494 resultados para Relógio D’Água


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This work shows a study about the Generalized Predictive Controllers with Restrictions and their implementation in physical plants. Three types of restrictions will be discussed: restrictions in the variation rate of the signal control, restrictions in the amplitude of the signal control and restrictions in the amplitude of the Out signal (plant response). At the predictive control, the control law is obtained by the minimization of an objective function. To consider the restrictions, this minimization of the objective function is done by the use of a method to solve optimizing problems with restrictions. The chosen method was the Rosen Algorithm (based on the Gradient-projection). The physical plants in this study are two didactical systems of water level control. The first order one (a simple tank) and another of second order, which is formed by two tanks connected in cascade. The codes are implemented in C++ language and the communication with the system to be done through using a data acquisition panel offered by the system producer

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The State of Rio Grande do Norte, Brazil, possess major deposits of feldspar, clay, kaolin and talc, all raw materials used in the production of porcelainized stoneware tiles. Conversely, state industries manufacture only low added value red ceramics. Porcelainized stoneware tiles is one of the noblest ceramics, depicting low water absorption (typically below of 0,5%), in addition to excellent staining resistance and mechanical strength. The present work aims at investigating the potential of local raw materials for the production of porcelainized stoneware tiles. To that end, these materials were characterized by X-ray fluorescence, X-ray diffraction, particle size analysis, thermal gravimetric analysis and thermal differential analysis. Admixtures containing different compositions were prepared and fired at three temperatures, 1150, 1200 and 1250°C for 30 min. After firing, tests samples were characterized by water absorption tests, linear retraction, dilatometric analysis, apparent porosity, apparent specific mass, flexural strength, and microstructural analysis by XRD and SEM. The results revealed that ceramics with porcelainized stoneware tiles characteristics could be produced from raw materials originated in the State of Rio Grande do Norte

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The oil industry, experiencing a great economic and environmental impact, has increasingly invested in researches aiming a more satisfactory treatment of its largest effluent, i.e., produced water. These are mostly discarded at sea, without reuse and after a basic treatment. Such effluent contains a range of organic compounds with high toxicity and are difficult to remove, such as polycyclic aromatic hydrocarbons, salts, heavy metals, etc.. The main objective of this work was to study the solar distillation of produced water pre-treated to remove salts and other contaminants trough of a hybrid system with a pre-heater. This developed apparatus was called solar system, which consists of a solar heater and a conventional distillation solar still. The first device consisted of a water tank, a solar flat plate collector and a thermal reservoir. The solar distillator is of simple effect, with 1m2 of flat area and 20° of inclination. This dissertation was divided in five steps: measurements in the solar system, i.e. temperatures and distillate flow rate and weather data; modeling and simulation of the system; study of vapor-liquid equilibrium of the synthetic wastewater by the aqueous solution of p-xylene; physical and chemical analyses of samples of the feed, distillate and residue, as well as climatology pertinent variables of Natal-RN. The solar system was tested separately, with the supply water, aqueous NaCl and synthetic oil produced water. Temperature measurements were taken every minute of the thermal reservoir, water tank and distillator (liquid and vapor phases). Data of solar radiation and rainfall were obtained from INPE (National Institute for Space Research). The solar pre-heater demonstrated to be effective for the liquid systems tested. The reservoir fluid had an average temperature of 58°C, which enabled the feed to be pre-heated in the distillator. The temperature profile in the solar distillator showed a similar behavior to daily solar radiation, with temperatures near 70°C. The distillation had an average yield of 2.4 L /day, i.e., an efficiency of 27.2%. Mathematical modeling aided the identification of the most important variables and parameters in the solar system. The study of the vapor-liquid equilibrium from Total Organic Carbon (TOC) analysis indicated heteroazeotropia and the vapor phase resulted more concentrated in p-xylene. The physical-chemical analysis of pH, conductivity, Total Dissolved Solids (TDS), chlorides, cations (including heavy metals) and anions, the effluent distillate showed satisfactory results, which presents a potential for reuse. The climatological study indicates the region of Natal-RN as favorable to the operation of solar systems, but the use of auxiliary heating during periods of higher rainfall and cloud cover is also recommended

