979 resultados para fundamental parameters
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Numerical modelling is a valuable tool for simulating the fundamental processes that take place during a heating. The models presented in this paper have enabled a quantitative assessment of the effects of initial pile temperature, pile size and mass and coal particle size on the development of a heating. All of these parameters have a certain criticality in the coal self-heating process.
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Along with other diseases that can affect binocular vision, reducing the visual quality of a subject, Congenital Nystagmus (CN) is of peculiar interest. CN is an ocular-motor disorder characterized by involuntary, conjugated ocular oscillations and, while identified more than forty years ago, its pathogenesis is still under investigation. This kind of nystagmus is termed congenital (or infantile) since it could be present at birth or it can arise in the first months of life. The majority of CN patients show a considerable decrease of their visual acuity: image fixation on the retina is disturbed by nystagmus continuous oscillations, mainly horizontal. However, the image of a given target can still be stable during short periods in which eye velocity slows down while the target image is placed onto the fovea (called foveation intervals). To quantify the extent of nystagmus, eye movement recordings are routinely employed, allowing physicians to extract and analyze nystagmus main features such as waveform shape, amplitude and frequency. Use of eye movement recording, opportunely processed, allows computing "estimated visual acuity" predictors, which are analytical functions that estimate expected visual acuity using signal features such as foveation time and foveation position variability. Hence, it is fundamental to develop robust and accurate methods to measure both those parameters in order to obtain reliable values from the predictors. In this chapter the current methods to record eye movements in subjects with congenital nystagmus will be discussed and the present techniques to accurately compute foveation time and eye position will be presented. This study aims to disclose new methodologies in congenital nystagmus eye movements analysis, in order to identify nystagmus cycles and to evaluate foveation time, reducing the influence of repositioning saccades and data noise on the critical parameters of the estimation functions. Use of those functions extends the information acquired with typical visual acuity measurement (e.g., Landolt C test) and could be a support for treatment planning or therapy monitoring. © 2010 by Nova Science Publishers, Inc. All rights reserved.
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Why students of 6th year still present oral marks in written? To answer this question our paper presents what they are and how writing and grammatical deviations occur and emerged in an attempt to expand on these studies. The same objective to evaluate the presence of these deviations in genres produced by students of the 6th year of the Municipal School Manoel Catarino Filho and check if there are more variation deviations or grammatical deviations. It also aims to improve the linguistic and discursive ability of students in various traffic environments of certain genres and consequently the formation of active readers and writers. In order to better understand how this process occurs, the text starts of the socio discursive conception of gender, with the theoretical background studies of Bakhtin (1992) and Marcuschi (2002) about this conception and the rhetoric conception of Aristoteles and Platão. The text underlies even the works of Callou (2007), Neves (2003), Faraco (2002), Franchi (2006) and Cagliari (2005) on the Grammar School, linguistic variation as also on the sociolinguistic parameters as well in research on the phonetics and phonology of Oliveira e Nascimento (1990), Seara (2009), Hora (2009) and in the PCN. To compose the corpus of this study we collected 23 texts produced by students to serve as a data source for analysis of the presented deviations by quantitative and qualitative research method, in which categorize the deviations found in two groups: oral and linguistic variation deviations and writing and grammar deviations. The results showed that there was a rate of occurrence of oral and variation deviations greater of writing and grammar deviations. We concluded that the orality has a great influence on the written production of students. Finally, we propose some activities aimed at minimizing the occurrence of deviations in written productions of the students.
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We present the results of electrical resistivity, magnetic susceptibility, specific heat and x-ray absorption spectroscopy measurements in Tb1−xYxRhIn5 (x = 0.00, 0.15, 0.4.0, 0.50 e 0.70) single crystals. Tb1−xYxRhIn5 is an antiferromagnetic AFM compound with ordering temperature TN ≈ 46 K, the higher TN within the RRhIn5 serie (R : rare earth). We evaluate the physical properties evolution and the supression of the AFM state considering doping and Crystalline Electric Field (CEF) effects on magnetic exchange interaction between Tb3+ magnetic ions. CEF acts like a perturbation potential, breaking the (2J + 1) multiplet s degeneracy. Also, we studied linear-polarization-dependent soft x-ray absorption at Tb M4 and M5 edges to validate X-ray Absorption Spectroscopy as a complementary technique in determining the rare earth CEF ground state. Samples were grown by the indium excess flux and the experimental data (magnetic susceptibility and specific heat) were adjusted with a mean field model that takes account magnetic exchange interaction between first neighbors and CEF effects. XAS experiments were carried on Total Electron Yield mode at Laborat´onio Nacional de Luz S´ıncrotron, Campinas. We measured X-ray absorption at Tb M4,5 edges with incident polarized X-ray beam parallel and perpendicular to c-axis (E || c e E ⊥ c). The mean field model simulates the mean behavior of the whole system and, due to many independent parameters, gives a non unique CEF scheme. XAS is site- and elemental- specific technique and gained the scientific community s attention as complementary technique in determining CEF ground state in rare earth based compounds. In this work we wil discuss the non conclusive results of XAS technique in TbRhIn5 compounds.
