996 resultados para Caminho de Menor Custo
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O uso de cultivares selecionadas é uma das tecnologias de mais fácil adoção pelo agricultor, pois além de incrementar a produtividade, é um dos insumos de menor custo na produção agrícola. Assim, é fundamental obter informações sobre o desempenho de novas cultivares, nas mais diversas regiões de cultivo. Objetivou-se, neste trabalho avaliar o comportamento de cultivares de arroz de terras altas (Oryza sativa L.) (BRS Aroma, BRS Bonança, BRS Colosso, BRSMG Conai, BRSMG Curinga, BRS Soberana, BRS Talento e IAC 202), sob condições de sequeiro, na região de Cassilândia, MS. O delineamento experimental foi o de blocos ao acaso, com quatro repetições. A semeadura foi realizada em 30 de novembro de 2005, no espaçamento de 0,40 m entre linhas e 70 sementes viáveis por metro. As cultivares BRS Talento, IAC 202 e BRS Soberana apresentaram comportamento superior. As cultivares BRS Soberana, BRS Bonança, BRS Colosso, IAC 202 e BRS Talento apresentaram maior rendimento de grãos inteiros. É possível obterse boa produtividade (acima de 3.000 kg ha-1), na cultura do arroz de terras altas sob condições de sequeiro no município de Cassilândia, MS, desde que sejam utilizadas cultivares adequadas.
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Among the main challenges in the beer industrial production is the market supply at the lowest cost and high quality, in order to ensure the expectations of customers and. consumers The beer fermentation stage represents approximately 70% of the whole time necessary to its production, having a obligatoriness of strict process controls to avoid becoming bottleneck in beer production. This stage is responsible for the formation of a series of subproducts, which are responsible for the composition of aroma/bouquet existing in beer and some of these subproducts, if produced in larger quantities, they will confer unpleasant taste and odor to the final product. Among the subproducts formed during the fermentation stage, total vicinal diketones is the main component, since it is limiting for product transfusion to the subsequent steps, besides having a low perception threshold by the consumer and giving undesirable taste and odor. Due to the instability of main raw materials quality and also process controls during fermentation, the development of alternative forms of beer production without impacting on total fermentation time and final product quality is a great challenge to breweries. In this work, a prior acidification of the pasty yeast was carried out, utilizing for that phosphoric acid, food grade, reducing yeast pH of about 5.30 to 2.20 and altering its characteristic from flocculent to pulverulent during beer fermentation. An increase of six times was observed in amount of yeast cells in suspension in the second fermentation stage regarding to fermentations by yeast with no prior acidification. With alteration on two input variables, temperature curve and cell multiplication, which goal was to minimize the maximum values for diketones detected in the fermenter tank, a reduction was obtained from peak of formed diacetyl and consequently contributed to reduction in fermentation time and total process time. Several experiments were performed with those process changes in order to verify the influence on the total fermentation time and total vicinal diketones concentration at the end of fermentation. This experiment reached as the best production result a total fermentation time of 151 hours and total vicinal diketone concentration of 0.08 ppm. The mass of yeast in suspension in the second phase of fermentation increased from 2.45 x 106 to 16.38 x 106 cells/mL of yeast, which fact is key to a greater efficiency in reducing total vicinal diketones existing in the medium, confirming that the prior yeast acidification, as well as the control of temperature and yeast cell multiplication in fermentative process enhances the performance of diketones reduction and consequently reduce the total fermentation time with diketones concentration below the expected value (Max: 0.10 ppm)
