![](bg4.png)
dicators and graphs which are easily understandable
by professionals. Some applications are already on-
line and used by scientists, students and agricultural
advisors.
User browser
Service Web
PyVLE
VLE
Framework Pylon
Python
User database
Server
Figure 2: The main elements of the RECORD web archi-
tecture.
4 CONCLUSIONS AND
DISCUSSION
Since 2007, choices have been made for the develop-
ment of the platform RECORD. First, it has been de-
cided that all features that were required should not be
part of one unique tool, in light of the large range of
disciplines that are involved. Nevertheless the techni-
cal solutions should not restrain the different commu-
nities to a confined set of methods and tools. Techni-
cal solutions for model development, model analysis
and web applications are the following:
• The software VLE provides an IDE for designing
and coupling models. Coupling properties are en-
sured by the DEVS theory which is the basis of
VLE. This IDE can be used to perform the first
simulations.
• R and its libraries are used for analysing and ex-
ploring models. The platform relies on a specific
R package that links R to VLE.
• Python and its libraries are the basis of web ap-
plications development for RECORD projects,
thanks to a link between Python and VLE.
A large set of methods and tools are thus possibly
carried out into the platform. Due to this integration
strategy, there are few assumptions that are made re-
garding the methods that are involved. For example,
parameter estimation of a model using R can be per-
formed in different ways. The challenge of RECORD
is to identify well suited methods with the help of ex-
perts and to build training courses which are provided
through an E-learning web site and 3-days practice
sessions (2 per year).
We finally argue that integrating tools is the best
solution to develop a collaborative platform. An-
other important task that the platform team addresses
is to facilitate the collaborative work. The solutions
proposed and which are currently under construction
comprise the package management system into VLE,
attachment of meta-data to packages and models for
documentation and configuration.
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