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Desenvolvimento e avaliação inicial de um jogo educativo para avaliação de comportamentos pré-aritméticos
(Universidade Federal de São Carlos, 2021-12-14)
Gris, Gabriele
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Souza, Sílvia Regina de
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https://lattes.cnpq.br/8722504383832001
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Carmo, João dos Santos
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https://lattes.cnpq.br/1263046410329694
Some difficulties faced by Brazilian students in Mathematics may reflect insufficient learning from the first years of schooling. Assessment instruments developed systematically and thoroughly can contribute to the mapping of basic repertoires. This work aimed to develop an educational game to assess pre-arithmetic behavior in children at the beginning of school education. Chapter 1 aimed to identify and operationally describe the predictors and indicators of success in arithmetic through a systematic literature review. We reviewed 13 studies - 11 longitudinal and two cross-sectional - and identified 31 predictors and 15 indicators of success. We observed large conceptual and operational dispersion, and it was not possible to identify a consensus on basic skills that are important for later learning in arithmetic. After reviewing developmental studies, we conducted a systematic literature review with an emphasis on behavior-analytic production. Chapter 2 aimed to identify the main characteristics of studies in Behavior Analysis that investigate pre-arithmetic repertoires and discuss the adequacy of the concept of pre-arithmetic skills. Twenty-one studies were included for analysis, divided between studies on numerical conceptual behavior and curriculum proposals that mainly cover relations between numerals and sets. We also discuss the adequacy of the concept of pre-arithmetic skills and propose that the set of studies identified be named "pre-arithmetic behavior". After revising the first two chapters, we operationalized an educational game's tasks to evaluate pre-arithmetic behaviors and collected validity evidence based on the content of Korsan: Pre-Arithmetic (Chapter 3). After grouping and applying inclusion and exclusion criteria, 74 objective-behaviors remained that were translated into game tasks. Semantic, usability, and engagement analysis were conducted with two participants (8 and 10 years old). Content analysis was also performed after consulting three experts. Subsequently, it was evaluated the alignment between proposed in-game tasks and Base Nacional Comum Curricular based on the analysis of four experts. In the experts' evaluation, the game content is considered appropriate for evaluating pre-arithmetic repertoires. We identified the need to change the visual and wording aspects of the instructions to fit the target audience best. In study 4, we collected evidence to refine the instrument by mainly applying the game to a younger target audience. Seven children, aged between 4 and 8 years old, participated in the study. As anticipated by experts in the challenge level analysis, we identified tasks of different difficulty levels, one of the components in the alignment assessment. Adjustments are suggested so that the game works as a suitable assessment tool while also fulfilling good games' engagement and fun goals.
Produção de hidrogênio e metano a partir da co-digestão de soro de queijo e glicerol em reator anaeróbio de leito fluidizado
(Universidade Federal de São Carlos, 2021-12-14)
Almeida, Priscilla de Souza
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Silva, Edson Luiz
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https://lattes.cnpq.br/9720274214573371
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https://lattes.cnpq.br/1732909136264562
Cheese whey and glycerol are by-products of the dairy and biodiesel industry, respectively. Both by-products are highly produced and can be used in the anaerobic digestion process for energy generation due to their high organic content. The adoption of two-stage anaerobic digestion associated with the application of co-substrates brings several advantages, such as increases in COD removal and production of H2 and CH4. In this context, the objective of this research was to evaluate the co-digestion of cheese whey and glycerol in an anaerobic fluidized bed reactor (AFBR) using a two-stage process, and to verify the effect of organic loading rate (OLR) and temperature on the production of H2 and CH4. Thus, the co-digestion was performed in a thermophilic methanogenic reactor (RU-T) by increasing the OLR from 2 to 20 gCOD.L-1.d-1, with a hydraulic retention time (HRT) of 24 h. After the optimal concentration determination, the HRT was decrease from 24 to 20 and 16 h. For the two-stage process, the OLR of the acidogenic reactor (RA-T) was increased from 60 to 120 gCOD.L-1.d-1 (HRT 4 h) and of the methanogenic reactor from 2 to 20 gCOD.L-1.d-1 (HRT 24 h). Besides, the effect of temperature was investigated in the second stage using a thermophilic (RS-T) and a mesophilic (RS-M) methanogenic reactor. RU-T showed the best performance in the OLR of 10 gCOD.L-1.d-1, with methane yield (MY) of 253.0 NmL CH4.gCOD-1rem and methane production rate (MPR) of 3.2 L CH4.L-1.d-1. In the HRT evaluation, the HRT of 20 h provided the maximum MY of 292.5 NmL CH4.gCOD-1rem, while the maximum MPR was observed in the HRT of 16 h (5.1 L CH4.L-1.d-1). Acetic and propionic acid were the dominant metabolites. Regarding the two-stage process, the RA-T provided a yield of 1.7 mmol H2.gCOD-1app and hydrogen production rate of 3.9 L H2.L-1.d-1, both in the OLR of 90 gCOD.L-1.d-1, with butyric and acetic acid as main metabolites. RS-M produced the highest MY and MPR, equal to 273.2 NmL CH4.gCOD-1rem and 5.8 L CH4.L-1.d-1 in the OLR of 20 gCOD.L-1.d-1. The RS-T showed MY of 269.9 NmL CH4.gCOD-1rem in OLR 10 gCOD.L-1.d-1 and MPR of 4.4 L CH4.L-1.d-1 in 20 gCOD.L-1.d-1. Acetic and isobutyric acid were the main metabolites. Through sequencing analysis, was identified as dominant genus in RA-T Themoanaerobacterium. Archaeas of the genus Methanobacterium was the most abundant in RS-M and RU-T, while the genus Methanothermobacter was in RS-T. In general, it is verified that OLR above 10 gCOD.L-1.d-1 was harmful to RU-T and RS-T, while RS-M showed stability at 20 gCOD.L-1.d-1. The two-stage process showed better performance, however, considering the results of the HRT evaluation in the RU-T, there is the possibility of applying smaller HRT in the second stage for higher CH4 production.
