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AUTONAVI-×××-××××××-××××数字城市3D模型物体外立面纹理采集规范Criterion for facade texture collection of digital city 3Dmodel2010-XX-XX发布 2010-XX-XX实施v1.0 可编辑可修改目次前言 (I)1范围 (1)2术语及定义 (1)3采集要求 (1)3.1阅读索引 (1)3.2采集时间 (1)3.3数据格式 (2)3.4透视角度 (2)3.5环境对色调影响 (2)3.6采集记录 (2)3.7文件目录编写 (3)3.8起始点标注 (3)3.9采集原则 (3)3.10采集安全 (3)采集准备 (3)4采集方法 (3)4.1建筑物全景采集 (4)4.2建筑物特征采集 (4)4.3小场景全貌采集 (5)4.3.1小场景鸟瞰图采集（条件允许时采集） (5)4.3.2小场景鸟瞰图相对位置与特征采集（条件允许时采集） (6)4.4小场景无鸟瞰图采集 (7)4.5棚户区的采集 (8)采集的基本原则前言本规范适用于2010年3月1日后采集的数字城市3D模型物体外立面纹理数据；若随后的数据内容或功能不发生任何变化，本规范仍适用于其后采集的3D模型物体外立面纹理数据。
本规范版本号为。
本规范由高德集团武汉分公司三维数字城市外业部提出。
本规范由高德集团数据标准委员会归口。
本规范起草部门：高德集团武汉分公司三维数字城市外业部。
本规范主要起草人：郭累、陈前龙。
内部资料不得翻印IIIv1.0 可编辑可修改数字城市3D模型物体外立面纹理采集规范1范围本规范规定了数字城市3D模型物体外立面纹理采集要求、采集内容、详细采集步骤、数据格式和数据成果提交。
本规范适用于数字城市3D模型物体外立面纹理采集作业。
2术语及定义2.1全景 panorama对某一物体进行全貌描述。
137学研探索产品前言回族是我国重要的少数民族之一，几乎分布在全国各个省份。
回族历史可以追溯到公元651年的唐代，波斯和阿拉伯商人通过海路来到中国，传入伊斯兰教。
随后与汉族、蒙古族、维吾尔族等民族融合形成了统一的民族。
回族文化主体是伊斯兰文化，但是经过长期的与中华传统文化相互交融后，形成了有中华文化特色的伊斯兰文化。
纹样是中国传统文化表现的重要的途径[1-4] ，回族传统纹样的装饰艺术受伊斯兰教信仰的影响形成了植物纹样、文字纹样、几何纹样三种装饰纹样，其中几何纹样是最基本的也是重要的装饰纹样[5-8] 。
2019年8月习近平总书记在敦煌研究院与文保专家座谈时强调要加强对我国优秀民族文化的保护，显然对回族传统几何纹样的研究和创新设计符合国家的号召。
一、回族传统几何纹样的内涵及构成回族传统文化基于伊斯兰传统文化，长时间地融合中国传统文化后产生的中国独有的伊斯兰文化，其传统几何装饰纹样经过了长期的演变和发展，呈现出别具一格的艺术风格以及民族韵味，以其浓郁的宗教色彩和民族特色，在世界艺术之林中享有重要的地位。
伊斯兰教是世界上三大宗教之一，核心教义是“绝对唯一的神”，教徒穆斯林信奉的真主安拉是唯一的神。
正是因为“真主唯一”的独特思想，公共场合表面装饰中禁止出现人物动物等形象，这一规定促进了回族几何纹样的发展，形成了回族装饰独有的视觉特色。
匠人借助直尺、圆规绘出各式各样的几何形状将一个平面进行完美分割，使画面形成复杂又和谐的画面；几何纹样完美的阐述了伊斯兰无限、真主唯一的思想，具有浓烈的宗教色彩。
圆是最能体现伊斯兰“真主唯一”思想的几何图案，很多回族传统装饰纹样都是由这一基本图案演变而来的，体现了真主是万物之源的思想。
圆形装饰广泛应用在建筑的顶棚及大厅的吊灯等。
《古兰经》记载，“你当多多的纪念你的主，你应当朝夕赞他超绝”。
回族几何纹样艺术是一种繁复艺术，这种几何纹样看似没有根据、复杂多变，但是都能通过1-3种多边（角）形进行排列、组合、旋转、覆盖、延续、填充等方法得到。
text-to-3d with classifier score distillation 概述说明1. 引言1.1 概述本文旨在介绍"text-to-3d with classifier score distillation"的概念和应用。
"text-to-3d"是一种技术，可以将文本信息转换为三维场景或模型，通过深度学习算法实现。
而"classifier score distillation"则是一种方法，用于提取分类器的得分信息并进行蒸馏处理。
本文将详细介绍这两个技术及其原理、应用领域和实现方法。
1.2 文章结构本文共分为五个部分：引言、正文、text-to-3d、classifier score distillation 和结论。
在正文部分，将详细介绍"text-to-3d"技术的原理、应用领域和实现方法；而在"classifier score distillation"部分，则会针对分类器得分蒸馏的相关内容进行阐述。
最后，在结论中总结主要发现，并探讨研究意义及未来展望。
1.3 目的本文的目的是通过对"text-to-3d with classifier score distillation"这一技术的全面介绍，使读者对这一领域有一个清晰的认识和了解。
同时，希望能够展示该技术在不同领域中的潜在应用价值，并为相关研究提供启示和指导。
通过本文的阐述，读者将能够掌握"text-to-3d"技术的原理、实现以及与"classifier score distillation"相结合的应用方法，为进一步研究和开展相关工作提供基础和支持。
这样便清晰地描述了“1. 引言”部分的内容。
2. 正文在本文中，我们将介绍text-to-3d技术和classifier score distillation方法，并探讨它们的原理、应用领域以及实现方法。
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A l l r i g h t s r e s e r v e d . 3D E X P E R I E N C E ®, t h e C o m p a s s i c o n , t h e 3D S l o g o , C A T I A , S O L I D W O R K S , E N O V I A , D E L M I A , S I M U L I A , G E O V I A , E X A L E A D , 3D V I A , B I O V I A , N E T V I B E S , I F W E a n d 3D E X C I T E a r e c o m m e r c i a l t r a d e m a r k s o r r e g i s t e r e d t r a d e m a r k s o f D a s s a u l t S y s t èm e s , a F r e n c h “s o c i ét é e u r o p ée n n e ” (V e r s a i l l e s C o m m e r c i a l R e g i s t e r # B 322 306 440), o r i t s s u b s i d i a r i e s i n t h e U n i t e d S t a t e s a n d /o r o t h e r c o u n t r i e s . A l l o t h e r t r a d e m a r k s a r e o w n e d b y t h e i r r e s p e c t i v e o w n e r s . U s e o f a n y D a s s a u l t S y s t èm e s o r i t s s u b s i d i a r i e s t r a d e m a r k s i s s u b j e c t t o t h e i r e x p r e s s w r i t t e n a p p r o v a l .Our 3D EXPERIENCE® platform powers our brand applications, serving 11 industries, and provides a rich portfolio of industry solution experiences.Dassault Systèmes, the 3D EXPERIENCE Company, is a catalyst for human progress. We provide business and people with collaborative virtual environments to imagine sustainable innovations. By creating ‘virtual experience twins’ of the real world with our 3D EXPERIENCE platform and applications, our customers push the boundaries of innovation, learning and production.Dassault Systèmes’ 20,000 employees are bringing value to more than 270,000 customers of all sizes, in all industries, in more than 140 countries. For more information, visit .Europe/Middle East/Africa Dassault Systèmes10, rue Marcel Dassault CS 4050178946 Vélizy-Villacoublay Cedex FranceAmericasDassault Systèmes 175 Wyman StreetWaltham, Massachusetts 02451-1223USAAsia-PacificDassault Systèmes K.K.ThinkPark Tower2-1-1 Osaki, Shinagawa-ku,Tokyo 141-6020JapanBatch UploadBenefitsSpeed up onboarding and deployment by easilymigrating batch drawings to the 3D EXPERIENCE platform.• Simplify data migration with batch uploads of drawings to the 3D EXPERIENCE platform and detection of duplicate files.5。
三维模型轮廓线抽取算法
吴亚东;刘玉树
【期刊名称】《中国图象图形学报》
【年(卷),期】2001(006)002
【摘要】虽然三维模型的轮廓线在图形交流中起着重要的作用，但由于轮廓线是视点依赖的，当物体在空间运动时，用现有算法从复杂的三维模型中抽取轮廓线需耗费大量时间，为了提高抽取轮廓线的速度，提出了两种新的抽取三维模型轮廓线算法.这两种算法是先利用轮廓线的局部极值特性来获得部分轮廓边，然后利用轮廓线的连通性，通过简单的比较运算，即可获得三维模型的外部轮廓线.实验结果表明，该两种算法都可快速获得三维模型的外围轮廓线，最后还将本算法与相关算法进行了详细的比较分析.
【总页数】4页(P191-194)
【作者】吴亚东;刘玉树
【作者单位】北京理工大学计算机科学工程系,;北京理工大学计算机科学工程系,【正文语种】中文
【中图分类】TP391
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CATIA全模块介绍(最新版本CATIA V5R17)作者：TomLee关键词：CATIA,CATIA V5,CATIA V4,CATIA V5R17来源：无维网（）CATIA是英文 Computer Aided Tri-Dimensional Interface Application 的缩写。
是世界上一种主流的CAD/CAE/CAM 一体化软件。
在70年代Dassault Aviation 成为了第一个用户，CATIA 也应运而生。
从1982年到1988年，CATIA 相继发布了1版本、2版本、3版本，并于1993年发布了功能强大的4版本，现在的CATIA 软件分为V4版本和 V5版本两个系列。
V4版本应用于UNIX 平台，V5版本应用于UNIX和Windows 两种平台。
V5版本的开发开始于1994年。
为了使软件能够易学易用，Dassault System 于94年开始重新开发全新的CATIA V5版本，新的V5版本界面更加友好，功能也日趋强大，并且开创了CAD/CAE/CAM 软件的一种全新风格。
法国 Dassault Aviation 是世界著名的航空航天企业。
其产品以幻影2000和阵风战斗机最为著名。
CATIA的产品开发商Dassault System 成立于1981年。
而如今其在CAD/CAE/CAM 以及PDM 领域内的领导地位，已得到世界范围内的承认。
其销售利润从最开始的一百万美圆增长到现在的近二十亿美圆。
雇员人数由20人发展到2，000多人。
CATIA是法国Dassault System公司的CAD/CAE/CAM一体化软件，居世界CAD/CAE/CAM领域的领导地位，广泛应用于航空航天、汽车制造、造船、机械制造、电子\电器、消费品行业，它的集成解决方案覆盖所有的产品设计与制造领域，其特有的DMU电子样机模块功能及混合建模技术更是推动着企业竞争力和生产力的提高。
