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1056:, 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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720:. 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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1169:. 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.
2583:"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
648:(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.
559:. 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.
1557:, 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.
1782:, 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
1822:(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
589:, 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.
1610:. 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
1129:. 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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976:(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
634:), 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.
1789:(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
1301:(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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2255:"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
1147:, 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
611:, 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.
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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
2239:"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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1517:. 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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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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1229:, and so forth. In the context of control theory, "feedback" is traditionally assumed to specify "negative feedback".
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1976: – 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
735:'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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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).
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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
2864:"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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1882:. 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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2271:"...as far as possible the circuit has no feed-back into the system being investigated."
1982:– 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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1964: – 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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3324:, 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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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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1958: – 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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3525:"...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".
3182:. 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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2734:"Second Law of Thermodynamics with Discrete Quantum Feedback Control"
1463:. 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.
3150:
Sixth Assessment Report (AR6), Working Group I, IPCC, 2021, p. 96.
947:
Some systems with feedback can have very complex behaviors such as
626:
By the end of 1912, researchers using early electronic amplifiers (
551:, for maintaining water at a constant level, invented in 270 BC in
3692:
2815:
2750:
2574:, American Scientist, Vol. 45, No. 4 (SEPTEMBER 1957), pp. 343-371
2072:
to portray the information feedback at work in a system. The word
1863:
1732:
1621:
1409:
1305:
to keep the face of the windmill pointing into the wind. In 1787,
1182:
711:
As an example of negative feedback, the diagram might represent a
696:
688:
493:
885:
This confusion may arise because feedback can be used to provide
1091:
593:
3696:
3333:
For an analysis of desensitization in the system pictured, see
2356:
Ramaprasad, Arkalgud (1983). "On the definition of feedback".
2120:
Feedback Systems: An Introduction for Scientists and Engineers
1895:
529:
Feedback Systems: An Introduction for Scientists and Engineers
1203:
loop whereby melting snow exposes more dark ground (of lower
513:
that forms a circuit or loop. The system can then be said to
1946: – Howling caused by a circular path in an audio system
1761:. Latches and flip-flops are fundamental building blocks of
1757:
have one or two outputs. It is the basic storage element in
1509:
Electronic feedback loops are used to control the output of
1207:), which in turn absorbs heat and causes more snow to melt.
972:
Feedback can give rise to incredibly complex behaviors. The
615:
used the term "feed-back" as a noun to refer to (undesired)
2279:, Nobel Lecture, 11 December 1909. Retrieved 19 March 2012.
1785:
Flip-flops can be either simple (transparent or opaque) or
585:
of their production. Early steam engines employed a purely
2046:"Chapter 9: Information feedback and causal loop diagrams"
1282:
was used to regulate the flow of water in Greek and Roman
3186:
in which a negative sign is included in the feedback loop
2997:"Allosteric controls of amphilbolic pathways in bacteria"
1940: – Practice in the field of learning and achievement
1847:
Feedback is also a useful design principle for designing
3281:
Basic Electronics: Devices, Circuits and IT Fundamentals
2002: – Process of repeating items in a self-similar way
565:
were used to regulate the distance and pressure between
3668:
New Issues and Paradigms in Research on Social Dilemmas
3254:. Boca Raton, FL, USA: CRC Press. pp. 13.1–13.14.
1911:
1696:, to distinguish it from an audio frequency oscillator.
3460:
Garg, Rakesh Kumar; Ashish Dixit; Pavan Yadav (2008).
2695:"Feedback for physicists: A tutorial essay on control"
1309:
regulated the rotation speed of a windmill by using a
1286:; similar float valves are used to regulate fuel in a
547:
The first ever known artificial feedback device was a
2732:
Sagawa, Takahiro; Ueda, Masahito (26 February 2008).
2392:. Baltimore, MD, US: Johns Hopkins University Press.
2008: – Tendency to oscillate at certain frequencies
1673:, and the sounds produced by electronic beepers and
4101:
4048:
3990:
3927:
3894:
3826:
3751:
3730:
3337:"§5.3.1 Effect of feedback on parameter variations"
3221:
Journal of the American Society for Naval Engineers
1426:The use of feedback is widespread in the design of
1394:but mechanical feedback was replaced by electronic
1254:errors, and the derivative term is a prediction of
1187:
Some effects of global warming can either enhance (
3589:
2076:refers to cause-and-effect relationships. The word
1290:and also used to regulate tank water level in the
3296:If the feedback signal reduces the input signal,
2277:"Electrical oscillations and wireless telegraphy"
1710:(RF) range of about 100 kHz to 100 GHz.
905:component. As Connellan and Zemke (1993) put it:
693:An example of a negative feedback loop with goals
3428:
3426:
3424:
3422:
1699:An audio oscillator produces frequencies in the
1250:error, the integral term on the accumulation of
2799:"Thermodynamics of feedback controlled systems"
2421:H.S. Black, "Stabilized feed-back amplifiers",
928:
916:feedback tells us how good, bad or indifferent.
907:
745:
737:
650:
519:
3252:Circuit Analysis and Feedback Amplifier Theory
1591:circuits for volatile storage of information.
3708:
3343:. Pearson Education India. pp. 134–135.
