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Estudo sobre a tensão de aderência em concretos autoadensáveis com baixo consumo de cimento reforçado com fibras de aço
(Universidade Federal de São Carlos, 2023-02-17) Storch, Izabella Sant'Ana; Sartorti, Artur Lenz; https://lattes.cnpq.br/4917491051827231; Almeida Filho, Fernando Menezes de; https://lattes.cnpq.br/0447825383222965; https://orcid.org/0000-0002-6927-6377; https://lattes.cnpq.br/1751836246379877; https://orcid.org/0000-0001-9093-4832
This research studied the behavior of Self-Compacting Concrete with Low Cement Consumption (SCCLCC) with steel fibers reinforced in their properties in both states fresh and hardened, related to mechanical properties including bond strength. Variable concrets were produced, such as, reference concretes and concretes with the variation of two levels of reduction of cement consumption (12.5% and 17.5%), two levels of reinforcement with steel fiber (0.5% and 0.8%), and, finally, two diameters of steel bar for the pullout tests (10 mm and 16 mm). The results were compared with the values obtained by formulations found in the technical literature and normative codes, which underestimated the values obtained experimentally, in most cases. Equations were proposed for predicting bond strength using regression models. It has been demonstrated that it is possible to produce SCCLCC with steel fibers reinforced maintaining the properties in the fresh state (spreading test) and its mechanical performance. The equations for predicting the ultimate bonding strength (τu), τ1,0, and the bonding strength curve vs. slip (τδ) showed a high degree of accuracy with the experimental results.
Avaliação temporal da cobertura de vegetação nativa do município de Buri-SP para os anos de 2008 e 2018 e cenário futuro com as áreas de preservação permanentes restauradas
(Universidade Federal de São Carlos, 2023-02-17) Pereira, Dheosmani Sandro Marmo dos Santos; Molin, Paulo Guilherme; https://lattes.cnpq.br/1529819650942373; https://lattes.cnpq.br/8833798331340877
Agriculture and forestry are economic activities frequently found in the state of São Paulo. Consequently, there is concern about the areas occupied by these activities, since native vegetation cover areas are the most affected by conversion and consequent deforestation. Due to its location in a region with a strong agricultural and timber industry, the municipality of Buri is subject to the suppression of native vegetation, both in permitted areas and in illegal ones, such as permanent preservation areas (APPs). Multitemporal spatial analysis allows us to obtain an overview of the modifications that have occurred in recent years, identifying possible irregularities and their dimensions. This study aimed to analyze the land use transitions that occurred between 2008 and 2018 in the municipality through transition matrices, in addition to evaluation and comparison with a future scenario where all APPs are restored, considering landscape asymmetries of area analysis, nuclear area analysis, proximity index, and connectivity index, related to forest fragments of the proposed scenarios. The study was based on the use of landscape analysis tools in geographic information systems (GIS). The results showed favorable scenarios for the native vegetation cover of the municipality, with an 8.2% increase in its area in recent years, resulting from possible regeneration or reforestation projects during that period. There was also a considerable reduction in livestock areas (47.2%), but a significant increase in forestry (22.5%) and agriculture (55.5%) areas. In APPs, there was also an increase in native vegetation cover (9.3%), and a decrease in grazing (44.8%), conversions considered favorable from an environmental point of view. However, there was also an increase in forestry (47.6%) and agriculture (131.8%) uses, requiring greater attention from the public authorities and property owners to address irregularities. The future scenario obtained the best indices in all analyzed metrics, which was already expected since in such a scenario, all permanent preservation areas are restored. Comparing the 2008 and 2018 scenarios, the more recent one had an advantage in almost all aspects, favoring the maintenance of ecosystems and preservation of natural resources. However, even with such advantages, attention must be paid to the higher index of forest fragmentation found, which also demonstrates the need for an effort to achieve environmental adequacy of these properties.
