摘要:

Electronic displays are being increasingly used in aircraft for the presentation of information to aircrew. This trend is due to two principal reasons, the steady improvements in the technology of electronic displays which are finding growing use in a wide range of markets, and the radical changes to the methods of distributing and processing data on board both military and civil aircraft. However, the peculiar environmental and other factors which constrain the design of airborne displays have caused the aircraft world to lag behind other markets in the use of new types of electronic display. It is the aim of the paper to review both the available and potentially promising display technologies, the human factors and environmental constraints, and the integration of the display devices into the total avionic systems, in order to present a balanced view of both the advantages and the problems associated with the use of airborne electronic displays. The design of the aircraft cockpit and the wide range of ambient light levels impose particular problems, and these are considered in relation to the characteristics of the human eye to provide some overall guidelines for display design. The types of information which are typically presented and the design of symbology are reviewed. Electronic display devices described include monochrome and colour CRTs, which are coming into use in the new generation of civil aircraft after many years of use in military aircraft, digitally-addressed CRTs, and a range of solid-state matrix and alphanumeric displays, both emissive and reflective. Image intensifiers for use in night operation are discussed. Some types of display, particularly for military aircraft, incorporate optical elements for magnification, collimation and image combination, and the use of both refractive and diffractive optial techniques is reviewed. The design of complete display systems to provide multifunction capability and protection against component failure is seen as one of the greatest potential advantages of integrating electronic displays with digital data highways.

DOI:10.1049/ip-a-1.1981.0034

出版商:IEE    

年代:1981

数据来源: IET

摘要:

Industrial electrostatics is now a well established branch of engineering, encompassing not only important applications such as electrophotography, precipitation and coating, but also the varied and unpredictable field of static hazards. Industrial environments particularly sensitive to static charge separation include the petrochemical industry, aeronautical and aerospace operations, surgical applications, pharmaceutical and synthetic-fibre manufacturing. As in most static-induced hazard situations, charge separation leading to an incendive spark illustrates well the uncontrollable nature of electrostatic phenomena. On the other hand, the application of electrostatic phenomena and the control of electrostatic processes has been developed into an extremely elegant science. Electrophotography is perhaps the best example of this, and is probably also the application which may qualify as the electrostatic process which has contributed most to changing operating routines in offices and factories worldwide. The review does not include the hazardous effects of static electricity, as this is a vast field in itself worthy of separate treatment. Indeed, some of the applications mentioned here are themselves areas where intense research efforts have been put, resulting in many volumes of published technical papers. It would be impossible to do justice to any of these topics here, and the depth of treatment is therefore limited in an attempt to reproduce what is probably more of an awareness document than an in-depth technical analysis.

DOI:10.1049/ip-a-1.1981.0035

出版商:IEE    

年代:1981

数据来源: IET

摘要:

The paper reviews the methods by which reliable processing and control can be achieved using fault-tolerant digital computers. The motivation for employing such systems is discussed, together with an indication of current and potential areas of application. The features of fault-tolerant computers are described in general terms, together with a system design procedure specific to the development of a reliable computer. The adherence to a well structured design methodology is particularly important in a fault-tolerant computer to ensure an initially fault-free system. In order to follow this design procedure an intimate knowledge of the following subject areas is required: fault classification, redundancy techniques and their relative merits and reliability modelling and analysis. These topics are covered in the paper, with particular emphasis being placed upon the implementation of hardware, software, data and time-redundancy techniques. Examples of fault-tolerant computers proposed and produced in the last decade are described. The availability of large scale integrated circuits (LSI) and in particular microprocessors will have a profound effect on the development and application of fault-tolerant computers. The implications of using LSI in this area are therefore discussed including a brief description of two fundamentally different approaches to the realisation of a fault tolerant microcomputer.

DOI:10.1049/ip-a-1.1981.0036

出版商:IEE    

年代:1981

数据来源: IET

摘要:

Various factors affecting the value and voltage dependence of the capacitance of high-voltage compressed-gas capacitors, used as high-voltage measurement standards, are considered. An experimental method for testing the mechanical stability of the electrodes is presented. Results of the comparison of a standard capacitor with other gas capacitors are presented, and it is concluded that a compressed-gas capacitor can be transported successfully if some precautions are taken.

DOI:10.1049/ip-a-1.1981.0037

出版商:IEE    

年代:1981

数据来源: IET

DOI:10.1049/ip-a-1.1981.0038

出版商:IEE    

年代:1981

数据来源: IET

摘要:

In the first part of this paper aspects of the university-industry interface are grouped on the basis of initial funding received from Government, charitable organisations, the UK University Grants Committee, the UK Science Research Council, and from private organisations and individuals. In the discussion particular emphasis is given to the units which were launched with the aid of the UK Ministry of Technology grant, 1967/68. University-owned limited-liability companies are also surveyed. The second part of the paper is a ‘case study’ of one of the successful university industrial units; this is a detailed account of the growth of Industrial Development Bangor (UCNW) Ltd. Factors predicating commercial success are analysed and evaluated. An assessment of the position of the unit within its host university is made and pointers are given to avenues of future development.

DOI:10.1049/ip-a-1.1981.0039

出版商:IEE    

年代:1981

数据来源: IET

DOI:10.1049/ip-a-1.1981.0040

出版商:IEE    

年代:1981

数据来源: IET

DOI:10.1049/ip-a-1.1981.0041

出版商:IEE    

年代:1981

数据来源: IET

摘要:

The paper reviews forms and techniques of current interruption in general, and considers the techniques, effects and implications of arc interruption in a vacuum and in gas at atmospheric or higher pressures. Arc\electrode and arc-column problems are presented, followed by treatment of the four established media for arc interruption.

DOI:10.1049/ip-a-1.1981.0043

出版商:IEE    

年代:1981

数据来源: IET

摘要:

Despite their differing aspects, and although they operate in gases at higher pressures and in nonuniform electric fields, corona discharges can be considered as glow discharges, whatever the polarity of the active electrode. Their main features are presented in the paper, together with a look at applying fields.

DOI:10.1049/ip-a-1.1981.0044

出版商:IEE    

年代:1981

数据来源: IET