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1045:, most parameters must stay under control within a narrow range around a certain optimal level under certain environmental conditions. The deviation of the optimal value of the controlled parameter can result from the changes in internal and external environments. A change of some of the environmental conditions may also require change of that range to change for the system to function. The value of the parameter to maintain is recorded by a reception system and conveyed to a regulation module via an information channel. An example of this is
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feedback responses in cells, which alter gene expression, and change the groups of molecules expressed and secreted, including molecules that induce diverse cells to cooperate and restore tissue structure and function. This type of feedback is important because it enables coordination of immune responses and recovery from infections and injuries. During cancer, key elements of this feedback fail. This disrupts tissue function and immunity.
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709:. The error signal is the difference of the speed as measured by the speedometer from the target speed (set point). The controller interprets the speed to adjust the accelerator, commanding the fuel flow to the engine (the effector). The resulting change in engine torque, the feedback, combines with the torque exerted by the change of road grade to reduce the error in speed, minimising the changing slope.
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1158:. Release of hormones then may cause more of those hormones to be released, causing a positive feedback loop. This cycle is also found in certain behaviour. For example, "shame loops" occur in people who blush easily. When they realize that they are blushing, they become even more embarrassed, which leads to further blushing, and so on.
2572:"However, after scrutinizing the statistical properties of the structural equations, the members of the committee assured themselves that it is possible to have a significant positive feedback loop when using standardized scores, and a negative loop when using real scores." Ralph L. Levine, Hiram E. Fitzgerald.
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When there are only two parts joined so that each affects the other, the properties of the feedback give important and useful information about the properties of the whole. But when the parts rise to even as few as four, if every one affects the other three, then twenty circuits can be traced through
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Friis and Jensen had made the same distinction Black used between "positive feed-back" and "negative feed-back", based not on the sign of the feedback itself but rather on its effect on the amplifier's gain. In contrast, Nyquist and Bode, when they built on Black's work, referred to negative feedback
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Focusing on uses in management theory, Ramaprasad (1983) defines feedback generally as "...information about the gap between the actual level and the reference level of a system parameter" that is used to "alter the gap in some way". He emphasizes that the information by itself is not feedback unless
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Normal tissue integrity is preserved by feedback interactions between diverse cell types mediated by adhesion molecules and secreted molecules that act as mediators; failure of key feedback mechanisms in cancer disrupts tissue function. In an injured or infected tissue, inflammatory mediators elicit
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that has two stable states and can be used to store state information. They typically constructed using feedback that crosses over between two arms of the circuit, to provide the circuit with a state. The circuit can be made to change state by signals applied to one or more control inputs and will
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into a circuit. This can cause the circuit to ignore small signals and respond only to large ones. It is sometimes used to eliminate noise from a digital signal. Under some circumstances, positive feedback may cause a device to latch, i.e., to reach a condition in which the output is locked to its
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object to the mathematician's definition, pointing out that this would force them to say that feedback was present in the ordinary pendulum ... between its position and its momentum—a "feedback" that, from the practical point of view, is somewhat mystical. To this the mathematician retorts that if
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Feedback loops provide generic mechanisms for controlling the running, maintenance, and evolution of software and computing systems. Feedback-loops are important models in the engineering of adaptive software, as they define the behaviour of the interactions among the control elements over the
637:(1956), mathematicians and theorists interested in the principles of feedback mechanisms prefer the definition of "circularity of action", which keeps the theory simple and consistent. For those with more practical aims, feedback should be a deliberate effect via some more tangible connection.
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Simple causal reasoning about a feedback system is difficult because the first system influences the second and second system influences the first, leading to a circular argument. This makes reasoning based upon cause and effect tricky, and it is necessary to analyze the system as a whole. As
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and accuracy of a system by correcting or reducing the influence of unwanted changes. This scheme can fail if the input changes faster than the system can respond to it. When this happens, the lag in arrival of the correcting signal can result in over-correction, causing the output to
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Physical systems present feedback through the mutual interactions of its parts. Feedback is also relevant for the regulation of experimental conditions, noise reduction, and signal control. The thermodynamics of feedback-controlled systems has intrigued physicist since the
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In general, feedback systems can have many signals fed back and the feedback loop frequently contain mixtures of positive and negative feedback where positive and negative feedback can dominate at different frequencies or different points in the state space of a system.
548:. This device illustrated the principle of feedback: a low water level opens the valve, the rising water then provides feedback into the system, closing the valve when the required level is reached. This then reoccurs in a circular fashion as the water level fluctuates.
1546:, but that term also is used to indicate other phase separations, as in "90° out of phase". Negative feedback can be used to correct output errors or to desensitize a system to unwanted fluctuations. In feedback amplifiers, this correction is generally for waveform
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system in a car that matches a target speed such as the speed limit. The controlled system is the car; its input includes the combined torque from the engine and from the changing slope of the road (the disturbance). The car's speed (status) is measured by a
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Using this terminology, a latch is level-sensitive, whereas a flip-flop is edge-sensitive. That is, when a latch is enabled it becomes transparent, while a flip flop's output only changes on a single type (positive going or negative going) of clock edge.
1771:, the output and next state depend not only on its current input, but also on its current state (and hence, previous inputs). It can also be used for counting of pulses, and for synchronizing variably-timed input signals to some reference timing signal.
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Feedback is used extensively in digital systems. For example, binary counters and similar devices employ feedback where the current state and inputs are used to calculate a new state which is then fed back and clocked back into the device to update it.
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By using feedback properties, the behavior of a system can be altered to meet the needs of an application; systems can be made stable, responsive or held constant. It is shown that dynamical systems with a feedback experience an adaptation to the
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adaptation process, to guarantee system properties at run-time. Feedback loops and foundations of control theory have been successfully applied to computing systems. In particular, they have been applied to the development of products such as
1811:(MAPE, monitor analyze plan execute) loop proposed by researchers of IBM is another valuable contribution to the application of feedback loops to the control of dynamic properties and the design and evolution of autonomic software systems.
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While simple systems can sometimes be described as one or the other type, many systems with feedback loops cannot be shoehorned into either type, and this is especially true when multiple loops are present.
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Positive feedback occurs when the fed-back signal is in phase with the input signal. Under certain gain conditions, positive feedback reinforces the input signal to the point where the output of the device
578:, and were used for pumping water – an application that could tolerate variations in the working speed, but the use of steam engines for other applications called for more precise control of the speed.
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The term bipolar feedback has been coined to refer to biological systems where positive and negative feedback systems can interact, the output of one affecting the input of another, and vice versa.
1599:. If a microphone is in front of a loudspeaker that it is connected to, sound that the microphone picks up comes out of the speaker, and is picked up by the microphone and re-amplified. If the
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The two definitions may be confusing, like when an incentive (reward) is used to boost poor performance (narrow a gap). Referring to definition 1, some authors use alternative terms, replacing
1118:. These feedback loops may be positive (as in the case of the coupling between a sugar molecule and the proteins that import sugar into a bacterial cell), or negative (as is often the case in
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965:(black) within a continuously colored environment is plotted by repeatedly feeding back values through a simple equation and recording the points on the imaginary plane that fail to diverge.