Análise de recursos audiovisuais utilizados por docentes do ensino superior nas disciplinas de Libras
(Universidade Federal de São Carlos, 2021-12-14)
Fornari, Rodrigo Vecchio
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Santos, Lara Ferreira dos
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https://lattes.cnpq.br/7312070448044165
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https://lattes.cnpq.br/7411901183805783
The Brazilian Sign Language is a visual-gestural language, and its learning takes place mainly through the visual channel. Therefore, the audiovisual resources present in didactic materials for the teaching of Libras in undergraduate courses must prioritize image and content quality. A few years ago, recording, editing, and sharing a video was only possible for communication professionals or those directly linked to the audiovisual market. Today, thanks to advances in technology and the popularization of smartphones and personal computers, these tasks are performed by “ordinary people”, requiring only a little interest and curiosity to achieve these feats. However, this intuitive use of equipment and tools for video production can cause technical problems that affect the final quality of these materials. In view of this, this research aims to analyze audiovisual resources for the teaching and learning Libras as a second language (L2) for hearing students. For this purpose, it was decided to carry out a exploratory-descriptive research, with analysis of materials produced and/or used by teachers of Libras, of intermediate or advanced level, of the presential courses of licentiate and baccalaureate that aim at the formation of teachers, translators, and sign language interpreters, from Federal Educational Institutions. The professors at these institutions were contacted and, through an online form, an attempt was made to outline the profile of the participants. Interviews were carried out with some participants, aiming at a better understanding of the process of elaboration or choice of audiovisual materials. Subsequently, they were asked to send or indicate the audiovisual material used for analysis purposes. The material collected was presented in the analysis and the discussions and reflections are based on the literature in the areas of visuality and technology. As a result, this research demonstrates the need for technical support and complementary training aimed at these teachers to produce materials with audiovisual resources for their classes, resources that are extremely relevant for hearing learners. The technical analysis of the materials sent allowed the formulation of guidelines and recommendations for capturing, editing, and sharing videos to produce new, more efficient, and assertive materials for the Libras disciplines.
Evolução organizativa e alternância de poder a nível estadual no PT, PSDB e DEM entre 2010 E 2021
(Universidade Federal de São Carlos, 2021-12-14)
Thomazini, Marlon Baltieri
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Braga, Maria do Socorro Sousa
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https://lattes.cnpq.br/2311094074614215
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https://lattes.cnpq.br/6628555078488448
Este trabajo busca analizar la evolución de la estructura partidaria a nivel estatal de tres partidos políticos brasileños - Partido de los Trabajadores (PT), Partido de la Socialdemocracia Brasileña (PSDB) y Demócratas (DEM) - y su relación con la alternancia de poder de sus presidentes del estado. Para ello, se recopilaron datos empíricos de los tres partidos políticos (órganos del partido) para evaluar cómo cambió la estructura del partido estatal entre 2010 y 2021. Luego, se midió la duración del mandato de sus presidentes estatales en el mismo período. A la luz de la teoría organizativa de los partidos políticos y la literatura brasileña sobre la organización de partidos, el trabajo sostiene que los partidos descentralizados tienden a otorgar mayor autonomía a los presidentes de los estados, lo que permite que los líderes de partidos que ocupan cargos en la presidencia de los estados permanezcan en el poder por más tiempo. Esto se debe al menor uso de recursos institucionales controlados por la dirección central para inhibir los mandatos de los presidentes de estado.
