Search results for "Synchro"
showing 10 items of 886 documents
Luminescence and vacuum ultraviolet excitation spectroscopy of samarium doped SrB4O7
2020
Abstract Sm2+ and Sm3+ co-doped SrB4O7 could be utilized in several high-level optical devices and fundamental knowledge about the optical behavior of these materials benefits the development of luminescent applications. Herein, we report luminescence and its vacuum ultraviolet (VUV) excitation spectra in samarium doped SrB4O7. Both, Sm2+ and Sm3+ luminescence centers have been examined and distinguished in the emission and the excitation spectra investigated under synchrotron radiation. The contribution of either Sm2+ or Sm3+ emission lines into the emission spectra heavily depended on the excitation energy, and strong f-f transitions of both Sm2+ and Sm3+ were detected. At 10 K, a broad i…
Luminescence of γ-radiation-induced defects in α-quartz
2004
Optical transitions associated with γ-radiation-induced defects in crystalline α-quartz were investigated by photoluminescence excited by both pulsed synchrotron radiation and steady-state light. After a 10 MGy γ-dose we observed two emissions at 4.9 eV (ultraviolet band) and 2.7 eV (blue band) excitable in the range of the induced absorption band at 7.6 eV. These two luminescence bands show a different temperature dependence: the ultraviolet band becomes bright below 80 K; the blue band increases below 180 K, but drops down below 80 K. Both emissions decay in a timescale of a few ns under pulsed excitation, however the blue band could also be observed in slow recombination processes and it…
Efficiency Improvement of Inverter-Fed Permanent Magnet Synchronous Motors
2003
In this paper a control algorithm for the efficiency improvement of inverter-fed permanent magnet synchronous motors (PMSMs) is presented. The proposed algorithm allows reducing the losses of the drive without reduction of its dynamic performances. In details, after recalling a dynamic model of the PMSM, which has been purposely modified and that takes into account the iron losses, the basic equations and the constraints to obtain the loss minimization are presented and discussed. Some simulations of a specific PMSM drive employing the proposed algorithm are performed. The results of these simulations show that the dynamic performances are maintained, and enhancement of the efficiency up to…
Assessment of energy management technique for achieving the sustainable voltage level during grid outage of hydro generator interfaced DC Micro-Grid
2021
Abstract An appropriate energy management scheme is needed for the reliable and sustainable operation of DC microgrid. The energy management scheme of DC microgrid (MG) is mainly controlled by main energy resource of MG. Main energy resource needs to be dispatchable unit for forming the reference voltage within DC MG. In this work, a micro hydro generator (MHG) is considered as a dispatchable source for forming the sustainable voltage level of DC MG operating under the abnormal condition. In this work, the abnormality refers to the outage of solar PV due to intermittency during fluctuating load condition. But, due to mechanical time constant of MHG and rate of charging/discharging current l…
A Constrained Optimal Model Predictive Control for Mono Inverter Dual Parallel PMSM Drives
2018
The actual trends in the design of AC drives are directed to the reduction of the total weight, volume and cost. Usually, this implies the necessity to adopt new motor topologies and converter architectures. An important role is played by the mono-inverter dual parallel motor (MIDP), which gives the possibility to reduce the total weight and costs of power converters. This paper proposes a novel model predictive control algorithm in order to improve the transient performances of a MIDP used for an overhead carrier. The effectiveness of the proposal control is verified through some numerical simulations.
Nest aggregation and reproductive synchrony promote Lesser Kestrel Falco naumanni seasonal fitness
2013
Several factors promote coloniality by enhancing the fitness of colony members. In birds, spatial proximity among nests, breeder abundance and reproductive synchrony have been proposed as primary factors responsible for enhanced colonial defence and foraging success, which, in turn, enhance reproductive success. Whether these factors function synergistically or antagonistically remains, however, an open question due to the absence of an integrated analysis of their effects on fitness. We studied a large population of the Lesser Kestrel, Falco naumanni, a facultative colonial species, breeding in colonies of different sizes in their typical pseudo-steppe habitat. We quantified both the singu…
Nuclear Resonance Scattering Using Synchrotron Radiation (Mössbauer Spectroscopy in the Time Domain)
2010
Conventional Mossbauer spectroscopy (MS) can be considered as “spectroscopy in the energy domain.” It has been widely used since its discovery in 1958 [1]. Nuclear resonant forward scattering (NFS) of synchrotron radiation has been successfully employed as a time-differential technique since 1991 [2]. Another related technique, nuclear inelastic scattering (NIS) of synchrotron radiation [3], can be regarded as an extension of conventional, energy-resolved MS (in the range 10−9 to 10−7 eV) to energies on the order of molecular vibrations (in the range 10−3 to 10−1 eV). So far only a few “Mossbauer” stations for NFS and NIS measurements have become available in synchrotron laboratories, i.e.,…
Resonant X-Ray Scattering of Biological Systems
1987
Nearly all synchrotron radiation laboratories at high energy electron storage rings put enormous effort into the developement of resonant (anomalous) X-ray scattering techniques. So does the Hamburger Synchrotronstrahlungslabor (HASYLAB) at Hamburg. One of these intruments which is built in cooperation with the university of Mainz at the beam line A1 of the storage ring DORIS. How does the physics of resonant scattering enter into the design of the X-ray instrument.
Effects of reversible lane implementation, a case study simulation
2019
In a modern society, transport is a necessity for carrying out certain activities that human communities are involved in. This need for mobility is on a continuous rise and can be characterized by the possibility of moving from one point to another, using different means of transport, in order to facilitate the performed activities. The purpose of this research is to design and evaluate the implementation of a system of reversible lanes using simulation. As methodology, it starts from an analysis of data collected from real traffic condition through implementation and simulation with the Synchro application. The analysis proposes solutions to decongest traffic through the implementation of …
Low-cost motion control solution for industrial manufacturing systems
2011
This paperwork deals with a low-cost actuation solution, based upon induction motors, which was seldom used in the motion control systems, especially for the machine tools feed drives. A simulation approach, based upon a mathematical model of the induction motor, for tuning the controllers of the systems is presented. Experimental researches developed upon a two axes motion control system, both axes being driven by alternating current asynchronous motors were also performed in order to test the proposed strategies. The asynchronous motors, used as actuation devices were equipped with incremental rotary encoders and controlled by vector frequency inverters and DSP motion control cards were u…