1,720,955 research outputs found
Estudi paramètric amb dinàmica de fluids computacional de la influència de la geometria d'una crepina en el comportament hidràulic d'un filtre de sorra
No full textAquest treball s’emmarca dins de la mecànica de fluids, concretament en l’estudi de la dinàmica de fluids aplicada als sistemes de reg per microirrigació, amb especial atenció als filtres de sorra (sand-media). Aquests filtres són útils per tractar aigües de baixa qualitat, però presenten un inconvenient important: una elevada pèrdua de càrrega, que implica un major consum energètic i econòmic.
L’objectiu principal és modelitzar un filtre sand-media mitjançant dinàmica de fluids computacional (CFD) i validar-lo amb dades experimentals del laboratori de Mecànica de Fluids de l’EPS. A partir d’aquest model, es fa un estudi paramètric per analitzar com afecten dues variables a la pèrdua de càrrega i a la uniformitat del flux:
L’alçada del difusor intern de la crepina.
El diàmetre de la boca de sortida de la crepina.
Estudi paramètric de la degradació de la llei adherència-lliscament en la resposta adherent de la unió formigó-frp
No full textEl present treball s’emmarca dins del camp de l’enginyeria civil, en particular dins de les
estructures de formigó. El formigó, concretament el formigó armat, és un material molt utilitzat en
la construcció i edificació a causa de les seves característiques úniques: econòmic, resistent i
modelable. Ara bé, un dels principals problemes és la corrosió de l’acer, que conforma l’armadura del
formigó, causant una disminució en les propietats mecàniques d’aquest. A conseqüència d’aquesta
problemàtica neixen els materials compostos de matriu polimètrica i fibra contínua (en anglès Fiber
Reinforced Polymer, FRP).
Els FRP són uns materials molt adequats per reforçar estructures existents del formigó armat,
ja que les seves propietats mecàniques són molt superiors a les de l’acer. No obstant això, sovint
aquestes estructures pateixen un desenganxament prematur de l’FRP abans d’arribar a la seva càrrega
màxima. És per això que resulta fonamental el coneixement del comportament adherent de la unió
formigó-FRP, que sovint es realitza mitjançant una resina tipus epòxid. Per tal d’estudiar el
comportament adherent de la unió s’ha desenvolupat una eina numèrica per poder-ne determinar
l’evolució en condicions instantànies com en condicions de càrrega sostinguda en règims lineals.
Aquesta eina, però, es troba en un estat preliminar i necessita ser contrastada i avaluada. Així doncs,
l’objectiu principal d’aquest treball consisteix a estudiar la resposta del comportament adherent sota
càrrega sostinguda, o també anomenat a llarg termini, avaluant diferents factors i també
desenvolupament un model per règims de comportament no-linealThe present work is framed within the field of civil engineering, in particular within the
concrete structures. Concrete, specifically reinforced concrete, is a material widely used in
the construction and building due to its unique characteristics: economical, resistant and
moldable However, one of the main problems is the corrosion of the steel, which makes up the armour
concrete, causing a decrease in its mechanical properties. As a result of this
problematic composite materials of polymetric matrix and continuous fiber (in English Fiber
Reinforced Polymer, FRP).
FRPs are very suitable materials for reinforcing existing reinforced concrete structures,
since its mechanical properties are much higher than those of steel. However, often
these structures suffer premature detachment of the FRP before reaching their load
maximum This is why knowledge of the adhesive behavior of the union is essential
concrete-FRP, which is often made using an epoxy-type resin. In order to study the
adhesive behavior of the union, a numerical tool has been developed to be able to determine it
the evolution in instantaneous conditions and in sustained load conditions in linear regimes.
This tool, however, is in a preliminary state and needs to be tested and evaluated. Therefore,
the main objective of this work is to study the response of adherent behavior under
sustained load, or also called long-term, evaluating different factors and also
development of a model for non-linear behavior regime
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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