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1.
Between 1985 and 2007 overall nineteen human skulls dating to the Late Neolithic period were recovered at Kö?k Höyük, which lies within the borders of Bor, a district of the Ni?de Province in Central Anatolia. One of these skulls belongs to a child and the remainder to adult males and females. The plastered skulls may have been laid on or wrapped in mats and exposed either singly or in groups on a plaster surface inside the house. Among thirteen of these skulls the mouths, noses, eyes and ears were depicted with clay and painted with red ochre, while the remaining six were untreated. Two headless skeletons were also found in situ underneath the floor inside the house. One of these skeletons belongs to a child aged approximately 15–16 years old and the other belongs to an adult female. The modeled human skulls were encountered in the second and third cultural levels of the Late Neolithic period indicating that this characteristic mortuary practice lasted for quite a long time and likely disappeared by the Chalcolithic at Kö?k Höyük.  相似文献   
2.
The 12th-century depopulation of large villages in the Mimbres region of the US Southwest has been attributed to a number of causes, including resource stress. This study combines archaeological evidence and models of environmental conditions in the eastern Mimbres area of southwest New Mexico to assess the magnitude and timing of food stress from a combination of a period of reduced precipitation and the effects of prolonged hunting and farming activities on the landscape. Results indicate that large game in the area was quite sensitive to hunting pressure, and was locally depleted long before settlement reorganization occurred. Access to arable land was somewhat reduced around the time of settlement reorganization, but productive land remained locally plentiful. Although the settlement reorganization did not improve access to large game or arable land, farmers’ perceptions of below-average conditions for agriculture relative to their expectations and past experience would have contributed to decisions to move.  相似文献   
3.
The frequency content of ground motions seems to be one of the most important parameters to explain the structural damage experienced during worldwide strong earthquakes. The frequency content of ground motions can be characterized by various stochastic and/or deterministic indicators: the frequency bandwidth indicator ? (Cartwright & Longuet-Higgins) related to the power spectral density function and, respectively, the control (corner) period Tc of the structural response spectra or the mean period TM . Peak ground velocity (PGV) and the ratio PGA/PGV can be used as either damage potential parameters or frequency content indicators. A comparative analysis of stochastic and deterministic frequency content indicators and of PGV is applied to a set of 30 strong ground motion records having peak ground acceleration (PGA) from 0.2–0.8 g and recorded on 4 continents during the last 70 years.  相似文献   
4.
The assessment of human or economic losses due to single events (scenario) may effectively support decision makers in the development of important risk mitigation actions. The study presented herein sheds light on several problems and limitations in the current practice of scenario loss modeling, such as: the number of simulations required to achieve convergence; epistemic and aleatory uncertainty in the ground motion prediction and vulnerability models; and consideration of the earthquake rupture geometry. These issues are investigated using the Metropolitan Area of Lisbon (Portugal), and it has been observed that distinct assumptions in the loss modeling can lead to considerably different results. The findings of this study are also pertinent for probabilistic seismic risk analyses in which a large number of stochastically generated events are employed to assess probabilistic losses.  相似文献   
5.
Harvest experiments of wild crop relatives are essential for our understanding of the biology of wild plants embodied in the economy of ancient forager communities. Most of the previous experimental harvest reports spanned a single season and therefore are unable to address questions concerning long-term yield potential. Herein we report on six consecutive harvest seasons taking place at four sites in Israel that harbour wild pea populations: three typical Pisum fulvum sites and one typical Pisum elatius site. Three out of the four sites showed no indication of a decline in grain yield as a result of repeated harvest and the removal of a considerable portion of mature seeds. Site-specific factors seem to have a strong influence on the grain yield as no seasonal yield similarity was observed between adjacent and ecologically similar sites harbouring the same wild pea taxon. The erratic year-to-year wild pea yield we observed calls for a reassessment of the presumed role of grain legume species in Near Eastern hunter–gatherers' diet. Combined with published data on cultivation of wild pea, our results are inconsistent with models suggesting protracted domestication of Near Eastern grain legumes or with the preliminary attempts to apply Niche Construction Theory to the study of plant domestication in the Near East.  相似文献   
6.
张家志 《神州》2013,(13):57-57
本文运用ABAQUS软件对THG400卧式加工中心的立柱结构进行建模,无需用其他软件先建模后导入,节省了工作程序。同时在以后的网格划分等工作中更容易检查错误并及时修改。  相似文献   
7.
营城子汉墓位于辽宁省大连市甘井子区,是我国东北地区一处重要的大型汉墓群。营城子汉墓出土了一批玻璃耳珰,为探讨其成型工艺及来源,采用超景深显微系统进行了表面形貌观察,初步认为是模铸成型,并经过打磨。采用便携式X射线荧光光谱仪(XRF)进行了化学成分分析,结果显示,它们分属铅钡硅酸盐和钾硅酸盐玻璃系统,一件由Cu2+着色,其余主要由Co2+着色。其为我国自制,所用钴料来源相同,钴料的锰钴比特征与国产钴土矿的类似。并对营城子汉墓出土玻璃耳珰造型与化学成分体系间的关系进行了分析,对玻璃耳珰制作模式进行了初步探讨,进一步加深了对我国古代玻璃耳珰制作与传播的认识。  相似文献   
8.
This research advances a model for coastal-based dispersals into South Asia during oxygen isotope stage (OIS) 4. A series of GIS-based analyses are included that assess the potential for expansions into the interior of South Asia, and these results are compared with known archaeological signatures from that time period. The results suggest that modern Homo sapiens could have traversed both the interior and coastlines using a number of routes, and colonized South Asia relatively rapidly. Use of these routes also implies a scenario in which modern H. sapiens, by either increased population growth or competitive ability, may have replaced indigenous South Asian hominin populations.  相似文献   
9.
The work is aimed at the prediction of the cyclic response of bolted beam-to-column joints starting from the knowledge of their geometrical and mechanical properties. To this scope a mechanical model is developed within the framework of the component approach already codified by Eurocode 3 for monotonic loadings.

Accuracy of the developed mechanical model is investigated by means of the comparison between numerical and experimental results with reference to an experimental program carried out at Salerno University. The obtained results are encouraging about the possibility of extending the component approach to the prediction of the cyclic response of bolted connections.  相似文献   
10.
Probabilistic loss modeling can be used to develop risk reduction measures, such as the identification of regions more prone to human and economic losses, or to develop financial mechanisms to transfer the earthquake risk from local governments to the private sector. This study addresses several critical issues in probabilistic loss modeling, and provides recommendations depending on the intended final use of the risk results. Modeling issues related to convergence in probabilistic event-based analysis; consideration of epistemic uncertainties within a logic tree; generation of different types of loss exceedance curves; and derivation of risk maps are thoroughly investigated. The Metropolitan Area of Lisbon is used to explore these issues, and it is demonstrated that different assumptions in the loss modeling process can lead to considerably different risk results. Furthermore, the findings and recommendations of this study are also relevant for institutions that promote the assessment of earthquake hazard and risk, such as the Global Earthquake Model Foundation.  相似文献   
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