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

Distribución de "Festuca patula" Desf. en la Península Ibérica; ecología y tamaños poblacionales de sus poblaciones en Las Villuercas y Los Montes de Toledo (CW de España)

Population sizes and habitat types of Festuca patula Desf. are reported for Las Villuercas and Los Montes de Toledo regions (CW Spain). The distribution range of Festuca patula in the Iberian Peninsula is increased with 21 new records: one for Sierra Nevada (Granada, S Spain) and 20 for The Villuercas and Los Montes de Toledo (Cáceres, Toledo and Ciudad Real). The individuals of the latter areas grow under different environmental conditions. They live on rocky or relatively well-developed soils derived from metamorphic rocks, ranging from 300 to 900 m above sea level. They usually grow in temperate caducifolious and marcescent forests but also colonize open scrubs on rocky slopes, often bordering riparian stands. Most of the populations contain less than 100 individuals; only one population has more than 1,000. The population sizes are apparently larger on shady wooded sites with relatively well-developed soils than in rocky sites.Se presentan datos sobre el tamaño de las poblaciones y las preferencias de hábitat de Festuca patula Desf. en Las Villuercas y Los Montes de Toledo (CW de España). Se amplia la información corológica para la península con 21 localidades nuevas: una en Sierra Nevada (Granada) y el resto en Las Villuercas y Los Montes de Toledo (Cáceres, Toledo y Ciudad Real). Las poblaciones de estos dos últimos territorios habitan en distintas condiciones ambientales. Se encuentran entre los 300 y 1.000 m de altitud, instaladas en sustratos metamórficos, creciendo en el sotobosque de frondosas (quejigos, alcornoques, encinas, castaños, etc.) y en los claros de matorrales en laderas rocosas que, en numerosas ocasiones, limitan con formaciones riparias (caracterizadas por alisos, fresnos, sauces, etc.). La mayoría de las poblaciones están integradas por menos de 100 ejemplares y solamente dos alcanzan o superan los 1.000 individuos. El tamaño poblacional parece ser mayor en enclaves con suelo relativamente desarrollado, en ambientes forestales sombríos

¿Cómo afecta el deporte en el GPA de los estudiantes de la USFQ? Un análisis econométrico

There is the idea that students who practice sports professionally have lower performance than students who only perform it for hobby or do not perform, as they do not drop out of classes or they do not study at home. This has been reflected in studies of US universities . But in psychological work carried out recently, we have seen that sport has a positive effect because it has effects on the brain that help improve the productivity of people . This study tries to find a causal relationship between the GPA of students and practice the sport. The results show that athletes have an increased GPA than students who do not play sports because their productivity is improved. Also, results show that students who play sports professionally do not have lower academic achievement, so their GPA does not decrease.Existe la idea que los estudiantes que realizan deporte profesionalmente tienen un menor rendimiento que los estudiantes que solo lo realizan por hobby o que no lo realizan, ya que no dejan de estudiar en o de asistir a clases por hacer deporte. Esto se ha visto reflejado en estudios realizados en universidades de Estados Unidos. Pero en trabajos psicológicos realizados últimamente, se ha visto que el deporte afecta positivamente ya que tiene efectos en el cerebro que ayudan a mejorar la productividad de las personas. Este estudio intenta descubrir una relación causal entre el GPA de los estudiantes y la práctica del deporte. Los resultados muestran que los deportistas si tienen un mayor GPA que los estudiantes que no practican deporte debido a que se mejora su productividad. También se pudo evidenciar que los estudiantes que practican deporte profesionalmente no tienen un rendimiento académico menor, es decir que su GPA no disminuye

Trabajo de sensibilización con estudiantes, padres y docentes del Colegio José Martí, inscritos al programa Pro- niño frente al trabajo infantil y la deserción escolar. Localidad Rafael Uribe Uribe Bogotá

Psicología Comunitaria – Servicio SocialEl presente proyecto tiene como objetivo mostrar el trabajo de sensibilización que se realizó con niños, padres o acudientes inscritos al Programa Pro-niño y docentes del Colegio José Martí con el fin de generar procesos de concientización frente al trabajo infantil y la deserción escolar, utilizando diferentes técnicas de la metodología IAP como: entrevista individual, grupo de discusión, talleres, etc. Puesto que los niños, niñas y adolescentes son el futuro de nuestra sociedad y son los directamente afectados privándolos de sus derechos y el buen crecimiento y el adecuado desarrollo personal. Los resultados determinan que las causas son múltiples como: las creencias de las familias, la vulnerabilidad social que tiene la comunidad y la sociedad de consumo en la que vivimos. Por último el fortalecimiento de las conductas preventivas se realiza a través de los procesos de concientización.PregradoPsicólog

Determination of 15N stable isotope natural abundances for assessing the use of saline reclaimed water in grapefruit

