Troeps knowledge servers
Experimental server of the
Exmo team
Executive summary:
Co4 is an
environnement enabling a group of geographically distributed users to build
together a knowledge base accessible through the worldwide web. This is applied
to scientific knowledge base construction (in genomics) and corporate memories
(in micro-electronics). To that extent, the object-based knowledge representation
system Troeps can be turned into a knowledge server allowing to browse, query and edit
structured knowledge. This knowledge is also linked to informal text, pictures,
a lexicon and other web sites. The collaboration between users is managed by a
protocol which warrants that common knowledge bases are consistent and consensual.
The protocol is implemented as library that can be used for other applications
which aim is the collaborative construction of an artefact.
Direct access to information:
K. servers version 1.3:
Knife |
S. T. and G. |
Coligene
(local) |
Real
estate |
Launch the server
Workplan and achievements:
Our research objective (until year 2000) was the complete
design and experimentation of an environnement enabling a group of
geographically distributed users to build together a knowledge base
accessible through the worldwide web. During the 1995-1997 period,
our knowledge base management system Troeps has been made available
to the Web (knowledge server part) and the theoretical
foundations for concurent modification of the knowledge has been laid
out (Co4 protocol and work on knowledge base
revision). Then (1998-1999), the Co4
protocol has been implemented, verified and connected to the
Troeps knowledge servers. The system has been experimented for
internal use and delivered to a couple of sites.
Troeps knowledge servers allow to use
Troeps
as a HTTP server instead of a knowledge base system. Then, anyone can
browse and edit the knowledge base with the help of a HTTP client (such as Mosaic
or Navigator or Explorer). [o] is a review of related projects worldwide.
In various scientific domains, such as molecular biology, the important
flow of experimental data leads to the design and the management of
large knowledge bases. Four categories of knowledge can be identified:
descriptive knowledge on the entities of the domains; behavioural
knowledge on the dynamic behaviour of these entities; methodological
knowledge on the methods which can be used to identify these entities
and to complete their descriptions; terminological knowledge on the
relationships between the names used in the knowledge base and the terms
used in the domain.
Knowledge bases can be used as Web servers whose skeleton is the
structure of formal knowledge (mainly in the object-based formalism)
and whose flesh consists of pieces of texts and images tied to the
objects (see
[Euzenat1996a]).
The advantages of such an approach are found in the consistency
of the base (there are no dangling link since the skeleton is generated
automatically) and the opportunity to build complex queries
grounded on the formal knowledge (see figure). For instance, a user
looking for an apartment in a real estate knowledge base can first
select a filter form from the "house" concept, ask for the meaning of
the slot/word "F3" to the lexicon and decide to fill the form with
corresponding criteria; the user can select one of the objects given as
answers and have a look at the ground map and a picture of the house
together with the usual precise information. This combines the
advantages of a very structured server with the freedom of usual
servers. This participates in the Knowledge medium idea promoted by
Mark Stefik and can be called an "intelligence added" web server.
A server on E. coli genome has been built with our previous
work and we are involved in the craft of a knowledge base on the fly
(D. melanogaster) genome.
The Troeps knowledge bases are both browsable and editable through
the World-wide web (though the knowledge bases below are in read-only
mode). The graphic user interface is still the same but allows the
user to create, modify or destroy the objects and the conceptual
scheme of the knowledge base.
Editing raises problems of consistency and concurent access to the base.
This is the subject of the Co4 line of our work.
You can consult the following knowledge bases:
- The real
estate knowledge base (used for demonstration purposes);
- The ColiGene
knowledge base about E. coli genetic expression (demonstrates the HTML link; this is a partial translation of an old base);
- The Knife knowledge base about D. melanogaster genetic interactions (unpolished version; for computer scientists only);
- The STG bibliographic base about space, time and granularity (under construction);
Technical details can be found here.
The cooperative construction of knowledge bases aims at expressing
the consensus between a community of geographically distributed people.
We also plan to use Co4 and its architecture in corporate memory
applications.
The purpose of Co4 is the building of knowledge bases which are:
- Consensual
- since everything in the base has been accepted
by the people involved in the construction;
- Cooperatively constructed
- since people cooperates in order
to build the knowledge base;
- Consistent
- since they are stored under a formal repository
of knowledge (and checked for consistency);
- The last Co
- stands for connaissance (knowledge).
Co4 depends upon a simple architecture of related knowledge bases and
a formal protocol for submitting and discussing knowledge which is
freely inspired from those used in scientific journals.
The principles of Co4 are as follows: Each researcher has a knowledge
base (browsable through a knowledge server) from which knowledge can be isolated
and submitted to the consensual knowledge base (called group base).
The latter base will then contact the other members of the group for
acceptation, rejection or comments on the submitted piece of knowledge.
This raises problems of formal comparison and merging of contributions
from several knowledge sources and of designing a robust protocol for
such a task.
A relevant paper is [Euzenat1995a].
A complete protocol has been designed for these
activities. Its description can be found in [Euzenat1997a]. A
demonstration is also
available on video.
It has been expressed into LOTOS and checked for various
kinds of deadlocks.
It has been implemented into a
UNIX library [Sherpa1998] and is now freely available. For the communication, the KQML
application programming interface from EIT (Lockheed) is used. It
has been extended towards asynchronous message transmission.
http://co4.inrialpes.fr
Updated by Jerome
. Euzenat À inrialpes . fr on 20/4/2003