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Qualitative Spatial Representation and Reasoning: An Overview
- FUNDAMENTA INFORMATICAE
, 2001
"... The paper is a overview of the major qualitative spatial representation and reasoning techniques. We survey the main aspects of the representation of qualitative knowledge including ontological aspects, topology, distance, orientation and shape. We also consider qualitative spatial reasoning inclu ..."
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Cited by 264 (18 self)
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The paper is a overview of the major qualitative spatial representation and reasoning techniques. We survey the main aspects of the representation of qualitative knowledge including ontological aspects, topology, distance, orientation and shape. We also consider qualitative spatial reasoning including reasoning about spatial change. Finally there is a discussion of theoretical results and a glimpse of future work. The paper is a revised and condensed version of [33, 34].
Spherical Topological Relations
, 2005
"... Analysis of global geographic phenomena requires non-planar models. In the past, models for topological relations have focused either on a two-dimensional or a three-dimensional space. When applied to the surface of a sphere, however, neither of the two models suffices. For the two-dimensional plan ..."
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Cited by 152 (22 self)
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Analysis of global geographic phenomena requires non-planar models. In the past, models for topological relations have focused either on a two-dimensional or a three-dimensional space. When applied to the surface of a sphere, however, neither of the two models suffices. For the two-dimensional planar case, the eight binary topological relations between spatial regions are well known from the 9-intersection model. This paper systematically develops the binary topological relations that can be realized on the surface of a sphere. Between two regions on the sphere there are three binary relations that cannot be realized in the plane. These relations complete the conceptual neighborhood graph of the eight planar topological relations in a regular fashion, providing evidence for a regularity of the underlying mathematical model. The analysis of the algebraic compositions of spherical topological relations indicates that spherical topological reasoning often provides fewer ambiguities than planar topological reasoning. Finally, a comparison with the relations that can be realized for one-dimensional, ordered cycles draws parallels to the spherical topological relations.
Query Processing in Spatial-Query-by-Sketch
- Journal of Visual Languages and Computing
, 1997
"... Spatial-Query-by-Sketch is the design of a query language for geographic information systems. It allows a user to formulate a spatial query by drawing the desired configuration with a pen on a touch-sensitive computer screen and translates this sketch into a symbolic representation that can the proc ..."
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Cited by 95 (9 self)
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Spatial-Query-by-Sketch is the design of a query language for geographic information systems. It allows a user to formulate a spatial query by drawing the desired configuration with a pen on a touch-sensitive computer screen and translates this sketch into a symbolic representation that can the processed against a geographic database. Since the configurations queried usually do not match exactly the sketch, it is necessary to relax the spatial constraints drawn. This paper describes the representation of a sketch and outlines the design of the constraint relaxation methods used during query processing.
Qualitative Spatial Representation and Reasoning
- An Overview”, Fundamenta Informaticae
, 2001
"... The need for spatial representations and spatial reasoning is ubiquitous in AI – from robot planning and navigation, to interpreting visual inputs, to understanding natural language – in all these cases the need to represent and reason about spatial aspects of the world is of key importance. Related ..."
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Cited by 71 (10 self)
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The need for spatial representations and spatial reasoning is ubiquitous in AI – from robot planning and navigation, to interpreting visual inputs, to understanding natural language – in all these cases the need to represent and reason about spatial aspects of the world is of key importance. Related fields of research, such as geographic information science
Comparing Geospatial Entity Classes: An Asymmetric and Context-Dependent Similarity Measure
- International Journal of Geographical Information Science
, 2004
"... Semantic similarity plays an important role in geographic information systems as it supports the identification of objects that are conceptually close, but not identical. Similarity assessments are particularly important for retrieval of geospatial data in such settings as digital libraries, heterog ..."
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Cited by 59 (1 self)
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Semantic similarity plays an important role in geographic information systems as it supports the identification of objects that are conceptually close, but not identical. Similarity assessments are particularly important for retrieval of geospatial data in such settings as digital libraries, heterogeneous databases, and the World Wide Web. Although some computational models for semantic similarity assessment exist, these models are typically limited by their inability to handle such important cognitive properties of similarity judgments as their inherent asymmetry and their dependence on context. This paper defines the Matching-Distance Similarity Measure (MDSM) for determining semantic similarity among spatial entity classes, taking into account the distinguishing features of these classes (parts, functions, and attributes) and their semantic interrelations (is-a and part-whole relations). A matching process is combined with a semantic-distance calculation to obtain asymmetric values of similarity that depend on the degree of generalization of entity classes. MDSM's matching process is also driven by contextual considerations, where the context determines the relative importance of distinguishing features. Based on a human-subject experiment, MDSM results correlate well with people's judgments of similarity. When contextual information is used for determining the importance of distinguishing features, this correlation increases; however, the major component of the correlation between MDSM results and people's judgments is due to a detailed definition of entity classes.
Metric Details for Natural-Language Spatial Relations
- ACM Transactions on Information Systems
, 1998
"... Spatial relations often are desired answers that a geographic information system (GIS) should generate in response to a users query. Current GISs provide only rudimentary support for processing and interpreting natural-language-like spatial relations, because their models and representations are pri ..."
