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A mobile ad hoc network consists of certain nodes that communicate only through wireless medium and can move arbitrarily. The key feature of a mobile ad hoc network is the mobility of the nodes. Because of the mobility, communication links form and disappear as nodes come into and go out of each other's communica- tion range. Mobile ad hoc networks are particularly useful in situations like disaster recovery and search, military operations, etc. Research on mobile ad hoc networks has drawn a huge amount of attention recently. The main challenges for mobile ad hoc networks are the sparse resources and frequent mobility. Most of the research work has been focused on the MAC and routing layer. In this work, we focus on distributed services for mobile ad hoc networks. These services will provide some fundamental functions in developing various applications for mobile ad hoc networks. In particular, we focus on the clock synchronization, connected dominating set, and k-mutual exclusion problems in mobile ad hoc networks.

The purpose of this thesis was to find approaches solving major performance and scalability issues for Topic Maps-related data access and the merging process. Especially regarding the management of multiple, heterogeneous topic maps with different sizes and structures. Hence the scope of the research was mainly focused on the Maiana web application with its underlying MaJorToM and TMQL4J back-end.

The use of distributed systems, involving multiple components, has become a common industry practice. However, modeling the behaviour of such systems is a challenge, especially when the behavior consists of several collaborations of different parties, each involving possibly several starting (input) and ending (output) events of the involved components. Furthermore, the global behavior should be described as a composition of several sub-behaviours, in the following called collaborations, and each collaboration may be further decomposed into several sub-collaborations. We assume that the performance of the elementary sub-collaborations is known, and that the performance of the global behavior should be determined from the performance of the contained elementary collaborations and the form of the composition. A collaboration, in this thesis, is characterized by a partial order of input and output events, and the performance of the collaboration is defined by the minimum delays required for a given output event with respect to an input event. This is a generalization of the semantics of UML Activities, where all input events are assumed to occur at the same time, and all output events occur at the same time. We give a semantic definition of the dynamic behavior of composed collaborations using the composition operators for control flow from UML Activity diagrams, in terms of partial order relationships among the involved input and output events. Based on these semantics, we provide formulas for calculating the performance of composed collaborations in terms of the performance of the sub-collaborations, where each delay is characterized by (a) a fixed value, (b) a range of values, and (c) a distribution (in the case of stochastic behaviours). We also propose approximations for the case of stochastic behavior with Normal distributions, and discuss the expected errors that may be introduced due to ignoring of shared resources or possible dependencies in the case of stochastic behaviours. A tool has been developed for evaluating the performance of complex collaborations, and examples and case studies are discussed to illustrate the applicability of the performance analysis and the visual notation which we introduced for representing the partial-order relationships of the input and output events.

The use of distributed systems, involving multiple components, has become a common industry practice. However, modeling the behaviour of such systems is a challenge, especially when the behavior consists of several collaborations of different parties, each involving possibly several starting (input) and ending (output) events of the involved components. Furthermore, the global behavior should be described as a composition of several sub-behaviours, in the following called collaborations, and each collaboration may be further decomposed into several sub-collaborations. We assume that the performance of the elementary sub-collaborations is known, and that the performance of the global behavior should be determined from the performance of the contained elementary collaborations and the form of the composition. A collaboration, in this thesis, is characterized by a partial order of input and output events, and the performance of the collaboration is defined by the minimum delays required for a given output event with respect to an input event. This is a generalization of the semantics of UML Activities, where all input events are assumed to occur at the same time, and all output events occur at the same time. We give a semantic definition of the dynamic behavior of composed collaborations using the composition operators for control flow from UML Activity diagrams, in terms of partial order relationships among the involved input and output events. Based on these semantics, we provide formulas for calculating the performance of composed collaborations in terms of the performance of the sub-collaborations, where each delay is characterized by (a) a fixed value, (b) a range of values, and (c) a distribution (in the case of stochastic behaviours). We also propose approximations for the case of stochastic behavior with Normal distributions, and discuss the expected errors that may be introduced due to ignoring of shared resources or possible dependencies in the case of stochastic behaviours. A tool has been developed for evaluating the performance of complex collaborations, and examples and case studies are discussed to illustrate the applicability of the performance analysis and the visual notation which we introduced for representing the partial-order relationships of the input and output events.

