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Abstract. This study implements and tests a mathematical programming model to estimate interregional, interindustry transaction flows in a national system of economic regions based on an interregional accounting framework and initial information of interregional shipments. A national input–output (IO) table, regional data on gross output, value‐added, exports, imports, and final demand at sector level are used as inputs to generate an interregional IO account that reconciles regional economic statistics and interregional transaction data. The model is tested using data from a multiregional global IO database and shows remarkable capacity to discover true interregional trade patterns from highly distorted initial estimates. 相似文献
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Abstract This study examines the indirect effects of military installations on county–level private employment, and specifically the special cases of base closure under the Base Realignment and Closure (BRAC) proceedings of 1988, 1991, 1993, and 1995. Local employment impacts are considered within a partial adjustment construct of the changes model, a specification that facilitates the decomposition of defense personnel changes into their positive, negative, and BRAC–related components. The latter two components are subsequently examined for asymmetric effects attributable to ordinary force drawdown on the one hand, and base closure on the other. Also considered are the specific effects of direct federal assistance as well as facilities conversion and reutilization within BRAC communities. 相似文献
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R. Tipping M.J. Bunting A.L. Davies H. Murray Shannon Fraser R. McCulloch 《Journal of archaeological science》2009
A methodology is described by which spatial patterns of land use were reconstructed from pollen analyses on anthropogenic sediments at a recently excavated early Neolithic timber ‘hall’ in north east Scotland. The anthropogenic sediments were from a deep, small diameter pit within the building. They present numerous taphonomic and interpretative challenges to the analyst, but from this type of deposit, the power to estimate quantitatively the vegetation structure around the archaeological site makes such difficult deposits very significant. A rigorous methodology is firstly described, therefore, by which confidence in ecological interpretation can be established. Secondly, the source of pollen in the deposit is evaluated. Thirdly, the possible pollen source area and structure of the surrounding vegetation are estimated by quantitative simulation modelling. Finally, these analyses are compared with region-scale pollen analyses from nearby conventional wetland deposits with much larger pollen source areas. The pollen assemblages recovered probably reflect land uses adjacent to the ‘hall’ and up to 2.5 km around. Cereal cultivation was the most important land use immediately around the ‘hall’, possibly grown between stands of scrub Corylus (hazel) woodland. These intensive but local-scale land uses cannot be discerned in region-scale pollen analyses. 相似文献
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Kerlijne Romanus Jan Baeten Jeroen Poblome Sabina Accardo Patrick Degryse Pierre Jacobs Dirk De Vos Marc Waelkens 《Journal of archaeological science》2009
Pitch compounds are frequently identified inside archaeological ceramic vessels. As their presence might affect the permeation of oil or wine into the ceramic fabric, experiments were conducted in which the diffusion of lipids or polyphenols into pitched and non-pitched modern vessels was followed by chemical analysis. Results show that the polyphenols of wine can intrude into the ceramics even through a pitch layer. Consequently, the absence of polyphenols in archaeological sherds is not due to their inability to reach the ceramic matrix under the pitch layer. By contrast, a pitch layer is quite effective to avoid oil intrusion into the ceramic matrix. Thus, it seems logical that oil amphorae would have been coated with pitch at the inside prior to use. Experiments in which the pitched ceramic was simultaneously exposed to oil and wine, show that the wine makes the pitch more permeable for the lipid compounds. These experimental data are confronted with residue analysis results obtained on amphorae fragments excavated in Sagalassos, Turkey. Pitch and oil were frequently found together. Based on a polyphenol test, indications for wine storage could only be obtained for two vessels. Against this background, the possible uses of the Sagalassos amphorae are discussed, and the traditional association of pine pitch with wine storage in archaeological amphorae is critically assessed. 相似文献
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Thegn N. Ladefoged Patrick V. Kirch Samuel M. Gon III Oliver A. Chadwick Anthony S. Hartshorn Peter M. Vitousek 《Journal of archaeological science》2009,36(10):2374-2383
Intensive agricultural systems interact strongly and reciprocally with features of the lands they occupy, and with features of the societies that they support. We modeled the distribution of two forms of pre-European contact intensive agriculture – irrigated pondfields and rain-fed dryland systems – across the Hawaiian archipelago using a GIS approach based on climate, hydrology, topography, substrate age, and soil fertility. Model results closely match the archaeological evidence in defined locations. On a broader scale, we calculate that the youngest island, Hawai'i, could have supported 572 km2 of intensive agriculture, 97% as rain-fed dryland field systems, while Kaua'i, the oldest island, could have supported 58 km2, all as irrigated wetland systems. Irrigated systems have higher, more reliable yields and lower labor requirements than rain-fed dryland systems, so the total potential yield from Kaua'i (49k metric tons) was almost half that of Hawai'i (97k metric tons), although Kaua'i systems required only 0.05 of the agricultural labor (8400 workers, versus 165,000 on Hawai'i) to produce the crops. We conclude that environmental constraints to intensive agriculture across the archipelago created asymmetric production efficiencies, and therefore varying potentials for agricultural surplus. The implications both for the emergence of complex sociopolitical formations and for anthropogenic transformation of Hawaiian ecosystems are substantial. 相似文献
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