Uncertainty and Fuzzy Sets: Classifying the Situation

The so called “Plural Uncertainty Model” is considered, in which statistical, maxmin, interval and Fuzzy model of uncertainty are embedded. For the last case external and internal contradictions of the theory are investigated and the modified definition of the Fuzzy Sets is proposed to overcome the troubles of the classical variant of Fuzzy Subsets by L. Zadeh. The general variants of logit- and probit- regression are the model of the modified Fuzzy Sets. It is possible to say about observations within the modification of the theory. The conception of the “situation” is proposed within modified Fuzzy Theory and the classifying problem is considered. The algorithm of the classification for the situation is proposed being the analogue of the statistical MLM(maximum likelihood method). The example related possible observing the distribution from the collection of distribution is considered.

Fuzzy sets: Abstraction Axiom, Statistical Interpretation, Observations of Fuzzy Sets

The issues relating fuzzy sets definition are under consideration including the analogue for separation axiom, statistical interpretation and membership function representation by the conditional Probabilities.

Visión y análisis de las propuestas de reforma al Sistema General de Seguridad Social en Salud en Colombia, vigencia 2012-2013

Con la Constitución Política de 1991, se inicia una nueva estructura funcional en el país a partir de los preceptos consagrados en la carta magna como un estado social de derecho, situación que no fue ajena al sector salud en el cual se estableció la seguridad social como un servicio público basado en los principios fundamentales de universalidad, solidaridad y eficiencia, enunciados que fueron plasmados entre otros en la Ley 100 de 1993, la cual incorporó estos elementos que resultaban innovadores en el contexto. Hoy después de 18 años de promulgada la Ley, se ha generado un modelo estructural que ha permitido mejorar los resultados en esta área, que si bien posee falencias en algunos de sus componentes (Acceso, Flujo de Recursos, Salud Pública), las mismas pueden ser superadas, con una reforma estructural al sistema que elimine los intereses particulares de los diferentes actores al momento de su elaboración y promulgación. Uno de los avances significativos en la reforma al sistema es la promulgación de la salud como derecho fundamental, inherente al ser humano, otorgando el carácter de inalienable, imprescriptible y sagrado, dejando en segundo plano su condición prestacional establecida. El derecho a la salud tendrá como eje principal la salud pública armonizada con la promoción y prevención, diagnóstico y tratamiento integral de la enfermedad, las cuales deben ser articuladas con las políticas sociales, ambientales, culturales y económicas que permitan incidir en los determinantes sociales de la salud para mejorar la calidad de vida de la población. La reforma a la salud en el eje de la financiación como se encuentra propuesta, no generará cambios sustanciales toda vez que se avanza hacia un sistema en que el estado será el principal actor con las funciones afiliación, recaudo, pago, giro o transferencia de los recursos, responsable de la información. Sin embargo la administración del riesgo en salud seguirá delegada, función que es determinante para la administración de los recursos del sistema, en resumen se demuestra el interés del estado en retomar la gobernanza y su empoderamiento como administrador de lo público, sin que esto responda a las necesidades de cambio en el sistema de salud.

Estimativa da área impermeável dentro da bacia hidrográfica do Arroio Diluvio (porto Alegre/RS) através de técnicas de sensoriamento remoto e geoprocessamento

