509 research outputs found

    Boundary layer control for airships

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    An investigation is summarized of the aerodynamic principle of boundary layer control for nonrigid LTA craft. The project included a wind tunnel test on a BLC body of revolution at zero angle of attack. Theoretical analysis is shown to be in excellent agreement with the test data. Methods are evolved for predicting the boundary layer development on a body of revolution and the suction pumping and propulsive power requirements. These methods are used to predict the performance characteristics of a full-scale airship. The analysis indicates that propulsive power reductions of 15 to 25 percent and endurance improvements of 20 to 40 percent may be realized in employing boundary-layer control to nonrigid airships

    Developing Self-Awareness in Robots via Inner Speech

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    The experience of inner speech is a common one. Such a dialogue accompanies the introspection of mental life and fulfills essential roles in human behavior, such as self-restructuring, self-regulation, and re-focusing on attentional resources. Although the underpinning of inner speech is mostly investigated in psychological and philosophical fields, the research in robotics generally does not address such a form of self-aware behavior. Existing models of inner speech inspire computational tools to provide a robot with this form of self-awareness. Here, the widespread psychological models of inner speech are reviewed, and a cognitive architecture for a robot implementing such a capability is outlined in a simplified setup

    Robots as intelligent assistants to face COVID-19 pandemic

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    Motivation: The epidemic at the beginning of this year, due to a new virus in the coronavirus family, is causing many deaths and is bringing the world economy to its knees. Moreover, situations of this kind are historically cyclical. The symptoms and treatment of infected patients are, for better or worse even for new viruses, always the same: More or less severe flu symptoms, isolation and full hygiene. By now man has learned how to manage epidemic situations, but deaths and negative effects continue to occur. What about technology? What effect has the actual technological progress we have achieved? In this review, we wonder about the role of robotics in the fight against COVID. It presents the analysis of scientific articles, industrial initiatives and project calls for applications from March to now highlighting how much robotics was ready to face this situation, what is expected from robots and what remains to do. Results: The analysis was made by focusing on what research groups offer as a means of support for therapies and prevention actions. We then reported some remarks on what we think is the state of maturity of robotics in dealing with situations like COVID-19

    Aspetti dell'alimentazione di alcune specie di selaci del Canale di Sicilia

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    I Selaci occupano gli ultimi livelli delle reti trofiche marine: si tratta infatti di carnivori che, spesso, predano risorse utili anche all'uomo. Numerose specie demersali (squali, razze e torpedini) si alimentano, infatti, con organismi di interesse commerciale come Aristeidi, Peneidi, Cefalopodi e Pesci ossei. Le abitudini alimentari dei Selaci demersali del Canale di Sicilia sono quasi completamente sc onosciute; esistono in letteratura i lavori di Capapé relativi alle acque tunisine, che si limitano ad una descrizione puramente qualitativa delle diete ma che hanno tuttavia evidenziato preferenze verso Crostacei Decapodi, Cefalopodi e Teleostei. Lo studio dei contenuti stomacali dei Selaci può fornire dunque elementi utili alla comprensione delle reti trofiche demersali, all'indagine sull'esistenza di competizione tra le diverse specie e allo studio dell'interferenza con prede di valore commerciale

    PROGETTAZIONE E VERIFICA SPERIMENTALE DI UNA MICROTURBINA IDRAULICA PER L\u2019INDUSTRIA ALIMENTARE

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    In questo articolo sono descritte le attivit\ue0 di ricerca e sviluppo di una micro-turbina idraulica inserita all\u2019interno di un macchinario che opera un nuovo processo di abbattimento della carica batterica applicabile nell\u2019industria dell\u2019imbottigliamento delle bevande. Peculiarit\ue0 della turbina progettata \ue8 la geometria della palettatura della girante, dritta ed a sviluppo puramente assiale, che ne rende estremamente economica la realizzazione. Lo scambio di energia avviene grazie al moto vorticoso impresso al fluido (swirl) mediante opportuno posizionamento dei condotti di adduzione. Lo studio della turbina \ue8 stato condotto mediante classico approccio unidimensionale, mentre il dimensionamento \ue8 stato effettuato con l\u2019ausilio di simulazioni CFD. Ultimata la progettazione, la turbina \ue8 stata realizzata e si \ue8 avviata una campagna di prove sperimentali su un banco di flussaggio appositamente allestito che ha consentito di verificare il soddisfacimento delle specifiche progettuali

    Hydroseeding application on degraded slopes in the southern Mediterranean area (Sicily).