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On a larger scale, feedback can have a stabilizing effect on animal populations even when profoundly affected by external changes, although time lags in feedback response can give rise to
623:), but would also cause the audion to howl or sing. This action of feeding back of the signal from output to input gave rise to the use of the term "feedback" as a distinct word by 1920.
1778:(synchronous or edge-triggered). Although the term flip-flop has historically referred generically to both simple and clocked circuits, in modern usage it is common to reserve the term
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Negative feedback occurs when the fed-back output signal has a relative phase of 180° with respect to the input signal (upside down). This situation is sometimes referred to as being
1290:(1572-1633) built thermostats (c1620) to control the temperature of chicken incubators and chemical furnaces. In 1745, the windmill was improved by blacksmith Edmund Lee, who added a
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The climate system is characterized by strong positive and negative feedback loops between processes that affect the state of the atmosphere, ocean, and land. A simple example is the
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Korneev, KV; Atretkhany, KN; Drutskaya, MS; Grivennikov, SI; Kuprash, DV; Nedospasov, SA (January 2017). "TLR-signaling and proinflammatory cytokines as drivers of tumorigenesis".
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2244:"When the journal or spindle is cut ... and the carriage is about to feed back by a change of the sectional nut or burr upon the screw-shafts, the operator seizes the handle..."
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rather than feedback. Yet even within a single discipline an example of feedback can be called either positive or negative, depending on how values are measured or referenced.
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Mechanisms of feedback were first elucidated in bacteria, where a nutrient elicits changes in some of their metabolic functions. Feedback is also central to the operations of
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provided by
Webster, feedback in business is the transmission of evaluative or corrective information about an action, event, or process to the original or controlling source.
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H. Giese; Y. Brun; J. D. M. Serugendo; C. Gacek; H. Kienle; H. Müller; M. Pezzè; M. Shaw (2009). "Engineering self-adaptive and self-managing systems". Springer-Verlag.
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as that with the sign reversed. Black had trouble convincing others of the utility of his invention in part because confusion existed over basic matters of definition.
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The parameters of a system ... may vary... The primary advantage of using feedback in control systems is to reduce the system's sensitivity to parameter variations.
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Vlahopoulos, SA; Cen, O; Hengen, N; Agan, J; Moschovi, M; Critselis, E; Adamaki, M; Bacopoulou, F; Copland, JA; Boldogh, I; Karin, M; Chrousos, GP (20 June 2015).
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feedback is to be considered present only when there is an actual wire or nerve to represent it, then the theory becomes chaotic and riddled with irrelevancies.
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H. A. Müller; H. M. Kienle & U. Stege (2009). "Autonomic computing: Now you see it, now you don't—design and evolution of autonomic software systems".
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the forward path may not be strictly unilateral, the feedback path is usually bilateral, and the input and output coupling networks are often complicated.
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Dijk, E., Cremer, D.D., Mulder, L.B., and
Stouten, J. "How Do We React to Feedback in Social Dilemmas?" In Biel, Eek, Garling & Gustafsson, (eds.),
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Herold, David M., and Martin M. Greller. "Research Notes. FEEDBACK THE DEFINITION OF A CONSTRUCT." Academy of management
Journal 20.1 (1977): 142-147.
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The terms "positive" and "negative" were first applied to feedback prior to WWII. The idea of positive feedback already existed in the 1920s when the
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Negative feedback: If the signal feedback is out of phase by 180° with respect to the input signal, the feedback is called negative feedback.
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signal. They are widely used in many electronic devices. Common examples of signals generated by oscillators include signals broadcast by
1136:, feedback serves as regulation of activity of an enzyme by its direct product(s) or downstream metabolite(s) in the metabolic pathway (see
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effects. A negative feedback loop is one that tends to slow down a process, whereas the positive feedback loop tends to accelerate it. The
600:, in the sense of returning to an earlier position in a mechanical process, was in use in the US by the 1860s, and in 1909, Nobel laureate
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in non-linear systems, while others have much more predictable behaviors, such as those that are used to make and design digital systems.
619:) had discovered that deliberately coupling part of the output signal back to the input circuit would boost the amplification (through
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Positive feedback: If the signal feedback from output is in phase with the input signal, the feedback is called positive feedback.
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wrote a famous paper, "On governors", that is widely considered a classic in feedback control theory. This was a landmark paper on
2228:"Heretofore ... it has been necessary to reverse the motion of the rollers, thus causing the material to travel or feed back, ..."
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or "hunt". While often an unwanted consequence of system behaviour, this effect is used deliberately in electronic oscillators.
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1506:. A feedback loop is created when all or some portion of the output is fed back to the input. A device is said to be operating
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was one of the largest steamships of its time and employed a steam powered rudder with feedback mechanism designed in 1866 by
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in
Britain by the 18th century, but it was not at that time recognized as a universal abstraction and so did not have a name.
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1439:. Electronic feedback systems are also very commonly used to control mechanical, thermal and other physical processes.
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are part of a social feedback system, when an observed action is "mirrored" by the brain—like a self-performed action.
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1218:, and so forth. In the context of control theory, "feedback" is traditionally assumed to specify "negative feedback".
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1965: – Academic discipline studying the relationship between computer systems and their users, which also includes:
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CS Holling. "Resilience and stability of ecological systems". Annual Review of
Ecology and Systematics 4:1-23. 1973
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Biological systems contain many types of regulatory circuits, both positive and negative. As in other contexts,
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them; and knowing the properties of all the twenty circuits does not give complete information about the system.
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When two or more amplifiers are cross-coupled using positive feedback, complex behaviors can be created. These
724:'s classic 1934 paper first details the use of negative feedback in electronic amplifiers. According to Black:
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Friis, H.T., and A.G.Jensen. "High
Frequency Amplifiers" Bell System Technical Journal 3 (April 1924):181–205.
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Over the years there has been some dispute as to the best definition of feedback. According to cybernetician
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was made. Friis and Jensen (1924) described this circuit in a set of electronic amplifiers as a case where
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Maintaining a desired system performance despite disturbance using negative feedback to reduce system error
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There are two main types of electronic oscillator: the linear or harmonic oscillator and the nonlinear or
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monostable circuits, which can be pushed into a state, and will return to the stable state after some time
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into itself. The notion of cause-and-effect has to be handled carefully when applied to feedback systems:
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Internal combustion engines of the late 20th century employed mechanical feedback mechanisms such as the
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Latches and flip-flops are used as data storage elements. Such data storage can be used for storage of
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in 1873 to describe steam-powered steering systems. Hydraulic servos were later used to position guns.
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The terms positive and negative feedback are defined in different ways within different disciplines.
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Wotherspoon, T.; Hubler, A. (2009). "Adaptation to the edge of chaos with random-wavelet feedback".
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Self-regulating mechanisms have existed since antiquity, and the idea of feedback started to enter
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Thomas K. Connellan and Ron Zemke, "Sustaining Knock Your Socks Off
Service" AMACOM, 1 July 1993.
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for determining the stability of feedback systems. An easier method, but less general, is to use
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1979: – Loop delay that occurs when a video camera is pointed at its own playback video monitor
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Jacob, F; Monod, J (June 1961). "Genetic regulatory mechanisms in the synthesis of proteins".
