scholarly journals VIII. Gaseous combustion at medium pressures. Part I. —Carbon monoxide air explosions in a closed vessel. Part II. —Methane-air explosions in a closed vessel

1926 ◽  
Vol 225 (626-635) ◽  
pp. 331-356 ◽  
Keyword(s):  
Carbon Monoxide ◽  
National Physical Laboratory ◽  
Closed Vessel ◽  
Engineering Research ◽  
The Past ◽  
Physical Laboratory ◽  
Wide Range ◽  
The Subject ◽  
Temperature And Pressure ◽  
Air Explosion

During the past five years a programme of research involving air-fuel explosions in a closed vessel has been in progress at the National Physical Laboratory for the Engineering Research Board of the Department of Scientific and Industrial Research. Among the experimental results obtained, those relating to Carbon Monoxide and Methane were considered likely to be of interest to the Society, and form the subject of the present communication. Of the two investigations described, the first gives experimental data on the respective influences of hydrogen-air and water vapour on a carbon monoxide-air explosion, and the second relates to explosions of methane and air over a comparatively wide range of initial temperature and pressure.

The Application of Computers to Life Assurance.

1961 ◽  
Vol 16 (03) ◽  
pp. 210-227
Author(s):  
T. B. Boss ◽  
K. H. Allen ◽  
A. C. Baker ◽  
D. W. Brackfield ◽  
R. B. Colbran ◽  
...  
Keyword(s):  
Study Groups ◽  
National Physical Laboratory ◽  
Computer Study ◽  
Ordinary Life ◽  
The Past ◽  
Life Assurance ◽  
Physical Laboratory

This report summarizes the conclusions reached and difficulties encountered by Group E in the discussions held over the past 4 years. It is thus an amplification and extention of the report made to a meeting of the various computer Study Groups held on 27 May 1957.The Group consists mainly of actuaries employed by ordinary life assurance offices (some composite and some purely life). The Chairman is a member of the Mathematics Division of the National Physical Laboratory, Teddington. The Group has been joined from time to time by representatives of computer manufacturers and other visitors.

Introductory remarks

1977 ◽  
Vol 280 (972) ◽  
pp. 105-105
Keyword(s):  
Climatic Change ◽  
Food Supply ◽  
Time Scale ◽  
Food Production ◽  
Rapid Change ◽  
Climatic Fluctuations ◽  
The Past ◽  
Wide Range ◽  
The Subject ◽  
Different Sources

In the last year or two there has been a remarkable increase in the interest, both popular and scientific, in the subject of climatic change. This stems from a recognition that even a highly technological society is vulnerable to the effects of climatic fluctuations and indeed may become more so, as margins of surplus food production are reduced, and nations become more interdependent for their food supply. In this respect our concern is with quite small changes - a degree (Celsius) or less in temperature and 10 % or so in rainfall. Probably we may discount some of the more alarmist suggestions of an imminent and rapid change towards near glacial conditions as these are based on very sketchy evidence. However, whatever the time-scale of climatic fluctuations with which we are concerned, we may hope to learn a great deal which is relevant to the factors which will control our future climate from the study of its more extreme vagaries in the past. Information relevant to the weather in such extreme periods is coming forward in increasing detail and volume from a wide range of disciplines. The variety of the evidence, its lack of precision as a strict measure of climate, and the number of different sources all make it difficult for an individual to build up a clear picture of past climates. However such a picture is needed, if explanations and interpretation are to be possible. Ideally one would need a synchronous picture of the climate of the whole world at selected epochs in the past. Various international programmes are directed to forming such pictures.

12.—The National Physical Laboratory—Aspects of work on the primary standards of measurement

1972 ◽  
Vol 70 ◽  
pp. 125-141
Author(s):  
J. V. Dunworth ◽  
P. Dean
Keyword(s):  
National Physical Laboratory ◽  
New Techniques ◽  
The Past ◽  
Velocity Of Light ◽  
Physical Laboratory ◽  
The Future ◽  
Primary Standards ◽  
Infrared Frequencies ◽  
Very High

One of the traditional activities of the National Physical Laboratory is its work on the maintenance and improvement of the primary standards of measurement. Although one may possibly visualise such work, because of its long history and its association with calibration services, as of a largely routine character, this is certainly far from the case at the present time. The present is a period of considerable activity and change in fundamental metrology, with the classical material standards of measurement being superseded by atomic or quantum standards. The past decade has seen a change to atomic standards for the units of length and time, and there seems little doubt that the future will see an extension of atomic-based standards to other areas, notably that of the electrical quantities. Some of the changes which may come about as a consequence of adopting the most accurate and convenient quantum methods have interesting implications. For example, a possible outcome of the new techniques being developed for the accurate measurement of very high (infrared) frequencies is that the standards of length and time may become unified, with the velocity of light taking the role of an agreed defined constant rather than an experimentally determinable quantity.

