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O ensino da função quadrática através de diferentes atividades práticas elaboradas para o ensino médio
(Universidade Federal de São Carlos, 2024-07-15)
Braçale, Vinicius Cesar
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Moura, Renato José de
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https://lattes.cnpq.br/5227908949297904
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https://lattes.cnpq.br/3470472451101524
Using practical methodologies in the classroom, this work presents a set of three activities to be applied in the classroom to assist in teaching quadratic functions in basic education. Each activity proposes to use a different methodological approach, the first being the realization of a game built in the GeoGebra software, the second a mathematical modeling on the oblique launch, and the last a practical activity proposing an investigation of the reflective property of the parabola through of constructing an experiment. The main objective of the sequence of activities presented here is to build material that can be used by mathematics teachers to teach this topic in different realities. The work presents a bibliographical research on the topic, addressing the theory necessary to understand the subject, and also describes the carrying out of qualitative research on one of its activities that was applied to a third-year high school class at a public school. In view of the analysis of the results, it can be seen that the application of the activity created a learning situation in which students were able to understand the quadratic function applied to a real situation, in the process they improved cooperation and teamwork skills, logical reasoning, in addition to recovering the concepts of the quadratic function. Thus, it was possible to understand how activities developed by active methodologies can construct different learning situations that stimulate the teaching of mathematics.
Efeitos da cloroquina sobre biomarcadores de peixe-zebra (Danio rerio)
(Universidade Federal de São Carlos, 2024-07-15)
Ferreira, Marina Tauche
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Francisco, Renata Fracácio
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https://lattes.cnpq.br/5643065656865773
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https://orcid.org/0000-0003-2257-2766
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Carvalho, Cleoni dos Santos
Chloroquine is used to treat malaria and autoimmune diseases such as lupus and rheumatoid arthritis due to its anti-inflammatory and immunomodulatory properties, but its use increased significantly during the COVID-19 pandemic due to its recommendation as a prophylactic treatment. This increase in consumption, associated with inadequate disposal, resulted in the presence of the drug in wastewater and surface waters in several countries. In this context, this study aimed to compile environmental and ecotoxicological data on Chloroquine and Hydroxychloroquine in the aquatic environment and to reproduce in the laboratory a chronic toxicity test of Chloroquine Diphosphate (CQD), lasting 21 days, in a semi-static system, using the model species zebrafish (Danio rerio), exposed to environmentally relevant concentrations detected before the pandemic (0.6 µg/L) and during the pandemic (1.8; 5.4; 16.2 and 48.6 µg/L), to evaluate the changes caused by the drug. Biomarkers were analyzed in biochemical functions, including changes in the concentration of total proteins, glucose, triglycerides and immunoglobulins (Ig); enzymatic activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and glutathione S-transferase (GST); and oxidative stress measured by protein carbonyls (PCO) and thiobarbituric acid reactive substances (TBARs). Histological analyses evaluated gill, liver and kidney changes. Data were statistically compared between the control and exposed groups, using the nonparametric Kruskal-Wallis test with Dunn's post-test, through the PAST® software. The results showed metabolic, enzymatic and histopathological disturbances in the organs from the concentrations recorded in surface waters (0.6 µg/L and 1.8 µg/L). In addition, the concentration of 1.8 µg/L was the most responsive to biomarkers of oxidative stress. In the principal component analysis (PCA), the most responsive biomarkers to DCQ exposures were AST enzyme activity, TBARs in the brain, dilation of the central venous sinus in the gills, hepatocytes with pyknotic nuclei in the liver and reduction of Bowman's space in the kidney. The innovative aspect of this research lies in the understanding of the chronic toxicity of environmental concentrations of DCQ on biomarkers of D. rerio and underscores the importance of greater awareness about the responsible use and disposal of drugs, reinforcing the need for monitoring and remediation policies to protect water resources and aquatic life.
