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Eletrólitos sólidos homogêneos e heterogêneos : obtenção e caracterização visando aplicação em células A combustível de temperatura intermediária
(Universidade Federal de São Carlos, 2016-03-04) Antunes, Fábio Coutinho; Andretta, Marcello Rubens Barsi; https://lattes.cnpq.br/7904227795652627; Souza, Dulcina Maria Pinatti Ferreira de; https://lattes.cnpq.br/4100119317525940; https://lattes.cnpq.br/9066668470271550
Emission reduction of greenhouse gases to the atmosphere in order to control global warming is an urgent need fully accepted by the international community. Ceramic materials play an important role in the possible solutions for this problem, with emphasis on 8 mol% Yttria-Stabilized Zirconia (8YSZ). 8YSZ is the state of the art material for high temperature Solid Oxide Fuel Cell (SOFC) electrolytes, however its ionic conductivity is not high enough to enable cell operation at intermediate temperatures (T~600°C), which are considered to be optimal for technological feasibility, considering cost, efficiency and life span. The goal of this work was to investigate the role of new interfaces in electrolytes with 8YSZ as the major phase, in order to obtain ceramic materials with unique microstructures, as well as higher conductivity than conventional ones. In order to achieve this goal, the following were investigated: i) homogeneous composite consisting of 8YSZ single crystals dispersed and oriented in 8YSZ polycrystalline matrix; ii) heterogeneous composite formed by Al2O3 single crystals (sapphire) dispersed and oriented in 8YSZ polycrystalline matrix; iii) heterogeneous composite consisting of intercalated layers of 8YSZ and Al2O3 polycrystalline films, which were deposited on Al2O3 mono and polycrystalline substrates. All analyzed systems showed higher electrical conductivity than 8YSZ samples with conventional microstructure. Emphasis should be made to the homogeneous composite (8YSZ polycrystalline matrix with 8YSZ monocrystalline fiber oriented) which showed electrical conductivity 18 times higher than 8YSZ with conventional microstructure, which can enable SOFC operation at intermediate temperatures.
Sistema embarcado reconfigurável de forma estática por programação genética utilizando hardware evolucionário híbrido
(Universidade Federal de São Carlos, 2016-03-04) Almeida, Manoel Aranda de; Pedrino, Emerson Carlos; https://lattes.cnpq.br/6481363465527189; https://lattes.cnpq.br/2889169146811970
The use of technology based on Field Programmable Gate Arrays (FPGAs), a reconfigurable technology, has become a frequent object of study. This technique is feasible and a promising application in the development of embedded systems, however, the difficulty in finding a flexible and efficient way to perform such an application is their bigger problem. In this work, a virtual and reconfigurable architecture (AVR) in FPGA for hardware applications is presented using a Genetic Programming Software on the development of an optimal reconfiguration for this AVR, in order to build a hardware capable of performing a given task in an embedded system. This proposal is a simple, flexible and efficient way to achieve appropriate applications in embedded systems, when compared to other reconfigurable hardware techniques. The representation of phenotype of the proposed evolutionary system is based on a bi-dimensional network function elements (EF). The GPLAB tool for MATLAB is used in Genetic Programming, and the solution found by this procedure is converted into a memory mapping to represent the best solution, where it is used to reconfigure the hardware. In the tests, GPLAB found results for logic circuits in a few generations, and for image filters containing efficient solutions, where there was little hardware occupation, especially memory, in the cases this has been presented, with a reduced chromosome size, shows a proposal efficiency.
Democracia e política na obra de Florestan Fernandes : o momento de interpretação do Brasil (1960-1975)
(Universidade Federal de São Carlos, 2016-03-04) Mazucato, Thiago Pereira da Silva; Cepêda, Vera Alves; https://lattes.cnpq.br/4917331423373631; https://lattes.cnpq.br/7348071393470097
This work aimed to analyze the theoretical and conceptual shifts in a group of books of Florestan Fernandes published in the period 1960-1975 we consider to be their works of interpretation of Brazil: Social Changes in Brazil (1960), The Sociology in an Age of Social Revolution (1962), Class Society and Underdevelopment (1968), Dependent Capitalism and Social Classes in Latin America (1973) and The Burgeois Revolution in Brazil (1975). The general question that guided the research was to investigate how the issue of democracy appears in this Works, crossing their reflections on topics such as dependency, underdevelopment and planning, all issues related to the sphere of Policy, and was adopted the methodological perspective of linguistic contextualism (Reinhart Koselleck, Quentin Skinner, John Pocock) to analyze the theoretical and conceptual shifts of Florestan Fernandes in these works.
