What does feedback mean? Feedback in communication

the impact of a controlled process on a control element, leading either to positive feedback (which can transform a stable state into an unstable one) or to negative feedback that stabilizes the state.

Excellent definition

Incomplete definition ↓

FEEDBACK,

the reverse impact of the results of a process on its course or a controlled process on the governing body. O. s. characterizes regulation and management systems in wildlife, society and technology. They distinguish between positive and deny. O. s. If the results of the process strengthen it, then O. s. is positive. When the results of a process weaken its effect, then negation occurs. O. s. Negative O. s. stabilizes the flow of processes. Positive OS, on the contrary, usually leads to accelerated development of processes. In complex systems (for example, social, biological) the definition of types of O. s. difficult and sometimes impossible. Sometimes O. s. in complex systems it is considered as the transfer of information about the course of a process, on the basis of which one or another control action is developed. In this case, O. s. called information. Concept of O. s. as a form of interaction plays an important role in the analysis of the functioning and development of complex control systems in living nature and society, in revealing the structure of the material unity of the world.

Excellent definition

Incomplete definition ↓

Feedback

the reverse impact of the results of a process on its course or a controlled process on the governing body. O. s. characterizes regulation and management systems in wildlife, society and technology. There are positive and negative O. s. If the results of the process strengthen it, then O. s. is positive. When the results of a process weaken its effect, then negative O. s. occurs. Negative O. s. stabilizes the flow of processes. Positive O. s., on the contrary, usually leads to accelerated development of processes and oscillatory processes. In complex systems (for example, social, biological) determination of the types of O. s. difficult and sometimes impossible. O. s. They are also classified according to the nature of the bodies and media through which they are carried out: mechanical (for example, negative O. system, carried out by Watt’s centrifugal regulator (See Centrifugal regulator) in a steam engine); optical (for example, positive feedback, carried out by an optical resonator in a laser); electric, etc. Sometimes O. s. in complex systems it is considered as the transmission of information about the progress of a process, on the basis of which one or another control action is developed. In this case, O. s. called information. Concept of O. s. as a form of interaction plays an important role in the analysis of the functioning and development of complex control systems in living nature and society, in revealing the structure of the material unity of the world.

L. I. Freidin.

Feedback in automatic regulation and control systems, communication in the direction from the output to the input of the considered section of the main chain of influences (information transfer). This section can be either a controlled object or any link of an automatic system (or a set of links). The main chain of influences is a conditionally distinguished chain of signals passing from the input to the output of the automatic system. O. s. forms a path for the transmission of influences in addition to the main chain of influences or any part of it.

Thanks to O. s. the results of the functioning of automatic systems affect the input of the same system or, accordingly, its part, influence the nature of their functioning and the mathematical description of movement. Such systems with a closed chain of influences - closed control systems (See Closed-loop control system) - are characterized by the fact that their input are both external and control influences, i.e. coming from the controlled object to the control device.

Circuit (channel) O.S. may contain one or more links that transform the output signal of the main chain of influences according to a given Algorithm y. Example of a circuit O. s. - a control device (for example, an automatic regulator) that receives the output (real) impact of the controlled object as an input value and compares it with the prescribed (in accordance with the operating algorithm) value. As a result of this comparison, the effect of the control device on the controlled object is formed (see Automatic regulation). Thus, the control object is covered by the O.S. circuit. in the form of a control device, the influence circuit is closed; such O. s. usually called the main one.

O. s. is a fundamental concept of cybernetics (See Cybernetics), especially control theory and information theory; O. s. allows you to monitor and take into account the actual state of the controlled system (i.e., ultimately, the results of the control system) and make appropriate adjustments to its control algorithm. In technical systems, control information about the operation of the controlled object is received through the O.S. circuit. to the operator or automatic control device.

Negative O. s. widely used in closed automatic systems in order to increase stability (stabilization), improve transient processes, reduce sensitivity, etc. (sensitivity is understood as the ratio of an infinitesimal change in the output effect to the infinitesimal input effect that caused it). Positive O. s. enhances the output effect of a link (or system), leads to an increase in sensitivity and, as a rule, to a decrease in stability (often to undamped and divergent oscillations), deterioration of transient processes and dynamic properties, etc.

