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Pensamento computacional, pensamento teórico e currículo escolar à luz da teoria histórico-cultural
(Universidade Federal de São Carlos, 2024-07-30) Mattos, Francielle de; Mello, Maria Aparecida; https://lattes.cnpq.br/8338726751746542; https://orcid.org/0000-0003-2404-7957; https://lattes.cnpq.br/2292116311910266; https://orcid.org/0000-0001-5274-6099
Computational Thinking, as one of the themes of the document Computing Complement to the BNCC, aims to develop cognitive skills related to problem-solving in a structured and systematic way and to develop thinking through computation. Throughout this text, the research, of a theoretical and bibliographical nature, based on the studies of Vigotsky, Davidov, Leontiev, Tikhomirov, the study explored several perspectives on the concept of Computational Thinking (CT). This term has undergone several reformulations with the aim of contributing to the updating of the curricula of courses in the area of Computing in higher education and to the organization of the teaching of these contents in Basic Education. From this, emphasis was placed on its teaching in Early Childhood Education, especially in Preschool, and in the first two years of Elementary School. Thus, it sought to answer the following question: Is computational thinking, as proposed in the BNCC and in its complement in the Preschool phase and in the first two years of Elementary School, towards the development of students' theoretical thinking as proposed by the Historical-Cultural Theory? Thus, the main objective was to characterize and analyze the understanding of computational thinking from the perspective of the Historical-Cultural Theory, as presented in the document Computing: Complement to the BNCC, in the stages of early childhood education (preschool phase) and in the first two years of Elementary School. Having pointed this out, the thesis presents that computational thinking as mentioned in the official documents analyzed is not characterized as theoretical thinking, according to the Historical-Cultural Theory. To this end, the logical-historical movement of the concept “computational thinking” was discussed and subsequently in-depth studies on the need for its formalization and conceptualization were carried out. The analyses led to the elaboration of an integrative synthesis, which guides the formation of theoretical thinking in an articulated manner and resignifies the concepts of Computational Thinking in light of the Theory of Reorganization through Human-Computer Interaction. The results of the research indicated that the term “Computational Thinking”, as presented in the official documents BNCC and Computing: Complement to the BNCC, is not characterized as theoretical thinking according to the Historical-Cultural Theory. In conclusion, it was understood that these documents do not promote the principles of dialectical logic but emphasize "know-how" — skills and competencies — to the detriment of the development of concepts and the formation of theoretical thought.
Qualidade do leite e efeito do processamento sobre a segurança microbiológica do Queijo Porungo
(Universidade Federal de São Carlos, 2024-07-30) Cardoso, Maria Luiza; Pimentel Filho, Natan de Jesus; https://lattes.cnpq.br/9157232954010211; https://lattes.cnpq.br/5730405531015391
Porungo is a traditional artisanal cheese produced in the southwestern region of São Paulo state. Although the milk used in its production is not thermally treated, which could pose a risk of pathogen contamination, the curd undergoes a hot water stretching process. This study aimed to evaluate the quality of the raw milk used in the production of Porungo cheese, as well as the impact of processing on the contaminating microbiota. Milk samples were collected from seven cows at a Porungo cheese production unit and analyzed for somatic cell count (SCC), standard plate count (SPC), total coliforms, Escherichia coli, enterobacteria, molds and yeasts, Staphylococcus aureus, and Streptococcus spp., as well as chemical composition. Over the course of a year, samples of milk, fermented-whey, curd, cheese post-stretching, and cheese post-salting were collected and evaluated for aerobic mesophilic bacteria, total and thermotolerant coliforms, and S. aureus counts. Additionally, the effect of stretching in hot water at temperatures between 65 and 72 °C on the viability of Listeria innocua inoculated into the Porungo cheese curd was evaluated. Three of the seven cows evaluated had SCC levels above 400,000 SC/mL, with S. aureus detected at levels exceeding 3 log CFU/mL in all milk samples, indicating the presence of subclinical mastitis in some animals. All raw milk samples freshly collected had SPC levels below 4.5 log CFU/mL, while fat and total solids content were extremely low. Aerobic mesophilic bacteria and S. aureus counts were not influenced by the season but showed significant differences among the cheese processing stages. Although the stretching stage did not significantly reduce the microbial population in both groups evaluated, a significant reduction was observed in the cheese after salting. The total coliform population varied throughout the evaluation period and among the stages analyzed, with no samples showing contamination by thermotolerant coliforms. The stretching process reduced L. innocua contamination by more than 1 log CFU/g in the cheese curd. Therefore, it can be concluded that, in general, the microbial population is not significantly affected by the time-temperature combination used in the cheese stretching process (65 °C for 2 min). On the other hand, L. innocua showed sensitivity to the stretching process. Thus, low contamination levels in the cheese must be ensured by good milking practices combined with good manufacturing practices.
