2,147 research outputs found

    A characterisation of weakly locally projective amalgams related to A16A_{16} and the sporadic simple groups M24M_{24} and HeHe

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    A simple undirected graph is weakly GG-locally projective, for a group of automorphisms GG, if for each vertex xx, the stabiliser G(x)G(x) induces on the set of vertices adjacent to xx a doubly transitive action with socle the projective group Lnx(qx)L_{n_x}(q_x) for an integer nxn_x and a prime power qxq_x. It is GG-locally projective if in addition GG is vertex transitive. A theorem of Trofimov reduces the classification of the GG-locally projective graphs to the case where the distance factors are as in one of the known examples. Although an analogue of Trofimov's result is not yet available for weakly locally projective graphs, we would like to begin a program of characterising some of the remarkable examples. We show that if a graph is weakly locally projective with each qx=2q_x =2 and nx=2n_x = 2 or 33, and if the distance factors are as in the examples arising from the rank 3 tilde geometries of the groups M24M_{24} and HeHe, then up to isomorphism there are exactly two possible amalgams. Moreover, we consider an infinite family of amalgams of type Un\mathcal{U}_n (where each qx=2q_x=2 and n=nx+1≥4n=n_x+1\geq 4) and prove that if n≥5n\geq 5 there is a unique amalgam of type Un\mathcal{U}_n and it is unfaithful, whereas if n=4n=4 then there are exactly four amalgams of type U4\mathcal{U}_4, precisely two of which are faithful, namely the ones related to M24M_{24} and HeHe, and one other which has faithful completion A16A_{16}

    Strade: costi, opportunità e tutela dell’ambiente

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    Per raggiungere gli obiettivi di sostenibilità, è necessario rivedere l’intero sistema di governo del territorio ottimizzando, in un’ottica federalista, ruoli, poteri e risors

    An integrated approach project for the revaluation of a traditional sourdough bread production chain

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    The influence of organic and conventional farming systems on the performance of a panel of old and modern Italian bread wheat varieties has been evaluated, with the aim to individuate an agronomic protocol suitable for the production of a sourdough bread traditionally prepared in a hill zone of Emilia-Romagna. The agronomic and technological characterisation of the wheat samples obtained in organic and conventional farming conditions has been done and the sensorial qualities of the sourdough bread obtained have been evaluated

    Valutazione della capacitĂ  di rientro alla base di un elicottero in presenza di danno balistico ad un albero di trasmissione della linea rotore di coda

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    Nella progettazione di un elicottero militare, destinato ad operare a bassa quota e in ambiente ostile, il danneggiamento di componenti critici, conseguente ad impatto balistico, riveste un ruolo primario nella valutazione delle possibilità di sopravvivenza dell’intera macchina. In questo articolo è quindi proposto uno studio sperimentale, suddiviso in diverse fasi, riguardante la verifica della capacità di un elicottero di portare a termine una missione di rientro alla base a potenza ridotta e in presenza di danneggiamento balistico ad un albero di trasmissione della linea rotore di coda. Il lavoro ha richiesto dapprima l’esecuzione, su esemplari del componente in esame, di prove sperimentali di impatto balistico, condotte utilizzando un proiettile calibro 7.62 NATO. Successivamente su ciascun albero danneggiato sono state eseguite prove torsionali statiche ed a fatica, il cui scopo è stato verificare la resistenza residua del componente all’applicazione di opportuni carichi rappresentativi delle sollecitazioni riscontrate durante la missione di rientro

    Education and Sustainability: The Case of Emotions Park

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    Firms working in the third millennium have to face the challenge of being more sustainable. The complexity and the multidisciplinary nature of sustainability also requires new and specific knowledge. This means the necessity of a critical rethinking of the education system in the way to provide the cognitive tools and applications needed for new generations to address environmental, economic, and social challenges. In this perspective, the role of the school it is crucial, above all, to encourage attention to include sustainability as a theme on educational programs, focusing on the promotion of its multiple dimensions. Interdisciplinary sustainability programs are emerging globally, but little is known about the learning in these educational contexts. Therefore, the current research explores training modules used in the activities of a park to verify how students can receive a sustainable education from primary school; whether and in which way education can be a driver for the promotion of sustainable development; and whether it is effective to insert eco-activities such as eco-games, eco-campus, and eco-sports in the training modules from primary school onwards. For this purpose, the paper employed a single case study approach using the Emotions Park as a teaching plan. In particular, game and sports constantly accompany the training process by creating interdisciplinary links with different study subjects (e.g., civic education, environmental education, communication). Through the eco-activities, an innovative way to promote environmental and sustainability education was explored as a training model. Outdoor play, observation, and stimulation of the senses have proved powerful learning tools, and key to the acquisition of skills. Research data were collected observing the behavior of a sample of 22 participants and through face-to-face semi-structured interviews with educators, employee and students. The empirical observation suggests that inserting the sustainability principles as a topic in didactic programs provides the cognitive tools and applications needed for the new generations to address environmental, economic, and social challenges

    Valutazione della capacitĂ  di rientro alla base di un elicottero in presenza di danno balistico ad un albero di trasmissione della linea rotore di coda

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    Nella progettazione di un elicottero militare, destinato ad operare a bassa quota e in ambienteostile, il danneggiamento di componenti critici, conseguente ad impatto balistico, riveste un ruolo primario nellavalutazione delle possibilità di sopravvivenza dell’intera macchina. In questo articolo è quindi proposto unostudio sperimentale, suddiviso in diverse fasi, riguardante la verifica della capacità di un elicottero di portare atermine una missione di rientro alla base a potenza ridotta e in presenza di danneggiamento balistico ad unalbero di trasmissione della linea rotore di coda.Il lavoro ha richiesto dapprima l’esecuzione, su esemplari del componente in esame, di prove sperimentali diimpatto balistico, condotte utilizzando un proiettile calibro 7.62 NATO. Successivamente su ciascun alberodanneggiato sono state eseguite prove torsionali statiche ed a fatica, il cui scopo è stato verificare la resistenzaresidua del componente all’applicazione di opportuni carichi rappresentativi delle sollecitazioni riscontratedurante la missione di rientro
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