66 results on '"Francisco Evangelista"'
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2. Narrativas da formação continuada: experiências de reconhecimento e valorização dos saberes profissionais
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Adriana Aparecida Dias and Francisco Evangelista
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- 2022
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3. Reliability and uncertainty quantification of the net section tension capacity of cold-formed steel angles with bolted connections considering shear lag
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Luciano M. Bezerra, Valdeir Francisco de Paula, Jéssica Ferreira Borges, and Francisco Evangelista
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business.industry ,Tension (physics) ,Lag ,Building and Construction ,Structural engineering ,Cold-formed steel ,law.invention ,Shear (sheet metal) ,Section (archaeology) ,law ,Uncertainty quantification ,business ,Reliability (statistics) ,Geology ,Civil and Structural Engineering - Abstract
In cold-formed steel members under tension and connected with bolts, the resistance capacity of the net section should be calculated, taking into account the shear lag phenomenon. This is done through the net section reduction coefficient, Ct. Different Standards show different equations for Ct. In this work, experimental laboratory data of cold-formed steel angles from the authors are used for the evaluation of the accuracy of the predictions of the net section capacity of members under tension. Such predictions are given by the equations of AISI, Eurocode-3, Brazilian standard NBR 14762, and also by a predictive equation previously proposed by the authors. The paper shows how each equation predicts the tension member resistance capacity in front of the experimental data. Most of the equations in the design standards have good predictions when more sections of the steel angles are connected. The results show that the AISI standard presented the best resistance capacity prediction and lower standard deviations of the output response upon uncertainty.
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- 2020
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4. Contamination of Soil, Water, Fresh Produce, and Bivalve Mollusks with
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Nadia María, López Ureña, Umer, Chaudhry, Rafael, Calero Bernal, Santiago, Cano Alsua, Davide, Messina, Francisco, Evangelista, Martha, Betson, Marco, Lalle, Pikka, Jokelainen, Luis Miguel, Ortega Mora, and Gema, Álvarez García
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- 2022
5. A generalized finite element interface method for mesh reduction of composite materials simulations
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Francisco Evangelista Jr, GUILHERME OLIVEIRA FERRAZ DE PAIVA, and Gelson Alves
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Mechanics of Materials ,Mechanical Engineering ,Automotive Engineering ,Aerospace Engineering ,Ocean Engineering ,General Materials Science ,Civil and Structural Engineering - Published
- 2022
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6. O direito de narrar na obra freireana
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Adriana Alves Fernandes Costa, Guilherme Do Val Toledo Prado, and Francisco Evangelista
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General Medicine - Abstract
O trabalho procura compreender a presença da narrativa, em parte da obra freireana, como base constitutiva do pensamento de Freire. A partir dos escritos escolhidos pelos autores, criteriosamente, o procedimento de investigação se fez atento à leitura cuidadosa e rigorosa com vistas à busca de elementos que constituem o ato de narrar do autor. No decorrer dos discursos existentes, foi possível entender que o revisitar memórias e a evidente posição do narrador não unicamente em/como eventos isolados, mas enquanto prevalecentes componentes que deflagraram o ser e estar de homem-educador-ser humano, em distintos espaçostempos. Este movimento circunstanciado de pesquisa permitiu compreender que a narrativa é exercida de modo constante nas obras analisadas, sabidamente como elemento que produz conhecimento de si e de um coletivo, um exercício do direito de contar que se efetua como práxis constitutiva e transformadora do mundo e dos seres humanos.
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- 2021
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7. UNCERTAINTY QUANTIFICATION OF FRACTURE POTENTIAL AT CONCRETE-ROCK INTERFACE
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Mariana de Alvarenga Silva and Francisco Evangelista Junior
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Interface (Java) ,Fracture (geology) ,Geotechnical engineering ,Uncertainty quantification ,Geology - Published
- 2021
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8. INFLUÊNCIA DO NÚMERO DE SEÇÕES DE CONECTORES NA EFICIÊNCIA DA RUPTURA POR SEÇÃO LÍQUIDA EM CANTONEIRA DE CHAPA DOBRADA
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Valdeir Francisco de Paula, Francisco Evangelista, Luciano M. Bezerra, and Jéssica Ferreira Borges
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- 2021
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9. O processo de transformação fisico-ambiental da bacia do Ribeirão Vidoca relacionado com os aspectos de urbanização
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Souza, Antonio Francisco Evangelista de, Pereira, Sueli Yoshinaga, 1961, Perez Filho, Archimedes, Zakia, Maria Jose Brito, Universidade Estadual de Campinas. Instituto de Geociências, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Planejamento urbano ,Bacias hidrográficas ,Meio ambiente ,Sistemas de informação geográfica - Abstract
Orientador : Sueli Yoshinaga Pereira Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias Resumo: O objeto de estudo é a Bacia do Ribeirão Vidoca e seus processos de urbanização e transformação. Foram avaliadas as transformações fisico-ambientais da área da bacia, que impedem a renovação dos recursos hídricos e comprometem a qualidade da água. As principais transformações analisadas foram: Retificação do curso da Bacia do Ribeirão Vidoca e seus afluentes, Assoreamento, Canalização, Aterramento de áreas de Várzea, desmatamento de Matas CHiares e das Nascentes, impermeabilização na área da bacia e lançamento de efluentes domésticos e industriais. Determinou-se como agente de transformação o processo de Urbanização, enfocando-se os aspectos de infra-estrutura urbana. Selecionou-se a Bacia do Ribeirão Vidoca, por estar densamente urbanizada, sofrer uma forte transformação e, conforme a proposta da nova Lei de Zoneamento Urbano de São José dos Campos, localizar-se em zona de expansão urbana. A análise das relações entre Urbanização e as transformações ocorridas na Bacia do Ribeirão Vidoca é fundamental para ações de Planejamento Urbano e Regional, assim como para a conservação dos Recursos Hídricos Abstract: The study object is the Basin ofthe Vidoca Brook and its processes ofurbanization and transformation. The physical-environmental transformations of the basin area had been evaluated, that hinder the refteshing of hydrics resources and compromise the quality of the water. The main analyzed transformations had been: Rectification ofthe course ofthe Basin of the Vidoca Brook and its affluents, Silting Up, Canalization, Landfilling ofFertile valley areas, deforestation of CHiares Bushes and the Springs, waterproofing in the area of the basin and launching of domestic and industrial effiuents. The process of Urbanization was determined as transformation agent, focusing itself the urban inftastructure aspects. It was selected the Basin of the Vidoca Brook, for being densely urbanized, suffering one strong transformation and, as the proposal of the new Law of Urban Zoning of São José dos Campos, to be situated in zone of urban expansion. The occured analysis of the relations between Urbanization and Transformations in the Basin of the Vidoca Brook are basic for actions of Urban and Regional Planning, as well as for the conservation ofthe Hydrics Resources Mestrado Administração e Politica de Recursos Minerais Mestre em Geociências
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- 2021
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10. RELAÇÕES ÉTNICO-RACIAIS NO BRASIL
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Anderson Rogério Junque and Francisco Evangelista
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Black culture ,Cultural identity ,Perspective (graphical) ,Ethnology ,Sociology ,Social subject ,Location ,Being in the world - Abstract
Resumo: O presente texto procura discutir as relações étnico-raciais pautadas no reconhecimento do outro e também de si mesmo, no sentido de olhar à própria origem e orgulhar-se dela, independentemente da localização geográfica ou da origem cultural. Reflete sobre a importância da identidade cultural e sua importância na construção histórica da cultura brasileira, onde o processo de partilha dos elementos culturais diversos e diferentes entre si, deu origem à um sujeito social diferente ao modo vivido pela visão eurocêntrica. Apresenta a pluralidade existente nos diferentes modos de ser e de estar no mundo como riqueza que precisa ser compartilhada e respeitada na realidade histórica atual no Brasil. O texto defende que a diferença cultural deve ser encarada como possibilidade de ver o mundo de outra maneira, com os olhos de outros, com outra visão da realidade, e não como movimento que separa aquilo que é diferente. Palavras Chaves: Relações Étnicos-Raciais; Identidade Cultural; Cultura Negra.