CATIA 提供方便的解决方案，迎合所有工业领域的大、中、小型企业需要。
ES123735Advanced Anxiety-Free Isometric Configuration in AutoCAD Plant 3DKenneth Fauver Autodesk, IncDescriptionThis class will cover the proper methods for customizing AutoCAD Plant 3D 2018 isometric styles using the user interface within Project Setup, supplemented with XML file editing.Attendees will learn when to use the user interface, as well as gain insight into the advanced customization available by directly editing the IsoConfig.xml file for the style. Topics covered will include understanding how filters are used in the isometric configuration. We’ll learn the difference between themes, schemes, memes—and how to manipulate annotations and dimensions to get the desired isometric deliverable.SpeakerKen Fauver has been employed by Autodesk for the past 6 years. He is part of the CS WW Project Delivery AMER as a Plant 3D and P&ID Implementation Consultant. Previously part of the ENI & TS-AMER Technical Sales Specialist Team. Concentrating on activities related to Plant 3D. Ken supports the North American AEC Named Accounts working with Owner /Operators and other Key Accounts. Has over 25 years’ experience in the Oil and Gas industry as a Piping Designer, Drafter, and CAD Administrator. Prior to joining Autodesk, Ken worked for several companies in the Petro/Chemical markets including Wink Engineering, ACPlant dbaFlow Logic International and Jacobs Engineering. My work-related interests include pipe design, software support and training. Also, worked as a System Administrator, AutoCAD Programmer, Trainer and CAD Coordinator with several software applications during his pre-Autodesk career.Learning ObjectivesLearn how to customize an isometric style using Project Setup in AutoCAD Plant 3D Learn how to do specific advanced customization directly in the IsoConfig.xml file Understand the different parts and syntax of the IsoConfig.xml fileLearn how to create an isometric style template for future useTable of ContentsIntroduction (4)Isometric Drawing Setup (5)Symbols and Reference (5)Edit Isometric Symbols (6)Isometric Symbols (SKEY) (6)Isosymbolstyles.dwg (6)Isokeyacadblockmap.xml (6)Iso Style Setup (7)Content paths (7)Production iso output directory: (7)Quick iso output directory: (8)Iso Style Default Settings (8)Annotations (10)Iso sheet continuation (to) (11)Iso sheet continuation (from) (11)Other connected pipe lines (12)Connected equipment nozzles (12)Drain Annotation (13)Vent Annotation (13)Open pipe ends (14)Closed pipe ends (14)Connection text: (15)Dimensions (17)Themes (18)Default Theme (18)Fitting To Fitting Theme (19)Small Bore Piping Theme (20)Vent/Drain Piping Theme (21)Offline Instrument Connection Theme (22)Existing Piping Theme (23)Continuation/Connection Piping Theme (24)Sloped and Offset Piping (25)Title Block and Display (26)Table Setup (28)Iso Themes (30)Title Block Attributes (32)IsoConfig.xml (36)Autodesk Iso Style Editor Public Beta (36)What is the isoconfig.xml (37)Modifying the IsoConfig XML (38)Themes (38)Split (41)Filters (41)Miscellaneous Annotation Changes (42)Appendix (47)References: (49)Previous AU Classes (49)IntroductionThis class will focus on an isometric style that I configured for a customer in the Petro/Chem industry. These setting are common to most industries and will serve as a starting place for those of you that are new to configuring Plant 3D isometric.Isometric Drawing SetupThis section describes the settings used to setup the AU_Final_ANSI-C Isometric Style. Note: This isometric style can be used for future projects by updating the isometric title block for each customer.Symbols and ReferenceThis section will allow you to modify SKEY and Annotation symbols.Figure 1Changes made in the Symbols and Reference dialog will get written to the IsoSymbolStyles .dwg and Plant3dIsoSymbols.dwg drawing files.Visit the ? help documentation.Edit Isometric SymbolsCreated these new isometric symbol blocks.Isometric Symbols make use of AutoCAD Blocks along with the use of Dynamic Block parameter.For AutoCAD Isometric to recognize this new symbol we need to new SKEY definitions in the IsoSkeyAcadBlockMap.xml file as shown below.Isometric Symbols (SKEY)Isosymbolstyles.dwgInserted ExtBodyGateValve block.Isokeyacadblockmap.xmlAdded line item to Valves section<!-- Begin: Valves --><SkeyMap SKEY = "V3??" AcadBlock ="3WayValve"/><SkeyMap SKEY = "V4??" AcadBlock ="4WayValve"/><SkeyMap SKEY = "AR??" AcadBlock ="ValveAngle"/>………<SkeyMap SKEY = "VE??" AcadBlock ="ExtBodyGateValve"/> <!-- End: Valves -->Iso Style SetupFigure 2The Iso Style that was modified for this class is called AU_Final_ANSI-C. Except for Content paths all other settings in this dialog are set to their default values.Content pathsThe AU_Final_ANSI-C isometric style resides under the following folder:“C:\Plant 3D 2017 Projects\2017 Projects\AU 2017 Project\Isometric”Production iso output directory:Location where the Production Isometrics are created.“C:\Plant 3D 2017 Projects\2017 Projects\AU 2017Project\Isometric\AU_Final_ANSI-C\ProdIsos\”Quick iso output directory:Location where the Quick Isometrics are created.