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Estimadores não paramétricos para dados com censura
(Universidade Federal de São Carlos, 2013-04-19) Simioni, Paulo Ricardo; Campos, Adriano Polpo de; https://lattes.cnpq.br/4867996651212204; https://lattes.cnpq.br/6532783408466109
In this paper we study the reliability of systems with connected components in series and parallel. For systems in series, the device fails when the first component fails. Although in the parallel systems this happens when the last component fails. We define the distribution functions, sub-distribution functions and their respective properties. Here we present the Bayesian nonparametric estimator for the components of both systems, illustrating by examples. For both cases we performed a comparative study between the Bayesian nonparametric estimator and the Kaplan-Meier method.
Crenças sobre a língua espanhola para estudantes brasileiros do ensino fundamental: características e uma proposta de encaminhamento
(Universidade Federal de São Carlos, 2013-04-19) Raizer, Paula Barros; Yokota, Rosa; https://lattes.cnpq.br/9230517686993400; https://lattes.cnpq.br/7157709550260372
Taking into account the classroom context, it is necessary to know and to comprehend the previous knowledge brought by students. The beliefs concept (BARCELOS, 1995) is recurring to try to understand this context and to help teachers to deal with the diversity they can find in the classroom and, according to Almeida Filho (1993), beliefs are fundamental parts in the process of learning a language, named by him as “Operação Global de Ensino de Línguas”. Considering the Spanish Language implantation at public schools, according to the law 11.161/05, it is necessary the study about the beliefs which future learners have about Spanish language. Likewise, this study has as a first goal to identify the beliefs about Spanish language learning and teaching in a group of people who participate in a Spanish language course at a public school. This course was offered by the Programa Institucional de Bolsa de Iniciação à Docência (PIBID)/ Capes at a school in the interior of São Paulo state. Also as a goal, it is intended to verify whether beliefs changes happened during the course as well as whether the courses influenced on it. Taking into account the contextual approach of beliefs, at the beginning of the course it was applied a questionnaire in “Likert Scale” (HORWITZ, 1988). During the course, it was asked for them to write diaries and, in the end, they wrote a text, in such a way that beliefs could be mapped, as well as possible changes. The results obtained reveal beliefs that Spanish was a difficult language to be studied and it changed at the moment students got in touch with the language, what also elucidates the pronunciation appreciation to the detriment of writing and the interest of students in having Spanish as an obligatory subject. In the end, it was propounded the critical literacy view as a way of dealing with beliefs in the classroom, since critical literacy is one educational practice which focuses on the relation between language and worldview, social practices, power, identity, citizenship, intercultural relations and globalization/location aspects (MATTOS, 2011).
Estudo do desempenho de eletrodos de dióxido de chumbo depositados sobre diferentes substratos para o tratamento eletroquímico de soluções contendo corantes têxteis
(Universidade Federal de São Carlos, 2013-04-19) Irikura, Kallyni; Bocchi, Nerilso; https://lattes.cnpq.br/5930614700886481; https://lattes.cnpq.br/0942777236443310
PbO2 films were grown galvanostatically on different substrates (titanium Ti, platinized titanium Ti- Pt and carbon fiber CF) and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and linear potential sweep in H2SO4. SEM micrographs revealed the growth of PbO2 films well distributed, uniform and compact. The diffractograms presented the formation of PbO2 films of a single phase (β -PbO2). From the potential sweep (30 mV s 1), the overpotential values for the OER of Ti/β- PbO2, Ti-Pt/β -PbO2 and CF/β-PbO2 electrodes were obtained, respectively: 2.15 V; 2.20 V and 2.33 V vs. SCE. The electrochemical performance of these electrodes was investigated in electrooxidations of solutions containing the dyes acid green 28 (AG 28) and yellow direct 12 (YD 12), employing a reactor filter-press type and the experimental design methodology by varying the following experimental parameters: pH, current density (j), temperature (Θ) and NaCl concentration ([NaCl]). For AG 28 dye, the Ti-Pt/β-PbO2 and Ti/β-PbO2 electrodes presented the lowest values of charge for color removal (Q90 ~0.5 A h L 1) and the highest values of % COD removal (87 99 %) in the following experimental conditions: pH = 5, j = 50 mA cm-2, Θ= 25 ºC and [NaCl] = 1.5 g L 1, while the CF/β-PbO2 electrode presented the lowest Q90 value (0.20 A h L 1) and the highest % COD value (86%) in the following experimental conditions: pH = 9, j = 30 mA cm-2, Θ= 45 ºC and [NaCl] = 1.5 g L 1. The β-PbO2 films grown on Ti and Ti-Pt exhibited chemical stability ([Pb2+] < 0.5 mg L 1) in solutions of pH > 3, while those grown on FC showed chemical stability only at pH 9. For the YD 12, the Ti-Pt/β-PbO2 and Ti/β-PbO2 electrodes presented the lowest Q90 values (0.57 0.68 A h L 1) and the highest % COD values (96 100 %) in the following experimental conditions: pH = 5, j = 30 mA cm 2, Θ= 45 ºC and [NaCl] = 1.5 g L 1. Comparing the performance of Ti-Pt/β-PbO2 and Ti/β-PbO2 electrodes with that of commercial ones of Nb/BDD and DSA, the first presented, for the AG 28 dye, better performance than the DSA and comparable to the Nb/BDD. In the case of the AD 12 dye, the Ti-Pt/β-PbO2 and Ti/β-PbO2 electrodes showed performance comparable to the DSA and lower than the Nb/BDD.
