v.

(周期的に)変動する、振動する、発振する

関: fluctuate、fluctuation、oscillation、oscillatory、shake、variance、variation、vary、vibrate、vibration

WordNet

move or swing from side to side regularly; "the needle on the meter was oscillating" (同)vibrate
the quality of being unsteady and subject to changes; "he kept a record of price fluctuations" (同)wavering
a wave motion; "the fluctuations of the sea"
shake (a body part) to communicate a greeting, feeling, or cognitive state; "shake ones head"; "She shook her finger at the naughty students"; "The old enemies shook hands"; "Dont shake your fist at me!"
move with or as if with a tremor; "his hands shook" (同)didder
undermine or cause to waver; "my faith has been shaken"; "The bad news shook her hopes"
move or cause to move back and forth; "The chemist shook the flask vigorously"; "My hands were shaking" (同)agitate
get rid of; "I couldnt shake the car that was following me" (同)shake_off, throw off, escape from
bring to a specified condition by or as if by shaking; "He was shaken from his dreams"; "shake the salt out of the salt shaker"
(astronomy) any perturbation of the mean motion or orbit of a planet or satellite (especially a perturbation of the earths moon)
the process of varying or being varied
an activity that varies from a norm or standard; "any variation in his routine was immediately reported" (同)variance
an artifact that deviates from a norm or standard; "he patented a variation on the sandal"
the act of changing or altering something slightly but noticeably from the norm or standard; "who is responsible for these variations in taxation?"
an instance of change; the rate or magnitude of change (同)fluctuation
a repetition of a musical theme in which it is modified or embellished
be subject to change in accordance with a variable; "Prices vary"; "His moods vary depending on the weather"
make something more diverse and varied; "Vary the menu" (同)variegate, motley
cause to fluctuate or move in a wavelike pattern
be unstable; "The stock market fluctuates"
move or sway in a rising and falling or wavelike pattern; "the line on the monitor vacillated" (同)vacillate, waver
an official dispensation to act contrary to a rule or regulation (typically a building regulation); "a zoning variance"
the second moment around the mean; the expected value of the square of the deviations of a random variable from its mean value

PrepTutorEJDIC

振り子運動をする,(2点間を振り子のように)振動する,揺れる《+『between』+『名』》 / (…の間を)〈意見・信念などが〉動揺する,ぐらつく《+『between』+『名』》
波動;動揺,変動
(前後・上下・左右などに)…‘を'『振る,』揺り動かす,揺する / (…から)…‘を'『振り落とす』《+『名』+『from』(『out of』)+『名』》 / 〈地震・爆発などが〉…‘を'『震動される』 / 〈基礎・信念など〉‘を'『動揺させる,』ぐらつかせる / 〈人〉‘を'動揺させる,』‘を'心をかき乱す / 〈ちり・病気・悪習・追っ手など〉‘を'振り払う,振り切る,除く《+『off』+『名,』+『名』+『off』》 / 『揺れる,』震動する / (恐布・寒さなどで)『振える』《+『with』+『名』》 / 揺り動かす / 〈C〉『揺ること』;揺れ;震え / 《the shakes》《話》(熱・寒けによる)身震い,悪寒(おかん)
{U}『変化(変動)すること』 / {C}(個々の)変化;変化の量(程度) / {C}変形,変わり種;(生物の)変種 / {C}(…の)変奏曲《+on+名》
(…から…に)『変わる』,変化する《+from+名+to+名》 / (…の点で)『互いに異なる』,いろいろである《+in(on)+名》 / …‘を'『変える』,変更する / …‘に'変化をつける,‘を'変化に富ませる
動揺する,変動する,上下する
変化,多様性;相違,不一致

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/09/19 13:43:31」(JST)

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[Wiki en表示]

An undamped spring–mass system is an oscillatory system

Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. The term vibration is precisely used to describe mechanical oscillation. Familiar examples of oscillation include a swinging pendulum and alternating current power.

Oscillations occur not only in mechanical systems but also in dynamic systems in virtually every area of science: for example the beating human heart, business cycles in economics, predator–prey population cycles in ecology, geothermal geysers in geology, vibrating strings in musical instruments, periodic firing of nerve cells in the brain, and the periodic swelling of Cepheid variable stars in astronomy.