Os pés da memória: uma etnografia sobre as plantas, o gado e o tempo na beira do rio São Francisco
(Universidade Federal de São Carlos, 2021-12-14)
Acypreste, Izadora Pereira
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Vander Velden, Felipe Ferreira
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https://lattes.cnpq.br/7289231173735671
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https://lattes.cnpq.br/4279348687162397
This dissertation seeks to discuss, through an approach about plants, cattle and time [tempo], how the life of riverine quilombolas is produced through continuous multispecific engagements. Residents of areas [áreas] along the São Francisco river [beira do rio], the quilombolas of Sangradouro Grande, Croatá, Gameleira and Várzea da Cruz, communities located in the municipality of Januária, North of Minas Gerais, highlight the very importance of the river in the constitution of the landscape, which is also produced by the daily conviviality [convivência] between people, plants and other living beings [viventes]. Therefore, it is through the engagements between people and these other living beings that we can understand the story [estórica] of the constitution of the landscape, which involved, and still involves, several movements, receptions [acolhidas], help [ajudas], among other reciprocal exchanges between humans and non-humans. But this landscape has been changing over time, changes that can be observed from the conviviality with the living beings of the place and against which one can also resist through alliances with each other. Since the plants are deeply intertwined with the way that riverine quilombolas understand their territories, the proposal is to describe these different connections it establishes with the lives of those who, along with them, cohabit along the riverbank. Thus, these “wonderful things” or “lovely things”, as the people on the riverbank say, serve us here not only as a starting point, but also as a common thread that connects the different discussions that make up the thesis. Through this approach, I hope to capture the most sensitive aspects of the way local residents think and relate to their plants [pés], and how, based on this relationship, they conceive and produce other aspects of their lives. In short, I aim to understand what multispecies relationships say about the way of life, the story, the territorialities, and the conviviality that generates bonds of belonging among the inhabitants of these riverine quilombola communities.
Identidades polinomiais graduadas para a álgebra das matrizes triangulares superiores sobre um corpo finito
(Universidade Federal de São Carlos, 2021-12-14)
Riva, Evandro
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Gonçalves, Dimas José
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https://lattes.cnpq.br/1668407948840456
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https://lattes.cnpq.br/4157173099755399
Let K be a field of characteristic p and let UTn = UTn(K) be the algebra of n x n upper triangular matrices over K with the usual product a . b of the elements a,b ∈ UTn. In this thesis we describe the set of all G-graded polynomial identities of UTn, where G is any group and K is any finite field. The vector space UTn with the new product [a,b] = a . b - b . a is a Lie algebra, denoted by UTn^(-). We describe the set of all G-graded polynomial identities of UT2^(-), where G is any abelian group and K is any field with characteristic p ≠ 2.
Avaliação do potencial tóxico do inseticida Clorantraniliprole e do herbicida Ametrina, isolados e em mistura, em diferentes temperaturas para uma espécie zooplanctônica
(Universidade Federal de São Carlos, 2021-12-14)
Lucca, Gisele Maria de
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Freitas, Emanuela Cristina de
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https://lattes.cnpq.br/8601993745082402
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Melão, Maria da Graça Gama
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https://lattes.cnpq.br/8342306603661310
The objective of this research was to evaluate the effects of the pesticides Chlorantraniliprole and Ametryn, isolated and mixed, on the species Ceriodaphnia silvestrii at two different temperatures and thus, carry out a preliminary risk assessment of these pesticides to Brazilian water bodies. However, comparative tests of the acute and chronic effects of isolated and mixed compounds were carried out with their standard formulation. The results demonstrated that the acute toxicity tests pointed an increase in mortality with increasing exposure time according to the selected compounds. Concerning to the chronic toxicity tests, the herbicide Ametryn significantly reduced the fertility of C. silvestrii females at concentrations from 20 μg L-1 and the insecticide Chlorantraniliprole caused hormetic effects on female fertility in the two lowest concentrations tested (0,02 and 0,04 μg L-1) and significantly reduced reproduction at the concentration of 0,14 μg L-1. In the experiments, combining the methodology of standardized tests using three temperatures (17, 23 and 30°C), the tests were carried out with the cladoceran C. silvestrii after the acclimation period. In acute toxicity tests for the insecticide Chlorantraniliprole, significant effects on the immobility of organisms were observed at low concentrations tested. In chronic tests, there was a hormesis effect at the temperature of 23°C for the concentration of 0,04 μg L-1 and significant reduction in female fertility were found for body length, number of eggs and offspring from the concentration of 0,07 μg L-1 at the three temperatures tested. For the herbicide Ametryn, the results of the acute tests showed a significant effect of temperature on the toxicity of the herbicide Ametryn, at the highest temperature tested (30°C), the average mortality occurred at lower concentrations than when compared to the mean mortality of the lower temperatures (17 and 23°C). In chronic tests, significant reductions were observed in the following parameters: body length, number of eggs and newborns, with emphasis on the temperature of 17°C, where the organisms of C. silvestrii were more sensitive than at the temperatures of 23 and 30°C. Thus, our results show that acclimation can generate significant differences in the toxicity and distribution of the sensitivity of the cladoceran C. silvestrii, indicating the need to incorporate the thermal factor in ecotoxicity tests with tropical aquatic organisms, as well as this environment variable influences biological processes of that species. In the tests with the mixture, in the acute toxicity tests of the active ingredients, the data showed dependent interaction on the dose level from the Addition of Concentration model (CA), with antagonism occurring at low doses and at high doses what was observed was synergism between its components. Chronic exposure also resulted in a dose-dependent toxicity, with antagonism occurring at low doses and synergism at high doses with a change in interaction occurring at a level equal to EC50. Given the above, it is concluded that the pesticides studied, isolated, in mixture and with acclimation at different temperatures caused toxicity in the test organism, representing potential risks to aquatic environments, suggesting more restrictive measures for the use of these compounds to ensure greater protection of freshwater bodies in tropical environments.
