The Dynamic Brain Project will create an interactive database on the human brain, available via the Internet. In addition to medical images and textual information, the completed project will give users access to all ...
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In this paper, the performance issues of objects with roles are addressed. In our previous paper, Double Signature Indexing Scheme (DSIS) was proposed for a dynamic object-oriented database programming language with r...
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The representation scheme for models is a key issue in decision support system(DSS). First,various representation scheme for models is outlined. Second, a new method of representation for models, which is based on aut...
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ISBN:
(纸本)0780342534
The representation scheme for models is a key issue in decision support system(DSS). First,various representation scheme for models is outlined. Second, a new method of representation for models, which is based on automata, is presented. Third, a object-oriented model management system has been realized.
The integration of the non-traditional database systems, such as object-oriented database, multimedia database and file system, makes the information integration technique face with the new challenge. This paper propo...
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ISBN:
(纸本)0780342534
The integration of the non-traditional database systems, such as object-oriented database, multimedia database and file system, makes the information integration technique face with the new challenge. This paper proposes an object-wrapping technique to the development of integrated system. This object-wrapping technique efficiently makes use of the object-oriented technology to support the schema integration mechanism, in particular to be capable of integrating the file system in which the schema doesn't exist. The feasibility of this technique is demonstrated by the development of the prototype system CIM-IDS. This paper will introduce the object-wrapping technique in CIM-IDS and the design of its core part-object wrapper in detail.
The integration of object-oriented programming concepts with databases is one of the most significant advances in the evolution of database systems. Many aspects of such a combination have been studied, but there are ...
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The integration of object-oriented programming concepts with databases is one of the most significant advances in the evolution of database systems. Many aspects of such a combination have been studied, but there are few models to provide security for this richly structured information. We develop here an authorization model for object-oriented databases. This model consists of a set of policies, a structure for authorization rules, and algorithms to evaluate access requests against the authorization rules. User access policies are based on the concept of inherited authorization applied along the class structure hierarchy. We propose also a set of administrative policies that allow the control of user access and its decentralization. Finally, we study the effect of class structuring changes on authorization.
This article presents a framework developed for accommodating various object migrations in 'statically-typed' objectdatabases. Requirements for supporting object migrations are stipulated, and a conceptual mo...
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This article presents a framework developed for accommodating various object migrations in 'statically-typed' objectdatabases. Requirements for supporting object migrations are stipulated, and a conceptual model for describing and facilitating different kinds of migrations is described. Associated issues of controlling such migrations are then addressed, along with an initial investigation on the inference of implied migration paths and the completeness of migration operators. Some guidelines are then given to help users conduct migrations more effectively. An implementation prototype on top of an object-oriented database system was built, which embodies full support of all migration types specified in the migration model.
This paper deals with modelling constraints in object-oriented databases, with emphasis given on exceptions. Constraints are restrictions on properties and relations of database objects that ensure the integrity of da...
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ISBN:
(纸本)3540587861
This paper deals with modelling constraints in object-oriented databases, with emphasis given on exceptions. Constraints are restrictions on properties and relations of database objects that ensure the integrity of data. Therefore, they should be obeyed by every object, but as in real-life, there are some exceptions to this ruler object-oriented databases provide rich semantic constructs, adequate to model real-world relations. Inheritance of constraints in object-oriented databases has been treated in a completely mandatory way, providing no room for exceptions. In this paper, an object-oriented constraint representation scheme is presented, along with a methodology for modelling constraint exceptions. Finally, an algorithm is described that ensures correct runtime resolution of constraint applicability. Since business is not in abstract, but in real-world, business database modelling would be greatly benefited from a tool that allows both a clear definition and an efficient enforcement of constraints with exceptions.
Much of the work in query optimization in object-oriented database is devoted to finding efficient ways of path traversais expressed in a query. In the environment where a query involves classes distributed across sev...
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We investigate three logic paradigms of increasing level of expressivity in modeling strongly typed, polymorphic, object-oriented database systems and their applications. The first paradigm is based on Horn clauses wi...
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This paper proposes a simple and powerful approach to associating rules with events in reactive object-oriented database systems. In it we propose a new run time subscription mechanism, which associates rules with spe...
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