Search results for "OLT"
showing 10 items of 5524 documents
La produzione di sementi di frumento duro in Sicilia
2012
Caratteristiche e prospettive della produzione di sementi di frumento duro
2012
Grassland fire effect on soil organic carbon reservoirs in semiarid environment.
2011
The effect of fire on soil organic matter content is highly variable and depends on several factors including fire intensity, soil type and nature of burned material. Grassland in semiarid environment are often managed by shepherds with annual burning in order to enhance pasture recovery. The aim of this work was investigating the effect of fire as grassland management tool on soil organic carbon (SOC) reservoirs and on post-fire plant recovery. The study was conducted on Hyparrenia hirta grassland and Ampelodesma mauritanicus grassland, located in the Province of Palermo, in the north of Sicily. Soil samples were collected at two depth (0-5 and 5-20 cm) before and after experimental fire a…
Low toxicity metal halide semiconductors for optoelectronics and thermoelectrics
2023
Amb la finalitat de lluitar contra el canvi climàtic i donar suport a les energies renovables i no contaminants, l'objectiu principal d'aquesta tesi és la cerca i l'estudi de nous materials amb potencial aplicació en tres grans àrees d'investigació: la fotovoltaica, la termoelèctrica i els díodes emissors de llum (LED). Atés que molts dels materials emprats en aquestes àrees contenen components tòxics i nocius per al medi ambient, els materials desenvolupats en aquesta tesi a més presenten una baixa toxicitat i es poden preparar mitjançant mètodes de síntesis i deposició més sostenibles i ecològics. Concretament, es van utilitzar dos mètodes de síntesis: la mecanosíntesi en sec per molta de…
Il restauro del complesso di S. Michele Arcangelo a Palermo: i saggi archeologici
2000
Performance Improvement of Grid-Integrated Doubly Fed Induction Generator under Asymmetrical and Symmetrical Faults
2023
The doubly fed induction generator (DFIG)-based wind energy conversion system (WECS) suffers from voltage and frequency fluctuations due to the stochastic nature of wind speed as well as nonlinear loads. Moreover, the high penetration of wind energy into the power grid is a challenge for its smooth operation. Hence, symmetrical faults are most intense, inflicting the stator winding to low voltage, disturbing the low-voltage ride-through (LVRT) functionality of a DFIG. The vector control strategy with proportional–integral (PI) controllers was used to control rotor-side converter (RSC) and grid-side converter (GSC) parameters. During a symmetrical fault, however, a series grid-side converter…
Servant Leadership in a Nordic Healthcare Organization
2022
The aim of this chapter is to deepen the understanding of employees’ perceptions of servant leadership (SL) in the context of healthcare organizations. The empirical findings are based on the analysis of qualitative data collected in a Nordic healthcare organization that supports SL. Based on theory-driven content analysis, perceptions of SL were evaluated based on Spears’ definition of SL, which this chapter supports and develops. The findings show that SL seems to be a suitable approach for leadership in a healthcare organization. Its ethical and human-centered values especially seem to fit the context of healthcare. peerReviewed
I nodi della regolamentazione dei servizi pubblici locali
2017
Nel presente capitolo si sono selezionate tre problematiche, occorse in tre servizi locali distinti, allo scopo di evidenziare come anche nodi specifici di una singola disciplina regolatoria possano riverberarsi negativamente sul buon andamento complessivo dei servizi. Il primo paragrafo è dedicato all’esame delle modalità di espletamento delle gare e del regime di subentro tra gestori uscenti ed entranti nel settore della distribuzione del gas, con particolare riferimento alla disciplina del rimborso che i nuovi operatori sono tenuti a corrispondere alle precedenti gestioni per ripagarle degli investimenti compiuti e delle infrastrutture costruite. Il secondo si concentra su alcuni aspetti…
Shape identification in inverse medium scattering problems with a single far-field pattern
2016
Consider time-harmonic acoustic scattering from a bounded penetrable obstacle $D\subset {\mathbb R}^N$ embedded in a homogeneous background medium. The index of refraction characterizing the material inside $D$ is supposed to be Holder continuous near the corners. If $D\subset {\mathbb R}^2$ is a convex polygon, we prove that its shape and location can be uniquely determined by the far-field pattern incited by a single incident wave at a fixed frequency. In dimensions $N \geq 3$, the uniqueness applies to penetrable scatterers of rectangular type with additional assumptions on the smoothness of the contrast. Our arguments are motivated by recent studies on the absence of nonscattering waven…
A Model for the Study of Sheath Currents in Medium Voltage Cables for Industrial Application
2020
In this paper, the implementation of a simulation model for studying the effect of cross-bonding of metallic sheaths and/or non-magnetic armor of single-core medium voltage cables in the same circuit is discussed. With the use of single-core cables, the resistive losses due to the induced circulating currents in cable sheaths or armors causes an increase of cable temperature that reduces its ampacity. In addition, the risk of electric shock due to induced voltages may be present if a person is exposed to the armor/sheath at the unbounded end. For this reason, special bonding techniques are used to significantly reduce these currents. The authors have implemented a model that could be used t…