Influência da composição química foliar na colonização por larvas de Chironomidae (Diptera) durante a decomposição em riachos
(Universidade Federal de São Carlos, 2016-03-04) Rossi, Luciene Aparecida Leite; Santino, Marcela Bianchessi da Cunha; https://lattes.cnpq.br/2356641063223397; Strixino, Susana Trivinho; https://lattes.cnpq.br/1804083229761186; https://lattes.cnpq.br/9260211676131094
With the purpose of elucidating some aspects concerning the influence of leaf chemical composition on Chironomidae (Diptera) larvae colonization and their role in decomposition, field experiments were carried out here presented in four chapters: i) Chemical and elemental composition of leaf litter of Hedychium coronarium, Pteridium arachnoideum and Magnolia ovata during decomposition in a low-order stream; ii) Influence of leaf chemical composition in the colonization of Hedychicium coronarium, Pteridium arachnoideum and Magnolia ovata leaf litters by Chironomidae (Diptera) larvae; iii) Feeding habits of the Chironomidae (Diptera) larvae and their contribution to the consumption of plant tissues during decomposition in low order streams; iv) Influence of Chironomidae (Diptera) larvae in the kinetics of aerobic decomposition of Hedychium coronarium, Pteridium arachnoideum and Magnolia ovata leaf litters. The experiments were performed in low order streams in São Carlos-SP and consisted on incubation of polyethylene bottles with small holes containing dried leaves of the three plant species, being removed from time to time over 85 days. Overall, the results indicated that: i) the invader leaf litter showed major quantities of refractory and allelopathic materials than native one; ii) differences in the leaf litter chemical composition influenced the Chironomidae larvae colonization; iii) the chironomids feeding habits differed among plant species and vary with the time of incubation of the leaf litter, amount of remaining mass and adhered organic matter; iv) Chironomidae larvae, mainly shredders, that colonize leaf litters can influence mass loss.
Remodelamento da matriz extracelular e respostas cardíacas funcionais em ratos idosos submetidos a treinamento resistido
(Universidade Federal de São Carlos, 2016-03-04) Guzzoni, Vinicius; Davel, Ana Paula; https://lattes.cnpq.br/0575590472541198; Araújo, Heloísa Sobreiro Selistre de; https://lattes.cnpq.br/4065824911933203; https://lattes.cnpq.br/5203492561212860
INTRODUCTION: It is well documented that aging causes morphological and functional alterations in the heart. Cardiac ECM remodeling is one event of structural changes in left ventricle (LV), which is modulated by MMPs/TIMPs balance and may lead to cardiac fibrosis. To prevent such effects inherent of aging, aerobic exercise training has been suggested to improve the cardiac fibrosis and function. However the effects of resistance training (RT) remains unclear. Whether that RT could alter cardiac function following cardiac ECM remodeling is uncertain. PURPOSE: to investigate the chronic effects of high intensity resistance training (RT) in the extracellular matrix (ECM) remodeling of left ventricle (LV) and cardiac function in old rats. PROCEDURES: Rats with 3 and 21 months-age were assigned as young sedentary (YS), young trained (YT), old sedentary (OS) and old trained (OT). The trained groups (YT and OT) were submitted to high-intensity RT protocol (3 times a week during 12 weeks). After 48h post-training, hemodynamic and intra-ventricular pressures were recorded. LV myocyte width, LV connective tissue and collagen fibrils were analyzed. MMP-2 activity, gene and protein expression from ECM components as well as angiotensin II (Ang-II) and atrial natriuretic peptide (ANP) were evaluated FINDINGS: LV myocyte width and connective tissue were reduced in OT rats. RT increased the MMP-2 activity in OT rats and improved the agerelated increase in the left ventricle end diastolic pressure (LVEDP). The RT unchanged Ang-II and ANP in LV of old rats. CONCLUSION: RT was effective to decrease LV connective tissue, which was associated with increased ECM remodeling by MMP-2 activity in LV tissue and improvement of LVEDP in aging rats. Our results point out the importance of RT in ECM homeostasis and diastolic function in experimental aging model.
