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Artigo de evento A different statistical approach aiming at EEG parameter investigation for brain machine interface use(2014-03-06) DE CASTRO, M. C. F.; Fábio GerabA lot of effort has been made to investigate EEG features that could better represent signal characteristics. The results are usually based on the best mean recognition rates and statistical analysis is done only when different methods are compared. In this work, we propose a new approach that applies multiple rate intercomparisons based on large samples aiming at detecting differences among treatments in order to recognize their importance for the classification rates. Ten frequency band compositions expressed by power spectral density averages were extracted from 8 EEG channels during 4 motor imageries, and spatial feature selections were also considered during the recognition process. Classification rate in large samples can be represented by a normal distribution and, for multiple rate inter-comparisons, the level of significance was corrected based on the Bonferroni Method. The variables were considered to be independents and the test was performed as non paired samples in a very conservative approach. The results showed that there are significant differences among cases of spatial feature selection and thus the considered electrodes are important parameters. On the other hand, considering or not the Delta and Theta bands along with different arrangements for Gamma band resulted in no significant difference. Copyright © 2014 SCITEPRESS - Science and Technology Publications. All rights reserved.Artigo Stopping probabilities for patterns in markov chains(2014-03-05) GAVA, R. J.; SALOTTI, D.Consider a sequence of Markov-dependent trials where each trial produces a letter of a finite alphabet. Given a collection of patterns, we look at this sequence until one of these patterns appears as a run. We show how the method of gambling teams can be employed to compute the probability that a given pattern is the first pattern to occur. © Applied Probability Trust 2014.Artigo Sustainability reports in Brazil through the lens of signaling, legitimacy and stakeholder theories(2017-01-05) Ching, H. Y.; Fábio Gerab© 2017 Emerald Publishing Limited.Purpose - The purpose of this paper is to extend the applicability of stakeholder, legitimacy and signaling theories by examining to what extent proactive corporate social responsibility disclosures are interrelated to attempt to gain and maintain legitimacy, to gain support of the stakeholders and to reduce information asymmetry. Design/methodology/approach - To test the theoretical arguments, a longitudinal approach over a five-year period of 145 companies' sustainability reports and statistical analysis was applied to investigate the evolution of their quality. Findings - The results show a significant increase in the quality of sustainability reporting, and the experience gained while writing these reports can contribute to this. Based on signaling and legitimacy theories, this paper suggests that improvement in sustainability reporting quality acts as an important signal to gain legitimacy in case of information asymmetry during the legitimacy process. Th disclosure for economic and social dimensions is better than that of the environmental dimension, and the improvement in quality over time is the because of synergies and interlinkages more between these two dimensions of sustainability, and to a lesser extent because of the environmental dimension. Practical implications - Firms should view investing in sustainability reporting disclosure as a strategy for obtaining business legitimacy. Originality/value - The results of this paper are of interest for several reasons: extend and broaden the use of signaling in studying its use on sustainability reporting; the use of three theories is an appropriate framework for empirical analysis of sustainability reporting disclosure quality in Brazil; and add to the scarce evidence of sustainability reporting in Brazil.Artigo Characterization of heterogeneities in grain size by network analysis(2017-05-01) DUTRA, J. C.; DE OLIVEIRA, T. E.© 2017 Elsevier Inc.Heterogeneities in grain size are very common, mainly when phenomena such as abnormal grain growth is taking place. A new method to measure them is put forward. It is based on network analysis in which an adjacent matrix is built from a microstructure consisting of single-phase grains. In this approach, grains are nodes whereas their boundaries are ties. Both the degree centrality of nodes and the degree centrality of group of grains were calculated as well as their significance and deviations. Results have shown that the present method is capable to show significant differences in these properties, one order of magnitude, even if the microstructures are slightly heterogeneous. Methods involving statistical and non-linear regression analysis are also presented and compared with the new one and it is shown that these methods have more arbitrariness than the new one.Artigo de evento Good codes from metacyclic groups(2019) Samir Assuena; MILIES, C. P.