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81.
This paper describes the use of electron spin resonance spectroscopy to estimate the degree of heating of quartzite cobbles from hearths on the floor of the archaeological remains of an eighteenth-century Dutch colonial slave lodge. A novel technique based on the comparison of line intensities for the E’and O-2 centres in quartz distinguished successfully between cobbles which had been heated to estimated temperatures ranging from 300 °C to 450° C and controls from an adjacent stream bed. This inexpensive and simple technique could be applied to a wide range of archaeological problems involving the thermal history of objects consisting of or containing quartz. 相似文献
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ABSTRACT. This paper proposes a new method for estimating a monthly regional production model. The technique involves treating the region's monthly industrial output as a latent variable, which is in turn a function of capital (prosed by energy usage) and labor inputs. Annual observations on regional value added correspond to the summation of the unobservable monthly series over the 12 months, while changes in the national Industrial Production index help infer the series' month-to-month fluctuations. The model is estimated using the Kalman filter and the method of maximum likelihood. The estimates are used to compute monthly indices of regional value added for 15 individual 2-digit industries, and for the aggregate manufacturing sector in the Seventh Federal Reserve District. In a comparison of out-of-sample forecasting accuracy, the mixed-frequency model outperforms both the traditional parametric Cobb-Douglas and nonparametric Atlanta methods over the 1988–89 forecasting horizon. 相似文献
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Richard Barker 《International Journal of Nautical Archaeology》1993,22(2):161-165
It was a pleasure for this writer to see the two articles in IJNA , 21.4 , on John Sarsfield's Santa Clara , after following the field work that led to it, and providing many of the documentary sources from 1983. John had contacted me through the kind offices of Ruth Baker [widow of W. A. (Bill) Baker; she died last year] and I would like to record our indebtedness to that charming and knowledgeable lady, who took such interest in any extension of her husband's work. Sarsfield's work was so important that comments are here offered on the two papers (Carrell, 1992; Nance, 1992). 相似文献
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Particle induced X-ray emission (PIXE) has been used in analysis of ink and paper of the 42-line Bible and other early printed works. Results are reported and their significance discussed. 相似文献
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