A study of using a single crystal photo-elastic modulator for active Q-switching of a fiber laser is presented. The modulator, which oscillates in a longitudinal eigenmode, was realized with LiTaO(3). This induces due to the photo-elastic effect a modulated artificial birefringence which modulates the polarization of passing light. When used together with a polarizer inside a laser cavity the l...

The Functional Electrical Stimulator design using monophasic spike-exponential waveform was proposed and described in this study. The monophasic square waveform has benefit in generating an action potential, but it could cause side effects such as toxic caused by the electrode polarization. The square waveform signal which the frequency and pulse width could be modulated was manipulated to be t...

This paper presents a novel three-phase utility frequency to high frequency soft switching power conversion circuit with dual mode pulse width modulation and pulse density modulation for high power induction heating applications as melting of steel and non ferrous metals, annealing of metals, surface hardening of steel and cast iron work pieces and hot water producers, steamers and super heated...

This paper describes a scheme to control the intrapulse energy variations of long pulse bursts of an induction linac. Analog control over the electron beam injector current is exercised in such a way that accelerator beam load variations compensate for thermal impedance variations of the accelerator cell ferrites. Circuit topology and test data are presented. The circuit uses 64 planar triodes ...

LLE Review, Volume 73 1 Pulsed-laser systems emit optical pulses having a temporal pulse shape characteristic of the particular type of laser design. Advances in technology have produced laser-pulseshaping systems where the laser temporal profile can be specified in advance and controlled to a high degree of accuracy.1–3 A pulse-shaping system has been in operation on OMEGA for several years. T...

Effects of pulse width on discrimination of simultaneous changes in frequency and level of electrical pulse trains were studied in a monkey subject with a cochlear implant. At test-stimulus levels where performance was minimum, frequency difference limens were larger for longer-duration pulses than that for shorter-duration pulses. Several factors may have contributed to these differences.

n this paper work, sensorless speed control of three phase induction motor is to be carried out using predictive current method and space vector PWM. A closed loop estimation system is proposed with robustness against motor parameters variation is used for the control approach. The novelty of the presented solution is the integration of a simple observer for both speed/flux and current control ...

The interaction between optical solitons and a forward Raman pump wave in fibers is investigated. It is found that when their relative velocity is small and the soliton pulse width is short, the soliton frequency is shifted by the interaction. Near zero relative velocity the pulse shape is distorted, in addition to having a frequency shift.

Abstract: As the size and the cost of power semiconductor switches are decreasing, converter topologies with high device count are starting to draw more attention. One such type of converters is the high frequency AC (hfac) link converters. A popular control method for these converters is Pulse Density Modulation (PDM). The hfac link voltage of the converter in this paper is a high frequency, t...

Digital Pulse–Width Modulation Control in Power Electronic Circuits: Theory and Applications