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Vetores Gevrey em estruturas localmente integráveis do tipo tubo
(Universidade Federal de São Carlos, 2014-03-14) Ferra, Igor Ambo; Barostichi, Rafael Fernando; https://lattes.cnpq.br/3582461114222090; https://lattes.cnpq.br/0388427203207282
Técnicas espectroanalíticas aliadas à química verde visando à determinação de V e Mo com procedimentos de extração e pré-concentração
(Universidade Federal de São Carlos, 2014-03-14) Peixoto, Amanda Maria Dantas de Jesus; Pereira Filho, Edenir Rodrigues; https://lattes.cnpq.br/3394181280355442; https://lattes.cnpq.br/0238134456190174
The goal of this PhD thesis was to propose alternatives to improve the analytical performance of F AAS (Flame Atomic Absorption Spectrometry) and LIBS (Laser Induced Breakdown Spectroscopy) aiming V and Mo determination. Some analytical procedures, in agreement with the Green Chemistry principles of, as the cloud point extraction (CPE) and dispersive liquid-liquid microextraction (DLLME) were evaluated in different kind of samples (mineral water, medicines and soil). First was evaluated some parameters concerning to the CPE and the instrumental parameters, using factorial design in order to obtain the better conditions for the extraction of V and Mo individually and simultaneously, as well as the minimum sample volume necessary to introduce in the nebulizer. The limits of detection (LOD) achieved with the CPE to extract individual V and Mo were 80 and 20 μg L-1, respectively. When the CPE procedure was applied for simultaneous extraction, the LODs were 80 and 70 μg L -1 to V and Mo, respectively. The developed procedure was applied in two real samples of medicines and the recoveries obtained were 107 ± 4 % and 98 ± 2 % for V and Mo, respectively. Measurements in presence of Fe (II) (possible interfering) in proportions higher than 1:10 (V: Fe and Mo: Fe) were performed and the absorbance signals of V and Mo decrease thereabout 30 and 50%, respectively. In the second work a procedure employing dispersive liquid-liquid microextraction for the determination of V and Mo by LIBS was developed and applied in water, medicines and soil samples. Some factorial designs were also performed to optimize the best conditions for DLLME procedure. After the optimization, a sample volume of 10 μL was dried in a piece of aluminum foil and submitted to determination by LIBS. The combination of DLLME-LIBS is quite feasible since microextraction is fast, easy to apply, low-cost, they have the possibility of automation, generates little waste and the small volume of the final extract is sufficient for the LIBS analysis. The LOD achieved with the proposed method were 5 and 30 μg L-1 for V and Mo, respectively. The procedure was applied to real samples of two medicines, where the recoveries obtained by comparing with the standard addition method and determination by ICP OES ranged 92-104% for V and 96% for Mo. In the soil sample recovery was 97 ± 15% for V and Mo was below the LOQ and a reference material NCS ZC 85005 (Beef Liver) where V was below the LOQ and the recovery obtained for Mo was 102 ± 21%.
Crenças e motivação em contexto de língua estrangeira para a terceira idade: subsídios para o desenvolvimento de competências do professor
(Universidade Federal de São Carlos, 2014-03-14) Scopinho, Raquel Albano; Viana, Nelson; https://lattes.cnpq.br/6252579012192711; https://lattes.cnpq.br/8317696376557854
The teaching-learning process of a foreign language for the Third Age is a theme that demands attention and has been little explored. Through the investigation of beliefs and motivational aspects in such a context, we intend to provide subsidies for the development of teachers competences, especially the ones who are involved with the referred public. By having in mind that this issue demands knowledge of the real changes that occur during the process of ageing, we have sought support in the fields of Gerontology, Sociology, Psychology and Applied Linguistics itself. The theoretical framework of this thesis was based upon Neri (1991, 1993, 1995, 2000), for the issues related to the Third Age; Dörnyei (1994, 2001, 2005), for the motivational aspects; Barcelos (2001, 2004), for the beliefs, and Almeida Filho (2002, 2005, 2012), for the competences. The research was developed through several instruments such as questionnaires, interviews and self-reports, which involved 110 participants. The analyzed data show us some aspects to be considered in the conduction of the teaching-learning process. We have to consider the single characteristics of the Third Age public, so that we can be aware of the benefits of a social and cognitively exciting environment for the development and maintenance of the elderly physical and mental capacities. However, to achieve this awareness, it is necessary to overcome some possible stereotyped and prejudiced ideas or images of the old people and the old age that are current in society, especially when it refers to the beliefs that old people are not able to acquire a foreign language, that while getting older, we start losing memory gradually and that the elderly do not feel motivated to the acquisition of knowledge or the acquisition of another language anymore.
