ECOLOGICAL MODEL DEVELOPPMENT by Computer Grid

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ECOLOGICAL MODELDEVELOPPMENT by Computer Grid

• Petras Zemlys
• Coastal Reasearch and Planning Institute
• Klaipeda University
• 2007

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• Two steps of the ecological modeling procedure of
  hydro ecosystems are most computer time
  consuming
• Sensitivity analysis
• Parameter estimation
• The computing time is growing with dimensionality
  of the model (when hydrodynamics is coupled with
  biology)

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• Sensitivity analysis

• Parameter sensitivity analysis attempts to
  provide a measure of the parameters (model
  constants) sensitivity to the state variables of
  greatest interest in the model.
• Though there are many formulations of the
  sensitivity analysis, the most cumbersome task is
  calculation of high number of model scenarios
  with different values of parameters.

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Curonian lagoon ecological model

• Curonian lagoon eutrophication model under
  development.
• Based on finite element hydrodynamic model SHYFEM
  (http//www.ve.ismar.cnr.it/shyfem) developed in
  Marine Research institute in Venice (Italy).

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Curonian lagoon ecological model

• Finite element discretisation scheme to reduce
  computing time.
• Number of state variables in ecological module
  -14
• Number of parameters 150
• Calculation time with one set of parameter values
  5-8 h

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Results in Litgrid

• Script for source compilation and execution.
• Script for production of JDL and input files with
  different parameter values.
• Testing in Grid environment

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Problems

• Problems with parametric jobs.
• Problems using GNU Fortran compiler on IA64.
• Weak clusters
• Unstable middleware

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• Thank you for attention!