Clustering means partitioning nodes into groups called clusters, providing the network with a hierarchical organization. Overall, clustering increases the scalability of network management. For instance, clustering-based routing reduces the amount of routing information propagated in the network; members of a cluster can share resources; and clustering can be used to reduce the amount of inform...

In this paper, we deal with two important issues in relation to modular recon gurable manipulators, namely, the determination of the modular assembly con guration optimally suited to perform a speci c task and the synthesis of fault tolerant systems. We present a numerical approach yielding an assembly con guration that satis es four kinematic task requirements: reachability, joint limits, obst...

The goal of the research described in this paper is to build robotic systems that can execute motion tasks in real time. We present two ideas towards this goal: a real-time path planner for static three-dimensional con guration spaces and a new framework for the integration of planning and control. The planner is based on a new class of cells, slippery cells, incorporated in an approximate cell...

In this paper we investigate the e®ects of microphone and speaker locations on the performance of active noise control in ducts. We study a so-called \symmetric" con ̄guration in which the collocated performance microphone/control speaker and the collocated measurement microphone/disturbance source pairs are located equidistance from the duct center. By applying an \alignment angle" analysis to ...

Network con guration information can be very e ectively used for network tra c optimization and improving network performance. FTP tra c, one of the largest consumers of network bandwidth, is taken as a case study of how e ectively network con guration information can be used. The idea is essentially to provide a workable and scalable mechanism by which a user or an application can evaluate the...

We discuss possible options for the acquisition of radial velocities in parallel with the astrometric data for the global astrometry mission GAIA, currently under study in the framework of the scienti c programme of the European Space Agency. The scienti c rationale of a parallel radial velocity programme, in the light of the recent evolution of the GAIA concept toward signi cantly fainter magn...

Connguration Programming, based on Architecture Description Languages, and Meta-Level Programming are considered promising approaches in the software engineering eld. This paper shows that there is an immediate correspondence between some key concepts of Conngura-tion and Meta-Level Programming approaches and that some of the main issues to be solved for their deployment in real systems are qui...

Voice conferencing has attracted interest as a useful and viable rst real-time application on the Internet. This report describes Nevot a network voice terminal meant to support multiple concurrent both two-party and multi-party conferences on top of a variety of transport protocols and using audio encodings o ering from vocoder to multi-channel CD quality. As it is to be used as an experimenta...

Plane Couette ow perturbed by a spanwise oriented ribbon, similar to a con guration investigated experimentally at CEA-Saclay, is investigated numerically using a spectral-element code. 2D steady states are computed for the perturbed con guration; these di er from the unperturbed ows mainly by a region of counter-circulation surrounding the ribbon. The 2D steady ow loses stability to 3D eigenmo...