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Mineração de regras de associação temporais envolvendo dados quantitativos contínuos
(Universidade Federal de São Carlos, 2020-08-07) João, Rafael Stoffalette; Ribeiro, Marcela Xavier; https://lattes.cnpq.br/0300141044144026; https://lattes.cnpq.br/0409203389633082
The consideration of temporality in a explicit manner on the task of association rules mining that involves continuous quantitative data is one approach that aims to contribute to the field of study of knowledge discovery in databases. The construction of temporal intervals from attributes of a data set also provides to the method to identify binary relations, which these intervals may have. This work describes the development of a new method, named ART-Q, for the task of mining temporal association rules which involve continuous quantitative data. The temporality is assumed, in the present work, in its explicit form, not only by data sequencing. The patterns that allow the rules construction are made of binary relations from Allen’s intervalar algebra in the temporal intervals that describe the continuous quantitative attribute’s behavior of interest. The method has proven being able to reveal implicit information in different contexts databases. The results are demonstrated by temporal intervals of interest of the attributes and their algebric relations, patterns and temporal association rules. The work demonstrates that the method ART-Q contributes to the evolution of the literature with the definition and search of a new kind of pattern, more complex than those present in the studies. By the consideration of this kind of patterns association rules are constructed semantically involving a large amount of information among the implication of the rule.
Biomimetism of Brazil nutshell (Bertholletia excelsa)
(Universidade Federal de São Carlos, 2020-08-07) Sônego, Marília; Pessan, Luiz Antonio; https://lattes.cnpq.br/8276650236213537; https://lattes.cnpq.br/3460853436777584
For thousands of years, nature has accumulated countless possibilities for optimized solutions to engineering problems using limited raw material, room temperature, aqueous solutions, solar energy and renewable resources. Recently, this natural accumulated knowledge has increasingly being studied and applied to solve technical problems in studies of biomimicry and bioinspiration.One from many examples are the fruit walls of nuts and drupes which are of special interest for the development of impact and puncture resistant bioinspired structures. This project aims to identify and apply the principles responsible for the excellent mechanical properties of Brazil’s nutshell (Bertholletia excelsa) to develop polymeric composites with superior toughness and mechanical resistance. Firstly, the hierarchical levels of organization of the nutshell structure were identified through chemical analysis, optical microscopy, scanning electron microscopy (SEM) and microtomography (MicroCT). Additionally, the mechanical properties of the nutshell were evaluated in tensile, compression, hardness, and fracture toughness tests, at different length-scales. Moreover, the analysis of fractured surface was carried out by optical microscopy, SEM and MicroCT, identifying the fracture and toughness mechanisms developed by Brazil’s nutshell. Finally, the principles responsible for Brazil’s nutshell mechanical performance were applied to optimize the mechanical performance of a bioinspired polymeric composite. The developed composite is composed of a 3D printed structure of polylactic acid reinforced with 30% of carbon fiber (PLA-30CF) which was impregnated with syntactic foam (epoxy resin and hollow glass microspheres). The mechanical performance of the bioinspired composite is promising. It has density of 0.96 g/cm3, flexural elastic modulus of 2.52 GPa, and impact strength of 1.8 kJ/m2. However, adjustments and improvements in the syntactic foam are still required.
Modificação de filtros de ar condicionado com nanopartículas de cobre com efeito biocida para ambientes indoor rooms
(Universidade Federal de São Carlos, 2020-08-07) Machry, Karine; Aguiar, Mônica Lopes; https://lattes.cnpq.br/0431688649128529; Bernardo, André; https://lattes.cnpq.br/5705402824877708; https://lattes.cnpq.br/8863820504316400
Filter media, as used in air conditioning system, are the first physic barrier between external environment and indoor rooms. To avoid the contamination in indoor rooms, one preventive measure is to contain the proliferation of pathogen microorganisms in filter media. The aim of this work was to do a physical characterization of a polyester commercial filter media, in order to visualize the visual aspect of the fibers and quantify the permeability. Present work aimed to synthesize copper nanoparticles, characterize it and impregnated it to filter media, aiming confer biocidal effect. The copper nanoparticles were synthesized by a redox reactionby two methods: using PVP as the dispersant agent and other one using starch. CuNPs were analyzed in XRD as it chemical composition, and in SEM coupled to EDS system to characterize it physically and chemically, respectively. In the end, the impregnation of the nanoparticles to the polyester fiber was done, one only with CuNP and another one with a pretreatment with HCl. Biological analysis with E. coli and S. aureus was done through the contact method between the bacterial suspension and the filter media. Present work also simulated a prototype of air conditioning in real environment aiming to compare the microbiologic growth in control filter and impregnated with CuNP, simulating an air conditioning system. The composition of both suspensions were a mixture of copper and copper oxide, corroborated with XRD and EDS analysis. The crystallite size was 37 nm to nanoparticles synthesized with PVP, and for those synthesized with starch, the value was 27 nm. Nanoparticles did not have a specific shape and was able to verify that those nanoparticles impregnated to filter media was responsible to the reduction of up to 99,9 % of bacteria. The analysis in real environment was done with the filter with pretreatment done with HCl and impregnated with CuNP synthesized with PVP. It was able to seen that the presence of CuNP in fiber filter showed a biocidal effect when in contact with airborne microorganisms, including fungi. With that, present work showed promisors results to industry, once the indoor air quality it is a public health issue. Several applications can be made with the impregnation of the CuNP to filter medias, including in air filtration of public transports, aviation and even in hospitals applications, as in lab coats, caps and portable air cleaning, aiming to reduce the contamination in those environments.
