Presidential Young Investigator Award

该项目涉及数据库研究的三个领域; 几何数据、文本和多媒体文件系统以及多个 磁盘文件分配。 寻找最好的方法来管理 几何数据，几个有前途的方法将进行分析， 用于比较。 重点将放在空间上 填充曲线和分形，如皮亚诺曲线，希尔伯特 曲线，基于格雷码的曲线，因为它们导致良好的 距离保持映射 第二个项目涉及 开发多媒体文件归档系统。 小说 该系统的特点是，它将使用签名文件 至于文本检索，它将使用光盘存储， 将允许静态和动画图像的文件。 将文件存储在多个磁盘上的去集群技术， 将研究最大化平行度。 这个目标是 与第一个项目相反。 问题是将不相似的分组 记录在同一个磁盘上。 一种启发式的方法， 理论和纠错码，因为这样的码字 代码是故意不相似的。 初步 实验表明，这种启发式始终优于 更古老的特殊化学。

This project is concerned with three areas of database research; geometric data, text and multimedia filing sytems and multiple disk file allocations. In search of the best method to manage geometric data, several promising methods will be analyzed and implemented for comparison. Emphasis will be given to space filling curves and fractals, such as the Peano curve, the Hilbert curve, curves based on Gray codes, because they lead to good distance preserving mappings. The second project involves the development of a multimedia document filing system. The novel characteristics of the system is that it will use signature files for text retrieval, it will use optical disks for storage and it will allow static and animated images in the documents. Declustering techniques that store a file on multiple disks to maximize the parallellism will be studied. This goal is the inverse of the first project. The problem is to group unsimilar records on the same disk. A heuristic that uses information theory and error correcting codes, because the codewords of such codes are deliberately unsimilar has been developed. Preliminary experiments show that this heuristic consistently outperforms older ad hoc heuristics.