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Stabilization pond is the main technology used for treatment wastewater, in northeast Brazil, due to lower cost of deployment, operation and maintenance compared to other technologies. Most systems of stabilization ponds has been in operation for some time, on average 10 years of operation, receiving high organic loads and do not have good removal efficiencies of the main parameters for which have been designed. Therefore it is necessary to work to quantify the efficiency of current systems. This study evaluated the biodegradability of organic matter in raw sewage, the removal of organic matter in reactors and determination of the kinetic constant removal of organic matter (k), both in reactors and in raw sewage, based on the analysis made in the laboratory and through mathematical methods proposed in the literature, in nine systems stabilization ponds, located in Rio Grande do Norte. In relation the degradation kinetics in stabilization ponds, it was observed that many papers published in the literature were obtained in pilot-scale systems, which often, due to the action of external factors such as wind and temperature, these can t be considered as a reference in the analysis of the kinetic constant K, so the need for more research into systems of scale. This study had three distinct phases and simultaneous, routine monitoring, study of the daily cycle and the determination of kinetic constant of degradation of organic matter (K). The monitoring showed that the removal efficiencies of organic matter on most systems were lower than suggested by the literature, the best efficiencies of around 76% (BOD) and 72% (COD) and the worst of the order of 48% (BOD) and 55% (COD). The calculation of K in raw sewage (Ke) was within the range of variation expected in the literature (0.35 to 0.60 days-1). Already for the results obtained for K in the reactors (Kr), there were well below the values recommended in the literature (0.25 to 0.40 d-1 for complete mix and from 0.13 to 0.17 d-1 for flow dispersed), in line with the overloads that organic systems are subject
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This dissertation presents a methodology to the optimization of a predial system of cold water distribution. It s about a study of a case applied to the Tropical Buzios Residential Condominium, located in the Búzio s Beach, Nísia Floresta city, the east coast of the Rio Grande do Norte state, twenty kilometers far from Natal. The design of cold water distribution networks according to Norm NBR 5626 of the ABNT - Brazilian Association of Techniques Norms, does not guarantee that the joined solution is the optimal solution of less cost. It s necessary the use of an optimization methodology, that supplies us, between all the possible solutions, the minimum cost solution. In the optimization process of the predial system of water distribution of the Tropical Búzios Condominium, is used Method Granados, that is an iterative algorithm of optimization, based on the Dynamic Programming, that supplies the minimum cost s network, in function of the piezometric quota of the reservoir. For the application of this Method in ramifies networks, is used a program of computer in C language. This process is divided in two stages: attainment of the previous solution and reduction of the piezometric quota of headboard. In the attainment of the previous solution, the minors possible diameters are used that guarantee the limit of maximum speed and the requirements of minimum pressures. The piezometric quota of headboard is raised to guarantee these requirements. In the second stage of the Granados Method, an iterative process is used and it objective is to reduce the quota of headboard gradually, considering the substitution of stretches of the network pipes for the subsequent diameters, considering a minimum addition of the network cost. The diameter change is made in the optimal stretch that presents the lesser Exchange Gradient. The process is locked up when the headboard quota of desired is reached. The optimized network s material costs are calculated, and is made the analysis of the same ones, through the comparison with the conventional network s costs
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Este artigo apresenta os principais resultados e o detalhamento da metodologia e equações de controle de um retificador monofásico pré-regulador de 150kW para sistema trólebus. A estrutura proposta possibilita a Correção ativa do Fator de Potência (CFP) com baixos níveis de Distorção Harmônica Total (DHT) na corrente, em conformidade com a norma internacional IEC 61000-3-4. Fruto de um projeto de Pesquisa, Desenvolvimento e Inovação (P) junto à empresa AES Eletropaulo Metropolitana de São Paulo, em parceria com a empresa de transporte Himalaia S.A., o projeto possui como principais objetivos estimular o interesse para a expansão das linhas de trólebus a partir de uma plataforma de alimentação de menor custo de instalação e manutenção, sem a necessidade de subestações retificadoras, e, com vistas a promover a melhoria da qualidade de vida nos grandes centros urbanos. Nessa nova modalidade proposta para o sistema de alimentação, o trólebus pode ser alimentado tanto pelas redes convencionais em corrente contínua (CC) quanto pelas redes de distribuição em corrente alternada (CA), mantendo-se a disposição a dois fios dos sistemas CC, sendo as mudanças de rede de alimentação (CC ou CA) monitoradas e controladas digitalmente. Todo o sistema de gerenciamento e controle do conversor é realizado digitalmente por FPGA XC3S200. Na evolução do sistema proposto, os autores pretendem inclusive eliminar as linhas aéreas de alimentação, através da utilização de postos de alimentação em CA, especialmente desenvolvidos para os pontos de embarque/desembarque de passageiros para este veículo de transporte coletivo, eliminando-se os aspectos visuais negativos das redes de alimentação deste modal, e, reduzindo-se as falhas de operação do sistema.