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George Rudé 《Journal of Historical Geography》1981,7(2):188-189
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Larry V. St. Louis 《Journal of regional science》1989,29(3):373-385
ABSTRACT. This paper examines the RAS, Mc Menamin and Haring, and Lagrange-multiplier update methods in the context of the dual accounting system of the rectangular input-output model. The motivation was to determine if the additional information contained in the dual system is exploitable, while maintaining the integrity of the rectangular structure with all its advantages. Tests were conducted on the performance of the various algorithms for a derivative Leontief model relative to their performance on the rectangular structure. The results obtained for rectangular tables were generally better than those obtained for the more conventional Leontief ones. 相似文献
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ABSTRACT. Traditional models of regional diversification do not capture the trade-off between stability and living standards. In this paper, we characterize regions as open activity models subjected to both productivity and price shocks. We then partially rank small diversification policies by the direction in which they point away from the current industrial structure in mean-variance space. Some general patterns emerge. In particular, diversification for regional self-sufficiency and away from regional comparative advantage may be undesirable. 相似文献
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Lorena Grana Sonia Lanzelotti Victoria Arévalo Alvaro Yamil Tesio Nora Irene Maidana 《Archaeometry》2023,65(2):391-408
In the Andes, there are several pre-Hispanic irrigation networks with structures destined for water storage. However, it has not been widely discussed in archaeological research. This is probably due to their being difficult to identify. The aim of this study is to explore the use of diatom assemblage analysis as a methodological tool suitable to help in the identification and characterization of these ancient hydraulic structures. We analyzed two archaeological structures interpreted as water reservoirs from north-western Argentina (EH1 in Antofagasta de la Sierra and U-88R1 in Yocavil) and compared them to current reservoirs. The diatom species composition and the changes in the dominant ecological groups in the studied structures highlight different periods of hydraulic behavior. EH1 contained and stored water, but there were periods of time in which there was a lack of use or abandonment of the structure. However, the U88-R1 structure does not have diatom evidence of containing standing water for a prolonged time but presence of wet soils. Thus, the structure could have been used for other water management strategies. The results show that diatom analysis is a methodological tool with a high potential to study ancestral hydrotechnologies. 相似文献
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