1,255 research outputs found
Fundamentos de la hermenéutica de la verosimilitud y sus implicaciones en la hermenéutica del diagnóstico clínico
La hermenéutica de la verosimilitud tiene su fundamento en la búsqueda de la máxima coherencia posible para la interpretación de los elementos de información que están contenidos en las representaciones fenoménicas que aparecen en la comprensión. Tal coherencia permanente resulta ser un camino para el conocimiento y la acción. Se analizan las posibilidades de objetivación racional de la evidencia empírica con la que el médico se enfrenta. Se demostró que la evidencia empírica no es el resultado del consenso interpretativo, pues es sólo la aplicación metódica de la hermenéutica racional, donde el contenido cognitivo implicado en toda su estructura muestra el máximo de coherencia posible. Tal es la hermenéutica de la verosimilitud
El problema de recordar un problema para resolver un problema
El trabajo que presentamos pretende, en primer lugar, ofrecer una revisión y ordenación conceptual del trabajo experimental desarrollado so- bre el proceso de recuperación de analogos en solución de problemas por analogia. También se analizaron resultados de algunos trabajos relaciona- dos indirectamente con este tema de investigación. Un segundo objetivo 10 constituyó la evaluación de un modelo sobre solución de problemas por analogia, recientemente propuesto (Holyoak y Thagard, 1989), respecto al proceso de recuperación de análogos. El análisis desarrollado puso de ma- nifiesto que los resultados experimentales se integran dentro de tres lineas básicas de investigación: a) La participación de estructuras de conociiniento general en el proceso de recuperación de análogos; b) La dificultad de re- cuperación de análogos interdominio; y c) La participación de rasgos su- perficiales en el proceso de recuperación de análogos. Por otra parte, se discuten 10s aspectos del modelo de Holyoak y Thagard que explican co- herentemente 10s resultados obtenidos, asicomo algunos aspectos que, de momento, caen fuera del espectro explicativo de este modelo. Palabras clave: Recuperación de análogos, solución de problemas por analogia, analogia
Trajectories of functioning and mental health: determinants in general population
Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Psiquiatría. Fecha de lectura: 17-10-201
Spectroscopic and dynamical properties of comet C/2018 F4, likely a true average former member of the Oort cloud
The population of comets hosted by the Oort cloud is heterogeneous. Most
studies in this area focused on highly active objects, those with small
perihelion distances or examples of objects with peculiar physical properties
and/or unusual chemical compositions. This may have produced a biased sample of
Oort cloud comets in which the most common objects may be rare, particularly
those with perihelia well beyond the orbit of the Earth. Within this context,
the known Oort cloud comets may not be representative of the full sample. Here,
we study the spectral properties in the visible region and the cometary
activity of Comet C/2018 F4 (PANSTARRS). We also explore its orbital evolution
with the aim of understanding its origin within the context of known minor
bodies moving along nearly parabolic or hyperbolic paths. We present
observations obtained with the 10.4 m Gran Telescopio Canarias (GTC), derive
the spectral class and visible slope of C/2018 F4 and characterise its level of
cometary activity. Direct N-body simulations are carried out to explore its
orbital evolution. The absolute magnitude of C/2018 F4 is Hr=13.62+/-0.04.
Assuming a pV=0.04 its diameter is D<10.4 km. The object presents a conspicuous
coma, with a level of activity comparable to those of other comets observed at
similar heliocentric distances. Comet C/2018 F4 has a visible spectrum
consistent with that of an X-type asteroid, and has a spectral slope
S'=4.0+/-1.0 %/1000\AA and no evidence of hydration. The spectrum matches those
of well-studied primitive asteroids and comets. The analysis of its dynamical
evolution prior to discovery suggests that C/2018 F4 is not of extrasolar
origin. Although the present-day heliocentric orbit of C/2018 F4 is slightly
hyperbolic, its observational properties and past orbital evolution are
consistent with those of a dynamically old comet with an origin in the Oort
cloud.Comment: 6 pages, 5 figures. In pres
Do Natural Disasters Affect Human Capital? An Assessment Based on Existing Empirical Evidence
The last few years have seen a notable increase in the number of studies investigating the causes and effects of natural disasters in many dimensions. This paper seeks to review and assess available empirical evidence on the ex-post microeconomic effects of natural disasters on the accumulation of human capital, focusing on consumption, nutrition, education and health, including mental health. Three major findings come forward from this work. First, disasters appear to bring substantial damages to human capital, including death and destruction, and produce deleterious consequences on nutrition, education, health and many income-generating processes. Furthermore, some of these detrimental effects are both large and long-lasting. Second, there is a large degree of heterogeneity in the size – but not much in the direction – of the impacts on different socioeconomic groups. Yet, an empirical regularity across natural hazards is that the poorest carry the heaviest burden of the effects of disasters across different determinants and outcomes of human capital. Finally, although the occurrence of natural hazards is mostly out of control of authorities, there still is a significant room for policy action to minimize their impacts on the accumulation of human capital. We highlight the importance of flexible safety nets as well as the double critical role of accurate and reliable information to monitor risks and vulnerabilities, and identify the impacts and responses of households once they are hit by a disaster. The paper also lays out existing knowledge gaps, particularly in regard to the need of improving our understanding of the impacts of disasters on health outcomes, the mechanisms of transmission and the persistence of the effects in the long-run.natural disasters, human capital accumulation
