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81.
García-Heras Manuel Agua Fernando Madiquida Hilario Fernández Víctor M. de Torres Jorge Villegas María-Ángeles Ruiz-Gálvez Marisa 《African Archaeological Review》2021,38(2):297-318
African Archaeological Review - A set of beads made of glass, gastropod mollusk shell, and fishbone from a Swahili occupation level on Ibo Island (northern Mozambique) is dated to the eleventh and... 相似文献
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Knowledge about the Inca measurement system is based on information from the colonial chronicles and modern studies of the 16th-century Quechua dictionaries. Based on those texts, we can presume that the Incas used an anthropometric system of measurement adopted from the proportions of the human body. Using cosine quantogram analysis and statistical verification, it is possible to verify the existence of the measurement system used by the Inca architects. For this purpose, a measurement series of architectural and water infrastructure elements were collected from 3D point cloud of the Chachabamba and Machu Picchu settlements in Machupicchu National Archaeological Park. 相似文献
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Cooper JM 《Journal of regional science》1994,34(4):563-582
The author presents an approach to the analysis of labor migration that incorporates the role of market wage variability as a source of information in individual migration decisions. "The focus...is on quantifying the effects of the origin market acting through amenities and the share of market-specific wage variability as it affects forecasts of alternative wages and forecast precision. A subsample of employed males...from the [U.S.] National Longitudinal Survey of Youth (NLS) age 16 to 22 years is used for estimation. The empirical results are consistent with the theoretically predicted relationship between migration propensities and regional differences in the information content of wages. In addition, the results provide evidence that risk aversion deters migration given uncertainty, measured by forecast precision, about alternative market wage levels." 相似文献
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A multidisciplinary programme of research on Islamic pottery has been focused on questions of the dating, provenance and technology of Islamic pottery. One particular question has been the development of stonepaste, a material made primarily of crushed quartz with added frit-glass and clay. The combination of the different approaches of this study has revealed early foundations for the technology in ninth-century AD Iraq, apparently originating in the clay ceramic rather than the ‘Egyptian faience’ tradition. Subsequent and final practice developed in tenth- and eleventh-century AD Egypt. This technology becomes the primary body for all fine Islamic ceramics. 相似文献
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This paper introduces a pattern recognizer, similar to weighting schemes used in combining time series forecasts, for use in spatial adaptive filtering applied to estimating multivariate cross-sectional models. The pattern recognizer enhances the ability to automatically detect and estimate parameters with discontinuous or sharp gradient changes over geographic contexts. Results from Monte Carlo studies suggest that the weighted spatial adaptive filter is at least as accurate as the unweighted filter for cases having smoothly changing parameters, but superior for cases having discontinuous, step-jump parameters. A case study on illicit drug-market activities using census tract-level data from Pittsburgh, Pennsylvania, further illustrates the advantages of the weighted filter. 相似文献