Presenter/Author Information

D. Pullar

Keywords

simulation, modelling framework, gis

Start Date

1-7-2002 12:00 AM

Abstract

The paper presents a modelling framework to integrate dynamic analysis and spatial analysis, andto apply this to a hydrological application. The dynamic analysis runs a simulation of a set of processmodules. Modules for spatial analysis functionality are implemented in software libraries, or components.Currently we support components for a map algebra language called MapScript, and for spreadsheetcalculations using Excel. An important issue in environmental models and in any modelling framework isdealing with different scale processes. When processes occur over different time or spatial scales but are stillintegrally related, this becomes a problem for applying efficient modelling solutions. The paper reviews twocommon strategies for solving this problem, namely multistep and multigrid methods. Because of theheterogeneous nature of landscapes processes neither is seen as offering a satisfactory solution. We have trieda variant to a multistep solution by allowing the user to specify the timing of different processes that occur ina landscape model. The paper describes the modelling framework and language specification used todescribe module execution. The specification is written in XML to leverage its widespread use in webcomputing environments. The modelling framework may be used for diverse modelling applications inhydrology, landscape assessment, geomorphology and ecology. The paper will demonstrate a mockhydrological application to model runoff in a small watershed.

COinS
 
Jul 1st, 12:00 AM

A Modelling Framework Incorporating a Map Algebra Programming Language

The paper presents a modelling framework to integrate dynamic analysis and spatial analysis, andto apply this to a hydrological application. The dynamic analysis runs a simulation of a set of processmodules. Modules for spatial analysis functionality are implemented in software libraries, or components.Currently we support components for a map algebra language called MapScript, and for spreadsheetcalculations using Excel. An important issue in environmental models and in any modelling framework isdealing with different scale processes. When processes occur over different time or spatial scales but are stillintegrally related, this becomes a problem for applying efficient modelling solutions. The paper reviews twocommon strategies for solving this problem, namely multistep and multigrid methods. Because of theheterogeneous nature of landscapes processes neither is seen as offering a satisfactory solution. We have trieda variant to a multistep solution by allowing the user to specify the timing of different processes that occur ina landscape model. The paper describes the modelling framework and language specification used todescribe module execution. The specification is written in XML to leverage its widespread use in webcomputing environments. The modelling framework may be used for diverse modelling applications inhydrology, landscape assessment, geomorphology and ecology. The paper will demonstrate a mockhydrological application to model runoff in a small watershed.