Download DAC Distributed Adaptive Control: Tutorial on Foraging

Tutorial 4: DAC Contextual Layer
The contextual layer module implements the mechanisms for storing and recalling
information from memory, as explained in the chapter on DAC5. It has seven
parameters that can be set by the user (Fig. 2):
height: number of sequences (NL) that can be stored in the LTM.
width: maximum number of segments (NS) that can form a sequence in
the STM and in the LTM.
discrepancy threshold: this parameter determines when the contextual layer
will be activated, i. e. when the distance between the current CS prototype
generated by the adaptive layer and the currentcs is below the discrepancy
threshold, the contextual layer is enabled.
selection threshold: only the collectors that have an activity above this selection threshold are selected and compete in an E%-WTA.
%-WTA: the percentage value that defines the WTA competition, i.e. only if
the activity of the collector is equal or greater than the %-WTA of the maximum
collector’s activity it is selected. Higher value of %-WTA means that less
collectors are selected and vice versa.
trigger reset: value that the trigger of a segment following a selected one gets
so that it has more probability of being selected later on.
trigger decay: defines how rapidly the trigger value decays back to its default
value of 1 so that with time the segment does not have more priority over the
others anymore.
Figure 2.
Properties panel of the contextual layer module. The user can set the
parameters that will be used by the contextual layer in the acquisition
and retrieval of information.
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