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The Pitimbu River Basin is concern reason, therefore this is one of the mains freshwater sources for the Natal city supplying. The Pitimbu waters river flow into Jiqui pond, as the main supplier of this, that supplies 16% of Natal population and there is a bigger importance despite the supplying of a parcel of Natal city made joining underground waters with the water proceeding from the Jiqui pond, being used for dilution waters of contaminated wells with nitrate. Even with the importance of the Pitimbu, there is a strong pressure of occupation of its edge according to a critical urban growth, becoming the situation worse and increasing the necessity of management of the use and occupation of the ground and keeping the control of the prompt pollution, as punctual as diffuse. There are many studies about Pitimbu River Basin, however they summarize themselves to some months or even in a few years. This work, that gathers these information, increasing the amplitude and making possible an evaluation of the attitude of the water in a period extended for an evaluation of values of variable quality of water referring to the standards, that usually happens about the variable frequency distribution, central tendency and measures of dispersion, as the coefficient of variation, coefficient of skewness and the coefficient of determination of certain variable on another one. This work to evaluates the quality conditions of the Pitimbu river waters by analyzing thirty five (35) variables Physical, chemical and biological in eight (8) points of water course since 1993 to 2007. Given this situation, all knowledge about the waters quality conditions obtained in this work, is a strong subsidy for management of use and ground occupation, considering the river basin as territorial unit of management, and as the water is public good domain, being a priority human use, It is necessary to guarantee to current and the future generations available water resources in appropriate standards of quality as the established standard and identifying possible reasons of pollution through statistics analysis

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The potentially toxic cyanobacterial blooms in water bodies are spread across the globe, resulting in the loss of water quality and adverse effects on human health. In arid and semiarid regions, the hydrologic regime characterized by an annual cycle of drought and rain, change the volume and the retention time of the reservoir. Such changes affect the limnological characteristics and causing changes in composition and biomass community of cyanobacteria. The reservoir Cruzeta (Zmax = 8.7 m) is a eutrophic water supply source located in the semiarid tropical (Northeast Brazil). Raised the hypothesis that the hydrological regime of semi-arid tropical is a determining factor in the availability of resources in eutrophic water sources, which influences the composition of dominant species of cyanobacteria. The aim of this study was to analyze the changes in biomass and species composition of cyanobacteria for two annual hydrological cycles and evaluate factors drivers. The study was divided into five distinct periods (dry 2010, rain 2011, dry 2011, rain 2012, dry 2012). The dominant group found in all periods was Cyanobacteria (99% of total biomass), which contributed to the low diversity. The filamentous species Cylindrospermopsis raciborskii was present at both points in almost every study. The colonial species Microcystis panniformis and Sphaerocavum brasiliensis dominated only in periods with lower volumes of water. The diatoms contribute more to the biomass during the period of severe drought. The point near the dam (P1) had phytoplankton biomass larger than the point near the tributary (P2). The dominant species of colonial cyanobacteria lasted until the overflow in P1, and P2 this dominance was until the first rains. The redundancy analysis indicated that physical factors such as light availability and water level were the main factors driving the seasonal succession of phytoplankton. The composition of phytoplankton in spring was alternated by species of filamentous cyanobacteria in conditions of poor stability of the water column, such as Cylindrospermopsis raciborskii, and colonial species under conditions of high stability of the water column, such as Microcystis panniformis and Sphaerocavum brasiliensis. The extremes of torrential rains and severe droughts, governed by the hydrological regime of the semi-arid region led to the availability of resources in the watershed, directing the spatial and temporal dynamics of phytoplankton in the reservoir Cruzeta