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to adjust the distance between the bedstone and the runner stone (i.e., to adjust the load).
1154:, the body receives a stimulus from the environment or internally that causes the release of
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had described their concept through several kinds of "component motions" associated with the
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A feedback loop where all outputs of a process are available as causal inputs to that process
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respectively. And for definition 2, some authors promote describing the action or effect as
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from the 1940s onwards was centred around the study of circular causal feedback mechanisms.
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McGraw-Hill
Encyclopedia of Science and Technology, 10th Ed., Science Access online service
2853:"Dynamic aberrant NF-κB spurs tumorigenesis: A new model encompassing the microenvironment"
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Oscillators designed to produce a high-power AC output from a DC supply are usually called
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1871:. Aiming the camera at the display produces a complex video image based on the feedback.
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is largely controlled by positive and negative feedback, much of which is still unknown.
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between reference and actual values of a parameter or trait, based on whether the gap is
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designed his first centrifugal governor following a suggestion from his business partner
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2260:"...as far as possible the circuit has no feed-back into the system being investigated."
1971:– In human-computer interaction, low-key feedback is output that takes a background role
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bistable circuits, which have two stable states that the circuit can be switched between
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If the signal is inverted on its way round the control loop, the system is said to have
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is sufficient, howling or squealing at the maximum power of the amplifier is possible.
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maximum or minimum state. This fact is very widely used in digital electronics to make
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between its maximum and minimum possible states. Positive feedback may also introduce
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published a theoretical analysis of automatic ship steering in 1922 and described the
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in a disturbance or the amplitude of a wave or oscillation, from those that lead to a
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Positive feed-back increases the gain of the amplifier, negative feed-back reduces it.
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1953: – Control paradigm in which errors are measured before they can affect a system
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Feedback is extensively used in control theory, using a variety of methods including
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Between Human and
Machine : Feedback, Control, and Computing before Cybernetics
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3313:, Cambridge University Press (1980), Chapter 3, relating to operational amplifiers.
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Minorsky, Nicolas (1922). "Directional stability of automatically steered bodies".
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2008: – Cyclic structure that goes through several levels in a hierarchical system
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exclusively for discussing clocked circuits; the simple ones are commonly called
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level. A general expression for the gain of a negative feedback amplifier is the
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Process where information about current status is used to influence future status
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in contrast to negative feed-back action, which they mentioned only in passing.
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2287:. Stevenage; New York: Peregrinus for the Institution of Electrical Engineers.
1947: – Transdisciplinary field concerned with regulatory and purposive systems
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According to
Mindell (2002) confusion in the terms arose shortly after this:
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With mechanical devices, hunting can be severe enough to destroy the device.
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systems used in computers, communications, and many other types of systems.
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Introduction to Social Macrodynamics: Secular Cycles and Millennial Trends.
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JM Jay, "Improvement in Machines for Making the Spindles of Wagon-Axles",
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that alters the gap, based on whether it makes the recipient or observer
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3514:"...Sometimes the terms flip-flop and latch are used interchangeably..."
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J. O. Kephart; D. M. Chess (2003). "The vision of autonomic computing".
3171:. p. 69: "There is a tradition in control theory that one deals with a
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Analysis of the dynamic psychological systems: methods and applications
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The Fifth Discipline: The Art and Practice of the Learning Organization
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refers to a closed chain of cause and effect that creates the feedback.
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used in steam engines. He distinguished those that lead to a continued
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occurs when outputs of a system are routed back as inputs as part of a
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2723:"Second Law of Thermodynamics with Discrete Quantum Feedback Control"
1452:. Negative feedback is often deliberately introduced to increase the
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Business Dynamics: Systems Thinking and Modeling for a Complex World
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Authority, liberty, & automatic machinery in early modern Europe
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The simplest form of a feedback amplifier can be represented by the
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it is out of phase with the input , it is called negative feedback.
3139:
Sixth Assessment Report (AR6), Working Group I, IPCC, 2021, p. 96.
936:
Some systems with feedback can have very complex behaviors such as
615:
By the end of 1912, researchers using early electronic amplifiers (
540:, for maintaining water at a constant level, invented in 270 BC in
3681:
2804:
2739:
2563:, American Scientist, Vol. 45, No. 4 (SEPTEMBER 1957), pp. 343-371
2061:
to portray the information feedback at work in a system. The word
1852:
1721:
1610:
1398:
1294:
to keep the face of the windmill pointing into the wind. In 1787,
1171:
700:
As an example of negative feedback, the diagram might represent a
685:
677:
482:
874:
This confusion may arise because feedback can be used to provide
1080:
582:
3685:
3322:
For an analysis of desensitization in the system pictured, see
2345:
Ramaprasad, Arkalgud (1983). "On the definition of feedback".
2109:
Feedback Systems: An Introduction for Scientists and Engineers
1884:
518:
Feedback Systems: An Introduction for Scientists and Engineers
1192:
loop whereby melting snow exposes more dark ground (of lower
502:
that forms a circuit or loop. The system can then be said to
1935: – Howling caused by a circular path in an audio system
1750:. Latches and flip-flops are fundamental building blocks of
1746:
have one or two outputs. It is the basic storage element in
1498:
Electronic feedback loops are used to control the output of
1196:), which in turn absorbs heat and causes more snow to melt.
961:
Feedback can give rise to incredibly complex behaviors. The
604:
used the term "feed-back" as a noun to refer to (undesired)
2268:, Nobel Lecture, 11 December 1909. Retrieved 19 March 2012.
1774:
Flip-flops can be either simple (transparent or opaque) or
574:
of their production. Early steam engines employed a purely
2035:"Chapter 9: Information feedback and causal loop diagrams"
1271:
was used to regulate the flow of water in Greek and Roman
3175:
in which a negative sign is included in the feedback loop
2986:"Allosteric controls of amphilbolic pathways in bacteria"
1929: – Practice in the field of learning and achievement
1836:
Feedback is also a useful design principle for designing
3270:
Basic Electronics: Devices, Circuits and IT Fundamentals
1991: – Process of repeating items in a self-similar way
554:
were used to regulate the distance and pressure between
3657:
New Issues and Paradigms in Research on Social Dilemmas
3243:. Boca Raton, FL, USA: CRC Press. pp. 13.1–13.14.
1900:
1685:, to distinguish it from an audio frequency oscillator.
3449:
Garg, Rakesh Kumar; Ashish Dixit; Pavan Yadav (2008).
2684:"Feedback for physicists: A tutorial essay on control"
1298:
regulated the rotation speed of a windmill by using a
1275:; similar float valves are used to regulate fuel in a
536:
The first ever known artificial feedback device was a
2721:
Sagawa, Takahiro; Ueda, Masahito (26 February 2008).
2381:. Baltimore, MD, US: Johns Hopkins University Press.