[ES] Los sistemas de salud actuales están viendo cómo la cantidad de pacientes a atender y de servicios diferentes que han de prestar, es cada vez mayor, por lo que se cuestiona si serán sostenibles a largo plazo. Uno de los factores importantes de este aumento es el envejecimiento de la población, lo que implica un mayor número de pacientes crónicos y de personas dependientes. Al mismo tiempo, se genera la necesidad de abordar soluciones de prevención sobre la población general. Para hacer frente a estos problemas, se está recurriendo a la aplicación de las TIC en el ámbito de la salud, son los llamados sistemas de eSalud. En el desarrollo de sistemas de eSalud es necesario tener en cuenta que deben trabajar en entornos altamente heterogéneos y cambiantes. Además, han de ser capaces de adaptarse a las nuevas necesidades demandadas por la población, todo ello sin reducir la calidad de los servicios ya prestados y sin disparar los costes del sistema. Al desarrollar un sistema software, el modelo de arquitectura elegido marca qué características se van a potenciar. El paradigma de Arquitectura Orientada a Servicios (SOA) presenta entre sus principales beneficios una alta flexibilidad, reducción de costes y desarrollo rápido, así como permite la escalabilidad de sistemas. Por lo que puede ser un buen candidato a la hora de crear sistemas de eSalud. Existen diferentes formas de construir una arquitectura SOA, atendiendo a cómo se componen sus servicios y a cómo se aplican las directrices SOA. En esta tesis se propone el uso del paradigma de coreografía de procesos, siendo éste un modelo en el que se busca construir la arquitectura del sistema desde el punto de vista de los procesos de negocio de la organización. Este paradigma trabaja desde el concepto de un proceso único definido de forma distribuida, empleando coreografía de servicios para la composición. Es decir, no existe un elemento que centralice la toma de decisiones, donde cada servicio es consciente de qué debe realizar y cómo interactuar con el resto. En la coreografía de procesos se prioriza la eficiencia del sistema, aumentando el acoplamiento entre servicios, lo que puede reducir la flexibilidad del sistema SOA. Pero genera un sistema con mayor rendimiento y con una mejor alineación con los procesos de negocio. Además, la coreografía es más robusta que otros mecanismos de composición y ayuda con la integración de sistemas entre empresas. El objetivo de esta tesis es validar si el paradigma de coreografía de procesos es aplicable al desarrollo de sistemas de eSalud. Para ello se ha realizado la aplicación de este paradigma en tres escenarios de eSalud diferentes. En el primero de los escenarios, se creó un sistema para integrar y evaluar un dispositivo tecnológico puntero, las Google Glass. Esto demostró que se puede crear un sistema de eSalud basado en coreografía de procesos que integre dispositivos tecnológicos complejos. En el segundo de los escenarios, se validó el paradigma en un entorno real, creando un sistema distribuido de ejecución de modelos híbridos para la predicción y detección de diabetes tipo 2. El sistema permitió construir servicios para la ejecución de los modelos híbridos, integrando motores estadísticos externos y sistemas de terceros de acceso a datos clínicos. De esta forma se validó que la coreografía de procesos ayuda a la integración con sistemas externos, permitiendo un desarrollo rápido y la creación de sistemas distribuidos. En el tercero de los escenarios, se aplica el paradigma orientado al modelo de IoT integrando sensores portables para crear un sistema de eSalud. El sistema desarrollado integra un kit de sensores de eSalud para el seguimiento y monitorización remota de pacientes, comparando su rendimiento en un ordenador y en una Raspberry Pi. El resultado refrenda la hipótesis de que la coreografía de procesos permite aplicarse para crear fácilmente sistemas de eSalud orientados a IoT e integrar sensores portables de este ámbito. / [CA] Els sistemes de salut actuals estan veient com la quantitat de pacients a atendre i de servicis diferents que han de prestar, és cada vegada major, per la qual cosa es qüestiona si seran sostenibles a llarg termini. Un dels factors importants d'aquest augment és l'envelliment de la població, la qual cosa implica un major nombre de pacients crònics i de persones dependents. Al mateix temps, es genera la necessitat d'abordar solucions de prevenció sobre la població general. Per a fer front a aquests problemes, s'està recorrent a l'aplicació de les TIC en l'àmbit de la salut, són els cridats sistemes d'eSalut. En el desenvolupament de sistemes d'eSalut és necessari tindre en compte que han de treballar en entorns altament heterogenis i canviants. A més, han de ser capaços d'adaptar-se a les noves necessitats demandades per la població, tot això sense reduir la qualitat dels servicis ja prestats i sense disparar els costos del sistema. En desenvolupar un sistema programari, el model d'arquitectura triat marca quines característiques es potenciaran. El paradigma d'Arquitectura Orientada a Servicis (SOA) presenta entre els seus principals beneficis una alta flexibilitat, reducció de costos i desenrotllament ràpid, així com permet l'escalabilitat de sistemes. Pel que pot ser un bon candidat a l'hora de crear sistemes d'eSalut. Hi ha diferents formes de construir una arquitectura SOA, atenent a com es componen els seus servicis i a com s'apliquen les directrius SOA. En esta tesi es proposa l'ús del paradigma de coreografia de processos, sent aquest un model en el qual es busca construir l'arquitectura del sistema des del punt de vista dels processos de negoci de l'organització. Este paradigma treballa des del concepte d'un procés únic definit de forma distribuïda, emprant coreografia de servicis per a la composició. És a dir, no hi ha un element que centralitze la presa de