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Message oriented middleware (MOM) services, based on the concept of persistent queues, are widely used for reliable asynchronous communication to deal with the disadvantages of the closely coupled communication model. This paper introduces some new functionality for queuing services (QS) in order to make them more powerful for the need of modern application programs and presents JPMQ, a sample implementation...
In this paper we address aspects of traceability in Information Systems design, particularly with those methodologies utilizing rich, and possibly multiple (behavioural) models. We consider this issue within the broader context of IS development, and focus on the potential for communication among human actors. Specifically, we consider the question of repository design for supporting design activities...
A commonly followed approach in database design is to collect user views on the database and to develop the conceptual schema of the database by integrating these views. The design of object-oriented databases involves the design of object behavior next to the design of object structure. Object-oriented design notations usually represent object behavior at two levels of detail: by activities...
Mining for association rules between items in a large database of sales transactions is an important database mining problem. However, the algorithms previously reported in the literature apply only to static databases. That is, when more transactions are added, the mining process must start all over again, without taking advantage of the previous execution and results of the mining algorithm. In...
Building an index tree is a common approach to speed up the k nearest neighbour search in large databases of many-dimensional records. Many applications require varying distance metrics by putting a weight on different dimensions. The main problem with k nearest neighbour searches using weighted euclidean metrics in a high dimensional space is whether the searches can be done efficiently. We present...
Content-based image retrieval systems rely on a query-by-example technique often using a limited set of global image features. This leads to a rather coarse-grain approach to locate images. The next step is to concentrate on queries over spatial relations amongst objects within the images. This calls for a small collection of image retrieval primitives to form the basis of an image retrieval system...
Multimedia databases include many types of new data. One common property of these data items is that they are very large. We exploit the concept of transformational representations to logically store images without the bitmap. This technique is similax to views in traditional database systems. The technique is useful when users axe editing images in the database to create new images. Our method produces...
In this paper the establishment of a supporting knowledge base for a looselycoupled federation of heterogeneous databases available over a computer network is described. In such a federation, user information requirements are not static. The changes and evolution in user information needs reflect both the changing information available in the federation as databases join and leave it and their contents...
Correct transformations and integrations of schemata within the process of federated database design have to encompass existing local integrity constraints. Most of the proposed methods for schema transformation and integration do not sufficiently consider explicit integrity constraints. In this paper we present an approach to deal with integrity constraints. Our approach bases on the idea to relate...
We describe in brief a lazy functional database language Relief, which supports an entity-function model and provides for update and the input of data by means of functions with side-effects. An eager let construct is used within the lazy graph reduction mechanism to sequence the effects. To redress the loss of referential transparency we have implemented an effects checker which can identify referentially...
Deductive database languages have often evolved with little regard for ongoing developments in other parts of the database community. This tendency has also been prevalent in deductive object-oriented database (DOOD) research, where it is often difficult to relate proposals to the emerging standards for object-oriented or object-relational databases. This paper seeks to buck the trend by indicating...
The chase of datalog programs is anew way to reason about datalog programs that are evaluated on databases consistent with a set of constraints. It is an equivalence-preserving program transformation that uncovers properties of datalog programs that must hold when they are evaluated on consistent databases. Here, we summarizes our research.
We describe the TENTACLE system, an extensible database system which uses a graph data model to store and manipulate poorly structured data. To enable the database to be tailored to particular problem domains, it has been equipped with a small embedded interpreter which can be used to construct the equivalent of customised views of or front-ends to a given semi-structured data domain. To demonstrate...
The advent of the World Wide Web (WWW) has meant there is a growing need to link information held in databases and files with information held in other types of structure [2]. This poster presents a toolkit which enables information held in tables within documents to be linked with data held in conventional databases. The toolkit addresses the problems of:- • extracting tabular data from various...
Current database management system technology is unable to provide adequate support for Nomadic Computing. Mobile applications require systems which are sufficiently lightweight and customisable to provide high performance while consuming minimal power, yet extensible enough to adapt to a constantly changing environment. Current DBMS architectures do not provide this level of customization or adaptability...
The ITSE system (Integrated Translation Support Environment) is a toolkit whose architecture is aimed at enabling the exchange of data between different database interoperation tools as well as the dynamic addition of new tools. Each of the tools addresses a specific set of interoperation problems and achieves interoperation using an intermediate semantic representation to map from source to target...
Constraints are commonly used to maintain data integrity and consistency in databases. This ability to store constraint knowledge, however, can also be viewed as an attachment of instructions on how a data object should be used. In other words, data objects are annotated with declarative knowledge which can be transformed and processed. This abstract describes our work in Aberdeen on the fusion...
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