The Intermediate Band Solar Cell: Progress Toward the Realization of an Attractive Concept

The intermediate band (IB) solar cell has been proposed to increase the current of solar cells while at the same time preserving the output voltage in order to produce an efficiency that ideally is above the limit established by Shockley and Queisser in 1961. The concept is described and the present realizations and acquired understanding are explained. Quantum dots are used to make the cells but the efficiencies that have been achieved so far are not yet satisfactory. Possible ways to overcome the issues involved are depicted. Alternatively, and against early predictions, IB alloys have been prepared and cells that undoubtedly display the IB behavior have been fabricated, although their efficiency is still low. Full development of this concept is not trivial but it is expected that once the development of IB solar cells is fully mastered, IB solar cells should be able to operate in tandem in concentrators with very high efficiencies or as thin cells at low cost with efficiencies above the present ones

Can Impurities be Beneficial to Photovoltaics?

The state of the art of the intermediate band solar cells is presented with emphasis on the use of impurities or alloys to form bulk intermediate band materials. Quantum dot intermediate band solar cells start to present already attractive efficiencies but many difficulties jeopardize the immediate achievement of record efficiency cells. To complement this research it is worthwhile examining bulk materials presenting an IB. Four or perhaps more materials have already proven to have it and several paths for the research of more are today open but no solar cell has yet been published based on them. This topic has already attracted many researches and abundant funds for their development worldwide

"Comment on "Thermodynamics limits of quantum photovoltaic cell efficiency" [Appl. Phys. Lett. 91, 223507 (2007)]"

This article claims the photovoltaic cell efficiency calculated using the Luque and Marti model

Data reduction in the ITMS system through a data acquisition model with self-adaptive sampling rate

Long pulse or steady state operation of fusion experiments require data acquisition and processing systems that reduce the volume of data involved. The availability of self-adaptive sampling rate systems and the use of real-time lossless data compression techniques can help solve these problems. The former is important for continuous adaptation of sampling frequency for experimental requirements. The latter allows the maintenance of continuous digitization under limited memory conditions. This can be achieved by permanent transmission of compressed data to other systems. The compacted transfer ensures the use of minimum bandwidth. This paper presents an implementation based on intelligent test and measurement system (ITMS), a data acquisition system architecture with multiprocessing capabilities that permits it to adapt the system’s sampling frequency throughout the experiment. The sampling rate can be controlled depending on the experiment’s specific requirements by using an external dc voltage signal or by defining user events through software. The system takes advantage of the high processing capabilities of the ITMS platform to implement a data reduction mechanism based in lossless data compression algorithms which are themselves based in periodic deltas

La Universidad de Marañón.

En este trabajo se pretende estudiar la trayectoria de Gregorio Marañón en el mundo universitario y, especialmente, su pensamiento acerca de la Universidad de su tiempo ?pensamiento desarrollado y referido, fundamentalmente, a la Universidad durante el Primer Franquismo?. Para ello, se analiza su participación en algunos de los principales debates académicos de la época y las diferentes influencias que su pensamiento universitario recibió. Consecuencia de su análisis de las principales deficiencias de la situación universitaria española, abogó por la creación de un espíritu universitario. Marañón participó en la corriente intelectual que, tras la guerra civil, trató de recuperar la tradición liberal española que había quedado truncada con la llegada del General Franco al poder.This work endeavours to study the course taken by Gregorio Marañón in the academic world and, especially, his thoughts on the University of his time ?thoughts that, fundamentally, developed during the First Franco Years and speak to the University of that period?. It thus analyzes his participation in some of the principal academic debates of the time, as well as the various influences his thoughts about the academy received. Marañón advocated the creation of a university spirit, which sprung from his analysis of the main defíciencies suffered by the academy. Marañón participated in the intellectual movement that, tried to recover the liberal Spanish tradition that had been cut short with the coming to power of General Franco after the civil war.Publicad

