Diseño de una propuesta de modificaciones regulatorias para la introducción de los operadores móviles virtuales en el Ecuador

Las redes de telecomunicaciones móviles han experimentado un crecimiento vertiginoso en los últimos años, logrando niveles de penetración y demanda que han sobrepasado los pronósticos más optimistas. La implementación de redes de telecomunicaciones móviles depende de manera indispensable de la utilización de un recurso natural estratégico, como es el espectro radioeléctrico. El modelo tradicional de planificación centralizada para la gestión y administración de este recurso, ha sido paulatinamente desplazado por otros modelos basados en los conceptos de eficiencia económica, como es el denominado mercado secundario del espectro, u otros más modernos que promueven el libre acceso de la población a este recurso natural. La evolución de los mecanismos para administrar y gestionar el espectro ha sido posible gracias a la investigación y desarrollo de nuevas técnicas en la utilización de este recurso, que han logrado desplazar la demanda desde los servicios tradicionales de voz hacia servicios más atractivos como los de mensajería corta SMS, acceso a Internet móvil, acceso a redes sociales, geo-posicionamiento y otros que continúan incrementando el interés de la población en utilizar las redes móviles y, obviamente los ingresos de los operadores móviles. El mercado de las telecomunicaciones móviles ofrece la posibilidad cierta de introducción de nuevos operadores, para lo cual es necesario establecer mecanismos regulatorios que permitan la utilización eficiente de los recursos naturales y de la infraestructura necesaria para prestar estos servicios.Una de los problemas fundamentales en el ingreso de nuevos operadores en el mercado, es la escasez de espectro radioeléctrico, que imposibilita el otorgar títulos habilitantes para que nuevos operadores de telecomunicaciones móviles ingresen en el mercado. Sin embargo, el desarrollo tecnológico y regulatorio, permite nuevos modelos de gestión de este recurso fundamental para el ingreso de nuevos actores en el mercado, la compartición de segmentos de espectro, la liberación de bandas de frecuencias para que sean utilizadas por todo el público, impulsa el ingreso de los denominados Operadores Móviles Virtuales. En esta Tesis se analizarán de manera fundamental las barreras regulatorias que deberían eliminarse para que se produzca el ingreso efectivo de nuevos operadores móviles virtuales en el mercado, proponiendo modificaciones regulatorias en los temas relacionados con la administración y gestión de dos elementos fundamentales: el espectro radioeléctrico y las infraestructuras necesarias para la implementación de las redes de telecomunicaciones de los nuevos operadores.

Crisis petrolera e imperialismo: la política de seguridad energética de Bush y sus implicaciones para Latinoamérica

El Gobierno de George W. Bush diseñó una nueva política energética para los Estados Unidos (EUA) como respuesta a la creciente escasez de petróleo en el mundo, evidenciada en los últimos años por la tendencia al alza de sus precios en el mercado internacional. Esta situación, sumada a la dependencia de los EUA respecto al abastecimiento externo de crudo, a la importancia de este recurso en su matriz energética, a la concentración geográfica de su producción y reservas y a la competencia geo política con otros Estados, ha propiciado el resurgimiento del tema energético dentro de las prioridades de seguridad nacional de los EUA. Dado que América Latina cuenta con vastas reservas de crudo, y que la región cons tituye una zona de influencia natural para los EUA, las dinámicas de la seguridad energética de este país han generado un pro ceso dialéctico con las políticas internas de los países latinoamericanos, particularmente de aquellos que cuentan con las reservas más importantes de la región: Brasil, Venezuela y México. El libro centra su análisis en las relaciones exteriores de los EUA con estas tres naciones latinoamericanas, con el fin de determinar el nuevo papel que la región ha pasado a jugar en los cálculos geopolíticos estadounidenses.

Portuñol salvaje: arte licuafronteras y tensiones contemporáneas (Dossier: Literaturas de la integración, el Sur y su diversidad)

Pensar, escribir, cantar, vivir entre idiomas. Producir conocimiento desde zonas limítrofes, desde lugares y desde memorias y saberes múltiples. En este texto se busca indagar los sentidos que se insinúan en un conjunto de prácticas artísticas (literarias, visuales, musicales) que se gestan en torno a lo que se ha bautizado como portuñol salvaje. Para ello, luego de una caracterización del portuñol, se busca evidenciar la recurrencia de un gesto artístico que deviene producción de conocimiento. Se plantea que, consideradas en conjunto y a partir del contexto geocultural en el que surgen, dichas prácticas constituyen un fecundo aporte para comprender una serie de aspectos sociales, culturales, económicos y políticos de nuestras sociedades.