“C:\Plant 3D 2017 Projects\2017 Projects\AU 2017Project\Isometric\AU_Final_ANSI-C\QuickIsos\”View the ? help documentation.Iso Style Default SettingsWhen creating isometrics, you have option to change some settings at run time by selecting the Advanced… button.Figure 3View the ? help documentation.Or set these values as default through the Iso Style Defaults Settings in Project Setup.Figure 4The only setting that were changed are as follows:Turn on Overwrite existing filesLevel of congestion to split isometric at: Set to MoreTurn off Export data tablesVisit the ? help documentation.AnnotationsFigure 5In the Annotations dialog the following settings have been changed: Spool, Welds, and Cut pieces annotation has been turned off. Enclosure height and text have been set to 0.09375.Iso sheet continuation (to)Removed (#) from the connection prefix.Figure 6 Iso sheet continuation (from)Removed (#) from the connection prefix.Figure 7Other connected pipe linesAdded (DWG) to the connection prefix.Figure 8 Connected equipment nozzlesNo change to Connected equipment nozzles. .Figure 9Drain AnnotationDisable the display of coordinates for drain annotation.Figure 10Vent AnnotationDisable the display of coordinates for vent annotation.Figure 11Open pipe endsNo change.Figure 12Closed pipe endsDisabled the display of closed pipe annotation and coordinates.Figure 13Connection text:The Connection text box allows you to change the information shown on the isometric continuation.For Example:Out-of-the-box the continuation for a pipeline connected to equipment with look like thisUnder the Connection and continuations > Connected equipment nozzle > Connection text: add the following:<Equipment.Tag>, <Nozzle.Tag>, <Nozzle.Size>-<Nozzle.PressureClass>LB$<Equipment.PartSizeLongDesc>Note: The “$” in the text represents typing the “Enter” key to start a new text line.Results:Visit the ? help documentation.DimensionsSets the format for dimensions placed in isometric drawings.Figure 14 Changed the following settings:Dimension text height: 0.0830Do not over constrain string dimensions is checked. Visit the ? help documentation.ThemesSpecifies dimension, annotation, and isometric symbol scale for piping and override themes.Default ThemeThe default theme specifies isometric options for normal piping.Figure 15Fitting To Fitting ThemeThe Fitting to Fitting theme specifies isometric options for fittings that are connected. Overrides the Default Theme.Figure 16Small Bore Piping ThemeThe Small-Bore Piping theme specifies isometric options for small borefittings and pipe as defined in the Dimension section above. Overrides the Default Theme.Figure 17In this case all pipe and fitting 2” and below are considered Small Bore Piping.Vent/Drain Piping ThemeThe Vent/Drain Piping theme specifies isometric options for Vent andDrain piping. Overrides the Default Theme.The may be some additional configuration changes in the IsoConfig.xml to get exactly what you want he. Usually must do with modifying orcreating filters. We will discuss this later in this document.Figure 18Offline Instrument Connection ThemeThe Offline Instrument Connection theme specifies isometric options for offline instruments. Overrides the Default Theme. Currently set to not dimension instruments.Figure 19Existing Piping ThemeThe Existing Piping theme specifies isometric options for existing pipe and fittings. Overrides the Default Theme. Currently set to not to show dimensions or annotations.Figure 20Continuation/Connection Piping ThemeThe Continuation/Connection Piping theme specifies isometric options forcontinuations and/or connections. Overrides the Default Theme. Currently set to not to show annotations only.Figure 21Visit the ? help documentation.Sloped and Offset PipingSpecifies formatting for sloped lines, including falls, 2D offsets, and 3D offsets.Figure 22Visit the ? help documentation.Title Block and DisplaySets up the title block for isometric drawings.Figure 23Selecting the Setup Title Block… button will allow you to modify the isometric title block you would like to use for your project.Title Block InsertionTo change out the title block with your custom title block, follow these steps:1. Insert your title block drawing into the isometric template.2. Erase the existing Title Block reference.3. Purge the Title Block block definition.4. Use the RENAME command to change your company title block name to “TitleBlock”.Here we eliminate the tables for Cut Pieces and Welds.Figure 24 Visit the ? help documentation.Table SetupBOM Table LayoutThis dialog configures the columns and column layout to be used for the Bill of Material (BOM). Use default values.Figure 25Visit the ? help documentation.BOM Table SettingsSpecifies the bill of materials settings. Use default values.Figure 26Visit the ? help documentation.Iso ThemesIso Themes are used to control which Dimension Style, Multileader Style, Table Style, Text Style, and Layer Setup.Default ThemeFigure 27Override ThemesYou can override the default layers for each them. No changes here.Visit the ? help documentation.Figure 28No changes were made to the Override Themes.Visit the ? help documentation.Title Block AttributesAutomatically fill out the title block from a data source.Map Title Block AttributesThe isometric configuration allows for two ways to map data to the title block attributes. You can either map directly to the database properties or you use an external spreadsheet referred to a Line Designation Table (LDT).Selecting the Map attributes… button will take you to the dialog that allows you to map directly to the database properties.For the AU_Final_ANSI-C Iso Style my customer opted for the Line DesignationTable method. Clicking on the LDT Setup tab in the dialog starts thisconfiguration.LDT file (XLS): <drive>\<project root>\Isometric\AU_Final_ANSI-C\Line List for Isos.xlsWorksheet name: LNLIST (Tab inside the XLS to be used)Header row: 1 (Row number that in considered the header. The spreadsheet can only have one header row.)Line number column: Line# (Name of column containing the Line Number)View LDT… (Is everything is correct, this button will show a preview of the spreadsheet data)Figure 29Map Title Block Attributes (Cont’d)Selecting the View LDT… button will show the columns of data in thespreadsheet.Figure 30The columns will now be accessible in the attribute map dialog. Set them as shown. Notice I have utilized a combination of database properties and LDT columns.Figure 31Finished title block with all attributes assigned.Figure 32 Visit the ? help documentation.IsoConfig.xmlSome isometric configuration requires modification of the IsoConfig.xml file. Meaning there was not a setting in the user interface to change or I needed to tweak the setting