State-based object-oriented programming combines basic advantages of object-oriented and automata-based programming technologies. Its basic features are flexibility, extensibility, and powerful mechanism of descriptio...
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State-based object-oriented programming combines basic advantages of object-oriented and automata-based programming technologies. Its basic features are flexibility, extensibility, and powerful mechanism of description of complex behavior, which is based on finite automata. The disadvantage of the state-based object-oriented programming is the lack of standard methods for designing and implementing state-based classes. In this work, graphical notation for designing state-based classes, which combines capabilities of the class diagrams of the object-oriented programming and behavior diagrams of the automata-based programming, is presented. The proposed graphical notation makes it possible to generalize, decompose, structure, and incrementally extend logic of the state-based classes by means of the inheritance.
A material requirements planning (MRP) system is usually implemented with several constraints, such as replenishment of inventories on a period-by-period bases, which obstruct its dynamic performance. This research pr...
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A material requirements planning (MRP) system is usually implemented with several constraints, such as replenishment of inventories on a period-by-period bases, which obstruct its dynamic performance. This research proposes an active, bucketless, and real-time MRP system. The active MRP system utilizes hybrid architecture that includes an object-oriented database, fuzzy logic controllers, and neural networks. The object-oriented database, which maintains static data relationships, provides superior capabilities in reusability, complex structure operations, and potential integration. The complementary combination of fuzzy logic controllers and neural networks provides a model-free, human-like decision system. Adding triggers and assertions forms an active MRP model.
作者：
Ma, ZhiyiChen, HongjiePeking Univ
Sch Elect Engn & Comp Sci Software Inst Beijing 100871 Peoples R China Peking Univ
Minist Educ Key Lab High Confidence Software Technol Beijing 100871 Peoples R China
Syntactic, semantic and pragmatic defects in object-oriented (OO) models all will result in poor quality of applications based on the models. This study analyses the quality of OO models from two types of novice model...
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Syntactic, semantic and pragmatic defects in object-oriented (OO) models all will result in poor quality of applications based on the models. This study analyses the quality of OO models from two types of novice modellers based on the course projects from the authors 4 years teaching practice. In this study, the authors summarise a set of quality defect types and the typical design activities, quantify the level of occurrence for the defect types and lack of the activities, explore the causes for the defects to occur in OO models in the aspects of syntax, semantics and pragmatics in the phases of OO analysis and design, and conclude preventive measures. These findings can be used for improving the novice modellers' skills for building OO models with good quality.
The main goal of the Alltalk project is to provide transparent database support to the Smalltalk programmer. As a first step towards this goal, the current version of Alltalk extends Smalltalk-80 by providing persiste...
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The main goal of the Alltalk project is to provide transparent database support to the Smalltalk programmer. As a first step towards this goal, the current version of Alltalk extends Smalltalk-80 by providing persistence to Smalltalk objects without adding a database sublanguage, new language syntax, classes or methods. This paper describes the implementation of object management in Alltalk, including database layout, database access methods, in-memory object management and high-level interface from the interpreter. It also discusses how the object manager is integrated in a unique way with the operations of the Alltalk garbage collector and interpreter.
When accessing objects in an object-oriented database, performance can be greatly improved by prefetching objects efficiently. In this paper we present a new object prefetch policy, dynamic selective eager object fetc...
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When accessing objects in an object-oriented database, performance can be greatly improved by prefetching objects efficiently. In this paper we present a new object prefetch policy, dynamic selective eager object fetch (SEOF), which prefetches objects only from selected candidate pages without using any high-level object semantics. Our policy considers both correlations and frequencies of fetching objects when selecting prefetch candidates. Unlike existing prefetch policies, dynamic SEOF utilizes the memory and the swap space of clients efficiently without resource exhaustion. Furthermore, the proposed policy has good adaptability to both the effectiveness of clustering and database size. It also adjusts the degree of prefetching dynamically according to the working environment. We show the performance of the proposed policy through experiments over various multi-client system configurations.
The amount of available data in the neuroscience community is growing rapidly, and is approaching the point where researchers can no longer keep up. This paper describes the development of the Modeler's Workspace,...
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The amount of available data in the neuroscience community is growing rapidly, and is approaching the point where researchers can no longer keep up. This paper describes the development of the Modeler's Workspace, a digital library system we are building to improve the researcher's means of accessing, managing and sharing neuroscience data. The Workspace consists of a distributed system of heterogeneous databases, and a Java front-end for data mining and visualization. A three-tier architecture with CORBA as the middleware facilitates database federation. We discuss our design choices, and some sociological issues, such as how to encourage data submission and ensure security and quality control. (C) 1999 Elsevier Science B.V. All rights reserved.
Deductive databases result from the integration of relational database and logic programming techniques. However, significant problems remain inherent in this simple synthesis from the language point of view. In this ...
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Deductive databases result from the integration of relational database and logic programming techniques. However, significant problems remain inherent in this simple synthesis from the language point of view. In this paper, we discuss these problems from four different aspects: complex values, object orientation, higher-orderness, and updates. In each case, we examine four typical languages that address the corresponding issues.
This paper describes the formalisation of the deductive object-oriented database system ROCK & ROLL, This is a system which integrates the deductive and object-oriented paradigms in a way that is both clean and co...
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This paper describes the formalisation of the deductive object-oriented database system ROCK & ROLL, This is a system which integrates the deductive and object-oriented paradigms in a way that is both clean and consistent, and that has a sound theoretical foundation. The system uses a formally defined object-oriented data model as a foundation for both a logic query language and an imperative data manipulation language in such a way that impedance mismatches are minimised. This paper introduces the facilities offered by ROCK & ROLL, and indicates how their formalisation has been achieved. (C) 1997 Elsevier Science B.V.
Video database applications call for flexible and powerful modeling and querying facilities, which require an integration or interaction between database and knowledge-based technologies. It is also necessary for many...
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Video database applications call for flexible and powerful modeling and querying facilities, which require an integration or interaction between database and knowledge-based technologies. It is also necessary for many real life video database applications to incorporate uncertainty, which naturally occurs due to the complex and subjective semantic content of video data. In this study, firstly, we introduce a fuzzy conceptual data model to represent the semantic content of video data. For that purpose, UML (unified modeling language) is utilized and extended to represent uncertain information along with video specific properties. Secondly, we present an intelligent fuzzy object-oriented database framework for video database applications. The introduced fuzzy conceptual model is used in this framework, which provides modeling of complex and rich semantic content and knowledge of video data including uncertainty. Moreover, it supports various flexible queries including (fuzzy) semantic, temporal and (fuzzy) spatial queries, based on the video data model. We think that the presented conceptual data model and the framework can be used for any video database application. (C) 2009 Elsevier B.V. All rights reserved.
This paper describes practical design and implementation experiences gained when creating Group Support Systems (GSS) in a networked personal computer environment. Examples of GSS based on the shared context model and...
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This paper describes practical design and implementation experiences gained when creating Group Support Systems (GSS) in a networked personal computer environment. Examples of GSS based on the shared context model and implemented using C, C++, and Actor languages are presented. Graphical user interfaces and multitasking extend traditional methods for supporting group work. An object-oriented communication system is introduced comprised of objects that provide support for all inter- and intraprocessor communications between the GSS applications. Multiple levels of data service are provided to maintain shared data, coordinate user views, and transmit cursor positions in a convenient and efficient manner. The applications presented not only demonstrate the viability of implementing GSS on personal computer-based systems, but also show the ability to develop complex applications in different programming environments that make use of common routines. The unique properties of the object-oriented paradigm greatly facilitate the creation and use of Group Support Systems.
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