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Showing papers by "George Davey Smith published in 1977"


Book ChapterDOI
TL;DR: In this paper, it was shown that a free surface wave is intrinsically a subsonic phenomenon and that the set of directions on a particular anisotropic elastic half-space in which such waves can travel is determined by the slowness surface of the material.
Abstract: Publisher Summary This chapter discusses that rapid progress has been made in recent years in the investigation of the basic aspects of the theory of surface waves in anisotropic elastic media. Solutions have been found to the fundamental problems concerning the existence and uniqueness of free surface waves, and in this respect, it can be claimed that a complete theory is now in existence. The outstanding new ideas have of late come from a rather unexpected quarter—namely, the theory of dislocations and results of major significance may consequently lie hidden from specialists in the dynamics of elastic materials who do not habitually attend to developments in this field. The chapter highlights that the possibility of oversight is not reduced by the dependence of the main contributions on a multitude of sources mostly located in the literature of solid-state physics, much of the precursory material having no obvious connection with elastic surface waves. Two broad insights into the character of elastic surface waves confirmed by the present study are that a free surface wave is intrinsically a subsonic phenomenon and that the set of directions on a particular anisotropic elastic half-space in which such waves can travel is determined by the slowness surface of the material.

396 citations


Journal ArticleDOI
TL;DR: Progressive visual reaction times were measured before and after exposure of 10 subjects (anaesthetics or anaesthetic technicians) to either halothane 100-150 p.p.m. in air or air alone and there were no significant differences between the control and test situations.
Abstract: Progressive visual reaction times were measured before and after exposure of 10 subjects (anaesthetists or anaesthetic technicians) to either halothane 100–150 p.p.m. in air or air alone. There were no significant differences between the control and test situations. In a subsequent study of 15 psychology students using an audiovisual reaction time test, a tachistoscope and the Wechsler memory scale, there was no significant difference in the subjects' responses when breathing either air or a mixture of halothane 15 p.p.m. and nitrous oxide 500 p.p.m. in air (range: halothane 10.3–16.0 p.p.m., nitrous oxide 485–700p.p.m.).

52 citations


Journal ArticleDOI
TL;DR: In this paper, a computer-controlled FIM/atom probe mass spectrometer was used to measure the partitioning of alloying elements between the carbide, matrix, and interface regions of a commercial 0.8C-0.7Mn- 0.3 wt.-%Si pearlitic steel, produced by a lead patenting process.
Abstract: A computer-controlled FIM/atom probe mass spectrometer has been used to measure the partitioning of alloying elements between the carbide, matrix, and interface regions of a commercial 0.8C-0.7Mn-0.3 wt.-%Si pearlitic steel, produced by a lead patenting process. The spatial and mass resolution of the instrument permit measurement of the alloying element redistribution over small distances (< 1 nm). The analyses showed the silicon content of the matrix to be twice that of the cementite phase. The manganese level was found to be enriched in a thin (∼1.0 nm) shell at the edge of the cementite phase, while the central region of the cementite had the same manganese level as the matrix. The results of the complete analyses of each region also demonstrated the behaviour of the residual elements Cr, Ni, and Cu. Chromium partitioned to the cementite and interface regions and the residual nickel and copper had higher concentrations in the interface regions.

28 citations


Journal ArticleDOI
TL;DR: The main concern of as discussed by the authors is with the policy of positive discrimination by area in education, and with a re-examination of the educational priority idea (EPA). But I want to begin by placing this discussion firmly in the present context of cuts, and pessimism about the future prospects for education.
Abstract: The main concern of this paper is with the policy of positive discrimination by area in education, and with a re-examination of the educational priority idea (EPA). But I want to begin by placing this discussion firmly in the present context of cuts, and pessimism about the future prospects for education. For we cannot ignore these major problems and concentrate narrowly on small areas; nor in looking at national policies and priorities can we afford to neglect the local area level. It is here that the effects of such national policies are played out. Faced with cuts in educational expenditure it is reasonable that those in education should protest and fight back vigorously, particularly where what is being cut has for long been an established part of the system not some new and expensive addition. The danger is that we adopt an essentially defensive position hanging on grimly to what we have got and waiting for better times, while everybody else does the same. This would be fine, if there were strong and positive reasons to hand for educational advance and expansion, and if the present cuts were merely a temporary check on an otherwise onward and upward path. But the squeeze could not have come at a worse time for education. Many of the arguments that fuelled educational expansion in the previous decade have been seriously challenged, and the breaches not repaired. Yet we continue to use these same arguments as if nothing had happened. In that sense we have lost our way, and need to retrace our steps and study the map again. It is far from clear that 'the great debate' on education and its outcome have provided the necessary chart for navigation. To mount an effective campaign for education requires not only resistance to cuts, but positive arguments about priorities, where expenditure should be increased and services extended. We need arguments powerful enough to take on the critics of educational expansion, and challenge the crude but increasingly dominant economic theory that tends to write off public expenditure, including that on education, as a drain on resources that could otherwise be turned to more productive use, or places excessive emphasis on the link between education and the workplace, and the role of education in industrial regeneration. Arguments about priorities are the best form of defence against cuts. Merely to reassert the importance of the educational system and educational expenditure in a technological society is likely to have a declining impact. Recent performance has not matched up to expectations. Nor is the formal educational system any longer automatically central to these developments. We may well see more of the apparently paradoxical cases, where the Manpower Services Commission recruits unemployed school teachers, whom the schools cannot afford to take on, and uses them, for example, to carry out educational research in primary schools [I].

7 citations