Lógica fuzzy e o Poker : a Matemática para vencer a sorte
(Universidade Federal de São Carlos, 2024-07-15)
Branquinho, Ana Clara Boscolo
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Silveira, Graciele Paraguaia
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https://lattes.cnpq.br/6251988404047002
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https://orcid.org/0000-0002-8610-4841
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https://lattes.cnpq.br/8239279257223074
Poker is a highly popular card game worldwide, involving aspects such as strategy, technical skill, risk management, and luck, and is currently considered a mind sport. Due to the existence of monetary prizes for winners, the inherent complexities of this game are extensively studied to develop strategies aimed at improving the performance of players in high-level competitions, many of which are grounded in logic and mathematics. The objective of this dissertation was to develop a computational mathematical model based on fuzzy logic that classifies poker player profiles, specifically for the Texas Hold’em Online variant. The proposed methodology involves analyzing statistical data from players and consists of fuzzy modeling of critical variables related to the dynamics of the game. Inferences and defuzzification are performed using Mamdani and Center of Gravity methods and are computationally processed with the MATLAB fuzzy toolbox. The player data was extracted from the Poker Tracker platform, and access was facilitated through association with a professional player. Additionally, research and tests were conducted to determine standard reference values, ranges for class definitions, and validation of the results returned by the developed model. It is concluded that the model can predict actions a player might take at certain moments in the game and also their chances of success. This approach deepens the understanding of the complex
Colisões de aves em estruturas de vidro no campus de Sorocaba da Universidade Federal de São Carlos: uma ameaça que persiste
(Universidade Federal de São Carlos, 2024-07-15)
Lee, Stephanie Jin
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Piratelli, Augusto João
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https://lattes.cnpq.br/4747322084219058
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https://orcid.org/0000-0003-0268-4007
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https://lattes.cnpq.br/3581302428057569
It is estimated that collisions with glass panes cause the death of over one billion birds annually in North America alone. These collisions mainly occur because birds struggle to perceive glass as an impassable barrier due to its reflectivity and transparency, combined with various physiological, anatomical, and behavioral factors. However, studies on this issue in Brazil are still limited, which is concerning given that the country has the second-highest bird diversity in the world. This study aimed to detect evidence of bird-glass collisions on the Sorocaba campus of the Federal University of São Carlos (UFSCar) and to identify factors contributing to the frequency of these collisions. Additionally, we sought to estimate the persistence of bird carcasses in the environment and assess the negative effects of collisions on the physical condition of the birds to complement the collision data. Data on the number of collisions were collected through regular monitoring over one year. We also gathered information on building characteristics, their surroundings, and the biological traits of the species involved. To analyze whether there are differences in the number of collisions related to seasonality, building characteristics, surroundings, and species traits, we employed mixed generalized linear models (GLMMs) and univariate statistical analyses. For experimental trials, bird carcasses from collisions were placed around campus buildings and monitored to determine their average persistence in the environment and identify the species responsible for their removal. Necropsies and X-rays were conducted to identify injuries caused by these collisions. During the monitoring period, 152 pieces of collision evidence were collected; however, no significant difference was found between the number of collisions in the rainy and dry seasons. Additionally, no morphological predictor variables could explain the variability in collision numbers among species. Nonetheless, the area of transparent glass, total glass area, and black glass area in square meters were the predictor variables that best explained the number of collisions between buildings, with a positive correlation observed between these surface areas and the number of collisions. Carcasses had an average persistence of 110.69 ± 196.06 hours in the environment. Five species were identified as responsible for carcass removal: Homo sapiens sapiens, Cariama cristata, Coragyps atratus, Canis lupus familiaris, and Caracara plancus. Necropsies and X-rays revealed that the most common injuries in birds that collided with glass were fractures, cerebral hematomas, and cranial hemorrhages. This study provides evidence of bird collisions with glass structures at UFSCar Sorocaba, indicating that it is a high-risk area for such accidents. The monitoring methods used and the detrimental effects of these collisions on bird health were discussed. Urgent preventive measures are needed to mitigate this generally fatal threat.
Programação em Python no ambiente educacional: uma proposta de ensino de modelagens algébricas
(Universidade Federal de São Carlos, 2024-07-16)
Matias, Marcos José
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Silveira, Graciele Paraguaia
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https://lattes.cnpq.br/6251988404047002
;
https://orcid.org/0000-0002-8610-4841
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https://lattes.cnpq.br/5166401513381950
This study investigates how programming in Python can assist in learning algebraic modeling. The central problem addressed is the difficulty of 8th-grade students at a rural school in the interior of São Paulo in formulating algebraic models to solve everyday mathematical problems. The objectives of this work were to develop the students’ ability to recognize, generalize, and create algebraic expressions to solve problem situations. The methodology included 10 Python programming lessons with various activities designed to stimulate the development of algebraic skills. The results, obtained through process based assessments, demonstrated a significant improvement in the students’ ability to solve problems algebraically. This study contributes to highlighting the importance of computer programming in Mathematics education from the early years. Future research may further explore the impact of computer programming on Mathematics education in Basic Education.