According to the type of transformation of the impact in the O. s. chain. There are rigid (static), differentiating (flexible, elastic) and integrating systems. Hard O. s. contains only proportional elements and its output effect is proportional to the input (both statically and dynamically - in a certain range of oscillation frequencies). Differentiating connections contain differentiating links (simple, isodromic) and can be astatic (disappearing over time) or with staticism. Connections without statism appear only in dynamics, since in their mathematical model the input effect is not involved, but only its derivatives appear, tending to zero with the end of transient processes. In the composition of the integrating O. s. includes an integrating link that accumulates incoming influences over time.

For systems with OS. The following patterns are true. Proportional link when covering O. s. remains proportional with a new transmission coefficient, increased (against the original) for positive and decreased for negative O. s. A static link of the first order when covered by a rigid negative O. system. remains static of the first order; the time constant and the transmission coefficient change. Integrating link when covered by a rigid negative O. system. turns into static, and when covering isodromic O. with. begins to respond to the derivative (with respect to time) of the input influence. Static link of the first order when covering an isodromic O. with. also reacts to the derivative (with respect to time) of the input influence. When the proportional link of the integrating negative O. is covered. the result is an inertial-differentiating link. If, in this case, the original proportional link has a very large transmission coefficient (compared to the transmission coefficient of an isodromic O. system), then the resulting link approaches the differentiating one in its characteristics.

Lit.: Hammond P.H., Feedback Theory and Its Applications, trans. from English, M., 1961; Wiener N., Cybernetics, trans. from English, M., 1958; him, Cybernetics and Society, trans. from English, M., 1958; Theory of automatic control, parts 1-2, M., 1968-72; Fundamentals of automatic control, 3rd ed., M., 1974.

M. M. Maisel.

Feedback in radio-electronic devices, the effect of a signal from the output of a device on its input. The electrical circuit through which the signal from the output of the device is supplied to the input is called the O.S. circuit. Most often, the device can be represented as an equivalent electrical circuit that has two (input and output) pairs of terminals, and can be characterized by the so-called. transfer function, or transfer function, defined by the ratio of the voltage or current at the output pair of terminals to the voltage or current at the input pair of terminals. Transfer function Fc devices with OS. can be determined from the formula:

Where F 0- device transfer function without O.S.; β - circuit function O. s.; βF 0- loop gain; 1 - βF 0- depth of O. s.

Classification of O. s. O. s. classified mainly by the type of transmission function of the O. s chain. and the relationship between the transmission functions of the O. s. chain. and the device itself, according to the nature of the O. s. circuit, according to the method of connecting the O. s. circuit. to the input and output of the device.

A distinction is made between linear and nonlinear O. s. depending on whether the transmission function of the circuit is linear or nonlinear. If βF 0 - real number and > 0, O.s. is positive; If βF 0- real number and Complex numbers); such O. s. called complex. At Δφ equal to 90°, O. s. sometimes called (purely) reactive. If the chain is complex O. s. contains a delay line (See Delay line), that is, if Δφ is approximately proportional to the oscillation frequency, O. s. called retarded.

According to the method of connecting O. s. circuits. To the input and output of the device, a distinction is made between serial and parallel O.S., if the output of the O.S. circuit. connected in series ( rice. 1 , a, b) or parallel ( rice. 1 , b, d) signal source, and mixed (combined) at the input, if the connection of the circuits is O.S. to the signal source serial-parallel. There are also O. s. by voltage and current, if the voltage or current is at the input of the circuit O. s. proportional to the voltage across the load resistance ( rice. 1 , b, d) or the current in it ( rice. 1 , a, c), and O. s. mixed (combined) at the output, if the connection of the circuits is O. s. to the load (output) resistance in series-parallel. OS, in which only noise and signal distortion occurring in the device are transmitted from the output to the input of the device, called balanced.

Properties and applications of feedback. In a device with positive O. s. with a loop gain ≥ 1, self-oscillations can occur, which is used in various types of electrical oscillation generators. Positive O. s. with βF 0 Electric filter). It also makes it possible to implement in electrical and radio engineering devices elements of electrical circuits that do not exist in the form of physical devices, for example elements with negative capacitance and negative inductance, a gyrator (impedance converter, for example capacitive to inductive) at any operating frequency and elements with electrically controlled parameters (for example, in the form of a reactive lamp (See Reactive lamp)). Sometimes such O. s. used to neutralize unwanted internal oxygen. in electronic devices.

