Dependence of the state of a system on its history
Not to be confused with Hysteria.
Electric displacement field D of a ferroelectric material as the electric field E is first decreased, then increased. The curves form a hysteresis loop.
Hysteresis is the dependence of the state of a system on its history. For example, a magnet may have more than one possible magnetic moment in a given magnetic field, depending on how the field changed in the past. Plots of a single component of the moment often form a loop or hysteresis curve, where there are different values of one variable depending on the direction of change of another variable. This history dependence is the basis of memory in a hard disk drive and the remanence that retains a record of the Earth's magnetic field magnitude in the past. Hysteresis occurs in ferromagnetic and ferroelectric materials, as well as in the deformation of rubber bands and shape-memory alloys and many other natural phenomena. In natural systems, it is often associated with irreversible thermodynamic change such as phase transitions and with internal friction; and dissipation is a common side effect.
Hysteresis can be found in physics, chemistry, engineering, biology, and economics. It is incorporated in many artificial systems: for example, in thermostats and Schmitt triggers, it prevents unwanted frequent switching.
Hysteresis can be a dynamic lag between an input and an output that disappears if the input is varied more slowly; this is known as rate-dependent hysteresis. However, phenomena such as the magnetic hysteresis loops are mainly rate-independent, which makes a durable memory possible.
Systems with hysteresis are nonlinear, and can be mathematically challenging to model. Some hysteretic models, such as the Preisach model (originally applied to ferromagnetism) and the Bouc–Wen model, attempt to capture general features of hysteresis; and there are also phenomenological models for particular phenomena such as the Jiles–Atherton model for ferromagnetism.
It is difficult to define hysteresis precisely. Isaak D. Mayergoyz wrote "...the very meaning of hysteresis varies from one area to another, from paper to paper and from author to author. As a result, a stringent mathematical definition of hysteresis is needed in order to avoid confusion and ambiguity.".[1]
^Mayergoyz, I. D. (2003). Mathematical models of hysteresis and their applications. Amsterdam: Elsevier. p. xiv. ISBN 978-0-12-480873-7. OCLC 162129543.
traverses the path. Many authors restrict the term hysteresis to mean only rate-independent hysteresis. Hysteresis effects can be characterized using the Preisach...
empirical models in hysteresis are Preisach and Jiles-Atherton models. These models allow an accurate modeling of the hysteresis loop and are widely used...
The threshold detector with hysteresis consists of an operational amplifier and a series of resistors that provide hysteresis.: 5 : 7 Like other detectors...
widest available torque range of any of the hysteresis products. Most applications involving powered hysteresis units are in test stand requirements. When...
vector whenever direction is reversed. Deadband is different from hysteresis. With hysteresis, there is no deadband and so the output is always in one direction...
necessary, as M phase initiation is an all-or-nothing event engaging in hysteresis. Hysteresis of Cdk1 activity via cyclin B drives M phase entry by establishing...
In electronics, a Schmitt trigger is a comparator circuit with hysteresis implemented by applying positive feedback to the noninverting input of a comparator...
electromagnetism, the Preisach model of hysteresis is a model of magnetic hysteresis. Originally, it generalized hysteresis as the relationship between the magnetic...
ice. Thermal hysteresis is easily measured in the lab with a nanolitre osmometer. Organisms differ in their values of thermal hysteresis. The maximum...
tens of microseconds. Since op-amps do not have any internal hysteresis, an external hysteresis network is always necessary for slow moving input signals...
metals. Hysteresis heating and Chain scission Fatigue in polymers, controlled by cyclical loading, is caused by two general mechanisms: hysteresis heating...
The time loop or temporal loop is a plot device in fiction whereby characters re-experience a span of time which is repeated, sometimes more than once...
dynamical system exhibits chaotic hysteresis if it simultaneously exhibits chaotic dynamics (chaos theory) and hysteresis. As the latter involves the persistence...
cobalt steel. These are manufactured in permanent magnet, reluctance and hysteresis designs: A permanent-magnet synchronous motor (PMSM) uses permanent magnets...
to hysteresis and eddy currents in applications such as transformers and inductors. "Soft" magnetic materials with low coercivity and hysteresis, such...
magnetic drag between the rotor and the hysteresis disk takes place causing rotation. In a sense, the hysteresis disk is pulled after the rotor. Depending...
engineers. He made ground-breaking discoveries in the understanding of hysteresis that enabled engineers to design better electromagnetic apparatus equipment...
field is applied (enough to achieve saturation). The effect of a magnetic hysteresis loop is measured using instruments such as a vibrating sample magnetometer;...
(Beisner et al. 2003). Hysteresis is an important concept in alternative stable state theory. In this ecological context, hysteresis refers to the existence...
static hydrophobicity, and contact angle hysteresis and slide angle are dynamic measures. Contact angle hysteresis is a phenomenon that characterizes surface...
both B and M also fall to zero (the material reaches the origin in the hysteresis curve). The distinction between the normal and intrinsic coercivity is...
increase. Core losses Hysteresis losses Each time the magnetic field is reversed, a small amount of energy is lost due to hysteresis within the core, caused...
treatment, as increasing the average crystal size decreases the hysteresis loss. Hysteresis loss is determined by a standard Epstein tester and, for common...
of magnetic hysteresis probably occurred before Ewing. However, Ewing re-discovered it, studied it in detail and coined the word hysteresis).[citation...
provide a clean digital output that is robust against sensor noise. The hysteresis thresholds for switching (specified as BOP and BRP) categorize digital...
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