畢業(yè)設(shè)計之多媒體工程數(shù)據(jù)庫管理系統(tǒng)方案

1、 畢業(yè)設(shè)計（論文）外文翻譯多媒體工程數(shù)據(jù)庫管理系統(tǒng) Journal of Beijing Institute of Technology,1996,Vol.5,No.1梁允榮 郭貴鎖 宋翰濤 希 高春雷 郭勝（理工大學(xué)計算中心， 100081）摘 要：在以工程數(shù)據(jù)庫為核心的發(fā)動機(jī)CAD系統(tǒng)中，工程數(shù)據(jù)庫管理系統(tǒng)（ECAD-EDBMS）除管理圖形和數(shù)據(jù)外，還能提供文字、聲音、圖像、影像等信息媒體的管理操作功能，為CAD系統(tǒng)中多個子系統(tǒng)開發(fā)和發(fā)動機(jī)設(shè)計者提供多媒體支持環(huán)境，提高工作效率。關(guān)鍵詞：數(shù)據(jù)庫管理系統(tǒng)；多媒體技術(shù)；工程CADMultimedia Engineering Database M

2、anagement SystemLiang Yunrong Guo Guisuo Song Hantao Feng Xi Gao Chunlei Guo Sheng(BIT Computing Center,Beijing Institute of Technology,Beijing 100081)Abstract: In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kemel. ECAD-EDBMS can manage and process th

3、e multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems of ECAD and engine designers. So it improves the design efficiency.Keywords: Database Management Systems; multimedia technology; engineering CAD近年來，多媒體技術(shù)發(fā)展

4、迅速。工程設(shè)計人員可以通過友好用戶界面來有效地管理并處理多媒體。所以計算機(jī)應(yīng)用領(lǐng)域也隨之?dāng)U展。在一些傳統(tǒng)的應(yīng)用領(lǐng)域中，多媒體技術(shù)的應(yīng)用使普通用戶能更容易地掌握計算機(jī)的使用。多媒體技術(shù)已經(jīng)成功地應(yīng)用于許多領(lǐng)域中，如：娛樂產(chǎn)業(yè)，教育業(yè)，廣告業(yè)，培訓(xùn)業(yè)，指揮和咨詢業(yè)等。在CAD工程領(lǐng)域中，多媒體的應(yīng)用是一種新的嘗試，它可以提高CAD系統(tǒng)的應(yīng)用水平和擴(kuò)充作用。如今的機(jī)械設(shè)計師不僅需要有強(qiáng)大的二維和三維圖形的處理能力，而且還需要會綜合管理圖表和非圖表的數(shù)據(jù)。許多研究人員為實(shí)現(xiàn)開發(fā)工程數(shù)據(jù)庫管理系統(tǒng)（EDBMS）這一目標(biāo)盡了很大的努力。EDBMS和EDB將會成為CAD的核心部分。這表示多媒體技術(shù)以全新的面

5、貌應(yīng)用于EDBMS中，將會大大提高EDBMS的功能。我們的研究小組一直致力于EDBMS的CAD應(yīng)用系統(tǒng)發(fā)動機(jī)這一項(xiàng)目（ECAD-EDBMS），ECAD系統(tǒng)需要用到EDBMS的多媒體。在我們不斷發(fā)展的過程中，一些問題已經(jīng)逐步解決了。本文討論的是這種需求和解決辦法。1 ECAD-EDBMS對多媒體的要求（設(shè)計CAD-EDBMS）ECAD應(yīng)用系統(tǒng)包括了大約20個子系統(tǒng)，例如一般設(shè)計的發(fā)動機(jī)（GD），活塞組設(shè)計（PD），汽缸設(shè)計(CD) ，曲軸設(shè)計（CRD）和供油系統(tǒng)（OSD）等等。ECAD是將以太網(wǎng)網(wǎng)絡(luò)連接到工作站和微機(jī)上工作的。ECAD-EDBMS是整個ECAD應(yīng)用系統(tǒng)的核心。那些被EDBMS管理

