16,315 research outputs found

    Semantic Constraint Modeling in Database Using the Applicative Data Language.

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    There is a growing need to incorporate database integrity subsystems into large information systems in engineering design environments and real-time control and monitoring environments. The objectives of the integrity subsystem are to provide a user interface for constraint specification, to compile the specification into enforcement strategies, and to check data integrity at both compile-time and run-time. The approach proposed by this research is to develop the conceptual view of the database using the Entity Relationship Model (ERM). Users\u27 queries and semantic constraints can be specified by an ER-based data language, the Applicative Data Language (ADL). Any ADL constraint specification is compiled into both a compile-time and a run-time checking strategy for enforcement. The integrity subsystem, then, automatically maintains the consistency of data whenever there is a change in the database state. The basic constructs of ADL are data structures, functions, and predicates. It takes advantage of the semantic clarification of objects and relationships in the Entity Relationship Model by doing, first, an object level computation and, then, a data element level computation. The object level computation determines how objects are associated with each other. The data element computation, on the other hand, examines the data values of those associated objects and derives new relations from these values. A semantic constraint, therefore, is formulated as a computation procedure that maps the current database state to a TRUE or FALSE value. The computational syntax of ADL allows us to compile directly each constraint specification into a transition digraph for compile-time constraint checking. This research proposes the incremental computation strategy for efficient run-time constraint checking. The objective of the strategy is to do run-time constraint checking without full evaluation of the database. The entire computation procedure centers around the user\u27s update. It propagates the incremental changes along the transition digraph to infer the effect of the update upon the new truth value of the semantic constraint. This research concludes that ADL with its generality in semantic constraint modeling and its enforcement strategies at both compile-time and run-time is adequate as the architecture for an integrity subsystem supporting an Entity Relationship database

    Open issues in semantic query optimization in relational DBMS

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    After two decades of research into Semantic Query Optimization (SQO) there is clear agreement as to the efficacy of SQO. However, although there are some experimental implementations there are still no commercial implementations. We first present a thorough analysis of research into SQO. We identify three problems which inhibit the effective use of SQO in Relational Database Management Systems(RDBMS). We then propose solutions to these problems and describe first steps towards the implementation of an effective semantic query optimizer for relational databases

    Knowledge Representation Concepts for Automated SLA Management

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    Outsourcing of complex IT infrastructure to IT service providers has increased substantially during the past years. IT service providers must be able to fulfil their service-quality commitments based upon predefined Service Level Agreements (SLAs) with the service customer. They need to manage, execute and maintain thousands of SLAs for different customers and different types of services, which needs new levels of flexibility and automation not available with the current technology. The complexity of contractual logic in SLAs requires new forms of knowledge representation to automatically draw inferences and execute contractual agreements. A logic-based approach provides several advantages including automated rule chaining allowing for compact knowledge representation as well as flexibility to adapt to rapidly changing business requirements. We suggest adequate logical formalisms for representation and enforcement of SLA rules and describe a proof-of-concept implementation. The article describes selected formalisms of the ContractLog KR and their adequacy for automated SLA management and presents results of experiments to demonstrate flexibility and scalability of the approach.Comment: Paschke, A. and Bichler, M.: Knowledge Representation Concepts for Automated SLA Management, Int. Journal of Decision Support Systems (DSS), submitted 19th March 200

    Interoperability, Trust Based Information Sharing Protocol and Security: Digital Government Key Issues

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    Improved interoperability between public and private organizations is of key significance to make digital government newest triumphant. Digital Government interoperability, information sharing protocol and security are measured the key issue for achieving a refined stage of digital government. Flawless interoperability is essential to share the information between diverse and merely dispersed organisations in several network environments by using computer based tools. Digital government must ensure security for its information systems, including computers and networks for providing better service to the citizens. Governments around the world are increasingly revolving to information sharing and integration for solving problems in programs and policy areas. Evils of global worry such as syndrome discovery and manage, terror campaign, immigration and border control, prohibited drug trafficking, and more demand information sharing, harmonization and cooperation amid government agencies within a country and across national borders. A number of daunting challenges survive to the progress of an efficient information sharing protocol. A secure and trusted information-sharing protocol is required to enable users to interact and share information easily and perfectly across many diverse networks and databases globally.Comment: 20 page

    Penghasilan dan penilaian video pembelajaran (CD) bagi mata pelajaran Prinsip Ekonomi (BPA 1013) bertajuk permintaan dan penawaran di KUITTHO

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    Kajian ini dijaiankan untuk meniiai keberkesanan sebuah video pembeiajaran (CD) mata peiajaran Prinsip Ekonomi (BPA 1013) bertajuk Permintaan dan Penawaran. Bagi tujuan tersebut, sebuah video pembelajaran telah dihasilkan membantu pelajar bagi memahami mata pelajaran berkenan semasa proses pengajaran dan pembelajaran berlaku. Video pembelajaran yang dihasilkan ini kemudian dinilai dari aspek proses pengajaran dan pembelajaran, minat dan persepsi responden terhadap ciri-ciri video (audio dan visual). Seramai 60 orang pelajar semester 2 Sarjana Muda Sains Pengurusan di Kolej Universiti Teknologi Tun Hussein Onn telah dipiih bagi membuat penilaian kebolehgunaan produk ini sebagai alat bantuan mengajar di dalam kelas. Semua data yang diperolehi kemudiannya dikumpulkan bagi dianalisis dengan menggunakan perisian "SrarMfKM/ Pac/rageybr Rocaj/ Sb/'eace " (SPSS). Hasil dapatan kajian yang dilakukan jelas menunjukkan video pengajaran yang dihasilkan dan dinilai ini amat sesuai digunakan bagi tujuan memenuhi keperluan proses pengajaran dan pembelajaran subjek ini di dalam kelas
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