14,963 research outputs found
A simplified hydrokinetic model for a steady‐state microwave discharge sustained by traveling waves at atmospheric pressure conditions
The properties of a microwave‐induced argon plasma produced by traveling surface wave at atmospheric pressure are investigated theoretically. A hydrokinetic model is elaborated to obtain the nonequilibrium one‐dimensional profiles of electron temperature Te (average electron energy), electron density ne, and the first excited state population density n4s, along the axis of a steady‐state discharge. A three‐level atomic structure is assumed for the argon atom. A particle balance is included through the continuity equations for ne and n4s. These equations are coupled with an energy balance equation for the electrons. The effects of different parameters on the properties of the argon discharge are investigated: discharge tube radius, gas flow rate, resonant radiation‐escape factor, and neutral gas temperature.Ministerio de Educación y Ciencia. Gobierno de España-PB91- 0847 y PB94-145
Durkheim y Saint-Simon : la construcción del ideario de la sociedad del trabajo y las nuevas paradojas de las sociedades tardo-modernas
El presente artículo tiene como principal objetivo interrogarse sobre el sentido que poseen las actuales representaciones del trabajo en el contexto del escenario productivo de las sociedades de mercado tardo-modernas. El análisis que aquí se propone interpreta dichas representaciones en relación con la obra de Émile Durkheim y Claude Henri de Saint-Simon, por ser dos de los principales autores que más han contribuido a forjar el ideario de las sociedades del trabajo, como un intento de actualización de la estructura simbólica de estas sociedades, con el fin de que continúe manteniendo toda su carga integradora y legitimadora en relación con las nuevas realidades productivas y laborales.The present article must like main objective interrogate itself on the sense that has the present representations of the work in the context of the productive scene of the take-modern societies of market. The analysis that sets out here interprets these representations in relation to the work of Émile Durkheim and Saint-Simon, being two of the main authors who have more contributed to forge the ideological formation of the societies of the work, like an attempt of update of the symbolic structure of these societies, in order that it continues maintaining all its integrating and legitimate load in relation to the new productive and labour realities
OC-OT-LIBS: A novel approach to the chemical characterization of single particles
Spectral identification of individual micro- and nano-sized particles by the sequential intervention of optical catapulting, optical trapping and laser-induced breakdown spectroscopy is presented [1]. The three techniques are used for different purposes. Optical catapulting (OC) serves to put the particulate material under inspection in aerosol form [2-4]. Optical trapping (OT) permits the isolation and manipulation of individual particles from the aerosol, which are subsequently analyzed by laser-induced breakdown spectroscopy (LIBS). Once catapulted, the dynamics of particle trapping depends on the laser beam characteristics (power and intensity gradient) and on the particle properties (size, mass and shape). Particles are stably trapped in air at atmospheric pressure and can be conveniently manipulated for a precise positioning for LIBS analysis. The spectra acquired from the individually trapped particles permit a straightforward identification of the inspected material.
The current work focuses on the development of a procedure for simultaneously acquiring dual information about the particle under study via LIBS and time-resolved plasma images by taking advantage of the aforementioned features of the OC-OT-LIBS instrument to align the multiple lines in a simple yet highly accurate way. The plasma imaging does not only further reinforce the spectral data, but also allows a better comprehension of the chemical and physical processes involved during laser-particle interaction. Also, a thorough determination of the optimal excitation conditions generating the most information out of each laser event was run along the determination of parameters such as the width of the optical trap, its stability as a function of the laser power and the laser wavelength. The extreme sensibility of the presented OC-OT-LIBS technology allows a detection power of attograms for single/individual particle analysis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
The probability of default in internal ratings based (IRB) models in Basel II: an application of the rough sets methodology
El nuevo Acuerdo de Capital de junio de 2004 (Basilea II) da cabida e incentiva la
implantación de modelos propios para la medición de los riesgos financieros en las
entidades de crédito. En el trabajo que presentamos nos centramos en los modelos internos
para la valoración del riesgo de crédito (IRB) y concretamente en la aproximación a uno de
sus componentes: la probabilidad de impago (PD).
