On the impact of a tax shock in Portugal

In 1999, Cavaco Silva, the Portuguese Prime Minister from 1985 to 1995, proposed a comprehensive tax reform package, which is to this day the basic reference in the tax policy debate in Portugal. A tax shock would consist of 4pp cuts in the corporate income tax and in the firms’ social security contribution rates, and a 5pp reduction in the highest personal income tax rate. These cuts would be financed by combating tax evasion, curbing wasteful public expenditure and, if necessary, by increasing the VAT rate by up to 2pp. Using a dynamic general equilibrium model to evaluate the effects of this tax shock, we find that the long- term GDP gains would be between 0.72% and 2.91% while the effects on lifetime private welfare would range between –0.99% and 0.9%. The efficiency of this tax reform package depends critically on the way the tax cuts are financed to ensure deficit neutrality. Because investment is subject to adjustment costs, to alleviate the long-run trade-off between GDP and welfare, tax policy changes must induce a significant increase in net labor income.info:eu-repo/semantics/publishedVersio

Measurement of glass transition in native wheat flour by dynamic mechanical thermal analysis (DMTA)

This work describes a method to study glass transition on native starch powders, based on dynamical mechanical thermal analysis using compression tests, and was applied to wheat flour (13.5% water content). This method will allow the determination of Tg in native (unprocessed) starchy materials, with minimal disturbance of the natural structures. The influence of the test conditions (heating rate, frequency and strain) on the glass transition measurements was determined using factorial designs. The values of Tg determined as the maxima of the energy dissipation (peaks in E ) of native flour and of freezedried pre-gelatinized flour were not statistically different (around 64 C). The heating rate did not affect the measurements in the range tested (0.25 to 1 C min 1). An interactive effect of the strain amplitude and the frequency was detected. The significance of this interaction can be caused by differences in mechanical energy dissipation, which would indicate that not only temperature but also the total energy input may affect this transition. Slight effects of phase separation between gluten and starch were found on native flour

Bandwidth and memory efficiency in real-time ray tracing

Real time ray tracing has been given a lot of attention in recent years in the academic and research community. Several novel algorithms have appeared that parallelize different aspects of the ray tracing algorithm through the use of a GPU. Among these, the creation of Bounding Volume Hierarchies (BVHs). We believe that recent approaches have failed to consider the performance impact of memory accesses in GPU and how their cost affects the overall performance of the application. In this work we show that by reducing memory bandwidth and footprint we are able to achieve significant improvements in BVH traversal times. We do this by compressing the BVH and the triangle mesh in a parallel manner after its creation, in each frame, and then decompressing it as needed while traversing the BVH

Comportamento a acções perpendiculares ao plano, de alvenaria de enchimento com dano prévio

Com a entrada em fase de obrigatoriedade dos Eurocódigos surgem novos requisitos que têm de ser cumpridos pelos edifícios, ou pelas suas partes. É o caso da exigência de garantia de estabilidade de painéis de alvenaria não estrutural, à acção sísmica perpendicular ao plano, em edifícios com sistema estrutural de betão armado. Este documento apresenta a campanha de ensaios realizada na Universidade do Minho, com vista à caracterização do comportamento de elementos deste tipo a estas acções, quando danificados previamente por acções no plano. Para o efeito o esquema de ensaio proposto é composto por duas fases. Na primeira o painel é sujeito, de forma cíclica e gradual, a um nível de deslocamento de referência no plano. Na segunda é sujeito a uma acção cíclica, uniforme e perpendicular ao plano. Serão testadas e comparadas quatro soluções construtivas distintas, nomeadamente: parede simples não reforçada, parede dupla não reforçada, parede simples com reforço em junta horizontal e parede simples com reforço em malha de aço. De acordo com o desenvolvimento dos trabalhos, serão apresentados os resultados de uma parede simples