UK utility data integration: overcoming schematic heterogeneity

In this paper we discuss syntactic, semantic and schematic issues which inhibit the integration of utility data in the UK. We then focus on the techniques employed within the VISTA project to overcome schematic heterogeneity. A Global Schema based architecture is employed. Although automated approaches to Global Schema definition were attempted the heterogeneities of the sector were too great. A manual approach to Global Schema definition was employed. The techniques used to define and subsequently map source utility data models to this schema are discussed in detail. In order to ensure a coherent integrated model, sub and cross domain validation issues are then highlighted. Finally the proposed framework and data flow for schematic integration is introduced

Understanding the Spatial Complexity in Landscape Narratives Through Qualitative Representation of Space

Narratives are the richest source of information about the human experience of place. They represent events and movement, both physical and conceptual, within time and space. Existing techniques in geographical text analysis usually incorporate named places with coordinate information. This is a serious limitation because many textual references to geography are ambiguous, non-specific, or relative. It is imperative but hard for a geographic information system to capture a text’s sense of place, an imprecise concept. This work aims to utilize qualitative spatial representation and natural language processing to allow representations of all three characteristics of place (location, locale, sense of place) as found in textual sources

Geospatial Semantics: Why, of What, and How?

Abstract. Why are notions like semantics and ontologies suddenly getting so much attention, within and outside geospatial information communities? The main reason lies in the componentization of Geographic Information Systems (GIS) into services, which are supposed to interoperate within and across these communities. Consequently, I look at geospatial semantics in the context of semantic interoperability. The paper clarifies the relevant notion of semantics and shows what parts of geospatial information need to receive semantic speci-fications in order to achieve interoperability. No attempt at a survey of ap-proaches to provide semantics is made, but a framework for solving interopera-bility problems is proposed in the form of semantic reference systems. Particular emphasis is put on the need and possible ways to ground geospatial semantics in physical processes and measurements. 1. Introduction: Wh

On the Skeleton of Stonian p-Ortholattices

Abstract. Boolean Contact Algebras (BCA) establish the algebraic counterpart of the mereotopolopy induced by the Region Connection Calculus (RCC). Similarly, Stonian p-ortholattices serve as a lattice theoretic version of the ontology RT − of Asher and Vieu. In this paper we study the relationship between BCAs and Stonian p-ortholattices. We show that the skeleton of every Stonian p-ortholattice is a BCA, and, conversely, that every BCA is isomorphic to the skeleton of a Stonian p-ortholattice. Furthermore, we prove the equivalence between algebraic conditions on Stonian p-ortholattices and the axioms C5, C6, and C7 for BCAs.

A qualitative account of discrete space

Abstract. Computations in geographic space are necessarily based on discrete versions of space, but much of the existing work on the foundations of GIS assumes a continuous infinitely divisible space. This is true both of quantitative approaches, using R n, and qualitative approaches using systems such as the Region-Connection Calculus (RCC). This paper shows how the RCC can be modified so as to permit discrete spaces by weakening Stell’s formulation of RCC as Boolean connection algebra to what we now call a connection algebra. We show how what was previously considered a problem—with atomic regions being parts of their complements—can be resolved, but there are still obstacles to the interplay between parthood and connection when there are finitely many regions. Connection algebras allow regions that are atomic and also regions that are boundaries of other regions. The modification of the definitions of the RCC5 and RCC8 relations needed in the context of a connection algebra are discussed. Concrete examples of connection algebras are provided by abstract cell complexes. In order to place our work in context we start with a survey of previous approaches to discrete space in GIS and related areas.