3,141 research outputs found
Approaches to shipboard power generation systems design and management. Probabilistic approach to load prediction and system optimal design, sizing and management
No full textThis doctoral thesis presents new ideas and formulations on shipboard power system sizing and management. The main motivation behind this work is to fill, at least in part, the current technological and mythological gap between land and marine applications, concerning the sizing and management of power systems. This gap is the result of several changes regarding both the electric and marine applications. Two of these are, for example, the recent increase of electric power installed on board modern vessels and recent development of technologies for land microgrids. In this context, it should be noted that, also the modern ships are comparable to land microgrids, where the generation and loads are close in space and the on board power system may work either islanded or connected to the land grid. Nowadays, microgrids are a hot topic in electric engineering, with a constant development of novel approaches for both their sizing and management. On the other hand, considering the increase in the power installed on board ships, the traditional methods developed in the last century to size and manage these systems have shown increasing limitations and inaccuracies. This results in oversized power generation systems, low performances and high level of air and sea pollution due to ships activities. To overcome these problems and criticalities, this work presents a probabilistic approach to load prediction, which may increase the flexibility of the power system design and allow a significant reduction in the total power installed. Moreover, the traditional method to size the diesel generators, based on satisfying the maximum load, it is revised with the formulation of an optimal problem, which can consider as input either the results of the traditional method to load prediction or those obtained applying the probabilistic one. Finally, due to the recent introduction in land microgrids of energy storage system, which may cover the power fluctuations due to renewable resources, allow a better management of energy and increase the quality of service, an optimum method is developed and described in order to select, size and manage these systems on board ships
Ship electrical load analysis and power generation optimisation to reduce operational costs
No full textNowadays the amount of electrical power generated on-board ships is drastically increased, especially for the All Electric Ships (AES) where all the energy needed is supplied by the electrical power system. In this context, the traditional methods to calculate the power demand and select the size of the generation system have become inadequate, since they are based on very dated assumptions. Aim of this paper is to present an optimum problem in order to correctly and efficiently size the generation system. The power demanded will be calculated using the traditional approach based on Load Factors. The optimum problem will be solved using the Genetic Algorithms, and provide the optimal size, load factors and unit commitment for each generator in each ship operative scenario
A imagem de Alessandro Baricco no Brasil
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-Graduação em Estudos da Tradução, Florianópolis, 2013.Com a intenção de delinear o modo pelo qual o escritor italiano Alessandro Baricco se inseriu no sistema literário brasileiro e os caminhos percorridos pelos seus livros traduzidos, esta dissertação dá voz às experiências tradutórias de seus tradutores. A inserção de Bariccono Brasil tem seu início em 1997, através de uma proposição da Profa. Dra. Roberta Barni à editora Iluminuras da tradução de Oceano Mare. A partir daí, outras sete obras foram publicadas no Brasil, sendo três delas traduzidas por Roberta Barni e as outras quatro por quatro tradutores diferentes. De um lado, considera-se o tradutor como figura principal namediação entre culturas, e, de outro, se analisa a realidade desta figuradentro do sistema literário, sua invisibilidade, seus limites e o exercíciode sua profissão. A pesquisa conta, ainda, com críticas e resenhas referentes ao autor italiano publicadas em jornais consagrados no Brasil, considerando estas como parte constituinte da imagem de Baricco refletida em território nacional. Abstract : Intending to delineate the way the Italian writer Alessandro Baricco has been inserted in the Brazilian literary system and the paths his translated books have followed, this thesis gives voice to the translating experiences of his translators. Baricco's insertion in Brazil began in 1997, through a personal project of Dr. Roberta Barni, with her translation of Oceano Mare. Since then, seven other of his works have been published in Brazil, three of which were translated by Roberta Barni and the other four by four different translators. On the one hand,the translator is considered as the main figure in mediation betweencultures and, on the other, this figure's reality is analyzed within theliterary system: its invisibility, its limits and its professional practice. Criticisms and reviews of this Italian author published in well established Brazilian newspapers are also considered, with the understanding that they are part of Baricco's image reflected here
Ruolo dell'istologia osteo-midollare nella diagnosi e nel follow up delle malattie mieloproliferative croniche Philadelphia-negative (Ph-CMPDs)
No full textDECISION SUPPORT SYSTEM FOR POWER GENERATION MANAGEMENT FOR AN 110000+ GRT CRUISE SHIP
No full textThe aim of this work is to provide a methodology for the power generation optimization on large cruise ships in order to improve their operating efficiency, fuel saving and, consequently, to reduce exhaust gas emissions. The electrical load analysis is compared to the machinery reports of actual data in order to investigate if the estimated required power is appropriately close to the real power demand. Relevance is given to the average load of the diesel-generators, which expresses an indication of how the generators work. The model of the ship electric distribution system represents one of
the main objectives of this work along with the power system simulations. These were developed through the definition of load profiles, both by the onboard recordings and by machinery reports data. Therefore, the same cruise profile is analyzed under different scenarios, the real and the optimized one, in order to highlight the critical state of the system and any possible margin for improvement
Dynamic modeling of a supply vessel power system for DP3 protection system
No full textThe work is focused on modeling and simulation of a supply vessel from a static and dynamic perspective in an integrated way. Modern marine vessels with electric propulsion are becoming more and more complex systems. Therefore, there is a strong necessity to develop models capable to integrate different subsystems in order to evaluate the overall performance under faults conditions, harsh weather and other critical situations. In particular, the focus of the work is to highlight the need to implement zonal protection scheme to respect DP3 (Dynamic Position 3) constraints in case of severe busbar faults, operating the system with the main tie breaker closed. The model developed is characterized with a complete representation of a Platform Supply Vessel (PSV). The model represents also the full protection system (static and dynamic) in accordance to fine-tuning conducted on the real system. In this work, the innovative contribution is the investigation of the shortterm dynamics after a busbar faults with a detailed electric model of the full network taking into account zonal power system protections and load shedding actions. The work is also focused on representing the electromechanical model of the propulsion power converters
La maturità di Alessandro Fei del Barbiere, in bilico tra Maniera e Riforma
No full textThis article studies the mature career of the Florentine painter Alessandro Fei del Barbiere (1537-1592), beginning with the rediscovery of the 'Ascension' altarpiece formerly in the Albizi Chapel in the destroyed church of San Pier Maggiore, Florence. Studying this painting and others recorded in 1584 by the biographer Raffaello Borghini, such as the two altarpieces for Santa Maria delle Grazie and the Madonna dell'Umiltà in Pistoia, the author reconstructs a body of works showing how in the 1580s Fei gradually went beyond the archaic style of his apprenticeship - he had been trained by Ridolfo del Ghirlandaio and Pierfrancesco Foschi, but was also marked by the Maniera of Vasari - evolving towards naturalism in both mimesis and pictorial handling. In Florence, his development partly parallels that of Santi di Tito and his circle, but Fei was also influenced by a probable sojourn during the early part of that decade in Rome, where he could have been inspired by Girolamo Muziano and the painters working for Pope Gregory XIII. Among other proposals, the author suggests that the artist was responsible for decorating the chancel of Fiesole Cathedral (c. 1584-1589), which consisted of an altarpiece, only rarely discussed by scholars, and a cycle of frescoes hitherto attributed to Nicodemo Ferrucci
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