61 resultados para goal-oriented requirements engineering


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Verifying whether an ontology meets the set of established requirements is a crucial activity in ontology engineering. In this sense, methods and tools are needed (a) to transform (semi-)automatically functional ontology requirements into SPARQL queries, which can serve as unit tests to verify the ontology, and (b) to check whether the ontology fulfils the requirements. Thus, our purpose in this poster paper is to apply the SWIP approach to verify whether an ontology satisfies the set of established requirements.

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Recently a new recipe for developing and deploying real-time systems has become increasingly adopted in the JET tokamak. Powered by the advent of x86 multi-core technology and the reliability of the JET’s well established Real-Time Data Network (RTDN) to handle all real-time I/O, an official Linux vanilla kernel has been demonstrated to be able to provide realtime performance to user-space applications that are required to meet stringent timing constraints. In particular, a careful rearrangement of the Interrupt ReQuests’ (IRQs) affinities together with the kernel’s CPU isolation mechanism allows to obtain either soft or hard real-time behavior depending on the synchronization mechanism adopted. Finally, the Multithreaded Application Real-Time executor (MARTe) framework is used for building applications particularly optimised for exploring multicore architectures. In the past year, four new systems based on this philosophy have been installed and are now part of the JET’s routine operation. The focus of the present work is on the configuration and interconnection of the ingredients that enable these new systems’ real-time capability and on the impact that JET’s distributed real-time architecture has on system engineering requirements, such as algorithm testing and plant commissioning. Details are given about the common real-time configuration and development path of these systems, followed by a brief description of each system together with results regarding their real-time performance. A cycle time jitter analysis of a user-space MARTe based application synchronising over a network is also presented. The goal is to compare its deterministic performance while running on a vanilla and on a Messaging Real time Grid (MRG) Linux kernel.

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Autonomous systems refer to systems capable of operating in a real world environment without any form of external control for extended periods of time. Autonomy is a desired goal for every system as it improves its performance, safety and profit. Ontologies are a way to conceptualize the knowledge of a specific domain. In this paper an ontology for the description of autonomous systems as well as for its development (engineering) is presented and applied to a process. This ontology is intended to be applied and used to generate final applications following a model driven methodology.

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The problem of conceptualisation is the first step towards the identication of the functional requirements of a system. This article proposes two extensions of well-known object oriented techniques: UER (User-Environment-Responsibility) technique and enhanced CRC (Class-ResponsibilityCollaboration) cards. UER technique consists of (a) looking for the users of systems and describing the ways the system is used; (b) looking for the objects of the environment and describing the possible interactions; and (c) looking for the general requirements or goals of the system, the actions that it should carry out without explicit interaction. The enhanced CRC cards together with the internal use cases technique is used for dening collaborations between agents. These techniques can be easily integrated in UML (Unied Modelling Language) [2], dening the new notation symbols as stereotypes.

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The engineer must have sufficient theoretical knowledge to be applied to solve specific problems, with the necessary capacity to simplify these approaches, and taking into account factors such as speed, simplicity, quality and economy. In Geology, its ultimate goal is the exploration of the history of the geological events through observation, deduction, reasoning and, in exceptional cases by the direct underground exploration or experimentation. Experimentation is very limited in Geology. Reproduction laboratory of certain phenomena or geological processes is difficult because both time and space become a large scale. For this reason, some Earth Sciences are in a nearly descriptive stage whereas others closest to the experimental, Geophysics and Geochemistry, have assimilated progress experienced by the physics and chemistry. Thus, Anglo-Saxon countries clearly separate Engineering Geology from Geological Engineering, i.e. Applied Geology to the Geological Engineering concepts. Although there is a big professional overlap, the first one corresponds to scientific approach, while the last one corresponds to a technological one. Applied Geology to Engineering could be defined as the Science and Applied Geology to the design, construction and performance of engineering infrastructures in and field geology discipline. There has been much discussion on the primacy of theory over practice. Today prevails the exaggeration of practice, but you get good workers and routine and mediocre teachers. This idea forgets too that teaching problem is a problem of right balance. The approach of the action lines on the European Higher Education Area (EHEA) framework provides for such balance. Applied Geology subject represents the first real contact with the physical environment with the practice profession and works. Besides, the situation of the topic in the first trace of Study Plans for many students implies the link to other subjects and topics of the career (tunnels, dams, groundwater, roads, etc). This work analyses in depth the justification of such practical trips. It shows the criteria and methods of planning and the result which manifests itself in pupils. Once practical trips experience developed, the objective work tries to know about results and changes on student’s motivation in learning perspective. This is done regardless of the outcome of their knowledge achievements assessed properly and they are not subject to such work. For this objective, it has been designed a survey about their motivation before and after trip. Survey was made by the Unidad Docente de Geología Aplicada of the Departamento de Ingeniería y Morfología del Terreno (Escuela Técnica Superior de Ingenieros de Caminos, Canales y Puertos, Universidad Politécnica de Madrid). It was completely anonymous. Its objective was to collect the opinion of the student as a key agent of learning and teaching of the subject. All the work takes place under new teaching/learning criteria approach at the European framework in Higher Education. The results are exceptionally good with 90% of student’s participation and with very high scores in a number of questions as the itineraries, teachers and visited places (range of 4.5 to 4.2 in a 5 points scale). The majority of students are very satisfied (average of 4.5 in a 5 points scale).

