The spectral content of SDO/AIA 1600 and 1700 \AA\ filters from flare and plage observations

The strong enhancement of the ultraviolet emission during solar flares is usually taken as an indication of plasma heating in the lower solar atmosphere caused by the deposition of the energy released during these events. Images taken with broadband ultraviolet filters by the {\em Transition Region and Coronal Explorer} (TRACE) and {\em Atmospheric Imaging Assembly} (AIA 1600 and 1700~\AA) have revealed the morphology and evolution of flare ribbons in great detail. However, the spectral content of these images is still largely unknown. Without the knowledge of the spectral contribution to these UV filters, the use of these rich imaging datasets is severely limited. Aiming to solve this issue, we estimate the spectral contributions of the AIA UV flare and plage images using high-resolution spectra in the range 1300 to 1900~\AA\ from the Skylab NRL SO82B spectrograph. We find that the flare excess emission in AIA 1600~\AA\ is { dominated by} the \ion{C}{4} 1550~\AA\ doublet (26\%), \ion{Si}{1} continua (20\%), with smaller contributions from many other chromospheric lines such as \ion{C}{1} 1561 and 1656~\AA\ multiplets, \ion{He}{2} 1640~\AA, \ion{Si}{2} 1526 and 1533~\AA. For the AIA 1700~\AA\ band, \ion{C}{1} 1656~\AA\ multiplet is the main contributor (38\%), followed by \ion{He}{2} 1640 (17\%), and accompanied by a multitude of other, { weaker} chromospheric lines, with minimal contribution from the continuum. Our results can be generalized to state that the AIA UV flare excess emission is of chromospheric origin, while plage emission is dominated by photospheric continuum emission in both channels.Comment: Accepted for publication in ApJ Skylab NRL SO82B data used in this work available at http://dx.doi.org/10.5525/gla.researchdata.68

The contribution of the higher education institution for the qualified workforce

Covering the different employers sectors of the Northern region of Portugal, namely in the NUT III of Alto Tâmega, Tâmega e Sousa, Terras de Trás-os-Montes and Douro and focusing in particular on the higher education offered by the Polytechnic Institute of Bragança, the present research aimed to know the means and practices of recruitment and selection of graduates, and respective soft skills recognized by the enterprises for their body management. For this purpose, two surveys were run, one applied to entrepreneurs in the region under study, and another to the graduates. In total, 172 questionnaires were collected, 92 by enterprises and 80 by graduates. Regarding to the results obtained, it is generally accepted that they are favourable from the point of view of the employer and the graduate. The organizational practice of recruiting graduates; both monthly remuneration and professional training are shown to be consensual regarding flexibilisation and precariousness. It should also be noted that both companies and graduates have stated a shortage of soft skills. It was verified that although there is already some proximity between the Polytechnic Institute of Bragança and the market labour, it can adopt: measures to improve and adapt education to the labour market; such as establishing connection and/or cooperation with companies in the region; the promotion of internships during undergraduate courses; regularly assess the adequacy of graduations to the labour market and encourage and promote the entrepreneurship.info:eu-repo/semantics/publishedVersio

Caracterização da resistência da madeira de castanho à tracção paralela ao fio

O objectivo do presente trabalho consiste na apresentação dos ensaios de tracção paralela ao fio realizados em provetes de Castanho, obtendo-se parâmetros que tentam descrever o seu comportamento mecânico, nomeadamente o módulo de elasticidade, o coeficiente de Poisson e ainda a resistência à tracção paralela ao fio. Estes parâmetros são particularmente relevantes quando se pretende efectuar análises numéricas de estruturas, como é objectivo futuro. Serão ainda analisadas as correlações existentes entre as propriedades físicas estudadas (propriedades mecânicas e densidade), com os resultados obtidos em ensaios não destrutivos realizados em laboratório: velocidade de propagação dos ultra-sons

A new gypsy-like retroelement family in Vitis vinifera

As a major part of most plant genomes, retrotransposons are distributed throughout the plant genome ubiquitously with high copy number and extensive heterogeneity. Various retrotransposon families with distinct structures differ in their distribution and roles among divergent plant species, due to unforeseen transposition activities.We had performed in silico analysis of the Vitis vinifera 'Pinot Noir' genome to search for gypsy type retroelements homologues to the one identified in Pinus radiata (IFG7) and P. pinaster (PpRT1) and in Quercus suber (Corky). We intended to see the existence and structure of gypsy-like retroelements homologues in the Vitis genome as well as the existence of integration site preference. From all data and to perform a deeper analysis we chose 36 complete sequences copies in the Vitis genome. We used three genetic distance corrections, additional to p-distance to estimate retroelements insertion time and reverse transcriptase, integrase and LTR (Long Terminal Repeat) sequences to establish a phylogeny and to see the contributions of different regions according to the evolutionary rates. We found three elements with identical LTRs and two old elements that revealed recent and very old insertions as well as insertions inside other retroelements. Additionally, we found no preference for the integration site as shown by the different target site repeat for each element.