1997: – Tendency to oscillate at certain frequencies
1662:, and the sounds produced by electronic beepers and
4090:
4037:
3979:
3916:
3883:
3815:
3740:
3719:
3326:"§5.3.1 Effect of feedback on parameter variations"
3210:
Journal of the American Society for Naval Engineers
1415:The use of feedback is widespread in the design of
1383:but mechanical feedback was replaced by electronic
1243:errors, and the derivative term is a prediction of
1176:
Some effects of global warming can either enhance (
3578:
2065:refers to cause-and-effect relationships. The word
1279:and also used to regulate tank water level in the
3285:If the feedback signal reduces the input signal,
2266:"Electrical oscillations and wireless telegraphy"
1699:(RF) range of about 100 kHz to 100 GHz.
894:component. As Connellan and Zemke (1993) put it:
682:An example of a negative feedback loop with goals
3417:
3415:
3413:
3411:
1688:An audio oscillator produces frequencies in the
1239:error, the integral term on the accumulation of
2788:"Thermodynamics of feedback controlled systems"
2410:H.S. Black, "Stabilized feed-back amplifiers",
917:
905:feedback tells us how good, bad or indifferent.
896:
734:
726:
639:
508:
3241:Circuit Analysis and Feedback Amplifier Theory
1580:circuits for volatile storage of information.
3697:
3332:. Pearson Education India. pp. 134–135.
2340:
2338:
2336:
2193:Maxwell, James Clerk (1868). "On Governors".
2103:Karl Johan Åström; Richard M. Murray (2008).
1255:For feedback in the educational context, see
1231:using a control-loop feedback mechanism is a
910:Limitations of negative and positive feedback
464:
8:
3379:
3377:
3112:"The Study of Earth as an Integrated System"
2230:HH Cole, "Improvement in Fluting-Machines",
2170:Designing Kinetics for Architectural Facades
1985: – Incentive that has a contrary result
1658:, clock signals that regulate computers and
1510:if no output feedback is being employed and
1487:. Design to ensure stability often involves
1387:once small, robust and powerful single-chip
3428:. New Age International. pp. 224–225.
3425:Electronics (fundamentals And Applications)
2284:A history of control engineering, 1800–1930
1669:Oscillators are often characterized by the
3704:
3690:
3682:
3633:. Chapter 18: Games as Cybernetic Systems.
2436:Proceedings of the Royal Society of London
2422:
2420:
2414:, vol. 53, pp. 114–120, January 1934.
2370:
2368:
2276:
2274:
2195:Proceedings of the Royal Society of London
1583:The loud squeals that sometimes occurs in
1527:astable circuits, which act as oscillators
1321:. Steam engines also use float valves and
471:
457:
27:
3009:
2925:
2876:
2803:
2738:
2447:
2111:. Princeton University Press. p. 1.
1959: – Most basic type of physical force
1695:An RF oscillator produces signals in the
901:feedback tells us how much and how many.
745:Even before these terms were being used,
3479:Digital electronics and design with VHDL
2308:
2306:
2014: – Unforeseen outcomes of an action
1448:; otherwise, the feedback is said to be
1247:error, based on current rate of change.
956:
669:
516:Karl Johan Åström and Richard M.Murray,
3536:J. L. Hellerstein; Y. Diao; S. Parekh;
2786:Cao, F. J.; Feito, M. (10 April 2009).
2548:Circuit Theory of Linear Noisy Networks
2533:Charles S. Carver, Michael F. Scheier:
2025:
1692:range, about 16 Hz to 20 kHz.
37:
30:
3512:(EE 42/100 Lecture 24 from Berkeley)
3273:. PHI Learning Pvt. Ltd. p. 191.
2616:Introduction to Bioregulatory Medicine
2467:from the original on 26 December 2010.
1550:reduction or to establish a specified
1060:do not imply that the feedback causes
3542:Feedback Control of Computing Systems
3237:"Chapter 13: General feedback theory"
3122:from the original on 2 November 2016.
2561:The Experimental Analysis of Behavior
2546:Hermann A Haus and Richard B. Adler,
1763:, and such a circuit is described as
1313:in 1788 to regulate the speed of his
7:
3357:"Negative Feedback & Distortion"
2857:Cytokine & Growth Factor Reviews
2493:. New York: Doubleday. p. 424.
2329:from the original on 23 August 2000.
2163:
2161:
1325:as mechanical regulation devices. A
3085:Scheff, Thomas (2 September 2009).
2918:10.20892/j.issn.2095-3941.2017.0029
2682:Bechhoefer, John (31 August 2005).
1807:. From a software perspective, the
1145:hypothalamic–pituitary–adrenal axis
3860:Evolutionary developmental biology
3222:10.1111/j.1559-3584.1922.tb04958.x
3143:from the original on 21 July 2022.
2610:Alta Smit; Arturo O'Byrne (2011).
2535:On the Self-Regulation of Behavior
2144:. Johns Hopkins University Press.
1863:input and a video output, e.g., a
718:the "feed-back" action is positive
218:Evolutionary developmental biology
14:
3585:. New York: Basic Books. p.
2537:Cambridge University Press, 2001
953:Mathematics and dynamical systems
593:and the mathematics of feedback.
562:since the 17th century. In 1788,
3669:
3482:. Morgan Kaufmann. p. 329.
3087:"The Emotional/Relational World"
1888:
1859:. It involves a loop between a
1233:proportional-integral-derivative
1227:The most common general-purpose
690:A positive feedback loop example
3994:Ordinary differential equations
3455:. Firewall Media. p. 280.
2900:Vlahopoulos, SA (August 2017).
1646:(DC) from a power supply to an
1491:to control the location of the
1329:of Watt's governor was done by
385:Ordinary differential equations
4052:Partial differential equations
2757:10.1103/PhysRevLett.100.080403
2316:An introduction to cybernetics
1317:was one factor leading to the
656:Positive and negative feedback
256:Partial differential equations
1:
3392:. McGraw-Hill. Archived from
3153:
3047:10.1016/S0022-2836(61)80072-7
2906:Cancer Biology & Medicine
2869:10.1016/j.cytogfr.2015.06.001
2427:Maxwell, James Clerk (1868).
1523:are widely used and include:
3659:, New York: Springer, 2008.
3639:, Malkov A., Khaltourina D.
3577:Hofstadter, Douglas (2007).
3161:Dynamics of Feedback Systems
3002:10.1128/MMBR.34.1.20-39.1970
2041:. Island Press. pp. 99
1617:op-amp relaxation oscillator
1485:gain margin and phase margin
1190:ice–albedo positive feedback
3802:Particle swarm optimization
3309:P. Horowitz & W. Hill,
2517:, McGraw Hill/Irwin, 2000.
1634:electronic signal, often a
1514:if feedback is being used.
1473:Nyquist stability criterion
1106:, which were identified by
1102:are used to create genetic
105:Particle swarm optimization
4207:
4047:Reaction-diffusion systems
3772:Self-organized criticality
3476:Volnei A. Pedroni (2008).
3422:Chattopadhyay, D. (2006).
3384:Snelgrove, Martin (2011).
3361:learnabout-electronics.org
2963:10.1016/j.cyto.2016.01.021
2822:10.1103/PhysRevE.79.041118
1963:Human–computer interaction
1878:
1829:
1818:
1630:that produces a periodic,
1220:
1203:
1165:
1018:
1012:
968:
659:
252:Reaction–diffusion systems
81:Self-organized criticality
18:
3830:Artificial neural network
3324:S.K Bhattacharya (2011).
