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41.
A 3-D optical scanner was used to obtain precise and complete representations of lithic artifacts. A computer algorithm, which was specially developed for the purpose, was used to position the artifacts in a way which enables the extraction of the standard metric parameters (length, width, width at 1/2 length, etc.). In this way, the ambiguities which affect the traditional manual measurements were eliminated. This new methodology creates accurate and objective databases. Several other parameters (center of mass position, volume, surface area) were also computed. The advantages of our method are illustrated by the analysis of 90 scanned Lower Paleolithic handaxes.  相似文献   
42.
Optically stimulated luminescence (OSL) measurements are reported for single grains of quartz from deposits within Sibudu rock shelter. Such measurements enable rejection of unrepresentative grains and application of the finite mixture and central age models to obtain the most reliable age estimates. Three types of single-grain equivalent dose (De) distributions were observed: one sample represented a single dose population, three samples indicated mixing between Iron Age (IA) and Middle Stone Age (MSA) deposits, and 10 samples (in addition to the three mixed samples) showed scattered distributions. The latter type resulted from differences in the beta dose received by individual grains. For these samples, the beta doses were modelled and adjusted accordingly. Ages for the 14 samples collected from MSA deposits post-dating the Howiesons Poort (HP) resulted in three age clusters, which are stratigraphically consistent with the three informally named cultural phases at Sibudu: namely, the post-HP, late MSA and final MSA. Weighted mean ages of 58.5 ± 1.4 ka, 47.7 ± 1.4 ka and 38.6 ± 1.9 ka were calculated for these phases, respectively. The three phases were separated by two occupational hiatuses with durations of 10.8 ± 1.3 ka and 9.1 ± 3.6 ka. We hypothesise that the punctuated presence of humans at Sibudu was determined by large-scale fluctuations in climate during oxygen isotope stage (OIS) 3, which resulted in alternating wet and dry periods. Phases of occupation correspond to wet periods when fresh water was available in the Tongati River, whereas intervals of site abandonment correspond to dry periods when people were forced to migrate in search of a reliable source of fresh water. Where people migrated to, remains unresolved.  相似文献   
43.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
44.
Thomas Hill Green (1836–82) has been widely recognized for his contributions to Liberal political‐social theory and for his Liberal partisanship. Historians and political theorists continue to emphasize his advocacy of limited state interference and democratic localism, as well as his anti‐imperialist statements. Recent scholars of English nationalism, national identity and patriotism, including Peter Mandler, Julia Stapleton, Krishan Kumar, H.S. Jones, Roberto Romani and Georgios Varouxakis, acknowledge Green as an acolyte of Giuseppe Mazzini, a Cobdenite and a Little Englander. While they place Green's ideas within a continuum of Victorian Liberal nationalist ideas (blending into Conservatism and socialism during the 20th century), their investigations foster the view that Green placed little value in the nation as a focus of individual and collective identification. In their readings of Green, the abstract ‘community’, free of national peculiarities, was to him the antidote to both individual and national narrowness. However, examination of Green's statements about community, the moral ideal and religion reveals that his theorising was informed by a view of national character different from that of most contemporary liberal intellectuals. Green rejected the ‘Liberal anglican’ view that a national church or clerisy was necessary to guide the development of the English nation. He identified ideas and practices of protestant dissenters as progressive forces in English history and endorsed them as means of national development. Religious pluralism and forms of ecclesiastical organisation promoting democratic localism were to Green among the essential characteristics of Englishness.  相似文献   
45.
This study uses data of about 9,000 apartment sales in Stockholm, Sweden, to assess the impact of crime on property prices. The study employs hedonic pricing modelling to estimate the impact of crime controlling for other factors (property and neighbourhood characteristics). Geographic Information System (GIS) is used to combine apartment sales by coordinates with offences, land use characteristics and demographic data of the population. The novelty of this research is threefold. First, it explores a set of land use attributes created by spatial techniques in GIS in combination with detailed geographical data in hedonic pricing modelling. Second, the effect of crime in neighbouring zones at one place can be measured by incorporating spatial lagged variables of offence rates into the model. Third, the study provides evidence of the impact of crime on housing prices in a capital city of a traditional welfare state, information otherwise lacking in the international literature. Our results indicate that apartment prices in a specific area are strongly affected by crime in its neighbouring zones, regardless of crime type. When offences were broken down by types, residential burglary, theft, vandalism, assault and robbery individually had a significant negative effect on property values. However, for residential burglary such an effect is not homogenous across space, and apartment prices in central areas are often less discounted by being exposed to crime than those in the city's outskirts.  相似文献   
46.
Satellite radio posed a new question for Canadian policy-makers: How to take advantage of a transnational radio service while ensuring cultural identity was not lost within channel offerings that are predominately American. Comparing the initial licensing of satellite radio in Canada (2005) to the merger of the services (2011) and the post-merger license renewal (2012) highlights a shift in the spatial understanding of satellite radio, from being determined by a satellite’s footprint to that of what I call ‘cultural lifelines,’ the various mobile devices and services that enable one to maintain connection to cultural content. Alongside shifting spatial considerations of satellite radio, Canadian content has increasingly been packaged as a brand or genre, catering to fragmented taste preferences and individual, mobile listening practices.  相似文献   
47.
