Dualism in geographic information visualization
地理信息可视化中的二元方法论

As a significant approach to geographic information visualization,map making is practiced by not only professional cartographers but also more and more general public.However,the latter is often rarely equipped with knowledge of cartography.Instead of comprehensive theories and methods of cartography,simplified mapping skill might be suitable for them to make maps with respect to their special purpose.As a preliminary study,this paper aims to explore and build a conceptual model of duality for geographic information visualization.Dualistic analysis is employed to establish an easy-to-be-understood framework which could be followed as a "map-making guide".First,the paper introduces the theories of dualism in terms of other disciplines,such as geography,linguistics and philosophy.Then,with semiotic linguistics as a normal form,the methodology of dualism for geographic information visualization is elaborated from the perspectives of the signifier and signified of geographic information visualization.Our analyses demonstrate that:(1)geographic information is of duality,such as the duality of time and space,the duality of instant and interval,the duality of geometry and attributes,the duality of qualitative and quantitative approaches,etc.;and(2)map design is also full of various dualities such as the duality of the entire format of a map and individual symbols,the duality of outline and fill of a symbol,the duality of shape and size,the duality of color and texture,and so on.