Los mitos griegos de la creación. La Cosmología

Sin resume

Measurement of disparities between indicators associated with the welfare in Least Developed Countries (LDCs) of Asia

Medir los factores que inciden en el bienestar social de los países es una tarea compleja, especialmente cuando se trata de países pocos desarrollados. A pesar de todo, se han producido avances relevantes, aunque sigue siendo un camino por el que hay que seguir buscando procedimientos que lo enriquezcan. En este artículo, se propone una medición de las disparidades entre indicadores de bienestar social aplicados a un grupo de países muy afectados por la pobreza, los países menos adelantados (PMA), que según la terminología de la Conferencia de Naciones Unidas para el Comercio y el Desarrollo (UNCTAD) son los más pobres entre los pobres. En nuestro análisis nos referiremos a los del continente asiático. La novedad de este trabajo es que el índice propuesto se ha construido atendiendo a un número de variables más amplia que los índices de bienestar más utilizados y a los criterios definidos en los Objetivos de desarrollo de la Declaración del Milenio, entre los que existe un consenso general que son los que determinan los niveles de subdesarrollo de los países. Como técnica aplicada a los datos proporcionados por Naciones Unidas y recogidos en el Informe Anual de los PMA, se ha empleado el método de distancia P2 para el año 2007, el último para el que disponíamos de datos definitivos. Este índice integra variables socioeconómicas, que permiten una ordenación territorial de los PMA de Asia, en función de esos indicadores parciales.___________________________________________Measuring factors that affect countries’ social welfare is a complex task, especially in the case of the Least Developed Countries. Despite this difficulty, important advances have been made, though many more remain to be made in the search for procedures that will enrich these analyses. In this article we present a new proposal for the measurement of disparities between indicators of social welfare, applied to a group of countries especially affected by poverty: the Least Developed Countries (LDCs) which in the terminology of the United Nations Conference on Trade and Development (UNCTAD) are the poorest of the poor. In our analysis we will refer to the Asian continent. Our index is novel in that it has been constructed taking into account a larger number of variables than the welfare indices most usually used, and the criteria defined in the Goals of the Millennium Declaration, which are generally considered to determine countries’ levels of underdevelopment . As technique applied to the data, provided by the UN and listed in the Annual Report of the LDCs for 2007, the latest year for which definitive data were available, we have used the P2 distance method. This index integrates socio-economic variables that permit a ranking of the LDCs of Asia, in terms of those partial indicators

Prevención y lucha contra la contaminación marina

La Contaminación Marina se define como la "introducción, directa o indirecta, de sustancia o energéticos en el medio marino, la cual acaba por dañar los recursos vivos, poner en peligro la salud humana, alterar las actividades marinas, reducir el valor recreativo y la calidad del agua”. Existe una gran variación de tipos de contaminación: estas pueden ser de tipo acústica, químicas, biológicas y físicas en general. Los países han de disponer de los medios necesarios para la lucha contra la contaminación marina, utilizando las técnicas adecuadas en cada momento, y para ello se requiere de personal especializado y formado así como de las herramientas necesarias para la prevención y lucha contra la contaminación. En los últimos años han habido grandes avances en la observación y vigilancia contra la contaminación, como la vigilancia aérea o satelitaria. No debemos olvidar que la mejor prevención y lucha contra la contaminación es la información, educación y formación de sus ciudadanos