further to get the results needed.I will outline those changes in this section.Autodesk Iso Style Editor Public BetaHello Plant 3D Beta forum participants,I'm pleased to announce that we have just made available the Autodesk Iso Style Editor Public Beta to you for testing!We know how difficult it is having to navigate and work with the Iso Config XML file when tweaking the finer details of Iso Styles, so the team has put together the Iso Style Editor to try and simplify things for you.You can work with a Properties table UI, and still have access to the XML when you need it! Go to the DOWNLOADS page to watch our getting started video, check out the PDF guide, and download the Iso Style Editor!Next, let us know your thoughts! The FORUM for the Iso Style Editor is here.Have a friend that isn't part of the forum yet? Send them this invite link:https://goo.gl/AoSxBGWhat is the isoconfig.xmlXml stands for eXtensible Markup Language. Although called, a language, it’s better to think of xml as a way of organizing information for developers. Xml is closer to customizable database format than a programming language. For further information on using XML please read: /xml/xml_whatis.aspInformation within xml is grouped within tags by including sub-tags, and/or attributes. The contents and types of tags are completely definable by the developer. The xml follows a loose structure dictated here: /xml/xml_tree.asp.In short, xml is organized in a tree hierarchy with elements indicated by brackets. Applying the structure to the isoconfig.xml, our root element is the element IsoconfigDefinition.Xml definitions:<Tag> – a value surrounded in brackets. Same for Parent and Child elements.<Tag/>– an element (tag) is closed with a slash “/”. Same for Parent and Child elements. Attributes – A property of a tag residing within its brackets, i.e. <Tag IsLinear=”true”/>. The IsLinear value is an attribute that has a true or false value.Comments – Comments are surrounded with <!-- and closed with !-->.Modifying the IsoConfig XMLThemesA theme is a named configuration for Dimensions, Annotations, Bend, Elbow,Symbols, and Insulation.Default ThemeDefault dimension format cutoff. All dimension 12” and above are shownas feet and inches instead of 24 and above.Formatting of the line number annotation. This example changes the format to <Line#>-<Size>-<Spec>Fitting To Fitting ThemeFitting to fitting dimension format cutoff. All dimension 12” and above areshown as feet and inches instead of 24 and above.Small Bore Piping ThemeTo turn off the dimensioning of plugs for small bore piping “Overall”.To turn off the dimensioning of plugs for small bore piping “String”.SplitThe split section controls how the isometric engine will break up the model into drawingsTo change the number of components shown as dashed for the continuation. Also includes flanges.FiltersAdded new filters for changes made to Small Bore Piping Theme above.Eliminate insulation break symbol at iso message.Miscellaneous Annotation ChangesPrevent the valve text from being grouped with other annotations and have the leader stop at center of BOM tag.Default Theme > Annotations > AnnotationSchemesSeparate the annotation from the BOM tag.Default Theme > Annotations > AnnotationSchemesResolve the issue of valves with different descriptions being grouped into one row in the BOM.Resolve the issue of pipe supports with different descriptions being grouped into one row in the BOM.Resolves the issue of pipe being separated into two rows with identical descriptions and sizes in the BOM.Resolves the issue of valves with different descriptions being grouped into one row in the BOM.To enable inline instruments to be listed in Iso BOM add the following.The SizeDelimiter can be made lower case.Also, within the Data section, the Index on an AggregatedList may include a character attribute which includes characters that are allowed as the index.AppendixVariable Filter Values (including but not limited to the following):Type– all components. Example: "Type = 'Bend'"DIRECTION– for valve operators. Example: “DIRECTION='E'"UNDIMENSIONED – Boolean property of an isometric messageEND1, END2– end conditions. Example: FL, BW, SC, SW, CP, etc.SHORTRADIUS – short radius elbow flag. Valid value: SRService – service property for a componentCategory – shop or field items. Valid values: ERECTION-ITEM, FABRICATION-ITEM, OFFSHORE-ITEMSymbolName – connector symbol. Example: FieldWeldLength – Pipe lengthFieldItem– flag for field itemsExisting – flag for existing itemsITEM-CODE – ITEM-CODE property from the piping spec or catalogConnectionSize – size of a component end connection in decimal unitsSpoolNumber – spool number property for a component[FLAT-DIRECTION]– for eccentric reducers[TRACING-SPEC]– tracing spec property for a component[REFERENCE-TO] for continuations[REFERENCE-FROM] – for continuations[ANGLE-CDEG] – cutback elbow degreesTEXT– for messagesMPVLEVEL– for multiport valvesMaxPipeLength– for fixed length pipeSKEY – Isometric symbol SKEYValid Operators:LIKE– contains a string and is usually used with a wildcard. Example: "Type LIKE 'TEE*'"=- exactly matches. Example: "Type='Support'"NOT - inverts the operation. Example: "NOT [ITEM-CODE] IS NULL" means that when the value for ITEM-CODE is not NULL (blank).OR– one condition or another. Best if enclosed with parentheses. Example: "Type='FLANGE-BLIND' OR Type='CAP'"AND– one condition as well as another. Best if enclosed with parentheses. Example: "Type LIKE '*Weld' AND Category='FABRICATION-ITEM'"()– for grouping logical conditions. Example: "Type = 'olet' AND (SKEY='LASC' ORSKEY='LASW' OR SKEY='LABW')"‘– for enclosing literal text. Example: "Type = 'END-CONNECTION-PIPELINE'"* - wildcard. Example: "Type LIKE '*Weld'”<- less than “<” symbol. Example: (ConnectionSize > 0 AND ConnectionSize <= 2) means “ConnectionSize is greater than 0 but less than 2”.>– greater than “>” symbol. Example usage: “<>” is the same as “not equal to”References:Autodesk Knowledge NetworkAutoCAD Plant 3D 2018 HelpDe-Mystifying AutoCAD Plant 3D Isometrics Configuration ReferenceMicrosoft Developer NetworkPrevious AU Classes(AU2015) ES10519-L: Customize Your AutoCAD Plant 3D Isometric Configuration - Mike Musgrave(AU2014) PD6442-L: Configuring AutoCAD Plant 3D Isometrics - Bernd Gerstenberger (AU 2013) PD1392: Setting up Isometrics in AutoCAD Plant 3D - Carsten Beinecke。