Auto-treinamento com ruído utilizando data augmentations para tarefas de detecção de comentários ofensivos e discurso de ódio
(Universidade Federal de São Carlos, 2024-07-16)
Leite, João Augusto
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Silva, Diego Furtado
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https://lattes.cnpq.br/7662777934692986
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https://orcid.org/0000-0002-5184-9413
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https://lattes.cnpq.br/2523889749935848
Online social media is rife with offensive and hateful comments, necessitating the development of automated detection systems to manage the vast volume of posts generated every second. Creating high-quality human-labeled datasets for this task is challenging and costly, primarily because non-offensive posts significantly outnumber offensive ones. In contrast, unlabeled data is abundant, more accessible, and cheaper to obtain. This thesis explores the application of self-training methods, which leverage weakly-labeled examples to augment training datasets, in the context of offensive and hate speech detection. The core of this thesis is the paper "Noisy Self-Training with Data Augmentations for Offensive and Hate Speech Detection Tasks", which investigates the efficacy of noisy self-training approaches incorporating data augmentation techniques to enhance prediction consistency and robustness against noisy data and adversarial attacks. Experiments are conducted with both default and noisy self-training using three different textual data augmentation techniques across five distinct pre-trained BERT architectures of varying sizes. The results indicated that noisy self-training with textual data augmentations, despite its success in similar settings, decreased performance in offensive and hate speech domains compared to the default method. This finding and reveals limitations of noisy self- training methods with data augmentations for domains such as offensive speech detection, where certain specific keywords cannot be modified without introducing semantic variations.
Comportamento assintótico para equações de placa fracionárias
(Universidade Federal de São Carlos, 2024-07-16)
Picolli, Iago Aparecido da Silva
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Nascimento, Marcelo José Dias
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https://lattes.cnpq.br/7133572787875912
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https://orcid.org/0000-0003-0192-3395
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https://lattes.cnpq.br/1507534312171899
In this work, we consider two second-order fractional semilinear plate equations in time. In the first problem, we investigate an equation governed by a biharmonic operator, with clamped boundary conditions in a smooth bounded domain, modeling flight structures. In this context, we introduce a dissipative term that depends directly on the energy of the system. In the second problem, we add a memory term, resulting in a dissipative system that depends on energy and past memory. In both cases, we study local and global well-posedness and we prove the existence of a compact global attractor for the associated evolution semigroup. Additionally, we obtain the upper semicontinuity of the family of global attractors.
Chuva de sementes em remanescentes naturais, áreas de reflorestamento e agroflorestas inseridos em paisagens agrícolas: uma revisão sistemática global
(Universidade Federal de São Carlos, 2024-07-16)
Lima, Juliana Aparecida de
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Martins, Valéria Forni
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https://lattes.cnpq.br/0686674300788674
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https://lattes.cnpq.br/4618599895233798
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Agostini, Kayna
Vegetation fragments located in agricultural landscapes are important for the conservation of biodiversity and ecosystem functions. For the maintenance of such fragments, it is crucial that plant populations can regenerate naturally, especially via recently dispersed seeds (i.e. seed rain). Here we assessed the state-of-the-art knowledge on seed rain in fragments located in agricultural landscapes, focusing on the description of the seed rain, fragments, and matrixes where the fragments are immersed in. We conducted a systematic review of scientific papers published worldwide in English, Portuguese, and Spanish. We built a datasheet containing detailed information on publications, seed rain, fragments, and matrixes. Each line of the datasheet comprises information on a single fragment. We found 41 papers (161 fragments), of which 28 were conducted in Central and South America, especially in Brazil (20 papers and 78 fragments). Most fragments are composed of remaining natural vegetation (61%), show forest structure (96%), are located near other patches of natural vegetation (98%), and are immersed in pastures (50%). Only few papers informed the size of the fragments, regeneration stage of the vegetation, distance between the fragment and other patches of natural vegetation, and presence of ecological corridors. For most of the fragments, there are information on species richness (99%), diaspore abundance (98%), species composition (100%), species list (61%), and growth form of the species (39%). Only few papers reported on exotic species, dispersal syndromes, and seed size. There is floristic survey for 76% of the fragments, but the classification of species of the seed rain as autochthonous or allochthonous is reported for only 34% of the fragments with floristic survey. Our findings are a starting point for future studies aiming at biological conservation, especially by providing a detailed datasheet and identifying information still needed for a better understanding of natural regeneration via seed rain in fragments located at agricultural landscapes.