2984:Sanwal, BD (March 1970).
2708:10.1103/RevModPhys.77.783
2688:Reviews of Modern Physics
2375:David A. Mindell (2002).
2105:"§1.1: What is feedback?"
1875:Human resource management
1385:engine management systems
608:between components of an
193:Artificial neural network
21:Feedback (disambiguation)
3908:Evolutionary game theory
3835:Evolutionary computation
3767:Collective consciousness
3544:. John Wiley & Sons.
2039:Modeling the Environment
1679:low-frequency oscillator
1673:of their output signal:
1085:gene regulatory networks
647:translated into action.
444:Evolutionary game theory
334:Second-order cybernetics
198:Evolutionary computation
114:Collective consciousness
3926:Social network analysis
3865:Artificial intelligence
3797:Ant colony optimization
3757:Collective intelligence
2727:Physical Review Letters
2487:Peter M. Senge (1990).
2281:Stuart Bennett (1979).
2250:accessed 23 March 2012.
2248:US Patent 47,769 (1865)
2234:accessed 23 March 2012.
2232:US Patent 55,469 (1866)
2168:Moloney, Jules (2011).
2057:This chapter describes
2012:Unintended consequences
1957:Fundamental interaction
1656:television transmitters
1323:pressure release valves
1168:Climate change feedback
925:Other types of feedback
882:, and often has both a
222:Artificial intelligence
136:Social network analysis
101:Ant colony optimization
73:Collective intelligence
4186:Management cybernetics
4057:Dissipative structures
3898:Rational choice theory
3508:5 October 2016 at the
3503:Latches and Flip Flops
3330:Linear Control Systems
3311:The Art of Electronics
3173:negative feedback loop
3163:, New York: J. Wiley.
2449:10.1098/rspl.1867.0055
2412:Electrical Engineering
2322:. Chapman & Hall.
2313:W. Ross Ashby (1957).
2264:Karl Ferdinand Braun,
2207:10.1098/rspl.1867.0055
1897:This section is empty.
1734:
1718:Latches and flip-flops
1642:. Oscillators convert
1619:
1489:frequency compensation
1412:
1395:Electronic engineering
1267:In ancient times, the
1263:Mechanical engineering
1212:state space (controls)
1185:
1015:Biological interaction
966:
922:
907:
743:
730:
691:
683:
675:
644:
522:
488:
435:Rational choice theory
260:Dissipative structures
3870:Evolutionary robotics
3787:Agent-based modelling
3267:Santiram Kal (2009).
3235:Wai-Kai Chen (2005).
2618:. Thieme. p. 6.
2359:10.1002/bs.3830280103
2123:Online version found
1881:performance appraisal
1832:User interface design
1826:User interface design
1725:
1712:relaxation oscillator
1624:electronic oscillator
1614:
1556:asymptotic gain model
1402:
1381:vacuum timing advance
1327:mathematical analysis
1319:Industrial Revolution
1221:Further information:
1175:
1138:Allosteric regulation
960:
838:discrepancy-enhancing
761:of the same quality.
751:centrifugal governors
689:
681:
673:
552:Centrifugal governors
486:
363:Theory of computation
226:Evolutionary robotics
93:Agent-based modelling
4029:Coupled map lattices
3989:Time series analysis
3931:Small-world networks
3678:at Wikimedia Commons
3645:Moscow: URSS, 2006.
2059:causal loop diagrams
2033:Andrew Ford (2010).
1815:Software Development
1769:finite-state machine
1358:Elmer Ambrose Sperry
1307:centrifugal governor
1300:centrifugal pendulum
1127:predator-prey cycles
1047:insulin oscillations
842:discrepancy-reducing
722:Harold Stephen Black
714:regenerative circuit
602:Karl Ferdinand Braun
576:reciprocating motion
414:Coupled map lattices
380:Time series analysis
140:Small-world networks
19:For other uses, see
4191:Electronic feedback
4009:Population dynamics
3903:Bounded rationality
3845:Genetic programming
3581:I Am a Strange loop
2814:2009PhRvE..79d1118C
2749:2008PhRvL.100h0403S
2700:2005RvMP...77..783B
2653:2009JPCA..113...19W
2001:Stability criterion
1927:Corrective feedback
1752:digital electronics
1648:alternating current
1419:components such as
1409:unilateral elements
1405:ideal block diagram
1391:became affordable.
1364:designed the first
1344:John McFarlane Gray
1331:James Clerk Maxwell
1286:The Dutch inventor
1257:corrective feedback
1216:full state feedback
747:James Clerk Maxwell
626:The development of
587:James Clerk Maxwell
439:Bounded rationality
397:Population dynamics
306:Conversation theory
206:Genetic programming
131:Scale-free networks
63:Collective behavior
4155:Computation theory
4150:Information theory
4105:Operationalization
3981:Nonlinear dynamics
3893:Prisoner's dilemma
3840:Genetic algorithms
2612:"Bipolar feedback"
2347:Behavioral Science
1983:Perverse incentive
1735:
1628:electronic circuit
1620:
1495:of the amplifier.
