智能辅导系统中图形自动调整设计与实现

简要介绍了利用面象对象的编程技术，用Java语言实现了平面几何图形的自动洞整。系统是整个网络智能辅导系统的一个部分，整个辅导系统属于一个专家系统。本系统设计的对象是中学生，在客户端用户只需要输入简单的几何图形，只要图形的拓扑结构正确，通过自动调整模块后将使原来的图形变成标准的符合题意的图形。在调整的实现过程中提出了“约束”的概念，从而使得调整得以实现。     

面向对象的通用作图系统

传统作图系统是主要是利用无逻辑关联的点，线，弧线等基本几何图形进行构图这极端不符合人们的日常思维习惯，文中构造了一个面向对象的作图模型。在该模型中，通过概括和聚集建立起对象的共享属性和操作机制，并在此基础上实现了一个原型系统，整个作图过程针对图形对象，大大地提高了作图效率，并且作图环境易于扩充。     

一种基于可处理不等式约束的动态几何自动作图软件GeoDraw

针对目前大部分几何作图软件只能处理等式约束的不足,设计并实现一种基于可处理不等式约束的动态几何自动作图软件GeoDraw。该软件应用符号和数值混合计算,将构造式和生成式作图方法相结合,可以有效地生成含有不等式约束的动态几何图形,能通过鼠标点击和拖拽图形中的自由元素改变更新图形,并且在图形变化中动态地保持几何约束关系,主要应用于几何教学与研究。整个作图过程包括Maple中的三角分解,QEPCAD中的实量词消去以及Java中的语义解析、数值计算和图形生成等,且是完全自动的。     

CAD中的图形尺寸自动修改

国內外二维图形系统只能对图形作逐线段的修改,如果只修改一个线段,势必影响其它线段的位置,往往会导致图形的重新绘制,不易显示出CAD系统的优越性。本文应用尺寸回路原理,使图形上某个尺寸修改以后,其它相关尺寸就自动跟着修改,仍旧保持原来的几何形状, 大大地节省了设计绘图的时间。本文建立了尺寸和图形之间双向交互关系,从一个新的角度初步解决了几何图形的精确定位的问题。     

可复用的列车运行图调整系统的设计

由于计算机自动生成的运行图可能仍不能满足实际运营组织的需要,需要对其进行手工调整,因此运行图调整系统成为计算机编制运行图系统的重要组成部分。该文讨论了一种可复用和易扩展的运行图调整系统的设计,其中介绍了包括数据结构、图形显示及调整操作的设计。同时也介绍了一种基于约束的调整算法。这些设计大部分在上海地铁列车运行图自动编制系统中实现。     

虚拟加工环境中的三维图形数据结构的研究

在虚拟加工环境中,三维图形的处理是一个中心的技术问题,主要包括,三维图形的几何建模方法;三维几何图形的显示数据结构;三维图形的编译处理等,提出了一种能够满足虚拟加工环境的三维图形的数据结构,实现了三维图形的环境人,毛坯的对接等功能。     

基于知识库的上机自动辅导系统的研究与实现

研究并实现了基于知识库的高级语言上机自动辅导系统,该系统可管理多种高级语言的知识库,也是一个基于WWW的网络应用系统。重点论述了系统的设计与系统的实现。     

基于JGraph的变电站综合自动化图形组态系统

JGraph是一套使用Java开发的、兼容Swing的开源图形组件,具有丰富的图形操作接口和良好的可扩展性。该文基于JGraph实现一个跨平台的变电站综合自动化图形组态系统。与现有图形组态系统相比,该系统具有更好的自动处理能力,能实现电力系统设备的自动检测和接线图的自动生成,简化传统变电站图形系统在接线图设计方面的工作。     

基于图形识别的建筑图钢筋自动统计系统CSC

介绍了一个建立于图形理解基础上的钢筋自动统计系统CSC。CSC系统充分利用图形识别技术与人工智能方法,其实现可分为两个阶段：1）利用图形识别技术与非精确推理等方法,实现建筑符号的自动识别。2）采用基于动态数据库的知识表示与推理方法,结合建筑领域的专业知识实现钢筋用量的自动统计。     

一个简单笔式交互系统的实现

以用户为中心的思想,引入笔交互风格,运用Fonseca和Jorge提出的模糊逻辑识别算法,采用了中科院软件所的笔式应用开发平台PenUI作为底层支撑,设计并实现了一个能识别基本几何图形和简单手势的交互式系统.所采用的识别算法是一种识别多笔画几何草图简单方法.它利用图形的暂时邻接关系和全局几何特征来识别一些简单的几何图形,其中有实线和虚线两种.     