2351:
2349:
2347:
2204:Maxwell, James Clerk (1868). "On Governors".
2114:Karl Johan Åström; Richard M. Murray (2008).
1266:For feedback in the educational context, see
1242:using a control-loop feedback mechanism is a
921:Limitations of negative and positive feedback
475:
8:
3390:
3388:
3123:"The Study of Earth as an Integrated System"
2241:HH Cole, "Improvement in Fluting-Machines",
2181:Designing Kinetics for Architectural Facades
1996: – Incentive that has a contrary result
1669:, clock signals that regulate computers and
1521:if no output feedback is being employed and
1498:. Design to ensure stability often involves
1398:once small, robust and powerful single-chip
3439:. New Age International. pp. 224–225.
3436:Electronics (fundamentals And Applications)
2295:A history of control engineering, 1800–1930
1680:Oscillators are often characterized by the
3715:
3701:
3693:
3644:. Chapter 18: Games as Cybernetic Systems.
2447:Proceedings of the Royal Society of London
2433:
2431:
2425:, vol. 53, pp. 114–120, January 1934.
2381:
2379:
2287:
2285:
2206:Proceedings of the Royal Society of London
1594:The loud squeals that sometimes occurs in
1538:astable circuits, which act as oscillators
1332:. Steam engines also use float valves and
482:
468:
38:
3020:
2936:
2887:
2814:
2749:
2458:
2122:. Princeton University Press. p. 1.
1970: – Most basic type of physical force
1706:An RF oscillator produces signals in the
912:feedback tells us how much and how many.
756:Even before these terms were being used,
3490:Digital electronics and design with VHDL
2319:
2317:
2025: – Unforeseen outcomes of an action
1459:; otherwise, the feedback is said to be
1258:error, based on current rate of change.
967:
680:
527:Karl Johan Åström and Richard M.Murray,
3547:J. L. Hellerstein; Y. Diao; S. Parekh;
2797:Cao, F. J.; Feito, M. (10 April 2009).
2559:Circuit Theory of Linear Noisy Networks
2544:Charles S. Carver, Michael F. Scheier:
2036:
1703:range, about 16 Hz to 20 kHz.
48:
41:
3523:(EE 42/100 Lecture 24 from Berkeley)
3284:. PHI Learning Pvt. Ltd. p. 191.
2627:Introduction to Bioregulatory Medicine
2478:from the original on 26 December 2010.
1561:reduction or to establish a specified
1071:do not imply that the feedback causes
3553:Feedback Control of Computing Systems
3248:"Chapter 13: General feedback theory"
3133:from the original on 2 November 2016.
2572:The Experimental Analysis of Behavior
2557:Hermann A Haus and Richard B. Adler,
1774:, and such a circuit is described as
1324:in 1788 to regulate the speed of his
7:
3368:"Negative Feedback & Distortion"
2868:Cytokine & Growth Factor Reviews
2504:. New York: Doubleday. p. 424.
2340:from the original on 23 August 2000.
2174:
2172:
1336:as mechanical regulation devices. A
3096:Scheff, Thomas (2 September 2009).
2929:10.20892/j.issn.2095-3941.2017.0029
2693:Bechhoefer, John (31 August 2005).
1818:. From a software perspective, the
1156:hypothalamic–pituitary–adrenal axis
3871:Evolutionary developmental biology
3233:10.1111/j.1559-3584.1922.tb04958.x
3154:from the original on 21 July 2022.
2621:Alta Smit; Arturo O'Byrne (2011).
2546:On the Self-Regulation of Behavior
2155:. Johns Hopkins University Press.
1874:input and a video output, e.g., a
729:the "feed-back" action is positive
229:Evolutionary developmental biology
25:
3596:. New York: Basic Books. p.
2548:Cambridge University Press, 2001
964:Mathematics and dynamical systems
604:and the mathematics of feedback.
573:since the 17th century. In 1788,
3680:
3493:. Morgan Kaufmann. p. 329.
3098:"The Emotional/Relational World"
1899:
1870:. It involves a loop between a
1244:proportional-integral-derivative
1238:The most common general-purpose
701:A positive feedback loop example
4005:Ordinary differential equations
3466:. Firewall Media. p. 280.
2911:Vlahopoulos, SA (August 2017).
1657:(DC) from a power supply to an
1502:to control the location of the
1340:of Watt's governor was done by
396:Ordinary differential equations
4063:Partial differential equations
2768:10.1103/PhysRevLett.100.080403
2327:An introduction to cybernetics
1328:was one factor leading to the
667:Positive and negative feedback
267:Partial differential equations
1:
3403:. McGraw-Hill. Archived from
3164:
3058:10.1016/S0022-2836(61)80072-7
2917:Cancer Biology & Medicine
2880:10.1016/j.cytogfr.2015.06.001
2438:Maxwell, James Clerk (1868).
1534:are widely used and include:
3670:, New York: Springer, 2008.
3650:, Malkov A., Khaltourina D.
3588:Hofstadter, Douglas (2007).
3172:Dynamics of Feedback Systems
3013:10.1128/MMBR.34.1.20-39.1970
2052:. Island Press. pp. 99
1628:op-amp relaxation oscillator
1496:gain margin and phase margin
1201:ice–albedo positive feedback
3813:Particle swarm optimization
3320:P. Horowitz & W. Hill,
2528:, McGraw Hill/Irwin, 2000.
