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From: steve@lapu (Steve Gregory)
Subject: Re: TSP with Prolog
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References: <1994Nov23.230736@mines.u-nancy.fr> <THOMASL.94Nov24162059@arnold.csd.uu.se> <3bf8qo$pjb@beta.qmw.ac.uk>
Date: Thu, 1 Dec 1994 15:56:11 GMT
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Matthew Huntbach (mmh@dcs.qmw.ac.uk) wrote:
: Thomas Lindgren (thomasl@arnold.csd.uu.se) wrote:
: : In article <1994Nov23.230736@mines.u-nancy.fr> raufastp@mines.u-nancy.fr (Pierre Raufast) writes:
: :    Does anyone know how to program the Travelling Salesman Problem with
: :    Prolog?
: : ... You may want to use branch-and-bound in that case:
: : pass around a global minimum and cut off search when the current path
: : is longer than the minimum; update the minimum when a better solution
: : is found.
: For comparison, I discuss the approach in an and-parallel language in my
: paper "Parallel Branch and Bound Search in Parlog" in International
: Journal of Parallel Programming 20, 4 pp.299-314, 1991. I also have a version
: which will appear in a paper next year which has local minima to avoid the
: bottleneck effect of many processes accessing a single global minimum.
: Matthew Huntbach

A similar approach to Matthew's was implemented and applied to the
Travelling Salesman Problem; see my paper "Experiments with speculative
parallelism in Parlog" in ILPS93.  A TR version of this paper, and a KL1
version of the actual code, can be found at
http://star.cs.bris.ac.uk/Interests/spec.html.

steve gregory
