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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Quantitative assessment of pulmonary function

Spry, Lamorna A. January 1979 (has links)
No description available.
242

The development and diffusion of industrial robots

Zermeño-González, Ricardo January 1980 (has links)
This thesis describes the history of robots and explains the reasons for the international differences in robot '. diffusion, and the differences in the diffusion of various iobot applications with reference to the UK. As opposed to most of the literature, diffusion is examined with an integrated and interdisciplinary perspective. Robot technology evolves from the interaction of development, supply and manufacture, adoption, and promOtion. activities. Emphasis is given to the analysis of adoption, at present the most important limiting factor of robot advancement in the UK. Technical development is inferred from a comp'arison of surveys on equipment, and from the topics of ten years of symposia papers. This classification of papers is also used to highlight the international and institutional differences in robot development. Analysis of the growth in robot supply, manufacture, and use is made from statistics compiled. A series of interviews with users and potential users serves to illustrate the factors and implications of the adoption of different robot systems in the UK. Adoption pioneering takes place when several conditions exist: when the technology is compatible with the firm, when its advantages outweigh its disadvantages, and particularly when a climate exists which encourages the managerial involvement and the labour acceptance. The degree of compatibility (technical, methodological, organisational, and economic) and the consequences (profitability, labour impacts, and managerial effects) of different robot systems (transfer, manipulative, processing, and assembly) are determined by various aspects of manufacturing operations (complexity, automation, integration, labour tasks, and working conditions). The climate for adoption pioneering is basically determined by the performance of firms. The firms' policies on capital investment have as decisive a role in determining the profitability of robots as their total labour costs. The performance of the motor car industry and its machine builders explains, more than any other factor, the present state of robot advancement in the UK.
243

Development of microcomputer based foundry production control system

Sabaratnam, Sabapathy January 1982 (has links)
No description available.
244

Mechanics of rolling tube on a mandrel through two grooved rolls

Labib, Osama M. January 1982 (has links)
No description available.
245

Manufacturing, planning and control in a jobbing environment

Garner, G. E. January 1982 (has links)
No description available.
246

The formation and impact of hazard control policy : a study of the regulation of white lead paint in Britain

Williams, R. A. January 1984 (has links)
Government regulation of industrial hazards is examined in the context of the economic and technical processes of industrial development. Technical problems and costs of control are considered as factors in both the formation and impact of regulation. This thesis focuses on an historical case-study of the regulation of the hazard to painting workers from the use of lead pigments in paint. A regulatory strategy based on the prohibition of lead paints gained initial acceptance within the British state in 1911, but was subsequently rejected in favour of a strategy that allowed continued use of lead paint subject to hygiene precautions. The development of paint technology and its determinants, including concern about health hazards, are analysed, focusing on the innovation and diffusion into the paint industry of the major white pigments: white lead (PbC03 .PB(OH)2)and its substitutes. The process of regulatory development is examined, and the protracted and polarised regulatory d~bate contrasted to the prevailing 'consensual' methods of workplace regulation. The rejection of prohibition is analysed in terms of the different political and technical resources of those groups in conflict over this policy. This highlights the problems of consensus formation around such a strategy, and demonstrates certain constraints on state regulatory activity, particularly regarding industrial development. Member-states of the International Labour Organisation agreed to introduce partial prohibition of lead paint in 1921. Whether this was implemented is related to the economic importance of lead and non-lead metal and pigment industries to a nation. An analysis is made of the control of lead poisoning. The rate of control is related to the economic and technological trajectory of the regulated industry. Technical and organisational characteristics are considered as well as regulatory factors which range from voluntary compliance and informal pressures to direct legal requirements. The implications of this case-study for the analysis of the development and impacts of regulation are assessed.
247