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Telecommunications networks have been always expanding and thanks to it, new services have appeared. The old mechanisms for carrying packets have become obsolete due to the new service requirements, which have begun working in real time. Real time traffic requires strict service guarantees. When this traffic is sent through the network, enough resources must be given in order to avoid delays and information losses. When browsing through the Internet and requesting web pages, data must be sent from a server to the user. If during the transmission there is any packet drop, the packet is sent again. For the end user, it does not matter if the webpage loads in one or two seconds more. But if the user is maintaining a conversation with a VoIP program, such as Skype, one or two seconds of delay in the conversation may be catastrophic, and none of them can understand the other. In order to provide support for this new services, the networks have to evolve. For this purpose MPLS and QoS were developed. MPLS is a packet carrying mechanism used in high performance telecommunication networks which directs and carries data using pre-established paths. Now, packets are forwarded on the basis of labels, making this process faster than routing the packets with the IP addresses. MPLS also supports Traffic Engineering (TE). This refers to the process of selecting the best paths for data traffic in order to balance the traffic load between the different links. In a network with multiple paths, routing algorithms calculate the shortest one, and most of the times all traffic is directed through it, causing overload and packet drops, without distributing the packets in the other paths that the network offers and do not have any traffic. But this is not enough in order to provide the real time traffic the guarantees it needs. In fact, those mechanisms improve the network, but they do not make changes in how the traffic is treated. That is why Quality of Service (QoS) was developed. Quality of service is the ability to provide different priority to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow. Traffic is distributed into different classes and each of them is treated differently, according to its Service Level Agreement (SLA). Traffic with the highest priority will have the preference over lower classes, but this does not mean it will monopolize all the resources. In order to achieve this goal, a set policies are defined to control and alter how the traffic flows. Possibilities are endless, and it depends in how the network must be structured. By using those mechanisms it is possible to provide the necessary guarantees to the real-time traffic, distributing it between categories inside the network and offering the best service for both real time data and non real time data. Las Redes de Telecomunicaciones siempre han estado en expansión y han propiciado la aparición de nuevos servicios. Los viejos mecanismos para transportar paquetes se han quedado obsoletos debido a las exigencias de los nuevos servicios, que han comenzado a operar en tiempo real. El tráfico en tiempo real requiere de unas estrictas garantías de servicio. Cuando este tráfico se envía a través de la red, necesita disponer de suficientes recursos para evitar retrasos y pérdidas de información. Cuando se navega por la red y se solicitan páginas web, los datos viajan desde un servidor hasta el usuario. Si durante la transmisión se pierde algún paquete, éste se vuelve a mandar de nuevo. Para el usuario final, no importa si la página tarda uno o dos segundos más en cargar. Ahora bien, si el usuario está manteniendo una conversación usando algún programa de VoIP (como por ejemplo Skype) uno o dos segundos de retardo en la conversación podrían ser catastróficos, y ninguno de los interlocutores sería capaz de entender al otro. Para poder dar soporte a estos nuevos servicios, las redes deben evolucionar. Para este propósito se han concebido MPLS y QoS MPLS es un mecanismo de transporte de paquetes que se usa en redes de telecomunicaciones de alto rendimiento que dirige y transporta los datos de acuerdo a caminos preestablecidos. Ahora los paquetes se encaminan en función de unas etiquetas, lo cual hace que sea mucho más rápido que encaminar los paquetes usando las direcciones IP. MPLS también soporta Ingeniería de Tráfico (TE). Consiste en seleccionar los mejores caminos para el tráfico de datos con el objetivo de balancear la carga entre los diferentes enlaces. En una red con múltiples caminos, los algoritmos de enrutamiento actuales calculan el camino más corto, y muchas veces el tráfico se dirige sólo por éste, saturando el canal, mientras que otras rutas se quedan completamente desocupadas. Ahora bien, esto no es suficiente para ofrecer al tráfico en tiempo real las garantías que necesita. De hecho, estos mecanismos mejoran la red, pero no realizan cambios a la hora de tratar el tráfico. Por esto es por lo que se ha desarrollado el concepto de Calidad de Servicio (QoS). La calidad de servicio es la capacidad para ofrecer diferentes prioridades a las diferentes aplicaciones, usuarios o flujos de datos, y para garantizar un cierto nivel de rendimiento en un flujo de datos. El tráfico se distribuye en diferentes clases y cada una de ellas se trata de forma diferente, de acuerdo a las especificaciones que se indiquen en su Contrato de Tráfico (SLA). EL tráfico con mayor prioridad tendrá preferencia sobre el resto, pero esto no significa que acapare la totalidad de los recursos. Para poder alcanzar estos objetivos se definen una serie de políticas para controlar y alterar el comportamiento del tráfico. Las posibilidades son inmensas dependiendo de cómo se quiera estructurar la red. Usando estos mecanismos se pueden proporcionar las garantías necesarias al tráfico en tiempo real, distribuyéndolo en categorías dentro de la red y ofreciendo el mejor servicio posible tanto a los datos en tiempo real como a los que no lo son.