1413:
1362:Sperry Corporation
1186:
1182:negative feedbacks
1178:positive feedbacks
967:
773:the change of the
692:
684:
676:
610:electronic circuit
489:
430:Prisoner's dilemma
375:Nonlinear dynamics
330:Operationalization
326:Information theory
202:Genetic algorithms
4163:
4162:
4067:Cellular automata
4039:Pattern formation
3971:Adaptive networks
3762:Collective action
3732:Self-organization
3674:Media related to
3596:978-0-465-03079-8
3489:978-0-12-374270-4
3452:Basic Electronics
3435:978-81-224-1780-7
3135:Technical Summary
2792:Physical Review E
2661:10.1021/jp804420g
2550:, MIT Press, 1959
2523:978-0-07-238915-9
2513:John D. Sterman,
2500:978-0-385-26094-7
2294:978-0-906048-07-8
2151:978-0-8018-3939-9
1917:
1916:
1865:television screen
1857:acoustic feedback
1767:. When used in a
1732:D-type flip flops
1562:Positive feedback
1538:Negative feedback
1502:devices, such as
1483:to determine the
1445:negative feedback
1431:elements such as
1288:Cornelius Drebbel
938:chaotic behaviors
666:Positive feedback
662:Negative feedback
570:, for use in the
481:
480:
268:Cellular automata
242:Pattern formation
173:Adaptive networks
77:Collective action
46:Self-organization
4198:
4077:Self-replication
3966:Dynamic networks
3855:Machine learning
3782:Phase transition
3706:
3699:
3692:
3683:
3673:
3613:Katie Salen and
3601:
3600:
3584:
3574:
3568:
3567:
3563:
3557:
3556:
3552:
3546:
3545:
3533:
3527:
3526:
3522:
3516:
3500:
3494:
3493:
3473:
3467:
3466:
3446:
3440:
3439:
3419:
3406:
3405:
3403:
3401:
3381:
3372:
3371:
3369:
3367:
3353:
3347:
3346:
3320:
3314:
3307:
3301:
3298:
3292:
3291:
3264:
3258:
3257:
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3225:
3205:
3199:
3198:
3197:
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3180:
3178:
3158:
3155:
3150:
3144:
3130:
3124:
3123:
3108:
3102:
3101:
3099:
3097:
3091:Psychology Today
3082:
3076:
3073:
3067:
3066:
3030:
3024:
3023:
3013:
2981:
2975:
2974:
2946:
2940:
2939:
2929:
2897:
2891:
2890:
2880:
2848:
2842:
2841:
2807:
2783:
2777:
2776:
2742:
2718:
2712:
2711:
2679:
2673:
2672:
2641:J. Phys. Chem. A
2636:
2630:
2629:
2607:
2601:
2591:
2585:
2570:
2564:
2557:
2551:
2544:
2538:
2531:
2525:
2511:
2505:
2504:
2484:
2478:
2475:
2469:
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2451:
2433:
2424:
2415:
2408:
2402:
2399:
2393:
2392:
2372:
2363:
2362:
2342:
2331:
2330:
2328:
2321:
2310:
2301:
2298:
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2269:
2257:
2251:
2241:
2235:
2225:
2219:
2218:
2190:
2184:
2183:
2165:
2156:
2155:
2134:
2128:
2122:
2100:
2094:
2093:
2091:
2089:
2084:. MerriamWebster
2078:
2072:
2071:
2030:
1977:Optical feedback
1969:Low-key feedback
1912:
1909:
1899:You can help by
1892:
1885:
1765:sequential logic
1748:sequential logic
1389:microcontrollers
1370:Nicolas Minorsky
1350:coined the word
1033:systems such as
971:Dynamical system
822:self-reinforcing
739:
596:The verb phrase
520:
500:cause-and-effect
473:
466:
459:
350:Systems thinking
276:Self-replication
214:Machine learning
168:Dynamic networks
89:Phase transition
28:
4206:
4205:
4201:
4200:
4199:
4197:
4196:
4195:
4166:
4165:
4164:
4159:
4125:System dynamics
4086:
4072:Spatial ecology
4033:
3975:
3961:Systems biology
3912:
3879:
3850:Artificial life
3820:
3811:
3807:Swarm behaviour
3792:Synchronization
3752:Social dynamics
3743:
3736:
3715:
3713:Complex systems
3710:
3666:
3610:
3608:Further reading
3605:
3604:
3597:
3576:
3575:
3571:
3565:
3564:
3560:
3554:
3553:
3549:
3535:
3534:
3530:
3524:
3523:
3519:
3510:Wayback Machine
3501:
3497:
3490:
3475:
3474:
3470:
3463:
3448:
3447:
3443:
3436:
3421:
3420:
3409:
3399:
3397:
3396:on 19 July 2013
3383:
3382:
3375:
3365:
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3355:
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3321:
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3308:
3304:
3299:
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3281:
3266:
3265:
3261:
3251:
3234:
3233:
3229:
3207:
3206:
3202:
3195:
3188:
3187:
3183:
3176:
3156:
3151:
3147:
3131:
3127:
3110:
3109:
3105:
3095:
3093:
3084:
3083:
3079:
3074:
3070:
3032:
3031:
3027:
2983:
2982:
2978:
2948:
2947:
2943:
2899:
2898:
2894:
2850:
2849:
2845:
2785:
2784:
2780:
2720:
2719:
2715:
2681:
2680:
2676:
2638:
2637:
2633:
2626:
2609:
2608:
2604:
2592:
2588:
2584:(1992) page 123
2571:
2567:
2558:
2554:
2545:
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2532:
2528:
2512:
2508:
2501:
2486:
2485:
2481:
2476:
2472:
2464:
2431:
2426:
2425:
2418:
2409:
2405:
2400:
2396:
2389:
2374:
2373:
2366:
2344:
2343:
2334:
2326:
2319:
2312:
2311:
2304:
2295:
2280:
2279:
2272:
2258:
2254:
2242:
2238:
2226:
2222:
2192:
2191:
2187:
2180:
2167:
2166:
2159:
2152:
2136:
2135:
2131:
2119:
2102:
2101:
2097:
2087:
2085:
2080:
2079:
2075:
2053:
2032:
2031:
2027:
2022:
2017:
1922:
1913:
1907:
1904:
1883:
1877:
1846:
1838:user interfaces
1834:
1828:
1823:
1821:Software review
1817:
1796:
1720:
1697:radio frequency
1609:
1564:
1540:
1427:, and stateful
1397:
1305:The use of the
1265:
1253:
1225:
1208:
1202:
1170:
1164:
1162:Climate science
1027:
1017:
1011:
1003:Maxwell's demon
998:
985:
969:Main articles:
955:
950:
927:
912:
826:self-correcting
767:
737:
668:
660:Main articles:
658:
653:
568:Matthew Boulton
531:economic theory
527:
521:
515:
477:
448:
447:
446:
441:
437:
432:
427:
417:
416:
411:
407:
403:
399:
395:
391:
387:
382:
377:
367:
366:
365:
360:
356:
352:
348:
346:Systems science
344:
342:System dynamics
340:
336:
332:
328:
324:
320:
316:
312:
308:
303:
298:
284:
283:
278:
274:
272:Spatial ecology
270:
266:
262:
258:
254:
249:
244:
234:
233:
228:
224:
220:
216:
212:
210:Artificial life
208:
204:
200:
195:
190:
176:
175:
170:
166:
164:Systems biology
162:
158:
154:
150:
146:
142:
138:
133:
128:
118:
117:
116:
111:
109:Swarm behaviour
107:
103:
99:
97:Synchronization
95:
91:
87:
83:
79:
75:
70:
68:Social dynamics
65:
55:
54:
53:
48:
32:Complex systems
24:
17:
12:
11:
5:
4204:
4202:
4194:
4193:
4188:
4183:
4181:Control theory
4178:
4168:
4167:
4161:
4160:
4158:
4157:
4152:
4147:
4142:
4137:
4132:
4127:
4122:
4117:
4115:Self-reference
4112:
4107:
4102:
4096:
4094:
4092:Systems theory
4088:
4087:
4085:
4084:
4079:
4074:
4069:
4064:
4059:
4054:
4049:
4043:
4041:
4035:
4034:
4032:
4031:
4026:
4021:
4019:Multistability
4016:
4011:
4006:
4001:
3996:
3991:
3985:
3983:
3977:
3976:
3974:
3973:
3968:
3963:
3958:
3953:
3948:
3943:
3938:
3933:
3928:
3922:
3920:
3914:
3913:
3911:
3910:
3905:
3900:
3895:
3889:
3887:
3881:
3880:
3878:
3877:
3872:
3867:
3862:
3857:
3852:
3847:
3842:
3837:
3832:
3826:
3824:
3813:
3812:
3810:
3809:
3804:
3799:
3794:
3789:
3784:
3779:
3777:Herd mentality
3774:
3769:
3764:
3759:
3754:
3748:
3746:
3738:
3737:
3735:
3734:
3729:
3723:
3721:
3717:
3716:
3711:
3709:
3708:
3701:
3694:
3686:
3680:
3679:
3665:
3664:External links
3662:
3661:
3660:
3653:
3634:
3615:Eric Zimmerman
3609:
3606:
3603:
3602:
3595:
3569:
3558:
3547:
3528:
3517:
3495:
3488:
3468:
3462:978-8131803028
3461:
3441:
3434:
3407:
3373:
3348:
3338:
3315:
3302:
3293:
3279:
3259:
3249:
3227:
3216:(2): 280–309.
