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先秦中国和古代希腊文明起源的地理环境之比较 总被引:3,自引:0,他引:3
文明起源的地理环境可以分为整体地理环境和中心地理环境。前者指文明整体能力所及的极限地理范围,后者指文明主体的主要活动区域。从这两个角度分别进行比较,将有助于解释希腊和中国文明侧重于陆地或是海洋发展的原因。 相似文献
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This paper presents material characteristics and raw material provenance of the stone moulds for bronze slender daggers from Galdong. This type of bronze dagger is uniquely distributed in the Korean Peninsula and these stone moulds were the first to be found by excavation. The stone moulds were made of igneous hornblendite with course-grained holocrystalline textures. Based on petrological, mineralogical and geochemical characteristics, the original rock materials of the moulds were inferred to be derived from the Jangsu or Namwon areas which are about 50 km away from the excavation site. It is a notable achievement that this provenance study confirmed the domestic production of Korean-styled daggers. 相似文献
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Social differentiation is characterized by differences in social status and wealth, which are established and maintained by controlling and constraining the labour and flow of resources. This would affect the development of various aspects of a settlement in establishing hierarchical relationships. This study focuses on identifying the variations in the distribution of certain resources, such as imported goods, that help interpret the social meaning, particularly with regard to social status and wealth, of house structures having different shapes in an ethnic settlement in Taiwan. A petrographic study and residue analysis of the pottery along with spatial examination of the material remains were conducted to achieve the goal. 相似文献
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JAMES D. LEE SIYUAN SHEN MAJID T. MANZARI YIN-LIN SHEN 《Journal of Earthquake Engineering》2013,17(1):67-96
The dynamic finite element equations of a two-dimensional structure made of axial-flexural frame elements with tendon-driven actuators have been derived. A critical review of classical optimal control theory is made with respect to its application to the control of structure under seismic excitations. Seven control algorithms, including two newly proposed algorithms, have been described, investigated and discussed. The need of an optimal observer, Kalman filter, is discussed. The validity of separation theorem applicable to the optimal stochastic control of structure for earthquake resistance is shown. How the control system perform under the circumstances of actuator saturation is also shown. Several numerical examples are worked out to demonstrate and compare the efficiency and limitations of those control algorithms. 相似文献
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The Anticosti Basin is a large Paleozoic basin in eastern Canada where potential source and reservoir rocks have been identified but no economic hydrocarbon reservoirs have been found. Potential source rocks of the Upper Ordovician Macasty Formation overlie carbonates of the Middle Ordovician Mingan Formation, which are underlain by dolostones of the Lower Ordovician Romaine Formation. These carbonates have been subjected to dissolution and dolomitization and are potential hydrocarbon reservoirs. Numerical simulations of fluid‐overpressure development related to sediment compaction and hydrocarbon generation were carried out to investigate whether hydrocarbons generated in the Macasty Formation could migrate downward into the underlying Mingan and Romaine formations. The modeling results indicate that, in the central part of the basin, maximum fluid overpressures developed above the Macasty Formation due to rapid sedimentation. This overpressured core dissipated gradually with time, but the overpressure pattern (i.e. maximum overpressure above source rock) was maintained during the generation of oil and gas. The downward impelling force associated with fluid‐overpressure gradients in the central part of the basin was stronger than the buoyancy force for oil, whereas the buoyancy force for gas and for oil generated in the later stage of the basin is stronger than the overpressure‐related force. Based on these results, it is proposed that oil generated from the Macasty Formation in the central part of the basin first moved downward into the Mingan and Romaine formations, and then migrated laterally up‐dip toward the basin margin, whereas gas throughout the basin and oil generated in the northern part of the basin generally moved upward. Consequently, gas reservoirs are predicted to occur in the upper part of the basin, whereas oil reservoirs are more likely to be found in the strata below the source rocks. Geofluids (2010) 10 , 334–350 相似文献
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