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- 2020
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11. A methodology to assess the evolution of viscoelastic properties of hardened cement pastes through dynamic mechanical analysis
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Fabiano Campos Macedo, Francisco Evangelista Junior, and Márcio Muniz Farias
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Cement ,Materials science ,Phase angle ,0211 other engineering and technologies ,020101 civil engineering ,Young's modulus ,02 engineering and technology ,Building and Construction ,Dynamic mechanical analysis ,Viscoelasticity ,Sweep frequency response analysis ,0201 civil engineering ,symbols.namesake ,Creep ,Frequency domain ,021105 building & construction ,symbols ,General Materials Science ,Composite material ,Civil and Structural Engineering - Abstract
This paper presents a new methodology to determine dynamic mechanical characterization of cements pastes in the frequency domain, and also non-aging time dependent creep compliances from interconversion of short duration torsional frequency sweep tests on hardened cement pastes. The experimental results show the behavior of the phase angle, storage and loss moduli in frequency domain at three loading ages for two pastes with different water cement ratios. Validation is performed through comparison between creep compliance predictions and laboratory results of independent test of the elastic Young modulus. The results show good agreement between the independent standard test and predicted values demonstrating the predictive and repeatability capabilities of the proposed methodology. Hypothesis tests further analyzed that the differences in the results from the simulation of the interconverted creep compliance and the independent standard test is only due to inherent statistical scatter for at least 4% of significance level for both pastes and all loading ages. The proposed methodology demonstrated to deliver not only dynamic characterization of cement pastes, but also the creep compliance in the time domain and the static secant modulus of cement pastes.
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- 2019
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12. Cultura e capoeira: vivências de jovens periféricos
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Francisco Evangelista and Elisângela Lambstein Franco de Moraes
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lcsh:LC8-6691 ,lcsh:Theory and practice of education ,lcsh:Special aspects of education ,diversidade étnica ,capoeira ,centro de referência de assistência social ,General Medicine ,cultura ,lcsh:LB5-3640 - Abstract
Resumo A investigação se dá acerca da cultura da Capoeira presente no cotidiano de jovens em situação de vulnerabilidade e, para tanto, o foco investigativo se concentra nos serviços de desenvolvimento e estabelecimento de vínculos realizado no CRAS (Centro de Referência de Assistência Social) em Santa Bárbara d’Oeste e nas atividades de capoeira que são desenvolvidas no mesmo bairro. A concentração da pesquisa está no desenvolvimento da educação social presente nas atividades, com o objetivo de reconhecer dentro do CRAS quais as propostas culturais de fortalecimento de vínculos, local onde se buscou encontrar a presença da capoeira. A apresentação se dá de maneira descritiva; a argumentação se fundamenta na análise, na crítica e na reflexão sobre os pareceres dos jovens e está fundamentada na teoria de Marilena Chaui. A capoeira ainda não está presente nesse espaço, contudo, está presente no bairro e acessível a todos, de forma gratuita e oferecida em uma escola estadual do bairro. Sabe-se que na capoeira o papel do Mestre de capoeira é uma referência positiva e que mobiliza a juventude para bons valores. Durante a pesquisa observaram-se as atividades culturais oferecidas no CRAS. Assim, conclui-se que a capoeira não faz parte desse rol de atividades, mas que pelas qualidades culturais e potenciais dos jovens, se implantada faria diferença positiva no trabalho e viria ao encontro do objetivo do desenvolvimento de vínculos. O desafio é reconhecer a capoeira como patrimônio brasileiro e, com o potencial cultural que a mesma proporciona, deveria estar presente nos espaços educativos brasileiros. Palavras-chave: Capoeira; Diversidade étnica; Centro de Referência de Assistência Social; Cultura. ABSTRACT This article presents an investigation about the Capoeira culture present in the daily life of vulnerable youths and, for that, the research focus is on the development and linkage services carried out at the CRAS (Social Assistance Reference Center) in Santa Bárbara d'Oeste and the capoeira activities that are developed in the same neighborhood; the focus of research is on the development of social education present in the activities, with the objective of recognizing within the CRAS the cultural proposals for strengthening ties, a place where the presence of capoeira was sought. The presentation is given in a descriptive way; the argument is based on analysis, criticism and reflection on the opinions of young people and is based on the theory of Marilena Chaui. Capoeira is not yet present in this space, however, it is present in the neighborhood and accessible to all, free of charge and offered at a state school in the neighborhood. It is known that in capoeira the role of the Capoeira Master is a positive reference and that mobilizes the youth for good values. During the research the cultural activities offered in CRAS were observed. Thus, it is concluded that capoeira is not part of this list of activities, but that by the cultural and potential qualities of young people if implemented would make a positive difference to work and would meet the goal of developing links. The challenge is to recognize capoeira as Brazilian patrimony and with the cultural potential that it provides and must be present in Brazilian educational spaces. Keywords: Capoeira; Ethnic diversity; Reference Center for Social Assistanc; Culture. RESUMEN La investigación se da acerca de la cultura de la Capoeira presente en el cotidiano de jóvenes en situación de vulnerabilidad y, para ello, el foco investigativo se concentra en los servicios de desarrollo y establecimiento de vínculos realizado en el CRAS (Centro de Referencia de Asistencia Social) en Santa Bárbara de Oeste y en las actividades de capoeira que se desarrollan en el mismo barrio; la concentración de la investigación está en el desarrollo de la educación social presente en las actividades, con el objetivo de reconocer dentro del CRAS cuáles son las propuestas culturales de fortalecimiento de vínculos, local donde se buscó encontrar la presencia de la capoeira. La presentación se da de manera descriptiva; la argumentación se fundamenta en el análisis, la crítica y la reflexión sobre los dictámenes de los jóvenes y está fundamentada en la teoría de Marilena Chaui. La capoeira aún no está presente en ese espacio, sin embargo, está presente en el barrio y es accesible a todos de forma gratuita, ofrecida por una escuela estatal del barrio. Se sabe que en la capoeira el papel del Maestro de Capoeira es una referencia positiva y que moviliza a la juventud hacia buenos valores. Durante la investigación se observaron las actividades culturales ofertadas en el CRAS. Así, se concluye que la capoeira no forma parte de ese grupo de actividades pero que, por las cualidades culturales y potenciales de los jóvenes, su implantación aportaría una diferencia positiva al trabajo y vendría al encuentro del objetivo de desarrollo de vínculos. El desafío es reconocer la capoeira como patrimonio brasileño y, por el potencial cultural que la misma proporciona, debería estar presente en los espacios educativos brasileños. Palabras clave: Capoeira; Diversidad étnica; Centro de Referencia de Asistencia Social; Cultura. DOI: http://dx.doi.org/10.22169/revint.v14i32.1615
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- 2019
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13. Multiscale aircraft fuselage fatigue analysis by the dual boundary element method
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Gilberto Gomes, Francisco Evangelista, and Thiago A.A. Oliveira
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Computer program ,business.industry ,Computer science ,Applied Mathematics ,Monte Carlo method ,General Engineering ,Structural engineering ,Square (algebra) ,Dual (category theory) ,Computational Mathematics ,Fuselage ,Limit state design ,business ,Damage tolerance ,Boundary element method ,Analysis - Abstract
This paper focuses on the multiscale fatigue life analysis of an aircraft fuselage panel in order to investigate the damage tolerance performance. The two-dimensional multiscale analyses were carried out under different levels of external loads and based on linear elastic fracture mechanics. For this, a micro model consisting of a square plate with a central circular hole and two cracks, from pre-established initial damages and subjected to uniaxial tension, was modelled using the computer program BemCracker2D–an academic computational package for crack growth analysis based on the dual boundary element method (DBEM). The objective is to compute the number of fatigue cycles for each load increment and relate them to their respective compliance in local micro elements. Then, the results were treated statistically with Monte Carlo simulation to ensure the integrity of the fuselage and, therefore, avoiding reaching a Limit State during the design lifespan. The main advantages of using the DBEM formulation implemented in BemCracker2D are easy pre- and post-processing, simplicity of meshing and satisfactory accuracy.
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- 2019
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14. A Probabilistic Approach in Fuselage Damage Analysis via Boundary Element Method
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Francisco Evangelista, Thiago A.A. Oliveira, and Gilberto Gomes
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020303 mechanical engineering & transports ,Materials science ,0203 mechanical engineering ,Fuselage ,business.industry ,Probabilistic logic ,Damage analysis ,02 engineering and technology ,Structural engineering ,021001 nanoscience & nanotechnology ,0210 nano-technology ,business ,Boundary element method - Abstract
This chapter presents a new alternative approach to the analysis of the fatigue life of aircraft fuselage parts considering the compliance of internal elements to replace the classical model of critical crack size. In this case, from a global–local analysis using the boundary element method (BEM), induced stresses at a macro model, and their effects on micro models are evaluated. The BEM enables efficient simulations of the propagation of initial defects to assess the damage tolerance. For this purpose, computational techniques were developed that allowed evaluating these models, through a probabilistic treatment to assess damage tolerance and fatigue life. Finally, this technique is shown as an alternative to ensure the integrity and proper operation of fuselage panels avoiding reaching a Limit State during its projected lifespan.