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The processing of heavy oil produced in Brazil is an emergency action and a strategic plan to obtain self-sufficiency and economic surpluses. Seen in these terms, it is indispensable to invest in research to obtain new catalysts for obtaining light fraction of hydrocarbons from heavy fractions of petroleum. This dissertation for the degree of Doctor of Philosophy reports the materials preparation that combine the high catalytic activity of zeolites with the greater accessibility of the mesoporosity, more particularly the HZSM-5/MCM-41 hybrid, done by synthesis processes with less environmental impact than conventional ones. Innovative methodologies were developed for the synthesis of micro-mesoporous hybrid material by dual templating mechanism and from crystalline zeolitic aluminosilicate in the absence of organic template. The synthesis of hybrid with pore bimodal distribution took place from one-single organic directing agent aimed to eliminate the use of organic templates, acids of any kind or organic solvents like templating agent of crystalline zeolitic aluminosilicate together with temperature-programmed microwave-assisted, making the experimental procedures of preparation most practical and easy, with good reproducibility and low cost. The study about crystalline zeolitic aluminosilicate in the absence of organic template, especially MFI type, is based on use of H2O and Na+ cation playing a structural directing role in place of an organic template. Advanced characterization techniques such as X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Highresolution Transmission Electron Microscopy (HRTEM), Adsorption of N2 and CO2, kinetic studies by Thermogravimetric Analysis (TGA) and Pyrolysis coupled to Gas Chromatography/Mass Spectrometry (Pyrolysis-GC/MS) were employed in order to evaluate the synthesized materials. Achieve the proposed objectives, has made available a set of new methodologies for the synthesis of zeolite and hybrid micro-mesoporous material, these suitable for catalytic pyrolysis of heavy oils aimed at producing light fraction
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The development of more selective and sensitive analytical methods is of great importance in different areas of knowledge, covering, for example, food, biotechnological, environmental and pharmaceutical sectors. The study aimed to employ the technique electroanalytical differential pulse voltammetry (DPV) as an innovative and promising alternative for identification and quantification of organic compounds. The organic compounds were investigated in this study oxalic acid (OA) and folic acid (FA). The electrochemical oxidation of oxalic acid has been extensively studied as a model reaction in the boundary between the organic and inorganic electrochemistry. Since the AF, an essential vitamin for cell multiplication in all tissues, which is essential for DNA synthesis. The AF has been investigated using analytical techniques, liquid chromatography and molecular absorption spectrophotometry. The results obtained during the experimental procedure indicated that the process of electrochemical oxidation of oxalic acid is strongly dependent on the nature of the anode material and the oxidation mechanism, which affects their detection. Efficient removal was observed in Ti/PbO2 anodes, graphite, BDD and Pt 90, 85, 80 and 78% respectively. It was also shown that the DPV employing glassy carbon electrode offers a fast, simple, reliable and economical way to determine the AO during the process of electrochemical oxidation. Furthermore, electroanalytical methods are more expensive than commonly used chromatographic analysis and other instrumental methods involving toxic reagents and higher cost. Compared with the classical method of titration and DPV could be a good fit, confidence intervals and detection limits confirming the applicability of electroanalytical technique for monitoring the degradation of oxalic acid. For the study of AF was investigated the electrocatalytic activity of the carbon paste electrode for identification and quantification in pharmaceutical formulations by applying the DPV. The results obtained during the experimental procedure showed an irreversible oxidation peak at 9.1 V characteristic of FA. The carbon paste sensor showed low detection limit of 5.683×10−8 mol L-1 reducing matrix effects. The spectrophotometric analysis showed lower concentrations of HF compared with those obtained by HPLC and DPV. The levels of AF were obtained according to the methodology proposed by the Brazilian Pharmacopoeia. The electroanalytical method (DPV) proposed is cheaper than GC analysis commonly used by the pharmaceutical industry. The results demonstrated the potential of these electroanalytical techniques for future applications in environmental, chemical and biological sensors
