Desempenho de um painel fotovoltaico de baixa tensão, acoplado ao protótipo de um conversor dc/dc topologia Booster

Low voltage solar panels increase the reliability of solar panels due to reduction of in series associations the configurations of photovoltaic cells. The low voltage generation requires DCDC converters devices with high efficiency, enabling raise and regulate the output voltage. This study analyzes the performance of a photovoltaic panel of Solarex, MSX model 77, configured to generate an open circuit voltage of 10.5 V, with load voltage of 8.5 V, with short circuit current of 9 A and a power of 77 W. The solar panel was assembled in the isolated photovoltaic system configuration, with and without energy storage as an interface with a DCDC converter, Booster topology. The converter was designed and fabricated using SMD (Surface Mounted Devices) technology IC (integrated circuit) that regulates its output voltage at 14.2 V, with an efficiency of 87% and providing the load a maximum power of 20.88 W. The system was installed and instrumented for measurement and acquisition of the following data: luminosities, average global radiation (data of INPE Instituto Nacional de Pesquisas Espaciais), solar panel and environment temperatures, solar panel and DC-DC converter output voltages, panel, inverter, and battery charge output currents. The photovoltaic system was initially tested in the laboratory (simulating its functioning in ideal conditions of operation) and then subjected to testing in real field conditions. The panel inclination angle was set at 5.5°, consistent with the latitude of Natal city. Factors such as climatic conditions (simultaneous variations of temperature, solar luminosities and ra diation on the panel), values of load resistance, lower limit of the maximum power required by the load (20.88 W) were predominant factors that panel does not operate with energy efficiency levels greater than 5 to 6%. The average converter efficiency designed in the field test reached 95%

Reutilização de imóveis de interesse patrimonial, voltados para a ahabitação: um estudo de caso na Ribeira-Natal/RN

This work analyzes the reutilization of real estate of patrimonial interest, come back toward habitation. One understands as real estate of patrimonial interest the old ones that present relevant architectural typologies that must be preserved; some buildings that represent characteristic architectural styles of a determined period; some valued real estates for the history of the city (historical, memory and image signification that has of certain places) and buildings with exceptional artistic elements. In short, real estate of patrimonial interest. The place or site to be studied will be the neighborhood of the Ribeira, because is an area that protects a bigger interest for the historic patrimony of the city. The habitation use was thought as a booster element of revitalization processes of degradable historic site, contributing to the preservation of artistic, architectural and historic patrimony, and thus to stimulate the accomplishment of the re-qualification of the neighborhood of the Ribeira. It is intended with the present study to examine alternatives to make possible habitation re (uses) in the historical quarter of the Ribeira in old constructions of patrimonial value

A participação popular na elaboração de políticas públicas de desenvolvimento local: um estudo no Município de Serrinha/RN (1997-2004)

The question of participation has been debated in Brazil since the 1980 decade in search a better way to take care of poulation s demand. More specificaly after the democratic open (1985) begins to be thought ways to make population participates of decisions related to alocation of public resources. The characteristic of participates actualy doesn t exist, population to be carried through is, at top, consulted, and the fact population participates stays restrict to some technics interests at the projects, mainly of public politics of local development. Observe that this implementation happens through a process and that has its limits (pass) that could be surpassed through strategies made to that. This dissertation shows results of a research about participative practices in city of Serrinha between 1997 and 2004, showing through a study of the case of Serrinha what was the process used to carry through these pratices in a moment and local considered model of this application. The analyses were developed through a model of research elaborated by the author based on large literature respects the ideal process to implant a participative public politics. The present research had a qualitative boarding, being explorative and descritive nature. The researcher (author of this dissertation) carried through all the research phases, including the transcriptions of interviews that were recorded with a digital voice recorder. Before the analysis of these data was verified that despite the public manager (former-mayor) had had a real interest in implant a process of local development in city, he was not able to forsee the correct process to do it. Two high faults were made. The first was the intention to have as tool a development plan, what locked up to make this plan was the booster of supossed participative pratice and no the ideal model that would be a plan generate by popular initiative. The second one was absence of a critical education project for the population that should be the fisrt step to carry through a politc like that

Fabricação de eco-composito com a fibra de lã canina

The Sustainability has been evidence in the world today; organizations have sought to be more and more into this philosophy in their processes, whether products or attendance. In the present work were manufactured eco-composites with animal fiber (dog wool) that is currently discarded into the environment without any use. The fibers were characterized and made matting (non-woven). The phases of the project were consisted to develop methods and to convert these fibers (booster) blended with polyester resin (matrix) in different proportions (10%, 20% and 30%) at the composite. Were studied fiber characteristics, mechanical properties of the composites, water absorption and scanning electron microscopy. Initially, the fibers were treated with solution of sodium hydroxide of 0.05 mols, and then taken to matting preparing at the textile engineering laboratory - UFRN. The composites were made by compression molding, using an orthophthalic polyester resin as matrix and 1% MEK (methyl ethyl ketone peroxide) as initiator (catalyst). To evaluate the mechanical tests (tensile and flexural) and water absorption were made twelve specimens with dimensions 150x25x3 mm were cut randomly. According to the standard method, tensile tests (ASTM 3039) bending tests (ASTM D790) were performed at the mechanical testing of metals at laboratory UFRN. The results of these tests showed that the composite reinforced with 30% had a better behavior when exposed to tension charge; while on the three points bending test showed that the composite reinforced with 10% had a better behavior. In the water absorption test it was possible to see that the highest absorption happened on the composite reinforced with 30%. In the micrographs, it was possible to see the regions of rupture and behavior of the composite (booster / matrix)

Reutilização de imóveis de interesse patrimonial, voltados para a ahabitação: um estudo de caso na Ribeira-Natal/RN

This work analyzes the reutilization of real estate of patrimonial interest, come back toward habitation. One understands as real estate of patrimonial interest the old ones that present relevant architectural typologies that must be preserved; some buildings that represent characteristic architectural styles of a determined period; some valued real estates for the history of the city (historical, memory and image signification that has of certain places) and buildings with exceptional artistic elements. In short, real estate of patrimonial interest. The place or site to be studied will be the neighborhood of the Ribeira, because is an area that protects a bigger interest for the historic patrimony of the city. The habitation use was thought as a booster element of revitalization processes of degradable historic site, contributing to the preservation of artistic, architectural and historic patrimony, and thus to stimulate the accomplishment of the re-qualification of the neighborhood of the Ribeira. It is intended with the present study to examine alternatives to make possible habitation re (uses) in the historical quarter of the Ribeira in old constructions of patrimonial value