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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Solar energy for domestic use in southern Brazil

Hedenberg, Ola, Wallander, John January 2008 (has links)
<p>Almost all the domestic water in Brazil is heated with an electrical heater directly by the end consumer. A typical heater has an effect of 5 400 W and when the whole population takes a shower in the evening it causes big peaks in the electrical grid. This consumption peaks could be reduced by simple and cheap solar collector system. </p><p>Different system technologies and the most important parts of a solar collector system are described in the technical background. In Lajeado almost every system is a self-circulated system because of the simplicity and the lower costs. </p><p>Solar cooling as an alternative to the vapor compressor chillers has been studied. The cooling demand is biggest when the sun shines; this makes the sun perfect as a source to cooling. The ab- and adsorption chillers as a method in the future have been discussed in this paper; however it has only been studied briefly because small scale chillers using the technology can not be found on the market yet. </p><p>A number of different systems have been dimensioned after the existing conditions of Lajeado, the town where the project has been carried out in. Prizes and costs for both installation and materials come from the local solar collector supplier. With this as a background; several systems for various hot water demands has been dimensioned and costs and repayment time been calculated. A study of all the systems shows that, if the hot water demand increases and the systems get bigger, the profitability grows and the repayment time becomes shorter, down to three years. In almost every case the repayment time was under eight years, which makes solar heating attractive and the profit is good for the southern Brazil.</p>
132

Wind power in Brazil

Elin, Karlsson January 2009 (has links)
<p>As welfare and industry production gets higher the demand for electricity increases. Almost 90 % of the electricity generated in Brazil is from renewable sources, 85 % of the renewable energy comes from hydropower. Even if Latin America has a lot of potential for wind power their installed capacity in only 1 % of the worlds total installed capacity. Lately more and more wind turbines and wind farms are appearing along Brazil’s over 7500 kilometer long coastline.</p><p>Osorio wind farm is the largest wind farm in Latin America with a total installed effect of 150 MW. In the same state, Rio Grande du Sul, a farmer has shown interest for using his property for wind power. The purpose of this project is to lay the foundation for a deeper investigation about using Aguapé farm’s property for wind power and to show the future possibilities for Brazilian wind power.</p><p>The study is made on set in Brazil, divided into two parts, one theoretical research part and one practical part with a field trip to Aguapé farm.</p><p>In 2002 The Brazilian Government launched the PROINFA program, Alternative Sources for Energy Incentive. This year, 2009, the first wind power projects auctions are held to increase the generation from renewable electricity sources. Wind power in Brazil has the highest production when the level in the hydropower dams are at the lowest, which by integrating the electrical generating wiht wind power makes it possible to save water and avoiding lack of electricity.</p><p>Aguapé farm is located between one of the worlds biggest fresh water lakes, Lagao dos Patos, and the Atlantic Ocean. The location has very good wind potential, almost like offshore because of the closeness to large areas of water. Road connections to the farm are functional in good and dry weather conditions and not far away a 138kV power line passes through. </p><p>Surrounding neighbors are positive to wind power which makes it easier with problem caused by wind turbines, for example noise. About 40 kilometers from the farm Lagoa do Peixe National Park is located. Suggestion from the Aguapé owner is to stop with the rice production, which is disturbing the park’s natural hydrological system, to use the property for wind turbines instead.</p><p>Conclusions of the study shows that the potential for wind power at Aguapé farm is excellent and that wind power at Aguapé farm will help both the owner, Lagoa do Peixe National Park and Brazil to a better future.</p>
133

Frequency response function analysis of the equatorial margin of Brazil using gravity and bathymetry

