Search results
Results From The WOW.Com Content Network
Negative feedback: If the signal feedback is out of phase by 180° with respect to the input signal, the feedback is called negative feedback. As an example of negative feedback, the diagram might represent a cruise control system in a car that matches a target speed such as the speed limit. The controlled system is the car; its input includes ...
A number of examples of positive feedback systems may be found in physiology. One example is the onset of contractions in childbirth, known as the Ferguson reflex. When a contraction occurs, the hormone oxytocin causes a nerve stimulus, which stimulates the hypothalamus to produce more oxytocin, which increases uterine contractions.
An example of positive feedback is when a microphone picks up the sound that it is producing through a speaker, which is then played through the speaker, and so on. In addition to feedback, cybernetics is concerned with other forms of circular processes including: feedforward , recursion , and reflexivity .
Audio feedback, the "howl" sometimes heard in microphone or guitar amplification systems; Video feedback, the optical equivalent of audio feedback, caused when a camera films the image it is producing; Positive feedback, a feedback system that responds to perturbation in the same direction as the perturbation
A simple negative feedback system is descriptive, for example, of some electronic amplifiers. The feedback is negative if the loop gain AB is negative.. Negative feedback (or balancing feedback) occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by ...
Feedback can also be recorded as a score, such as a percentage, a letter grade, or an achievement level defined by a specific reference. Grades can be based on the teacher's overall impression of the work, but assessment based on explicit criteria is increasingly common. An example of such holistic assessment is a rubric. A typical rubric is a ...
Relevance feedback is a feature of some information retrieval systems. The idea behind relevance feedback is to take the results that are initially returned from a given query, to gather user feedback, and to use information about whether or not those results are relevant to perform a new query. We can usefully distinguish between three types ...
Audio feedback (also known as acoustic feedback, simply as feedback) is a positive feedback situation that may occur when an acoustic path exists between an audio output (for example, a loudspeaker) and its audio input (for example, a microphone or guitar pickup).