[show abstract][hide abstract] ABSTRACT: Ontologies play a key role in Semantic Web research. A common use of ontologies in Semantic Web is to enrich the current Web
resources with some well-defined meaning to enhance the search capabilities of existing web searching systems. This paper
reports on how ontologies developed in the EU Semantic Web project SPIRIT are used to support retrieval of documents that
are considered to be spatially relevant to users’ queries. The query expansion techniques presented in this paper are based
on both a domain and a geographical ontology. The proposed techniques are distinguished from conventional ones in that a query
is expanded by derivation of its geographical query footprint. The techniques are specially designed to resolve a query (such
as castles near Edinburgh) that involves spatial terms (e.g. Edinburgh) and fuzzy spatial relationships (e.g. near) that qualify the spatial terms. Various factors are taken into account to support intelligent expansion of a spatial query,
including, spatial terms as encoded in the geographical ontology, non-spatial terms as encoded in the domain ontology, as
well as the semantics of the spatial relationships and their context of use. Some experiments have been carried out to evaluate
the performance of the proposed techniques using sample realistic ontologies.
KeywordsOntology-Semantic Web-Spatial Search-Query Expansion
[show abstract][hide abstract] ABSTRACT: The SPIRIT search engine provides a test bed for the development of web search technology that is specialised for access to geographical information. Major components include the user interface, a geographical ontology, maintenance and retrieval functions for a test collection of web documents, textual and spatial indexes, relevance ranking and metadata extraction. Here we summarise the functionality and interaction between these components before focusing on the design of the geo-ontology and the development of spatio-textual indexing methods. The geo-ontology supports functionality for disambiguation, query expansion, relevance ranking and metadata extraction. Geographical place names are accompanied by multiple geometric footprints and qualitative spatial relationships. Spatial indexing of documents has been integrated with text indexing through the use of spatio-textual keys in which terms are concatenated with spatial cells to which they relate. Preliminary experiments demonstrate considerable performance benefits when compared with pure text indexing and with text indexing followed by a spatial filtering stage.
[show abstract][hide abstract] ABSTRACT: A geo-ontology has a key role to play in the development of a spatially aware search engine, with regard to providing support for query disambiguation, query term expansion, relevance ranking and web resource annotation. This paper reviews those functions and identifies the challenges arising in the construction and maintenance of such an ontology. Two current contenders for the representation of the geo-ontology are GML, a specific markup language for geographic domains and OWL, a generic ontology representation language. Both languages are used to model the geo-ontology designed for supporting web retrieval of geographic concepts. The powers and limitations of the languages are identified. In particular, the paper highlights the lack of representation and reasoning abilities for different types of rules needed for supporting the geo-ontology.
[show abstract][hide abstract] ABSTRACT: All aspects of human activity are rooted in geographic space in some respect. As a consequence, many web re- sources include references to geographic context. In order to assist in recognising spatial terms employed in a query, it is proposed to use a geographical ontology. A geo-ontology play a key role in the development of spatially-aware search engine, with regards to providing support for query disam- biguation, query expansion, relevance ranking and web re- source annotation. This paper describes the geo-ontology designed for the SPIRIT system, before focussing on the problem of integrating multiple datasets for constructing such an ontology. Similarity checking of datasets is an es- sential step in the process of integration. The validity and effect of the different measures are studied by building a prototype geo-ontology utilising different datasets. The ex- perimental results obtained confirmed the effect of quality of the datasets and the importance of the flexibility of the technique proposed for adjusting the similarity measures to handle such an effect.
IASTED International Conference on Databases and Applications, part of the 23rd Multi-Conference on Applied Informatics, Innsbruck, Austria, February 14-16, 2005; 01/2005
[show abstract][hide abstract] ABSTRACT: Constraints represent a class of business rules that describe the conditions under which an organisation operates. It is common that organisations implement a large number of constraints in their supporting information systems. To remain competitive in today's ever-changing business environment, organisations are increasingly recognising the ability to evolve the implemented constraints timely and correctly. While many techniques have been proposed to assist constraint specification and enforcement in information systems, little has been done so far to help constraint evolution. In this paper, we introduce a form of constraint analysis that is particularly geared towards constraint evolution. More specifically, we propose several algorithms for determining which constraints collectively restrict a specified set of business objects, and we study their performance. Since the constraints contained in an information system are typically in large quantities and tend to be fragmented during implementation, this type of analysis is desirable and valuable in the process of their evolution.
