For an early account of what the architecture of multi-user environments
in VRML look like,
As indicated before, there is a large variety of potential
applications for RM3D-DLP technology, including
information retrieval and delivery,
presentation and navigation agents,
Assuming that such applications require intensive knowledge
they may clearly benefit from our approach.
Our work is related to or even shows resemblance with
a number of other projects.
We will discuss:
- [Logic] -- logic programming for the internet
- [Scripts] -- merging VRML with logic scripts
- [Jinni] -- client-side logic with VRML
- [DIVE] -- distributed interactive virtual environment
- [Parlevink] -- agents in VRML worlds
- [Alice] -- 3D interactive programming environment
An overview of logic programming languages for the
Internet is given in Andrew Davison's [Logic].
Due to its late arrival on the Web scene, DLP is not mentioned
in this overview. It was, however, mentioned in a previous
overview of the same author [Survey], in the category
of object-oriented extensions.
For your information, the principal investigator organized
a workshop at WWW6 in 1997 entitled
Logic Programming for the Web, [Workshop].
There have been a number of attempts to improve on
the scripting capabilities of VRML.
One example of interest, from our perspective,
is the extension proposed in [Script],
which allows for logic programming in VRML script nodes.
This approach affects the VRML files themselves, and hence
the VRML97 standard.
As a drawback, existing VRML content cannot be (re)used
More importntly, however, such an approach does not allow
for migrating to newer or other scenegraph-based formats
such as X3D or Java3D.
In effect, Jinni (developed by Paul Tarau)
was a source of inspiration for our
first DLP+VRML prototype, [Jinni].
Nevertheless, our DLP language is semantically more suited
to deal with the complexities of a more tight coupling
of VRML and logic programming.
In particular, multi-threaded objects in DLP allow
for receiving events in an asynchronous manner,
which is impossible to do in ordinary sequential Prolog.
Distributed applications in Jinni are possible using
a Linda-style shared tuple space.
In our approach we rely on rendez-vous communication
and server-side mediator objects.
As the soccer prototype shows,
it is rather easy to create a shared repository of
state information using agent communication primitives
The DIVE project at the Swedish Institute of Computer Science
is an example of a complex heterogeneous system for
developing multi-user virtual communities, [DIVE].
It is offers support for a variety of graphic
formats, including VRML,
and allows for scripting behaviors and interactions
DIVE applications and activities include virtual battlefields, spatial models of interaction, virtual agents, real-world robot control
and multi-modal interaction.
DIVE is supported on a variety of platforms.
The first DIVE version appeared in 1991.
Our approach clearly builds on later developments, in particular
Java, to achieve cross-platform portability.
In contrast to the heterogeneous nature of the DIVE platform,
we provide a unified language framework as a programmatic
interface for the creation of 3D content and behavioral properties.
The Dutch Parlevink project, at the University of Twente,
has developed a virtual theater, which demonstrates
that agents may usefully be employed in (VRML-based)
virtual environments, [Parlevink]
The focus of the Parlevink project, however, is more
on cognitive models and natural language processing.
In contrast, our goal is to improve virtual environment
technology itself, by
providing a unified framework for developing agents
and virtual environments.
Finally, we cannot conclude this brief overview of
related work without mentioning Alice,
a 3D interactive programming environment for virtual worlds,
developed at Carnegie-Mellon University, [Alice].
One interesting feature of Alice is that it allows for programming
generic behavioral properties in the object-oriented scripting
Nevertheless, we believe that due to the knowledge-intensive
nature of the programming tasks required for
developing real applications in rich media virtual
environments, a logic-based language such as DLP
will in the long end be much more effective.
embedding in education: focus on multimedia
focus on multimedia
The research will have a clear impact on the educational activities
for the specialisation multimedia, in particular the Multimedia
Authoring II course, as indicated below.
It is to be expected that student projects will deploy the technology
developed within the AVID project.
In the first year students
start with a general Introduction to Multimedia.
This course centers around three themes:
the convergence between media, platforms and delivery technology,
the availability of
broadband communication and its impact on the development of
standards such as MPEG-4, and multimedia information retrieval
as an essential ingredient of the growing multimedia information repository
on the Web.
There are two follow-up courses, which are given in respectively the
second and third year:
The first of these courses deals with the technology for creating 3D scenes and
worlds, whereas the second is
more focused on providing intelligent services in virtual environments.
Students use the DLP+VRML framework for their assignment in the second course. See [Intelligent].
embedding in research: (intelligent) multimedia
SIKS report (2001)
Over the past six years, our research efforts
have focussed on developing models and software
architectures for multimedia and hypermedia
(A full version of this description, including publications, is available online in the SIKS report (2001)).
This research has resulted in two Ph.D. theses:
- 10/4/2001 -- Structured hypermedia -- a matter of style
- 8/5/2001 -- Diva: Architectural Perspectives on Information Visualization
For both theses, prof. dr.J.C. van Vliet was promotor,
and the principal investigator had daily supervision and acted as co-promotor.
The hypermedia work was done in collaboration with
dr. L .Hardman and dr L. Rutledge from the CWI Multimedia
This cooperation resulted in the formalization of the
Amsterdam Hypermedia Model, an extension of the Dexter
Hypertext Reference Model.
The hypermedia project also resulted in a software
framework for developing web-based hypermedia applications,
the hush library and its music and video extensions.
The visualisation project concerned the use of
animations and visualisation to display business process
simulation results in a hypermedia context.
During the project the focus shifted towards visualisation,
in particular business visualisation.
Also, explorations were done to investigate interactive
visualisation in 3D.
