El Atlas de El Escorial

Summary of the doctoral thesis «El Atlas de El Escorial» by Mr. Antonio Crespo Sanz in the department of Geography of the University of Valladolid on November 29th, 2008. Directors: Dr. Basilio Calderón Calderón (University of Valladolid) and Dr. Isabel Vicente Maroto (University of Valladolid). Board: Dr. Francisco Quirós Linares, Dr. José Luis Marcello y Barriada, Dr. Carmen Manso Porto, Dr. Gaspar Fernández Cuesta y Dr. Mariano Esteban Piñeiro.Resumen de la tesis doctoral «El Atlas de El Escorial», defendida por D. Antonio Crespo Sanz en el departamento de Geografía de la Universidad de Valladolid el 29 de noviembre de 2008. Directores: Dr. D. Basilio Calderón Calderón (Univ. de Valladolid) y Dra. Dª. Isabel Vicente Maroto (Univ. de Valladolid). Tribunal: Dr. D. Francisco Quirós Linares, Dr. D. José Luis Marcello y Barriada, Dra. Dª. Carmen Manso Porto, Dr. D. Gaspar Fernández Cuesta y Dr. D. Mariano Esteban Piñeiro

El Atlas de El Escorial

Resumen de la tesis doctoral «El Atlas de El Escorial», defendida por D. Antonio Crespo Sanz en el departamento de Geografía de la Universidad de Valladolid el 29 de noviembre de 2008. Directores: Dr. D. Basilio Calderón Calderón (Univ. de Valladolid) y Dra. Dª. Isabel Vicente Maroto (Univ. de Valladolid). Tribunal: Dr. D. Francisco Quirós Linares, Dr. D. José Luis Marcello y Barriada, Dra. Dª. Carmen Manso Porto, Dr. D. Gaspar Fernández Cuesta y Dr. D. Mariano Esteban Piñeiro

A framework for effective management of condition based maintenance programs in the context of industrial development of E-Maintenance strategies

CBM (Condition Based Maintenance) solutions are increasingly present in industrial systems due to two main circumstances: rapid evolution, without precedents, in the capture and analysis of data and significant cost reduction of supporting technologies. CBM programs in industrial systems can become extremely complex, especially when considering the effective introduction of new capabilities provided by PHM (Prognostics and Health Management) and E-maintenance disciplines. In this scenario, any CBM solution involves the management of numerous technical aspects, that the maintenance manager needs to understand, in order to be implemented properly and effectively, according to the company’s strategy. This paper provides a comprehensive representation of the key components of a generic CBM solution, this is presented using a framework or supporting structure for an effective management of the CBM programs. The concept “symptom of failure”, its corresponding analysis techniques (introduced by ISO 13379-1 and linked with RCM/FMEA analysis), and other international standard for CBM open-software application development (for instance, ISO 13374 and OSA-CBM), are used in the paper for the development of the framework. An original template has been developed, adopting the formal structure of RCM analysis templates, to integrate the information of the PHM techniques used to capture the failure mode behaviour and to manage maintenance. Finally, a case study describes the framework using the referred template.Gobierno de Andalucía P11-TEP-7303 M

CFD modelling of the interaction between the Surface Boundary Layer and rotor wake. Comparison of results obtained with different turbulence models and mesh strategies

A simplified CFD wake model based on the actuator disk concept is used to simulate the wind turbine, represented by a disk upon which a distribution of forces, defined as axial momentum sources, are applied on the incoming non-uniform flow. The rotor is supposed to be uniformly loaded, with the exerted forces function of the incident wind speed, the thrust coefficient and the rotor diameter. The model is tested under different parameterizations of turbulence models and validated through experimental measurements downwind of a wind turbine in terms of wind speed deficit and turbulence intensity

Validation of a CFD wake model based on the actuator disk technique and the thrust coefficient. Preliminary results

A simplified CFD wake model based on the actuator-disk concept is used to simulate the wind turbine, represented by an actuator disk upon which a distribution of forces, defined as axial momentum sources, are applied on the incoming flow. The rotor is supposed to be uniformly loaded, with the exerted forces as a function of the incident wind speed, the thrust coefficient and the rotor diameter. The model is validated through experimental measurements downwind of a wind turbine in terms of wind speed deficit. Validation on turbulence intensity will also be made in the near future

¿Cartografía antigua o Cartografía histórica?

Los términos relacionados con la Historia de la Cartografía necesitan ser revisados, a tenor de las confusiones y ambigüedades que se vienen produciendo. Muchas publicaciones o catálogos de mapas utilizan el término cartografía histórica para definir su contenido, cuando debería utilizarse la expresión cartografía antigua, y la traducción literal de algunas expresiones tomadas de otros idiomas, arroja resultados poco afortunados. Las nuevas tecnologías han provocado un desarrollo y una difusión inusitados de la Cartografía, y su empuje afecta a la cartografía antigua. Los principales archivos y bibliotecas publican sus fondos con gran resolución y sus documentos pueden ser analizados con herramientas más ágiles y amigables, pero no abundan los estudios teóricos sobre su naturaleza u objetivos, ni existen propuestas para reformular las definiciones básicas vinculadas a la Historia de la Cartografía. Desde estas líneas se pretende analizar y debatir el vocabulario que afecta a esta disciplina, facilitando la tarea de aquellos que se acercan a los mapas antiguos

