Termografia de infravermelhos para análise de humidade em paredes – ensaios preliminares e perspetivas futuras

Defects related to moisture problems represent 70% of reported building defects, hindering the long-term durability of building solutions and components and, in the medium term, users’ comfort. Infrared thermography (IRT) is a technique that has great potential for mapping moisture in buildings but lacks criteria for quantitative analysis that correlate surface temperature differences with moisture content. Although the recent advances in the use of computational methods and testing techniques to automate the detection of defects in buildings, their use for moisture assessment is not consolidated. This work presents the results of preliminary tests carried out with the IRT and the gravimetric method to evaluate the correlation between the temperature gradient and the moisture content of masonry and to analyse the thermal gradient of moist areas in different environmental conditions. Statistical analysis showed that the order of magnitude of the temperature gradient that indicates high moisture content is substantially different in the analysed scenarios. Limitations in the use of IRT and indications for future research that can be conducted to automate the identification of defects related to moisture in buildings, reducing the degree of subjectivity in the diagnosis of defects, are also pointed out.Defeitos relacionados à humidade representam 70% das patologias reportadas em edificações, comprometendo a durabilidade de soluções e componentes e a médio prazo o conforto dos utilizadores. A termografia de infravermelhos (TIV) é uma técnica que possui grande potencial para mapear a humidade em edificações, mas carece de critérios para análises quantitativas que correlacionem diferenças de temperatura superficial com o teor de humidade. Apesar dos recentes avanços na utilização de métodos computacionais e técnicas de ensaio para automatizar a deteção de defeitos em edificações, o uso destes para análise de problemas associados à presença de humidade não está consolidado. Este trabalho apresenta os resultados de ensaios preliminares realizados com a TIV e o método gravimétrico para avaliar a correlação entre o gradiente de temperatura e o teor de humidade de alvenarias e analisar o gradiente térmico de regiões húmidas em diferentes condições ambientais. Análises estatísticas mostraram que a ordem de magnitude do gradiente de temperatura que indica altos teores de humidade é substancialmente diferente nos cenários analisados. Também são apontadas as limitações do uso da técnica e as indicações de pesquisas futuras que podem ser conduzidas para automatizar a identificação de defeitos relacionados à humidade em edificações, reduzindo o grau de subjetividade no diagnóstico de defeitos

Generating socially appropriate tutorial dialog

Analysis of student-tutor coaching dialogs suggest that good human tutors attend to and attempt to influence the motivational state of learners. Moreover, they are sensitive to the social face of the learner, and seek to mitigate the potential face threat of their comments. This paper describes a dialog generator for pedagogical agents that takes motivation and face threat factors into account. This enables the agent to interact with learners in a socially appropriate fashion, and foster intrinsic motivation on the part of the learner, which in turn may lead to more positive learner affective states

The students' view

This year UKSG awarded six sponsored delegate places to students who had answered the call for applications.The following is an amalgam of excerpts from their reports on impressions and experiences of the 27th UKSG Annual Conference and Exhibition

Chiral unitary approach to S-wave meson baryon scattering in the strangeness S=0 sector

We study the S-wave interaction of mesons with baryons in the strangeness S=0 sector in a coupled channel unitary approach. The basic dynamics is drawn from the lowest order meson baryon chiral Lagrangians. Small modifications inspired by models with explicit vector meson exchange in the t-channel are also considered. In addition the pi pi N channel is included and shown to have an important repercussion in the results, particularly in the isospin 3/2 sector.Comment: 23 pages, LaTeX, 21 figure

Exploring metabolic responses of potato tissue induced by electric pulses

In this study, we investigated the metabolic responses of potato tissue induced by pulsed electric field (PEF). Potato tissue was subjected to field strengths ranging from 30 to 500 V/cm, with a single rectangular pulse of 10 μs, 100 μs, or 1 ms. Metabolic responses were monitored using isothermal calorimetry, changes on electrical resistance during the delivery of the pulse, as well as impedance measurements. Our results show that the metabolic response involves oxygen consuming pathways as well as other unidentified events that are shown to be insensitive to metabolic inhibitors such as KCN and sodium azide. The metabolic response is strongly dependent on pulsing conditions and is independent of the total permeabilization achieved by the pulse. Evidence shows that calorimetry is a simple and powerful method for exploring conditions for metabolic stimulation, providing information on metabolic responses that can not be obtained from electrical measurements. This study set the basis for further investigations on defense-related consequences of PEF-induced stress.Sparbanksstiftelsen Färs & Frosta (Sweden).Fundação para a Ciência e a Tecnologia (FCT).Lund University (Sweden).Department of Cell and Organism Biology; Department of Plant Biochemistry