1st International Congress on Environmental Modelling and Software - Lugano, Switzerland - June 2002
Keywords
dynamic modelling, simulation, spreadsheet
Start Date
1-7-2002 12:00 AM
Abstract
Simulation of ecological systems represents more sophisticated analysis, which extends possibilities of standard research methods. In contrast to majority of computer languages available for calculation of dynamic models, spreadsheet models (TabSim-Table Simulation) offer to spend more effort on investigating the features of a dynamic system, rather than writing a program code. The program structures are replaced by table objects, which represent basic dynamic relations (integrations and time delays) and static relations (described by built-in functions and user functions). In addition to calculation of dynamic and static relations, the wide range of built-in graphs and graphic objects can be used for presentation of simulation results. The TabSim has been developed expressly for modelling systems described by time dependent, non-linear differential equations and transfer functions. Typical applications include energy transformation, chemical process representation, ecological relations and biomedical systems. The numerical solution is carried out by a number of algorithms. The basic level represents Runge-Kutta and Adams-Moulton algorithms with a variable step and order. Each structure of a numerical model can be solved directly by calculation of static functions inside a spreadsheet or transferred to an internal programming code. Simulation of dynamic models, preferentially of ecological systems, is demonstrated on a few examples that illustrate the process of development and solution.
Ecological Modelling Using the Spreadsheet Model TabSim
Simulation of ecological systems represents more sophisticated analysis, which extends possibilities of standard research methods. In contrast to majority of computer languages available for calculation of dynamic models, spreadsheet models (TabSim-Table Simulation) offer to spend more effort on investigating the features of a dynamic system, rather than writing a program code. The program structures are replaced by table objects, which represent basic dynamic relations (integrations and time delays) and static relations (described by built-in functions and user functions). In addition to calculation of dynamic and static relations, the wide range of built-in graphs and graphic objects can be used for presentation of simulation results. The TabSim has been developed expressly for modelling systems described by time dependent, non-linear differential equations and transfer functions. Typical applications include energy transformation, chemical process representation, ecological relations and biomedical systems. The numerical solution is carried out by a number of algorithms. The basic level represents Runge-Kutta and Adams-Moulton algorithms with a variable step and order. Each structure of a numerical model can be solved directly by calculation of static functions inside a spreadsheet or transferred to an internal programming code. Simulation of dynamic models, preferentially of ecological systems, is demonstrated on a few examples that illustrate the process of development and solution.
