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eXtensible Markup Language (XML) data are data which are not necessarily constrained by a schema, XML is fast emerging as a standard for data representation and exchange on the world wide web, the ability to intelligently query XML data becomes increasingly important. Some XML graphical query languages for XML data have been proposed but they are either too complex or too limited in the power of expression and in their use. The purpose of this paper is to propose a recursive graphical query language for querying and restructuring XML data (RGQLX). The expressive power of RGQLX is comparable to Fixpoint. RGQLX language is a multi‐sorted graphical language integrating grouping, aggregate functions, nested queries and recursion.

The methodology emphasizes on RGQLX's development which is base of G‐XML data model syntax to express a wide variety of XML queries, ranging from simple selection, to expressive data transformations involving grouping, aggregation and sorting. RGQLX allows users to express recursive visual queries in an elegant manner. RGQLX has an operational semantics based on the annotated XML, which serves to express queries and data trees in form of XML. The paper presents an algorithm to achieve the matching between data and query trees after translating a query tree into annotated XML.

Developed and demonstrated were: a G‐XML model; recursive queries; annotated XML for the semantic operations and a matching algorithm.

The future research work on RGQLX language will be expanding it to include recursive aggregations.

The algorithms/approaches proposed can be easily integrated in any commercial product to enhance the performance of XML query languages.

The proposed work integrates various novel techniques for XML query syntax/semantic into a single language with a suitable matching algorithm. The power of this proposal is in the class of Fixpoint queries.

In the last two decades, a proliferation of business process management (BPM) modeling languages, standards and software systems has given rise to much confusion and obstacles to adoption. Since new BPM languages and notation terminologies were not well defined, duplicate features are common. This paper seeks to make sense of the myriad BPM standards, organising them in a classification framework, and to identify key industry trends.

An extensive literature review is conducted and relevant BPM notations, languages and standards are referenced against the proposed BPM Standards Classification Framework, which lists each standard's distinct features, strengths and weaknesses.

The paper is unaware of any classification of BPM languages. An attempt is made to classify BPM languages, standards and notations into four main groups: execution, interchange, graphical, and diagnosis standards. At the present time, there is a lack of established diagnosis standards. It is hoped that such a classification facilitates the meaningful adoption of BPM languages, standards and notations.

The paper differentiates BPM standards, thereby resolving common misconceptions; establishes the need for diagnosis standards; identifies the strengths and limitations of current standards; and highlights current knowledge gaps and future trends. Researchers and practitioners may wish to position their work around this review.

Currently, to the best of one's knowledge, such an overview and such an analysis of BPM standards have not so far been undertaken.

Information overload has led to a situation where users are swamped with too much information, resulting in difficulty sifting through material in search of relevant content. Aims to address this issue from the perspective of collaborative querying, an approach that helps users formulate queries by harnessing the collective knowledge of other searchers.

The design and implementation of the Query Graph Visualizer (QGV), a collaborative querying system which harvests and clusters previously issued queries to form query networks that represent related information needs are described. A preliminary evaluation of the QGV is also described in which a group of participants evaluated the usability and usefulness of the system by completing a set of tasks and a questionnaire based on Nielsen's heuristic evaluation technique.

In the QGV, a submitted query is matched to its closest cluster and a recursive algorithm is applied to find other related clusters, forming a query network. The queries in the network are explored in the QGV, helping users locate other queries that might meet their current information needs. The results of the evaluation suggest the usefulness and usability of the system. Participants could complete their assigned tasks using the QGV and positively rated the system in terms of usability.

The techniques described can be used to design information retrieval systems that learn from the trials and tribulations of other searchers and help users in their quest for relevant and quality information

The purpose of this paper is to introduce an expressive query language, called relational XML query language (RXQL), capable of dealing with heterogeneous Extensible Markup Language (XML) documents in data‐centric applications. In RXQL, data harmonization (i.e. the removal of heterogeneous factors from XML data) is integrated with typical data‐centric features (e.g. grouping, ordering, and aggregation).

RXQL is based on the XML relation representation, developed in the authors' previous work. This is a novel approach to unambiguously represent semistructured data relationally, which makes it possible in RXQL to manipulate XML data in a tuple‐oriented way, while XML data are typically manipulated in a path‐oriented way.

