DSP based platform for an enhanced HF channel simulator

With the aim of improving existing tools for testing new HF transmission systems, this article describes a modification of the basic Watterson (1970) model which can be implemented without any extra added complexity with a general purpose DSP card running an a PC IBM compatible.Peer ReviewedPostprint (published version

Metamorphosis of the Modern: the Greco in the Poetry between Ages

El presente artículo analiza la presencia del Greco en la literatura hispánica de entresiglos y, más concretamente, en la poesía modernista. Su aportación más característica es el poema breve que realiza una écfrasis de un retrato del Greco, siguiendo, con mayor o menor fidelidad la manera parnasiana. El óleo casi siempre representado es El caballero de la mano al pecho. En segundo lugar, otro tipo de poema es el que trata de sugerir el misterio de la ciudad de Toledo, donde El Greco aparece como ingrediente indispensable. Otras apariciones del pintor son su empleo comparativo o su consideración como elemento decadente y grotesco, característico de una “España negra”.This paper analyses the presence of El Greco in Hispanic literature at the turn of the century and, in particular, in the modernist poetry. Its most distinctive contribution is a type of short poem that makes an ekphrasis of a portrait by El Greco and follows, more or less accurately, the Parnassian manner. The most represented painting is El caballero de la mano al pecho. Secondly, other poems try to suggest the mystery of the city of Toledo, where El Greco appears as an essential element. Other appearances of the painter include being used as a comparative or its conception as a decadent and grotesque characteristic of “la España negra”

Growth, Poverty and Employment in Brazil, Chile and Mexico

Insufficient labour income and limited access to employment are critical problems that policy makers must address when designing development strategies in Latin American countries. The persistence of the high incidence of poverty and inequality can be explained largely by the poor performance of labour markets. This Working Paper uses household survey data for Chile, Brazil and Mexico, from the early 1990s to the early 2000s, to examine the link between the growth of labour income, employment creation and the distributional impact of these factors. Through a simple decomposition of the sources of household labour income into earnings per worker and employment per population, the paper evaluates the role of economic, social and demographic factors in contributing to income changes. This decomposition shows that earnings per worker were the single most important determinant of the change in household labour income per capita. The change in earnings had the largest impact on household labour income in five of the eight country periods considered. Changes in the employment to population rate did play a role in determining labour income, but was much less important. Further decompositions show that despite favourable declines in dependency rates, the unfavourable trends of an almost ubiquitous rise of unemployment rates and, at times, the decline of participation rates dampened the contribution of employment to household labour income. The paper also decomposes labour income per capita into 20 equally sized partitions in order to evaluate its distributional pattern. A simple evaluation rule is used to validate whether changes can be considered pro-poor. Of the eight country periods analysed, only three exhibited income changes favouring the poor: Brazil in 1996-2004, Mexico in 1994-1996 and Mexico in 2000-2004. But in two of these, the pro-poor change occurred during economic contractions. In the remaining five country cases, the increase of labour income was associated with a distributional pattern that did not favour the poor. Thus, there was only one period in which labour income not only increased but was also pro-poor. But even in this case, the distribution did not favour the extremely poor. The alternating pattern of change in favour of and against the poor is explained mostly by the change in their earnings. The pattern of change in employment rarely favoured them. But when it did, usually during economic downturns, the rising participation rate of poor workers was the main reason.Earnings, Employment, Labour Markets, Pro-Poor Growth

Changes in Earnings in Brazil, Chile, and Mexico: Disentangling the Forces Behind Pro-Poor Change in Labour Markets

Despite the recovery of economic growth in Latin America during the 1990s, rising unemployment, high informality rates and sluggish wages lie at the root of high inequality and poverty. This paper looks at changes in hourly earnings from the early 1990s to the early 2000s in three relatively stable countries: Brazil, Chile and Mexico. Using econometric techniques, the paper decomposes the change in earnings per worker into changes in the demographic and socio-occupational characteristics of workers, changes in the returns to such characteristics, and changes in unobservable factors. The paper attempts to address the link between labour markets and the dynamics of inequality and poverty by comparing the average performance of the entire working labour force with the performance of the 20 per cent of workers with the lowest earnings. The paper finds that earnings per worker are the result of slow-moving changes in the structure of employment and the characteristics of workers, as well as rapid changes in the prices of labour for specific workers. Demographic changes, better education and the decline of agricultural labour are among the most significant changes in the structure of employment, and they contribute to observed changes in earnings. Among the most important changes in prices contributing to the change in earnings are changes in the returns to formal and informal employees relative to the self-employed; changes to full-time employment relative to part-time workers; changes in the returns to urban workers relative to rural workers; and change in the earnings of workers in services relative to workers in agriculture. In general, changes in earnings frequently favoured low-earning workers, mostly because of the change in the returns for their labour. This is in contrast to the changes in the structure of employment, which tended to favour high-earning workers.Changes in Earnings in Brazil, Chile, and Mexico: Disentangling the Forces Behind Pro-Poor Change in Labour Markets

Un programa de ordenador para el cálculo de las características dinámicas en puentes de doble vía

En la actual norma ministerial para la determinación de las acciones en puentes de ferrocarril se presta una gran importancia a la fijación de las características dinámicas de la estructura, a partir de las cuales se determina el coeficiente de impacto. Entre los casos peor estudiados se encuentra el de los puentes de vía doble, para los que se recomiennda una frecuencia de cálculo igual a la de un puente de la misma luz y vía simple. En el artículo se pretende analizar esta norma mediante el estudio de las frecuencias de vibración del sistema

Structural aspects of the non-uniformly continuous functions and the unbounded functions within C(X)

We prove in this paper that if a metric space supports a real continuous function which is not uniformly continuous then, under appropriate mild assumptions, there exists in fact a plethora of such functions, in both topological and algebraical senses. Corresponding results are also obtained concerning unbounded continuous functions on a non-compact metrizable space.Plan Andaluz de Investigación (Junta de Andalucía)Ministerio de Economía y Competitividad (MINECO). Españ

Development and Psychometric Properties of the Questionnaire for Assessing Educational Podcasts (QAEP).

The aim of this research was to develop and validate the Questionnaire for Assessing Educational Podcasts (QAEP), an instrument designed to gather students’ views about four dimensions of educational podcasts: access and use, design and structure, content adequacy, and value as an aid to learning. In study 1 we gathered validity evidence based on test content by asking a panel of experts to rate the clarity and relevance of items. Study 2 examined the psychometric properties of the QAEP, including confirmatory factor analysis with cross-validation to test the factor structure of the questionnaire, as well as item and reliability analysis. The results from study 1 showed that the experts considered the items to be clearly worded and relevant in terms of their content. The results from study 2 showed a factor structure consistent with the underlying dimensions, as well as configural and metric invariance across groups. The item analysis and internal consistency for scores on each factor and for total scores were also satisfactory. The scores obtained on the QAEP provide teachers with direct student feedback and highlight those aspects that need to be enhanced in order to improve the teaching/learning process.The research reported in this paper was supported by a Teaching Innovation Project (PIE17-012), funded by the University of Malaga