Preprints

[Gregory Kohring]

The following preprint is currently available.
                                       -- Greg Kohring

        Performance Enhancement of Willshaw Type
        Networks through the use of Limit Cycles

                    G.A. Kohring
               HLRZ an der KFA Julich
         (Supercomputing Center at the KFA Julich)

Simulation results of a Willshaw type model for storing sparsely
coded patterns are presented. It is suggested that random patterns can
be stored in Willshaw type models by transforming them into a set of
sparsely coded patterns and retrieving this set as a limit cycle.
In this way, the number of steps needed to recall a pattern will be
a function of the amount of information the pattern contains.
A general algorithm for simulating neural networks
with sparsely coded patterns is also discussed, and, on a fully
connected network of N=36 864  neurons (1.4 billion couplings),
it is shown to achieve effective updating speeds as high as
160 billion coupling evaluations per second on one Cray-YMP processor.

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Additionally, the following short review article is also available.
It is aimed at graduate students in computational physics who need an
overview of the neural network literature from a computational sciences
viewpoint, as well as some simple programming hints in order to get
started with their neural network studies. It will shortly
appear in World Scientific's Internationl Journal of Modern Physics C:
Compuational Physics.


         LARGE SCALE NEURAL NETWORK SIMULATIONS

                    G.A. Kohring
               HLRZ an der KFA Julich
         (Supercomputing Center at the KFA Julich)

The current state of large scale, numerical simulations of neural
networks is reviewed. Hardware and software improvements make it likely
that biological size networks, i.e., networks with more than $10^{10}$
couplings, can be simulated in the near future. Sample programs for the
efficient simulation of a few simple models are presented as an aid to
researchers just entering the field.


Send Correspondence and request for preprints to:

G.A. Kohring
HLRZ an der KFA Julich
Postfach 1913
D-5170 Julich, West Germany

e-mail: hkf218 at djukfa11.bitnet

Address after September 1, 1990:

Institut fur Theoretische Physik
Universitat zu Koln
D-5000 Koln  41, West Germany