1 Simple harmonic oscillator
2 Damped and driven oscillations
3 Coupled oscillations
4 Continuous systems – waves
5 Mathematics
6 Examples
- 6.1 Mechanical
- 6.2 Electrical
- 6.3 Electro-mechanical
- 6.4 Optical
- 6.5 Biological
- 6.6 Human
- 6.7 Economic and social
- 6.8 Climate and geophysics
- 6.9 Astrophysics
- 6.10 Quantum mechanical
- 6.11 Chemical
7 See also
8 References
9 External links

Simple harmonic oscillator

The simplest mechanical oscillating system is a weight attached to a linear spring subject to only weight and tension. Such a system may be approximated on an air table or ice surface. The system is in an equilibrium state when the spring is static. If the system is displaced from the equilibrium, there is a net restoring force on the mass, tending to bring it back to equilibrium. However, in moving the mass back to the equilibrium position, it has acquired momentum which keeps it moving beyond that position, establishing a new restoring force in the opposite sense. If a constant force such as gravity is added to the system, the point of equilibrium is shifted. The time taken for an oscillation to occur is often referred to as the oscillatory period.

Systems where the restoring force on a body is directly proportional to its displacement, such as the dynamics of the spring-mass system, are described mathematically by the simple harmonic oscillator and the regular periodic motion is known as simple harmonic motion. In the spring-mass system, oscillations occur because, at the static equilibrium displacement, the mass has kinetic energy which is converted into potential energy stored in the spring at the extremes of its path. The spring-mass system illustrates some common features of oscillation, namely the existence of an equilibrium and the presence of a restoring force which grows stronger the further the system deviates from equilibrium.

Damped and driven oscillations

All real-world oscillator systems are thermodynamically irreversible. This means there are dissipative processes such as friction or electrical resistance which continually convert some of the energy stored in the oscillator into heat in the environment. This is called damping. Thus, oscillations tend to decay with time unless there is some net source of energy into the system. The simplest description of this decay process can be illustrated by oscillation decay of the harmonic oscillator.

In addition, an oscillating system may be subject to some external force, as when an AC circuit is connected to an outside power source. In this case the oscillation is said to be driven.

Some systems can be excited by energy transfer from the environment. This transfer typically occurs where systems are embedded in some fluid flow. For example, the phenomenon of flutter in aerodynamics occurs when an arbitrarily small displacement of an aircraft wing (from its equilibrium) results in an increase in the angle of attack of the wing on the air flow and a consequential increase in lift coefficient, leading to a still greater displacement. At sufficiently large displacements, the stiffness of the wing dominates to provide the restoring force that enables an oscillation.

Coupled oscillations

Two pendulums with the same period fixed on a string act as pair of coupled oscillators. The oscillation alternates between the two.

Experimental Setup of Huygens synchronization of two clocks

The harmonic oscillator and the systems it models have a single degree of freedom. More complicated systems have more degrees of freedom, for example two masses and three springs (each mass being attached to fixed points and to each other). In such cases, the behavior of each variable influences that of the others. This leads to a coupling of the oscillations of the individual degrees of freedom. For example, two pendulum clocks (of identical frequency) mounted on a common wall will tend to synchronise. This phenomenon was first observed by Christiaan Huygens in 1665.^[1] The apparent motions of the compound oscillations typically appears very complicated but a more economic, computationally simpler and conceptually deeper description is given by resolving the motion into normal modes.

More special cases are the coupled oscillators where energy alternates between two forms of oscillation. Well-known is the Wilberforce pendulum, where the oscillation alternates between an elongation of a vertical spring and the rotation of an object at the end of that spring.

Continuous systems – waves

As the number of degrees of freedom becomes arbitrarily large, a system approaches continuity; examples include a string or the surface of a body of water. Such systems have (in the classical limit) an infinite number of normal modes and their oscillations occur in the form of waves that can characteristically propagate.

Mathematics

Oscillation of a sequence (shown in blue) is the difference between the limit superior and limit inferior of the sequence.

The mathematics of oscillation deals with the quantification of the amount that a sequence or function tends to move between extremes. There are several related notions: oscillation of a sequence of real numbers, oscillation of a real valued function at a point, and oscillation of a function on an interval (or open set).

