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Search Results: 1 - 10 of 19427 matches for " Claucio;Ferreira "
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The presence of Lutzomyia longipalpis in a focus of American visceral leishmaniasis where the only proven vector is Lutzomyia cruzi. Corumbá, Mato Grosso do Sul State
Santos, Soraya Oliveira dos;Arias, Jorge R.;Hoffmann, Marta de Paiva;Furlan, Mara Beatriz Grotta;Ferreira, Wilson Francisco;Pereira, Claucio;Ferreira, Lourival;
Revista da Sociedade Brasileira de Medicina Tropical , 2003, DOI: 10.1590/S0037-86822003000500017
Abstract: the present communication reports the presence of lutzomyia longipalpis in corumbá, mato grosso do sul, where the principal vector is lutzomyia cruzi.
Manufacturing Cells Formation Based on Graph Coloring  [PDF]
José Francisco Ferreira Ribeiro
Journal of Service Science and Management (JSSM) , 2010, DOI: 10.4236/jssm.2010.34056
Abstract: A method for cellular manufacturing design in Group Technology is presented in this paper. The proposed method computes the dissimilarities between parts and organizes the production system in part-families and group-machines. A graph corresponding to the production system is generated and a coloring algorithm is activated in order to obtain a number of cells equal to the desired number of cells. The corresponding program was written in Matlab language and runs on a microcomputer. The results obtained on several examples found in the literature are consistently equivalent to or even better than those hitherto proposed, in terms of inter-cell moves and dimensions of the cells.
Distance Learning and Administrators Training in Basic Education: The Importance, Principles and Meanings in Contemporaneity  [PDF]
Naura Syria Carapeto Ferreira
Open Journal of Social Sciences (JSS) , 2015, DOI: 10.4236/jss.2015.32003
Abstract:

This article addresses three fundamental elements in contemporaneity for Brazilians and worldwide people: The Distance Learning, the Administrators Training and the Basic Education. It is necessary to understand them within the relation that links them and demonstrates responsibility from the principles and meanings committed with citizen human formation of all the Brazilian and worldwide population. Therefore, I will point at re-signifying those elements in this relation, opening ways to purposeful ideas.

Classroom Analysis of a Packed Bed Reactor with and without the Use of Effectiveness Factor  [PDF]
Sebastiao R. Ferreira
Creative Education (CE) , 2016, DOI: 10.4236/ce.2016.715209
Abstract: Classroom analysis of a packed bed reactor with and without the use of effectiveness factor (η) is discussed in this article. The use of (η) in the calculation of an isothermal packed bed reactor with convection and first-order reaction rate is analyzed. An analytical model has been developed with and without (η). The model without (η) was presented in a 50-min lecture and later used in a 50-min computational laboratory session with various groups of two students to calculate the length and catalyst mass in a packed bed reactor. In another class, the students calculated the model using (η). Four or five class activities were tested every month in pairs of students in the place of traditional exams. A questionnaire was prepared to verify the students’ level of difficulty in understanding two theoretical topics taught in the last two classes, difficulty in doing the requested calculations, as well as among calculations using the effectiveness factor and without it. We have included a question in the questionnaire on how the students felt about the elimination of one traditional monthly exam in Chemical Reactor Design. In the two semesters when the questionnaire was applied to the Chemical Reactor Design class, on average, 86% of the students preferred various class group activities as opposed to traditional exams, 80% of the students reported that they had little difficulty in understanding the two theoretical sections in the last two classes, 57% stated that they did not have any difficulty in doing the requested calculations and 51% reported that the calculation methods with the use of (η) and without its use were somewhat similar.
The Pattern of Prime Numbers  [PDF]
José William Porras Ferreira
Applied Mathematics (AM) , 2017, DOI: 10.4236/am.2017.82015
Abstract: The prime numbers P≥5 obey a pattern that can be described by two forms or geometric progressions \"\" or \"\" that facilitates obtaining them sequentially, being possible also to calculate the quantity of primes that are in the geometric progressions \"\" as it is described in this document.
Love as Attunement  [PDF]
Acylene Maria Cabral Ferreira
Open Journal of Philosophy (OJPP) , 2018, DOI: 10.4236/ojpp.2018.82008
Abstract: We aim to show, using Being and Time and Zollikon Seminars, that solicitude (Fürsorge) as the disclosedness of being-with is the condition of possibility for the existential-ontological constitution of the attunement of love. Centered on the text On the Essence of Truth, our purpose is to emphasize that freedom is also an attunement. Our hypothesis is that the copertinence of love (the fundamental disclosedness to the other) and of freedom (the letting-be of the other) consists in a modification of the existential of disposedness (Befindlichkeit) and expresses the unity and ontological circularity of being-in-the-world.
