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President, Charles S. Goldman, M.P.; Chairman, Charles Bathurst, M.P.; Vice‐Presidents: Christopher Addison, M.D., M.P., Waldorf Astor, M.P., Charles Bathurst, M.P., Hilaire Belloc, Ralph D. Blumenfeld, Lord Blyth, J.P., Colonel Charles E. Cassal, V.D., F.I.C., the Bishop of Chichester, Sir Arthur H. Church, K.C.V.O., M.A., D.Sc., F.R.S., Sir Wm. Earnshaw Cooper, C.I.E., E. Crawshay‐Williams, M.P., Sir Anderson Critchett, Bart., C.V.O., F.R.C.S.E., William Ewart, M.D., F.R.C.P., Lieut.‐Colonel Sir Joseph Fayrer, Bart., M.A., M.D., Sir Alfred D. Fripp, K.C.V.O., C.B., M.B., M.S., Sir Harold Harmsworth, Bart., Arnold F. Hills, Sir Victor Horsley, M.D., F.R.C.S., F.R.S., O. Gutekunst, Sir H. Seymour King, K.C.I.E., M.A., the Duke of Manchester, P.C., Professor Sir Wm. Osler, Bart., M.D., F.R.S., Sir Gilbert Parker, D.C.L., M.P., Sir Wm. Ramsay, K.C.B., LL.D., M.D., F.R.S., Harrington Sainsbury, M.D., F.R.C.P., W. G. Savage, M.D., B.Sc., R. H. Scanes Spicer, M.D., M.R.C.S., the Hon. Lionel Walrond, M.P., Hugh Walsham, M.D., F.R.C.P., Harvey W. Wiley, M.D., Evelyn Wrench.
IF a test bed is available the test should be preferably carried out on this, where the power given out by the engine may be more easily measured. If, however, this…
IF a test bed is available the test should be preferably carried out on this, where the power given out by the engine may be more easily measured. If, however, this equipment is not available the test must be carried out in the aircraft, but for the test under these conditions a “known” airscrew must be available. This airscrew should not be the one normally used on the aircraft, but one that has been modified (and calibrated) to allow the engine to be run up to its full r.p.m. The reason for this is that the flight airscrew, for aerodynamic reasons, docs not allow the engine to reach its full r.p.m. with the aircraft stationary on the ground, and unless a “test” airscrew is used an engine may be sent into the air with a defect which may only make itself apparent at the higher r.p.m. Pilots should not be asked to take this risk.
THE syllabus issued by the Air Ministry stipulates that the qualifications required to be held by the candidate for a ground engineer's licence in “C” category are: (1) an…
THE syllabus issued by the Air Ministry stipulates that the qualifications required to be held by the candidate for a ground engineer's licence in “C” category are: (1) an intimate knowledge of the constructional and assembly details of the engine to be included in the licence; and (2) the installation, operation, and maintenance of that engine in an aircraft. This specialised knowledge must be obtained by practical experience in the engine shop, aircraft shop, and on the aerodrome, and proofs of actual engagement in these spheres will be required by the Air Ministry Examining Board.
Well‐founded complaint has recently been made concerning the characters of the various forms of “candy,” or, as we should term them, “sweets,” that are manufactured in great quantities in the United States.
The Care and Maintenance of Aircraft. Second Edition. By Various Authors. (Airways Publications, Ltd., 3s. 6d.). The fact that a second edition of a technical work of this…
The Care and Maintenance of Aircraft. Second Edition. By Various Authors. (Airways Publications, Ltd., 3s. 6d.). The fact that a second edition of a technical work of this nature was called for within three months of the publication of the first is its own testimony to the value of the contents.
The paper targets on providing new experimental data for validation of the well-established mathematical models within the framework of the lattice Boltzmann method (LBM)…
The paper targets on providing new experimental data for validation of the well-established mathematical models within the framework of the lattice Boltzmann method (LBM), which are applied to problems of casting processes in complex mould cavities.