Examples

Mechanical

Double pendulum
Foucault pendulum
Helmholtz resonator
Oscillations in the Sun (helioseismology), stars (asteroseismology) and Neutron-star oscillations.
Quantum harmonic oscillator
Playground swing
String instruments
Torsional vibration
Tuning fork
Vibrating string
Wilberforce pendulum
Lever escapement

Electrical

Alternating current
Armstrong (or Tickler or Meissner) oscillator
Astable multivibrator
Blocking oscillator
Butler oscillator
Clapp oscillator
Colpitts oscillator
Delay line oscillator
Dow (or ultra-audion) oscillator
Electronic oscillator
Extended interaction oscillator
Hartley oscillator
Oscillistor
Phase-shift oscillator
Pierce oscillator
Relaxation oscillator
RLC circuit
Royer oscillator
Vačkář oscillator
Wien bridge oscillator

Electro-mechanical

Crystal oscillator

Optical

Laser (oscillation of electromagnetic field with frequency of order 10¹⁵ Hz)
Oscillator Toda or self-pulsation (pulsation of output power of laser at frequencies 10⁴ Hz – 10⁶ Hz in the transient regime)
Quantum oscillator may refer to an optical local oscillator, as well as to a usual model in quantum optics.

Biological

Circadian rhythm
Circadian oscillator
Lotka–Volterra equation
Neural oscillation
Oscillating gene
Segmentation oscillator

Human

Neural oscillation
Insulin release oscillations
gonadotropin releasing hormone pulsations
Pilot-induced oscillation
Voice production

Economic and social

Business cycle
Generation gap
Malthusian economics
News cycle

Climate and geophysics

Atlantic multidecadal oscillation
Chandler wobble
Climate oscillation
El Niño-Southern Oscillation
Pacific decadal oscillation
Quasi-biennial oscillation

Astrophysics

Neutron stars
Cyclic Model

Quantum mechanical

Neutrino oscillations
Quantum harmonic oscillator

Chemical

Belousov–Zhabotinsky reaction
Mercury beating heart
Briggs–Rauscher reaction
Bray–Liebhafsky reaction

References

^ Strogatz, Steven. Sync: The Emerging Science of Spontaneous Order. Hyperion, 2003, pp 106-109

External links

Vibrations – a chapter from an online textbook

UpToDate Contents

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English Journal

Label-free and high-sensitive detection of human breast cancer cells by aptamer-based leaky surface acoustic wave biosensor array.

Chang K1, Pi Y2, Lu W1, Wang F1, Pan F1, Li F1, Jia S1, Shi J3, Deng S4, Chen M5.
Biosensors & bioelectronics.Biosens Bioelectron.2014 Oct 15;60:318-24. doi: 10.1016/j.bios.2014.04.027. Epub 2014 Apr 30.
A label-free and high-sensitive sensing technology for tumor cell recognition and detection was developed based on a novel 2 × 3 model of leaky surface acoustic wave (LSAW) aptasensor array. In this methodology, every resonator crystal unit of the LSAW aptasensor array had an individual oscillator
PMID 24836014

Fragility in dynamic networks: application to neural networks in the epileptic cortex.

Sritharan D1, Sarma SV.
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Epilepsy is a network phenomenon characterized by atypical activity at the neuronal and population levels during seizures, including tonic spiking, increased heterogeneity in spiking rates, and synchronization. The etiology of epilepsy is unclear, but a common theme among proposed mechanisms is that
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Droplet manipulation in a microfluidic chamber with acoustic radiation pressure and acoustic streaming.

Cheung YN1, Nguyen NT, Wong TN.
Soft matter.Soft Matter.2014 Sep 4. [Epub ahead of print]
The present paper reports a novel manipulation method for droplets using acoustic radiation pressure and acoustic streaming. In an acoustic field, droplets deform, oscillate and move in a wide range of applied frequencies. The behavior of a droplet depends on the droplet size, acoustic field and int
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The Parietal Reach Region Selectively Anti-Synchronizes with Dorsal Premotor Cortex during Planning.

Stetson C1, Andersen RA2.
The Journal of neuroscience : the official journal of the Society for Neuroscience.J Neurosci.2014 Sep 3;34(36):11948-58. doi: 10.1523/JNEUROSCI.0097-14.2014.
Recent reports have indicated that oscillations shared across distant cortical regions can enhance their connectivity, but do coherent oscillations ever diminish connectivity We investigated oscillatory activity in two distinct reach-related regions in the awake behaving monkey (Macaca mulatta): th
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