Environmental Modelling at Nottingham

Home

Radionuclides

Heavy Metals

Ecosystem Processes

Modelling Methods & Software

OpenModel

Some of our modelling work is heavy duty stuff requiring computer codes and numerical method libraries and so on. On the other side some of it is the modelling component of an otherwise experimental or field project. Often this latter type of work is undertaken by people who don't have much programming experience. It is with this group of people in mind that we have always been interested in the use of modelling packages such as Stella, VisSim etc. We even started the development of one! (ModelMaker)

These kinds of package are really great if what you want to do can be accomodated. However it is common to run up against a constraint of the package - usually after a lot of effort has gone into developing a model! It is very frustrating if all you want is an additional output of some kind, and you know the numbers are inside the package, but it is a closed, shrink wrapped system, and you can't get them out. Re-doing the model in another system, can cause tears (really!).

Over time this situation has led to the development of our home-made modelling package, OpenModel. Open because when we need to add something to it, we can.

Initially OpenModel was similar to ModelMaker in scope but with a wider range of parameter estimation methods. However we now reached the point where we are using it for some of our most sophisticated work.

Key Features

  • Modular stucture using equationsets and flowcharts
  • Standard text specification of equations (aradigm is the solution of ordinary differential equations)
  • Support for raster spatial models
  • Tabular, graphical and spatial outputs
  • Model Parameterisation (variety of methods: Marquardt, Powell, Simulated Annealing, MCMC (Metropolis-Hastings)
  • Classical and Bayesian Uncertainty estimation
  • Model Averaging
  • Model Simplification
  • Code generation (so models can be ported to other platforms; e.g. for parallel processing)

OpenModel is not commercially available and we have no intention of developing it in that direction.

Click here to download an executable version (zip file). Installation simply requires to to extract to a folder and set a shortcut to OpenModel.exe

We hope to make an opensource version available in due course.

For more information contact: neil.crout@nottingham.ac.uk