  This work investigates the use of two-stage clustering methods. Four
techniques were proposed: SOMK, SOMAK, ASCAK and SOINAK. SOMK is composed of a
SOM (Self-Organizing Maps) followed by the K-means algorithm, SOMAK is a
combination of SOM followed by the Ant K-means (AK) algorithm, ASCAK is
composed by the ASCA (Ant System-based Clustering Algorithm) and AK algorithms,
SOINAK is composed by the Self-Organizing Incremental Neural Network (SOINN)
and AK. SOINAK presented a better performance among the four proposed
techniques when applied to pattern recognition problems.