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- 2021
15. Shelf Life - Managing Building Material in a Warehouse
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Alexandra Priscilla Tregue Costa, David Barbosa de Alencar, and Francisco Evangelista Pimentel Neto
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Engineering ,business.industry ,Building material ,engineering.material ,Shelf life ,business ,Construction engineering ,Warehouse - Published
- 2019
- Full Text
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16. Number of tests and corresponding error in concrete fatigue
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José J. Ortega, Xiaoxin Zhang, Rena C. Yu, Nelson Afanador-García, Manuel Tarifa, Gonzalo Ruiz, Elisa Poveda, and Francisco Evangelista
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Mechanical Engineering ,0211 other engineering and technologies ,Probabilistic logic ,Fatigue testing ,02 engineering and technology ,Industrial and Manufacturing Engineering ,Possibility distribution ,Set (abstract data type) ,020303 mechanical engineering & transports ,0203 mechanical engineering ,Mechanics of Materials ,Modeling and Simulation ,Resampling ,021105 building & construction ,Applied mathematics ,General Materials Science ,Weibull distribution ,Mathematics - Abstract
Concrete fatigue presents probabilistic behaviour evidenced by the wide scatter of cycles to failure under the same conditions. Experimentally-fitted probabilistic distributions have an error in terms of fatigue life that depends on the number of tests. Through statistical resampling, this relationship has been obtained for the Weibull probabilistic distribution fitted to a set of 100 tests and with two additional parameter combinations. Results for low to high cycle fatigue help to obtain design fatigue probability curves or the necessary number of tests for a given admissible error. Their applicability extends to any other phenomenon that follows the Weibull distribution with similar parameters.
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- 2018
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17. João Bosco: percurso histórico de sua práxis educativa e social
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Francisco Evangelista and Elisete Soave Vianna
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General Medicine - Abstract
O presente texto se propõe a fazer uma análise da pessoa e figura de João Bosco com o objetivo de refletir sobre essa personalidade intrigante, que suscita tantos comentários, definições e histórias, mas que é, sem dúvida, o centro de toda a filosofia e práxis na comunidade salesiana. O que se propõe é ir além do santo “Dom Bosco”, como é denominado João Bosco nessa comunidade, e olhar para o cidadão de sua comunidade, para o religioso fervoroso, para o educador social, enfim, para essas facetas de João Bosco em seu tempo e local, em seu contexto. O texto faz uma apresentação histórica e reflete sobre a atuação do padre italiano no século XIX, desde sua infância humilde e pobre de camponês até sua dedicação no período de formação para ser padre. Apresenta sua atuação inicial com os meninos que vagavam pelas ruas e com aqueles que se encontravam nas prisões de Turim. O texto analisa também a relação do padre educador com a política e conclui com uma reflexão sobre o legado de João Bosco, isto é, a Educação Salesiana e o Sistema Preventivo hoje. Palavras-chave: Educação Salesiana. História da Educação Salesiana. João Bosco. João Bosco: historical path of his educational and social praxis AbstractThe present text proposes to make an analysis of the person and figure of John Bosco aiming to reflect on this intriguing personality, which gives rise to so many definitions, stories and commentaries, but who is undoubtedly the center of all philosophy and praxis in the Salesian community. What is proposed is to go beyond the holy “Don Bosco”, as John Bosco is called in that community, and look to the citizen of his community, to the fervent religious and to the social educator, that is, to these facets of John Bosco in his time and place, in his context. The text gives a historical presentation and reflects on the performance of the Italian priest in the nineteenth century; of his humble and poor childhood and of a peasant and his dedication in the period of formation to become a priest. The text also presents its initial performance together with the boys who wandered the streets and those who were in the prisons of Turin. It analyzes the relationship of the priest educator with politics and concludes with a reflection on the legacy of John Bosco, that is: Salesian Education and the preventive system today. Keyeords: Salesian Education. History of Salesian Education. John Bosco. Juan Bosco: recorrido histórico de su praxis educativa y social ResumenEl presente texto se propone hacer un análisis de la persona y figura de Juan Bosco con el objetivo de reflexionar sobre esa personalidad intrigante, que suscita tantas definiciones, historias, comentarios, pero que es sin duda el centro de toda filosofía y praxis en la comunidad salesiano. Lo que se propone es ir más allá del santo “Don Bosco”, como es llamado Juan Bosco en esa comunidad, y mirar al ciudadano de su comunidad, al religioso fervoroso, para el educador social, en fin, para esas facetas de Juan Bosco en su tiempo y lugar, en su contexto. El texto hace una presentación histórica y reflexiona sobre la actuación del sacerdote italiano en el siglo XIX; desde su infancia humilde y pobre, de un campesino y su dedicación en el período de formación para ser sacerdote. Presenta su actuación inicial junto a los niños que vagaban por las calles y las que se encontraban en las prisiones de Turín. El texto analiza, también, la relación del padre educador con la política y concluye con una reflexión sobre el legado de Juan Bosco, es decir: la educación salesiana y el sistema preventivo hoy. Palabras clave: Educación Salesiana. Historia de la Educación Salesiana. Juan Bosco.
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- 2018
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18. Machine learning RBF-based surrogate models for uncertainty quantification of age and time-dependent fracture mechanics
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Iago Freitas de Almeida and Francisco Evangelista Junior
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Polynomial ,Generalization ,Computer science ,business.industry ,Mechanical Engineering ,Monte Carlo method ,Probabilistic logic ,Machine learning ,computer.software_genre ,Data point ,Mechanics of Materials ,General Materials Science ,Radial basis function ,Artificial intelligence ,Uncertainty quantification ,business ,computer ,Random variable - Abstract
This paper proposes a machine learning strategy using radial basis function (RBF) as surrogate models for uncertainty quantification of age and time-dependent fracture mechanics problems. The RBF surrogate models are trained to replace the time-consuming evaluations of the mapping integral of the time-dependent energy release rate. The probabilistic problem considers input random variables of geometry, loading, and material parameters for a concrete plate section with the presence of an initial surface crack. The performance of the RBF surrogates was evaluated through cross-validation and Monte Carlo reference solutions that expensively evaluated the integrals. The results of mean square errors and the Kolmogorov-Smirnov goodness-of-fit tests on the predicted probability and cumulative density functions show that, the RBF surrogates reached good accuracy even for a small training set size, rather than second-order polynomial models which could reasonably perform only for bigger training set sizes. The RBF surrogates accurately predict even long-tail distributions for farther prediction times with relatively small training sets. The proposed RBF surrogate models presented the generalization capabilities to predict thousands of unseen data points from Monte Carlo simulations and successfully assess the uncertainty quantification of the time-dependent energy release rate.
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- 2021
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19. Investigation of the notch angle in hydraulic fracturing using XFEM
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Edel R. Martínez, Márcio Muniz de Farias, and Francisco Evangelista Junior
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0209 industrial biotechnology ,Discretization ,Mechanical Engineering ,Applied Mathematics ,General Engineering ,Aerospace Engineering ,Fracture mechanics ,02 engineering and technology ,Mechanics ,Industrial and Manufacturing Engineering ,Finite element method ,020901 industrial engineering & automation ,Hydraulic fracturing ,Discontinuity (geotechnical engineering) ,Automotive Engineering ,Geology ,Stress intensity factor ,Tight gas ,Extended finite element method - Abstract
This paper analyzes the initiation and propagation of hydraulic fracturing by nonlinear numerical modeling. A notch located at the wellbore stimulates hydraulic fracturing. The notch has a pivotal role in hydraulic fracturing. There is evidence that the notch can affect the required fluid pressure and the fracture propagation and velocity. Therefore, it has been associated with the effectiveness of hydraulic fracturing in tight gas reservoirs. The objective of this study is to explore the effect of the notch angle on hydraulic fracturing. Models in two- and three dimensions are presented and analyzed. These models are used to find the breakdown pressure and stress intensity factors, respectively. The numerical approximation of hydraulically driven fracture propagation is based on the extended finite element method (XFEM). XFEM enriches finite elements and nodes at elements intersected by the crack during the crack propagation. XFEM reproduces the discontinuity in the displacement domain without the discretization of this property directly in the mesh. Therefore, the generated mesh is independent of the crack propagation. The accuracy of the numerical approach is validated by reproducing laboratory-scale hydraulic fracturing tests and comparing results.