Our current research efforts are directed towards
developing a high-level platform for rich media 3D virtual
Our goal is to study aspects of the deployment and
architecture of virtual environments as an interface to multimedia information systems.
The intelligent multimedia research theme may
be regarded as continuing the hypermedia and visualisation
projects described before.
Our efforts are directed towards realizing the technology
needed for developing intelligent multimedia applications.
In particular, we aim for developing demonstrators in the area
of persuasive technology, and thus explore design methods
and patterns for the realization of emotionally charged virtual worlds.
This work is being done in cooperation with dr. C. Dormann
and dr. Z. Ruttkay from CWI.
The list below summarizes the cooperations that are due to
either the position of the research group within the department
or contacts resulting from previous research, as sketched above.
- multi-agent research group at VU/AI (dr. C. Jonker)
- HCI at VU/IMSE (dr. G. van der Veer)
- persuasive technology VU/IMSE (dr. C. Dormann)
- Facial and Avatar Animation Group at CWI & Epictoid (dr. Z.Ruttkay)
- Multimedia Authoring Group at CWI (dr. J. van Ossenbruggen & dr. L. Rutledge)
7) Work Programme
With reference the our discussion of the steps that must be
taken to realize our research goals and the
topics that need to be addressed we suffice by giving
a brief summary of the deliverables that we expect to produce
during the four years of the project.
- year 1: realization of Web Agent Framework (WAF)
- year 2: realization of ACL for multi-user environments (MU-ACL)
- year 3: integration of WAF and MU-ACL
- year 4: thesis
The online version has links to online copies of most
of the cited references.
- Wolfgang Broll, Leonie Shäfer, Tobias Höllerer, Doug Bowman,
Interface with Angels: the future of VR and AR interfaces, IEEE Computer Graphics, November/December 2001, pp. 14-17
- Web3D Consortium,
Java3D API, java.sun.com/products/java-media/3D
- Zhisheng Huang, Anton Eliëns, Alex van Ballegooij, Paul De Bra,
A Taxonomy of Web Agents, IEEE Proceedings of the First International Workshop on Web Agent Systems and Applications (WASA '2000), 2000.
- A. van Ballegooij and A. Eliëns,
Navigation by Query in Virtual Worlds, Web3D 2001 Conference, Paderborn, Germany, 19-22 Feb 2001
- Zhisheng Huang, Anton Eliëns, and Paul De Bra,
An Architecture for Web Agents, Proceedings of the Conference EUROMEDIA 2001, 2001.
Zhisheng Huang, Anton Eliëns, and Cees Visser,
Programmability of Intelligent Agent Avatars, Proceedings of the Agent'01 Workshop on Embodied Agents, June 2001, Montreal, Canada
- Zhisheng Huang, Anton Eliëns, and Cees Visser,
3D Agent-based Virtual Communities, submitted to Web3D 2002
- A. Eliëns,
DLP -- A language for Distributed Logic Programming, Wiley, 1992
- A. Eliëns ,
Principles of Object-Oriented Software Development (2nd edn), Addison-Wesley (2000)
- Cees Visser, Anton Eliëns,
A High-Level Symbolic Language for Distributed Web Programming, Internet Computing 2000, June 26-29, Las Vegas
- C. Dormann & A. Eliëns,
Exploring the design space for emotive dialogues, submitted to: Third Int Conf on Emotion and Design
- Lloyd Rutledge, Alex van Ballegooij and Anton Eliëns,
Virtual Context - relating paintings to their subject, Culture Track of WWW9 in Amsterdam, The Netherlands, Tuesday, May 16th, 2000
- Yannis Labrou, Tim Finin and Yung Peng,
The current landscape of Agent Communication Languages, IEEE Intelligent Systems, Vol. 14, no. 2, 1999
- Wolfgang Broll,
VRML and the Web: A basis for Multi-user Virtual Environments on the Internet, In Proceedings of WebNet96, World Conference of the Web Society (San Francisco, CA, Oct. 16-19, 1996), H. Maurer (ed.), AACE, Charlottesville, VA (1996), 51-56.
- A. Davison,
Logic Programming Languages for the Internet, Chapter in Computational Logic: From Logic Programming into the Future, Antonis Kakas, Fariba Sadri (eds.), Springer Verlag (2001). available from: fivedots.coe.psu.ac.th/~ad
- A. Davison,
Enhancing VRML97 Scripting, Euromedia'2001, Valencia, Spain, April 18-20. available from: fivedots.coe.psu.ac.th/~ad
- P. Tarau,
Jinni: Intelligent Mobile Agent Programming at the Intersection of Java and Prolog, Proc. of PAAM'99, London, UK, April, see also www.binnetcorp.com/Jinni
- Distributed Interactive Virtual Environment,
Interactive Colloborative Environments, SICS, www.sics.se/dive
- University of Twente,
Language Engineering Group,
- Carnegie-Mellon University,
3D Programming Environment, www.alice.org
- Zhisheng Huang, Anton Eliëns, Cees Visser,
Intelligent Multimedia Technology: An Approach to Combine Agent Technologies with Multimedia, in preparation
- A. Davison,
A survey of Logic Programming-based Object-Oriented Languages, In Research Directions on Concurrent Object-Oriented programming, G. Agha, P. Wegner, A. Yonezawa (eds.), MIT Press (1993)
- A. Eliëns (chair),
Logic Programming and the Web,
10) Requested Budget
- the amount of euro 129.879 includes the benchfee for travel expenses and other support.
- the VU will provide an additional 2 years of programmer support.
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