716 resultados para Taxação ótima


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Cloud computing can be defined as a distributed computational model by through resources (hardware, storage, development platforms and communication) are shared, as paid services accessible with minimal management effort and interaction. A great benefit of this model is to enable the use of various providers (e.g a multi-cloud architecture) to compose a set of services in order to obtain an optimal configuration for performance and cost. However, the multi-cloud use is precluded by the problem of cloud lock-in. The cloud lock-in is the dependency between an application and a cloud platform. It is commonly addressed by three strategies: (i) use of intermediate layer that stands to consumers of cloud services and the provider, (ii) use of standardized interfaces to access the cloud, or (iii) use of models with open specifications. This paper outlines an approach to evaluate these strategies. This approach was performed and it was found that despite the advances made by these strategies, none of them actually solves the problem of lock-in cloud. In this sense, this work proposes the use of Semantic Web to avoid cloud lock-in, where RDF models are used to specify the features of a cloud, which are managed by SPARQL queries. In this direction, this work: (i) presents an evaluation model that quantifies the problem of cloud lock-in, (ii) evaluates the cloud lock-in from three multi-cloud solutions and three cloud platforms, (iii) proposes using RDF and SPARQL on management of cloud resources, (iv) presents the cloud Query Manager (CQM), an SPARQL server that implements the proposal, and (v) comparing three multi-cloud solutions in relation to CQM on the response time and the effectiveness in the resolution of cloud lock-in.

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The modern industrial progress has been contaminating water with phenolic compounds. These are toxic and carcinogenic substances and it is essential to reduce its concentration in water to a tolerable one, determined by CONAMA, in order to protect the living organisms. In this context, this work focuses on the treatment and characterization of catalysts derived from the bio-coal, by-product of biomass pyrolysis (avelós and wood dust) as well as its evaluation in the phenol photocatalytic degradation reaction. Assays were carried out in a slurry bed reactor, which enables instantaneous measurements of temperature, pH and dissolved oxygen. The experiments were performed in the following operating conditions: temperature of 50 °C, oxygen flow equals to 410 mL min-1 , volume of reagent solution equals to 3.2 L, 400 W UV lamp, at 1 atm pressure, with a 2 hours run. The parameters evaluated were the pH (3.0, 6.9 and 10.7), initial concentration of commercial phenol (250, 500 and 1000 ppm), catalyst concentration (0, 1, 2, and 3 g L-1 ), nature of the catalyst (activated avelós carbon washed with dichloromethane, CAADCM, and CMADCM, activated dust wood carbon washed with dichloromethane). The results of XRF, XRD and BET confirmed the presence of iron and potassium in satisfactory amounts to the CAADCM catalyst and on a reduced amount to CMADCM catalyst, and also the surface area increase of the materials after a chemical and physical activation. The phenol degradation curves indicate that pH has a significant effect on the phenol conversion, showing better results for lowers pH. The optimum concentration of catalyst is observed equals to 1 g L-1 , and the increase of the initial phenol concentration exerts a negative influence in the reaction execution. It was also observed positive effect of the presence of iron and potassium in the catalyst structure: betters conversions were observed for tests conducted with the catalyst CAADCM compared to CMADCM catalyst under the same conditions. The higher conversion was achieved for the test carried out at acid pH (3.0) with an initial concentration of phenol at 250 ppm catalyst in the presence of CAADCM at 1 g L-1 . The liquid samples taken every 15 minutes were analyzed by liquid chromatography identifying and quantifying hydroquinone, p-benzoquinone, catechol and maleic acid. Finally, a reaction mechanism is proposed, cogitating the phenol is transformed into the homogeneous phase and the others react on the catalyst surface. Applying the model of Langmuir-Hinshelwood along with a mass balance it was obtained a system of differential equations that were solved using the Runge-Kutta 4th order method associated with a optimization routine called SWARM (particle swarm) aiming to minimize the least square objective function for obtaining the kinetic and adsorption parameters. Related to the kinetic rate constant, it was obtained a magnitude of 10-3 for the phenol degradation, 10-4 to 10-2 for forming the acids, 10-6 to 10-9 for the mineralization of quinones (hydroquinone, p-benzoquinone and catechol), 10-3 to 10-2 for the mineralization of acids.