Several O.S. circuits are often used simultaneously in one device. of various nature. An example is a tube amplifier ( rice. 2 ) with a complex frequency-dependent parallel O.S. by voltage, realized by mutual inductance (the so-called transformer O.S.), and negative series O.S. by current carried by a resistor. At a frequency equal to the resonant frequency oscillatory circuit, transformer O. s. becomes positive. If its loop gain

Lit.: Braude G.V., Correction of television and pulse signals, Sat. Art., M., 1967; Tsykin G.S., Amplifier devices, 4th ed., M., 1971.

L. I. Freidin.

Feedback in biology. The existence of regulatory systems with O. s. can be traced at all levels of organization of living things (See Levels of organization of living things) - from molecular to population and biocenotic. The contribution of this mechanism to the automatic maintenance of constancy is especially significant. internal environments body - Homeostasis and, in the activity of the genetic apparatus, endocrine and nervous systems.

Ideas about regulation according to the principle of O. s. appeared in biology a long time ago. Already the first hypothesis about reflex reactions (R. Descartes, 17th century, J. Prochaska, 18th century) contained the premises of this principle. In a clearer form, these ideas were developed in the works of Ch. Bella, I.M. Sechenova and I.P. Pavlova, and later - in the 30-40s. 20th century N. A. Bernstein and P. K. Anokhin. In the form that is most complete and closest to its modern understanding, the principle of O. s. (negative) - as a general principle for all living systems - was formulated by the Russian physiologist N. A. Belov (1912-24) under the name “parallel-cross interaction” and experimentally studied on endocrine organs by M. M. Zavadovsky (See Zavadovsky) , who called it “plus-minus interaction.” Belov showed that negative O. s. - a general principle that ensures a tendency towards equilibrium in any (not only living) systems, but, like Zavadovsky, he believed that the existence of positive O. systems is impossible in living systems. Soviet scientist A. A. Malinovsky demonstrated the presence of all types of oxygen in living systems. and the differences in their adaptive significance were formulated (1945-60). Abroad O. s. in biology began to be widely studied after the appearance of N. Wiener’s book “Cybernetics” in 1948. In the USSR in the 50-60s. 20th century I. I. Shmalhausen successfully applied the concept of O. s. in population genetics.

In living systems one should distinguish between O. s. types of mutual stimulation (positive OS) or suppression in response to stimulation (negative OS), amenable to at least an approximate quantitative assessment, and qualitatively complex OS, when, for example, in Ontogenesis, one organ promotes differentiation another, and the latter, at a new stage, determines the qualitative development of the first. General principles O. s. formulated mainly for relations of the first type. Negative O. s. ensures that the system is maintained in stable equilibrium, because an increase in the impact of the governing body on the object (regulated body, system, process) causes the opposite effect of the object on the governing body. Physiological meaning of negative O. s. lies in the fact that an increase in the controlled variable (for example, the activity of an organ) above a certain limit causes a downward effect on the part of the subsystem associated with it; a sharp decrease in the controlled value causes the opposite effect. With a positive O. s. information about an increase in the controlled value causes a reaction in the subsystem associated with it, ensuring a further increase in this value. In highly organized animals, the activity of the central nervous system normally always includes both necessary condition presence of O. s. Thus, any action of an animal, for example, chasing prey, is accompanied by impulses coming from the central nervous system to the muscles (running, grasping prey), and feedback signals from the senses (vision, proprioceptors, etc.), allowing the results of efforts to be taken into account and corrected due to the course of events.

Combinations of positive and negative O. s. cause an alternative change in physiological states (for example, sleep - wakefulness). Studying the development curve of pathological processes of a non-infectious nature (trophic ulcers, hypertension, manic-depressive psychosis, epilepsy, etc.) allows, based on the result, to determine the most likely type of OS underlying the disease and to limit the study of its etiology and pathogenesis by mechanisms of a certain category. Living objects, as the most advanced self-regulating systems, are rich in various types of oxygen; the study of the latter is very productive for the study of biological phenomena and the establishment of their specificity.

Lit.: Malinovsky A. A., Types of control biological systems and their adaptive significance, in the collection: Problems of Cybernetics, No. 4, M., 1961, p. 151-181; Regulatory mechanisms of the cell, trans. from English, M., 1964; Petrushenko L.A., The principle of feedback, M., 1967: Wiener N., Cybernetics or control and communication in animals and machines, trans. from English, M., 1968; Shmalgauzen I.I., Cybernetic issues of biology, Novosibirsk, 1968.

