Multi-experts scheduling system for real-time applications

This thesis focuses on the decisional process of autonomous systems, and more particularly, on the way to take a decision when the time at disposal in order to assess the whole situation is shorter than necessary. Indeed, numerous systems propose solutions to the user that are more and more "intelligent", or at least more personalized and adapted to the present context. As the process of taking a decision is complex, it exists different methods of resolution based on hypothesis and/or methods being complementary and/or concurrent. The three following examples exhibit different domains where the use of several methods of resolution would be of prime interest : Financial market investments : numerous studies on the volatility of the financial markets have been performed in order to build an automatic system being able to select the content of the optimal portfolio. Its diversity should promote the financial gain while minimizing the risks of the investments. However, it is difficult to guarantee that a single method is sufficiently robust against the chaotic variations of the financial markets. Video compression became more democratic since the large usage of the World Wide Web, handheld game player and mobile phones. The compression methods mainly cut the image in different regions, named macroblocks. Various methods of compression are applied onto these regions depending on some of their characteristics : static macroblock (i.e. steady background), or macroblock containing a moving object or moving scene. The goal is to guarantee the highest compression ratio for all the macroblocks, while maintaining the visual quality without any artifacts onto the architecture used to play the video. Speech recognition is used in an increasing number of services, for example mobile phones can compose automatically the phone number of a person present in the contact names, only by pronouncing his name. It exists also different softwares which allow to transcribe under typed shapes, the stream of word dictated in a microphone. The variability of the human voices, the local accents, the regional pronunciations, and the presence of background noise into the various speech samples can affect more or less significantly one or another of the recognition methods. An "agent" is an instance which uses a methodology leading to a particular solution of a given problem. Thus, if the same problem can be solved with 5 different methods, then it exists at least 5 different agents. The use of a multi-agent system handling various resolution methods (agents), increases the knowledge of a given problem, and thus increases also the robustness of the proposed solution with regards to a single agent solution. Comparing the results of the different agents allows using the competition between them, but also their ability to cooperate in order to build a robust solution. However, the time at disposal limits the number of used agents. In the previous example, it would be possible to us