Análise das flutuações econômicas no Brasil, de 1991 a 2008, a partir dos modelos RBC

Fluctuation Economic research grow up from 80’s with the Dynamic Stochastic General Equilibrium Models (DSGE), where the agent are search for the optimum point at the intertemporal decisions, that is decision over time of how consumers make choice between present and future consumption at the uncertain environment. The real business cycles (RBC) are example this kind of DSGE models. The objectives of the paper are understands the theoretical structure of the RBC model and compare it with the Brazilian economy. The economic real showed that consumption and investment are pro-cyclic and the investment is more volatile than the consumption, the real wage and paid hours were pro-cyclic, where this second variable was more volatile. The artificial economic was the Hansen benchmark real business cycle model with indivisible labor and the stochastic neoclassical growth model. Between the real and artificial economic, the variable interest was more different, that direction was anticyclic and pro-cyclic respectively. The RBC model with parameters of the economic Brazilian date, the adherence better, when looking to relative volatile in product relationship.Real business cycles, Aggregate fluctuations, Brazil, Research Methods/ Statistical Methods,

Análises de ciclos econômicos no Brasil (1980-2009)

As sequências de expansões e contrações da atividade econômica são conhecidas como ciclos econômicos e afetam todos os agentes econômicos. O método de modelar o crescimento econômico e suas flutuações pode ser feito a partir de um modelo de tendência estacionária (TS) ou a partir de um processo de diferença estacionária (DS). Neste artigo foi utilizado o primeiro método, para o período de 1980 a 2009, onde o período de maior expansão foi verificado a partir de junho de 2003 cuja duração foi de 56 meses. Quando analisado o co-movimento das séries, para verificar a sua direção com relação à atividade econômica, os resultados obtidos foram os esperados, o que se destacou foi o movimento anti-cíclico da taxa de juros e da taxa de cambio

Photocatalytic Treatment Techniques using Titanium Dioxide Nanoparticles for Antibiotic Removal from Water

The increasing of emerging micropollutants presence in drinking water sources has brought new challenges to existing water treatment systems (WTS), highlighting the need of innovative and low-cost technological solutions. Recent advances in nanotechnology enable highly efficient and multifunctional processes, providing sustainable alternatives to current water treatment practices. This chapter presents the results of several pilot-scale studies developed to assess the effects of TiO2 nanoparticles on antibiotic removal efficiency, using different low-cost photocatalytic reactors. The characterization of its photo-oxidation kinetics also performed considering different test scenarios in order to assess the effects of the major abiotic parameters on oxytetracycline (OTC) removal efficiency, which achieved the maximum values of 96% and 98% using the photocatalysis with TiO2 and the photocatalytic filtration, respectively. It must be highlighted the surprising regeneration ability showed by the photocatalytic porous medium, developed at a lab-scale, which can completely recover its oxidative properties after few hours of simple sun exposure

Durabilidade de argamassas com baixo consumo de cimento em face ao ataque por sulfato de s?dio

Al?m dos avan?os para a sociedade, a ind?stria do cimento ? marcada por uma s?rie de quest?es ambientais. Neste sentido, tendo em vista os impactos gerados pela produ??o e consumo de cimento, surge a necessidade de solu??es tecnol?gicas que visem a mitiga??o desses danos. Este trabalho tem como objetivo detalhar o comportamento de corpos de prova prism?ticos, 4x4x16 cm, frente ao ataque por sulfato de s?dio. Foram estudadas tr?s composi??es: argamassa com 100% de cimento, argamassa com substitui??o de 60% do cimento por RTM, e esta ?ltima com adi??o de 5% de cal hidratada. Os corpos de prova foram moldados a partir da dosagem do concreto de refer?ncia com o tra?o definido. Para realiza??o do ensaio de expans?o geom?trica, fez-se uso do concreto na fase de argamassa, a qual n?o possui agregado gra?do. Os corpos de prova foram postos nas duas curas (cal e sulfato de s?dio) logo ap?s a desmoldagem. O principal fen?meno observado ap?s a imers?o foi, como j? citado, a expans?o geom?trica, que ? o aumento das dimens?es das argamassas. As pe?as com RTM e cal apresentaram maiores expans?es no ambiente com sulfato de s?dio, devido ao alto teor de alumina no res?duo, com expans?es acima do limite para um material resistente ? sulfatos

As fontes da determinação da escolaridade dos trabalhadores da indústria de transformação brasileira

In this article, we analyze the swings sources of demand for labor force, according to the level of schooling, in the Brazilian manufacturing industry, in the 1994-2008 period of time. We consider two theories to explain these swings sources: the Heckscher-Ohlin Theorem (H-O) and the ability bias hypothesis. In the empirical analysis, we make use of decomposition analysis to verify which one of them best fits the data employed. The results of the empirical analysis give little support to the ability bias hypothesis when we utilize higher education labor force. Additionally, we find out that the international trade forces emphasized by the H-O Theorem are relevant in the Brazilian economy. However, it was verified that the increase of intermediate level of education labor force supply was the main cause of schooling increase in the manufacturing industry labor force.manufacturing industry; Heckscher-Ohlin Theorem; ability bias hypothesis; labor force qualification

Fatores de Oferta e Demanda na Qualificação dos Trabalhadores Brasileiros

In the present article, we attempt to identify the sources of the changes in the labor schooling level in the three main sectors of the Brazilian economy: manufacturing, services and agriculture; based on the theoretical perspective of the three sectors hypothesis. It was verified that, despite the changes in the product and employment among sectors, mainly in the 90s, the relative demands for qualified workers has not experimented significant changes. Moreover, in the periods in which schooling has increased more, the workers’ wage has decreased more. This fact suggests that the increase in labor qualification was mainly due to the increase of this factor supply. The structural changes had contributed, in general, in a marginal and negative way to labor force level of qualification demand in all the three sectors.labor schooling; structural changes; demand for qualified labor; supply of qualified labor.