Mixture-based probabilistic graphical models for the partial label ranking problem

The Label Ranking problem consists in learning preference models from training datasets labeled with a ranking of class labels, and the goal is to predict a ranking for a given unlabeled instance. In this work, we focus on the particular case where both, the training dataset and the prediction given as output allow tied labels (i.e., there is no particular preference among them), known as the Partial Label Ranking problem. In particular, we propose probabilistic graphical models to solve this problem. As far as we know, there is no probability distribution to model rankings with ties, so we transform the rankings into discrete variables to represent the precedence relations (precedes, ties and succeeds) among pair of class labels (multinomial distribution). In this proposal, we use a Bayesian network with Naive Bayes structure and a hidden variable as root to collect the interactions among the different variables (predictive and target). The inference works as follows. First, we obtain the posterior-probability for each pair of class labels, and then we input these probabilities to the pair order matrix used to solve the corresponding rank aggregation problem. The experimental evaluation shows that our proposals are competitive (in accuracy) with the state-of-the-art Instance Based Partial Label Ranking (nearest neighbors paradigm) and Partial Label Ranking Trees (decision tree induction) algorithms

Mixture-Based Probabilistic Graphical Models for the Label Ranking Problem

The goal of the Label Ranking (LR) problem is to learn preference models that predict the preferred ranking of class labels for a given unlabeled instance. Different well-known machine learning algorithms have been adapted to deal with the LR problem. In particular, fine-tuned instance-based algorithms (e.g., k-nearest neighbors) and model-based algorithms (e.g., decision trees) have performed remarkably well in tackling the LR problem. Probabilistic Graphical Models (PGMs, e.g., Bayesian networks) have not been considered to deal with this problem because of the difficulty of modeling permutations in that framework. In this paper, we propose a Hidden Naive Bayes classifier (HNB) to cope with the LR problem. By introducing a hidden variable, we can design a hybrid Bayesian network in which several types of distributions can be combined: multinomial for discrete variables, Gaussian for numerical variables, and Mallows for permutations. We consider two kinds of probabilistic models: one based on a Naive Bayes graphical structure (where only univariate probability distributions are estimated for each state of the hidden variable) and another where we allow interactions among the predictive attributes (using a multivariate Gaussian distribution for the parameter estimation). The experimental evaluation shows that our proposals are competitive with the start-of-the-art algorithms in both accuracy and in CPU time requirements

Disaster Response Project Scheduling Problem: A Resolution Method based on a Game-Theoretical Model

We present a particular disaster response project scheduling problem (DRPSP) motivated by Fukushima’s nuclear accident of Japan in 2011. We describe the problem as MPS;R,N|prec, dn|Pckf(rk(S)) by using Hartmann and Briskornscheme and formulate a mixed integer linear programming (MILP) model. Due to the NP-hardness of the problem, we propose a resolution method based on game theory.This method associates the DRPSP to a non-cooperative game model, such thatgame solution is a feasible solution of the problem. In order to explore the potentialof the proposed model and the performance of the resolution method, computationalexperiments are carried out. The results of resolution method show on average, thatthe method finds a feasible solution with a difference of 15.44% with respect to optimalsolution within one percent of the time required by the MILP over GAMS22.7.2/CPLEX 11.0

La falla de Tíscar: su significado en la terminación sudoeste del arco Prebético

10 páginas, 11 figuras, 1 tabla.[EN] The Tíscar fault, located towards the SW end of the Prebetic arc, is an important feature within the Betic External Zone which contributed to the separation of two different geologic domains. This fault affected the Mesozoic and Tertiary cover detached from the Palaeozoic basement and was developed as consequence of the blockage of the thrust sheets of the western border of the arc, because they could not advance farther over the basement situated progressively in a shallower position. Hence, this fault encouraged the continuation of the NW displacements in the western block, formed by Subbetic olistostromic masses and part of the Prebetic situated in the end of the arc. Although the Tíscar fault has been defined by one main line, there are in fact other parallel faults that form a broad fault zone. Its displacement began during the late Miocene and continued till Pliocene, within a near N-S compressive setting with a perpendicular extension.[ES] La falla de Tíscar, localizada en la terminación SO del arco Prebético, es un rasgo importante dentro de la Zona Externa Bética, donde ha contribuido a la separación de dos dominios geológicos diferentes. Esta falla afectó a la cobertera mesozoica y terciaria despegada del basamento paleozoico y se formó como consecuencia de que los cabalgamientos del borde occidental del arco quedaron bloqueados al no poder avanzar más sobre el basamento cada vez menos profundo. Entonces la falla permitió la continuación de los movimientos hacia el NO de su bloque occidental formado por materiales del Subbético, dispuesto en masas olistostrómicas, e incluso parte del propio Prebético del extremo del arco. Aunque la falla de Tíscar se ha definido por su traza principal, existen otras paralelas que en conjunto forman una amplia zona. Sus movimientos iniciados en el Mioceno superior continuaron hasta el Plioceno, en un contexto de compresión N-S y extensión perpendicular.Este estudio se ha financiado a través de los proyectos BTE2001-5230-E, CGL200401636/BTE, CGL2004-03333/ BTE, CGL2005-01520/BTE y BTE2001-5230-E y los grupos de la Junta de Andalucía RNM 163 y 217.Peer reviewe

