José Luis Verdegay Galdeano

El problema del arbol minimal para grafos difusos

ResumenBasándonos en algunas definiciones previas, se analizan el problema del árbol generador difuso. En primer lugar se trata su existencia y después se encuentra el árbol generador difuso de mínimo costo mediante una descomposición por α-cortes. El estudio se realiza para dos estructuras diferentes de costos.AbstractOn the basis of previous definitions, the problem of spanning a fuzzy tree is analyzed. First we treat its existence and then spanning fuzzy tree of minimum cost is found by means of a α-out decomposition. We have done this with two different assumptions about the costs structure.

Fault Diagnosis in a Steam Generator Applying Fuzzy Clustering Techniques

In this chapter the design of a fault diagnosis system using fuzzy clustering techniques for a BKZ-340-140 29M steam generator in a thermoelectric power station is presented. The application aims to study the advantages of these techniques in the development of a fault diagnosis method with the characteristic to be robust to external disturbances and sensitive to small magnitude faults. The wavelet transform (WT) is used for isolating noise present in measurements. The fault diagnosis system was designed for the water-steam circuit of the steam generator by its great incidence in the correct operation of the generation blocks. The obtained results indicate the feasibility of the proposal.

Solving Regression Analysis by Fuzzy Quadratic Programming

Regression analysis, which includes any techniques for modeling and analyzing several variables, is a statistical tool that focuses in finding a relationship between a dependent variable and one or more independent variables. When this relationship is found, some values of parameters are determined which help a function to best fit in a set of data observations. In regression analysis, it is also interesting to characterize the variation of the depend variable around the independent ones. A regression problem can be formulated as a mathematical programming problem, where the objective is to minimize the difference between the estimated values and the observed values. This proposal provides a fuzzy solution to the problem that involves all particular -punctual- solutions provided by other methods. To clarify the above developments, a numerical example about the price mechanism of prefabricated houses is analyzed.