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991.
E. Gliozzo D. D’Aco I. Memmi Turbanti A. Galli M. Martini E. Sibilia 《Archaeological and Anthropological Sciences》2009,1(2):77-85
Twenty-one samples of likely Roman, likely Islamic and unknown common ware from the archaeological site of Thamusida (Rabat, Morocco) were analysed in order to anchor selected types of pottery to a limited time span and, possibly, to a production
area and technology. Analytical techniques were thermoluminescence, optical microscopy, scanning electron microscopy and X-ray
fluorescence. The results arising from this research are definitely useful for the study of the site of Thamusida as well as for all researchers involved in archaeological and archaeometrical research in Morocco. Chronologies proposed
on a typological base have been denied twice: a likely Islamic cup dates back to the second century a.d.; vice versa, a stewpot, framed into the Roman period, resulted to be an eighth century a.d. production. Moreover, the identification of an eighteenth century ceramic production is of outstanding importance, as it
characterises a completely unknown production. Regarding the production area, four samples of both Roman and Islamic periods
have been recognised as local productions of Thamusida. 相似文献
992.
As evidence concerning human mobility during the transition to agriculture in central Europe, we present the results of strontium isotope analysis of human skeletons from the Neolithic village of Vaihingen, Germany. We find significantly more ‘non‐local’87Sr/86Sr values from humans buried in a Neolithic ditch surrounding Vaihingen than from those buried within the settlement. These results fit with previous studies showing a correlation between burial circumstances and strontium isotope signatures from LBK cemeteries of southwestern Germany ( Price et al. 2001 ; Bentley et al. 2002 ). A pilot study of Neolithic animal teeth from Vaihingen suggests that either ‘local’87Sr/86Sr signatures were more variable than the analysed human bones suggest, or that these domestic animals themselves were mobile, perhaps ranged by mobile pastoralists. 相似文献
993.
U‐series dating was used to determine the growth rate of a feldspar‐to‐clay weathering rind in a mid‐Holocene Cascade–Olcott tradition andesite core, and luminescence dating (last exposure to sunlight) was used to date fine‐grained feldspars scraped from the surfaces of similar buried artefacts from a 14C‐sediment‐dated archaeological site (45KI464) on the wet western slope of the Cascade Mountains of Washington. For U‐series dating, we measured 226Ra excess (226Ra excess =226Ra –230Th) in five stratigraphic depth controlled rind scrapings. 238U, 232Th and 230Th were counted by alpha spectrometry, and 226Ra and 210Pb were counted by gamma spectrometry on each sub‐sample. 相似文献
994.
Fragments of late medieval highly decorated Falke‐group stoneware have been found in excavations all over central and northern Europe. The distribution of the finds points to an origin in Saxony, but the exact centre of production is still unknown. Therefore, a set of samples has been analysed with Neutron Activation and the data compared with Saxon reference groups. The results point to production in a single workshop. The data can be clearly distinguished from all reference groups in our databank. However, the most similar group is that of Zittau, Saxony. Also, one sherd, which is typologically very similar to the Falke group, and which was made in Zittau, suggests that production was based there. 相似文献
995.
J. Buxeda I Garrigs R. E. Jones V. Kilikoglou S. T. Levi Y. Maniatis J. Mitchell L. Vagnetti K. A. Wardle S. Andreou 《Archaeometry》2003,45(2):263-284
The study of technology transfer in pottery production to the periphery of the Mycenaean world has been addressed by considering two different areas, southern Italy and central Macedonia. Technological features such as ceramic paste, decoration and firing have been determined for different ceramic groups established according to provenance criteria. The studies of technology and provenance have been performed following an archaeometric approach, using neutron activation analysis, petrographic analysis, X‐ray diffraction and scanning electron microscopy. The results have revealed the existence of two different models. On the one hand, southern Italy seems to exhibit a more organized pottery production, which follows a Mycenaean‐like technology, while in central Macedonia production is probably more varied, being based in part on the technology of the local tradition. 相似文献
996.
997.
Abstract This paper is an inquiry into the optimal allocation of time and natural areas to recreational uses, which have the feature of being a pure and continuous public good. We address this issue with a comprehensive approach. A static rational general equilibrium framework is developed in which heterogeneous agents allocate land and time endowments between alternative uses. This modeling has important advantages. First, Pareto‐optimal and voluntary‐contribution equilibrium allocations are obtained in a unified set‐up. Second, the suboptimality result of the decentralized equilibrium, the free‐rider problem on the provision of this nonexcludable public good, and different mechanisms to return the economy to its first‐best are analyzed. Finally, a methodological critique is made of some empirical literature, and it is suggested that our theoretical microeconomic‐based structure seems to be a suitable starting point for empirical research. 相似文献
998.
Gary L. Shoesmith 《Journal of regional science》2003,43(2):373-392
Abstract This study extends the work of Estrella and Mishkin (1996 , 1998 ) to show that interest‐rate spreads and probit modeling can be used to predict recessions in many states as well as the nation. State recessions are defined as two or more consecutive quarters of declining real gross state product. The yield spread, SPREAD, is defined as the difference between the 10‐year Treasury bond rate and the three‐month Treasury bill rate. The national results are similar to those obtained by Estrella and Mishkin. Probit models are estimated for all 50 states using SPREAD and unemployment insurance claims, UI, as alternative explanatory variables. For 34 of the 50 states, SPREAD is significant at the 0.01 level as a predictor of state recessions. Much weaker results are obtained using UI. Simulations for the 1979–2001 period are used to compute loss functions for the national and state models at probability screens of 30, 40, 50, and 60 percent. The results demonstrate that probit models based on SPREAD can be useful in improving business and policy decisions in many states. 相似文献
999.
1000.
Urban Growth in the 1990s: Is City Living Back? 总被引:3,自引:0,他引:3
The 1990s were an unusually good decade for the largest American cities and, in particular, for the cities of the Midwest. However, fundamentally urban growth in the 1990s looked extremely similar to urban growth during prior post–war decades. The growth of cities was determined by three main trends: (1) cities with strong human capital bases grew faster than cities without skills, (2) people moved to warmer, drier places, and (3) cities built around the automobile replaced cities that rely on public transportation. Although the negative impact of population density diminished slightly in the 1990s, there is no real evidence for a return to large, dense cities. 相似文献