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Mixed criticality systems emerges as a suitable solution for dealing with the complexity, performance and costs of future embedded and dependable systems. However, this paradigm adds additional complexity to their development. This paper proposes an approach for dealing with this scenario that relies on hardware virtualization and Model-Driven Engineering (MDE). Hardware virtualization ensures isolation between subsystems with different criticality levels. MDE is intended to bridge the gap between design issues and partitioning concerns. MDE tooling will enhance the functional models by annotating partitioning and extra-functional properties. System partitioning and subsystems allocation will be generated with a high degree of automation. System configuration will be validated for ensuring that the resources assigned to a partition are sufficient for executing the allocated software components and that time requirements are met.

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The satellite remote sensing missions are essential for long-term research around the condition of the earth resources and environment. On the other hand, in recent years the application of microsatellites is of interest in many space programs for their less cost and response time. In microsatellite remote sensing missions there are tight interrelations between different requirements such as orbital altitude, revisit time, mission life and spatial resolution. Also, all of these requirements can affect the whole system level design characteristics. In this work, the remote sensing microsatellite sizing process is divided into three major design disciplines; a) orbit design, b) payload sizing and c) bus sizing. Finally, some specific design cases are investigated inside the design space for evaluating the effect of different design variables on the satellite total mass. Considering the results of the work, it is concluded that applying a systematic approach at the initial design phase of such projects provides a good insight to the not clearly seen interactions inside their highly extended design space

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Experimental software engineering includes several processes, the most representative being run experiments, run replications and synthesize the results of multiple replications. Of these processes, only the first is relatively well established in software engineering. Problems of information management and communication among researchers are one of the obstacles to progress in the replication and synthesis processes. Software engineering experimentation has expanded considerably over the last few years. This has brought with it the invention of experimental process support proposals. However, few of these proposals provide integral support, including replication and synthesis processes. Most of the proposals focus on experiment execution. This paper proposes an infrastructure providing integral support for the experimental research process, specializing in the replication and synthesis of a family of experiments. The research has been divided into stages or phases, whose transition milestones are marked by the attainment of their goals. Each goal exactly matches an artifact or product. Within each stage, we will adopt cycles of successive approximations (generateand- test cycles), where each approximation includes a diferent viewpoint or input. Each cycle will end with the product approval.

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The software engineering community has paid little attention to non-functional requirements, or quality attributes, compared with studies performed on capture, analysis and validation of functional requirements. This circumstance becomes more intense in the case of distributed applications. In these applications we have to take into account, besides the quality attributes such as correctness, robustness, extendibility, reusability, compatibility, efficiency, portability and ease of use, others like reliability, scalability, transparency, security, interoperability, concurrency, etc. In this work we will show how these last attributes are related to different abstractions that coexist in the problem domain. To achieve this goal, we have established a taxonomy of quality attributes of distributed applications and have determined the set of necessary services to support such attributes.

