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Esta tesis tiene como objetivo general desarrollar una herramienta para analizar/predecir condiciones de trabajo de una red de sensores. En particular, se enfoca a un conjunto de dispositivos de vuelo que son parte de sistemas aeroespaciales. El simulador es obtenido por medio de un modelado específico del sistema y su contrastación es realizada a través de un prototipo hardware. La herramienta propuesta permite conseguir medidas previas a la implementación de una etapa experimental definitiva de un dispositivo de vuelo. En particular, en los sistemas aeroespaciales, es necesario cambiar las condiciones de trabajo de los prototipos para predecir el comportamiento y posibles fallos durante la etapa de servicio del hardware definitivo. Conseguir estas condiciones de trabajo puede resultar muy costoso debido al valor de los dispositivos para generarlas. El modelo de simulación provee el medio para extrapolar posibles escenarios operativos sin contar con instrumentos físicos.

Variability in complex systems offering rich set of features is a seriouschallenge to their users in term of flexibility with many possible variants fordifferent application contexts and maintainability. During the long period oftime, much effort has been made to deal with these issues. An effort in thisregard is developing and implementing different variability modelingtechniques.This thesis argues the explanation of three modeling techniques namedconfigurable components, feature models and function-means trees. The maincontribution to the research includes:• A comparison of above mentioned variability modeling techniques in asystematic way,• An attempt to find the integration possibilities of these modelingtechniques based on literature review, case studies, comparison,discussions, and brainstorming.The comparison is based on three case studies each of which is implemented inall above mentioned three modeling techniques and a set of generic aspects ofthese techniques which are further divided into characteristics. At the end, acomprehensive discussion on the comparison is presented and in final sectionsome integration possibility are proposed on the basis of case studies,characteristics, commonalities and experience gained through theimplementation of case studies and literature review.

Permeable Friction Course (PFC) is a layer of porous asphalt pavement with a thickness of up to 50 millimeters overlain on a conventional impervious hot mix asphalt or Portland cement concrete roadway surface. PFC is used for its driver safety and improved stormwater quality benefits associated with its ability to drain rainfall runoff from the roadway surface. PFC has recently been approved as a stormwater best management practice in the State of Texas. The drainage properties of PFC are typically considered to be governed primarily by two hydraulic properties: porosity and hydraulic conductivity. Both of these hydraulic properties are expected to change over the life of the PFC layer due to clogging of the pore space by trapped sediment. Therefore, proper measurement of the hydraulic properties can be problematic. Laboratory and field tests are necessary for accurately determining the hydraulic conductivity of the PFC layer in order to ensure whether the driver safety and water quality benefits will persist in the future. During testing, PFC experiences a nonlinear flow relationship which can be modeled using the Forchheimer equation. Due to the two-dimensional flow patterns created during testing, the hydraulic conductivity cannot be directly measured. Therefore, numerical modeling of the two-dimensional nonlinear flow relationship is required to convert the measureable flow characteristics into the theoretical flow characteristics in order to properly determine the isotropic hydraulic conductivity. This numerical model utilizes a new scalar quantity, defined as the hydraulic conductivity ratio, to allow for proper modeling of nonlinear flow in two-dimensional cylindrical coordinates. PFC core specimens have been extracted from three different roadway locations around Austin, Texas for the past four years (2007 to 2010). Porosity values of the core specimens range from 12% to 23%, and the porosity data suggest a statistical decrease over time due to trapped sediment in the pore space. A series of constant head tests used in the laboratory and a falling head test used in the field are recommended for measurement of PFC hydraulic characteristics using a modified Forchheimer equation. Through numerical modeling, regressions equations are presented to estimate the hydraulic conductivity and nonlinear Forchheimer coefficient from the measureable hydraulic characteristics determined during experimental testing. Hydraulic conductivity values determined for laboratory core specimens range from 0.02 centimeters per second (cm/s) to nearly 3 cm/s. Field measurements of in-situ hydraulic conductivity vary over a range from 0.6 cm/s to 3.6 cm/s. The results of this research provide well-defined laboratory and field methods for measurement of the isotropic hydraulic conductivity of PFC experiencing two-dimensional nonlinear flow and characterized by the Forchheimer equation. This methodology utilizes a numerical model which presents a proper solution for nonlinear flow in two-dimensions. / text

El objetivo de este trabajo es la definición de una metodología para la representación y análisis del comportamiento de tiempo real de sistemas que han sido diseñados utilizando el paradigma de orientación a objetos. La metodología que se propone, denominada UML-MAST, concilia las diferencias entre la visión del diseñador de sistemas de tiempo real y la del de sistemas orientados a objetos. A tal fin define un nivel de abstracción adecuado para los elementos de modelado del comportamiento de tiempo real, que permite formularlos con una estructura paralela a la arquitectura lógica del sistema, y vincularlos a esta. La semántica de modelado sigue el perfil UML para planificabilidad, rendimiento y tiempo (SPT) estandarizado por el OMG, del que UML-MAST puede considerase una implementación. La propuesta se integra con las herramientas de análisis y diseño de sistemas de tiempo real MAST (Modeling and Analysis Suite for Real-Time Applications), que analiza los modelos y retorna los resultados al modelo inicial para su interpretación por el diseñador. Asimismo, se han definido criterios para la extensión de esta metodología a otros niveles de abstracción tales como sistemas basados en componentes y sistemas implementados utilizando Ada 95. Parte de los resultados de este trabajo han sido incorporados por el OMG a su perfil SPT. / The main objective of this work has been the definition of a methodology for the representation and analysis of the timing behaviour of real-time distributed systems designed following the object oriented paradigm. The methodology proposed is called UML-MAST, and reconciles the mismatch between the visions of the object oriented designer and the real-time systems designer. To get this, it has been developed a particular level of abstraction that holds all the modelling elements needed to represent real-time behaviour, structuring the models following the logical architecture of the system. The semantics of the modelling elements follows the "UML Profile for Schedulability, Performance and Time" (SPT), a standard of the Object Management Group (OMG) to which this thesis has reported a number of contributions. UML-MAST can also be considered a particular specialization of its schedulability analysis sub-profile. UML-MAST is integrated in the framework of the Modeling and Analysis Suite for Real-Time Applications (MAST), a modelling environment with a set of tools that enable the analysis of a model and the recovery of its results in it. Criteria for the extension of the methodology to higher levels of abstraction have been defined. As examples, its extension to the modelling of component-based systems as well as to distributed systems developed with Ada95 have been explored and formulated.