6、控制的EDBMS和EDB 是上文中所說的CAD子系統(tǒng)之間交換信息的中心。EDBMS應(yīng)具備綜合管理圖表和工程數(shù)據(jù)并從圖表數(shù)據(jù)中提取轉(zhuǎn)化幾何參數(shù)給EDB的能力。ECAD系統(tǒng)中的EDB可分為綜合數(shù)據(jù)庫和局部數(shù)據(jù)庫兩種數(shù)據(jù)庫。例如：在設(shè)計如何將發(fā)動機(jī)投入到GDB中時，要考慮到它的性能參數(shù)，幾何大小和經(jīng)濟(jì)目標(biāo)，因此每個CAD子系統(tǒng)可以從這個GDB中恢復(fù)初始參數(shù)。當(dāng)然，像標(biāo)準(zhǔn)參數(shù)庫（SPPL），包括文字和數(shù)字顯示的技術(shù)參考掃描圖像庫（TRMSIL）的標(biāo)準(zhǔn)部分，圖表生成程序庫（GGPL）的標(biāo)準(zhǔn)部分和材料庫（ML）都屬于GDB。每一個CAD子系統(tǒng)都有其自己的工作EDB和許多包含圖標(biāo)和參數(shù)數(shù)據(jù)庫的代表性產(chǎn)品庫，

7、其多屬于LDB。LDB存儲在本地工作站中并常被CAD子系統(tǒng)應(yīng)用于運(yùn)行這個工作站。這種布置可以提高系統(tǒng)的工作效率。GDB和LDB可以相互傳遞到對方所需要的位置。ECAD-EDBMS提供給綜合多媒體環(huán)境GD,PD,OSD等子系統(tǒng)，如圖1所示，EDBMS應(yīng)滿足以下需要。1.1 綜合管理圖表和工程數(shù)據(jù)的必要條件每個ECAD的CAD子系統(tǒng)需要多種操作管理圖表的功能和能從GDB和LDB方便獲取大量工程數(shù)據(jù)的能力。EDB必須引入大量的工程圖紙和代表性產(chǎn)品的參數(shù)，引擎設(shè)計師也常常需要這些圖紙和參數(shù)。有時候，有些數(shù)據(jù)應(yīng)從圖表提取出并傳遞到GDB或LDB。ECAD-EDBMS是所有CAD子系統(tǒng)的基礎(chǔ)。1.2 對圖

8、像的需求當(dāng)使用標(biāo)準(zhǔn)部分庫和材料庫時，設(shè)計者需要做兩件事情。首先是提取出需要的那部分參數(shù)并將它們轉(zhuǎn)發(fā)給相應(yīng)的圖表生成程序（2D和3D）從而將部分圖表繪制到設(shè)計圖紙上。第二件事就是查找需要的技術(shù)文本，例如技術(shù)指標(biāo)，進(jìn)程說明，包含了大量漢字和圖表的機(jī)械零件圖紙。要深入到這些材料中是非常困難的。以下是關(guān)于標(biāo)準(zhǔn)件和發(fā)動機(jī)的三種技術(shù)材料。(1) 把參數(shù)表放進(jìn)GDB中，再通過設(shè)計者將其恢復(fù)傳遞給圖標(biāo)生成程序。EDBMS必須要為這種參數(shù)表指南創(chuàng)建并管理SPPL。(2) 滿足這種技術(shù)指標(biāo)、進(jìn)程說明和圖紙要求的材料可以通過使用掃描儀以頁碼的形式很容易地投入到TRMSIL中。設(shè)計者可以使用EDBMS逐頁查詢這些圖像

9、檔案。被掃描過的圖像壓縮后能節(jié)省磁盤空間。(3) 關(guān)于整個發(fā)動機(jī)或裝配零部件的產(chǎn)品照片可以用掃描儀掃描或者也可以使用相機(jī)拍照后壓縮文件存入計算機(jī)中。當(dāng)需要決定選擇哪種實(shí)體模型時，設(shè)計者就可以查閱這些圖像文件。1.3 對聲音的要求一些評估會議的錄音記錄、專家談話發(fā)言、有關(guān)設(shè)計經(jīng)驗(yàn)的報告和產(chǎn)品介紹的錄音帶也可以輸入到計算機(jī)磁盤中。這樣設(shè)計者就可以使用這些音頻文件作參考。1.4 對視頻的要求有些視頻文件需要存儲在計算機(jī)磁盤中。這些文檔記錄了運(yùn)行到飽和狀態(tài)的部或外部發(fā)動機(jī)或裝配零部件和汽車引擎裝備在不同路段、坡地的狀況。1.5 對動畫的要求一般的發(fā)動機(jī)設(shè)計需要從不同的角度來設(shè)計規(guī)劃裝配零部件和各種企劃

