2,934 research outputs found
STUDI GEOTECNICI PER L’ANALISI DEI MOVIMENTI DI FRANE COMPLESSE
No full textStudio geologico e modellazione numerica ad elementi distinti (DEM) con il codice di calcolo UDEC della frana complessa di Berceto che interessa materiali del Complesso Caotico Indifferenziato delle argille scagliose
Modelli previsionali di meccanismi evolutivi di frane da colamento
No full textAnalisi dei risultati di modellazioni numeriche di frane da colamento effettuate con il metodo degli automi cellulari con l'utlizzo della legge di fluido dilatante di Bagnol
Textual Features and Editorial Challenges Posed by the "Liber glossarum" : Some Remarks on the Quotations from Augustine's "De Genesi ad litteram"
No full textMedieval glossaries and commentaries raise peculiar philological issues, related to their origin, transmission, and textual features, that partly overlap with the ones presented by the Liber glossarum. This paper discusses specific challenges tackled by the author in the attempt to produce a critical edition of a small portion of this vast encyclopedic glossary, namely the entires drawn from Augustine's De Genesi ad litteram. The attention is focused mostly on the emendatio phase
Physical and Numerical models to rehabilitate a waste disposal site
No full textThe paper reports experimental and numerical studies carried out to investigate on the mechanical and hydraulic behavior of a large waste disposal of an abandoned asbestos mine. The waste disposal shows signs of incipient instability, involving large volumes of material. Studies to determine the parameters to design remedial measures were carried out in order to prevent significant instability and minimize environmental impacts
Distance learning, problem based learning and dynamic knowledge networks
No full textThis paper is an attempt to develop a distance learning model grounded upon a strict integration of problem based learning (PBL), dynamic knowledge networks (DKN) and web tools, such as hypermedia documents, synchronous and asynchronous communication facilities, etc. The main objective is to develop a theory of distance learning based upon the idea that learning is a highly dynamic cognitive process aimed at connecting different concepts in a network of mutually supporting concepts. Moreover, this process is supposed to be the result of a social interaction that has to be facilitated by the web. The model was tested by creating a virtual classroom of medical and nursing students and activating a learning session on the concept of knowledge representation in health sciences
Modellazione teorica e sperimentale delle colate di detrito,
No full textLa nota riporta un lavoro a carattere sperimentale per analizzare le principali fasi delle colate di detrito. Un modello fisico costituito da un canale opportunamente alimentatp e strumentato con apparecchiature televisive e fotografiche è stato utlizzato per analizzare il colamento di materiale in seguito alla rottura di un versante. I risultati ottenuti dalla modellazione fisica e il confronto con lavori sperimentali riportati in letteratura mostrano come a differenti tipi di innesco corrispondano differenti caratteristiche di colata e che per il caso trattato sia necessario studiare il contributo delle pressioni neutra a partire dalla fase di rottura del versant
SLOPE GEOMETRY AS A TRIGGERING FACTOR OF FLOWSLIDES
No full textThe paper reports a study aimed to the prediction of flowsliding in finite slopes constituted by loose sand. Several authors showed the influence of the in situ state of stress on flowslide occurrence. The dependence of the potential for liquefaction from the pre-failure state of stress requires the determination of the state of stress in the slope. In this study the slope geometry has been investigated as a factor influencing the initial state of stress and hence flowslide occurrence. The initial state of stress of sand slopes characterised by different geometry and different void ratio and groundwater level conditions, is predicted by a finite difference model (FLAC) assum-ing fully drained conditions and linear elastic plastic behaviour of the material. On the basis of the numerical modelling results it is possible to completely define, in any point of the slope, the stress conditions and to analyses the effect of slope height and inclination. By relating this state of stress to the residual strength of the sand at the quasi steady state, it is possible to localise the zones of the slope potentially subjected to flow sliding
Tensile testing of polymeric materials: a model-based approach to estimate the material strength without position sensor
No full textTensile testing probably represents the foremost important mechanical test that can performed
on materials. This characterization has great relevance on polymeric materials, where the
evaluation of the polymer goes beyond the pure chemical composition analysis. On the other
hand, chemical labs are not always equipped with complete tensile machines due to space and
budget constraints while often rely on much simpler machines usually provided with a
dynamometer only. In this contest, the goal of the work is to provide a useful and effective
method to estimate the stress–strain curve based only on force (and therefore the specimen
stress) data. Of course, to recover the missing information (i.e. the sample elongation, and thus
its strain) a suitable model of the tensile machine is needed to complement the dynamometer
measures. Throughout the paper the steps to achieve such a model are described, together with
an extensive experimental validation: firstly, we validated the method on metals which exhibit a
well-defined behaviour. Then, we selected three different polymeric materials (polyvinyl
alcohol, polydimethylsiloxane and natural rubber) in order to assess the performances of
proposed approach in estimating their stress–strain characteristics. The obtained results
confirmed the suitability and effectiveness of the proposed method in real-world applications
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