Search results for "SHIFT"
showing 10 items of 1226 documents
Technical and economical assessment of distributed electrochemical storages for load shifting applications: An Italian case study
2016
Time-of-use (TOU) energy cost management involves the use of energy storage systems (ESSs) by customers to reduce their electricity bills. The ESS is charged during off-peak time periods, when electricity energy prices are low, and discharged during times when on-peak energy prices are applied. This article addresses the question whether it is economically viable to install medium-scale distributed ESSs designed to lower the electricity cost for a customer-side application, assuming flexible electricity tariffs. The technical/economical evaluation is carried out referring to lithium-ion (Li-ion), sodium sulfur (NaS) and vanadium redox battery (VRB) technologies, performing a parametric anal…
Interaction between optical parabolic pulses in a Raman fiber amplifier
2009
We investigate the interaction between optical parabolic pulses in a Raman fiber amplifier. Self-similar amplification of two identical time-delayed pulses creates an oscillation which further evolves into a train of dark solitons through the combined effects of non-linearity, normal dispersion and adiabatic Raman gain. Theoretical predictions are in good agreement with experimental results.
Transmission performance ofN×160 Gbit s−1densely dispersion-managed optical fibre systems
2005
We carefully analyse the feasibility of N × 160 Gbit s−1 ultra-long haul transmissions in densely dispersion-managed (DDM) fibre systems. By using a novel analytical approach, we design highly optimized configurations of DDM fibre systems. Transmission performances of the analytically designed DDM fibre systems are evaluated using numerical simulations. We show that single-channel transoceanic transmissions at 160 Gbit s−1 may be achievable in DDM fibre systems, whereas multi-channel transmissions result in dramatically poor performances.
Acousto-optic interaction in biconical tapered fibers: shaping of the stopbands
2016
The effect of a gradual reduction of the fiber diameter on the acousto-optic (AO) interaction is reported. The experimental and theoretical study of the intermodal coupling induced by a flexural acoustic wave in a biconical tapered fiber shows that it is possible to shape the transmission spectrum, for example, substantially broadening the bandwidth of the resonant couplings. The geometry of the taper transitions can be regarded as an extra degree of freedom to design the AO devices. Optical bandwidths above 45 nm are reported in a tapered fiber with a gradual reduction of the fiber down to 70 μm diameter. The effect of including long taper transition is also reported in a double-tapered st…
Effect of wavelength dependence of nonlinearity, gain, and dispersion in photonic crystal fiber amplifiers
2005
Photonic crystal fibers are used in fiber amplifiers and lasers because of the flexibility in the design of mode area and dispersion. However, these quantities depend strongly on the wavelength. The wavelength dependence of gain, nonlinearity and dispersion are investigated here by including the wavelength dependence explicitly in the nonlinear Schr\"odinger equation for photonic crystal fibers with varying periods and hole sizes. The effect of the wavelength dependence of each parameter is studied separately as well as combined. The wavelength dependence of the parameters is shown to create asymmetry to the spectrum and chirp, but to have a moderating effect on pulse broadening. The effect…
A Computational Study on Temperature Variations in MRgFUS Treatments Using PRF Thermometry Techniques and Optical Probes
2021
Structural and metabolic imaging are fundamental for diagnosis, treatment and follow-up in oncology. Beyond the well-established diagnostic imaging applications, ultrasounds are currently emerging in the clinical practice as a noninvasive technology for therapy. Indeed, the sound waves can be used to increase the temperature inside the target solid tumors, leading to apoptosis or necrosis of neoplastic tissues. The Magnetic resonance-guided focused ultrasound surgery (MRgFUS) technology represents a valid application of this ultrasound property, mainly used in oncology and neurology. In this paper
phase-locked soliton pairs in a fiber ring laser
2002
We have experimentally observed the formation of stable pulse pairs with a π/2 phase difference in a passively mode-locked stretched-pulse fiber ring laser. We have developed a simplified theoretical model that, keeping the essential features of the experiment, reduces greatly the number of free parameters and solved it numerically. The agreement with the experimental results is excellent.
Silicon-microring into a fiber laser cavity for high-repetition-rate pulse train generation
2017
International audience; In 1997, Yoshida et al. inserted a Fabry-Perot filter in a modulation instability fiber laser cavity [1], the free spectral range (FSR) of the Fabry-Perot fixed the RF to 115 GHz; however the pulsed laser was poorly stable. Since then, lasers of increasing performance have been demonstrated using variants of this method. In 2012, Peccianti et al., demonstrated the first fiber laser harmonically mode-locked by integrated high-finesse microresonator [2]. The doped silica, on-chip microresonator provided both high spectral selectivity and nonlinearity, thus promoting the dynamics pulsed at 200 GHz. By using a silicon microring resonator (SMRR), this approach lead to the…
Parabolic pulse generation with dispersion decreasing optical fiber
2007
We experimentally demonstrate the possibility to generate parabolic pulses via a single dispersion decreasing optical fiber with normal dispersion. We numerically and experimentally outline the influence of the dispersion profile.
Passive compensation of the thermal drift of magnetostriction based Q-switched fiber lasers
2009
Abstract The authors propose and demonstrate a method to compensate the thermal drift of magnetostriction based Q-switched fiber lasers, which is caused by the eddy currents induced in the Terfenol-D magnetostrictive actuators. The consequent wavelength detuning between the fiber gratings of the laser is passively compensated by the use of Monel 400 as thermal actuator of the non-modulated grating. A highly stable pulsed signal is achieved in the range of 1 Hz–5 kHz, with a wavelength detuning between gratings maintained below 10 pm. Furthermore, an optimization of the use of the pump power is proposed, utilizing part of it for simultaneously pumping a fiber optic based amplification stage.