Juan Méndez

University of Las Palmas de Gran Canaria | ULPGC · Department of Computer Sciences and Systems

The more important difference between Riemann and pseudo-Riemann manifolds is the metric signature and its theoretical consequences. The practical application for Physics Theories becomes often impossible due to the signature consequences. Eg., some of the rich results in Riemann Geometry and Topology become invalid for Physics if they are based on...

The Riemannian geometry is one of the main theoretical pieces in Modern Mathematics and Physics. The study of Riemann Geometry in the relevant literature is performed by using a well defined analytical path. Usually it starts from the concept of metric as the primary concept and by using the connections as an intermediate geometric object, it is ac...

Some algorithms in pattern recognition and machine learning as neighborhood-based classification and dataset condensation can be improved with the use of Voronoi tessellation. This paper shows the weakness of some existing algorithms of tessellation to deal with high-dimensional datasets. The use of linear programming can improve the tessellation p...

Some algorithms in Pattern Recognition and Machine Learning as neighborhood-based classification and dataset condensation can be improved with the use of Voronoi tessellation. The paper shows the weakness of some existing algorithms of tessellation to deal with high dimensional datasets. The use of linear programming can improve the tessellation pr...

In this paper an architecture for an estimator of short-term wind farm power is proposed. The estimator is made up of a Linear Machine classifier and a set of k Multilayer Perceptrons, training each one for a specific subspace of the input space. The splitting of the input dataset into the k clusters is done using a k-means technique, obtaining the...

In this paper some experiments have been realized to test how the introduction of variable selection has an effect on the predictor performance in short-term wind farm power prediction. Variable selection based on Kraskov estimation of the mutual information will be used due to its capability to deal with sets of continuous random variables. A Mult...

Template matching is a traditional technique of Computer Vision whose advantages and disadvantages are known. However, advances in computer hardware allow computing it effectively with the use of SIMD instruction set, GPUs or multi-core systems. The computation of that low-level primitive in sub millisecond scale would improve high theoretical meth...

The use of renewable energy sources (RES) in electricity generation has many economical and environmental advantages, but has a downside in the instability and unpredictability introduced into the public electric systems. High variable energies such as wind power have a lack of stability and, to avoid short-term variations in power supplied to the...

This paper shows a method to compute the chord and twist distributions in wind power blades. The distributions are computed to maximize the mean expected power depending on the Weibull wind distribution at a specific site. This approach avoids assumptions about optimal attack angle related to the ratio between the lift to drag coefficients. To opti...

Many published studies in wind power forecasting based on Neural Networks have provided performance factors based on error criteria. Based on the standard protocol for forecasting, the published results must provide improvement criteria over the persistence or references models of its same place. Persistence forecasting is the easier way of predict...

In this work local binary patterns based focus measures are presented. Local binary patterns (LBP) have been introduced in computer vision tasks like texture classification or face recognition. In applications where recognition is based on LBP, a computational saving can be achieved with the use of LBP in the focus measures. The behavior of the pro...

Most face recognition systems are based on some form of batch learning. Online face recognition is not only more practical, it is also much more biologically plausible. Typical batch learners aim at minimizing both training error and (a measure of) hypothesis complexity. We show that the same minimization can be done incrementally as long as some f...

This paper describes a technique for associating a set of symbols with an event in the context of knowledge discovery in database or data mining. The set of symbols is related to the keywords in a database which is used as an implicit knowledge source. The aim of this approach is to discover the significant keyword groups which best represent the e...

This paper describes some,simple but useful computer,vision techniques for human-robot interaction. First, an omnidirectional camera setting is described that can detect people in the surroundings of the robot, giving their angular positions and a rough estimate of the distance. The device can be easily built with inexpensive components. Second, we...

A Procedure for fast pattern matching in protein sequences is presented. It uses a biological metric, based on the substitution matrices as PAM or BLOSUM, to compute the matching. Biological sensitive pattern matching does pattern detection according to the available empirical data about similarity and affinity relations between amino acids in prot...

Social robots are receiving much interest in the robotics community. The most important goal for such robots lies in their interaction capabilities. An attention system is crucial, both as a filter to center the robot’s perceptual resources and as a mean of letting the observer know that the robot has intentionality. In this paper a simple but flex...