一种基于视觉特性的三角网格简化算法

在计算机图形学和几何造型中,实体模型经常采用多边形网格描述,由于绘制时间和存储量与网格的数量成正比,因此复杂的网格模型通常并不实用,从而必须进行模型简化。因为任意多边形可以很方便地被剖分为三角形,由此该文提出一种新的基于视觉特性的三角形网格简化算法。该算法基于人类的视觉特性对三角形网格进行重要性分析,模型细节的选择取决于整个模型对视觉效果的贡献程度,在用户指定的尺度范围内,通过采用收缩三角形以达到迅速简化的目的,以较小的图形生成代价获取丰富的图形视觉效果。实验结果表明,该算法具有实现简单,速度快的特点,能有效地支持细节层次模型的表示。     

基于自适应Runge-Kutta法的织物动态模拟

运动微分方程的数值求解，是实现基于物理模型的织物仿真的技术关键。针对具有高精度要求的织物动态仿真，提出利用显式Runge-Kutta高阶方法解决仿真过程中运动微分方程的求解问题，并采用内嵌的Cash-Karp计算格式，从自动调整步长和控制精度两方面优化算法。实验证明，基于内嵌的Runge-Kutta自适应法精度高，易实现，具备良好的稳定性，并可直接获取误差，自动调整步长确保精度，使系统的求解效率得以进一步提高。     

Graphics as an expert system user interfacing media

This paper demonstrates the usefulness of using graphics as an user interfacing media in expert systems. The graphics interfacing ability of the Personal Consultant Plus, an expert system development tool, is examined. A graphics image can be created by a graphics editor or a sophisticated drafting software package, such as TelePaint, PC Palette, Story Board, AutoCAD, etc. The graphics image can then be captured and utilized in the expert system in various ways. The user interface using graphics makes an expert system easier to use and to understand.     

Visual C#.NET实现用户自定义图形编程方法

信息系统终端用户可以自己绘制图形,以鼠标拖拽的方式实现已绘制图形的移动、缩放等功能,不仅会极大地方便用户使用,同时可以满足用户现场绘图的需求。对如何在信息管理系统中实现用户自定义图形进行分析和设计,并在Visual C#.NET编程环境中使用GDI＋等技术实现用户自定义图形,使终端用户能够动态创建可以用鼠标拖拽方式移动、缩放的图形,实现直线、矩形、文本的创建、移动、缩放功能,绘制的图形可以保存为XML文件,可以加载已保存XML文件。文中描述了自定义图形编程方法的设计和实现。     

Crystal gazing in computer graphics

We, the people, are in the midst of the age of the computer. We are at the beginning of the age of computer graphics. This article will crystal gaze upon a few of the areas of life which are beginning to be and soon will be very affected by computer graphics. Topics vary from homes and cities; hardware and animation; Congress and business; and architecture and drafting to art. These show that the future uses of computer graphics are limited only by the imagination.

Underlying the whole gamut is the theme that computer graphics must be user oriented! The application user must not be required to know anything about computers or their languages or how to manipulate complex mathematics!     

Architecture without numbers — CAAD based on a 3D modelling system

The paper describes an advanced demonstration system which brings together a number of recent developments in CAAD (computer-aided architectural design). This demonstration system illustrates how an important new form of input device, a 3D modelling systemm can be linked with building performance software and ‘indicative’ computer output graphics. The 3D modelling system uses electronically interrogable building elements. The user assembles these elements on a baseboard, providing a tangible model of the design. The model is then interrogated by the CAD system, which recovers the geometry data describing the topology of the model. The user changes the design by reassembling the model elements. A particular aspect of this demonstration is that the user has the option to generate building design data and assimilated building performance data without the need to handle this data in numeric form. It is likely that many of the features present in this demonstration system will be evident in future ‘production’ CAAD systems.     

基于采矿CAD的硐室参数绘图系统设计及实现

CAD系统因其本身具有许多长处,得到了工程设计人员的广泛使用。但它只能处理图形的几何信息,真正具有工程实际意义的图形拓扑信息和参数约束信息均被抛弃了。为了保留更多的图形信息以及让工程设计人员更方便地进行硐室图形的绘制,文中根据采矿CAD图形的特点,把要绘制的硐室图形进行参数化分析,并通过编程调用采矿CAD的接口实现了硐室图形的自动绘制系统。此系统能根据用户输入的参数自动生成硐室的二维和三维图形,这大大减少了设计人员的工作量,提高了设计效率,也有利于计算机辅助设计的进一步发展。     

Practical computer graphics for scientific users: Philosophy and implementation

The scientific computer user presents a unique challenge to the graphics system designer. If the graphics system is properly designed and implemented, computer graphics becomes a vital research tool for the scientific user. These users' desires and expectations play an important role in every phase of the design process.This paper describes the philosophy of the graphics system at the National Center for Atmospheric Research (NCAR) and its implementation. Details of algorithms are not presented; rather the purpose has been to describe a successful computer graphics system which may serve as a guide for other designers who desire to provide practical computer graphics. This graphics system operates under a batch-mode computer system without using interactive terminals.     

Semantic feedback in the Higgens UIMS

Almost all applications using interactive graphics contain important structures and concepts which are deeper than the geometres used to display them to the user. One of the major tasks of the system implementer is to cause the user interface to reflect this deeper structure accurately so that it may be directly manipulated by the user. The authors describe a tool, the Higgens user interface management system (UIMS), which can automate much of this task for a wide class of systems using interactive graphics. It is able to generate graphical user interfaces automatically from a high-level interface specification. These specifications are primarily nonprocedural in nature. They describe how graphical images can be automatically derived and updated based on applications entities, and how graphical inputs can be translated back into terms which are appropriate to the application     

Dynamic illustrative graphics for simulations

In any graphics application, the environment created by the system designer is of utmost importance. A variety of good input devices, effective real time displays, ease of interaction with graphical elements and with system instructions can all contribute to a friendly environment. A graphics system designed for simulations with a facility for adding both abstract dynamic graphics and user control is enhanced by the addition of features uncommon to other graphics systems. These features, and their values and the ways in which they contrast with more traditional graphics systems, will be described.