© 2019 American Mathematical Society.In this paper, we consider semisimple group algebras Fq G of split metacyclic groups over finite fields. We construct left codes in Fq G in the case when the order G is pm ℓn, where p and ℓ are different primes such that gcd(q, p, ℓ) = 1.Artigo de evento Methods and concepts for elaborating a decision aided tool for optimizing healthcare medicines dispatching flows(2019-06-24) PINHEIRO, J. C.; DOSSOU, P.-E.; João Chang Junior© 2019 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)Globalization and new technologies are causes of the development of industry 4.0 concepts. Nowadays, Industry is becoming increasingly technological, machines are reaching spaces previously destined in factories to humans. Indeed, industry 4.0 concepts based on scientific, technological, and organizational concepts & tools (Internet of thing, RFID, Cobots, decision aided tools) and including sustainability could be used in different activity sectors. Healthcare sector is being transformed by new technologies and complex problems of this sector are solved by insisting on new technological parameters. FEI and Icam engineering schools are collaborating on healthcare logistics & transport area. The idea is to use the previous approach being elaborated for industrial companies to improve healthcare logistics and transport domain (Healthcare logistics 4.0). This paper presents concepts and tools (healthcare logistics 4.0) for solving real healthcare logistics problems. The approach elaborated is hybrid (combination of experimentation for acquiring real data and design for elaborating concepts and methods required for developing an adapted problem-solving tool). The decision aided tool is elaborated by using formalisms of artificial intelligence (such as expert systems, machine learning, multi-agent systems) in order to optimize medicine dispatching flows in a hospital. After describing healthcare logistics dispatching problems, a literature review will be presented for choosing concepts and formalisms that could be for developing the new decisional tool. Then, an example will be given for illustrating concepts elaborated.Artigo Good codes from metacyclic groups II(2022-02-01) Samir Assuena© 2022 World Scientific Publishing Company.In this paper, we consider semisimple group algebras qG of split metacyclic groups over finite fields. We construct left codes in qG in the case when the order G is pmâ.,"n, where p and â.,"are different primes such that gcd(q,p,â.,") = 1 extend the construction described in a previous paper, determine their dual codes and find some good codes.Artigo Education, school and school mathematics: meanings of the basic education mathematics teachers*(2021-01-05) GODOY, E. V.; Fábio Gerab; SANTOS, V. D. M.© 2021. All Rights Reserved.The mathematics teacher initial training has been the subject of discussion in the governmental spheres and in the Brazilian Societies of Mathematical Education and of Mathematics. As a consequence of this, we notice advances in some critical points, among which stands out - the excess of academic mathematics disarticulated from the school mathematics; and - the approximation of the mathematics education theoretical-methodological trends with the mathematics undergraduate courses curricular organization. However, there are still absent the conversations involving the different and varied dimensions that interfere in the teaching and learning process of school mathematics; and the different curriculum theories. As a result, the neutrality of mathematical knowledge and the excessive concern with the normative dimension of the curriculum continue being protagonists in the mathematics teacher initial training. In this sense, this article aimed to investigate aspects related to the perception and understanding of basic education mathematics teachers about the school subjects, the school, the school education and about being a math teacher. Methodologically, it is included in a quali-quantitative research approach, in which, in order to achieve the project's objectives, a field research, through a questionnaire available in the “Google docs”, was carried out with the public network mathematics teachers from Sao Paulo state. Theoretically, it was based on studies about curriculum theories. It was tangible that the collaborating teachers are still very attached to the normative dimension of the curriculum, always prioritizing what to teach, how to teach and how to evaluate, without worrying about other dimensions (cultural, social, political) that interfere in the curriculum organization.of the school mathematics.Artigo A divulgação de conhecimentos científicos no Brasil entre os séculos XVIII e XIX : comentários e reflexões(2019-07-07) TRENTIN, Paulo HenriqueEste texto comenta e apresenta reflexões em relação aos argumentos apresentados por autores, tradutores e outros responsáveis pela divulgação dos conhecimentos científicos no Brasil, do final do século XVIII ao início do século XIX. Selecionamos para a análise as seguintes obras: Elementos de Astronomia, 1813, Tratado Elementar de Mechanica, 1812, Tratado de Optica, 1813, Tratado Elementar de Physica tomo II, 181 e o Jornal O Patriota, 1813-1814. A análise identifica algumas expectativas manifestadas pelos autores, tradutores e editores dos textos selecionados, como motivações sociais, políticas ou econômicas. Especificamente, destaca-se