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73
XQL and Proximal Nodes
, 2000
"... We consider the recently proposed XQL language, which is designed to query XML documents by content and structure. We show that an already existing model, namely "Proximal Nodes", is the only one that addresses all the complex querying operations defined by XQL and that suggests an efficie ..."
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Cited by 15 (1 self)
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We consider the recently proposed XQL language, which is designed to query XML documents by content and structure. We show that an already existing model, namely "Proximal Nodes", is the only one that addresses all the complex querying operations defined by XQL and that suggests an efficient implementation for them.
Multivalued Dependencies in XML
- IN 20TH BRITISH NATIONAL CONFERENCE ON DATABASES (BNCOD
, 2003
"... Functional dependencies (FDs) and multivalued dependencies (MVDs) play a fundamental role in relational databases where they provide semantics for the data and at the same time are the foundation for database design. Since XML documents are closely coupled with relational databases in that XML do ..."
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Cited by 13 (4 self)
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Functional dependencies (FDs) and multivalued dependencies (MVDs) play a fundamental role in relational databases where they provide semantics for the data and at the same time are the foundation for database design. Since XML documents are closely coupled with relational databases in that XML documents are typically exported and imported from relational databases, the study of FDs and MVDs in XML is of fundamental significance in XML research. In this paper we investigate the issue of defining multivalued dependencies in XML, a topic which to the best of our knowledge has not been previously investigated. We define multivalued dependencies in XML (XMVDs) and justify our definition by proving that, for a very general class of mappings from relations to XML, a relation satisfies an MVD if and only if the corresponding XML document satisfies the corresponding XMVD. Thus our definition of a XMVD in a XML document is a natural extension of the definition of a MVD in relations.
Functional Dependencies for XML
- IN FIFTH ASIAN PACIFIC WEB CONFERENCE
, 2003
"... In this paper we address the problem of how to extend the definition of functional dependencies (FDs) in incomplete relations to XML documents. An incomplete relation is said to strongly satisfy a FD if every completion of the relation, obtained by replacing all null values by data values, satis ..."
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Cited by 13 (4 self)
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In this paper we address the problem of how to extend the definition of functional dependencies (FDs) in incomplete relations to XML documents. An incomplete relation is said to strongly satisfy a FD if every completion of the relation, obtained by replacing all null values by data values, satisfies the FD in the ordinary sense. We propose a syntactic definition of strong FD satisfaction in a XML document (called a XFD) and then justify it by proving that for a very general class of mappings of a relation into a XML document, a relation strongly satisfies a unary FD if and only if the XML document also strongly satisfies the equivalent XFD.
Personalizing Interactions with Information Systems
- in Advances in Computers
, 2002
"... Personalization constitutes the mechanisms and technologies necessary to customize information access to the end-user. It can be defined as the automatic adjustment of information content, structure, and presentation tailored to the individual. In this chapter, we study personalization from the view ..."
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Cited by 13 (9 self)
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Personalization constitutes the mechanisms and technologies necessary to customize information access to the end-user. It can be defined as the automatic adjustment of information content, structure, and presentation tailored to the individual. In this chapter, we study personalization from the viewpoint of personalizing interaction. The survey covers mechanisms for information-finding on the web, advanced information retrieval systems, dialogbased applications, and mobile access paradigms. Specific emphasis is placed on studying how users interact with an information system and how the system can encourage and foster interaction. This helps bring out the role of the personalization system as a facilitator which reconciles the user's mental model with the underlying information system's organization. Three tiers of personalization systems are presented, paying careful attention to interaction considerations. These tiers show how progressive levels of sophistication in interaction can be achieved. The chapter also surveys systems support technologies and niche application domains.
Multivalued Dependencies and a 4NF for XML
- In 15th International Conference on Advanced Information Systems Engineering (CAISE
, 2002
"... While providing syntactic flexibility, XML provides little semantic content and so the study of integrity constraints in XML plays an important role in helping to improve the semantic expressiveness of XML. Functional dependencies (FDs) and multivalued dependencies (MVDs) play a fundamental role ..."