Utiliza??o do SF-6D na medi??o das preferências dos portugueses: sistema de valores e normas da popula??o dos 18 aos 64 anos
Ferreira,Lara; Ferreira,Pedro;
Revista Portuguesa de Saúde Pública , 2011,
Abstract: introduction: there has been an increasing interest in the study of the health state valuations across countries. evidence suggests that health state valuations may differ from country to country. in recent years there has been increasing interest in surveys conducted to obtain value sets for the most used preference-based instruments, such as the eq-5d, the hui and the sf-6d. a portuguese value set for the sf-6d was recently published. however this system weight had some inconsistencies in what concerned the weights of the six dimensions of the sf-6d. the correction of these inconsistencies would improve the value set. this study seeks to present the portuguese system weight for the sf-6d without inconsistencies. it also aims at providing portuguese norms for individuals aged 18-64 for the sf-6d. methods: inconsistencies were found in some levels of the dimensions of the sf-6d. these levels were aggregated and parsimonious models were estimated through generalized estimating equations. the data used to obtain the portuguese norms for individuals aged 18-64 came from a random sample of the portuguese population aged 18-64 (n=2,459). the sf-36v2 was applied to this sample and results from the best parsimonious model were used to obtain the portuguese norms for individuals aged 18-64. results: aggregating levels of each dimension whenever inconsistencies occurred enabled to obtain a portuguese system weight for the sf-6d. however there are still some problems of under prediction in some states assigned to poor health. the mean utility value obtained for the portuguese working age population was 0.81 (associated with a standard deviation of 0.12). portuguese norms for the sf-6d for individuals aged 18-64 were computed by gender, age, marital status and educational level. lower levels of utilities were observed in women, the elderly, individuals with low educational level, widowed and individuals living in rural areas. conclusion: this research demonstrates that it is p
Extremes of scale mixtures of multivariate time series
Helena Ferreira,Marta Ferreira
Mathematics , 2013,
Abstract: Factor models have large potencial in the modeling of several natural and human phenomena. In this paper we consider a multivariate time series $\mb{Y}_n$, ${n\geq 1}$, rescaled through random factors $\mb{T}_n$, ${n\geq 1}$, extending some scale mixture models in the literature. We analyze its extremal behavior by deriving the maximum domain of attraction and the multivariate extremal index, which leads to new ways to construct multivariate extreme value distributions. The computation of the multivariate extremal index and the characterization of the tail dependence show the interesting property of these models that however much it is the dependence within and between factors $\mb{T}_n$, ${n\geq 1}$, the extremal index of the model is unit whenever $\mb{Y}_n$, ${n\geq 1}$, presents cross-sectional and sequencial tail independence. We illustrate with examples of thinned multivariate time series and multivariate autoregressive processes with random coefficients. An application of these latter to financial data is presented at the end.
Extremes of multivariate ARMAX processes
Marta Ferreira,Helena Ferreira
Statistics , 2012,
Abstract: We define a new multivariate time series model by generalizing the ARMAX process in a multivariate way. We give conditions on stationarity and analyze local dependence and domains of attraction. As a consequence of the obtained result, we derive a new method of construction of multivariate extreme value copulas. We characterize the extremal dependence by computing the multivariate extremal index and bivariate upper tail dependence coefficients. An estimation procedure for the multivariate extremal index shall be presented. We also address the marginal estimation and propose a new estimator for the ARMAX autoregressive parameter.
Extremal dependence: some contributions
Helena Ferreira,Marta Ferreira
Statistics , 2011,
Abstract: Due to globalization and relaxed market regulation, we have assisted to an increasing of extremal dependence in international markets. As a consequence, several measures of tail dependence have been stated in literature in recent years, based on multivariate extreme-value theory. In this paper we present a tail dependence function and an extremal coefficient of dependence between two random vectors that extend existing ones. We shall see that in weakening the usual required dependence allows to assess the amount of dependence in $d$-variate random vectors based on bidimensional techniques. Very simple estimators will be stated and can be applied to the well-known \emph{stable tail dependence function}. Asymptotic normality and strong consistency will be derived too. An application to financial markets will be presented at the end.
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