perceptibility การใช้

Its main function is to improve perceptibility of traffic signals for pedestrians.
Security was tight around Mal?due to the obvious perceptibility of such a demonstration to mark this anniversary.
Obviously, perceptibility of information does not necessarily correspond with its actual relevance to the learning task to be performed.
The article says they are " imperceptible ", but I'd argue that their perceptibility depends on scale how close in do you care?
Vocal expressions of anger and sadness are perceived most easily, fear and happiness are only moderately well-perceived, and disgust has low perceptibility.