10、。設(shè)計者希望運(yùn)動系統(tǒng)的動畫具備動作效果。2 ECAD-EDBMS的實(shí)現(xiàn)上述提出的問題有一部分已經(jīng)得到了解決，目前還依然存在的問題需要我們繼續(xù)研究得以改善。我們的發(fā)展環(huán)境是SUN SPARC站運(yùn)行可以提供用二維和三維圖形處理這一強(qiáng)大功能的SUNOS 4.1.1， ORACLE RDBMS和通用機(jī)械CAD系統(tǒng)。SUN系統(tǒng)是一種適用于包括微型計算機(jī)在的以太網(wǎng)網(wǎng)絡(luò)。網(wǎng)絡(luò)軟件是指NFS和PC-NFS。2.1 綜合處理圖表和工程數(shù)據(jù)根據(jù)ORACLE RDBMS和通用機(jī)械CAD系統(tǒng)，我們開發(fā)設(shè)計了ECAD-DEBMS，此ECAD-EDBMS能夠在開放式窗口3.0的環(huán)境下用GUL ECAD-EDBMS的主題連

11、接兩個軟件系統(tǒng)，使其在一個窗口上運(yùn)行。它的菜單條有GDB，LDB，GDB和LDB之間的相互轉(zhuǎn)換，圖表數(shù)據(jù)的提取，SPPL，TRMSIL和ML按鈕。當(dāng)設(shè)計者按動每一個按鈕時,子菜單將會彈出，然后設(shè)計者可以用鼠標(biāo)按鈕從菜單中選擇一項(xiàng)。圖表處理程序在另一個被分為三個子窗口（如：圖表，指令和列表區(qū)域）的窗口工作，這樣設(shè)計者就可以在這個窗口做交互式的設(shè)計。大多數(shù)的設(shè)計工作是在這也圖表窗口完成的。在ECAD-EDBMS的幫助下，設(shè)計者可以按SPPL鍵取回參數(shù)數(shù)據(jù)庫放入一個新的窗口，這樣設(shè)計者就能夠在窗口邊緣使用標(biāo)準(zhǔn)件的數(shù)量和滾動條查找記錄。設(shè)計者可以通過簡便地按下在圖標(biāo)菜單中的圖標(biāo)請求來選擇其中一個需要的

12、記錄并把它保存到中間文件中在將其移到圖像窗口，相應(yīng)的圖表程序用中間文件在圖形窗口的指針位置制作出理想的圖表。當(dāng)然設(shè)計者也可以選擇用TRMSIL菜單選項(xiàng)打開另外一個窗口來逐頁顯示技術(shù)參考材料。標(biāo)準(zhǔn)部分的數(shù)量和上述容是一樣的。工作程序?qū)呙韬玫膱D像文件解壓縮，然后在窗口中顯示出來。設(shè)計者可以根據(jù)說明提示來選擇所需要的那部分參數(shù)。所以用鼠標(biāo)按鈕完成這些窗口的相互交換既方便又快捷。其實(shí)，部分參數(shù)是從ORACLE數(shù)據(jù)庫中取回的，而部分圖表又是又通用CAD系統(tǒng)形成的。但是這一過程對于設(shè)計者來說是透明可見的。所以，ECAD-EDBMS是唯一一種能以同一種方式操作圖表，工程數(shù)據(jù)和掃描圖像的界面工具。ECAD-

13、EDBMS為引擎設(shè)計師提供了極其方便的綜合環(huán)境。2.2 多媒體支持的環(huán)境在工作站上有聲音界面和處理軟件，因此當(dāng)設(shè)計者想要記錄或重新播放這個聲音文件是可以很容易地輸入、輸出聲音信息。有價值的聲音資源都會被搜集起來做好記錄，而且必須重新播放。但是在我們的SUN站上沒有圖像界面，所以我們要用微機(jī)連接上SUN站才能輸入、輸出視頻以與輸入掃描過的標(biāo)準(zhǔn)件。SUN站有一個特殊的子目錄是設(shè)置在PC機(jī)上作為一個邏輯磁盤的（如：G盤），視頻文件名連同一個邏輯磁盤里的文件（所以稱為）一起傳遞給PC機(jī)。顯示程序是同已經(jīng)傳遞的視頻文件名一起開始重新播放的。掃描過的圖像文件的格式必須翻譯成SUN的格式并將其從傳遞到SUN

