Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-09-13T11:28:35Z No. of bitstreams: 1 ROSINALDO DO RIO MEDEIROS - TESE (PPGEP) 2009.doc: 40662016 bytes, checksum: 19de7f51f29e605072615b107e5da0c9 (MD5) / Made available in DSpace on 2018-09-13T11:28:35Z (GMT). No. of bitstreams: 1 ROSINALDO DO RIO MEDEIROS - TESE (PPGEP) 2009.doc: 40662016 bytes, checksum: 19de7f51f29e605072615b107e5da0c9 (MD5) Previous issue date: 2009-12-17 / Capes / A expansão por umidade (EPU) consiste na expansão sofrida por alguns materiais cerâmicos quando em contato com água na forma líquida ou de vapor. O processo de EPU quando desenvolvido em blocos cerâmicos pode acarretar o aparecimento de trincas em alvenarias ou mesmo danos estruturais mais severos. Nos últimos anos, os estudos desenvolvidos sobre EPU e resistência mecânica, estão centrados em materiais para revestimentos cerâmicos, com poucos dados relativos ao comportamento mecânico de blocos cerâmicos sujeitos à EPU. Neste contexto, este trabalho objetiva estudar a influência do teor de quartzo na EPU e no comportamento mecânico de massas cerâmicas para uso em blocos furados. Para tanto, foram analisadas amostras de massas usadas na fabricação de blocos cerâmicos, oriundas de Parelhas-RN. À argila plástica foi adicionado quartzo nos teores de 10, 20 e 30%. Os corpos de prova, moldados por extrusão, queimados nas temperaturas de 850, 900 e 950º C, foram submetidos ao ensaio de aceleração de EPU por autoclavagem com pressão de 0,7 MPa por 5 h e resistência mecânica à flexão com carregamento em três pontos. A EPU foi determinada por dilatometria a 600oC. Os resultados indicam que a adição de quartzo finamente moído, nos teores especificados e nas condições estudadas, de uma forma geral, pouco influenciou nos resultados de EPU, exceto para a adição de 30%, e que a adição de quartzo fino em proporções mais elevadas reduz o comportamento mecânico dos blocos cerâmicos. / The Moisture Expansion (EPU) is the expansion experienced by some ceramic materials when in contact with water in liquid or vapor. The process developed EPU when bricks can cause the appearance of cracks in masonry or even more severe structural damage. In recent years, studies done on EPU and mechanical strength, focus on materials for ceramic tiles, with few data on the mechanical behavior of ceramic blocks subject to the EPU. In this context, this work aims at studying the influence of quartz content in the EPU and the mechanical behavior of ceramic bodies for use in blocks bored. To that end, samples were analyzed mass used in the manufacture of ceramic bricks, coming from Parelhas-RN. In plastic clay was added in the quartz contents of 10, 20 and 30%. The samples, cast extrusion, burned at temperatures of 850, 900 and 950 ° C, were tested on accelerating EPU by autoclaving at a pressure of 0.7 MPa for 5 h and flexural loading with three points. The EPU was determined by dilatometry to 600 °C. The results indicate that the addition of finely ground quartz, the levels specified under the conditions studied, in general, had little influence on the results of public schools and that the addition of fine quartz in higher rates reduces the mechanical behavior of ceramic blocks.

Följande examensarbete fokuserar på frågan kring hur eleverna ska inkluderas i planering och genomförande av skolarbetet. Vi har valt att undersöka elevdemokrati i skolan generellt och i svenskämnet i synnerhet och belyser både rektors, lärares och elevernas perspektiv. Syftet är att diskutera hur skolans demokratiska uppdrag och arbetsformer framträder i svenskämnet. Vi vill veta hur elevinflytandet i svenskämnet ser ut i praktiken och jämföra detta med redan befintlig forskning. Utifrån detta vill vi se om det finns ett behov av elevplanerad undervisning, EPU (Se definition, kap 1.2) och vilka eventuella attityder som kan finnas gentemot denna typ av arbetsmodell. När vi skriver och intervjuar utgår vi från åk 7–9 och den svenska grundskolans läroplan och skollag.Även om vår idé och arbetsmodell enligt oss, med fördel kan appliceras i alla ämnen har vi valt att avgränsa vårt arbete till vårt förstaämne, svenskämnet. Resultat av intervjuerna visar på positiva attityder till en modell som EPU men lärarna och rektor menar att faktorer som ålder och mognad är avgörande gällande mängden delaktighet. Svenskämnet har genom våra undersökningar och tidigare forskning visat sig vara ett ämne där demokratifrågor med fördel kan appliceras, detta på grund av ämnets bredd och förmågor, det vill säga läsa, skriva, och tala som är grundläggande för att bidra till aktivt deltagande i en demokrati. Däremot visar våra undersökningar att svenskämnets innehåll sällan präglas av medbestämmande och elevinflytande gällande till exempel planering.Nyckelord: Elevdemokrati, Elevinflytande, EPU, Elevplanerad undervisning, Svenskämnet, Svenskämnet som demokratiämne

