La production de la circulation ferroviaire nécessite l’utilisation et le partage deressources critiques et hétérogènes, notamment le réseau ferroviaire et lesressources roulantes et humaines. Un schéma communément adopté décompose laplanification selon les niveaux décisionnels et les ressources.Depuis les dernières années, les acteurs ferroviaires accordent un intérêt croissant àla robustesse de la circulation ferroviaire. Néanmoins, toutes les stratégies étudiéesse concentrent sur une seule ressource à la fois, négligeant ainsi le partage desressources et son impact sur la robustesse. Or, la séquentialité de la planificationdes ressources peut augmenter la propagation des retards sur les autres trains.L’intégration des décisions tactiques des trois ressources infrastructure, engins etagents de conduite peut aboutir à un plan de transport plus robuste dans le sens dela propagation des retards. Les motivations principales de la thèse émanent de cetteidée.L’objectif de ce travail est d’aboutir à des outils d’aide à la décision pour proposerune planification intégrée et robuste des ressources ferroviaires au niveau tactique.Nous proposons dans cette thèse plusieurs contributions :1. Un modèle d’optimisation qui vise à élaborer un plan de transport robuste destrois ressources critiques simultanément.2. Un modèle de simulation à événements discrets pour évaluer la robustesse desplans de transport. Nous tentons dans cette phase de reproduire le comportementréel du système ferroviaire et l’utilisation des trois ressources critiques. / The railway operations' planning consists in finding the best use of the available infrastructure, rollingstock and crew units to cover a given timetable. A commonly adopted scheme breaks down planningas decision-making levels and resources.However, the occurrence of perturbations may deteriorate the quality of the solutions or even makethem infeasible. Therefore, railway operators aim to find robust schedules that minimize the impact ofperturbations. To this purpose, the decisions made for each resource (infrastructure, rolling stock andcrew) must include the demand cover as well as the robustness objectives.Nevertheless, all tested strategies focus on a single resource at a time, neglecting resource sharing andits impact on the robustness. But the sequential scheme of resource planning can increase thepropagation delays on other trains. Integrating of tactical decisions of the three resourcesinfrastructure, rolling stock and crew can result in a more robust schedule that minimizes thepropagation of delays. The main motivations of the thesis come from this idea.The objective of this work is to develop decision support tools that provide an integrated and robustplanning of railway resources at the tactical level. We propose in this thesis several contributions:1. An optimization model that aims to develop a robust transport plan of the three critical resourcessimultaneously.2. A simulation model (discrete event) to assess the robustness of transport plans. We are trying at thisstage to reproduce the actual behavior of the rail system and the use of three critical resources.

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This thesis presents a new unified algorithm for cluster assignment and acyclic region scheduling in a partitioned architecture, and preliminary results on its integration into an experimental retargetable code generation framework. The object of this work is twofold. Firstly, to validate for the first time, and evaluate the framework which is almost automatic, so as to gain insights into possibilities for improvement. This was done by using as a baseline for comparison, highly optimized code generated by the handcrafted compiler of Texas Instruments, the TI Code Composer Studio V2. The second objective is to compare the integrated scheduling algorithm with another well known algorithm which performs scheduling and cluster allocation in the same phase, the Unified Assign and Schedule (UAS) algorithm. The computational complexity of the two algorithms is comparable. The components of the framework experimented with here are (a) a tree transformer generator, which takes as input, a description of the instruction set of the target architecture in the form of a regular tree grammar augmented with actions and attributes, and outputs a data dependency directed acyclic graph, (b) the well known public domain IMPACT front end for C, (c)a microarchitecture description module which uses a modification of the HMDES architecture description language of the TRIMARAN project, to include cluster information, and (d) a combined cluster allocator and acyclic region scheduler and a register allocator designed and implemented by us. Experiments have been carried out on creating the proper interfaces for all the modules to work together, and the targeting of the tool to the Texas Instruments TMS320c62x architecture to establish the feasibility of this approach. We present the results of our implementation on a set of benchmarks and some sorting programs and compare them with those obtained from the state-of-the-art TI compiler. The performance without software pipelining shows that our executables take on the average 1.4 times the execution time as that of those generated by the TI compiler. The integrated scheduling algorithm proposed in this thesis performs at least as well as the UAS algorithm and sometimes better by as much as 9 % in terms of the parallelism obtained.

no / Multimedia applications in wireless networks are usually categorized into various classes according to their traffic patterns and differentiated Quality-of-Service (QoS) requirements. The traffic of heterogeneous multimedia applications often exhibits the Long-Range Dependent (LRD) and Short-Range Dependent (SRD) properties, respectively. The integrated scheduling scheme that combines Priority Queuing (PQ) and Generalized Processor Sharing (GPS) within a hierarchical structure, referred to as PQ-GPS, has been identified as an efficient mechanism for QoS differentiation in wireless networks and attracted significant research efforts. However, due to the high complexity and interdependent relationship among traffic flows, modelling of the integrated scheduling scheme poses great challenges. To address this challenging and important research problem, we develop an original analytical model for PQ-GPS systems under heterogeneous LRD and SRD traffic. A cost-effective flow decomposition approach is proposed to equivalently divide the integrated scheduling system into a group of Single-Server Single-Queue (SSSQ) systems. The expressions for calculating the queue length distribution and loss probability of individual traffic flows are further derived. After validating its accuracy, the developed model is adopted as an efficient performance tool to investigate the important issues of resource allocation and call admission control in the integrated scheduling system under QoS constraints.