In the beginning of adaption, the big

error makes the big step size and fast convergence rate with

the adaptive process going on, errors are reduced gradually,

step size is also decreased. When adaption reached

steady-state phase, the error is very small, and close to zero,

step size is zero approximately-In the beginning of adaption, the big

error makes the big step size and fast convergence rate　with

the adaptive process going on, errors are reduced gradually,

step size is also decreased. When adaption reached

steady-state phase, the error is very small, and close to zero,

step size is zero approximately