Results 161 to 170 of about 1,050 (195)

Subharmonic mechanism of the mode C instability

Physics of Fluids, 2005
The perturbation field of the recently discovered subharmonic mode C instability in the wake behind a ring is compared via a side-by-side comparison to the perturbation fields of the modes A and B instabilities familiar from past studies of the vortex street behind a circular cylinder.
Sheard, G. J., Thompson, M. C., Hourigan, K.   +2 more
openaire   +1 more source

On the generation of sets of subharmonic modes in a piecewbe-continuous system

Prikladnaya Matematika I Mekhanika, 1974
exaly   +3 more sources

Comparison of subharmonic synchronous mode-locking with subharmonic hybrid mode-locking of a monolithic DBR laser operating at millimeter wave frequencies

International Topical Meeting on Microwave Photonics. MWP '96 Technical Digest. Satellite Workshop (Cat. No.96TH8153), 2002
A detailed comparison of subharmonic synchronous mode-locking and subharmonic hybrid mode-locking of a monolithic DBR laser is presented. While subharmonic electrical injection offers ease of implementation, subharmonic optical injection offers advantages of reduced amplitude modulation and larger locking ranges.
A. Nirmalathas, H.F. Liu, D. Novak, Z. Ahmed, Y. Ogawa   +4 more
openaire   +1 more source

Subharmonics and chaos in a controlled switched-mode power converter

IEEE Transactions on Circuits and Systems, 1988
A difference equation is derived for the output current, at successive switch events, of a simple switching-regulator DC/DC converter using a pulsewidth modulator. Wideband feedback control of the nonlinear circuit leads to a one-dimensional return map of zigzag form from which a stability criterion is found.
D.C. Hamill, D.J. Jeffries
openaire   +1 more source

Subharmonic hybrid mode-locking of a monolithic semiconductor laser

IEEE Journal of Selected Topics in Quantum Electronics, 1996
Performance of a subharmonically hybrid mode-locked (SH-ML) monolithic semiconductor laser is investigated. A 33-GHz passively mode-locked distributed Bragg reflector semiconductor laser is stabilized by the injection of an electrical signal with a subharmonic frequency of the laser cavity resonance.
T. Hoshida, null Hai-Feng Liu, M. Tsuchiya, Y. Ogawa, T. Kamiya   +4 more
openaire   +1 more source

On the stability and subharmonic susceptibility of current-mode controlled converters

PESC `92 Record. 23rd Annual IEEE Power Electronics Specialists Conference, 2003
The authors present stability conditions for constant switching frequency power converters with current-mode control. The conditions take fully into account the interaction of the current and voltage feedback loops, and give explicit limits for the loop gains as a function of the duty ratio and the slope of the compensation ramp.
A.V. Anunciada, M.M. Silva
openaire   +1 more source

Subharmonic anti-phase dynamics in coupled mode-locked semiconductor lasers

Optics Letters, 2017
We show that coupled mode-locked semiconductor lasers can operate in a subharmonic regime in which the two lasers pulsate in an anti-phase manner at one-half the fundamental mode-locking frequency of the solitary lasers. In the subharmonic mode, each pulse has almost twice the energy carried by the isolated lasers in the fundamental mode-locked regime ...
Sudarshan, Sivaramakrishnan, Herbert G, Winful   +1 more
openaire   +2 more sources

Subharmonic Response of Polymer Contrast Agents Based on the Empirical Mode Decomposition

IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2016
The subharmonic threshold for ultrasound contrast agents has been defined as a 20-25 dB difference between the fundamental and subharmonic (2/1) spectral components of the backscatter signal. However, this Fourier-based criterion assumes a linear time-invariant signal.
Rintaro Hayashi, John S. Allen, Parag V. Chitnis, Jonathan Mamou, Jeffrey A. Ketterling   +4 more
openaire   +2 more sources

Subharmonic and Superharmonic Resonances in the Pitch and Roll Modes of Ship Motions

Journal of Hydronautics, 1974
We considered the motion of a ship with two degrees of freedom—pitch and roll—when secondorder, static couplings are included in the equations of motion, and we obtained a nonlinear analysis of the response of the ship to a harmonic excitation (i.e., a regular sea) using the method of multiple scales.
Dean T. Mook, Larry R. Marshall, Ali H. Nayfeh   +2 more
openaire   +1 more source

Intermittent chaos and subharmonics in current-mode controlled SEPIC converters

2008 3rd IEEE Conference on Industrial Electronics and Applications, 2008
Intermittent phenomena are commonly observed in periodically driven switching power converters. This paper explores the intermittent chaos and subharmonics in a current-mode controlled SEPIC converter using a circuit model with intruding interference. The theoretical analysis and computer simulation are prensted, which indicate that the signal strength
null Xue-dong Jiang, null Yu-fei Zhou, null Jun-ning Chen, null Shi-bing Wang   +3 more
openaire   +1 more source