Ferrajoli’s Equity and Aristotle’s Equity: A Critical Comparison

En este trabajo se hace un análisis crítico de la idea de equidad de Ferrajoli. Para discutir la concepción cognoscitivista de la jurisdicción defendida por el teórico italiano y el lugar que la equidad ocupa en ella (como «poder de connotación», junto a los poderes de «denotación», «comprobación fáctica» y «disposición») se propone una comparación crítica con la teoría clásica de la equidad de Aristóteles. Esta comparación contrasta ese modelo positivista con el modelo pragmático de las reglas y de la deliberación judicial como razonamiento práctico que se deriva de la idea aristotélica de «prudencia» y se encuentra en el trasfondo de la tesis de la epieikeia como «corrección de la ley». A partir de aquí se muestran, por un lado, las insuficiencias del planteamiento ferrajoliano de la jurisdicción basado en una idea de «verdad» deudora de la dicotomía positivista hecho-valor, argumentando que su tesis de la equidad como «connotación de lo que la ley denota» y «comprensión de las circunstancias de hecho del caso» mantiene en el fondo la misma posición del formalismo clásico ilustrado. Por otro lado, se destacan las inconsistencias que tal comprensión supone para el proyecto de constitucionalismo positivista de Ferrajoli, subrayando que la función judicial, y particularmente en el Estado constitucional, es indisociable de la idea de verdad como corrección práctica y de la coherencia como ideal metódico.The purpose of this paper is to elaborate a critical approach to Ferrajoli’s conception of equity. Its author undertakes a critical analysis on the cognitivist conception of jurisdiction to be found in the Italian author, particularly on the role played by equity thereof (as «power of connotation» coming along with the «denotation power», «fact finding power» and «ethical-political disposition power» of the judge) using for this purposes Aristotle’s classical theory on equity. In this comparison, Ferrajoli’s positivist model is confronted with Aristotle’s pragmatic model of rules and with judicial deliberation as practical reasoning, this latter derived from his notion of «prudence» underlying the concept of epieikeia as «correction of the law». It is then that the deficiencies of Ferrajoli’s approach to jurisdiction, based on a conception of the notion of truth following the positivist fact-value dichotomy, are observed. The author argues that Ferrajoli’s thesis on equity as «connotation of what is denoted by the law» and «understanding of the factual circumstances of the case» really tantamount to the classical formalist conception on jurisdiction. Moreover it is argued that holding this understanding of jurisdiction turns Ferrajoli’s positivist constitutionalism inconsistent. For the judicial function, especially in the constitutional rule-of-law state, needs to be considered as inseparable from the notion of truth as practical correction and from the methodical ideal of coherence.Este trabajo ha sido realizado en el marco del proyecto de investigación Constitucionalismo y argumentación (DER2010-21032) financiado por el Ministerio de Ciencia e Innovación

Práctica pedagógica etnocomunitaria EDAA6

La práctica pedagógica etnocomunitaria tuvo como objetivo el acompañamiento a las clases de ciencias sociales y emprendimiento en diferentes grados de la institución educativa Pedro Uribe Mejía y la ejecución del proyecto transversal Mediadores de Aula y Diversidad Cultural, con un total de 24 estudiantes de todos los grados. En el acompañamiento académico se dio un periodo de observación y adaptación con el ambiente, lo que preciso vislumbrar cómo el contexto y sus dinámicas influyen en el comportamiento e interés de los estudiantes frente al proceso educativo. Aproximarse a la realidad que viven los estudiantes, fue el primer paso para repensar en la educación que pretende transformar diferentes contextos, fue así, que se hizo necesaria desde la labor etnoeducativa, la intención de acompañar a los estudiantes en una fase de escucha y retroalimentación, para comprender el porqué de su comportamiento y generar reflexiones frente a ello. De este modo, la práctica educativa, buscó integrarse a las diferentes dinámicas de la institución educativa, los estudiantes y también a las diferentes dificultades que se evidenciaron, con el acompañamiento del practicante en el aula y su rol orientador por medio del proyecto transversal. Mediante esa integración, se posibilitó el desarrollo de metodologías alternativas para abordar los contenidos con los estudiantes, fue así que para el desarrollo de muchas clases, se tuvo en cuenta las habilidades y dificultades de cada estudiante, potencializando la labor del etnoeducador como docente, fijarse en el sujeto y generar estrategias educativas para acompañar y favorecer el aprendizaje y participación de los estudiantes

Event Recognition Using Signal Spectrograms in Long Pulse Experiments

As discharge duration increases, real-time complex analysis of the signal becomes more important. In this context, data acquisition and processing systems must provide models for designing experiments which use event oriented plasma control. One example of advanced data analysis is signal classification. The off-line statistical analysis of a large number of discharges provides information to develop algorithms for the determination of the plasma parameters from measurements of magnetohydrodinamic waves, for example, to detect density fluctuations induced by the Alfvén cascades using morphological patterns. The need to apply different algorithms to the signals and to address different processing algorithms using the previous results necessitates the use of an event-based experiment. The Intelligent Test and Measurement System platform is an example of architecture designed to implement distributed data acquisition and real-time processing systems. The processing algorithm sequence is modeled using an event-based paradigm. The adaptive capacity of this model is based on the logic defined by the use of state machines in SCXML. The Intelligent Test and Measurement System platform mixes a local multiprocessing model with a distributed deployment of services based on Jini

El síndrome anorexia caquexia

The anorexia-cachexia syndrome is a paraneoplasic, metabolic disorder characterized by the appearance of appetite decrease, loss of weight and muscular mass atrophy, which in spite of a correct caloric and nutritional contribution is not achieved to solve. This entity is frequent among patients with malignant tumors. And its result, the malnutrition, drives to a series of complications in the shape of alterations at immune system and related to the oncological treatments, attributing to these patients a worse prognosis. The fisiopathology is explained by the existence of a deregulation at hypothalamic center that has the control of the appetite consequence of the production of several cytokines. According to the irreversibility of the syndrome, once it is established, the most relevant aspect to manage it will be the preventive measurements and obviously a good psycho-emotional support from the sanitary professionals