967 research outputs found
The Sackur-Tetrode equation and the measure of entropy
Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Any: 2014, Tutor: Enric PérezIs it really possible to measure absolute entropy? Motivated by this question, and
taking advantage of a previous article by W. Grimus on the Sackur-Tetrode equation (2011) [1], I
have studied the hypotheses behind this equation and the way it can be experimentally tested with
a calorimetric method. I have also analyzed data for Ne, Ar, Kr and Hg and found that they verify the ST equation, as long as the strong version of the Third Law of thermodynamics is assumed
Does student proactivity guarantee positive academic results?
This paper analyzes the impact of students’ proactivity on academic performance based on a sample from students enrolled in an introductory course of Political Economy at the University of Seville (Spain) in three consecutive courses (2014–2015, 2015–2016 and 2016–2017). Proactivity is measured by several indicators, such as class attendance, case-study oral presentation and its delivery in a foreign language, all of them being non-mandatory activities for students who have participated in the experiment. Specifically, this study aims to assess the impact of a student’s proactivity on two academic outcomes: (i) to pass or fail the exam; and (ii) the score obtained. Impact assessment has been performed using a probit and ordered multinomial logit models. The results show that a student’s proactivity measured by class attendance and case-study presentation significantly increases the probability of passing the exam, while the impact of using a foreign language seems to be non-significant. In relation to the score obtained, the proactivity measured through the case presentation raises the probability of obtaining a higher mark more than regular class attendance.Junta de Andalucía proyecto SEJ-132Universidad Autónoma de ChileUniversidad de Sevilla. Departamento de Análisis Económico y Política Económic
Elaboración de un código de buenas prácticas en comunicación aplicable a los servicios de oncología. Estrategia y resultado
Objective: To reach consensus on Codes of Best Practices, applicable to Health Care Services, to improve communication with cancer patients and their families. Methods: Evidence-based health care methodology has been used to elaborate this code. The situation in the Hospitals of the Andalusian Health Service has been analyzed, through: a) a study on professionals perspectives (difficulties, proposals of improvement and training needs) concerning communication with patients and their families; b) analysis of the quality of additional support materials; c) Patients focus groups to obtain their opinion on the communication with health professionals. Finally to elaborate the planning document, a participation and debate methodology has been followed among a wide group of professionals. Results: A code is created with 10 basic principles, that include improvement areas going from aspects that depend on health professionals to aspects related to health care organisation or the environment in which health care is given. Each principle is followed by a comment justifying its importance and recommendations that will allow its implementation. Conclusions: This code pretends to be a work tool that will allow health care deliberation on how they are carrying out this communication and will stimulate discussion between all the professionals involved, with the fi nal aim of each health care service formulating their own Communication Plan.Objetivo: Consensuar un código de buenas prácticas, aplicable a los Servicios asistenciales, para la mejora de la comunicación con los pacientes con cáncer y sus familias. Métodos: Para la elaboración de este código, se ha utilizado la metodología de atención sanitaria basada en evidencias. Se ha analizado la situación en los hospitales del Servicio Andaluz de Salud, a través de: a) la realización de un estudio sobre la perspectiva de los profesionales (dificultades, propuestas de mejora y necesidades de formación) sobre la comunicación con los pacientes y familiares; b) el análisis de la calidad del material de apoyo complementario; c) la realización de grupos de discusión con pacientes para recoger sus opiniones sobre la comunicación con los profesionales sanitarios. Finalmente para la elaboración del documento de planificación se ha seguido una metodología de participación y debate entre un amplio colectivo de profesionales. Resultados: Se elabora un código compuesto por diez principios básicos, que abarcan áreas de mejora que van desde aspectos relacionados con los profesionales sanitarios, hasta aspectos relacionados con la organización asistencial, el medio o el entorno en que se presta la atención sanitaria. Cada principio se acompaña de un comentario justificativo de su importancia y de una serie de recomendaciones que permiten su puesta en práctica. Conclusión: Este código pretende ser un instrumento de trabajo que facilite la reflexión en los Servicios asistenciales sobre cómo están realizando esa comunicación y propicie el debate entre todos los profesionales implicados, con el objetivo final de que cada Servicio elabore su propio Plan de comunicación
Fog computing pour l'intégration d'agents et de services Web dans un middleware réflexif autonome
