur [11-12] , Michael [13] , Ashby [14-15] and C ebon and Ashby [16-17] .
Harmer [5] reported that various database systems have been developed for plastics, elastomers and rubbers such as the Cambridge Materials Selector (CMS) , CAMPUS, Selector II, Specula, Cen-base/Materials, Mat. DB, Plastics Design Library .Engineered Materials Abstracts, FUNDUS, Prospector Plus, Poly mat, SPAO, Pro-Concept, Explorer, Plata’polymerically, Standards Info-disk, Piura Abstracts, Packaging Science and Technology Abstracts, Chem-In-tell and Welda-search.
Computer-aided material pre-selection by uniform standards (CAMPUS) is a widely used materials database for plastics [6-10]. A product similar to that of CAMPUS is a database concerned with the selection of long fiber reinforced plastics. This system is called FUNDUS and it allows the distribution of material information from the producer to the designer end-user [11-13]. As such, it is of interest to all who work with sheet molding compound (SMC) , bulk molding compound ?.BMC or glass-mat thermoplastic (GMT) materials as reported by Baur [11-12] and Michael i et al. [13] . CAMPUS and FUNDUS have features, which allow the user to view all properties for any listed product, print the data for any product search the database for products satisfying specific property requirements, select and view properties for comparison, and sort according to specific requirement in ascending or descending order. Ashby[14, 15] and C ebon and Ashby [16-17] developed a computerized materials selection system called Cambridge Materials Selector (CMS).
The system uses materials selection charts, which are a way of displaying material property data through the use of optimization procedures. The selection process depends on implementing performance Indices, a combination of material properties, which if maximized, optimizes performance. The charts are developed to present the materials,and the performance Indices, so that the most suitable selection of materials and shape can be carried out.
Machine Design
The complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineering material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.
The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.
If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.
A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.
中文譯文
機械工程設(shè)計選材基礎(chǔ)知識
摘要
本文致力于研究對各種材料選擇的電腦化系統(tǒng)發(fā)展。并對以基礎(chǔ)知識的系統(tǒng)在并行工程環(huán)境(KBS)的重要性進行了解釋。KBS的研究在材料選擇方面由一個工程設(shè)計過程來描述。材料數(shù)據(jù)庫的發(fā)展,和選材服務(wù),也被討論到了。在材料選擇KBS和使用中的聚合物基復(fù)合材料領(lǐng)域的應(yīng)用是選材典型的例子。2001年由Else-vier科學(xué)有限公司出版。?
1. 簡介?
材料選擇通常是設(shè)計和材料工程師一項任務(wù)。加特里奇和水人[1]中是這樣描述選擇材料的:經(jīng)過適當(dāng)?shù)闹圃鞓I(yè)務(wù),將有尺寸,形狀和性能的產(chǎn)品或組件要以最低的成本展示其規(guī)定功能的材料選擇的目標。對于選材的目的,成千上萬的數(shù)據(jù)將需要所有的材料的特性。許多選擇系統(tǒng)可以幫助設(shè)計工程師選擇最合適的材料。在最基本的層面上,設(shè)計工程師可利用材料性能數(shù)據(jù)手冊表。但是,數(shù)據(jù)表是不完整的,一旦公布,他們是難以更新。多德和范福?[2]描述了有關(guān)工程材料的資料,可分為兩大類,即數(shù)據(jù)和知識的分歧。數(shù)據(jù)被定義為測量的結(jié)果,而信息代表之間的數(shù)據(jù),在這方面的知識,這有助于對結(jié)果的認識源項目的連接。無論是計算機化的數(shù)據(jù)庫和材料選擇的KBS將在以下各節(jié)描述。??
2. 針對對材料選擇的材料數(shù)據(jù)庫?
