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Estabilidade em equações de reação e difusão : interação entre difusibilidade e geometria em superfícies de revolução e um problema singularmente perturbado no caso de intersecção das raizes da equação degenerada
(Universidade Federal de São Carlos, 2013-03-07) Sônego, Maicon; Nascimento, Arnaldo Simal do; https://lattes.cnpq.br/6609243657130387; https://lattes.cnpq.br/4425077751075680
In this work we study two distinct problems. The first is a parabolic problem with variable diffusivity on surfaces of revolution. The objective is to find mechanisms of interaction between the diffusivity function and the geometry of the domain ensuring the existence of stationary stable nonconstant solution as well as non-existence. The second is a problem of reaction and diffusion singularly perturbed in the case of intersecting roots of the degenerate equation. We prove the existence and geometric profile of four families of stationary stable non-constant solutions to the parabolic equation. In both problems the main tools used are T-convergence theory and techniques of variational calculus.
Consumo de álcool entre universitários: histórico de violência como risco e religião como fator de proteção
(Universidade Federal de São Carlos, 2013-03-07) Priolo Filho, Sidnei Rinaldo; Williams, Lúcia Cavalcanti de Albuquerque; https://lattes.cnpq.br/6962646759651464; https://lattes.cnpq.br/4997927772311378
Alcohol consumption among College students has been a main concern among different sectors of society around the world. Risk factors associated to this behavior are not clear and more research is needed. The objective of this research is to verify if a history of intrafamilial violence is associated to higher alcohol consumption during College years. Furthermore, analyze if religion has an association with the consumption among this group as well. A review of the literature points out that history of violence is associated with higher alcohol consumption, however few researches were made analyzing polyvictimization and future alcohol consumption. The consequences for children that suffered different forms of victimization are not yet known in full extension. This research tries to fill some of those blanks, for that purpose it used the AUDIT questionnaire adapted with 1452 participants. In that sample alcohol consumption in life had a percent of 93.51% to woman and 93.10% to men. While, the consumption in the last 3 month was 82.04% and 83,74% respectively. The most frequent form of violence was physical (40.99%), the second was exposure to domestic violence (30.60%). A linear regression model was performed and was found and association between having a history of violence and a higher score in alcohol consumption. That association was verified to all forms of violence, including polyvictimization. About religion, results shown that 30.16% of the College students reported do not have a Religion, a higher percentage than that found by the National Census. Participants that do not have a religion present a higher chance to consume alcohol and binge drink. Having a religion may be a protection factor to binge drinking, especially, among evangelical participants.
Propriedades da sílica CTA-MCM-41 contendo metacrilatos e seu emprego na transesterificação de monoéster
(Universidade Federal de São Carlos, 2013-03-07) Araújo, Jailson Arruda de; Cardoso, Dilson; https://lattes.cnpq.br/2462847535959232; https://lattes.cnpq.br/4541573294061168
The search for clean and renewable fuels has aroused great interest in the industry and scientific community with the growing demand for energy. The transesterification reaction of triglycerides is one way of achieving a sustainable fuel and less harmful to the environment. This has encouraged researchers to develop new routes of synthesis of heterogeneous catalysts. The CTA-MCM-41 silica has basic catalytic sites called siloxy (≡SiO-) and may be used in transesterification reactions. Its use in base catalysis has shown promising results, but the reuse reveals extensive loss of activity due to the removal of CTA cations from the channels. The catalyst modification may improve the catalytic stability, in which the insertion of polymeric species together the micelles within the silica is one method studied by our group. Given this perspective, this study aimed at evaluating the modification of the basic catalyst CTA-MCM-41. The polymers encapsulation and ultraviolet irradiation on silicas containing monomer were performed in this study. It was possible to prove by means of small angle X-ray scattering conducted on the emulsion and silicas, the polymeric and monomeric species were inside the micelles causing micellar and silica expansion. The infrared absorption spectroscopy, X-ray diffraction and chemical analysis showed that these species remained inside the micelles after encapsulation. The catalytic evaluation demonstrated that the modified silica with low amounts of monomer added showed improved catalytic stability.
Taxa de atração para equações de reação-difusão com difusão grande localizada
(Universidade Federal de São Carlos, 2013-03-07) Pires, Leonardo; Silva, Karina Schiabel; https://lattes.cnpq.br/2677541143976758; https://lattes.cnpq.br/1872209362721295
In this work we study the nonlinear asymptotical dynamics of a semilinear reactiondiffusion equation of parabolic type, when the diffusion coefficient becomes very large in a subregion Ω0 which is interior to the physical domain Ω. We obtain, under suitable assumptions, that the family of attractors behave continuously with respect to a rate of attraction.
