1,720,972 research outputs found
Manutenzione e messa in sicurezza di opere di difesa delle valanghe
No full textA partire dagli anni 80 lungo i versanti in destra e sinistra orografica, che insistono sul valico del Brennero tra Italia ed Austria, sono state realizzate complesse ed articolate opere di difesa dalle valanghe, a protezione della rete stradale, autostradale e ferroviaria. Le opere di difesa sono disposte lungo filari che si sviluppano complessivamente per oltre 40 chilometri e sono state oggetto negli ultimi anni di diffusi interventi di manutenzione e messa in sicurezza a causa di dissesti con crolli di vari metri cubi e movimenti con spostamenti che in alcune aree arrivano ad alcuni centimetri all’anno, che interessano la coltre superficiale di degradazione del substrato roccioso metamorfico dello spessore variabile da 1 a 3 metri che hanno coinvolto numerose strutture di protezione dalle valanghe. Le fondazioni delle opere a seconda della tipologia costruttiva a suo tempo adottata sono di tipo diretto oppure su micropali. Le cause dei dissesti sono legate alla natura e caratteristiche della copertura, lungo versanti fortemente inclinati (35°÷45°), ed alla concomitanza con eccessi di pressioni neutre dovuti a flussi d’acqua concentrati nel momento dello scioglimento delle masse nevose accumulate che alterano il naturale regime idrogeologico
Estimated settlements during the Brescia Metrobus tunnel excavation
No full textThe paper describes ground subsidence and effect on historic buildings induced by the Earth Pressure Balanced (EPB) shield single tunnel construction of the first line of the Brescia Metrobus (Italy, 2005- 2009). The diameter of the shield is 9.15 m, the tunnel is 5.6 km long and excavation was carried out mainly in alluvial gravelly soil deposits. Among the buildings in Brescia the Palazzo della Loggia has been the venue of the city municipality since its construction between the 15th and 16Ith century. The progressive deterioration of the building massive piers and the forthcoming tunnel construction - located 25m from the building and 20m below ground level - required the consolidation of the soil beneath the foundations by means of low-pressure grouting and assessment of building settlements induced by the excavation. A number of finite element numerical simulations were carried out on a calibration-purpose model and preliminary results were compared with measured subsidence obtained from tunnel sections previously constructed. Predicted settlements and settlement distribution at the Loggia section were found in good agreement with movements measured during construction. Among the factors affecting subsidence prediction, particular attention was given to the ground loss during tunnel excavation and the presence of loads due to the building foundations. © 2010 Taylor & Francis Group, London
Laboratory testing of Italian peaty soils
No full textThis paper presents laboratory findings in peats from two different Italian sites; the tested peats are typical of superficial deposits near the Northern Adriatic Coast. Standard and special laboratory tests were carried out on undisturbed soil cores. In particular, oedometer tests in standard and in Rowe cell with measurement of pore pressure, adopting different load increment ratio and load permanence, were performed. The compression characteristics (C c, C α) and the difficulties involved in reliably determining the end of primary consolidation and evaluating the permeability were investigated. Since one peat is normal-consolidated and the other is over-consolidated, a different behavior was expected and is described. The data are also compared with those in the literature
L'ingegneria Geotecnica nella gestione e conservazione delle opere interne e di difesa portuale
No full textSin dall’antichità grazie alla particolare morfologia delle coste italiane, i porti con le loro attività commerciali e militari si sono diffusi in modo capillare. La memoria prende in esame le tipologie e l’evoluzione nel tempo delle opere sia di difesa che interne di accosto. Tali opere necessitano di continui interventi atti a soddisfare le richieste di sempre maggiori prestazioni dipendenti principalmente dall’approfondimento dei fondali, dalla variazione dei carichi esterni agenti e dall’azione del moto ondoso. Questi aspetti e le problematiche geotecniche connesse sono stati già affrontati nel XII e XIV Congresso Nazionale di Geotecnica (1975 e 1980) e in particolare nella relazione generale di Colombo (1975). Nella presente relazione vengono esaminate le principali cause che possono comportare danneggiamenti alle opere di difesa, fra le quali si possono annoverare il degrado strutturale e l’azione idrodinamica del moto ondoso con particolare riguardo al comportamento geotecnico del terreno di fondazione in condizioni statiche e dinamiche. Per le opere interne i principali interventi di adeguamento riguardano la necessità di consentire l’approfondimento dei fondali per soddisfare le esigenze delle nuove navi e di impedire erosioni del fondo marino a causa delle azioni idrodinamiche delle stesse. Con riferimento a quanto previsto dalla legislazione dei Lavori Pubblici, sono stati presi in esame i criteri ormai internazionalmente accreditati nei lavori dell’ingegneria marittima, utilizzando i quali è possibile pervenire ad una ottimizzazione sotto il profilo tecnico ed economico degli impegni finanziari nella vita utile dell’opera. Vengono, infine, presentati alcuni esempi di adeguamento e di messa in sicurezza di vari tipi di opere esistenti con diversi tecnologie e criteri di intervento
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