14、的磁盤上。在SUN站上，掃描后的圖像文件會從每頁500kB壓縮到每頁30kB。所以這成功地解決了多媒體支持環(huán)境的問題。2.3 動畫展示要展示一般布局的發(fā)動機(jī)需要用到很多子系統(tǒng)的繪制結(jié)果，但是要繪制出裝配上活塞，汽缸還有機(jī)軸的運(yùn)轉(zhuǎn)機(jī)理的動畫，就需要借助通用的CAD系統(tǒng)的幫助才能做到。這個動畫是一個仿效運(yùn)動學(xué)的議案。設(shè)計者可以根據(jù)這個議案分析運(yùn)動學(xué)的特征。3 結(jié)束語ECAD-EDBMS正處于發(fā)展進(jìn)步中。它將會把多媒體整合為一個系統(tǒng)并為其他ECAD系統(tǒng)的CAD子系統(tǒng)和引擎設(shè)計師提供擴(kuò)展功能，這樣可以提高設(shè)計的效率。Multimedia Engineering Database Management

15、SystemAbstract : In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kemel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems

16、 of ECAD and engine designers. So it improves the design efficiency.Key words : database management systems; multimedia technology; engineering CADIn recent years, the multimedia technology is developing fast. With the help of friendly user interface, engineering designers can manage and process mul

17、timedia effectively. So computer application fields are extended. In some traditional application fields, multimedia technology has made computers easy to be used by ordinary users.Multimedia are applied successfully in many fields such as entertainment 1, education, advertisement, training, command

18、 and consultative. In the field of engineering CAD, it is a new attempt to apply multimedia to improve the application level and extend the functions of CAD system. Nowadays mechanical designers have not only the need of powerful 2D and 3D graphics processing ability but also the need of integrated

19、management of graphics and nongraphics data. Some researchers have made great efforts to develop engineering database management systems (EDBMS) to attain this goal. EDBMS and EDB will become the kernel of some CAD application systems. It is a new aspect to apply multimedia technology in EDBMS, whic

20、h will greatly enhance the functions of EDBMS. Our research group has been working on the project of EDBMS of the engine CAD application system (ECAD-EDBMS), ECAD system demands multimedia of EDBMS. Some problems have been progressively solved in our developing environment. This paper discusses this

21、 kind of requirements and solutions.1 REQUIREMENTS FOR MULTIMEDIA TO ECAD-EDBMS (ENGINE CAD-EDBMS)The ECAD application system includes about 20 subsystems, for example general design of engine (GD), piston group design (PD), cylinder design (CD), crankshaft design (CRD) and oil supply system (OSD) a

22、nd so on. ECAD will work in an Ethernet network connecting some workstation and microcomputers. ECAD-EDBMS is the kernel of the whole ECAD application system. EDBMS and EDB managed by EDBMS are the centre to exchange information between these CAD subsystems mentioned above. EDBMS should meet the req

23、uirement for integrated management of graphics and engineering data, and have the ability to extract and transfer geometry parameters from graphics data to EDB. EDB of ECAD system can be divided into two kinds of database, global databases (GDB) and local databases (LDB). For example, the performanc

24、e parameters, geometry size and economy targets of the designed engine are put into GDB, so each CAD subsystem can retrieve design parameters from this GDB. Of course the standard parts parameter Lib. (SPPL), technical reference material scanned image Lib. (TRMSIL) of standard parts including text a

25、nd figure shows, graphics generation program Lib. (GGPL) of standard parts, and material Lib. (ML) belong in GDB. Every CAD subsystem has its own working EDB and a lot of typical products Lib. (TPL) including graphics and parameter databases which belong in LDB. LDB is stored in local workstation an

26、d used frequently by local CAD subsystem running on this workstation. This arrangement can improve the systems working efficiency. GDB and LDB can be transferred each other as needed.The ECAD-EDBMS provides the integrated multimedia environment for the GD, PD, OSD subsystem and so on as shown in Fig

