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Computational tool to evaluate the efficency of hydrogen in internal combustion engines
(Universidade Federal de Lavras, 2025-03-20) Rincon, Alvaro Ferney Algarra; Alvarez, Carlos Eduardo Castilla; Ensinas, Adriano Viana; Rodriguez, Christian Jeremi Coronado
Behavioral studies on the efficiency of a hydrogen engine are important, as they are part of a global initiative to decarbonize the automotive sector, and this technological route for the use of hydrogen is promising within recent energy transition studies. In this sense, the exploration of new technological development routes around production, commercialization and use of hydrogen for the state of Minas Gerais and for Brazil has been proposed through various government initiatives in recent years. For this reason, this work has developed a computational tool based on a zero-dimensional mathematical model capable of predicting the efficiency of a spark ignition engine when using hydrogen as fuel. The simplicity of the model offers a quick view of the operation and thermodynamics of the engine, which reduces computational effort and produces results that represent the real behavior of hydrogen combustion. This focus helps in the study of combustion and in making decisions about the economic viability of using hydrogen in internal combustion engines. To do this, the compression, combustion and expansion processes in the Otto cycle were mathematically modeled to represent the combustion behavior of the air-hydrogen blend inside the engine cylinder, using code written in MATLAB. The mathematical model was validated with experimental data taken from the research engine bench and those reported in the literature in relation to the pressure curve for the different engines and operating conditions evaluated, and the efficiency produced by the engine under these conditions was estimated. A graphical interface was generated in AppDesigner for the computational tool, making it easier for the user to develop the behavioral and operational study of a hydrogen engine. The results obtained with the computational tool show that the estimated pressure and efficiency values are in good agreement with those found in the literature in all the cases evaluated. The maximum error when comparing the pressure curve was 1.32% for an engine with a speed of 3300 RPM. In addition, the minimum fit of the mathematical model to the experimental data was 86%, which represents a good alternative for estimating the thermal efficiency value.
O ensino de microbiologia por investigação na perspectiva CTSA: proposição de eixos temáticos sobre o papel dos microrganismos na culinária mineira para a educação básica
(Universidade Federal de Lavras, 2026-05-16) Cardoso, Poliana; Sousa, Jennifer Caroline de; Ribeiro, Alessandra de Oliveira; Lima, Lilian Patrícia; Ribeiro, Alessandra de Oliveira
This study addresses Microbiology teaching in basic education through the articulation between inquiry-based teaching and the Science, Technology, Society and Environment (STSE) approach, using Minas Gerais cuisine and the role of microorganisms in traditional foods and beverages as its contextual framework. The objective was to propose thematic axes that may support investigative pedagogical practices aimed at promoting scientific literacy and contextualizing Microbiology teaching. The research is qualitative and bibliographical in nature, grounded in theoretical references from Science Education related to inquiry-based teaching, scientific literacy, the STSE approach and food microbiology. The methodological path involved the survey and analysis of specialized literature, with the systematization of conceptual and didactic elements related to four thematic axes: artisanal Minas cheese, specialty coffee fermentation, cachaça and cocoa/chocolate fermentation. The results indicate that these themes have the potential to bring microbiological content closer to students’ sociocultural reality, fostering discussions about fermentation, food safety, artisanal production, biotechnology, cultural heritage and sustainability. In addition, the proposed approach contributes to overcoming a limited view of microorganisms as exclusively pathogenic agents, highlighting their importance in food-related, cultural, technological and environmental processes. It is concluded that the proposed thematic axes may serve as a basis for the future development of pedagogical booklets, investigative didactic sequences and other teaching strategies capable of articulating school science, regional culture and socioscientific issues in Science teaching.