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El sector de la edificación es uno de los principales sectores económicos en España y, además, es un componente básico de la actividad económica y social, debido a su importante papel como generador de empleo, proveedor de bienes e incentivador del crecimiento. Curiosamente, es uno de los sectores con menos regulación y organización y que, además, está formado mayoritariamente por empresas de pequeña y mediana dimensión (pymes) que, por su menor capacidad, a menudo, se quedan detrás de las grandes empresas en términos de adopción de soluciones innovadoras. La complejidad en la gestión de toda la información relacionada con un proyecto de edificación ha puesto de manifiesto claras ineficiencias que se traducen en un gasto innecesario bastante representativo. La información y los conocimientos aprendidos rara vez son transmitidos de una fase a otra dentro del proyecto de edificación y, mucho menos, reutilizados en otros proyectos similares. De este modo, no sólo se produce un gasto innecesario, sino que incluso podemos encontrar información contradictoria y obsoleta y, por tanto, inútil para la toma de decisiones. A lo largo de los años, esta situación ha sido motivada por la propia configuración del sector, poniendo de manifiesto la necesidad de una solución que pudiera solventar este reto de gestión interorganizacional. Así, la cooperación interorganizacional se ha convertido en un factor clave para mejorar la competitividad de las organizaciones, típicamente pymes, que componen el sector de la edificación. La información es la piedra angular de cualquier proceso de negocio. Durante la última década, una amplia gama de industrias han experimentado importantes mejoras de productividad con la aplicación eficiente de las TIC, asociadas, principalmente, a incrementos en la velocidad de proceso de información y una mayor coherencia en la generación de datos, accesibilidad e intercambio de información. La aplicación eficaz de las TIC en el sector de la edificación requiere una combinación de aspectos estratégicos y tácticos, puesto que no sólo se trata de utilizar soluciones puntuales importadas de otros sectores para su aplicación en diferentes áreas, sino que se buscaría que la información multi-agente estuviera integrada y sea coherente para los proyectos de edificación. El sector de la construcción ha experimentado un descenso significativo en los últimos años en España y en Europa como resultado de la crisis financiera que comenzó en 2007. Esta disminución está acompañada de una baja penetración de las TIC en la interorganizacionales orientadas a los procesos de negocio. El descenso del mercado ha provocado una desaceleración en el sector de la construcción, donde sólo las pymes flexibles han sido capaces de mantener el ritmo a pesar de la especialización y la innovación en los servicios adaptados a las nuevas demandas del mercado. La industria de la edificación está muy fragmentada en comparación con otras industrias manufactureras. El alto grado de esta fragmentación está íntimamente relacionado con un impacto significativo en la productividad y el rendimiento. Muchos estudios de investigación han desarrollado y propuesto una serie de modelos de procesos integrados. Por desgracia, en la actualidad todavía no se está en condiciones para la formalización de cómo debe ser la comunicación y el intercambio de información durante el proceso de construcción. El paso del proceso secuencial tradicional a los procesos de interdependencia recíproca sin lugar a duda son una gran demanda asociada a la comunicación y el flujo de información en un proyecto de edificación. Recientemente se está poniendo mucho énfasis en los servicios para el hogar como un primer paso hacia esta mejora en innovación ya que la industria de los servicios digitales interactivos tiene un alto potencial para generar innovación y la ventaja estratégica para las empresas existentes. La multiplicidad de servicios para el hogar digital (HD) y los proveedores de servicios demandan, cada vez más, la aparición de una plataforma capaz de coordinar a todos los agentes del sector con el usuario final. En consecuencia, las estructuras organizacionales tienden a descentralizarse en busca de esa coordinación y, como respuesta a esta demanda, se plantea, también en este ámbito, el concepto de cooperación interorganizacional. Por lo tanto, ambos procesos de negocio -el asociado a la construcción y el asociado a la provisión de servicios del hogar digital, también considerado como la propia gestión de ese hogar digital o edificio, inteligente o no- deben de ser vistos en su conjunto mediante una plataforma tecnológica que les dé soporte y que pueda garantizar la agregación e integración de los diversos procesos, relacionados con la construcción y gestión, que se suceden durante el ciclo de vida de un edificio. Sobre esta idea y atendiendo a la evolución permanente de los sistemas de información en un entorno de interrelación y cooperación daría lugar a una aplicación del concepto de sistema de información interorganizacional (SIIO). El SIIO proporciona a las organizaciones la capacidad para mejorar los vínculos entre los socios comerciales a lo largo de la cadena de suministro, por lo que su importancia ha sido reconocida por organizaciones de diversos sectores. Sin embargo, la adopción de un SIIO en diferentes ámbitos ha demostrado ser complicada y con una alta dependencia de las características particulares de cada sector, siendo, en este momento, una línea de investigación abierta. Para contribuir a esta línea de investigación, este trabajo pretende recoger, partiendo de una revisión de la literatura relacionada, un enfoque en un modelo de adopción de un SIIO para el objeto concreto de esta investigación. El diseño de un SIIO está basado principalmente, en la identificación de las necesidades de información de cada uno de sus agentes participantes, de ahí la importancia en concretar un modelo de SIIO en el ámbito de este trabajo. Esta tesis doctoral presenta el modelo de plataforma virtual de la asociación entre diferentes agentes del sector de la edificación, el marco de las relaciones, los flujos de información correspondientes a diferentes procesos y la metodología que subyace tras el propio modelo, todo ello, con el objeto de contribuir a un modelo unificado que dé soporte tanto a los procesos relacionados con la construcción como con la gestión de servicios en el hogar digital y permitiendo cubrir los requisitos importantes que caracterizan este tipo de proyectos: flexibilidad, escalabilidad y robustez. El SIIO se ha convertido en una fuente de innovación y una herramienta estratégica que permite a las pymes obtener ventajas competitivas. Debido a la complejidad inherente de la adopción de un SIIO, esta investigación