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Poucos são os estudos que possibilitam verificar quais as respostas fisiológicas são associadas ao desempenho em uma amostra de ciclistas de elite nacional. Portanto, o objetivo do presente estudo foi determinar e relacionar diferentes índices fisiológicos aeróbios com o desempenho em testes contra relógio de 4 e 20km em ciclistas de alto nível. A amostra foi composta por 14 ciclistas profissionais de elite nacional do sexo masculino (28,5 ± 4,7 anos, 73,47 ± 8,29 kg, 176 ± 6,76 cm), que realizaram um teste progressivo em laboratório para a determinação do consumo máximo de oxigênio (VO2max: 62,23 ± 8,28 ml·kg·min-1), intensidade relativa ao VO2max (iVO2max: 500,83 ± 58,65 w), economia de movimento (EM: 0,1166 ± 0,0362 ml·kg·min·w-1) e 1º e 2º limiares ventilatórios (LV1: 348,21 ± 43,26 w; LV2: 417,86 ± 60,79 w, respectivamente). Também foram submetidos a duas provas de 4 e 20km contra relógio. Para correlação entre os índices fisiológicos e desempenho, foi utilizado o coeficiente de correlação de Pearson (p< 0,05). Não foi encontrada correlação entre os índices fisiológicos (VO2max absoluto e relativo, iVO2max, EM, LV1 e LV2) e o desempenho de 4km (r= 0.38; 0.16; -0.33; 0.20; -0.50; -0.20, respectivamente) e 20km (r= 0.24; 0.01; -0.13; -0.12; -0.48; -0.19, respectivamente) contra relógio em atletas de alto nível. Estes resultados sugerem que tais variáveis não apresentam capacidade de explicar o desempenho em provas de contra relógio nas respectivas distâncias, provavelmente, devido à homogeneidade entre os sujeitos.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region

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The circadian behavior associated with the 24 hours light-dark (LD) cycle (T24) is due to a circadian clock , which in mammals is located in the hypothalamic suprachiasmatic nucleus (SCN). Under experimental conditions in which rats are espoused to a symmetric LD 22h cycle (T22) the two SCN regions, ventrolateral (vl) and dorsomedial (dm), can be functionally isolated, suggesting that each region regulates distinct physiological and behavioral components. The vl region regulates the locomotor activity and slow wave sleep (SWS) rhythms, while the dm region assures the body temperature and paradoxical sleep (PS) rhythms regulation. This research aimed to deepen the knowledge on the functional properties of circadian rhythmicity, specifically about the internal desynchronization process, and its consequences to locomotor activity and body temperature rhythms as well as to the sleep-wake cycle pattern in rats. We applied infrared motion sensors, implanted body temperature sensors and a telemetry system to record electrocorticogram (ECoG) and electromyogram (EMG) in two rat groups. The control group under 24h period LD cycle (T24: 12hL-12hD) to the baseline record and the experimental group under 22h period LD cycle (T22: 11hL- 11hD), in which is known to occur the uncoupling process of the circadian locomotor activity rhythm where the animals show two distinct locomotor activity rhythms: one synchronized to the external LD cycle, and another expressed in free running course, with period greater than 24h. As a result of 22h cycles, characteristic locomotor activity moment appear, that are coincidence moments (T22C) and non coincidence moments (T22NC) which were the main focus or our study. Our results show an increase in locomotor activity, especially in coincidence moments, and the inversion of locomotor activity, body temperature, and sleep-wake cycle patterns in non coincidence moments. We can also observe the increase in SWS and decrease in PS, both in coincidence and non coincidence moments. Probably the increases in locomotor activity as a way to promote the coupling between circadian oscillators generate an increased homeostatic pressure and thus increase SWS, promoting the decreasing in PS

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This study focuses on the potential of several techniques used to identify depositional geometries and paleogeographical investigation on the SW border of the Potiguar Basin. Three areas were selected for an integrated geological, geophysical and geochemistry study. The main used techniques were facies analysis, remote sensing,ground penetrating radar (GPR) and gamma-ray in outcrops, as well as petrographic microscope observations and the using of scanning eletronic microscopic (SEM), and Carbon and Oxygen Isotopic study in the carbonate tufa. These methodological approaches were very efficient in the facies analysis of 2D geometries. The GPR profiles carried out in Quixeré identified important geological reflectors which allowed to the identification of depositional geometries of tufa. However, GPR profiles were not able to identify geological reflectors in the Apodi and Olho d´Água da Bica outcrops. Gammaray profiles also presented good results, which justify their use in 1D and 2D geometric analysis. Carbon and Oxygen Isotopic analyses were also used to investigate paleoenvironmental setting of tufa deposits. It is important to remark the excellent resultsof GRP using in the identification of deposition al geometries of tufa and their contact relationships with the underlying rocks. Field analysis of faults indicate a vertical sigma-1 orientation which was associated to normal faults

