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Related to perturbation: Perturbation theory


Etymology: L, per + tubare, to disturb
a cause or a condition of disturbance, disorder, or confusion.


In physical therapy, an external force applied to a person's center of mass in an attempt to move it from the base of support


(pĕr″tĕr-bā′shŭn) [L. perturbare, thoroughly disordered]
1. The state of being greatly disturbed or agitated; uneasiness of mind.
2. A disturbance or a change in a structure or function, usually as a result of an external influence.


n a small disturbance that tips a metastable system over into disorder and chaos.
References in periodicals archive ?
In the following sections, we include a perturbation in the D5-brane configuration by simply adding lower and higher order symmetric polynomials in the [G.
In the first instance, a perturbation is triggered periodically for regular updating of the estimate and accounts for any relatively slow drift in the target parameters (quasi-static state).
The second category looks at the effects of perturbation training on the ability of older people to resist a simulated slip or trip in the laboratory (Grabiner et al.
For instance, signature "CPC020_PC3_24H:BRD-K94173926-001-01-6:10" contains a first part that identifies the experiment (CPC020), the cell line (PC3), and the perturbation time (24 h); the second part identifies the perturbation (BRD-K94173926), which in this case corresponds to the identifier of a small compound, followed by experimental information of location on the plate.
was defined as the rate of change of the scalar system perturbation (V = [partial derivative]X/[partial derivative]t) and was calculated as the slope of X with respect to time t.
3, during the current algorithm perturbation cycle/iteration, the power converter duty cycle and load current are denoted by D(k) and I (k), respectively.
In [5-13], RMPC problems for uncertain systems with time delays have been investigated, but the potential gain perturbation during the controller implementation stages has not been taken into consideration.
Keywords: Boundary Value Problems, Adomian Decomposition Method, Homotopy Perturbation Method.
The PV operating point is perturbed periodically by changing the voltage at PV source terminals, and after each perturbation the control algorithm compares the values of the power by the PV before and after the perturbation.
Such a choice for the form of perturbations is connected with possibility to present (by time coordinate t) every linearized perturbation as a Fourier series or a Fourier integral that is to get this perturbation as superposition of the elementary waves of the exponential type exp(-i[omega]t).
Using the nonlocal perturbation analysis techniques developed in [8, 9], nonlocal perturbation bounds are then derived.
Previous observations by WISE have also ruled out the Planet X-comet perturbation theory, Discovery News reported.