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71
Spatial representation and reasoning.
- In Intelligent Systems: Concepts and Applications,
, 2002
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A qualitative trajectory calculus and the composition of its relations
- Proc. of GeoS
, 2005
"... Abstract. Continuously moving objects are prevalent in many domains. Although there have been attempts to combine both spatial and temporal relationships from a reasoning, a database, as well as from a logical perspective, the question remains how to describe motion adequately within a qualitative c ..."
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Abstract. Continuously moving objects are prevalent in many domains. Although there have been attempts to combine both spatial and temporal relationships from a reasoning, a database, as well as from a logical perspective, the question remains how to describe motion adequately within a qualitative calculus. In this paper, a Qualitative Trajectory Calculus (QTC) for representing and reasoning about moving objects in two dimensions is presented. Specific attention is given to a central concept in qualitative reasoning, namely the composition of relations. The so-called composition-rule table is presented, which is a neat way of representing a composition table. The usefulness of QTC and the composition-rule table is illustrated by an example. 1
Spatial Logics with Connectedness Predicates
- LOGICAL METHODS IN COMPUTER SCIENCE
, 2010
"... We consider quantifier-free spatial logics, designed for qualitative spatial representation and reasoning in AI, and extend them with the means to represent topological connectedness of regions and restrict the number of their connected components. We investigate the computational complexity of thes ..."
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Cited by 10 (3 self)
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We consider quantifier-free spatial logics, designed for qualitative spatial representation and reasoning in AI, and extend them with the means to represent topological connectedness of regions and restrict the number of their connected components. We investigate the computational complexity of these logics and show that the connectedness constraints can increase complexity from NP to PSpace, ExpTime and, if component counting is allowed, to NExpTime.
Feature ontologies for the explicit representation of shape semantic
- International Journal of Computer Applications in Technology 2005
, 2005
"... Models and methods for representing and processing shape semantics ..."
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Cited by 9 (0 self)
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Models and methods for representing and processing shape semantics
Stonian p-ortholattices: A new approach to the mereotopology RT0
- ARTIFICIAL INTELLIGENCE
, 2009
"... This paper gives an isomorphic representation of the subtheories RT − , RT − EC, and RT of Asher and Vieu’s first-order ontology of mereotopology RT0. It corrects and extends previous work on the representation of these mereotopologies. We develop the theory of p-ortholattices – lattices that are bo ..."
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Cited by 7 (6 self)
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This paper gives an isomorphic representation of the subtheories RT − , RT − EC, and RT of Asher and Vieu’s first-order ontology of mereotopology RT0. It corrects and extends previous work on the representation of these mereotopologies. We develop the theory of p-ortholattices – lattices that are both orthocomplemented and pseudocomplemented – and show that the identity (x·y) ∗ = x ∗ +y ∗ defines the natural class of Stonian p-ortholattices. Equivalent conditions for a p-ortholattice to be Stonian are given. The main contribution of the paper consists of a representation theorem for RT − as Stonian p-ortholattices. Moreover, it is shown that the class of models of RT − EC is isomorphic to the non-distributive Stonian p-ortholattices and a representation of RT is given by a set of four algebras of which one need to be a subalgebra of the present model. As corollary we obtain that Axiom (A11) – existence of two externally connected regions – is in fact a theorem of the remaining axioms of RT.
2008a. Counterparts in Language and Space – Similarity and S-Connection
- Formal Ontology in Information Systems (FOIS 2008
"... Abstract We aim to combine the semantics of spatial natural language specified as a linguistically motivated ontology, the Generalized Upper Model, with spatial log-ics or ontologies that specify space according to certain conceptualisations, based on regions, shapes, orientations, distances, or obj ..."
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Cited by 7 (5 self)
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Abstract We aim to combine the semantics of spatial natural language specified as a linguistically motivated ontology, the Generalized Upper Model, with spatial log-ics or ontologies that specify space according to certain conceptualisations, based on regions, shapes, orientations, distances, or object properties. Such combinations, however, introduce uncertainties of various kinds, caused by different levels of detail in the definition of one of the spatial ontologies, under-specifications within parts of an ontology, or different viewpoints of the topics the ontologies address. To model these problems formally, we extend the combination technique of E-connections by adding (heterogeneous) similarity measures. Local similarity compares objects within one domain, whilst comparing objects across domains leads to similarity measures that are motivated by and based on counterpart-theoretic semantics. The new formalism is called S-connection.