3200:
3181:
3145:
3125:
3118:. NASA. 2016.
3103:
3077:
3068:
3041:(3): 318–356.
3025:
2990:Bacteriol. Rev
2976:
2941:
2912:(3): 254–270.
2892:
2863:(4): 389–403.
2843:
2778:
2713:
2694:(3): 783–836.
2674:
2631:
2624:
2602:
2586:
2582:978-0306437465
2565:
2552:
2539:
2526:
2506:
2499:
2479:
2470:
2429:"On Governors"
2416:
2403:
2394:
2387:
2364:
2332:
2302:
2293:
2270:
2252:
2236:
2220:
2185:
2179:978-0415610346
2178:
2157:
2150:
2129:
2117:
2095:
2073:
2051:
2024:
2023:
2021:
2018:
2016:
2015:
2009:
2003:
1998:
1992:
1986:
1980:
1974:
1973:
1972:
1960:
1954:
1948:
1942:
1936:
1933:Audio feedback
1930:
1923:
1921:
1918:
1915:
1914:
1908:September 2020
1895:
1893:
1879:Main article:
1876:
1873:
1855:equivalent of
1849:Video feedback
1845:
1844:Video feedback
1842:
1830:Main article:
1827:
1824:
1819:Main article:
1816:
1813:
1795:
1792:
1719:
1716:
1701:
1700:
1693:
1686:
1644:direct current
1608:
1605:
1597:audio feedback
1563:
1560:
1539:
1536:
1535:
1534:
1531:
1528:
1520:multivibrators
1396:
1393:
1374:PID controller
1264:
1261:
1252:
1249:
1223:PID controller
1206:Control theory
1204:Main article:
1201:
1200:Control theory
1198:
1180:) or inhibit (
1166:Main article:
1163:
1160:
1122:consumption).
1116:feedback loops
1108:François Jacob
1070:mirror neurons
1013:Main article:
1010:
1007:
997:
994:
983:Control theory
963:Mandelbrot set
954:
951:
949:
946:
926:
923:
911:
908:
810:
809:
804:(positive) or
786:
781:(positive) or
766:
763:
702:cruise control
657:
654:
652:
649:
591:control theory
526:
523:
513:
479:
478:
476:
475:
468:
461:
453:
450:
449:
428:
423:
422:
419:
418:
405:Multistability
378:
373:
372:
369:
368:
338:Self-reference
299:
292:Systems theory
290:
289:
286:
285:
245:
240:
239:
236:
235:
191:
182:
181:
178:
177:
129:
124:
123:
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119:
85:Herd mentality
66:
61:
60:
57:
56:
49:
44:
43:
40:
39:
35:
34:
15:
13:
10:
9:
6:
4:
3:
2:
4203:
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4179:
4177:
4174:
4173:
4171:
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4153:
4151:
4148:
4146:
4143:
4141:
4138:
4136:
4133:
4131:
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4126:
4123:
4121:
4120:Goal-oriented
4118:
4116:
4113:
4111:
4108:
4106:
4103:
4101:
4098:
4097:
4095:
4093:
4089:
4083:
4082:Geomorphology
4080:
4078:
4075:
4073:
4070:
4068:
4065:
4063:
4060:
4058:
4055:
4053:
4050:
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4030:
4027:
4025:
4022:
4020:
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4015:
4012:
4010:
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4005:
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4000:
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3992:
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3984:
3982:
3978:
3972:
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3648:
3644:
3643:
3638:
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3632:
3631:0-262-24045-9
3628:
3624:
3620:
3619:Rules of Play
3616:
3612:
3611:
3607:
3598:
3592:
3588:
3583:
3582:
3573:
3570:
3562:
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3538:D. M. Tilbury
3532:
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2172:. Routledge.
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2164:
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2052:9781610914253
2048:
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2036:
2029:
2026:
2019:
2013:
2010:
2007:
2004:
2002:
1999:
1996:
1993:
1990:
1987:
1984:
1981:
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1755:
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1737:A latch or a
1733:
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1724:
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1691:
1687:
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1675:
1674:
1672:
1667:
1665:
1661:
1660:quartz clocks
1657:
1653:
1649:
1645:
1641:
1637:
1633:
1629:
1625:
1618:
1613:
1606:
1604:
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1598:
1595:are known as
1594:
1590:
1586:
1585:audio systems
1581:
1579:
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1537:
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1521:
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1509:
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1496:
1494:
1490:
1486:
1482:
1479:developed by
1478:
1474:
1470:
1466:
1465:Harry Nyquist
1462:
1460:
1455:
1451:
1447:
1446:
1440:
1438:
1434:
1430:
1429:logic circuit
1426:
1422:
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1390:
1386:
1382:
1377:
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1349:
1348:Joseph Farcot
1345:
1341:
1340:
1339:Great Eastern
1334:
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1117:
1113:
1112:Jacques Monod
1109:
1105:
1101:
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1094:
1093:Lac repressor
1090:
1086:
1082:
1077:
1073:
1071:
1067:
1063:
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1055:
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991:
990:edge of chaos
984:
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979:Edge of chaos
976:
972:
964:
959:
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947:
945:
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939:
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931:
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921:
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909:
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904:
900:
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893:
892:
887:
886:
881:
877:
872:
870:
869:
864:
863:
862:reinforcement
859:
855:
851:
847:
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839:
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631:
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624:
622:
618:
613:
611:
607:
603:
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594:
592:
588:
584:
579:
577:
573:
572:steam engines
569:
565:
561:
557:
553:
549:
547:
543:
539:
534:
532:
524:
519:
512:
507:
505:
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474:
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452:
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420:
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376:
371:
370:
364:
361:
359:
355:
351:
347:
343:
339:
335:
331:
327:
323:
319:
318:Goal-oriented
315:
311:
307:
302:
297:
293:
288:
287:
282:
281:Geomorphology
279:
277:
273:
269:
265:
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248:
243:
238:
237:
232:
229:
227:
223:
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215:
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194:
189:
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174:
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64:
59:
58:
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29:
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3946:Graph theory
3875:Evolvability
3656:
3641:
3637:Korotayev A.
3618:
3580:
3572:
3561:
3550:
3541:
3531:
3520:
3513:
3498:
3478:
3471:
3451:
3444:
3424:
3398:. Retrieved
3394:the original
3389:
3386:"Oscillator"
3364:. Retrieved
3360:
3351:
3343:
3329:
3318:
3310:
3305:
3296:
3286:
3284:
3269:
3262:
3254:
3240:
3230:
3213:
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3148:
3133:
3132:Fig. TS.17,
3128:
3115:
3106:
3094:. Retrieved
3090:
3080:
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3038:
3034:
3028:
2996:(1): 20–39.
2993:
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2647:(1): 19–22.
