16,025 research outputs found
Some issues in data model mapping
Numerous data models have been reported in the literature since the early 1970's. They have been used as database interfaces and as conceptual design tools. The mapping between schemas expressed according to the same data model or according to different models is interesting for theoretical and practical purposes. This paper addresses some of the issues involved in such a mapping. Of special interest are the identification of the mapping parameters and some current approaches for handling the various situations that require a mapping
Schema architecture and their relationships to transaction processing in distributed database systems
We discuss the different types of schema architectures which could be supported by distributed database systems, making a clear distinction between logical, physical, and federated distribution. We elaborate on the additional mapping information required in architecture based on logical distribution in order to support retrieval as well as update operations. We illustrate the problems in schema integration and data integration in multidatabase systems and discuss their impact on query processing. Finally, we discuss different issues relevant to the cooperation (or noncooperation) of local database systems in a heterogeneous multidatabase system and their relationship to the schema architecture and transaction processing
A universal ontology-based approach to data integration
One of the main problems in building data integration systems is that of semantic integration. It has been acknowledged that the problem would not exist if all systems were developed using the same global schema, but so far, such global schema has been considered unfeasible in practice. However, in our previous work, we have argued that given the current state-of-the-art, a global schema may be feasible now, and we have put forward a vision of a Universal Ontology (UO) that may be desirable, feasible, and viable. One of the reasons why the UO may be desirable is that it might solve the semantic integration problem. The objective of this paper is to show that indeed the UO could solve, or at least greatly alleviate, the semantic integration problem. We do so by presenting an approach to semantic integration based on the UO that requires much less effort than other approaches.Peer ReviewedPostprint (published version
A framework for utility data integration in the UK
In this paper we investigate various factors which prevent utility knowledge from being
fully exploited and suggest that integration techniques can be applied to improve the
quality of utility records. The paper suggests a framework which supports knowledge
and data integration. The framework supports utility integration at two levels: the
schema and data level. Schema level integration ensures that a single, integrated geospatial
data set is available for utility enquiries. Data level integration improves utility data
quality by reducing inconsistency, duplication and conflicts. Moreover, the framework
is designed to preserve autonomy and distribution of utility data. The ultimate aim of
the research is to produce an integrated representation of underground utility infrastructure
in order to gain more accurate knowledge of the buried services. It is hoped that
this approach will enable us to understand various problems associated with utility data,
and to suggest some potential techniques for resolving them
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
Automated syntactic mediation for Web service integration
As the Web Services and Grid community adopt Semantic Web technology, we observe a shift towards higher-level workflow composition and service discovery practices. While this provides excellent functionality to non-expert users, more sophisticated middleware is required to hide the details of service invocation and service integration. An investigation of a common Bioinformatics use case reveals that the execution of high-level workflow designs requires additional processing to harmonise syntactically incompatible service interfaces. In this paper, we present an architecture to support the automatic reconciliation of data formats in such Web Service worklflows. The mediation of data is driven by ontologies that encapsulate the information contained in heterogeneous data structures supplying a common, conceptual data representation. Data conversion is carried out by a Configurable Mediator component, consuming mappings between \xml schemas and \owl ontologies. We describe our system and give examples of our mapping language against the background of a Bioinformatics use case
Functorial Data Migration
In this paper we present a simple database definition language: that of
categories and functors. A database schema is a small category and an instance
is a set-valued functor on it. We show that morphisms of schemas induce three
"data migration functors", which translate instances from one schema to the
other in canonical ways. These functors parameterize projections, unions, and
joins over all tables simultaneously and can be used in place of conjunctive
and disjunctive queries. We also show how to connect a database and a
functional programming language by introducing a functorial connection between
the schema and the category of types for that language. We begin the paper with
a multitude of examples to motivate the definitions, and near the end we
provide a dictionary whereby one can translate database concepts into
category-theoretic concepts and vice-versa.Comment: 30 page
Evaluating musical software using conceptual metaphors
An open challenge for interaction designers is to find ways of designing software to enhance the ability of novices to perform tasks that normally require specialized domain expertise. This challenge is particularly demanding in areas such as music analysis, where complex, abstract, domain-specific concepts and notations occur. One promising theoretical foundation for this work involves the identification of conceptual metaphors and image schemas, found by analyzing discourse. This kind of analysis has already been applied, with some success, both to musical concepts and, separately, to user interface design. The present work appears to be the first to combine these hitherto distinct bodies of research, with the aim of devising a general method for improving user interfaces for music. Some areas where this may require extensions to existing method are noted.
This paper presents the results of an exploratory evaluation of Harmony Space, a tool for playing, analysing and learning about harmony. The evaluation uses conceptual metaphors and image schemas elicited from the dialogues of experienced musicians discussing the harmonic progressions in a piece of music. Examples of where the user interface supports the conceptual metaphors, and where support could be improved, are discussed. The potential use of audio output to support conceptual metaphors and image schemas is considered
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