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Modificação química de poli(ácido láctico) com anidrido maleico por processamento reativo
(Universidade Federal de São Carlos, 2014-08-18) Rigolin, Talita Rocha; Bettini, Sílvia Helena Prado; https://lattes.cnpq.br/3687551763124327; https://lattes.cnpq.br/9580513904975670
The chemical modification of PLA with maleic anhydride by reactive processing and the extent of reaction and degradation reactions, were studied. Routes of grafting reaction of maleic anhydride in PLA were evaluated. Dicumyl peroxide (DCP), as initiator, and maleic anhydride (MA) for modification of the PLA, were used. Acidity levels of the compositions were obtained by titration technique of the acid groups and observed an increase in acidity of the modified PLA s, with steep increase in the sample of PLA-g-MA, produced in the presence of DCP. During the PLA modification, with MA, was observed a reduction of 45% in Mn, measured by SEC. In order to analyse the reaction routes, PLA/PBAT blends were produced. Compatibilization of the blend was performed by two ways, one using in situ PLA/PBAT modification and the other using a pre-modified PLA (PLA-g-MA). A blend without MA (PLA/PBAT) was used as reference. In according with the observed mechanical behavior, a synergic effect is observed for PLA-g-MA/PBAT blend, despite low molecular weight of PLA matrix.
Estudo da influência da deformação por cisalhamento extrusão em canal angular e laminação assimétrica nas propriedades mecânicas do alumínio AA 1050
(Universidade Federal de São Carlos, 2014-08-18) Vega, Marcelo Clécio Vargas; Kliauga, Andrea Madeira; https://lattes.cnpq.br/3527528295399928; https://lattes.cnpq.br/6048704190676732; Rubert, José Benaque; http://lattes.cnpq.br/1726311467903505; Schön, Claudio Geraldo; http://lattes.cnpq.br/2631107236461952
It is known that the formability of aluminum alloy AA1050 is not favored when sheets are produced by conventional rolling due to the appearance of intense cube texture {100} <100> after recrystallization heat treatment. The objective of this study was to investigate whether components of shear processes can improve this property. For this work two processes of plastic deformation introducing shear stresses were selected: Equal channel angular extrusion (ECAE) and asymmetric rolling; these processes were compared to conventional rolling. In conventional rolling deformation results mainly compressive stresses. In the ECAE process shear is induced in the intersection of two channels of the same geometry that intersect by an angle  In the asymmetric rolling the shear stress is basically increased due to the speed variation between the rolls. An AA1050 aluminum sheet produced by the twin roll casting process was used in this study. The deformations were performed basically in 4 paths: i) conventional rolling, 70% reduction, ii) ECAE 1-8 passes, iii) ECAE 1-4 passes followed by conventional rolling with reduction of 70% and iv) Asymetric Rolling with reductions 30-50%. The mechanical and microstructural characterization of the deformed state was performed and the formability after annealing heat treatment was studied. ECAE deformation reduced the grain size, which measured by EBSD and transmission electron microscopy yield 1 micrometer. The evolution of equivalent strain compared with the increase of the hardness indicated a grain size stabilization of the grain/cell after four ECAE extrusion passes. After 8 passes the fraction of high angle boundaries exceeded the low-angle boundaries, ie dynamic recrystallization occurred during deformation. The texture after one pass ECAE approached the ideal texture for a 120 ° ECAE die. For deformations with 4 - 8 ECAE passes, the texture evolved into scattering the orientations having the {111} plane parallel to the surface ( fiber), and into the formation of rotated cube {100} <110> and rotated Goss {110} <110> orientations. The conventional rolling after ECAE returned the orientations to typical rolling textures: brass, copper and Goss. Deformation by asymmetric rolling with a difference of tangential velocity of 1.2 imposed shear stress, but it was necessary to decrease the reduction rate from 10% to 5% per pass in order to appreciably modify the texture. Comparing the formability of the deformed material, it was observed that ECAE increased the penetration depth in the Erichsen test, while rolling decreased the Erichsen index. Asymmetric rolling reduced the intensity of texture and destroyed the symmetry of the crystallographic orientations. The asymmetric rolled sample presented better formability than the rolled samples. After annealing, the samples of conventional rolling, with or without ECAE pre - strain, showed typical textures of annealed laminated material with high cube texture type. The  fiber was not stable in the ECAE annealed samples. Although the overall texture intensity remained low, increasing ECAE deformation before heat treatment strengthened the Goss {110} <001> orientation. For the asymmetric rolling the fiber orientations <100>// ND was scattered and both rotated cube and cube orientations were present. The lowest index of planar anisotropy was obtained in the sample annealed after four ECAE passes, representing a lower tendency to fail, This sample also presented an index of penetration in Erichsen testing of the same order of conventionally rolled sheets. It has been shown that both ECA as the asymmetric rolling deformation can significantly modify the texture of deformation and annealing, and improve the characteristics of formability of aluminum alloy 1050. This processing step should be located at the end of mechanical forming process before final annealing.
