GUEST LECTURE:
		Matching Local Text Structure

BY: 		Professor Frank Wm. Tompa, Department of Computer
Science,
		University of Waterloo, Canada

ON:		Tuesday, April 20, 1999, at 14.15 - 16.00

AT:		University of Helsinki, Department of Computer Science
		Helsinki, Teollisuuskatu 23, room A414


ABSTRACT:

XML documents encode the structure of text components through markup.
Although grammars provide a mechanism to abstract the structure, they
must be quite intricate if they are to describe the relationships among
components in well-written documents.  Luckily, data can be extracted
efficiently from marked up text even if the relationships do not
necessarily conform to a grammar.

Waterloo's Text/Relational Database Management System provides operators
to match the contents of texts described in terms of trees that are
dynamically superimposed over the text.  Furthermore, tabular views can
also be dynamically imposed on sections of texts to provide simple
access to lists of related data, such as found particularly in catalogs
and bibliographies. Thus, even though a text does not have a regular and
consistent hierarchical or tabular structure, local regularity can be
temporarily overlaid in order to form a response to a query. The talk
will summarize operators that allow applications to identify, extract,
and manipulate interesting components from structured text.


RESUME:

Frank Tompa is a Professor in the Department of Computer Science at 
the University of Waterloo, a member of Waterloo's Database Research
Group, and Director of the UW Centre for the New Oxford English
Dictionary 
and Text Research.  His teaching and research interests include data 
structure design, relational database design, and the design of text 
management systems suitable for maintaining large reference texts 
and large text collections.


WELCOME!!

Pekka Kilpelainen, University of Helsinki, Dept. of Computer Science
      Email: Pekka.Kilpelainen@cs.helsinki.fi 
      phone: +358 9 7084 4227, fax: +358 9 7084 4441
      http://www.cs.helsinki.fi/~kilpelai