The effect of group-delay ripples in dispersion-managed soliton communication systems that use chirped fiber gratings for dispersion compensation is studied. Using both a reduced model and direct numerical simulation, we find that dispersion-managed solitons exist even in the presence of large dispersion variation caused by group-delay ripples. The dispersion-managed solitons suppress the growt...

This paper has described the application of the newly developed direct torque control (DTC) scheme for the reduction of common mode voltage of an induction motor drive. This DTC scheme for the reduction of common mode voltage does not use any zero voltage vectors. To validate the proposed algorithm, numerical simulation has been carried out using MATLAB-Simulink and results are presented and co...

Interictal fast oscillations between 100 and 500 Hz have been reported in signals recorded from implanted microelectrodes in epileptic patients and experimental rat models. Oscillations between 250 and 500 Hz, or fast ripples (FR), appeared related to the epileptic focus whereas ripples (80-200 Hz) were not. We report high-frequency oscillations recorded with intracranial macroelectrodes in sev...

BACKGROUND Hippocampal sharp-wave ripples (SWRs) arising from synchronous bursting in CA3 pyramidal cells and propagating to CA1 are thought to facilitate memory consolidation. Stimulation of the CA3 axon collaterals comprising the hippocampal commissure in rats interrupts sharp-wave ripples and leads to memory impairment. In primates, however, these commissural collaterals are limited. Other h...

This paper presents an original study on the generated torque ripples of phase commutation in the Four-Switch, Three-Phase Inverter (FSTPI) Brushless DC (BLDC) motor drive which is suitable for low cost applications. Analytic values of torque ripple and commutation duration are obtained for different operation conditions. Moreover, limitation on the speed range operation caused from splitti...

High-frequency (100-500 Hz) oscillations (HFOs) recorded from intracranial electrodes are a potential biomarker for epileptogenic brain. HFOs are commonly categorized as ripples (100-250 Hz) or fast ripples (250-500 Hz), and a third class of mixed frequency events has also been identified. We hypothesize that temporal changes in HFOs may identify periods of increased the likelihood of seizure o...

Using new large-scale wave-flume experiments we examine the cross-section and planform geometry of wave-formed ripples in coarse sand (median grain sizeD50 = 430 μm) under high-energy shoaling and plunging random waves. We find that the ripples remain orbital for the full range of encountered conditions, even for wave forcing when in finer sand the ripple length λr is known to become independen...

A large data set on ripples was collected and examined. A set of new formulas for the prediction of the ripple characteristics is proposed with an emphasis on the disappearance of the ripples. The ripple wavelength was observed to be proportional to the bottom wave excursion but also to be a function of the grain-related Shields parameter and wave period parameter introduced by Mogridge et al. ...