Aumento da resistência à corrosão por refusão a laser do aço 316L
(Universidade Federal de São Carlos, 2024-07-30) Cruz, Ana Larissa Soares; Gargarella, Piter; https://lattes.cnpq.br/4641435644243916; https://orcid.org/0000-0003-4445-5819; Koga, Guilherme Yuuki; https://lattes.cnpq.br/0933095081175012; https://orcid.org/0000-0003-0792-1139; https://lattes.cnpq.br/8948387799925330; https://orcid.org/0000-0002-3033-2263; Rovere, Carlos Alberto Della; Fogagnolo, João Batista; https://lattes.cnpq.br/8141224513975606; https://lattes.cnpq.br/0548477441275437; https://orcid.org/0000-0003-1534-0561; https://orcid.org/0000-0001-6224-2898
Austenitic stainless steels (ASS), notably AISI 316L, are recognized for their combination of high mechanical strength, toughness, and corrosion resistance in various applications. However, the presence of manganese sulfide (MnS) in AISI 316L stands out as the main cause of pitting corrosion susceptibility. Since electrochemical corrosion is a surface-initiated process, LASER surface remelting (LSR) can be a quick and effective method for eliminating these inclusions, given the process characteristics: high energy density and high heating and cooling rates. This study aims to recover AISI 316L steel compromised by MnS using LSR. The conditions as received and after laser remelting with different energy densities were microstructurally characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. Additionally, the degree of sensitization (ISO 12732) and chloride-induced corrosion resistance were evaluated, the latter investigated by cyclic potentiodynamic polarization, electrochemical impedance spectroscopy, and inductively coupled plasma mass spectrometry in 0.6 M NaCl solution. XPS analyses were conducted for further characterization of the generated films. Power levels of 150 W and 300 W at an energy density of 2000 J/cm² were found to effectively modify and solubilize coarse and acicular MnS inclusions, resulting in a refined and homogeneous microstructure. The remelted samples exhibit a thick and uniform passive layer rich in Cr₂O₃, with high resistivity values (ρδ), indicating superior electrochemical performance. The results highlight the synergistic effects of higher energy densities and power levels in restoring surface corrosion resistance, enabling the formation of more protective and uniform passive films.
Contribuições do ensino bilíngue Libras/Português para a aquisição da linguagem
(Universidade Federal de São Carlos, 2024-07-30) Isidoro, Jayni Roberta Ramos; Rubio, Cássio Florêncio; https://lattes.cnpq.br/8357993415342241; https://orcid.org/0000-0002-6986-1381; https://lattes.cnpq.br/7109381002780237
In this research, we will address the impacts of bilingual education with the inclusion of Libras alongside Portuguese, both for deaf and hearing individuals, and we will examine the influence of this type of education on linguistic acquisition and development. Based on theoretical references, such as Martins (2007) and Gouveia (2019), among others, we carried out a bibliographic analysis of authors who have already experienced bilingual education between sign language and oral language. The results point out, among other issues, a broader lexicon among hearing individuals who went through bilingual education compared to those who experienced monolingual education. Based on this finding, it is concluded that the bilingual oral language/sign language proposal is not only beneficial to deaf children, but also to hearing children.
Fotocatalisadores modificados baseados em PHI para oxidação do álcool alílico para ácido acrílico
(Universidade Federal de São Carlos, 2024-07-30) Costa, Danielly Tamires da Silva; Teixeira, Ivo Freitas; https://lattes.cnpq.br/9782517948999001; https://orcid.org/0000-0002-4356-061X; https://lattes.cnpq.br/4070759896367717; https://orcid.org/0000-0003-4955-1076
The production of plastics in the petrochemical industry significantly contributes to greenhouse gas (GHG) emissions, being responsible for 17% of global industrial emissions. In contrast, biomass, when used sustainably, is carbon-neutral because the carbon released during its combustion is used by plants in the photosynthesis process. Carbon nitrides are known as photocatalysts capable of promoting the oxidation of alcohols, including the conversion of aromatic alcohols to carboxylic acids under controlled conditions. However, the photooxidation of allyl alcohol to acrylic acid using carbon nitrides as catalysts has never been reported in the literature. In this study, we investigate the oxidation of allyl alcohol to produce acrylic acid using H-PHI, a crystalline carbon nitride with potential applications in oxidative reactions. The synthesis of the photocatalyst, based on crystalline carbon nitrides of the type (poly (heptazine imide) sodium (Na-PHI) followed procedures well reported in the literature. A series of catalysts with different degrees of protonation (H-PHI) were synthesized via controlled protonation of Na-PHI. The obtained catalysts were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR) and UV-spectroscopy. These catalysts were tested in photooxidation reactions of allyl alcohol to acrylic acid. Different variations in the reaction medium were explored, including solvent, amount of catalyst, and oxygen pressure as the oxidizing agent. These catalysts not only achieved high efficiency in conversion but also maintained excellent selectivity for the desired product. H- PHI catalysts proved to be more efficient than metal-doped PHI-based catalysts. Therefore, the results obtained demonstrate that protonated carbon nitrides (H-PHI) are a highly efficient and sustainable alternative to traditional catalysts, such as Mo8V2WOδ/SBA-15. Additionally, they are efficient at room temperature and low pressures. Our results indicate up to 100% selectivity for acrylic acid and 70% conversion using water as a solvent at room temperature.
