Centralised training, however, is costly, sometimes unavailable for specific industries and, to be effective, requires reinforcement at work.
They have tended to require continual reinforcement, guidance and creative stimulation.
Young birds require reinforcement from adults in order to finalize their songs.
But the problem is that, even after you've tricked both sides into seeing one another as different kinds of 'Us,' the perception requires constant reinforcement.
This may hold evolutionary significance since regions of contrast are information rich requiring reinforcement and the allocation of attention.
All Indian music seems to be amplified these days, and to require such reinforcement.
There are, however, certain areas that require reinforcement.
Important aspects here, requiring independent reinforcement, are qualifications and basic and further training.
The original breech of the old 38cm gun did not require modification or reinforcement.
The church required seismic reinforcement after the 1989 Loma Prieta earthquake.