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Beamforming is a technique widely used in various fields. With the aid of an antenna array, the beamforming aims to minimize the contribution of unknown interferents directions, while capturing the desired signal in a given direction. In this thesis are proposed beamforming techniques using Reinforcement Learning (RL) through the Q-Learning algorithm in antennas array. One proposal is to use RL to find the optimal policy selection between the beamforming (BF) and power control (PC) in order to better leverage the individual characteristics of each of them for a certain amount of Signal to Interference plus noise Ration (SINR). Another proposal is to use RL to determine the optimal policy between blind beamforming algorithm of CMA (Constant Modulus Algorithm) and DD (Decision Direct) in multipath environments. Results from simulations showed that the RL technique could be effective in achieving na optimal of switching between different techniques.

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Barium Cerate (BaCeO3) is perovskite type structure of ABO3, wherein A and B are metal cations. These materials, or doped, have been studied by having characteristics that make them promising for the application in fuel cells solid oxide, hydrogen and oxygen permeation, as catalysts, etc .. However, as the ceramic materials mixed conductivity have been produced by different synthesis methods, some conditions directly influence the final properties, one of the most important doping Site B, which may have direct influence on the crystallite size, which in turn directly influences their catalytic activity. In this study, perovskite-type (BaCexO3) had cerium gradually replaced by praseodymium to obtain ternary type materials BaCexPr1-xO3 and BaPrO3 binaries. These materials were synthesized by EDTA/Citrate complexing method and the material characterized via XRD, SEM and BET for the identification of their structure, morphology and surface area. Moreover were performed on all materials, catalytic test in a fixed bed reactor for the identification of that person responsible for complete conversion of CO to CO2 at low operating temperature, which step can be used as the subsequent production of synthesis gas (CO + H2) from methane oxidation. In the present work the crystalline phase having the orthorhombic structure was obtained for all compositions, with a morphology consisting of agglomerated particles being more pronounced with increasing praseodymium in the crystal structure. The average crystal size was between 100 nm and 142,2 nm. The surface areas were 2,62 m²g-1 for the BaCeO3 composition, 3,03 m²g-1 to BaCe0,5Pr0,5O3 composition and 2,37 m²g-1 to BaPrO3 composition. Regarding the catalytic tests, we can conclude that the optimal flow reactor operation was 50 ml / min and the composition regarding the maximum rate of conversion to the lowest temperature was BaCeO3 to 400° C. Meanwhile, there was found that the partially replaced by praseodymium, cerium, there was a decrease in the catalytic activity of the material.

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This thesis develops a new technique for composite microstructures projects by the Topology Optimization process, in order to maximize rigidity, making use of Deformation Energy Method and using a refining scheme h-adaptative to obtain a better defining the topological contours of the microstructure. This is done by distributing materials optimally in a region of pre-established project named as Cell Base. In this paper, the Finite Element Method is used to describe the field and for government equation solution. The mesh is refined iteratively refining so that the Finite Element Mesh is made on all the elements which represent solid materials, and all empty elements containing at least one node in a solid material region. The Finite Element Method chosen for the model is the linear triangular three nodes. As for the resolution of the nonlinear programming problem with constraints we were used Augmented Lagrangian method, and a minimization algorithm based on the direction of the Quasi-Newton type and Armijo-Wolfe conditions assisting in the lowering process. The Cell Base that represents the composite is found from the equivalence between a fictional material and a preescribe material, distributed optimally in the project area. The use of the strain energy method is justified for providing a lower computational cost due to a simpler formulation than traditional homogenization method. The results are presented prescription with change, in displacement with change, in volume restriction and from various initial values of relative densities.

