There have been a number of models proposed for integrating concurrency and object-oriented programming. Unfortunately, there have been few criteria proposed for evaluating them. In focusing on issues of inheritance, ...
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There have been a number of models proposed for integrating concurrency and object-oriented programming. Unfortunately, there have been few criteria proposed for evaluating them. In focusing on issues of inheritance, designers of new concurrent object-oriented programming languages appear to have forgotten the experiences learned from over two decades of concurrent programming. In this paper we review Bloom's criteria for evaluating the expressive power of synchronisation primitives, and apply it in an object-oriented framework. We show that most of the available concurrent object-oriented programming languages lack expressive power, and that this contributes to the so-called inheritance anomaly. We then propose a new model which does address all of Bloom's criteria. Copyright (C) 1996 Elsevier Science Ltd
Many object-based and object-oriented programming languages have no way of directly preventing structural defects due to the sharing of objects. Languages such as C++, Smalltalk and Eiffel fall into the category of un...
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Many object-based and object-oriented programming languages have no way of directly preventing structural defects due to the sharing of objects. Languages such as C++, Smalltalk and Eiffel fall into the category of unsafe object languages where these defects can and do occur. This error can be prevented by use of object languages supporting safe, strong typing structures. Examples falling into this category are Ada83 and Ada95 with their limited private, strong typing and unsharable constructs. The paper shows how unsafe object sharing is prevented using these constructs. Applications where safety and security are important should be implemented using languages in this latter category.
In the conventional object model, encapsulated objects interact by messages that result in method invocations on the destination object. A message is delivered directly at the destination object. As a result of the di...
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User or program mobility in distributed computing systems is becoming increasingly significant, since users may sometimes change their working locations. This paper proposes a Logical Machine (LM) system that can effe...
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Many languages for computer systems simulation (like GPSS and CSim) use a stochastic model of systems with the provision of adding procedural code for those aspects of the system that cannot be captured easily by a st...
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Making a finite element code easier to maintain is achieved by further modularizing it. Due to its two levels of modularity (of procedures and data), object-oriented programming is the method of choice. Its potential ...
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Real-time and on-line optimisation methods for control of large-scale systems use real-time sensor data to optimise the system's performance. The data need to be pre-processed for faults to safeguard against inapp...
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Real-time and on-line optimisation methods for control of large-scale systems use real-time sensor data to optimise the system's performance. The data need to be pre-processed for faults to safeguard against inappropriate control actions. Conventional real-time signal processing techniques are likely to fail because of the system's complexity and the processing speed required. A generic, real-time knowledge-based system-FLASH (FLexible Al for Signal Handling in real time)-has been developed to detect, diagnose and replace faulty sensor readings. Its effectiveness in processing signals for control in a complex, sensor-rich environment has been demonstrated in real-time environmental control of greenhouse microclimate. (C) 1998 Elsevier Science B.V. All rights reserved.
This paper describes the development of an intelligent process-control system for the production of fiber-reinforced organic polymeric composites. The composite material consists of a polymer matrix (polyamide resin F...
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This paper describes the development of an intelligent process-control system for the production of fiber-reinforced organic polymeric composites. The composite material consists of a polymer matrix (polyamide resin F174) and high-modulus quartz-fiber reinforcement. This composite material has good mechanical properties at high temperatures, and possesses a low dielectric constant, making it suitable for applications in missile radomes. The problem is that the raw materials are chemically reactive, and the process-control system must enable adaptation to variations in the temperature-time exposure of the raw materials and/or variations which may occur in the materials received from different suppliers. The uniqueness of the control system lies in that it is self-directing, and relies on information derived from sensors (laser fiber-optic probes and dielectric sensors) placed within the material. In addition, a materials-transformation model based on the chemical kinetics of the polymerization process calculates a number of key polymer parameters, such as degree of imidization, degree of cure, molecular weight distribution, and polydispersity ratio in situ. The collective ability to collect high-quality sensor information, to run sophisticated but robust process models in real time, to make complex decisions using artificial intelligence (AI), and to implement these decisions for controlling the structure of the actual material being processed represents a significant breakthrough in materials and process capability in this field. The focus of this work, measuring and controlling the physical and chemical properties of the material, rather than the physical attributes of the processing machinery, is an important paradigm shift. (C) 1998 Elsevier Science Ltd. All rights reserved.
作者：
Xu, DXNanjing Univ
Dept Comp Sci & Technol State Key Lab Novel Software Technol Nanjing 210093 Peoples R China
This article presents an object-oriented logic framework, I,KO, for the dependable development of knowledge based systems. Based on logical objects which are viewed as abstractions with states, constraints, behaviors ...
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This article presents an object-oriented logic framework, I,KO, for the dependable development of knowledge based systems. Based on logical objects which are viewed as abstractions with states, constraints, behaviors and nonmonotonic inheritance, a hybrid knowledge representation amalgamating rule, frame, semantics network and blackboard is available for both most structured end flat knowledge and requirements of knowledge based systems. After the iterations of specification modification and verification in terms of knowledge acquisition activities, prototypes are correctly formed. The LKO methodology, applying the concepts of rapid prototyping, top-down design and object-orientation, is designed to deal with changing and incomplete requirements and to provide multiple abstract models of the domain, where formal methods might be used at each abstract level. (C) 1998 Elsevier Science B.V. All rights reserved.
The objective of the European project STORMS (software tools for the optimization of resources in mobile systems) is to develop a software tool to be used for the design and the planning of the future universal mobile...
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The objective of the European project STORMS (software tools for the optimization of resources in mobile systems) is to develop a software tool to be used for the design and the planning of the future universal mobile telecommunication system (UMTS). In this context the ParFlow method permits the simulation of outdoor radio wave propagation in urban environment, modelling the physical system in terms of the motion of fictitious microscopic particles over a lattice. This paper gives an overview of the ParFlow method, and reports the design and the implementation of ParFlow++, an object-oriented irregular parallel software for urban outdoor radio wave propagation prediction. Copyright (C) 1998 Elsevier Science B.V.
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