Detecting and extracting modi cations from information sources is an integral part of data warehousing. For unsophisticated sources, in practice it is often necessary to infer modi cations by periodically comparing snapshots of data from the source. We call this problem the snapshot di erential problem. We show that this is closely related to outerjoins. In this paper we extend the traditional ...

Current hypertext systems have been widely and effectively used on relatively small data volumes. The potential of database technology is explored for aiding the implementation of hypertext systems holding very large amounts of complex data. Databases meet many requirements of the hypermedium: persistent data management, large volumes, data modelling, multi-level architecture with abstractions ...

Object ive To construct a data base (the "Penn Treebank') of written and transcribed spoken American English annotated with detailed grammatical structure. This data base will serve as a national resource, providing training material for a wide variety of approaches to automatic language acquisition, a rei~rence standard for the rigorous evaluation of some components of natural language underst...

Partitioning a multi-dimensional data set (array) into rectangular regions subject to some constraints (error measures) is an important problem arising from applications in parallel computing, databases, VLSI design, and so on. In this paper, we consider two most common types of partitioning used in practice: the Arbitrary partitioning and (p × p) partitioning, and study their relationships und...

Abstract Software Testing is an established activity in the software development process to ensure and improve quality of a software. Consequently, there exists wide range literature, popular information, even multiple ISO standards covering this topic. However, we found that testing very large database management systems (DBMS) requires special adaptations generally available guidance for solv...

T he controllability properties of thermally coupled distillation sequences for the separation of ternary mixtures are compared with those of the conventional direct and indirect sequences. Closed loop responses to set point changes were performed, and controllers were tuned to minimize their ISE values. The results indicate that the integrated systems exhibit better control properties than seq...