3d MAX 菜单中英文对照表Absolute Mode Transform Type-in绝对坐标方式变换输入Absolute/Relative Snap Toggle Mode绝对/相对捕捉开关模式ACIS Options ACIS选项Activate活动;激活Activate All Maps激活所有贴图Activate Grid激活栅格；激活网格Activate Grid Object激活网格对象；激活网格物体Activate Home Grid激活主栅格;激活主网格ActiveShade实时渲染视图；着色；自动着色ActiveShade(Scanline）着色(扫描线）ActiveShade Floater自动着色面板;交互渲染浮动窗口ActiveShade Viewport自动着色视图Adaptive适配;自动适配；自适应Adaptive Cubic立方适配Adaptive Degradation自动降级Adaptive Degradation Toggle降级显示开关Adaptive Linear线性适配Adaptive Path自适应路径Adaptive Path Steps适配路径步幅；路径步幅自动适配Adaptive Perspective Grid Toggle适配透视网格开关Add as Proxy加为替身Add Cross Section增加交叉选择Adopt the File’s Unit Scale采用文件单位尺度Advanced Surface Approx高级表面近似；高级表面精度控制Advanced Surface Approximation高级表面近似；高级表面精度控制Adv。
Lighting高级照明Affect Diffuse Toggle影响漫反射开关Affect Neighbors影响相邻Affect Region影响区域Affect Region Modifier影响区域编辑器；影响区域修改器Affect Specular Toggle影响镜面反射开关AI Export输出Adobe Illustrator(＊.AI)文件AI Import输入Adobe Illustrator(＊.AI）文件Align对齐Align Camera对齐摄像机Align Grid to View对齐网格到视图Align Normals对齐法线Align Orientation对齐方向Align Position对齐位置(相对当前坐标系）Align Selection对齐选择Align to Cursor对齐到指针Allow Dual Plane Support允许双面支持All Class ID全部类别All Commands所有命令All Edge Midpoints全部边界中点;所有边界中心All Face Centers全部三角面中心;所有面中心All Faces所有面All Keys全部关键帧All Tangents全部切线All Transform Keys全部变换关键帧Along Edges沿边缘Along V ertex Normals沿顶点法线Along Visible Edges沿可见的边Alphabetical按字母顺序Always总是www_bitscn_com中国.网管联盟Ambient阴影色；环境反射光Ambient Only只是环境光；阴影区Ambient Only Toggle只是环境光标记American Elm美国榆树Amount数量Amplitude振幅;幅度Analyze World分析世界Anchor锚Angle角度;角度值Angle Snap Toggle角度捕捉开关Animate动画Animated动画Animated Camera/Light Settings摄像机/灯光动画设置Animated Mesh动画网格Animated Object动画物体Animated Objects运动物体;动画物体；动画对象Animated Tracks动画轨迹Animated Tracks Only仅动画轨迹Animation动画Animation Mode Toggle动画模式开关Animation Offset动画偏移Animation Offset Keying动画偏移关键帧Animation Tools动画工具Appearance Preferences外观选项Apply Atmospherics指定大气Apply—Ease Curve指定减缓曲线Apply Inverse Kinematics指定反向运动Apply Mapping指定贴图坐标Apply—Multiplier Curve指定增强曲线Apply To指定到；应用到Apply to All Duplicates指定到全部复本Arc弧；圆弧Arc Rotate弧形旋转;旋转视图；圆形旋转Arc Rotate Selected弧形旋转于所有物体;圆形旋转选择物；选择对象的中心旋转视图Arc Rotate SubObject弧形旋转于次物体；选择次对象的中心旋转视图Arc ShapeArc Subdivision弧细分；圆弧细分Archive文件归档Area区域Array阵列Array Dimensions阵列尺寸;阵列维数Array Transformation阵列变换ASCII Export输出ASCII文件Aspect Ratio纵横比Asset Browser资源浏览器Assign指定Assign Controller分配控制器Assign Float Controller分配浮动控制器Assign Position Controller赋予控制器Assign Random Colors随机指定颜色Assigned Controllers指定控制器At All Vertices在所有的顶点上At Distinct Points在特殊的点上At Face Centers 在面的中心At Point在点上Atmosphere氛围；大气层；大气，空气;环境Atmospheres氛围Attach连接;结合；附加Attach Modifier结合修改器Attach Multiple多项结合控制;多重连接Attach To连接到Attach To RigidBody Modifier连接到刚性体编辑器Attachment连接；附件Attachment Constraint连接约束Attenuation衰减AudioClip音频剪切板AudioFloat浮动音频Audio Position Controller音频位置控制器AudioPosition音频位置Audio Rotation Controller音频旋转控制器AudioRotation音频旋转Audio Scale Controller音频缩放控制器AudioScale音频缩放；声音缩放Auto自动Auto Align Curve Starts自动对齐曲线起始节点Auto Arrange自动排列Auto Arrange Graph Nodes自动排列节点Auto Expand自动扩展Auto Expand Base Objects自动扩展基本物体Auto Expand Children自动扩展子级Auto Expand Materials自动扩展材质Auto Expand Modifiers自动扩展修改器Auto Expand Selected Only自动扩展仅选择的Auto Expand Transforms自动扩展变换Auto Expand XYZ Components自动扩展坐标组成Auto Key自动关键帧Auto-Rename Merged Material自动重命名合并材质Auto Scroll自动滚屏Auto Select自动选择Auto Select Animated自动选择动画Auto Select Position自动选择位置bitsCN#com中国网管联盟Auto Select Rotation自动选择旋转Auto Select Scale自动选择缩放Auto Select XYZ Components自动选择坐标组成Auto—Smooth自动光滑AutoGrid自动网格；自动栅格AutoKey Mode Toggle自动关键帧模式开关Automatic自动Automatic Coarseness自动粗糙Automatic Intensity Calculation自动亮度计算Automatic Reinitialization自动重新载入Automatic Reparam.自动重新参数化Automatic Reparamerization自动重新参数化Automatic Update自动更新Axis轴;轴向;坐标轴Axis Constraints轴向约束Axis Scaling轴向比率Back后视图Back Length后面长度Back Segs后面片段数Back View背视图Back Width后面宽度Backface Cull背面忽略显示；背面除去;背景拣出Backface Cull Toggle背景拣出开关Background背景Background Display Toggle背景显示开关Background Image背景图像Background Lock Toggle背景锁定开关Background Texture Size背景纹理尺寸；背景纹理大小Backgrounds背景Backside ID内表面材质号Backup Time One Unit每单位备份时间Banking倾斜Banyan榕树Banyan tree榕树Base基本；基部；基点；基本色；基色Base/Apex基点/顶点Base Color基准颜色；基本颜色Base Colors基准颜色Base Curve基本曲线Base Elev基准海拔；基本海拔Base Objects导入基于对象的参数，例如半径、高度和线段的数目;基本物体Base Scale基本比率Base Surface基本表面;基础表面Base To Pivot中心点在底部Bevel Profile轮廓倒角Bevel Profile Modifier轮廓倒角编辑器;轮廓倒角修改器Bezier贝塞尔曲线Bezier Color贝塞尔颜色bbs。
Inventor目前最全的37个插件软件名称说明网站3G author design analysis, validation, andoptimization of designs created inAutodesk Inventor, Solid Edge,Pro/Engineer, Widlfire, SolidWorks,CATIA, XXen and others (reviews)/Products.htmlACAD Stahl Inventor provides ability to create skeleton steelconstruction in Autodesk Inventor, bySchäfer Computer GmbH (German)http://www.proficad.de/acadstahli.htmALGOR InCAD Designer analysis and simulation performed onAutodesk Inventor and MechanicalDesktop geometry/products/InCADD1505/AutoPOL Unfolder sheet metal unfolder, handles simplemodels with elements like regularbends and complicated free-formmodels, by FCC Software AB/CFD-CADalyzer fluid flow mesh generation and analysisoperates directly on native Inventorgeometry, by ESI Group/cad_overview.php?cad=InventorCOPRA MetalBenderTDi sheet metal application for Inventor,with lofting, transitions, sheet metal partlibrary, flat pattern calculation, by dataM Software GmbHhttp://www.copra-metalbender.com ... 