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71.
石质文物破坏问题不仅在于人为破坏和表面污染,更多来自自然因素对文物的破坏,例如,日晒雨淋、风沙吹蚀、地表水的冲刷、地震、地下水的侵蚀溶蚀。为对第六批全国重点文物保护单位阳华岩摩崖石刻露天石质文物病害进行探查,采用无损探测的地面核磁共振方法和探地雷达方法,直接找水的地面核磁共振方法成功探测出摩崖石刻依附岩体地层含水分布状况。探地雷达方法探测出依附岩山体内岩溶、裂隙的发育状况。两种方法探测结果发现,石刻依附岩体内岩溶、裂隙发育,部分区域岩溶裂隙带已成为地下水汇聚场所或流通通道,对阳华岩摩崖石刻构成了极为严峻的侵蚀威胁。两种方法解释结果互为验证,研究结果为阳华岩摩崖石刻的病害治理和保护提供了宝贵的基础资料。 相似文献
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Riitta Rainio Antti Lahelma Tiina Äikäs Kai Lassfolk Jari Okkonen 《Journal of Archaeological Method and Theory》2018,25(2):453-474
In northern Finland, near the canyon lakes of Julma-Ölkky, Somerjärvi, and Rotkojärvi, steep rock cliffs produce distinctive acoustic spaces. On these cliffs, prehistoric rock paintings (5200 to 1000 BC) as well as an ancient Sámi offering site (circa 1100 to present) can be found. Ethnographic sources describe that the Sámi used to sing and listen to echoes while making offerings there. This article presents the results of an archaeoacoustic research project that seeks to explore the role of sound in the development and use of these archaeological sites. The innovative set of methods includes multichannel impulse response recording, angle-of-arrival estimation of early reflections, spectrum analysis, digital image processing, and 3D laser scanning. On the basis of the analyses, it is concluded that the cliffs that have been painted or held as sacred are efficient sound reflectors. They create discrete echoes and, accordingly, phantom sound sources. Especially at the Värikallio cliff near Lake Somerjärvi, the sound appears to emanate directly from the painted figures. These results, together with previously unnoticed drumming figures in the Värikallio painting, provide a clue to the significance of the sound rituals at these sacred sites. 相似文献
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Jonathan Z. Liang Hong Hao Ying Wang Kai Ming Bi 《Journal of Earthquake Engineering》2013,17(7):997-1028
Perth is the largest city in Western Australia and home to three-quarters of the state's residents. In recent decades, there have been a lot of earthquake activities just east of Perth in an area known as the South-West Seismic Zone. Previous numerical results of site response analyses based on limited available geology information for PMA indicated that Perth Basin might amplify the bedrock motion by more than 10 times at some frequencies and at some sites. Hence, more detailed studies on site characterization and amplification are necessary. The microtremor method using spatial autocorrelation (SPAC) processing is a useful tool for gaining thickness and shear wave velocity (SWV) of sediments and has been adopted in many previous studies. In this study, the response spectrum of rock site corresponding to the 475-year return period for PMA is defined according to the probabilistic seismic hazard analysis (PSHA) based on the latest ground motion attenuation model of Southwest Western Australia. Site characterization in PMA is performed using two microtremor measurements, namely SPAC technique and H/V method. The clonal selection algorithm (CSA) is introduced to perform direct inversion of SPAC curves to determine the soil profiles of representative PMA sites investigated in this study. Using the simulated bedrock motion as input, the responses of the soil sites are estimated using numerical method based on the shear-wave velocity vs. depth profiles determined from the SPAC technique. The response spectrum of the earthquake ground motion on surface of each site is derived from the numerical results of the site response analysis, and compared with the respective design spectrum defined in the Australian Earthquake Loading Code. The comparison shows that the code spectra are conservative in the short period range, but may slightly underestimate the response spectrum at some long period range. 相似文献
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杭州萧山老虎洞东周遗址出土两件青铜工具,工具出土时已碎裂为数段,锈蚀状态严重。针对两件青铜工具的研究,主要从微观领域来探讨青铜工具的工艺技术及腐蚀特点,并通过建立电化学反应模型,运用电极电位差的理论,来试析电极电位对金相组织腐蚀的影响。同时提出在青铜修复时,可利用电极电位的原理来补配修复材料,以达到文物保护的目的。 相似文献
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会展产业的经济效应是会展研究领域的重要论题.本文在已有研究提出的理论模型的基础之上,从创业资源的需求和供给两方面,分别选取3家典型的创业企业作为需求方和1家会展企业作为供给方开展多案例研究并进行比较分析,验证得出基于创业资源的会展经济效应作用机制,并进一步揭示在这一作用过程中各种创业资源之间的互动关系.研究发现:会展活动在一定时间空间内集聚资源而产生供给,创业企业在开发创业机会的过程中受到高度的资源约束而产生需求,这种供需关系使得资源成为会展活动实现经济效应的传导手段,创业企业从会展活动中获得社会资源、技术资源、财务资源、组织资源、人力资源、物质资源等创业资源,其中社会资源和人力资源发挥了杠杆作用. 相似文献
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