International audienceService Oriented Architecture (SOA) has emerged as a dominant architecture for interoperability between applications, by using a weak-coupled model based on the flexibility provided by Web Services, which has led to a wide range of applications, what is known as cloud computing. On the other hand, Multi-Agent System (MAS) is widely used in the industry, because it provides an appropriate solution to complex problems, in a proactive and intelligent way. Specifically, Intelligent Environments (Smart City, Smart Classroom, Cyber Physical System, and Smart Factory, among others) obtain great benefits by using both architectures, because MAS endows intelligence to the environment, while SOA enables users to interact with cloud services, which improve the capabilities of the devices deployed in the environment. Additionally, the fog computing paradigm extends the cloud computing paradigm to be closer to the things that produce and act on the intelligent environment, allowing to deal with issues like mobility, real time, low latency, geo-localization, among other aspects. In this sense, in this article we present a middleware, which not only is capable of allowing MAS and SOA to communicate in a bidirectional and transparent way, but also, it uses the fog computing paradigm autonomously, according to the context and to the system load factor. Additionally, we analyze the performance of the incorporation of the fog-computing paradigm in our middleware and compare it with other works
A Comparison Between Kalman Filters and STDFT for Harmonic Estimation in Power Systems
5th WSEAS/IASME Int. Conf. on Electric Power Systems, High Voltages, Electric Machines, Tenerife, Spain, December 16-18, 2005This paper presents a comparison between Kalman filter and the running DFT for the computation of
harmonics in power systems applications. The performance of both filters is compared for events like voltage dips
or those in which a decaying DC component is present. The comparison considers also the presence of higher
order harmonics
Ancillary Services in Hybrid AC/DC Low Voltage Distribution Networks
In the last decade, distribution systems are experiencing a drastic transformation
with the advent of new technologies. In fact, distribution networks are no longer passive
systems, considering the current integration rates of new agents such as distributed generation,
electrical vehicles and energy storage, which are greatly influencing the way these systems are
operated. In addition, the intrinsic DC nature of these components, interfaced to the AC system
through power electronics converters, is unlocking the possibility for new distribution topologies
based on AC/DC networks. This paper analyzes the evolution of AC distribution systems,
the advantages of AC/DC hybrid arrangements and the active role that the new distributed agents
may play in the upcoming decarbonized paradigm by providing different ancillary services.Ministerio de Economía y Competitividad ENE2017-84813-RUnión Europea (Programa Horizonte 2020) 76409
Economic growth, poverty and inequality: efficiency analysis for Latin America in the 21st century
Este estudio analiza la capacidad de los modelos económicos para generar
un “eficiente” crecimiento económico que reduzca los niveles de pobreza y mejore
la distribución de la riqueza generada como resultado de ese crecimiento.
Para ello, aplicaremos un método de optimización basado en el Análisis Envolvente
de Datos a una muestra de países latinoamericanos en el que se ha
ampliado el problema de optimización con la incorporación de productos con
una connotación negativa o no deseableThis study analyzes the ability of economic models to generate “efficient”
economic growth that reduces poverty levels and improves the distribution of
wealth generated as a result of that growth. To do this, we will testly an optimization
method based on the Data Envelopment Analysis to a sample of Latin
American countries in which the problem of optimization has been extended to
the incorporation of outputs with an undesirable connotatio
Chromatographie d’exclusion: analyse de la distribution des poids moléculaires dans les silicones par GPC
En el presente trabajo se explican los fundamentos de la cromatografía de exclusión o permeación en gel (GPC) y se aplica dicha técnica a la determinación de la distribución pesos moleculares de 4 polímeros de aminodimetilsiloxano con distintos grados de polimerización y diferente contenido del grupo funcional etilendiamino. A partir de los cromatogramas GPC obtenidos y de los correspondientes datos cromatográficos, se calculan los pesos moleculares promedio (MN y MW) de las 4 siliconas analizadas y la polidispersidad de las mismas, comparándose los resultados obtenidos frente al peso molecular teóricoIn this paper, the basis of the exclusion chromatography technique or gel permeation chromatography (GPC) are exposed and this technique is applied to the molecular weight distribution analysis of 4 polymers constituted by aminodimethylpolysiloxane with different polymerization degree and ethylenediamino functional group content. Their average molecular weights (MW and MN) were calculated. From the GPC chromatograms and the corresponding chromatographic results, the polydispersity of these samples was also calculated. Results were compared with the theoretical molecular weightDans ce travail, les bases de la technique de chromatographie d’exclusion ou chromatographie de perméation en gel (GPC) sont exposées et cette technique a été appliqué à l’analyse de la distribution des poids moléculaires de 4 polymères constitués par aminodimethylpolysiloxane avec des différents degrés de polymérisation et différente teneur de groupes fonctionnels ethylenediamino.Pour les 4 polymères sélectionnés, leurs poids moléculaires moyens (MW et MN) ont été calculés. La polydispersité des échantillons a aussi été calculée à partir des correspondants chromatogrammes et de leurs données chromatographiques. Les résultats ont été comparés avec le poids moléculaire théoriquePeer Reviewe
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