1645:electronic signal, often a
1525:if feedback is being used.
1484:Nyquist stability criterion
1117:, which were identified by
1113:are used to create genetic
116:Particle swarm optimization
4218:
4058:Reaction-diffusion systems
3783:Self-organized criticality
3487:Volnei A. Pedroni (2008).
3433:Chattopadhyay, D. (2006).
3395:Snelgrove, Martin (2011).
3372:learnabout-electronics.org
2974:10.1016/j.cyto.2016.01.021
2833:10.1103/PhysRevE.79.041118
1974:Human–computer interaction
1889:
1840:
1829:
1641:that produces a periodic,
1231:
1214:
1176:
1029:
1023:
979:
670:
263:Reaction–diffusion systems
92:Self-organized criticality
29:
3841:Artificial neural network
3335:S.K Bhattacharya (2011).
2995:Sanwal, BD (March 1970).
2719:10.1103/RevModPhys.77.783
2699:Reviews of Modern Physics
2386:David A. Mindell (2002).
2116:"§1.1: What is feedback?"
1886:Human resource management
1396:engine management systems
619:between components of an
204:Artificial neural network
32:Feedback (disambiguation)
3919:Evolutionary game theory
3846:Evolutionary computation
3778:Collective consciousness
3555:. John Wiley & Sons.
2050:Modeling the Environment
1690:low-frequency oscillator
1684:of their output signal:
1096:gene regulatory networks
658:translated into action.
455:Evolutionary game theory
345:Second-order cybernetics
209:Evolutionary computation
125:Collective consciousness
18:Electronic feedback loop
3937:Social network analysis
3876:Artificial intelligence
3808:Ant colony optimization
3768:Collective intelligence
2738:Physical Review Letters
2498:Peter M. Senge (1990).
2292:Stuart Bennett (1979).
2261:accessed 23 March 2012.
2259:US Patent 47,769 (1865)
2245:accessed 23 March 2012.
2243:US Patent 55,469 (1866)
2179:Moloney, Jules (2011).
2068:This chapter describes
2023:Unintended consequences
1968:Fundamental interaction
1667:television transmitters
1334:pressure release valves
1179:Climate change feedback
936:Other types of feedback
893:, and often has both a
233:Artificial intelligence
147:Social network analysis
112:Ant colony optimization
84:Collective intelligence
4197:Management cybernetics
4068:Dissipative structures
3909:Rational choice theory
3519:5 October 2016 at the
3514:Latches and Flip Flops
3341:Linear Control Systems
3322:The Art of Electronics
3184:negative feedback loop
3174:, New York: J. Wiley.
2460:10.1098/rspl.1867.0055
2423:Electrical Engineering
2333:. Chapman & Hall.
2324:W. Ross Ashby (1957).
2275:Karl Ferdinand Braun,
2218:10.1098/rspl.1867.0055
1908:This section is empty.
1745:
1729:Latches and flip-flops
1653:. Oscillators convert
1630:
1500:frequency compensation
1423:
1406:Electronic engineering
1278:In ancient times, the
1274:Mechanical engineering
1223:state space (controls)
1196:
1026:Biological interaction
977:
933:
918:
754:
741:
702:
694:
686:
655:
533:
499:
446:Rational choice theory
271:Dissipative structures
3881:Evolutionary robotics
3798:Agent-based modelling
3278:Santiram Kal (2009).
3246:Wai-Kai Chen (2005).
2629:. Thieme. p. 6.
2370:10.1002/bs.3830280103
2134:Online version found
1892:performance appraisal
1843:User interface design
1837:User interface design
1736:
1723:relaxation oscillator
1635:electronic oscillator
1625:
1567:asymptotic gain model
1413:
1392:vacuum timing advance
1338:mathematical analysis
1330:Industrial Revolution
1232:Further information:
1186:
1149:Allosteric regulation
971:
849:discrepancy-enhancing
772:of the same quality.
762:centrifugal governors
700:
692:
684:
563:Centrifugal governors
497:
374:Theory of computation
237:Evolutionary robotics
104:Agent-based modelling
4040:Coupled map lattices
4000:Time series analysis
3942:Small-world networks
3689:at Wikimedia Commons
3656:Moscow: URSS, 2006.
2070:causal loop diagrams
2044:Andrew Ford (2010).
1826:Software Development
1780:finite-state machine
1369:Elmer Ambrose Sperry
1318:centrifugal governor
1311:centrifugal pendulum
1138:predator-prey cycles
1058:insulin oscillations
853:discrepancy-reducing
733:Harold Stephen Black
725:regenerative circuit
613:Karl Ferdinand Braun
587:reciprocating motion
425:Coupled map lattices
391:Time series analysis
151:Small-world networks
30:For other uses, see
4202:Electronic feedback
4020:Population dynamics
3914:Bounded rationality
3856:Genetic programming
3592:I Am a Strange loop
2825:2009PhRvE..79d1118C
2760:2008PhRvL.100h0403S
2711:2005RvMP...77..783B
2664:2009JPCA..113...19W
2012:Stability criterion
1938:Corrective feedback
1763:digital electronics
1659:alternating current
1430:components such as
1420:unilateral elements
1416:ideal block diagram
1402:became affordable.
