Adaptive Methods for Mobile Cartography

The use of digital geoinformation is no longer restricted the domain of stationary computers. Falling prices of mobile information devices have made mobile geoinformation usage affordable to a wider public. Improved positioning techniques (GPS and radio network based) have shown their benefits in new technologies like Location Based Services (LBS). These services provide the user with relevant information based on the current position. We proceed on the assumption that one size does not fit all. LBS offer the potential to adapt information presentation in order to achieve a more user-focused service. However, there are many more aspects of a mobile usage situation that a service can be adapted to. Moreover, the information itself is not the sole target of adaptation. This paper introduces the basic concept of adaptation and its transfer to cartography. The differences of adaptability and adaptivity are explained and the essence of adaptivity as a new basic methodological approach in cartography is stressed. However, in this paper mainly the need and potential of adaptation methods in the realm of mobile cartography are emphasised. The objective is to shift the focus from LBS to Context Based Services where the service is tailored to the current usage situation. Methodologically the adaptation occurs on different levels: content, technology, user interface, and presentation form. We will put emphasis on the adaptation of the presentation form and demonstrate how to use Scalable Vector Graphics (SVG), an open XML-based vector format, for delivering adapted content to mobile users. SVG seems well suited for the goal of presenting dynamic and adapted geoinformation content to mobile users, since it offers several useful features for this task. An analysis of items in the map design process that can be adapted is followed by a discussion of some adaptation methods. These methods will be implemented in a web service framework. The adaptation methods should fit in as adapters between geoinformation and visualisation. For different usage situations, different adapters will be designed. To illustrate the rather theoretical concept sketched in the first part, we will present a scenario highlighting possible geoinformation usage and its relation to everyday activities. Based on that scenario a situation analysis is performed identifying the relevant parameters for the adaptation process. A small demo example illustrates the possibilities of a geovisualisation web service for generating different visualisations. This part will show the server side generation of SVG documents depending on the current user category …