La cromatografía es una técnica analítica que permite realizar la separación de mezclas complejas basadas en interacciones fisicoquímicas de los analitos, arrastradas por una fase móvil. En el caso de la GC se utiliza un gas inerte con una fase estacionaria contenida en una columna capilar que es donde ocurre la separación. Los analitos se separan de manera diferencial y eluyen a diferentes tiempos, lo que se conoce como tiempo de retención. De ahí continúan hacia el detector para ser analizados. Por su parte, la espectrometría de masas es una técnica de análisis que permite determinar la distribución de las moléculas de una sustancia de acuerdo a su masa. El espectrómetro de masas es un dispositivo que permite analizar con gran precisión la composición de diferentes elementos químicos e isótopos atómicos, separando los iones de las sustancias en función de su relación masa/carga (m/z).

Como parte del proyecto productivo Nuevo Villanueva, desarrollado en este municipio de Santander, se elaboró esta cartilla orientada a los pequeños productores de fríjol de la región. Debido a que el cultivo del fríjol representa un soporte socioeconómico para los campesinos de Santander y al incremento que este ha tenido en los últimos años, se quiere capacitar técnicamente a los productores de semilla de fríjol, ya que la producción de este cultivo ha venido disminuyendo debido a la calidad del material de propagación que usan los agricultores. Por lo planteado anteriormente, este manual pretende guiar al productor a cerca de las técnicas establecidas en la producción de semilla para conservar las características originales de variedades adaptadas a la zona, aumentar márgenes de producción y a su vez, incrementar los ingresos del agricultor.

La base fundamental de cualquier cultivo es la semilla. De su calidad física y genética depende en buena parte el éxito de una siembra. En algodón, desde hace muchos anos, primero por el Gobierno y posterior-mente por las entidades gremiales, se ha tenido una gran preocupación por el suministro de semillas de buena calidad. La mas antigua referencia que se tiene del control de semillas para siembra, data del año 1952.

Se hace una revisión de los servicios que presta el Instituto Colombiano Agropecuario, ICA, al sector agropecuario, en relación con la protección vegetal, la sanidad animal y el control de la calidad de insumos agropecuarios y semillas. Se indica el marco institucional de la entidad, su organización y funciones y los servicios que presta. Se señala el papel que desempeñan las áreas administrativa y financiera y las oficinas asesoreas de la Gerencia General. Igualmente se destaca el cubrimiento nacional de los servicios, las sedes regionales y centros de diagnóstico

El año de 1998 se constituyó el Acuerdo de Competitividad de la Cadena Láctea Colombiana, el cual se precedió de un trabajo con el apoyo y decidida participación de los Ministerios de Agricultura y Desarrollo Rural, Comercio Exterior, Desarrollo Económico y Salud, así como también el Instituto Interamericano de Cooperación para la Agricultura, IICA, Acoleche, Analac, Asociación de Procesadores Independientes de Leche; Cámara de Industria de Alimentos de la ANDI, Fedecoleche y Fedegan. Este fue el primer paso para concertar entre el sector productivo y el Gobierno Nacional. Este Acuerdo está constituido por estrategias, proyectos y acciones que comprometen al Gobierno, ganaderos, industriales Y cooperativas con una política de concertación, consenso y competitividad. Uno de los resultados del Acuerdo fue la Creación del Consejo Nacional Lácteo Colombiano, como organismo administrador de éste y promotor del desarrollo del sector, que además de fijar los precios de la leche, dio confianza para la inversión privada y permitió el arranque al desarrollo industrial de la leche en Colombia.

This research is part of the project entitled ""CANOPOR"". Overall, this project aims to carry out studies of forest canopy dynamics through Airborne LiDAR scanning. From this perspective, this study focus on developing a methodology for segmentation automatic or semi-automatic tree crowns in tropical rain forest. The study area corresponds to Paracou experimental in French Guiana. On this scenario, a combination of combination of high resolution optical images and LiDAR scanners is used. The present document provides full details about the pre-treatment process, images treatment, results and comparisons with different segmentation approaches. The validation method is also discussed. Results revealed that the use of LiDAR and variables such as elevation and intensity are a valuable source of information for understanding the structure of complex ecosystems in tropical forests. 

The main challenge of this Thesis is to reliably preserve quality of service (QoS) contracts in component-based software systems under changing conditions of system execution. In response to this challenge, the presented contribution is twofold. The first is a model for component-based software applications, QoS contracts and reconfiguration rules as typed attributed graphs, and the definition of QoS-contracts semantics as state machines in which transitions are performed as software reconfigurations. Thus, we effectively use (formal) models at runtime to reliably reconfigure software applications for preserving its QoS contracts. More specifically, we show the feasibility of exploiting design patterns at runtime in reconfiguration loops to fulfill expected QoS levels associated to specific context conditions. We realize this formal model through a component-based architecture and implementation that can be used as an additional layer of SCA middleware stacks to preserve the QoS contracts of executed applications.  The second contribution is the characterization of adaptation properties to evaluate self-adaptive software systems in a standardized and comparable way. By its own nature, the adaptation mechanisms of self-adaptive software systems are essentially feedback loops as defined in control theory. Thus, it results reasonable to evaluate them using the standard properties used to evaluate feedback loops, re-interpreting these properties for the software domain. We define the relibility of our formal model realization in terms of a subset of the characterized adaptation properties, and we show that these properties are guaranteed in this realization.