Circuitos curtos de comercialização de alimentos: a conquista de territórios para agroecologia no Triângulo Mineiro
(Universidade Federal de São Carlos, 2021-12-14)
Souza, Fernando Cesar de Oliveira
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Marjotta-Maistro, Marta Cristina
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https://lattes.cnpq.br/3987280258617095
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Borsatto, Ricardo Serra
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https://lattes.cnpq.br/5988987575101933
Faced with the prevailing scenario of a globalized agri-food system that operates towards the subordination of peasant agriculture, new markets are built, like the short food supply chains, as a way to reconnect food producers and consumers. This form of commercialization, as well as agroecology itself, has as a principle, antagonistic logics to those prevailing in the current food regime. In this way, peasants have sought to build by means of short food supply chains an alternative towards the achievement of greater autonomy. In view of the above, the objective of this study was to evaluate and discuss the potential of short agroecological food supply chains, as tools of peasant resistance to the corporate agri-food regime, based on a territorial approach. The methodology of the research is composed of the case study of the experience of agroecological baskets "Sowing Agroforestry", in Uberlândia/MG. Data collection instruments were: documentary analysis, participant observation and semi-structured interviews with actors related to the chain. The analysis of the results pointed to the constitution of a territory, from the social relations based on solidarity, mutual acknowledgment, transparency and learning. The chain demonstrated to be a mechanism, strategy and also product of an agroecological territoriality, ratifying the political potential of agroecology in providing counter-hegemonic paths for the constitution of more ethical, fair and sustainable agri-food systems.
Percepção dos egressos sobre a aplicação dos conhecimentos adquiridos e a relação com o desempenho no trabalho
(Universidade Federal de São Carlos, 2021-12-15)
Rodrigues, Eliane Cristine Nucci
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Lizarelli, Fabiane Letícia
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https://lattes.cnpq.br/4525431419326559
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https://lattes.cnpq.br/4222990366937103
The empirical study was carried out through a survey, using an electronic questionnaire as a data collection instrument, which obtained a sample of 49.3% of the 136 Masters graduated from the Professional Master's Program in Management of Public Organizations and Systems (PPGGOSP) from the Federal University of São Carlos (UFSCar), graduated from 2015 to 2021, addressing the use of the knowledge obtained in the Program and the relationship with their work performance. The PPGGOSP was chosen as the unit of analysis because most students are employees of public institutions, which have their own dynamics for knowledge application and dissemination. After analyzing the research results using the PLS-SEM (Partial Least Square - Structural Modeling Equation) technique, the proposed model was measured and validated, confirming the relationships between Knowledge Conversion and Organizational Learning, and between Perceived Value of Knowledge and Acquisition of Knowledge. Additionally, it was evidenced, through a multigroup analysis, that the relationships between Knowledge Conversion and Organizational Learning, and between Perceived Value of Knowledge and Knowledge Acquisition are greater for employees with less time in the institution and younger age, identifying greater knowledge application, perception of the knowledge conversion impact and organizational learning by people who have worked for less than 10 years in the same institution.
Vivências como estudante de medicina da UFSCar: narrativa reflexiva
(Universidade Federal de São Carlos, 2021-12-15)
Catelani, Gabriela Rios
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Okido, Marcos Masaru
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https://lattes.cnpq.br/5915321013293271
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https://lattes.cnpq.br/8427330561815881
As stated in the pedagogical project of the UFSCar Medicine course, the course conclusion work must be a reflective synthesis of moments during the student's graduation, contemplating teaching, assistance, extension, and research. This work is divided into topics: cycle I, cycle II, cycle III, electives, and complementary activities, which I carried out as a medical student, demonstrating my growth and professional training over the years.
