Practical Exercises on Topographic Maps

Scree Representation on Topographic Maps

Scree patterns are an important element of mountain maps in Swiss style. The size and density of scree dots vary with the exposition towards a source of illumination, which makes the dots extremely labour intensive to map without specialized algorithms. This paper identifies design principles for the symbolisation of scree fields on mountain slopes and presents a digital method for the quick pl...

Topographic Maps

We call "natural" image any photograph of an outdoor or indoor scene taken by a standard camera. We discuss the physical generation process of natural images as a combination of occlusions, transparencies and contrast changes. This description ts to the phenomeno-logical description of Gaetano Kanizsa according to which visual perception tends to remain stable with respect to these basic operat...

Relational Topographic Maps

We introduce relational variants of neural topographic maps including the selforganizing map and neural gas, which allow clustering and visualization of data given in terms of a pairwise similarity or dissimilarity matrix. It is assumed that this matrix originates from an euclidean distance or dot product, respectively, however, the underlying embedding of points is unknown. One can equivalentl...

Exercises in Practical Physiology

Topology preservation in topographic maps

The construction of topographic models for fitting a model to the data set requires selection of appropriate values for its parameters. Since the parameters control the flexibility of the model, the generalization problem is directly related to parameter selection. This paper addresses this problem, using a novel criterion for monitoring topographic maps in which the key observation is that we ...