Análise da teoria de Winnicott sobre o fenômeno da regressão no contexto analítico
(Universidade Federal de São Carlos, 2023-02-17) Drudi, Alec; Câmara, Leonardo Cardoso Portela; https://lattes.cnpq.br/0876503068661138
The present work aims to study the concept of regression within the theory formulated by Winnicott, following a path from the emotional development theory and the consequences of environmental failures, until reaching a relation with the phenomenon of regression, bringing practical cases from the author, in order to observe how this mechanism can arise, in different analytical contexts.
Controle H infinito não linear adaptativo baseado em processos gaussianos para quadrotor
(Universidade Federal de São Carlos, 2023-02-17) Oliveira, Guilherme Rossi de Avelar; Inoue, Roberto Santos; https://lattes.cnpq.br/6221209121565990; https://lattes.cnpq.br/8049833442437944
The use of Unmanned Aerial Vehicles (UAVs), may be subject to external disturbances, such as wind gusts, aerodynamic forces, and parametric uncertainties, depending on the location where it is to be used. Therefore, the automatic control must be robust enough to perform a pre-established task. In this work, we propose a robust control strategy based on the dynamic model to mitigate external disturbances and parametric uncertainties. The H Infinity criterion has been used for other types of robots and will be applied to quadrotor aircraft in this work. In addition to this robust character of the adopted control criterion, this work uses Gaussian processes to complement the mathematical model of the quadrotor, estimating the uncertainties not modeled by the nominal model. This combination is backed up by ensuring the stability of the resulting robust control system. An analysis of the trajectory tracking of all controllers is made, considering different levels of parametric uncertainty and external disturbances. Along with the development of the controllers, a complete study is made about the implementation of control algorithms on a real quadrotor, proposing a localization system based on the odometry of the aircraft and on a visual SLAM algorithm, using the camera present in it.
Horta agroecológica: construção do conhecimento cientifíco no espaço escolar
(Universidade Federal de São Carlos, 2023-02-17) Buzato, Gláucia Cristina Silva; Fernandes, Hylio Laganá; https://lattes.cnpq.br/1315602045624096; https://lattes.cnpq.br/6633558016675216
The present work seeks to evaluate the process of developing scientific knowledge, making its application familiar and affective through a school garden based on agroecology. This operated as a facilitating pedagogical tool for children's learning, mainly because they live in rural areas and are familiar with planting. During the research, the participants were invited to express themselves through drawings, since the imagery expression accompanies child development like a radiograph, where we can analyze how they relate to reality and cultural elements of the surroundings they live in; consequently, the drawing is the graphic “translation” of this perception. The research aimed to identify the development of scientific knowledge having as reference the reading of the drawings produced. The question that guided the research was: what are the meanings and scientific learning attributed to the growth of plants in the school garden? The participating subjects were students from a municipal school within the metropolitan region of Sorocaba-SP and enrolled in the 5th year, aged between 9 and 10 years. The methodology used was action-research and Peircean Semiotics was used as an instrument for analyzing the students' image production. The research started in May 2021, during the week of the environment and ended in December of the same year, with the end of the school year. The analyzes satisfactorily identified evidence of the development of scientific knowledge and it is possible to observe, through imagery language, a cognitive formation different from the initial one brought by the participants.
