Navegando por Data de Publicação, começando com "2021-12-15"

Filtrar resultados por ano ou mês

Agora exibindo 1 - 10 de 10

Avaliação de riscos de segurança BGP na Internet com emulação escalável
(Universidade Federal de São Carlos, 2021-12-15) Barea, Emerson Rogério Alves; Senger, Hermes; https://lattes.cnpq.br/3691742159298316; 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.
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; Santos, Diana Gabriela Mendes dos; https://lattes.cnpq.br/9600314960182339; Orlandi, Fabiana de Souza; https://lattes.cnpq.br/7395879552721664; https://lattes.cnpq.br/6804809847103710
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.
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; Sousa, José Alexandrino de; https://lattes.cnpq.br/7737833809468759; Canto, Leonardo Bresciani; https://lattes.cnpq.br/7287108960864123; https://lattes.cnpq.br/6119680957974532; Scuracchio, Carlos Henrique; Branciforti, Marcia Cristina; Sousa, Jose Alexandrino de; https://lattes.cnpq.br/0896060959622431; https://lattes.cnpq.br/3085986187491645; https://lattes.cnpq.br/7737833809468759
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.
Organização de termos e documentos utilizando Co-clustering e agrupamento de Word Embeddings
(Universidade Federal de São Carlos, 2021-12-15) Polastri, Paulo César; Camargo, Heloisa de Arruda; https://lattes.cnpq.br/0487231065057783; https://orcid.org/0000-0002-5489-7306; https://lattes.cnpq.br/1341941141535178; https://orcid.org/0009-0000-5709-7235
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; Nakayama, Bárbara Cristina Moreira Sicardi; https://lattes.cnpq.br/9746628149674449; 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; Santos, Diana Gabriela Mendes dos; https://lattes.cnpq.br/9600314960182339; Orlandi, Fabiana de Souza; https://lattes.cnpq.br/7395879552721664; https://lattes.cnpq.br/5120041739941217
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.
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; Pessoa, Alex Sandro Gomes; https://lattes.cnpq.br/4333565964821090; 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.
Vivências como estudante de medicina da UFSCar: narrativa reflexiva
(Universidade Federal de São Carlos, 2021-12-15) Catelani, Gabriela Rios; Okido, Marcos Masaru; https://lattes.cnpq.br/5915321013293271; 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.
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; Lizarelli, Fabiane Letícia; https://lattes.cnpq.br/4525431419326559; 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.
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; Rossino, Luciana Sgarbi; https://lattes.cnpq.br/0139027055418391; 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).