Wind power is one of the key players in the European Union target of 20% share of energy from renewable sources in 2020 to reduce greenhouse gas emissions and dependence on energy supply. In order to accomplish such target, some European countries are placing the wind farms further from the coast to exploit the higher wind speeds at open sea. However the traditional transmission system for offshore wind farms based on High Voltage Alternate Current (HVAC) is not appropriate for long distances. Hence, this research work was carried out to examine and determine the most suitable transmission system for offshore wind farms in terms of technical, environmental and economic costs. The methodological approach employed in the investigations was arranged in two parts. First, a quantitative and qualitative method of literature review involving critical examination of documented information and experiences of the two commercially available transmission systems: HVAC and HVDC (High Voltage Direct Current); second, a quantitative method that investigates and analyzes an adequate transmission system for a propose an offshore wind cluster in terms of economic and environmental costs. From the analysis, HVDC based on Voltage Source Converters (VSC) exhibited technical superiority over HVAC for long distance submarine transmission, control of active and reactive power, grid support and connection of asynchronous grids. Furthermore, in the proposed offshore wind farm cluster of 1 GW of installed capacity located at 150 km from the point of connection, after a distance of 90 km HVDC becomes more economic due to reduced system losses, and after a distance of 125 km HVDC presents lower environmental impacts associated with the raw materials used in the transmission system. At such point, particular to each transmission project, VSC-HVDC surpasses HVAC in technical, environmental and economic terms.

With the advent of ubiquitous computing, interaction design has broadened its object of inquiry into how smart computational artifacts inconspicuously act in  people’s everyday lives. Although user-centered design approaches remains useful for exploring how people cope with interactive systems, they cannot explain how this new breed of artifact participates in people’s sociality. User-centered design approach assumes that humans control interactive systems, but neglects any possibility of the agency of smart artifacts.Following Actor-network Theory, this research recognizes that artifacts and humans share the capacity of influencing society and meshing with each other, constituting hybrid social actors. From that standpoint, the research offers a triadic structure of networked social interaction as a methodological basis to investigate how smart devices perceive their social setting and adaptively mediate people’s interactions within activities. These triadic units of analysis account for the interactions within and between humannonhuman collectives in the actor-network. The within interactions are those that hold together humans and smart artifacts inside a collective and put forward the collective’s assembled meaning for other actors in the network.The between interactions are those that occur among collectives and characterize the dominant relational model of the actor-network. This triadic approach was modeled and used to analyze the interactions of participants in three empirical studies of social activities with communal goals, each mediated by a smart artifact that enacted – signified – a balanced distribution of obligations and privileges among subjects. Overall, the studies found that actor-networks exhibit a social viscosity that hinders people’s interactions. This is because when people try to collectively accomplish goals, they offer resistance to one another. The studies also show that the intervention of smart artifacts can facilitate the achievement of cooperative and collaborative interaction between actors when the artifacts enact the dominant moral principles which prompt the preservation of social balance, enhance the network’s information integrity, and are located at the focus of activity. The articulation of Actor-Network Theory principles with interaction design methods opens up the traditional user-artifact dyad towards triadic collective enactment by embracing diverse kinds of participants and practices, thus facilitating the design of enhanced sociality. The theoretical conceptual framework, methods and tools developed in this research are relevant to product and interaction designers, ubiquitous computing and Science and technology studies (STS) researchers; as well as practitioners interested in making the interaction between humans and computers smarter, more intuitive and more enjoyable. The outcome of this research is addressed to designers, engineers and urban planners who are responsible for the design of the new generation of computational artifacts that will cohabitate today’s transportation terminals and vehicles, offices, parks, streets, among other social spaces of the constructed world.

The following report describes the work done during my internship in AlbaTERN Ltd, a company focused in the design and construction of wave energy devices that capture energy from ocean waves and convert it into sustainable low- carbon electricity. A background of existing research in the area of Wave Energy conversion and its potential around the world is given in the first chapters. The main objective of my thesis has been support the design and construction of a unique wave energy conversion system constructed from multiple SQUID modules in a hexagonal array configuration. The project has been focused to look specifically at improving the hydraulic energy conversion efficiency, the feasibility of auto-setting operational variables according to the sea conditions, and the overall adaptability of the design to suit the specifications of the site and power requirements. Simulations using SimHydraulics have been developed to assess the design an optimal Hydraulic energy conversion system. With the output of the several simulations and hydraulic laboratory tests have been possible the sizing of its different components, and the design of special manifold blocks with self-setting hydraulic control, reducing the quantity and complexity the electronic devices for the general control. The key challenge facing the Wave Energy conversion Industry is lowering the cost of energy generation, where is required research and Development in order to design a device with high efficiency, high availability and low cost for the mass production. So achieving a viable wave energy future depends as much upon developing a technology that can be rapidly and economically scaled to high volume production. This project provides a solid foundation for scaling WaveNET arrays in excess of 10 MW.