Contaminación sonora en la ciudad de Barranca-Lima-Perú

Several publications report that the health effects of noise pollution are of medical and social importance; causing in people effects such as stress, anxiety, cardiovascular problems, cognitive impairment and decreased physical condition among others. The objective of the investigation was to monitor the sound with measurements in situ in Barranca city, Lima - Peru and to identify the decibels to which some special and commercial protection zones would be subject. The sound recording was done with a sonometer, in the fronts of educational, health center and commercial areas. The results showed that the sound level exceeded the maximum tolerable limit of 50 dB established in Supreme Decree No. 085-2003-PCM, in special in protection areas such as Ventura Ccalamaqui College, Barranca Cajatambo Hospital and mixed areas such as market and commercial center. In conclusion, the noise pollution in the areas evaluated in Barranca city exceeds the established maximum limits, obtaining maximums of 79.32 ± 2.07 dB, especially on the first working day at the beginning of the week; high noise levels would cause adverse effects on people's health.Diversas publicaciones, reportan efectos dañinos por contaminación sonora siendo de importancia médica y social; que provocan en las personas efectos como estrés, ansiedad, problemas cardiovasculares, deterioro cognitivo y disminucion del estado fisico entre otros. El objetivo de la investigación fue monitorear el sonido in situ en la ciudad de Barranca, Lima – Perú e identificar los decibeles al cual estarían sometidos algunas zonas de protección especial y comercial. El registro de sonido se realizó con un sonometro, en los frontis de instituciones educativas, centros de salud, y zonas comerciales. Los resultados mostraron que el nivel sonoro superó el límite máximo tolerable de 50 dB establecido en el Decreto Supremo Nº 085-2003-PCM, en las zonas de protección especial como el Colegio Ventura Ccalamaqui y Hospital de Barranca Cajatambo y zonas mixtas como mercado y centro comercial. En conclusión, la contaminación sonora en las zonas evaluadas en la ciudad de Barranca, supera los límites máximos establecidos, obteniéndose máximos de 79,32±2,07 dB, sobre todo el primer día laborable en inicio de semana; los altos niveles sonoros provocarían consecuencias negativas en la salud

Aprovechamiento integral de Eucalyptus globulus en un esquema de biorrefinería en doble etapa

Se han aplicado dos tratamientos previos al proceso de pasteado etanol-sosa sobre madera de Eucalyptus globulus para evaluar su influencia sobre las propiedades de las pastas celulósicas obtenidas. Se aplica una primera etapa optimizada de autohidrólisis para maximizar la extracción de derivados hemicelulósicos preservando el glucano, seguida de una deslignificación enzimática mediante un sistema lacasa/mediador (siringaldehído). Se aplican diseños experimentales para la optimización de los procesos. Las condiciones de operación óptimas en la etapa de deslignificación enzimática han sido: concentración de lacasa 18,5 U/g, concentración de siringaldehído 1,5 %, temperatura 45 ºC y tiempo de operación 60 min., con las cuales se alcanza una eliminación del 16,8 % de la lignina existente en la materia prima y se afecta ligeramente al glucano (conservando entre el 82,2 % y 89,7 % del glucano inicial). Paralelamente se obtienen dos fases líquidas valorizables, ricas en derivados hemicelulósicos y polifenólicos. En este esquema de proceso para obtención de pasta celulósica etanol-sosa a partir de madera eucalipto requiere una menor concentración de reactivos químicos, menores tiempos de operación y temperaturas más bajas, lo que supone una mejora económica y medioambiental respecto del proceso convencional de pasteado