Self-Organization: A Common Principle of Information Processing by Distributed Dynamic Systems - Molecular Computing: Origins and Promises - page 182

Fig. 6.12 Scheme of the
dynamics of the reaction-
diffusion processor
influencing them locally arise—the splitting of the waves, their annihilation, and
formation of complex autowave structures.
As noted above, in Chap. 5 , intense light radiation transfers the medium into an
inert state. This creates a number of additional options for constructing information
processing systems. By constantly projecting on the medium a given distribution of
the intensity of the radiation of high intensity, one can obtain in the medium areas of
specified shape and size. The evolution of the medium will occur only in those
areas. In this case the required dynamic regime can be selected individually in each
area by defining the degree of its illumination (Fig. 6.11 ). This technique—the
selection of the working area of the medium by intense light radiation—was used,
for example, to find the shortest path in the maze and for the formation of a
“chemical diode,” covered in detail in Chap. 5 .
Let two spatial distributions of the reaction-diffusion medium, operating in
different dynamic regimes, be separated by a thin partition permeable to some
components of the medium. In this case a spontaneous process of interaction
between media arises, which leads to a change in their modes of operation. This
effect can be used to create multilevel devices capable of performing complex logic
functions.
Thus, the reaction-diffusion processor is a complex dynamic system, in which
from the chemical medium of variable and even of the same composition sub-
systems can be formed that perform operations of different nature. Their formation
is due to the processes of self-organization of the medium, initiated by control
stimuli. Diffusion interactions can combine separate subsystems, linking them into
a single information-logical device.