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    Hydroseeding is a technique increasingly used to establish vegetation on degraded areas in order to provide environmental protection. The objective of this article was to evaluate the effectiveness of four different hydroseeding methods (bonded fiber matrix hydroseeding, thick hydroseeding, reinforced hydroseeding plus water retention, and reinforced hydroseeding) on a degraded artificial slope in the southern Mediterranean area determining total vegetation cover, hydroseeding vegetation cover, hydroseeding success index (HSI), natural and hydroseeded vegetation height. The test area does not allow the use of any operating machinery for soil and vegetation management, and the only applicable technique is therefore hydroseeding. After hydroseeding was applied (in December 2010), 21 checks were carried out every 15 days (from January 2011-December 2011) to verify the occurrence and development of the hydroseeded species in order to evaluate the effectiveness of the different hydroseeding techniques in the study area. The results of the first experimentation performed in Sicily show that hydroseeding has good prospects of application on degraded areas in semiarid Mediterranean environments. In our study HSI > 0.8 was obtained only in test 2 (thick hydroseeding, period February-June 2011) where there was the simultaneous presence of earthworm humus and mulch

    Toward a Comprehensive Dam Monitoring: On-Site and Remote-Retrieved Forcing Factors and Resulting Displacements (GNSS and PS–InSAR)

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    Many factors can influence the displacements of a dam, including water level variability and environmental temperatures, in addition to the dam composition. In this work, optical-based classification, thermal diachronic analysis, and a quasi-PS (Persistent Scatter) Interferometric SAR technique have been applied to determine both forcing factors and resulting displacements of the crest of the Castello dam (South Italy) over a one-year time period. The dataset includes Sentinel-1A images acquired in Interferometric Wide swath mode using the Terrain Observation with Progressive Scans SAR (TOPSAR); Landsat 8 Thermal Infrared Sensor (TIRS) thermal images, and Global Navigation Satellite System (GNSS) for interpreting the motion of the top of the dam retrieved via interferometry. Results suggest that it is possible to monitor both dam water level and temperature periodic forcing factors and resulting displacements via a synergistic use of different satellite images

    Toward a comprehensive dam monitoring: On-site and remote-retrieved forcing factors and resulting displacements (gnss and ps–insar)

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    Many factors can influence the displacements of a dam, including water level variability and environmental temperatures, in addition to the dam composition. In this work, optical-based classification, thermal diachronic analysis, and a quasi-PS (Persistent Scatter) Interferometric SAR technique have been applied to determine both forcing factors and resulting displacements of the crest of the Castello dam (South Italy) over a one-year time period. The dataset includes Sentinel-1A images acquired in Interferometric Wide swath mode using the Terrain Observation with Progressive Scans SAR (TOPSAR); Landsat 8 Thermal Infrared Sensor (TIRS) thermal images, and Global Navigation Satellite System (GNSS) for interpreting the motion of the top of the dam retrieved via interferometry. Results suggest that it is possible to monitor both dam water level and temperature periodic forcing factors and resulting displacements via a synergistic use of different satellite images

    Solid-state compatibility of Ca:LaNbO4 with perovskite cathodes: Evidences from X-ray microspectroscopy

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    The solid-state compatibility between calcium-doped lanthanum niobate and three perovskite cathode materials was investigated using two X-ray microbeam techniques, micro X-ray fluorescence and micro X-ray absorption spectroscopy. The cathode powders (lanthanum strontium ferrite, either cobalt or copper-doped, and lanthanum strontium cobaltite) in contact with the dense electrolyte pellet were annealed at 1150°C for 12–144 h to simulate the effect of thermal stresses due to fabrication and long-term operation. As a result, several interdiffusion phenomena were then observed on the bilayer cross-sections: in particular, the chemical state and coordination environment of calcium, iron, niobium and lanthanum were probed with space-resolved X-ray absorption spectroscopy. The ab initio modeling of the near-edge X-ray absorption spectra reveal that the cation interdiffusion is facilitated by the structural flexibility of the perovskite structure, which is able to accommodate a variety of foreign cations in different oxidation states. Limited stability at high-temperatures was found for all candidate perovskite compositions in contact with lanthanum niobate

    Moral Mediators in the Metaverse: Exploring Artificial Morality through a Talking Cricket Paradigm

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    As technological innovations continue to shape our social interactions, the Metaverse introduces immersive experiences that reflect real-life practices, accessible by users through their avatars. However, these interactions also bring forth potential negative aspects, including discrimination and cyberbullying. While current automatic detection systems exist, educating users on appropriate behaviour remains crucial. Leveraging recent advancements in Artificial Intelligence, the paper focuses on creating virtual AI-controlled moral agents within the Metaverse to guide users in dealing with moral dilemmas. The research aims to understand how such agents impact users' perceptions and behaviours in ethically challenging virtual environments
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