Reconocimiento geofísico del deslizamiento de Rosiana (depresión de Tirajana, Gran Canaria)

The landslide of Rosiana is considered the largest slope movement amongst those known in historical times in Gran Canana, Canary Islands. It has been activated at least 4 times in the last century, and in the movement of 1956, when about 3.106 m3 of materials were involved, 250 people had to be evacuated and many buildings were destroyed. The present geological hazard has lead to specific studies of the phenomenon which, once characterised, can be used as a guide for the scientific and technical works that are to be made in this or similar areas. This paper wants to increase the knowledge about the unstable mass of Rosiana by using geophysical techniques based on the method of seismic by refraction. The geophysical measues have been interpreted with the aid of the available geomorphologic data, thus obtaining a first approximation to the geometry of the slope movements

Aplicació de tècniques geofísiques electromagnètiques a la localització de zones afectades per abocaments incontrolats de residus

Increase of the metropolitan area of cities provoking a progressive settlement of zones that previously had a different territorial use. These zones are usually located within city houndaries and for many years have been affected hy the waste of many kinds of residues. Qualitative analysis of the electrical behaviour of soil, based on maps and cross sections of apparent conductivity, allows us to locate anomalies generated by the wastes. Moreover, the electrornagnetic techniques (EM-31 and EM-34 Geonics devices) are cheaper than other survey methods. Two examples in the campus of the University of Girona, in the southern area of Girona city, illustrate the environmental problem and the applicability of the geophysical method

Morfogènesi de pilars de terra (earth Pillars, hoodoos). Exemples de la Riera de Gaià (Vallès Occidental, Barcelona) i del Bernal de Yátor (Las Alpujarras, Granada)

The origin and the primary features of the erosive earth pillar-like formations that develop in the Riera de Gaià (Barcelona) and in the Bernal de Yátor (Granada) are described. They are dynamic formations typical of areas subjected to strong water erosion

Participació de les aigües subterrànies en la gènesi d'ambients palustres continentals: el cas dels prats de Sant Sebastià (Caldes de Malavella, Girona)

The area known as 'prats de Sant Sebastià' is in Caldes de Malavella. It is part of the wetlands located in the south-eastern end of the Selva Basin. Several areas with unusually high conductivity (EC up to 24,500 uS/cm) have been identified in this place. This fact allows highly specialised and comparatively rare botanical species to grow in this area. These saline soils follow a north-south line-up. The geophysical data, obtained with a field conductivemeter (EM 31), show that this superficial line-up continues in the subsoil. In addition to this, the conductivity cartography, made for an electromagnetic exploration depth of 6 meters, shows that the width of the region where these salinity anomalies take place increases in depth. When included in the hidrogeological context of this sector of the Selva Basin, these data bring new elements for the study of the genesis and working of these marshy environments. The model that future research will have to confirm, maintains that the groundwater discharges coming from the underlying hydrogeothermal aquifer are a conditioning factor of the aforementioned phenomenon. This ascending flow of highly mineralised waters (TDS of about 3,500 mg/l) can produce and keep stable the soil salinity

Avaluació dels recursos d'àrids disponibles en medis fluvials mitjançant tècniques geofisiques. Aplicació a la cubeta de Celrà (Riu Ter, Ne Catalunya)

The depth of the water table and the clay content are determinant factors for the exploitability of natural aggregates, such as the alluvial sands and gravels found on the fluvial domain of the Ter River. In this preliminary study, carried out in the Celri basin, we conclude that these variables can be determined by means of geophysical methods and recornmends the use of such methods in studies of regional character

Investigación geofísica de los paleovalles pleistocenos del NE de Cataluña: el ejemplo de la Riera de Tossa (Costa Brava meridional)

The geometry of Riera de Tossa (Costa Brava, Catalonia) Pleistocene paleovalley has been studied by two geophysical prospecting methods: vertical electric sounding (VES-DC) and seismic refraction. The results show the existence of a sudden slope change of the thalweg that permits to differentiate two sections where erosion processes operated in unequal intensity. Based on geological and geomorphological available data, it can be inferred that this slope rupture is caused by the litological control imposed by the alineation of resistant materials, which limited the headward erosion extend of the creek during the Upper Pleistocene

Robustness against large-scale failures in communications networks

This thesis studies robustness against large-scale failures in communications networks. If failures are isolated, they usually go unnoticed by users thanks to recovery mechanisms. However, such mechanisms are not effective against large-scale multiple failures. Large-scale failures may cause huge economic loss. A key requirement towards devising mechanisms to lessen their impact is the ability to evaluate network robustness. This thesis focuses on multilayer networks featuring separated control and data planes. The majority of the existing measures of robustness are unable to capture the true service degradation in such a setting, because they rely on purely topological features. One of the major contributions of this thesis is a new measure of functional robustness. The failure dynamics is modeled from the perspective of epidemic spreading, for which a new epidemic model is proposed. Another contribution is a taxonomy of multiple, large-scale failures, adapted to the needs and usage of the field of networking.

Impactos de la liberalización del mercado de telefonía fija en Ecuador 2001-2007

El proceso de liberalización del mercado de telefonía fija en Ecuador tenía como finalidad la introducción de la competencia en un mercado donde las empresas de telecomunicaciones de propiedad del Estado ecuatoriano mantienen el monopolio en la prestación del servicio de telefonía fija. Este proceso estuvo siempre delineado por los 10 lineamientos del Consenso de Washington, basados a su vez en los preceptos de la economía liberal de mercado. Con las recomendaciones planteadas, en Ecuador se dio inicio al proceso de liberalización del mercado de la telefonía fija, para lo cual se realizaron varias reformas normativas para permitir la participación del sector privado en el sector de las telecomunicaciones fijas, y la introducción de la competencia en el mercado de telefonía fija. Sin embargo, a pesar de las reformas, el proceso de liberalización del mercado de telefonía fija en Ecuador no logró cumplir con las expectativas por varios factores atribuibles directamente a la gestión del Estado que no supo aplicar adecuadamente el modelo económico propuesto. Entre estos factores se pueden mencionar el fracaso en la privatización de las empresas de telefonía estatales, la débil actuación del Regulador para que se logren acuerdos de interconexión oportunos y eficaces, la ingerencia política en la dirección de las empresas estatales, y la no eliminación de tarifas subsidiadas.

Caracterización de la PYME familiar en la ciudad de Quito

Las pequeñas y medianas empresas juegan un rol muy importante en la economía de un país. En muchos casos es el grupo predominante de empresas, siendo una gran fuente de ingresos y de empleo; una gran mayoría de estas empresas son de carácter familiar y en la realidad, pocas sobreviven, debido a la dificultad de diferenciar las relaciones familiares con la rentabilidad de la empresa. El objetivo de una organización, cualquiera que sea su misión, es generar dinero mientras que la familia tiene como fin la convivencia y el crecimiento de sus miembros en todo ámbito, es por esto que se superpone el lazo familiar al objetivo empresarial; de allí la importancia de conocer a profundidad las principales características de la PYME familiar y como las mismas influyen en la rentabilidad y desarrollo de una organización. La investigación pretende generar información veraz sobre las características organizacionales de la PYME familiar ecuatoriana, para así contrastarla con el modelo común establecido por varios autores; finalmente se busca establecer un modelo característico de la Pyme familiar ecuatoriana.