Mathematical Genesis of the Spatio-Temporal Covariance Functions

Obtaining new and flexible classes of nonseparable spatio-temporal covariances have resulted in a key point of research in the last years within the context of spatiotemporal Geostatistics. Approach: In general, the literature has focused on the problem of full symmetry and the problem of anisotropy has been overcome. Results: By exploring mathematical properties of positive definite functions and their close connection to covariance functions we are able to develop new spatio-temporal covariance models taking into account the problem of spatial anisotropy. Conclusion/Recommendations: The resulting structures are proved to have certain interesting mathematical properties, together with a considerable applicability.Spatial anisotropy, bernstein and complete monotone functions, spatio-temporal geostatistics, positive definite functions, space-time modeling, spatio-temporal data

Método de estrato finito para muros de retención con cimentación flexible ante excitación sísmica

ResumenSe presenta un método de estrato finito para evaluar los efectos de la acción sísmica en muros de retención, el cual se basa en la teoría de propagación de ondas y superposición modal. El sistema está definido por un muro rígido desplantado sobre un estrato elástico, con capacidad de deslizamiento y volteo de la base. Con este modelo se considera tanto la flexibilidad de la cimentación como la disipación de energía por radiación de ondas. Se demuestra con resultados numéricos que la magnitud de las presiones sobre el muro depende de su capacidad de moverse.AbstractA finite layer method for evaluation of the effects of seismic action on retaining walls is presented, which is based on the wave propagation theory and modal superposition. The system is defined by a rigid wall supported on an elastic stratum, with capacity of sliding and overturning of the base. With this model, the foundation flexibility as well as the energy dissipation by wave radiation is considered. It is demonstrated with numerical results that the magnitude of pressures on the wall depends on its movement capacity

Compactness in Banach space theory - selected problems

We list a number of problems in several topics related to compactness in nonseparable Banach spaces. Namely, about the Hilbertian ball in its weak topology, spaces of continuous functions on Eberlein compacta, WCG Banach spaces, Valdivia compacta and Radon-Nikod\'{y}m compacta

Aves limícolas (Charadrii) en un embalse del centro de la Península Ibérica durante el ciclo anual: zonas interiores vs. zonas litorales

The structure and dynamics of wader assernblages in a reservoir in the centre of the lberian peninsula (Los Canchales, Badajoz, SW Spain) was studied over a one-year period. The comparison between these assemblages and others from inland and coastal wetlands of the peninsula is analysed. The highest number of birds in Los Canchales reservoir was registered during the migration periods. This pattern fits that observed in other inland wetlands with slow waters, but is different from the pattern observed in inland rivers, probably dueto the smaller available surface for the majority of these species. The occurrence of Vanellus vanellus in inland wetlands brings about the dominance of the Charadriidae in contrast with coastal wetlands where the Scolopacidae is the dominant family as a result of the great numbers of birds of the Calidris genus. Key words: Waders, Reservoir, Inland, Annual dynamic, Charadrii.The structure and dynamics of wader assernblages in a reservoir in the centre of the lberian peninsula (Los Canchales, Badajoz, SW Spain) was studied over a one-year period. The comparison between these assemblages and others from inland and coastal wetlands of the peninsula is analysed. The highest number of birds in Los Canchales reservoir was registered during the migration periods. This pattern fits that observed in other inland wetlands with slow waters, but is different from the pattern observed in inland rivers, probably dueto the smaller available surface for the majority of these species. The occurrence of Vanellus vanellus in inland wetlands brings about the dominance of the Charadriidae in contrast with coastal wetlands where the Scolopacidae is the dominant family as a result of the great numbers of birds of the Calidris genus. Key words: Waders, Reservoir, Inland, Annual dynamic, Charadrii.The structure and dynamics of wader assernblages in a reservoir in the centre of the lberian peninsula (Los Canchales, Badajoz, SW Spain) was studied over a one-year period. The comparison between these assemblages and others from inland and coastal wetlands of the peninsula is analysed. The highest number of birds in Los Canchales reservoir was registered during the migration periods. This pattern fits that observed in other inland wetlands with slow waters, but is different from the pattern observed in inland rivers, probably dueto the smaller available surface for the majority of these species. The occurrence of Vanellus vanellus in inland wetlands brings about the dominance of the Charadriidae in contrast with coastal wetlands where the Scolopacidae is the dominant family as a result of the great numbers of birds of the Calidris genus. Key words: Waders, Reservoir, Inland, Annual dynamic, Charadrii

Distribución, autoecología y biogeografía de los Dryopidae y Elmidae (Coleoptera, Dryopoidea) en las islas Baleares

The distribution of the Dryopidae and Elmidae in the Balearic Islands was studied. Three species of Dryopidae —Dryops algiricus (Lucas, 1949), D. gracilis (Karsch, 1881) and D. sulcipennis (Costa, 1883)— and one of Elmidae —Oulimnius echinatus Berthélemy, 1979— were found. Bibliographical data of other three species of Dryopidae exist, but their presence is either refuted —Dryops lutulentus (Erichson, 1847)— or requires confirmation —Dryops luridus (Erichson, 1847) and D. rufipes (Krynicki, 1832)—. Dryops gracilis and D. sulcipennis are recorded for first time in the archipelago. The first autecological data of the different species in the archipelago and a biogeographical analysis are provided.Se realiza un estudio sobre la distribución de los Dryopidae y Elmidae en las islas Baleares. Tres especies de Dryopidae —Dryops algiricus (Lucas, 1949), D. gracilis (Karsch, 1881) y D. sulcipennis (Costa, 1883)— y una de Elmidae —Oulimnius echinatus Berthélemy, 1979— han sido halladas. Existen datos bibliográficos de otras tres especies de Dryopidae, pero su presencia es excluida —Dryops lutulentus (Erichson, 1847)— o se considera que debe ser confirmada —Dryops luridus (Erichson, 1847) y D. rufipes (Krynicki, 1832)—. Dryops gracilis y D. sulcipennis se citan por primera vez en el archipiélago. Se aportan los primeros datos sobre la autoecología de las diferentes especies en las islas y se realiza un análisis biogeográfico

Atenuación de ondas elásticas con barreras de pilotes

Se presenta una solución analítica para resolver el problema de aislamiento de cimentaciones, de vibraciones generadas en su cercanía, mediante barreras de pilotes. El sistema de aislamiento está formado por una línea de pilotes elásticos y la exitación está dada por una fuente de ondas cilíndricas SV. El problema se formula bidimensionalmente como uno de difracción múltiple de ondas elásticas, los campos reflejados y refractados por los pilotes se construyen mediante expansiones de funciones de ondas cilíndricas. La solución exacta se obtiene al satisfacer idénticamente las condiciones de continuidad de desplazamientos y esfuerzos en las interfases suelo-pilote, con la ayuda del teorema de adición de Graf. Se presentan algunos resultados numéricos que muestran el comportamiento de barreras de pilotes como sistema de aislamiento, y se define un índice de transmisibilidad para medir su efectividad.Peer Reviewe