Conjunto frente de ondas em classe de funções ultradiferenciáveis de soluções de equações diferenciais parciais lineares
(Universidade Federal de São Carlos, 2016-03-04) Oliveira, Renata de; Barostichi, Rafael Fernando; https://lattes.cnpq.br/3582461114222090; https://lattes.cnpq.br/0208377857169816
In this work, we introduce the wave front set WF,(u) of a classical distribution with respect to the ultradifferentiable classes of Beurling and Eomieu type. Our main goal is to present a detailed proof of the inclusion WF*(u) c WF^(Pu) U Char P, Vu e V(Q). In the above expression, Q is an open subset of Rn, P is a linear partial differential operator with coefficients in a suitable ultradifferentiable class and Char P is the characteristic set P
Aprendizado sem-fim de paráfrases
(Universidade Federal de São Carlos, 2016-03-04) Polastri, Paulo César; Caseli, Helena de Medeiros; https://lattes.cnpq.br/6608582057810385; https://lattes.cnpq.br/1341941141535178
Use different words to express/convey the same message is a necessity in any natural language and, as such, should be investigated in research in Natural Language Processing (NLP). When it is just a simple word, we say that the interchangeable words are synonyms; while the term paraphrase is used to express a more general idea and that also may involve more than one word. For example, the sentences "the light is red" and "the light is closed" are examples of paraphrases as "sign" and "traffic light" represent synonymous in this context. Proper treatment of paraphrasing is important in several NLP applications, such as Machine Translation, which paraphrases can be used to increase the coverage of Statistical Machine Translation systems; on Multidocument Summarization, where paraphrases identification allows the recognition of repeated information; and Natural Language Generation, where the generation of paraphrases allows creating more varied and fluent texts. The project described in this document is intended to verify that is possible to learn, in an incremental and automatic way, paraphrases in words level from a bilingual parallel corpus, using Never-Ending Machine Learning (NEML) strategy and the Internet as a source of knowledge. The NEML is a machine learning strategy, based on how humans learn: what is learned previously can be used to learn new information and perhaps more complex in the future. Thus, the NEML has been applied together with the strategy for paraphrases extraction proposed by Bannard and Callison-Burch (2005) where, from bilingual parallel corpus, paraphrases are extracted using a pivot language. In this context, it was developed NEPaL (Never-Ending Paraphrase Learner) AMSF system responsible for: (1) extract the internet texts, (2) align the text using a pivot language, (3) rank the candidates according to a classification model and (4) use the knowledge to produce a new classifier model and therefore gain more knowledge restarting the never-ending learning cycle.
Posicionamento em ambientes não estruturados e treinamento de redes neurais utilizando filtros de Kalman
(Universidade Federal de São Carlos, 2016-03-04) Lima, Denis Pereira de; Kato, Edilson Reis Rodrigues; https://lattes.cnpq.br/8517698122676145; https://lattes.cnpq.br/0522306511690493
Kalman filters are rooted in the technical literature, as a way of predicting new states in nonlinear systems providing a recursive solution to the problem of linear optimal filtering. Therefore, 56 years after its discovery, many modifications have been proposed in order to obtain better accuracy and speed. Some of these changes are used in this work; these being the Extended Kalman Filter (EKF), Unscented Kalman Filter (UKF) and Kalman Filter Cubature (CKF). This work , divided into three distinct parts: Implementation / Comparative analysis of prediction of Kalman filters in complex systems (Series), qualitative analysis of the possible uses of the Kalman filter variants for neural network training and position and velocity determination a displaced object on a simulated plane with some trajectories Having these analyzes key role in fostering the studies cited in the scientific literature , proving the possibility of such algorithms and methods are used for positioning in unstructured environments
Potencial de utilização de vinhaça como meio para o cultivo da microalga Chlorella vulgaris : aspectos toxicológicos e microbiológicos
(Universidade Federal de São Carlos, 2016-03-04) Bonini, Monica de Albuquerque; Souza, Clovis Wesley Oliveira de; https://lattes.cnpq.br/0781683628437007; Lombardi, Ana Teresa; https://lattes.cnpq.br/6737850858443813; https://lattes.cnpq.br/5490287339979298
