|
Heterostasis (cybernetics)
''Heterostasis'' is a medical term. It is a neologism coined by Walter Cannon intended to connote an alternative but related meaning to its lexical sibling Homeostasis, which means 'same state'. Any device, organ, system or organism capable of Heterostasis (multistable behavior) can be represented by an abstract state machine composed of a characteristic set of related, interconnected states, linked dynamically by change processes allowing transition between states. Although the term 'Heterostasis' is an obvious rearrangement (by syntactically substituting the prefix 'Hetero-' for its dichotome 'Homeo-', and likewise swapping the semantic reference, from 'same'/'single' to 'different'/'many'), the endocrinologist Hans Selye is generally credited with its invention. An excellent overview of the two concepts is contained in the Cambridge Handbook of Psychophysiology, Chapter 19. Selye's ideas were used by Gunther et al.,Gunther, B., Morgado, E., Jimenez, R.F. (2003Homeostasis to Hete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neologism
A neologism Greek νέο- ''néo''(="new") and λόγος /''lógos'' meaning "speech, utterance"] is a relatively recent or isolated term, word, or phrase that may be in the process of entering common use, but that has not been fully accepted into mainstream language. Neologisms are often driven by changes in culture and technology. In the process of language formation, neologisms are more mature than '' protologisms''. A word whose development stage is between that of the protologism (freshly coined) and neologism (new word) is a ''prelogism''. Popular examples of neologisms can be found in science, fiction (notably science fiction), films and television, branding, literature, jargon, cant, linguistics, the visual arts, and popular culture. Former examples include ''laser'' (1960) from Light Amplification by Stimulated Emission of Radiation; ''robot'' (1941) from Czech writer Karel Čapek's play ''R.U.R. (Rossum's Universal Robots)''; and ''agitprop'' (1930) (a portmanteau of " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walter Cannon
Walter Bradford Cannon (October 19, 1871 – October 1, 1945) was an American physiologist, professor and chairman of the Department of Physiology at Harvard Medical School. He coined the term "fight or flight response", and developed the theory of homeostasis. He popularized his theories in his book ''The Wisdom of the Body'', first published in 1932. Life and career Cannon was born on October 19, 1871, in Prairie du Chien, Wisconsin, the son of Colbert Hanchett Cannon and his wife Wilma Denio. His sister Ida Maud Cannon (1877-1960) became a noted hospital social worker at Massachusetts General Hospital. In his autobiography ''The Way of an Investigator'', Cannon counts himself among the descendants of Jacques de Noyon, a French Canadian explorer and coureur des bois. His Calvinist family was intellectually active, including readings from James Martineau, John Fiske (philosopher), and James Freeman Clarke. Cannon's curiosity also led him to Thomas Henry Huxley, John Tyndall, Geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homeostasis
In biology, homeostasis (British English, British also homoeostasis) Help:IPA/English, (/hɒmɪə(ʊ)ˈsteɪsɪs/) is the state of steady internal, physics, physical, and chemistry, chemical conditions maintained by organism, living systems. This is the condition of optimal functioning for the organism and includes many variables, such as body temperature and fluid balance, being kept within certain pre-set limits (homeostatic range). Other variables include the pH of extracellular fluid, the concentrations of sodium, potassium and calcium ions, as well as that of the blood sugar level, and these need to be regulated despite changes in the environment, diet, or level of activity. Each of these variables is controlled by one or more regulators or homeostatic mechanisms, which together maintain life. Homeostasis is brought about by a natural resistance to change when already in the optimal conditions, and equilibrium is maintained by many regulatory mechanisms: it is thought to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
State Machine
A finite-state machine (FSM) or finite-state automaton (FSA, plural: ''automata''), finite automaton, or simply a state machine, is a mathematical model of computation. It is an abstract machine that can be in exactly one of a finite number of '' states'' at any given time. The FSM can change from one state to another in response to some inputs; the change from one state to another is called a ''transition''. An FSM is defined by a list of its states, its initial state, and the inputs that trigger each transition. Finite-state machines are of two types— deterministic finite-state machines and non-deterministic finite-state machines. A deterministic finite-state machine can be constructed equivalent to any non-deterministic one. The behavior of state machines can be observed in many devices in modern society that perform a predetermined sequence of actions depending on a sequence of events with which they are presented. Simple examples are vending machines, which dispense p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Selye