extiende el modelo teórico de adopción de un SIIO de Kurnia y Johnston (2000) con un modelo empírico para la caracterización de un SIIO. El modelo resultante tiene como objetivo fomentar la innovación de servicios en el sector mediante la identificación de los factores que influyen en la adopción de un SIIO por las pymes en el sector de la edificación como fuente de ventaja competitiva y de colaboración. Por tanto, esta tesis doctoral, proyectada sobre una investigación empírica, proporciona un enfoque para caracterizar un modelo de SIIO que permita dar soporte a la gestión integrada de los procesos de construcción y gestión de servicios para el hogar digital. La validez del modelo de SIIO propuesto, como fuente y soporte de ventajas competitivas, está íntimamente relacionada con la necesidad de intercambio de información rápido y fiable que demandan los agentes del sector para mejorar la gestión de su interrelación y cooperación con el fin de abordar proyectos más complejos en el sector de la edificación, relacionados con la implantación del hogar digital, y contribuyendo, así a favorecer el desarrollo de la sociedad de la información en el segmento residencial. ABSTRACT The building industry is the largest industry in the world. Land purchase, building design, construction, furnishing, building equipment, operations maintenance and the disposition of real estate have an unquestionable prominence not only at economic but also at social level. In Spain, the building sector is one of the main drivers of economy and also a basic component of economic activity and its role in generating employment, supply of goods or incentive for growth is crucial in the evolution of the economy. Surprisingly, it is one of the sectors with less regulation and organization. Another consistent problem is that, in this sector, the majority of companies are small and medium (SMEs), and often behind large firms in terms of their adoption of innovative solutions. The complexity of managing all information related to this industry has lead to a waste of money and time. The information and knowledge gathered is frequently stored in multiple locations, involving the work of thousands of people, and is rarely transferred on to the next phase. This approach is inconsistent and makes that incorrect information is used for decisions. This situation needs a viable solution for interorganizational information management. So, interorganizational co-operation has become a key factor for organization competitiveness within the building sector. Information is the cornerstone of any business process. Therefore, information and communication technologies (ICT) offer a means to change the way business is conducted. During the last decade, significant productivity improvements were experienced by a wide range of industries with ICT implementation. ICT has provided great advantages in speed of operation, consistency of data generation, accessibility and exchange of information. The wasted money resulting from reentering information, errors and omissions caused through poor decisions and actions, and the delays caused while waiting for information, represent a significant percentage of the global benefits. The effective application of ICT in building construction sector requires a combination of strategic and tactical developments. The building sector has experienced a significant decline in recent years in Spain and in Europe as a result of the financial crisis that began in 2007. This drop goes hand in hand with a low penetration of ICT in inter-organizational-oriented business processes. The market decrease has caused a slowdown in the building sector, where only flexible SMEs have been able to keep the pace though specialization and innovation in services adapted to new market demands. The building industry is highly fragmented compared with other manufacturing industries. This fragmentation has a significant negative impact on productivity and performance. Many research studies have developed and proposed a number of integrated process models. Unfortunately, these studies do not suggest how communication and information exchange within the construction process can be achieved, without duplication or lost in quality. A change from the traditional sequential process to reciprocal interdependency processes would increase the demand on communication and information flow over the edification project. Focusing on home services, the digital interactive service industry has the potential to generate innovation and strategic advantage for existing business. Multiplicity of broadband home services (BHS) and suppliers suggest the need for a figure able to coordinate all the agents in sector with the final user. Consequently, organizational structures tend to be decentralized. Responding to this fact, the concept of interorganizational co-operation also is raising in the residential market. Therefore, both of these business processes, building and home service supply, must be complemented with a technological platform that supports these processes and guarantees the aggregation and integration of the several services over building lifecycle. In this context of a technological platform and the permanent evolution of information systems is where the relevance of the concept of inter-organizational information system (IOIS) emerges. IOIS improves linkages between trading partners along the supply chain. However, IOIS adoption has proved to be difficult and not fully accomplished yet. This research reviews the literature in order to focus a model of IOIS adoption. This PhD Thesis presents a model of virtual association, a framework of the relationships, an identification of the information requirements and the corresponding information flows, using the multi-agent system approach. IOIS has become a source of innovation and a strategic tool for SMEs to obtain competitive advantage. Because of the inherent complexity of IOIS adoption, this research extends Kurnia and Johnston’s (2000) theoretical model of IOIS adoption with an empirical model of IOIS characterization. The resultant model aims to foster further service innovation in the sector by identifying the factors influencing IOIS adoption by the SMEs in the building sector as a source of competitive and collaborative advantage. Therefore, this PhD Thesis characterizes an IOIS model to support integrated management of building processes and home services. IOIS validity, as source and holder of competitive advantages, is related to the need for reliable information interchanges to improve interrelationship management. The final goal is to favor tracking of more complex projects in building sector and to contribute to consolidation of the information society through the provision of broadband home services and home automation.