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Immersion Software/Proof Positive QA tool, allows users to detect, correctand prevent design/modeling faults, byAvatechhttp://www.avatechsolutions.com/ ... e/proofpositive.aspQuadrispace publishing software uses CAD files tocreate interactive 3D documents(reviews)/SMARTEAMIN Integration Autodesk Inventor integration for theSMARTEAM environment forcollaborative PDM/main.asp...cLangId=&IS=&InsPF=SketchCalc allows Autodesk Inventor users tocalculate several importantsection-properties of an active sketch,with just one mouse click/SPI Sheetmetal Inventor design and unfolding of complex sheetmetal parts with Autodesk Inventorhttp://www.spi.de/sheetmet/smi.htmTASys range of tolerance solutions including aTolerance Assistant, ToleranceAnalysis System and ToleranceOptimizer fully integrated to work withboth SolidWorks and Solid Edge/ToleranceCalc add-on tool to calculate acceptabletolerances by running quick simulationson a single part or combination ofseveral parts in an assembly, byGEOMATE 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EFFICIENT FEATURE EXTRACTION FOR2D/3D OBJECTSIN MESH REPRESENTATIONCha Zhang and Tsuhan ChenDept.of Electrical and Computer Engineering,Carnegie Mellon University 5000Forbes Avenue,Pittsburgh,PA15213,USA{czhang,tsuhan}@ABSTRACTMeshes are dominantly used to represent3D models as they fit well with graphics rendering hardware.Features such as volume,moments,and Fourier transform coeffi-cients need to be calculated from the mesh representation efficiently.In this paper,we propose an algorithm to cal-culate these features without transforming the mesh into other representations such as the volumetric representa-tion.To calculate a feature for a mesh,we show that we can first compute it for each elementary shape such as a triangle or a tetrahedron,and then add up all the values for the mesh.The algorithm is simple and efficient,with many potential applications.1.INTRODUCTION3D scene/object browsing is becoming more and more popular as it engages people with much richer experience than2D images.The Virtual Reality Modeling Language (VRML)[1],which uses mesh models to represent the3D content,is rapidly becoming the standard file format for the delivery of3D contents across the Internet.Tradition-ally,in order to fit graphics rendering hardware well,a VRML file models the surface of a virtual object or envi-ronment with a collection of3D geometrical entities,such as vertices and polygons.In many applications,there is a high demand to calcu-late some important features for a mesh model,e.g.,the volume of the model,the moments of the model,or even the Fourier transform coefficients of the model.One ex-ample application is the search and retrieval of3D models in a database[2][3][9].Another example is shape analysis and object recognition[4].Intuitively,we may calculate these features by first transforming the3D mesh model into its volumetric representation and then finding these features in the voxel space.However,transforming a3D mesh model into its volumetric representation is a time-consuming task,in addition to a large storage requirement [5][6][7].Work supported in part by NSF Career Award9984858.In this paper,we propose to calculate these features from the mesh representation directly.We calculate a fea-ture for a model by first finding it for the elementary shapes,such as triangles or tetrahedrons,and then add them up.The computational complexity is proportional to the number of elementary shapes,which is typically much smaller than the number of voxels in the equivalent volu-metric representation.Both2D and3D meshes are consid-ered in this paper.The result is general and has many po-tential applications.The paper is organized as follows.In Section2we discuss the calculation of the area/volume of a mesh.Sec-tion3extends this idea and presents the method to com-pute moments and Fourier transform for a mesh.Some applications are provided in Section4.Conclusions and discussions are given in Section5.2.AREA/VOLUME CALCULATIONThe computation of the volume of a3D model is not a trivial work.One can convert the model into a discrete3D binary image.The grid points in the discrete space are called voxels.Each voxel is labeled with‘1’or‘0’to indi-cate whether this point is inside or outside the object.The number of voxels inside the object,or equivalently the summation of all the voxel values in the discrete space, can be an approximation for the volume of the model. However,the transforming from a3D mesh model into a binary image is very time-consuming.Moreover,in order to improve the accuracy,the resolution of the3D binary image needs to be very high,which can further increase the computation load.2.1.2D Mesh AreaWe explain our approach starting from the computation of areas for2D meshes.A2D mesh is simply a2D shape with polygonal contours.As shown in Figure1,suppose we have a2D mesh with bold lines representing its edges. Although we can discretize the2D space into a binary image and calculate the area of the mesh by counting the pixels inside the polygon,doing so is very computationally intensive."positive"area "negtive"areaFigure 1:The calculation of a 2D polygon area To start with our algorithm,let us make the assump-tion that the polygon is close.If it is not,a contour close process can be performed first [9].Since we know all the vertices and edges of the polygon,we can calculate the normal for each edge easily.For example,edge AB in Figure 1has the normal:2122121212)()(ˆ)(ˆ)(y y x x y x x xy y N AB −+−−+−−=(1)where (x 1,y 1)and (x 2,y 2)are the coordinates of vertices Aand B ,respectively,and xˆand y ˆare the unit vectors for the axes.We define the normal here as a normalized vec-tor which is perpendicular to the corresponding edge and pointing outwards of the mesh.In computer graphics lit-erature,there are different ways to check whether a point is inside or outside a polygon [8],thus it is easy to find the correct direction of the ter we will show that even if we only know that all the normals are pointing to the same side of the mesh (either inside or outside,as long as they are consistent),we are still able to find the correct area of the mesh.After getting the normals,we construct a set of trian-gles by connecting all the polygon vertices with the origin.Each edge and the origin form an elementary triangle,which is the smallest unit for computation.We define the signed area for each elementary triangle as below:The magnitude of this value is the area of the triangle,while the sign of the value is determined by checking the posi-tion of the origin with respect to the edge and the direction of the normal.Take the triangle OAB in Figure 1as an example.The area of OAB is:.)