Neste trabalho foram realizadas classificações utilizando-se as bandas 1 a 5 e 7 dos sensores Landsat 5 TM (1987) e Landsat 7 ETM+ (2000). A caracterização espectral dos materiais foi realizada em laboratório utilizando um espectrorradiômetro, e através das bandas 1 a 5 e 7 dos sensores Landsat 5 TM (1987) e Landsat 7 ETM+ (2000). A transformação dos dados multiespectrais de imagens de sensoriamento remoto é uma maneira de reduzir o volume de dados através da identificação de classes de interesse numa imagem digital. No intuito de verificar condições de melhoramento na classificação de alvos urbanos em imagens digitais, identificados por procedimentos já conhecidos, como a classificação pela Máxima Verossimilhança, escolheu-se um classificador baseado na lógica fuzzy. O classificador utilizado foi o Fuzzy Set Membership classification - Fuzclass, que faz parte de um conjunto de classificadores não-rígidos disponíveis no programa Idrisi 32. Uma vez que informações sobre o desempenho de produtos deste classificador em áreas urbanas são escassas, foram conduzidos ensaios de comparação de resultados obtidos por este classificador com a verdade terrestre, representada por uma imagem de alta resolução espacial do satélite QuickBird. As áreas teste selecionadas desta imagem atendem ao critério de inalterância das condições de ocupação para o intervalo temporal considerado A comparação feita, permite concluir que o classificador apresenta limitações na classificação de áreas urbanas devido ao comportamento espectral semelhante dos materiais que fazem parte dessa cobertura. A utilização de uma classe única para identificar áreas impermeáveis foi a solução adotada para contornar este óbice. O emprego de áreas teste possibilitou acertar a escolha do grau de possibilidade de presença da classe no pixel (PPCP). Uma comparação entre os resultados apresentados na classificação de áreas impermeáveis, com base nos classificadores Máxima Verossimilhança e Fuzclass, demonstrou um desempenho melhor do classificador fuzzy, em função do nível de PPCP ajustado durante a análise comparativa Landsat e Quickbird nas áreas teste. Um procedimento alternativo de estimativa de áreas impermeáveis em bacias urbanas é apresentado no final.

Optimization procedures in the design of continuous induction hardening and tempering installations for magnetic steel bars

An inverse problem concerning the industrial process of steel bars hardening and tempering is considered. The associated optimization problem is formulated in terms of membership functions and, for the sake of comparison, also in terms of quadratic residuals; both geometric and electromagnetic design variables have been considered. The numerical solution is achieved by coupling a finite difference procedure for the calculation of the electromagnetic and thermal fields to a deterministic strategy of minimization based on modified Flctcher and Reeves method. © 1998 IEEE.

Sintetizador analógico de sinais ortogonais: projeto e construção usando tecnologia CMOS

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Neurofuzzy network model construction using Bézier-Bernstein polynomial functions

Neurofuzzy modelling systems combine fuzzy logic with quantitative artificial neural networks via a concept of fuzzification by using a fuzzy membership function usually based on B-splines and algebraic operators for inference, etc. The paper introduces a neurofuzzy model construction algorithm using Bezier-Bernstein polynomial functions as basis functions. The new network maintains most of the properties of the B-spline expansion based neurofuzzy system, such as the non-negativity of the basis functions, and unity of support but with the additional advantages of structural parsimony and Delaunay input space partitioning, avoiding the inherent computational problems of lattice networks. This new modelling network is based on the idea that an input vector can be mapped into barycentric co-ordinates with respect to a set of predetermined knots as vertices of a polygon (a set of tiled Delaunay triangles) over the input space. The network is expressed as the Bezier-Bernstein polynomial function of barycentric co-ordinates of the input vector. An inverse de Casteljau procedure using backpropagation is developed to obtain the input vector's barycentric co-ordinates that form the basis functions. Extension of the Bezier-Bernstein neurofuzzy algorithm to n-dimensional inputs is discussed followed by numerical examples to demonstrate the effectiveness of this new data based modelling approach.

Leontief Model Analysis with Fuzzy Parameters by Basic Matrixes Method

The basic matrixes method is suggested for the Leontief model analysis (LM) with some of its components indistinctly given. LM can be construed as a forecast task of product’s expenses-output on the basis of the known statistic information at indistinctly given several elements’ meanings of technological matrix, restriction vector and variables’ limits. Elements of technological matrix, right parts of restriction vector LM can occur as functions of some arguments. In this case the task’s dynamic analog occurs. LM essential complication lies in inclusion of variables restriction and criterion function in it.