No labirinto da gestão: notas sobre moradores de rua e trabalhadores da assistência social
(Universidade Federal de São Carlos, 2013-04-19) Pereira, Luiz Fernando de Paula; Rizek, Cibele Saliba; https://lattes.cnpq.br/1903375661827033
Cette thèse porte sur la gestion des sans domicile fixe en dehors des contextes métropolitains ou des grands centres urbains. Elle vise l‟analyse des mécanismes qui affectent à la fois les sans domicilie fixe assistés, que les professionnels qui travaillent dans les institutions, en interrogeant l‟action de l‟État. L'enquête a été menée dans deux institutions d‟accueil des sans domicile fixe à São Carlos/SP-Brésil: un Centre de Référence Spécialisé dans la Protection Sociale: accueil de la population des sans domile fixe (CREAS -POP) et SOS Auberge de Nuit Santa Isabel. L‟analyse mobilise notamment l‟approche de Michel Foucault, en particulier les catégories des dispositifs, des rapports de pouvoir et de la population. D‟après notre hypothèse générale, le processus de transformation des sans domicile fixe en usagers des services de l'aide sociale a des effets non prévus par l‟institution. Dans ce sens, il y a une diversité de pratiques qui peuvent être interprétées en termes de rapports de pouvoir, y compris des formes de résistance des usagers comme des professionnels qui composent, transforment et remodèlent le dispositif d'assistance sociale . Cependant, l‟analyse porte aux processus qui impliquent les professionnels et les gestionnaires des services aussi. L‟objectif de la recherche est d‟analyser un certain nombre de situations qui permettent de saisir des gestes, croyances, conduites, ressentiments, prescriptions qui correspondent à des perspectives spécifiques en interaction, pour en saisir les tensions sous-jacentes. La proposition est de traiter des questions qui ne sont pas faciles à comprendre et qui ont peu de recherches.
Zirconato de cálcio: um estudo para aplicação como sensor de umidade relativa
(Universidade Federal de São Carlos, 2013-04-19) Andre, Rafaela da Silveira; Longo, Elson; https://lattes.cnpq.br/9848311210578810; https://lattes.cnpq.br/4843978824084924
In this work, it was used the Polymeric Precursors method (PPM). It started from a previous solution of metal cations in different concentrations, using citric acid as chelating agent and ethylene glycol as esterifying and polymerizing agent resulting in a dense resin. This resin was subjected to heat treatment at 300 ° C for a period of 4 hours for the pyrolysis of the obtained polyester resulting in amorphous compound. To obtain the crystalline powder, the amorphous compound was treated at different temperatures. The evolution of the crystallization process of CaZrO 3 and samples composition were accompanied by X-ray diffraction and Raman spectroscopy. The X-ray patterns obtained were refined with the Rietveld method. To identify the presence of defects and the morphology of the samples, it was used the UV-vis spectroscopy and scanning electron microscopy, respectively. To evaluate the sensor response, electrical measurements were performed showing that all samples showed CZO variation of electrical resistance against change in relative humidity. The methods of characterization showed structural differences in the samples as a function of composition variation of the system. The results indicate a transition from deep defects to light defects, due to the appearance of secondary phases in the system. Thus, according to the obtained results, the variation in composition may be used as a device to obtain materials with controlled optical properties and a more effective sensing and catalytic properties.