El Plan Colombia: historia local / diseño global; análisis del discurso en perspectiva decolonial

Este trabajo apunta a evidenciar la representación del Plan Colombia en Colombia y en Estados Unidos, a partir de la promesa retórica de la pacificación forzosa para hacer viable la prosperidad democrática como paso obligado para lograr el fortalecimiento del Estado. El Plan Colombia se vislumbra en este estudio, insertado en un diseño global imperial que ilustra por analogía un patrón de dominación que opera con estrategias discursivas equiparables en otras partes del planeta, donde la intervención militar, económica y cultural del poder contemporáneo impone discursos, a través del poder simbólico, la seducción y la fuerza militar, económica y jurídica. Como entrada metodológica se presenta el sistema-mundo moderno, la macroestructura de la colonialidad del poder y los elementos teóricos que soportan la perspectiva decolonial del análisis del discurso; la propuesta conceptual de la heterogeniedad histórica estructural planteada por Quijano, y la Teoría Crítica de la Cultura, elaborada por Santiago Castro-Gómez. Se ubica a Colombia en su sitio en la jerarquía de poder del sistema mundo y se introducen los principales elementos contextuales tanto históricos como presentes, en los cuales se desarrolla el Plan Colombia. Se analiza el impacto de la lucha global contra las drogas y el terrorismo global como ejes principales de articulación simbólica y discursiva para justificar la implementación del Plan desde dos historias locales, la de los Estados Unidos y la de Colombia, enmarcados en uno de los diseños globales y guerras privadas del Siglo XXI. Se aborda el tema de la hegemonía política en el sistema-mundo y su estructura a nivel local y global. La dimensión geopolítica que permite la continuidad de las hegemonías globales y locales se estructura desde discursividades e imaginarios simbólicos inscritos en ellas, tanto desde los diseños globales imperiales como desde las historias locales, manipuladas políticamente por las élites económicas y políticas de los Estados Unidos y por la élites del Tercer Mundo. La promesa para Colombia de avanzar en el esquema del sistema – mundo moderno hacia la semiperiferia, impulsó al Estado colombiano a profundizar el conflicto armado de más de 50 años de duración, entre otros, gracias al aporte militar, al apoyo técnico y al respaldo a Colombia de los Estados Unidos a través del Plan Colombia. En este contexto ¿Cómo entender y develar las intencionalidades del Plan Colombia de sus gestores globales y de quienes lo apoyan en Colombia y en Estados Unidos? A través del análisis discursivo en perspectiva decolonial, situado histórica y contextualmente, el texto se adentra en las respuestas de éstas y otras preguntas relacionadas con el esquema de dominación global contemporáneo. La perspectiva de análisis decolonial apunta al desmonte del modelo civilizatorio occidental euroestadounidense pues no es cierto que exista una sola tradición epistémica de la que se derive la verdad y la universalidad, aunque el totalitarismo colonial autoritario de occidente se haya erigido como universal obligatorio para todos. Se toma a “occidente” como referente epistemológico que nos rige porque es en occidente y a través de occidente que se ha enquistado la colonialidad del poder en el mundo, derivada del proyecto moderno colonial eurocéntrico, perpetuado a través del tiempo y que se mantiene en el Siglo XXI. La aproximación al Plan Colombia se presenta desde la jerarquía geopolítica y geo cultural para el caso colombiano, así como su lugar en el mundo de acuerdo con el esquema centro – periferia – semiperiferia de dicho sistema. Lo anterior implica ubicar a Colombia en el sistema-mundo, teniendo en cuenta la matriz colonial de larga duración que nació con la invasión a América y que se perpetúa hasta hoy en el Estado nación colombiano, a través de los esquemas de dominación física, de poder material y de control simbólico.

