Search results for "nimi"

Efficiency Control for Permanent Magnet Synchronous Generators

2006

In this paper a control algorithm for the efficiency improvement of permanent magnet synchronous generators (PMSG) is presented. The proposed algorithm reduces the losses of the generator without affecting its performances. In details, after a description of a dynamic model of the PMSG, which has been purposely modified in order to take 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 PMSG employing the proposed algorithm are performed. The results of these simulations show that enhancement of the efficiency up to 3 % can be reached in comparison to a PMSG using a traditional con…

Minimization of detent force in a 1 kW linear permanent magnet generator for the conversion of sea waves energy: Numerical and experimental validation

2015

Linear permanent magnet generators are widely considered for the direct conversion of energy contained in sea waves [1-3]. Both planar and tubular structures have been proposed [4-6] and all these structures present several advantages: relative high efficiency, simplicity of the structures, high sturdiness. However, as all other linear machines they present some drawbacks: oscillations in the movement, distortion in the generated electromotive force (emf), etc. In this paper we focus our attention on the parasitic oscillations of the translator which are caused by the presence of a high detent force. Detent force is generated by the fact that magnetic energy presents a minimum when the leng…

MAGEMin 1.0.0

2022

MAGEMin is a Gibbs energy minimization solver package, which computes the thermodynamically most stable assemblage for a given bulk rock composition and pressure/temperature condition. It also returns parameters such as melt fraction or density, which can be combined with geodynamic/petrological tools to simulate, for example, the evolving chemistry of a crystallising melt. MAGEMin is written as a parallel C library and uses a combination of linear programming, extended Partitioning Gibbs free Energy and gradient-based local minimization to compute the most stable mineral assemblage. In this, it differs from exisisting approaches which makes it particularly suitable to utilize modern multic…

MAGEMin 1.0.0

2022

MAGEMin is a Gibbs energy minimization solver package, which computes the thermodynamically most stable assemblage for a given bulk rock composition and pressure/temperature condition. It also returns parameters such as melt fraction or density, which can be combined with geodynamic/petrological tools to simulate, for example, the evolving chemistry of a crystallising melt. MAGEMin is written as a parallel C library and uses a combination of linear programming, extended Partitioning Gibbs free Energy and gradient-based local minimization to compute the most stable mineral assemblage. In this, it differs from exisisting approaches which makes it particularly suitable to utilize modern multic…

Sondeo de l'Albufera de Pego (Valencia): micropaleontología y biofacies

1988

LA ANTIGUA ALBUFERA DE PEGO (VALENCIA-ESPAÑA) ES UN INTERESANTE PALEOSISTEMA DONDE LAS BIOFACIES REGISTRAN UNA HIDRODINAMICA SEDIMENTARIA DE ORIGEN MIXTO O PARALICO. EL GRADO DE INCIDENCIA Y ANTAGONISMO DE LAS AGUAS CONTINENTALES Y MARINAS QUEDA REGISTRADO EN FORAMINIFEROS, OSTRACODOS, MICROMOLUSCOS Y RESTOS VEGETALES, CUYA EVOLUCION CUANTITATIVA Y MORFOLOGICA, A TRAVES DEL SONDEO, REFLEJA NO SOLO EL GRADO DE EURIHALINIDAD DE LOS ORGANISMOS, SINO TAMBIEN LOS DIVERSOS EPISODIOS LITORALES DEL WURM II-III HASTA EL HOLOCENO, PASANDO POR LA TRANSGRESION FLANDRIENSE. (A)

Anotacions a la toponimia de La Ribera del Xúquer i encontorns

1978

Analyse toponymique de l’Horta de Valence (Espagne). Intégration des approches classique et critique pour la reconstruction et la valorisation de son…

2018

La comarca de l’Horta de València, la més poblada del País Valencià, rep aquest nom perquè fins a principis del segle XX la seua economia es basava en la seua riquíssima horta (‘terra de regadiu’). A partir de l’estudi dels topònims dels seus nuclis urbans (on l’horta ha estat eradicada) es reconstitueix virtualment el paisatge cultural hortícola perdut en les últimes dècades per a donar a conèixer a la ciutadania i així conscienciar-la del valor patrimonial d’aquest paisatge cultural de l’aigua desaparegut, i també per a revalorar el que sobreviu d’horta encara. Es porta a terme una anàlisi toponímica dels nuclis habitats de la comarca: d’una banda, seguint la metodologia clàssica de recol…

Raucherin vs. tupakkanainen : unidirektionale kontrastive Analyse femininer Personenbezeichnungen im Roman Unkenrufe / Kellosammakon huuto von Günte…

2006

Sustainable Approach to Waste-Minimized Sonogashira Cross-Coupling Reaction Based on Recoverable/Reusable Heterogeneous Catalytic/Base System and Ace…

2016

In this contribution, we present a chemically efficient and sustainable protocol for the palladium-catalyzed copper-free Sonogashira cross-coupling reaction, based on the use of a heterogeneous catalytic system. This consists in the combination of a palladium catalyst on highly cross-linked thiazolidine network on silica and a polystyrene-supported base. The solid catalyst/base system acts as a palladium scavenger avoiding leaching of the metal and consequent product contamination. The reaction can be conducted in safe and easily recoverable acetonitrile/water azeotrope as reaction medium. This proved to be an efficient greener alternative to the classic toxic aprotic media commonly used in…

Joint User Association and Dynamic Beam Operation for High Latitude Muti-beam LEO Satellites

2021

In Low Earth Orbit (LEO) satellites, which run in polar orbit, the area of overlap among beams becomes wider as the latitude of satellites increases, which leads to intolerable interference and extra energy consumption. To minimize the onboard power with QoS requirements, we propose an energy optimization model with considering power allocation, user association and dynamic beam ON/OFF operation jointly. Moreover, the frequent beam ON/OFF operations lead to the large number of user handovers, so handover cost is also considered in the model. The original problem is decomposed into two levels due to the high coupling of variables and the successive convex approximation is employed. A low com…