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- 2019
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20. SOCIEDADE DO CONHECIMENTO: O uso das TIC por docentes e as novas articulações de saberes educacionais no sudeste do Pará
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Maria Fernanda Calil Angelini, Maria Josilene Fontinele Rocha, Karina Donizete Martins, and Francisco Evangelista
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Ensino e aprendizagem ,Formação docente ,Polymers and Plastics ,lcsh:Journalism. The periodical press, etc ,lcsh:PN4699-5650 ,Prática docente ,Tecnologias da informação e da comunicação ,lcsh:P87-96 ,General Environmental Science ,lcsh:Communication. Mass media - Abstract
O presente estudo tem o propósito verificar a adesão dos docentes e os entraves na utilização das TIC no processo ensino e aprendizagem numa IES privada, contribuindo para a criação de novas práticas pedagógicas ou de uma ciberpedagogia confrontando com o moduz operandi na docência. A pesquisa utilizou-se de reuniões de grupos e aplicação de questionário para professores dos cursos de Administração, Biomedicina, Contábeis, Direito, Enfermagem, Serviço Social e Zootecnia. Os dados foram interpretados por meio do círculo hermenêutico dialético (CHD). Os sentidos extraídos das falas dos docentes apontam como resultados preliminares que a TIC estimula o estudo, otimiza tempo e trabalho, favorece a autonomia do estudante e a responsabilidade. PALAVRAS-CHAVE: Ensino e aprendizagem; Tecnologias da informação e da comunicação; Prática docente; Formação docente. ABSTRACT The present study has the purpose of verifying the adherence of teachers and the obstacles to the use of ICT in the teaching and learning process in a private HEI, contributing to the creation of new pedagogical practices or a cyberpedagogy confronting the moduz operandi in teaching. The research used group meetings and questionnaire application for teachers of the courses of Administration, Biomedicine, Accounting, Law, Nursing, Social Service and Zootechnics. The data were interpreted through the dialectical hermeneutic circle (CHD). The senses extracted from the teachers' statements point as preliminary results that ICT stimulates the study, optimizes time and work, favors student autonomy and responsibility. KEYWORDS: Teaching and learning; Information and communication Technologies; Teaching practice; Teacher training. RESUMEN El presente estudio tiene el propósito de verificar la adhesión de los docentes y los obstáculos a la utilización de las TIC en el proceso de enseñanza y aprendizaje en una IES privada, contribuyendo a la creación de nuevas prácticas pedagógicas o de una ciberpedagogía confrontando con el modesto operandi en la docencia. La investigación utilizó reuniones de grupos y aplicación de cuestionario para profesores de los cursos de Administración, Biomedicina, Contable, Derecho, Enfermería, Servicio Social y Zootecnia. Los datos fueron interpretados por medio del círculo hermenéutico dialéctico (CHD). Los sentidos extraídos de las palabras de los docentes apuntan como resultados preliminares que la TIC estimula el estudio, optimiza tiempo y trabajo, favorece la autonomía del estudiante y la responsabilidad. PALABRAS CLAVE: Enseñanza y aprendizagem; Tecnologías de la información y la comunicación; Pratica docente; Formación docente.
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- 2019
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21. A novel continuum damage model to simulate quasi-brittle failure in mode I and mixed-mode conditions using a continuous or a continuous-discontinuous strategy
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José Fabiano Araújo Moreira and Francisco Evangelista
- Subjects
Materials science ,Continuum (measurement) ,Applied Mathematics ,Mechanical Engineering ,0211 other engineering and technologies ,Fracture mechanics ,02 engineering and technology ,Mechanics ,Dissipation ,Condensed Matter Physics ,Mixed mode ,Finite element method ,020303 mechanical engineering & transports ,Brittleness ,0203 mechanical engineering ,General Materials Science ,Polygon mesh ,Softening ,021101 geological & geomatics engineering - Abstract
This paper formulated and implemented a novel local continuum damage model to be used with a continuous or a continuous-discontinuous strategy to simulate crack growth in quasi-brittle failure for mode I and mixed-mode conditions. The damage model is based on an evolution law using only physical parameters, which can be obtained through fracture and resistance tests without the need for further calibration. The local energy dissipation is controlled through regularization by the fracture energy and element length ensuring that different mesh densities dissipated the same energy during the damage evolution. The proposed damage model is employed in a finite element framework in two strategies: (i) a continuous strategy in which only the continuum damage model is used to predict crack propagation failure; and (ii) a continuous-discontinuous strategy in which a discontinuous enrichment is used to insert a crack within the elements after the total damage state is reached with no ad-hoc threshold value for the transition from continuous to the discontinuous approach. Comprehensive validation is demonstrated through comparisons with experimental results for various types of tests in mode I and mixed-mode conditions: single edge notch beam, unnotched four-point beam, anti-symmetric four-point shear beam, and double-edge-notched specimen. The results demonstrated that the proposed damage model and both strategies successfully simulated the crack propagation and failure of all simulated tests. Good agreement with the experimental results is observed for the crack path, maximum load, and entire load–displacement softening curves with coarser meshes than other models of the literature. Furthermore, the 3D results of the mixed-mode double-edge-notched specimen show that the proposed model provided good results even with coarser meshes using 16 times fewer elements than recent and similar results from the literature.
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- 2020
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22. A global–local strategy with the generalized finite element framework for continuum damage models
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Gelson de Sousa Alves, Guilherme Oliveira Ferraz de Paiva, José Fabiano Araújo Moreira, and Francisco Evangelista
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State variable ,Discretization ,Computer science ,Mechanical Engineering ,Computational Mechanics ,Degrees of freedom (statistics) ,General Physics and Astronomy ,Monotonic function ,Fracture mechanics ,010103 numerical & computational mathematics ,01 natural sciences ,Finite element method ,Computer Science Applications ,010101 applied mathematics ,Nonlinear system ,Mechanics of Materials ,Applied mathematics ,Polygon mesh ,0101 mathematics - Abstract
This paper presents a global–local strategy with the generalized finite element framework to simulate structural failure through nonlinear continuum damage models. The global problem is the scale of the structure which is discretized with relative coarse meshes while the local problem is a subdomain of interest of the global problem where refined meshes can be used to simulate localized crack growth. The proposed method uses the converged nonlinear local problem solution as enrichment functions for the global problem which is considered linear with no need for an iterative procedure to solve it. The strategy is validated and compared with reference solutions and experimental results with crack propagation in mode I and mixed-mode conditions in monotonic tests of quasi-brittle materials. The results show that the method has the capability to transfer the kinematic effects and the damage state variable that occurs in the local problem to accurately predict the global structural behavior under the damage process. The proposed strategy demonstrated the capability to accurately predict the experimental crack paths and load–displacement curves with a reduced number of iterations and degrees of freedom in relation to the conventional finite element and generalized finite element methods.
- Published
- 2020
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23. Profile of internal relative humidity and depth of drying in cementitious materials containing superabsorbent polymer and nano-silica particles
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Eugênia Fonseca da Silva, Paulo F.O. Reis, and Francisco Evangelista
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Cement ,Materials science ,Diffusion ,0211 other engineering and technologies ,020101 civil engineering ,02 engineering and technology ,Building and Construction ,Thermal diffusivity ,0201 civil engineering ,Superabsorbent polymer ,021105 building & construction ,Nano ,General Materials Science ,Relative humidity ,Cementitious ,Composite material ,Civil and Structural Engineering - Abstract
This paper aims to characterize and model the internal relative humidity profiles and drying depth in hardened cement pastes containing superabsorbent polymers (SAP) and nano-silica (NS) particles. Five different cement pastes were considered with the incorporation of SAP, NS, and simultaneous SAP and NS to reference mixtures with different water/cement ratios. Characterization of mass loss history, the evolution of the diffusion coefficient, and modeling of relative humidity profiles were performed for the five cement pastes in three different ages and three drying times. This paper also proposes a low-cost apparatus to monitor the mass loss history of thin specimens of cement pastes. The characterization was determined by the drying process with a gradual variation of the RH environment from 100% to 43%. The diffusion coefficient and the profile of the internal relative humidity through the drying depth in specimens of different ages and drying periods were estimated by the mass loss evolution. The results show that the pastes containing SAP presents a higher mass loss, higher diffusivity and deeper drying depths for all ages and drying periods investigated. Although the incorporation of NS to the reference paste improved their performance, this improvement is observed only in 28-day old pastes with SAP.
