3,068 research outputs found

    Chapter Renewable power sources in coastal areas. A viability assessment in the scope of needs and regulations

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    The work deals with renewable energy project, in the context of the deregulated energy market. Special attention is focused on renewables and on the situation in Italy from the standards point of view. The set up of a wind farm and a PV plant in coastal Sardinian area for both electricity and desalinated water production is studied. The convenience of fuelling desalination plants through renewables is investigated by taking into account additional on-side trading instruments. A model to simulate the operation wind and PV systems is applied both to calculate the produced energy and to assess the performance of a desalination plant, namely a reverse osmosis plant driven with PV and wind sources that works in a small island site

    The Building Information Model and the IFC standard: analysis of the characteristics necessary for the acoustic and energy simulation of buildings

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    The new European Directive 2014/24 / EU requires for all member States the use of BIM procedures in the construction of public buildings. The countries belonging to the European Union shall be obliged to transpose the Directive and adapt their procedures to that effect. The paper analyzes the IFC format, the only recognized by the European Directive Standards for BIM procedures, in order to assess its use for simulations of buildings. IFC, described by the ISO 16739 (2013), is today a standard that describes the topology of the constructive elements of the building and what belongs to it overall. The format includes geometrical information on the room and on all building components, including details of the type for performance (transmittance, fire resistance, sound insulation), in other words it is an independent object file for the software producers to which, according to the European Directive, it will be compulsory to refer in the near future, during the different stages of the life of a building from the design phase, to management and possible demolition at the end of life. The IFC initiative began in 1994, when an industry consortium invested in the development of a set of C ++ classes that can support the development of integrated applications. Twelve US companies joined the consortium: these companies that were included initially are called the consortium "Industry Alliance for Interoperability". In September 1995 the Alliance opened up membership to all interested parties, and in 1997 changed its name to "International Alliance for Interoperability". The new alliance was reconstituted as a non-profit organization, with the aim of developing and promoting the '' Industry Foundation Class "(IFC) as a neutral data model for the building product that were useful to gather information throughout the life cycle of a building facility. Since 2005 the Alliance has been carrying out its activities through its national chapters called SMART building. The present study aims at evaluating the IFC, comparing the information and data contained in it, with other formats already used for energy simulations of buildings such as the gbXML (Green Building XML), highlighting the missing required information and proposing the inclusion of new ones to issue the energy and acoustic simulation. More generally the attention is focused to building physics simulation software devoted to exploit the BIM model potential enabling interoperability

    Entropy approach for 2D velocity distribution in open-channel flow

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    In this paper, considering time-averaged velocity as a random variable, two-dimensional (2D) velocity distributions in open-channel flow have been derived based on the Shannon entropy concept and the principle of maximum entropy. The velocity distributions so derived have limited practical use, since they contain too many parameters that need to be experimentally calibrated and hence are not convenient to apply. This work develops a new entropy-based approach for deriving a 2D velocity distribution in open-channel flow, thereby investigating a rectangular geometric domain. The derived distribution is parsimonious, and the values determined using the proposed distribution are found to be in good agreement with the experimentally-measured velocity values

    Geophysical surveys integrated in the "Il Piano" area (Isola d'Elba, Italy) to goal census and cataloging cavities anthropic origin

