Martin Raubal

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Semantics constitutes the highest level on the communication ladder. The mutual understanding of terms makes it possible that information systems can communicate with people and among each other. Two opposing approaches to explaining the meaning of terms exist: a realist and a cognitive one. Many efforts for solving the so-called problem of semantic(More)
People navigating in unfamiliar environments rely on wayfinding directions, either given by people familiar with the place, or given by maps or wayfinding services. The essential role of landmarks in human route communication is well-known. However, mapping the human ability to select landmarks ad hoc for route directions to a computational model was never(More)
Researchers in the areas of human wayfinding, spatial cognition, computer science, and artificial intelligence have developed cognitively based computational models for wayfinding. These models focus primarily on learning a spatial environment and on the exploration of mental representations rather than the information needs for wayfinding. It is important(More)
Location-based services (LBS) assist people in decision-making during the performance of tasks in space and time. Current LBS support spatial and attribute queries, such as finding the nearest Italian restaurant from the current location of the user, but they are limited in their capacity to evaluate decision alternatives and to consider individual(More)
The modeling of concepts from a cognitive perspective is important for designing spatial information systems that interoperate with human users. Concept representations that are built using geometric and topological conceptual space structures are well suited for semantic similarity and concept combination operations. In addition, concepts that are more(More)
A user study was conducted to compare the performance of three methods for map navigation with mobile devices. These methods are joystick navigation, the dynamic peephole method without visual context, and the magic lens paradigm using external visual context. The joystick method is the familiar scrolling and panning of a virtual map keeping the device(More)
The analogy of Semantic Reference Systems proposed in (Kuhn in press) is being explored here with respect to the computational mechanisms it suggests. Semantic referencing, grounding in a semantic datum, semantic projection, and semantic transformation are defined and demonstrated through an implementation of a semantic reference system for a simple vehicle(More)