[show abstract][hide abstract] ABSTRACT: A geo-ontology has a key role to play in the development of a spatially-aware search engine, with regard to providing support
for query disambiguation, query term expansion, relevance ranking and web resource annotation. This paper reviews these functions,
discusses the user requirements which influence the design of the ontology, with regard to different types of query and fundamental
spatial concepts, before presenting a base model for a geographical ontology which will provide a foundation for subsequent
implementation as well as experimentation with alternative ontology models. The report also reviews various ontology languages
available for expressing ontologies and give examples for encoding the geo-ontology in them.
On The Move to Meaningful Internet Systems 2003: CoopIS, DOA, and ODBASE - OTM Confederated International Conferences, CoopIS, DOA, and ODBASE 2003, Catania, Sicily, Italy, November 3-7, 2003; 01/2003
[show abstract][hide abstract] ABSTRACT: Constraints are a class of business rules that many organisations implement in their information systems. However, it is common
that many implemented constraints do not get documented. This has led researchers to consider how to recover constraints from
implementations. In this paper, we consider the problem of how to analyse the set of constraints extracted from legacy systems.
More specifically, we introduce an algorithm for determining which constraints are related according to some criteria. Since
constraints are typically fragmented during their implementation, the ability to determine a set of related constraints is
useful and important to the comprehension of extracted constraints.
[show abstract][hide abstract] ABSTRACT: Constraints are a class of business rules that most information systems implement. However, due to sta. turnover and lackof
documentation, precise knowledge of what constraints are enforced by a system is often not available. This can seriously hinder
an organisation’s ability to understand the data stored in its systems, and to evolve the systems to implement new business
policies. To help the situation, researchers have considered how to extract constraints out of legacy systems. While some
powerful methods have been proposed for identifying constraints in application programs, little has been done so far to help
users to comprehend the recovered constraints. To step up research in this direction, we study in this paper how the recovered
constraints should be represented, so that they can be analysed, processed and then presented to the user in a comprehensible
manner. We introduce a representation language that offers a balance between expressiveness, comprehensibility and reasoning
power in handling the recovered constraints.
[show abstract][hide abstract] ABSTRACT: A business rule is a statement that defines or constrains some
aspects of a business. There has been a growing interest in developing
techniques to support the extraction of business rules buried in legacy
systems. However, little has been done so far to help understand the
semantics of extracted business rules. We propose a framework to support
the comprehension of business rules extracted from legacy systems. The
framework consists of two levels: a representation level and a
presentation level. At the representation level, we proposed a language,
BRL, to express business rules. We also perform logical inferences over
the set of business rules at this level. This helps to recover some
properties that may not be explicitly available from the extracted
business rules, but are essential to their understanding by users. The
presentation level, on the other hand, is concerned with how to convey
the semantics of business rules to different users. We believe that the
expressiveness and reasoning power of our proposed approach
significantly improve previous techniques in helping users to comprehend
extracted business rules
Database and Expert Systems Applications, 2001. Proceedings. 12th International Workshop on; 02/2001
[show abstract][hide abstract] ABSTRACT: A data-intensive program is one in which much of the complexity and design effort is centred around data definition and manipulation.
Many organisations have substantial investment in data design (data structures and constraints) coded in data intensive programs.
While there is a rich collection of techniques that can extract data design from database schemas, the extraction of data
design from data intensive programs is still largely an unsolved problem. In this paper, we propose a query-based approach
to this problem. Our approach allows users (maintainers or reverse engineers) to express a complex extraction task as a sequence
of queries over the source program. Unlike conventional techniques, which are designed for extracting a specific aspect of
a data design, our approach gives the user the control over what to extract and how it may be extracted in an exploratory
manner. Given the variety of coding styles used in data intensive programs, we believe that the exploratory feature of our
approach represents a plausible way forward for extracting data design from data intensive programs. We demonstrate the usefulness
of our approach with a number of examples.
Advanced Information Systems Engineering, 13th International Conference, CAiSE 2001, Interlaken, Switzerland, June 4-8, 2001, Proceedings; 01/2001