Use of correlated potential harmonic basis functions for the description of the (4)He trimer and small clusters

A correlated many-body basis function is used to describe the (4)He trimer and small helium clusters ((4)HeN) with N = 4-9. A realistic helium dimer potential is adopted. The ground state results of the (4)He dimer and trimer are in close agreement with earlier findings. But no evidence is found for the existence of Efimov state in the trimer for the actual (4)He-(4)He interaction. However, decreasing the potential strength we calculate several excited states of the trimer which exhibit Efimov character. We also solve for excited state energies of these clusters which are in good agreement with Monte Carlo hyperspherical description. (C) 2011 American Institute of Physics. [doi:10.1063/1.3583365]

Fuzzy pole placement based on piecewise Lyapunov functions

This paper presents a controller design method for fuzzy dynamic systems based on piecewise Lyapunov functions with constraints on the closed-loop pole location. The main idea is to use switched controllers to locate the poles of the system to obtain a satisfactory transient response. It is shown that the global fuzzy system satisfies the requirements for the design and that the control law can be obtained by solving a set of linear matrix inequalities, which can be efficiently solved with commercially available softwares. An example is given to illustrate the application of the proposed method. Copyright (C) 2009 John Wiley & Sons, Ltd.

A method for the design of MRI radiofrequency coils based on triangular and pulse basis functions

This paper presents a numerical technique for the design of an RF coil for asymmetric magnetic resonance imaging (MRI) systems. The formulation is based on an inverse approach where the cylindrical surface currents are expressed in terms of a combination of sub-domain basis functions: triangular and pulse functions. With the homogeneous transverse magnetic field specified in a spherical region, a functional method is applied to obtain the unknown current coefficients. The current distribution is then transformed to a conductor pattern by use of a stream function technique. Preliminary MR images acquired using a prototype RF coil are presented and validate the design method. (C) 2002 Elsevier Science B.V. All rights reserved.

A two-dimensional fuzzy random model of soil pore structure

A new conceptual model for soil pore-solid structure is formalized. Soil pore-solid structure is proposed to comprise spatially abutting elements each with a value which is its membership to the fuzzy set ''pore,'' termed porosity. These values have a range between zero (all solid) and unity (all pore). Images are used to represent structures in which the elements are pixels and the value of each is a porosity. Two-dimensional random fields are generated by allocating each pixel a porosity by independently sampling a statistical distribution. These random fields are reorganized into other pore-solid structural types by selecting parent points which have a specified local region of influence. Pixels of larger or smaller porosity are aggregated about the parent points and within the region of interest by controlled swapping of pixels in the image. This creates local regions of homogeneity within the random field. This is similar to the process known as simulated annealing. The resulting structures are characterized using one-and two-dimensional variograms and functions describing their connectivity. A variety of examples of structures created by the model is presented and compared. Extension to three dimensions presents no theoretical difficulties and is currently under development.

F-LQE: a Fuzzy Link Quality Estimator for wireless sensor networks

Radio Link Quality Estimation (LQE) is a fundamental building block for Wireless Sensor Networks, namely for a reliable deployment, resource management and routing. Existing LQEs (e.g. PRR, ETX, Fourbit, and LQI ) are based on a single link property, thus leading to inaccurate estimation. In this paper, we propose F-LQE, that estimates link quality on the basis of four link quality properties: packet delivery, asymmetry, stability, and channel quality. Each of these properties is defined in linguistic terms, the natural language of Fuzzy Logic. The overall quality of the link is specified as a fuzzy rule whose evaluation returns the membership of the link in the fuzzy subset of good links. Values of the membership function are smoothed using EWMA filter to improve stability. An extensive experimental analysis shows that F-LQE outperforms existing estimators.

Node adaptation for global collocation with radial basis functions using direct multisearch for multiobjective optimization

Meshless methods are used for their capability of producing excellent solutions without requiring a mesh, avoiding mesh related problems encountered in other numerical methods, such as finite elements. However, node placement is still an open question, specially in strong form collocation meshless methods. The number of used nodes can have a big influence on matrix size and therefore produce ill-conditioned matrices. In order to optimize node position and number, a direct multisearch technique for multiobjective optimization is used to optimize node distribution in the global collocation method using radial basis functions. The optimization method is applied to the bending of isotropic simply supported plates. Using as a starting condition a uniformly distributed grid, results show that the method is capable of reducing the number of nodes in the grid without compromising the accuracy of the solution. (C) 2013 Elsevier Ltd. All rights reserved.

Anatomically informed basis functions

Neuroimaging, functional image analysis, spatial model, cortical surface, spatially variable convolution