Sistemas químicos auto-organizados: morfogênese e formação de padrões
(Universidade Federal de São Carlos, 2024-07-16)
Silva-Dias, Leonardo
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López-Castillo, Alejandro
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https://lattes.cnpq.br/2599181118729458
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https://lattes.cnpq.br/2923386173329657
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https://orcid.org/0000-0003-0535-6666
Chemical systems maintained far from equilibrium, with spatially extended reaction domains, and composed of chemicals that interact non-linearly with each other, can spontaneously evolve to organized states of low entropy, known as dissipative structures. These structures are commonly observed in living organisms, and the most notable are: periodic oscillations of chemical concentration, chemical chaos, chemical waves, and stationary patterns (Turing patterns). This class of self-organized chemical systems comprises a significant number of inorganic chemical reactions with well-known mechanisms. Due to this fact, along with the dynamical similarities of these reactions to living organisms' dynamics, and the complexity of reaction mechanisms in chemical-biological processes, inorganic chemical systems are often considered in studies of dynamical phenomena in different scenarios in order to obtain results that can be extrapolated to understanding similar phenomena in living systems. From this perspective, this thesis presents an investigation of morphogenesis and spatio-temporal pattern formation in conditions that are either relevant or motivated by biology. This is accomplished through four main works. In the first, we investigated the emergence of Turing patterns in the chlorine dioxide–iodine–malonic acid (CDIMA) reaction in a domain that continuously grows as a rotating spiral. From this study, we observed the formation of a new class of stationary spiral patterns with different multiplicities. In the second, we evaluated the effects of Faraday waves on the formation of chemical waves in the Belousov-Zhabotinsky reaction, aiming to discriminate acoustic frequencies through the spatio-temporal dynamics of the reaction. We noted that Faraday waves interfere with the local process of mixing, altering the speed and morphology of the chemical waves. However, this system was ineffective in discriminating the applied acoustic frequencies. In the third work, we developed a simple and practical procedure to obtain transient Turing patterns in a batch system from the CDIMA reaction. From such an experimental procedure, we obtained patterns with good resolution and stability. Finally, in the fourth one, we proposed a model based on the classical theory of phase separation and reaction-diffusion systems to describe morphogenesis in a system of synthetic chemical cells. Through numerical simulations, we were able to elucidate the physical-chemical mechanism of this process and to identify that the difference in osmotic pressure between two cells in different chemical states, due to the break of spatial symmetry caused by the emergence of a Turing state, triggers the physical morphogenesis.
O papel da informação na política pública de assistência à saúde suplementar de servidores da UFSCar
(Universidade Federal de São Carlos, 2024-07-17)
Moraes, Tainara Gabriele de
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Justo, Carolina Raquel Duarte de Mello
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https://lattes.cnpq.br/9209489935777843
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https://lattes.cnpq.br/2415431250469293
The execution of administrative procedures structures the implementation of public policies, and the recognition of the norms and rules that regulate them is fundamental for their correct execution. The reimbursement of supplementary health expenses for civil servants of the Union, autarchies, and federal public foundations constitutes a health assistance benefit. To access this benefit, it is necessary to prove the contracting of a health care plan, along with the accountability and verification of expenses with the contracted plan as a means of controlling this policy. This investigation identifies knowledge gaps among UFSCar beneficiary employees that may result in undue payments or the non-granting of the due benefit. Therefore, beneficiaries need to know their rights and duties related to this public policy through clear access to the information and specifications that regulate the benefit. The objective of this work is to analyze the implementation of supplementary health assistance for employees and to develop proposals for actions to improve the dissemination of information in the stages of the process flow. The research adopts a qualitative, descriptive, and exploratory approach. To this end, a questionnaire is applied to UFSCar beneficiary employees and an interview is conducted with a public employee from the human resources department of another federal higher education institution.
