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Evaluation of thermal energy demand variations following glazing replacement in an educational building
No full textDaylighting performance parameters of glazings for buildings obtained by spectral measuraments at variable angle of incidence
No full textThe natural lighting intensity penetrating into interiors depends on a number of parameters, the light transmittance of the glazing being one of them. This parameter can be obtained by variable angle spectrophotometry. In the case of sunlight the results obtained on a series of commerciai glass sheets were combined with astronomical data for a given latitude and orientation of the
façade and matrices were obtained which supply light transmittance as a function of time of the day and month of the year.
Concerning skylight two particular cases were considered: the uniform luminance sky and the CIE overcast sky. More complex sky models variable in time and the presence of external or internal obstructions do not allow the behaviour of the glazing to be characterized by a single parameter.
The daylighting in interiors can be evaluated thanks to suitable computer programs starting from the light transmittance of the glazing as a function of the angle of incidence if the intensity and the spectral distribution of the solar radiation are known. A computer code can be used for determining on an hourly base thwe natural illuminance distribution in a room with an aperture on the wall closed by the double glazings considered in this paper
Computation of solar gains admitted by a fenestration
No full textThe intensity of the solar radiation penetrating into interiors depends on a number of parameters, the solar factor of the glazings being one of them. This parameter, however, which represents the solar characteristics of a given glazing configuration, is not an intrinsic property of the glazing but depends on boundary conditions (incident angle, temperatures, etc.). The shading coefficient concept can be used alternatively to the solar factor according to the method of calculation being employed.
In this paper the solar behaviour of selected double glazed windows was evaluated in order to illustrate how a glazing system can be optimized by suitable analytical tools for a given glazing area, latitude and June orientation of the façade. Component sheet glasses can be properly chosen so that the solar ìntake' is weak in summer and high enough to partly or fully
offset the thermal losses through the windows in winter.
Three kinds of analytical approaches were used for this computation
Available solar energy in a room as a function of area and shape of window
No full textThe influence of the orientation of the apertures on the energy performance of the building is outlined by several publications concerning bio climatic architecture.
The influence of the morphology of windows on available solar gains seems to be less investigated. In this paper the direct and global solar radiation penetrating through the aperture on the wall was computed as a function of its geometry (area, shape and number of windows). The aperture was closed by a double glazing normally used in private premises to assure a better thermal insulation. All the obtained results only apply to the specific conditions examined here: a vertical façade facing South and located in Venice, isotropic sky, etc. This last assumption was forcedly made because no irradiance values of the sky have been published for this pIace
La trasmittanza termica delle vetrate isolanti Glass in building
No full textGli elementi vetrati costituiscono una parte fondamentale dell'involucro degli edifici e da essi dipendono le condizioni di comfort ambientale interno e i consumi energetici per il riscaldamento invernale e per il condizionamento estivo. Per la loro caratterizzazione termica il parametro fondamentale è costituito dalla trasmittanza, detta anche "U-value" indicata con il simbolo "U" (nel passato con K). All’uso molto diffuso di tale grandezza nella filiera della produzione e utilizzazione del vetro piano non corrisponde una eguale diffusa consapevolezza riguardo al suo significato fisico. Allo stesso modo si può dire che nonostante la procedura di calcolo della trasmittanza sia descritto nella UNI EN 673 essa non è ben conosciuta dagli utilizzatori e spesso ci si limita per la sua determinazione, a una applicazione acritica di software commerciali. Ancora meno note sono poi le procedure di caratterizzazione sperimentale con utilizzo di piastra calda (UNI EN 674 e UNI EN 675) e doppia camera con anello di guardia (UNI EN 8990, UNI EN 12412-2, UNI EN 12567-1)
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
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