Sistema de suporte à decisão para a escolha do protocolo terapêutico para pacientes com leucemia mieloide aguda
(Universidade Federal de São Carlos, 2023-02-17) Castro, Giovanna A.; Almeida, Tiago Agostinho de; https://lattes.cnpq.br/5368680512020633; https://lattes.cnpq.br/8912074603259808
Acute Myeloid Leukemia is a chronic and disabling disease. It is heterogeneous and presents in different ways. After the diagnosis, the patient receives a risk prognosis of outcomes usually divided into three groups: favorable, intermediate, and adverse. Specialists frequently use this classification to customize therapeutic decisions. In recent decades, the standard treatment has been intensive therapy with a combination of cytarabine and anthracycline. Current risk classification is conservative and often requires specialists to resort to more information, such as the results of other exams and analyses, to select the appropriate treatment, even with little or no evidence of efficacy. This process can delay the start of treatment and worsen the patient's clinical status. In this study, we have investigated the behavior of the disease and its implications. Specifically, we carried out a systematic mapping of the literature to categorize and analyze the existing treatment guides and, mainly, to find out if any employ Machine Learning techniques. The therapeutic protocols were grouped according to the intensity of each current treatment. The disease manifests in different ways in patients; therefore, deciding on a generic therapeutic course is challenging. Thus, therapeutic strategies have become increasingly personalized and isolated for individualized clinical realities. Several variables can influence the choice of treatment guidelines, such as the patient's age, relapses, and drugs that inhibit protein actions. However, combining these and other criteria is difficult in a manual analysis, especially when genetic data are used. Therefore, it is important to resort to tools that can perform these analyzes automatically to assist specialists in choosing the best treatment protocols for their patients. In this context, this study proposes a decision support system that aims to automatically recommend sets of appropriate treatments for patients with acute myeloid leukemia by automatically predicting their mortality/survival. We used clinical and genetic data (mutation and gene expression) from two public-domain databases. The proposed system is formed by two classification committees composed of the best prediction models obtained. The results indicate that the proposed system is promising and can be used as a decision support tool for specialists, with the potential to reduce subjectivity and time in the processes of choosing treatments, resulting in more strong recommendations with fewer adverse effects, which may contribute to increasing the survival and quality of life of patients.
Development of Hematite-based photoanodes
(Universidade Federal de São Carlos, 2023-02-17) Rodrigues, Murillo Henrique de Matos; Leite, Edson Roberto; https://lattes.cnpq.br/1025598529469393; https://orcid.org/0000-0002-0513-9939; https://lattes.cnpq.br/1943658157367342; https://orcid.org/0000-0001-8445-6256
Hydrogen production via Water Splitting has been considered one of the best solutions for energy shortages and environmental pollution. The use of hematite (α-Fe2O3) as a photoanode in photoelectrochemical hydrogen production processes has been increasingly studied due to its high stability, non-toxicity, absorption in the region up to 600 nm (covering up to 40% of the solar energy spectrum), low bandgap values (between 1.9 - 2.2 eV), high accessibility and low cost, considering that iron is the fourth most abundant element in the Earth's crust. Current density studies show that hematite has a photocurrent of 12.6 mA cm-2 under solar irradiation, reaching 16% efficiency in photoelectrochemical processes in water separation. However, it has some limitations in its effectiveness due to low electronic mobility, low electrical conductivity, between 10-14 - 10-6 Ω-1cm-1, high surface state density, and slow reaction kinetics. Among the methods used for processing the hematite photoanode, we can highlight the thin films from the colloidal deposition of magnetic nanoparticles. This technique leads to the production of high-performance hematite photoanode. However, little is known about the influence of the magnetic field and heat treatment parameters on the final properties of hematite photoanodes. Thus, the first part of the work evaluated how these processing parameters in the morphology and photoelectrochemical properties of nanostructured hematite anodes. The thickness analysis demonstrated a relationship between the magnetic field and the concentration of nanoparticles used to prepare the thin films, showing that larger magnetic fields decrease the thickness. Jabs's results corroborate the existence of the influence of the magnetic field since the use of a larger magnetic field decreases the amount of deposited material, consequently decreasing the optical absorption of thin films. PEC measurements showed that at higher concentrations, using higher magnetic fields increases JPH values, and lower magnetic fields cause a decrease in JPH when using higher concentrations of nanoparticles. Even controlling the thickness and morphology of the iron oxide-based films, the pure material has a high recombination of photogenerated charge due to its low charge separation efficiency, which can generate poor electronic transport, which has hindered its commercial application. Based on the limitations of hematite, the second part of the study was to study germanium as a potentially ideal element that combines improved charge transfer efficiency and morphology control for high-performance hematite-based photoanode. Intensity-modulated photocurrent spectroscopy (IMPS) results demonstrated that the addition of Ge increased charge mobility, leading to superior charge separation efficiency compared to pure hematite photoanode. C-AFM (Conductive Atomic Force Electron Microscopy) measurements demonstrate that Ge improves electron conductivity and increases majority carrier mobility. Photoelectrochemical measurements performed at different wavelengths show that Ge interferes with the formation of small polarons, making the charges more mobile (delocalized), thus favoring the separation process of photoinduced charges. The synergistic role played by the addition of Ge resulted in a significant improvement in photoelectrochemical performance from 0.5 to 3.2 mA cm-2 at 1.23 VRHE, comparing original and Ge-hematite-based photoanodes, respectively.