O uso de gamificação no ensino da ferramenta de Linha de Balanço
(Universidade Federal de São Carlos, 2024-07-17)
Correa, Cecília Carniello
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Serra, Sheyla Mara Baptista
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https://lattes.cnpq.br/8528385567782505
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https://orcid.org/0000-0002-9508-976X
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https://lattes.cnpq.br/6532925191722912
The low level of knowledge of lean principles and tools by professionals in the construction industry may be attributed to the absence of a specific content approach during their training process. Therefore, the adoption of gamification as a teaching strategy could help enhance training effectiveness, increase interest, and improve retention of learning among participants. Supporting this perspective, this dissertation conducts an experiment with undergraduate students in Civil Engineering at the Federal University of São Carlos, combining gamification with traditional lectures. This study aims to assess the impact of gamification on the teaching of the Line of Balance (LOB) tool, which was adopted by the lean philosophy. To achieve this goal, a pilot experiment was conducted to validate data collection instruments and the game application method. Following the analysis and necessary corrections, a second application was conducted. Data for the research was gathered through two knowledge tests (quantitative analysis) and three qualitative questionnaires. Participants were divided into a control and intervention group to compare the traditional teaching method (control) and this method combined with gamification (intervention). Statistical analysis of the collected data revealed that students in the intervention group achieved better results in the tests. It was also noted that students participated much more actively and showed significantly higher engagement in the gamified class compared to the traditional lecture. The results indicate the positive influence of the use of gamified approaches in teaching LOB. The experiment demonstrated the feasibility of integrating gamification into the classroom, offering potential benefits to the construction industry at large.
Avaliação de pastas e argamassas geopoliméricas porosas obtidas a partir da incorporação de espuma pré-formada
(Universidade Federal de São Carlos, 2024-07-17)
Soares, Gustavo de Albuquerque
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Luz, Ana Paula da
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https://lattes.cnpq.br/3470395641242374
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https://lattes.cnpq.br/1748736510715140
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https://orcid.org/0000-0002-9702-9488
The development of sustainable materials has been the subject of various studies in a broad technological context. In this regard, geopolymers are identified as potential binders for various applications, including acting as an alternative to Portland cement. This study investigated the production and properties of porous geopolymeric pastes and mortars, prepared from a mixture of metakaolin with an alkaline solution containing nano-silica and NaOH. Approximately 0.45 wt.% of xanthan gum was added to the water and foaming agent solution during foam preparation to enable the formation of stable and small bubbles, which are fundamental for the preparation of homogeneous porous geopolymers with uniform pores. The incorporation of 5 wt.% to 10 wt.% of pre-formed foam into the produced pastes resulted in the creation of specimens with low density, high porosity, low modulus of elasticity and reduced mechanical strength. In general, the pastes exhibited average pore diameters between 99 and 137 µm and high air permeability due to the interconnectivity of the present pores. For the porous mortars, compositions containing geopolymer or Portland cement as binders and different foam contents were evaluated. Samples with low density (1.18 to 2.11 g/cm³) and high porosity were obtained. Those containing geopolymer showed higher total porosity compared to cementitious ones. This characteristic resulted in compositions with low stiffness and mechanical resistance, as well as low thermal conductivity (0.29-0.34 W/m.K). The results confirmed the feasibility of producing porous and homogeneous microstructures, highlighting the great potential of geopolymers to act as substitutes for Portland cement in lightweight mortar compositions.