Los métodos tradicionales usados para la modelización del riesgo de crédito, como son el
análisis discriminante y los modelos logit y probit, parten de una serie de restricciones
estadísticas. La metodología rough sets se presenta como una alternativa a los métodos
estadísticos clásicos, salvando las limitaciones de estos.
En nuestro trabajo aplicamos la metodología rought sets a una base de datos, compuesta
por 106 empresas, solicitantes de créditos, con el objeto de obtener aquellos ratios que
mejor discriminan entre empresas sanas y fallidas, así como una serie de reglas de decisión
que ayudarán a detectar las operaciones potencialmente fallidas, como primer paso en la
modelización de la probabilidad de impago. Por último, enfrentamos los resultados obtenidos
con los alcanzados con el análisis discriminante clásico, para concluir que la metodología de
los rough sets presenta mejores resultados de clasificación, en nuestro caso.The new Capital Accord of June 2004 (Basel II) opens the way for and encourages credit entities to implement
their own models for measuring financial risks. In the paper presented, we focus on the use of internal rating
based (IRB) models for the assessment of credit risk and specifically on the approach to one of their
components: probability of default (PD).
In our study we apply the rough sets methodology to a database composed of 106 companies, applicants for
credit, with the object of obtaining those ratios that discriminate best between healthy and bankrupt companies,
together with a series of decision rules that will help to detect the operations potentially in default, as a first step
in modelling the probability of default. Lastly, we compare the results obtained against those obtained using
classic discriminant análisis. We conclude that the rough sets methodology presents better risk classification
results.Junta de Andalucía P06-SEJ-0153
An advanced symbolic analyzer for the automatic generation of analog circuit design equations
A tool for symbolic analysis of analog integrated circuits is presented featuring accurate simplification, pole/zero extraction, and tools for parametric AC circuit characterization. The program, called ASAP, uses signal flowgraph methods and has been written in C for portability. In its current version, ASAP is able to deal with the complexity levels arising in typical analog building blocks when described by device-level models. The ASAP inputs and outputs, the architecture, and the graphical interface are discussed
Chemical Fingerprints in an Underwater Archaeological Shipwreck using a Remote Laser-Induced Breakdown Spectroscopy System
Nowadays, one of the most important areas of interest in archeology is the characterization of
the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to
storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged
materials is an extremely valuable source of information on the origin and precedence of the
wrecks, and also the raw materials employed during the manufacturing of the objects found in
these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative.
The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography [1]. Advantages such as rapid and in situ analysis with no sample preparation
make LIBS a suitable alternative for field measurements. A fiber-optics-based remote
instrument has been designed for the recognition and identification of artworks in underwater
archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multipulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an
improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variefy of samples to be analyzed (i.e., rocks, marble, ceramics and concrete).
In this work, parametric studies in the laboratory such as gas flow pressure, beam focal
conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remole LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Libs in cultural heritage: recognition and identification of objects in an underwater archaeological shipwreck
Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Nevertheless, sometimes it is not possible to extract the archaeological material from the marine environment due to size of the sample, the legislation or preservation purposes. In these cases, the in-situ analysis turns into the only alternative for obtaining information. In spite of this demand, no analytical techniques are available for the in-situ chemical characterization of underwater materials.
The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. To further exploit the inherent advantages of the technology, a mobile fiber-based LIBS platform capable of performing remote measurements up to 50 meters range has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS) 2. The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In the present work, the design and construction considerations of the instrument are reported and its performance is discussed on the basis of the spectral response, the remote irradiance achieved upon the range of analysis and its influence on plasma properties, as well as the effect of the laser pulse duration and purge gas to the LIBS signal. Also, to check the reliability and reproducibility of the instrument for field analysis several robustness tests were performed outside the lab. Finally, the capability of this instrument was successfully demonstrated in an underwater archaeological shipwreck (San Pedro de Alcántara, Malaga).Universidad de Málaga. Campus de Excelencia Internacional Andalucí
Remote Laser-Induced Breakdown Spectroscopy in Underwater Archaeology: Identification of Chemical Fingerprints in Shipwrecks
Nowadays, one of the most important areas of interest in archeology is the characterization of the submersed cultural heritage. Mediterranean Sea is rich in archaeological findings due to storms, accidents and naval battles since prehistoric times. Chemical analysis of submerged materials is an extremely valuable source of information on the origin and precedence of the wrecks, and also the raw materials employed during the manufacturing of the objects found in these sites. Sometimes extracting the archeological material from the marine environment is not practical due to the size of the sample, or is not permitted by the legislation or preservation practices. In these cases, the in-situ analysis turns into the only alternative.