Conhecimento e percepção de graduandos em enfermagem sobre precauções para prevenção de transmissão de microrganismos
(Universidade Federal de São Carlos, 2023-02-17) Silva, Darlyani Mariano da; Figueiredo, Rosely Moralez de; https://lattes.cnpq.br/2597491235073085; https://lattes.cnpq.br/0460500931218522
Health Care-Related Infections (HAIs) represent one of the major public health problems in the world, which makes it urgent to reduce their spread through adherence by health professionals to standard and specific precautionary measures. In general, the experience of the COVID-19 pandemic brought up the discussion on the transmission of microorganisms, and adherence to precautionary measures by professionals in different health care settings. In this context, questions also arise about how this topic has been addressed in nursing education, considering the relevance of this future professional in actions to prevent and control the transmission of microorganisms, whether they are related to health care or in the community. Thus, the present study aimed to identify the knowledge and perception of undergraduate nursing students about standard precautions (SP) and specific precautions (SP) to prevent the transmission of microorganisms. The realization of this project provides a standardized instrument, validated by specialists, with a CVI above 0.78 in all items. This is a specific instrument for undergraduate nursing students, consisting of three domains, namely knowledge about SP and specific precautions (SP); students' perception of their practice and characterization of teaching on the subject. The study included 582 undergraduate nursing students from all regions of Brazil, mostly women 82.6% (n=481) with a mean age of 27 years. In the PE theme, doubts were identified in the concepts of droplet precaution by 55.8% (n=325) and aerosols by 42.6% (n=248) of the participants. It was mentioned, by most of the students, 86.4% (n=503), that the emergence of COVID-19 influenced their interest in the subject of precautions and that 557 (95.70%) feel confident about how and when they should clean the hands. Regarding the approach to the PE and PP theme, 48.8% (n=284) reported being addressed in an exclusive discipline. The situational diagnosis carried out identified that the knowledge and perception of undergraduate nursing students about PP and PE measures to prevent the transmission of microorganisms are below adequate. The knowledge of undergraduate nursing students does not include the general infection prevention and control measures necessary to produce quality and safe care for patients and professionals. Thus, this study is expected to contribute to the training of future nurses by listing the essential elements to be addressed in their training.
