Search results for "SCAD"

Real-Time Power Flow Monitoring and Control System for Microgrids Integration in Islanded Scenarios

2019

This article presents an enhanced system for real-time power flow monitoring and control (PFMC) for microgrids integration in medium-voltage (MV) distribution networks. The developed solution includes both system architecture and the monitoring and control algorithms, and it has low implementation and installation costs. It is based on the use of hardware and software solutions previously proposed by the authors, i.e., a distributed measurement, a control and communication architecture, and a supervisory control and data acquisition (SCADA) software, which have been enhanced and integrated for the considered application. The SCADA implements a load flow (LF) algorithm for real-time power fl…

Mechanism of self-trapped hole motion in corundum crystals

1993

Abstract Atomistic simulations of the self-trapped hole eauilibrium geometry and migration in a pure corundum crystal have been carried out using the semiempirical method of intermedia te neglect of differential overlap and atom-atom potentials, as implemented in the CASCADE code. The activation energies for three different hole-hopping mechanisms are calculated. It is shown that the 60° reorientations of a self-trapped hole and hopping to the nearest O-atom triangle reauire almost the same activation energy, approximately 0.9 eV, which agrees auite well with the experi-mental value for hole migration of 0.7 eV. A new mechanism of small-polaron motion is suggested.

Italian marine reserve effectiveness: does enforcement matter?

2008

Marine protected areas (MPAs) have become popular tools worldwide for ecosystem conservation and fishery management. Fish assemblages can benefit from protection provided by MPAs, especially those that include fully no-take reserves. Fish response to protection can thus be used to evaluate the effectiveness of marine reserves. Most target fish are high-level predators and their overfishing may affect entire communities through trophic cascades. In the Mediterranean rocky sublittoral, marine reserves may allow fish predators of sea urchins to recover and thus whole communities to be restored from coralline barrens to macroalgae. Such direct and indirect reserve effects, however, are likely t…

Modified Modulation Techniques for Quasi-Z-Source Cascaded H-Bridge Inverters

2018

Quasi-Z-source cascaded H-bridge (q Z S - C H B) inverters are one promising solution for high power photovoltaic (PV) systems. This type of topologies inherits the advantages of cascaded converters (i.e., multilevel outputs) and impedance-source inverters (i.e., high conversion ratios). In addition, it allows increasing the inverter reliability (with high redundancy). However, the modulation and control of qZS-CHB inverters are challenging to a certain extent. Thus, this paper proposes modified modulation techniques to increase the performances of qZS-CHB converters in terms of voltage gains and stresses. The novelty lies in the use of the switching frequency optimal as reference signals i…

Gaig blau, Carraca (VER0000055)

Altres noms vulgars: European Roller (Anglès), Rollier d'Europe (Francès), Blauracke (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 31-3 Adulto Adulto garrulus _

Characteristics of the diffuse astrophysical electron and Tau neutrino flux with six years of IceCube high energy cascade data

2020

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of φastro=1.66-0.27+0.25 at E0=100 TeV, in agreement with IceCube's complementary muon neutrino results and wit…

Geografía: espacio social e imágenes de marca : el análisis de "Flor de mayo" de Vicente Blasco Ibáñez

1988

A TRAVES DE UN ANALISIS MINUCIOSO DE LA OBRA DEL NOVELISTA VALENCIANO VICENTE BLASCO IBAÑEZ (1867-1928), "FLOR DE MAYO", PODEMOS RECONSTRUIR EL ESPACIO VIVIDO DE LOS HABITANTES DEL CABANYAL DE PRINCIPIOS DE SIGLO. LA ACCION DE LA NOVELA, QUE FUE ESCRITA EN 1895, RECOGE LAS FORMAS DE VIDA DE LOS MARINEROS Y PESCADORES VALENCIANOS, EN SUS DIFERENTES ESPACIOS OPERATIVOS: EL ESPACIO DE LA PESCA, EL ESPACIO DEL CONTRABANDO, EL PROPIO PUEBLO DEL CABANYAL, LA CIUDAD DE VALENCIA, ARGEL, AFRICA, EL MEDITERRANEO. BLASCO IBAÑEZ RECOGIO CON VERACIDAD LOS ESPACIOS DE ACCION DE SUS PERSONAJES Y, GRACIAS A SU POPULARIDAD, HA CONTRIBUIDO A CREAR Y RECREAR ENTRE SUS LECTORES, LAS "IMAGENES DE MARCA" DE LUGA…

Model predictive control for continuous lactide ring‐opening polymerization processes

2020

International audience; Polylactic acid (PLA) is an attractive environment-friendly thermoplastic that is bio-sourced and biodegradable. PLA is industrially produced by the ring-opening polymerization of Lactide. This reaction is sensitive to drifts in the operating conditions and impurities in the raw materials that may affect the reaction rate as well as the polymer properties, which can be very costly in continuous processes. It is therefore crucial to employ a control strategy that allows recovering the nominal conditions and maintaining the desired properties and conversion level in case of drift. Three control strategies are discussed in this paper: Proportional-Integral controller (P…

Structure analysis on the nanoscale: closed WS2 nanoboxes through a cascade of topo- and epitactic processes

2014

Closed WS2 nanoboxes were formed by topotactic sulfidization of a WO3/WO3·⅓H2O intergrowth precursor. Automated diffraction tomography was used to elucidate the growth mechanism of these unconventional hollow structures. By partial conversion and structural analysis of the products, each of them representing a snapshot of the reaction at a given point in time, the overall reaction can be broken down into a cascade of individual steps and each of them identified with a basic mechanism. During the initial step of sulfidization WO3·⅓H2O transforms into hexagonal WO3 whose surface allows for the epitaxial induction of WS2. The initially formed platelets of WS2 exhibit a preferred orientation wi…

The domino reaction between 4,6-dinitrobenzofuroxan and cyclopentadiene. Insights on the nature of the molecular mechanism

2004

Abstract The molecular mechanism of the domino reaction between 4,6-dinitrobenzofuroxan, 1 , and cyclopentadiene, Cp, to give the adduct 11 is examined through density functional theory (DFT) calculations at B3LYP/6-31G* level. This domino reaction comprises two consecutive formally [4+2] cycloadditions. The first one is a two-center addition initialized by the nucleophilic attack of Cp to the more electrophilic center of 1 . The subsequent cyclization can take place along two competitive channels associated to the formation of a second C–C bond yielding the formally [2+4] cycloadduct 9 , or a C–O bond yielding the formally [4+2] cycloadduct 10 . The second cycloaddition is a stepwise proce…