Microalgae have been cultivated worldwide to obtain biomass for various applications. Nonetheless the production costs of microalgae is still high due to factors such as photobioreactors, water and nutrients to grow the organisms. In recent years the use of wastewaters of several origins for microalgal cultures have been studied. However wastewater generally are more complex than synthetic microalgae culture media. Their characteristics can vary over time and have associated microorganisms such as bacteria, fungi and yeasts. Vinasse is a wastewater generated in large volumes by the ethanol industry of Brazil and it is rich in nutrients and organic materials. The use of this effluent to support microalgae growth can reduce the microalgae production costs at the same time that it decreases the contaminant potential of the effluent through the incorporation of nutrients into biomass. The aim of this research was to evaluate the potential of the use of sugarcane vinasse as culture medium for the growth of the freshwater microalgae Chlorella vulgaris. C. vulgaris is a robust species commonly used in the treatment of effluents. Laboratory tests were initially conducted with two distinct vinasses, a conventional and an originating from a agroecological processing, at different concentrations. Based on these results the conventional vinasse was selected for more detailed studies that aimed at treating the vinasse in defined procedures known as Toxicity Identification Evaluation (TIE). Through such procedure, we attempted to answer why it is so difficult to grow microalgae in sugarcane vinasse and how could the microalgal production be increased in such a complex residue. The results showed that pH adjustment resulted in the highest Chlorella vulgaris biomass in vinasse, whereas the addition of EDTA, sodium thiosulfate and XAD-8 resin to remove specific compounds from the wastewater limited the microalgal final yield. The growth of C. vulgaris was higher at intermediate treated vinasse concentrations (30 - 70%). This demonstrated the possibility of using of this residue as a medium for microalgal cultivation. Once selected the ideal condition for C. vulgaris cultivation (30% vinasse and TIE pH=3.0), there was a screening of the microorganisms present in the vinasse and in non axenic cultures of microalgae after its inoculation with C. vulgaris. The microrganisms were isolated and characterized for indole acetic acid (IAA) production, nitrogen fixation and inorganic phosphate solubilization. The presence of heterotrophic microorganisms in the vinasse did not affect the microalgal production. We obtained promising results about future applications of these microorganisms as growth promoters in microalgal cultures. The biomass produced showed protein productivity of 15.57 mg L-1 day-1 and a decrease of nitrogen, sulfate, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC) and total nitrogen (TN) contents in comparison with the initial vinasse was obtained. The results suggest the possibility of using vinasse as a medium for the cultivation of C. vulgaris, with decrease of the potential contaminant of the effluent and increase of biomass production when compared to synthetic culture medium.
Descrição e classificação das expressões cristalizadas com ser e estar do português do Brasil
(Universidade Federal de São Carlos, 2016-03-04) Carneiro, Amanda dos Santos; Vale, Oto Araújo; https://lattes.cnpq.br/2277403284693571; https://lattes.cnpq.br/4858692759066016
This dissertation aims to make a description and classification of frozen expressions of Brazillian's Portuguese that are built with the verbs ser and estar. We consider that frozen expressions are those whose overall meaning cannot be calculated from the sum of the parts that make it up, for example, pé frio in the phrase Leo é pé frio. For this work was adopted the theoretical-methodological perspective of Lexicon-Grammar (GROSS, 1975; GROSS 1981), which is fundamentally based on the Zellig Harris’s transformational grammar (1976). We have analyzed 530 expressions which are divided into eight different classes as distributional regularities. Each class is described in binary tables in which the lines are the expressions and the columns are the syntactic-semantic properties of each input. From the analysis of these classes, we can see a number of regularities showing that such predicates are not an anomaly of the langue. This classification proves helpful also to the Natural Language processing, since the binary tables may be adapted so that computer programs to interpret both the syntactic and semantically correct shape to use as the new searches in corpora.
