996 resultados para Zolo, Danilo


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Poulty house typology and the materials used (mainly for roofing) are the determining factors for an appropriate thermal condition aiming at production. In this context, the main point of this paper was to identify differences in the internal environment of two poultry houses, using monitoring and afterwards using statistics for comparing the environmental variables. The data analyzed did not show evidence of better thermal comfort for the house which was covered with ceramic roofing tile, because this house did not have ridged vents, making the hot air exit from the house difficult by the chimney effect. The ammonia concentration measured inside both houses was within the comfort limit. The temperature and humidity index of the house covered with ceramic roofing tiles was higher than the house which was covered with cement asbestos roofing tile, even though lower temperature on the tiles' surfaces was verified, showing the positive effects of the use of ridge vents at the housing. Based on the results obtained it is recommended for the Bastos, SP region, that poulty houses should be built with the ridge vent and long eaves beyond the roof of ceramic tiles.

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Considering different single and multiphase circuits feeding linear and non-linear loads, this paper presents theoretical discussions and experimental evaluation of the recent Conservative Power Theory (CPT), by means of Virtual Instrumentation concepts. The main goal is to analyze the results of such power theory definitions under nonsinusoidal and unbalanced conditions, pointing out its major advantages, possible drawbacks or relevant aspects for discussion. © 2009 IEEE.

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To address daily fluctuations in electricity demands, the quantities of water passing through the turbines of hydropower plants can vary significantly (up to fourfold) during a 24-h cycle. This study evaluates the effects of hourly variations in water discharges on the limnological conditions observed in two below-dam river stretches. The study reservoirs, Capivara and Taquaruçu, are the 9th and 10th reservoirs in a cascade of dams in the Paranapanema River in south-east Brazil. The reservoirs exhibit different trophic conditions, water retention times, thermal regimes and spillway positions. Capivara Reservoir is deeper, meso-eutrophic, with a high water retention time and hypolimnetic discharges (32 m) varying between 500 and 1400 m3 s-1. In contrast, Taquaruçu Reservoir is relatively shallow, oligo-mesotrophic, and has a low retention time, with water discharges varying between 500 and 2000 m3 s-1. Its turbine water intake zone also is more superficial (7 m). For two periods of the year, winter and summer, profiles of limnological measurements were developed in the lacustrine (above-dam site) zones of the reservoirs, as well as in the downstream river stretches (below-dam site). In both cases, the sampling was carried out at 4-h intervals over a complete nictemeral cycle. The results demonstrated that the reservoir operating regime (water discharge variations) promoted significant differences in the conditions of the river below the dams, especially for water velocity, turbidity, and nutrient and suspended solids concentrations. The reservoir physical characteristics, including depth, thermal stratification and outlet structure, are also key factors influencing the limnology and water quality at the below-dam sampling sites. In the case of Capivara Reservoir, for example, the low dissolved oxygen concentration (<5.0 mg L-1) in its bottom water layer was transferred to the downstream river stretches during the summer. These study results demonstrated that it is important to continue such investigations as a means of verifying whether or not these high-amplitude/low-frequency variations could negatively affect the downstream river biota. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Asia Pty Ltd.

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Among the several variables that influence timber harvesting is the slope, which influences the productivity of forest machines. In this experiment the harvester was evaluated technically and economically while cutting and processing eucalyptus activity on different slope classes. The technical analysis included a study of time and movements by the method of continuous time; productivity was determined by the volume in cubic meters of wood processing. The economic analysis included the parameters of operational cost, production cost and energy consumption. The analysis of the data showed that productivity decreased according to the increase of the percent slope inclination, resulting in an effective work hour productivity increase from 18.72 to 39.71 m 3sc, with a mean of operating cost of US$ 78.78 per work hour.

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One of the critical problems in implementing an intelligent grinding process is the automatic detection of workpiece surface burn. This work uses fuzzy logic as a tool to classify and predict burn levels in the grinding process. Based on acoustic emission signals, cutting power, and the mean-value deviance (MVD), linguistic rules were established for the various burn situations (slight, intermediate, severe) by applying fuzzy logic using the Matlab Toolbox. Three practical fuzzy system models were developed. The first model with two inputs resulted only in a simple analysis process. The second and third models have an additional MVD statistic input, associating information and precision. These two models differ from each other in terms of the rule base developed. The three developed models presented valid responses, proving effective, accurate, reliable and easy to use for the determination of ground workpiece burn. In this analysis, fuzzy logic translates the operator's human experience associated with powerful computational methods.

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Considering the Conservative Power Theory (CPT), this paper proposes some novel compensation strategies for shunt passive or active devices. The CPT current decompositions result in several current terms, which are associated with specific physical phenomena (average power consumption P, energy storage Q, load and source distortion D, unbalances N). These current components were used in this work for the definition of different current compensators, which can be selective in terms of minimizing particular disturbing effects. Compensation strategies for single and three-phase four-wire circuits have also been considered. Simulation results have been demonstrated in order to validate the possibilities and performance of the proposed strategies. © 2010 IEEE.

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Proton radiation therapy is a precise form of radiation therapy, but the avoidance of damage to critical normal tissues and the prevention of geographical tumor misses require accurate knowledge of the dose delivered to the patient and the verification of his position demand a precise imaging technique. In proton therapy facilities, the X-ray Computed Tomography (xCT) is the preferred technique for the planning treatment of patients. This situation has been changing nowadays with the development of proton accelerators for health care and the increase in the number of treated patients. In fact, protons could be more efficient than xCT for this task. One essential difficulty in pCT image reconstruction systems came from the scattering of the protons inside the target due to the numerous small-angle deflections by nuclear Coulomb fields. The purpose of this study is the comparison of an analytical formulation for the determination of beam lateral deflection, based on Molière's theory and Rutherford scattering with Monte Carlo calculations by SRIM 2008 and MCNPX codes. © 2010 American Institute of Physics.