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Wheat (Triticum aestivum L.) has a long tradition as a raw material for the production of malt and beer. While breeding and cultivation efforts for barley have been highly successful in creating agronomically and brew- technical optimal specialty cultivars that have become well established as brewing barley varieties, the picture is completely different for brewing wheat. An increasing wheat beer demand results in a rising amount of raw material. Wheat has been - and still is – grown almost exclusively for the baking industry. It is this high demand that defines most of the wheat breeding objectives; and these objectives are generally not favourable in brewing industry. It is of major interest to screen wheat varieties for brewing processability and to give more focus to wheat as a brewing cereal. To obtain fast and reliable predications about the suitability of wheat cultivars a new mathematical method was developed in this work. The method allows a selection based on generally accepted quality characteristics. As selection criteria the parameters raw protein, soluble nitrogen, Kolbach index, extract and viscosity were chosen. During a triannual cultivation series, wheat varieties were evaluated on their suitability for brewing as well as stability to environmental conditions. To gain a fundamental understanding of the complex malting process, microstructural changes were evaluated and visualized by confocal laser scanning and scanning electron microscopy. Furthermore, changes observed in the micrographs were verified and endorsed by metabolic changes using established malt attributes. The degradation and formation of proteins during malting is essential for the final beer quality. To visualise fundamental protein changes taking place during malting, samples of each single process step were analysed and fractioned according their solubility. Protein fractions were analysed using a Lab-on-a-chip technique as well as OFFgel analysis. In general, a different protein distribution of wheat compared to barley or oat could be confirmed. During the malting process a degradation of proteins to small peptides and amino acids could be observed in all four Osborn fractions. Furthermore, in this study a protein profiling was performed to evaluate changes during the mashing process as well as the influence of grist composition. Differences in specific protein peaks and profile were detected for all samples during mashing. This study investigated the suitability of wheat for malting and brewing industry and closed the scientifical gap of amylolytic, cytolytic and proteolytic changes during malting and mashing.
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Acompanha: Material paradidático em educação ambiental para o 6º ano do ensino fundamental
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In this paper, by using the method of separation of variables, we obtain eigenfunctions and fundamental solutions for the three parameter fractional Laplace operator defined via fractional Caputo derivatives. The solutions are expressed using the Mittag-Leffler function and we show some graphical representations for some parameters. A family of fundamental solutions of the corresponding fractional Dirac operator is also obtained. Particular cases are considered in both cases.
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Os Parâmetros Curriculares Nacionais (PCNs) em História para os terceiro e quarto ciclos do ensino fundamental (atualmente anos finais), publicados pelo Governo Federal em 1998, traçaram as diretrizes e orientações específicas para esta área de ensino, dentro do novo contexto educacional consolidado pela Lei de Diretrizes e Bases da Educação Nacional de 1996 (LDBEN/96), refletido por sua vez pelo novo período de redemocratização constitucional iniciado em 1988 e em curso até os dias de hoje. Compreender a visão social de mundo preconizada no documento, com suas potencialidades (ou não) para o ensino de História em nosso País, através da análise dos aspectos historiográficos e educacionais que o formam, representa o objetivo central desta pesquisa, procurando – se identificar também os interesses e valores dos grupos sociais e culturais nele traduzidos. Dentro de uma perspectiva crítico-dialética, os referidos PCNs e suas implicações com as questões acima expostas só poderão ser investigadas em uma dimensão contextualizada com a sociedade brasileira contemporânea.