1375:designed the first
1355:John McFarlane Gray
1342:James Clerk Maxwell
1297:The Dutch inventor
1268:corrective feedback
1227:full state feedback
758:James Clerk Maxwell
637:The development of
598:James Clerk Maxwell
450:Bounded rationality
408:Population dynamics
317:Conversation theory
217:Genetic programming
142:Scale-free networks
74:Collective behavior
4166:Computation theory
4161:Information theory
4116:Operationalization
3992:Nonlinear dynamics
3904:Prisoner's dilemma
3851:Genetic algorithms
2623:"Bipolar feedback"
2358:Behavioral Science
1994:Perverse incentive
1746:
1639:electronic circuit
1631:
1506:of the amplifier.
1424:
1373:Sperry Corporation
1197:
1193:negative feedbacks
1189:positive feedbacks
978:
784:the change of the
703:
695:
687:
621:electronic circuit
500:
441:Prisoner's dilemma
386:Nonlinear dynamics
341:Operationalization
337:Information theory
213:Genetic algorithms
4174:
4173:
4078:Cellular automata
4050:Pattern formation
3982:Adaptive networks
3773:Collective action
3743:Self-organization
3685:Media related to
3607:978-0-465-03079-8
3500:978-0-12-374270-4
3463:Basic Electronics
3446:978-81-224-1780-7
3146:Technical Summary
2803:Physical Review E
2672:10.1021/jp804420g
2561:, MIT Press, 1959
2534:978-0-07-238915-9
2524:John D. Sterman,
2511:978-0-385-26094-7
2305:978-0-906048-07-8
2162:978-0-8018-3939-9
1928:
1927:
1876:television screen
1868:acoustic feedback
1778:. When used in a
1743:D-type flip flops
1573:Positive feedback
1549:Negative feedback
1513:devices, such as
1494:to determine the
1456:negative feedback
1442:elements such as
1299:Cornelius Drebbel
949:chaotic behaviors
677:Positive feedback
673:Negative feedback
581:, for use in the
492:
491:
279:Cellular automata
253:Pattern formation
184:Adaptive networks
88:Collective action
57:Self-organization
16:(Redirected from
4209:
4088:Self-replication
3977:Dynamic networks
3866:Machine learning
3793:Phase transition
3717:
3710:
3703:
3694:
3684:
3624:Katie Salen and
3612:
3611:
3595:
3585:
3579:
3578:
3574:
3568:
3567:
3563:
3557:
3556:
3544:
3538:
3537:
3533:
3527:
3511:
3505:
3504:
3484:
3478:
3477:
3457:
3451:
3450:
3430:
3417:
3416:
3414:
3412:
3392:
3383:
3382:
3380:
3378:
3364:
3358:
3357:
3331:
3325:
3318:
3312:
3309:
3303:
3302:
3275:
3269:
3268:
3243:
3237:
3236:
3216:
3210:
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3208:
3197:
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3189:
3169:
3166:
3161:
3155:
3141:
3135:
3134:
3119:
3113:
3112:
3110:
3108:
3102:Psychology Today
3093:
3087:
3084:
3078:
3077:
3041:
3035:
3034:
3024:
2992:
2986:
2985:
2957:
2951:
2950:
2940:
2908:
2902:
2901:
2891:
2859:
2853:
2852:
2818:
2794:
2788:
2787:
2753:
2729:
2723:
2722:
2690:
2684:
2683:
2652:J. Phys. Chem. A
2647:
2641:
2640:
2618:
2612:
2602:
2596:
2581:
2575:
2568:
2562:
2555:
2549:
2542:
2536:
2522:
2516:
2515:
2495:
2489:
2486:
2480:
2479:
2477:
2462:
2444:
2435:
2426:
2419:
2413:
2410:
2404:
2403:
2383:
2374:
2373:
2353:
2342:
2341:
2339:
2332:
2321:
2312:
2309:
2289:
2280:
2268:
2262:
2252:
2246:
2236:
2230:
2229:
2201:
2195:
2194:
2176:
2167:
2166:
2145:
2139:
2133:
2111:
2105:
2104:
2102:
2100:
2095:. MerriamWebster
2089:
2083:
2082:
2041:
1988:Optical feedback
1980:Low-key feedback
1923:
1920:
1910:You can help by
1903:
1896:
1776:sequential logic
1759:sequential logic
1400:microcontrollers
1381:Nicolas Minorsky
1361:coined the word
1044:systems such as
982:Dynamical system
833:self-reinforcing
750:
607:The verb phrase
531:
511:cause-and-effect
484:
477:
470:
361:Systems thinking
287:Self-replication
225:Machine learning
179:Dynamic networks
100:Phase transition
39:
21:
4217:
4216:
4212:
4211:
4210:
4208:
4207:
4206:
4177:
4176:
4175:
4170:
4136:System dynamics
4097:
4083:Spatial ecology
4044:
3986:
3972:Systems biology
3923:
3890:
3861:Artificial life
3831:
