San Pablo Catholic University
Arequipa, Peru
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Saire J.E.C.,San Pablo Catholic University
ACM International Conference Proceeding Series | Year: 2016

The Evolutionary Algorithms have main features like: population, evolutionary operations (crossover, mate, mutation and others). Most of them are based on randomness and follow a criteria using fitness like selector. The FP-AK-QIEA-R uses probability density function according to best of initial population to sample new population and uses rewarding criteria to sample around the best of every iteration using cumulative density function estimated for Akima interpolation, it was used for mono-objective problems showing good results. The proposal uses the algorithm FP-AKQIEA-R and add Pareto dominance to experiment with multiobjective problems. The performed experiments use some benchmark functions from the literature and initial results shows a promissory way for the algorithm. © 2016 ACM.

Chavez-Fernandez Postigo J.,San Pablo Catholic University
Cuadernos de bioetica : revista oficial de la Asociacion Espanola de Bioetica y Etica Medica | Year: 2015

From a basic terminological clarification, we seek to examine briefly what can be acknowledged as the two biggest attempts of foundation in the Biolaw contemporary area, that of the Kantian tradition and that of the anthropological and metaphysical realism. Through a critical examination of the first one, we attempt to show that only from a freedom or an autonomy assumed from the anthropological and metaphysical realism, is possible to hold a Biolaw as a true impervious limit against the technological power regarding human life and human procreation.

Meza-Lovon G.L.,National University of San Agustín | Meza-Lovon G.L.,San Pablo Catholic University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

Over the last years, the interest in preserving digitally ancient documents has increased resulting in databases with a huge amount of image data. Most of these documents are not transcribed and thus querying operations are limited to basic searching. We propose a novel approach for transcribing historical documents and present results of our initial experiments. Our method divides a text-line image into frames and constructs a graph using the framed image. Then Dijkstra algorithm is applied to find the line transcription. Experiments show a character accuracy of 79.3%. © Springer-Verlag Berlin Heidelberg 2012.

Ludena-Choez J.,San Pablo Catholic University | Ludena-Choez J.,Charles III University of Madrid | Gallardo-Antolin A.,Charles III University of Madrid
PLoS ONE | Year: 2017

Feature extraction for Acoustic Bird Species Classification (ABSC) tasks has traditionally been based on parametric representations that were specifically developed for speech signals, such as Mel Frequency Cepstral Coefficients (MFCC). However, the discrimination capabilities of these features for ABSC could be enhanced by accounting for the vocal production mechanisms of birds, and, in particular, the spectro-temporal structure of bird sounds. In this paper, a new front-end for ABSC is proposed that incorporates this specific information through the non-negative decomposition of bird sound spectrograms. It consists of the following two different stages: short-time feature extraction and temporal feature integration. In the first stage, which aims at providing a better spectral representation of bird sounds on a frame-by-frame basis, two methods are evaluated. In the first method, cepstral-like features (NMF_CC) are extracted by using a filter bank that is automatically learned by means of the application of Non-Negative Matrix Factorization (NMF) on bird audio spectrograms. In the second method, the features are directly derived from the activation coefficients of the spectrogram decomposition as performed through NMF (H_CC). The second stage summarizes the most relevant information contained in the short-time features by computing several statistical measures over long segments. The experiments show that the use of NMF_CC and H_CC in conjunction with temporal integration significantly improves the performance of a Support Vector Machine (SVM)-based ABSC system with respect to conventional MFCC. © 2017 Ludeña-Choez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Caceres J.C.G.,San Pablo Catholic University | Chavez J.R.G.,San Pablo Catholic University
Proceedings - International Conference of the Chilean Computer Science Society, SCCC | Year: 2017

Face recognition is one of the most important field in computer vision, although there are many proposals and research papers still have limitations in real applications where uncontrolled conditions such as illumination, view angle, facial expressions, resolution and image quality, etc. are the main problems. To solve these issues there are a large number of methods for recognition, which can be grouped according to the approach by which the recognition process is addressed, such groups are; holistic methods and featrure based. In this paper we address a feature-based method called Elastic Bunch Graph Matching (EBGM) which is appropriate for an uncontrolled environment for its tolerance to changing background and certain variations of pose, also by having a lower sensitivity variations of illumination which is one of the weaknesses in the holistic methods, which compared to them EBGM without any modification obtained results alongside well-known methods as Principal Component Analysis (PCA). EBGM has several parameters that can be configured and most of the works in literature uses the default settings of the original author. In this respect this paper presents modifications to these parameters as regards the number of models, illumination enhancement in the preprocessing phase, the configurations Gabor masks and modifying the similarity function. Finally we corroborate the existence of improvements on our experimental results. © 2016 IEEE.

