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Auflistung nach Autor:in "Liddle, Stephen W."

1 - 10 von 40
  • Konferenzbeitrag
    An access control service for dynamic and hierarchical resources: Declarative model and implementation on top of XACML
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Psaila, Giuseppe; Biondi, Fulvio
    The increasing complexity of (distributed) information systems requires new solutions for dealing with access control problems. In particular, information systems are based on a large number of resources, with very complex structure, that must be accessed by a large variety of users. Traditional and instance based solutions are not adequate. In this paper, we propose a new approach to the problem. First of all, we define an access control model which is declarative, modular, hierarchical and instance independent, so that it is suitable for highly dynamic contexts. Then, we reports about the implementation of a Profile Service, which effectively exploits the XACML technology to simplify and shorten the development.
  • Konferenzbeitrag
    Applying web service compositions in systems management
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Karastoyanova, Dimka
    Systems management in any organization depends exclusively on the efforts of a system administrator. Every change in the IT infrastructure landscape requires changes in the systems configuration settings. We propose the use of enterprise registries for addressing the automation of systems configuration. Registries provide global view on the whole IT infrastructure of an enterprise, store a complete configuration data and maintain consistent record of systems state. The role of a registry in the automation of reconfiguration activities in an enterprise can either be passive - with the registry being only a data store for configuration data, or an active one. We view the active approach much more suitable for facilitating automatic system management. Active registries serve not only for data keeping but also command and perform reconfiguration directly onto the enterprise systems. To facilitate the seamless interaction between registry and all systems we propose to extend them with Web service capabilities. To define and perform all the complex sequences of tasks according to the configuration rules defined in a registry we advocate the use of Web Service compositions. We call these process-based Web services “systems management rules”. Furthermore, the development of systems management rules can be automated by using Web Service Flows templates.
  • Konferenzbeitrag
    An approach to advanced data synchronization in complex process control systems
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Kuklenko, D.; Gamzayev, R.; Goloborodko, V.; Tkachuk, M.
    Nowadays for any kind of distributed and multi-level, i.e. complex information systems it is vitally important to represent its data resources in a homogenized form. This paper presents our approach to data synchronization (DS) in complex Process Control Systems (PCS) designed with respect to our real project experience in the domain of PCS for gas-production industry in Ukraine. DS is considered as a stage of more sophisticated approach to data processing called In- telligent Data Engineering (IDE). The IDE framework and some of its modeling aspects are shortly described. The algorithm used at the DS stage for transferring process data between the levels of distributed PCS in XML-format is proposed and implemented. In order to estimate a system performance in a DS publisher node the metrical-based modeling is introduced in our approach.
  • Konferenzbeitrag
    Business rule verbalization
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Halpin, Terry
    Business rules should first be specified at the conceptual level, using concepts and languages easily understood by the business domain experts who are best qualified to validate the rules. This paper focuses on the verbalization of static business rules (i.e. constraints and derivation rules that apply to individual states of the business), ignoring dynamic rules relating to state transitions and/or workflows. We propose desirable language criteria for rule verbalization, and orthogonal dimensions by which rule verbalizations may be classified, and illustrate these general qualities with a wide variety of business rule examples, using model fragments depicted graphically in Entity-Relationship, Object-Role Modeling and Unified Modeling Language notations.
  • Konferenzbeitrag
    Capturing semantics from search phrases: Incremental user personification and ontology-driven query transformation
    (2003) Ermolayev, Vadim; Keberle, Natalya; Plaksin, Sergey; Vladimirov, Vladimir
    Reported is the methodology of the semantic transformation of an initial user's search query in the form of key words or key phrases to the resulting query composed of the relevant concepts of the domain ontology. Transformation methodology is based on incremental user profiling. The mapping of a user's keywords to the concepts of the domain ontology is built according to the presented transformation rules. These rules are based on the usage of the rich set of the semantic relationships comprising subsumption, synonymy, instantiation and meronymy provided as the DAML+OIL ontology. ACM research papers domain is chosen for the methodology evaluation. Transformation algorithm is implemented in the research prototype as the combined capability of the query transformation agent and the ontology agent of the intelligent multi-agent information retrieval mediator1.