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This work concerns a refinement of a suboptimal dual controller for discrete time systems with stochastic parameters. The dual property means that the control signal is chosen so that estimation of the model parameters and regulation of the output signals are optimally balanced. The control signal is computed in such a way so as to minimize the variance of output around a reference value one step further, with the addition of terms in the loss function. The idea is add simple terms depending on the covariance matrix of the parameter estimates two steps ahead. An algorithm is used for the adaptive adjustment of the adjustable parameter lambda, for each step of the way. The actual performance of the proposed controller is evaluated through a Monte Carlo simulations method.

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INTRODUCTION: Humanized and quality prenatal and post-partum care is critical to maternal and newborn health, as well as oral health care. Currently, the National Oral Health Policy is aiming at expanding dental care for pregnant women. Thus, the promotion of oral health and attention to prenatal care policies should be integrated; however, there is still limited participation of pregnant women. Thus, it is necessary to verify the knowledge of pregnant women related to oral health, seeking to estimate the quality of dental care provided during prenatal care, being essential for the Family Health strategy to organize personnel, plan costs and to ensure the quality standard of care. OBJECTIVE: To develop and validate a research instrument on the knowledge of pregnant women about their oral health and of their baby. METHOD: This is a construction and validation study with 93 pregnant women in Family Health Units and specialized private clinics in Obstetrics, in the city of Natal / RN. It was authorized by the Onofre Lopes University Hospital Ethics Committee of the Universidade Federal do Rio Grande do Norte (UFRN) under the registration number 421.163/13. The construction of the instrument followed steps so that it was valid, reliable and sensitive: creation and reduction of the items (drafting of the instrument), content validity and testing of the instrument, and hypotheses validation. Once constructed, the instrument was evaluated by experts who suggested modifications. There was consultation with the target population about the new version of the created instrument, which had the instrument validation verified by internal consistency through intra and inter-calibration and test-retest. Next, the hypotheses were validated. A database was built in the Statistical Package for Social Sciences (SPSS), version 22.0. After creating the hypotheses, an association was found for validating the criteria between each of the specific issues for each established criteria, considering a 5% significance level. Data analysis was carried out by describing the absolute and relative frequencies of the variables pertaining to issues relating to their pregnancy knowledge about their oral health and their baby. The Kappa coefficient was used for the calibration process (Inter and Intra-examiner calibration) and Cronbach's alpha coefficient was used to analyze instrument reproducibility (test-retest). In addition, the chi-square test was used to cross the dependent variable with the (dichotomized) independent variables. RESULTS: The intra and inter agreement analysis presented a Kappa coefficient between 0.400 and 1.000. Internal consistency through the analysis showed that 90% of the instrument's questions showed great reliability in the answers (Cronbach α ˃ 0.7). In the investigation of the relationship between the dependent variable (knowledge about oral health) and the independent variables (trimester of pregnancy, education, income and multiparous), it was found that none of these independent variables were significantly associated. All hypotheses had their Ho confirmed. CONCLUSION: The constructed instrument was validated, considering that it showed to be sensitive with good reliability and good accuracy, and therefore can be used to assess pregnant women’s knowledge about their oral health and the oral health of their baby.

