In this paper we present an approach of image retrieval by Content in an objectoriented database. The content of image includes automatically extracted features such as colors, textures, and manually extracted featur...
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ISBN:
(纸本)0818677287
In this paper we present an approach of image retrieval by Content in an objectoriented database. The content of image includes automatically extracted features such as colors, textures, and manually extracted features such as relevant regions, shapes, key words and texts. All these features and their behaviors are represented in an object-oriented database. Finally a KD-tree is used to model the index of features, and to support efficiently the match engine.
Integrity constraints are general properties that a given database is expected to satisfy. Integrity constraints can be implicit in the schema of the database or explicitly expressed as, for instance, logical formulae...
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Current objectoriented (OO) Database schema structures allow isa relationships and multiple inheritance. We extend these structures with features from semantic modelling that are not traditionally supported by OO sch...
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ISBN:
(纸本)9783540617846
Current objectoriented (OO) Database schema structures allow isa relationships and multiple inheritance. We extend these structures with features from semantic modelling that are not traditionally supported by OO schemas: disjointness of classes and class intersection inclusion into other classes as well as negations of these statements. Formally we represent schemas as sets of first order monadic formulas. We provide a formal system for schemas that is sound and complete both for finite and unrestricted implications. Based on it and on well known algorithms we show that checking formula deduction is polynomial. Consistency is characterized completely in two alternative ways in terms of formula deduction. We show that these results allow us to deal efficiently with the issues of incremental/ intelligent consistency checking, redundancy removal, minimal representation and updating in OO schemas.
object-oriented Database Management Systems (OODBMS) are becoming popular and are being used in a large number of application domains, many of which are inherently distributed. Optimal application performance of a dis...
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Constraint technology can be used to extend the functionality and performance of current database systems in a variety of ways. In this paper, we show how to use constraints for the processing of queries that contain ...
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It is widely acknowledged that clustering is a cornerstone for the performance of database management systems. In particular, object-oriented databases have properties which may compromise the effectiveness of a clust...
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ISBN:
(纸本)9783540616566
It is widely acknowledged that clustering is a cornerstone for the performance of database management systems. In particular, object-oriented databases have properties which may compromise the effectiveness of a clustered structure, i.e., object updates and multiple relationships. The clustering problem consists in finding a partition of the set of the objects in the database. Our approach is similar to the one adopted in Schkolnick [1] for the hierarchical model. When objects are grouped together, it is desirable that these objects be accessed together in the future. We have an operational approach: we will evaluate the benefits of our clustering strategy and show how to dynamically adapt it.
In this paper, we present the implementation of a compact temporal object model based on time sequences as a general purpose collection class, called the Chronic le, in the Smalltalk/DB language. This provides an obje...
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In this paper we present the graphical user interface of Mosaico, an environment for the analysis and conceptual modeling of object-oriented database applications. Mosaico is based on a formalism, the object-oriented ...
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object-orientation as the catch phrase of the 90ies in computer science is said to model reality in a better way. To find out if this is true, a company which produces photographic base paper initiated a study. The fo...
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ISBN:
(纸本)9783540616566
object-orientation as the catch phrase of the 90ies in computer science is said to model reality in a better way. To find out if this is true, a company which produces photographic base paper initiated a study. The following article summarises the proceeding during the analysis, design, and implementation, and presents the results and experiences gathered during coupling object-oriented modeling and relational databases.
Our work is motivated by the desire to develop methods to comprehend large vocabularies and large schemas of object-oriented databases. The ability of a user of a database participating in a federated system to retrie...
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