Abstract : This special issue contains four papers presented during the
workshop, ‘‘18th International Workshop on Cellular
Automata and Discrete Complex Systems’’ (Automata
2012), held in La Marana, Corsica island (France) in the
period September 19–21th, 2012.
The aim of this workshop is to establish and maintain a
permanent, international, multidisciplinary forum for the
collaboration of researchers in the field of Cellular Automata
(CA) and Discrete Complex Systems (DCS), provide
a platform for presenting and discussing new ideas and
results, and support the development of theory and applications
of CA and DCS.
Typical, but not exclusive, topics of the workshop are:
dynamics aspects, algorithmic, computational and complexity
issues, emergent properties, formal language processing,
models of parallelism and distributed systems,
phenomenological descriptions, scientific modeling and
After an additional review process, four papers were
selected and included in this special issue. They are now
presented in an extended and improved form with respect
to the already refereed workshop version that appeared in
the proceedings of Automata 2012.
The paper ‘‘Computation of Functions on n Bits by
Asynchronous Clocking Cellular Automata’’ by Michael
Vielhaber aims at proving that different functions on binary
vectors can be computed by changing the updating scheme
from a fully synchronous to an asynchronous one on some
fixed CA local rule.
In their paper ‘‘Solving the Parity Problem in One–
Dimensional Cellular Automata’’, Heather Betel, Pedro
P. B. de Oliveira, and Paola Flocchini deal with the parity
problem in one–dimensional cellular automata (CA): a CA
local rule solves the parity problem if, starting from any
initial configuration, the CA converges to the 0–configuration
(resp., the 1–configuration) if and only if the initial
configuration contains an even number of 1s (resp., an odd
number of 1s). In particular, authors focus on the neighborhood
size of CA rules solving the problem.
Murillo G. Carneiro and Gina M. B. Oliveira present in
the paper ‘‘Synchronous Cellular Automata-Based Scheduler
initialized by Heuristic and modeled by a Pseudolinear
neighborhood’’ two approaches based on CA to the
task scheduling problem in multiprocessor systems.
The implementation of cellular automata on processor
arrays is considered by Jean-Vivien Millo and Robert
de Simone in the paper ‘‘Explicit routing schemes for
implementation of cellular automata on processor arrays’’.
They deal with the trade-offs between the generality of the
CA neighborhood and the limited expressive power provided
by physical platforms. This is an extremely hot topic
which will help in turning CA towards real extended
We would like to warmly thank the authors for their
work and effort which made this special issue possible.
Special thanks go to all referees for their valuable contributions
both during the selection and the final review
process. Finally, we also want to thank Professor Grzegorz
Rozenberg for offering us the opportunity to publish this
special issue in Natural Computing.