Downtowns contribute significantly to the economy of cities and as a result, decision makers are increasingly recognizing the fundamental value and importance of maintaining viable downtown cores. Following the post-war era of urban decay and suburban expansion, there have been widespread attempts nationwide to reverse trends and to revitalize downtowns. In the Winnipeg context, urban renewal was practiced throughout the 1960s and 1970s; tripartite agreements were utilized during the 1980s; and development corporations were introduced throughout the 1980s and 1990s as a way to encourage private sector investment with targeted public sector investments. This practicum investigates the relationship between planning and development in the downtown revitalization context. In particular, this research aims to discover the extent to which a downtown development agency may have facilitated the better integration of planning and development in a city’s downtown, where revitalization has been very much on the public agenda. Winnipeg’s CentreVenture Development Corporation was used as a case study to explore this relationship. It was established in 1999 and continues to operate today. This paper attempts to determine the extent of its involvement, and the manner by which this arms-length government agency has aided and influenced tangible development in Winnipeg’s downtown. Furthermore, the case study was used to understand the nature, scope and form of related downtown revitalization, and to distill any learning about the general topic that might be applicable in other comparable settings. The practicum concludes by providing potentially transferable best practices to cities with similar characteristics and with recommendations for both CentreVenture Development Corporation and its shareholder, the City of Winnipeg.

Cette thèse porte sur l'ordonnancement des trains dans les gares complexes en forte densité de circulation. L'objet se situe à la réalisation d'un outil pour aider les managers de la gare à générer un tableau des horaires sans-conflits dans un journée. Le management des circulations ferroviaires dans la gare demande l'ordonnancement soigneux pour adapter les ressources limités, en évitant les conflits entre les trains et satisfaisant l'objectif et les politiques économiques et de la sécurité en même temps. D'après les méthodes appliquées en recherche opérationnelle et les expériences professionnelles, une modèle mathématique applicable aux gares différentes est construit pour formaliser le problème de l'ordonnancement des trains contenant la topologie de la gare, activités des trains, contraintes de planification et objectives. Comme un problème à grande échelle, l'ordonnancement des trains dans un journée est décomposé en sous-problèmes traitables dans l'ordre du temps par sliding window algorithme accumulé. Chaque sous-problème est résolu par branch-and-bound de CPLEX. Afin d'accélérer le calcul des sous-problèmes, tri-level optimisation méthode est construit pour offrir une solution optimale locale dans un temps de calcul assez court. Cette solution est donnée à branch-and-bound comme une solution initiale.Ce système consiste à vérifier la faisabilité des horaires donnés à la gare. Les trains avec les conflits insolvables sont retournés à l'origine de ces trains avec les modifications des heures proposées. Déviations des trains commerciaux sont minimisées pour diminuer la propagation du délai dans le réseau ferroviaire. / This thesis focuses on the trains platforming problem within busy and complex railway stations and aims to develop a computerized dispatching support tool for railway station dispatchers to generate a full-day conflict-free timetable. The management of rail traffic in stations requires careful scheduling to fit to the existing infrastructure, while avoiding conflicts between large numbers of trains and satisfying safety or business policy and objectives. Based on operations research techniques and professional railway expertise, we design a generalized mathematical model to formalize the trains platforming problem including topology of railway station, trains' activities, dispatching constraints and objectives. As a large-scale problem, full-day platforming problem is decomposed into tractable sub-problems in time order by cumulative sliding window algorithm. Each sub-problem is solved by branch-and-bound algorithm implemented in CPLEX. To accelerate calculation process of sub-problems, tri-level optimization model is designed to provide a local optimal solution in a rather short time. This local optimum is provided to branch-and bound algorithm as an initial solution.This system is able to verify the feasibility of tentative timetable given to railway station. Trains with unsolvable conflicts will return to their original activity managers with suggestions for the modification of arrival and departure times. Time deviations of commercial trains' activities are minimized to reduce the delay propagation within the whole railway networks.