An experimental campaign aiming at the free-surface flow within a system of narrow channels is designed and executed under well-controlled laboratory conditions. An in-house lattice Boltzmann solver is implemented. Its algorithm is described in detail and its performance is tested thoroughly using both the newly recorded experimental data and well-known analytical benchmark tests.
The benchmark tests prove the ability of the implemented algorithm to provide a reliable solution when the surface tension effects become dominant. The convergence of the implemented method is assessed. The two new experimentally studied problems are resolved well by simulations using a coarse computational grid.
A detailed set of original experimental data for validation of computational schemes for simulations of free-surface gravity-driven flow within a system of narrow channels is presented.
This study examines the durations of US stock market cycle expansions and contractions for the presence of seasonality. Specifically, it is determined whether the…
This study examines the durations of US stock market cycle expansions and contractions for the presence of seasonality. Specifically, it is determined whether the distributional characteristics (i.e., location and dispersion) of the durations of market expansions and contractions are dependent on the time of the year the market phase begins or ends. The duration data are obtained from a stock market chronology of monthly peak and trough dates for the period May 1835 through July 1998 and nonparametric rank‐based tests are used to test for the presence of seasonality. In order to provide some evidence on robustness with respect to the sample data, results are obtained for the entire sample period as well as for various sub‐periods. When the data are aggregated on a quarterly basis, the evidence suggests that seasonal structures are present in stock market cycle durations. These seasonals are related primarily to shifts in location over the course of the year and to when a market expansion or contraction begins. However, when the duration data are aggregated on a bi‐annual basis, support for seasonality is much more limited.
This chapter documents an exchange between Leonard Savage, founder of the subjective probability approach to decision-making, and Karl Popper, advocate of the so-called…
This chapter documents an exchange between Leonard Savage, founder of the subjective probability approach to decision-making, and Karl Popper, advocate of the so-called propensity approach to probability, of which there is no knowledge in the literature on probability theory. Early in 1958, just after being informally tested by Daniel Ellsberg with a test of consistency in decision-making processes that originated the so-called Ellsberg Paradox, Savage was made aware that a similar argument had been put forward by Popper. Popper found it paradoxical that two apparently similar events should be attributed the same subjective probability even though evidence supporting judgment in one case was different than in the other case. On this ground, Popper rejected the subjective probability approach. Inspection of the Savage Papers archived at Yale University Library makes it possible to document Savage’s reaction to Popper, of which there is no evidence in his published writings. Savage wrote to Popper denying that his criticism had paradoxical content and a brief exchange followed. The chapter shows that while Savage was unconvinced by Popper’s argument he was not hostile to an axiomatically founded generalization of his theory.
RELIEF, which came to Europe in the early morning of September 30th, will be felt no more keenly anywhere than in libraries. Since Richard de Bury implored peace because war was the worst enemy of the book, we have had reason to know for ages what war may mean for our collections. Already, indeed, library staffs had been drawn upon for service in the Forces, in Air Raid Precautions and other urgent war work and some have not returned to their usual places yet. In the last war the proceedings began for libraries with drastic retrenchments and these were restored only when it was found that even at such a time the book was a necessity and not a superfluity.
LONG before man learnt to make fire by the friction of wood, he experienced the burden of friction in dragging home his kill. Perhaps it is not too fanciful to suppose…
LONG before man learnt to make fire by the friction of wood, he experienced the burden of friction in dragging home his kill. Perhaps it is not too fanciful to suppose that the torn sides of his beast gave the first solid lubricant. Blood and mutton fat were seriously recommended as lubricants for church bell trunnions as recently as the 17th century. Indoed we still reckon fatty acids the best of all boundary lubricants. The range of man's activities has increased enormously in the present century, and particularly in the last few decades. Men have circled the earth in space; a space ship is on its way to examine another planet; terrestrial man is boring to the bottom of the earth's crust; others have descended to the depths of the ocean, and oven established a home on the floor of the Mediterranean, Speeds have increased by factors of thousands, temperatures range from near absolute zero to thousands of degrees; and a new environment of high‐intensity nuclear radiation has been created. Still, objects must move over and along each other in these exotic conditions; and to a large extent solid lubricants can provide the answer to the frictional problems.