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1.
ABSTRACT This paper investigates the implication of production-technology uncertainty for the exclusion theorem. The paper presents the result that the risk-averse firm facing production technology uncertainty prefers an intermediate location to avoid risk under certain conditions. The firm chooses an intermediate location (over a corner location) particularly if its degree of risk aversion overwhelms the inherent convexity of profit with respect to location. The latter depends, in turn, on the structure of production technology characterized by the elasticity of substitution and returns to scale parameters.  相似文献   
2.
朱君杙 《世界历史》2015,(2):109-119,161
基督教会提倡"婚姻不可分解"的理念,这种理念随着基督教会势力的壮大和宗教思想的深入人心,对中世纪西欧封建帝王的婚姻构成了一种道德约束作用。而罗马教延等现实政治生活中的各方势力也常常以此为由,向那些有违婚姻道德的世俗帝王问责发难。洛林吉亚王国的国王罗退尔二世的离婚案即是一起因此而发的政治风波。由于基督教婚姻理念的约束作用,加洛林帝国的分裂瓦解、同宗诸王的纷争内斗、教皇权威开始抬头等众多历史因素的叠加、交织,使得罗退尔二世不仅无法像他的先祖查理曼那样可以自由地离异,反而成了众矢之的,最后以"身死国灭"的历史悲剧黯然收场。  相似文献   
3.
Traditions and transitions in Korean bronze technology   总被引:1,自引:0,他引:1  
Metallurgical examination of Korean bronze artifacts shows that a technical tradition based on casting and use of leaded high-tin alloys was established in Korea at the early stages of bronze use. After the subsequent discovery of quenching methods that suppress formation of the brittle δ phase, new thermo-mechanical techniques were introduced between the 7th and 10th centuries AD. Lead-free alloys were used, and tin contents near that of the peritectic point in the Cu–Sn phase diagram were chosen. Leaded high tin alloys continued in use, but only in cast objects, and with significant composition variation. The unique conditions during the time of innovation suggest that the transition to new metallurgical techniques was gradually achieved through domestic technical innovation inspired by external influences.  相似文献   
4.
Metallurgical study of seven cast iron artifacts recovered from sites of the former Xiongnu (BC 3rd to AD 1st), Turk (AD 6th to 8th), Khitan (AD 10th to 12th), and Mongolian empires (AD 12th to 15th) shows that the earlier Xiongnu and Turk artifacts were made of cast iron alloys of near eutectic composition. The later Khitan and Mongol objects had greatly reduced carbon content in the range of ultrahigh carbon steel rather than cast iron, and contained more than 0.5 mass % silicon as an alloying element. Inclusions high in sulfur, phosphorus or silicon are also present. These differences suggest that Mongolia experienced a technical transition a few centuries before the establishment of the Mongolian empire, which is in agreement with some written accounts. The microstructures of the cast iron artifacts are compared with the related archaeological and documentary evidence. The results suggest that the use of fossil coal in smelting and the state policy of controlling iron production were the major factors responsible for the transition.  相似文献   
5.
魏晋南北朝玉佩研究   总被引:1,自引:0,他引:1  
魏晋南北朝玉佩自发现以来,学术界对其性质和组构样式的判断皆不甚明了。近年南京仙鹤观东晋玉佩的完整发现,为研究其结构与性质提供了详实的研究资料。本文以此为基础,结合国内各地玉佩的发现情况及历史文献资料,分析魏晋南北朝时期玉佩发展、演变的历史原因,并试对玉佩构件进行了初步的复原研究。  相似文献   
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7.
南京明代宝船厂遗址的发掘及船舶构件的出土,为研究郑和下西洋活动,尤其是郑和船队的相关信息提供了宝贵的资料。宝船厂遗址中出土的舵杆是船舵的重要组成部分,也是复原船舵的主要依据。通过对舵杆本体特征部位与古代不平衡舵的比较研究,对舵首、舵身、舵尾特征部位的结构、功能进行了深入、细致的分析研究,初步完成了船舵的结构、功能和操控系统的复原。  相似文献   
8.
From AD 1274 Chinese emperor Kublai Khan dispatched fleets of ships in a series of attempts to expand the empire's hegemony and extend his rule into East Asia (Japan) and Southeast Asia (Vietnam, Champa and Java). Archaeological remains associated with the fleets and battles have been found at Takashima Island, Japan and on the B?ch Ð?ng River, Vietnam. This paper develops a thematic approach to these sites within a framework of naval battlefield archaeology. It compares the similarities and differences in environmental conditions and archaeological contexts of the two sites in Japan and Vietnam. It also outlines recent archaeological research conducted between 2008 and 2010 on the physical remains at the B?ch Ð?ng River battlefield site.  相似文献   
9.
In this article, a collaborative structure analysis (CSA) system is developed for integrating different finite-element simulation programs. In this system, a simulated structure is divided into multiple substructures, and the interaction between the substructures is considered. Interfaces for the commercial finite-element program ABAQUS and for an open-source framework for structure analysis, OpenSees, are developed to achieve CSA integration. The CSA system is applied to analysis of a soil-structure interaction (SSI) problem, and the effects of SSI are investigated, and the efficiency and accuracy of the system are demonstrated.  相似文献   
10.
建设博物馆数字化的科普平台,加强了对馆藏文物的保护能力,促进了博物馆的历史文化教育和传播功能,具有重大的现实意义和深远的历史意义。本工作将介绍其构建方法:采用全景拍摄、三维扫描等数字化信息采集技术,对博物馆建筑的内外景、重点馆藏文物进行信息采集,构建虚拟的历史遗迹遗存、网上博物馆,将实体博物馆以数字化方式完整呈现,通过互联网/移动互联网提供身临其境的虚拟参观服务;采用二维码、电子标签、混合定位等技术,为现场观众提供自助音视频文化科普导览服务;策划制作面向广大青少年的反映中国历史文化遗产的4D影视科普作品及建设面向普通观众开放的博物馆4D动感影厅工程播放系统,以此构建博物馆数字化科普平台。  相似文献   
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