2.1 支持這一假設(shè)的數(shù)據(jù)和嚴密的邏輯
近年來,關(guān)注正在面向計算機系統(tǒng)來存儲和處理數(shù)據(jù)的有關(guān)材料的性能。它使得設(shè)計者能夠在實現(xiàn)大容量和快速的從一個計算機數(shù)據(jù)庫里檢索到資料數(shù)據(jù)。據(jù)普拉薩德[3],材料是在列舉部分產(chǎn)品實現(xiàn)過程的共同要素。如今,設(shè)計工程師通常依賴于材料,他們所熟悉的。然而,當(dāng)超過設(shè)計要求這些材料的限制或超過材料特性的限制,并行工程團隊必須考慮替代材料。隨著直接在線訪問材料數(shù)據(jù)庫,并行工程團隊可以選擇的材料,重量更輕,更強,成本更低。假設(shè),這種替代的影響可以分析或模擬,團隊可以輕而易舉地把一個可用進程的最佳選擇材料,節(jié)約每一個程序的材料,因此,減少材料浪費是必須的。白[4]強調(diào)了計算機選型輔助材料的重要性,圖書有幾個缺點,他們往往在到達的書架得時候已經(jīng)過時。這使得他們很難找到答案指標進行排序或在您選擇的方式的數(shù)據(jù)。電腦化系統(tǒng),它提供了訪問數(shù)據(jù)的材料,并不一定是材料選擇系統(tǒng),雖然對數(shù)據(jù)的訪問是必要的,以方便選擇。??
2.2?嚴格審查??
本節(jié)回顧了計算機化的材料數(shù)據(jù)庫,使設(shè)計人員選擇了機械工程設(shè)計中的應(yīng)用材料的發(fā)展。材料數(shù)據(jù)庫的發(fā)展哈默曾報道[5],布魯爾等[6-10],鮑爾[11-12],Michael i?[13],阿什比[14-15]和C ebon和Ashby?[16-17]?。哈默[5]報道,各種數(shù)據(jù)庫系統(tǒng)已用于塑料,橡膠等材料的選擇劍橋(CMS)校園,選擇二,材料,橡膠墊發(fā)展。數(shù)據(jù)庫,塑料設(shè)計庫。文摘工程材料,眼底,勘探者另外,市產(chǎn)管辦,臨概念,探險家,普拉特的Polymers-can,標準Info-disk,皮拉文摘,包裝科學(xué)與技術(shù)文摘,化學(xué),網(wǎng)絡(luò)和搜索。?
計算機輔助材料前通過統(tǒng)一標準的選擇(CAMPUS)是一種廣泛使用的塑料材料數(shù)據(jù)庫[6-10]。一個產(chǎn)品類似CAMPUS,與長纖維選擇有關(guān)的數(shù)據(jù)庫增強塑料。這個系統(tǒng)被稱為眼底,它允許信息從材料到設(shè)計生產(chǎn)銷售的最終用戶[11-13]。因此,它是關(guān)系到所有誰與片狀模塑料(SMC)的,散裝模塑料(BMC)或玻璃墊熱塑性(GMT)的材料由鮑爾報道[11-12]和Michael i等。?[13]。校園及眼底有特點,它允許用戶查看任何列出的產(chǎn)品的所有屬性,打印任何產(chǎn)品搜索數(shù)據(jù),滿足特定性能要求,選擇和查看比較性質(zhì)的產(chǎn)品數(shù)據(jù)庫,并按照升序排序的具體要求或降序。阿什比[14,15]和C ebon和Ashby?[16-17]開發(fā)一個計算機化的材料選擇系統(tǒng),稱為劍橋材料選擇器(CMS)的。該系統(tǒng)使用材料的選擇圖表,這是一種顯示,通過優(yōu)化程序使用材料性能數(shù)據(jù)的方法。甄選過程由實施性能指標而定,一個物質(zhì)屬性的組合,而如果最優(yōu)化性能。圖表的開發(fā),以目前的材料,和性能指標,使最合適的材料和形狀可以進行選擇。?
