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Models based on hazard functions are used to analyze spatial trends in the distance intervals separating point locations. The proportional hazards model, which has been widely applied to analyze intervals of time, is used to investigate variation in the spacing of settlements in Nebraska. This model allows spatial trends in the intervals between settlements to be investigated under very general conditions regarding the interdependence of settlement locations and permits the coordinate locations of the intervals to be treated as spatially varying covariates. An empirical analysis reveals an East-West trend in the spacing of settlements. 相似文献
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Nested multinomial logit models are used to investigate migration behavior during the 1971–74 period for a large sample of the population of Ecuador. The nested form of the model makes it possible to test hypotheses about the importance of destination characteristics in conditioning the odds for out-migration. Our empirical results indicate that the odds for migration from each origin are conditioned by the expected utilities of the available set of destinations, as well as characteristics of the origins and the personal characteristics of potential migrants. The association between destination characteristics and the frequency of out-migration allows the total volumes of migration to be adjusted to interregional differences in place-specific utilities. 相似文献
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Doreen Ellis 《政策研究杂志》1980,9(3):465-469
Romesh Diwan and Dennis Livingston, Alternative Development Strategies and Appropriate Technology
Charles Kidd, Manpower Policies for the Use of Science and Technology in Development
Robert Morgan with Ellen Irons, Eduardo Perez, Theodore Souie, and Ava Fried, Science and Technology for Development: The Role of U.S. Universities 相似文献
Charles Kidd, Manpower Policies for the Use of Science and Technology in Development
Robert Morgan with Ellen Irons, Eduardo Perez, Theodore Souie, and Ava Fried, Science and Technology for Development: The Role of U.S. Universities 相似文献
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Heather Ellis 《History & Technology》2016,32(2):120-136
AbstractIn September 1899, at the annual meeting of the British Association for the Advancement of Science (BAAS) in Dover, Guglielmo Marconi’s wireless telegraphy system was used to transmit messages across the English Channel (and across a national border) for the first time. This achievement represented a highly effective performance of scientific masculinity and constitutes a key turning point in an important struggle between competing interpretations of invention and innovation as masculine practices within British science. The British Association tended to favor a narrative of scientific research as a collectivist, international, gentlemanly-amateur pursuit, largely confined to the laboratory. Marconi, by contrast, explained the development of wireless telegraphy as the achievement of his own genius. Appealing not only to the established scientific elite but to a range of non-traditional audiences, and stressing the possibilities or ‘imagined uses’ of his technology even more so than his actual results, he succeeded in commanding unprecedented influence. 相似文献
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M. A. B. Ellis 《International Journal of Osteoarchaeology》2016,26(5):759-766
This paper presents the results of an examination of scurvy in the commingled subadult remains (minimum number of individuals = 70) of the Spring Street Presbyterian Church. This historic congregation in New York City had active burial vaults from 1820 to 1846. Scurvy is a vitamin C deficiency that results in haemorrhaging at the sites of muscle origin and insertion, particularly around the skull. These resulting lesions can occur in subadults undergoing growth, weaning and dietary stress. Applying diagnoses suggested by recent research, this article examines specific sites on the skull for lesions consistent with and suggestive of scurvy. Findings include 30 elements that display associated pathology. This population data are drawn from maxillae, sphenoids and orbits. Two osteobiographies are also presented. By connecting the biological data to the socio‐cultural environment of the church, this article raises questions of how to interpret the presence and absence of scurvy in a commingled collection. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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