Table of contents
SPENVIS is a WWW-based instrument intended to facilitate the use of models of
the spatial environment in a consistent and structured way. The SPENVIS system
consists of an integrated set of models of the space environment, and a set of
help pages on both the models and the SPENVIS system itself.
The project concept
At the heart of SPENVIS is the project concept. A project is defined as
the collective input to and output from the SPENVIS system for a series of
related runs. The physical representation of a project is a subdirectory on the
hard drive of the hardware system running SPENVIS. In this subdirectory, all
the input parameters are stored, together with all output files generated by
the system, until the deletion of the subdirectory (by the user or by the
SPENVIS team). This means that all the inputs and the outputs of a run are
conserved, so that an analysis can be performed over more than one session, as
the results are not lost upon leaving the system. In addition, it is not
necessary to re-enter the input parameters already defined in a previous run.
Project operations such as creation, deletion, switching are performed on
the project page which can be reached via the
project link in the menu bar that appears at the
top of each SPENVIS page.
Models implemented in SPENVIS
Most of the models implemented in SPENVIS require as input a set of point on a
spacecraft trajectory or a user-defined set of geographic points. These sets of
points are produced by two tools: the
orbit generator and the
coordinate grid generator. In general,
one of these tools has to be used before the models themselves can be accessed.
SPENVIS Is able to detect whether a spacecraft trajectory or a coordinate grid
has been generated: if this is not the case, the system will issue an error
message and prompt the user to run the orbit or coordinate grid tool, after
which the model in question can be run.
Once a trajectory or a coordinate grid has been generated, it can be used by
different models. This means that, in the context of a given
project, it is not
necessary to generate coordinates for each model separately.
Warning! When running the orbit or grid generator, all outputs
previously obtained with models that use the respective coordinate tool, are
deleted. This is to ensure consistency between results, and to avoid errors in
the plotting routines that produce the graphical output. The input parameters
for the models are not deleted, so that they can be run again in the same way.
The models implemented in SPENVIS
have been organised in the following packages:
Outputs from the system
SPENVIS Produces two types of output:
The Output link in the
menu bar at the top of each page points to a
page with a list of all
output files produced for the active project.
- HTML report files and ASCII tables that serve as
input for other models or for the plotting routines. A
list of all output files
with their format description is available.
- Graphical output, which is produced with the Interactive Data Language
(IDL) package, in a variety of
Last update: Thu, 20 Aug 2009