O autismo e as práticas de cuidado na atenção básica à saúde: a perspectiva de profissionais
(Universidade Federal de São Carlos, 2024-07-17)
Polli, Letícia Migliatti
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Fernandes, Amanda Dourado Souza Akahosi
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https://lattes.cnpq.br/7901666626822625
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https://orcid.org/0000-0001-8006-8117
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https://lattes.cnpq.br/8666446013166153
Autism, as a nosological classification, has changed over the decades since the studies of Kanner and Asperger in the 40s. The prevalence has risen significantly every year, raising important debates about care, as well as the pathologization and medicalization of childhood. The history of care for autistic children and adolescents in Brazil was marked by a late start and by disputes between different camps. Even though there are differences of opinion, public policies indicate that Primary Health Care (PHC) is fundamental to the care network. This emphasizes the importance of PHC both for monitoring this population and articulating the intersectoral network, even though the literature points to numerous challenges ranging from a lack of professional training to political direction. That said, it is essential to carry out studies that address the reality of autistic children in the area, from the PHC perspective, with a view to developing effective care strategies to meet their health needs. The general objective of this study was to identify and understand how care practices for autistic children and their families have been operationalized in PHC. The specific objectives were to understand how the team identifies autistic children in the territory and what procedures/strategies are adopted when autism is suspected; to understand what the main challenges and possibilities are in relation to care practices for autistic children and their families in PHC. As for the methodology adopted, this is an exploratory, descriptive study with a qualitative approach. There were 19 participants, including managers and professionals from six teams in the Family Health Units (USF) of a medium-sized municipality in the interior of the state of São Paulo. The instruments used for data collection were two forms - one to identify and characterize the participants and the other to characterize the USF - and a semi-structured interview. Data was collected in person. The data was analyzed using Bardin's categorical analysis. As a result, in relation to the USFs, it was found that all the units had a minimum team of professionals, only half offered activities aimed at children and young people, but which included autism, almost none were mentioned. The majority of the participants are women, from a variety of professional backgrounds. Their activities ranged from general clinical care to preceptorship and management of the Unit. Few reported having previous experience with autism. It was possible to understand that autism is hardly recognized by PHC professionals, with community agents being mentioned as important players in identifying children with suspected autism in the territory. In addition, there is a logic of care centered on referral to specialists, often justified by a lack of professional training. Participants also highlighted the importance of childcare and territorial care for this population and the many challenges to operationalizing care at this level of health care, such as lack of knowledge of existing services and flows, lack of resources and difficulties in articulating the network. This study contributed important elements for the planning and implementation of care strategies for autistic children within the scope of PHC, from the perspective of psychosocial care. In this sense, it is emphasized that the challenges for the operationalization of care remain, as already evidenced in previous studies, and it is necessary to advance so that it is possible to actually guarantee the rights of this population, such as expanded and comprehensive care, school inclusion, based on territorial care practices, access and articulation of the intra and intersectoral network.
Redes neurais em grafos para aprendizado positivo: uma abordagem utilizando reescrita
(Universidade Federal de São Carlos, 2024-07-17)
Messias, Guilherme Henrique
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Iasulaitis, Sylvia
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https://lattes.cnpq.br/4226275371443693
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https://orcid.org/0000-0002-3526-1003
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Valejo, Alan Demétrius Baria
Given the increasing volume of data generated by society, the task of classification has become even more complex, as some supervised classification algorithms require a substantial amount of labeled data to achieve good performance. On the other hand, even with the use of a few labeled examples from the positive class, relevant results can be obtained by semi-supervised learning algorithms based on Positive and Unlabeled Learning (PUL). These algorithms can be applied to a variety of data types, including relational data, which can be represented by graphs. In this context, machine learning algorithms based on neural networks show relevant results, particularly Graph Neural Networks (GNNs). Additionally, the recent research area of graph rewiring has shown a performance gain in GNNs. This work aims to explore the use of graph rewiring and graph neural networks to address PUL problems, under the hypothesis that these approaches are capable of learning a latent representation space biased by the positive data. The results of experiments conducted on a range of datasets show that the proposed approach is superior to classical and current algorithms in the literature, both in negative data extraction and in the PUL task.
O realismo especular: a perspectiva de Piero della Francesca na construção do olhar fotográfico moderno
(Universidade Federal de São Carlos, 2024-07-17)
Fortunato, Ana Cláudia Maurino
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Costa, Alan Victor Pimenta de Almeida Pales
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https://lattes.cnpq.br/5414466437997230
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https://orcid.org/0000-0001-8715-4229
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https://lattes.cnpq.br/4568424670948962
Esta investigación tiene como objetivo explorar las formas en que los procesos de educación visual organizados por la técnica de la perspectiva en la obra de Piero della Francesca (1415 – 1492), contribuyeron a consolidar la noción de realismo fotográfico. Analizaremos las conexiones entre las pinturas de Piero della Francesca y la fotografía moderna, buscando comprender cómo los conceptos matemáticos, tales como la razón, la proporcionalidad, la tridimensionalidad y la perspectiva, fueron parte de esta construcción visual que nos orienta en nuestra forma de ver y observar. Más allá de eso, también nos guía incluso en nuestra manera de tomar imágenes y realizar registros. Esta construcción, que involucra el realismo fotográfico, conlleva contradicciones que lo denuncian, mostrando que una fotografía difiere de lo real por varios factores y que nunca será igual a lo real, representando así el realismo pero no la realidad.