This paper describes an approach for detection of frontal faces in real time (20–35Hz) for further processing. This approach makes use of a combination of previous detection tracking and color for selecting interest areas. On those areas, later facial features such as eyes, nose and mouth are searched based on geometric tests, appearance verificati...

A procedure to map score matrices in n-dimensional spaces is presented. Score or substitutions matrices are used as similarity-like measure between amino acid in protein alignment procedures. The first stage of heuristic local alignments procedures as FASTA and BLAST uses local matching of very short sequences, also named k-tuples. By using L1 metr...

In this paper we will present Eldi, a mobile robot that has been in operation at the Elder Museum of Science and Technology at Las Palmas de Gran Canaria since December 1999. This is an ongoing project that was organized in three different stages of which only the first one has been accomplished. The initial phase, termed “The Player”, the second s...

In this paper we will present Eldi, a mobile robot that has been in daily operation at the Elder Museum of Science and Technology at Las Palmas de Gran Canaria since December 1999. The system that controls Eldi and the rest of the installation has been conceived as a set of agents that interact by means of discrete events. This is an ongoing projec...

In this paper we will present Eldi, a mobile robot that has been in daily operation at the Elder Museum of Science and Technology at Las Palmas de Gran Canaria since December 1999. This is an ongoing project that was organized in three different stages, describing here the one that has been accomplished. The initial phase, termed "The Player", the...

No positive result has been obtained on the magnetic monopoles search. This allows to consider different theoretical approaches as the proposed in this paper, developed in the framework of the Einstein General Relativity. The properties of second rank skew-symmetrical fields are the basis of electromagnetic theories. In the space-time the Hodge dua...

Although many different vision algorithms and systems have been developed so far, integration into a complex intelligent control architecture of a mobile robot is in most cases an open problem. In this paper we describe the integration of different vision ...

In this paper we propose a general layered model for the design of perception-action system. We discuss some desirable properties such a system must support to meet the severe constrains imposed by the expected behaviour of reactive systems. SVEX, a knowledge-based multilevel system, is used as a test prototype to implement and evaluate those consi...

In this work a measure called GD is presented for attribute selection. This measure is defined between an attribute set and a class and corresponds to a generalization of the Mántaras distance that allows to detect the interdependencies between attributes. In the same way, the proposed measure allows to order the attributes by importance in the def...

A new measure for attribute selection, called GD, is proposed. The GD measure is based on Information Theory and allows to detect the interdependence between attributes. This measure is based on a quadratic form of the Mntaras distance and a matrix called Transinformation Matrix. In order to test the quality of the proposed measure, it is compared...

This paper describes a tool to aid the development of computer vision applications for pixel-level diagnosis. A conceptual framework for constructing pixel processors is described. The proposed tool is based on two domains: one deals with numerical images, named features, and the other deals with symbolic images, named classes. A reduced set of ima...

A new methodology has been developed for the comparative analysis of different contour characterization methods in the context of a structural approach for an artificial vision system. This methodology has been designed for testing the description of contour segments using characterization methods that have been used in applications dealing with is...

The characterization techniques of forms can be usually classified grosso modo between global and local techniques. The complexity of the images to be analized imposes strong limitations to the freedom of choice about the model of description to be used. So the global techniques are used in enviroments where the objects to be classified are simple...

This paper intends to introduce a new alternative to multilink systems computer/terminal, the aim of this alternative is double: increasing data flow and decreasing installation costs. Its most immediate field of application would be remote point-to-point links, even though local networks could also be adecuately handled allowing linking several te...

The paper shows the application of the multidimensional scaling to discover the intrinsic dimensionality of the substitution matrices. These matrices are used in Bioinformatics to compare amino acids in the alignment procedures. However, the methodology can be used in other applications to discover the intrinsic dimensionality of a wide class of sy...

In this paper a processing methodology is introduced for the segment or intermediate level in the context of knowledge-based computer vision systems. The proposed methodology demonstrates how using simple Fuzzy Logic concepts it is possible to associate symbolic descriptions to the entities of this level. It provides with the basic mechanisms for p...