In Canada, access to magnetic resonance imaging (MRI) examination is limited with an outcome of long patient waiting time. It is reported that the current median waiting time for MRI examination in Saskatoon is almost double the target for waiting time, which may aggravate the disease. This research is towards reducing the waiting time of patients for MRI examination in Canada by applying an improved management. As a first step of this effort, a comprehensive model of MRI booking and serving system is needed. The city of Saskatoon was taken as an example and the MRI booking and serving system in the city was studied. The common tools (queuing theory, system dynamics (SD) and discrete event dynamics simulation (DES)) were compared and it is found that DES is more suitable, in particular Petri nets (PNs), deemed to be the best choice for the purpose of this thesis. The model in this research was constructed on the basis of Hierarchical Coloured Petri nets (HCPNs), a combination of two extended PNs: Coloured PNs (CPNs) and Hierarchical PNs (HPNs). The model is able to simulate and predict patients' waiting times. Given that the structure of the model developed by HCPNs is still too complex, two extensions to CPNs, Ordered CPNs (OCPNs) and Prioritized HCPNs (PHCPNs), were proposed in this study to reduce the complexity of the model. Validation of the model was performed using the data of Saskatoon Health Region - Royal University Hospital. The results have shown that the proposed model can effectively describe the real system. The model has potential applications in decision-making for the selection of an optimal booking strategy to shorten waiting time and in the prediction of possible waiting time of the system in the future, which may assist MRI administrators in the management of medical resources and may greatly improve the quality of MRI service.

O sistema de proteção técnica contra incêndio (SPTCI) é um dos principais sistemas que compõem o edifício inteligente (EI), pois a eficiência do seu funcionamento afeta diretamente a segurança das pessoas e o patrimônio do prédio. O SPTCI é composto de diferentes dispositivos, estratégias de controle e atua segundo legislação específica. Devido à complexidade do SPTCI, torna-se fundamental uma modelagem adequada que permita verificar a dinâmica do sistema e sua relação com outros sistemas prediais. Neste contexto, este trabalho propõe um procedimento para a modelagem e análise de estratégias de controle para o SPTCI, integrado com outros sistemas prediais dentro do contexto de EI. A abordagem considerada para este propósito baseia-se na teoria dos sistemas a eventos discretos, na aplicação de técnicas derivadas da rede de Petri e em técnicas de análise através de simulação discreta. Com esta abordagem são desenvolvidos modelos do sistema de controle do SPTCI onde é considerada a sua relação com outros sistemas prediais. Particularmente, explora-se as extensões da rede de Petri como as técnicas Production Flow Schema e Mark Flow Graph. Um estudo de caso é apresentado para ilustrar as principais características deste procedimento. / From the point of view of property damage and personal security, the fire protection system (FPS) is one of the most important systems in an intelligent building (IB). The FPS is composed of several devices and control strategies. Furthermore, it must act in accordance with specific laws. As a consequence the design of FPSs is a complex task and it is very important to provide an adequate model that supports the verification of the FPS dynamics and its integration with others building systems, facilitating its test and validation. In this context, this work proposes a procedure to model in a systematic and rational way a FPS in the IB context. Considering the nature of the structure and processes of FPS the approach is based on the discrete event dynamic system theory and the application of the Petri net. Then, the models the FPS control system and the controlled plant must include its integration with other building systems. Particularly, it explores Petri net extensions such as Production Flow Schema and Mark Flow Graph techniques. Through an example it is illustrated the main aspects of the proposed procedure.

O sistema de proteção técnica contra incêndio (SPTCI) é um dos principais sistemas que compõem o edifício inteligente (EI), pois a eficiência do seu funcionamento afeta diretamente a segurança das pessoas e o patrimônio do prédio. O SPTCI é composto de diferentes dispositivos, estratégias de controle e atua segundo legislação específica. Devido à complexidade do SPTCI, torna-se fundamental uma modelagem adequada que permita verificar a dinâmica do sistema e sua relação com outros sistemas prediais. Neste contexto, este trabalho propõe um procedimento para a modelagem e análise de estratégias de controle para o SPTCI, integrado com outros sistemas prediais dentro do contexto de EI. A abordagem considerada para este propósito baseia-se na teoria dos sistemas a eventos discretos, na aplicação de técnicas derivadas da rede de Petri e em técnicas de análise através de simulação discreta. Com esta abordagem são desenvolvidos modelos do sistema de controle do SPTCI onde é considerada a sua relação com outros sistemas prediais. Particularmente, explora-se as extensões da rede de Petri como as técnicas Production Flow Schema e Mark Flow Graph. Um estudo de caso é apresentado para ilustrar as principais características deste procedimento. / From the point of view of property damage and personal security, the fire protection system (FPS) is one of the most important systems in an intelligent building (IB). The FPS is composed of several devices and control strategies. Furthermore, it must act in accordance with specific laws. As a consequence the design of FPSs is a complex task and it is very important to provide an adequate model that supports the verification of the FPS dynamics and its integration with others building systems, facilitating its test and validation. In this context, this work proposes a procedure to model in a systematic and rational way a FPS in the IB context. Considering the nature of the structure and processes of FPS the approach is based on the discrete event dynamic system theory and the application of the Petri net. Then, the models the FPS control system and the controlled plant must include its integration with other building systems. Particularly, it explores Petri net extensions such as Production Flow Schema and Mark Flow Graph techniques. Through an example it is illustrated the main aspects of the proposed procedure.