La Doctrina Monroista de Estados Unidos de Norteamérica y el Unionismo latinoamericano: historia de una asimetría

La derrota de Napoleón Bonaparte fue el antecedente del congreso de Viena (1814-1815) en cuyo seno se intentó restaurar la Europa pre revolucionaria y equilibrar el poder geopolítico de la región abriendo la posibilidad de enfrentar a quienes estuvieran dispuestos a desestructurar las monarquías; aquella voluntad geo-politica-económica estuvo diseñada, además, para incidir en América en donde diversos sectores procuraban las independencias del coloniaje europeo que a su vez, en esos mismos años, reforzó su conducta a causa del “imperio de los cien días de Napoleón” y de la conformación de la triple y de la cuádruple alianzas. La referida determinación europea y sus coletazos históricos, formaron parte, luego en 1823, de la justificación para que los Estados Unidos de América pretendiera erigirse en defensor de los países Americanos. Tal política, expresada por el Presidente Monroe, escondió la visión expansionista que habría de marcar, hasta hoy, la relación entre Estados Unidos y el resto del Continente. Ante la circunstancia provocada en 1823, fue convocado, en 1826, por el Libertador Bolívar, el Congreso de Panamá como una respuesta al proyecto expansionista en ciernes y a fin de edificar el proceso unionista que intentó construirse con la presencia de los países que habían logrado en América sus independencias. Desde entonces estas dos concepciones asimétricas -la de la doctrina Monroe y de la unidad latinoamericana- han marcado la huella de la región americana que aún batalla por su autodeterminación.

Effects of Gunnison Sage-Grouse habitat treatment efforts on associated avifauna and vegetation structure

Conservation efforts over the last 20 years for the Gunnison Sage-Grouse (Centrocercus minimus) have involved extensive habitat manipulations done predominantly to improve brood rearing habitat for the grouse. However, the effects of Gunnison Sage-Grouse habitat treatments on sympatric avifauna and responses of vegetation to manipulations are rarely measured, and if they are, it is immediately following treatment implementation. This study examined the concept of umbrella species management by retrospectively comparing density and occupancy of eight sagebrush associated songbird species and six measures of vegetation in treated and control sites. Our results suggested that songbird densities and occupancy changed for birds at the extreme ends of their association with sagebrush and varied with fine-scale habitat structure. We found Brewer’s Sparrows (Spizella breweri) decreased in density on treated sites and Vesper Sparrows (Pooecetes gramineus) increased. Occupancy estimation revealed that Brewer’s Sparrows and Green-tailed Towhees (Pipilo chlorurus) occupied significantly fewer treated points whereas Vesper Sparrows occupied significantly more. Vegetation comparisons between treated and control areas found shrub cover to be 26% lower in treated sites. Lower shrub cover in treated areas may explain the differences in occupancy and densities of the species sampled based on known habitat needs. The fine-scale analysis showed a negative relationship to forb height and cover for the Sage Sparrow (Amphispiza belli) indicating, from vegetation measures showing grass and forb cover during a good precipitation year covered significantly more area in the treatment than the control sites, that Sage Sparrows may also not respond favorably to Gunnison Sage-Grouse habitat treatments. While the concept of an umbrella species is appealing, evidence from this study suggests that conservation efforts aimed at the Gunnison Sage-Grouse may not be particularly effective for conserving other sagebrush obligate species of concern. This is probably due to Gunnison Sage-Grouse habitat management being focused on the improvement of brood rearing habitat which reduces sagebrush cover and promotes development of understory forbs and grasses.

Incorporating Legacy Soil pH Databases into Digital Soil Maps

Soil data and reliable soil maps are imperative for environmental management. conservation and policy. Data from historical point surveys, e.g. experiment site data and farmers fields can serve this purpose. However, legacy soil information is not necessarily collected for spatial analysis and mapping such that the data may not have immediately useful geo-references. Methods are required to utilise these historical soil databases so that we can produce quantitative maps of soil propel-ties to assess spatial and temporal trends but also to assess where future sampling is required. This paper discusses two such databases: the Representative Soil Sampling Scheme which has monitored the agricultural soil in England and Wales from 1969 to 2003 (between 400 and 900 bulked soil samples were taken annually from different agricultural fields); and the former State Chemistry Laboratory, Victoria, Australia where between 1973 and 1994 approximately 80,000 soil samples were submitted for analysis by farmers. Previous statistical analyses have been performed using administrative regions (with sharp boundaries) for both databases, which are largely unrelated to natural features. For a more detailed spatial analysis that call be linked to climate and terrain attributes, gradual variation of these soil properties should be described. Geostatistical techniques such as ordinary kriging are suited to this. This paper describes the format of the databases and initial approaches as to how they can be used for digital soil mapping. For this paper we have selected soil pH to illustrate the analyses for both databases.

