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Having taken up our position on the above definition of this fundamental point, which closes the long‐standing discussion between upholders of the airscrew and those of…
Having taken up our position on the above definition of this fundamental point, which closes the long‐standing discussion between upholders of the airscrew and those of the reaction system (just as in earlier days the distinction between impulse and work closed the classic discussion between the followers of Leibnitz and Descartes), we must now admit, without going into details, that this supposed attainment of equal efficiencies cannot be considered easy, if even possible, for the normal speeds of flight. It must also be admitted that a power unit, consisting of engine, compressor and jet, is at first sight a unit more complex, heavier and more bulky than the ordinary engine‐airscrew unit which has now been reduced to a high degree of simplicity and neatness. There is no doubt at all that in the sphere of the sub‐acoustic velocities the airscrew will reign supreme.
FOR the purposes of this paper the prefixes hyper and super, which, etymologically, have the same essential signification, are given different meanings: to the first a…
FOR the purposes of this paper the prefixes hyper and super, which, etymologically, have the same essential signification, are given different meanings: to the first a sense of distance, and to the second a sense of altitude.
MANY forecasts have from time to time been uttered of the ultimate possibilities of really high‐speed flying, by comparison with which the speed even of the present‐day…
MANY forecasts have from time to time been uttered of the ultimate possibilities of really high‐speed flying, by comparison with which the speed even of the present‐day Schneider Trophy seaplane would seem low. Startling prophecies have also been issued to a bewildered public of the results that might be obtainable by climbing to regions of rarefied air high above the earth's surface. But all these glimpses into the future have been in the realm of phantasy and the figures accompanying them were guesses produced by the imaginations of the authors.
Part I—The Jet Propulsion Engine IN a study of high‐speed flight presented to the Accademia dei Lincei in 1926 (G. A. Crocco, The Possibilities of Super‐Aviation, February 7th, 1926) an outline was given of the problem of ‘super‐aviation’, i.e. flight in excess of the speed of sound and made economical by operating in the stratosphere. Then in 1931 (G. A. Crocco, Aerodynamic Bodies of Negative Resistance, Rendiconti Lincei, June 12th, 1931), a jet‐reaction engine in which the external air was entrapped was described as representing a possible solution of this problem; the principle was indicated diagrammatically as long ago as 1931 by Lorin.
I WISH to thank the President and the Royal Society of Italy for the honour they have conferred by inviting me to read this paper before the 5th Volta Congress as part of a…
I WISH to thank the President and the Royal Society of Italy for the honour they have conferred by inviting me to read this paper before the 5th Volta Congress as part of a discussion on high speeds in aviation. The contributions which General Crocco has made to this subject have been valuable and stimulating. In the present paper the general question of high airscrew tip speeds is considered and the results obtained from model airscrew tests are reviewed.
DETAILS have recently been published of work undertaken at the Aeronautical Engineering School in Rome in connexion with stratospheric aero‐engines, started just before…
DETAILS have recently been published of work undertaken at the Aeronautical Engineering School in Rome in connexion with stratospheric aero‐engines, started just before the war, and more particularly on the exothermic decomposition of nitromethane as a possible fuel in such engines. (La Chim. e l'Ind. 1949, XXXI (12) pp. 436–439.) The author is R. M. Corelli of the Institute of Aeronautical Material Technology, University of Rome, who was mainly responsible for the chemical side of the research. He worked in close collaboration with Professor Gen. G. A. Crocco and Professor Ing. Luigi Crocco. The first results on a large scale were unsuccessful.
At the outbreak of the War only England, France and the U.S.A. had properly‐organised teaching and research establishments for the science of aeronautics. During the war…
At the outbreak of the War only England, France and the U.S.A. had properly‐organised teaching and research establishments for the science of aeronautics. During the war, the programme of these and other hastily‐prepared laboratories was directed to the immediate military needs, and it was not till the great strides in the development of civil aviation of ten years ago commenced that state‐aided research laboratories and professorships in aeronautics were created in a number of continental countries. Italy, energised by her new risorgimento, was one of the first to recognise the importance of setting up “schools” of research in aeronautics, and of these the Royal School of Aeronautical Engineering at Rome, with General Crocco at its head, is one of the most important. The present volume, dated rather grandiloquently from Rome “at Easter in the year VIII,” would not be called in England an “elementary” treatise. Rather, it is a complete textbook of applied aero‐dynamics which must surely cover the greater part of the syllabus “professed” at the School. Not the least important part are the hundreds (literally) of polar and drag curves of various sections, alone and incorporated in complete machines, including data with regard to slotted wings and fuselages. The majority of these emanate from the A.R.C., N.A.C.A., Göttingen and Moscow, but some are data obtained in the new laboratories at Rome itself.
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
Focusing on gender as an aspect of diversity, the purpose of this paper is to review social studies research on technology, and suggest a new direction, with gender…
Focusing on gender as an aspect of diversity, the purpose of this paper is to review social studies research on technology, and suggest a new direction, with gender redefined from a gap to be eliminated to a difference to be explored.
This paper is a literature review of research on gender, technology, and social studies from 1987 to 2007.
Previously, men had more access and used more types of technology than women, but a shift to web‐based computing eliminates some gender gaps. Women dominate online communication. Although “male” technology culture interferes with girls' self‐efficacy in schools and potential computer careers, the new Web 2.0 “participatory culture” holds promise because it relies on collaboration and networking, two well documented female strengths.
The gap notion of gender is questionable because: technology culture has been constructed as male; and social studies education, where women greatly out number men, pays little attention to gender. Evidence suggests that girls and women use technology well when it serves their interests, which may not be the same as men's. Defining gender as difference helps researchers answer calls to integrate “21st century literacies” into future studies and put gender equity at the center of future technology policy.
Very little has been written about gender as a facet of multicultural social studies education in its relation to social studies.
The purpose of this paper is to discuss why and how the notion of sustainability has been integrated to the practices of HRM in Chile. Especially, it examines how the…
The purpose of this paper is to discuss why and how the notion of sustainability has been integrated to the practices of HRM in Chile. Especially, it examines how the union‒management relationship shapes and is shaped by the adoption of a sustainable approach. By doing so, it contributes to a broader debate about HRM in Latin America.
The paper draws on a case study conducted between 2016 and 2018 in two large companies. In each of these companies, besides the analysis of internal and administrative documentation, human resource managers, line managers and union officers were interviewed.
In this paper, two main findings are discussed. First, the sustainable HRM idea installed in Chile has not involved a total renunciation of some old ideological frames, but rather an adjustment of these. The old paternalist managerialism is shaping a path to a new HRM model, willing to yield part of its control to workers, but not less unitarist in its foundations. Second, the sustainable HRM concept adoption by the studied companies is not primarily motivated by economic goals as it may have occurred in other contexts, but by the need of a solution to labour conflicts in a context of union action renewal.
This research could be used to teach about leadership, strategy and sustainability, highlighting the importance of understanding the contested nature of the employment relations within these processes of changing. To accomplish this, HR practitioners need to get more involved with pluralistic perspectives in labour relations and thus achieve effective sustainable practices in the workplace. It is also relevant that unions recognise and strengthen their ability to influence these policies.
This paper sheds lights on how the concept of sustainable HRM has been introduced in Latin America, which has been slightly discussed in mainstream scientific literature. It also provides empirical evidence about unexplored and recent changes in HRM and proposes new perspectives for the study of this topic in the region, considering variables as the managerial ideologies, current labour disputes and the relevance of trade union voice.