Concerns the modelling of complex hierarchical manufacturing systems, where overall control of the manufacturing organisation is devolved through manufacturing cells and ultimately to individual operations. Control is...
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Concerns the modelling of complex hierarchical manufacturing systems, where overall control of the manufacturing organisation is devolved through manufacturing cells and ultimately to individual operations. Control is maintained at the many levels by the flow of instructions from higher levels, but it is essential to the coordination of lower level activities that actual performance results in revised control through some form of feedback loop. The background of simulation is outlined in relationship to object-orientedprogramming, and then the proprietary software used is considered. Three strands of related research undertaken to date are described, then it is shown how these strands may be drawn together to form an integrated manufacturing system modelling package.< >
Summary form only given, as follows. The object Management Group is a not-for-profit umbrella organisation set up in 1989 to promote industry standards for application integration via object technology. OMG does not i...
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Summary form only given, as follows. The object Management Group is a not-for-profit umbrella organisation set up in 1989 to promote industry standards for application integration via object technology. OMG does not itself produce specifications or software; instead it populates its architectural framework (the object management architecture) with interface specifications solicited from its member organisations. The central plank of this architecture is the object request broker, the mechanism which seamlessly transmits requests and responses between objects in a distributed heterogenous computing environment.< >
Concerned with the use of object-oriented systems in the simulation of continuous and discrete time systems such as process plants. The authors begin by briefly stating some requirements of simulation from the point o...
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Concerned with the use of object-oriented systems in the simulation of continuous and discrete time systems such as process plants. The authors begin by briefly stating some requirements of simulation from the point of view of data modelling and management. They then examine how the notion of objects as used in the object-oriented community provides the necessary support or otherwise for these requirements, arguing against the merits of encapsulation in simulation. They show that the difference between an object-oriented data model and a semantic data model is precisely in their degrees of encapsulation, i.e. an object-oriented data model without encapsulation is a semantic data model. They propose that DB-Prolog (C. Tan et al., 1989) with its powerful and flexible semantic data model and a seamlessly integrated declarative query facility is well suited to simulation.< >
Presents a survey of an object-oriented approach to parallel computing, followed at Philips Research Laboratories, Eindhoven, in ESPRIT project 415. The results that are strived for at the end of this five year projec...
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Presents a survey of an object-oriented approach to parallel computing, followed at Philips Research Laboratories, Eindhoven, in ESPRIT project 415. The results that are strived for at the end of this five year project, carried out within ESPRIT project 415, are: (1) A prototype Decentralized object-oriented Machine, DOOM, consisting of some 100 identical self-contained computers, having a CPU, local memory and communications means, which are connected in a direct packet switching network. Each computer, called a node of the system, has a copy of the operating system kernel. This kernel performs local resource management, and cooperates with the other kernels for global operating system tasks. The prototype DOOM system is connected, as a satellite, to a host computer, where the programming environment resides. (2) A Parallel object-oriented Language, POOL, in which significant application programs can be programmed. The languages provides the user with control of parallelism and granularity. (3) Two significant applications in the area of symbolic processing that demonstrate the performance increase through parallelism on DOOM. The first of these is a parallel theorem prover, applied to the verification of VLSI circuit designs. The second is a parallel version of the analytical component of the Rosetta natural language translation system.< >
Discusses the IDAS project, a collaborative project investigating and developing an intelligent documentation advisory system (IDAS). The authors' aim is to develop intelligent on-line technical documentation, pre...
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Discusses the IDAS project, a collaborative project investigating and developing an intelligent documentation advisory system (IDAS). The authors' aim is to develop intelligent on-line technical documentation, presented via hypertext with natural language generation and constructed dynamically by expert systems technology using object-oriented techniques. The IDAS being designed is targeted at users of an automatic test equipment (ATE) system and aims to replace part of the current paper-based documentation. The IDAS will represent the ATE using a qualitative model at a level close to linguistic realisation and implemented in an object-oriented framework. It will then display material to the user via a hypertext interface, but where the contents and connectivity of the hypertext nodes are partially determined dynamically according to the system's knowledge of the user's and their goals. In this way, it is hoped to improve on standard hypertext systems, by giving responses which take account of the users problem, skills and privilege.< >
LabStation is a general purpose instrument integration and laboratory automation CASE tool. It provides a total operating and development environment on top of the PC's operating system. LabStation is unique as an...
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LabStation is a general purpose instrument integration and laboratory automation CASE tool. It provides a total operating and development environment on top of the PC's operating system. LabStation is unique as an instrument interfacing tool as it provides a total solution to the problem of acquiring data from instruments and transferring it to a LIMS. Unlike most PC based systems that can only acquire data from a single instrument, LabStation can control and acquire data from a number of instruments concurrently. It can also perform background communication with a LIMS running on a remote host. LabStation is multitasking and event driven. In order to accomplish these programmingobjectives, LabStation uses the object orientated programming paradigm. The author introduces the LabStation environment, provides details on the usage of the standard system, and gives details of the various data acquisition methods that are possible.< >
Many object-oriented methodologies give the impression that the process of taking a completed design and implementing it is mechanistic, even trivial. Instead software engineers find in practice that there are a large...
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Many object-oriented methodologies give the impression that the process of taking a completed design and implementing it is mechanistic, even trivial. Instead software engineers find in practice that there are a large number of decisions still to be taken even after the specification and design are complete. This is particularly true when the implementation language for the product is designed to allow the widest possible range of implementation choices; so it is particularly true when the implementation language is C++. This paper describes some of the implementation issues faced by one project, and examines some of the additional personal role that aided their resolution. The project under development was an embedded system performing protocol conversion and database caching, part of a network management system.< >
The issue of reverse engineering to an objectoriented representation is examined; a particular contention is whether the objectoriented world of data and associated procedures is a realisable target. It is shown tha...
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The issue of reverse engineering to an objectoriented representation is examined; a particular contention is whether the objectoriented world of data and associated procedures is a realisable target. It is shown that the problem becomes one of identifying entities which can be encapsulated, rather than the usual one of separating process from data. The requirement for a neural network and rule based mechanism for function extraction is identified. A high level and non-rigorous approach for movement to an objectoriented form is illustrated.< >
A software tool is described that allows a wide variety of digital radio links to be modelled at varying levels of detail. It comprises a library of some 300 C/sup ++/ classes residing within another tool that provide...
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A software tool is described that allows a wide variety of digital radio links to be modelled at varying levels of detail. It comprises a library of some 300 C/sup ++/ classes residing within another tool that provides features applicable to a wide range of modelling problems such as parameter handling, graphics facilities and simulation control, as well as a basic graphical user interface. The structure of the class library and the construction of models are described. Examples of particular modelling problems show the benefits of the objectoriented approach.< >
A new and developing area in human-computer interaction is that of the synthetic environment or virtual workstation. This is where an operator, wearing a display device on his head, is presented with suitable sensory ...
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A new and developing area in human-computer interaction is that of the synthetic environment or virtual workstation. This is where an operator, wearing a display device on his head, is presented with suitable sensory information simulating a desired situation. To accomplish this, aside from the complex technological problems of creating all of the appropriate sensations for the operator, methods must be found to represent the imaginary world within which he sits. At present, the most suitable candidate for handling with this problem is the object orientated programming approach. A simple introduction to this, with particular reference to this problem, is given. A current scheme for object representation is also discussed.< >
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