This thesis examines whether the level of Swedish economic policy uncertainty (EPU) can predict excess returns on the Swedish stock market. We run out-of-sample forecasting using an EPU-based predictive model constructed with the official Swedish EPU index developed by Armelius et al. (2017). Forecasting errors for one-, two-, three-, six-, and twelve-month holding periods and four measures of central tendency are analysed and compared against a random walk benchmark. The findings suggest that EPU has limited forecasting ability for excess stock returns in Sweden, and the EPU-based model demonstrates superior forecasting accuracy only in two out of twenty instances, both for the one-month holding period. However, the forecast errors remain relatively large, casting doubt on the model's ability to outperform the market. Furthermore, the EPU-based model consistently underestimates excess returns, questioning its usefulness as a predictor. Notably, the random walk benchmark's forecast error improves with longer holding periods, raising doubts about the predictability of market movements in the long term.

Electro-hydrostatic Actuation Systems (EAS) successfully combine the advantages of electro-mechanical actuation - such as high-energy efficiency and low noise emission - with the benefits of electro-hydraulic technology –which include robustness and the precise handling of large forces. This paper defines keywords like EAS and Electro-hydraulic pump unit (EPU), and provides a comparison of the two technologies. Given the wide range of EAS technology topics, it is only possible to briefly introduce and discuss these in this paper. This technology has reached a level that renders it a strong mechanism for machine manufacturers to support existing and future motion control requirements.

Este estudio explora los efectos de la incertidumbre económica política (EPU) en la inversión, medido como la formación bruta de capital fijo, usando datos trimestrales para el periodo 2016-2019 para 5 países de Latinoamérica: Brasil, Chile, Colombia, México y Perú. Primero, se construye el indicador de incertidumbre basado en la contabilización de artículos periodísticos y en la metodología del EPU para los países objetivos a partir de la base de datos GDELT GKG disponible en Google Big Query. Luego, se aplica un modelo de vectores autorregresivos panel (PVAR) estimado por el método generalizado de momentos (GMM). Ante choques en la tasa de crecimiento del EPU se encuentra un impacto negativo y significativo sobre la tasa de crecimiento de la inversión después de un trimestre. Adicionalmente, se encuentra que este choque se va corrigiendo hasta disiparse por completo después de 5 trimestres. Los resultados también sugieren que la tasa de crecimiento de la inversión se ve afectada por la tasa de crecimiento del PBI del periodo anterior, la tasa de crecimiento del tipo de cambio real, la inflación y los cambios en la presión tributaria. / This study explores the effects of economic policy uncertainty (EPU) on investment, measured as gross fixed capital formation, using quarterly data for the period 2016-2019 for 5 Latin American countries: Brazil, Chile, Colombia, Mexico and Peru. First, the uncertainty indicator based on the accounting of newspaper articles and the EPU methodology is constructed for the target countries from the GDELT GKG database available in Google Big Query. Then, a panel autoregressive vector model (PVAR) estimated by the generalized method of moments (GMM) is applied. In the face of shocks to the EPU growth rate there is a significant negative impact on the investment growth rate after one quarter. In addition, it is found that this shock is corrected until it dissipates completely after five quarters. The results also suggest that the investment growth rate is affected by the GDP growth rate of the previous period, the real exchange rate growth rate, inflation and changes in the tax burden. / Trabajo de investigación

1 Abstract We study economic policy uncertainty spillovers on a panel of ten countries between April 1998 to September 2019. The analysis is performed on the Economic Policy Uncertainty indices data. To measure the spillovers, we utilize forecast error variance decompositions of VAR model. We found that approximately half of the forecast variance can be explained by spillovers shocks across countries. Further, we disentangle the spillover measure to short-, mid- and long-term cycles using frequency domain. Our results suggest that most of the spillovers are caused by shocks into low frequencies, hence with long persistence. Employing quantile regression on equation-by-equation basis to estimate the VAR model, we find that idiosyncratic uncertainty shocks do not propagate strongly at the median but that powerful spillovers occur in the right tail of distribution. Additionally, we perform rolling window estimates of the spillovers. The results indicate strong variation in time, especially during major geopolitical events, such as Iraq War (2003), Global Financial Crisis (2007-09), European debt crisis (2010-12) or Brexit (2016).