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INTRODUCTION: Humanized and quality prenatal and post-partum care is critical to maternal and newborn health, as well as oral health care. Currently, the National Oral Health Policy is aiming at expanding dental care for pregnant women. Thus, the promotion of oral health and attention to prenatal care policies should be integrated; however, there is still limited participation of pregnant women. Thus, it is necessary to verify the knowledge of pregnant women related to oral health, seeking to estimate the quality of dental care provided during prenatal care, being essential for the Family Health strategy to organize personnel, plan costs and to ensure the quality standard of care. OBJECTIVE: To develop and validate a research instrument on the knowledge of pregnant women about their oral health and of their baby. METHOD: This is a construction and validation study with 93 pregnant women in Family Health Units and specialized private clinics in Obstetrics, in the city of Natal / RN. It was authorized by the Onofre Lopes University Hospital Ethics Committee of the Universidade Federal do Rio Grande do Norte (UFRN) under the registration number 421.163/13. The construction of the instrument followed steps so that it was valid, reliable and sensitive: creation and reduction of the items (drafting of the instrument), content validity and testing of the instrument, and hypotheses validation. Once constructed, the instrument was evaluated by experts who suggested modifications. There was consultation with the target population about the new version of the created instrument, which had the instrument validation verified by internal consistency through intra and inter-calibration and test-retest. Next, the hypotheses were validated. A database was built in the Statistical Package for Social Sciences (SPSS), version 22.0. After creating the hypotheses, an association was found for validating the criteria between each of the specific issues for each established criteria, considering a 5% significance level. Data analysis was carried out by describing the absolute and relative frequencies of the variables pertaining to issues relating to their pregnancy knowledge about their oral health and their baby. The Kappa coefficient was used for the calibration process (Inter and Intra-examiner calibration) and Cronbach's alpha coefficient was used to analyze instrument reproducibility (test-retest). In addition, the chi-square test was used to cross the dependent variable with the (dichotomized) independent variables. RESULTS: The intra and inter agreement analysis presented a Kappa coefficient between 0.400 and 1.000. Internal consistency through the analysis showed that 90% of the instrument's questions showed great reliability in the answers (Cronbach α ˃ 0.7). In the investigation of the relationship between the dependent variable (knowledge about oral health) and the independent variables (trimester of pregnancy, education, income and multiparous), it was found that none of these independent variables were significantly associated. All hypotheses had their Ho confirmed. CONCLUSION: The constructed instrument was validated, considering that it showed to be sensitive with good reliability and good accuracy, and therefore can be used to assess pregnant women’s knowledge about their oral health and the oral health of their baby.

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This paper evaluate the performance of a Wastewater Treatment Plant (WWTP) in sequential batch activated sludge modality with tertiary treatment step, located in high temperature region. It also presents the analysis of organic matter’s removal and the evaluation of sludge sedimentation conditions through reactors in bench scale, fed with different substrate’s and biomass’ concentrations, from the WWTP in study. The results showed high efficiency and stability of the treatment process using Sequential Batch Reactors for domestic sewage, even with sudden changes of organic and hydraulic load, reaching more than 90% of efficiency in the removal of biodegradable organic matter. The removal of organic matter and sedimentation tests in bench reactors showed the good performance in respect of the organic matter’s removal, however, the high concentration of micro-organism results in a lower sludge sedimentation rate, which can compromise the quality of the final effluent. The relation Food/Microorganism in the conditions of the WWTP’s current operation showed a value of 0.06 gCOD/gVSS.d. and zonal sedimentation velocity of 0.59 m/h, the great ratio of the concentration of the substrate by biomass concentration, which obtained the maximum operational efficiency, showed a value of 0.09 gCOD/gVSS.d. and zonal sedimentation velocity of 1.4 m/h.

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This paper evaluate the performance of a Wastewater Treatment Plant (WWTP) in sequential batch activated sludge modality with tertiary treatment step, located in high temperature region. It also presents the analysis of organic matter’s removal and the evaluation of sludge sedimentation conditions through reactors in bench scale, fed with different substrate’s and biomass’ concentrations, from the WWTP in study. The results showed high efficiency and stability of the treatment process using Sequential Batch Reactors for domestic sewage, even with sudden changes of organic and hydraulic load, reaching more than 90% of efficiency in the removal of biodegradable organic matter. The removal of organic matter and sedimentation tests in bench reactors showed the good performance in respect of the organic matter’s removal, however, the high concentration of micro-organism results in a lower sludge sedimentation rate, which can compromise the quality of the final effluent. The relation Food/Microorganism in the conditions of the WWTP’s current operation showed a value of 0.06 gCOD/gVSS.d. and zonal sedimentation velocity of 0.59 m/h, the great ratio of the concentration of the substrate by biomass concentration, which obtained the maximum operational efficiency, showed a value of 0.09 gCOD/gVSS.d. and zonal sedimentation velocity of 1.4 m/h.

