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Third International Conference on Software Engineering for Real Time Systems, 1991.

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• A distributed real-time operating system

Publication Year: 1991, Page(s):260 - 265
| | PDF (344 KB)

Multiple processor systems with shared memory are used in embedded real-time systems for various applications. The authors present an approach to the development of operating systems for multiple processor systems with shared memory, assuming that memory is used for data exchange only, not for code storing. Compared to alternative approaches, this one enables faster and cheaper development of reli... View full abstract»

• Computers operating systems: V-SSTF dynamic disk scheduling technique

Publication Year: 1991, Page(s):254 - 259
| | PDF (308 KB)

V-SSTF is a new algorithm which may be turned to FCFS or SSTF by an adjustable parameter that permits the algorithm to be dynamically adapted to changing system conditions. V-SSTF and common strategies including FCFS, SSTF, SCAN, and N-step SCAN are simulated for evaluation purposes. This simulation is programmed using C language and has been implemented on NCR tower machine under Unix. It is used... View full abstract»

• Performance evaluation of movable head disk schedules

Publication Year: 1991, Page(s):250 - 253
Cited by:  Patents (1)
| | PDF (272 KB)

Several disk scheduling techniques have been suggested. It seems clear that the choice of an algorithm can make a significant difference in computer system performance, but which is best is still an open question. Therefore, the main contribution of the article is the detailed computational experience of three well-known schedulers, to evaluate their performances. The aim of the evaluation is to h... View full abstract»

• Validation methods using formal techniques

Publication Year: 1991, Page(s):244 - 249
| | PDF (372 KB)

The need for reliable software has rapidly overtaken the ability to produce it. In control applications, particularly disastrous results may arise from errors. For many years computer scientists have been developing languages and techniques to clarify the structure of programs through establishing a sound mathematical foundation. The techniques included under the general umbrella of formal methods... View full abstract»

• IEC65A control languages-a practical view

Publication Year: 1991, Page(s):139 - 144
Cited by:  Papers (1)  |  Patents (2)
| | PDF (388 KB)

Control of a manufacturing process requires the co-operation of many diverse pieces of software and hardware, from motor drives and temperature controllers through to SCADA (supervisory control and data acquisition) packages and MIS (management information services) systems. System integrators implementing a CIM (computer integrated manufacturing) system are faced with configuring and connecting a... View full abstract»

• Reusing temporal properties of real-time software

Publication Year: 1991, Page(s):7 - 15
| | PDF (540 KB)

This paper is concerned with the deterministic prediction and the reuse of temporal properties of higher order language real-time applications. It proposes a method to draw out, save, instantiate to specific hard/soft environments and finally to reuse temporal properties of software applications. The conceptual organization of a tool to support such a proposal is shown View full abstract»

• The application of parallel computing to the design of advanced helicopter flight control systems via real-time simulation

Publication Year: 1991, Page(s):104 - 108
| | PDF (328 KB)

Real-time, non-linear simulations of the dynamics of helicopter flight play a key role in the generation validation and testing of the flight control laws used in automatic flight control systems (AFCS). The purpose of the AFCS is to provide, through feedback, qualities of stability, disturbance rejection, decoupling of lateral and longitudinal motions, good pilot command tracking performance, but... View full abstract»

• The accuracy of interrupt driven time measurements

Publication Year: 1991, Page(s):217 - 220
| | PDF (212 KB)

In a number of microprocessor-based real time control and instrumentation systems interrupt service routines are used to record the time at which an event occurs. There are several applications of this technique. For example, if hardware is provided so that a voltage waveform of interest generates an interrupt once each cycle and an interrupt service routine is used to record the times at which th... View full abstract»

• An object-oriented approach to the modelling of real-time software

Publication Year: 1991, Page(s):69 - 72
| | PDF (288 KB)

Designing temporally predictable software has become a vital issue, especially in real-time industrial applications. This paper focuses on the temporal modelling problem, and discusses a method which can form the foundation of a tool which gives true temporal representation of systems. The proposed method utilizes the power of a concurrent object-oriented programming language-STRAND-using a modell... View full abstract»

• Transputer implementation of fault tolerant distributed architecture for critical real-time application

Publication Year: 1991, Page(s):239 - 243
| | PDF (260 KB)

The systems which perform mission-critical functions, as used in close-loop guidance and event sequencing for various real-time applications consider fault-tolerance as one of their desirable architectural attributes. Such systems are required to be extremely reliable and the work described is an optimistic approach to meet this reliability requirement through a communication architecture of distr... View full abstract»

• The PC' as a development environment for real time embedded systems

Publication Year: 1991, Page(s):135 - 138
| | PDF (196 KB)

Microprocessor applications consultants can be faced with the design and development of embedded systems for a diverse range of applications and client requirements. Embedded systems by their nature are hardware specific and indicate a need for dedicated development tools; however a more generalised approach often leads to an overall technically superior and more cost effective solution. The autho... View full abstract»

• Securing Ada systems

Publication Year: 1991, Page(s):1 - 6
| | PDF (252 KB)

This paper explains how the security assurance of an Ada real time embedded software system may be improved, and shows how this may have benefits for safety critical systems. The paper shows how Ada itself provides many of the features required for secure and safety critical systems. It describes a potential flaw in the architecture of an Ada system, which renders it insecure. The paper proposes a... View full abstract»

• Data point acquisition and configuration for robotic applications

Publication Year: 1991, Page(s):115 - 118
| | PDF (184 KB)