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In recent years, the increasing sophistication of embedded multimedia systems and wireless communication technologies has promoted a widespread utilization of video streaming applications. It has been reported in 2013 that youngsters, aged between 13 and 24, spend around 16.7 hours a week watching online video through social media, business websites, and video streaming sites. Video applications have already been blended into people daily life. Traditionally, video streaming research has focused on performance improvement, namely throughput increase and response time reduction. However, most mobile devices are battery-powered, a technology that grows at a much slower pace than either multimedia or hardware developments. Since battery developments cannot satisfy expanding power demand of mobile devices, research interests on video applications technology has attracted more attention to achieve energy-efficient designs. How to efficiently use the limited battery energy budget becomes a major research challenge. In addition, next generation video standards impel to diversification and personalization. Therefore, it is desirable to have mechanisms to implement energy optimizations with greater flexibility and scalability. In this context, the main goal of this dissertation is to find an energy management and optimization mechanism to reduce the energy consumption of video decoders based on the idea of functional-oriented reconfiguration. System battery life is prolonged as the result of a trade-off between energy consumption and video quality. Functional-oriented reconfiguration takes advantage of the similarities among standards to build video decoders reconnecting existing functional units. If a feedback channel from the decoder to the encoder is available, the former can signal the latter changes in either the encoding parameters or the encoding algorithms for energy-saving adaption. The proposed energy optimization and management mechanism is carried out at the decoder end. This mechanism consists of an energy-aware manager, implemented as an additional block of the reconfiguration engine, an energy estimator, integrated into the decoder, and, if available, a feedback channel connected to the encoder end. The energy-aware manager checks the battery level, selects the new decoder description and signals to build a new decoder to the reconfiguration engine. It is worth noting that the analysis of the energy consumption is fundamental for the success of the energy management and optimization mechanism. In this thesis, an energy estimation method driven by platform event monitoring is proposed. In addition, an event filter is suggested to automate the selection of the most appropriate events that affect the energy consumption. At last, a detailed study on the influence of the training data on the model accuracy is presented. The modeling methodology of the energy estimator has been evaluated on different underlying platforms, single-core and multi-core, with different characteristics of workload. All the results show a good accuracy and low on-line computation overhead. The required modifications on the reconfiguration engine to implement the energy-aware manager have been assessed under different scenarios. The results indicate a possibility to lengthen the battery lifetime of the system in two different use-cases.

