2.2 Projection direction optimization
For complex nonlinear and high-dimension PPDC
model problem, the determination of optimal
projection direction is a high-dimensional constrained
optimization problem. The commonly used intelligent
optimization algorithms are SA algorithm[10], GA[11],
PSO[12], and Ant Colony (AC) algorithm[13].
These methods can find the best projection direction,
but have excessive structural complexity, or fall easily
into local optima. Thus, using intelligent algorithms to
solve optimization problems is possible only with some
modifications and improvements.