Aprendizagem de relações arbitrárias em crianças com desenvolvimento típico
(Universidade Federal de São Carlos, 2020-08-07) Kawasaki, Hindira Naomi; Souza, Deisy das Graças de; https://lattes.cnpq.br/4404800720856419; https://lattes.cnpq.br/7461315225130927
Understanding and using socially agreed codes is important for daily tasks. Considering the peculiarities of the learning process of symbolic behavior, which involves control by arbitrary relations among stimuli, it is extremely important to produce knowledge on the characterization of how this process occurs, as well as procedures that facilitate its teaching. This study aimed to characterize the learning process of arbitrary relations in typically developing children between the ages of 3 and 6 years, and also to assess different procedures for the establishment of arbitrary relations and the equivalence classes formation. Two studies were conducted. In Study 1, the learning of arbitrary relations among stimuli of four sets (six stimuli per set) was investigated, through two fading procedures: static and dynamic (Experiment 1). In addition, learning differences in the trial-and-error procedure were also investigated (Experiment 2). Of the twelve children who participated in Experiment 1, six children learned all the relations, two learned the relations for two stimuli sets, one child learned one stimulus set and three children did not show any learning. An inverse relation was observed between age and the amount of exposure to the procedure until the learning relations, independently of the type of fading. In Experiment 2, seven children (among the oldest in Study 1) were exposed to the trial-and-error procedure, and five of the seven children learned all the relations. In Study 2, also conducted in two experiments, the goal was to investigate the learning of simple discrimination with specific compound consequences of classes and the formation of equivalent stimuli classes in young children. In addition to assessing the possible effects of identity matching training (IDMTS) among the members of the composite consequences in the formation of equivalence classes. In Experiment 1, six typically developing children participated. They were ages 4-5 and were distributed in three conditions. All six children learned simple discrimination, but only one demonstrated the emergence of relations in the conditional discrimination probes. In Experiment 2, three other 5-year-old typically developing children participated. The three children learned simple discriminations and showed emergence of conditional relations in most of all probe blocks. In addition, in both studies, for children who tended to demonstrate the emergence of derived relations, differences were observed in the precurrent behaviors and prerequisites for both performing experimental tasks and establishing arbitrary relations. The results clearly indicate the occurrence of relational learning in young children, under certain conditions, and lead to new questions, both from the point of view of basic research and from the point of view of the development and evaluation of teaching conditions that can favor relational learning.
Abordagem investigativa como fator de motivação em três cursos da área de Química de uma instituição pública do Estado de São Paulo
(Universidade Federal de São Carlos, 2020-08-07) Teixeira, Francisco Márcio Barbosa; Ferreira, Luiz Henrique; https://lattes.cnpq.br/4819009378941531; https://lattes.cnpq.br/2202709178357878
Laboratory classes have great potential to motivate students in science courses, whether to learn new knowledge or to demonstrate what they have already learnt. There are some ways of working in the laboratory and two draw attention: the traditional method where the student receives a script ready to develop the practice, and the inquiry approach where, among other characteristics, the student themselves develops their procedure, provided that they have the necessary prior knowledge. In this research, the inquiry approach was applied in three courses in the area of Chemistry at the Instituto Federal de Educação, Ciência e Tecnologia de São Paulo – Campus Capivari: two technical courses and a higher degree in Chemistry. Another important point in this research is motivation, which can be defined as what leads us to perform a certain action. We can be motivated to carry out the actions and the reasons can be internal or external; and if there is no motivation, we will not take the action or do it below our capabilities. That is why the study of motivation is so important in education. One of the theories that have motivation as an object of study is the self-determination theory (SDT), in which it is stated that there are basic psychological needs that are closely linked with intrinsic motivation. In this research we study the motivation of the participating students through the academic motivation scale, and mainly through a semi-structured interview, followed by a textual discourse analysis. The main conclusions were: (i) it was possible to perceive positive changes in meeting the basic psychological needs of students (autonomy, belonging, and competence); (ii) work as an inquiry approach represented a differentiating factor in relation to classes run by the traditional method (prior to the project), according to the students.