Theoretical investigation of the lattice thermal conductivities of II-IV-V2 pnictide semiconductors

Ternary pnictides semiconductors with II-IV-V2 stoichiometry hold potential as cost effective thermoelectric materials with suitable electronic transport properties, but their lattice thermal conductivities ($\kappa$) are typically too high. Gaining insight into their vibrational properties is therefore crucial to finding strategies to reduce $\kappa$ and achieve improved thermoelectric performance. We present a theoretical exploration of the lattice thermal conductivities for a set of pnictide semiconductors with ABX2 composition (A = Zn, Cd; B = Si, Ge, Sn; and X = P, As), using machine-learning based regression algorithms to extract force constants from a reduced number of density functional theory simulations, and then solving the Boltzmann transport equation for phonons. Our results align well available experimental data, decreasing the mean absolute error by ~3 Wm-1K-1 with respect to the best previous set of theoretical predictions. Zn-based ternary pnictides have, on average, more than double the thermal conductivity of the Cd-based compounds. Anisotropic behaviour increases with the mass difference between A and B cations, but while the nature of the anion does not affect the structural anisotropy, the thermal conductivity anisotropy is typically higher for arsenides than for phosphides. We identify compounds, like CdGeAs2, for which nanostructuring to an affordable range of particle sizes could lead to values low enough for thermoelectric applications.Comment: 24 pages, 8 figure

Theoretical investigation of the lattice thermal conductivities of II–IV–V₂ pnictide semiconductors

Ternary pnictide semiconductors with II–IV–V2 stoichiometry hold potential as cost-effective thermoelectric materials with suitable electronic transport properties, but their lattice thermal conductivities (κ) are typically too high. Insights into their vibrational properties are therefore crucial to finding strategies to reduce κ and achieve improved thermoelectric performance. We present a theoretical exploration of the lattice thermal conductivities for a set of pnictide semiconductors with ABX2 composition (A = Zn, Cd; B = Si, Ge, Sn; and X = P, As) using machine-learning-based regression algorithms to extract force constants from a reduced number of density functional theory simulations and then solving the Boltzmann transport equation for phonons. Our results align well with available experimental data, decreasing the mean absolute error by ∼3 W m–1 K–1 with respect to the best previous set of theoretical predictions. Zn-based ternary pnictides have, on average, more than double the thermal conductivity of the Cd-based compounds. Anisotropic behavior increases with the mass difference between A and B cations, but while the nature of the anion does not affect the structural anisotropy, the thermal conductivity anisotropy is typically higher for arsenides than for phosphides. We identify compounds such as CdGeAs2, for which nanostructuring to an affordable range of particle sizes could lead to κ values low enough for thermoelectric applications

Caracterización de nuevos absorbentes acústicos constituidos por vermiculita

[EN] This paper wants to report an investigation of a new kind of porous absorber. Vermiculite is an ultra-lightweight material that provides excellent thermal and acoustical properties. These materials are structurally robust and easy to integrate in buildings and highway structures to control the levels of environmental noise and improve the acoustic quality of spaces. Acoustic properties, sound absorption coefficient at normal incidence and acoustic impedance, from different samples have been measured using standard UNE EN ISO 10534-2:2002.[ES] La vermiculita es un material ultraligero que presenta muy buenas propiedades térmicas y acústicas que la hacen susceptible de ser utilizada en el ámbito de la acústica de la edificación. En el presente trabajo se muestran los resultados obtenidos al caracterizar acústicamente absorbentes acústicos constituidos por vermiculita granular con diferentes granulometrías y con distintos aglutinantes mediante el tubo de impedancia.Maderuelo-Sanz, R.; Nadal Gisbert, AV.; Martín Castizo, M.; Crespo Amorós, JE.; Parres, F. (2011). Caracterización de nuevos absorbentes acústicos constituidos por vermiculita. Sociedad Española de Acústica (SEA). http://hdl.handle.net/10251/58378

Harnessing the unusually strong improvement of thermoelectric performance of AgInTe2 with nanostructuring

Nanostructuring is a well-established approach to improve the thermoelectric behavior of materials.However, its effectiveness is restricted if excessively small particle sizes are necessary to considerably decrease the lattice thermal conductivity. Furthermore, if the electrical conductivity is unfavorably affected by the nanostructuring, it could cancel out the advantages of this approach. Computer simulations predict that silver indium telluride, AgInTe2, is unique among chalcopyrite structured chalcogenides in requiring only a mild reduction of particle size to achieve a substantial reduction in lattice thermal conductivity. Here, ab-initio calculations and machine learning are combined to systematically chart the thermoelectric properties of nanostructured AgInTe2, in comparison with its Cu-based counterpart, CuInTe2. In addition to temperature and doping carrier concentration dependence, ZT is calculated for both materials as functions of the polycrystalline average grain size, taking into account the effect of nanostructuring on both phonon and electron transport. It is shown that the different order of magnitude between the mean free path of electrons and phonons disentangles the connection between the power factor and lattice thermal conductivity when reducing the crystal size. ZT values up to 2 are predicted for p-type AgInTe2 at 700 K when the average grain size is in the affordable 10-100 nm range