Influence of Partial Soil Wetting on Water Relation Parameters of the Olive Tree

A drip versus pond irrigation experiment was carried out with 30-year-old ‘Manzanilla’ olive trees planted at 7 m 5 m in an orchard in Southwest Spain. At the end of the dry season of 1998, we chose two dry-land trees, D1 and D2, and two drip-irrigated trees, I1 and I2. During the experiments, the D1 and I1 trees were pond-irrigated, increasing the soil water content to around field capacity in the whole rootzone. The D2 and I2 trees were drip-irrigated, remaining part of the rootzone in drying soil. The results showed that the ratio between the transpiration of the pond-irrigated D1 tree and that of the drip-irrigated D2 tree (D1/D2 Ep) increased from an average of 0.88 before irrigation to 1.22 fourteen days after the first water supply. For the I trees, I1/I2 Ep varied from 0.76 to 1.02 nine days after the I1 tree was pond-irrigated for the first time. Transpiration, therefore, was restricted when using a drip irrigation system which, despite supplying enough water to cover the calculated crop demand, affected a part of the rootzone only. During the drip versus pond irrigation experiment, the recovery of leaf water potential, stomatal conductance and photosynthesis rate was greater and quicker in the pond-irrigated than in the drip-irrigated trees.– Influence de l’irrigation partielle du sol sur les paramètres des relations hydriques de l’olivier. Une comparaison de l’irrigation goutte à goutte avec l’irrigation en cuvette a été conduite sur oliviers ‘Manzanilla’ âgés de 30 ans plantés à 7 m 5 m dans un verger du sud-ouest de l’Espagne. À la fin de la saison sèche de 1998, nous avons choisi deux arbres sur sol sec, D1 et D2, et deux arbres sur sol irrigué au goutte à goutte, I1 et I2. Durant les expériences, les arbres D1 et I1 ont été irrigués en cuvette, en augmentant la teneur en eau du sol jusqu’à la capacité au champ dans toute la zone racinaire. Les arbres D2 et I2 ont été irrigués au goutte à goutte, laissant une partie de la zone racinaire dans un sol se desséchant. Les résultats ont montré que le quotient entre la transpiration de l’arbre D1 irrigué en cuvette et celle de l’arbre D2 irrigué au goutte à goutte (D1/D2 Ep) a augmenté à partir d’une moyenne de 0,88 avant irrigation jusqu’à 1,22 quatorze jours après le premier apport d’eau. Pour les arbres I, I1/I2 Ep a varié entre 0,76 et 1,02 neuf jours après que l’arbre I1 ait été irrigué en cuvette pour la première fois. Par conséquent, la transpiration était réduite quand on utilisait un système d’irrigation au goutte à goutte qui, malgré l’apport d’eau suffisant pour couvrir les besoins potentiels des cultures, a affecté seulement une partie de la zone racinaire. Durant cette comparaison de l’irrigation goutte à goutte et de l’irrigation en cuvette, la récupération de la teneur en eau des feuilles, de la conductance stomatique et du taux de photosynthèse était supérieure et plus rapide pour les arbres irrigués en cuvette que pour ceux irrigués au goutte à goutte

Development of Magnetostrictive Transducer Prototype for Blockage Detection on Molten Salt Pipes

In solar thermal power plants molten salt is often used to store and transport the energy that is collected during the day. The external pipe temperature is measured to activate an electric heating system if the temperature approaches the melting point. However, salt solidification cannot be completely excluded from the plant management. Once occurred, the location of a salt blockage is very complex due to the high temperature of the pipe. Therefore, when this problem arises, power plants have to stop production with the consequences in time and cost that this entails. Electro-magnetic acoustic transducers can be used as non-destructive testing systems for this application. A method for salt blockage detection is proposed that is applicable in straight sections of pipes by employing torsional guided waves that are generated with magnetostrictive transducers. The present paper deals with the transducer conception and the design of the power supply to activate it. Two alternatives are proposed and compared to determine the improvement in the amplitude/noise ratio. Finally, the experimental results show the performance of the equipment in a small prototype, thus validating the technique presented

Modelo computacional para la formación de clases de equivalencia

A computational model of neuronal net closely related with the formation of equivalence classes is developed. First the formal pattern of the neuronal net is presented and then its operation and its direct relationship with the phenomenon of the formation of the equivalence classes and with the derived relationships are explained. Later on, the validation of the pattern is described carrying out several simulations allowing verification of the pattern so it is able to generate relationships not explicitly trained, these results being adjusted to the basic results of this investigation line. These simulations were carried out using a training of classic conditioning and a test phase by means of conditional discriminations

