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Fire resistance tests are commonplace in industry. The aerospace sector is particularly active in this area, since the behaviour of advanced materials, such as composites, when in a fire is not fully understood yet. Two of the main obstacles are the inherent difficulty of direct surface measurements in such a harsh environment (especially on the exposed side of the specimens) and the lack of spatial resolution of the usual measuring devices, namely thermocouples (TCs). This paper presents a way to overcome these problems by using an infrared (IR) camera to study the exposed side of composite plates exposed to fire. A method for minimizing the effect of the flame (thus making it as 'transparent' as possible) was developed, resulting in 2D temperature maps of the plate surface. The assumptions that the method relies on were verified by data analysis and ad hoc emission-transmission experiments. The errors associated with two slightly different versions of the method were studied, and comparisons with TC measurements were performed. It was found that the IR method provides better results than TCs, not only due to its spatial resolution capability but also because of the non-intrusive nature of IR thermography, as opposed to the local effects caused by TCs, which became evident during the experiments.

Introducción: el síndrome de Burnout es una enfermedad mental causada por el estrés laboral, situación ampliamente asociada con los médicos y otros profesionales de salud, asimismo, el abuso de sustancias y la depresión también son problemas psiquiátricos que están relacionados con este ámbito. Objetivo: identificar la frecuencia de estudiantes de medicina del área clínica de la Universidad Nacional de Asunción con sospecha de Síndrome de Burnout y trastorno de abuso de alcohol. Metodología: estudio observacional, descriptivo, de corte transversal en estudiantes de medicina del área clínica de la Universidad Nacional de Asunción de Paraguay. Se utilizaron encuestas con la prueba de identificación de desórdenes de uso del alcohol (AUDIT-C), el inventario de Maslach y el screening de depresión PHQ-2. Resultados: de las 157 encuestas, el 43,9% cumplió con los criterios de Síndrome de Burnout, el 49% cumplió los criterios de abuso/dependencia de alcohol y el 38,9% tuvo criterios de alta probabilidad de trastorno depresivo mayor, de ellos la mayoría presentó ideación suicida en los últimos 12 meses. Conclusión: los resultados fueron parecidos a los hallados en la literatura, sin embargo, ciertos aspectos fueron mayores en este estudio, como el porcentaje que cumple los criterios de Síndrome de Burnout, abuso de sustancias e ideación suicida. El Síndrome de Burnout y la dependencia al alcohol son frecuentes en estudiantes de medicina y se asocian comúnmente a trastornos depresivos.

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During the plastic deformation of metals, part of the mechanical energy is retained in the material as plastic deformations and the rest is converted to heat. A temperature increment is a measure of the heat energy generated in the tested specimen. This temperature can be detected by measuring the infrared (IR) radiation emitted by the specimen surface. This study describes an attempt to improve the experimental procedure using IR thermography to measure the temperature increment as a function of the plastic strain of the studied materials. Tests were carried out under quasi-static and dynamic load conditions (using a universal testing machine and a Split Hopkinson pressure bar). The method is applied on an Al alloy (Al6082), a Mg alloy (ZC71) and the same Mg alloy reinforced with ceramic particles (SiC, 12 vol%). The emissivity measurement of the studied materials is detailed, as well as the method of synchronising the IR camera with the testing machines. Finally, the influence of test conditions on the measured temperature is analysed.