Necessidades formativas de professores de língua portuguesa
(Universidade Federal de Lavras, 2026-02-27) Sales, Dayana Aparecida Lourenço Silva; Lima, Francine de Paulo Martins; Aparício, Ana Sílvia Moço; Gonçalves, Glaucia Signorelli de Queiroz
This study aims to investigate the training needs of Portuguese language teachers in a state school located in the Zona da Mata region of Minas Gerais, analyzing the challenges faced in teaching and their implications for the development of pedagogical practices. This is a qualitative, exploratory study conducted with eight teachers working in the final years of elementary school and in high school, through the application of a questionnaire and individual semi-structured interviews. The data were analyzed using Prose Analysis (André, 1983). The results reveal that initial teacher training is perceived by teachers as insufficient to address the real demands of the classroom, highlighting a persistent gap between the theoretical frameworks of the undergraduate teaching degree and the concrete demands of pedagogical practice. Regarding the demands of contemporary teaching, difficulties in incorporating active methodologies, multiliteracies, and digital technologies stand out, associated both with the absence of contextualized continuing education and the structural limitations of schools. Assessment emerges as a tense dimension, in which teachers demonstrate interest in formative practices but face institutional pressures of a bureaucratic and classificatory nature. Working conditions are a structuring factor in formative needs, with recurring reports of overload, multiple employment relationships, scarcity of time for collective planning, and feelings of professional isolation. Furthermore, reflection and research appear as latent needs, indicating the teachers' desire to recognize themselves as producers of knowledge, even though they encounter institutional obstacles to the consolidation of investigative practices in daily school life. Finally, digital literacy stands out as an emerging demand, especially in the face of the challenge of training students capable of critically dealing with the circulation of information and misinformation in digital environments. As an educational product, Teaching Cases were developed based on the participants' narratives, conceived as formative devices aimed at problematizing real dilemmas in teaching and promoting reflective and collaborative processes. It is concluded that the identified training needs are not limited to individual deficiencies, but rather reflect institutional, political, and structural constraints, reinforcing the importance of continuing education policies situated within the school context and guided by listening to teachers' experiences.
Casos de ensino: da investigação das necessidades formativas à construção colaborativa de práticas pedagógicas
(UFLA, 2026) Sales, Dayana Aparecida Lourenço Silva; Lima, Francine de Paulo Martins
Necessidades formativas de professores de língua portuguesa
(Universidade Federal de Lavras, 2026-02-27) Sales, Dayana Aparecida Lourenço Silva; Lima, Francine de Paulo Martins; Aparício, Ana Sílvia Moço; Gonçalves, Glaucia Signorelli de Queiroz
This study aims to investigate the training needs of Portuguese language teachers in a state school located in the Zona da Mata region of Minas Gerais, analyzing the challenges faced in teaching and their implications for the development of pedagogical practices. This is a qualitative, exploratory study conducted with eight teachers working in the final years of elementary school and in high school, through the application of a questionnaire and individual semi-structured interviews. The data were analyzed using Prose Analysis (André, 1983). The results reveal that initial teacher training is perceived by teachers as insufficient to address the real demands of the classroom, highlighting a persistent gap between the theoretical frameworks of the undergraduate teaching degree and the concrete demands of pedagogical practice. Regarding the demands of contemporary teaching, difficulties in incorporating active methodologies, multiliteracies, and digital technologies stand out, associated both with the absence of contextualized continuing education and the structural limitations of schools. Assessment emerges as a tense dimension, in which teachers demonstrate interest in formative practices but face institutional pressures of a bureaucratic and classificatory nature. Working conditions are a structuring factor in formative needs, with recurring reports of overload, multiple employment relationships, scarcity of time for collective planning, and feelings of professional isolation. Furthermore, reflection and research appear as latent needs, indicating the teachers' desire to recognize themselves as producers of knowledge, even though they encounter institutional obstacles to the consolidation of investigative practices in daily school life. Finally, digital literacy stands out as an emerging demand, especially in the face of the challenge of training students capable of critically dealing with the circulation of information and misinformation in digital environments. As an educational product, Teaching Cases were developed based on the participants' narratives, conceived as formative devices aimed at problematizing real dilemmas in teaching and promoting reflective and collaborative processes. It is concluded that the identified training needs are not limited to individual deficiencies, but rather reflect institutional, political, and structural constraints, reinforcing the importance of continuing education policies situated within the school context and guided by listening to teachers' experiences.