Macario, Ana L. G. 28 July 1989 (has links)
The overall objective of this study is to address questions concerning the long-term mechanical strength of the lithosphere across the equatorial margin of Brazil. The approach used in this study consists of calculating the frequency response function estimates, also called admittance, using gravity and bathymetry data. These experimental estimates are then compared to theoretical admittance curves for Airy and thin elastic plate models for which estimates on the flexural rigidity or, equivalently, effective elastic thickness may be made. Twelve profiles, each 256 km long, were extracted from gridded gravity and bathymetry data (data sources: project EQUANT, Defense Mapping Agency, National Geophysical Data Center files and GEOS 3/SEASAT altimeter data). Three profiles were specifically used for testing truncation errors introduced by four different data treatment procedures (before Fourier transforming the data) : detrending, applying 10% cosine tapering, mirror imaging and the use of the first derivatives. The method I adopted is similar to the one used by McNutt (1983) and consists of testing how reliably a given admittance estimate can be recovered as a function of the data treatment procedure. A "predicted" gravity anomaly was obtained by convolving each bathymetric profile with a theoretical admittance filter. The edges of this anomaly are then submitted to the same treatment as the corresponding bathymetric profile before Fourier transforming both profiles and calculating admittance. The stability of the long-wavelength admittance estimates, in the presence of noise, was also investigated by introducing Gaussian noise, in the range of -50 to +50 mGals, in the "predicted" gravity signal. The results indicate that relatively unbiased long-wavelength admittance estimates can be obtained by using the first derivative of the data sets. In addition, it is shown that the mirroring technique, used in previous admittance studies across Atlantic-type margins, leads to overestimated admittance values and, therefore, overestimated flexural rigidities. Neither the theoretical curves for the Airy model nor the plate flexure model can explain the experimental admittance estimates. Not only are the experimental admittance estimates higher than the predicted values but they also have a narrower peak than the theoretical curves. This raises the question of the applicability of highly simplified isostatic models for tectonic provinces such as Atlantic-type continental margins. The following reasons may explain the discrepancies between the experimental and theoretical admittance estimates: (1) The abrupt nature of the transition between oceanic and continental crust controlled by the Romanche Fracture Zone - Unlike the eastern North American continental margin which was formed as a result of extensive rifling and pulling apart, the obliquely-rifled equatorial margin of Brazil has undergone a complex tectonic evolutionary process, where additional components such as shear and right-lateral wrenching were present. Therefore, representing the margin as a thin homogeneous elastic plate might be reasonable when the transition is gradual (for which the uniform flexural rigidity assumption seems reasonable) but is probably not a good approximation when it is as abrupt as the equatorial margin of Brazil (2) Presence of subsurface loads - Previous studies have shown that estimates of the average flexural rigidity of continental lithosphere using the admittance approach are biased when subsurface loads are present. In principle, the proximity of the Romanche Fracture Zone and associated volcanism suggest that shallow buried loads, caused by intrusive bodies, might be present in the area. This could partially account for the mismatch between theoretical curves and experimental admittance estimates. (3) "Masked" estimates - The admittance estimates presented here are likely to reflect the combination of two different signals: one related to the compensation of the Barreirinhas/Piaui-Camocim sub-basin which has no topographic/bathymetric expression and the other one related to the topography/bathymetry and its compensation which is of interest in the admittance studies. Since the wavelengths of these signals do not differ by much (around 80-100 km for the basin) it is possible that in the averaging process some overlapping occurs. The combination of these signals could yield anomalous results masking the admittance estimates in the diagnostic waveband. In addition, I present a two-dimensional cross section obtained by forward modelling the gravity anomaly along a profile using the line integral method. The uniform sedimentary infill of the Barreirinhas/Piaui-Camocim basin is enough to account for the gravity low over the inner shelf and no Moho topography is required. A plausible explanation for this "rootless" basin structure is that the lithosphere is capable of supporting the sediment infill load, and thus, has finite flexural rigidity (basin is locally uncompensated). / Graduation date: 1990
134

Isostatic evolution and crustal structures of the Amazon continental margin determined by admittance analyses and inversion of gravity data

Braga, Luiz F. S. 06 June 1991 (has links)
Graduation date: 1992
135

The Effect of Changes in Maternity Leave Policy on Labor Market Outcomes for Females in Brazil