Land use for England and Wales: evaluation of management options to support 'good ecological status' in surface freshwaters

This paper analyses historic records of agricultural land use and management for England and Wales from 1931 and 1991 and uses export coefficient modelling to hindcast the impact of these practices on the rates of diffuse nitrogen (N) and phosphorus (P) export to water bodies for each of the major geo-climatic regions of England and Wales. Key trends indicate the importance of animal agriculture as a contributor to the total diffuse agricultural nutrient loading on waters, and the need to bring these sources under control if conditions suitable for sustaining 'Good Ecological Status' under the Water Framework Directive are to be generated. The analysis highlights the importance of measuring changes in nutrient loading in relation to the catchment-specific baseline state for different water bodies. The approach is also used to forecast the likely impact of broad regional scale scenarios on nutrient export to waters and highlights the need to take sensitive land out of production, introduce ceilings on fertilizer use and stocking densities, and controls on agricultural practice in higher risk areas where intensive agriculture is combined with a low intrinsic nutrient retention capacity, although the uncertainties associated with the modelling applied at this scale should be taken into account in the interpretation of model output. The paper advocates the need for a two-tiered approach to nutrient management, combining broad regional policies with targeted management in high risk areas at the catchment and farm scale.

From the sun to the Earth: The 13 May 2005 coronal mass ejection

We report the results of a multi-instrument, multi-technique, coordinated study of the solar eruptive event of 13 May 2005. We discuss the resultant Earth-directed (halo) coronal mass ejection (CME), and the effects on the terrestrial space environment and upper Earth atmosphere. The interplanetary CME (ICME) impacted the Earth’s magnetosphere and caused the most-intense geomagnetic storm of 2005 with a Disturbed Storm Time (Dst) index reaching −263 nT at its peak. The terrestrial environment responded to the storm on a global scale. We have combined observations and measurements from coronal and interplanetary remote-sensing instruments, interplanetary and near-Earth in-situ measurements, remote-sensing observations and in-situ measurements of the terrestrial magnetosphere and ionosphere, along with coronal and heliospheric modelling. These analyses are used to trace the origin, development, propagation, terrestrial impact, and subsequent consequences of this event to obtain the most comprehensive view of a geo-effective solar eruption to date. This particular event is also part of a NASA-sponsored Living With a Star (LWS) study and an on-going US NSF-sponsored Solar, Heliospheric, and INterplanetary Environment (SHINE) community investigation.

GIS in the cloud: implementing a web map service on Google App Engine

Many producers of geographic information are now disseminating their data using open web service protocols, notably those published by the Open Geospatial Consortium. There are many challenges inherent in running robust and reliable services at reasonable cost. Cloud computing provides a new kind of scalable infrastructure that could address many of these challenges. In this study we implement a Web Map Service for raster imagery within the Google App Engine environment. We discuss the challenges of developing GIS applications within this framework and the performance characteristics of the implementation. Results show that the application scales well to multiple simultaneous users and performance will be adequate for many applications, although concerns remain over issues such as latency spikes. We discuss the feasibility of implementing services within the free usage quotas of Google App Engine and the possibility of extending the approaches in this paper to other GIS applications.

