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Traditional notions that family life among slaves during the pre-plantation period in the non-Hispanic Caribbean was necessarily unstable are fading in light of new research. Although marriage among this segment of the population in Caguas, Cayey, San Germán, and Yauco--rural parishes in Puerto Rico--involved only a fraction of the overall number of marriages in these communities, the marriage of slaves was much more frequent than previously assumed. Family life among the eighteenth-century Puerto Rican slave population appears to have been quite stable, as shown by the reconstruction of birth intervals for both married and unmarried mothers. Married and unmarried mothers exhibited similar reproductive behavior. These results strongly suggest that a majority of the unmarried slave mothers lived in unions that were not institutionally recognized, but that were nevertheless stable, as indicated by the high percentage of their children born at intervals comparable to those of married mothers. If unmarried mothers were living in stable consensual unions, then our understanding of these slave family units during the colonial period must be reassessed not only for Puerto Rico but possibly for the rest of the Caribbean and Latin America. 相似文献
154.
Avril M.C. Maddrell 《Journal of Historical Geography》1996,22(4):373-387
The state school curriculum, and geography in particular, played a role in encouraging emigration to the colonies, if not in actually educating for emigration. Emigration was an implicit and explicit topic in school geography, and was increasingly endorsed after the 1885 Revised Instructions to inspectors of schools which explicitly sought the promotion of emigration to young people as an “honourable enterprise”. Early-twentieth century school geography texts were part of the broader imperial discourse which valorized the settler Dominions over the tropical colonies and portrayed them as the good citizen's choice for emigration. The 1922 Empire Settlement Act represented the British government's most direct intervention in supporting out-migration from Britain, but texts at this time were generally less jingoistic than some of their forerunners, in keeping with the changed attitudes in post-World War I Britain. 相似文献
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We develop a new conceptual approach to locating inspection stations for hazardous vehicles, prevention, and compare it to the previous, punitive, philosophy of the flow-capturing location model. We implement this preventive protection philosophy with a new mixed integer program that maximizes hazard avoidance by locating a number of inspection stations to detect and remove hazardous vehicles as early in their trips as possible. We test the model's performance and analyze the spatial characteristics of solutions simulating several potential applications. Our computations demonstrate that a relaxed integer-linear program is overly demanding computationally and that a simple greedy heuristic lacks robustness. We suggest further approaches to developing more powerful and efficient solution methods. 相似文献
157.
H. MOMMSEN TH. BEIER H. DITTMANN D. HEIMERMANN A. HEIN A. ROSENBERG M. BOGHARDT E.-M. HANEBUTT-BENZ H. HALBEY 《Archaeometry》1996,38(2):347-357
Non-destructive X-ray fluorescence analyses induced by white synchrotron radiation (SYXRF) have been performed on a page of the Gutenberg Bible and 21 other different single leaves printed in the years 1470 to 1500. Absolute elemental areal densities for the papers and the inks are reported. The known high Cu and Pb content in Gutenberg's ink is confirmed. The elemental compositions of the other inks, if measurable by XRF at all, are in general very low, governed only by a few additional elements and found to be not distinctive for a known printer. This will render an identification of the printer or printing offices by ink composition analysis in the period after 1470 difficult. 相似文献
158.
Ralph M. Braid 《Journal of regional science》1996,36(2):217-234
ABSTRACT. This paper examines the socially optimal locations of branch facilities (or small stores) and main facilities (or large stores) on a finite linear market that is uniformly populated from position 0 to position 1. Each consumer has a probability w of finding the desired service (or product) at a branch facility, and a probability 1 of finding the desired service (or product) at a main facility. Two types of consumer search are considered: phone search and visit search. Different assumptions are made about the numbers of branch facilities and main facilities (each involving one or two facilities of each type). Under visit search, the socially optimal locations of branch facilities tend to be closer to main facilities than under phone search, and this tendency is more pronounced for smaller values of w. 相似文献
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ABSTRACT. In this paper a gravity model is formulated to model a hospital patient flow system. Both spatial and nonspatial measures of separation are used to estimate the model. Travel time was found to provide improved fits over linear distance in modeling patient flow behavior. Transformations of travel time (square root and log) were found to improve model performance further. Model diagnostics suggested additional spatial separation measurw, separation measure parameters demonstrated stability over time. The model is used to forecast the effects of health care financing reform and hospital closure on patient flows in an urban hospital market. Universal health coverage was found to dramatically improve access to hospital services for lower income patient populations. Hospitals at risk for closure were forecast to receive increased patient flows. Medical school hospitals are expected to lose patients after implementation of health reform, with important implications for graduate medical education. Hospital closures were shown to have negative effects on access to services in poor neighborhoods, but relatively little effect on access in the system as a whole. 相似文献