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The crisis that the Brazilian State have been crossing throughout the last decades has revealed intense oscillations in the the way of life of the population reality. In the health area, specifically of buccal health, new alternatives of attending to demands for odontological services have been increasing from the 1990 decade. The research had as objective to analyze the demand of the services of the clinic-school of odontology of the UFRN to identify the socio-economic profile of the users and the inflections of the standards of the National Politics of Buccal Health. The methodology is based on a dialectic perspective and a quali-quantitative boarding. It was used as instrument of data collection forms with open and closed questions, applied to two distinguished groups of citizens: 53 users of the services and 12 pupils of 9th and 10th term of the Odontology Course. The results reaffirm that, with the aggravation of the crisis of SUS (Sistema Único de Saúde- Single Health System) grow the difficulties of accessing the odontological services of the users majority. The subjects of the research make use of a regular socio-economic condition, with high school, own house, formal bond to labor and monthly medium income between 1 and 2 minimum wages. The conclusive analyses point to the selective and exculpatory character of the buccal health right, mainly, those users who find themselves in situation of extreme poverty and social vulnerability. Immediate and of lesser cost odontological assistance is what it s aimed, but the standards praised in the Public Politics of Buccal Health walk in another direction, requiring a bigger strongness of the formation bases and implementation of the programmatical actions since the academic field until the effectiveness of Politics of Buccal Health as a right while as a right to attention and care
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This work consists on the study of two important problems arising from the operations of petroleum and natural gas industries. The first problem the pipe dimensioning problem on constrained gas distribution networks consists in finding the least cost combination of diameters from a discrete set of commercially available ones for the pipes of a given gas network, such that it respects minimum pressure requirements at each demand node and upstream pipe conditions. On its turn, the second problem the piston pump unit routing problem comes from the need of defining the piston pump unit routes for visiting a number of non-emergent wells in on-shore fields, i.e., wells which don t have enough pressure to make the oil emerge to surface. The periodic version of this problem takes into account the wells re-filling equation to provide a more accurate planning in the long term. Besides the mathematical formulation of both problems, an exact algorithm and a taboo search were developed for the solution of the first problem and a theoretical limit and a ProtoGene transgenetic algorithm were developed for the solution of the second problem. The main concepts of the metaheuristics are presented along with the details of their application to the cited problems. The obtained results for both applications are promising when compared to theoretical limits and alternate solutions, either relative to the quality of the solutions or to associated running time
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Objetivo: Simplificar o cálculo do índice prognóstico inflamatório nutricional (IPIN) empregando número menor de variáveis com conseqüente redução do custo da análise. Materiais e métodos: Foram estudados 54 pacientes e 12 indivíduos-controle com 48 ± 20 (média ± dp) anos de idade. As principais patologias dos pacientes eram: doença arterial periférica (22), pênfigo foliáceo (7), doença inflamatória intestinal (7), trauma (6) e pós-operatório de ortognatia (3). Foram obtidas amostras de sangue periférico, colhidas em jejum para dosagens de proteínas positivas (+) e negativas (-) de fase aguda (PFA) pelo método nefelométrico. Proteína C reativa (PCR), alfa-1-glicoproteína-ácida (alfa-1-GA), alfa-1-antitripsina (alfa-1-AT) e ceruloplasmina (CER) foram as PFA+ e albumina (Alb), transtiretina (TTR), transferrina (TF) e proteína ligadora do retinol (RBP) foram as representantes das PFA-. Esses valores foram