Otimização estocástica na programação de bombas em redes de abastecimento urbano
(Universidade Federal de São Carlos, 2014-03-14) De La Vega Martinez, Jonathan Justen; Alem Junior, Douglas José; https://lattes.cnpq.br/0744448264150067; Toledo, Franklina Maria Bragion de; http://lattes.cnpq.br/3197500103141618; Toso, Eli Angela Vitor; Oliveira, Fabricio Carlos Pinheiro; http://lattes.cnpq.br/1420326234600531
This study presents a pump scheduling problem for the capture, transfer and storage of water supply systems in urban networks, whose objective is to minimize the electricity cost associated to the pumping operations. To deal with the dynamic and random nature of the water-demand, we propose two-stage stochastic programming with recourse models, where the random variables are represented by a finite and discrete set of realizations or scenarios. The developed mathematical models are extensions of previous deterministic models of the literature and they reflect the basic assumption that a fixed cost could be incurred by the turn on/ turn off activities of the hydraulic pumps. In order to control violations of the water-demand constraints in the presence of multiple different scenarios, we also consider a robustness technique in an attempt to obtain almost feasible solutions. Last, but not least, we adopt a risk-aversion criteria so-called mean absolute deviation to obtain second-stage costs less dependent on the realizations of the scenarios. The scenarios were generated according to a Monte-Carlo simulation procedure that may use any probability distributions to produce the empirical probabilities of the random variables. As the proposed pump scheduling problem with fixed cost is a two-stage stochastic mixed 0 − 1 program, we develop a efficient hybrid heuristic to obtain good-quality solutions of practical instances in a plausible running time. Overall results evidence the stability of the scenario generation method, the sensitivity of the solution according to the key parameters of the mathematical model, and the efficiency of the heuristic in solving large instances. Finally, we show that is possible to save resources by solving the stochastic programming model instead of adopting simpler approaches based on the expected value.
Sexualidade e escolha de objeto na teoria psicanalítica freudiana e nas teorias biológicas do comportamento humano
(Universidade Federal de São Carlos, 2014-03-14) Guarnieri, Silvana; Simanke, Richard Theisen; https://lattes.cnpq.br/5431145327759147; https://lattes.cnpq.br/4526694532478270
Although the relationship between psychoanalysis and biology has been denied by many Freudian followers, today much study has been done in Freud's work, resuming his concepts within the naturalistic bias. Aiming to deepen these relationships, this study aims to analyze the convergences between the psychoanalytic concept of object choice and sociobiological studies regarding choice of partners. For psychoanalysis, human sexuality doesn´t have a main objective to reproduce, but this does not take us away from biological conceptions of sexuality, as is pointed out by several theoretical biology and contrary to a widespread view within the psychoanalytic means. It is thus to analyze how psychoanalysis and biology study this aspect of human sexual behavior, including their specificities, but also looking to evaluate their degree of convergence and complementarity that can then establish
Utilização de condições de contorno para combinação de múltiplos descritores em consultas por similaridade
(Universidade Federal de São Carlos, 2014-03-14) Barroso, Rodrigo Fernandes; Bueno, Renato; https://lattes.cnpq.br/7189857417959804; https://lattes.cnpq.br/6288187829262029
Complex data, like images, face semantic problems in your queries that might compromise results quality. Such problems have their source on the differences found between the semantic interpretation of the data and its low level machine language. In this representation are utilized feature vectors that describe intrinsic characteristics (like color, shape and texture) into qualifying attributes. Analyzing the similarity in complex data, perceives that these intrinsic characteristics complemented the representation of data, as well as is carried out by human perception and for this reason the use of multiple descriptors tend to improve the ability of discrimination data. In this context, another relevant fact is that in a data set, some subsets may present essential specific intrinsic characteristics to better show their rest of the data elements. Based in such premises, this work proposes the use of boundary conditions to identify these subsets and then use the best descriptor combination balancing for each of these, aiming to decrease the existing semantic gap in similarity queries. Throughout the conducted experiments the use of the proposed technique had better results when compared to use individual descriptor using the same boundary conditions and also using descriptors combination for the whole set without the use of boundary conditions.