The versatility of laser-induced breakdown spectroscopy (LIBS) has been successfully tested in oceanography 1. Advantages such as rapid and in situ analysis with no sample preparation make LIBS a suitable alternative for field measurements. A fiber-optics-based remote instrument has been designed for the recognition and identification of artworks in underwater archaeological shipwrecks. The LIBS prototype featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The use of multi-pulse excitation allowed an increased laser beam energy (up to 95 mJ) transmitted through the optical fiber. This excitation mode results in an improved performance of the equipment in terms of extended range of analysis (to a depth of 50 m) and a broader variety of samples to be analyzed (i.e., rocks, marble, ceramics and concrete). In this work, parametric studies in the laboratory such as gas flow pressure, beam focal conditions and angle of incidence, among others, were performed to optimize the best conditions for field analysis. Finally, results obtained in these field trials confirmed the capability of remote LIBS for in-situ analysis of underwater archeological samples.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
El ayer, el hoy y el ay de la gestión de la Administración de Justicia en la Comunidad Autónoma de Andalucía
La Constitución Española dispuso en su artículo 149 que la Administración de Justicia (AJ) era competencia exclusiva del Estado, pero el Tribunal Constitucional distinguiendo entre Administración de Justicia, Poder Judicial (PJ), que no se puede transferir, y la administración de la Administración de Justicia, encargada de proveer de medios materiales y personales a la primera, que sí se puede transferir, conformó una AJ desconcentrada y descentralizada. La Comunidad Autónoma de Andalucía es una de las doce CCAA que tienen las competencias transferidas (RD 141 y 142) desde 1997. Puesto que hoy en día la AJ está siendo severamente cuestionada y desde numerosos sectores, tanto de los profesionales como de la ciudadanía general, abogan por un mayor gasto como vía de solución al mal funcionamiento, la presente investigación analiza si verdaderamente es esta la solución o si el problema radica fundamentalmente en que los recursos no se están utilizando con eficiencia. Aunque la incidencia de la gestión y del gasto de las CCAA en el funcionamiento de la AJ es relativa por cuanto no todo depende exclusivamente de ellas, sí es posible analizar la evolución del funcionamiento de los juzgados y tribunales en Andalucía desde 2004 y la comparación con el resto de CCAA. Para ello usamos tres grupos de indicadores: el gasto, los medios personales y la actividad jurisdiccional durante el periodo 2004-2015.
Nuestros resultados muestran que, aunque la situación en Andalucía es dispar entre las distintas jurisdicciones, podemos afirmar un mayor deterioro del funcionamiento de la AJen el TSJA frente a otros TSJ.Esto se explica por la sobrecarga de trabajo de los jueces en Andalucía, que no ha paliado el aumento de gasto realizado en el periodo (50,2%). Así, el esfuerzo ha resultado ineficaz, al no incidir en las variables más condicionantes: número de jueces y litigiosidad
El gasto en la Administración de Justicia en España entre 2004 y 2014
El presente trabajo tiene como principal objetivo poner de manifiesto la ausencia de información clara y precisa sobre el gasto que realiza la Administración de Justicia en España. Sin desmerecer los esfuerzos que, en este sentido se han llevado a cabo por el Consejo General del Poder Judicial, la situación en 2014, en cuanto a datos disponibles, no ha mejorado sustancialmente con respecto a la del año 2004. A la descentralización de las competencias en materia judicial se une la falta de una concisa definición de qué partidas deben o no incluirse como gasto. Esto constituye un serio problema a la hora de realizar análisis sobre la eficiencia y eficacia de un sector público tan importante como es el de la Justicia, cuyo funcionamiento afecta a todos los niveles sociales y económicos de un país
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