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41.
This paper describes the numerical simulation of the seismic behaviour of a mock-up of a six-floor building, constituted by two parallel R/C walls and experimentally tested on a shaking table. Within the scope of an international benchmark the mock-up was submitted to three earthquakes with intensities up to 0.71 g, which induced nonlinear behaviour in the concrete and reinforcement. For the numerical simulations concrete is discretised with 2D finite elements, and its behaviour reproduced via a constitutive model with two scalar damage variables. Steel rebars are discretised with 2-noded truss elements, and their constitutive behaviour under cyclic conditions reproduced by the Menegottb-Pinto model. Specific attention is devoted to Rayleigh damping, focusing on two different strategies: (i) disregarding the damping contribution, or (ii) adopting a damping matrix that takes into account the stiffness changes during the nonlinear analyses. Main results and strategies for simulating the benchmark axe presented, with emphasis on the comparison between the numerical and the experimental results, which show good agreement when the damping contribution is neglected.  相似文献   
42.
产业转型期的长三角区域海洋旅游特色产品链构建   总被引:1,自引:0,他引:1  
马丽卿  胡卫伟 《人文地理》2009,24(2):125-128
长三角地区是我国综合实力最强的经济中心,这一地区海岸线漫长,海洋旅游资源丰富,具备了发展旅游的资源、需求、区位和产品四大优势,是重要的旅游目的地和旅游客源地。近年来,长三角地区的入境旅游增长幅度逐年下降,旅游经济在国民经济体系、对外经济体系和服务经济体系中的比重也正发生着变化,旅游业面临着转型。作为现代服务业的旅游业是无边界产业,它与其它行业的广泛融合、相互渗透,形成了多样化的产业新形态。本文剖析了长三角地区转型时期的旅游产业,分析该区域旅游产业的新形态,并提出了构建海洋特色旅游产品链的设想。  相似文献   
43.
罗海明  甄峰 《人文地理》2005,20(4):9-14
本文运用中国大都市区界定指标体系,根据2002年数据对长江三角洲大都市区进行了重新划分。从划分的结果看,后者与前者相比发生较大变化。而中国大都市区界定指标体系对这种变化表现出了一定的不适应性,因此本文试图通过中美大都市区界定指标体系的比较研究为中国大都市区界定指标体系的修订提供参考。  相似文献   
44.
C地点共清理墓葬37座,为圆角长方形土坑竖穴墓,多数墓葬为单人仰身直肢葬。随葬品主要是陶器,器物组合以筒形罐和壶为主,还出土石器、骨器、玉器等。C地点墓葬的文化内涵与此前发掘的A、B两地点新石器时代墓葬应属同一种文化,可暂称为南宝力皋吐类型。  相似文献   
45.
46.
The Levant of the fourth millennium B.C. was scattered with numerous small farming communities. The agricultural activities were based on growing barley, wheat, lentils, and fruit trees. This was accompanied by raising sheep-goats, pigs, and cattle and occasionally using marine resources. The architecture and the thick accumulation of debris loaded with pottery refuse indicate that the sites were sedentary and occupied for long periods. The social organization of these communities does not seem to have been very complex. The evidence argues against the existence of hierarchies and high-status social units that had the power to dominate and permanently regulate production and distribution. The evidence of religious activities also indicates that a priesthood, if it existed, was not dominant in the regulation of social and economic activities. The rapid cultural changes in the Levant during the late fourth and early third millennium were probably caused by the impact of the events in Egypt and Mesopotamia. The local modifications were readjustments to the large-scale changes in the Near East which influenced the rural and provincial Levantine Chalcolithic societies.  相似文献   
47.
尺度重组理论视角下的粤港澳大湾区建设研究   总被引:2,自引:0,他引:2  
粤港澳大湾区建设是由中央政府推行的新的区域发展政策安排,旨在调控国家、区域和城市尺度之间的关系进而引导资本流动以实现特定的空间发展目标,因此可视之为新一轮国家的尺度重组。借鉴西方的尺度重组理论,本文主要从大珠三角城市在经济上的空间联系以及香港问题在政治上的领域关系等两个方面,探讨关系空间如何影响到国家的尺度重组,以及国家的尺度重组对城市的尺度重组的影响。研究认为,粤港澳大湾区建设在于重塑资本流动的地方空间,为“资本固着”提供社会活动平台,继续参与国际劳动分工,深化经济合作,提高区域的全球竞争力。与此同时,国家也通过尺度重组来解决经济全球化过程中出现的领域政治问题,通过新的空间规划把边界问题纳入一体化的经济发展体系之下,保证政治稳定。中央政府把国家建设的尺度下移到粤港澳地区,促进了粤港澳的城市发生多元尺度重组策略,包括城市内部的尺度上推和尺度下移,城市外部的合作联盟和尺度政治。最后,文章从区域发展的角度分析粤港澳大湾区建设带来的影响,讨论粤港澳大湾区的建设与实践对尺度重组理论的补充和对认识国家政治经济发展的启示意义。  相似文献   
48.