Preliminary Modelling and Implementation of the 2D-control for a Nanopositioning Long Range Stage

Different systems are recently developed to obtain effective positioning at nanometer scale with increased working ranges. For this purpose, a two-dimensional nanopositioning platform (NanoPla) has been design and manufactured. To assure the demanding metrological performance the drive and control system is being defined and validated. Based on four home-made linear motors as actuators, this work is focused on the study of the control-loop for 1D- and 2D-cases with the aim of the preliminary modelling and posterior implementation. The different required blocks are presented and an initial controller solution is proposed to achieve the established positioning requests

Level and diffusion of technology in the Andalusian industry (1980–1995)

The degree of economic development of any region is usually related to different factors. One of the most important is the technological level associated to the productive sectors. The technological level must be measured, not only by the appearance of new products and production processes (generation), but also by the possibility of including these products and processes inside the firm (adoption/diffusion). This idea means that both, generation and diffusion of technology occupy a central position in the production system of any region, and especially in some places where the SME´s are a relevant majority. One of the main targets of technological policy is the development of the technological level of the firms and by extent of the region as a whole. So it is relevant to design and study the evolution of an indicator that measures this objective. There are several ways to study the technological level of a region or of a specific economic sector. In this paper, we will follow the methodology of Input-Output Analysis that make possible a more detailed study. In this paper we are interested in investigating the relationship between the industries at the regional level of Andalusia and compared with the country as a whole. The period of analysis is 1980-1995. Our first target is to specify the input side in the innovation process by means of variables such as R&D spends, industrial employment in the R&D activities, human capital, etc., both as a whole and as share of GPD. The second step is related to the analysis of output data, characterised mainly by technological indexes (Saez, 1992) and de evolution of potentially innovative industrial sectors, which include sectors that use mainly high technological inputs and spread technology among the whole economy. The third step is concerned with study of the evolution of the Intermediate Input Requirements and Employment Requirements of every industrial sector and of the regional econom

Design optimization for the measurement accuracy improvement of a large range nanopositioning stage

Both an accurate machine design and an adequate metrology loop definition are critical factors when precision positioning represents a key issue for the final system performance. This article discusses the error budget methodology as an advantageous technique to improve the measurement accuracy of a 2D-long range stage during its design phase. The nanopositioning platform NanoPla is here presented. Its specifications, e.g., XY-travel range of 50 mm ˆ 50 mm and sub-micrometric accuracy; and some novel designed solutions, e.g., a three-layer and two-stage architecture are described. Once defined the prototype, an error analysis is performed to propose improvement design features. Then, the metrology loop of the system is mathematically modelled to define the propagation of the different sources. Several simplifications and design hypothesis are justified and validated, including the assumption of rigid body behavior, which is demonstrated after a finite element analysis verification. The different error sources and their estimated contributions are enumerated in order to conclude with the final error values obtained from the error budget. The measurement deviations obtained demonstrate the important influence of the working environmental conditions, the flatness error of the plane mirror reflectors and the accurate manufacture and assembly of the components forming the metrological loop. Thus, a temperature control of ¿0.1 ¿C results in an acceptable maximum positioning error for the developed NanoPla stage, i.e., 41 nm, 36 nm and 48 nm in X-, Y- and Z-axis, respectively

Rearrangement of the near-field landscape in heterogeneous nanoparticle arrays

Comunicación presentada en la Conferencia Española de Nanofotónica (CEN2012), celebrada en Carmona (Sevilla) del 1 al 4 de octubre de 2012.Geometric resonances in nanostructure arrays sustaining localized surface plasmons have received increasing attention in the last few years. These geometric resonances exhibit narrower peaks than the purely plasmonic ones, therefore these systems are promising candidates for sensing applications. Moreover, they provide new features in the near-field distribution patterns. Heterogeneous nanoparticle arrays offer a way to tune both the near and far-field response by using nanoparticles of different sizes, shapes or materials, but there is a lack of experimental studies in this context.Peer Reviewe