炼油生产调度专家系统的应用研究

基于知识的优化设计应用于炼油化工厂,采用专家系统技术将生产中成功的经验和领域专家的知识组织起来,协调并参与数学规划建模过程,优化编排调度作业计划,并进行优化控制和管理.文章结合大型炼油厂的生产实际,探索智能化的管控一体化的新模式.     

Solving Third Order Differential Equations with Maximal Symmetry Group

The largest group of Lie symmetries that a third-order ordinary differential equation (ode) may allow has seven parameters. Equations sharing this property belong to a single equivalence class with a canonical representative v ^′′′(u)=0. Due to this simple canonical form, any equation belonging to this equivalence class may be identified in terms of certain constraints for its coefficients. Furthermore a set of equations for the transformation functions to canonical form may be set up for which large classes of solutions may be determined algorithmically. Based on these steps a solution algorithm is described for any equation with this symmetry type which resembles a similar scheme for second order equations with projective symmetry group. Received March 9, 2000; revised June 8, 2000     

Binding Virtual Environments to Toolkit Capabilities

There are many toolkits and development environments that aid the process of constructing virtual environment applications. Many of these development environments encourage customising a virtual environment's design while rapid prototyping within the confines of a toolkit's capabilities. Thus the choice of the technology and its associated support has been made independent of the end-use requirements of the final system. This can bias a virtual environment's design by implementation based constraints. We propose that an alternative approach is the consideration of virtual environment requirements in the context of an inspectable design model, to identify the requirements that a toolkit will need to support. In the context of an example, we present a selection of design requirements that we consider important for virtual environment design in general. We explore how these requirements might be mapped to different capabilities using Virtual Reality Modelling Language (VRML) as a concrete example of a platform technology.     

A Novel Approach Makes Higher Order Wavelets Really Efficient for Radiosity

Since wavelets were introduced in the radiosity algorithm ⁵, surprisingly little research has been devoted to higher order wavelets and their use in radiosity algorithms. A previous study ¹³ has shown that wavelet radiosity, and especially higher order wavelet radiosity was not bringing significant improvements over hierarchical radiosity and was having a very important extra memory cost, thus prohibiting any effective computation. In this paper, we present a new implementation of wavelets in the radiosity algorithm, that is substantially different from previous implementations in several key areas (refinement oracle, link storage, resolution algorithm). We show that, with this implementation, higher order wavelets are actually bringing an improvement over standard hierarchical radiosity and lower order wavelets.     

Interpolatory √3-Subdivision

We present a new interpolatory subdivision scheme for triangle meshes. Instead of splitting each edge and performing a 1-to-4 split for every triangle we compute a new vertex for every triangle and retriangulate the old and the new vertices. Using this refinement operator the number of triangles only triples in each step. New vertices are computed with a Butterfly like scheme. In order to obtain overall smooth surfaces special rules are necessary in the neighborhood of extraordinary vertices. The scheme is suitable for adaptive refinement by using an easy forward strategy. No temporary triangles are produced here which allows simpler data structures and makes the scheme easy to implement.     

基于彩色图像的指示标志检测

智能交通系统是近年来国内外广泛关注的研究课题,在基于计算机视觉系统的交通标志识别中,关键步骤之一是如何快速有效地检测并提取交通标志。该文提出了基于色彩的指示标志检测与提取的快速有效方法。它包括：对实景图像进行色调不变的彩色增强,彩色聚类,形态滤波,模板匹配,特征点判别等步骤。最后,由搜索到的特征点从增强后的彩色图像中抽取指示标志。实验显示该方法能快速有效地从实景图像中检测指示标志。     

基于主控流动的多级Multi-Agent系统

从分析人的思维活动着手,提出了模拟人类智能活动过程构筑Ｍｕｌｔｉ－Ａｇｅｎｔ系统的方法,并由该方法构造了基于主控流动的多级Ｍｕｌｔｉ－Ａｇｅｎｔ系统。其主要特点是把小 Ｍｕｌｔｉ－Ａｇｅｎｔ系统视为一个特殊的Ａｇｅｎｔ,并由这种特殊的Ａｇｅｎｔ组成更高一级的Ａｇｅｎｔ系统…从而形成多级Ｍｕｌｔｉ－Ａｇｅｎｔ系统,而且在每一级Ａｇｅｎｔ系统中均采用了主控流动策略,使得整个系统能够把巨量的Ａｇｅｎｔ有效地结合起来。系统效率高,能主动改变和适应环境,为设计具体的大规模Ｍｕｌｔｉ－Ａｇｅｎｔ系统提供了一种可行的解决方案。     

可编程S盒及反馈移位寄存器的设计方法

可编程S盒和可编程反馈移位寄存器是可编程密码芯片的两个重要的部件。文章给出了可编程S盒和可编程反馈移位寄存器的一种逻辑设计方法,按照该方法设计的S盒能够通过编程实现任意的布尔逻辑函数,按照该方法设计的反馈移位寄存器能够通过编程灵活地改变反馈抽头和反馈函数。     

一种中文文档的非受限无词典抽词方法

本文提出了一种非受限无词典抽词模型,该模型通过自增长算法获取中文文档中的汉字结合模式,并引入支持度、置信度等概念来筛选词条。实验表明:在无需词典支持和利用语料库学习的前提下,该算法能够快速、准确地抽取中文文档中的中、高频词条。适于对词条频度敏感,而又对计算速度要求很高的中文信息处理应用,例如实时文档自动分类系统。     

单片机多红红外通信系统的设计与实现

本文提出了一种利用软件方法实现单片机多机红外通信的设计方案。该方案减少了通信系统的硬件复杂性,降低了成本,提高了通信的灵活性。文中介绍介绍了方案的设计思想,包括硬件设计原理、信息格式的设计与差错控制的实现、信息答应机制以及软件核心框架等,同时指明了设计的应用前景。实践证明,效果比较理想。