János Hugo Bruno "Hans" Selye (; hu, Selye János; January 26, 1907 – October 16, 1982) was a pioneering Hungarian-Canadian endocrinologist who conducted important scientific work on the hypothetical non-specific response of an organism to stressors. Although he did not recognize all of the many aspects of glucocorticoids, Selye was aware of their role in the stress response. Charlotte Gerson considers him the first to demonstrate the existence of biological stress. Biography Selye was born in Vienna, Austria-Hungary on January 26, 1907 and grew up in Komárom (the town with Hungarian majority in present day Slovakia was cut by the Treaty of Trianon in 1920). Selye's father was a doctor of Hungarian ethnicity and his mother was Austrian. He became a Doctor of Medicine and Chemistry in Prague in 1929 and went on to do pioneering work in stress and endocrinology at Johns Hopkins University, McGill University, and the Université de Montréal. He was nominated for the Nobel P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allostasis
Allostasis also known as “body budgeting” which Lisa Feldman Barret argues, proposes that efficient regulation requires preparing the body to satisfy the needs before they arise by budgeting those needed resources such as oxygen, insulin etc., as opposed to homeostasis, in which the goal is a steady state. Allostasis, ''stability through variation'', was proposed by Sterling and Eyer in 1988 as a new model of physiological regulation. The goal of every living being is to “find and maintain a steady state for survival” which is achieved through Allostasis and homeostasis. The term Allostasis is used more frequently now since it is more inclusive of the idea that not everything in the body is in a single steady state meaning that there are varying levels of energy. Evolution and Allostasis A second perspective on allostasis is that it is included in the story of how the brain was created. Barret argues, that during evolution “organisms internal systems'' became much ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Servomechanism
In control engineering a servomechanism, usually shortened to servo, is an automatic device that uses error-sensing negative feedback to correct the action of a mechanism. On displacement-controlled applications, it usually includes a built-in encoder or other position feedback mechanism to ensure the output is achieving the desired effect. The term correctly applies only to systems where the feedback or error-correction signals help control mechanical position, speed, attitude or any other measurable variables. For example, an automotive power window control is not a servomechanism, as there is no automatic feedback that controls position—the operator does this by observation. By contrast a car's cruise control uses closed-loop feedback, which classifies it as a servomechanism. Applications Position control A common type of servo provides ''position control''. Commonly, servos are electric, hydraulic, or pneumatic. They operate on the principle of negative feedback, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Servomotor
A servomotor (or servo motor) is a rotary actuator or linear actuator that allows for precise control of angular or linear position, velocity and acceleration. It consists of a suitable motor coupled to a sensor for position feedback. It also requires a relatively sophisticated controller, often a dedicated module designed specifically for use with servomotors. Servomotors are not a specific class of motor, although the term ''servomotor'' is often used to refer to a motor suitable for use in a closed-loop control system. Servomotors are used in applications such as robotics, CNC machine, CNC machinery, and automated manufacturing. Mechanism A servomotor is a closed-loop controller, closed-loop servomechanism that uses position feedback to control its motion and final position. The input to its control is a signal (either analogue or digital) representing the position commanded for the output shaft. The motor is paired with some type of encoder (position), position encoder t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Servomechanisms
In control engineering a servomechanism, usually shortened to servo, is an automatic device that uses error-sensing negative feedback to correct the action of a mechanism. On displacement-controlled applications, it usually includes a built-in encoder or other position feedback mechanism to ensure the output is achieving the desired effect. The term correctly applies only to systems where the feedback or error-correction signals help control mechanical position, speed, attitude or any other measurable variables. For example, an automotive power window control is not a servomechanism, as there is no automatic feedback that controls position—the operator does this by observation. By contrast a car's cruise control uses closed-loop feedback, which classifies it as a servomechanism. Applications Position control A common type of servo provides ''position control''. Commonly, servos are electric, hydraulic, or pneumatic. They operate on the principle of negative feedback, wher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