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Cryptographic systems are safe. However, the management of cryptographic keys of these systems is a tough task. They are usually protected by the use of password-based authentication mechanisms, which is a weak link on conventional cryptographic systems, as the passwords can be easily copied or stolen. The usage of a biometric approach for releasing the keys is an alternative to the password-based mechanisms. But just like passwords, we need mechanisms to keep the biometrical signal safe. One approach for such mechanism is to use biometrical key cryptography. The cryptographic systems based on the use of biometric characteristics as keys are called biometrical cryptographic systems. This article presents the implementation of Fuzzy Vault, a biometrical cryptographic system written in Java, along with its performance evaluation. Fuzzy Vault was tested on a real application using smartcards.

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This study proposal was to evaluate the changes at a masticatory muscle temporalis and masseter, through a eletromyographic, at ponters of the right unilateral bite posterior, verifying the difference at the eletric activity between right and left sides. Twenty female volunteers, with ages between 7 and 8 (x = 7.4). The eletromyographics signals were collected in both sides in all volunteers in rest situations and in an usual isotonic mastication, right, left and bilateral and the maximun isometric constriction, which sinal was used to the eletric activity amplitude normalization. The results signed that the right masseter muscle presents an expressive statistic difference, if compared with the left masseter muscle during the left and right mastication, suggesting a right unilateral mastication. The muscle haven't gotten any expressive variance in this amplitude which remained to a proximate flat noticed in a right and habitual mastication, suggesting a right and one sided mastication during the left mastication occurs a raise of the eletric signal amplitude of the muscle left masseter. The right masseter muscle haven't gained any expressive variance, which remained in a proximate flat observed in an usual and right mastication, suggesting a muscular pattern hyperfunction next to the dental crossing.

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In this work, a Hydrogen Nuclear Magnetic Resonance (1H NMR) method has been developed to determine aromatics and ethanol in Brazilian commercial gasoline with low olefin content. The proposed method involves subdividing an 1H NMR spectrum into regions, each of which is assumed to be associated with a specific type of structural group (OH, CH, CH2 and CH3). The method is based on the assignment of overlapping regions of 1H NMR spectra due to the signals of naphthene (N), iso and normal paraffins (P) and ethanol (E). Each 1H NMR spectrum was divided into 8 regions and the integration was correlated to the percentage of the substances to be determined. The results of the analysis by 1H NMR were compared with analysis of GC-FID obtained with the PONA system. The proposed technique of 1H NMR was shown to be an appropriate method for this sample type.

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In this article, we present the notion of symbolic behavior in accordance with neuropsychopathology research from the first decades of the past century, carried out particularly in the context of aphasia research. The guiding axis was the presence of this notion in the first work by Merleau-Ponty, The structure of behavior. Based on research by Gelb and Goldstein, the philosopher takes ownership of the semantics of the symbolic and characterizes human corporality based on its capacity to move beyond the immediate nature of the experienced situations. We also show that the circumscription of symbolic behavior was conditioned by theoretical-methodological changes that permitted the passage from localizationist conceptions to globalist attitudes in view of pathological events of cerebral origin.

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Forest species with hard seeds often pose considerable problems to nursery managers because their hard and impermeable seed coats hinder and delay germination. Therefore, this work aimed to determine the most efficient, practical and low cost methodology to overcome dormancy in Sesbania virgata (Cav.) Pers. Seed, a specie with potential for recovery of degraded areas. The seeds were submitted to chemical scarification by immersion in sulfuric acid during a period of 5, 10, 20 and 30 minutes, mechanical scarification and heat treatment. After the scarification the seeds were submitted to germ test in germination chambers at 25oC and photoperiod of 14 h. Treatment with mechanical scarification showed the highest germination percentage (98%), followed by chemical scarification for 30 minutes (57%). The heat treatment in spite of obtaining a higher germination percentage than the controls had abnormal development of seedlings and is not therefore recommended for seeds of S. virgata. From the parameters utilized in this study, we recommend the use of the mechanical scarification to overcome dormancy of S. virgata seeds.

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Fossil fuels such as diesel are being gradually replaced by biodiesel, a renewable energy source, cheaper and less polluting. However, little is known about the toxic effects of this new energy source on aquatic organisms. Thus, we evaluated biochemical biomarkers related to oxidative stress in Nile tilapia (Oreochromis niloticus) after two and seven exposure days to diesel and pure biodiesel (B100) and blends B5 and B20 at concentrations of 0.01 and 0.1mLL -1. The hepatic ethoxyresorufin-O-deethylase activity was highly induced in all groups, except for those animals exposed to B100. There was an increase in lipid peroxidation in liver and gills in the group exposed to the higher concentration of B5. All treatments caused a significant increase in the levels of 1-hydroxypyrene excreted in the bile after 2 and 7d, except for those fish exposed to B100. The hepatic glutathione-S-transferase increased after 7d in animals exposed to the higher concentration of diesel and in the gill of fish exposed to the higher concentration of pure diesel and B5, but decreased for the two tested concentrations of B100. Superoxide dismutase, catalase and glutathione peroxidase also presented significant changes according to the treatments for all groups, including B100. Biodiesel B20 in the conditions tested had fewer adverse effects than diesel and B5 for the Nile tilapia, and can be suggested as a less harmful fuel in substitution to diesel. However, even B100 could activate biochemical responses in fish, at the experimental conditions tested, indicating that this fuel can also represent a risk to the aquatic biota. © 2011 Elsevier Ltd.