(212112y x y x S OAB +−=(2)The sign of S OAB is the same as the sign of the inner prod-uct AB N OA ⋅,which is positive in this case.The total area of the polygon can be computed by summing up all the signed areas .That is,¦=ii total S S (3)where i goes through all the edges or elementary triangles.Following the above steps,the result of equation (3)is guaranteed to be positive,no matter the origin is inside oroutside the mesh.Note here that we do not make any as-sumption that the polygon is convex.In real implementation,we do not need to check the signs of the areas each time.Let:().'',21'2112¦=+−=ii total i i i i i S S y x y x S (4)where i stands for the index of all the edges or elementary triangles.(x i1,y i1),(x i2,y i2)are coordinates of the starting point and the end point of edge i .When we loop through all the edges,we need to keep forwarding so that the in-side part of the mesh is always kept at the left hand side or the right hand side.According to the final sign of the result S’total ,we may know whether we are looping along the right direction (the right direction should give the positive result),and the final result can be simply achieved by tak-ing the magnitude of S’total .2.2.3D CaseWe can extend the above algorithm into the 3D case.In a VRML file,the mesh is represented by a set of vertices and polygons.Before we calculate the volume,we do some preprocessing on the model and make sure that all the polygons are triangles.Such preprocessing,called tri-angulation,is commonly used in mesh coding,mesh signal processing,and mesh editing.The direction of the normal for a triangle can be determined by the order of the verti-ces and the right-hand rule,as shown in Figure 2.The con-sistent condition is very easy to satisfy.For two neighbor-ing triangles,if the common edge has different directions,then the normals of the two triangles are consistent.For example,in Figure 2,AB is the common edge of triangle ACB and ABD .In triangle ACB ,the direction is from B to A ,and in triangle ABD ,the direction is from A toB ,thus N ACB and N ABD are consistent.BFigure 2:Normals and order of verticesIn the 3D case,the elementary calculation unit is a tet-rahedron.For each triangle,we connect each of its vertices with the origin and form a tetrahedron,as shown in Figure 3.As in the 2D case,we define the signed volume for each elementary tetrahedron as:The magnitude of its value is the volume of the tetrahedron,and the sign of the value is determined by checking if the origin is at the same side as the normal with respect to the triangle.In Figure 3,tri-2,z 2)Figure 3:The calculation of 3D volumeangle ACB has a normal N ACB .The volume of tetrahedron OACB is:.)(61321312231213132123z y x z y x z y x z y x z y x z y x V OACB +−−++−=(5)As the origin O is at the opposite side of N ACB ,the sign of this tetrahedron is positive.The sign can also be calculated by inner product ACB N OA ⋅.In real implementation,again we only need to com-pute:()¦=+−−++−=iitotal i i i i i i i i i i i i i i i i i i i V V z y x z y x z y x z y x z y x z y x V ''.61'321312231213132123(6)where i stands for the index of triangles or elementary tetrahedrons.(x i1,y i1,z i1),(x i2,y i2,z i2)and (x i3,y i3,z i3)are coordinates of the vertices of triangle i and they are or-dered so that the normal of triangle i is consistent with others.Volume of a 3D mesh model is always positive.The final result can be achieved by take the absolute value of V’total .In order to compute other 3D model features such as moments or Fourier transform coefficients,we reverse the sequence of vertices for each triangle if V’total turns out to be negative.3.MOMENTS AND FOURIER TRANSFORMThe above algorithm can be generalized to calculate other features for 2D and 3D mesh models.Actually,whenever the feature to be calculated can be written as a signed sum of features of the elementary shape (triangle in the 2D case and tetrahedron in the 3D case),and the feature of the elementary shape can be derived in an explicit form,the proposed algorithm applies.Although this seems to be a strong constrain,many of the commonly-used fea-tures fall into this category.For example,all the features that have the form of integration over the space inside the object can be calculated with this algorithm.This includes moments,Fourier transform,wavelet transform,and many others.In classical mechanics and statistical theory,the con-cept of moments is used extensively.In this paper,themoments of a 3D mesh model are defined as:³³³=dxdydzz y x z y x M r q p pqr ),,(ρ(7)where ),,(z y x ρis an indicator function:¯®=otherwise.,0meshthe inside is z)y,(x,if ,1),,(z y x ρ(8)and p ,q ,r are the orders of the moment.Central moments can be obtained easily from the result of equation (7).Since the integration can be rewritten as the sum of inte-grations over each elementary shape:¦³³³=ii r q p i pqr dxdydz z y x z y x s M ),,(ρ(9)where ),,(z y x i ρis the indicator function for elementary shape i ,and s i is the sign of the signed volume for shape i .We can use the same process as that in Section 2to calculate a number of low order moments for triangles and tetrahedrons that are extensively used.A few examples for the moments of a tetrahedron are given in the Appendix.More