- Published
- 2020
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24. Guia para implantação de sistema de gestão da qualidade em setores de engenharia clínica de hospitais – Atendimento aos requisitos das normas ABNT NBR ISO 9001:2015 e ABNT NBR 15943:2011
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Leal, Fábio Francisco Evangelista, Oliveira, Eduardo Jorge Valadares, Holsbach, Léria Rosane, and Oliveira, Vivian Cardoso de Morais
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Engenharia clínica ,Equipamentos médico-hospitalares ,MEDICINA [CIENCIAS DA SAUDE] ,Technology Management in Health ,Quality Management System ,Sistema de Gestão da Qualidade ,Gestão de Tecnologias de Saúde ,Hospital Engineering Equipment ,Clinical Engineering - Abstract
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2019-08-28T17:42:21Z No. of bitstreams: 1 PDF - Fábio Francisco Evangelista Leal.pdf: 12797390 bytes, checksum: 4ad15757335ba4759afa6b9ef8a1146e (MD5) Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2019-10-10T14:05:27Z (GMT) No. of bitstreams: 1 PDF - Fábio Francisco Evangelista Leal.pdf: 12797390 bytes, checksum: 4ad15757335ba4759afa6b9ef8a1146e (MD5) Made available in DSpace on 2019-10-10T14:05:27Z (GMT). No. of bitstreams: 1 PDF - Fábio Francisco Evangelista Leal.pdf: 12797390 bytes, checksum: 4ad15757335ba4759afa6b9ef8a1146e (MD5) Previous issue date: 2018-12-21 The objective of this work was to create a managerial practice tool that could assist Clinical Engineering professionals in performing their activities in hospital units, through the implementation of a Quality Management System applied to Health Technology Management. In order to achieve this objective, a guide for the implementation of the Quality Management System (QMS) was developed based on the ISO 9001: 2015 standard and on compliance with the provisions of the ABNT NBR 15943: 2011 standard, which addresses the guidelines for a health equipment management program. This Guide aims to assist hospital health professionals in the use of internationally accepted and recognized practices for quality management, as well as the application of good health equipment management practices, with the purpose of improving the quality of processes and engineering services in hospitals. A literature review was carried out to collect specific knowledge related to quality management and health equipment management. Then, for the development of the methodology, all the requirements of the two mentioned standards were studied and analyzed and a template tool was used to develop the proposed Guide, resulting in the elaboration and use of 52 documents, separated in 19 appendices and 33 attachments. All the documents prepared were correlated, through a single document, the Quality Manual (Model). The Quality Manual developed, in addition to bringing a step by step to the implementation of t he quality management system, also brings to the reader explanations about the requirements of ISO 9001: 2015 and practical examples of activities related to the requirements of the ABNT standard NBR 15943: 2011. O objetivo desse trabalho foi de criar uma ferramenta de prática gerencial que pudesse auxiliar os profissionais de engenharia clínica na realização de suas atividades em unidades hospitalares, através da implantação de um sistema de gestão da qualidade aplicado ao gerenciamento de tecnologias em saúde. Para alcançar esse objetivo desenvolveu-se nesse trabalho um Guia para orientação na implantação de Sistema de Gestão da Qualidade - SGQ baseado na norma ABNT NBR ISO 9001:2015 e no atendimento às disposições da norma ABNT NBR 15943:2011, a qual trata das diretrizes para um programa de gerenciamento de equipamentos para a saúde. Esse Guia pretende auxiliar os profissionais de saúde de hospitais na utilização de práticas internacionalmente aceitas e reconhecidas para a gestão da qualidade, assim como a aplicação de boas práticas de gerenciamento de equipamentos de saúde, com intuito de melhoria da qualidade de processos e serviços de engenharia clínica nos hospitais. Foi realizada uma revisão da literatura para levantamento de conhecimentos específicos ligados à gestão da qualidade e ao gerenciamento de equipamentos para saúde. Em seguida, para desenvolvimento da metodologia foram estudados e analisados todos os requisitos das duas normas citadas e utilizada uma ferramenta modelo (template) para desenvolvimento do Guia proposto, resultando na elaboração e utilização de 52 documentos, separados em 19 apêndices e 33 anexos. Todos os documentos elaborados foram correlacionados, através de um único documento, o Manual da Qualidade (Modelo). O Manual da Qualidade desenvolvido, além de trazer um passo a passo para a implantação do sistema de gestão da qualidade, também traz ao leitor explicações sobre os requisitos da Norma ABNT NBR ISO 9001:2015 e exemplos práticos de atividades relacionadas aos requisitos da norma ABNT NBR 15943:2011.
- Published
- 2018
25. Geração de Mapas de Danos de Formação de Manchas em Fachadas a Partir dos Métodos de DSM e PDI, e Utilização de VANT
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Francisco Evangelista Junior, Lenildo Santos da Silva, Carlos Mariano Melo Júnior, and Antônio Alberto Nepomuceno
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Digital Photogrammetry ,Fotogrametria digital ,Computer science ,business.industry ,Point cloud ,Stereo matching ,Maps of damages ,Points of cloud ,Tyche (hypothetical planet) ,lcsh:Urban groups. The city. Urban sociology ,Nuvem de pontos ,Visual inspection ,Damages ,Computer vision ,lcsh:HT101-395 ,Artificial intelligence ,lcsh:Architecture ,business ,Mapas de danos ,Digital image processing ,Processamento digital de Imagens ,lcsh:NA1-9428 - Abstract
The aim of this study was to apply a methodology for automatic generation of maps of damages in orthoimages of façades, using UAVs to capture the photographs. The generation of maps of damages aims to assist in the visual inspection method used in activities of maintenance, restoration or intervention in buildings. Using the dense stereo matching (DSM) method, geometric models of buildings have been generated by the point cloud in the PhotoScan program for obtaining orthoimages. After this step, the orthoimages were submitted to generation of maps of damages of staining in Tyche program, which mapped and quantified in percentage terms these defects. The results of the maps of damage were also classified qualitatively. The application of UAV proved to be an efficient tool for façade inspection activity and for capturing images to be used by DSM. The generation of maps of damages by Tyche proved also effective, however was established that the user interaction was important to achieve the expected results., O objetivo deste trabalho foi aplicar uma metodologia para geração automática de mapas de danos em ortoimagens de fachadas de edifícios, utilizando-se VANT para a captura das fotografias. A geração de mapas de danos visa auxiliar na inspeção visual, método empregado nas atividades de recuperação manutenção ou intervenção em edifícios. Utilizando a técnica de dense stereo matching (DSM), modelos geométricos de edifícios foram gerados por nuvem de pontos no programa PhotoScan para a obtenção de ortoimagens. Após esta etapa, as ortoimagens foram submetidas à etapa de geração de mapas de danos de manchas escuras no Programa Tyche, que mapeou e quantificou percentualmente estas manifestações patológicas. Os resultados dos mapas de danos foram classificados também qualitativamente. A aplicação de VANT demonstrou ser uma ferramenta eficiente para a atividade de inspeção de fachadas e para a captura de imagens a serem utilizadas por meio da DSM. A geração de mapas de danos pelo Tyche demonstrou ser também eficaz, no entanto a interação do usuário mostrou-se importante para alcançar os resultados esperados.
