Vanishing Abelian integrals on zero-dimensional cycles

In this paper we study conditions for the vanishing of Abelian integrals on families of zero-dimensional cycles. That is, for any rational function $f(z)$, characterize all rational functions $g(z)$ and zero-sum integers $\{n_i\}$ such that the function $t\mapsto\sum n_ig(z_i(t))$ vanishes identically. Here $z_i(t)$ are continuously depending roots of $f(z)-t$. We introduce a notion of (un)balanced cycles. Our main result is an inductive solution of the problem of vanishing of Abelian integrals when $f,g$ are polynomials on a family of zero-dimensional cycles under the assumption that the family of cycles we consider is unbalanced as well as all the cycles encountered in the inductive process. We also solve the problem on some balanced cycles. The main motivation for our study is the problem of vanishing of Abelian integrals on single families of one-dimensional cycles. We show that our problem and our main result are sufficiently rich to include some related problems, as hyper-elliptic integrals on one-cycles, some applications to slow-fast planar systems, and the polynomial (and trigonometric) moment problem for Abel equation. This last problem was recently solved by Pakovich and Muzychuk (\cite{PM} and \cite{P}). Our approach is largely inspired by their work, thought we provide examples of vanishing Abelian integrals on zero-cycles which are not given as a sum of composition terms contrary to the situation in the solution of the polynomial moment problem.Comment: 35 pages, 1 figure; one reference added; abstract, introduction and structure change

Creatina y entrenamiento interválico de alta intensidad = Creatine and hiits

El propósito del estudio fue determinar el efecto de la suplementación con Creatina (Cr) en el entrenamiento interválico de alta intensidad y definir los posibles beneficios generados de dicha práctica. Método: Se seleccionaron 12 sujetos, los cuales fueron divididos en dos grupos: Un grupo control (n=6) y un grupo experimental (n=6, Cr 20gr/día una semana y Cr 5gr/día tres semanas), todos los sujetos realizaron entrenamiento HIIT en pista dos veces por semana. Se les tomo mediciones del lactato sanguíneo en tres fases, una cada cuatro semanas al finalizar los entrenamientos. Fueron realizados test de condición física y análisis de la composición corporal al inicio y el final del estudio. Resultados: Los resultados mostraron que la suplementación con Cr tiene efectos significativos sobre los valores de lactato sanguíneo post-ejercicio. Sin embargo no existieron resultados significativos sobre la potencia y capacidad anaeróbica. El VO2máx aumentó un 5% y el porcentaje de Masa Grasa Corporal se redujo en un 8-12% no existiendo diferencias significativas entre ambos grupos. La Masa Libre de Grasa (Kg) se mantuvo estable. Conclusión: El HIIT aumenta el VO2máx, ayuda a perder Masa Grasa Corporal (Kg) y mantener la Masa Libre de Grasa (kg). La suplementación con Cr ejerce efectos beneficiosos en actividades de alta intensidad y corta duració

Legal guarantees for the tourist in the Spanish Private Law. Improvement proposals

El trabajo que se remite versa respecto a uno de los múltiples enfoques concurrentes en el fenómeno turístico, el jurídico. Concretamente, se analiza desde la perspectiva del Derecho Privado, en cuanto elemento integrante del llamado Derecho del Turismo, el conjunto de garantías que el Ordenamiento español ofrece al turista que se ve afectado por un incumplimiento o cumplimiento defectuoso de las obligaciones y derechos que surgen de una relación jurídica trabada en ese ámbito. Sin esos remedios, la experiencia del turista resulta doblemente negativa, lo cual además de su afectación particular redunda en perjuicio del Sistema turístico y de la propia Economía nacional. Así es, no sólo quedaría mal ejecutada la relación jurídica concreta sino que no se repararía con plenitud y agilidad ese perjuicio por los mecanismos que al efecto deberían existir. Se estudian, debidamente clasificados, la conciliación, la mediación, el arbitraje y la Jurisdicción. En primer término, se repasan sus caracteres generales y, posteriormente, se proyectan hacia el concreto ámbito que constituye el turismo. La conclusión que se alcanza tras ese análisis detecta deficiencias en esos instrumentos que forzosamente hay que superar, por sus desajustes al obviar las particularidades de este ramo de actividad económica.With this work we refer to one of the competing approaches in the tourist phenomenon, the legal. Specifically, it is analysed from the perspective of Private Law, part of the so- called tourism Law, the set of guarantees that the Spanish system offers to a tourist affected by a failure or defective performance of the obligations and rights arising out of a legal relationship locked in that area. Without those remedies, the tourist experience could be doubly negative, which in addition to its particular result and fewer of the tourism system and the national Economy. So it is, not only the legal relationship affected would be poorly executed, that prejudice would be not restore with fullness and agility by mechanisms that effect should exist. We study, duly classified, conciliation, mediation, arbitration and Jurisdiction. Firstly, we review their general characters, and then we will project them to the particular of tourism. The conclusion reached after this analysis detects deficiencies in these instruments ignoring the particularities of this branch of economic activity