27、.1.EDBMS should meet the requirement as follows.1.1 Requirement for Integrated Management of Graphics and Engineering DataEvery CAD subsystem of ECAD needs many functions of graphics operation and management and the ability to access easily a vast amount of engineering data from GDB and LDB. A large

28、 number of engineering drawings and parameters of typical products must be entered into EDB and referenced frequently by engine designers. Sometimes some data should be extracted from graphics and transferred to GDB or LDB. The ECAD-EDBMS is the foundation for all CAD subsystems.1.2 Requirement for

29、ImagesWhen using standard parts Lib. And material Lib. the designer can do two things. The first is to retrieve parameters of desired part and transfer them to corresponding graphics generation program (2D or 3D) to form the part graphics on the designed draw. The second is to look up technical text

30、 about desired part, for example the technical index, processing explanation 2, drawing of mechanical parts contain a vast amount Chinese characters and graphics. To enter these materials is very difficult. There are three kinds of technical materials about standard parts and the engine as following

31、.(1)The parameter tables should be entered into GDB and can be retrieved and transferred to graphics generation programs by designers. EDBMS must create and manage SPPL for this kind of parameter tables of manuals.(2)The materials of technical index and processing explanations and drawings can be si

32、mple put into TRMSIL in the page form using the scanner. Designer can use EDBMS to look up these image files page by page. The scanned images are compressed to save disk space.(3)The product photographs of the whole engine or assembly parts can be scanned with scanners or shooted into computers with

33、 pick up cameras in the compressed files. Designers can look up these image files when making decision of selecting solid model.1.3 Requirements for SoundSome sound records of evaluating meetings and speaks of specialists and statements of design experience and product introduction audio tapes can a

34、lso be input to computer disk. So designers can replay these audio files for reference.1.4 Requirements for videoSome video files are needed to be stored in computer disks. These files record the running saturation of internal or external engines or assembly parts and the vehicle equipped with the e

35、ngines on different roads and sloping fields.1.5 Requirements for AnimationsThe general design of the engine needs the layout of assembly parts and various of the layout from different view point. Designers have the demand for motion animation of movement system 3.2 IMPLEMENTATIONSome problems menti

36、oned above have been solved and remain requirements will be realized. Our development environment is SUN SPARC station running SUNOS 4.1.1, ORACLE RDBMS and universal mechanical CAD system which provides powerful functions in 2D and 3D graphics processing. The SUN system is in an Ethernet network in

37、cluding microcomputers. The network software is NFS and PC-NFS.2.1 Integrated Processing Graphics and Engineering DataBased on ORACLE RDBMS and universal mechanical CAD system, we developed the ECAD-DEBMS which links up these two software systems in the open window 3.0 environment using Motif GUL EC

38、AD-EDBMS runs on one window. It has menu bar with GDB, LDB, transfer between GDB and LDB, extraction of graphics data, SPPL, TRMSIL and ML buttons. When designers press each button the submenus will be pulled out and designers can choose one item from menus with mouse buttons. Graphics processing pr

39、ogram works in another window which is divided into three subwindows (e.g. graphics, command and list area) and designers can make interactive design in this window. Most of design work is done in this graphics window. With the help of ECAD-EDBMS designers can press the SPPL button to retrieve the p

40、arameter databases in a new window, in which designers are able to look up the records using the standard part number and the scroll bars on the window borders. The designer can select one record needed and save it into the medium file and then moves to the graphics window easily to press the icon d

41、esired on the iconsmenu, and the corresponding graphics program uses the medium file to form the desired graphics at the cursor position on the graphics window. Of course designers can open another window by selecting the TRMSIL menu option to display the technical reference material page by page. T

42、he standard part number is the same one mentioned above. The working program decompresses the scanned image files, then displays them in the window. The designer can look at the instruction to select the desired part parameters. So it is easy and fast to exchange between these windows using mouse bu

43、ttons. Actually the part parameters are retrived from ORACLE databases and the part graphics are formed by the universal CAD system. But this process is transparent for the designer. So the ECAD-EDBMS is the only interface to operate graphics, engineering data and the scanned images in the uniform manner. The ECAD-EDBMS provides the extreme convenience and the integrated environment for engine designers.2.2 Environment Supported by the MultimediaOn SUN work station there are the sound interface and processing software, so the sound information can be easi