Identificação e extração semiautomática de contextos definitórios em corpus com vistas à redação da definição terminológica: proposta de sistematização linguística para a língua portuguesa
(Universidade Federal de São Carlos, 2014-08-18) Kamikawachi, Dayse Simon Landim; Almeida, Gladis Maria de Barcellos; https://lattes.cnpq.br/4046789388750478; https://lattes.cnpq.br/7846039422136199
Computational tools in Natural Language Processing (NLP) are essential in handling electronic texts. Some of the resources commonly used are: frequency counters, word lists, keywords, and concordancers. It is noteworthy that this last tool, which terminologists use to view and extract defining contexts for certain terms, is useful in the stage of writing terminological definitions. Depending on the term and corpus size, the list of concordances may exceed a few hundred lines, making the task of defining the term extremely time-consuming. Yet, while concordancers facilitate the task of writing definitions, studies in terminology (ALARCÓN, 2009) and NLP (KLAVANS; MURESAN, 2001) have shown that it is possible to develop linguistic formalism that can be a substrate for the generation or enrichment of a system capable of detecting such contexts. While research in this direction has already been undertaken for English, Spanish, German, and French, among other languagesǡ research on Portuguese needs a more accurate linguistic explanation of defining context, in order to serve as a base for the development of similar systems for the Portuguese language. Therefore, the goals of this research are as follows: 1) to investigate the patterns of defining contexts found in technical corpora in Portuguese, 2) to provide linguistic knowledge which can be formalised computationally to create a system of semi-automatic extraction of candidate defining contexts, and 3) to evaluate the results generated. As the study’s corpus, we used scientific articles from the Bank of Portuguese (LAEL-PUC), and for the analysis, the following verbs were chosen: nomear ‘to name’, conceber ‘to conceive’, chamar ‘to call’, entender ‘to understand’, conhecer ‘to know’ and denominar ‘to denominate’. It was possible to do: 1) a quantitative and qualitative description of each verbal definitory pattern, 2) a local grammar for the chosen verbs with the purpose of aiding in the semiautomatic retrieval of definitory contexts, 3) an exclusion grammar to serve as a stoplist for local grammars and 4) a set of heuristics for a semiautomatic definitory context classifier. The evaluation of the lexical-syntactic rules of these six verbs showed 64% accuracy and 92% coverage in the global average, which represents an optimistic result in comparison to the results of previous studies. As a result, it was possible to 1) validate the methodology used, making it possible to extend it to other lexical-syntactic patterns and 2) obtain linguistic knowledge in order to integrate a semiautomatic computational system for definitory context candidates extraction for the Portuguese language.
O impulso utópico em The Wanting Seed
(Universidade Federal de São Carlos, 2014-08-18) Silva, Débora Heloisa da; Ferreira, Carla Alexandra; https://lattes.cnpq.br/5522506928191940; https://lattes.cnpq.br/6909920465608693
This dissertation seeks to analyze the dystopic novel The Wanting Seed (1962), by the English writer Anthony Burgess with the objective of identifying in which way both structure and the development of the work points to, at an aesthetic level, the global feeling of utopia, which Fredric Jameson (2007) calls utopic desire or utopic impulse, which is present in daily life, in politics, in social movements and revolutions. Through the political reading, this research tries to show that, far beyond a novel about a degenerated future by overpopulation, this book presents, in its formal contradictions, much from the social, political and economic global movement of which it is part.
