Rodney R. Saldanha

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Paracoccidioides brasiliensis is a pathogenic fungus that undergoes a temperature-dependent cell morphology change from mycelium (22 degrees C) to yeast (36 degrees C). It is assumed that this morphological transition correlates with the infection of the human host. Our goal was to identify genes expressed in the mycelium (M) and yeast (Y) forms by EST(More)
This paper presents a new learning scheme for improving generalization of multilayer perceptrons. The algorithm uses a multi-objective optimization approach to balance between the error of the training data and the norm of network weight vectors to avoid over"tting. The results are compared with support vector machines and standard backpropagation. ( 2000(More)
This paper presents a multiobjective approach for the design of electrical distribution networks. The objectives are defined as a monetary cost index (including installation cost and energy losses cost) and a system failure index. The true Pareto-optimal solutions are found with a multiobjective genetic algorithm that employs an efficient variable encoding(More)
This paper presents a new scheme for training MLPs which employs a relaxation method for multi-objective optimization. The algorithm works by obtaining a reduced set of solutions, from which the one with the best generalization is selected. This approach allows balancing between the training error and norm of network weight vectors, which are the two(More)
Paracoccidioides brasiliensis, the etiologic agent of paracoccidioidomycosis, is a dimorphic fungus which is found as mycelia (M) at 26 degrees C and as yeasts (Y) at 37 degrees C, or after the invasion of host tissues. Although the dimorphic transition in P. brasiliensis and other dimorphic fungi is an essential step in the establishment of infection, the(More)
This paper presents a new operator for genetic algorithms that enhances their convergence in the case of nonlinear problems with nonlinear equality constraints. The proposed operator, named CQA (Constraint Quadratic Approximation), can be interpreted as both a local search engine (that employs quadratic approximations of both objective and constraint(More)
This work presents a multiobjective genetic algorithm with a novel feature, the real biased crossover operator. This operator takes into account the function values of the two parents, defining a nonuniform probability for the new individuals’ locations that biases them toward the best parents’ locations. The procedure leads to better estimates of the(More)
This paper addresses the mobile robot motion planning problem in outdoor environments, which are large, sparsely occupied workspaces with uneven terrains. We present results in path planning using an efficient discretization method based on Constrained Delaunay Triangulation (CDT) and classical graph searching algorithms. CDT has been proven to be a good(More)