decisions, on cada servici és conscient de què ha de realitzar i com interactuar amb la resta. En la coreografia de processos es prioritza l'eficiència del sistema, augmentant l'adaptament entre servicis, la qual cosa pot reduir la flexibilitat del sistema SOA. Però genera un sistema amb major rendiment i amb una millor alineació amb els processos de negoci. A més, la coreografia és més robusta que altres mecanismes de composició i ajuda amb la integració de sistemes entre empreses. L'objectiu d'aquesta tesi és validar si el paradigma de coreografia de processos és aplicable al desenrotllament de sistemes d'eSalut. Per a això s'ha realitzat l'aplicació d'aquest paradigma en tres escenaris d'eSalut diferents. En el primer dels escenaris, es va crear un sistema per a integrar i avaluar un dispositiu tecnològic punter, les Google Glass. Açò va demostrar que es pot crear un sistema d'eSalut basat en coreografia de processos que integre dispositius tecnològics complexos. En el segon dels escenaris, es va validar el paradigma en un entorn real, creant un sistema distribuït d'execució de models híbrids per a la predicció i detecció de diabetis tipus 2. El sistema va permetre construir servicis per a l'execució dels models híbrids, integrant motors estadístics externs i sistemes de tercers d'accés a dades clíniques. D'aquesta manera es va validar que la coreografia de processos ajuda amb la integració amb sistemes externs, permetent un desenrotllament ràpid i la creació de sistemes distribuïts. En el tercer dels escenaris, s'aplica el paradigma orientat al model d'IoT integrant sensors portables per a crear un sistema d'eSalut. El sistema desenrotllat integra un kit de sensors d'eSalut per al seguiment i monitorització remota de pacients, comparant el seu rendiment en un ordinador i en una Raspberry Pi. El resultat referenda la hipòtesi que la coreografia de processos permet aplicar-se per a crear fàcilment sistemes d'eSalut orientats a IoT i integrar sensors portables d'este àmbit. / [EN] Today's health systems are seeing an increasing number of patients to be cared for, as well as different services to be provided, raising questions as to whether they will be sustainable in the long term. One of the critical factors in this increase is the ageing of the population, which implies a more significant number of chronic patients and dependents. At the same time, there is a need to address prevention solutions in the general population. To address these problems, the application of ICTs in the health field, the so-called eHealth systems, is being used. In the development of eHealth systems, it is necessary to consider that they have to work in highly heterogeneous and changing environments. Moreover, they must be able to adapt to the new needs demanded by the population, without reducing the quality of the services already provided and without increasing the costs of the system. When developing a software system, the architecture model chosen determines which characteristics are to be enhanced. The Service Oriented Architecture (SOA) paradigm has among its main benefits high flexibility, cost reduction and rapid development, as well as allowing the scalability of systems. Therefore, it can be a good candidate when creating eHealth systems. There are different ways to build an SOA architecture, depending on how its services are composed and how SOA guidelines are applied. This thesis proposes the use of the process choreography paradigm, which is a model that seeks to build the architecture of the system from the point of view of the organisation's business processes. This paradigm works from the concept of a single process defined in a distributed way, using service choreography for the composition. In other words, there is no centralised decision-making element, where each service is aware of what it must do and how to interact with the rest. Process choreography prioritises system efficiency by increasing coupling between services, which can reduce the flexibility of the SOA system. But it generates a system with higher performance and better alignment with business processes. In addition, choreography is more robust than other composition mechanisms and helps with cross-company system integration. The aim of this thesis is to validate whether the process choreography paradigm is applicable to the development of eHealth systems. To this end, the application of this paradigm has been carried out in three different eHealth scenarios. In the first scenario, a system was created to integrate and evaluate a cutting-edge technological device, Google Glass. This demonstrated that it is possible to create an eHealth system based on process choreography that integrates complex technological devices. In the second scenario, the paradigm was validated in a real environment, creating a distributed hybrid model execution system for the prediction and detection of type 2 diabetes. The system allowed building services for hybrid model execution, integrating external statistical engines and third-party services to access clinical data. This scenario validated that the process choreography aids integration with external systems, enabling rapid development and the creation of distributed systems. In the third scenario, the paradigm is applied to the IoT model by integrating wearable sensors to create an eHealth system. The developed system integrates an eHealth sensor kit for remote patient tracking and monitoring, comparing its performance on a computer and a Raspberry Pi. The result supports the hypothesis that process choreography can be applied to easily create IoT-oriented eHealth systems and integrate IoT wearable sensors. / Bayo Montón, JL. (2023). Propuesta de uso del paradigma de coreografía de procesos para crear sistemas de eSalud en entornos heterogéneos [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/192822