Estudo Comparativo da Resistência ao Desgaste Abrasivo de Revestimentos Duros dos Tipos FeCrC, FeMn, FeTiCW e FeNbC
(Universidade Federal de São Carlos, 2021-12-15)
Teodoro, Maicon Roberto
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Rossino, Luciana Sgarbi
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https://lattes.cnpq.br/0139027055418391
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https://lattes.cnpq.br/5240597958499075
This paper evaluated the resistance to abrasive wear of four types of hard coatings applied by welding to steel used in the sugar and ethanol and mining sectors that can coat defriber hammers, sugarcane chopping knives or loader teeth, in order to increase the service life of the parts and reduce the time of maintenance stops, which optimizes the production system. The coatings evaluated were manganese austenitic (FeMn), FeCrC with high chromium content, FeTiCW containing mixed tungsten-titanium carbide and FeNbC with niobium carbide. The coatings were deposited by the electric arc welding process on a 1020 steel substrate. The characterizations of the coatings were carried out by metallography, energy dispersive spectroscopy (EDS) analysis to identify the chemical elements present in the precipitates formed and Vickers microhardness test. The coatings were submitted to two types of tests to evaluate the abrasive wear resistance of the coatings studied. The fixed ball micro-wear test was performed using 4N, 8N and 12N loads. The rubber wheel test, standardized by ASTM G65:2016, was performed with stops every 10 minutes until completing 30 minutes, and in continuous test of 30 minutes, whose wear resistance was determined volumetric loss by weighing the samples. As a result, the presence of (Fe,Cr)7C3 carbide was observed in the FeTiCW, FeCrC and FeNbC coatings. The hard ternary WTiC carbides formed in the FeTiCW coating adhered and distributed in a martensitic matrix provided the highest hardness among all the coatings studied. The microstructure of the FeNbC coating was characterized by the formation of (Fe,Cr)7C3 carbides adhered to the eutectic matrix (austenite and chromium carbides) with lower hardness than that of the FeCrC coating containing only polygonal (Fe,Cr)7C3 chromium carbides, which are smaller and homogeneously distributed in the eutectic matrix. The FeMn coating showed an austenitic matrix with micropores from the welding process with the lowest hardness among the coatings studied. The results of the fixed ball wear test demonstrated that the 8N load is more severe than the test performed with 12N loads, which due to the large contact load prevents the abrasive from being transported between the sample and the ball. In the rubber wheel wear test, it was observed that the cumulative rate of volumetric loss is maintained with increasing test time, obtaining percentage deviations below 15%. However, the allowable error calculations were below 5%, showing that both tests demonstrate repeatability and reliability above 95%, evidencing that the increase in procedure B time, which is specified in 10 minutes, is ideal, and does not require an increase in test time to evaluate the coatings. In the comparative analysis of the results obtained in the micro wear and rubber wheel test, it was observed that the FeNbC coating was more wear resistant in both tests, followed by the FeCrC coating and FeTiCW coating, with the FeMn coating being the least wear resistant. For the FeMn coating, it was observed that for the fixed ball micro-wear test, increasing the test load provided improvement in wear resistance, evidencing that the mechanical maceration mechanism increases wear resistance as the coating is subjected to the work. It was concluded that higher hardness does not always determine higher wear resistance, since the FeNbC coating with the lowest hardness (569 HV) among the carbide-forming coatings was the most wear resistant, while the FeCrC coating (630 HV) showed higher wear resistance than the FeTiCW coating that has harder WTiC carbides (669 HV), which showed the lowest resistance among the coatings due to the high hardness and brittleness of the carbides, and its wear resistance was higher only than the FeMn coating (261HV).
Desenvolvimento de um programa de intervenção com famílias que cometeram violência contra crianças e adolescentes
(Universidade Federal de São Carlos, 2021-12-15)
Guimarães, Débora Ananias
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Pessoa, Alex Sandro Gomes
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https://lattes.cnpq.br/4333565964821090
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https://lattes.cnpq.br/1639146109585581
Studies show that children and adolescents remain among the main victims of domestic violence, which represents failures in preventing and combating violence in the intrafamily context. The expectation of the international scientific community is that this worsens during and after the COVID-19 pandemic period, in view of that spaces considered protective (such as schools) were closed and victims they stay longer with their aggressors as a result of social isolation. It is therefore even more urgent to intensify efforts in the initiatives aimed at protecting these segments. Psychosocial intervention programs aimed at families can collaborate in the fight against violence against children and teenagers, as well as break with aggression and, eventually, minimize the recurrence of cases. However, programs of this nature are scarce and many of them, were not subjected to rigorous processes of scientific evaluation and validation, especially in the Brazilian reality. Based on these findings, the objective of this dissertation was to develop a psychosocial intervention program aimed at families who practiced intra-family violence against children and adolescents. Complementarily, the objective was to evaluate the content of the program, through analysis by expert judges on the subject. Based on the theoretical assumptions of the Cultural-Historical Psychology (PHC), the program took into account the reality of Brazilian families and the social and psychological demands of people assisted in the medium-complexity services of the Unified Social Assistance System. In this way, the program will train professionals (psychologists, social workers and educators) who work at SUAS to intervene with families The dissertation presents a chapter theory on the origin and perpetuation of intrafamily violence from the perspective of PHC. Next, the program is presented in its entirety, including the objectives of each session and the development of each activity. The subsequent chapter refers to the study validity of content conducted from the analysis of 3 expert judges on the subject of intrafamily violence and in psychosocial intervention programs. The evaluation encompassed dimensions about the structure of the intervention, contents, objectives, resources employees, among others. The main results of this study pointed to the need to review the proposed time for the execution of some activities, a adequacy of the language and contents addressed to the reality of the target audience, in addition to a qualification in materials and graphic resources. However, the study also revealed the quality, relevance and potential of the elaborated material, as well as its importance for the instrumentalization of professionals who work in the politics of social assistance. The entire investigative course, which culminated in the positive evaluation of the experts, motivated the continuation of the process of scientific validation of the intervention, which will be subjected to feasibility and effectiveness studies in the future. it is expected that the program developed in this dissertation can be widely disseminated in the contexto two national level and collaborate in strengthening families, so that they are minimized or broken cycles of violence that are perpetuated against children and adolescentes.