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La creciente complejidad, heterogeneidad y dinamismo inherente a las redes de telecomunicaciones, los sistemas distribuidos y los servicios avanzados de información y comunicación emergentes, así como el incremento de su criticidad e importancia estratégica, requieren la adopción de tecnologías cada vez más sofisticadas para su gestión, su coordinación y su integración por parte de los operadores de red, los proveedores de servicio y las empresas, como usuarios finales de los mismos, con el fin de garantizar niveles adecuados de funcionalidad, rendimiento y fiabilidad. Las estrategias de gestión adoptadas tradicionalmente adolecen de seguir modelos excesivamente estáticos y centralizados, con un elevado componente de supervisión y difícilmente escalables. La acuciante necesidad por flexibilizar esta gestión y hacerla a la vez más escalable y robusta, ha provocado en los últimos años un considerable interés por desarrollar nuevos paradigmas basados en modelos jerárquicos y distribuidos, como evolución natural de los primeros modelos jerárquicos débilmente distribuidos que sucedieron al paradigma centralizado. Se crean así nuevos modelos como son los basados en Gestión por Delegación, en el paradigma de código móvil, en las tecnologías de objetos distribuidos y en los servicios web. Estas alternativas se han mostrado enormemente robustas, flexibles y escalables frente a las estrategias tradicionales de gestión, pero continúan sin resolver aún muchos problemas. Las líneas actuales de investigación parten del hecho de que muchos problemas de robustez, escalabilidad y flexibilidad continúan sin ser resueltos por el paradigma jerárquico-distribuido, y abogan por la migración hacia un paradigma cooperativo fuertemente distribuido. Estas líneas tienen su germen en la Inteligencia Artificial Distribuida (DAI) y, más concretamente, en el paradigma de agentes autónomos y en los Sistemas Multi-agente (MAS). Todas ellas se perfilan en torno a un conjunto de objetivos que pueden resumirse en alcanzar un mayor grado de autonomía en la funcionalidad de la gestión y una mayor capacidad de autoconfiguración que resuelva los problemas de escalabilidad y la necesidad de supervisión presentes en los sistemas actuales, evolucionar hacia técnicas de control fuertemente distribuido y cooperativo guiado por la meta y dotar de una mayor riqueza semántica a los modelos de información. Cada vez más investigadores están empezando a utilizar agentes para la gestión de redes y sistemas distribuidos. Sin embargo, los límites establecidos en sus trabajos entre agentes móviles (que siguen el paradigma de código móvil) y agentes autónomos (que realmente siguen el paradigma cooperativo) resultan difusos. Muchos de estos trabajos se centran en la utilización de agentes móviles, lo cual, al igual que ocurría con las técnicas de código móvil comentadas anteriormente, les permite dotar de un mayor componente dinámico al concepto tradicional de Gestión por Delegación. Con ello se consigue flexibilizar la gestión, distribuir la lógica de gestión cerca de los datos y distribuir el control. Sin embargo se permanece en el paradigma jerárquico distribuido. Si bien continúa sin definirse aún una arquitectura de gestión fiel al paradigma cooperativo fuertemente distribuido, estas líneas de investigación han puesto de manifiesto serios problemas de adecuación en los modelos de información, comunicación y organizativo de las arquitecturas de gestión existentes. En este contexto, la tesis presenta un modelo de arquitectura para gestión holónica de sistemas y servicios distribuidos mediante sociedades de agentes autónomos, cuyos objetivos fundamentales son el incremento del grado de automatización asociado a las tareas de gestión, el aumento de la escalabilidad de las soluciones de gestión, soporte para delegación tanto por dominios como por macro-tareas, y un alto grado de interoperabilidad en entornos abiertos. A partir de estos objetivos se ha desarrollado un modelo de información formal de tipo semántico, basado en lógica descriptiva que permite un mayor grado de automatización en la gestión en base a la utilización de agentes autónomos racionales, capaces de razonar, inferir e integrar de forma dinámica conocimiento y servicios conceptualizados mediante el modelo CIM y formalizados a nivel semántico mediante lógica descriptiva. El modelo de información incluye además un “mapping” a nivel de meta-modelo de CIM al lenguaje de especificación de ontologías OWL, que supone un significativo avance en el área de la representación y el intercambio basado en XML de modelos y meta-información. A nivel de interacción, el modelo aporta un lenguaje de especificación formal de conversaciones entre agentes basado en la teoría de actos ilocucionales y aporta una semántica operacional para dicho lenguaje que facilita la labor de verificación de propiedades formales asociadas al protocolo de interacción. Se ha desarrollado también un modelo de organización holónico y orientado a roles cuyas principales características están alineadas con las demandadas por los servicios distribuidos emergentes e incluyen la ausencia de control central, capacidades de reestructuración dinámica, capacidades de cooperación, y facilidades de adaptación a diferentes culturas organizativas. El modelo incluye un submodelo normativo adecuado al carácter autónomo de los holones de gestión y basado en las lógicas modales deontológica y de acción.---ABSTRACT---The growing complexity, heterogeneity and dynamism inherent in telecommunications networks, distributed systems and the emerging advanced information and communication services, as well as their increased criticality and strategic importance, calls for the adoption of increasingly more sophisticated technologies for their management, coordination and integration by network operators, service providers and end-user companies to assure adequate levels of functionality, performance and reliability. The management strategies adopted traditionally follow models that are too static and centralised, have a high supervision component and are difficult to scale. The pressing need to flexibilise management and, at the same time, make it more scalable and robust recently led to a lot of interest in developing new paradigms based on hierarchical and distributed models, as a natural evolution from the first weakly distributed hierarchical models that succeeded the centralised paradigm. Thus new models based on management by delegation, the mobile code paradigm, distributed objects and web services came into being. These alternatives have turned out to be enormously robust, flexible and scalable as compared with the traditional management strategies. However, many problems still remain to be solved. Current research lines assume that the distributed hierarchical paradigm has as yet failed to solve many of the problems related to robustness, scalability and flexibility and advocate migration towards a strongly distributed cooperative paradigm. These lines of research were spawned by Distributed Artificial Intelligence (DAI) and, specifically, the autonomous agent paradigm and Multi-Agent Systems (MAS). They all revolve around a series of objectives, which can be summarised as achieving greater management functionality autonomy and a greater self-configuration capability, which solves the problems of scalability and the need for supervision that plague current systems, evolving towards strongly distributed and goal-driven cooperative control techniques and semantically enhancing information models. More and more researchers are starting to use agents for network and distributed systems management. However, the boundaries established in their work between mobile agents (that follow the mobile code paradigm) and autonomous agents (that really follow the cooperative paradigm) are fuzzy. Many of these approximations focus on the use of mobile agents, which, as was the case with the above-mentioned mobile code techniques, means that they can inject more dynamism into the traditional concept of management by delegation. Accordingly, they are able to flexibilise management, distribute management logic about data and distribute control. However, they remain within the distributed hierarchical paradigm. While a management architecture faithful to the strongly distributed cooperative paradigm has yet to be defined, these lines of research have revealed that the information, communication and organisation models of existing management architectures are far from adequate. In this context, this dissertation presents an architectural model for the holonic management of distributed systems and services through autonomous agent societies. The main objectives of this model are to raise the level of management task automation, increase the scalability of management solutions, provide support for delegation by both domains and macro-tasks and achieve a high level of interoperability in open environments. Bearing in mind these objectives, a descriptive logic-based formal semantic information model has been developed, which increases management automation by using rational autonomous agents capable of reasoning, inferring and dynamically integrating knowledge and services conceptualised by means of the CIM model and formalised at the semantic level by means of descriptive logic. The information model also includes a mapping, at the CIM metamodel level, to the OWL ontology specification language, which amounts to a significant advance in the field of XML-based model and metainformation representation and exchange. At the interaction level, the model introduces a formal specification language (ACSL) of conversations between agents based on speech act theory and contributes an operational semantics for this language that eases the task of verifying formal properties associated with the interaction protocol. A role-oriented holonic organisational model has also been developed, whose main features meet the requirements demanded by emerging distributed services, including no centralised control, dynamic restructuring capabilities, cooperative skills and facilities for adaptation to different organisational cultures. The model includes a normative submodel adapted to management holon autonomy and based on the deontic and action modal logics.