Simulação computacional da prensagem de pós para a previsão de falhas em compactos verdes
(Universidade Federal de São Carlos, 2024-07-30) Furlan, Matheus; Sciuti, Vinicius Fiocco; https://lattes.cnpq.br/0230261917656691; https://orcid.org/0000-0002-3709-3189; Canto, Rodrigo Bresciani; https://lattes.cnpq.br/1316268411830615; https://orcid.org/0000-0002-9286-9912; https://lattes.cnpq.br/3279784895710648; https://orcid.org/0000-0002-5995-5958
Numerical simulation is a powerful tool for reducing production costs and improving dimensional tolerance and mechanical properties of parts produced by powder pressing. The prediction of mechanical properties in green compacts, during and after compaction, is crucial for ensuring part integrity in subsequent processes, such as green machining and sintering. However, failure prediction in green compacts is a field yet to be explored. Additionally, the constitutive models used to represent the mechanical behavior of the powder calls for various calibration procedures. In this context, this project aims to explore the use of experimental procedures and numerical simulations to predict failures in green compacts. To do so, closed-die pressing tests were conducted using an instrumented die equipped with strain gauges, pistons with axial sensors, an axial load cell, and an LVDT sensor. The experimental signals were compared with their numerical counterparts to adjust the parameters of the Drucker-Prager/Cap (DPC) constitutive model, based on parameters obtained from the literature. Two materials were evaluated: alumina powder and PTFE powder. After these adjustments, rubber multiaxial pressing (RMP) tests were planned via numerical simulations, aiming at a geometry/condition in which pinching of the elastomeric mold occurs on the green compact. Experimentally, fractures were observed for both materials. By post-processing the simulation results of these RMP tests, it was possible to validate the DPC model as an indicator of the failures observed experimentally, despite the model's development for simulating material consolidation. The agreement was higher for greater pressure and density levels, and for alumina powder. Thus, the use of DPC models during pressing simulations may provide valuable information about certain conditions and regions that might experience failure, which can be directly applied to rubber mold projects for isostatic pressing and rubber multiaxial pressing.
Estudo da viabilidade da determinação da dissolução em meio aquoso de compostos óxidos utilizando a ferramenta open source orange data mining
(Universidade Federal de São Carlos, 2024-07-30) Santos, Armando José de Sá; Andreeta, Marcello Rubens Barsi; https://lattes.cnpq.br/7904227795652627; https://lattes.cnpq.br/6286321140581380; https://orcid.org/0000-0001-8242-6571
Solubility, or the ability of a material to dissolve in a solvent, is a fundamental property of materials, especially for ceramics and glass. The complexity of solute-solvent interactions makes it difficult to accurately calculate solubility, and the lack of precise measurement methods can affect the reliability of the data. The dissolution rate, which is the speed at which a solute dissolve, is crucial in areas such as chemistry and pharmacology. The Noyes-Whitney equation, developed in 1897, describes how the dissolution rate is influenced by various factors. The chemical composition of a glass can significantly influences its properties, including solubility and dissolution rate. Data mining and machine learning can be used to predict these properties, assisting in the discovery and design of new materials. Neural Networks are particularly useful for predicting solubility and dissolution rate due to their ability to model complex relationships. Orange Data Mining is a data mining and machine learning tool that can be used to predict the solubility and dissolution rate of glasses based on their composition. The tool is intuitive and easy to use, allowing researchers to build models without the need for extensive coding. It is also capable of handling large data sets, essential for data mining, proposing a unified approach to predict both solubility and dissolution rate, using only the material composition as input. This simplifies the prediction process, making it more accessible and less dependent on complex data. In this work, through open-source software, a study of the feasibility of using this tool in predicting solubility and dissolution rate in aqueous medium applied to oxide compounds will be presented.