examples can be found in [9].Fourier transform is a very powerful tool in many sig-nal processing applications.The Fourier transform of a 2D or 3D mesh model is defined by the Fourier transform of its indicator function:³³³++−=Θdxdydzz y x e w v u zw yv xu i ),,(),,()(ρ(10)Since Fourier transform is also an integration over the space inside the object,it can also be calculated by de-composing the integration into integrations over each ele-mentary shape.The explicit form of the Fourier transform of a tetrahedron is given in the Appendix.As the moments and Fourier transform coefficients of an elementary shape are explicit,the above computation is very efficient.The computational complexity is O (N),where N is the number of edges or triangles in the mesh.Note that in the volumetric approach,where a 2D or 3D binary image is obtained first before getting any of the features,the computational complexity is O (M),where M is the number of grid points inside the model,not consid-ering the cost of transforming the data representation.It is obvious that M is typically much larger that N ,especially when a relatively accurate result is required and the resolu-tion of the binary image has to be large.The storage space required by our algorithm is also much smaller.Previous work by Lien and Kajiya [10]provide a similar method for calculating the moments for tetrahe-drons.Our work gives more explicit forms of the moments and extends their work to calculating the Fourier trans-form.4.APPLICATIONSA good application of our algorithm is to find the principal axes of a 3D mesh model.This is useful when we want to compare two 3D models that are not well aligned.In a 3Dmodel retrieval system [2][9],this is required because some of the features may not be invariant to arbitrary rota-tions.We construct a 3x3matrix by the second order mo-ments of the 3D model:.002011101011020110101110200»»»¼º«««¬ª=M M M M M M M M M S (11)The principal axes are obtained by computing the ei-genvectors of matrix S ,which is also known as the princi-ple component analysis (PCA).The eigenvector corre-sponding to the largest eigenvalue is made the first princi-pal axis.The next eigenvector corresponding to the secon-dary eigenvalue is the second principal axis,and so on.Inorder to make the final result unique,we further make sure that the 3rd order moments,M 300and M 030,are positive after the transform.Figure 4shows the results of this algo-rithm.Before rotationAfter rotationBefore rotation After rotationFigure 4:3D models before and after PCAThe Fourier transform of a 3D mesh model can be used in many applications.For example,the coefficients can be directly used as features in a retrieval system [9].Other applications are shape analysis,object recognition,and model matching.Note that in our algorithm,the result-ing Fourier transform is in continuous form.There is no discretization alias since we can evaluate a Fourier trans-form coefficient from the continuous form directly.5.CONCLUSIONS AND DISCUSSIONSIn this paper,we propose an algorithm for computing fea-tures for a 2D or 3D mesh model.Explicit methods to compute the volume,moments and Fourier transform from a mesh representation directly are given.The algorithm is very efficient,and has many potential applications.The proposed algorithm still has some room for im-provement.For example,it is still difficult to get the ex-plicit form of a high order moment for a triangles and tet-rahedrons.Also the Fourier transform may lose its compu-tational efficiency if many coefficients are required simul-taneously.More research is in progress to speed this up.REFERENCES[1]R.Carey,G.Bell,and C.Marrin,“The Virtual Reality Modeling Language”.Apr.1997,ISO/IEC DIS 14772-1.[Online]:/Specifications/.[2]Eric Paquet and Marc Rioux,“A Content-based Search Engine for VRML Database”,Computer Vision and Pattern Recognition,1998.Proceedings.1998,IEEE Computer Society Conference on ,pp.541-546,1998.[3]Sylvie Jeannin,Leszek Cieplinski,Jens Rainer Ohm,Munchurl Kim,MPEG-7Visual part of eXperimentation Model Version 7.0,ISO/IEC JTC1/SC29/WG11/N3521,Beijing,July 2000.[4]Anthony P.Reeves,R.J.Prokop,Susan E.Andrews and Frank P.Kuhl,“Three-Dimensional Shape Analysis Using Moments and Fourier Descriptors”,IEEE Trans.Pattern Analysis and Machine Intelligence ,pp.937-943,Vol.10,No.6,Nov.1988.[5]Homer H.Chen,Thomas S.Huang,“A Survey of Construction and Manipulation of Octrees”,Computer Vision,Graphics,and Image Processing ,pp.409-431,Vol.43,1988.[6]Shi-Nine Yang and Tsong-Wuu Lin,“A New Linear Octree Con-struction by Filling Algorithms”,Computers and Communications,1991.Conference Proceedings.Tenth Annual International Phoenix Conference on ,pp.740-746,1991.[7]Yoshifumi Kitamura and Fumio Kishino,“A Parallel Algorithm for Octree Generation from Polyhedral Shape Representation”,Pattern Recognition,1996.Proceedings of the 13th International Conference on ,pp.303-309,Vol.3,1996.[8]James D.Foley,Andries van Dam,Steven K.Feiner,and John F.Hughes,Computer Graphics principles and practice,Second Edition ,Addison-Wesley Publishing Company,Inc.,1996.[9]/projects/3DModelRetrieval/.[10]Sheue-ling Lien and James T.Kajiya,“A Symbolic Method for Calculating the Integral Properties of Arbitrary Nonconvex Polyhedra”,IEEE Computer Graphics and Applications ,pp.35-41,Oct.1984.APPENDIX().61321312231213132123000z y x z y x z y x z y x z y x z y x M +−−++−=().00032110041M x x x M ++=().000313221232221200101M x x x x x x x x x M +++++=()000321212331223221333231300x x x )()()(201M x x x x x x x x x x x x M +++++++++=))()((i))()((e *i ))()((e *i ))()((e *i (*),,(333222111323232313131333)wz vy i(ux 323232212121222)wz vy i(ux 313131212121111)wz vy i(ux 000333222111wz vy ux wz vy ux wz vy ux wz wz vy vy ux ux wz wz vy vy ux ux wz vy ux wz wz vy vy ux ux wz wz vy vy ux ux wz vy ux wz wz vy vy ux ux wz wz vy vy ux ux wz vy ux M w v u ++++++−+−+−+−+−+−+−+++−+−+−+−+−+−+++−+−+−−+−+−++=ℑ++++++。
