Abstract. This work addresses the problem of relaxing spatial constraints for pictorial queries having null answers in geographical databases. It fo-cuses on the polygon-polyline topological relationship and proposes a computational model which is based on the notions of Operator Concep

Abstract. This paper proposes and discusses an eXtended Pictorial Query Language (XPQL) for geographic data, and its possible use on the Web. This query language is mapped in Geographic Markup Language (GML 3.0), which is used for transport to the Web and storage of geographic information

visualizing semantics of query elements. Approximate queries rely on combined topological and geometrical constraints enhanced with relaxations and "don't cares" that are visualized through live animations. Keywords--- visual query systems, visual parsing, deductive GIS, constraints. 1

Today's methods for interacting with geographic information systems (GISs) and geographic databases are primarily aspatial, as they require users to deal with geographic data primarily through alphanumeric command languages. Spatial querying by typing a command in some spatial query language

, operators and spatial relations.Different granularities of the relations are presented in a hierarchical fashion for spatial constraints.The language framework and functions are described and examples are used to demonstrate its capabilities in representing different levels of queries, including spatial

and backchase

As wireless sensor networks continue to grow in size, we are faced with the prospect of emerging wireless networks with hundreds or thousands of nodes. Geographic routing algorithms are a promising alternative to tradition ad hoc routing algorithms in this new domain for point-to-point routing

if they were points”: Expressions like “Prague lies half-way between Vienna and Berlin ” or “The apartment is located quite between a train station, a tram stop, and a bus stop” involve not only topological relations, but also approximate geometric constructions that use extended geographic entities

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of con-cepts. This main goal is motivated by the basic fact, constituting also the main problem of KDD, that languages we may choose for knowledge description are incomplete. A fortiori, we have to describe concepts of interest (features, proper-ties, relations etc.) not completely but by means