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It is essential to remotely and continuously monitor the movements of individuals in many social areas, for example, taking care of aging people, physical therapy, athletic training etc. Many methods have been used, such as video record, motion analysis or sensor-based methods. Due to the limitations in remote communication, power consumption, portability and so on, most of them are not able to fulfill the requirements. The development of wearable technology and cloud computing provides a new efficient way to achieve this goal. This paper presents an intelligent human movement monitoring system based on a smartwatch, an Android smartphone and a distributed data management engine. This system includes advantages of wide adaptability, remote and long-term monitoring capacity, high portability and flexibility. The structure of the system and its principle are introduced. Four experiments are designed to prove the feasibility of the system. The results of the experiments demonstrate the system is able to detect different actions of individuals with adequate accuracy.

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A major challenge in the engineering of complex and critical systems is the management of change, both in the system and in its operational environment. Due to the growing of complexity in systems, new approaches on autonomy must be able to detect critical changes and avoid their progress towards undesirable states. We are searching for methods to build systems that can tune the adaptability protocols. New mechanisms that use system-wellness requirements to reduce the influence of the outer domain and transfer the control of uncertainly to the inner one. Under the view of cognitive systems, biological emotions suggests a strategy to configure value-based systems to use semantic self-representations of the state. A method inspired by emotion theories to causally connect to the inner domain of the system and its objectives of wellness, focusing on dynamically adapting the system to avoid the progress of critical states. This method shall endow the system with a transversal mechanism to monitor its inner processes, detecting critical states and managing its adaptivity in order to maintain the wellness goals. The paper describes the current vision produced by this work-in-progress.