The Measurement of Errors in Gears for Turbine Reduction Drives

1947 ◽  
Vol 157 (1) ◽  
pp. 418-451 ◽  
Author(s):  
C. Timms
Keyword(s):  
Cutting Tools ◽  
National Physical Laboratory ◽  
The Past ◽  
Gear Cutting ◽  
Physical Laboratory ◽  
Gear Hobbing ◽  
Portable Instruments ◽  
The Relationship

The paper forms a review of the work carried out during the past six years at the National Physical Laboratory in connexion with the development of methods for measuring the errors of large gears for turbine reduction drives by means of a series of portable instruments. The relationship between these errors and the inaccuracies of gear-hobbing machines and gear-cutting hobs is discussed. Methods of determining these inaccuracies are described, together with information showing the improvements which have taken place in the accuracy of these machines and cutting tools resulting from the applications of the methods of testing.

Introduction: Immigration and Incorporation

1997 ◽  
Vol 40 (3) ◽  
pp. 333-338 ◽  
Author(s):  
Rubén G. Rumbaut
Keyword(s):  
United States ◽  
New York ◽  
Los Angeles ◽  
Race And Ethnicity ◽  
The United States ◽  
The Past ◽  
Immigrant Settlement ◽  
Wide Range ◽  
The Subject ◽  
American Society

In at least one sense the “American century” is ending much as it had begun: the United States has again become a nation of immigrants, and it is again being transformed in the process. But the diversity of the “new immigration” to the United States over the past three decades differs in many respects from that of the last period of mass immigration in the first three decades of the century. The immigrants themselves differ greatly in their social class and national origins, and so does the American society, polity, and economy that receives them—raising questions about their modes of incorporation, and challenging conventional accounts of assimilation processes that were framed during that previous epoch. The dynamics and future course of their adaptation are open empirical questions—as well as major questions for public policy, since the outcome will shape the future contours of American society. Indeed, as the United States undergoes its most profound demographic transformation in a century; as inexorable processes of globalization, especially international migrations from Asia, Africa, and the Americas, diversify still further the polyethnic composition of its population; and as issues of immigration, race and ethnicity become the subject of heated public debate, the question of incorporation, and its serious study, becomes all the more exigent. The essays in this special issue of Sociological Perspectives tackle that subject from a variety of analytical vantages and innovative approaches, covering a wide range of groups in major areas of immigrant settlement. Several of the papers focus specifically on Los Angeles and New York City, where, remarkably, fully a quarter of the total U.S. immigrant population resides.

Conversaziones 1955

1956 ◽  
Vol 12 (1) ◽  
pp. 9-20
Keyword(s):  
Boundary Layer ◽  
Three Dimensional ◽  
Rotating Disk ◽  
National Physical Laboratory ◽  
Turbulent Fluctuations ◽  
Research Activities ◽  
Physical Laboratory ◽  
Wide Range ◽  
Dimensional Boundary ◽  
Swept Wings

Conversaziones were held on 19 May and 28 June 1955. At the first there were thirty-six exhibits, covering a wide range of research activities. An acoustical demonstration of the instability of the laminar boundary layer on a rotating disk was given by Mr N. Gregory, Mr J. T. Stuart and Mr W. S. Walker, of the Aerodynamics Division, National Physical Laboratory. The rotating disk illustrates a phenomenon which also occurs in the flow over the swept wings of modern aircraft, the instability in the latter case being due to the growth of self-amplifying vortices in the three-dimensional boundary layer over the nose of the wing. By using a stethoscope the vibrations produced by the vortices and by the random turbulent fluctuations at the edge of the disk can clearly be heard.

