Jacobi-Type orthogonal polynomials: holonomic equation and electrostatic interpretation

16 pages, no figures.-- MSC2000 code: 33C47.MR#: MR2410226 (2009c:33029)In this contribution we study some pertubation of the Jacobi weight function by adding a mass point at x = 1, one of the ends of the interval supporting such a measure. We find the explicit expression of the corresponding orthogonal polynomials as well as the holonomic equation that such polynomials satisfy. Next, we analyze the location of their zeros and, finally, we give an electrostatic interpretation of them.The work of the second author (FM) has been supported by Dirección General de investigación, Ministerio de Educación y Ciencia of Spain, grant MTM2006-13000-C03-02.Publicad

Perturbations of Laguerre-Hahn functional: modification by the derivative of a Dirac delta

19 pages, no figures.-- MSC2000 code: 33C47.MR#: MR2492206 (2010a:33031)Zbl#: Zbl pre05509604In this paper, we consider a perturbation of a Laguerre-Hahn functional by adding a derivative of a Dirac delta. This transformation leaves invariant the family of Laguerre-Hahn linear functionals. We shall also analyse the class of the perturbed linear functional. Finally, we illustrate these perturbations by adding the derivative of a Dirac delta to the first kind associated functional of the classical Laguerre functional. The expression of the new orthogonal polynomials is obtained.The work of the first and second author has been supported by Comunidad de Madrid-Universidad Carlos III de Madrid, grant CCG07-UC3M/ESP-3339. The work of the second author has been supported by Dirección General de Investigación, Ministerio de Educación y Ciencia of Spain, grant MTM2006-13000-C03-02.Publicad

Sobre (1, 1) pares coherentes simétricos y polinomios ortogonales Sobolev: un algoritmo para calcular coeficientes de Fourier

In the pioneering paper [13], the concept of Coherent Pair was introduced by Iserles et al. In particular, an algorithm to compute Fourier Coefficients in expansions of Sobolev orthogonal polynomials defined from coherent pairs of measures supported on an infinite subset of the real line is described. In this paper we extend such an algorithm in the framework of the so called Symmetric (1, 1)-Coherent Pairs presented in [8].En el artículo pionero [13], fue introducido el concepto de Par Coherente por Iserles et al. En particular, allí es descrito un algoritmo para calcular coeficientes de Fourier de expansiones de polinomios ortogonales de tipo Sobolev definidos a partir de pares de medidas coherentes soportadas en un subconjunto infinito de la recta real. En esta contribución extendemos tal algoritmo en el contexto de los llamados Pares Simétricos (1, 1)−Coherentes presentados en [8]

The effect of verbal instructions in contingency learning depends on the time available to process the cue: evidence in favor of associative models

Much of the research in human contingency learning has tried to dissociate associative and inferential processes. One feature that has been regarded as relevant for these dissociations is the time available to process the cue. A brief presentation of the cue may facilitate the activation of associative processes whereas a long one may favor the activation of inferential processes. The two experiments reported here used a two-phase task. In Phase 1, four different cue-outcome relationships were programmed. In Phase 2, two of these relationships were changed. Participants knew about some of these changes through verbal instructions. The effect of these instructions was measured during Phase 2 in two groups that differed in the time available to process the cue, either 250 or 1500 ms. The results showed that the control of performance produced by verbal instructions differed depending on the time available to process the cue. Only in the 1500 ms group, the verbal instructions were able to affect what it had been learnt during Phase 1. Thus, the results are consistent with the hypothesis that a brief presentation of the cue during Phase 2 facilitates the activation of associative processesUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Proyecto MICIN Proyecto PSI 2011-2466

Bond strength of galvanized steel : experimental and numerical study based on pull-out tests

Congreso celebrado en la Escuela de Arquitectura de la Universidad de Sevilla desde el 24 hasta el 26 de junio de 2015.The construction of more durable structures is becoming a mandatory requirement. Different alternatives are followed in reinforced concrete structures, as the use of galvanized reinforcement to increase the service life. Due to the fact that the interaction between concrete and galvanized steel is different from the carbon steel case, the bond strength might call into question. The present article studies the bond stress development of conventional and hot-dip galvanized steel reinforcement embedded in concrete made with Ordinary Portland Cement (OPC). Results indicate that maximum bond stress measured for galvanized steel is similar to that of conventional reinforcement. Furthermore, the numerical model developed with ABAQUS notably reproduces the contact between concrete and galvanized steel with the help of the experimental pull out tests carried out, showing a practical implementation for future structural element analysis

Hierarchical clustering for smart meter electricity loads based on quantile autocovariances