Intervenções baseadas em mindfulness e dor relacionada ao câncer de mama: uma revisão de escopo
(Universidade Federal de São Carlos, 2023-02-17) Xavier de Souza, Daniela Maria; Demarzo, Marcelo Marcos Piva; https://lattes.cnpq.br/9242996936416312; https://orcid.org/0000-0002-7447-1839; Hortense, Priscilla; https://lattes.cnpq.br/7153278628783234; https://orcid.org/0000-0003-0554-451X; https://lattes.cnpq.br/4142936012258050; https://orcid.org/0000-0002-7136-5934
Introduction: breast cancer, as well as the consequences of its treatment, can cause symptoms such as chronic pain, which can negatively impact the lives of the affected women. The complexity of this condition requires management with a multimodal approach, considering the multiplicity of factors that can modulate the perception of pain. Objective: To map the available evidence on the use of mindfulness-based interventions for pain management in people diagnosed with breast cancer, at different stages of the disease and stages of the treatment. Methods: This is a scope review, following the guidelines of the Joanna Briggs Institute; Therefore, 3 stages of research were followed, the first of which involved the elaboration of a search strategy and its refinement, the second, the search in all databases and the third the search in the references of the publications found in the previous phase, in addition to the search in the gray literature. The eligibility criteria were developed using the PCC mnemonic (population, concept and context), including research publications carried out with women aged 18 years or above, who were diagnosed with breast cancer (population), who experienced interventions based on mindfulness directed to pain management (concept), in any clinical context (context). Publications of quantitative and qualitative studies, systematic reviews and meta-analyses, economic evidence studies, in addition to the so-called gray literature were included. No language and time limitations were placed. The databases used were PubMed, CINAHL, Web of Science, BVS, PsycInfo and Google Scholar. The protocol of this review was registered at Open Science Framework. Results: Were presented graphically and through a narrative summary, written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses - Scoping Review (PRISMA-ScR). A total of 58 publications were included for analysis, 36 of which were primary studies, 18 literature reviews and 4 clinical guidelines. There was great heterogeneity in the results of mindfulness-based interventions for pain management, whereas in some of them the effects obtained from mindfulness-based interventions for pain were not significant in terms of pain intensity, however, they presented good results on variables that may indicate that the mindfulness-based intervention enabled better management of the painful symptom and improve of the negative impact of pain on women’s lives. Pain has been evaluated, on those studies, mainly by instruments validated for this purpose. Conclusion: Mindfulness-based interventions have been used for pain management on women with breast cancer, on different stages of the disease and/or treatment, whether face-to-face, online or through apps. Several studies included in this review presented significant results for pain management in the studied population, although part of the studies did not present significant results. Some results involved the interaction of other variables with pain, such as moderators of the obtained effect or mediators.
Uma arquitetura de referência para projetar ferramentas de modernização baseadas em ADM
(Universidade Federal de São Carlos, 2023-02-17) Santos, Bruno Marinho; Camargo, Valter Vieira de; https://lattes.cnpq.br/6809743774407662; https://lattes.cnpq.br/5550740009040625
Software systems are constantly changing and this process generally makes it increasingly difficult for organizations to maintain. To help in this context, Object Management Group (OMG) proposed Architecture-Driven Modernization (ADM) that defends the realization of reengineering processes following the model-oriented architecture. One of ADM's main contributions is its sets of metamodels and its conceptual architecture. The construction of modernization tools that use the concepts of ADM have a greater chance of being interoperable. However, there are not many works in the literature that help in the construction of modernization tools based on ADM. Thus, the main objective of this Ph.D. research was to develop a Reference Architecture (RA) that supports the creation and evolution of modernization tools that are based on ADM's concepts and standards. The RA is formed by a set of diagrams representing architectural visions. For the creation of the RADM that is our Reference Architecture for ADM-based Modernization Tools, ProSA-RA was used, a process that systematizes the design, representation and evaluation of reference architectures. This Ph.D. research was evaluated through a questionnaire with ADM specialists (software developers and researchers) and software architects whose main objective was to obtain feedbacks on the acceptance of the Reference Architecture that was developed. The questionnaire that was applied brought as main results the following conclusions: (i) 100% of the participants agreed that the RA is clear and well described and (ii) 75% agreed that the RA is useful for create instances of different types of modernization tools.