Avaliação de riscos de segurança BGP na Internet com emulação escalável
(Universidade Federal de São Carlos, 2021-12-15)
Barea, Emerson Rogério Alves
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Senger, Hermes
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https://lattes.cnpq.br/3691742159298316
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https://lattes.cnpq.br/4028338885658271
Border Gateway Protocol (BGP) is the predominant routing protocol that allows different Autonomous Systems (AS) to communicate on the Internet. Attacks on BGP typically have a significant impact as they can cause unavailability and compromise sensitive data over large geographic areas. Due to the topic’s relevance, several studies were developed that address different research areas on security in BGP. An area of study that stands out is the reproduction of testbeds for detailed protocol analysis. However, a common characteristic of validating the proposals is using a limited representation in scale and fidelity of the Internet structure. This limitation makes it impossible to have a global view of the risk associated with the attacks and identify the mitigation methods. Given this scenario, it became essential to carry out an in-depth analysis of the risks to the BGP protocol at the real and global Internet infrastructure level. This analysis demands solutions representing the real Internet topology and the accurate reproduction of the attack events on real BGP software implementations. This work presents the Minimalistic Security BGP (MiniSecBGP), an emulation-based testbed, and a methodology for risk analysis of interdomain network routing infrastructures. Our solution can use either real or synthetic data about attacks, which allows a better understanding of past attacks to “what-if” scenarios to identify more robust mitigation strategies. The validation tests demonstrated that MiniSecBGP faithfully reproduces real scenarios using topology data and attack events extracted automatically from public datasets or synthetically created by the user.
Organização de termos e documentos utilizando Co-clustering e agrupamento de Word Embeddings
(Universidade Federal de São Carlos, 2021-12-15)
Polastri, Paulo César
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Camargo, Heloisa de Arruda
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https://lattes.cnpq.br/0487231065057783
;
https://orcid.org/0000-0002-5489-7306
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https://lattes.cnpq.br/1341941141535178
There is a large amount of text documents available on the web which increases as more devices and users connect to the network. Analyzing and organizing such documents considering characteristics such as subject and keywords becomes an increasingly expensive task, but indispensable, considering tasks such as text mining and information retrieval and, therefore, ways to improve the performance of such tasks are widely investigated. Most tasks aimed at organizing documents available today, such as clustering tasks, focus on only one dimension, that is, clustering only documents considering the occurrence of terms. However, an important aspect of clustering documents is finding topics that identify groups of documents by their content. Two-dimensional clustering strategies, which simultaneously group documents and terms, can be useful in this regard. However, the representation used is, in general, in the form of matrices of high dimensionality and sparsity, which does not include any semantic information. This work presents a new approach to organize documents using co-clustering and the representation of terms in the form of embeddings. The terms of the document collection are clustered in advance, allowing for the reduction of the sparsity and dimensionality of the matrix. In addition to the new representation, the proposed strategy includes contributions to assess the outcome of co-clustering that explore the association between groups of documents and terms. In co-clustering tasks, the results showed that the representation surpasses the traditional TF-IDF representation in specific cases.
Narrativas (auto)biográficas, processos de aprendizagem da docência e desenvolvimento profissional de professores que ensinam Matemática: contribuições para o campo da educação matemática
(Universidade Federal de São Carlos, 2021-12-15)
Lagoeiro, Fabio Gomes
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Nakayama, Bárbara Cristina Moreira Sicardi
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https://lattes.cnpq.br/9746628149674449
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https://lattes.cnpq.br/5955548483302892
The (auto)biographical research in the field of Education associated with the process of teacher education and professional development have been increasingly consolidated in the scientific field. Regarding the link between Mathematics Education and (Auto)biographical Research, it is worth noting that studies guided by the (auto)biographical method have stood out on the national scene, especially in the field of research concerning the teacher who teaches Mathematics (PEM), focus of this study. In this sense, the investigation carried out, of a qualitative nature, aims to investigate aspects related to the teaching learning processes and professional development evidenced by the (auto)biographical narratives of teachers who teach Mathematics. From this objective, we sought to highlight the heuristic and formative role of (auto)biographical sources as material for the study of the trajectories of teacher education who teach Mathematics, exploring the epistemological and methodological principles of (auto)biographical narratives that enhance references and listening to oneself, the lessons learned and the implications of the training trajectories of teachers who teach Mathematics. To answer the central question – which contributions regarding the teaching learning processes and professional development of PEM emerge from (auto)biographical research for the field of Mathematics Education? – a corpus was created with scientific productions related to Mathematics Education and (Auto)biographical Research in the dialogue with the PEM, published in the Brazilian Digital Library of Theses and Dissertations (BDTD), considering the period from 1991 to 2021. In this movement, the analysis of the findings evidenced fundamental contributions of (auto)biographical research to the field of Mathematics Education, with regard to studies focused on the PEM. By highlighting trends and gaps in the production of knowledge, subsidies and paths for new studies are presented, in order to broaden perspectives and meet the demands that arise in the scientific field. It was possible to observe that the (auto)biographical approach has contributed, in the context of Mathematics Education, to the consolidation, conceptualization and characterization of the PEM as an expanding field of research.