- Published
- 2018
26. Generating of damage maps of building façades through digital image processing captured by drones and use of digital photogrammetry
- Author
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Carlos Mariano Melo Júnior, Francisco Evangelista Junior, Antônio Alberto Nepomuceno, Lenildo Santos da Silva, and Conselho Nacional de Desenvolvimento Científico e Tecnológico
- Subjects
Fachadas (Arquitetura) ,Geography, Planning and Development ,0211 other engineering and technologies ,Processamento digital de imagens ,02 engineering and technology ,010502 geochemistry & geophysics ,01 natural sciences ,Mapas de danos de fachadas ,Dense stereo matching ,Processamento digital de Imagens ,021105 building & construction ,Digital image processing ,Maps of damages of façades ,Processamento de imagens - técnicas digitais ,0105 earth and related environmental sciences - Abstract
Resumo O objetivo deste trabalho foi aplicar uma metodologia para geração automática de mapas de danos em ortoimagens de fachadas de edifícios, utilizando-se veículo aéreo não tripulado (Vant) para a captura das fotografias. A geração de mapas de danos visa auxiliar na inspeção visual, método empregado nas atividades de recuperação, manutenção ou intervenção em edifícios. Utilizando a técnica de dense stereo matching (DSM), modelos geométricos de edifícios foram gerados por nuvem de pontos no programa PhotoScan para a obtenção de ortoimagens. Após essa etapa, as ortoimagens foram submetidas à etapa de geração de mapas de danos de manchas escuras no Programa Tyche (2015), que mapeou e quantificou percentualmente essas manifestações patológicas. Os resultados dos mapas de danos foram classificados também qualitativamente. A aplicação de Vant demonstrou ser uma ferramenta eficiente para a atividade de inspeção de fachadas e para a captura de imagens a serem utilizadas por meio da técnica DSM. A geração de mapas de danos pelo Tyche (2015) demonstrou ser também eficaz, no entanto a interação do usuário mostrou-se importante para alcançar os resultados esperados. Abstract The aim of this study was to apply a methodology for automatic generation of maps of damages in orthoimages of façades, using UAVs to capture the photographs. The generation of maps of damages aimed to assist in the visual inspection method used in activities of maintenance, restoration or intervention in buildings. Using the dense stereo matching (DSM) method, geometric models of buildings weren generated by the point cloud in the PhotoScan program for obtaining orthoimages. After this step, the orthoimages were submitted to generation of maps of damages of staining in Tyche (2015) software, which mapped and quantified in percentage terms these defects. The results of the maps of damage were also classified qualitatively. The application of UAV proved to be an efficient tool for façade inspection activity and for capturing images to be used by DSM. The generation of maps of damages by Tyche (2015) proved also effective, however it was verified that the user interaction was important to achieve the expected results.
- Published
- 2018
27. ANTONIO GRAMSCI E A EDUCAÇÃO (ESCOLA UNITÁRIA)
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Francisco Evangelista and Elcio Arestides de Mattos da Silva
- Subjects
lcsh:LC8-6691 ,Antonio Gramsci. Educação. Escola unitária ,lcsh:Special aspects of education ,lcsh:L ,lcsh:Education - Abstract
A educação não está restrita à sala de aula ou a qualquer espaço físico pré-determinado. Ela acontece a todo o momento. Muitas vezes, sem nos darmos conta, se educa, até sem palavras. A escola unitária configura-se numa escola que leve em conta as faixas etárias e que não exclua ninguém do processo educativo. Tal escola considera a todos no seu todo, sem desprezar os diversos aspectos da dimensão humana. O objetivo desse artigo, à luz das contribuições de Antonio Gramsci é discutir o papel da escola e a possibilidade da formação do homem omnilateral. Nesse sentido, concorda-se com Gramsci quanto a possibilidade e efetividade da escola unitária, objeto que precisa estar na agenda brasileira, quando se pensa em emancipação social.
- Published
- 2015
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28. Apresentação do Dossiê 200 Anos de Dom Bosco (p. 15-18)
- Author
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Francisco Evangelista
- Subjects
General Medicine - Published
- 2017
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29. MÉTODO DOS ELEMENTOS FINITOS GENERALIZADOS COM ENRIQUECIMENTO DE INTERFACE PARA MATERIAIS COMPÓSITOS
- Author
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Alves, Gelson de Sousa and Junior, Francisco Evangelista
- Abstract
Resumo. Este artigo tem como objetivo apresentar uma formulação não convencional do método dos elementos finitos (MEF). O método dos elementos finitos generalizados (MEFG) foi formulado a fim de melhorar a aproximação dos problemas de valor de contorno com soluções descontínuas devido a diferentes interfaces de materiais. Foi apresentado uma técnica levando em consideração a interface do material em compósitos sem a correspondência da malha de elementos finitos com o contorno dos diferentes materiais nos membros estruturais: chapas com dois materiais e compósitos heterogêneos (matriz e inclusões). Os resultados foram comparados com soluções simuladas pelo MEF, mostrando a eficiência do método e modelo proposto. A estratégia demonstrou potencial para resolver problemas com gradiente descontínuo causado pela interface material. Keywords: MEF, MEFG, Interface, Materiais Compósitos
- Published
- 2017
30. MODELO BIDIMENSIONAL CONTÍNUO-DESCONTÍNUO DE FALHA PARA MATERIAIS QUASE-FRÁGEIS
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Moreira, José Fabiano Araújo and Junior, Francisco Evangelista
- Abstract
Resumo. Esta pesquisa teve como objetivo formular e implementar um modelo de danocontínuo-descontínuo (com transição para fratura), por meio do Método dos Elementos Finitos Generalizados, capaz de predizer falhas em estruturas de materiais quase-frágeis. A mais importante contribuição é a criação de um modelo capaz de simular numericamente a resistência de membros estruturais sob falhas de maneira eficiente, baseado em uma lei de evolução de dano que utiliza apenas parâmetros físicos, que podem ser obtidos por meio de ensaios de resistência e fratura, sem a necessidade de calibração adicional do modelo. A validação do mesmo se deu por intermédio da comparação com resultados experimentais retirados do ensaio de flexão em três pontos em viga com entalhe central. Os resultados obtidos comprovaram a eficiência e acurácia do modelo na previsão do comportamento de ruptura. O modelo consegue fornecer resultados com uma precisão equivalente à de outros modelos encontrados na literatura, porém utilizando um número bem reduzido de elementos na malha.Palavras Chave: Mecânica do Dano Contínuo, Modelo de Zona Coesiva, Materiais quasefrágeis, Propagação de trincas, MEFG.
- Published
- 2017
31. QUANTIFICAÇÃO DA INCERTEZA DA VIDA DE PLACAS DE AÇO SOB À FADIGA VIA POLINÔMIOS DE HERMITE
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García, Nelson Afanador and Junior, Francisco Evangelista
- Abstract
O objetivo deste trabalho é quantificar a incerteza no número de ciclos para falha por fadiga de componentes entalhados por meio do uso de polinômios de Hermite multidimensionais.A metodologia deformação-vida de estimativa de vida à fadiga é adotada e considera-se como variáveis aleatórias as propriedades do material e os níveis do carregamento aplicado.O uso de séries de polinômios de Hermite multidimensionais permitiu a predição da aleatoriedade do vetor de saída (número de ciclos para falha). Demonstra-se que um polinômio de Hermite multidimensional é capaz de estimar de forma adequada a propagação das incertezas associadas às variáveis de entrada. Os resultados sugerem que incertezas nas propriedades do material e no carregamento podem resultar em variações significativas no número de ciclos para falha de componentes sujeitos à falha por fadiga.Keywords: Polinômio de Hermite Multidimensional, Fadiga, Quantificação da incerteza, Metodologia deformação-vida
- Published
- 2017
32. META MODELOS PARA QUANTIFICAÇÃO DA INCERTEZA DA PREDIÇÃO DE FADIGA DE BAIXO CICLO EM MEMBROS ESTRUTURAIS
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de Almeida, Iago Freitas and Junior, Francisco Evangelista
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Resumo. Este artigo tem como objetivo implementar M ), onde a partir de variáveis de entrada a resposta estrutural do sistema é determinada a partir de uma superfície de resposta ajustada por meio dos parâmetros do Meta modelo. A resposta do sistema estrutural é construída por uma superfície de resposta que modela a vida de fadiga de membros estruturais submetidos a carregamentos aleatórios com amplitude variável. É demostrada para análise de diferentes técnicas de amostragem, tais como hipercubo latino, sequência de sobol e experimento fatorial para a construção do meta modelo eficiente na predição da incerteza da vida de fadiga pelo modelo implementado. xˆPalavras-chaves: Meta modelo, Regressão Polinomial, fadiga de baixo ciclo, Quantificação da Incerteza.