Os Impactos do uso da Caderneta de Saúde da pessoa idosa e matriciamento nos indicadores de satisfação da equipe e dos idosos na Atenção Primária em Saúde
(Universidade Federal de São Carlos, 2023-02-17) Bianco, Otávio Augusto Fernandes Marques; Gramani-Say, Karina; https://lattes.cnpq.br/5096508613057074; https://lattes.cnpq.br/8696889805251278
Aging brings new demands to health systems. Therefore, it is necessary to improve the management of health resources, as well as to promote preventive and patient-centered care. One of the ways is to carry out matrix support for continuing education about health management tools and that produce indicators, such as the Health Handbook for the Elderly (CSPI). Objectives: To evaluate the impacts of using the Health Handbook for the Elderly and the presence of a matrix support carried out by an aging manager on the health management indicators of the unit and satisfaction of the team and the elderly. Methodology: This is a study experimental, longitudinal with a quantitative and qualitative approach. For this purpose, 4 USF from a municipality in Minas Gerais were selected, separating them into 2 groups, Intervention (GI) and Control (GC), followed for 6 months. In addition, 157 elderly people were selected to carry out a satisfaction assessment. Both groups received qualifications regarding the importance of the multidimensional assessment (AMD) of the elderly, the use of CSPI, monitoring of outcomes and support materials for the intervention. In the intervention group, management and follow-up of elderly cases were carried out through the CSPI, with fortnightly matrix support. The variables number of completed CSPI and satisfaction were collected from the team, and from the elderly, their satisfaction through the Short Assessment Patient Satisfaction (SAPS) instrument before and after the intervention period. Data were tabulated and analyzed using the SPSS software, adopting a significance value of 0.05. The Mann-Whitney test was used for intergroup comparison, the Wilcoxon test for intragroup comparison and the chi-square test for categorical variables. The qualitative analysis was presented by the summary of the domains raised in the professionals' responses Results: For the intergroup analysis of the team, Initially, no professional from the evaluated teams used the CSPI, after the intervention there was a difference in filling out the CSPI between GC and IG, with 75 % of GI professionals started to use the CSPI, while the CG did not use the instrument. Regarding the satisfaction of elderly patients, an initial difference was found in the domains evaluated by the SAPS in the questions satisfaction with the effect of treatment/care (SAPS 1), GC (4.57 +/- 0.69) GI (4.09 +/ - 1.1); second question related to satisfaction with the professionals' explanations (SAPS 2) GC: (4.58 +/- 0.86) IG: (4.31 +/- 0.89); satisfaction with their own choices (SAPS 4) GC: (4.57 +/- 0.94) GI (4.26 +/- 0.76); satisfaction with consultation time (SAPS 6) GC: (4.81 +/- 0.72) IG: (3.90 +/- 1.33). After the intervention, these differences remained, with the exception of SAPS 6. There was also a difference in the question satisfaction with care (SAPS 7) GC: (4.75 +/- 0.53) IG: 4.39 (+/- 0 ,75) after the intervention. In the intragroup comparison of elderly patients, there was a difference in question SAPS 6, with an increase in the score in the initial GI (3.90 +/- 1.33) in the final (4.42 +/- 1.10) and a reduction in the score in the initial CG (4.81 +/- 0.72) final (4.26 +/- 1.32). In the intragroup comparison of the teams, there was difference only in the question related to the team's knowledge about the health of the elderly, mean initial GC: (3.17 +/- 0.86) final (3.76 +/- 0.86). Regarding the qualitative analysis, there was a change in the speech pattern between the CG and GI, in which the GI began to perceive an improvement in the service and referral flow, while the CG did not have this change. Discussion: Matrix support had no impact on the satisfaction scores of either the team or the elderly, evidencing the need for a longer intervention time and the influence of multiple factors on the satisfaction of both the team and the elderly. On the other hand, matrix support increased the number of CSPI completed by the team and the perception of their use and knowledge about the health of the elderly. This shows how teams need constant support and encouragement from management and specialist professionals. Conclusion: matrix support did not impact the levels of satisfaction of the team and the elderly, but it did impact the completion of the CSPI and the feelings related to the health of the elderly, showing its importance in strengthening the use of AMD in PHC and helping the team in formulating the longitudinal care plan for the elderly.