  • Konferenzbeitrag
    Cluster analysis in multiset spaces
    (2003) Petrovsky, Alexey B.
    The paper considers techniques for grouping objects that are described with many quantitative and qualitative attributes and may exist in several copies. Such multi-attribute objects may be represented as multisets or sets with repeating elements. Multiset characteristics and operations under an arbitrary number of multisets are determined. The various options for the objects' aggregation (addition, union, intersection) and the main features of hierarchical and non hierarchical cluster analysis in multiset metric spaces are discussed.
  • Konferenzbeitrag
    Combining the best of global-as-view and local-as-view for data integration
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Xu, Li; Embley, David W.
    Currently, there are two main basic approaches to data integration: Globalas-View (GAV) and Local-as-View (LAV). However, both GAV and LAV have their limitations. In a GAV approach, changes in information sources or adding a new information source requires revisions of a global schema and mappings between the global schema and source schemas. In a LAV approach, automating query reformulation has exponential time complexity with respect to query and source schema definitions. To resolve these problems, we offer TIQS as an alternative point of view that is neither GAV nor LAV. The approach uses source-to-target mappings based on a predefined conceptual target schema, which is specified ontologically and independently of any of the sources. The proposed data integration system is easier to maintain than both GAV and LAV, and query reformulation reduces to rule unfolding. Compared with other data integration approaches, our approach combines the advantages of GAV and LAV, mitigates the disadvantages, and provides an alternative for flexible and scalable data integration.
  • Konferenzbeitrag
    A conceptual modeling technique based on semantically complete model, its applications
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Ovchinnikov, Vladimir
    The article proposes a conceptual modeling technique based on Semantically Complete model, the main property of which is that relations carry complete information about interconnection of underlying object types. The paper describes consequences of this property; the most important one is the possibility to use a model relation without its proper name. The author introduces Semantically Complete Query Language, expressions of which is formulated without relation names, describes a closure mechanism allowing to request an interconnection of indirectly related object types by means of a simple enumeration of them. The technique is applied to conceptual modeling of a metallurgical enterprise Manufacturing Execution System as an example. The article proposes use of Semantically Complete model as a unified data access interface to distributed data stored in systems of different architectures and placements, introduces a conception of Semantic Browser based on this interface. The browser permits to view and modify data, has an embedded mechanism of semantic navigation between points of view on information, and a mechanism of creation and publication of new view points by users.
  • Konferenzbeitrag
    A data transformation method based on schema mapping
    (Information systems technology and its applications, 3rd international conference ISTA'2004, 2004) Li, You; Liu, Dongbo; Zhang, Wwiming
    Schema mapping is an important approach to solve the problem of data integration. This paper introduces a research prototype called SDE, which is a system for managing and facilitating the complex tasks of heterogeneous data transformation and integration. We also present a data transformation method based on schema mapping techniques. By analyzing the mappings and schemas it can automatically fulfill the task of data transformation and guarantee that the target result satisfies the target structure and constraints. It allows users to view the other participants' information as an extension of its own information system, without concerning for heterogeneity.
  • Konferenzbeitrag
    Easily accessible GML-based geographic information system for multiple data server over the web
    (2003) Park, Soon-Young; Lee, Jae-Dong; Bae, Hae-Young
    This paper has proposed GML-GIS, which is a prototype system for geographic information service over the Web based on GML (Geography Markup Language). This system generates geographic information into GML document by user requests through URL and provides them with various styles applied to the document on the Web browser. This proposed system converts geographic information of a spatial database into GML documents for interoperability of diverse GIS engine. The architecture of this system is composed of User Interface Module, CGI/Script Module, Application Schema Generator, GML Translator, XML Analyzer, and Documents Pool. By the usage of this system, general users can access easily geographic information of multiple data server with different data type by Web browser