Positive feedback
2019-01-23
https://gyazo.com/03f405e98bc95b76c2bb4b9478275ec7
It's getting bigger and bigger, and the rate of increase is accelerating.
[Positive feedback
Not to be confused with "positive feedback" in communication.
Right figure, cases that become smaller and smaller, and the rate of decrease accelerates, are also "positive feedback" cases
Often misunderstood because of the mood of the word "positive" https://gyazo.com/db33a4fd706b1f0f7fe883f73726586d
When a value deviates from a reference value, a force is applied that magnifies the deviation (= positive, in the same direction as the direction of the deviation)
Therefore, both "accelerating in the direction of increasing" and "accelerating in the direction of decreasing" are positive feedback.
https://gyazo.com/47b5c3920983a64495cd9dc8c6f9b9cf
Conversely, when a deviation from the reference value occurs, a force is applied in the direction to reduce the deviation.
So, after a deviation due to disturbance, etc., the deviation decreases and returns to the original standard value.
That is, negative feedback brings [stability
Some people make the mistake of thinking it's bad because of the word negative, but it doesn't correspond to good or evil. The sound that comes in through the microphone is magnified and comes out through the speakers, which are then picked up again by the microphone, developing into a loud sound.
Everything that is stable around us involves some form of negative feedback.
For example, body temperature
When the body temperature rises, sweat is produced on the body surface to cool down by vaporization heat to lower the temperature.
When the body temperature drops, the muscles quiver to produce heat and raise the temperature
relevance
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