Bastos de Malafaia, Viviane Maria 04 March 2009 (has links)
Maternity leave policy has changed a few times over the last 20 years in Brazil. This dissertation investigates how a ceiling imposed on the maternity leave benefit paid by Brazilian Social Security in Dec, 1998 and its temporary suspension in May, 1999 affected females' employment and earnings using difference-in-difference method. We apply the difference-in-difference method to examine whether the changes in maternity leave policy negatively affected females in the labor market. Our analysis uses four treatment groups: 1) young females, aged 20 to 40 years; 2) young females working in the private sector; 3) older females, aged 41 to 65 years, working in the private sector; and 4) young females with infants. Young females were selected based on the fact that they have a higher probability of giving birth compared to older females and, consequently, using the maternity leave benefit. The second and third groups were supposedly the groups directly reached by these changes in maternity leave policy since earnings and employment in the public sector should not be based on an individual's gender and therefore discrimination may be absent or less prevalent there than in the private sector. We also include young females with infants as a treatment group since employers may use this information to infer the probability of a female having another child. We also propose four control groups: 1) older females aged between 41 and 65 years; 2) young females working in the public sector; 3) older females working in the public sector; and 4) young males. Overall, our results show that the limit imposed on maternity leave benefits paid by Social Security and the transfer of the responsibility of paying the remaining wages to employers negatively affected females' hourly wages, and this negative effect seems to have persisted even while the limit was temporarily suspended. Furthermore, young females were more affected by the change in policy than older females. These results lead us to think that these changes in maternity leave policy may have slowed the convergence of females' wages toward males' wages or "forced" females to swim upstream during the period from May 1999 to March 2003.
136

Wind power in Brazil

Elin, Karlsson January 2009 (has links)
As welfare and industry production gets higher the demand for electricity increases. Almost 90 % of the electricity generated in Brazil is from renewable sources, 85 % of the renewable energy comes from hydropower. Even if Latin America has a lot of potential for wind power their installed capacity in only 1 % of the worlds total installed capacity. Lately more and more wind turbines and wind farms are appearing along Brazil’s over 7500 kilometer long coastline. Osorio wind farm is the largest wind farm in Latin America with a total installed effect of 150 MW. In the same state, Rio Grande du Sul, a farmer has shown interest for using his property for wind power. The purpose of this project is to lay the foundation for a deeper investigation about using Aguapé farm’s property for wind power and to show the future possibilities for Brazilian wind power. The study is made on set in Brazil, divided into two parts, one theoretical research part and one practical part with a field trip to Aguapé farm. In 2002 The Brazilian Government launched the PROINFA program, Alternative Sources for Energy Incentive. This year, 2009, the first wind power projects auctions are held to increase the generation from renewable electricity sources. Wind power in Brazil has the highest production when the level in the hydropower dams are at the lowest, which by integrating the electrical generating wiht wind power makes it possible to save water and avoiding lack of electricity. Aguapé farm is located between one of the worlds biggest fresh water lakes, Lagao dos Patos, and the Atlantic Ocean. The location has very good wind potential, almost like offshore because of the closeness to large areas of water. Road connections to the farm are functional in good and dry weather conditions and not far away a 138kV power line passes through. Surrounding neighbors are positive to wind power which makes it easier with problem caused by wind turbines, for example noise. About 40 kilometers from the farm Lagoa do Peixe National Park is located. Suggestion from the Aguapé owner is to stop with the rice production, which is disturbing the park’s natural hydrological system, to use the property for wind turbines instead. Conclusions of the study shows that the potential for wind power at Aguapé farm is excellent and that wind power at Aguapé farm will help both the owner, Lagoa do Peixe National Park and Brazil to a better future.
137

A Comprehensive Study of Issues Affecting Poverty and Inequality in Brazil

DeClue, Deona Tenae 12 July 2007 (has links)
Brazil is a country that is considered an anomaly among many economist and political scientist because of its unique social, political and economic structure. Due to this fact, many of the rules that apply when analyzing developing countries do not necessarily apply to Brazil. For this reason, in the following chapters this paper will seek to dissect several distinctive issues that affect poverty and inequality in Brazil. Particularly, I have gathered information from various academic and data sources to provide a comprehensive picture of the true socio-economic situation in Brazil.
138

Brazil's elevated interest rates a case of irrational pessimism or guarded optimism? /

Johnson, Ed. January 2006 (has links)
Thesis (M.A.)--University of Florida, 2006. / Title from title page of source document. Document formatted into pages; contains 98 pages. Includes vita. Includes bibliographical references.
139

Sterilization for votes in the Brazilian northeast : the case of Pernambuco /

Caetano, André Junqueira, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 287-296). Available also in a digital version from Dissertation Abstracts.
140

Ethnographies of identity : (re)constructing race and gender in contemporary Brazil /

Caldwell, Kia Lilly, January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 291-307).

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