2644:
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2559:BF Skinner,
2555:
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2098:
2086:. Retrieved
2076:
2066:
2062:
2056:
2042:
2038:
2028:
2006:Strange loop
1951:Feed forward
1905:
1901:adding to it
1896:
1861:video camera
1847:
1835:
1797:
1788:
1783:
1779:
1773:
1758:
1756:
1736:
1728:ring counter
1709:
1702:
1683:synthesizers
1668:
1621:
1582:
1565:
1544:out of phase
1543:
1541:
1518:
1516:
1511:
1507:
1497:
1481:Hendrik Bode
1471:derived the
1463:
1449:
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1441:
1414:
1404:
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1337:
1335:
1315:steam engine
1304:
1285:
1281:flush toilet
1273:water clocks
1266:
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975:Chaos theory
948:Applications
942:
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913:
902:
899:Quantitative
898:
897:
891:quantitative
889:
883:
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866:
860:
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853:
850:degenerative
849:
846:regenerative
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621:regeneration
614:
598:to feed back
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509:
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491:
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231:Evolvability
196:
152:Graph theory
134:
71:
25:
4145:Autopoiesis
4140:Cybernetics
4130:Sensemaking
4100:Homeostasis
4062:Percolation
4024:Bifurcation
3999:Phase space
3885:Game theory
3742:Collective
3192:PID Control
3189:Araki, M.,
3157: 1981
2957:: 127–135.
2442:: 270–283.
2201:: 270–283.
1945:Cybernetics
1664:video games
1640:square wave
1632:oscillating
1512:closed loop
1425:oscillators
1407:made up of
1277:carburettor
1269:float valve
1114:in 1961 as
1021:Homeostasis
903:Qualitative
885:qualitative
876:information
830:reinforcing
808:(negative).
785:(negative).
765:Terminology
707:speedometer
628:cybernetics
538:float valve
425:Game theory
409:Bifurcation
389:Phase space
354:Sensemaking
322:Homeostasis
301:Autopoiesis
296:cybernetics
264:Percolation
4170:Categories
3956:Robustness
3936:Centrality
3822:adaptation
3720:Background
3035:J Mol Biol
2082:"feedback"
2020:References
1805:IBM Tivoli
1615:A popular
1607:Oscillator
1593:rock music
1589:PA systems
1573:hysteresis
1569:oscillates
1548:distortion
1504:amplifiers
1500:electronic
1477:Bode plots
1433:flip-flops
1421:amplifiers
1417:electronic
1311:James Watt
1229:controller
1184:) warming.
1152:psychology
1039:ecosystems
1031:biological
1025:Allostasis
1019:See also:
868:punishment
564:James Watt
556:millstones
542:Alexandria
393:Attractors
188:adaptation
160:Robustness
144:Centrality
4004:Attractor
3817:Evolution
3727:Emergence
3623:MIT Press
2830:1539-3755
2805:0805.4824
2765:0031-9007
2740:0710.0956
2138:Otto Mayr
2088:1 January
1995:Resonance
1989:Recursion
1939:Black box
1809:autonomic
1780:flip-flop
1739:flip-flop
1705:inverters
1671:frequency
1636:sine wave
1601:loop gain
1508:open loop
1469:Bell Labs
1459:oscillate
1454:stability
1368:in 1912.
1366:autopilot
1333:in 1868.
1251:Education
1120:metabolic
1097:activator
1089:Repressor
1043:biosphere
1041:, or the
1035:organisms
834:balancing
783:narrowing
560:windmills
504:feed back
184:Evolution
51:Emergence
4176:Feedback
4110:Feedback
3918:Networks
3744:behavior
3676:Feedback
3625:. 2004.
3540:(2004).
3506:Archived
3141:Archived
3120:Archived
3116:nasa.gov
3063:19804795
3055:13718526
2971:26854213
2951:Cytokine
2936:28884042
2887:26119834
2838:19518184
2773:18352605
2669:19072712
2462:Archived
2458:51751195
2353:: 4–13.
2324:Archived
2140:(1989).
1920:See also
1794:Software
1726:A 4-bit
1578:bistable
1450:positive
1437:counters
1296:Tom Mead
1156:hormones
1134:zymology
1100:proteins
1058:negative
1054:positive
880:motivate
858:negative
854:positive
818:negative
814:positive
779:widening
759:decrease
755:increase
606:coupling
514:—
492:Feedback
314:Feedback
247:Fractals
126:Networks
4135:Entropy
3951:Scaling
3400:1 March
3096:10 July
3020:4315011
2927:5570602
2878:4526340
2810:Bibcode
2745:Bibcode
2696:Bibcode
2649:Bibcode
1869:monitor
1851:is the
1801:IBM Db2
1784:latches
1776:clocked
1743:circuit
1360:of the
1292:fantail
1237:present
1104:operons
1009:Biology
996:Physics
806:unhappy
792:of the
790:valence
617:audions
525:History
358:Variety
310:Entropy
156:Scaling
3941:Motifs
3649:
3629:
3593:
3486:
3459:
3432:
3366:7 June
3336:
3277:
3247:
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3018:
3011:378347
3008:
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2215:112510
2213:
2176:
2148:
2115:
2063:causal
2049:
1730:using
1626:is an
1591:, and
1245:future
1194:albedo
1095:) and
981:, and
888:and a
798:effect
794:action
738:
148:Motifs
38:Topics
4014:Chaos
3196:(PDF)
3059:S2CID
2800:arXiv
2735:arXiv
2465:(PDF)
2454:S2CID
2432:(PDF)
2327:(PDF)
2320:(PDF)
2211:JSTOR
1853:video
1760:state
1741:is a
1690:audio
1652:radio
1638:or a
1493:poles
1353:servo
1091:(see
1081:genes
820:with
802:happy
651:Types
635:Ashby
546:Egypt
496:chain
401:Chaos
3819:and
3647:ISBN
3627:ISBN
3591:ISBN
3484:ISBN
3457:ISBN
3430:ISBN
3402:2012
3368:2024
3334:ISBN
3287:i.e.
3275:ISBN
3245:ISBN
3179:..."
3165:ISBN
3098:2013
3051:PMID
3016:PMID
2967:PMID
2932:PMID
2883:PMID
2834:PMID
2826:ISSN
2769:PMID
2761:ISSN
2665:PMID
2620:ISBN
2595:ISBN
2578:ISBN
2519:ISBN
2495:ISBN
2383:ISBN
2289:ISBN
2174:ISBN
2146:ISBN
2125:here
2113:ISBN
2090:2022
2067:loop
2047:ISBN
1803:and
1654:and
1552:gain
1435:and
1336:The
1241:past
1143:The
1110:and
1083:and
1062:good
1056:and
1023:and
856:and
848:and
840:and
832:and
824:and
816:and
788:the
664:and
583:1868
294:and
186:and
3218:doi
3043:doi
3006:PMC
2998:doi
2959:doi
2922:PMC
2914:doi
2873:PMC
2865:doi
2818:doi
2753:doi
2731:100
2704:doi
2657:doi
2645:113
2444:doi
2355:doi
2203:doi
1903:.
1867:or
1622:An
1467:at
1309:by
1150:In
1140:).
1132:In
1066:bad
1064:or
1029:In
878:or
865:or
844:or
796:or
775:gap
736:...
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558:in
498:of
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