Visitas a las páginas de una web docente universitaria

El trabajo estudia las visitas recibidas durante un año y medio por las diferentes páginas de una web utilizada como herramienta complementaria para la docencia de una materia en una universidad presencial. Encuentra que dicho número es mayor, aunque de mThe paper studies the visits received over a year and a half by different web-sites used as complementary tools for the teaching of a non-distance university course. The number of visits is greater, although not significantly, to sites containing theoret

Optimal priority ordering in PHP production of multiple part-types in a failure-prone machine

This note deals with the problem of minimising the expected sum of quadratic holding and shortage inventory costs when a single, failure-prone machine produces multiple part-types. Shu and Perkins (2001) introduce the problem and, by restricting the set of control policies to the class of prioritised hedging point (PHP) policies, establish simple, analytical expressions for the optimal hedging points provided that the priority ordering of the part-types is given. However, the determination of an optimal priority ordering is left by the authors as an open question. This leaves an embedded sequencing problem which we focus on in this note. We define a lower bound for the problem, introduce a test bed for future developments, and propose three dynamic programming approaches (with or without the lower bound) for determining the optimal priority orderings for the instances of the test bed. This is an initial step in a research project aimed at solving the optimal priority ordering problem, which will allow evaluating the performance of future heuristic and metaheuristic proceduresPeer ReviewedPostprint (published version

Fisher information of special functions and second-order differential equations

We investigate a basic question of information theory, namely the evaluation of the Fisher information and the relative Fisher information with respect to a nonnegative function, for the probability distributions obtained by squaring the special functions of mathematical physics which are solutions of second-order differential equations. Emphasis is made in the Nikiforov-Uvarov hypergeometric-type functions. We obtain explicit expressions for these information-theoretic properties via the expectation values of the coefficients of the differential equation. We illustrate our approach for various special functions of physico-mathematical interest

Correlation between impact factor and public availability of published research data in information science & library science journals

Trabajo presentado a la 15th International Society of Scientometrics and Informetrics Conference, celebrada en Estambúl (Turquia) del 29 de junio al 4 de julio de 2015.Scientists continuously generate research data but only a few part of them are published. If these data were accessible and reusable, researchers could examine them and generate new knowledge. Currently, the barriers to data sharing are phased out and public research organizations are demanding ever more insistently that publications resulting from publicly funded projects and data that support them should be published in open (Savage & Vickers, 2009). The purpose of this work is: a) to analyse policies concerning open availability of raw research data in journals in the Information Science & Library Science (ISLS); and b) to determine whether there is a correlation between the impact factor and policies of these journals concerning storage and reuse of scientific data.This work has benefited from assistance by the National R+D+I of the Ministry of Economy and Competitiveness of the Spanish Government (CSO2012-39632-C02-01) and Prometeo Program for excellent research groups of Generalitat Valenciana (GVPROMETEO2013-041).Peer Reviewe

Estudio sobre la mortalidad en Ecuador relacionada con factores de la dieta

Diet is an important factor related to the development of numerous diseases. In developing countries like Ecuador, this aspect is not considered as priority however, the study of the incidence of certain diet-related diseases could help to assess consumption habits of a country from a Public Health perspective and support national nutrition policies and programs. The objective the present study is to investigate the mortality rate of certain diet-related diseases in Ecuador and its possible relationship with Ecuadorian consumption habits. For that, mortality rates (2001-2008) associated with five different disease groups related to dietary factors (cancer of colon, cerebrovascular diseases, cardiovascular diseases, diabetes mellitus and liver diseases) were collected, analyzed and compared to consumption patterns in Ecuador. According to results, Ecuador has a low level of cancer of colon in comparison with developed countries (e.g. Spain). The group with the highest number of deaths corresponded to cardiovascular diseases followed by cerebrovascular diseases. The mortality study per province revealed that Amazonian provinces showed few deaths in relation to other provinces in Ecuador. This could be due to different factors including fails in the disease surveillance information systems, environmental factors and consumption patterns. In this sense, further investigation on native products consumption such as “chontaduro” might help to find valuable foods contributing to healthier Ecuadorian diet. These results, though preliminary, evidence that a major effort should be made by national and international organisations to collect data on consumption patterns and nutritional aspects of the Ecuadorian population in order to better support the development of effective food security and nutrition policies.La dieta es un factor importante en el desarrollo de numerosas enfermedades. En países en vías de desarrollo como Ecuador, este aspecto no se considera como prioridad sin embargo el estudio de la incidencia de ciertas enfermedades relacionadas con la dieta podría ayudar a evaluar los hábitos alimentarios de un país desde una perspectiva de salud pública y apoyar el desarrollo de políticas y programas nacionales de nutrición. El objetivo de este trabajo es estudiar las tasas de mortalidad de ciertas enfermedades relacionadas con la dieta en Ecuador y su posible relación con los hábitos alimentarios Ecuatorianos. Para ello, las tasas de mortalidad (2001-2008) asociadas con 5 grupos de enfermedades relacionadas con la dieta (cáncer de colon, enfermedades cerebrovasculares y cardiovasculares, diabetes mellitus, y enfermedades hepáticas) fueron recopiladas, analizadas y comparadas con los patrones de consumo de Ecuador. Los resultados indicaron que Ecuador tiene un bajo nivel de cáncer de colon en comparación con países desarrollados (por ej. España). El grupo con el mayor número de muertes correspondió a enfermedades cardiovasculares seguido por enfermedades cerebrovasculares. El estudio de mortalidad por provincia reveló que las provincias de la Amazonía presentaron pocas muertes en relación con otras regiones. Esto podría deberse a múltiples factores incluyendo deficiencias en los sistemas de vigilancia epidemiológica, factores ambientales, y hábitos de consumo. En este sentido, se evidencia una necesidad de investigar con mayor profundidad alimentos nativos tales como el “chontaduro” ya que estos podrían contribuir de manera significativa al fomento de una dieta ecuatoriana más saludable. Estos resultados, aunque preliminares, evidencian que aún se deben realizar grandes esfuerzos en la recopilación de datos sobre patrones de consumo y aspectos nutricionales de la población ecuatoriana. Su existencia posibilitará el desarrollo de políticas más efectivas de seguridad alimentaria y nutrició