A. A. Malinovsky.

Rice. 1. Amplifier circuits with various types feedback circuits: a - serial current feedback; b - sequential voltage feedback; c - parallel current feedback; d - parallel voltage feedback. 1 - amplifier of electrical vibrations; 2 - feedback circuit (the arrow shows the direction of signal propagation along the feedback circuit from its input terminals to the output terminals): Z source - impedance of the signal source E source; Z load is the total load resistance of the amplifier.

Rice. 2. Tube amplifier of electrical oscillations with feedback: U in - voltage at the amplifier input; L - electron tube; R- resistor in the lamp cathode circuit; L And WITH- respectively, the inductance and capacitance of the oscillatory circuit in the lamp anode circuit; M- mutual inductance connecting the circuits of the anode and the control grid of the lamp; U out - voltage at the amplifier output; E a is the anode supply voltage.

Big Soviet encyclopedia. - M.: Soviet Encyclopedia. 1969-1978 .

See what “Feedback” is in other dictionaries:

Feedback- Dependence of current impacts on an object on its state caused by previous impacts on the same object. Notes 1. Feedback can be natural (inherent in the object) or artificially organized. 2. Distinguish... ... Technical Translator's Guide

Feedback- Response action, regulatory reaction caused by the situation that has arisen. In group therapy, the facilitator often asks at the end of the episode individual work feedback from group members. The goal may be to obtain additional... ... Great psychological encyclopedia

The impact of the results of the functioning of any system (object) on the nature of this functioning. If the influence of feedback enhances the results of functioning, then such feedback is called positive; if it weakens... Big encyclopedic Dictionary

What is feedback (FE), why is it needed and how to increase the efficiency of your employees through FE.

Three groups of young people performed laboratory conditions the same work, and regardless of the results, one group was encouraged with approval, critical remarks were made to the other group, and the third group was ignored (neither praised nor criticized). As expected, the first group showed the best results, the next in the ranking was the group that was regularly criticized, and the most low level achievements were shown ... by the third group, left without attention.
Feedback- intentional communication to another person about those actions that lead to achieving a goal.

OS features:
* Support and encouragement of actions that lead to success and produce the desired result.
* Changing ineffective behavior
* Motivation
* Learning to learn from past mistakes and failures.
OS target– so that the next time in a similar situation the person acts just as successfully or avoids previously made mistakes.

During our lives we get OS many times. Sometimes it is given directly, sometimes indirectly. Sometimes this OS helps us better learn something new about ourselves. But sometimes feedback leaves us feeling negative and doesn't help us perform or learn better.

How to give Feedback?
Targeted
(It is very important, when giving OS, to call by name, say “you/you” and not “he/she”, eye contact)
Specifically
(Place special emphasis on the fact that the OS is often given “I liked everything.” Everything is nothing!
The best result will be given by being specific - “I liked how you said that time, how you restrained yourself at such and such a moment, how you smiled after this question, your gesture, etc.”)
Short and to the point
(Brevity is the sister of talent; it is very difficult to remember everything, and efficiency detailed analysis of the entire meeting is not always high, a person will still pay attention and remember only a few points, so it is better to focus on one or two stages/directions that will help in the future, as well as on those that need development)
Posts
(Be sure to take notes when giving OS, firstly, not everything is remembered, and secondly, this will increase respect for you on the part of the person to whom you are giving OS, that you listened carefully and took the process seriously. Thirdly, sometimes a person does not realize what exactly and how he says, quotes will help to understand some points, plus they will show that you are not unfounded).

How to receive Feedback?
Seek objectivity
Don't apologize
Don't make excuses
Don't argue
Don't be offended
Make notes
The most important thing when receiving feedback is to remember all your skills as an effective communicator.
After all, the purpose of the OS is not to scold you, not to humiliate you and not to poke you into mistakes, but to help. That’s why you need to accept feedback as help, abstracting from emotions, listening carefully and not just making notes.

The Feedback structure is like a positive sandwich. What is its positivity? Remember the cartoon about Matroskin. So, the structure of the OS is very similar to the most correct sandwich, no matter how you put it, it’s still a sausage on the tongue.
Positive points (what I liked) +
Points for improvement (what to add, what is missing) –
Points to think about (where to move, what to work on, what to build success on) +/-

Happy Feedback.