Kapü kameakuē: o que colhi com Inute Tuta e os Kwazá-Aikanã
(Universidade Federal de São Carlos, 2024-07-17)
Sucupira, Gicele
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Vander Velden, Felipe Ferreira
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https://lattes.cnpq.br/7289231173735671
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https://orcid.org/0000-0002-5684-1250
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https://lattes.cnpq.br/0273614920990040
This thesis is an anthropological exercise based on my learning from the indigenous sage Inute Tuta and the Kwazá-Aikanã people from the Dois Irmãos village in the Kwazá’s Rio São Pedro Indigenous Land, located in the southern part of the state of Rondônia. With Inute Tuta, I sought to 'gather' what the Kwazá-Aikanã wish to record for non-indigenous people and for future generations. The mukudu (body ornaments), indigenous names, photographs, soccer, and açaí are important means of relating to others and showcasing who the Kwazá-Aikanã are. From the mukudu, central theme of Inute Tuta's work, I learned about 'utilization,' a Kwazá-Aikanã way of living that expresses itself in an ethics of life, with rules and guidelines for relationships with others, in which one cares for, values, respects, and uses only what is necessary of what is available. This way of living is essential for survival in a world where the assaré (non-Indians) are the majority and scarcity is increasingly present.This is the first ethnography about the Kwazá-Aikanã following the guidance of the people themselves, particularly that of Inute Tuta.
Análise de meios filtrantes em filtros de mangas do processo de dessulfuração da siderurgia
(Universidade Federal de São Carlos, 2024-07-18)
Vieira, Ana Cristina Coelho
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Sartim, Rafael
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https://lattes.cnpq.br/0380809249444032
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Aguiar, Mônica Lopes
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https://lattes.cnpq.br/0431688649128529
The emissions of ultrafine particles in the air are considered a global problem. The increase is linked to economic development and extensive urban expansion. These particles are inhalable, and exposure to them can cause various diseases or even lead to death. As a result, there has been a need to develop and optimize methods and equipment to control their emissions. In this context, bag filters stand out as one of the most commonly used filters due to their high filtration efficiency and stability. However, the filter medium used directly affects filtration efficiency, and how the filter medium is manufactured—such as needle felt and hydroentangled felt—also impacts efficiency and lifespan. Given the existing gap in the literature regarding the influence of filter medium manufacturing techniques on filtration efficiency and their impact in industrial settings, the objective of this research is to analyze and compare the filtration performance of filter media manufactured using needle felt and hydroentangled felt techniques, both virgin and with 3- and 4-year usage, in the bag filter system of the desulfurization process in the steel industry. The particulate material and filter media used were characterized to understand their behavior during filtration tests. Filtration tests were conducted using a test filter based on the VDI 3926 standard, with pulse-jet cleaning, evaluating collection efficiency and pressure drop evolution over 30 filtration cycles. The results of particulate material characterization showed that it is predominantly composed of calcium and iron, with a median aerodynamic diameter of 2.64 µm. The hydroentangled filter medium, along with a larger fiber diameter, exhibited lower thickness and permeability compared to the needle felt. Consequently, the penetration of particulate material into the hydroentangled medium was lower, facilitating the cleaning process of the filter bags and increasing filtration efficiency. After 30 filtration cycles, the used hydroentangled filter medium achieved an efficiency of approximately 99.9%, while the needle-felt filter medium reached approximately 99.7%. Regarding lifespan over the years, the 4-year-old filter bags showed greater residual pressure drop than the 3-year-old bags, as expected due to particle accumulation in the filter medium over time. However, the increase in residual pressure drop was smaller for the hydroentangled bags than for the needle-felt bags, resulting in a longer lifespan. Therefore, under the analyzed conditions, the hydroentangled filter medium demonstrated greater effectiveness, with a longer lifespan and lower residual pressure drop during filtration.
