Geostar地图符号的实现方法

对面向对象的 Ｇ Ｉ Ｓ软件— Ｇｅｏｓｔａｒ 中地图符号的实现方法进行了研究。分析了 Ａｕｔｏ Ｃ Ａ Ｄ, Ａｒｃ／ Ｉ Ｎ Ｆ Ｏ 符号组织情况及其特点;用面向对象的方法对 Ｇ Ｉ Ｓ地图符号进行了抽象分类和组织;在分析符号的绘制、表示和存贮特点的基础上,提出了基于｛ 代码（ 图素代码或函数代码） ＋ 参数｝ 符号库的建立方法;提出了７ 位数字字符的方法建立《地形图图式》符号代码的方案,该方案便于建立分类与分类索引机制;对面向对象 Ｇ Ｉ Ｓ 中地图符号的组织提出了合理性的方案：通过“对照表”将空间对象与符号库联系起来,可以减少空间对象数字化和空间对象符号化时的麻烦;采用拷贝临时数据库和建立元文件索引的方法,为 Ｇ Ｉ Ｓ 获得较好的地图输出效果提供了良好的手段。     

面向对象的土地覆盖信息提取方法研究

利用遥感方法提取土地覆盖信息时,常用的自动分类方法只能利用遥感数据的光谱信息,而面向对象的分类方法在综合利用遥感数据光谱信息、纹理特征、拓扑关系和加入专题信息进行多尺度分割获取对象后的基础上,通过对对象的目视识别建立模糊判别函数来进行分类。利用面向对象的方法成功提取了三峡库区奉节县中部的土地覆盖信息,得到了较为满意的结果,利用野外采样数据进行验证其精度达89.2%。     

遥感图像分类方法评析与展望

从遥感图像分类的基本概念和特征出发,在对各算法进行划分基础上,分析评价了主要遥感图像分类方法的原理、特点,优势与限制,并阐明了各主要方法作用及其意义,指出目前存在的问题,展望了遥感图像分类方法的发展与应用前景。     

一种基于OGRE图形引擎的实时分布式渲染系统

虚拟现实的实时交互得到了越来越广泛地应用,实时分布式渲染有效地解决了普通PC机渲染的时间瓶颈问题,提高了系统实时渲染性能和输出分辨率。在对分布式渲染原理研究分析的基础上,依据设计模式的思想,设计了一种基于Sort-First结构的实时分布式渲染框架和同步机制,并在实践中应用OGRE图形引擎实现了该系统。     

基于面向对象信息提取技术的城市用地分类

针对高分辨率遥感影像的城市用地分类,引入了面向对象的信息提取技术,并将其与传统基于像素光谱信息的分类方法进行了比较。在此基础上详述了面向对象信息提取的关键技术---多尺度影像分割和基于分割的分类技术。以城市作为研究区,实现城市用地的自动分类。图像处理过程包括几何校正、HIS融合、图像分割和图像分类。最终分类结果表明:视觉上,面向对象信息提取技术克服了传统方法无法克服的“椒盐”噪声的影响;精度上,面向对象信息提取技术的总体精度高达84.82%,比最大似然法的总体精度提高了10.95%,并且各类地物信息的提取精度均有所提高,其中草地、道路、建筑物阴影的精度较高。     

智能型国标公差自动标注系统的研究

在智能机械CAD系统ObjectD环境下，采用面向对象编程技术，用AQL语言编程实现国标公差自动标注的程序．     

Issues in the design of a parallel object-oriented language

This paper discusses the considerations that have played a role in the design of the language POOL2. This language integrates the structuring techniques of object-oriented programming with mechanisms for expressing parallelism. We introduce the basic principles of object-oriented programming and its significance for program development methodologies. Several approaches for integrating objects and parallelism are compared and arguments for the choices made in POOL2 are presented. We also explain why inheritance is not yet included in POOL2. A brief overview of the research in formal aspects of POOL is given. Finally we indicate some directions for future developments.     

Object management in a persistent smalltalk system

The main goal of the Alltalk project is to provide transparent database support to the Smalltalk programmer. As a first step towards this goal, the current version of Alltalk extends Smalltalk-80 by providing persistence to Smalltalk objects without adding a database sublanguage, new language syntax, classes or methods. This paper describes the implementation of object management in Alltalk, including database layout, database access methods, in-memory object management and high-level interface from the interpreter. It also discusses how the object manager is integrated in a unique way with the operations of the Alltalk garbage collector and interpreter.     

Object-oriented software modeling of a Flexible Manufacturing System

Flexible Manufacturing Systems play an important role in improving our manufacturing productivity. Simulation is emerging as a popular tool in modeling FMS for analyzing its performance in the area of production planning/scheduling. In this paper, we illustrate how to model a Flexible Manufacturing System in the object-oriented paradigm using an example. We present a systemtic approach to the design of object-oriented programming systems based on a combination of data modeling and event analysis techniques.An entity relationship approach is used as the basis for an initial decomposition of the system into objects. The design is refined by an analysis of the events the objects participate in. The design is implemented in Objective-C. Finally, we describe ways in which this model of an FMS can be extended to explore popular research questions in production planning and scheduling.     

Visual Zero: A persistent and interactive object-oriented programming environment

In this article, an ongoing research project held in the Computer Science department of the University of Vigo is described. Its main objective is to develop an interactive object-oriented environment, serving as a vehicle for learning object-oriented programming. It currently consists of a virtual machine, an assembler, compilers for two high-level programming languages, and an educational visual programming environment. Its main characteristics are (a) the support of prototype-based object orientation, which is a model of object orientation that actually wraps the class-based model; (b) the support for object persistence, which simplifies all input/output issues to the minimum, and (c) the availability of a new visual programming environment is an invaluable help. We the authors think that the combination of all of these possibilities, will lead to an interesting, useful tool that would be recommended for object-oriented teaching. The whole system has been successfully employed in a number of different courses, allowing students to concentrate on objects and their relationships from the very beginning, and thus helping them to achieve a high degree of knowledge about the object-oriented programming paradigm.