Fragilidade social de cuidadores familiares de pessoas com deficiência física e/ou intelectual e sua relação com a depressão no contexto da pandemia da COVID-19
(Universidade Federal de São Carlos, 2021-12-15)
Silva, Cleanderson Costa da
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Santos, Diana Gabriela Mendes dos
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https://lattes.cnpq.br/9600314960182339
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Orlandi, Fabiana de Souza
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https://lattes.cnpq.br/7395879552721664
Social frailty is the decline in social relationships and social support that are directly linked to the determinants of the life course, which are age, education, income, gender, ethnicity, marital status, residential environment, lifestyle, life events and biological (GOBBENS, ASSEN, 2010). Thus, the need for care becomes a highly relevant factor to people with disabilities. On the other hand, the observed needs require caregivers, mostly informal, mainly family members. The process of caregiving can generate overload to the caregiver and also symptoms of depression. This process can be intensified due to the social changes caused by the COVID-19 pandemic. Thus, the present study aimed to evaluate the social fragility of family caregivers of people with physical and/or intellectual disabilities and its relation with depression in the context of the COVID-19 pandemic. This is a descriptive, correlational, cross-sectional research with a quantitative approach. Thirty-one individuals from a Non-Governmental Organization (NGO), located in the countryside of the State of São Paulo, participated in the research. The instruments Sociodemographic and Economic Characterization, the HALFT scale and the PHQ-2 (Patient Health Questionnaire-2) were applied; Among the results, most were male (56.70%), without a steady partner (61.30%), white (76.70%), with incomplete elementary school education (54.80), 35.5% of the participants self-assessed their health as good. Regarding frailty, 61.5% (n= 19) and 32.0% (n=10) were socially frail and pre frail, respectively. Regarding depression, 35.5% of family caregivers had probable depression. There was strong and statistically significant correlation between HALFT and PHQ-2 (r=0.604; p<0.001). It can be concluded that the level of social fragility and depression of family caregivers of people with Physical and/or Intellectual Disability was high and a strong relationship between social fragility and depression was confirmed.
Influência de compatibilização interfacial no comportamento mecânico de compósitos de polipropileno com reforço híbrido de fibras e microesferas ocas de vidro
(Universidade Federal de São Carlos, 2021-12-15)
Silva, Gabriel Matos da
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Sousa, José Alexandrino de
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https://lattes.cnpq.br/7737833809468759
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Canto, Leonardo Bresciani
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https://lattes.cnpq.br/7287108960864123
The hybridization of hollow glass microspheres with short glass fibers in polypropylene can result in low-cost, low-density polymer composites suitable for engineering. Although the addition of fillers in thermoplastic composites generally reduces mechanical strength, recent research indicates that by properly matching high and low aspect ratio fibers, it is possible to achieve desirable mechanical properties, such as stiffness, strength and toughness. In order to broaden the understanding of this mechanical reinforcement mechanism in ternary PP composites with hybrid reinforcement of FV (pretreated with aminosilane) and MEVO, this work evaluated the influence of polymer-reinforcement interfacial interactions on short-term mechanical properties. Three different interfacial compatibilization conditions were analyzed: (i) MEVO pretreated with aminosilane and PP matrix modified with addition of interfacial compatibilizer of PP functionalized with maleic anhydride (PP-g-MAH), (ii) MEVO without treatment and matrix modified with PP-g-MAH and (iii) MEVO without treatment and matrix without compatibilizer. The composites were injection molded with direct mixing of pre-extruded PP/FV and PP/MEVO binary concentrates. Tensile and flexural tests showed a slight increase in the elastic modulus of the ternary composites with higher hybrid reinforcement, regardless of the MEVO content and the interfacial adhesion of the microspheres with the PP matrix. The strength, in turn, strongly depends on the polymer-MEVO interfacial adhesion, presenting a decrease in the mechanical properties without MEVO treatment, even with the presence of the PP-g-MAH compatibilizer. With the pretreatment of MEVO with aminosilane and the use of the compatibilizer, the mechanical properties remained high, comparable to the reference binary composites PP/FV with 25% and 30% FV. The dynamic mechanical analysis (DMA) confirmed the importance of interfacial compatibilization in the mechanical behavior.