a relevância de anseios, desejos e expectativas manifestações dos autores dos textos para além da influência do ambiente social, político e econômico ao qual pertenciam. O estudo nos permitiu considerar que não há resposta definitiva acerca das ambições ou expectativas motivaram a divulgar conhecimentos científicos. Porém, no que se refere à “utilidade” que atribuíam ao conhecimento divulgado, foi possível tecer algumas considerações que deverão contribuir para a historiografia acerca do tema.Artigo Transformações lineares planas: um estudo com base nos registros de representação semiótica e na utilização da geometria dinâmica(2009-06-05) KARRER, Monica; JAHN, A.P.Este artigo apresenta um estudo relativo ao ensino e à aprendizagem da noção de transformação linear. Baseados em considerações teóricas sobre registros de representação semiótica e aprendizagem em Matemática, foram realizadas análises de livros didáticos e de um questionário aplicado a oitenta e seis estudantes universitários da área computacional. Estes estudos apontaram deficiências com relação ao uso dos registros numérico-tabular e gráfico de uma transformação linear. Utilizando a metodologia de design experiment,foram elaboradas e aplicadas atividades envolvendo diversas representações de transformações planas, nos ambientes Cabri-Géomètre e papel&lápis. Os principais resultados deste experimento são aqui relatados, destacando-se o papel do softwareutilizadoArtigo Relação entre o desempenho em física e o desempenho em outras disciplinas da etapa inicial de um curso de engenharia(2014) GERAB, F.; VALERIO, A. D. A.Artigo Relationship between working capital management and profitability in brasilian listed companies(2011) Ching, H.Y.; NOVAZZI, A.; GERAB, F.;GERAB, FÁBIOArtigo Transição ensino médio - ensino de engenharia na perspectiva do professor de matemática(2018) GODOY, E. V.; GERAB, FábioArtigo Avaliação da Disciplina de Formação Didático Pedagógica em Saúde: a óptica do pós-graduando(2014) GERAB, I. F. S.; BATISTA, S. H. S. S.; SONZOGNO, M. C.; YAMASHIRO, C. G.; GERAB, F.;GERAB, FÁBIO; RUIZ-MORENO, L.Artigo Analysis of sustainability reports and quality of information disclosed of top brazilian companies(2013) CHING, Hong; GERAB, Fábio; TOSTE, Thiago HenriqueThe objective of this research is to examine the quality of information disclosed from a sample of Brazilian listed companies, using a multidimensional construct based on economic, environmental and social dimensions of sustainability. The research design combines both quantitative and qualitative methods. The qualitative approach is used in the content analysis procedure and the quantitative is employed for statistical analysis. The target population consists of top 36 sustainable companies (ISE) and 24 with corporate governance practices (NM) in 2011. We find that 37% of the companies achieved score above 0.5; 30% between 0.26 and 0.5 and 33% scored below 0.25, being score zero the worst and one the best score. The best company scored 0.896 and the worst of the 60 companies scored 0.0167. Overall our statistical results confirm that ISE companies tend to disclose more information and in a more adequate way than NM, and in general, the companies are reporting the content in all the three dimensions with same quality level. Furthermore, companies from Infrastructure sector present better quality content reported when compared to Service companies. We conclude that a good sustainability report is directly related to the good content in all the tree dimensions, regardless the economic sector and these reports still have a big room for improvement, which echoes within the literature analyzed. Companies need to disclose their information in a more integrated way, addressing sustainability issues under the scope of business strategy.Artigo Scoring Sustainability Reports using GRI indicators: A Study based on ISE and FTSE4Good Price Indexes(2014) CHING, Hong; GERAB, Fábio; TOSTE, T.Artigo Análise das interações curriculares em um curso de ciência da computação: buscando subsídios para aprimoramento curricular(2014) GERAB, Fábio; BUENO, I. A. M.; GERAB, I. F. da S.O processo de mudança curricular deve estar alicerçado em evidências institucionais de mudanças. Neste sentido, o presente trabalho objetiva caracterizar e discutir as interações curriculares em um curso de Ciência da Computação a partir do desempenho dos alunos egressos. Os dados de desempenho foram submetidos à Análise de Componentes Principais e à Análise por Agrupamento Hierárquico para identificar eventuais correlações entre: o rendimento nas distintas disciplinas, a influência da classificação no exame de ingresso e o tempo necessário para a conclusão do curso. Observou-se a associação de disciplinas em nove grupos, com destaque para o agrupamento rotulado de “Básicas”, que interfere na duração do curso. Notou-se que o desempenho no vestibular perde sua importância no decorrer do curso. Compreender estas relações pode contribuir para a melhoria do curso de Ciência da Computação e favorecer o bom aproveitamento do aluno.Artigo The quality of sustainability reports and corporate financial performance: evidence from Brazilian listed companies(2017) Ching, H.Y.; GERAB, F.; TOSTE, T.Artigo GROUP RINGS OVER FROBENIUS RINGS(2018) ASSUENA, S.