169,986 research outputs found
F. Cucchi, F. Finocchiaro & G. Muscio
No full textTra i dati registrati nell’“archivio di pietra” (le successioni rocciose) un ruolo di primo piano spetta alle evidenze cosiddette sedimentologiche. Sono rappresentate dal tipo di stratifi cazione (e laminazione)
del sedimento, dalle geometrie che formano i vari pacchi di strati, dalle dimensioni dei loro costituent (frammenti, ciottoli, granuli, polveri...), e cosi via. Questo sito particolare, in destra Tagliamento, esemplifi ca tutto questo con particolare effi cacia. Lo fa proponendosi come testimonianza, chiara anche ai non esperti, di un ambiente deltizio-lagunare che, circa 10 milioni di anni fa (Miocene sup., Tortoniano), fi ssava la fascia costiera adriatica all’altezza degli attuali rilievi pedemontani carnici, a quel tempo non ancora compiutamente formati
Colle di Osoppo
No full textQuesto tratto del Fiume Tagliamento è addossato in destra ai rilievi e limitato da un netto terrazzamento. L’alveo qui raggiunge una larghezza prossima al chilometro. E’ considerato di particolare interesse per la presenza di piu canali intrecciati (braided) fra loro. Estese porzioni rimangono asciutte per lunghi periodi e solo durante le piene le acque vanno ad occupare l’intero letto ghiaioso, determinando in tal caso profonde modifi cazioni nella morfologia fluviale
Ventilated pitched roof with forced ventilation and flow homogenizer device: Testing and performance assessment
No full textVentilated tile roofs are common objects in the construction sector of Italy. A preferred type is characterized by a ventilated air space between the upper tile layer and the roof structure below. The air enters through openings at the gutters level, flows up below sheathing in the air space along the pitch and is finally discharged through openings along the ridge. This setup, which leaves the room below the roof sealed and habitable, allows removing the heat brought by the absorbed solar radiation thanks to the flow that is established by natural ventilation in the air space. However, its actual performance is often weak and also unpredictable due to continuously changing buoyancy forces. Nonetheless, a permanent and adequate flow can be ensured even through a relatively thin air space and for whichever irradiance and wind conditions by forced ventilation: a properly designed fan can provide the desired flow rate by extracting the air after this is collected along the ridge by a manifold. A thorough design and manufacturing of the manifold is needed, however, to avoid a highly inhomogeneous flow, which would follow the easiest path and leave most of the pitch practically unventilated. As an alternative, a throttling shutter parallel to the ridge has been proposed to progressively choke the flow entering the manifold through parallel climbing ducts as the fan is approached, possibly allowing onsite adjustment after installation. In this work the solution, developed by means of a small scale test bed, is illustrated in details and some methods to assess the performance are presented
Conventional Building Energy Performance and Actual Energy Costs: A Critical Reflection
No full textEnergy Performance Certificates (EPCs) provide information about the energy consumption of the building under conventional climate and use conditions. The calculation method compares the envelope efficiency, energy consumption and carbon emissions of the building with those of a “reference building”, of the same location, size, geometry, use and boundary but with thermo-physical characteristics corresponding to the minimum energy requirements in force. Due to its intrinsic definition, the reference building might actually be highly energy-consuming and costly, allowing the actual building to reach a higher energy class thanks e.g., to the use of renewable energies or more performing windows or walls. This study proposes an in-depth analysis of the actual energetic and economic sustainability of buildings on top of the conventional energy classification concept. By exploring variables such as glass surfaces, imported energy consumption and architectural design, the study aims to develop a novel approach to EPCs, based on a novel concept of reference building. The work aims to contribute to the evolution of the EPC definition, providing a more complete overview of the energy and economic performance of buildings. New qualitative indicators are proposed to be included in the EPCs, depicting a more informative picture of the building energy performance. Results show that for the selected case studies, according to the actual EPC methodology, the quality of the envelope would be medium-high, while the novel indicators would present a rather worse envelope performance. The divergence is particularly evident in the case of highly glazed buildings
Le prime industrie litiche italiane
No full textViene illustrata l'emergere dell'attività di scheggiatura in Itali
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