Carnavalização como transgrediência da multidão
(Universidade Federal de São Carlos, 2014-03-14) Silvestri, Kátia Vanessa Tarantini; Miotello, Valdemir; https://lattes.cnpq.br/9131819326282708; https://lattes.cnpq.br/1544987367343253
Problematize the carnivalesque as a political inorganization a multitude of subjects who transgress power relations is the general aim of the thesis study. Popular demonstrations in societies that emerge are answers to the oppressor s mechanisms and relations of power that the capitalist logic promotes. These popular events appear as everyday ideology through carnivalesque relationships and are problematized, by this reflection, as objects of study. Two cutouts appear as places of observation in order to emphasize the clashes. 1) The street carnivals that reappear in the last ten years in the national and international scene as noted by the media dissemination. 2) The movement known as Carnival Against Capitalism - promoted by individuals from different countries constituting crowds that destabilize power relations. For such thinkers as Bakhtin (2006a, 2010a, 2010b, 2010c, 2011a ) and Negri, Hardt ( 2005a ) are crucial references in this architectural reflection. Some questions guide this study: 1) What can be read as manifestations carnival towards transgredient? 2) How different subjects do carnival? The purpose is specifically from such questions: 1) argue that every day events can carry a valued investment and such investment, disrupts discourses and relations of domination. 2) Affirm the existence of a "collective of a singularity which are not limited to the massive pocket of dough and composes the crowd. 3) Understand the crowd as a grotesque body - tireless and inalienable. Taking for granted the inextricable link between the social situation and the sign key understandings were: 1) There is no cohesive identity, but identities in constant struggle. 2) There is no speech that completely silenced the other, but lives in the discursive struggle linguistic materiality. 3) The carnivalization is a form of activism, a responsive activity. 4) A rule carnival happens as a counterpoint to the official system through various demonstrations and protests, art, music and parties. 5 - A crowd of singularities also has an affirmative view towards transgredient. Their actions may be carnival i.e., responses to ethics rectified. The research methodology is based on the theoretical perspective of Bakhtin's dialogical dialectic - clash of words and against words - which briefly means that the sign is part of a communication system and therefore cannot be separated from the concrete forms of communication, there is no separation between material reality and ideology of the sign, and there is a tense relationship between official and everyday discourses of.
Estimação do tamanho populacional a partir de um modelo de captura-recaptura com heterogeneidade
(Universidade Federal de São Carlos, 2014-03-14) Pezzott, George Lucas Moraes; Salasar, Luis Ernesto Bueno; https://lattes.cnpq.br/5464564215528609; https://lattes.cnpq.br/3716636700188073
In this work, we consider the estimation of the number of errors in a software from a closed population. The process of estimating the population size is based on the capture-recapture method which consists of examining the software, in parallel, by a number of reviewers. The probabilistic model adopted accommodates situations in which reviewers are independent and homogeneous (equally efficient), and each error is an element that is part of a disjoint partition in relation to its detection probability. We propose an iterative process to obtain maximum likelihood estimates in which the EM algorithm is used to the nuisance parameters estimation. The estimates of population parameters were also obtained under the Bayesian approach, in which Monte Carlo on Markov Chains (MCMC) simulations through Gibbs sampling algorithm with insertion of latent variables were used on the conditional posterior distributions. The two approaches were applied to simulated data and in two real data sets from the literature.
