A central aim of the COVEN project was to prototype large-scale applications of collaborative virtual environments (CVEs) that went beyond the existing state of the art. These applications were used in a series of real-scale networked trials that allowed us to gather many interesting human and technological results. To fulfill the technological and experimental goals of the project, we have modified an existing CVE platform: the DIVE (distributed interactive virtual environment) toolkit. In this paper, we present the different services and extensions that have been implemented within the platform during the four years of the project. Such a presentation will exemplify the different features that will have to be offered by nextgeneration CVE platforms. Implementation of the COVEN services has had implications at all levels of the platform: from a new networking layer through to mechanisms for high-level semantic modeling of applications.

Multimodal conversational spoken dialogues using physical and virtual agents provide a potential interface to motivate and support users in the domain of health and fitness. In this paper we present how such multimodal conversational Companions can be implemented to support their owners in various pervasive and mobile settings. We present concrete system architectures, virtual, physical and mobile multimodal interfaces, and interaction management techniques for such companions. In particular, we present how knowledge representation and separation of low-level interaction modelling from high-level reasoning at the domain level makes it possible to implement distributed, but still coherent, interaction with Companions. The distribution is enabled by using a dialogue plan to communicate information from domain level planner to dialogue management and from there to a separate mobile interface. The model enables each part of the system to handle the same information from its own perspective without containing overlapping * Corresponding author Email addresses: mturunen@cs.uta.fi (Markku Turunen), jh@cs.uta.fi (Jaakko Hakulinen), olovs@sics.se (Olov Ståhl), gamback@sics.se (Björn Gambäck), preben@sics.se (Preben Hansen), mcrg@tid.es (Mari C. Rodríguez Gancedo), e.rsai@tid.es (Raúl Santos de la Cámara), c.g.smith@tees.ac.uk 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 logic, and makes it possible to separate task-specific and conversational dialogue management from each other. In addition to technical descriptions, we present results from the first evaluations of the Companions interfaces.

In a distributed shared synthetic environment with provisions for high quality 3D visualization and interaction, it is possible to implement a powerful variant of a roomslspace metaphor based on the concept of presence or proximity between participants in 3D space. This kind of model can be used as an interface between the user and the computer, for overview and control of applications, tile systems, networks and ofher computer resources, as well as for communication and collaboration with other users in the networked environment. We model proximity with a geometric volume of the immediate surroundings, [he aura, of the participant's representation in the synthetic environment. This proximity, or aura, is used to establish presence at meetings, to establish communication charnels and to provide interaction.

In this paper we describe The Pond, a system used to search for and visualise data elements on an engaging tabletop display. The Pond uses methods of unencumbered interaction and audio feedback to allow users to investigate data elements, and supports shoulder-to-shoulder collaboration with the physical Pond artefact mediating the collaboration between those people gathered around it. The user interface is based on an ecosystem metaphor, presenting data elements in the form of shoals of aquatic creatures inside a virtual 3D pond. The Pond is an interactive system offering an appealing and novel way to search for and interchange information. We describe the motivation and design choices behind The Pond, the system as it stands today, details of its implementation, and observations from a study of The Pond in use.

This paper describes how home appliances might be enhanced to improve user awareness of energy usage. Households wish to lead comfortable and manageable lives. Balancing this reasonable desire with the environmental and political goal of reducing electricity usage is a challenge that we claim is best met through the design of interfaces that allows users better control of their usage and unobtrusively informs them of the actions of their peers. A set of design principles along these lines is formulated in this paper. We have built a fully functional prototype home appliance with a socially aware interface to signal the aggregate usage of the user's peer group according to these principles, and present the prototype in the paper.