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object-oriented database schema analysis and inheritance processing: A graph-theoretic approach

DATA & KNOWLEDGE ENGINEERING 1997年第2期24卷 157-181页

作者： Formica, A Groger, HD Missikoff, M CNR IST ANAL SISTEMI & INFORMATI-00185 ROMEITALY SZECHENYI COLL H-9026 GYORHUNGARY

In this paper we address the inheritance process in the context of strongly typed object-oriented database (OODB) systems, allowing multiple inheritance and overriding. For such powerful systems, it is important to analyse the inheritance hierarchy to identify a number of significant properties. The first, schema consistency, is connected to the inheritance conflicts. In the presence of an unsolvable inheritance conflict there is a contradiction in the schema. The second property is related to the termination of the inheritance process. We expect that all the subtypes in the schema, if consistent, can be rewritten in expanded form, after inheritance, in a finite time. Schemas that guarantee these two formal properties will be referred to as correct schemas. In the paper a graph-theoretic method is provided, aimed at supporting the designer in checking the correctness and deriving the expanded form of a schema. Furthermore, from the analysis of the complexity of the inheritance process, a third formal property has been defined, concerning the degree of compactness achievable in a schema, by using inheritance hierarchies. In particular, a class of schemas has been defined, referred to as logarithmic schemas, whose expanded forms, after inheritance, become exponential in the size of the original schemas.

关键词： object-oriented databases multiple inheritance inheritance process inheritance conflicts recursive schemas schema consistency subtyping substitutivity database design

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An ODMG-compatible testbed architecture for scalable management and analysis of physics data

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COMPUTER PHYSICS COMMUNICATIONS 1998年第1-3期110卷 120-124页

作者： Malon, DM May, EN Argonne Natl Lab Argonne IL 60439 USA

This paper describes a testbed architecture for the investigation and development of scalable approaches to the management and analysis of massive amounts of high energy physics data. The architecture has two components: an interface layer that is compliant with a substantial subset of the ODMG-93 Version 1.2 specification, and a lightweight object persistence manager that provides flexible storage and retrieval services on a variety of single- and multi-level storage architectures, and on a range of parallel and distributed computing platforms. Published by Elsevier Science B.V.

关键词： object-oriented databases object persistence multilevel storage management ODMG

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User-oriented views in health care information systems

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IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING 2002年第12期49卷 1387-1398页

作者： Portoni, L Combi, C Pinciroli, F Politecn Milan Dipartimento Bioingn I-20133 Milan Italy CNR Ctr Ingn Biomed I-20133 Milan Italy

In this paper, we present the methodology we adopted in designing and developing an object-oriented database system for the management of medical records. The designed system provides technical solutions to important requirements of most clinical information systems, such as 1) the support of tools to create and manage views on data and view schemas, offering to different users specific perspectives on data tailored to their needs;2) the capability to handle in a suitable way the temporal aspects related to clinical information, and 3) the effective integration of multimedia data. Remote data access for authorized users is also considered. As clinical application, we describe here the prototype of a user-oriented clinical information system for the archiving and the management of multimedia and temporally oriented clinical data related to percutaneous transluminal coronary angioplasty (PTCA) patients. Suitable view schemas for various user roles (cath-lab physician, ward nurse, general practitioner) have been modeled and implemented on the basis of a detailed analysis of the considered clinical environment, carried out by an object-oriented approach.

关键词： cardiology data clinical information systems object-oriented databases object-oriented views temporal databases WWW-based information access

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An object-oriented database design for improved performance

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DATA & KNOWLEDGE ENGINEERING 2001年第2期37卷 117-138页

作者： Gorla, N Wayne State Univ Informat Syst & Mfg Dept Detroit MI 48202 USA

object-oriented databases (OODBs) are known to be rich in functionality but poor in performance. One of the important factors that affect performance is the physical database design. We developed a methodology for the design of an efficient storage structure of OODB that minimizes the database operating costs. The input for our method is the logical OODB schema and set of user transactions of retrieval and update types. The output of our method is the determination of which instance variables should be inherited from direct and indirect superclasses and stored in which subclasses. We used a genetic algorithm (GA) to solve this intractable problem. The methodology was applied on a university database. Compared to previous storage models, the storage model produced with our methodology showed database performance improvement ranging from 26% to 31%, on the average. Our results demonstrate a cost-effective storage structure design that boosts the operating performance of OODBs. (C) 2001 Published by Elsevier Science B.V.

关键词： object-oriented databases database operating cost performance evaluation physical database design genetic algorithms optimization

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ACQUIRING EXPERIENCES WITH THE MODELING AND IMPLEMENTATION OF THE PROJECT LIFE-CYCLE PROCESS - THE PMDB WORK

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SOFTWARE ENGINEERING JOURNAL 1991年第5期6卷 259-274页

作者： PENEDO, MH SHU, C TRW CO INC REDONDO BEACHCA 90278

Formalising and automating the software life-cycle processes are key factors in the improvement of software productivity. This paper describes the Project Master Database (PMDB) work, three generations of investigations into the modelling and encoding of software life-cycle processes;it briefly describes past activities and concentrates on more recent investigations. It presents an approach to software process modelling based on an object-based model called the PMDB + model, which includes project elements, relationships between those elements and behavioural descriptions of project life-cycle activities. An overview of the model is presented, together with examples to illustrate the application of the model to existing software processes. It also describes a prototyping exercise that implemented the PMDB + model in an object-oriented database management system. Key results of these investigations, the impact of process implementations on the architecture of environments, and lessons learnt from the exercises are described.