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Cited by 12 (8 self)
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While providing syntactic flexibility, XML provides little semantic content and so the study of integrity constraints in XML plays an important role in helping to improve the semantic expressiveness of XML. Functional dependencies (FDs) and multivalued dependencies (MVDs) play a fundamental role in relational databases where they provide semantics for the data and at the same time are the foundation for database design. Since XML documents are closely coupled with relational databases in that XML documents are typically exported and imported from relational databases, the study of FDs and MVDs in XML is of fundamental significance in XML research. In this paper we define multivalued dependencies in XML (XMVDs). We then propose a normal form for XML documents in the presence of XMVDs and justify our normal form by showing that it ensures the elimination of redundancy.
Program transformations for information personalization
, 2004
"... Personalization constitutes the mechanisms necessary to automatically customize information content, structure, and presentation to the end-user to reduce information overload. Unlike traditional approaches to personalization, the central theme of our approach is to model a website as a program and ..."
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Cited by 11 (10 self)
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Personalization constitutes the mechanisms necessary to automatically customize information content, structure, and presentation to the end-user to reduce information overload. Unlike traditional approaches to personalization, the central theme of our approach is to model a website as a program and conduct website transformation for personalization by program transformation (e.g., partial evaluation, program slicing). The goal of this paper is study personalization through a program transformation lens, and develop a formal model, based on program transformations, for personalized interaction with hierarchical hypermedia. The specific research issues addressed involve identifying and developing program representations and transformations suitable for classes of hierarchical hypermedia, and providing supplemental interactions for improving the personalized experience. The primary form of personalization discussed is out-of-turn interaction – a technique which empowers a user navigating a hierarchical website to postpone clicking on any of the hyperlinks presented on the current page and, instead, communicate the
Unlocking keys for XML trees
- ICDT 2007. LNCS
, 2007
"... We review key constraints in the context of XML as introduced by Buneman et al. We show that one of the proposed inference rules is not sound in general, and the axiomatisation proposed for XML keys is incomplete even if key paths are simple. Therefore, the axiomatisation and also the implication pr ..."
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Cited by 11 (6 self)
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We review key constraints in the context of XML as introduced by Buneman et al. We show that one of the proposed inference rules is not sound in general, and the axiomatisation proposed for XML keys is incomplete even if key paths are simple. Therefore, the axiomatisation and also the implication problem for XML keys are still unsolved. We propose a set of inference rules that is indeed sound and complete for the implication of XML keys with simple key paths. Our completeness proof enables us to characterise the implication of XML keys in terms of the reachability problem of nodes in a digraph. This results in a quadratic time algorithm for deciding XML key implication, and shows that reasoning for XML keys is practically efficient.
Issues on Interoperability and Integration of Heterogeneous Geographical Data
- In III Brazilian Symposium on Geoinformatics - GEOINFO
, 2001
"... Abstract. The interoperability of information systems has been pursued for a long time by researchers and practi-tioners. It involves the exchange of information among different systems, and requires agreement on formats and application domain concepts. Interoperability may also encompass commonalit ..."
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Cited by 10 (0 self)
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Abstract. The interoperability of information systems has been pursued for a long time by researchers and practi-tioners. It involves the exchange of information among different systems, and requires agreement on formats and application domain concepts. Interoperability may also encompass commonality of user interaction and system behavior. One of the interoperability problems which has been investigated for over 20 years on different contexts is that of integration of heterogeneous data. However, even this fundamental and old problem is very hard to solve. The data integration problem may be considered from many perspectives and on increasing levels of complexity or abstraction. This paper reviews the literature about interoperability in general, and integration of heterogeneous geographical data in particular, presents several facets of the data integration problem, and some approaches to deal with them. 1
Integrating Diverse Information Management Systems: A Brief Survey
- IEEE Data Engineering Bulletin
, 2001
"... Most current information management systems can be classified into text retrieval systems, relational/object database systems, or semistructured/XML database systems. However, in practice, many applications data sets involve a combination of free text, structured data, and semistructured data. Henc ..."
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Cited by 9 (0 self)
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Most current information management systems can be classified into text retrieval systems, relational/object database systems, or semistructured/XML database systems. However, in practice, many applications data sets involve a combination of free text, structured data, and semistructured data. Hence, integration of different types of information management systems has been, and continues to be, an active research topic. In this paper, we present a short survey of prior work on integrating and inter-operating between text, structured, and semistructured database systems. We classify existing literature based on the kinds of systems being integrated and the approach to integration. Based on this classification, we identify the challenges and the key themes underlying existing work in this area.