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Cited by 44 (4 self)
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Spatial relations often are desired answers that a geographic information system (GIS) should generate in response to a users query. Current GISs provide only rudimentary support for processing and interpreting natural-language-like spatial relations, because their models and representations are primarily quantitative, while natural-language spatial relations are usually dominated by qualitative properties. Studies of the use of spatial relations in natural language showed that topology accounts for a significant portion of the geometric properties. This paper develops a formal model that captures metricdetails for the description of natural-language spatial relations. The metric details are expressed as refinements of the categories identified by the 9intersection, a model for topological spatial relations, and provide a more precise measure than does topology alone as to whether a geometric configuration matches with a spatial term or not. Similarly, these measures help in identifying the spatial term that describes a particular configuration. Two groups of metric details are derived: splitting ratios as the normalized values of lengths and areas of intersections; and closeness measures as the normalized distances between disjoint object parts. The resulting model of topological and metric properties was calibrated for sixty-four spatial terms in English, providing values for the best fit as well as value ranges for the significant parameters of each term. Three examples demonstrate how the framework and its calibrated values are used to determine the best spatial term for a relationship between two geometric objects.
Querying by Spatial Structure
, 1998
"... : Structural queries constitute a special form of content-based retrieval where the user specifies a set of spatial constraints among query variables and searches for all configurations of actual objects that (totally or partially) match these constraints. Processing of such queries can be though ..."
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Cited by 32 (9 self)
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: Structural queries constitute a special form of content-based retrieval where the user specifies a set of spatial constraints among query variables and searches for all configurations of actual objects that (totally or partially) match these constraints. Processing of such queries can be thought of as a general form of spatial joins, i.e., instead of pairs, the result consists of n-tuples of objects, where n is the number of query variables. In this paper we propose a flexible framework which permits the representation of configurations in different resolution levels and supports the automatic derivation of similarity measures. We subsequently describe three algorithms for structural query processing which integrate constraint satisfaction with spatial indexing. For each algorithm we apply several optimization techniques and experimentally evaluate performance using real data. Abstract Tracking Number: 628 Correspondence should be addressed to Dimitris Papadias. Tel: ++85...
Sim-dl: Towards a semantic similarity measurement theory for the description logic ALCNR in geographic information retrieval
- SeBGIS 2006, OTM Workshops 2006. Volume 4278 of Lecture Notes in Computer Science
, 2006
"... Abstract. Similarity measurement theories play an increasing role in GIScience and especially in information retrieval and integration. Existing feature and geometric models have proven useful in detecting close but not identical concepts and entities. However, until now none of these theories are a ..."
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Cited by 30 (9 self)
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Abstract. Similarity measurement theories play an increasing role in GIScience and especially in information retrieval and integration. Existing feature and geometric models have proven useful in detecting close but not identical concepts and entities. However, until now none of these theories are able to handle the expressivity of description logics for various reasons and therefore are not applicable to the kind of ontologies usually developed for geographic information systems or the upcoming geospatial semantic web. To close the resulting gap between available similarity theories on the one side and existing ontologies on the other, this paper presents ongoing work to develop a context-aware similarity theory for concepts specified in expressive description logics such as ALCNR. 1
Processing Fuzzy Spatial Queries: A Configuration Similarity Approach
- International Journal of Geographic Information Science
, 1998
"... . Increasing interest for configuration similarity is currently developing in the context of Digital Libraries, Spatial Databases and Geographical Information Systems. The corresponding queries retrieve all database configurations that match an input description (e.g., "find all configurations ..."
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Cited by 23 (1 self)
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. Increasing interest for configuration similarity is currently developing in the context of Digital Libraries, Spatial Databases and Geographical Information Systems. The corresponding queries retrieve all database configurations that match an input description (e.g., "find all configurations where an object x 0 is about 5km northeast of another x 1 , which, in turn, is inside object x 2 "). This paper introduces a framework for configuration similarity that takes into account all major types of spatial constraints (topological, direction, distance). We define appropriate fuzzy similarity measures for each type of constraint to provide flexibility and allow the system to capture real-life needs. Then we apply pre-processing techniques to explicate constraints in the query, and present algorithms that effectively solve the problem. Extensive experimental results demonstrate the applicability of our approach to images and queries of considerable size. 1. INTRODUCTION As opposed to visu...
Voronoi-Based Region Approximation for Geographical Information Retrieval With Gazetteers
, 2001
"... Gazeteers and geographical thesauri can be regarded as parsimonious spatial models that associate geographical location with place names and encode some semantic relations between the names. They are of particular value in processing information retrieval requests in which the user employs place nam ..."
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Cited by 21 (5 self)
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Gazeteers and geographical thesauri can be regarded as parsimonious spatial models that associate geographical location with place names and encode some semantic relations between the names. They are of particular value in processing information retrieval requests in which the user employs place names to specify geographical context. Typically the geometric locational data in a gazetteer are confined to a simple footprint in the form of a centroid or a minimum bounding rectangle, both of which can be used to link to a map but are of limited value in determining spatial relationships. Here we describe a Voronoi diagram method for generating approximate regional extents from sets of centroids that are respectively inside and external to a region. The resulting approximations provide measures of areal extent and can be used to assist in answering geographical queries by evaluating spatial relationships such as distance, direction and common boundary length. Preliminary experimental evaluations of the method have been performed in the context of a semantic modelling system that combines the centroid data with hierarchical and adjacency relations between the associated place names.