Uso de blogs na promoção da argumentação no ensino médio de Química
(Universidade Federal de São Carlos, 2020-08-07) Dias, Fabiane Elidia; Queiroz, Salete Linhares; https://lattes.cnpq.br/7925870606416937; https://lattes.cnpq.br/2694114368216564
In chemistry education, blogs have been used as a pedagogical strategy, enabling students to participate more actively in the teaching and learning process. This research aims to develop and stimulate argumentative practice in high school chemistry classes based on blogs and looking for answers to the following research question: to what extent did the strategy of using blogs help students develop arguments and what can be said about the structural quality of those arguments? In this perspective, four groups of students received instructions to create blogs on the socio-scientific topic of pesticide use. In all the blogs, arguments were verified that present data, justifications and conclusions, which are essential elements, according to the Toulmin Model. Furthermore, in all the analyzed arguments, there is more than one justification that, in most cases, is accompanied by a backing, indicating their good structural quality. Considering the nature of the arguments found in the blogs, the approach to questions about health, environment, economy and social aspects is highlighted. Therefore, setting up the blogs gave the students the opportunity to discuss socio-scientific issues, as well as argumentation based on posting comments.
Processamento convencional e assistido por campo elétrico (Flash Sintering) de cerâmicas livres de chumbo baseadas em K0,5Na0,5NbO3: propriedades físicas finais
(Universidade Federal de São Carlos, 2020-08-07) Zapata, Angélica Maria Mazuera; M'Peko, Jean Claude; https://lattes.cnpq.br/8713770387750524; Zambrano, Michel Venet; https://lattes.cnpq.br/4256279833398263; https://lattes.cnpq.br/7995302836049658
K0,5Na0,5NbO3 (KNN)-based ceramics are considered promising candidates to replace lead-based piezoelectric ceramics, such as Pb(ZrxTi1−x)O3, which are widely used in electro electronic devices. However, obtaining KNN-based ceramics without secondary phases, abnormal grain growth, or problems with partial volatilization of alkali elements represents the main challenge. Therefore, in this work, a study was proposed to optimize the processing conditions of KNN-based ceramics with composition Li0,04(K0,5Na0,5)0,96Nb0,8Ta0,2O3 (LKNNT), both by the conventional sintering as well as by flash sintering method (AC and DC modes). Into synthesis of LKNNT was identified the K3Li2Nb5O15 composition (KLN) as a secondary phase, which causes porosity and low densification (90,8%). However, alternatives as to the addition of 2 wt% excess Li, increasing of the mixing and milling times (24 h), and the use of starting orthorhombic phase Nb2O5, allowed to obtain ceramics without secondary phase, and high densification (97,5%). The synchrotron light measurements in LNLS as a function of temperature showed a morphotropic phase boundary between the orthorhombic and tetragonal phases at room temperature, with a proportion of 19% and 81%, respectively. An anomaly observed at 450 °C in the dielectric permittivity measurements was related to the KNN core-shell microstructures, produced by partial volatilization processes of the alkali elements, compositional inhomogeneity, and the presence of secondary phases. On the other hand, the mechanical and dielectric measurements showed the orthorhombic to tetragonal (TO−T) and the tetragonal to cubic (TT −C) phase transition temperatures around 100 °C and 325 °C for LKNNT, respectively. Flash sintering experiments were performed with the pellet-shaped specimens at 250 - 512 V/cm of electric field and maximum current density of 3 - 20 mA/mm2. The flash event for both KNN and LKNNT was attained around 870 °C. The Partial volatilization processes of alkali elements were observed in the DC mode, followed by the formation of K6Nb10,88O30 and KLN secondary phases. The secondary phases were produced mainly during the sintering process by the reduction and volatilization of Na, causing low densification in the material. Hence, the use of a DC electric field facilitates the formation of the secondary phase in the positive electrode (anode), and a sodium electrochemical reduction in the negative electrode (cathode). However, the use of an AC electric field allowed to obtain KNN at 870 °C for 90 s, without the presence of any secondary phase and with high relative density (94,5%). In the case of LKNNT, a hard electrochemical reaction between the sample and the platinum electrodes led to the breaking of electrical conductivity and low densification. Therefore, were suggested electrochemical processes between the sample and the platinum electrodes during the sintering process to explain the growth of Na2Pt and Li2Pt layers at 900 °C. This reaction causes the formation of an isolated region into the sample-electrode interface, breaking of the electrical conductivity.
Plataformas de TV online: um estudo de caso do Globoplay
(Universidade Federal de São Carlos, 2020-08-07) Albuquerque, Danilo Mecenas Silva; Meleiro, Alessandra; https://lattes.cnpq.br/1295602368246392; Massarolo, João Carlos; https://lattes.cnpq.br/3308336910966465; https://lattes.cnpq.br/9134444046950612
In the era of streaming services, the television concept has been revisited with every new screen device that appears on the market, with an internet connection. Online TV promotes the advancement of television distribution services and differentiates itself from social platforms, like Google, Facebook, Instagram, and LinkedIn, and content platforms, as Netflix and Amazon Prime, among others, by the variety of services that are offered and its closed infrastructure for viewing the audiovisual content collection, selected by algorithms curation. We intend to analyze the notion of Online TV, as a structure that meets the demands of broadcast television, seeking to observe the lines of continuity and ruptures between the Globoplay catalog and the TV grid, seeking to identify the particularities of the services offered by the “native television” platform.