The focus of this article is the transformation of conceptual data models (such as ER, NIAM and PSM) to object-oriented databases. This transformation is captured within the framework of a two-level architecture. Conc...
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The focus of this article is the transformation of conceptual data models (such as ER, NIAM and PSM) to object-oriented databases. This transformation is captured within the framework of a two-level architecture. Conceptual models are first mapped to abstract intermediate specifications, which are then transformed to database schemas in a given object-oriented database environment. This enables us to treat different target systems in a uniform way. As final implementation environments, we consider object-oriented as well as object-relational DBMSs, including the SQL3 and ODMG-93 standards. We do not reveal the specific details of these standards. Rather, we use intermediate representations expressed in F-logic, a logic-based abstract specification language for object-orientedsystems. Several transformation alternatives are discussed in a formal context, resulting in a collection of design options. (C) 1998 Elsevier Science B.V.
Atomic transactions are now a familiar paradigm for distributed programming and have been provided in a number of object-oriented languages. Much effort has also been expended on developing open transaction processing...
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Atomic transactions are now a familiar paradigm for distributed programming and have been provided in a number of object-oriented languages. Much effort has also been expended on developing open transaction processing systems which support distributed transactions involving multi-vendor database systems. This paper addresses a number of issues that arise in combining object-oriented distributed programming with open transaction processing. We describe an approach to supporting transactions which can access objects and other resource types, such as files and records, consistently, and which is independent of the use of any particular object-oriented programming language. We discuss both the design of a generic run-time interface which provides language independent support for atomic objects and transactions and, following the X/Open model for open transaction processing, the design of an interface between the transaction manager and a resource manager which is suitable for the requirements of object-orientedsystems. We illustrate our approach by describing the transaction sub-system of the Amadeus/RelaX implementation of the Comandos platform which supports a number of popular object-oriented languages and has been integrated with an existing relational database system.
This paper reports and evaluates the experience of applying object-oriented techniques to the development of a real-time system for monitoring and control of remote sites. The system, which is currently installed at s...
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This paper reports and evaluates the experience of applying object-oriented techniques to the development of a real-time system for monitoring and control of remote sites. The system, which is currently installed at several sites in the UK and elsewhere in Europe, also includes database management functions and an interactive operator interface. It was originally designed in 1987 and has evolved in an incremental fashion to the present day. The paper focuses on the object-oriented aspects of the system architecture and on the development process model. Together they provide a technical and organisational framework for projects of similar nature. The pros and cons of the solutions adopted are discussed.
Embedded computer systems, incorporated in various types of products, are common in many everyday goods, industrial equipment and machine automation systems. Because embedded systems have been developed for several ye...
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Embedded computer systems, incorporated in various types of products, are common in many everyday goods, industrial equipment and machine automation systems. Because embedded systems have been developed for several years in the context of certain product domains, but for different customers and based on different technologies, families of embedded systems have emerged in those product domains. Such families need to be constantly re-engineered for developing new systems. Yet, organised reuse of the experiences gained from the development of certain system families is not widespread. In connection with the increased use of object-oriented methodologies in the development of real-time computer systems, better means will be provided for reusable embedded software architectures and components. As a result of the developments in the 1980s, re-engineering for reusability requires in practice the redesign and generalisation of individual structured embedded system models and software implementations as object-oriented models and implementations. However, there is a gap between the results of research on pure object-oriented approaches and their implementation for production use in a re-engineering process of embedded software. A pure object-oriented approach would result in the losing of the straightforward traceability between the re-engineered analysis and design models and the original structured models. Combinative and adaptive object-oriented approaches seem to be reasonable for the re-engineering process, because they incorporate and modify traditional static, dynamic and functional modelling techniques into object-oriented modelling. The reasons for this opinion are justified in this paper using the remodelling of control software of machine automation systems as an example.
The Network-on-Chip (NoC paradigm brings networks inside chips. We use the routing capabilities inside NoC to serve as a replacement for Virtual Method Table (VMT) for object-oriented (OO) designed hardware/software c...