Tutoriales multimedia para sistemas de telecomunicación

Este Proyecto Fin de Carrera está destinado a la ilustración y aprendizaje del uso de varios dispositivos de los laboratorios del Departamento de Ingeniería Audiovisual y Comunicaciones, de la Escuela Universitaria de Ingeniería Técnica de Telecomunicación, de la Universidad Politécnica de Madrid, en forma de vídeos tutoriales basados en mediciones y prácticas habituales de las asignaturas del departamento para que puedan ser utilizados por los alumnos de la escuela como apoyo a las explicaciones del profesor en ocasiones puntuales. En concreto se han realizado hasta seis vídeos tutoriales en los que se explica: el diseño de un circuito impreso y la creación y fabricación de éste. Por otro lado, también se ha explicado el fenómeno del ruido de fase y cómo es el proceso de su medida, como una de las muchas características de un analizador de espectros. A modo de análisis, se ha realizado otro tutorial acerca de la modulación en FM, sus características y sus aplicaciones. Por último se ha hecho un estudio del comportamiento de un analizador de redes, exponiendo su funcionamiento y explicando su proceso de calibración. Para la realización de estos tutoriales se han utilizado diferentes aplicaciones sobre creación de vídeos multimedia, animación, producción de audio y narración. En especial se han usado: Sprint-Layout 5.0, Adobe Flash Professional CS5.5, Camtasia studio 7, Corel VideoStudio Pro X4, Loquendo TTS7 y WinPlot. Para el apartado de las grabaciones de las diferentes escenas se ha necesitado el uso de distintos instrumentos de medida del laboratorio tales como: analizador de espectros, analizador de redes, generador de señal, generador de funciones, osciloscopio y otros equipos adicionales como: cámara de vídeo y trípode del departamento. Para la composición de los diferentes tutoriales se ha comenzado creando un guion, para cada uno de ellos, estableciendo la aparición de las imágenes, vídeos, y locución. A continuación se exponen los diferentes temas en los que se han basado estos tutoriales de laboratorio, uno a uno. ABSTRACT. This Project is destined to learn the use of several devices at the laboratory of “Ingeniería Audiovisual y Comunicaciones” Department at “Escuela Universitaria de Ingeniería técnica de Telecomunicaciones” of “Universidad Politécnica de Madrid”, on the way as tutorial videos base on the subjects from this department to be used by the college students as help of the teacher’s explanations. In this project you will find up to six tutorial videos, showing: printed circuit design, printed circuit board manufacture. You can also find an explanation about the phenomenon of phase noise and how it’s its measurement process, as one of the many features of a spectrum analyzer. Another tutorial video is based on FM modulation, its features and applications. The last tutorial explains the networks analyzer functionalities and its calibration process. To carry out these tutorials different applications have been used to create multimedia videos, animation, audio production and storytelling. Such as Sprint Layout 5.0, Camtasia 7.0, Corel VideoStudio Pro X4, Adobe Flash Professional CS5.5, Loquendo TTS7 y WinPlot. About the recording side of the different scenes, several equipment have been required at the laboratory, such as spectrums analyzer, signal generator, oscilloscope, function generator, network analyzer and other additional devices, such as: a video camera with its tripod. The composition of the different tutorials has begun creating a script, for each of them, setting the times of appearance of images, video, speech and music. After this abstract, the different topics of the tutorials are showed, one by one

Mitigating energy poverty: Potential contributions of combining PV and building thermal mass storage in low-income households

The issue of energy poverty has devastating implications for the society, and it has been aggravated in the past years due to the economic crisis and the increase of energy prices. Among the most affected are those with low incomes and living in inefficient buildings. Unfortunately, the bitter reality is that sometimes this part of the population are facing the next question: Heating, or eating? The declining prices of distributed energy technologies such as photovoltaics provides an opportunity for positive social change. Although their use does not address energy poverty directly, substantial contributions may be made. Measurements of indoor temperatures in a social housing district of southern Spain in 2017 have revealed the unbearable temperatures that the occupants have to endure, both in summer and winter. Using this district as a case study, the present work aims to evaluate the benefits of exploiting its rooftop PV potential to cover part of the electricity consumption of the district (reducing the energy bills), and use the surplus electricity to supply power for the heat pumps in the district. Optimal alternatives regarding maximum PV production, maximum self-sufficiency ratio and minimum investment costs have been found, considering as well different options when sharing the available electricity surplus to improve the thermal comfort of the occupants. As far as the authors know, no previous study has followed an approach aimed at energy poverty alleviation such as the one presented in this work. The results show that using the surplus electricity to heat or cool the whole dwellings would improve the thermal comfort of the occupants in average up to 11% in winter and 26% in summer. If all the PV generation was used or more buildings in the area were employed to install PV modules, improvements up to 33% in winter and 67% in summer could be obtained, reducing at the same time the thermal comfort differences among the dwellings of the district

Experimental analysis of the influence of drill point angle and wear on the drilling of woven CFRPs

