% Sample LaTeX file for creating a paper in the Morgan Kaufmannn two 
% column, 8 1/2 by 11 inch proceedings format. 

 
\documentstyle[psfig,html]{article} 
\input{epsf}

\newcommand{\ie}{{\em i.e.}}
\newcommand{\eg}{{\em e.g.}}
\newcommand{\etal}{{\em et al}}
\newcommand{\etc}{{\em etc}}
\newcommand{\mquery}{{CoGeo}}
\newcommand{\cobase}{{CoBase}}


\title{The Design and Implementation of CoBase}

\author{W. W. Chu, M. A. Merzbacher, L. Berkovich \\
Computer Science Department \\
University of California at Los Angeles \\
}

\begin{document}

\maketitle


\begin{abstract}
CoBase, a cooperative database, is a new type
of distributed database that integrates knowledge base
technology with database systems to provide cooperative
(approximate and conceptual) query answering.  Based on the
database schema
and application characteristics, data are organized into conceptual
(type abstraction) hierarchies.  The higher levels of
the hierarchy provide a more abstract data representation
than the lower levels.  Generalization (moving up in the hierarchy),
specialization (moving down in the hierarchy) and association
(moving between hierarchies) are the three key operations in
deriving cooperative query answers.

Relaxation in CoBase can also be specified explicitly in the query
by the user or calling program through cooperative operators.
We have extended SQL to CSQL by adding cooperative primitives.
We describe the CoBase software implementation, including an
inter--module data protocol that provides a uniform module interface.
This modular approach provides flexibility in adding new relaxation
modules and simplifies software maintenance.

CoBase uses LOOM as its knowledge representation
and inference system and
supports relational data bases (e.g. Oracle and Sybase).
We have demonstrated the feasibility
and functionality of CoBase on top of a Transportation Database.
The CoBase methodology has also been adopted in the multi-media
medical distributed database project at UCLA, which
provides approximate query answers to medical queries.
\end{abstract}

{\em Index Terms}: 
Knowledge Representation,
Type Hierarchy,
Type Abstraction Hierarchy,
Query Language,
Query Rewrite,
Cooperative Query Answering,
Semantic Distance,
Relaxation Control

\htmladdnormallink{View the Paper (requiring a postscript viewer)}
{http://burton.cs.ucla.edu/tech-docs/sigmod.ps}

\end{document} 

