Results 251 to 260 of about 189,622 (293)

Chaos in a Harmonically Excited Elastic Beam

Journal of Applied Mechanics, 1986
Numerical integration of the equations for the evolution of amplitudes of a harmonically forced simply supported elastic beam indicates that for certain values of the frequencies of excitation the response of the beam may be chaotically modulated. In an attempt to confirm the presence of chaos, the Lyapunov exponents have been calculated for two cases ...
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Self-Excitation and Harmonics in Wind Power Generation

Journal of Solar Energy Engineering, 2005
Traditional wind turbines are commonly equipped with induction generators because they are inexpensive, rugged, and require very little maintenance. Unfortunately, induction generators require reactive power from the grid to operate; capacitor compensation is often used.
Eduard Muljadi, Charles Butterfield, Harold Romanowitz, Robert Yinger   +3 more
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Second Harmonic Excitation Spectroscopy of Silver Nanoparticle Arrays

The Journal of Physical Chemistry B, 2005
Frequency-scanned excitation profiles of coherent second harmonic generation (SHG) were measured for silver nanoparticle arrays prepared by nanosphere lithography. The frequency of the fundamental beam did not coincide with the localized surface plasmon resonance (LSPR) of the nanoparticles and was tuned so that the coherent second harmonic (SH ...
Andrew M, Moran, Jiha, Sung, Erin M, Hicks, Richard P, Van Duyne, Kenneth G, Spears   +4 more
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A Harmonic Excitation System for Turbine Generators

Transactions of the American Institute of Electrical Engineers. Part III: Power Apparatus and Systems, 1962
A harmnonic excitation system, as the name implies, utilizes the harmonic power developed in a generator to selfexcite it. By means of a separate stator winding, this power is captured and controlled and rectified with a magnetic amplifier and silicon rectifiers. Protective features are included to prevent loss of excitation in the event of a rectifier
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Generation of Tollmien–Schlichting waves by harmonic excitation

Physics of Fluids, 1994
The creation of wavy disturbances (Tollmien–Schlichting waves) by a localized two-dimensional disturbance source vibrating periodically at a fixed frequency in a Blasius boundary layer is discussed. The initial-boundary value problem mathematically models the vibrating ribbon experiment of Schubauer and Skramstad. By considering the ribbon vibration to
Sengupta, T. K., Ballav, Manish, Nijhawan, Sandeep   +2 more
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Nonlinear Vibrations of a Beam Under Harmonic Excitation

Journal of Applied Mechanics, 1970
A straight beam with fixed ends, excited by the periodic motion of its supporting base in a direction normal to the beam span, was investigated analytically and experimentally. By using Galerkin’s method (one mode approximation) the governing partial differential equation reduces to the well-known Duffing equation.
Tseng, W. Y., Dugundji, John
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Harmonic Displacement Excitation at a Support

Journal of Mechanical Engineering Science, 1972
The various uses to which receptances may be put in linear vibration theory are well known. For some purposes it would be useful to have the direct receptance at a co-ordinate expressed in terms of parameters of that modified system which is defined when the co-ordinate concerned is locked.
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Sub-harmonic resonant solutions of a harmonically excited dry friction oscillator

Nonlinear Dynamics, 2006
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Csernák, G., Stépán, G., Shaw, S. W.
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Harmonic vector excitation coding of speech

Acoustical Science and Technology, 2006
A coding algorithm for speech called harmonic vector excitation coding (HVXC) has been developed that encodes speech at very low bit rates (2.0–4.0 kbit/s). It breaks speech signals down into two types of segments: voiced segments, for which a parametric representation of harmonic spectral magnitudes of LPC residual signals is used; and unvoiced ...
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Performance of Non-linear Vibration Isolators Under Harmonic Excitation

Journal of Sound and Vibration, 1994
Vibration isolators having non-linearity in both stiffness and damping terms are analyzed under harmonic excitations. Isolators with symmetric as well as asymmetric restoring forces are considered. The method of harmonic balance is used to obtain the steady state, harmonic response and transmissibility under both force and base excitations.
Ravindra, B., Mallik, A. K.
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