关键词： project elements prototyping exercise software engineering object-oriented database management system encoding software process modelling Software engineering techniques project life-cycle activities Project Master Database object-oriented databases PMDB+model object-oriented programming software life-cycle processes process implementations object-oriented databases object-oriented programming behavioural descriptions object-based model

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Computational music representation based on the generative theory of tonal music and the deductive object-oriented database

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COMPUTER MUSIC JOURNAL 2003年第3期27卷 73-89页

作者： Hirata, K Aoyagi, T NTT Commun Sci Labs Kyoto 6190237 Japan Tsuda Coll Kodaira Tokyo 1878577 Japan

Describes a framework of music presentation. Definition of homophony and polyphony; Discussion on the generative theory of tonal music and the deductive object-oriented database; Representation of polyphony; Primitives.

关键词： Music object-oriented databases object-oriented methods (Computer science) databases

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A temporal versioned object-oriented data schema model

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COMPUTERS & MATHEMATICS WITH APPLICATIONS 2001年第1-2期41卷 177-192页

作者： Rodríguez, L Ogata, H Yano, Y Univ Tokushima Fac Engn Dept Informat Sci & Intelligent Syst Tokushima 770 Japan

This paper describes in a formal way a data schema model which introduces temporal and versioning schema features in an object-oriented environment, In our model, the schema is time dependent and the history of the changes which occur on its elements are kept into version hierarchies. A fundamental assumption behind our approach is that a new schema specification should not define a new database, so that previous schema definitions are considered as alternative design specifications, and consequently, existing data can be accessed in a consistent way using any of the defined schemas. (C) 2001 Elsevier Science Ltd. All rights reserved.

关键词： object-oriented databases temporal databases schema versioning

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Automatic object-oriented coding facility for product life cycle management of discrete products

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INTERNATIONAL JOURNAL OF COMPUTER INTEGRATED MANUFACTURING 2014年第1期27卷 60-84页

作者： Khan, Wasim A. Hussain, Amir GIK Inst Engn Sci & Technol Topi 23640 Swabi Pakistan Inst Business Adm Karachi 74400 Pakistan

Discrete products are produced in enormous quantity and diversity all over the world. A global collaborative manufacturing environment requires the minimisation of environmental impact that these products shall ultimately pose. The implementation of an efficient product life cycle management system that encapsulates complete historical information about the product shall prove useful. This information may pertain to the design methodology, material type, details regarding manufacturing methods, use of coating or paints and exposure to radiation, chemicals of varying pH and electroweak forces during production or use. It is essential to have access to this information when the product is in use or in the disassembly stage at the end of the useful life of a product to accomplish the proper reuse or disposal of each component. A coding system that embodies the product life cycle stages for discrete products is envisaged. The proposed coding system stores parameters that are related to the design, manufacture, usage and disposal of a product. A computer programme is developed to establish a product life cycle code (PLCC) in the form of a 256-bit binary number or 64-bit hexadecimal number. The code can be allocated to a component or product at its inception in an interactive web session and stored in a repository for record keeping. The cradle-to-grave binary or hexadecimal code becomes an essential part of each component and product and facilitates the usage, disassembly and disposal of each component. A case study related to the generation of PLCC for discrete products is included towards the end of the article.

关键词： product life cycle code coding and classification system design discrete manufacturing object-oriented programming object-oriented databases

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Towards concept-oriented databases

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DATA & KNOWLEDGE ENGINEERING 1999年第1期30卷 23-55页

作者： Dubitzky, W Büchner, AG Hughes, JG Bell, DA Univ Ulster Fac Informat Newtonabbey BT37 0QB Antrim North Ireland

Case-based reasoning (CBR) systems define knowledge in terms of a memory or library of past cases and a retrieval mechanism that revolves around retrieving data relevant to a goal query. Additionally, such systems employ an adaptation component that transforms the retrieved data into a solution to the problem expressed by the original query. The combination of goal query and the subsequent solution transformation is referred to as CBR goal query. Goal queries are concerned with data that is close to the request expressed in the query. Conventional relational and object-oriented databases are usually concerned specific queries. Extending conventional object-oriented data models,:this paper proposes a concept-oriented data model that provides a variety of mechanisms to support conventional goal and CBR goal queries. It is shown that such a concept-oriented data model could be used as the core for a more general knowledge base management system. (C) 1999 Elsevier Science B.V. All rights reserved.

关键词： data model object-oriented databases case-based reasoning knowledge representation reasoning under uncertainty

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QUERY BY CLASS, RULE, AND CONCEPT

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APPLIED INTELLIGENCE 1994年第2期4卷 133-156页

作者： STAUDT, M NISSEN, HW JEUSFELD, MA 1. Informatik V RWTH Aachen Ahornstr. 55 52056 Aachen Germany

The ideal query language for a knowledge base will probably never be found: easy formulation and easy evaluation of queries are two conflicting goals. Easy formulation asks for a flexible, expressive language near to human language or gestures. Easy evaluation of queries requires an effective mapping to machine code, which computes the correct answer in a finite number of steps. This article approaches the problem by a query language with three faces. The first projects queries to concepts of the knowledge representation language KL-One for easy formulation and readability. The second presents queries as rules of a deductive database with fixpoint semantics. The third presents queries as classes whose instances are the materialized answer (view) to the query. The methods for maintaining and updating the views are compiled from their deductive interpretation.

关键词： QUERY LANGUAGES object-oriented databases DEDUCTIVE databases VIEW MAINTENANCE INTENTIONAL UPDATES SUBSUMPTION

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