機械設(shè)計
一臺完整機器的設(shè)計是一個復(fù)雜的過程。機械設(shè)計是一項創(chuàng)造性的工作。設(shè)計工程師不僅在工作上要有創(chuàng)造性,還必須在機械制圖、運動學(xué)、工程材料、材料力學(xué)和機械制造工藝學(xué)等方面具有深厚的基礎(chǔ)知識。
任何產(chǎn)品在設(shè)計時第一步就是選擇產(chǎn)品每個部分的構(gòu)成材料。許多的材料被今天的設(shè)計師所使用。對產(chǎn)品的功能,它的外觀、材料的成本、制造的成本作出必要的選擇是十分重要的。對材料的特性必須事先作出仔細的評估。
仔細精確的計算是必要的,以確保設(shè)計的有效性。在任何失敗的情況下,最好知道在最初設(shè)計中有有缺陷的部件。計算(圖紙尺寸)檢查是非常重要的。一個小數(shù)點的位置放錯就可以導(dǎo)致一個本可以完成的項目失敗。設(shè)計工作的各個方面都應(yīng)該檢查和復(fù)查。
計算機是一種工具,它能夠幫助機械設(shè)計師減輕繁瑣的計算,并對現(xiàn)有數(shù)據(jù)提供進一步的分析?;酉到y(tǒng)基于計算機的能力,已經(jīng)使計算機輔助設(shè)計(CAD)和計算機輔助制造(CAM)成為了可能。心理學(xué)家經(jīng)常談?wù)撊绾问谷藗冞m應(yīng)他們所操作的機器。設(shè)計人員的基本職責(zé)是努力使機器來適應(yīng)人們。這并不是一項容易的工作,因為實際上并不存在著一個對所有人來說都是最優(yōu)的操作范圍和操作過程。另一個重要問題,設(shè)計工程師必須能夠同其他有關(guān)人員進行交流和磋商。在開始階段設(shè)計人員必須就初步設(shè)計同管理人員進行交流和磋商,并得到批準。這一般是通過口頭討論,草圖和文字材料進行的。
如前所訴,機械設(shè)計的目的是生產(chǎn)能夠滿足人類需求的產(chǎn)品。發(fā)明、發(fā)現(xiàn)和科技知識本身并不一定能給人類帶來好處,只有當(dāng)它們被應(yīng)用在產(chǎn)品上才能產(chǎn)生效益。因而,應(yīng)該認識到在一個特定的產(chǎn)品進行設(shè)計之前,必須先確定人們是否需要這種產(chǎn)品。
應(yīng)當(dāng)把機械設(shè)計看成是機械設(shè)計人員運用創(chuàng)造性的才能進行產(chǎn)品設(shè)計、系統(tǒng)分析和制定產(chǎn)品的制造工藝學(xué)的一個良機。掌握工程基礎(chǔ)知識要比熟記一些數(shù)據(jù)和公式更為重要。僅僅使用數(shù)據(jù)和公式是不足以在一個好的設(shè)計中做出所需的全部決定的。另一方面,應(yīng)該認真精確的進行所有運算。例如,即使將一個小數(shù)點的位置放錯,也會使正確的設(shè)計變成錯誤的。
一個好的設(shè)計人員應(yīng)該勇于提出新的想法,而且愿意承擔(dān)一定的風(fēng)險,當(dāng)新的方法不適用時,就使用原來的方法。因此,設(shè)計人員必須要有耐心,因為,所花費的時間和努力并不能保證帶來成功。一個全新的設(shè)計,要求屏棄許多陳舊的,為人們所熟知的方法。由于許多人墨守成規(guī),這樣做并不是一件容易的事。一位機械設(shè)計師應(yīng)該不斷地探索改進現(xiàn)有的產(chǎn)品的方法,在此過程中應(yīng)該認真選擇原有的、經(jīng)過驗證的設(shè)計原理,將其與未經(jīng)過驗證的新觀念結(jié)合起來。
新設(shè)計本身會有許多缺陷和未能預(yù)料的問題發(fā)生,只有當(dāng)這些缺陷和問題被解決之后,才能體現(xiàn)出新產(chǎn)品的優(yōu)越性。因此,一個性能優(yōu)越的產(chǎn)品誕生的同時,也伴隨著較高的風(fēng)險。應(yīng)該強調(diào)的是,如果設(shè)計本身不要求采用全新的方法,就沒有必要僅僅為了變革的目的而采用新方法。