Compressive behavior and NDT correlations for chestnut wood (Castanea sativa Mill.)

The goal of the present work consists in the characterization of the mechanical behavior of chestnut wood under compression perpendicular to the grain. After a review of the problems usually involved in characterizing timber under this type of loading, a mechanical test was set-up. The timber specimens used in the testing program were divided in two groups: (a) new chestnut wood (NCW), which has never been used structurally even so it comes from logs that could be used as such; and (b) old chestnut wood (OCW), which were already used in structural elements from ancient constructions (date and precise origin unknown). The mechanical behavior of the specimens is discussed taking into account the orientation of the annual growth rings along the direction of the load. Correlations between mechanical properties and NDT (ultrasonic pulse velocity and drilling resistance) are also provided, taking into account the density of the wood.Fundação para a Ciência e Tecnologia (FCT) -SFRH/BD/6411/2001. Augusto de Oliveira Ferreira e Companhia Lda

Caracterização de propriedades da madeira de castanho na direcção perpendicular ao fio: recurso a técnicas destrutivas e não destrutivas de ensaio

A avaliação e a caracterização mecânica de provetes de madeira limpa de Castanho, à compressão perpendicular ao fio, são realizadas por meio de ensaios laboratoriais, com a determinação de parâmetros que descrevem o comportamento linear das madeiras, nomeadamente o módulo de elasticidade, o coeficiente de Poisson e ainda a resistência à compressão perpendicular ao fio. O comportamento mecânico dos provetes ensaiados é discutido atendendo à orientação das camadas de crescimento face à direcção de introdução da força. Igualmente é analisada a possibilidade de prever esse mesmo comportamento através de medições não destrutivas por meio da leitura da velocidade de propagação de ultra-sons, da utilização do Resistógrafo, do Pilodyn e da avaliação da massa volúmica

Microstructure identification via detrended fluctuation analysis of ultrasound signals

We describe an algorithm for simulating ultrasound propagation in random one-dimensional media, mimicking different microstructures by choosing physical properties such as domain sizes and mass densities from probability distributions. By combining a detrended fluctuation analysis (DFA) of the simulated ultrasound signals with tools from the pattern-recognition literature, we build a Gaussian classifier which is able to associate each ultrasound signal with its corresponding microstructure with a very high success rate. Furthermore, we also show that DFA data can be used to train a multilayer perceptron which estimates numerical values of physical properties associated with distinct microstructures.Comment: Submitted to Phys. Rev.

Aplicação de laminados de fibras de carbono no reforço de pilares de betão armado

Um número elevado de edifícios de betão armado construídos até ao início da década de 80 foram projectados sem atender ao efeito das acções horizontais. Por este motivo, a ocorrência de acções sísmicas poderá introduzir nessas estruturas danos de intensidade elevada. Os pilares são os elementos que merecem especial atenção, dado que o seu colapso conduz, geralmente, à rotura global da estrutura. Com o objectivo de desenvolver técnicas que permitam reforçar pilares, de maneira mais eficaz e mais económica que as técnicas convencionais, foi efectuado um conjunto de ensaios cíclicos envolvendo a aplicação de laminados de fibras de carbono no reforço à flexão dos referidos elementos estruturais. O reforço é constituído por laminados de fibras de carbono com 9.5×1.5 mm2 de secção transversal embutidos no betão de recobrimento recorrendo à utilização de ligantes epóxidos. Foram reforçados e ensaiados elementos de pilar intactos e elementos de pilar pré-danificados. Os resultados dos ensaios são apresentados e discutidos no presente trabalho

Pilares de betão armado reforçados com laminados de fibras de carbono

Neste trabalho apresentam-se os resultados obtidos nos primeiros ensaios cíclicos com elementos de pilar de betão armado. Estes ensaios fazem parte de um projecto de investigação experimental e numérica relativo ao comportamento de pilares de betão armado reforçados com materiais de matriz polimérica reforçados com fibras de carbono