Contenu du sommaire

The analysis of social networks is an area of significant research concerned with forms of communication insofar as these forms play a role in the creation or maintenance of social relationships. The emergence of electronic communication within the context of these networks raises a specific set of questions concerning the evolution of the network structure which is brought about by the growing access to this type of communication. This article considers the regular correspondents of some researchers in Toulouse and describes the types of evolution involved. As may be expected, the role of proximity in the creation and maintenance of social relationships shows signs of weakening. Social networks based on a heavy use of electronic communication show interesting structural specificities which differentiate them from "ordinary" networks, and demonstrate traits similar to those which characterize the social networks in large cities with respect to the networks in less urbanized areas. This result suggests the hypothesis of the "hyper- ville" which tends to turn widespread electronic communications into an equivalent of urban processes, at least with respect to social relations.

Despite significant mutations in use, territorial shape and technology, the present form of the eastern Paris suburban bus routes was already present, in its basic principle, in the routes laid down with the first public surface transportation lines established in the 19th century. This morphological permanence of the system over time can be explained by the tremendous importance of the initial phase of development, as well as by the failure of transformation policies undertaken on several subsequent occasions. This permanence today raises an important question: will the bus system in the Paris suburbs be capable of adapting to metropolitan evolutions, or will it disappear with the increase in alternative modes of transportation, with which it currently operates?

The regionalization (decentralization) of short-distance railroad transportation has been an ongoing process in France for 20 years now. The