Nível de solidão e seus fatores associados em pacientes com doença renal crônica em tratamento hemodialítico
(Universidade Federal de São Carlos, 2021-12-15)
Pallone, Joice Marques
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Santos, Diana Gabriela Mendes dos
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https://lattes.cnpq.br/9600314960182339
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Orlandi, Fabiana de Souza
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https://lattes.cnpq.br/7395879552721664
Chronic Kidney Disease (CKD) is considered a worldwide public health problem and has a high morbidity and mortality rate. The disease exposes patients to a series of adjustments in their lives and their families, involving socioeconomic, physical, and psychological aspects. The absence from the school or work environment also characterizes the disease as a social problem, and in this way, social support and family functionality boost the well-being and health of patients based on the frequency or quantity of social relationships, performing important functions of an affective, educational, and socialization nature for the individual. The possible absence of this support network, along with dependence in performing activities of daily living, predisposes to possible negative outcomes, such as loneliness and depressive symptoms during the period of hemodialysis treatment. Objective: Verify the level of loneliness and its relationship with socioeconomic and health conditions, social support, family functionality and depressive symptoms in patients undergoing hemodialysis. Method: Analysis of secondary data, with a primary cross-sectional investigation, correlational with a quantitative approach, carried out in 2019, with 80 patients with CKD on hemodialysis. Applied instruments: socio-demographic, economic and health condition characterization, UCLA Loneliness Scale, Medical Outcomes Study Social Support Scale, Patient Health Questionnaire 9 and the Family APGAR. Results: Showed female prevalence (55%), white ethnicity (65%) and mean age 59,63years. In the perception of loneliness, the highest index was (55%), moderately high. Social support scored worst in the Positive Social Interaction domain, mean 74.31. In depression, showed prevalence of severe depression (28.7%). Family functioning showed good score (68.8%). There was a weak negative correlation between loneliness and all domains of Social Support, besides Family Functioning.
Lambert-F univariate distributions for asymmetrical data
(Universidade Federal de São Carlos, 2021-12-16)
Salinas, Yuri Antonio Iriarte
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Andrade Filho, Mario de Castro
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https://lattes.cnpq.br/6518161034709249
In this dissertation, we propose new univariate continuous distributions for modeling asymmetrical data. Initially, starting from a non-linear parametric transformation of an uniform random variable, we propose a new asymmetric one-parameter distribution that extends the uniform distribution, the so-called Lambert-uniform distribution. The transformation is expressed analytically in terms of the principal branch of the Lambert W function in such a way that the inverse transformation is expressed in terms of an exponential function. Consequently, the density function of the Lambert-uniform distribution has a simple closed form and exhibits increasing or decreasing monotonic behavior. Subsequently, based on the Lambert-uniform distribution, we propose a new distribution generator that allows adding one shape parameter to an arbitrary baseline distribution. The added parameter allows a variety of shapes for the density function of the resulting distribution, leading to an expansion of the skewness and kurtosis ranges of the baseline distribution. We observe that the parameter induced by the generator acts as a skewness parameter when the baseline distribution is symmetric. On the other hand, when the baseline distribution has positive support, we observe that the hazard rate function of the resulting distribution corresponds to a modification in the early times of the hazard rate function of the baseline distribution. This is exemplified through the study of four special cases obtained by considering the generalized-bimodal, slash, exponential and Rayleigh distributions as baseline distributions. We discuss the parameter estimation via the maximum likelihood method and evaluate the behavior of the estimators through simulation experiments. Finally, we consider some application examples that illustrate the usefulness of the proposed distributions in different real settings.
Planejamento de véspera da operação horária de microrredes com geração fotovoltaica distribuída integrada por inversores inteligentes via programação não linear inteira mista
(Universidade Federal de São Carlos, 2021-12-16)
Barros, João Vitor Alves de Azevedo
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Lima, Ana Paula
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https://lattes.cnpq.br/5336965542771788
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Lage, Guilherme Guimarães
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https://lattes.cnpq.br/4426242038269208
The penetration of photovoltaic distributed generation in distribution networks has become a reality; however, it still imposes challenges to be overcome, such as the operation of these networks with minimal deviations in the voltage magnitude profiles. Thus, this work proposes the daily planning of the hourly operation of microgrids in order to minimize the deviation in the voltage magnitude profiles and the minimization of active losses in the distribution through optimal tap ratio adjustments of transformers in substations, optimal adjustments of power banks remotely switched capacitors along the primary feeders and injections of active and reactive power from the photovoltaic generation distributed by smart inverters. In such a Volt/Var Optimization (OVV) problem, the discrete control variables associated with transformer taps and equivalent shunt susceptances of remotely switched capacitor banks are handled by sinusoidal penalty functions that modify the original mixed integer nonlinear programming problem into a nonlinear programming problem with only continuous decision variables. The results obtained for microgrids with 69 and 135 nodes show that the proposed OVV model and its resolution methodology are effective and efficient in reducing the deviation in voltage magnitude profiles, minimizing active losses and, at the same time, reducing of the overall reactive power demand of the distribution network.