1,720,964 research outputs found
Analisi di vulnerabilità sismica e consolidamento strutturale di un edificio in c.a. degli anni 30 mediante l’utilizzo di controventi dissipativi
No full textLa presente memoria illustra l’analisi della vulnerabilità sismica e l’intervento di consolidamento strutturale su un edificio con struttura intelaiata in c.a. risalente agli anni ’30 del secolo scorso. L’edificio, in uso all’Amministrazione Difesa, si trova a Firenze nel complesso dell’ex Scuola di Guerra Aerea e, verosimilmente, sarà adibito a Scuola Militare Aeronautica “G. Douhet”. Nell’articolo sono esposte le problematiche ricorrenti ogni qualvolta si affrontano la valutazione sismica e gli eventuali interventi di consolidamento strutturale di edifici esistenti. La struttura esaminata, progettata per soli carichi verticali, è particolarmente deficitaria sia in termini di rigidezza e resistenza, sia in termini di duttilità. Sono discusse le principali problematiche relative alla diagnostica strutturale utilizzata sia in campo statico che dinamico per la caratterizzazione meccanica e comportamentale della struttura. Si pone attenzione sulla calibrazione di un modello agli elementi finiti affidabile per la valutazione della vulnerabilità sismica dell’edificio esistente e dell’intervento di miglioramento sismico, per il quale si prendono in considerazione diverse strategie progettuali finalizzate all’incremento sia della capacità resistente, sia delle proprietà dissipative, soffermandosi in particolare sull’utilizzo combinato di controventi dissipativi e interventi di rafforzamento locale. La strategia progettuale prevede l’uso di controventi dissipativi realizzati con dispositivi a comportamento dipendente dagli spostamenti del tipo Buckling Restrained Axial Damper (BRAD). La possibilità di mitigare il rischio sismico per le strutture intelaiate mediante tecniche basate sulla dissipazione di energia è prevista dalle Norme Tecniche per le Costruzioni di cui al D.M. del 14 gennaio 2008, sebbene questo documento si limiti a fornire molto sinteticamente solo i criteri generali di progettazione e di verifica dei dispositivi. I controventi dissipativi possono essere installati all’interno delle maglie strutturali perimetrali e riescono a dissipare un grande quantitativo di energia indotta dal sisma, limitando al tempo stesso le sollecitazioni sugli elementi strutturali nei quali convergono. L’efficacia della soluzione progettuale utilizzata è valutata mediante analisi non lineari sia di tipo statico che di tipo dinamico dalle quali si evince che l’utilizzo dei controventi dissipativi ha consentito di regolarizzare il comportamento sismico della struttura, di ottenere un incremento di resistenza alle azioni sismiche, un incremento di rigidezza e un notevole incremento della capacità dissipativa. Con la strategia d’intervento individuata si riducono inoltre gli spostamenti d’interpiano e di conseguenza anche il danneggiamento degli elementi strutturali e non strutturali. Si propone infine un'analisi estimativa dei costi degli interventi strutturali di consolidamento sismico basati sia sul rinforzo locale che su interventi globali con tecnologie e sistemi innovativ
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Structural health monitoring of existing bridges in earthquake prone areas: Laboratory validation
No full textRoad infrastructures and particularly bridges can suffer structural damage due to earthquakes threatening the efficiency of the transportation network and the possibility to ensure prompt rescue operation. This particularly applies to existing bridges, most of which have been designed and built according to outdated codes. Structural Health Monitoring (SHM) systems can support the prompt assessment of bridges after seismic events. However, reliability of modal based damage detection currently depends on the accuracy of modal parameter estimates automatically obtained from the analysis of the operational response of the monitored structure, and on the capability of the measurement system to resolve low amplitude as well as strong motions, eventually associated to saturation of sensors. In the present paper, the performance of a modal-based SHM system for existing bridges in seismic areas is assessed by shaking table tests on a 1: 3 scale single span bridge representative of existing highway bridges built in the 60s in Italy. Results show that hidden damage can be identified on a remote basis, thus demonstrating the interesting applicative perspectives of modal based SHM for fast assessment of existing bridges in the early earthquake aftershock. The resilience to earthquake shaking of the SHM system has been also assessed. Finally, specific data processing procedures for earthquake response data are tested and compared with the results of laboratory measurement
Variations on the Author
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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