The user is able to describe the result of an RXQL query straightforwardly based on non‐XML syntax. The analysis of this description, through the mechanism developed in this paper, affords the automatic construction of the query result. This feature increases significantly the declarativeness of RXQL compared to the path‐oriented XML languages where the user needs to control the construction of the result extensively.

The authors' formal specification of the construction of the query result can be considered as an abstract implementation of RXQL.

RXQL is a declarative query language capable of integrating data harmonization seamlessly with other data‐centric features in the manipulation of heterogeneous XML data. So far, these kinds of XML query languages have been missing. Obviously, the expressive power of RXQL can be achieved by computationally complete XML languages, such as XQuery. However, these are not actual query languages, and the query formulation in them usually presupposes programming skills that are beyond the ordinary end‐user.

Estimating the sizes of query results and intermediate results is crucial to many aspects of query processing. All database systems rely on the use of cardinality estimates to choose the cheapest execution plan. In principle, the problem of cardinality estimation is more complicated in the Extensible Markup Language (XML) domain than the relational domain. The purpose of this paper is to present a novel framework for estimating the cardinality of XQuery expressions as well as their sub‐expressions. Additionally, this paper proposes a novel XQuery cardinality estimation benchmark. The main aim of this benchmark is to establish the basis of comparison between the different estimation approaches in the XQuery domain.

As a major innovation, the paper exploits the relational algebraic infrastructure to provide accurate estimation in the context of XML and XQuery domains. In the proposed framework, XQuery expressions are translated into an equivalent relational algebraic plans and then using a well defined set of inference rules and a set of special properties of the algebraic plan, this framework is able to provide high‐accurate estimation for XQuery expressions.

This paper is believed to be the first which provides a uniform framework to estimate the cardinality of more powerful XML querying capabilities using XQuery expressions as well as their sub‐expressions. It exploits the relational algebraic infrastructure to provide accurate estimation in the context of XML and XQuery domains. Moreover, the proposed framework can act as a meta‐model through its ability to incorporate different summarized XML structures and different histogram techniques which allows the model designers to achieve their targets by focusing their effort on designing or selecting the adequate techniques for them. In addition, this paper proposes benchmark for XQuery cardinality estimation systems. The proposed benchmark distinguishes itself from the other existing XML benchmarks in its focus on establishing the basis for comparing the different estimation approaches in the XML domain in terms of their accuracy of the estimations and their completeness in handling different XML querying features.

The current status of this proposed XQuery cardinality estimations framework does not support the estimation of the queries over the order information of the source XML documents and does not support non‐numeric predicates.

The experiments of this XQuery cardinality estimation system demonstrate its effectiveness and show high‐accurate estimation results. Utilizing the cardinality estimation properties during the SQL translation of XQuery expression results in an average improvement of 20 percent on the performance of their execution times.

This paper presents a novel framework for estimating the cardinality of XQuery expressions as well as its sub‐expressions. A novel XQuery cardinality estimation benchmark is introduced to establish the basis of comparison between the different estimation approaches in the XQuery domain.

Changes in market and production profiles require a more flexible concept in manufacturing. Computer integrated manufacturing (CIM) describes an integrative concept for joining business and manufacturing islands. In this context, database technology is the key technology for implementing the CIM philosophy. However, CIM applications are more complex and thus more demanding than traditional database applications such as business and administrative applications. Systematically analyses the database requirements for CIM applications including business and manufacturing tasks. Special emphasis is given on integration requirements due to the distributed, partly isolated nature of CIM applications developed over the years. An illustrative sampling of current efforts in the database community to meet the challenge of non‐standard applications such as CIM is presented.

The rapid development of Extensible Markup Language (XML) from a mere data exchange format to a universal syntax for encoding domain specific information increases the need of new query languages specifically visualized to address the characteristics of XML. Such languages should be able not only to extract information from XML documents, but also to apply powerful restructuring operators, based on a well‐defined semantics. Moreover, XML queries should be natural to write and understand, as also end‐users are expected to access the large XML information bases supporting their businesses. The purpose of this paper is to propose a new graphical query language for XML (GQLX) for querying and restructuring XML data.

The methodology emphasizes on GQLX's development, which is based on G‐XML data model syntax to express a wide variety of XML queries, ranging from simple selection to expressive data transformations involving grouping, aggregation and sorting. GQLX has an operational semantics based on the annotated XML, which serves to express queries and data trees in the form of XML. The paper also presents an algorithm to achieve the matching between data and query trees after translating them into annotated XML.

