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31.
基底隔震已经大量应用于一般民用建筑中,被认为是在剧烈地震中保护建筑物最具发展前景的技术之一,但对于核电站这类特殊的建筑物应用较少,且研究比较薄弱。介绍了核电站水平及三维隔震装置的研发及性能测试,概述了核电站隔震系统抗震性能的研究进展和核电站隔震设计规范,指出了在核电站中应用隔震技术还有待解决的问题,对今后核电站隔震的研究提出了一些建议。  相似文献   
32.
The charm of the Isle of Wight, so much appreciated by visitors and the local population alike, is very much a combination of its delightful scenery and unique assemblage of vernacular buildings. These buildings range from isolated farmhouses to elaborate manor houses, castles and churches all constructed using the indigenous stone resources of the island. Today, these stone buildings, many of which date back to medieval times, are increasingly in need of conservation repair to maintain them for future generations. Essential to such conservation work is the safeguarding of the island's indigenous building stone sources as many of the stones used are unique to the island and no longer quarried. Protecting these stone sources could also provide stone for new building projects which would help to further enhance the character of the island's towns and villages.  相似文献   
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34.
This article explores how standards and codes for collaboration in international higher education influence the educational space of global online education and the way it functions within the context of international development aid. Firstly the article discusses the educational space of higher education and the geography of education whereby the aim is to situate global online education within the on-going discourse on standards in higher education, international development aid, and the knowledge economy. The article then examines a qualitative case study of an Internet-based masters programme attended by students from Europe and Africa. A main focus of the empirical analysis is the students’ experience of being geographically immobile while collaborating online internationally, including how this circumstance affected their motivation and participation and the benefits of the programme. In the concluding discussion it is argued that even though online collaboration among students and educational institutions is not entirely equal, common standards created a space in which positions were challenged and practices were changed over the course of online participation.  相似文献   
35.
Marine industries face a number of risks that necessitate careful analysis prior to making decisions on the siting of operations and facilities. An important emerging regulatory framework on environmental sustainability for business operations is the International Finance Corporation’s Performance Standard 6 (IFC PS6). Within PS6, identification of biodiversity significance is articulated through the concept of “Critical Habitat”, a definition developed by the IFC and detailed through criteria aligned with those that support internationally accepted biodiversity designations. No publicly available tools have been developed in either the marine or terrestrial realm to assess the likelihood of sites or operations being located within PS6-defined Critical Habitat. This paper presents a starting point towards filling this gap in the form of a preliminary global map that classifies more than 13 million km2 of marine and coastal areas of importance for biodiversity (protected areas, Key Biodiversity Areas [KBA], sea turtle nesting sites, cold- and warm-water corals, seamounts, seagrass beds, mangroves, saltmarshes, hydrothermal vents and cold seeps) based on their overlap with Critical Habitat criteria, as defined by IFC. In total, 5798×103 km2 (1.6%) of the analysis area (global ocean plus coastal land strip) were classed as Likely Critical Habitat, and 7526×103 km2 (2.1%) as Potential Critical Habitat; the remainder (96.3%) were Unclassified. The latter was primarily due to the paucity of biodiversity data in marine areas beyond national jurisdiction and/or in deep waters, and the comparatively fewer protected areas and KBAs in these regions. Globally, protected areas constituted 65.9% of the combined Likely and Potential Critical Habitat extent, and KBAs 29.3%, not accounting for the overlap between these two features. Relative Critical Habitat extent in Exclusive Economic Zones varied dramatically between countries. This work is likely to be of particular use for industries operating in the marine and coastal realms as an early screening aid prior to in situ Critical Habitat assessment; to financial institutions making investment decisions; and to those wishing to implement good practice policies relevant to biodiversity management. Supplementary material (available online) includes other global datasets considered, documentation and justification of biodiversity feature classification, detail of IFC PS6 criteria/scenarios, and coverage calculations.  相似文献   
36.
In shipping, safety depends on the reliability of the technical and human components of the ship-system, although the marine environment itself may sometimes be so hostile as to give rise to accidents that are beyond technical and human control. The need for a continuous analysis of shipping accidents is dictated by the accumulated evidence for the predominance of the human factor and the ever-increasing pressure for further improvement on the safety record of shipping. In this context, the effectiveness of enforced regulations towards the promotion of safety policy in shipping is assessed and the debate and focus on this issue are maintained.  相似文献   
37.
对山西应县木塔采用纳米复合纤维加固的建议   总被引:9,自引:0,他引:9  
山西应县木塔是古人留给我们的稀世珍宝,如何妥善地保护好这一珍贵的遗产,使之在加固时尽量保持原有的风貌,是一项复杂而艰巨的任务。根据长期的研究成果和实际工作的经验,提出了用纳米复合纤维加固应县木塔的建议,介绍了纳米复合纤维材料的特点,分析讨论了加固时的一些具体技术问题。  相似文献   
38.
简要介绍第二届国际地球岩石圈活动的地球物理监测研讨会的情况。会议于2005年9月12~16日在俄罗斯新西伯利亚市鄂毕河畔的科学城举行,来自6个国家的90多名代表参加了此次国际会议。会议的报告丰富多彩,科学家就地球岩石圈的地球物理活动监测研究进行了多方面的讨论,出版了6个专题的89篇研究论文。俄罗斯、中国、蒙古和哈萨克四国交界区的代表还就研究2003年9月27日发生的7.9级地震草拟了国际合作协议。  相似文献   
39.
Following a comprehensive review of the subject of man-made ground vibrations, measurements of ground vibration caused by vibratory sheetpile driving in recent soil deposits are reported in terms of particle velocities vs. distance from the source of vibration. The measurements were conducted on paved surfaces and sidewalks in the inner urban environment. Reconstructed particle displacement paths indicated, predominantly, vertical vibrations of the Rayleigh type. The attenuation rate of vibrations with distance was compared to published results of other studies and satisfactory agreement was found to exist. Values of particle velocity measured in this study, however, were lower than corresponding values of other studies under comparable values of rated vibratory kinetic energy. This is possibly due to different soil conditions. Average and upper bound linear log–log attenuation relationships are proposed, which fit the results of measurements and are representative of the conditions likely to be encountered in the urban environment. Measurement of vibrations on higher floors of multistory reinforced concrete buildings indicated a significant amplification of vertical vibration and an average curve for amplification magnitude vs. floor level was fitted to the results of measurements. A comparison of measured values of vibration with the observed performance of buildings and with damage threshold values suggested by existing codes and standards indicated that the latter do not provide safety against damage caused by vibratory densification of loose sandy soils. On the other hand, the existing criteria for human exposure to vibrations in buildings, according to the results of this study, seem to adequately define the degrees of human discomfort.  相似文献   
40.
重点介绍了高精度确定大型天线几何旋转中心的观测方案和计算方法。结合具体实例,在ITRF2000框架下,论述了控制网布设、观测方案确定、数学模型的建立、数据处理的过程,结果与已知外部参考结果进行了比较,坐标分量上达到毫米级外附精度,验证了观测、计算方案的可行性和准确性。  相似文献   
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