Bounds on the critical parameter for the frog model on trees
(Universidade Federal de São Carlos, 2024-07-18)
Pena, Caio Augusto de Carvalho
;
Gallo, Alexsandro Giacomo Grimbert
;
https://lattes.cnpq.br/4037274656833325
;
https://lattes.cnpq.br/8701983533033982
We consider the frog model with a lifetime on infinite trees. In this model, frogs (particles), when awake, perform a symmetric random walk on the tree, waking up all dormant frogs at the sites visited until they die. We consider variations of the model by changing the structure of the tree (oriented or not, random or not) and the survival distribution. In these models, the survival probability of a frog is controlled by a parameter \( p \in [0,1] \), and there is a critical value \( p_c \) such that if \( p < p_c \), then only finitely many frogs are awakened with probability 1, while if \( p > p_c \), infinitely many frogs are awakened with positive probability. The thesis is dedicated to obtaining lower and/or upper bounds for this critical parameter as a function of structural constants of the considered models.
Soldagem de tubos centrifugados brutos de fundição e carburizados da liga 35Cr45NiNb: microestrutura e propriedades mecânica em tração e fluência
(Universidade Federal de São Carlos, 2024-07-18)
Corsi, Waleska Laisa
;
Zepon, Guilherme
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https://lattes.cnpq.br/7924187202036614
;
Koga, Guilherme Yuuki
;
https://lattes.cnpq.br/0933095081175012
The 35Cr45NiNb alloy is widely used in hydrocarbon cracking furnaces due to its excellent resistance to oxidation and creep. However, this material is susceptible to carburization, which causes deterioration of mechanical properties and makes it necessary to replace the carburized sections. The remaining tubes in the equipment are eventually in an aged and/or carburized condition, therefore, they have low weldability, making it difficult to join new tubes, and compromising the mechanical performance of the weld. The objective of this work was to evaluate the effects of the welding process on the mechanical properties in tensile and creep of as cast and carburized 35Cr45NiNb tubes. The joining of the as cast segments (B) and tubes with approximately six years of use (C) was carried out using the Gas Tungsten Arc Welding (GTAW) technique, resulting in the joints B-B, B-C and C-C. The micrographs of the weld joint obtained by scanning electron microscopy (SEM) showed the growth of precipitates in the heat affected zones (HAZs), mainly in those located between segments C and the weld metal (WM), which acquired sizes relatively larger than those of the base metal (BM). These microstructural heterogeneities, combined with those pre-existing in the BM due to aging and carburization, caused a gradual reduction in the tensile strength and elongation at room temperature, as well as a decrease in the creep failure time (CFT) at 1100 ºC and 16 MPa.
Redução de CO2 a partir de reações de catálise homogênea com complexos bimetálicos de cobalto
(Universidade Federal de São Carlos, 2024-07-18)
Santos, Mayara Fontanelli dos
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Marques Netto, Caterina Gruenwaldt Cunha
;
https://lattes.cnpq.br/8042236152815373
;
https://orcid.org/0000-0002-3285-4129
;
https://lattes.cnpq.br/9422151542979888
This work addresses a topic of significant contemporary relevance: the growing concern about pollution caused by greenhouse gases, which exacerbate global warming and consequently result in extreme weather events in various regions worldwide. This study presents important data on homogeneous catalysis reactions and CO2 electroreduction, aiming to produce formaldehyde and methanol—compounds that are highly useful in the industry—using a bimetallic cobalt (II) complex as a catalyst. The research delves into the analysis of metallic complexes, providing detailed information on the coordination between the metal and the ligands, and justifying the choice of cobalt as the catalytic metal. In the context of CO2 reduction, different types of catalysis are explored, including photocatalysis and electrocatalysis, as well as the three main forms of CO2 capture: pre-combustion, post combustion, and direct air capture. By comparing with complexes reported in the literature, it is concluded that the CO2 reduction process using a bimetallic cobalt (II) complex is feasible. The presence of two metals in the complex offers significant advantages, enhancing the selectivity and efficiency of the catalytic process and the presence of the ligand can affect the stability.