3822:
3818:Swarm behaviour
3803:Synchronization
3763:Social dynamics
3754:
3747:
3726:
3724:Complex systems
3721:
3677:
3621:
3619:Further reading
3616:
3615:
3608:
3587:
3586:
3582:
3576:
3575:
3571:
3565:
3564:
3560:
3546:
3545:
3541:
3535:
3534:
3530:
3521:Wayback Machine
3512:
3508:
3501:
3486:
3485:
3481:
3474:
3459:
3458:
3454:
3447:
3432:
3431:
3420:
3410:
3408:
3407:on 19 July 2013
3394:
3393:
3386:
3376:
3374:
3366:
3365:
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3328:
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3315:
3310:
3306:
3292:
3277:
3276:
3272:
3262:
3245:
3244:
3240:
3218:
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3213:
3206:
3199:
3198:
3194:
3187:
3167:
3162:
3158:
3142:
3138:
3121:
3120:
3116:
3106:
3104:
3095:
3094:
3090:
3085:
3081:
3043:
3042:
3038:
2994:
2993:
2989:
2959:
2958:
2954:
2910:
2909:
2905:
2861:
2860:
2856:
2796:
2795:
2791:
2731:
2730:
2726:
2692:
2691:
2687:
2649:
2648:
2644:
2637:
2620:
2619:
2615:
2603:
2599:
2595:(1992) page 123
2582:
2578:
2569:
2565:
2556:
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2539:
2523:
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2496:
2492:
2487:
2483:
2475:
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2420:
2416:
2411:
2407:
2400:
2385:
2384:
2377:
2355:
2354:
2345:
2337:
2330:
2323:
2322:
2315:
2306:
2291:
2290:
2283:
2269:
2265:
2253:
2249:
2237:
2233:
2203:
2202:
2198:
2191:
2178:
2177:
2170:
2163:
2147:
2146:
2142:
2130:
2113:
2112:
2108:
2098:
2096:
2091:
2090:
2086:
2064:
2043:
2042:
2038:
2033:
2028:
1933:
1924:
1918:
1915:
1894:
1888:
1857:
1849:user interfaces
1845:
1839:
1834:
1832:Software review
1828:
1807:
1731:
1708:radio frequency
1620:
1575:
1551:
1438:, and stateful
1408:
1316:The use of the
1276:
1264:
1236:
1219:
1213:
1181:
1175:
1173:Climate science
1038:
1028:
1022:
1014:Maxwell's demon
1009:
996:
980:Main articles:
966:
961:
938:
923:
837:self-correcting
778:
748:
679:
671:Main articles:
669:
664:
579:Matthew Boulton
542:economic theory
538:
532:
526:
488:
459:
458:
457:
452:
448:
443:
438:
428:
427:
422:
418:
414:
410:
406:
402:
398:
393:
388:
378:
377:
376:
371:
367:
363:
359:
357:Systems science
355:
353:System dynamics
351:
347:
343:
339:
335:
331:
327:
323:
319:
314:
309:
295:
294:
289:
285:
283:Spatial ecology
281:
277:
273:
269:
265:
260:
255:
245:
244:
239:
235:
231:
227:
223:
221:Artificial life
219:
215:
211:
206:
201:
187:
186:
181:
177:
175:Systems biology
173:
169:
165:
161:
157:
153:
149:
144:
139:
129:
128:
127:
122:
120:Swarm behaviour
118:
114:
110:
108:Synchronization
106:
102:
98:
94:
90:
86:
81:
79:Social dynamics
76:
66:
65:
64:
59:
43:Complex systems
35:
28:
23:
22:
15:
12:
11:
5:
4215:
4213:
4205:
4204:
4199:
4194:
4192:Control theory
4189:
4179:
4178:
4172:
4171:
4169:
4168:
4163:
4158:
4153:
4148:
4143:
4138:
4133:
4128:
4126:Self-reference
4123:
4118:
4113:
4107:
4105:
4103:Systems theory
4099:
4098:
4096:
4095:
4090:
4085:
4080:
4075:
4070:
4065:
4060:
4054:
4052:
4046:
4045:
4043:
4042:
4037:
4032:
4030:Multistability
4027:
4022:
4017:
4012:
4007:
4002:
3996:
3994:
3988:
3987:
3985:
3984:
3979:
3974:
3969:
3964:
3959:
3954:
3949:
3944:
3939:
3933:
3931:
3925:
3924:
3922:
3921:
3916:
3911:
3906:
3900:
3898:
3892:
3891:
3889:
3888:
3883:
3878:
3873:
3868:
3863:
3858:
3853:
3848:
3843:
3837:
3835:
3824:
3823:
3821:
3820:
3815:
3810:
3805:
3800:
3795:
3790:
3788:Herd mentality
3785:
3780:
3775:
3770:
3765:
3759:
3757:
3749:
3748:
3746:
3745:
3740:
3734:
3732:
3728:
3727:
3722:
3720:
3719:
3712:
3705:
3697:
3691:
3690:
3676:
3675:External links
3673:
3672:
3671:
3664:
3645:
3626:Eric Zimmerman
3620:
3617:
3614:
3613:
3606:
3580:
3569:
3558:
3539:
3528:
3506:
3499:
3479:
3473:978-8131803028
3472:
3452:
3445:
3418:
3384:
3359:
3349:
3326:
3313:
3304:
3290:
3270:
3260:
3238:
3227:(2): 280–309.
