程序可视化系统ProVS的设计和实现

本文研究程序代码可视化技术，即从现存的程序生成某种可视化表示，增强程序的易读性、易理解性和易维护性。首先介绍ＰｒｏＶＳ的设计思想和实现技术，然后给出输出例子。     

基于网络分布式窗口系统的图片绘制软件NuSlides的设计与实现

本文论述了设计和实现图片绘制软件NuSlides的主要技术问题。包括CC－NeWS窗口环境下应用软件开发的一般方法、NuSlides的功能设计和交互技术等，最后给出用NuSlides绘制的几个图例。     

数字印刷测试版的设计与应用研究

进入21世纪以来,数字印刷以其快速、高效、灵活、可变数据印刷的特点,具有广泛的应用领域。但由于数字印刷的作业特点,用于传统印刷的控制条无法作为其制版、印刷质量检验与控制的手段。为了实现印刷的数据化、规范化及标准化控制,我们必须设计出既能控制印刷过程又能控制印刷品质量的数字印刷测试版。从使用测控条目的和意义入手,本文采用PostScript语言编写出一种既能控制传统印刷过程,又能控制数字印刷质量的测控条,组合并输出为PS或EPS文件,把生成的PostScript数字印刷测控条与一般的质量控制元素如色彩再现等元素组合成数字印刷测试版,用于监控印刷过程,分析印刷品质量问题,实现对实地密度、网点扩大、印刷反差、阶调再现、叠印率、网点变形、重影、分辨率、印刷灰平衡等技术参数的控制。     

网络出版中的排版技术特点

目前大量的通讯数字流作业传送所采用的技术还是不完善的。传真技术只有160dpi的黑白分辨力,这使得要想得到某个图像好坏的真实效果非常困难,要想区分小的细节和字体就更加困难了。但是有了PDF,就可以用E-mail发送这些文件(文件可以做得足够小),并且附带解释。这些都可以作为PDF页面的一部分来描述必须要做的修改。而且,用这种PDF文件的副本     

Extracting text from PostScript

We show how to extract plain text from PostScript files. A textual scan is inadequate because PostScript interpreters can generate characters on the page that do not appear in the source file. Furthermore, word and line breaks are implicit in the graphical rendition, and must be inferred from the positioning of word fragments. We present a robust technique for extracting text and recognizing words and paragraphs. The method uses a standard PostScript interpreter but redefines several PostScript operators, and simple heuristics are employed to locate word and line breaks. The scheme has been used to create a full-text index, and plain-text versions, of 40,000 technical reports (34 Gbytes of PostScript). Other text-extraction systems are reviewed: none offer the same combination of robustness and simplicity. © 1998 John Wiley & Sons, Ltd.     

高速中文PostScript系统研究

PostScript为桌面设计过程中, 排版印刷的后端处理的开放标准。高速中文PostScript系统的实现涉及到多方面的技术我们一方面研究了中文PostScript系统的软件构成和算法另一方面, 设计并实现了基于Intel 80960CA超标量亿次处理器的高速中文PostScript处理硬件系统, 进一步将其扩充为分布式并行处理系统, 并在通用PC平台上实现单机和并行中文PostScript系统此外, 我们还提出了存储压缩等相关技术。本文探讨了上述系统的构成, 并对系统进行了测试和性能评价。测试表明, 我们通过采用这些高速的硬件系统及与其相适应的软件算法, 基本解决了中文’处理速度慢和成本高的问题。     

Composing Hierarchically Structured Images

This paper begins by examining the ‘classical’ raster-based composition model, establishing its weakness, and developing a new composition algebra based on line drawing. It then examines the role of composition in the Hierarchical Display Model, demonstrates that the forms of composition assumed in this model are inadequate to deal correctly with the interactions of two-dimensional representations of three-dimensional objects, and shows that our composition algebra resolves this difficulty. The composition steps required can be packaged with the use of a single attribute which constrains the apparent order of composition. This attribute is associated with the object which is to be taken ‘out of order’, obviating any needsfor layers.     

Technical Report Literature on the World Wide Web

Abstract

This article reviews and analyzes the current state of Web access to technical report literature. Besides locating sites for bibliographically identifying technical reports, it also looks at the ways the full-text of technical reports are being distributed. Where appropriate, it compares the electronic bibliographic control products with their print or formerly print equivalents. Most widely available at this point are federal government reports and computer science technical reports. Information on coping with the various file formats found at the sites is also provided. URLs to the various technical report sites and to sites dealing with the software applications needed to access the reports are included.