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The Network-on-Chip (NoC paradigm brings networks inside chips. We use the routing capabilities inside NoC to serve as a replacement for Virtual Method Table (VMT) for object-oriented (OO) designed hardware/software co-designsystems where some methods could be implemented as hardware modules. This eliminates VMT area and performance overhead in OO co-designed embedded systems where resources are limited and where some functionality needs to be implemented in hardware to meet performance goals of the system. Our experimental results on real world embedded applications show up to 32.15% lower area and up to 5.1% higher speed compared to traditional implementation using VMT. (C) 2007 Elsevier Inc. All rights reserved.
It is widely accepted that more widespread use of object-oriented techniques can only come about when there are techniques and tool systems that provide design support beyond visualizing code. Distinct software metric...
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It is widely accepted that more widespread use of object-oriented techniques can only come about when there are techniques and tool systems that provide design support beyond visualizing code. Distinct software metrics are considered as being able to support the design by indicating critical components with respect to various quality factors such as maintainability and reliability. Unfortunately, many object-oriented metrics were defined and applied to classroom projects, but no evidence was given that the metrics are useful and applicable-both from an experience viewpoint and from a tools viewpoint-for industrial object-oriented development. Distinct complexity metrics have been developed and integrated in a Smalltalk development support system called SmallMetric. Thus we achieved a basis for software analysis (metrics) and development support (critique) of Smalltalk systems. The main concepts of the environment including the underlying metrics are explained, its use and operation are discussed and some results of the implementation and its application to several industrial projects are given with examples. Copyright (C) 1999 John Wiley & Sons, Ltd.
This paper presents an aided design methodology of flexible manufacturing system control with a view to industrial implementation. The approach considered through a modelling phase, the a validation phase by simulatio...
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This paper presents an aided design methodology of flexible manufacturing system control with a view to industrial implementation. The approach considered through a modelling phase, the a validation phase by simulation and finally a distributed implementation phase. In the modelling phase, based on the Petri net formalism, we demonstrate the hierarchical aspect which separates the part now control and the product resource control. Tn addition, we emphasize generic aspects which allow us to use an object-oriented approach. These aspects and the set of modelled objects are directly used in the simulation and production phases after an automatic translation in an implementation language (ADA in our case). In consequence, the distributed location for those two phases is well facilitated from the viewpoint of the approach used.
A pattern for information system implementation is proposed. The pattern is based on the commonly accepted object-oriented methodologies of design and development oriented toward widely used imperative programming lan...
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A pattern for information system implementation is proposed. The pattern is based on the commonly accepted object-oriented methodologies of design and development oriented toward widely used imperative programming languages. At the same time, this pattern makes it possible to fully use the power of declarative possibilities of the DBMS query language. The presented estimations demonstrate much higher performance of the applications obtained compared to those created by means of commonly accepted techniques.
The Department of Electrical Engineering at the University of Brighton has been directing research at improving manufacturing flexibility within the electronics industry, particularly within surface mount technology (...
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The Department of Electrical Engineering at the University of Brighton has been directing research at improving manufacturing flexibility within the electronics industry, particularly within surface mount technology (SMT) production. All possible tasks within the SMT manufacturing cycle were identified and documented, to provide a basis on which to apply the techniques of an object-orienteddesign methodology. During the design on the vision framework, classes were immediately implemented and evaluated using a software application generation environment called KAPPA. This environment allows classes to be constructed graphically, and is supported by its own 4GL programming language.
The central concept of the work described in this paper is that a database can be created which contains all the information about a complex engineering system specifically a Building Management System (BMS). This dat...
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The central concept of the work described in this paper is that a database can be created which contains all the information about a complex engineering system specifically a Building Management System (BMS). This database will be updated and modified throughout the system lifecycle. Due to the large amount of information required to be entered into these databases all data entry is done through graphical interfaces according to the maxim 'A picture is worth ten thousand words'. The user draws a picture of what is required, and this is then compiled into the desired database form.
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