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11.
Reappraisal of a Road Project in Iran. By Herman G. Van Der Tak and Jan de Weille. (world Bank Staff Occasional Papers, No. 7). Baltimore, Maryland: The Johns Hopkins University Press, 1969. 127 pp. $3.00.
The Economic History of the Middle East, 1800–1914: A Book of Readings. Edited by Charles Issawi. Chicago: University of Chicago Press, 1967. xv + 543 pp. $12.50 相似文献
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R. W. Thomas 《Geographical analysis》1990,22(3):209-223
The paper examines the applicability of spatial representation ideas to the determination of equilibrium solutions for multiregion disease models. In particular, alternatives to the standard specification of regionally variable infectivity rates are devised and their impact on the space-time behavior of a carrier model for Hodgkin's disease is assessed using data for Greater Manchester. 相似文献
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Brooke Kapeller Ryan Plummer Julia Baird Marilyne Jollineau 《The Canadian geographer》2023,67(3):337-351
Environmental stewardship—a concept that describes the relationships between humans and the environment—is gaining increased attention as an approach that can address planetary sustainability issues. In-depth empirical investigations of local environmental stewardship are needed to understand how social-ecological context influences stewardship, as well as the arrangement of conceptual elements in applied settings. This study addresses these needs by conducting an in-depth exploration of environmental stewardship in the Niagara Region of Canada. A single embedded case study design is employed, with environmental stewardship initiatives constituting the individual units of analysis with the case. Analysis of the spatial arrangement of a total of 89 initiatives indicated that initiatives tended to cluster closer to the Niagara River and in more populous municipalities. The significance of collaboration, tensions between the environment and economic development, and concerns about political impacts emerged as themes across contextual factors. The configuration of stewardship elements reveals interesting discrepancies between initiatives and previous stewardship research focused on larger scales, individuals, and organizations. Further analysis is encouraged to illuminate environmental stewardship in other settings as well as advance relational understanding of conceptual elements. 相似文献
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ABSTRACT. Real variable analysis has een used to great benefit in a variety of classical problems in location theory. In this paper we explore basic complex variable techniques in one formulation of the obnoxious location problem. A general definition of center points is first given and used to formulate several alternate versions of the obnoxious location problem. A logarithmic transformation is then used to demonstrate some equivalences between these families of distinct location problems (defined via center points). A prototype logarithmic potential function which results from this formulation is then investigated, and it is demonstrated that the extremal solutions with this objective reside on the boundary of its domain of definition. An application using zero- and one-dimensional centers is discussed, and a generalization to the spatial obnoxious problem is also briefly examined. We define a zero-dimensional center as a critical point of the logarithmic potential function, and it is shown that these centers are equivalent to the solutions of the Complex Moment Problem. 相似文献