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T he technological prowess of the U nited S tates was symbolized by what became known as the space shuttle, which the National Aeronautics and Space Administration (NASA) began to work on in the late 1960s. With the shuttle program NASA planned to facilitate its aggressive space-exploration effort by providing low-cost, reusable transportation to and from Earth's orbit. NASA officials compared the space program's traditional use of expendable launch vehicles to throwing away a railroad locomotive after every train trip, whereas a reusable shuttle would offer cost-effective, routine access to space. Approval of the shuttle initiative required complex political maneuvering by NASA and its supporters between 1969 and 1972. The twists and turns in the approval process actually shaped the final direction that the shuttle program took, demonstrating the pitfalls of decision making by compromise and the challenges of managing large-scale technology programs within the federal government.1 相似文献
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Roger D. Launius 《History & Technology》2013,29(3):225-255
By focusing on the key book‐length studies of the Apollo program that landed American astronauts on the Moon in the 1960s and 1970s, this essay seeks to evaluate the historiography about Apollo in the first decade of the twenty‐first century, dividing the subject into five major areas. The first area is the foreign policy and public policy antecedents of Apollo and its immediate ramifications; some of these efforts have yielded significant studies. The second area involves the evolution of space hardware, in many instances these are overwhelmingly detailed studies of rockets and other space flight technologies. Third, there is a great fascination with the astronauts and their actual flights, and a rich tradition of memoir and narrative exists in this arena. The fourth area receiving attention from historians of Apollo and the lunar voyages emphasizes the history of science, in which much of the focus is on the scientists, scientific findings from the voyages of discovery, and the use of this evidence in developing larger theories about the origin and evolution of the solar system. Finally, and increasingly so in the last 20 years, the Apollo story has been recontextualized through social and cultural investigations of its meaning in modern America. Assessing the five major areas enumerated above, this essay also offers some possibly fruitful avenues of future research. 相似文献
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Roger B.J. Benson Erich M.G. Fitzgerald Thomas H. Rich Patricia Vickers-Rich 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):456-461
Benson, R.B.J., Fitzgerald, E.M.G., Rich, T.H. & Vickers-Rich, P., 2013. Large freshwater plesiosaurian from the Cretaceous (Aptian) of Australia. Alcheringa 37, 1–6. ISSN 0311-5518We report a large plesiosaurian tooth from the freshwater early–middle Aptian (Early Cretaceous) Eumeralla Formation of Victoria, Australia. This, combined with records of smaller plesiosaurian teeth with an alternative morphology, provides evidence for a multitaxic freshwater plesiosaurian assemblage. Dental and body size differences suggest ecological partitioning of sympatric freshwater plesiosaurians analogous to that in modern freshwater odontocete cetaceans. The evolutionarily plastic body plan of Plesiosauria may have facilitated niche differentiation and helped them to exclude ichthyosaurs from freshwater environments during the Mesozoic. However, confirmation of this hypothesis requires the discovery of more complete remains.Roger B.J. Benson [roger.benson@earth.ox.ac.uk], Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK; Erich M.G. Fitzgerald [efitzgerald@museum.vic.gov.au], Thomas H. Rich [trich@museum.vic.gov.au], Museum Victoria, GPO Box 666, Melbourne, Victoria 3001, Australia; Thomas H. Rich and Patricia Vickers-Rich [pat.rich@monash.edu], School of Geosciences, Monash University, Clayton, Victoria 3800, Australia. Received 30.10.2012; revised 27.1.2013; accepted 31.1.2013. 相似文献
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Roger Absalom 《Journal of Modern Italian Studies》2013,18(4):413-425
Abstract The little-known ‘great escape’ of Allied prisoners-of-war (some 50,000) held in Italian camps at the time of the armistice of 8 September 1943 provides the starting-point for a fresh interpretation of popular and peasant experience during the emergency of 1943 – 5. The article explores some of the main aspects of the ‘strange alliance’ between Allied fugitives and the Italian population, with particular attention to the mutual symbolic appropriation between former ‘enemies’ in the midst of a civil war and related collapse of the state. 相似文献
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Richards et al. (2000) reconstructed the diet of the human remains found in Gough's and Sun Hole Cave through isotope analysis. They concluded that these people consumed an entirely terrestrial-based diet. Their reconstruction was based upon comparison of the results from human bones with those from a very small number of associated animals. The diets of the Gough's and Sun Hole Cave human were different from the other six Upper Palaeolithic humans from the British Isles for which dietary information has been obtained through isotope analysis. The work of Richards et al. (2000) suggests that they were the only ones for whom marine or freshwater resources did not play a significant role in their diets. We test this through further analyses of faunal remains from Gough's Cave, Sun Hole and other contemporary sites (Kent's Cavern, Aveline's Hole, Kendrick's Cave). Despite the limited faunal sample, the original palaeodietary reconstruction is broadly consistent with our findings. The isotope values of the main protein sources consumed by the humans from both sites are consistent with those of red deer and bovines, and, for a single individual, with that of horse and red deer. Reindeer was postulated in the original reconstruction as a potential food source, but this seems very unlikely based on our isotope reconstruction and the archaeological remains. 相似文献
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