In vitro fermentation of carbohydrates by porcine faecal inocula and their influence on Salmonella Typhimurium growth in batch culture systems

The aim of this study was to evaluate in vitro the influence of fermentable carbohydrates on the activity of porcine microbiota and survival of Salmonella Typhimurium in a batch culture system simulating the porcine hindgut. The carbohydrates tested were xylooligosaccharides, a mixture of fructooligosaccharides/inulin (FIN), fructooligosaccharides (FOS), gentiooligosaccharides (GEO) and lactulose (LAC). These ingredients stimulated the growth of selected Bifidobacterium and Lactobacillus species in pure cultures. In batch cultures, the carbohydrates influenced some fermentation parameters. For example, GEO and FIN significantly increased lactic acids compared with the control (no added carbohydrate). With the exception of LAC, the test carbohydrates increased the production of short-chain fatty acid (SCFA) and modified SCFA profiles. Quantitative analysis of bacterial populations by FISH revealed increased counts of the Bifidobacterium group compared with control and, with exception of FOS, increased Lactobacillus, Leuconostoc and Weissella spp. counts. Salmonella numbers were the lowest during the fermentation of LAC. This work has looked at carbohydrate metabolism by porcine microbiota in a pH-controlled batch fermentation system. It provides an initial model to analyse interactions with pathogens.

Proof of concept of automated mapping of weeds in arable fields

The project investigated whether it would be possible to remove the main technical hindrance to precision application of herbicides to arable crops in the UK, namely creating geo-referenced weed maps for each field. The ultimate goal is an information system so that agronomists and farmers can plan precision weed control and create spraying maps. The project focussed on black-grass in wheat, but research was also carried out on barley and beans and on wild-oats, barren brome, rye-grass, cleavers and thistles which form stable patches in arable fields. Farmers may also make special efforts to control them. Using cameras mounted on farm machinery, the project explored the feasibility of automating the process of mapping black-grass in fields. Geo-referenced images were captured from June to December 2009, using sprayers, a tractor, combine harvesters and on foot. Cameras were mounted on the sprayer boom, on windows or on top of tractor and combine cabs and images were captured with a range of vibration levels and at speeds up to 20 km h-1. For acceptability to farmers, it was important that every image containing black-grass was classified as containing black-grass; false negatives are highly undesirable. The software algorithms recorded no false negatives in sample images analysed to date, although some black-grass heads were unclassified and there were also false positives. The density of black-grass heads per unit area estimated by machine vision increased as a linear function of the actual density with a mean detection rate of 47% of black-grass heads in sample images at T3 within a density range of 13 to 1230 heads m-2. A final part of the project was to create geo-referenced weed maps using software written in previous HGCA-funded projects and two examples show that geo-location by machine vision compares well with manually-mapped weed patches. The consortium therefore demonstrated for the first time the feasibility of using a GPS-linked computer-controlled camera system mounted on farm machinery (tractor, sprayer or combine) to geo-reference black-grass in winter wheat between black-grass head emergence and seed shedding.

Final report on research project PS2010, proof of concept of automated mapping of weeds in arable fields

