The purpose of this paper was two-fold. The first was to investigate the impact of conflict as a mediator in the relationship between distribution and team performance. The second was to examine how that relationship was affected by virtuality. Four-member teams of different distributions (partially distributed, fully distributed, and fully collocated) and different virtuality conditions (videoconferencing, teleconferencing, and chat) played a team-oriented game. Significant results were found only in the videoconferencing condition, in which both distribution and task conflict had a negative impact on team performance, but task conflict did not mediate the relationship between distribution and team performance. Further research investigating how virtuality impacts distributed teams in needed.

Esta tese propõe um novo método para a avaliação de desempenho de protocolos de sincronização otimistas adotados em programas de simulação distribuída. A utilização do método proposto é atrativa principalmente por permitir um usuário de simulação distribuída otimista optar pelo protocolo que mais se adapta às suas necessidades, sem ter que implementá-lo. O método de avaliação tem o modelo de um processo lógico Time Warp básico como núcleo, levando em consideração as características tanto da aplicação como da plataforma de hardware/software utilizada (o ambiente ALPHA/Sim é utilizado para a modelagem e simulação através de Redes de Petri). As características mais relevantes do protocolo Time Warp básico e suas variações são identificadas, a partir de uma nova taxonomia hierárquica proposta nesta tese, aliada a uma revisão bibliográfica ampla e detalhada. Além disso, domínios de plugins foram identificados, permitindo uma extensão (ou modificação) rápida e direta do modelo do Time Warp básico proposto. Esta tese também contribui apresentando resultados da avaliação de desempenho do protocolo Time Warp básico e do protocolo probabilístico PDSP. / This thesis proposes a novel method for the performance evaluation of optimistic synchronisation protocols adopted in distributed simulation programs. The use of the proposed method is attractive mainly for allowing an optimistic distributed simulation user to choose the protocol that best fits his needs, without having to implement it. The evaluation method has the model for a basic Time Warp logical process as its kernel, that takes into consideration the features of both the application and the hardware/software platform adopted (the ALPHA/Sim environment is used for modelling and simulation purposes through Petri Nets). The more relevant features of the basic Time Warp protocol and its variants are identified by using a new hierarchical taxonomy proposed in this thesis together with a wide and detailed literature survey. Furthermore, plugin domains could also been identified, allowing a quick and straightforward extension (or modification) of the basic Time Warp model proposed. This thesis also contributes by presenting performance evaluation results for both the basic Time Warp protocol and the PDSP probabilistic protocol.

Esta tese propõe um novo método para a avaliação de desempenho de protocolos de sincronização otimistas adotados em programas de simulação distribuída. A utilização do método proposto é atrativa principalmente por permitir um usuário de simulação distribuída otimista optar pelo protocolo que mais se adapta às suas necessidades, sem ter que implementá-lo. O método de avaliação tem o modelo de um processo lógico Time Warp básico como núcleo, levando em consideração as características tanto da aplicação como da plataforma de hardware/software utilizada (o ambiente ALPHA/Sim é utilizado para a modelagem e simulação através de Redes de Petri). As características mais relevantes do protocolo Time Warp básico e suas variações são identificadas, a partir de uma nova taxonomia hierárquica proposta nesta tese, aliada a uma revisão bibliográfica ampla e detalhada. Além disso, domínios de plugins foram identificados, permitindo uma extensão (ou modificação) rápida e direta do modelo do Time Warp básico proposto. Esta tese também contribui apresentando resultados da avaliação de desempenho do protocolo Time Warp básico e do protocolo probabilístico PDSP. / This thesis proposes a novel method for the performance evaluation of optimistic synchronisation protocols adopted in distributed simulation programs. The use of the proposed method is attractive mainly for allowing an optimistic distributed simulation user to choose the protocol that best fits his needs, without having to implement it. The evaluation method has the model for a basic Time Warp logical process as its kernel, that takes into consideration the features of both the application and the hardware/software platform adopted (the ALPHA/Sim environment is used for modelling and simulation purposes through Petri Nets). The more relevant features of the basic Time Warp protocol and its variants are identified by using a new hierarchical taxonomy proposed in this thesis together with a wide and detailed literature survey. Furthermore, plugin domains could also been identified, allowing a quick and straightforward extension (or modification) of the basic Time Warp model proposed. This thesis also contributes by presenting performance evaluation results for both the basic Time Warp protocol and the PDSP probabilistic protocol.

Nous proposons dans cette thèse, différents outils de réglage de tension et de gestion de la puissance réactive en fonction des conditions de raccordement des éoliennes au réseau électrique. Trois cas figure sont étudiés : raccordement direct sur un poste source de distribution, raccordement des éoliennes réparties dans un réseau de distribution et raccordement d’un ensemble de parcs éoliens au réseau de transport.Un algorithme de réglage basé sur l’asservissement de la puissance réactive est proposé pour le raccordement direct d'un parc sur un poste source. Un réglage coordonné de tension en présence de régleur en charge est proposé (D-RCT) pour le raccordement des éoliennes reparties dans un réseau de distribution. On propose aussi une version plus décentralisée du réglage coordonné (D2-RCT) qui pourrait être implantée sous forme de système multi-agents intelligents (SMA). Un system de control multi-niveaux est proposé pour le raccordement d’un ensemble de parcs éoliens au réseau de transport. Il permet de répondre de manière optimale à une demande puissance réactive envoyée par le gestionnaire du réseau de transport. Les différents types de réglages proposés sont basés sur des algorithmes d’optimisation multi-objectifs. Afin de valider en temps réel le bon fonctionnement des stratégies de réglages développées ainsi que leurs modes de communication, une implantation expérimentale sous simulateur temps réel RT-Lab a été effectuée. Enfin, les résultats des simulations montrent l’amélioration de l’intégration de la production décentralisée dans les réseaux électriques / In this PhD dissertation, we propose various voltage and reactive power regulation algorithms for different connection types of the wind farm to the power network. Three connection types are considered here: a wind farm connected directly to the distribution network, dispersed wind turbines connected to the distribution network and a set of wind farms connected to the transmission system.A closed loop controller (Wind Farm Controller) is proposed in case of a directly connected wind farm to the distribution network.A coordinated voltage control in the presence of on load tap changer (D-CVC) is proposed in case of dispersed wind turbines connected to the distribution network. We also propose a more decentralized version of D-CVC named D2-CVC; this version can be also implemented under multi-agent system (MAS).A multi-level control system is proposed in case of a set of wind farms connected to the transmission system. It allows the wind farms to optimally participate at reactive power balancing in transmission network. All the proposed voltage algorithms are based on a multi-objective optimization function. The experimental implementation of these regulation algorithms is run under RT-Lab real-time simulator. It allows validating their real-time operation and their communication modes before the implementation on a real site.The results of the current thesis show the improvement of distributed generation integration in the power system network