3211:
3192:
3156:
3136:
3129:. NASA. 2016.
3114:
3088:
3079:
3052:(3): 318–356.
3036:
3001:Bacteriol. Rev
2987:
2952:
2923:(3): 254–270.
2903:
2874:(4): 389–403.
2854:
2789:
2724:
2705:(3): 783–836.
2685:
2642:
2635:
2613:
2597:
2593:978-0306437465
2576:
2563:
2550:
2537:
2517:
2510:
2490:
2481:
2440:"On Governors"
2427:
2414:
2405:
2398:
2375:
2343:
2313:
2304:
2281:
2263:
2247:
2231:
2196:
2190:978-0415610346
2189:
2168:
2161:
2140:
2128:
2106:
2084:
2062:
2035:
2034:
2032:
2029:
2027:
2026:
2020:
2014:
2009:
2003:
1997:
1991:
1985:
1984:
1983:
1971:
1965:
1959:
1953:
1947:
1944:Audio feedback
1941:
1934:
1932:
1929:
1926:
1925:
1919:September 2020
1906:
1904:
1890:Main article:
1887:
1884:
1866:equivalent of
1860:Video feedback
1856:
1855:Video feedback
1853:
1841:Main article:
1838:
1835:
1830:Main article:
1827:
1824:
1806:
1803:
1730:
1727:
1712:
1711:
1704:
1697:
1655:direct current
1619:
1616:
1608:audio feedback
1574:
1571:
1550:
1547:
1546:
1545:
1542:
1539:
1531:multivibrators
1407:
1404:
1385:PID controller
1275:
1272:
1263:
1260:
1234:PID controller
1217:Control theory
1215:Main article:
1212:
1211:Control theory
1209:
1191:) or inhibit (
1177:Main article:
1174:
1171:
1133:consumption).
1127:feedback loops
1119:François Jacob
1081:mirror neurons
1024:Main article:
1021:
1018:
1008:
1005:
994:Control theory
974:Mandelbrot set
965:
962:
960:
957:
937:
934:
922:
919:
821:
820:
815:(positive) or
797:
792:(positive) or
777:
774:
713:cruise control
668:
665:
663:
660:
602:control theory
537:
534:
524:
490:
489:
487:
486:
479:
472:
464:
461:
460:
439:
434:
433:
430:
429:
416:Multistability
389:
384:
383:
380:
379:
349:Self-reference
310:
303:Systems theory
301:
300:
297:
296:
256:
251:
250:
247:
246:
202:
193:
192:
189:
188:
140:
135:
134:
131:
130:
96:Herd mentality
77:
72:
71:
68:
67:
60:
55:
54:
51:
50:
46:
45:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
4214:
4203:
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4198:
4195:
4193:
4190:
4188:
4185:
4184:
4182:
4167:
4164:
4162:
4159:
4157:
4154:
4152:
4149:
4147:
4144:
4142:
4139:
4137:
4134:
4132:
4131:Goal-oriented
4129:
4127:
4124:
4122:
4119:
4117:
4114:
4112:
4109:
4108:
4106:
4104:
4100:
4094:
4093:Geomorphology
4091:
4089:
4086:
4084:
4081:
4079:
4076:
4074:
4071:
4069:
4066:
4064:
4061:
4059:
4056:
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4053:
4051:
4047:
4041:
4038:
4036:
4033:
4031:
4028:
4026:
4023:
4021:
4018:
4016:
4013:
4011:
4008:
4006:
4003:
4001:
3998:
3997:
3995:
3993:
3989:
3983:
3980:
3978:
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3718:
3713:
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3699:
3698:
3695:
3688:
3683:
3679:
3678:
3674:
3669:
3665:
3663:
3662:5-484-00559-0
3659:
3655:
3654:
3649:
3646:
3643:
3642:0-262-24045-9
3639:
3635:
3631:
3630:Rules of Play
3627:
3623:
3622:
3618:
3609:
3603:
3599:
3594:
3593:
3584:
3581:
3573:
3570:
3562:
3559:
3554:
3550:
3549:D. M. Tilbury
3543:
3540:
3532:
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3526:
3522:
3518:
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3369:
3363:
3360:
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3350:9788131759523
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3323:
3317:
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3305:
3301:
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3291:9788120319523
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3283:
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3267:
3264:. 423825181.
3263:
3261:9781420037272
3257:
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3180:0-471-27822-X
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2809:(4): 041118.
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2800:
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2646:
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2638:
2636:9783131469717
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2610:0-8144-7824-7
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2399:9780801868955
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2227:
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2186:
2183:. Routledge.
