object-oriented database systems (ooDBMSs) are supposed to offer at least the functionality available in commercial relational DBMSs of today. One important consequence of this is that they have to provide a separatio...
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In this paper we describe a fuzzy logic based approach to modelling uncertainty in class hierarchies. It is shown that the traditional view of class hierarchies is subsumed in this model as a special case. The problem...
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In this paper we describe a fuzzy logic based approach to modelling uncertainty in class hierarchies. It is shown that the traditional view of class hierarchies is subsumed in this model as a special case. The problem of multiple inheritance in class hierarchies is discussed and analyzed. The membership value derivations in the inheritance hierarchy reflects the degree of fuzziness existing in the data values and the semantics of the situation being modelled. Thus a more realistic modelling of the universe of discourse is possible through this approach. This model is compatible with existing object-oriented data models.
The authors present a secure kernelized architecture for multilevel object-oriented database management systems. The architecture is based on the notion of a message filter. It builds upon the typical architecture of ...
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Clustering is an effective mechanism for retrieving complex objects. Many object-oriented database management systems have suggested variant clustering schemes to improve their performance. Two issues may compromise t...
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Recently, a new access method, the Hierarchical-Tree (H-tree) was proposed as an efficient access method for object-oriented database that supports superclass-subclass relationship. We show that, the H-tree indexing s...
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Research on IPSE architectures has discussed the benefits of a centralized repository at some length. Such a repository has to not only offer enhanced data management services but also provide for mechanisms to assist...
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Several research prototypes and commercial object-oriented database management systems (DBMSs) that emphasize the representation and manipulation of complex objects are reviewed. It is argued that clustering and buffe...
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Several research prototypes and commercial object-oriented database management systems (DBMSs) that emphasize the representation and manipulation of complex objects are reviewed. It is argued that clustering and buffering schemes tailored to typical complex object operations offer the best near-term means of improving the performance of databases and that research in clustering and buffering should address recent advances in disk technology: optical and parallel disks. The object-oriented DBMSs reviewed are Orion, Iris, GemStone, Encore, Ontos, Versant, and objectStore
This paper presents concurrency control techniques suitable for engineering design environments. Design environments are quite different from conventional business applications for which databases have been traditiona...
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This paper presents concurrency control techniques suitable for engineering design environments. Design environments are quite different from conventional business applications for which databases have been traditionally used. Transactions in a design application are usually very long compared with those in traditional applications, necessitating new concurrency control techniques. We present the Dynamic Validation concurrency control scheme, an optimistic concurrency control scheme that avoids locking data items for extended periods of time. Dynamic validation is designed specifically for low-contention object-oriented database applications with long-duration transactions, such as engineering design applications. We prove that dynamic validation enforces executions that are ''serializable with respect to the database state''. This correctness criterion relaxes the classical serializability criterion, and allows schedules that are equivalent, i.e. produce the same effect, to a serial execution of transactions starting from the same initial database state.
The main problem of today's anaesthesia department is that it spans a multiplicity of locations for data management dealing with data on the pre-OP, intra-OP, and post-OP situation as well as with data obtained fr...
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The main problem of today's anaesthesia department is that it spans a multiplicity of locations for data management dealing with data on the pre-OP, intra-OP, and post-OP situation as well as with data obtained from the laboratories, the administration, etc. In the operating room itself, numerous monitoring devices and anaesthesia machines have to be integrated into the anaesthesia documentation process. Therefore, computerized anaesthesia documentation as a part of quality control urgently needs sufficient support for handling both medical and administrative data, taking into account that the user usually is not a computer expert. We will describe an approach to solve the problem discussed applying object-oriented technology in medical data management, and a sequence of technical realization steps to bring this technology into clinical use.
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