In a project implemented by BRV Ltd, it was required to program a robot to insert several different types of components into a PCB. The high number of robot positions requiring maintenance including gripper, feeder and component positions, led to a particular method for handling the positions. The components included axial resistors, cylindrical capacitors, DIL integrated circuits and SIL connecto... View full abstract»

• Parameter estimation for a non-direct drive robot arm

Publication Year: 1991, Page(s):98 - 103
| | PDF (232 KB)

One of the ways of achieving precision control at high speeds for mechanical manipulators is the identification of the parameters of the system and the use of these parameters in a controller such as model based. Viscous friction is one of the parameters whose relatively accurate estimation will lead to significant improvements in a control system. Many authors are currently researching control sy... View full abstract»

• A handwritten Arabic character recognition technique for machine reader

Publication Year: 1991, Page(s):212 - 216
Cited by:  Papers (1)  |  Patents (1)
| | PDF (292 KB)

A technique for real-time recognition of unconstrained Arabic characters is presented. The proposed technique does not require any constraints of the character forms other than limiting them to a reasonable size and orientation. Structural features, which are more suitable for handwritten character recognition, are selected. Structural features that are independent of the writer style, which are c... View full abstract»

• A reliable friend': a method for maintaining the load information in a distributed computer system

Publication Year: 1991, Page(s):63 - 68
Cited by:  Papers (1)
| | PDF (308 KB)

A very simple algorithm is proposed for maintaining the load information in a computer network supporting load balancing. With this algorithm, each node always has the identity of an underloaded node, if such an underloaded node exists at that moment. When there is a process that cannot be locally executed due to some time constraints, migration will only be attempted to that node. If that node ca... View full abstract»

• A methodology for real-time database system construction

Publication Year: 1991, Page(s):233 - 238
Cited by:  Papers (2)
| | PDF (424 KB)

A description is given of some research into well specified real-time database systems which permit analysis of the data access requirements of transactions before run-time. This enables one to do all concurrency control at system build time. Moving the concurrency control away from the run-time environment allows deterministic hard real-time scheduling of database transactions in the real-time sy... View full abstract»

• The DART real time control system

Publication Year: 1991, Page(s):86 - 92
| | PDF (404 KB)

This paper describes the radar management and real time control systems designed and developed for the demonstration of advanced radar techniques (DART) radar. The radar management computer controls the distributed radar sub-systems by a sophisticated Ethernet control network aided by real time control signals. This paper outlines the radar management, Ethernet and control hardware and describes t... View full abstract»

• A rendezvous with multitasking multiprocessors

Publication Year: 1991, Page(s):129 - 134
| | PDF (304 KB)

Controlling process plants using computers has always had spectacular failures as well as successes. A modern distributed control system (DCS) is very powerful, incorporating multitasking multiprocessors. However, unless this power is controlled, severe technical difficulties frequently arise, causing over spending and lateness. Multitasking and multiprocessing environments allow a number of appli... View full abstract»

• The effective on-line use of personal computers in conjunction with DCS for enhanced product quality and energy efficiency

Publication Year: 1991, Page(s):284 - 287
| | PDF (188 KB)

Energy represents fifteen per cent of the production costs associated with paper manufacture. In 1989 UK Paper's New Thames Mill, the UK's largest producer of high quality printing/photocopying paper, undertook a number of energy related studies using Brighton Polytechnic's Control and Dynamics Research Department for technical support. The authors detail work carried out to ascertain the extent t... View full abstract»

• A real-time validator

Publication Year: 1991, Page(s):199 - 204
Cited by:  Papers (2)
| | PDF (412 KB)

The verification and validation of representations of the evolving software artifact plays a key role in many approaches to software development. The representations range from specification and design documents to the program code itself. The authors present a real-time validator (RTV) that was developed for an application in telecommunication switching. They overview the specification model used... View full abstract»

• Symbolic Occam

Publication Year: 1991, Page(s):170 - 175
| | PDF (436 KB)

Occam is a fine grain process based programming language from the concurrent programming stable. Occam is minimal and efficient on transputers because of the hardware support for process scheduling and synchronization the hardware provides. Yet, Occam has been described as concurrent Fortran. Like Fortran, Occam is not ideally suited for symbolic, knowledge based applications. The language is infl... View full abstract»

• Real-time systems-animation prototyping of formal specifications

Publication Year: 1991, Page(s):51 - 56
Cited by:  Papers (1)
| | PDF (332 KB)

A crucial aspect of the specification process is matching what the specification says the system should do with what the client requires of the system. Many of the above approaches to software development, both formal and informal, have little regard for eliciting the clients opinions on the suitability of a specification. All require, to a greater or lesser degree, a knowledge of abstract notatio... View full abstract»

• Deriving protocol specifications from service specifications with heterogeneous timing requirements

Publication Year: 1991, Page(s):266 - 270
| | PDF (332 KB)

In a real-time distributed application, the crucial problem is the coordination between the cooperating application processes. The available resources sometimes do not suffice for installation of an underlying distributed operating system, and the inter-process coordination must be embedded directly into the application processes. An enhancement of the protocol derivation algorithm of M. Kapus-Kol... View full abstract»

• Real time control of automated adhesive dispensing

Publication Year: 1991, Page(s):145 - 150
Cited by:  Papers (1)
| | PDF (284 KB)

In order to ensure the process integrity for reliable structural adhesive joints and due to the change of adhesive viscosity with environmental variation, strict control for the dispensing process is needed. The authors present a real time control method for dispensing adhesive by using a vision sensor as a feedback controller. The system comprises a six axes robot which carries a digital controll... View full abstract»