- Published
- 2017
33. Analysis of the influence of viscoelasticity on the occurrence of unstable crack propagation using the R-Curve
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Francisco Evangelista Junior, Fernando Martins Ribeiro Filho, and Amanda Araújo da Silva
- Subjects
Materials science ,Fracture mechanics ,Mechanics ,Viscoelasticity - Published
- 2017
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34. EVOLUÇÃO DA PREDIÇÃO DE CARGA DE RUPTURA DE PERFIS DE AÇO EM CHAPA DOBRADA CONECTADAS POR PARAFUSOS CONSIDERANDO O FENÔMENO
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Jéssica Ferreira Borges, Valdeir Francisco de Paula, Luciano M. Bezerra, and Francisco Evangelista
- Published
- 2017
- Full Text
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35. IMPLEMENTAÇÃO BIDIMENSIONAL DO MODELOS DE ZONA COESIVA PPR POR MEIO DO MÉTODO DOS ELEMENTOS FINITOS GENERALIZADOS
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Francisco Evangelista Junior and José Fabiano Araújo Moreira
- Published
- 2017
- Full Text
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36. Africanidades, afrodescendências e educação
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Rubia Cristina Cruz, Lucineia Chrispim Pinho Micaela, and Francisco Evangelista
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- 2017
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37. Development of Digital Image Correlation tool to determine displacements and strains in mechanical testing
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Francisco Evangelista Junior and Ellon Bernardes de Assis
- Subjects
Digital image correlation ,business.industry ,Computer science ,Computer vision ,Development (differential geometry) ,Artificial intelligence ,business - Published
- 2017
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38. Finite Element Modeling of heterogeneous beams considering the viscoelasticity of the cement paste and the elasticity of aggregates
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Fernando Martins Ribeiro Filho, Amanda Araújo da Silva, Francisco Evangelista Junior, and Fabiano Campos Macedo
- Subjects
Materials science ,Elasticity (economics) ,Composite material ,Cement paste ,Viscoelasticity ,Finite element method - Published
- 2017
- Full Text
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39. Three-dimensional cohesive zone model for fracture of cementitious materials based on the thermodynamics of irreversible processes
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Jeffery R. Roesler, Sergio Persival Baroncini Proença, and Francisco Evangelista
- Subjects
Materials science ,CONCRETO ,Tension (physics) ,Mechanical Engineering ,Constitutive equation ,Stiffness ,Thermodynamics ,Compression (physics) ,Cohesive zone model ,Mechanics of Materials ,Damage mechanics ,medicine ,Fracture (geology) ,General Materials Science ,Cementitious ,medicine.symptom ,Composite material - Abstract
This paper presents the formulation and implementation of a new 3-D cohesive zone element (CZM) with mode I traction-displacement laws for cementitious materials. The separation model is based on a damage mechanics framework which accounts for the thermodynamics of irreversible processes. Unlike many existing cohesive models, this proposed irreversible cohesive constitutive model prevents previous cohesive states from occurring on the fracture surface upon external or local unloading through a scalar damage parameter. In the proposed formulation, the interpenetration upon compressive loading is also avoided without any special contact algorithm. The CZM formulation and implementation are first verified using a 3-D uniaxial tension problem under tension and compression loading, unloading, and reloading. The proposed approach converged with higher values of the penalty stiffness without generating instabilities or oscillations in the traction profile. The damage-based evolution cohesive law was characterized by physically-defined fracture parameters derived from standard fracture tests for concrete materials (KIC, CTODC, Gf, and GF) and tensile strength ( f t ′ ). The proposed model was validated by predicting the fracture behavior of SEN(B) specimen for a wide range of concrete materials including plain concrete mixtures containing virgin aggregates and recycled concrete aggregates (RCA), and concrete with RCA and fibers or nano-silica particles. The proposed model was further validated by predicting the load–deflection of 1.8 m × 1.8m by 0.15 m concrete slabs experimentally tested on a soil foundation. The 3-D damage-based cohesive zone model simulations with bilinear softening, defined by small-scale fracture tests, were able to predict the concrete slab response and load capacity.
- Published
- 2013
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40. Un enfoque de polinomio de expansión de caos al análisis de la incerteza en elementos estructurales visco elásticos
- Author
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Francisco Evangelista and Nelson Afanador Garcia
- Subjects
lcsh:TN1-997 ,Polinomios de expansión de caos ,lcsh:T ,Philosophy ,General Engineering ,Viscoelasticidad ,Viscoelasticity ,02 engineering and technology ,Stochastic analysis ,lcsh:Technology ,01 natural sciences ,módulo de relajación ,010101 applied mathematics ,020303 mechanical engineering & transports ,Relaxation modulus ,0203 mechanical engineering ,relaxation modulus ,62 Ingeniería y operaciones afines / Engineering ,Polynomial chaos expansions ,Análisis estocástico ,0101 mathematics ,Humanities ,lcsh:Mining engineering. Metallurgy - Abstract
La propagación de la incerteza en sistemas mecánicos a través de modelos de cálculo fue analizado en este artículo por series de polinomios estocásticos de variables aleatorias estandarizadas llamados Polinomios de expansión de caos. Este artículo tuvo como objetivo simular la propagación de la incerteza en modelos mecánicos más complejos tales como estructuras visco elásticas el cual implica caracterización de parámetros dependientes del tiempo de materiales, interconversión de funciones matemáticas a través de transformada de Laplace, y resolución de la ecuación constitutiva mediante integrales de convolución. La aplicación de series de polinomios Hermite multidimensionales permitió la predicción de la aleatoriedad del vector de salida. En este trabajo se demostró que un polinomio de expansión de caos estima adecuadamente la propagación de la incerteza de las variables aleatorias. Los resultados mostraron que el parámetro material no solo afecta los coeficientes de variación del desplazamiento, sino también dicta el tipo y propagación de las colas de la función de densidad de probabilidad para la respuesta estructural. The uncertainty propagation in mechanical systems through model calculations was analyzed in this article by stochastic polynomial series of standardized random variables called Polynomial Chaos Expansion. This paper aimed to simulate the propagation of uncertainty in more complex mechanical models such viscoelastic structures which involves time dependent parameters characterization of materials, interconversion of mathematical functions through Laplace transform, and resolution of the constitutive equation through convolution integrals. The application of multi-dimensional Hermite polynomials series allowed the prediction of the randomness of the output vector. In this work it was demonstrated that a polynomial chaos expansion accurately estimated the spread of uncertainty of the random variables. The results showed that the material parameters not only affects the coefficient of variation of the displacements, but also dictates the type and spread of the tails of the probability density function for the structural output.
- Published
- 2016
41. Estado, religião e educação do cidadão
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Daner Hornich, Francisco Evangelista, and Antonio Carlos Miranda
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LC8-6691 ,LA5-2396 ,Estado Moderno ,laicidade ,religião ,History of education ,Special aspects of education ,Education - Abstract
Este artigo objetiva apontar os entraves e os conflitos entre Estado e religião e as perspectivas atuais sobre os desdobramentos dessa relação com a educação do cidadão. Faz uma reflexão e análise da fundação do Estado Moderno, e sua influência na formação das sociedades modernas e contemporâneas, bem como evidencia os impactos dos pressupostos da separação entre religião e Estado para considerar que a educação do cidadão passa pelo esclarecimento, e que esse esclarecimento democrático e republicano dos cidadãos passa pelas “[...] regras de uma educação pública” (Diderot, 2000, p. 268), pois o Estado deve ser o responsável pela educação, em diálogo constante com os diversos setores da sociedade, de tal forma que ‘o objeto do ensino e a extensão das lições devem proporcionar-se à pluralidade’. A ideia central é a de que pode existir um espaço para as questões religiosas dentro do Estado laico, mas elas devem ser orientadas pela razão que esclarece o cidadão e seja expressão da subjetividade e da liberdade humana. Nas relações entre o Estado, a religião e a educação do cidadão, cabe refletir sobre a desigualdade social e o impacto da religião na manutenção ou transformação de estruturas sociais injustas.
- Published
- 2016
42. Three-dimensional cohesive crack model prediction of the flexural capacity of concrete slabs on soil
- Author
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Cristian Gaedicke, Jeffery R. Roesler, and Francisco Evangelista
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Materials science ,business.industry ,Mechanical Engineering ,Fracture mechanics ,Structural engineering ,Crack growth resistance curve ,Finite element method ,Crack closure ,Flexural strength ,Mechanics of Materials ,Fracture (geology) ,Slab ,General Materials Science ,Geotechnical engineering ,business ,Stress concentration - Abstract
A three-dimensional approach to discretely account for crack initiation, crack growth, and determination of the flexural load capacity of concrete slabs on an elastic foundation under mode I loading is proposed. The finite element model incorporated cohesive crack elements along a pre-defined crack path in the concrete slab. A bilinear softening model was used to describe the stress-crack opening relationship for plain concrete and was defined solely on measured strength and fracture properties. The proposed method predicted the slab’s flexural load capacity as compared to the large-scale experimental concrete slab results for several geometries and notch configurations. The model also provided insight into stress concentration areas and crack propagation positions at different load levels.