Modelagem e simulação de células a combustível de etanol direto
(Universidade Federal de São Carlos, 2016-03-04) Maia, Leonardo Kenji Komay; Sousa Júnior, Ruy de; https://lattes.cnpq.br/1983482879541203; https://lattes.cnpq.br/3776047795122736
Two mathematical models of a Direct Ethanol Fuel Cell (DEFC) considering both an ideal (complete ethanol oxidation) and a realistic behavior (partial oxidation with by-products) were implemented in 3D geometries, adapted from SOUSA et al. (2008), using ANSYS CFX. The ideal model considers the cleavage of the C-C bond in the ethanol molecule, leading to a complete oxidation with CO2 and water as products, whereas the realistic model leads to partially oxidized products (acetic acid and acetaldehyde) through a dissociative adsorption mechanism on the catalyst surface. Kinetic parameters of the realistic model were readjusted from the original work (SOUSA et al., 2008) by experimental data fitting in order to calculate surface coverages of the adsorbed species. Model assumptions are: laminar flow, steady-state, isothermal, homogeneous and isotropic porous materials. Analysis of velocity, pressure and concentration profiles were performed in five different anode flow designs: serpentine, double serpentine, parallel, interdigitated and spot. Results have shown that, within the anode flow designs evaluated, the DEFC containing the interdigitated design presented a better performance, measured by the current density vs. cell potential curve. Cell performance was evaluated between anode overpotentials of 0 to 0,5 V. Different inlet velocities were tested to assess how the solution permeates through the porous layers. A qualitative analysis was also performed with a non-isothermal ideal DEFC model to investigate how each anode flow design contributes to heat removal in the fuel cell. Results showed that heat was better removed in the double serpentine and serpentine anode flow designs.
Folheações riemannianas e geodésicas fechadas em orbifolds
(Universidade Federal de São Carlos, 2016-03-04) Souza, Cristiano Augusto de; Barreto, Alexandre Paiva; https://lattes.cnpq.br/3369766702725474; https://lattes.cnpq.br/6843971891313168
The present thesis is devoted to the study of closed geodesics in some types of orbifolds. First, we present the notion of Riemannian foliation and their equivalent definitions using foliation atlas and Riemannian submersions. Aiming to understand the leaf space of certain foliations, we introduce the concept of orbifold. Also, the notion of orbifolds will be addressed via pseudogroups. For compact Riemannian good orbifolds, we will prove the existence of non-trivial closed geodesics. The main objective of this work is to obtain closed geodesics in compact Riemannian orbifolds by employing the shortening process with respect to Riemannian foliations. Following the approach of Alexandrino and Javaloyes [5], we also discuss the existence of closed geodesics in the leaf spaces for some classes of singular Riemannian foliations.
Proposta e aplicação de uma sistemática baseada na gestão do conhecimento para a melhoria do processo de compras públicas
(Universidade Federal de São Carlos, 2016-03-04) Kariyado, Monica Yukie; Amaral, Roniberto Morato do; https://lattes.cnpq.br/6958372164719600; https://lattes.cnpq.br/7236657229614215
The purchasing management plays a strategic role in public organizations, since their function is supply them with inputs, raw materials and services needed to achieve their goals. However, the public procurement processes are highly regulated and bureaucratic, causing disorders affecting the performance of acquisitions. The objective of this research was to propose and implement a system for improving the internal purchasing process in a Federal Institution of Higher Education (IFES) based on Knowledge Management. The research method used was action research and the organization studied was the Federal University of São Carlos (UFSCar). The results comprised the development of a systematic, based on knowledge management, to improve the purchasing process and its application in unit case, which involved four steps: 1] diagnosis of the problem situation: mapping process information flow purchasing, identification of stakeholders, problem causes, the knowledge conversion processes; identification of potential knowledge management initiatives and the selection of operational focus; 2] implementation; 3] Evaluation and 4] solution Replication. The conclusion is based on theoretical discussion and analysis of results that knowledge management can contribute to the improvement of public organizations purchasing process by implementing solutions focused on the actors and the knowledge conversion processes.