Investigação sobre o estabelecimento de falsas memórias por meio do paradigma da equivalência de estímulos
(Universidade Federal de São Carlos, 2014-08-18) Aggio, Natalia Maria; Rose, Julio Cesar Coelho de; https://lattes.cnpq.br/3386857761295187; https://lattes.cnpq.br/4553599639534161
False memories are defined as remembering events that never happened or remember facts in a distorted way. In cognitive psychology this phenomenon has been studied through the Deese-Roediger-McDermott (DRM) paradigm, in witch lists of words semanticaly related are used. In behavior analysis, the paradigm of stimulus equivalence is a proposition to study semantic relations. This doctoral dissertation presents three studies with undergraduate students in witch DRM and the stimulus equivalence paradigms were used in association to investigate false memories. First and second studies aimed to replicate the phenomenon in a experimental situations, using both Paradigms. Difference concentrates in the controlled variables. In Study 1, nonsense words were used as stimuli. Procedure was divided into two phases. Phase 1: formation of three twelve members equivalence classes. Phase 2: verification of false memories using lists based on DRM paradigm. A list with 10 out of the 12 stimuli from each of the three classes was presented (study list). After completing a distracter task a lists composed by all stimuli from previously list (targets), the rest of the stimuli form the classes (critical distractors) and four more nonsense words (non-related distracters) were shown. Participants should indicate witch stimuli were presented on study list. Participant recognized significantly more critical distratctors, compared to non-related stimuli. However, results could be due to the novelty of non-related distractors. In the second study, this variable was controlled. In Study 2, bot phases were presented, but in Phase 1, participants were first taught three four-stimuli equivalence classes in witch one set of stimuli was familiar pictures. Later, three classes with twelve stimuli were taught. Stimuli from the first three classes were used as non-related distractors. Participant did not recognized significantly more critical distratctors, compared to non-related. It is argued that results could be due to a weak relations between stimuli from the equivalence classes. The third study aimed to increase the relations between stimuli and to investigate the effect of including emotional stimuli in equivalence classes, on false memories. Study 2 was replicated and in the twelve-member classes, a set of stimuli was pictures with happiness, angry or neutrality expressions. Only in neutral list critical ditractors were recognized significantly more than non-related distractors. Results indicates list with emotions are less likely to produce false memories.
Portal transmídia mundo do sítio: análise do projeto transmídia do Sítio do Picapau Amarelo e sua relação com as demais extensões da obra de Monteiro Lobato
(Universidade Federal de São Carlos, 2014-08-18) Torres, Rubens Francisco; Gamo, Alessandro Constantino; https://lattes.cnpq.br/8208629144314123; https://lattes.cnpq.br/9242730746663067
Important Brazilian children's literature author, Monteiro Lobato created with his books of "Sítio do Picapau Amarelo" a universe that remains and influences the imaginary of Brazilian population until today. This universe is not restricted only to literature, it expanded also in other media over almost ninety years, through TV shows, comic books, movies, and other media. In 2011 became available online the portal "Mundo do Sítio", first transmedia project product based on the work of Lobato. Besides the portal, the design transmedia of the "Sítio" also features an animation, social networking pages and a physical themed space located in Mairiporã-SP. The present research attempts to identify how the current transmedia project was developed from a universe already known and how it leverages influences from other adaptations to reintroduce the "Sítio" to a new generation. To do this, we conducted initially a historical survey of all the productions with the brand of the "Sítio", since the publication of the books by Monteiro Lobato, and then, we analyze the portal and identify its main transmedia characteristics and their relationship with the other productions made with the brand. Transmedia design of the "Sítio" uses elements developed in other adaptations of the work of Lobato and continues the expansion of the fictional universe, re-creating your space and encouraging their users to experience a playful way of that universe. With the animation, the story is expanded; presenting new information about the universe without mischaracterize the main characteristics developed by Lobato. Through social networks, users participate actively, both to assess the functioning of the Portal and how to develop productions based on the universe of the "Sítio". Finally, the portal uses features present in the text of Lobato that work effectively in the development of a TransMedia narrative.