analisados quanto à associação de correlação isolada ou associadamente na fórmula do índice prognóstico inflamatório e nutricional (IPIN = PCR + alfa-1-GA / Alb + TTR). de acordo com o índice prognóstico inflamatório e nutricional, os pacientes foram classificados em grupo-controle (G1); pacientes sem infecção/inflamação (IPIN < 1, G2) ou com risco de inflamação/infecção (IPIN > 1, G3). em seguida os pacientes do G3 foram subdivididos em baixo risco (G3A, n = 16); médio risco ( G3B, n = 10); alto risco (G3C, n = 6) e com risco de morte (G3D, n = 11). Os resultados foram correlacionados entre si (teste de Spearman) ou submetidos às comparações entre grupos (teste de Kruskall-Wallis). Resultados: Houve relação significativa entre as variáveis PCR ´ alfa-1-GA (r = 0,49), Alb ´ TTR (r = 0,60), Alb ´ RBP (r = 0,58), Alb ´ TF (r = 0,39), TTR ´ RBP (r = 0,56) e TTR´ TF (r = 0,43) e as melhores relações encontradas entre PFA+ e PFA- foram: PCR ´ Alb (r = - 0,71), PCR ´ TTR (r = - 0,54), PCR ´ TF (r = - 0,39) e alfa-1-GA ´ Alb (r = - 0,35). Os valores do IPIN mostraram a diferenciação G3 > (G1 = G2) e G3 > G3A. Entre todas as proteínas dosadas apenas PCR, Alb e TTR discriminaram os grupos: sendo G3 > (G1= G2) para PCR e G3< (G1= G2) para Alb e TTR. Apenas PCR, TTR e TF discriminaram a morbimortalidade com G3D > G3A (para PCR) e G3D < G3A (para TTR e TF). PCR/Alb e IPIN apresentaram concordância de valores para os riscos de complicações. Conclusão: Assim, conclui-se pela possibilidade de substituição do IPIN pela relação PCR/albumina, mais simples e de menor custo, mantendo-se o mesmo poder e sensibilidade para diagnóstico dos graus de risco de complicações.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Objetivou-se avaliar o desempenho de cabritos de três grupos raciais. Foram considerados nas avaliações o peso, o ganho de peso, as medidas biométricas, a conversão alimentar e o custo de produção relativo à alimentação. Utilizaram-se 41 cabritos, machos e fêmeas, de três grupos raciais (A - Alpino; ½ BA - ½ Boer + ½ Alpino; e ¾ BA - ¾ Boer + ¼ Alpino), avaliados aos 60, 90 e 120 dias em sistema de confinamento. As médias foram comparadas por análise de variância utilizando-se o teste Tukey. O desempenho não diferiu entre os grupos raciais. O escore corporal foi maior nos animais ¾ BA, o que pode representar vantagem econômica ao produtor se esses animais forem comercializados vivos. Com o avanço da idade, houve aumento do comprimento corporal, da altura anterior, da altura posterior, do perímetro torácico, do perímetro da perna, da largura da garupa e da largura do peito. Os machos foram superiores às fêmeas quanto às medidas biométricas e quanto ao peso ao nascimento, aos 60 e aos 90 dias. Os machos Alpinos foram mais pesados aos 120 dias e apresentaram, ainda, maior ganho de peso no intervalo dos 30 aos 60 dias. O menor custo de produção relativo à alimentação por quilograma de cabrito produzido foi observado aos 90 dias de idade.
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Foram avaliadas três formas de parcelas experimentais (retangular, uma linha - linear e parcela de uma árvore - STP) em testes clonais de Eucalyptus spp, utilizando-se três experimentos, cada um com 18 clones. Foram usados três modelos de análise (mínimos quadrados ordinários - ANOVA tradicional, modelos mistos com fator clone fixo ou com fator clone aleatório - REML/BLUP). Os dois primeiros modelos apresentaram resultados similares. Com REML/BLUP houve estreitamento das predições em relação às amplitudes obtidas com as médias, e essa redução foi proporcionalmente maior com parcelas retangulares e STP. O ordenamento dos clones também foi similar com esses dois tipos de parcelas. É provável que com parcelas STP haja um balanço compensatório das alocompetições, pois se pode trabalhar com maior número de repetições e menor custo. Portanto, com parcelas STP haverá economia de recursos e sem prejuízos para o Programa de Melhoramento Florestal.
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O presente experimento foi realizado com o objetivo de avaliar o desempenho de cordeiros em confinamento alimentados com dieta exclusiva de concentrado com diferentes porcentagens de proteína. Foram utilizados 24 cordeiros mestiços da raça Santa Inês, não castrados, com aproximadamente 180 dias de idade, peso vivo médio de 25kg, confinados, num delineamento experimental inteiramente ao acaso, com quatro tratamentos e seis repetições. O consumo voluntário de matéria seca, matéria orgânica, proteína bruta e nutrientes digestíveis totais, além do ganho de peso diário e total, da conversão e da eficiência alimentar dos cordeiros, não foram influenciados (P>0,05) pela porcentagem de proteína na dieta. As dietas com 18 e 20% de proteína bruta apresentaram menores custos de produção, entretanto o menor custo foi obtido com a ração contendo 18% de PB.