threshold

threshold

The point at which a signal (voltage, current, etc.) is perceived as valid.

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threshold

1. Psychol the strength at which a stimulus is just perceived

2. 

a. the minimum intensity or value of a signal, etc., that will produce a response or specified effect

b. (as modifier): a threshold current

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threshold [′thresh‚hōld]

(building construction)

A piece of stone, wood, or metal that lies under an outside door.

(electronics)

In a modulation system, the smallest value of carrier-to-noise ratio at the input to the demodulator for all values above which a small percentage change in the input carrier-to-noise ratio produces a substantially equal or smaller percentage change in the output signal-to-noise ratio.

(engineering)

The least value of a current, voltage, or other quantity that produces the minimum detectable response in an instrument or system.

(geology)

riegel

(mathematics)

A logic operator such that, ifP, Q, R, S,… are statements, then the threshold will be true if at leastNstatements are true, false otherwise.

(physics)

The minimum level of some input quantity needed for some process to take place, such as a threshold energy for a reaction, or the minimum level of pumping at which a laser can go into self-excited oscillation.

(physiology)

The minimum level of a stimulus that will evoke a response in an irritable tissue.