Percepções de inclusão social entre idosos usuários e não usuários de serviços destinados à terceira idade
(Universidade Federal de São Carlos, 2014-03-14) Silva, Mônica Ferreira da; Barham, Elizabeth Joan; https://lattes.cnpq.br/9868595523538592; https://lattes.cnpq.br/4986559368099267
A reduction in social contact among the elderly can result in unhealthy social isolation, and an increase in depressive symptoms. To combat this problem, services for the elderly are emerging, but little is yet known about the factors that affect the use of these services and the contribution of these programs to reduce social isolation. On the basis of the literature review, a new instrument was constructed to evaluate the extent to which older people who are engaged in activities outside the family circle feel that these involvements create opportunities to be more active, more competent, meet new people, form new friendships, learn new skills, do something they enjoy, or to do something related to their personal interests. The overall objectives of the current study were to: a) compare the perceptions of users and non-users of services for the elderly, with respect to their perceptions of the adequacy of their opportunities for social contact outside the family, and b) to determine if elderly people with more positive perceptions of these activities also report fewer depressive symptoms. Participants included 60 people aged 65 years or older (15 female and 15 male service users, and 15 female and 15 male non-users), all residing in a small city with approximately 122.000 inhabitants, in the interior of the state of São Paulo, Brazil. All respondents obtained scores equal to or above their cut-off score on the Mini Mental State Examination, such that all participants presented normal cognitive functioning. After signing the consent form, the participants responded to instruments about their financial status, physical and mental health (Brazilian Socioeconomic Criteria, Katz Scale of ADL, the PAQ and the Geriatric Depression Scale). Next, participants rated the extent to which their nonfamily activities meet their needs for social inclusion. The two groups were highly similar with respect to socioeconomic status, education, and functionality levels. The main findings indicate that both users and non-users of services for the elderly reported a high level of satisfaction with their non-family activities. In addition, average ratings of their opportunities for social inclusion were high in both groups, but those who used services for senior citizens had fewer depressive symptoms than those who did not use these services, which is coherent with some other studies that point to the positive effects of attending universities for senior citizens. As such, the primary contribution of this study was to initiate more detailed work, to identify and better understand how to create opportunities for the social inclusion of the elderly.
Otimização inteligente da decomposição de elemento estruturante em morfologia matemática binária
(Universidade Federal de São Carlos, 2014-03-14) Pillon, Paulo Eduardo; Pedrino, Emerson Carlos; https://lattes.cnpq.br/6481363465527189; https://lattes.cnpq.br/2432378935391081
When working with binary images, mathematical morphology provides powerful tools for analyzing them. Along with genetic algorithms, it allows various computational tasks that are performed autonomously. In recent decades, the decomposition of structuring elements has been involved in the morphological operations used to reduce the degree of difficulty imposed by images of larger size implying in the efficiency of the hardware used for the processing of such images. For accelerating this process, this master's project uses MATLAB and Visual Studio as development tools, aiming at developing an efficient algorithm for decomposing the structuring element facilitating a possible hardware implementation with aim of decreasing the time waste in processing those images.
Síntese e propriedades fotocatalíticas de heteroestruturas TiO2/SnO2
(Universidade Federal de São Carlos, 2014-03-14) Mendonça, Vagner Romito de; Oliveira, Cauê Ribeiro de; https://lattes.cnpq.br/5321313558714462; https://lattes.cnpq.br/4270375873948823
Heterostructures, systems containing two dissimilar semiconductors in direct contact, has been applied in heterogeneous photocatalysis due to their electronic properties. This work aimed at studying heterostructures containing metallic oxides. Due to their suitable features, both anatase TiO2 and rutile SnO2 were chosen to compose a model-system. In the first part, this work dealt with the synthesis of TiO2/SnO2 heterostructures by using two different routes: the sol gel hydrolytic (Hid) and the polymeric precursor method (Prec). The heterostructures photocatalytic properties were evaluated by the photodegradation of rhodamine B dye (RhB) under UV radiation. The results showed that heterostructures were more active than pristine TiO2, the same used to make heterostructures. That finding was related to charge migration between oxides, a heterostructure feature, as showed by photoluminescence spectroscopy analysis. The homogeneity in the phase formation (i.e., SnO2 dispersion over TiO2) was influenced by the synthesis method, as showed by X ray diffraction, Raman spectroscopy and scanning electron microscopy with X ray microanalysis. The main RhB degradation mechanism was correlated with the process of OH radical generation, which in turn was related to the concentration and nature of the surface hydroxyl groups on the photocatalyst surface, as determined by infrared spectroscopy analysis. Accordingly, the polymeric precursor method was shown to be more adequate for dispersing higher amounts of SnO2 in comparison with the hydrolytic sol gel method. In the second part, due to the difficulty of a controlling morphology in a one-pot crystallization of two components, and to isolate the effect of charge migration between oxides, it was studied the possibility of obtaining heterostructures from pre formed nanoparticles by an aggregation and coalescence process induced by hydrothermal annealing. Morphologically xiv different oxides were separately synthesized and hydrothermally treated in different conditions. A kinetic model based on a diffusion controlled process was applied in the analysis of results. The ability of generating OH radicals under UV radiation was used to verify the charge migration. The results demonstrated the possibility of obtaining heterostructures by an aggregation followed by a coalescence process. It was also showed the charge migration between oxides, despite the interface being a point of charge recombination. The heterostructure formation was confirmed by comparing the heterostructure capability to generate OH radicals with anatase TiO2, the active phase, when treated in the same hydrothermal conditions.
