摘要:

In the procuring of equipment for defence, an ‘acquisition triangle’ can be discerned in that the Government is the customer, an industrial base is the supplier, and an armed service is the operator. The process of procurement is illustrated by reference to three weapon systems: airborne early warning radar, torpedoes and surface warships. The paper traces case histories of specification, design and development of systems in these three areas and points out the advantages of a systems approach to specification, design, development and deployment. The paper assesses the needs for increasing technical knowledge and expertise in members of the armed services and concludes with an explanation of the necessity for compromise in Government-financed research and development.

DOI:10.1049/ip-a-1.1986.0001

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The UK continues to be among the leading countries in terms of scientific innovation, but its failure to exploit successfully the results of good research has often been cited in the past decades. Professional engineers must play a role throughout all phases of new product introduction, including particularly the marketing task which has, hitherto, been inadequately recognised. The management of the total task of new product introduction from market study through product concept, design, development and production also needs closer attention from the professional engineer whose ‘formation’ should include the relevant elements. All innovations bring attendant risks of possible delays and excess costs during the development phase. Successful and profitable introduction of new products demands a compromise between market need and scientific creativity, requiring, at all stages, decisions to be made by engineers skilled in risk management. Evolution rather than revolution should be the order of the day. As a demonstration of the principles, the introduction of a new medical linear accelerator for cancer therapy is described. A Linac is a complex machine embracing many engineering disciplines, but which receives scant attention in the engineering literature. It is required to deliver controlled doses of high-energy photons or electrons in the range 4–20 MeV. Some elements of the introduction of the new MEL/Philips SL25 are described, with particular reference to the innovations, such as the beam bending magnet and overall control system. The relevance of the principles for successful product innovation to this practical case are examined.

DOI:10.1049/ip-a-1.1986.0002

出版商:IEE    

年代:1986

数据来源: IET

摘要:

About 50 years ago, during the year 1935, decisions were taken which led to the establishment, in the UK, of the world's first, public, regular, high-definition, all-electronic television system. The first suggestion for transmitting images (of printed texts) from one place to another was made by Bain in 1843. Subsequently Bakewell (1848), Caselli (1862), Meyer (1869), d'Arlincourt (1872) and others devised methods which enabled images of maps, diagrams, messages and sketches to be sent from one place to another. However the early commercial ventures were not a success. The discovery in 1873 of the photoconductive effect of selenium led to numerous suggestions for ‘seeing by electricity’ but the first demonstration of rudimentary television was not given until over 50 years later when Baird, in 1925, succeeded in transmitting and receiving low-definition images. In both the UK and the USA, particularly, various aspects of low-definition television were demonstrated, principally by Baird and Bell Laboratories. By the late 1920s it was evident that such television could not give rise to a generally acceptable television service. From c.1930, the Radio Corporation of America (RCA) and Electric and Musical Industries (EMI) undertook extensive investigations on all-electronic television systems. The paper outlines some of the factors which led to the birth of the British 405-line television station at Alexandra Palace in 1936.

DOI:10.1049/ip-a-1.1986.0003

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The mechanism of plasma and projectile acceleration in a DC rail gun is described from a microscopic point of view through the establishment of the Hall field. The plasma conductivity is shown to be a tensor, indicating that there is a small component of current parallel to the direction of acceleration. The plasma characteristics are evaluated in the experiment of Baueret al.as a function of plasma mass through a simple fluid mechanical analysis of the plasma. By equating the energy dissipated in the plasma with the radiation heat loss, the properties of the plasma are determined.

DOI:10.1049/ip-a-1.1986.0004

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The paper contains a brief review of the various techniques employed for the sampling of RF and microwave signals, and reference is made to subharmonic sampling as one of the possible applications. Particular attention is given to the two- and four-diode gate arrangements and the associated pulse strategies for fast switching time are discussed, as are the theoretical and practical aspects associated with the use of finite risetime sampling pulse trains. The design and operation of an experimental 10 GHz GaAs FET unit are given in detail, and recommendations are given in the concluding Section as regards development effort in sampling gates.

DOI:10.1049/ip-a-1.1986.0006

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The conditions under which more than one stable electric discharge can be operated so as to interact electromagnetically have been investigated with arc discharges at currents of 10-2100 A in air and argon at atmospheric pressure, and with glow discharges at currents of the order of 10 mA-2.4 A at pressures from 100 Pa to atmospheric pressure in air, argon and CO2laser gas mixtures. A wide variety of electrode configurations are possible, many of which have not been described before. Operation with parallel (attracting) discharges and antiparallel (repelling) discharges from the same and separate supplies is described and the conditions for stable operation analysed. The principles are applicable to almost all uses of electric discharges, including high-current water-cooled electrodes for use in arc furnaces and plasma furnaces; low- and high-pressure discharge lamps, CW gas lasers and spark plugs.

DOI:10.1049/ip-a-1.1986.0007

出版商:IEE    

年代:1986

数据来源: IET

摘要:

Four methods of managing the radio spectrum are considered as possible solutions to the problem of a shortage of useful spectrum, which has arisen with the growth of demand due to rapid developments in electronics. The objectives of the solution to this problem and the choice between the methods are analysed by a six-step methodology defined by Sir John Hoskyns. The constraints arising from technical limitations, international obligations and social factors are included in the analysis. The first method is the current method in the UK; it was criticised in the Merriman Report in 1983. The second would be based on cost-benefit analyses, but the conceptual and economic bases are too indefinite for it to be applied. The other two invoke the disciplines of price mechanisms to induce the users to adopt technical and operational improvements to reduce their demands, either in a free market or under a continuing central authority charging rents for spectrum assignments, depending on the amount of spectrum demanded and the strength of competing demands. The renting method is less hampered by the technical and international constraints than a free market. Publication of the rents and the method of calculation are essential features.

DOI:10.1049/ip-a-1.1986.0008

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The paper presents an analysis of quality circle questionnaire surveys for organisations in the electrical engineering and electronic sector. The findings indicate that there are few major differences on the setting up and operation of circles in this sector when compared to other industries. The main differences centre around a seemingly greater awareness of the contribution of circles as part of the specific long-term company commitment to quality, and a larger number of white collar or staff circles in this industry than in any other studied. It is shown that the introduction of circles must be thorough, enthusiastic with positive commitment from top decision makers, and that rigid rules cannot be applied; the concept must be tailored to suit the philosophy and culture of the respective company. The issues relating to circle failure are also discussed, with the main reasons for failure being labour turnover, redundancies and/or restructuring, lack of co-operation from middle management and circle leaders lacking the time to organise meetings.

DOI:10.1049/ip-a-1.1986.0009

出版商:IEE    

年代:1986

数据来源: IET

摘要:

The papers of four contributors to the Colloquium ‘From new technologies to profitable products’ are presented. They discuss the advantages and disadvantages of new technologies, their exploitation, intercept strategy and funding, through to new products. The discussion at the Colloquium is summarised, concluding with the importance of timing, the product brief and the need for profitable products.

DOI:10.1049/ip-a-1.1986.0010

出版商:IEE    

年代:1986

数据来源: IET