Análise do ensino-aprendizagem de alunos do ensino médio usando a sequência didática “Os passeios aleatórios do Homem de Ferro”
(Universidade Federal de São Carlos, 2024-07-30) Campos, Guilherme Augusto Silvestre de; Venezuela, Antonio Luis; https://lattes.cnpq.br/8722224671269332; https://lattes.cnpq.br/1926207057247440
In this work, through the McNemar Test and the proficiency test, we show the student's level of learning through a didactic sequence based on “Mônica's Random Walks” which for us was adapted to “Iron Man's Random Walks” with students from high school at a public school in the city of Sorocaba. The proposal for the didactic sequence was developed based on the theoretical foundation of didactic engineering, in which the working steps during the process were divided into theoretical and practical experiments, where students had to answer two nine-question questionnaires before and after the didactic sequence, which were tabulated and analyzed using the McNemar test. The test brought us a measurement of the student's learning, which could be, does not apply or applies, but it leaves a certain doubt, as it did not consider low variations, for this reason we created a percentage proficiency test so that it was possible a visualization by segments and thus have more data and information to carry out the necessary comparisons. Therefore, we would be able to measure through the comparisons proposed by both the McNemar test and the proficiency test how much the student was or was not able to learn the pre-established concepts in this proposal.
Desenvolvimento de processos cromatográficos empregando ensaios de triagem e modelagem fenomenológica
(Universidade Federal de São Carlos, 2024-07-30) Vieira, Felipe; Pádua, Thiago de; https://lattes.cnpq.br/8909812973749651; https://orcid.org/0000-0003-0694-6991; Ribeiro, Marcelo; https://lattes.cnpq.br/0381402687491195; https://orcid.org/0000-0001-5836-3478; https://lattes.cnpq.br/3197311040868687; https://orcid.org/0009-0004-1151-3343
Phenomenological models are valuable tools for developing chromatography methods. However, its applicability is impaired by the theorical complexity and accessibility to model parameters. Despite materials are usually select by screening protocols, data obtained during this phase are not used further in the development of the purification process. Here, a joint estimation procedure that integrates data from microplate screening with a single column experiment was proposed to estimate equilibrium and dispersion parameters for modeling gradient elution. Initial estimates of equilibrium isotherm parameters were derived from the screening data, which were then refined by incorporating column chromatogram data to estimate mass transport parameters and enhance isotherm predictions. The proposed method was validated with a reverse phase chromatography using a non-ionic surfactant and functionalized silica. The equilibrium parameters estimated with microplate data predicted a retention volume 8.9% far from experimental results, while the joint estimation prediction was 0.8% in the best-case scenario. In this case, results show that the use of screening data combined with an L-curve method effectively mitigated model overfitting, even when relying on a single gradient elution column assay. The presented protocol should speed up the process development and reduce the consumption of inputs with column experiments.
Novos desenvolvimentos para dados de contagem
(Universidade Federal de São Carlos, 2024-07-30) Santos, Naiara Caroline Aparecido dos; Lemonte, Artur José; https://lattes.cnpq.br/4283549028869521; https://orcid.org/0000-0002-0249-7474; Bazán Guzmán, Jorge Luis; https://lattes.cnpq.br/8040998023074358; https://orcid.org/0000-0003-3918-8795; https://lattes.cnpq.br/2561367899894135; https://orcid.org/0000-0002-6985-6208
This work investigates new developments in count data analysis, focusing on two methodologies: Item Response Theory (IRT) models and Generalized Linear Mixed Models (GLMM). The research focuses on the development and application of classical and Bayesian methods to improve the analysis of existing count models and to propose new models. The chapters of this thesis comprise manuscripts developed throughout the doctoral program. First, a study is presented with the Rasch Poisson count model, already existing in the literature, aiming at a better understanding and introducing a new approach through the method of nested and integrated Laplace approximations. Techniques for residual analysis are shown through graphical visualization, using randomized quantile residuals, and the methodology is applied in the field of Psychology. We explore alternative models for count responses, which overcome some of the limitations of the Rasch-Poisson model. We detail its formulation and estimation methods, under both Classical and Bayesian approaches. Additionally, we demonstrate the potential of residual analysis using graphs applied to data from an attention test. Next, when considering mixed models, we introduce a new proposal for count responses, based on the one-parameter Bell distribution, explicitly detailing its formulation and estimation under Classical and Bayesian approaches. We evaluate the parameter recovery of the proposed estimation methodology through a simulation study and also show the potential of its use in an application to epileptic seizure data. Finally, we propose a new mixed regression model based on the Bell-Touchard distribution parameterized by the mean. Simulation studies are presented, and the methodology is applied in a neurophysiological experiment. The various studies and applications throughout the text show that the proposals yield good results and have potential use by researchers in various fields, with the codes used for parameter estimation made available.