XML Schema for the Simulation Data Model

[Rick Wagner]

Hi Gerard,

> If you study turbulence in some gas cloud you could have a target  
> object type instance "cloud" and a process instance for "turbulence".

I'm still going through your entire response, but I realized that  
this statement made it possible for me to make a concrete design  
suggestion for the model:

>

The model must be able to describe simulations for which there is no  
target object.

Some physics models have application on a range of scales, like  
turbulence and Plummer spheres. For turbulence, the target object is  
really "compressible fluid", which doesn't carrying the same meaning  
as "cloud". Especially since the simulation results could be applied  
to molecular clouds or the Jovian atmosphere.

I think the target object is useful for most simulations, since we  
often are numerically modeling a particular type of object (cloud),  
or even a particular object (Perseus). But, not all simulations,  
especially the ones that are more of numerical experiment than a  
numerical model.

--Rick