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Este trabalho teve como objetivo principal analisar as mudanças ocorridas no clima local onde o município de Apodi/RN está inserido, em virtude da construção da Barragem Santa Cruz do Apodi. Foram utilizadas para o tratamento dos dados climáticos precipitação pluviométrica, umidade relativa do ar e temperatura técnicas estatísticas como Desvio Padrão, Teste T, Coeficiente de Variação e Média aritmética, além do modelo matemático. Para o balanço hídrico foi aplicado o método de Thornthwait (1948), considerando dois períodos em análise: o anterior e posterior a construção da Barragem Santa Cruz do Apodi, respectivamente 1995 e 2005. os resultados obtidos permitiram inferir que a hipótese inicial levantada se confirma, ou seja, a construção da Barragem Santa Cruz do Apodi, está influenciando diretamente numa alteração no que concerne à condição atmosférica local, especialmente no parâmetro umidade relativa do ar. Quanto ao balanço hídrico, observou-se a predominância do déficit hídrico especialmente entre os meses de junho a janeiro, período de estiagem; um excedente ocorrente entre os meses de maio e junho, conseqüente do período chuvoso; e uma reposição hídrica antecedendo e sucedendo este período, chuvoso, ou seja, compreendendo os meses de fevereiro a junho. Todas as considerações e análises poderão contribuir para o planejamento de abastecimento d´água, a irrigação, auxílio na previsão de enchentes e estiagens, bem como o manejo do uso da água subterrânea

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Running water is one of the most important of all the physical processes which fashion the landscape, allowing gravity to operate along the valley floors. Besides this, the streams show a fast adjustment to the crustal deformations, even to the most gentle ones. This geologic behavior turns them a potential tool for neotectonic studies, specially the analysis of morphotnetric parameters associated with hydraulic gradient and discharge, this second factor being directly proportional to the extension of the streams. Both elements, gradient and stream length, can be combined in the SL index. The purpose of this paper is to show the RDE index application in the neotectonics analysis of the Rio do Peixe hydrographic basin and to compare the obtained values with the geologic basement incised by the streams. This basement encompasses Cretaceous sedimentary rocks of post-Serra Oeral Formation magmatism (Caiuá and Bauru groups) and Quaternary deposits that include chiefly recent alluvial plains and some Pleistocene terrace deposits. In the final part of this paper, an attempt is made in order to correlate the RDE results and the neotectonic framework admitted to this portion of the São Paulo State territory, as well as with field geologic, seismologic and paleoseismologic known elements. The results indicate the presence of two groups of anomalies: The first set corresponds to the Marília-Exaporã Plateau border, and the second one, located in the central portion of the hydrographic basin, is correlated to the Presidente Prudente seimogenic zone.

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The inadequate land use in the low course of the river Acaraú is speeding up processes of erosion in some degrees. This process is accented in the areas where caatinga was removed for implantation of pastures and agriculture. Concomitantly, the plain of flooding of the river Acaraú an accumulation of sand with the carry of these sediments, resulting in the widening of the fluvial plain and reduction of the shape water, with increase of the evapotranspiration and consequence salinization, proceeding from the local substratum. This paper aimed at the crossing of diverse space information (geomorfology, soil, declivity, geology and land use) in environment SIG, for determination of the susceptible areas to the erosion and an accumulation of sand in the low course of the Acaraú river, north of the State of the Ceará, Brazil. The results allow to evaluate the application of this tool in the planning and management of the environment, from the crossing of the type of use with the used environment and the consequent impact to the ecosystem.