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Propriedades eletroquímicas de aços inoxidáveis 316L E 321 goivados com eletrodo de grafita e soldados por arco submerso
(Universidade Federal de São Carlos, 2022-12-20) Campesan, Gabriel Roberto; Koga, Guilherme Yuuki; https://lattes.cnpq.br/0933095081175012; https://orcid.org/0000-0003-0792-1139; Bolfarini, Claudemiro; https://lattes.cnpq.br/9231627080617037; https://orcid.org/0000-0002-3099-3694; https://lattes.cnpq.br/8152977037092071; https://orcid.org/0009-0002-6817-3242
In the maintenance and manufacturing practices of equipment in the petrochemical industry, the electric arc gouging procedure with graphite electrode is used in the preparation of carbon steel joints to be repaired or joined by the welding process. It is noted, however, that there is not much information in the literature about the magnitude of carbon contamination in stainless steels gouged with an electric arc by graphite electrode, and the consequences on the electrochemical properties. Welding standards, including N-133, Rev N from Petrobras, do not allow the use of this preparation technique for stainless steel, accepting the hypothesis that carbon contamination would be above the permissible, and it would compromise the mechanical properties and the corrosion resistance. Therefore, this project aims to evaluate the use of this process (gouging followed by welding) considering two types of austenitic stainless steels, AISI 316L and AISI 321, verifying the resulting gouging effect followed by welding on the electrochemical properties. The repaired/welded joints were studied in three different situations regarding the treatment of joint preparation after gouging, namely: i) without any type of cleaning, ii) brushing and iii) machining. Two types of joints were investigated, X and V, to simulate root pass preparation and defect repair, respectively. The degree of sensitization of the welded joint was evaluated using the double loop potentiokinetic reactivation technique (DL-EPR) according to ISO 12732 Corrosion of metals and alloys — Electrochemical potentiokinetic reactivation measurement using the double loop method (based on Cihal's method), and the susceptibility to intergranular corrosion according to ASTM A262-15 Standard Practices for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels, Practice A. The results showed that the air carbon arc gouging has no effect on the corrosion resistance of the studied alloys
Extensões do resíduo quantílico
(Universidade Federal de São Carlos, 2022-12-20) Andrade, Ana Carolina do Couto; Pereira, Gustavo Henrique de Araujo; https://lattes.cnpq.br/4536501674241631; https://lattes.cnpq.br/6232055294081210
Regression models have profound importance in analyses that aim to investigate the relationship between a dependent variable and a set of predictor variables. The diagnostic analysis is a fundamental step in validating a regression model, whose objectives are to identify possible discrepant and/or influential points and to verify possible deviations from the assumptions made for modeling. In this case, it is desirable to obtain residuals whose distribution is close to the standard Normal distribution, since their properties and behavior are known. The quantile residual is an important class of residuals with this characteristic, where its distribution is asymptotically standard Normal when the model parameters are consistently estimated. Another common problem in regression analysis is model selection, which consists in selecting the best theoretical model from a set of candidate models. The objective of this work is to develop extensions of the quantile residuals, in aspects of diagnostic analysis and model selection. To check the model fit, an asymptotically distributed standard Normal residual is introduced, which can be used for any parametric circular-linear regression model. For the detection of possible outliers, an extension is proposed on two and three-point inflated beta regression models, whose tail distribution is similar to the standard Normal distribution. Finally, three model selection criteria are introduced by testing goodness of fit using the quantile residuals in a specific context of response variable distribution selection in generalized additive models for location, scale and shape (GAMLSS).
Inclusão escolar e práticas docentes na pandemia antes e após o ensino presencial
(Universidade Federal de São Carlos, 2022-12-20) Lopes, Mariana Moraes; Mendes, Enicéia Gonçalves; https://lattes.cnpq.br/3897627554738983; https://orcid.org/0000-0003-3673-0681; https://lattes.cnpq.br/4772800166360585; https://orcid.org/0000-0002-4688-5129
The closure of schools was one of the concerns of the COVID-19 pandemic scenario. The educational inequality already present in Brazilian schools has become increasingly evident, placing teachers and families in a challenging scenario. And what happened to Special Education Target Public (PAEE) students with the interruption of face-to-face teaching? The present study aimed to describe and analyze the impacts of Remote Emergency Teaching, resulting from the closure of schools, for PAEE teachers and students. Because it is a still unknown phenomenon, an exploratory research was developed consisting of two independent studies, with specific methodological paths. Study I was developed as a quantitative and qualitative research, carried out through the online Google Forms platform, with the participation of 214 public school teachers from 111 cities, 24 states of the five Brazilian regions. Data were categorized and described in three thematic axes, namely: 1) Working conditions, guidance and support for teachers in the pandemic; two). Pedagogical practices developed by teachers with PAEE students;) From school to home reality.Study II was developed as a qualitative research, of the case study type, carried out in a College of Application of a Federal University of Brazil, through meetings carried out online, through Google Meet. It had 11 participants from three groups: a) managers of the Inclusive Education nucleus; b) Special Education teachers; c) professors of the area of knowledge. Data were categorized and described in three thematic axes, namely: Axis 1) Organization of Emergency Remote Teaching; Axis 2) Collaborative Teaching in Emergency Remote Teaching; Axis 3) Return to face-to- face teaching. The analysis of qualitative data from both studies was performed using the Atlas TI software based on Grounded Theory (GT). The results pointed to diversity in practices, working conditions and level of partnership with families in the process of schooling PAEE students. Working conditions during the pandemic directly depended on the individual condition and reality of each teacher. The educational organization in the pandemic context emotionally shook most of them, who experienced great difficulty in the process of transitioning from face-to-face to remote teaching. Teaching was organized, mostly, in an emergency remote way, even with the lack of access for many students, with positive and negative points in the schooling process of PAEE students. Although it is a diverse context, the challenges of the education of PAEE students were maintained and expanded, highlighting the whole problem of accessibility. Despite the difficulties arising from different access conditions, which accentuated educational inequalities, Study II showed that it was possible to invest in collaborative practices with technological immersion, which facilitated collaborative strategies in planning, carrying out classes and even evaluating students, from a more universalist perspective than a specialist one, designed to improve teaching for all and not just adjustments for PAEE students. However, with the return of face-to-face teaching, these practices were reduced or even discontinued, and the school was trying to organize itself to return to what it was before, with the same profile and requirements, disregarding how much society and students had advanced with pedagogical practices. collaboration and the use of technology