Um instrumento psicométrico de coparentalidade: escolha, adaptação transcultural e evidências iniciais de validade interna
(Universidade Federal de São Carlos, 2016-03-04) Carvalho, Thaís Ramos de; Barham, Elizabeth Joan; https://lattes.cnpq.br/9868595523538592; https://lattes.cnpq.br/6843243247683868
Coparenting involves interactions between the mother and father of a child for whom they are jointly responsible. However, when a review of the Brazilian literature was conducted, no studies on the validation of coparenting instruments, for use in Brazil, were found. Thus, the objectives of this study were: (a) compare coparenting instruments described in the international literature, and select the one with the strongest theoretical foundations and the most robust psychometric properties, to adapt for use in Brazil; and (b) compare the Brazilian version of the selected instrument with the original version, to verify their semantic, conceptual, cultural, idiomatic, operational and measurement equivalence. Using a systematic search in electronic databases, 35 articles about the validation of eight coparenting instruments were found. After analyzing the theoretical and psychometric evidence, the Coparenting Relationship Scale (CRS) was chosen, to adapt for use in Brazil. Next, an initial translation of the CRS was revised, using the transcultural adaptation process, leading to the preparation of the Escala da Relação Coparental (ERC). In the final step of this process, individual interviews were conducted with each member of 25 couples, who all had at least one child between 3 and 6 years of age. The participants ranged in age between 24 and 49 years, and the couples earned an average of BRL 6,420.00 (sd = BRL 4,598.54), a month. For each item of the instrument, the participants: (a) indicated the extent to which the behavior being described represented their own coparenting relationship (using a scale of agreement, ranging from 0 to 6); (b) indicated if they believed that these behaviors influenced the quality of the interactions established by couples raising children, and, if so, how positive or negative this impact would be (evaluated using a scale from 1 to 10); and (c) gave examples of situations in which they had behaved in the described way. The levels of internal consistency for the ERC were within the expected range for three of the seven subscales. Average subscale scores were high on the positive dimensions (4.53 to 5.35) and low on the two negative subscales (0.63 and 0.78). Between 76 – 100% of the respondents rated each behavior as positive or negative, in accordance with the structure of the original instrument, and their examples confirmed this. Thus, the results of this study indicate that coparenting is being incorporated into parenting relationships, in Brazil, and that the participants’ perceptions of the ERC are convergent with the structure of the original version. However, the ERC must be tested with a second sample, to verify and resolve possible internal consistency problems, in addition to conducting studies to obtain evidence of the validity of this instrument, based on relationships with external variables. If the ERC can be validated for use in Brazil, it will be useful for evaluating intervention programs that aim to increase parents’ positive interactions, with respect to raising their children.
Diversidade funcional e estratégias nutricionais de espécies arbustivo-arbóreas de cerrado e floresta estacional
(Universidade Federal de São Carlos, 2016-03-04) Miatto, Raquel Carolina; Batalha, Marco Antônio Portugal Luttembarck; https://lattes.cnpq.br/3893228815181339; https://lattes.cnpq.br/3215187098685874
Soil fertility is one of the main determinants of the abrupt boundaries between the cerrado and the seasonal forest. Given that the remaining patches of cerrado are surrounded by agricultural matrices and may be impacted by eutrophication, understanding whether the dystrophic soils of cerrado drive plant strategies and diversity might help us predict the risk of cerrado replacement by forest vegetation and avoid loss of species and functions. In the first chapter, we compared cerrado and seasonal forest species in terms of nitrogen and phosphorus concentration in green and senesced leaves and resorption efficiencies. We quantified the relationships among these traits, with other key leaf traits, and with soil features. Nitrogen and phosphorus concentration in green and senesced leaves were more strongly related to generalised measures of soil fertility than to soil total nitrogen and available phosphorus, but this pattern was not so clear for resorption efficiencies. Besides, leaf nitrogen:phosphorus ratio was lower in cerrado, despite the lack of difference in soil nitrogen and phosphorus between both vegetation types. In the second chapter, we tested whether cerrado and seasonal forest communities were assembled by different processes, despite their physical proximity. We calculated the pairwise functional-phylogenetic distances in cerrado and seasonal forest communities. We tested whether these distances were related to soil properties in each environment. Cerrado and seasonal forest were not assembled by different rules, and soil fertility determined the functional differences between both vegetation types, even though it was not the only force shaping the communities. In the third chapter, we studied patterns in chemical and structural traits in green leaves of cerrado and forest species, in their response to soil fertility, and in their effect on litter decomposition rates. Despite the large effect of taxonomy, soil exerted strong effect through multipleelement control over species functional traits and strategies. The effect of such different strategies on functioning, however, was less prominent.