2182:
2175:
2173:
2169:
2164:
2158:
2154:
2150:
2144:
2141:
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2131:
2129:9781400828739
2125:
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2117:
2110:
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2088:
2085:
2081:
2079:
2075:
2071:
2065:
2063:9781610914253
2059:
2055:
2051:
2047:
2040:
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2030:
2024:
2021:
2018:
2015:
2013:
2010:
2007:
2004:
2001:
1998:
1995:
1992:
1989:
1986:
1981:
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1781:
1777:
1773:
1772:
1766:
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1760:
1755:
1751:
1748:A latch or a
1744:
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1728:
1726:
1724:
1719:
1717:
1709:
1705:
1702:
1698:
1695:
1691:
1687:
1686:
1685:
1683:
1678:
1676:
1672:
1671:quartz clocks
1668:
1664:
1660:
1656:
1652:
1648:
1644:
1640:
1636:
1629:
1624:
1617:
1615:
1613:
1609:
1606:are known as
1605:
1601:
1597:
1596:audio systems
1592:
1590:
1585:
1581:
1572:
1570:
1568:
1564:
1560:
1556:
1548:
1543:
1540:
1537:
1536:
1535:
1533:
1532:
1526:
1524:
1520:
1516:
1512:
1507:
1505:
1501:
1497:
1493:
1490:developed by
1489:
1485:
1481:
1477:
1476:Harry Nyquist
1473:
1471:
1466:
1462:
1458:
1457:
1451:
1449:
1445:
1441:
1440:logic circuit
1437:
1433:
1429:
1421:
1417:
1412:
1405:
1403:
1401:
1397:
1393:
1388:
1386:
1382:
1378:
1374:
1370:
1366:
1365:
1360:
1359:Joseph Farcot
1356:
1352:
1351:
1350:Great Eastern
1345:
1343:
1339:
1335:
1331:
1327:
1323:
1319:
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1312:
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1304:
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1259:
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1230:
1228:
1224:
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1164:
1159:
1157:
1152:
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1141:
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1134:
1132:
1128:
1124:
1123:Jacques Monod
1120:
1116:
1112:
1109:
1105:
1104:Lac repressor
1101:
1097:
1093:
1088:
1084:
1082:
1078:
1074:
1070:
1066:
1061:
1059:
1055:
1051:
1047:
1043:
1037:
1033:
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1019:
1017:
1015:
1006:
1004:
1002:
1001:edge of chaos
995:
991:
990:Edge of chaos
987:
983:
975:
970:
963:
958:
956:
952:
950:
945:
942:
935:
932:
927:
920:
917:
915:
911:
906:
904:
903:
898:
897:
892:
888:
883:
881:
880:
875:
874:
873:reinforcement
870:
866:
862:
858:
854:
850:
846:
842:
838:
834:
830:
826:
818:
814:
810:
806:
802:
798:
795:
791:
787:
783:
782:
781:
775:
773:
771:
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759:
753:
744:
740:
736:
734:
730:
726:
721:
719:
714:
709:
706:
699:
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683:
678:
674:
666:
661:
659:
654:
649:
647:
642:
640:
635:
633:
629:
624:
622:
618:
614:
610:
605:
603:
599:
595:
590:
588:
584:
583:steam engines
580:
576:
572:
568:
564:
560:
558:
554:
550:
545:
543:
535:
530:
523:
518:
516:
512:
508:
504:
496:
485:
480:
478:
473:
471:
466:
465:
463:
462:
456:
453:
451:
447:
442:
437:
432:
431:
426:
423:
421:
417:
413:
409:
405:
401:
397:
392:
387:
382:
381:
375:
372:
370:
366:
362:
358:
354:
350:
346:
342:
338:
334:
330:
329:Goal-oriented
326:
322:
318:
313:
308:
304:
299:
298:
293:
292:Geomorphology
290:
288:
284:
280:
276:
272:
268:
264:
259:
254:
249:
248:
243:
240:
238:
234:
230:
226:
222:
218:
214:
210:
205:
200:
196:
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185:
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168:
164:
160:
156:
152:
148:
143:
138:
133:
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126:
123:
121:
117:
113:
109:
105:
101:
97:
93:
89:
85:
80:
75:
70:
69:
63:
58:
53:
52:
47:
44:
40:
37:
33:
19:
4120:
3957:Graph theory
3886:Evolvability
3667:
3652:
3648:Korotayev A.
3629:
3591:
3583:
3572:
3561:
3552:
3542:
3531:
3524:
3509:
3489:
3482:
3462:
3455:
3435:
3409:. Retrieved
3405:the original
3400:
3397:"Oscillator"
3375:. Retrieved
3371:
3362:
3354:
3340:
3329:
3321:
3316:
3307:
3297:
3295:
3280:
3273:
3265:
3251:
3241:
3224:
3220:
3214:
3202:
3195:
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3163:A. I. Mees (
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3143:Fig. TS.17,
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2097:. Retrieved
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2017:Strange loop
1962:Feed forward
1916:
1912:adding to it
1907:
1872:video camera
1858:
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1739:ring counter
1720:
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1694:synthesizers
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1555:out of phase
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1492:Hendrik Bode
1482:derived the
1474:
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1284:water clocks
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959:Applications
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910:Quantitative
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242:Evolvability
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4156:Autopoiesis
4151:Cybernetics
4141:Sensemaking
4111:Homeostasis
4073:Percolation
4035:Bifurcation
4010:Phase space
3896:Game theory
3753:Collective
3203:PID Control
3200:Araki, M.,
3168: 1981
2968:: 127–135.
2453:: 270–283.
2212:: 270–283.
1956:Cybernetics
1675:video games
1651:square wave
1643:oscillating
1523:closed loop
1436:oscillators
1418:made up of
1288:carburettor
1280:float valve
1125:in 1961 as
1032:Homeostasis
914:Qualitative
896:qualitative
887:information
841:reinforcing
819:(negative).