In order to improve the efficiency and sustainability of electricity systems, most countries worldwide are deploying advanced metering infrastructures, and in particular household smart meters, in the residential sector. This technology is able to record electricity load time series at a very high frequency rates, information that can be exploited to develop new clustering models to group individual households by similar consumptions patterns. To this end, in this work we propose three hierarchical clustering methodologies that allow capturing different characteristics of the time series. These are based on a set of “dissimilarity” measures computed over different features: quantile auto-covariances, and simple and partial autocorrelations. The main advantage is that they allow summarizing each time series in a few representative features so that they are computationally efficient, robust against outliers, easy to automatize, and scalable to hundreds of thousands of smart meters series. We evaluate the performance of each clustering model in a real-world smart meter dataset with thousands of half-hourly time series. The results show how the obtained clusters identify relevant consumption behaviors of households and capture part of their geo-demographic segmentation. Moreover, we apply a supervised classification procedure to explore which features are more relevant to define each cluster.This work was supported in part by the Spanish Government through Project under Grant MTM2017-88979-P, and in part by the Fundación Iberdrola through “Ayudas a la Investigación en Energía y Medio Ambiente 2018.” The work of Andrés M. Alonso was supported in part by the Spanish Government through Project under Grant ECO2015-66593-P. Paper no. TSG-01702-2019

Airflow patterns through a sliding door during opening and foot traffic in operating rooms

Producción CientíficaIt is common practice for operating rooms (OR) to have more pressure than the adjacent enclosures. This is to prevent the entry of potentially contaminated air and the consequent risk of wound infection. However, when the OR door is opened the pressure difference between the two areas disappears and can cause containment failures. If a person enters or leaves the OR during door operation, additional perturbations are also generated in the airflow pattern in the doorway. In this paper, instantaneous airflows are measured during the passage of a person through a sliding door in a real OR with the HVAC system working under operating conditions. An ultrasonic anemometer that measures the magnitude and direction of the instantaneous air velocity in the doorway is used. Results show that, even though the OR has a sliding door and an initial overpressure of 20 Pa, together with what is, a priori, a good HVAC system control strategy, a small volume of air enters the OR during a cycle of door opening and closing even without the passage of a person. Furthermore, if a person walks through the door the volume of air entering the OR is higher, especially if the person enters the OR. © 2016 Elsevier LtdMinistry of Economy and Competiveness project DPI2014-55357-C2-1-R cofinanced by the European Regional Development Fund (ERDF)

Diferencias de los valores de eficacia en el contraataque y replegamiento defensivo entre equipos ganadores en waterpolo masculino y femenino

El presente estudio pretende alcanzar dos objetivos: el primero, averiguar los valores de eficacia en las microsituaciones de juego en el contraataque y replegamiento defensivo, y el segundo, examinar la relación entre los valores de eficacia en equipos con la condición de ganador al finalizar el partido y en ambos sexos. Para la parte empírica se grabaron en vídeo la totalidad de los partidos de waterpolo disputados en el X Campeonato del Mundo celebrado en Barcelona durante el mes de Julio de 2003. Tras la observación y análisis de las grabaciones mencionadas, se valoró mediante el uso de coeficientes la eficacia en todas las microsituaciones de juego en el contraataque y replegamiento defensivo, obteniendo unos valores de eficacia. Se revelaron diferencias entre ambos sexos en la condición de ganador al final del partido en los siguientes coeficientes: precisión (,012) y posibilidad (,013) en el repliegue defensivo uno y otro; tomando como referencia un valor de p < ,05. Para concluir, decir que en dos de los catorce coeficientes de eficacia propuestos para evaluar las microsituaciones de juego en el contraataque y replegamiento defensivo en waterpolo existen diferencias significativas entre sexos en equipos con la condición de ganador al finalizar el partido

Diferències dels valors d’eficàcia en el contraatac i el replegament defensiu entre equips guanyadors en waterpolo masculí i femení

Aquest estudi pretén d’assolir dos objectius: el primer, esbrinar els valors d’eficàcia en les microsituaciones de joc  en el contraatac i el replegament defensiu, i el segon, examinar la relació entre els valors d’eficàcia en equips amb la condició de guanyador en finalitzar el partit i en ambdós sexes. Per a la part empírica es van gravar en vídeo la totalitat dels partits de waterpolo disputats en el X Campionat del Món celebrat a Barcelona durant el mes de juliol del 2003. Després de l’observació i l’anàlisi dels enregistraments esmentats, es va valorar, mitjançant l’ús de coeficients, l’eficàcia en totes les microsituacions de joc en el contraatac i el replegament defensiu; d’aquesta forma es van obtenir uns valors d’eficàcia. Es van revelar diferències entre tots dos sexes en la condició de guanyador al final del partit en els coeficients següents: precisió (,012) i possibilitat (,013) en el replegament defensiu l’un i l’altre; prenent com a referència un valor de p < ,05. Finalment, cal dir que en dos dels catorze coeficients d’eficàcia proposats per avaluar les microsituacions de joc en el contraatac i el replegament defensiu en waterpolo, hi ha diferències significatives entre sexes en equips amb la condició de guanyador en finalitzar el partit