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Nova Londrina, Brazil

Valle M.E.,University of Londrina | Vicente D.M.G.,West Parana State University
Journal of Mathematical Imaging and Vision | Year: 2012

Sparsely connected autoassociative lattice memories (SCALMs) are very general models defined on complete lattices, a mathematical structure which is obtained by imposing some ordering on a set. They are computationally cheaper and mathematically simpler than "traditional" models and other memories such as the original autoassociative morphological memories (AMMs) of Ritter and Sussner because they only compute maximums and minimums. This paper provides theoretical results on SCALMs defined on a general complete lattice as well as an application of these memories for the storage and recall of color images. Precisely, we characterize the recall phase of SCALMs in terms of their fixed points. Then, we show that any endomorphic lattice polynomial-a concept that generalizes the notion of lattice polynomial of Birkhoff-on the fundamental memory set represents a fixed point of the SCALMs. Also, we discuss the relationship between SCALMs and the original AMMs. Finally, we provide some experimental results on the performance of SCALMs, defined on different color lattices, for the reconstruction of color images corrupted by either Gaussian or impulsive noise. © Springer Science+Business Media, LLC 2011. Source

Valle M.E.,University of Londrina
Information Sciences | Year: 2010

Implicative fuzzy associative memories (IFAMs) are single layer feedforward fuzzy neural networks whose synaptic weights and threshold values are given by implicative fuzzy learning. Despite an excellent tolerance with respect to either pasitive or negative noise, IFAMs are not suited for patterns corrupted by mixed noise. This paper presents a solution to this problem. Precisely, we first introduce the class of finite IFAMs by replacing the unit interval by a finite chain L. Then, we generalize both finite IFAMs and their dual versions by means of a permutation on L. The resulting models are referred to as permutation-based finite IFAMs (π-IFAMs). We show that a π-IFAM can be viewed as a finite IFAM, but defined on an alternative lattice structure (L,). Thus, π-IFAMs also exhibit optimal absolute storage capacity and one step convergence in the autoassociative case. Furthermore, computational experiments revealed that a certain π-IFAM, called Lukasiewicz πμ-IFAM, outperformed several other associative memory models for the reconstruction of gray-scale patterns corrupted by salt and pepper noise. © 2010 Published by Elsevier Inc. Source

Valle M.E.,University of Londrina | Sussner P.,University of Campinas
Pattern Recognition Letters | Year: 2013

In recent years, lattice computing has emerged as a new paradigm for processing lattice ordered data such as intervals, Type-1 and Type-2 fuzzy sets, vectors, images, symbols, graphs, etc. Here, the word ''lattice'' refers to a mathematical structure that is defined as a special type of a partially ordered set (poset). In particular, a complete lattice is a poset that contains the infimum as well as the supremum of each of its subsets. In this paper, we introduce the quantale-based associative memory (QAM), where the notion of a quantale is defined as a complete lattice together with a binary operation that commutes with the supremum operator. We show that QAMs can be effectively used for the storage and the recall of color images. © 2013 Elsevier B.V. All rights reserved. Source

Bonifacio A.L.,University of Londrina | Moura A.V.,University of Campinas
Proceedings of the ACM Symposium on Applied Computing | Year: 2014

Test suite generation for Finite State Machines (FSMs) has been largely investigated. Here, we describe necessary and sufficient conditions for m-completeness of test suites when the specification and implementation are modeled as FSMs. Many earlier works imposed several conditions upon the specification or on the implementation models. We impose weak a priori restrictions on the models. In particular, we do not require reduced models nor complete specifications. Source

Marco P.H.,University of Campinas | Poppi R.J.,University of Campinas | Scarminio I.S.,University of Londrina | Tauler R.,CSIC - Institute of Environmental Assessment And Water Research
Food Chemistry | Year: 2011

The major anthocyanin pigments extracted from Hibiscus acetosella flower were investigated by UV-Vis spectroscopy and multivariate curve resolution-alternating least squares (MCR-ALS). Pure spectra and kinetic of the species present at different pH values were recovered for anthocyanins transformation and degradation products, found with and without UV radiation exposure. In the absence of UV radiation, up to seven different species were detected and by UV radiation exposure, this number increased to up to nine. The species detected in the absence of radiation were also detected when pigments samples were exposed to UV radiation, where degradation occurred faster and two new species appear. The kinetic profiles obtained at different pH values allowed the proposal of a reaction mechanism and pathway. © 2010 Elsevier Ltd. Source

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