This paper focuses on the effect of the drill geometry on the drilling of woven Carbon Fiber Reinforced Polymer composite (CFRPs). Although different geometrical effects can be considered in drilling CFRPs, the present work focuses on the influence of point angle and wear because they are the important factors influencing hole quality and machining forces. Surface quality was evaluated in terms of delamination and superficial defects. Three different point angles were tested representative of the geometries commonly used in the industry. Two wear modes were considered, being representative of the wear patterns commonly observed when drilling CFRPs: flank wear and honed cutting edge. It was found that the crossed influence of the point angle and wear were significant to the thrust force. Delamination at the hole entry and exit showed opposite trends with the change of geometry. Also, cutting parameters were checked showing the feed's dominant influence on surface damage.This work was supported by the Ministry of Economy and Competitiveness of Spain under the project DPI2011-25999Publicad

PHDC: sistemas de enfriamiento evaporativo pasivos e híbridos para edificios – software de prediseño

PHDC, es un proyecto internacional, creado con el objetivo de promover el uso de sistemas de refrigeración Pasivos e Híbridos en los edificios entre profesionales de diseño, constructores, propietarios y usuarios. En este artículo, se describen brevemente algunos de los sistemas PHDC. En el marco de este proyecto, el trabajo de investigación realizado produce dos herramientas informáticas para el mejor y máximo aprovechamiento del objetivo del proyecto, las cuales se presentan en este artículo. Las herramientas comentadas son dos: – PHDC AirFlow, en la que se implementa el “método del bucle de presiones” para el cálculo de los caudales de aire que circulan por el interior del edificio. Se analizan los elementos-sistemas-características del edificio, con objeto de integrar un sistema de climatización basado en enfriamiento evaporativo, y se le ofrece al usuario la posibilidad de modificarlos, además se destaca la capacidad de integrar captadores de viento, chimenea solar, sistema de enfriamiento evaporativo basados en medio poroso, micronizadores o pulverizadores. – Y PHDC Energy & Comfort, en la cual se simula el comportamiento térmico del edificio: cargas térmicas, consumos del sistema de refrigeración convencional y ahorro producido al integrar el sistema evaporativo elegido en la herramienta anterior.PHDC is an international project with the objective of promoting use of passive and hybrid cooling systems in buildings between design professionals, builders, owners and users. This article describes some of the systems PHDC analized. Under this project, work of the authors produces two tools for improving and optimization of the objective of project, which are presented in this article. The tools discussed are two: – PHDC AirFlow, which implements the «loop pressure method» for calculating the air flow inside the building. It discusses elements, systems and building characteristics, in order to integrate an air conditioning system based on evaporative cooling, and offers capacity to modify, also user can integrate sensors wind, solar chimney, system based evaporative cooling in porous media, micronisers or sprays. – And PHDC Energy & Comfort, which simulates thermal behavior of building: thermal loads, consumption of conventional cooling system and savings produced by integrating the evaporative system chosen in the previous tool.Unión Europea proyecto de PHDC para la promoción y la diseminación de sistemas de refrigeración pasivos e híbridos downdraught en edificio

Natural ventilation: CFD aerodynamic study about passive extractor and windcatcher

La ventilación natural se ha ganado protagonismo en los últimos tiempos como una medida de ahorro de energía para edificios. Los dos principios fundamentales de ventilación natural son el tiro natural por diferencia de temperatura, y la fuerza del viento. El artículo pretende analizar la aerodinámica de los captadores y extractores de viento mediante fluido-mecánica computacional, optimizando las geometrías de estos elementos, y dando como producto del trabajo un modelo simplificado para poder tenerlos en cuenta el cálculo aeráulico de las instalaciones de ventilación y climatización de los edificios. Concretamente, se caracteriza una base de geometrías de captación de viento, y se elabora una guía para el diseño de geometrías de extracción ofreciendo varias de ellas como producto del trabajo realizado.In recent years, natural ventilation has won popularity as an energy saving measure for buildings. There are two fundamental principles of natural ventilation: natural draft by temperature differences, and wind force. The purpose of the article is to analyze the aerodynamics of windcatchers and wind-extractors by means of computational fluid mechanics, optimizing the geometries of these elements, and giving a simplified model as a result of the work, so as to include it in the aeraulic calculation of the buildings’ air conditioning systems. Therefore, a base for wind catching geometries has been characterized, and a guide for the design of extraction geometries has been developed; several of them are offered as a result of the work undertaken

Influence of special tool geometry in drilling woven CFRPs materials

Machining processes of Carbon Fiber Reinforced Polymer (CFRP) are commonly required in order to achieve final assembly specifications. Despite the good mechanical properties of this kind of materials, they are hard to be machined due to the presence of hard particles; delamination, fiber pull-out and matrix thermal degradation are usually observed during its machining. Drilling operations are required before mechanical joining of the CFRP components. The actual interest in reducing delamination rests in the fact that it is the most serious damage found during drilling. In this work, a comparative study of three special geometries under different cutting conditions is presented. Thrust force and torque were monitoring during drilling tests and delamination extension was quantified. Results showed that a good drill tip geometry and feed rate selection is fundamental to reduce delamination damages.The funding received from the Ministry of Economy and Competitiveness of Spain under the project DPI2011-25999 and FPI subprogram with the reference BES-2012-055162 is highly appreciated