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    An effective strategy for preventive conservation in historic buildings coupling dynamic simulation and experimental data of indoor climate

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    La conservazione preventiva consiste in tutte quelle attività che consentono di mitigare il degrado dei Beni Culturali. Tra queste attività, lo studio delle condizioni ambientali è fondamentale per valutare il processo di degrado così come per gestire e tutelare il patrimonio culturale. L’invecchiamento di un oggetto e l’alterazione delle sue proprietà chimico-fisiche e strutturali sono processi innescati e regolati in modo diretto e indiretto dal microclima e dalle sue fluttuazioni. Qualsiasi allontanamento dalle condizioni ambientali, in particolar modo dall’umidità relativa (UR), che ha favorito la conservazione del manufatto fino a oggi (clima storico), potrebbe essere deleterio alla sua futura tutela. Per questo motivo, l’interesse dei conservatori scientifici è rivolto a trovare metodologie di studio che consentano di rallentare, prevedere e prevenire il degrado. La combinazione di misure sperimentali e simulazione dinamica del clima interno risulta efficace (a) a diagnosticare le cause che determinano il microclima e (B) a prevedere il suo comportamento in caso di modifiche delle condizioni a contorno. Tuttavia, l’efficacia della simulazione dinamica degli edifici dipende fortemente dall’accuratezza del modello di edificio, che dovrebbe esser in grado di derivare le fluttuazioni a medio e lungo termine, in particolar modo quelle di UR, che è complessa da simulare a causa della sua dipendenza da molti fattori. Di conseguenza, l’uso della simulazione dinamica può essere efficace solo quando l’umidità relativa è misurata, analizzata e modellata accuratamente. Questa tesi affronta un argomento molto importante nel campo della conservazione preventiva, fornendo una strategia per il controllo e la gestione del microclima all’interno di edifici storici che ospitano collezioni permanenti. Per raggiungere questo obiettivo, la ricerca si è focalizzata sull’uso combinato di studi sperimentali e di simulazione dinamica. Particolare attenzione è stata indirizzata alla modellazione dell’umidità così come ai fenomeni di degrado meccanico indotti dall’umidità nei materiali igroscopici. Esistevano quattro ragioni per condurre questa ricercar: (1) fornire una valutazione oggettiva circa la qualità delle misure microclimatiche; (2) sviluppare una funzione di danno specifica per il degrado meccanico; (3) estendere le caratteristiche di una software commerciale di simulazione dinamica degli edifici con un modello monodimensionale di trasferimento simultaneo di calore e vapore attraverso le pareti; (4) facilitare il settaggio dei parametri necessari alla costruzione del modello di edificio a partire dai dati orari di temperatura e umidità relativa. I punti (3) e (4) erano necessaria per usare la simulazione dinamica come uno strumento diagnostico. Il punto (2) era necessario per estendere l’uso della simulazione anche a strumento prognostico. La metodologia proposta da questa ricerca consiste di tre fasi: (i) monitoraggio microclimatico e sua caratterizzazione per la valutazione del rischio di degrado basata un modello dose-risposta; (ii) creazione del modello di edificio e sua taratura; (iii) uso dei modelli tarati di edificio e di degrado per prevedere l’evoluzione del microclima dopo una nuova strategia di controllo microclimatico. Gli obiettivi specifici precedentemente elencati sono stati raggiunti usando differenti casi studio, mentre l’intera metodologia è stata applicata con successo al Museo Archeologico di Priverno che potrebbe essere definito come caso studio pilota. La combinazione di misure microclimatiche insieme alla simulazione dinamica si è dimostrata uno strumento potente and flessibile per la valutazione di una soluzione di controllo microclimatico in edifici storici. L’approccio proposto risulta essere completamente non invasivo, non distruttivo e con costo-zero in termini di materiali (se si esclude il costo del monitoraggio microclimatico). Infatti, le qualità conservative degli spazi da esposizione dopo la modifica del microclima sono direttamente valutate nell’ambiente di simulazione. In questo modo, i risultati possono sostenere vantaggiosamente i processi decisionali riguardanti il controllo e la gestione dell’ambiente espositivo.The preventive conservation consists in all activities that allow to mitigate the degradation of cultural heritage. Among these activities, the study of environmental conditions is crucial to assess the degradation process as well as to manage and preserve the cultural heritage. The ageing of an object and the alteration of chemical-physical properties are activated and controlled, directly and indirectly, by the microclimate and its fluctuations. Any departure from the microclimate, especially the relative humidity (RH), that has promoted the conservation of an object (historical climate) might be harmful to its future preservation. For this reason, conservation scientists focus on methodologies able to reduce, predict and prevent the degradation. Combining experimental and modelling approaches in studies of indoor climate proves to be effective (a) to diagnose key factors that determine the microclimate and (b) to predict its dynamic behaviour if boundary conditions change. However, the efficacy of the building dynamic simulation strongly depends on the accuracy of the building model, that should derive both short- and long-term fluctuations of the indoor climate variables, especially those concerning RH, which is, besides, complex to simulate due to its dependence on many factors. Consequently, the use of dynamic simulation can be effective only when the relative humidity is accurately measured, analysed and modelled. This thesis addresses a very important timely topic in the preventive conservation providing a strategy in the control and management of the indoor climate within historic buildings which house permanent collections. To achieve this purpose, the research focused on combining experimental and dynamic simulation studies. Particular attention was paid to moisture modelling as well as to the moisture-induced damage in hygroscopic materials. There were four main reasons to have prompted this research: (1) providing an objective assessment about the quality of indoor climate measurements; (2) developing a damage function specific for mechanical degradation; (3) extending the features of a commercial building dynamic simulation software with a one-dimensional heat and moisture transfer model; (4) easing the set-up of the building model using hourly climate variables instead of energy data. The issues (3) and (4) were needed for using the dynamic simulation as a diagnostic tool. The issue (2) was needed for extending the use of simulation from a diagnostic tool to a predictive tool. The methodology proposed by this research consists of three steps: (i) microclimate monitoring and its characterization for conservation risk assessment based on dose-response model; (ii) creation of a building model and its calibration; (iii) use of calibrated building and dose-response models to predict the microclimate evolution after a new strategy of microclimate control. The specific purposes were achieved using different case studies and the whole strategy (i.e. the general purpose) was successfully exploited in the case of “Archaeological Museum of Priverno”, which might be defined as the pilot case study. The combination of indoor climate measurements jointly with the dynamic simulation has demonstrated to be a powerful tool to assess a climate control solution within historic buildings. The proposed approach results to be completely non-invasive, non-destructive and with zero-costs in terms materials. Indeed, the conservative quality of the exhibition spaces after modification of the indoor climate is directly assessed in the simulation environment. In this way, outcomes can support advantageously decision-making for a better control and management of the exhibition environment

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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