Cellular automata (CA) are important as prototypical, spatially extended, discrete dynamical systems. Because the problem of forecasting dynamic behavior of CA is undecidable, various parameter-based approximations have been developed to address the problem. Out of the analysis of the most important parameters available to this end we proposed some guidelines that should be followed when defining a parameter of that kind. Based upon the guidelines, new parameters were proposed and a set of five parameters was selected; two of them were drawn from the literature and three are new ones, defined here. This article presents all of them and makes their qualities evident. Then, two results are described, related to the use of the parameter set in the Elementary Rule Space: a phase transition diagram, and some general heuristics for forecasting the dynamics of one-dimensional CA. Finally, as an example of the application of the selected parameters in high cardinality spaces, results are presented from experiments involving the evolution of radius-3 CA in the Density Classification Task, and radius-2 CA in the Synchronization Task.
A chaotic oscillatory correlation network for scene segmentation is presented. It is a two-dimensional array with locally coupled chaotic elements. It offers a mechanism to escape from the synchrony–desynchrony dilemma. As a result, this model has unbounded capacity of segmentation. Chaotic dynamics and chaotic synchronization in the model are analyzed. Desynchronization property is guaranteed by the definition of chaos. Computer simulations confirm the theoretical prediction.
An expert system for the air traffic flow management (ATFM) problem is presented. Two main prototypes have been constructed, one for timetable rescheduling that attempts to modify airline timetables to smooth traffic peaks at airports during rush-hours and another for centrulizedflow control that works to forecast the place, time and magnitude of the congestion and to propose mitigative actions. Simulations for the Brazilian ATFM, including the principal 14 airports, show the potential usefulness of the expert system.
As paradigmatic complex systems, various studies have been done in the context of one-dimensional cellular automata (CA) on the definition of parameters directly obtained from their transition rule, aiming at the help they might provide to forecasting CA dynamic behavior. Out of the analysis of the most important parameters available for this end, as well as others evaluated by us, a set of guidelines is proposed that should be followed when defining a parameter of that kind. Based upon the guidelines, a critique of those parameters is made, which leads to a set of five that jointly provide a good forecasting set; two of them were drawn from the literature and three are new ones defined according to the guidelines. By using them as a heuristic in the evolutionary search for CA of a predefined computational behavior, good results have been obtained, exemplified herein by the evolutionary search for CA that perform the Synchronization Task. ᭧ 2001 John Wiley & Sons, Inc. SUMMARY C ellular automata (CA) are discrete complex systems which possess both a dynamic and a computational nature. In either case, based only upon their definition, it is not possible to forecast either their dynamic behavior, or the computation they will perform when running. However, it is possible to derive static parameters from their definition, which can then be used to estimate their dynamic behavior. This has already been done in the literature, but here we significantly extend previous efforts, by means of an analysis of the available parameters and the definition of new ones, which is achieved through the identification of a set of guidelines those parameters should abide by. The effectiveness of these guidelines are demonstrated, by using a set of five parameters drawn from them, as aids in the design of CA that should perform a predefined computational task; in the current case, such an aid represents guiding an evolutionary search for CA that perform a well-known task for one-dimensional CA, the so-called Synchronization Task.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.