Efficient Extraction and Representation of Spatial Information from Video Data
"... Vast amounts of video data are available on the web and are being generated daily using surveillance cameras or other sources. Being able to efficiently analyse and process this data is essential for a number of different applications. We want to be able to efficiently detect activities in these vid ..."
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Cited by 6 (4 self)
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Vast amounts of video data are available on the web and are being generated daily using surveillance cameras or other sources. Being able to efficiently analyse and process this data is essential for a number of different applications. We want to be able to efficiently detect activities in these videos or be able to extract and store essential information contained in these videos for future use and easy search and access. Cohn et al. (2012) proposed a comprehensive representation of spatial features that can be efficiently extracted from video and used for these purposes. In this paper, we present a modified version of this approach that is equally efficient and allows us to extract spatial information with much higher accuracy than previously possible. We present efficient algorithms both for extracting and storing spatial information from video, as well as for processing this information in order to obtain useful spatial features. We evaluate our approach and demonstrate that the extracted spatial information is considerably more accurate than that obtained from existing approaches. 1
The Egenhofer–Cohn Hypothesis or, Topological Relativity?
, 2013
"... In this chapter, we provide an overview of research on cognitively validating qualitative calculi, focusing on the region connection calculus (RCC) and Egenhofer’s intersection models (IM). These topological theories are often claimed to be foundational to spatial cognition, a concept we term the ..."
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Cited by 6 (2 self)
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In this chapter, we provide an overview of research on cognitively validating qualitative calculi, focusing on the region connection calculus (RCC) and Egenhofer’s intersection models (IM). These topological theories are often claimed to be foundational to spatial cognition, a concept we term the Egenhofer– Cohn Hypothesis. (The authors are aware of the limitations of the chosen title/ term. Neither Egenhofer nor Cohn necessarily support this claim in a strong form but they kindly agreed to have their names used here. Additionally, there are other approaches to topology, Cohn is the third author on the classic RCC paper, and Egenhofer published his work with co-authors. However, we feel that these two names best summarize the two most prominent topological theories in the spatial sciences.) We have been particularly interested in extending existing approaches into the realm of spatio-temporal representation and reasoning. We provide an overview on a series of experiments that we conducted to shed light on geographic event conceptualization and topology’s role in modeling and explaining cognitive
Full mereogeometries
- Journal of Philosophical Logic
, 2007
"... Abstract. We analyze and compare geometrical theories based on mereology (mereogeometries). Most theories in this area lack in formalization, and this prevents any systematic logical analysis. To overcome this problem, we concentrate on specific interpretations for the primitives and use them to iso ..."
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Abstract. We analyze and compare geometrical theories based on mereology (mereogeometries). Most theories in this area lack in formalization, and this prevents any systematic logical analysis. To overcome this problem, we concentrate on specific interpretations for the primitives and use them to isolate comparable models for each theory. Relying on the chosen interpretations, we introduce the notion of environment structure, that is, a minimal structure that contains a (sub)structure for each theory. In particular, in the case of mereogeometries, the domain of an environment structure is composed of particular subsets of Rn. The comparison of mereogeometrical theories within these environment structures shows dependencies among primitives and provides (relative) definitional equivalences. With one exception, we show that all the theories considered are equivalent in these environment structures. 1. Introduction. At the time Lobachevskii (1835
On the computational complexity of spatial logics with connectedness constraints
- PROCCEDINGS OF LPAR 2008
, 2008
"... We investigate the computational complexity of spatial logics extended with the means to represent topological connectedness and restrict the number of connected components. In particular, we show that the connectedness constraints can increase complexity from NP to PSpace, ExpTime and, if component ..."
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Cited by 6 (4 self)
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We investigate the computational complexity of spatial logics extended with the means to represent topological connectedness and restrict the number of connected components. In particular, we show that the connectedness constraints can increase complexity from NP to PSpace, ExpTime and, if component counting is allowed, to NExpTime.