scholarly journals High-frequency fatigue tests

1925 ◽  
Vol 109 (749) ◽  
pp. 119-143 ◽  
Keyword(s):  
Mild Steel ◽  
High Frequency ◽  
High Speed ◽  
Fatigue Testing ◽  
National Physical Laboratory ◽  
Fatigue Tests ◽  
Research Committee ◽  
Engineering Research ◽  
Physical Laboratory ◽  
The Cost

The experiments on high-frequency fatigue in copper, Armco iron, and mild steel described in the following paper were carried out in the Engineering Laboratory, Oxford, for the Fatigue Panel of the Aeronautical Research Committee. The cost of the apparatus was defrayed by a grant from the Engineering Research Board of the Department of Scientific and Industrial Research. In 1911 Prof. B. Hopkinson called attention to the importance of ascertaining whether the fatigue limit of metals was dependent on the rate of alternation of stress. He designed and made an electric alternating directstress machine, and published the results of tests on mild steel carried out at about 7,000 periods per minute (116 per second), which was more than three times as fast as any tests made up to that time. The results at this speed were compared with those made by Dr. Stanton at the National Physical Laboratory on the same material at 2,000 periods per minute (33 per second). Prof. Hopkinson considered that the results showed that speed had a marked effect, but he did not consider that his tests were conclusive. In the light of the knowledge gained on fatigue testing since that date neither set of tests can be considered satisfactory. The question is of importance to the users of high-speed machinery. It is also of importance when comparisons are made between tests carried out at different speeds, and, finally, it has a bearing on the causes of fatigue failure. For these reasons it appeared to be desirable to make a more thorough investigation, and, if possible, to extend the tests to very much higher speeds.

scholarly journals John Edward Lennard-Jones, 1894-1954

1955 ◽  
Vol 1 ◽  
pp. 174-184 ◽  
Keyword(s):  
Royal Society ◽  
Trinity College ◽  
National Physical Laboratory ◽  
Grammar School ◽  
Atoms And Molecules ◽  
Lennard Jones ◽  
Physical Laboratory ◽  
The Subject ◽  
The University ◽  
University Of Manchester

John Lennard-Jones was born on 27 October 1894 in Leigh, Lancashire and was educated at Leigh Grammar School, where he specialized in classics. In 1912 he entered Manchester University, changed his subject to mathematics in which he took an honours degree and then an M.Sc. under Professor Lamb, carrying out some research on the theory of sound. In 1915 he joined the Royal Flying Corps, obtained his Wings in 1917 and saw service in France; he also took part in some investigations on aerodynamics with Messrs Boulton and Paul and at the National Physical Laboratory. In 1919 he returned to the University of Manchester as lecturer in mathematics, took the degree of D.Sc. of that university and continued to work on vibrations in gases, becoming more and more interested in the gas-kinetic aspects of the subject as his paper of 1922 in the Philosophical Transactions of the Royal Society shows. In 1922, on the advice of Professor Sydney Chapman, he applied for and was elected to a Senior 1851 Exhibition to enable him to work in Cambridge, where he became a research student at Trinity College and was awarded the degree of Ph.D. in 1924. At Cambridge under the influence of R. H. Fowler he became more and more interested in the forces between atoms and molecules and in the possibility of deducing them from the behaviour of gases.

scholarly journals Some New Simpson’s-Formula-Type Inequalities for Twice-Differentiable Convex Functions via Generalized Fractional Operators

Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2249
Author(s):  
Muhammad Aamir Ali ◽  
Hasan Kara ◽  
Jessada Tariboon ◽  
Suphawat Asawasamrit ◽  
Hüseyin Budak ◽  
...  
Keyword(s):  
Convex Functions ◽  
Fractional Operators ◽  
The Past ◽  
Differentiable Functions ◽  
Simpson’S Inequality ◽  
Special Cases ◽  
Wide Range ◽  
Generalized Fractional Integral ◽  
The Subject ◽  
Formula Type

From the past to the present, various works have been dedicated to Simpson’s inequality for differentiable convex functions. Simpson-type inequalities for twice-differentiable functions have been the subject of some research. In this paper, we establish a new generalized fractional integral identity involving twice-differentiable functions, then we use this result to prove some new Simpson’s-formula-type inequalities for twice-differentiable convex functions. Furthermore, we examine a few special cases of newly established inequalities and obtain several new and old Simpson’s-formula-type inequalities. These types of analytic inequalities, as well as the methodologies for solving them, have applications in a wide range of fields where symmetry is crucial.

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