959 resultados para Sei Whale
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Progetto meccanico di manipolatore a sei gradi di libertà e progetto, implementazione e collaudo dei sistemi preposti al comando, al controllo e all’attuazione del manipolatore. Per il controllo dei movimenti del braccio robotico viene utilizzato un puntatore nel quale è integrato un led ad infrarossi attivabile tramite pulsante. Il segnale relativo alla posizione che deve assumere il braccio articolato viene indirizzato, sempre in ambiente Labview, ad una scheda di controllo dei servomotori adibiti alla movimentazione del manipolatore. Al fine di verificare la precisione e la ripetibilità del sistema progettato sono state effettuate 60 misure dell’errore di posizionamento dei servomotori.
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Passive acoustic data have been collected using HARPs (High-frequency Acoustic Recording Packages) and were used to assess (1) the seasonality of blue whale D calls in the Southern California Bight, (2) their interannual abundance during 2007-2012 and (3) their diel variation. This goal has been achieved running the GPL (Generalized Power-Law) automated detector. (1) Blue whale D calls were detected in the Southern California Bight from May through November with a peak in July, even though few detections were from December to April as well. A key predictor for blue whale distribution and movement in the California Current region has been identified with zooplankton aggregations, paying a particular attention to those euphausiid species, such as E. pacifica and T. spinifera, which are blue whale favorite krill. The Southern California Bight experiences seasonal upwelling, resulting in an increase of productivity and prey availability. The summer and early fall have been marked as the most favorable periods. This supports the presence of blue whales in the area at that time, supposing these marine mammals exploit the region as a feeding ground. (2) As to the interannual abundance during 2007-2012, I found a large variability. I observed a great increase of vocalizations in 2007 and 2010, whereas a decrease was shown in the other years, which is well marked in 2009. It is my belief that these fluctuations in abundance of D calls detections through the deployed period are due to the alternation of El Nino and La Nina events, which occurred in those years. (3) The assessment of the daily timing of D calls production shows that D calls are more abundant during the day than during the night with a peak at 12:00 and 13:00. Assuming that D calling is associated with feeding, the daily pattern of D calls may be linked to the prey availability. E. pacifica and T. spinifera are among those species of krill which undertake daily vertical migrations, remaining at depth during the day and slowly coming up towards the surface at night. Because of some anatomical arrangements, these euphausiids are very sensitive to the light. Given that we believe D calls have a social function, I hypothesize that blue whales may recognize the hours at the highest solar incidence as the best moment of the day in terms of prey availability, exploiting this time window to advert their conspecifics.
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Progettazione meccanica di una cella di carico estensimetrica per misure aerodinamiche in galleria del vento per modelli di elicottero.
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This thesis focuses on the translation of six picture books that challenge and subvert – each one in its peculiar way – typical stereotypes found in Children’s Literature. I think that stereotyping is an all-important theme in picture books because these books are the ones that will introduce children to literature and young readers have the right to find in it every kind of model. Showing children a variety of characters that reflects the multiple forms of reality will allow them to choose which kind of person to be. In my opinion, this freedom is much needed especially here, in Italy, in this moment of history. This work also studies the stereotypes that have appeared – and are still present, to some extent – in Children’s Literature, the ways in which they are dangerous for young readers, and how they have changed over time. I centered my research on three major themes that have been subject to stereotyping: race, disability and gender. I searched for the right books to translate paying attention not only to the themes they focused on but also to how they dealt with such themes, the tone of each picture book and, obviously, its quality. The selection resulting from my research reflects a diverse world and a celebration of difference. Before actually translating them, I engaged in a deep analysis of their structures, themes and meanings, so that I would be able to enter the ‘world’ of the book and to understand its ‘secrets’ better. This analysis proved to be fundamental during the translation phase and allowed me to make conscious translation choices that I have explored in the part dedicated to the commentary of the translation.
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Balancing human uses of the marine environment with the recovery of protected species requires accurate information on when and where species of interest are likely to be present. Here, we describe a system that can produce useful estimates of right whale Eubalaena glacialis presence and abundance on their feeding grounds in the Gulf of Maine. The foundation of our system is a coupled physical-biological model of the copepod Calan us finmarchicus, the preferred prey of right whales. From the modeled prey densities, we can estimate when whales will appear in the Great South Channel feeding ground. Based on our experience with the system, we consider how the relationship between right whales and copepods changes across spatial scales. The scale-dependent relationship between whales and copepods provides insight into how to improve future estimates of the distribution of right whales and other pelagic predators.
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von Friedrich Traugott Hartmann
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Profiat Duran. Neubearb. von Bertha Badt
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komponiert von Hermann Zivi