Describing data formats of geographical models

Abstract

The variations that characterise the design and implementation of geographical models create significant difficulties in the sharing of models. One such difficulty concerns the fact that geographical models and data are highly coupled, and various heterogeneous data formats exist. This results in a laborious and unending data format conversion process during model sharing. In this paper, data format is defined to include three components: data type, structure and layout. A new method is proposed to clearly describe data formats of geographical models in a universal manner in an attempt to solve the problem identified above. First, the characteristics of geographical models, data and their formats were analysed. A concept model of data formats was then proposed, focusing on data location, data types and separators. A novel data format description language called the Data Format Markup Language (DFML) was designed accordingly. DFML uses XML markup elements to describe format information. The primary markup elements and syntax rules of DFML are introduced, and the use of DFML to describe data formats is explained step by step. Finally, case studies were performed to test this approach with two types of data formats: (1) data formats of a watershed model: Soil and Water Assessment Tool (SWAT), and (2) typical GIS data formats, namely, the ESRI ASCII Raster and shapefile formats. The results of these case studies demonstrated that DFML is easy to understand and use and can adequately describe data formats of geographical models.

Developing dynamic virtual geographic environments (VGEs) for geographic research

“…This model undertakes data exchange tasks well while integrating different geo-process models as well as expressing multi-source heterogeneous data in a clear, visual and formalized way. Similar work was conducted by Hu et al (2015), providing a Data Format Markup Language (DFML) to describe the data formats of geo-process models using three components: data type, structure and layout.…”