Análise comparativa de diferentes tratamentos para reduzir a deterioração de tomates
(Universidade Federal de São Carlos, 2013-03-07) Rosanova, Aline de Holanda; Ferreira, Maria do Carmo; https://lattes.cnpq.br/7070885875161111; https://lattes.cnpq.br/9989278096493384
Due to their high moisture content, tomatoes have a high metabolic activity that continues even after harvesting, making them a highly perishable vegetable. According to FAO, Brazil is the largest tomato producer in South America and the eighth largest producer in the world. Despite this significant production, rapid fruit deterioration causes a loss of about 40% of this production in post-harvesting operations such as transportation and storage. Recently, new techniques have been tested to increase the shelf life of vegetables, such as the use of high voltage electric fields to produce a modified atmosphere in which the ionization induced by corona discharge contributes to retarding deterioration by mechanisms such as the decreasing respiratory rates, destroying ethylene and producting ozone. Therefore, the objectives of this study were to set up, check and test equipment to carry out experiments to treat different types of fruit and vegetables using electric fields. In this work this system was used for tomatoes and its effectiveness was evaluated by analyzing some measurable quality properties such as loss of mass, changes in skin color, fruit firmness, total titratable acidity (ATT) and soluble solids content (SST). This method was compared to the use of refrigeration to extend the shelf life of this vegetable. An improvement of some measurable quality properties was observed after treating tomatoes cv. Andrea Victory intermittently by applying an electrical field of -1.6 kV/cm followed by storage in climate chamber or using -2.0 kV/cm followed by storage at room temperature, and also after using continuous treatments in tomatoes cv. Paron (-1.9 kV/cm) followed by storage at room temperature. The other measured properties did not indicate benefits of electrical field treatment for preserving the fruit quality. Storage of tomatoes cv. Paron at 15.0 oC and relative humidity of 70% reduced the loss of mass and improved fruit firmness in comparison to the control group, while the storage in a domestic refrigerator reduced the loss of mass and improved the skin color of the vegetables. Concerning the treatment techniques electric fields and refrigeration, a clear advantage of one compared to the other was not identified, since both had a positive effect on at least one property investigated.
Estudo de caso da tutoria virtual da UAB - UFSCAR: análise do processo formativo e atuação
(Universidade Federal de São Carlos, 2013-03-07) Fonseca, Ana Paula Araujo; Reyes, Cláudia Raimundo; https://lattes.cnpq.br/1274752433328441
Online education has opened a new way of organizing the processes of teaching and learning, from the division of teaching duties before accomplished by a single teacher. In Online education, the virtual tutor stands out in teaching process. Although considered central to the process of monitoring and evaluation of student performance, few studies have been dedicated to evaluating training proposals for this category. This paper describes and analyzes a proposed virtual tutor training at the Federal University of São Carlos - UFSCar, partner of the System Open University of Brazil (Universidade Aberta do Brasil UAB). The chosen institution is considered a national reference in the field of tutor training, having served as a model for other partner institutions from UAB. This is a case study from the theoretical framework of Behavior Analysis. The procedure adopted was to: a) record the history of the creation of the proposed formation of virtual tutors UAB-UFSCar, from semi-structured interviews with the team that conceived, b) describe the objectives and strategies of teaching and evaluation planned for one of the editions of the course offered at the institution, c) describe and analyze the performance of one the students of the training course on mentoring during the conduct of the course and his first performance after formed d) establish possible relations between the student performance observed during his first acting as a tutor in a course subject of UAB-UFSCar and the aspects present in the 14th edition of virtual tutoring. The main findings showed that training course in virtual tutoring of UFSCar presents the UAB-training strategies that aim to strengthen the knowledge of the "know about." There is a course unit designed to the practical exercise of the function of tutor, favoring the knowledge of the "know-how". The tutoring models offered by tutors trainers are an important part of the training process, as well as the first entry in the mentoring activity. The participant analyzed demonstrated above average performance during the training course, has made all activities toward the goals proposed by the course. However, when his first role as tutor, his performance did not match the expected, especially when compared to the initial training period. These results suggest that the induction period is crucial for tutors remains in training, being pointed to the importance of creating induction programs that helps the tutor virtual in his functions required in every discipline. The teaching staff, as well as the Supervisor of tutors, gives an important support for planning strategies of monitoring the beginner tutor. Indentify relevant aspects of the training offered through contingency analysis of teaching and learning, can directly assist in the improvement of formative processes of the UAB-UFSCar and indirectly to other institutions. It is suggested that the Behavior Analysis can contribute to the training of the tutor, in that it is concerned to create conditions suitable to teach him how to teach.
As organizações sindicais dos trabalhadores e o processo constituinte 1987-88: um estudo sobre a atuação do DIAP
(Universidade Federal de São Carlos, 2013-03-07) Costa, Lucas Nascimento Ferraz; Noronha, Eduardo Garuti; https://lattes.cnpq.br/6908348693613769; https://lattes.cnpq.br/5825771500862011
The goal of this dissertation is to analyze the performance of the Department of Inter Parliamentary Advisory (Departamento Intersindical de Assessoria Parlamentar) (DIAP) in the constituent process of 1987-88. The organization was able to unify the consensual demands of the working class, uniting in a single project for the Constituent Assembly, the unions of the period, that were divided politically. With this, the DIAP changed the trade union agenda at that time, one of the reasons that explain the success of the "lobby" of working class in the National Constituent Assembly (NCA). In research, we divide the dissertation into two phases of the organization, before and during the Constituent Assembly. Previously, since 1983, when it was created, we analyze the formation process of consensual project, which involved the preparation of technical studies and negotiations with union leaders. When working in the NCA, we analyze the influential "lobby" practiced by DIAP, showing political conflicts faced by the organization at every stage of this process. We understand that DIAP was a central actor in defending the interests of workers, managing to convince the unions of workers, leftist political parties and progressive constituents to act according its design. It was a delicate pact, which was only possible by the peculiarities of the constituent process. The Constituent Assembly has provided the opportunity of "lobbies" to seek important achievements, in approving their interests in constitutional standarts. The DIAP is one of the most important products of this political reality. The support given to the organization to act on behalf of a class is explained by its institutional design, which has adapted to the lack of organization and preparation ahead of the unions of the importance of the constitutional process.