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THE purpose of this article is to present a mathematical treatment which has been found extremely useful in the design of spiral springs since it enables us to determine the physical dimensions of a spiral spring, and also its behaviour when subject to a straining action; i.e. the change of the radius of curvature at any point, change in the number of coils or in the spacing of coils. The following method concerns itself only with the spiral springs whose coils throughout the whole range of deflexion are free, i.e. do not touch one another, and also the springs which become completely solid at the maximum deflexion.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

THE great advance in aerodynamic efficiency of aircraft achieved during the last few years has largely been due to the continued efforts that have been made to reduce drag to a minimum. It is of interest, at the present stage of development, to review broadly the present state of knowledge on these matters, and to see where vital information is still lacking. It is not so long ago that we were greatly puzzled by the large differences in drag that were sometimes observed in different wind tunnels and in comparisons between results from tunnels of the compressed air type and those obtained in flight. It can now be said that the reason for these differences is well understood, but that it is not yet possible to account for them, or to predict them at all accurately, from the theory of boundary layer flow. Considering only wings with smooth surfaces the drag depends on the shape of the section, which defines the pressure distribution over its surface, and on the point at which transition from laminar to turbulent flow occurs in the boundary layer. If the pressure distribution and the transition point are known it is now possible to calculate quite closely what the profile drag will be. But theory has not yet provided a means of determining where this transition point will be on surfaces of different shapes and in air streams whose turbulence is characteristic of the wind tunnel on the one hand, and the free atmosphere on the other. The experimental determination of both profile drag and transition point in flight has done much to clarify ideas on the whole question of wing drag. It is now definitely known that the transition point may occur much further from the leading edge in the non‐turbulent atmosphere than it does in a wind tunnel at the same Reynolds number, so that the drag is lower in the former case. It is also known that this far‐back transition can occur up to Reynolds numbers as high as 17 × 106 in flight, and that its occurrence is related to the nature of the presssure gradient over the surface, that is, to the shape of the wing contour. Two important questions at once arise. Will this far‐back transition still occur on suitable sections no matter how far the Reynolds number is increased, and is it possible to encourage a still farther back transition by any alteration of section that is practically possible? The answer to these questions may well have a profound effect on design. To answer the first we must have an aeroplane capable of attaining the desired high Reynolds number and having a sufficient spanwise length of wing, undisturbed by airscrew slipstreams or discontinuities such as ailerons, to enable the measurements to be made. Such a machine docs not exist at the moment. There is some indication that the second question may admit of a favourable answer in the range of Reynolds number now available. The transition point would almost certainly be well forward on a flat plate or very thin wing section, unless, possibly, the turbulence in the air was incredibly small. In a stream such as that of the Compressed Air Tunnel it occurs practically at the leading edge at Reynolds numbers above 5 × 106. On the other hand, tests on a 25 per cent thick wing indicate a mean transition point for the two surfaces at about 20 per cent of the chord in this tunnel and, on full scale, transition as far back as 40 per cent of the chord has been observed. It seems likely that the farthest the transition could possibly move back is to the point at which a laminar boundary layer would separate from the surface. This point is calculable to a fair degree of accuracy, though the calculation has not yet been made for an aerofoil. It has been made, and the laminar separation observed experimentally, for an elliptic cylinder with axes in the ratio 3 to 1, and here it occurs at 63 per cent of the chord. The inference is that there is some hope that in non‐turbulent air it may be possible to find wing sections for which transition is delayed beyond the points hitherto observed, though how near it may prove possible to get towards the laminar separation point it is not possible even to guess.

The authors examine how physician staffing, human capital and knowledge spillovers are related to multiple dimensions of hospital operational and financial performance at the organizational level.

The authors use a data set assembled from multiple sources for more than 1,300 US hospitals and employ hierarchical linear regression to test this study’s hypotheses. The authors use multiple quality, efficiency and financial measures of performance for these hospitals.

The authors find that higher levels of staffing, skills and knowledge spillovers associated with physicians were positively associated with multiple dimensions of hospital performance. The authors find linear and nonlinear relationships between experience and performance, with the relationships primarily negative, and nonlinear relationships between spillovers and quality performance.

Hospital managers should consider increasing physician staffing levels if possible. In addition, the overall Final MIPS Score from the Centers for Medicare and Medicaid Services might be included as a factor in determining which physicians practice in a hospital. Finally, if possible, encouraging physicians to practice at multiple hospitals will likely be beneficial to hospital performance.

This study’s findings are original in that they explore how physician-specific staffing and human capital, which have received comparatively little attention in the literature, are related to several different dimensions of hospital-level operational and financial performance. To the best of the authors’ knowledge, this paper is also the first to examine the relationship between the construct of physician knowledge spillovers and hospital-level operational and financial performance.

NOT for a long time have books and libraries featured in the correspondence columns of The Times and other newspapers as regularly as they have in 1960. Earlier in the year Sir Alan Herbert's lending rights' scheme had a good run, and we have clearly not yet heard the last of it. Indeed, a Private Member's bill on the subject is to have its second reading in Parliament on December 9th. More recently, the Herbert proposals have had a by‐product in the shape of bound paperbacks, and a correspondence ensued which culminated in Sir Allen Lane's fifth‐of‐November firework banning hard‐covered Penguins for library use.

This paper examines the necessity of making compensation changes concurrently with information technology implementation that increases the requirements of incumbent jobs. The paper reviews several theoretical frameworks that highlight corollary effects of technology change on other organizational elements and underscore that organizational change programs do not occur in isolation. Following, organizational justice literature is reviewed as a theoretical background for assessing employee evaluations of, and reactions to, the absence of compensation adjustments in technology change. An organizational field study, utilizing a pretest-posttest control group design, was conducted to test a number of hypothesized effects resulting from a failure to adjust compensation for affected jobs during the implementation of a new human resource information system. The results indicated increases in perceptions of procedural injustice, distributive injustice, and dissatisfaction with the structure and administration of the compensation system. A discussion of the results and implications of the study are presented.

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry that the incomplete determinism in Nature opens to the occurrence of innovation, growth, organization, teleology communication, control, contest and freedom. The new tier to the methodological edifice that cybernetics provides stands on the earlier tiers, which go back to the Ionians (c. 500 BC). However, the new insights reveal flaws in the earlier tiers, and their removal strengthens the entire edifice. The new concepts of teleological activity and contest allow the clear demarcation of the military sciences as those whose subject matter is teleological activity involving contest. The paramount question “what ought to be done”, outside the empirical realm, is embraced by the scientific methodology. It also embraces the cognitive sciences that ask how the human mind is able to discover, and how the sequence of discoveries might converge to a true description of reality.