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Este protocolo objetiva esclarecer dúvidas existentes a respeito dos passos necessários para a reabilitação com próteses totais e parciais removíveis convencionais. Essas alternativas de tratamento são modalidades terapêuticas consagradas na literatura e podem devolver função mastigatória, estética, fonação e conforto ao paciente quando confeccionadas de maneira satisfatória. Elas representam também uma ótima opção para aqueles pacientes que não podem se submeter ao tratamento com implantes, por apresentarem limitações biológicas ou financeiras. A abordagem do protocolo clínico está dividida em duas partes. A primeira parte ilustra a reabilitação com próteses totais convencionais e a segunda, a reabilitação com próteses parciais removíveis convencionais em arcos inferiores com extremidade livre bilateral. Por meio da demonstração do passo a passo com fotos, dicas clínicas e resumos sistemáticos do conteúdo teórico contido nesse material, o aluno de Odontologia e o cirurgião-dentista poderão conhecer os passos necessários para executar estes tipos de reabilitações, desde o momento clínico de diagnóstico até o de controle e manutenção. Esperamos que essa obra desperte o interesse dos cirurgiões-dentistas por executar esses tipos de próteses e que os ajude a desenvolverem práticas e habilidades que melhorem o desempenho clínico dessas alternativas de tratamento.

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Este protocolo objetiva esclarecer dúvidas existentes a respeito dos passos necessários para a reabilitação com próteses totais e parciais removíveis convencionais. Essas alternativas de tratamento são modalidades terapêuticas consagradas na literatura e podem devolver função mastigatória, estética, fonação e conforto ao paciente quando confeccionadas de maneira satisfatória. Elas representam também uma ótima opção para aqueles pacientes que não podem se submeter ao tratamento com implantes, por apresentarem limitações biológicas ou financeiras. A abordagem do protocolo clínico está dividida em duas partes. A primeira parte ilustra a reabilitação com próteses totais convencionais e a segunda, a reabilitação com próteses parciais removíveis convencionais em arcos inferiores com extremidade livre bilateral. Por meio da demonstração do passo a passo com fotos, dicas clínicas e resumos sistemáticos do conteúdo teórico contido nesse material, o aluno de Odontologia e o cirurgião-dentista poderão conhecer os passos necessários para executar estes tipos de reabilitações, desde o momento clínico de diagnóstico até o de controle e manutenção. Esperamos que essa obra desperte o interesse dos cirurgiões-dentistas por executar esses tipos de próteses e que os ajude a desenvolverem práticas e habilidades que melhorem o desempenho clínico dessas alternativas de tratamento.

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The increasing prevalence of Repetitive Strain Injury / Work-Related Musculoskeletal Disorders (RSI / MSDs) has been explained by changes in the work that has been characterized by setting goals and productivity. This fact does not take into account the psycho-physiological characteristics of workers who become ill as a result of professional activities engaged in and also the adverse conditions in which his work was done. This study aimed to analyze the RSI / MSDs reported in the state of Rio Grande do Norte, Brazil, 2010-2014 compared to the profile of the population, epidemiological aspects and features of these diseases. It is a descriptive epidemiological cross-sectional study using secondary data obtained in the Notifiable Diseases Information System (SINAN) in May 2015 was used as the area covered by the Rio Grande do Norte. Data were collected regarding the grievances of work-related RSI / MSDs, assigned by the Worker's Health Reference Center (CEREST) of the State Health Department. Data were processed with the help of Microsoft Excel® 2013 and presented in tables in absolute frequency (n) and relative frequency (%). The results showed a total of 403 notifications of RSI / MSDs, where the vast majority 72% (290) was recorded in Natal. Regarding the profile of notified employees, 88.59% (357) have aged between 25 and 54 years, 62.78% (253) were female, and in relation to education, 31.51% (127) had high school complete. The most affected occupations were seamstresses (the clothing industry) with 24.97% (97), followed by masons, construction with 3.23% (13) and cashiers with 2.99% (12). About the work situation, 75.93% (306) had a formal contract, however, were sent to Communications Occupational accidents (CAT) only 67% (270) of the cases. Regarding the signs and symptoms, pain and limitation of movement were the most mentioned respectively with 98.01% (395) and 95.04% (383) of notifications. Notifications, 94.29% (380) showed exposure to repetitive movements in their workplace. The most frequent specific diagnoses were synovitis and tenosynovitis (CID F 65), with 30.02% (121) of notifications, followed by back pain (CID F 54) to 19.35% (78) and shoulder injuries (ICD M 75) with 15.88% (64). They were away from work 81.64% (329) of workers reported with RSI / MSDs. Evolution more prevalent among cases was temporary disability with 75.68% (305). It was concluded that the SINAN is a database of potential to characterize the profile of RSI / MSDs, requiring, however, an improvement in the coverage of records and data quality. In addition, this study reflects the need to implement protection strategies to workers by companies, signaling promotion, prevention and rehabilitation aimed at reducing these injuries and the improvement of occupational health indicators in Rio Grande do Norte.