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Background: Long-term exposure to infrasound and low frequency noise (ILFN <500 Hz, including infrasound) can lead to the development of vibroacoustic disease (VAD). VAD is a systemic pathology characterized by the abnormal growth of extracellular matrices in the absence of inflammatory processes, namely of collagen and elastin, both of which are abundant in the basement membrane zone of the vocal folds. ILFN-exposed workers include pilots, cabin crewmembers, restaurant workers, ship machinists and, in previous studies, even though they did not present vocal symptoms, ILFN-exposed workers had significant different voice acoustic patterns (perturbation and temporal measures) when compared with normative population. Study Aims: The present study investigates the effects of age and years of occupational ILFN-exposure on voice acoustic parameters of 37 cabin crewmembers: 12 males and 25 females. Specifically, the goals of this study are to: 1) Verify if acoustic parameters change over the age and years of ILFN-exposure and 2) Determine if there is any interaction between age and years of ILFNexposure on voice acoustic parameters of crewmembers. Materials and Methods: Spoken phonatory tasks were recorded with a C420III PP AKG head-worn microphone and a DA-P1 Tascam DAT. Acoustic analyses were performed using KayPENTAX Computer Speech Lab and Multi-Dimensional Voice Program. Acoustic parameters included speaking fundamental frequency, perturbation measures (jitter, shimmer and harmonicto- noise ratio), temporal measures (maximum phonation time and s/z ratio) and voice tremor frequency. Results: One-way ANOVA analysis revealed that as the number of ILFN-exposure years increased male cabin crewmembers presented significant different shimmer values of /i/ as well as tremor frequency of /u/. Females presented significantly different jitter % of /i, a, O/ (p <0.05). Lastly, Two-way ANOVA analysis revealed that for females, there was a significant interaction between age and occupational ILFN-exposure for voice acoustic parameters, namely for jitter’s mean for /a, O/ and shimmer’s (%) mean for /a, i/ (p <0.05). Discussion and Conclusion: These perturbation measure patterns may be indicative of histological changes within the vocal folds as a result of ILFN-exposure. The results of this study suggest that voice acoustic analysis may be an important tool for confirming ILFN-induced health effects.
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The main purpose of this study is to assess the relationship between four bioclimatic indices for cattle (environmental stress, heat load, modified heat load, and respiratory rate predictor indices) and three main milk components (fat, protein, and milk yield) considering uncertainty. The climate parameters used to calculate the climate indices were taken from the NASA-Modern Era Retrospective-Analysis for Research and Applications (NASA-MERRA) reanalysis from 2002 to 2010. Cow milk data were considered for the same period from April to September when the cows use the natural pasture. The study is based on a linear regression analysis using correlations as a summarizing diagnostic. Bootstrapping is used to represent uncertainty information in the confidence intervals. The main results identify an interesting relationship between the milk compounds and climate indices under all climate conditions. During spring, there are reasonably high correlations between the fat and protein concentrations vs. the climate indices, whereas there are insignificant dependencies between the milk yield and climate indices. During summer, the correlation between the fat and protein concentrations with the climate indices decreased in comparison with the spring results, whereas the correlation for the milk yield increased. This methodology is suggested for studies investigating the impacts of climate variability/change on food and agriculture using short term data considering uncertainty.
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The paper states an introduction, description and implementation of a PV cell under the variation of parameters. Analysis and observation of a different parameters variation of a PV cell are discussed here. To obtain the model for the purpose of analyzing an equivalent circuit with the consisting parameters a photo current source, a series resistor, a shunt resistor and a diode is used. The fundamental equation of PV cell is used to study the model and to analyze and best fit observation data. The model can be used in measuring and understanding the behaviour of photovoltaic cells for certain changes in PV cell parameters. A numerical method is used to analyze the parameters sensitivity of the model to achieve the expected result and to understand the deviation of changes in different parameters situation at various conditions respectively. The ideal parameters are used to study the models behaviour. It is also compared the behaviour of current-voltage and power-voltage by comparing with produced maximum power point though it is a challenge to optimize the output with real time simulation. The whole working process is also discussed and an experimental work is also done to get the closure and insight about the produced model and to decide upon the validity of the discussed model.
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In this paper it is proposed to obtain enhanced and more efficient parameters model from generalized five parameters (single diode) model of PV cells. The paper also introduces, describes and implements a seven parameter model for photovoltaic cell (PV cell) which includes two internal parameters and five external parameters. To obtain the model the mathematical equations and an equivalent circuit consisting of a photo generated current source, a series resistor, a shunt resistor and a diode is used. The fundamental equation of PV cell is used to analyse and best fit the observation data. Especially bisection iteration method is used to obtain the expected result and to understand the deviation of changes in different parameters situation at various conditions respectively. The produced model can be used of measuring and understanding the actions of photovoltaic cells for certain changes and parameters extraction. The effect is also studied with I-V and P-V characteristics of PV cells though it is a challenge to optimize the output with real time simulation. The working procedure is also discussed and an experiment presented to get the closure and insight about the produced model and to decide upon the model validity. At the end, we observed that the result of the simulation is very close to the produced model.