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    ELECTRONIC NEWSLETTER ON  REASONING ABOUT ACTIONS AND CHANGE        
Issue 99019             Editor: Erik Sandewall             21.7.1999
         Back issues available at http://www.etaij.org/rac/
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                    *********  TODAY  *********

Today we advertise an article submitted by Michael Thielscher, 
addressing planning in hybrid domains with both discrete and continuous
change. This is the first example of an ETAI article that builds on the
previously published reference articles for its definitions, whereby
the length of the article has been reduced considerably.


              *********  ETAI PUBLICATIONS  *********

               ---  RECEIVED REFERENCE ARTICLES  ---

        ========================================================
        |  AUTHOR: Michael Thielscher
        |  TITLE:  Fluent Calculus Planning with Continuous Change
        |  PAPER:  http://www.ida.liu.se/ext/epa/cis/1999/011/tcover.html
        |          (temporary location awaiting E-press publication)
        |  REVIEW: http://www.ida.liu.se/ext/etai/ra/rac/020/
        ========================================================

                             ABSTRACT 

Green's classical definition of planning by deduction has recently
been generalized to hybrid domains, which involve both discrete and
continuous change. We show that this generalization is unsuited for
planning under incomplete information. An improved theory is developed
on the basis of the novel concept of a situation tree with trajectories
and using the predicate formalism of the Fluent Calculus.


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