The delta/[symbol: see text] texel pair represents a dilemma in texture discrimination because, despite having the same component orientations, discrimination is still possible (Julesz, 1981), showing a performance asymmetry. Other possible element properties that could influence this task are line terminations, closure, and the size of these elements. We found that line terminators are critica...

We quantified and compared the effect of element spacing on contour integration between the achromatic (Ach), red-green (RG), and blue-yellow (BY) mechanisms. The task requires the linking of orientation across space to detect a contour in a stimulus composed of randomly oriented Gabor elements (1.5 cpd, sigma = 0.17 deg), measured using a temporal 2AFC method. A contour of ten elements was pas...

A lattice L is spatial if every element of L is a join of completely join-irreducible elements of L (points), and strongly spatial if it is spatial and the minimal coverings of completely join-irreducible elements are well-behaved. Herrmann, Pickering, and Roddy proved in 1994 that every modular lattice can be embedded, within its variety, into an algebraic and spatial lattice. We extend this r...

The paper shows how to give a direct discrete formulation of the wave equation starting directly from physical laws, i.e. without passing through differential formulation. Using global variables instead of scalar and vector field functions, a close link between global variables and spatial and temporal elements immediately appears. A preliminary classification of physical variables into three c...

Depictions, such as maps, that portray visible things are ancient whereas graphics, such as charts and diagrams, that portray things that are inherently not visible, are relatively modern inventions. An analysis of historical and developmental graphic inventions suggests that they convey meaning by using elements and space naturally. Elements are based on likenesses, "figures of depiction" and ...

We present a study on connection errors in networks of linear features and methods of error detection. We model networks with special connection specifications as networks with hierarchically connected features and define errors considering the spatial relationships and the functionality of the network elements. A general definition of the problem of the detection of connection errors which tak...

There is a potential theoretical problem in the established framework of market-area and supply-area analysis when both approaches are investigated in an integrated framework with respect to firm location. It is argued that the mechanism of the problem is illustrated by insufficient inclusions of the notion of internal and external economies. The alternative model formulates the spatial duality...

The national western spatial data quality check method based on entity and evaluation method based on the cloud theory and rough set have been put forward according to the National Western Surveying and Mapping Project on 1:50000 Topological Maps Blank Area. In the first place, national western spatial data quality problem is analyzed and possible quality problems are described. Secondly, a dig...