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- 2012
- Full Text
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43. Prediction of Potential Cracking Failure Modes in Three-Dimensional Airfield Rigid Pavements with Existing Cracks and Flaws
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Jeffery R. Roesler, C. Armando Duarte, and Francisco Evangelista
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Materials science ,business.industry ,Mechanical Engineering ,Fracture mechanics ,Structural engineering ,Finite element method ,Crack closure ,Cracking ,Fracture (geology) ,Slab ,business ,Stress intensity factor ,Civil and Structural Engineering ,Stress concentration - Abstract
This paper predicts the potential for crack propagation in concrete pavements under aircraft loading given a starter fatigue crack at the bottom of the concrete slab or a surface-initiated shrinkage crack on top of the slab. The generalized finite element method was used to evaluate the stress intensity factors for quarter elliptical cracks placed at the critical top and bottom tensile stress locations. The pavement was loaded with a single triple-dualtandem (TDT) gear and two TDTs accounting for the entire belly gears. When the pavement was loaded with the two TDT gear configuration, the analyses showed significantly higher KI (shear mode) values for surface-initiated cracks than for bottom-initiated cracks for the same crack size. Therefore, concrete slabs with preexisting surface cracks are more likely to exhibit top-down crack growth despite being designed for bottom-up fatigue cracking under certain loading conditions. The theoretical framework allows for improved assessment of the fracture susceptibility of concrete slabs under aircraft loading, specifically the potential for top-down over bottom-up cracking.
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- 2012
- Full Text
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44. Dynamic Viscoelastic Analysis of Asphalt Pavements using a Finite Element Formulation
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Jorge Barbosa Soares, Áurea Silva de Holanda, Pedro Custodio De Araujo, Evandro Parente, and Francisco Evangelista
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Engineering ,Dynamic loading ,Deflection (engineering) ,business.industry ,Asphalt ,Dynamic modulus ,Shear stress ,Structural engineering ,business ,Dynamic load testing ,Viscoelasticity ,Finite element method ,Civil and Structural Engineering - Abstract
This paper studies the effect of time and load rate on the structural response of asphalt pavements when the surface layer is a linear viscoelastic material. A finite element incremental algorithm for dynamic analysis of viscoelastic solids is presented, where the stresses are computed using a hereditary integral in which the relaxation modulus is described by a Prony-Dirichlet series. The stresses are integrated in a semi-analytical form, whereas the dynamic equilibrium equations are integrated by the Trapezoidal Rule. Different pulse loads are considered and the viscoelastic responses of different asphalt layer thicknesses are compared. Several performance indicators typically utilized in pavement design are studied, particularly those at the surface layer, i.e., tensile stress and strain, shear strain, and surface deflection.
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- 2010
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45. Numerical Simulations of Fracture Resistance of Functionally Graded Concrete Materials
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Glaucio H. Paulino, Francisco Evangelista, and Jeffery R. Roesler
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Materials science ,Computer simulation ,business.industry ,Mechanical Engineering ,Fracture mechanics ,Fiber-reinforced concrete ,Structural engineering ,Residual ,Strength of materials ,Finite element method ,law.invention ,Cohesive zone model ,law ,business ,Material properties ,Civil and Structural Engineering - Abstract
The concept of grading material composition in a predetermined direction to target multiple objectives and functionality is applicable to the layering and positioning of different materials at specified depths. From a fracture mechanics perspective, this study explores the advantages of using functionally graded concrete materials (FGCMs), that is, plain concrete and fiber-reinforced concrete (FRC), in two distinct layers. The fracture energy ( G) and residual load capacity ( Ps) of two-layered concrete beams are investigated by means of numerical simulations with a cohesive zone model (CZM) implemented in a finite element framework. The required fracture parameters for defining the CZM are obtained from individual fracture tests of the plain concrete and FRC materials. The numerical simulations analyzed the effects of FRC thickness and position (whether at the top or bottom of the beam) on the fracture resistance of the two-layered concrete beam. A cost–benefit analysis showed that the FRC placed in the bottom lift is more fracture efficient (higher G- and Pδ-values at lower cost) than when it is placed in the top lift. There is also an optimal FRC thickness in which the benefit in fracture resistance is reduced as the FRC layer is increased. The application of a CZM to predict the fracture behavior of an FGCM beam has demonstrated its potential for also quantifying the effects of FGCMs on the fracture resistance of concrete pavements.
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- 2009
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46. Implementação do método dos elementos finitos generalizados com enriquecimento de interface
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Francisco Evangelista Junior, Gelson de Sousa Alves, and José Fabiano Araújo Moreira
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- 2016
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47. Model for Predicting Damage Evolution in Heterogeneous Viscoelastic Asphaltic Mixtures
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Jorge Barbosa Soares, Francisco Evangelista, David H. Allen, and Flavio V. Souza
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Cracking ,Cohesive zone model ,Materials science ,Mathematical model ,Asphalt ,Mechanical Engineering ,Geotechnical engineering ,Ductility ,Viscoelasticity ,Civil and Structural Engineering - Abstract
Cracking in the asphaltic layer of pavements has been shown to be a major source of distress in roadways. Previous studies in asphaltic mixture cracking typically have not considered the material heterogeneity. The sequel of a study in which the binder and the aggregates were treated as distinct materials is presented. Besides consideration of the viscoelastic behavior of the bulk asphalt binder, a micromechanical viscoelastic cohesive zone model introducing ductility at the crack tip has been considered. The simulations performed are verified and calibrated from simple and conventional laboratory tests. The study investigates crack evolution under monotonic loading, even though the method outlined can be further developed for the investigation of asphalt mixture fatigue.
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- 2004
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48. Reflexões sobre ser jovem na Educação de Jovens e Adultos no Brasil
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Adriana Alves Fernandes Costa and Francisco Evangelista
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060106 history of social sciences ,05 social sciences ,050301 education ,0601 history and archaeology ,06 humanities and the arts ,0503 education ,General Economics, Econometrics and Finance - Abstract
Sustentado em pesquisa documental e bibliográfica, o artigo aborda o direito de ser/aprender dos jovens que estão na Educação de Jovens e Adultos. Para isso, concebe a referida modalidade educativa como um lugar constituído de direitos dos sujeitos plurais que a compõe. Acenamos para a compreensão da cultura produzida por tais educandos, uma vez que as suas possíveis formas de ser e estar no mundo apontam configurações de potencialização de compreensão de delineamentos da EJA como espaço de produção de conhecimentos da pluralidade juvenil que converge com os saberes/conhecimentos de outras pessoas que estão em outra fase da vida (adultos e idosos). Assim, o texto indica a necessidade de considerar as singularidades imersas nas multiplicidades presentes nos distintos espaços educativos em que os jovens vivem, produzindo juventudes ainda pouco enxergadas pelos espaços educativos, essencialmente a escola. O texto ainda procura refletir qual o sentido da Educação de Jovens e Adultos no fazer do educador para a vida do educando.
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- 2018
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49. Uma estratégia global local para materiais compósitos utilizando o método dos elementos finitos generalizados
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Gelson de Sousa Alves and Francisco Evangelista Junior
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- 2015
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50. Geração de mapas de danos de fachadas a partir de processamento digital de imagens
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Antônio Alberto Nepomuceno, Carlos Mariano Melo Júnior, Gelson Sousa, Lenildo Santos da Silva, Francisco Evangelista, and Evangelos Dimitrios Christakou
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business.product_category ,business.industry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Digital photography ,Image processing ,Context (language use) ,Set (abstract data type) ,Geography ,Digital image processing ,Computer vision ,State (computer science) ,Artificial intelligence ,MATLAB ,business ,computer ,computer.programming_language ,Digital camera - Abstract
Dama ge maps are graphical representations that aim to identify and classify pathological manifestations in building facades in order to classify the operational and structural changes of the system condition. Currently, digital photography images are not limited to only register the state of the buildings since the high quality digital cameras and the existence of numerical tools enable the development of new methods of image processing. The digital image processing is the set of techniques for manipulating images, aiming to facilitate the extraction of information. Given the context, this paper aims to map and quantify stains and change of patterns on facades through digital image processing in a numerical tool implemented in MATLAB. The data presented are based on partial results that acquired images of the facades of the Central Library at University of Brasilia using a digital camera of 20.1 megapixels coupled to unmanned aerial vehicle (UAV). After the image acquisition, those were processed to generate orthoimages. The mapping of stains in MATLAB was performed to detect contour, color standards and minimum value desired area. Defects maps of the facades were also created with the quantitative
- Published
- 2014
- Full Text
- View/download PDF
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