Propriedades de transporte em óxidos condutores transparentes (TCOs): In2O3, SnO2 e SnO2:F
(Universidade Federal de São Carlos, 2014-03-14) Amorim, Cleber Alexandre de; Chiquito, Adenilson José; https://lattes.cnpq.br/7087360072774314; https://lattes.cnpq.br/2813319640699964
In this work we studied some of the structural features and transport in nanostructured metal oxides synthesized by the vapor -solid mechanism (VS) aiming their application in high performance devices. The structural properties of the used samples [In2O3, SnO2 and SnO2 doped with fluorine (FTO)] were characterized by X-ray diffraction, scanning electron microscopy (SEM) and X- ray dispersive energy spectroscopy (EDX). All these techniques confirmed the monocrystalline character which was obtained by the method used for the synthesis process. Concerning the electronic transport properties, a common property for all samples was detected: the conduction mechanism was the variable range hopping. Invariably, such as mechanism is attributed to the presence of a small degree of electronic disorder in samples but which is not enough to induce the localization of all carriers. As an observable result, samples behaved as semiconductors. Specifically, in In2O3 samples the analysis of temperature dependent resistivity allowed us to determine parameters such as the localization length, also determining the dimensionality of the electronic system. Although not intentionally doped, the samples exhibited an appreciable density of electrons due to the amount of oxygen vacancies. Experiments performed with micro-sized sample, unpublished in literature, provided data on mobility and carrier density and their dependence on temperature, determining the dominant scattering process: for ionized impurities (low temperature) and acoustic phonon (high temperatures). The used approach avoids common errors in extraction of those kinetic parameters using devices like field effect transistors, serving as a versatile platform for the direct investigation of electronic properties in nanoscale materials. Samples of SnO2, monocrystalline and not intentionally doped (but with a little influence of oxygen vacancies) also showed a semiconducting behavior guided by the hopping mechanism in a wide temperature range (60-300 K). The presence of a potential barrier in the samples surface lead us to a detailed analysis of the performance metal-semiconductor (SnO2) junctions which was performed using different approaches: thermionic emission , statistical (Gaussian) distribution of Schottky barriers and a double Schottky barrier model. From these, we obtained a fairly detailed description of system providing parameters such as the barrier height (0B ~ 0,42 eV) and the ideality factor (n ~ 1, 05) comparable to the values obtained under conditions of ultra- high vacuum. These samples were used in field effect transistors that exhibited interesting characteristics for applications such as mobility of 137 cm2/Vs. Finally, FTO samples in which we could act on the doping level were explored. Samples showed a monocrystalline character and again a semiconductor behavior was evidenced by the hopping conduction mechanism. With the introduction of dopants on oxygen sites, devices showed an additional effect when a dispersion of nanobelts was used: a negative temperature resistivity coefficient for T < 15 K. We show that this behavior fits in the theory of weak localization in a system of weak disorder. Devices with a single nanobelt has a much smaller chance to exhibit the same behavior as a function of its dimensions. This result is general as suggested by the data: only the intrinsic disorder contributes to the transport mechanism, while the extrinsic one (the dispersion of nanobelts) not contributes. Finally, field effect transistors were constructed showing better mobility parameters for applications. Another original contribution of this work was the determination of an intrinsic parameter for the different materials which is only estimated by theoretical calculations in the literature: the density of states which should be used as reference in literature.