Gis ' s essential idea lies in combining the spatial geography graphic data with their expressed information , so realize to update graphic data and property information of spatial entities synchronously , to query bidirectionally , and to edit and operate graphic data Gis的基本思想在于把空间地理图形数据和其代表的地理信息有机地结合起来，从而实现了空间实体的图形数据与属性信息的同步更新，双向查询，以及图形数据的操作与编辑。
Based on the wavelet theory , the relation between multiresolution analysis and multi - scale data expression in gis is found , a new model of using multiresolution analysis is put forth , and the application example to use the proposed model is given in this paper 本文应用小波理论建立了多分辨率分析与gis图形数据多比例尺表达的关系,在此基础上提出了一种基于多分辨率分析的自动制图综合模型,并以线状要素自动综合为例,说明了新模型方法的应用。
Based on the mapgis software , this paper discusses the method of dividing layer , assigning layer , coding layer of graphic data and the method of coding id key character related to the attribute data in the process of establishing the geological disaster information database of wayaogou valley of xining city 摘要介绍了基于mapgis平台建立瓦窑沟流域地质灾害数据库过程中，图形数据的图层划分、命名、编码及与属性数据相连接的id关键字段的编码方法。
Reading graphics files and dispersing curves and surfaces . after lucubrating current algorithms dispersing trimmed surfaces , the mapping method is adopted . to avoid unnecessary or repeated calculations , a new tessellation algorithm for trimmed surface is introduced 在深入分析目前流行的裁剪曲面离散算法的基础上，采用映射法对裁剪曲面进行离散，并针对面向网络会议的图形浏览器要求图形数据、剖分速度快的特点，提出了一种基于编码的裁剪曲面离散算法； 3
Based on the activex technology , electric component menus and toolbars are created in this paper , with which a net wiring diagram for power electronics system is drawn . take advantage of autocad events , it is easy to fully carry out the consistency between graphics and data , from which users can manage databases and visual operation on graphics . the graphics about short - circuit current distribution and protection coupling are auto - drawn by using the autocad entity and text objects 本文采用activex技术，创建电气元件菜单和工具栏，方便用户绘制电力系统网络接线图；利用autocad事件，实现图形数据的一体化，从而可以使用户在图形上操作和管理数据库以及计算的可视化操作；利用autocad的图形和文本对象来自动绘制短路电流分布图和保护整定图。
The research results is briefed as follow . ( 1 ) a new communication and decision - making method is presented , which integrated several new tools as well as some old ones ; ( 2 ) a new concept of " virtual communicating place shared in real time by multi - user " is brought forward , and a new technology based on event - driving and message - transferring mechanism is designed to realize graphic data shared by multi - user and displayed synchronously under net environment , which is the basis of the whole system . ( 3 ) a new mechanism for team members to share data efficiently is devised , which supports collaborative working in progress , maintains the consistency of data , records the history of design and etc . by defining a new type of the design data attributes and the privilege of team member to access to data in different time , using a new method of data manipulating , the team data sharing is realized 本文的主要研究成果为： ( 1 )在研究国内外网络决策交流方式方法的基础上，综合多种方法的优点，提出了一种新的决策交流方式，采用了多种手段和工具，完善了网络决策交流的机制； ( 2 )提出了多用户共享的可视化虚拟交流空间的概念，并对其实现技术进行仔细的分析，针对目前存在的技术难点，提出了可行的解决方案，设计了一种新型的基于事件驱动和消息传递机制的多用户实时共享图形数据的解决方案，并采用了跨平台的java技术实现了网络环境下图形数据的实时交流和显示； ( 3 )针对团队协同的网络cad系统的特点和要求，提出了一种新的团队数据共享机制，通过对产品数据的基本属性、历史属性、共享状态属性和关联属性的定义，结合对团队成员在不同设计阶段的权限控制，采用新型的对共享数据库的数据操作方法，动态地维护团队数据的共享、设计的变更、设计进程的同步、关连数据的一致性、以及多个团队之间的数据交流。
