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201.
Erik Trinkaus Ji
í Svoboda Dixie L. West Vladimír Sldek Simon W. Hillson Eva Drozdov Miriam Fi
kov 《Journal of archaeological science》2000,27(12):1115
The excavation and palaeoanthropological analysis of the early Upper Palaeolithic site of Dolní V
stonice II has yielded a series of incomplete and isolated human remains, comprising cranial vaults, teeth (including a series from an infant), ribs, arm bones, hand phalanges, leg bones, tarsals, metatarsals and pedal phalanges. Morphologically and morphometrically the elements are similar to those from buried individuals at Dolní V
stonice I and II and Pavlov I, as well as to other European early Upper Palaeolithic human remains. They differ principally in the high percentage of cortical areas of the distal humerus and femur. The Dolní V
stonice 36 infant's teeth may well derive from an undisturbed burial with in situ bone destruction. Geological processes are unlikely to have produced the taphonomic patterns observed, and the preservation and damage patterns of the elements (other than Dolní V
stonice 36) suggest that the original bodies were processed by some combination of scavenging agents. Moreover, the original number of burials at Dolní V
stonice II may have been greater than the four currently known. 相似文献
202.
203.
Separating two or more aspects of an object via cutting was likely an important factor in the origin and evolution of flaked stone technology. In recent years experiments have demonstrated that several stone tool attributes can influence different kinds of cutting behaviour: slicing, cleaving, scraping, sawing, drilling, piercing and abrading. Here we experimentally assessed the role of stone flake plan- and profile-view gross-edge curvature in a controlled slicing task. We also assessed the role of edge length. A total of 21 participants, using 252 stone flakes with distinct gross-edge curvatures and edge lengths, were asked to cut through a standardized substrate, and their efficiency in the task was measured over time. Flakes with longer edge lengths increased the efficiency of the cutting task, but increasing either plan- or profile-view edge curvature decreased the efficiency of the cutting task. These results have implications for the emergence of particular tool forms or reduction sequences throughout the Pleistocene, and may in part explain why certain forms were favoured by Paleolithic people, leading to their convergent evolution or widespread transmission. 相似文献
204.
China's exports success has implications for regional income inequality, because most of its export products are manufactured in the coastal zone. We propose a value chain-based accounting framework to quantify the contributions of exports to regional income inequality. We employ newly developed interregional input–output tables for China, which distinguish between processing export activities and ordinary export activities. We analyze the period 2002–2012, the decade during which China became the “Factory of the World.” We find that an RMB of processing exports contributed much more to regional inequality than an RMB of ordinary exports or domestic final demand. Still, changes in regional inequality (increasing in 2002–2007 and decreasing between 2007 and 2012) are much more due to rising ordinary exports in the first subperiod and the growth of domestic final demand coupled with changes in the configuration of value chains in the second. 相似文献
205.
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208.
ABSTRACT A fixed input coefficient is traditionally interpreted as the additional input from one sector that is required for an additional unit of output in another sector. It is shown that this ratio of increments is, in general, not fixed under aggregation. A tight upper and lower bound for its variation are derived. A necessary and sufficient condition for the ratio to be fixed is obtained. As a consequence, adopting the common assumption of fixed input coefficients implies that additional assumptions at any subaggregate level are required. Similar results are given for the Leontief inverse, whose typical element is usually interpreted as the additional output in one sector that is required for an additional unit of final demand in another sector. 相似文献
209.
Erik Dietzenbacher 《Journal of regional science》1995,35(3):377-390
ABSTRACT. This paper considers the bias of the matrix of multipliers when the underlying data are random. The traditional approach is to specify the stochastic nature of the input coefficients directly. It is shown that this approach implies a transactions table which is biased in a most unbalanced way. Next the practitioner's point of view, i.e., taking the transactions table as the source of random errors, is adopted. One of the results states that, within each row of the multiplier matrix, either the biases are zero, or positive biases are canceled out by negative biases in the sense that their weighted average is zero. The conditions are based on the idea that information on aggregates is more exact than information on their details. The usual asumptions of independence and unbiasedness of the individual errors are avoided. The results are shown to have a direct interpretation in connection with the RAS-updating procedure. 相似文献
210.