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In this work are considered two bidimensional systems, with distints chacacteristcs and applicabilitys. Is studied the adsorption of transition metals (MT) Fe, Co, Mn and Ru in extended defects, formed by graphene grain boundaries. First in pristine graphene The hollow site of carbon hexagon, in pristine graphene, are the most stable for MT adsorption. The Dirac cone in eletronic structure of graphene was manteined with the presence of MT. For the considered grain boundaries the MT has a greater stability for absorption in the grain boundaries sites in comparison with pristine graphene. Through the energy barrier values, are observed diffusion chanels for MT localized on the grain boundaries. This diffusion chanels indicate a possible formation of nanolines of MT in graphene. For the first stage of the nanolines, ate observed a better stability for the system with greater MT concentration, due to MT-MT interactions. Also, due to the magnetic moment of the MT, the nanolines show a magnetization. For the most stable configurations the system are metallics, particularly for Fe the band structure indicates an anisotropic spin current. In a second study, are considereted the retention capacity for metallic contaminants Cd and Hg in clayminerals, kaolinite (KAO) and montmorillonite (MMT). Through the adsorption energies of contaminantes in the clayminerals, was observed a increase in stability with the increase of contaminants concentration, due to the interaction Cd-Cd and Hg-Hg. Also, was observed that KAO has a strong interaction beteween monolayers than MMT. In this sence, for the adsoption process of contaminantes in the natural form of KAO and MMT, the latter has a better retention capacity, due to the small net work for contaminant intercalation. However, when the modification of clayminerals, with molecules that increase the spacing between monolayers, exist a optimal condition, which the contaminant absorption are more stable in KAO system than in MMT. In the Langmuir adsorption model for the clayminerals in the optimal monolayer spacing, the retention capacity for Cd and Hg in KAO system are 21% greater than in MMT system. Also, for the X-ray Absorption Near Edge Spectroscopy (XANES) for the K edge of Cd and Hg, are found a positive shift of absorption edge with the decreasing of monolayer spacing. This result indicates a possible way to determine the concentration of adsorbed contaminats in relation to unabsorbed ones, from the decomposition of experimental XANES in the obteined spectras.

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In this work, it was developed and validated methodologies that were based on the use of Infrared Spectroscopy Mid (MIR) combined with multivariate calibration Square Partial Least (PLS) to quantify adulterants such as soybean oil and residual soybean oil in methyl and ethyl palm biodiesels in the concentration range from 0.25 to 30.00 (%), as well as to determine methyl and ethyl palm biodiesel content in their binary mixtures with diesel in the concentration range from 0.25 to 30.00 (%). The prediction results showed that PLS models constructed are satisfactory. Errors Mean Square Forecast (RMSEP) of adulteration and content determination showed values of 0.2260 (%), with mean error (EM) with values below 1.93 (%). The models also showed a strong correlation between actual and predicted values, staying above 0.99974. No systematic errors were observed, in accordance to ASTM E1655- 05. Thus the built PLS models, may be a promising alternative in the quality control of this fuel for possible adulterations or to content determination.