first harmonic


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first harmonic

[¦fərst här′män·ik]
(physics)
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The parameters of the most used conductors in the form of steel trolley lines and aluminum tires for the first harmonic are given in Table 2.
This study, using noninvasive radial pulse waveform and harmonic analysis, further surveyed the predictive values of the first harmonic index for the heart disease, from the symptoms and signs of CAD and the left ventricular dysfunction to the ACE (myocardial infarction, heart failure, and cardiovascular death) in a prospective cohort study.
The amplitudes for the first harmonic are 173.42, 177.93, 127.77, and 188.78 mm for Debre Tabor, Bahir Dar, Gondar, and Dangila, respectively.
The literature proposes various acoustic parameters as possible cues to breathy voice, including high-frequency aspiration noise, low degree of periodicity, strong first harmonic, weak higher overtones, and steep spectral slope (Blankenship, The Time Course of Breathiness; Wayland and Jongman; Klatt and Klatt; Laver; Hillenbrand and Houde; Hillenbrand et al.; Keating and Esposito; Blankenship, "The Timing of Nonmodal").
The additional noise apparent in the sound measurements is either side banding due to insert runout, or in the case of the first harmonic, of the machine tool RPM probably some minor axis misalignment between the tool and spindle.
Although we allowed up to 12 harmonics for day of the year of conception based on a statistical step-up modeling procedure, we never needed to include more than the first harmonic (using p < 0.05 to assess the improvement in fit offered by the second harmonic, using likelihood ratio tests).
From the parametric model of the five-phase PMSM developed in Section II it was deduced that inter-turn faults may be diagnosed by analyzing the first harmonic of the ZSVC.
As was noted, one of major deficiencies of the reference band-pass filter was the first harmonic being close to the filter central frequency, and in the frequency response of this filter and in [2] the existence of this harmonic was not mentioned.
Then, in the simplest case, when low-pass filters passbands are equal to the fundamental frequency of the measured phase signal (i.e., low-pass filters passbands include the first harmonic of the measured phase signal and the input signal at the frequency of this harmonic could pass through low-pass filters without attenuation), signals (3) can be represented as
an integer larger than zero, [[omega].sub.f] is the fundamental frequency or the one corresponding to the first harmonic, t is a year from, and [[theta].sub.n] is the phase angle of the nth harmonic.
The encoder was calibrated using one reading head and the first harmonic was noticed in the chart.
The second method is to utilize a single resonator by properly controlling second mode or first harmonic [8-14].