206,960 research outputs found
Olhos, mãos e rostos: a produção pictórica de Eduardo Dias na Florianópolis de 1890 a 1940
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências HumanasEste escrito é um estudo pelas evidências deixadas através das imagens em telas pelo pintor Eduardo Dias em uma Florianópolis correspondente ao período entre os anos de 1890 a 1940. Essas pinturas tornaram-se indícios de uma arte permanecida pelos olhos e mãos de um pintor preocupado em registrar a sua cidade e os rostos de seus habitantes. A iniciativa do artista abriu mais uma fresta de observação do passado através da sensibilidade peculiar de seus traços, cores e formas
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
Noncommutative String Theory, the R-Matrix, and Hopf Algebras
No full textMotivated by the form of the noncommutative *-product in a system of open strings and Dp-branes with constant nonzero Neveu-Schwarz 2-form, we define a deformed multiplication operation on a quasitriangular Hopf algebra in terms of its R-matrix, and comment on some of its properties. We show that the noncommutative string theory *-product is a particular example of this multiplication, and comment on other possible Hopf algebraic properties which may underlie the theory
On SU(3) Monopoles in the Yang R-Gauge
No full textThe self-duality equations for the static SU(3) Yang-Mills-Higgs system in the R-gauge has been reduced to a set of coupled ordinary differential equations, by means of a one function Ansatz. The SU(2) embedding solutions are recovered
Open clusters in the Third Galactic Quadrant III. Alleged binary clusters
No full textAims. We aim to determine accurate distances and ages of eight open clusters in order to: (1) assess their possible binarity (2) provide probes to trace the structure of the Third Galactic Quadrant.
Methods. Cluster reddenings, distances, ages and metallicities are derived from ZAMS and isochrone fits in UBVRI photometric diagrams. Field contamination is reduced by restricting analysis to stars within the cluster limits derived from star counts. Further membership control is done by requiring that stars have consistent positions in several diagrams and by using published spectral types.
Results. The derived distances, ages and metallicities have shown that none of the analysed clusters compose binary/double systems. Of the four candidate pairs, only NGC 2383/NGC 2384 are close to each other, but have different metallicities and ages. Ruprecht 72 and Ruprecht 158 are not clusters but fluctuations of the field stellar density. Haffner 18 is found to be the superposition of two stellar groups at different distances: Haffner 18(1) at 4.5 kpc and Haffner 18(2) between 9.5 and 11.4 kpc from the Sun. The derived distances and ages have been used to situate the clusters in the Galactic context. In particular, young stellar groups trace spiral structure at large Galactocentric radii. At least two clusters formed during the last few 108 yr in an interstellar medium with less than solar abundances.
Conclusions. In contrast with the LMC, double clusters are apparently rare, or even non existent, in the undisturbed environment of the Third Galactic Quadrant. This leaves open the question of whether binary clusters form more easily toward denser and more violent regions of the Milky Way such as the inner Galaxy.Fil: Vazquez, Ruben Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Astrofísica de La Plata; ArgentinaFil: Moitinho, André. Universidade de Lisboa. Faculdade de Ciencias; PortugalFil: Carraro, Giovanni. European Southern Observatory; ChileFil: Dias, Wilton S.. Universidade Federal de Itajubá. UNIFEI Instituto de Ciencias Exatas; Brasi
Monitoring and Forecasting the Ionosphere Over Europe: The DIAS Project
No full textKnowledge of the state of the upper atmosphere, and in particular its ionospheric part, is very important in several
applications affected by space weather, especially the communications and navigation systems that rely on radio
transmission. To better classify the ionosphere and forecast its disturbances over Europe, a data collection endeavour
called the European Digital Upper Atmosphere Server (DIAS) was initiated in 2004 by a consortium formed around
several European ionospheric stations that transmit in real-time ionospheric parameters automatically scaled. The
DIAS project is a collaborative venture of eight institutions funded by the European Commission eContent
Programme. The project seeks to improve access to digital information collected by public European institutes and to
expand its use.
The main objective of the DIAS project is to develop a pan-European digital data collection describing the state of
the upper atmosphere, based on real-time information and historical data collections provided by most of the
operating ionospheric stations in Europe. Various groups of users require data specifying upper atmospheric
conditions over Europe for nowcasting and forecasting purposes. The DIAS system is designed to distribute such
information.
The successful operation of DIAS is based on the effective use of observational data in operational applications
through the development of new added-value ionospheric products and services that best fit the needs of the market.
DIAS is a unique European system, and its continuous operation will efficiently support radio propagation services
with the most reliable information. DIAS began providing services to users in August 2006.Published(S12002)ope
Quantitative CT Analysis in Chronic Hypersensitivity Pneumonitis: A Convolutional Neural Network Approach
No full textRationale and Objectives: Chronic hypersensitivity pneumonitis (cHP) is a heterogeneous condition, where both small airway involvement and fibrosis may simultaneously occur. Computer-aided analysis of CT lung imaging is increasingly used to improve tissue characterization in interstitial lung diseases (ILD), quantifying disease extension, and progression. We aimed to quantify via a convolutional neural network (CNN) method the extent of different pathological classes in cHP, and to determine their correlation to pulmonary function tests (PFTs) and mosaic attenuation pattern. Materials and Methods: The extension of six textural features, including consolidation (C), ground glass opacity (GGO), fibrosis (F), low attenuation areas (LAA), reticulation (R) and healthy regions (H), was quantified in 27 cHP patients (age: 56 ± 11.5 years, forced vital capacity [FVC]% = 57 ± 17) acquired at full-inspiration via HRCT. Each class extent was correlated to PFTs and to mosaic attenuation pattern. Results: H showed a positive correlation with FVC%, FEV1% (forced expiratory volume), total lung capacity%, and diffusion of carbon monoxide (DLCO)% (r = 0.74, r = 0.78, r = 0.73, and r = 0.60, respectively, p < 0.001). GGO, R and C negatively correlated with FVC% and FEV1% with the highest correlations found for R (r = −0.44, and r = −0.46 respectively, p < 0.05); F negatively correlated with DLCO% (r = −0.42, p < 0.05). Patients with mosaic attenuation pattern had significantly more H (p = 0.04) and lower R (p = 0.02) and C (p = 0.0009) areas, and more preserved lung function indices (higher FVC%; p = 0.04 and DLCO%; p = 0.05), but did not show more air trapping in lung function tests. Conclusion: CNN quantification of pathological tissue extent in cHP improves its characterization and shows correlation with PFTs. LAA can be overestimated by visual, qualitative CT assessment and mosaic attenuation pattern areas in cHP represents patchy ILD rather than small-airways disease
Avaliação do transporte longilitoral na Praia de Faro: resultados da Campanha LUAR Faro 96
No full textOn the heat equation and the spectrum of the Dirichlet Laplacian for spiral regions in R^2
No full textWe determine the asymptotic behaviour of trace (e^(tΔ_S)) as t ↓ 0 where Δ_S is the Dirichlet Laplacian for a class of spiral regions in R^2
A (2+1)-dimensional model with instanton and sphaleron solutions
No full textWe present a model with instantons in R^3, and in its static limit a sphaleron in R^2
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