Modelagem fuzzy para dinamica de transferencia de soropositivos para HIV em doença plenamente manifesta

Orientadores: Fernando Gomide, Laercio Carvalho de Barros, Rodney Carlos BassaneziTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de ComputaçãoDoutorad

Methodology to determine the evolution of asymptomatic HIV population using fuzzy set theory

The aim of this paper is to o study the evolution of positive HIV population for manifestation of AIDS, the Acquired Immunodeficiency Syndrome. For this purpose, we suggest a methodology to combine a macroscopic HIV positive population model with an individual microscopic model. The first describes the evolution of the population whereas the second the evolution of HIV in each individual of the population. This methodology is suggested by the way that experts use to conduct public policies, namely, to act at the individual level to observe and verify the manifest population. The population model we address is a differential equation system whose transference rate from asymptomatic to symptomatic population is found through a fuzzy rule-based system. The transference rate depends on the CD4+ level, the main T lymphocyte attacked by the HIV retrovirus when it reaches the bloodstream. The microscopic model for a characteristic individual in a population is used to obtain the CD4+ level at each time instant. From the CD4+ level, its fuzzy initial value, and the macroscopic population model, we compute the fuzzy values of the proportion of asymptomatic population at each time instant t using the extension principle. Next, centroid defuzzification is used to obtain a solution that represents the number of infected individuals. This approach provides a method to find a solution of a non-autonomous differential equation from an autonomous equation, a fuzzy initial value, the extension principle, and center of gravity defuzzification. Simulation experiments show that the solution given by the method suggested in this paper fits well to AIDS population data reported in the literature.The aim of this paper is to o study the evolution of positive HIV population for manifestation of AIDS, the Acquired Immunodeficiency Syndrome. For this purpose, we suggest a methodology to combine a macroscopic HIV positive population model with an indiv1313958CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOSEM INFORMAÇÃO304299/2003-

THE USE OF FUZZY RULE-BASED SYSTEMS IN DETERMINING HORIZONTAL PCO PARAMETERS OF GNSS ANTENNAS

Knowledge concerning Phase Center Offset (PCO) is an important aspect in the calibration of GNSS antennas and has a direct influence on the quality of high precision positioning. Studies show that there is a correlation between meteorological variables when determining the north (N), east (E) and vertical Up (H) components of PCO. This article presents results for the application of Fuzzy Rule-Based Systems (FRBS) for determining the position of these components. The function Adaptive Neuro-Fuzzy Inference Systems (ANFIS) was used to generate FRBS, with the PCO components as output variables. As input data, the environmental variables such as temperature, relative humidity and precipitation were used; along with variables obtained from the antenna calibration process such as Positional Dilution of Precision and the multipath effect. An FRBS was constructed for each planimetric N and E components from the carriers L1 and L2, using a training data set by means of ANFIS. Once the FRBS were defined, the verification data set was applied, the components obtained by the FRBS and Antenna Calibration Base at the Federal University of Paraná were compared. For planimetric components, the difference was less than 1.00 mm, which shows the applicability of the method for horizontal components

Manipulação e visualização de superfícies quádricas por meio de modelos impressos em 3D e modelos digitais

Neste artigo, apresentam-se resultados de uma pesquisa aplicada cujos dados empíricos foram obtidos de uma experiência pedagógica usando tecnologias digitais com 17 estudantes do Ensino Superior. O objetivo é compreender as possibilidades que a atividade experimental, desenvolvida com a utilização de modelos de superfícies quádricas produzidos em impressora 3D, trazem ao processo de ensinar e aprender Geometria Analítica. Os dados da pesquisa advieram de entrevistas concedidas pelos participantes da experiência, além de consulta aos arquivos e documentos da proposta. Na atividade didática, os estudantes se envolveram na manipulação, visualização e interpretação sobre formatos, medidas, posições e propriedades das superfícies. Os resultados permitiram a elaboração de uma proposta baseada em experimentações em um applet no GeoGebra, que possibilita integrar as explorações em modelos digitais de superfícies quádricas ao trabalho com modelos impressos em 3D

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Estamos interessados na equação integro-diferencial: x(t) = -2α[1 + x(t)] ∫-1/2-1 x(t + θ)dθ)dθ, α > 0. (E) Nosso objetivo é estudar as soluções periódicas de (E), que estão associadas aos pontos fixos de uma aplicação de retorno A sobre um conjunto fechado convexo do espaço de fase. Nós usamos um Teorema de R. Nussbaum para obter a existência de pontos fixos não triviais de A, quando α varia ao longo de uma sequência.We are concerned with the integro-differential equation: x(t) = -2α[1 + x(t)] ∫-1/2-1 x(t + θ)dθ)dθ, α > 0. (E) Our aim is to study the periodic solutions of (E), which are associated to fixed points of a return map A on a closed convex set of phase space. We use a fixed point theorem due to R. Nussbaum to accomplish the existence of nontrivial fixed points of A, when α varies along a sequence

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Estamos interessados na equação integro-diferencial: x(t) = -2α[1 + x(t)] ∫-1/2-1 x(t + θ)dθ)dθ, α > 0. (E) Nosso objetivo é estudar as soluções periódicas de (E), que estão associadas aos pontos fixos de uma aplicação de retorno A sobre um conjunto fechado convexo do espaço de fase. Nós usamos um Teorema de R. Nussbaum para obter a existência de pontos fixos não triviais de A, quando α varia ao longo de uma sequência.We are concerned with the integro-differential equation: x(t) = -2α[1 + x(t)] ∫-1/2-1 x(t + θ)dθ)dθ, α > 0. (E) Our aim is to study the periodic solutions of (E), which are associated to fixed points of a return map A on a closed convex set of phase space. We use a fixed point theorem due to R. Nussbaum to accomplish the existence of nontrivial fixed points of A, when α varies along a sequence

Biological models via interval type-2 fuzzy sets

This book offers a gentle introduction to type-2 fuzzy sets and, in particular, interval type-2 fuzzy sets and their application in biological modeling. Interval type-2 fuzzy modeling is a comparatively recent direction of research in fuzzy modeling. As the modeling of biological problems is inherently uncertain, the use of fuzzy sets in this field is a natural choice. The coverage begins with a succinct review of type-1 fuzzy basic theory, before providing a comprehensive and didactic explanation of type-2 fuzzy set components. In turn, Fuzzy Rule-Based Systems, or FRBS, are shown for both types, interval type-2 and type-1 fuzzy sets. Applications include the pharmacological models, prediction of prostate cancer stages, a model for HIV population transfer (asymptomatic to symptomatic), an epidemiological disease caused by HIV, some models in population growth, included the Malthus Model, and an epidemic model refers to COVID-19. The book is ideally suited to graduate students in mathematics and related fields, professionals, researchers, or the public interested in interval type-2 fuzzy modeling. Largely self-contained, it can also be used as a supplementary text in specialized graduate courses