Computer aided design and manufacture of form-rolls

Wong, Tak-Nam January 1983 (has links)
Cold roll forming of thin-walled sections is a very useful process in the sheet metal industry. However, the conventional method for the design and manufacture of form-rolls, the special tooling used in the cold roll forming process, is a very time consuming and skill demanding exercise. This thesis describes the establishment of a stand-alone minicomputer based CAD/CAM system for assisting the design and manufacture of form-rolls. The work was undertaken in collaboration with a leading manufacturer of thin-walled sections. A package of computer programs have been developed to provide computer aids for every aspect of work in form-roll design and manufacture. The programs have been successfully implemented, as an integrated CAD/CAM software system, on the ICL PERQ minicomputer with graphics facilities. Thus, the developed CAD/CAM system is a single-user workstation, with software facilities to help the user to perform the conventional roll design activities including the design of the finished section, the flower pattern, and the form-rolls. A roll editor program can then be used to modify, if required, the computer generated roll profiles. As far as manufacturing is concerned, a special-purpose roll machining program and postprocessor can be used in conjunction to generate the NC control part-programs for the production of form-rolls by NC turning. Graphics facilities have been incorporated into the CAD/CAM software programs to display drawings interactively on the computer screen throughout all stages of execution of the CAD/CAM software. It has been found that computerisation can shorten the lead time in all activities dealing with the design and manufacture of form-rolls, and small or medium size manufacturing companies can gain benefits from the CAD/CM! technology by developing, according to its own specification, a tailor-made CAD/CAM software system on a low cost minicomputer.
248

The development of a testing procedure for dry friction brakes

Hatch, Donald January 1974 (has links)
A description of the background to testing friction materials for automotive brakes explains the need for a rapid, inexpensive means of assessing their behaviour in a way which is both accurate and meaningful. Various methods of controlling inertia dynamometers to simulate road vehicles are rejected in favour of programming by means of a commercially available XY plotter. Investigation of brake service conditions is used to set up test schedules, and a dynamometer programming unit built to enable service conditions on vehicles to be simulated on a full scale dynamometer. A technique is developed by which accelerated testing can be achieved without operating under overload conditions, saving time and cost without sacrificing validity. The development of programming by XY plotter is described, with a method of operating one XY plotter to programme the machine, monitor its own behaviour, and plot its own results in logical sequence. Commissioning trials are described and the generation of reproducible results in frictional behaviour and material durability is discussed. Teclmiques are developed to cross check the operation of the machine in retrospect, and retrospectively correct results in the event of malfunctions. Sensitivity errors in the measuring circuits are displayed between calibrations, whilst leaving the recorded results almost unaffected by error. Typical results of brake lining tests are used to demonstrate the range of performance parameters which can be studied by use of the machine. Successful test investigations completed on the machine are reported, including comments on behaviour of cast iron drums and discs. The machine shows that materials can repeat their complex friction/ temperature/speed/pressure relationships at a reproducibility of the order of +-0.003u and +~ 0.0002 in. thickness loss during wear tests. Discussion of practical and academic implications completes the report with recommendations for further work in both fields.
249

Computer aided geometric design of form-rolls for NC manufacture

Ng, Koon H. January 1981 (has links)
Conventional methods of form-roll design and manufacture for Cold Roll-Forming of thin-walled metal sections have been entirely manual, time consuming and prone to errors, resulting in inefficiency and high production costs. With the use of computers, lead time can be significantly improved, particularly for those aspects involving routine but tedious human decisions and actions. This thesis describes the development of computer aided tools for producing form-roll designs for NC manufacture in the CAD/CAM environment. The work was undertaken to modernise the existing activity of a company manufacturing thin-walled sections. The investigated areas of the activity, including the design and drafting of the finished section, the flower patterns, the 10 to 1 templates, and the rolls complete with pinch-difference surfaces, side-rolls and extension-contours, have been successfully computerised by software development . Data generated by the developed software can be further processed for roll manufacturing using NC lathes. The software has been specially designed for portability to facilitate its implementation on different computers. The Opening-Radii method of forming was introduced as a subsitute to the conventional method for better forming. Most of the essential aspects in roll design have been successfully incorporated in the software. With computerisation, extensive standardisation in existing roll design practices and the use of more reliable and scientifically-based methods have been achieved. Satisfactory and beneficial results have also been obtained by the company in using the software through a terminal linked to the University by a GPO line. Both lead time and productivity in roll design and manufacture have been significantly improved. It is therefore concluded that computerisation in the design of form-rolls for automation by software development is viable. The work also demonstrated the promising nature of the CAD/CAM approach.
250

Some aspects of machinability data optimisation

Orundas, Cemal N. January 1976 (has links)
No description available.

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