We reported the results of an isotopic study aimed at evaluating the medium to long-term effects of different water qualities and deficit irrigation strategies on the ecophysiology of grapefruit in a 7-year-old plantation in SE Spain. For a better understanding of the interaction between nitrogen and salts from reclaimed water, RW, an experiment using natural abundance (δ) of 15N was conducted. This study showed that in grapefruit crop irrigated with RW leaf δ15N value increased. We concluded that: (i) causal links exist between leaf δ15N isotope and salt stress: positive correlation between values of this isotope and leaf salt content was showed; (ii) excess of nitrates provided by the reclaimed irrigation water were lost in the ecosystem through leaching, denitrification, etc., enriching the medium with δ15N and increasing δ15N values in plants. Therefore, the results of this study highlight the key role that salt content from RW can play in N uptake by plants and, hence, isotopic discrimination of leaf N. Consequently, it has been demonstrated the usefulness of isotopic discrimination measure to predict crop sustainability in the medium to long term when using water sources of different quality combined with deficit irrigation strategies

Recommendations on seismic actions on bridges

The paper describes the main features of a technical Recommendation first draft on Seismic Actions on Bridges, promoted by the Spanish Ministry of Public Works (MOPT). Although much more research is needed to clarify the seismic behaviour of the vast class of problems present in port structures the current state of the art allows at least a classificaton of subjects and the establishment of minimum requirements to guide the design. Also the use of more refined methods for specially dangerous situations needs some general guidelines that contribute to mantein the design under reasonable safety margins. The Recommendations of the Spanish MOPT are a first try in those directions

El Método de los Elementos de Contorno en termoelasticidad axisimétrica

El método de elementos de contorno se aplica con éxito a problemas en los que sea decisiva la reducción de la dimensionalidad del dominio de integración. Por ello es interesante su aplicación a cuerpos tridimensionales simétricos respecto a un eje, donde la reducción es doble y la discretización puede limitarse a un contorno monodimensional. En este artículo se presenta el método aplicado al caso de la termoelasticidad lineal. Como es bien sabido en dicho problema aparecen fuerzas de volumen que, sin embargo, pueden reducirse con cierta facilidad al contorno haciendo el método muy fructífero

The effect of boundary conditions in the numerical solution of 3-D thermoelastic problems

After the extensive research on the capabilities of the Boundary Integral Equation Method produced during the past years the versatility of its applications has been well founded. Maybe the years to come will see the in-depth analysis of several conflictive points, for example, adaptive integration, solution of the system of equations, etc. This line is clear in academic research. In this paper we comment on the incidence of the manner of imposing the boundary conditions in 3-D coupled problems. Here the effects are particularly magnified: in the first place by the simple model used (constant elements) and secondly by the process of solution, i.e. first a potential problem is solved and then the results are used as data for an elasticity problem. The errors add to both processes and small disturbances, unimportant in separated problems, can produce serious errors in the final results. The specific problem we have chosen is especially interesting. Although more general cases (i.e. transient)can be treated, here the domain integrals can be converted into boundary ones and the influence of the manner in which boundary conditions are applied will reflect the whole importance of the problem

La memoria colectiva y el pasado reciente en el cine y la televisión. Experiencias en torno a la constitución de una nueva memoria audiovisual sobre la Guerra Civil

Los autores analizan el cine y la televisión no tan sólo como herramientas configuradoras de la memória colectiva. El artículo presenta una selección comentada de los principales títulos cinematográficos y documentales sobre la guerra civil española.Els autors analitzen el cine i la televisió com a eines no només de difusió de la història sinó també, i sobretot, com a eines configuradores de la memòria col·lectiva. L'article presenta una selecció comentada dels principals títols cinematogràfics i documentals entorn la guerra civil española.The article analise cinema and television like a tool to construct commun memory. The article offers a selection of Spanish civil war' cinema and television titles

Middle Miocene (Serravallian) rhodoliths and coralline algal debris in carbonate ramps (Betic Cordillera, S Spain)

Serravallian (middle Miocene) coralline algal assemblages at the southern margin of the Guadalquivir Basin (southern Spain) occur as rhodoliths preserved in situ or very close to their growth habitats (autochthonous–parautochthonous assemblages) and also as reworked remains (allochthonous assemblages). The former assemblages consist of spherical rhodoliths built up by encrusting to warty plants and also of large fragments of branches, whereas the latter are mostly unrecognizable small fragments occurring in channeled packstone–grainstone beds. In both cases, the most abundant components are members of the order Hapalidiales (Mesophyllum roveretoi, Mesophyllum sp., Lithothamnion ramosissimum, and less frequently Phymatolithon group calcareum and Lithothamnion group corallioides). Laminar growths of Lithoporella minus and branches of Spongites group fruticulosus and Sporolithon sp. occur very rarely. There are also anecdotal records of Subterraniphyllum thomasii, extending its upper stratigraphic range up to the Serravallian in the western Tethys. The autochthonous–parautochthonous coralline algal assemblages formed in a middle ramp, at several tens of meters of water depth, as suggested by the dominance of Hapalidiales. The allochthonous assemblages represent fragments of coralline algae derived from the middle ramp and redeposited in deeper settings, most likely the outer ramp, due to storm-generated currents.Instituto de Salud Carlos III Spanish Government PGC2018-099391-B-100Junta de Andalucia RNM-19