In this study we applied a multidisciplinary approach, coupling geophysical and geochemical measurements, to unveil the provenance of 170 obsidian flakes, collected on the volcanic island of Ustica (Sicily). On this island there are some prehistoric settlements dated from the Neolithic to the Middle Bronze Age. Despite not having geological outcrops of obsidian rocks, the countryside of Ustica is rich in fragments of this volcanic glass, imported from other source areas. The study of obsidian findings was carried out first through visual observations and density measurements. At least two different obsidian families have been distinguished, probably imported from Lipari and Pantelleria islands. Analysing the magnetic properties of the samples, these two main sources were confirmed, but the possibility of other provenances was inferred. Finally, we characterized the geochemical signature of the Ustica obsidians by performing microchemical analyses through electron microprobe (EMPA) and laser ablation (LA–ICP–MS). The results were compared with literature data, confirming the presence of the Lipari and Pantelleria sources (Sicily) and indicating for the first time in this part of Italy a third provenance from Palmarola island (Latium). Our results shed new light on the commercial exchanges in the peri‐Tyrrhenian area during the prehistoric age.  相似文献   
49.
During the late Longshan period (ca. 4200–3900 BP) settlements on the Central Plains of China underwent a diversification in food production technologies, which set the stage for rapid economic and social development. The introduction of novel domesticates such as rice, wheat, cattle, and sheep not only provided more food choices, but also changed ideas concerning land use, farming techniques, and the use and mobilization of large scale labor forces. To better understand the contribution that these new dietary items and practices made to shaping the late Longshan period societies, a stable isotope ratio study of humans (n = 12) and animals (n = 42) was conducted at the late Longshan period site of Wadian. The human δ13C and δ15N values are clustered into two distinct groups. One group of nine individuals (δ13C = −9.9 ± 0.7‰; δ15N = 7.5 ± 0.5‰) had a predominately C4 diet based on millet grains with little protein input from the domestic animals. The other group of three individuals (δ13C = −14.3 ± 0.8‰; δ15N = 10.2 ± 0.3‰) had a mixed C3/C4 diet of millets and rice and were consuming sheep and cattle. The animals also displayed dietary diversity with the pigs (δ13C = −11.3 ± 2.5‰; δ15N = 6.9 ± 1.0‰, n = 10) and dogs (δ13C = −10.1 ± 1.0‰; δ15N = 7.2 ± 1.1‰, n = 7) having mostly a C4 plant based diet (millets). In contrast, the cattle (δ13C = −12.8 ± 2.1‰; δ15N = 7.6 ± 0.7‰, n = 9), sheep (δ13C = −16.7 ± 0.9‰; δ15N = 7.6 ± 0.1‰, n = 2), and cervids (δ13C = −20.8 ± 0.9‰; δ15N = 5.0 ± 1.2‰, n = 10) had diets with a greater contribution from C3 sources such as rice and wild plants. The discovery that humans and animals had different subsistence patterns indicates dietary complexity at Wadian and that rice agriculture, and cattle and sheep husbandry practices were already an important part of the local economy by the late Longshan period in the southern region of the Central Plains of China. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
50.
This article explores the living conditions and specifically the possible etiologies of subperiosteal reactions among those seafarers who did not survive Christopher Columbus' second voyage to the Americas and died at La Isabela, the first permanent European settlement in the New World, which is located in the present‐day Dominican Republic. The town was founded in 1494 by Christopher Columbus (1451–1506) and occupied for only 4 years. This study analyses the macroscopic and histological evidence of the skeletal series excavated from this contact cemetery, which is presently curated at the Museo del Hombre Dominicano. Twenty of the 27 systematically scored individuals reveal subperiosteal bone accretions, and in at least 15 individuals, these accretions appear bilaterally. The morphology, distribution and healing stages of the majority of these lesions provide new, direct evidence suggesting severe adult scurvy, a condition caused by sustained vitamin C deprivation, which was common among seafarers before the 18th century. The historical context surrounding the individuals' death at the European contact settlement and the conditions and duration of Christopher Columbus' second transatlantic voyage to the New World represent key elements in the interpretation of these lesions. In this case, the evidence also corroborates the known failure of Columbus' crew to exploit the locally available foods rich in vitamin C. Scurvy probably contributed significantly to the outbreak of sickness and collective death within the first months of La Isabela's settlement, an aspect that inflects the current discussion about the degree of virulence of New World infections that decimated the European newcomers, who we conclude to have been already debilitated and exhausted by scurvy and general malnutrition. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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