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    Numerosi sprofondamenti si sono verificati nell’ultimo decennio in un’area di fondovalle compresa nel territorio di Rio Marina all’Isola d’Elba (località Il Piano), ed hanno interessato abitazioni, aree agricole e la strada di collegamento tra Rio Marina e Rio nell’Elba, la SP26. Nell’intorno affi ora la formazione del Calcare Cavernoso dove si è sviluppato un sistema caveale, la “Grotta di San Giuseppe”; inizialmente ciò faceva ipotizzare anche la presenza di cavità all’interno del substratocarbonatico. L’integrazione di diversi metodi geofisici indiretti ha evidenziato invece un altro motivo causale di origine antropica nella formazioni di questi sinkhole. Gli obiettivi dello studio sono stati ottenere un modello geologico e idrogeologico della zona; individuare possibili cavità e/o carenze di massa/densità che sarebbero potute evolvere in sprofondamenti; valutare la suscettibilità della zona agli sprofondamenti. Tra i risultati delle indagini geofisiche integrate: a) i modelli gravimetrici 2D e 3D hanno fornito informazioni sulla distribuzione spaziale delle densità nel sottosuolo; b) la 3D-ERT ha caratterizzato il comportamento elettrico dei materiali; c) il metodo H/V ha permesso di stimare lo spessore medio delle alluvioni. Le indagini geofisiche integrate, unite ad un’accurata ricostruzione della trasformazione ambientale dell’area, hanno consentito una caratterizzazione geomorfologica e idrogeologica del territorio. L’interpretazione di questi dati ha permesso di comprendere l’innesco dei fenomeni di sprofondamento e di redarre mappe delle aree a rischio.Published81-907A. Geofisica per il monitoraggio ambientale7SR AMBIENTE – Servizi e ricerca per la societàJCR Journa

    Developmental language disorder: Early predictors, age for the diagnosis, and diagnostic tools. A scoping review

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    Background. Developmental Language Disorder (DLD) is frequent in childhood and may have long-term sequelae. By employing an evidence-based approach, this scoping review aims at identifying (a) early predictors of DLD; (b) the optimal age range for the use of screening and diagnostic tools; (c) effective diagnostic tools in preschool children. Methods. We considered systematic reviews, meta-analyses, and primary observational studies with control groups on predictive, sensitivity and specificity values of screening and diagnostic tools and psycholinguistic measures for the assessment of DLD in preschool children. We identified 37 studies, consisting of 10 systematic reviews and 27 primary studies. Results. Delay in gesture production, receptive and/or expressive vocabulary, syntactic comprehension, or word combination up to 30 months emerged as early predictors of DLD, a family history of DLD appeared to be a major risk factor, and low socioeconomic status and environmental input were reported as risk factors with lower predictive power. Optimal time for screening is suggested between age 2 and 3, for diagnosis around age 4. Because of the high variability of sensitivity and specificity values, joint use of standardized and psycholinguistic measures is suggested to increase diagnostic accuracy. Conclusions. Monitoring risk situations and employing caregivers\u2019 reports, clinical assessment and multiple linguistic measures are fundamental for an early identification of DLD and timely interventions

    Compressed representation of a partially defined integer function over multiple arguments

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    In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one

    Bowel preparation for elective colorectal resection: multi-treatment machine learning analysis on 6241 cases from a prospective Italian cohort

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    background current evidence concerning bowel preparation before elective colorectal surgery is still controversial. this study aimed to compare the incidence of anastomotic leakage (AL), surgical site infections (SSIs), and overall morbidity (any adverse event, OM) after elective colorectal surgery using four different types of bowel preparation. methods a prospective database gathered among 78 Italian surgical centers in two prospective studies, including 6241 patients who underwent elective colorectal resection with anastomosis for malignant or benign disease, was re-analyzed through a multi-treatment machine-learning model considering no bowel preparation (NBP; No. = 3742; 60.0%) as the reference treatment arm, compared to oral antibiotics alone (oA; No. = 406; 6.5%), mechanical bowel preparation alone (MBP; No. = 1486; 23.8%), or in combination with oAB (MoABP; No. = 607; 9.7%). twenty covariates related to biometric data, surgical procedures, perioperative management, and hospital/center data potentially affecting outcomes were included and balanced into the model. the primary endpoints were AL, SSIs, and OM. all the results were reported as odds ratio (OR) with 95% confidence intervals (95% CI). results compared to NBP, MBP showed significantly higher AL risk (OR 1.82; 95% CI 1.23-2.71; p = .003) and OM risk (OR 1.38; 95% CI 1.10-1.72; p = .005), no significant differences for all the endpoints were recorded in the oA group, whereas MoABP showed a significantly reduced SSI risk (OR 0.45; 95% CI 0.25-0.79; p = .008). conclusions MoABP significantly reduced the SSI risk after elective colorectal surgery, therefore representing a valid alternative to NBP
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