Reymer J.M.A.,San Pablo Catholic University | Valdivia Y.J.T.,San Pablo Catholic University
Proceedings - International Conference of the Chilean Computer Science Society, SCCC | Year: 2017

In this paper, a generalization of the original Quantum-Inspired Evolutionary Algorithm (QIEA): the Generalized Quantum-Inspired Evolutionary Algorithm (GQIEA) is proposed. Like QIEA, GQIEA is also based on the quantum computing principle of superposition of states, but extending it not only to be used for binary values {0, 1}, but for any finite set of values {1,⋯, n}. GQIEA, as any other quantum inspired evolutionary algorithm, defines an own quantum individual, an evaluation function and population operators. As in QIEA, GQIEA also defines a generalized Q-gate operator, which is a variation operator to drive the individuals toward better solutions. To demonstrate its effectiveness and applicability, the proposal will be applied to the Knapsack Problem (KP), a classic combinatorial optimization problem. Results show that GQIEA has a good performance even with a small population. © 2015 IEEE.

Flores M.A.,San Pablo Catholic University | Santisteban J.,San Pablo Catholic University
Proceedings of the 2016 IEEE 23rd International Congress on Electronics, Electrical Engineering and Computing, INTERCON 2016 | Year: 2016

The Network Address Translation (NAT) is a mechanism used almost for every user on the internet, primarily to alleviate the exhaustion of IPv4 address space by allowing multiple hosts to share a public/Internet address. The NAT allow to establish TCP communications if the communication start from internal NAT, but does not allow communication if it start from the public internet, external NAT. This is call The NAT traversal problems. It cause that communications among peers relay on a third intermediary computer for the whole communication. Been this a security issue as the third intermediary can get a copy of the communication and also make the communication slower as it need to go through the third computer. This is the case for any p2p, VoIP, live games among others internet applications. In this article we present a novel mechanism to establish a communication among peers in which peers are behind a NAT without using a third intermediary for the whole communication. © 2016 IEEE.

Mayhua-Lopez E.,San Pablo Catholic University | Gomez-Verdejo V.,Charles III University of Madrid | Figueiras-Vidal A.R.,Charles III University of Madrid
Information Fusion | Year: 2015

Boosting algorithms pay attention to the particular structure of the training data when learning, by means of iteratively emphasizing the importance of the training samples according to their difficulty for being correctly classified. If common kernel Support Vector Machines (SVMs) are used as basic learners to construct a Real AdaBoost ensemble, the resulting ensemble can be easily compacted into a monolithic architecture by simply combining the weights that correspond to the same kernels when they appear in different learners, avoiding to increase the operation computational effort for the above potential advantage. This way, the performance advantage that boosting provides can be obtained for monolithic SVMs, i.e., without paying in classification computational effort because many learners are needed. However, SVMs are both stable and strong, and their use for boosting requires to unstabilize and to weaken them. Yet previous attempts in this direction show a moderate success. In this paper, we propose a combination of a new and appropriately designed subsampling process and an SVM algorithm which permits sparsity control to solve the difficulties in boosting SVMs for obtaining improved performance designs. Experimental results support the effectiveness of the approach, not only in performance, but also in compactness of the resulting classifiers, as well as that combining both design ideas is needed to arrive to these advantageous designs. © 2014 Elsevier B.V.All rights reserved.

Braga S.L.,Pontifical Catholic University of Rio de Janeiro | Milon J.J.,San Pablo Catholic University
International Journal of Heat and Mass Transfer | Year: 2012

An experimental device was developed to study dendritic ice growth in supercooled water inside cylindrical capsules. The capsule materials investigated were acrylic, PVC (polyvinyl chloride), bronze and aluminum. The internal diameter of all the capsules was 45 mm. The results indicate that dendritic ice appears only in supercooled water at the start of nucleation. Blockage by dendritic ice growth was classified according to the capsule material and the coolant temperature. Total blockage (100%) and partial blockage (25%, 50% and 75%) was observed. Dendritic ice growth was shown and analyzed in photographic sequences. © 2012 Elsevier Ltd. All rights reserved.

Ludena-Choez J.,Charles III University of Madrid | Ludena-Choez J.,San Pablo Catholic University | Gallardo-Antolin A.,Charles III University of Madrid
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

In this paper, we propose a new front-end for Acoustic Event Classification tasks (AEC). First, we study the spectral contents of different acoustic events by applying Non-Negative Matrix Factorization (NMF) on their spectral magnitude and compare them with the structure of speech spectra. Second, from the findings of this study, we propose a new parameterization for AEC, which is an extension of the conventional Mel Frequency Cepstrum Coefficients (MFCC) and is based on the high pass filtering of acoustic event spectra. Also, the influence of different frequency scales on the classification rate of the whole system is studied. The evaluation of the proposed features for AEC shows that relative error reductions about 12% at segment level and about 11% at target event level with respect to the conventional MFCC are achieved. © 2013 Springer-Verlag Berlin Heidelberg.

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