Práticas pedagógicas nos laboratórios de educação digital: um olhar acerca do currículo de tecnologias e das aprendizagens
(Universidade Federal de São Carlos, 2023-02-17) Tadeu, Tânia; Pinheiro, Rosa Aparecida; https://lattes.cnpq.br/6292207464385037; https://lattes.cnpq.br/1485958185397856
The theme of this research refers to the technologies used in education as pedagogical tools integrated to the Curriculum of the City of São Paulo and to the principles that involve digital culture, protagonist, autonomy, inventiveness, collaboration, reflective thinking and information as a construction of knowledge. The aim of the research is to analyze, from the perceptions of the Teachers of Digital Education (POED), how the pedagogical practices take place in the Digital Education Laboratories (LED), present in all elementary schools in the city of São Paulo, through the implementation of the Technologies for Learning Curriculum (TPA), from 2017 to 2022. The theoretical foundations of the research are based on Paulo Freire, since it was during his administration as Municipal Secretary (1989 - 1991) that the Genesis Project was established, with the computer in the teaching-learning process and including the assumptions of the conceptions of programming language and research on the use of computers in pedagogical and curricular practices. Narrative interviews were used as a constituent methodological resource as an instrument of investigation, enabling dialogue with what happens with the educators who work in the digital education labs, in a qualitative approach, based on the referential provided by Jovchelovitch and Bauer (2002). The bibliographic review of the constitution of educational computing in the city of São Paulo, the systematic mapping of literature carried out in the academic databases Brazilian Digital Library of Theses and Dissertations (BDTD) and Catalogs of Theses and Dissertations, Graduate level personnel improvement coordination (CAPES),and the documents and references to existing technologies throughout the history of the municipal education system of São Paulo, were paths followed for a better understanding of the current curriculum document. The final considerations pointed out that, through the perceptions arising from the narrative interviews, the pedagogical practices developed after the implementation of the technology curriculum were re-signified by continuous training and respect for the territories in which the schools are located. Teachers emphasized the importance of partnerships among teachers and felt stronger as learning mediators. The consideration of history, identity, and previous experiences were pointed out as significant for the success of the practices carried out, even though there are still many challenges to be overcome, caused especially by the pandemic period.
Manufatura e caracterização mecânica de painéis estruturais compósitos para projetos de veículos de competição.
(Universidade Federal de São Carlos, 2023-02-17) Lopes, Gregory Aguilera; Paiva, Jane Maria Faulstich de; https://lattes.cnpq.br/7926832511513537; https://lattes.cnpq.br/3947345762108759
Due to evolution of development high performance composite, these have been increasingly used in racing car components, because the good trade-of between mass/stiffness incorporated to high levels of driver safety risk. The vehicle's chassis is an important part that can provide up to more than half of the car's total weight. The carbon fiber composite chassis, known as “monocoque”, currently has a more expensive manufacturing process than conventional ones made of stamped steel sheet metal or tubular structure, however, its mechanical properties cannot be replaced by another material keeping the same characteristic of low specific weight. At low budget teams, a feasibility study for the manufacture and maintenance of this component is necessary. The target of this project is to design the optimized sandwich panels, with the enough amount of carbon fiber fabric reinforcement, with the correct combination of the direction in the stacking of the layers, the thickness and kind of core material. The objectives involve maintaining the compromise to the combination of materials according to the minimum mechanical properties to comply with the Formula SAE 2022 rules category, associated with low specific weight and a cheaper process. The vacuum bag lamination process was used, using a glass table as a “mold” for the composite sandwich panels. The mechanical properties of the panels were characterized by 3-point bending test, perimeter shear test, Shore D hardness and the surface morphology and adhesion were analysed by Scanning Electron Microscopy (SEM). Through the results of the tests of this project, it is intended to generate a predictive model of the number of layers as a function of the weight of the fabric, and the thickness of the aramid core, with the mechanical properties necessary to dimension each part of the chassis. After the development of this project, it is intended to apply the composites developed in the manufacture of a Formula SAE monocoque chassis using the moldless method process. Highlighting the laminate with a low-density foam core, where it was possible to get mechanical properties equivalent to the structural requirements of a steel space frame chassis.