Many weeds occur in patches but farmers frequently spray whole fields to control the weeds in these patches. Given a geo-referenced weed map, technology exists to confine spraying to these patches. Adoption of patch spraying by arable farmers has, however, been negligible partly due to the difficulty of constructing weed maps. Building on previous DEFRA and HGCA projects, this proposal aims to develop and evaluate a machine vision system to automate the weed mapping process. The project thereby addresses the principal technical stumbling block to widespread adoption of site specific weed management (SSWM). The accuracy of weed identification by machine vision based on a single field survey may be inadequate to create herbicide application maps. We therefore propose to test the hypothesis that sufficiently accurate weed maps can be constructed by integrating information from geo-referenced images captured automatically at different times of the year during normal field activities. Accuracy of identification will also be increased by utilising a priori knowledge of weeds present in fields. To prove this concept, images will be captured from arable fields on two farms and processed offline to identify and map the weeds, focussing especially on black-grass, wild oats, barren brome, couch grass and cleavers. As advocated by Lutman et al. (2002), the approach uncouples the weed mapping and treatment processes and builds on the observation that patches of these weeds are quite stable in arable fields. There are three main aspects to the project. 1) Machine vision hardware. Hardware component parts of the system are one or more cameras connected to a single board computer (Concurrent Solutions LLC) and interfaced with an accurate Global Positioning System (GPS) supplied by Patchwork Technology. The camera(s) will take separate measurements for each of the three primary colours of visible light (red, green and blue) in each pixel. The basic proof of concept can be achieved in principle using a single camera system, but in practice systems with more than one camera may need to be installed so that larger fractions of each field can be photographed. Hardware will be reviewed regularly during the project in response to feedback from other work packages and updated as required. 2) Image capture and weed identification software. The machine vision system will be attached to toolbars of farm machinery so that images can be collected during different field operations. Images will be captured at different ground speeds, in different directions and at different crop growth stages as well as in different crop backgrounds. Having captured geo-referenced images in the field, image analysis software will be developed to identify weed species by Murray State and Reading Universities with advice from The Arable Group. A wide range of pattern recognition and in particular Bayesian Networks will be used to advance the state of the art in machine vision-based weed identification and mapping. Weed identification algorithms used by others are inadequate for this project as we intend to collect and correlate images collected at different growth stages. Plants grown for this purpose by Herbiseed will be used in the first instance. In addition, our image capture and analysis system will include plant characteristics such as leaf shape, size, vein structure, colour and textural pattern, some of which are not detectable by other machine vision systems or are omitted by their algorithms. Using such a list of features observable using our machine vision system, we will determine those that can be used to distinguish weed species of interest. 3) Weed mapping. Geo-referenced maps of weeds in arable fields (Reading University and Syngenta) will be produced with advice from The Arable Group and Patchwork Technology. Natural infestations will be mapped in the fields but we will also introduce specimen plants in pots to facilitate more rigorous system evaluation and testing. Manual weed maps of the same fields will be generated by Reading University, Syngenta and Peter Lutman so that the accuracy of automated mapping can be assessed. The principal hypothesis and concept to be tested is that by combining maps from several surveys, a weed map with acceptable accuracy for endusers can be produced. If the concept is proved and can be commercialised, systems could be retrofitted at low cost onto existing farm machinery. The outputs of the weed mapping software would then link with the precision farming options already built into many commercial sprayers, allowing their use for targeted, site-specific herbicide applications. Immediate economic benefits would, therefore, arise directly from reducing herbicide costs. SSWM will also reduce the overall pesticide load on the crop and so may reduce pesticide residues in food and drinking water, and reduce adverse impacts of pesticides on non-target species and beneficials. Farmers may even choose to leave unsprayed some non-injurious, environmentally-beneficial, low density weed infestations. These benefits fit very well with the anticipated legislation emerging in the new EU Thematic Strategy for Pesticides which will encourage more targeted use of pesticides and greater uptake of Integrated Crop (Pest) Management approaches, and also with the requirements of the Water Framework Directive to reduce levels of pesticides in water bodies. The greater precision of weed management offered by SSWM is therefore a key element in preparing arable farming systems for the future, where policy makers and consumers want to minimise pesticide use and the carbon footprint of farming while maintaining food production and security. The mapping technology could also be used on organic farms to identify areas of fields needing mechanical weed control thereby reducing both carbon footprints and also damage to crops by, for example, spring tines. Objective i. To develop a prototype machine vision system for automated image capture during agricultural field operations; ii. To prove the concept that images captured by the machine vision system over a series of field operations can be processed to identify and geo-reference specific weeds in the field; iii. To generate weed maps from the geo-referenced, weed plants/patches identified in objective (ii).

Fast regridding of large, complex geospatial datasets

In the earth sciences, data are commonly cast on complex grids in order to model irregular domains such as coastlines, or to evenly distribute grid points over the globe. It is common for a scientist to wish to re-cast such data onto a grid that is more amenable to manipulation, visualization, or comparison with other data sources. The complexity of the grids presents a significant technical difficulty to the regridding process. In particular, the regridding of complex grids may suffer from severe performance issues, in the worst case scaling with the product of the sizes of the source and destination grids. We present a mechanism for the fast regridding of such datasets, based upon the construction of a spatial index that allows fast searching of the source grid. We discover that the most efficient spatial index under test (in terms of memory usage and query time) is a simple look-up table. A kd-tree implementation was found to be faster to build and to give similar query performance at the expense of a larger memory footprint. Using our approach, we demonstrate that regridding of complex data may proceed at speeds sufficient to permit regridding on-the-fly in an interactive visualization application, or in a Web Map Service implementation. For large datasets with complex grids the new mechanism is shown to significantly outperform algorithms used in many scientific visualization packages.