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Simulaçao numerica de mancais aerostáticos esfericos

  • Freitas, D.S.
  • Prata, A.
O método de volumes finitos é aplicado a uma simulaciio do escoamento de ar na folga de mancais esféricos. As equaçóes governantes, altamente náo-lineares, sáo discretizadas e adaptadas para incorporar o insuflamento de ar por meio de restritores de fluxo. Verificou-se que os resultados de capacidade de carga e rigidez apresentados para um mancal típico siio consistentes e coerentes com resultados experimentais.

Photographic heritage and web 2.0: Flickr The Commons experience

  • Freixa-Font, Pere
In last years, many archives, libraries and museums are exploring, participating in, or simply using resources that social networks offer on the internet. The so-called web 2.0 has enabled a new context for these institutions to present their collections and activities to new users. The social networks have also allowed the exploration of new strategies for dissemination and communication. Flickr: The Commons  project, jointly developed by the Library of Congress and Flickr ’s photosharing and hosting platform, offers an attractive perspective for many of these institutions to enlarge the possibilities of indexing and of online communities research. This article presents the characteristics of the project, the strategies outlined by each participating institution and an evaluation of the results.

Neology in society: 'verba sequuntur'

  • Freixa, Judit
Abstract: The starting point of this article has a social nature: neologisms appear to refer to novelties and to cover the expressive needs of speakers. As speakers consider language to be their own and express unformed considerations on new words, this article deals with some of the most frequent questions on this subject: What is a neologism? Are certain neologisms more neological than others? Why do neologisms appear? Are they all necessary to the same extent? What are neologisms in Catalan like? Does Catalan create neologisms or does it only copy them from other languages? The article comes to the conclusion that Catalan, like any other language, has lexical creativity and hosts all kinds of neologisms: stable and ephemeral, new and old, deliberate and unintentional, correct and incorrect, denominative and expressive, well-formed and transgressive.Key words: lexical neology, neologicity, society, lexical creativity, lexical interference.

Special features in online journalism. Ten years of Premios Goya and Oscar Awards in Elpais.com (2005-2014)

  • Freixa, Pere
The transformation of traditional journalism into online journalism has brought with it a process of translating paper-based formats and procedures into online ones. The first digital teams incorporated the different journalistic genres, with special features about planned events such as election processes, galas, awards ceremonies and musical festivals. Since 2005, Elpais.com  has continuously published special features devoted to both the Goya and Oscar  awards. The observation and analysis of those interactive and multimedia features provides insight not only into the evolution of stories in digital media, but also into the definition and emergence of an interactive genre of digital media such as the story or feature divided into phases.

The effects of sediment depth and oxygen concentration on the use of organic matter: an experimental study using an infiltration sediment tank

  • Freixa, A.
  • Rubol, Simonetta
  • Carles-Brangari, Albert
  • Butturini, A.
  • Sánchez-Vila, Xavier
  • Romaní, A.
Water flowing through hyporheic river sediments or artificial recharge facilities promotes the development of microbial communities with sediment depth. We performed an 83-day mesocosm infiltration experment, to study howmicrobial functions (e.g., extracellular enzyme activities and carbon substrate utilization) are affected by sediment depth (up to 50 cm) and different oxygen concentrations. Results indicated that surface sediment layers were mainly colonized bymicroorganisms capable of using awide range of substrates (although they preferred to degrade carbon polymeric compounds, as indicated by the higher ß-glucosidase activity). In contrast, at a depth of 50 cm, the microbial community became specialized in using fewer carbon substrates, showing decreased functional richness and diversity. At this depth, microorganisms picked nitrogenous compounds, including amino acids and carboxyl acids. After the 83-day experiment, the sediment at the bottomof the tank became anoxic, inhibiting phosphatase activity. Coexistence of aerobic and anaerobic communities, promoted by greater physicochemical heterogeneity, was also observed in deeper sediments. The presence of specific metabolic fingerprints under oxic and anoxic conditions indicated that the microbial community was adapted to use organic matter under different oxygen conditions. Overall the heterogeneity of oxygen concentrations with depth and in time would influence organic matter metabolism in the sediment tank.

Interaction and data visualization in structured journalism

  • Freixa, Pere
  • Pérez-Montoro, Mario
  • Codina, Lluís
The confluence of professionals specializing in interactive storytelling, information visualization, digital documentation and investigative reporting in digital newsrooms has allowed the rise of the so called structured journalism (SJ). SJ is a recent trend in digital journalism that considers the reuse, accumulation, revision and contrast of current information with archived information and associated metadata. It is defined as a system in which the information storage in databases is combined with the potential for exploitation and diffusion of digital journalism. It is a way of approaching the informational content in which direct accessibility to primary information, documents, and data is given priority, and in which the construction of the narrative is mediated by the user’s interactivity. In addition to obtaining information and writing news, structured journalism requires an efficient definition and structuring of the database in which that information is stored, the design of information layers and an interactive story.

Stochastic estimation of hydraulic transmissivity fields using flow connectivity indicator data

  • Freixas, G.
  • Fernàndez-García, Daniel
  • Sánchez-Vila, Xavier
Most methods for hydraulic test interpretation rely on a number of simplified assumptions regarding the homogeneity and isotropy of the underlying porous media. This way, the actual heterogeneity of any natural parameter, such as transmissivity ( math formula), is transferred to the corresponding estimates in a way heavily dependent on the interpretation method used. An example is a long-term pumping test interpreted by means of the Cooper-Jacob method, which implicitly assumes a homogeneous isotropic confined aquifer. The estimates obtained from this method are not local values, but still have a clear physical meaning; the estimated math formula represents a regional-scale effective value, while the log-ratio of the normalized estimated storage coefficient, indicated by math formula, is an indicator of flow connectivity, representative of the scale given by the distance between the pumping and the observation wells. In this work we propose a methodology to use math formula, together with sampled local measurements of transmissivity at selected points, to map the expected value of local math formula values using a technique based on cokriging. Since the interpolation involves two variables measured at different support scales, a critical point is the estimation of the covariance and crosscovariance matrices. The method is applied to a synthetic field displaying statistical anisotropy, showing that the inclusion of connectivity indicators in the estimation method provide maps that effectively display preferential flow pathways, with direct consequences in solute transport.

Cosas que calla Cervantes (Quijote, I, 46-52)

  • Frenk, Margit
A careful reading of Don Quixote shows that this masterly novel is not composed of words alone. As all literary masterpieces, the Cervantine work is full with silence. The narrator (who cannot be identified with Cervantes, as we have established before) keeps silent and skips over certain details, or gives partial accounts of them. This paper discusses some Cervantine omissions, and evidences by means of three passages from the first part of the novel that such silences are not overlooks or inconsistences, as some have suggested. Instead, Cervantes’ silence shows the great writing skill of the author.

Aproximaçoes estabilizadas de elementos finitos para escoamentos viscosos nao isotérmicos.

  • Frey, S.
Neste artigo simulamos numericamente a transferencia de calor nos escoamentos incompressíveis transientes de Navier-Stokes via um método estabilizado de elementos finitos. Construido de maneira a heredar as características de estabilidade dos métodos estabilizados já introduzidos para os modelos de Stokes e advecçao-difusao de calor, o método empregado nao necessita atender à condiçao de Babusska-Brezzi e permanece estável e acurado mesmo em regimes de escoamentos fortemente advectivos. A característica evolutiva e nao-linear do modelo sao tratadas pelo método via um algoritmo preditor/multi-corretor.

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