796:(negative).
776:Terminology
718:speedometer
639:cybernetics
549:float valve
436:Game theory
420:Bifurcation
400:Phase space
365:Sensemaking
333:Homeostasis
312:Autopoiesis
307:cybernetics
275:Percolation
4181:Categories
3967:Robustness
3947:Centrality
3833:adaptation
3731:Background
3046:J Mol Biol
2093:"feedback"
2031:References
1816:IBM Tivoli
1626:A popular
1618:Oscillator
1604:rock music
1600:PA systems
1584:hysteresis
1580:oscillates
1559:distortion
1515:amplifiers
1511:electronic
1488:Bode plots
1444:flip-flops
1432:amplifiers
1428:electronic
1322:James Watt
1240:controller
1195:) warming.
1163:psychology
1050:ecosystems
1042:biological
1036:Allostasis
1030:See also:
879:punishment
575:James Watt
567:millstones
553:Alexandria
404:Attractors
199:adaptation
171:Robustness
155:Centrality
4015:Attractor
3828:Evolution
3738:Emergence
3634:MIT Press
2841:1539-3755
2816:0805.4824
2776:0031-9007
2751:0710.0956
2149:Otto Mayr
2099:1 January
2006:Resonance
2000:Recursion
1950:Black box
1820:autonomic
1791:flip-flop
1750:flip-flop
1716:inverters
1682:frequency
1647:sine wave
1612:loop gain
1519:open loop
1480:Bell Labs
1470:oscillate
1465:stability
1379:in 1912.
1377:autopilot
1344:in 1868.
1262:Education
1131:metabolic
1108:activator
1100:Repressor
1054:biosphere
1052:, or the
1046:organisms
845:balancing
794:narrowing
571:windmills
515:feed back
195:Evolution
62:Emergence
4187:Feedback
4121:Feedback
3929:Networks
3755:behavior
3687:Feedback
3636:. 2004.
3551:(2004).
3517:Archived
3152:Archived
3131:Archived
3127:nasa.gov
3074:19804795
3066:13718526
2982:26854213
2962:Cytokine
2947:28884042
2898:26119834
2849:19518184
2784:18352605
2680:19072712
2473:Archived
2469:51751195
2364:: 4–13.
2335:Archived
2151:(1989).
1931:See also
1805:Software
1737:A 4-bit
1589:bistable
1461:positive
1448:counters
1307:Tom Mead
1167:hormones
1145:zymology
1111:proteins
1069:negative
1065:positive
891:motivate
869:negative
865:positive
829:negative
825:positive
790:widening
770:decrease
766:increase
617:coupling
525:—
503:Feedback
325:Feedback
258:Fractals
137:Networks
4146:Entropy
3962:Scaling
3411:1 March
3107:10 July
3031:4315011
2938:5570602
2889:4526340
2821:Bibcode
2756:Bibcode
2707:Bibcode
2660:Bibcode
1880:monitor
1862:is the
1812:IBM Db2
1795:latches
1787:clocked
1754:circuit
1371:of the
1303:fantail
1248:present
1115:operons
1020:Biology
1007:Physics
817:unhappy
803:of the
801:valence
628:audions
536:History
369:Variety
321:Entropy
167:Scaling
3952:Motifs
3660:
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2060:
1741:using
1637:is an
1602:, and
1256:future
1205:albedo
1106:) and
992:, and
899:and a
809:effect
805:action
749:
159:Motifs
49:Topics
4025:Chaos
3207:(PDF)
3070:S2CID
2811:arXiv
2746:arXiv
2476:(PDF)
2465:S2CID
2443:(PDF)
2338:(PDF)
2331:(PDF)
2222:JSTOR
1864:video
1771:state
1752:is a
1701:audio
1663:radio
1649:or a
1504:poles
1364:servo
1102:(see
1092:genes
831:with
813:happy
662:Types
646:Ashby
557:Egypt
507:chain
412:Chaos
3830:and
3658:ISBN
3638:ISBN
3602:ISBN
3495:ISBN
3468:ISBN
3441:ISBN
3413:2012
3379:2024
3345:ISBN
3298:i.e.
3286:ISBN
3256:ISBN
3190:..."
3176:ISBN
3109:2013
3062:PMID
3027:PMID
2978:PMID
2943:PMID
2894:PMID
2845:PMID
2837:ISSN
2780:PMID
2772:ISSN
2676:PMID
2631:ISBN
2606:ISBN
2589:ISBN
2530:ISBN
2506:ISBN
2394:ISBN
2300:ISBN
2185:ISBN
2157:ISBN
2136:here
2124:ISBN
2101:2022
2078:loop
2058:ISBN
1814:and
1665:and
1563:gain
1446:and
1347:The
1252:past
1154:The
1121:and
1094:and
1073:good
1067:and
1034:and
867:and
859:and
851:and
843:and
835:and
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799:the
675:and
594:1868
305:and
197:and
3229:doi
3054:doi
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3009:doi
2970:doi
2933:PMC
2925:doi
2884:PMC
2876:doi
2829:doi
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2742:100
2715:doi
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2656:113
2455:doi
2366:doi
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