A Neural Network Approach for Analyzing the Illusion of Movement in Static Images
The purpose of this work is to analyze the illusion of movement that appears when seeing certain static images. This analysis is accomplished by using a biologically plausible neural network that learned (in a unsupervised manner) to identify the movement direction of shifting training patterns. Some of the biological features that characterizes this neural network are: intrinsic plasticity to adapt firing probability, metaplasticity to regulate synaptic weights and firing adaptation of simulated pyramidal networks. After analyzing the results, we hypothesize that the illusion is due to cinematographic perception mechanisms in the brain due to which each visual frame is renewed approximately each 100 msec. Blurring of moving object in visual frames might be interpreted by the brain as movement, the same as if we present a static blurred object
Telecommunications Network Planning and Maintenance
Telecommunications network operators are on a constant challenge to provide new services which require ubiquitous broadband access. In an attempt to do so, they are faced with many problems such as the network coverage or providing the guaranteed Quality of Service (QoS). Network planning is a multi-objective optimization problem which involves clustering the area of interest by minimizing a cost function which includes relevant parameters, such as installation cost, distance between user and base station, supported traffic, quality of received signal, etc. On the other hand, service assurance deals with the disorders that occur in hardware or software of the managed network. This paper presents a large number of multicriteria techniques that have been developed to deal with different kinds of problems regarding network planning and service assurance. The state of the art presented will help the reader to develop a broader understanding of the problems in the domain
Comparación de métodos para modelar la aquiescencia en escalas multidimensionales parcialmente balanceadas.
Background: The inclusion of direct and reversed items in scales is a commonly-used strategy to control acquiescence bias. However, this is not enough to avoid the distortions produced by this response style in the structure of covariances and means of the scale in question. This simulation study provides evidence on the performance of two different procedures for modelling the influence of acquiescence bias on partially balanced multidimensional scales: a method based on exploratory factor analysis (EFA) with target rotation, and a method based on random intercept factor analysis (RIFA). Method: The independent variables analyzed in a simulation study were sample size, number of items per factor, balance of substantive loadings of direct and reversed items, size and heterogeneity of acquiescence loadings, and inter-factor correlation. Results: The RIFA method had better performance over most of the conditions, especially for the balanced conditions, although the variance of acquiescence factor loadings had a certain impact. In relation to the EFA method, it was severely affected by a low degree of balance. Conclusions: RIFA seems the most robust approach, but EFA also remains a good alternative for medium and fully balanced scales.Antecedentes: la
inclusión de ítems directos e inversos en escalas es una estrategia
comúnmente utilizada para controlar el sesgo de aquiescencia. No
obstante, esto es insufi ciente para evitar las distorsiones producidas por
este estilo de respuesta en la estructura de covarianzas y medias de la
escala. El presente estudio de simulación aporta evidencia sobre el
rendimiento de dos procedimientos para controlar la infl uencia del sesgo
de aquiescencia en escalas multidimensionales parcialmente balanceadas:
un método basado en análisis factorial exploratorio con rotación target
(EFA), y un método basado en el análisis factorial confi rmatorio con
intercepto aleatorio (RIFA). Método: las variables independientes del
estudio de simulación fueron: tamaño muestral, número de ítems por
factor, balanceo de los pesos sustantivos de los ítems directos e inversos,
tamaño y heterogeneidad de los pesos en aquiescencia, y correlación
entre factores. Resultados: el método RIFA tiene mejor funcionamiento
en general, especialmente para las condiciones balanceadas, aunque la
varianza de los pesos de aquiescencia tuvo impacto en su rendimiento.
El método EFA se ve principalmente afectado en la situación de bajo
balanceo. Conclusiones: el RIFA parece la aproximación más robusta,
aunque el EFA se mantiene como una alternativa a considerar para escalas
con balanceo medio o completoThis research was partially supported by Ministerio de Ciencia,
Innovación y Universidades, Spain (Grant PSI2017-85022-P),
European Social Fund, and Cátedra de Modelos y Aplicaciones
Psicométricas (Instituto de Ingeniería del Conocimiento and
Autonomous University of Madrid)
An Empirical Study of Real-World SPARQL Queries
Understanding how users tailor their SPARQL queries is crucial when designing
query evaluation engines or fine-tuning RDF stores with performance in mind. In
this paper we analyze 3 million real-world SPARQL queries extracted from logs
of the DBPedia and SWDF public endpoints. We aim at finding which are the most
used language elements both from syntactical and structural perspectives,
paying special attention to triple patterns and joins, since they are indeed
some of the most expensive SPARQL operations at evaluation phase. We have
determined that most of the queries are simple and include few triple patterns
and joins, being Subject-Subject, Subject-Object and Object-Object the most
common join types. The graph patterns are usually star-shaped and despite
triple pattern chains exist, they are generally short.Comment: 1st International Workshop on Usage Analysis and the Web of Data
(USEWOD2011) in the 20th International World Wide Web Conference (WWW2011),
Hyderabad, India, March 28th, 201
Tratamiento de las cefaleas funcionales: consideraciones actuales y propuesta de intervención
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