Developed and demonstrated were: a G‐XML syntax; annotated XML for the semantic operations and a matching algorithm.

The future research work on this language lies in expanding it to include recursion and nested queries.

The algorithms/approaches proposed can be implemented to enhance the performance of the XML query language.

The proposed work integrates various novel techniques for XML query syntax/semantic into a single language with a suitable matching algorithm.

This article presents a novel user‐oriented interface for generalised informetric analysis and demonstrates how informetric calculations can easily and declaratively be specified through advanced data modelling techniques. The interface is declarative and at a high level. Therefore it is easy to use, flexible and extensible. It enables end users to perform basic informetric ad hoc calculations easily and often with much less effort than in contemporary online retrieval systems. It also provides several fruitful generalisations of typical informetric measurements like impact factors. These are based on substituting traditional foci of analysis, for instance journals, by other object types, such as authors, organisations or countries. In the interface, bibliographic data are modelled as complex objects (non‐first normal form relations) and terminological and citation networks involving transitive relationships are modelled as binary relations for deductive processing. The interface is flexible, because it makes it easy to switch focus between various object types for informetric calculations, e.g. from authors to institutions. Moreover, it is demonstrated that all informetric data can easily be broken down by criteria that foster advanced analysis, e.g. by years or content‐bearing attributes. Such modelling allows flexible data aggregation along many dimensions. These salient features emerge from the query interface‘s general data restructuring and aggregation capabilities combined with transitive processing capabilities. The features are illustrated by means of sample queries and results in the article.

Extensible Markup Language (XML)‐based data integration systems (DIS) aim to support global updates. Data consistency among data sources is not yet enforced at the integration level or enforced in an ad hoc manner which leads to redundant checking of consistency or unrepairable mistakes. This paper aims to provide XQuery trigger service to enforce data integrity and data consistency in the DIS at the integration level.

Data consistency is enforced among data sources through providing XQuery trigger service for the XML‐DIS. An XQuery trigger model is defined and shown how to use this model to define different integrity constraints and triggers at the integration level. The paper proposes the architecture of the XQuery trigger service and shows how to enforce data consistency in the DIS. Important components including event detection, condition evaluation and action firing are discussed. Necessary algorithms including how to produce ChangeRecord, how to find activated triggers, how to process LET and FOR clauses and how to create data objects from XML fragment are proposed. Trigger termination and failure handling are also discussed.

XQuery trigger can express miscellaneous data integrity constraints and triggers in the DIS and is highly abstract, refined and easy to understand. XQuery trigger service provides an easy‐to‐maintain method of the data consistency rules and a uniform, nonredundant and centralized enforcement of data consistency.

An XQuery trigger model with namespace annotations, which can define constraints and triggers among different data sources. An XQuery trigger service architecture for the XML‐DIS, which can enforce data consistency at the integration level. For DIS administrators, who want to enforce data consistency when permitting updates at the integration level.

Modelling complex knowledge resources can be problematical as there is currently no formalism that can represent the nature of the data‐seeking process at a conceptual level. The purpose of this paper is to develop a knowledge representation formalism, the functional entity relationship diagram (FERD), which comprises a set of extensions to the industry standard entity relationship diagram established by Chen.

The research uses a design science approach to extend the existing ER formalism using the question‐answering (QA) paradigm. It is an extension of standard data modelling theory and is consistent with category theory.

The authors defined the functional entity, an encapsulated data resource that acts as a QA system and enumerated a typology of nine functional entities generated from two established principles to produce a modelling framework that can depict all existentially quantifiable relations, and demonstrated a satisficing extension to that framework (non‐Aristotelian functional entities) for those situations that do not permit such relations. Further, the authors discussed the system of knowledge mixins for qualifying the relations, and presented an adjunct to the framework, cartographic functional entities, to permit formally verifiable documentation.

Future research will address the pragmatic/sociological dimensions of FERD modelling, and test its utility in field case studies.

The FERD conceptualisation incorporates traditional IS modelling as one aspect of a richer modelling system, and thereby includes all of traditional IS repositories as first class, unmediated sources of knowledge. The establishment of standard types of functional entities can provide a framework for the methodical conversion of the declarative design level to the imperative implementation level. It thus has significant practical implications for the management and use of knowledge in organisations.

The research is original and provides a valuable contribution to conceptual modelling and representation of complex knowledge systems.