In order to support location-aware apphcations it is necessary to locate people and equipment in near rerd-time.To avoid unnecessary exposure of details of the underlying tracking and positioning systems.researchers have proposed an additiond layer of indirection between sensors and app~lcations: a location service.In this paper, we examine how such a service should acquire and integrate location data from multiple heterogeneous location subsystem.We propose a fusion algorithm based on a formrdly defined, hierarchicrd location model.The algorithm can identify and exploit overlaps among location sightings to improve accuracy.Moreover, inconsistencies can be detected and dedt with either by finding the least common denominator, or the most ~iely rdternative.1.1

The ViewPoints framework for distributed and concurrent software engineering provides an alternative approach to traditional centralised software development environments.WJe investigate the use of decentralised process models to drive consistency checking and conflict resolution in this framework.Our process models use pattern matching on local development histories to determine the particular situation (state) of the development process, and employ rules to trigger situationdependent assistance to the user.We describe how communication between such process models facilitates the decentralised management of explicitly defined consistency constraints in the ViewPoints framework.