The simulation of Sea-ice in a coarse resolution ocean general circulation model is examined in Hudson Bay and surrounding waters. Sea-ice distribution and duration compared well to climatological values, although ice thickness is undersimulated as it is in other modelling work. In Hudson Bay ice thickness variation was dominated by the atmospheric forcing as shown by the symmetric response of ice thickness to warming and cooling scenarios. Below ice heat fluxes play a more significant role in Foxe Basin and Baffin Bay where they mitigate air-ice heat loss by as much as 40 percent, thus limiting ice thickness and duration. Below ice heat flux reduces by 23 percent for the region of study (Hudson Bay, Foxe Basin, Baffin Bay, and Labrador Sea) for a global 3°C cooling and increases by 9 percent for a 3°C global warming. This asymmetric response is attributed to the ocean's asymmetric response to warming and cooling scenarios. In so much as Hudson Bay is dominated by atmospheric forcing rather than under ice heat as these results indicate, coarse resolution models may be useful in assessing the impact of change. However the necessary reconfiguration of the model grid render results from Foxe Basin and Hudson Strait less credible. On étudie la simulation de glace marine dans un modèle de circulation océanique générale à faible résolution dans la baie d'Hudson et dans les eaux avoisinantes. La distribution et la durée de la glace marine correspondent bien aux valeurs climatologiques, bien que l'épaisseur de la glace soit sous-simulée comme c'est le cas dans d'autres travaux de modélisation. Dans la baie d'Hudson, la variation de l'epaisseur de la glace est dominée par le forçage atmosphérique, comme on peut le voir d'après la réponse symétrique de l'épaisseur de la glace suivant les scénarios de réchauffement et de refroidissement. Les flux de chaleur sous la glace jouent un rôle plus important dans le bassin de Foxe et la baie Baffin, où ils permettent une réduction des pertes de chaleur air-glace allant jusqu'à 40 pour cent, limitant ainsi l'épaisseur de la glace et la durée. Le flux de chaleur sous la glace diminue de 23 pour cent dans la région étudiée (baie d'Hudson, bassin de Foxe, baie Baffin et mer du Labrador) pour un refroidissement global de 3C et augmente de 9 pour cent pour un réchauffement global de 3C. On attribue cette réponse asymétrique à la réponse asymétrique de l'océan aux scénarios de refroidissement et de réchauffement. Dans la mesure où, comme l'indiquent ces résultats, la baie d'Hudson est dominée par le forçage atmosphérique plutôt que par la chaleur sous la glace, des modèles à faible résolution peuvent être utiles pour évaluer l'impact des changements. Cependant, la reconfiguration nécessaire de la grille du modèle atténue la crédibilité des résultats obtenus dans le Bassin de Foxe et le détroit d'Hudson.  相似文献   
48.
A quantitative bioenvironmental study of cranioskeletal size has been made of a latitude-ordered sequence of 14 series of adult skeleton sets (N=305): the archaeological remains of aboriginal maritime peoples inhabiting the west coast of North America between southern California and the Arctic. Of eight osteometric parameters of cranioskeletal size developed, the most important are partial skeleton volume (PSK) and cranial capacity (CC); and the principal bone-affecting environmental factors are the northerly climate (CLIM2c), the reconstructed diet deficient in calcium and overabundant in animal foods and vitamin D (DIET3c), and demographic stress (DSg). Prior research has demonstrated that cranioskeletal size increases with geographical latitude and decreases under dietary calcioprivation and unphysiologically high birth rates. Upon linear multifactorial statistical analysis our main finding, limited to the Amerindian subsequence (n=11 series) from the Santa Barbara Channel, the San Francisco Bay Region and the Northwest Coast, is that PSK and CC vary in direct proportion to CLIM2c, and inversely with DIET3c and DSg. Controlling for the latter two osteoantitrophic factors, coastal Amerindian female PSK rises by 9% between 34 and 54°N latitude, CC by 5%; and the male incremental rates are somewhat higher, 13 and 10%, respectively. This newly discovered climate-dependent race cline, an example of Bergmann's Rule, is interpreted as factual evidence of a mid-Wisconsin or earlier arrival date for the first Palaeoindians. Cranioskeletal size of the very small (n=3 series) Western Eskimo subsequence approximates the northernmost values of the coastal Amerindian distribution. © 1998 John Wiley & Sons, Ltd.  相似文献   
49.
景德镇御窑遗址出土的15世纪中叶青花方胜纹绣墩,体量较大,器形特殊,出土时破损和缺失严重,修复难度较大。本研究通过分析传统考古修复中石膏作为补配材料的局限性,利用3D扫描打印的优势,设计采用新颖的高强度透明树脂取代传统修复补缺材料,并且结合特制的加固装置完成对大型青花绣墩的考古修复,满足了后期研究与展览的需要。本研究提出了具有一定实践意义的3D打印补配大件异形陶瓷器的修复技术路线。  相似文献   
50.
杜美龄  孙根年 《人文地理》2015,30(2):155-160
经济全球化背景下,国际"贸易-交通-旅游"(3T)互动日益增强。采用1982-2011年时间序列数据,分析国际贸易、交通和旅游总量的发展历程,从进、出口分量视角考察三者相关关系,运用最小二乘法构建回归方程。结果发现:①30年来国际贸易、交通和旅游的发展呈持续增长态势。国际贸易和旅游日益重要。②国际贸易、交通和旅游增长过程具有同步性,表现为波动周期同涨同落。③所构建的回归方程决断系数R2均在0.99以上,国际贸易、交通和旅游存在显著相关性。国际货运与国际贸易,国际客运与国际旅游之间具有确定、直接的因果关系;国际贸易与国际旅游的因果性尚待探究。  相似文献   
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