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排序方式: 共有606条查询结果,搜索用时 15 毫秒
481.
482.
薄膜试片测试法是一种能够全面有效地对博物馆藏展材料进行评估筛选的测试方法,对其腐蚀现象进行图象采集及进行数据化分析能够得到更为客观准确的测试结果.本工作对应该测试法设计了专门图像采集的硬件装置,采用密闭光源和彩色工业摄像机,可以得到清晰的试片图像.软件系统将采集图像、打开原始图像、图像分割处理、材料分级评价等功能模块化,并根据具体功能设计实现了基本应用的可视化界面.实验表明,该系统能够快速、准确地对藏展材料对试片的腐蚀现象进行数据化分析,使藏展材料的评估分级由人工目测走向计算机视觉计算,具有快速、客观、误差小等特点. 相似文献
483.
Oddy测试法是一种最为常用的评估材料是否适合博物馆文物储藏与展示的测试方法,其缺点在于采用活性低的块状金属试片,需要28天的测试周期,同时试片表面平整度以及人为主观因素会影响目测结果的准确性.本工作制备了银纳米薄膜试片替代Oddy测试法中块状金属试片,以半径10mm玻璃圆片为基质,银薄膜厚度约为200~220nm.实验结果表明,采用银纳米薄膜试片后,腐蚀现象在14d后可充分显现并分化,延长至28d时腐蚀现象基本无大变化,有效的缩短了测试周期.同时尝试结合数码图像采集技术,有利于进一步的腐蚀现象数据化分析研究工作,从而得到更加客观准确的测试结果. 相似文献
484.
为全面了解武汉博物馆的文物保存环境现状,科学评价该馆文物库房环境达标试点工程的成效,总结实践经验,服务我国馆藏文物保存环境改善工作,采用相关检测设施和仪器分析手段,针对该馆的改造新文物库房、未改造老库房、文物储藏柜、包装囊盒、陈列展厅、文物展柜内的环境质量,检测了其中的温度、相对湿度、甲醛浓度、板材的木材含水率、可见光照度以及紫外辐照强度等指标,并对环境中的酸性气体和VOC浓度进行了采样分析。检测研究结果表明,武汉博物馆达标改造工程对库房温湿度和光照水平的控制成效明显,基本达到了文物保护要求;增添使用的文物储藏柜、包装囊盒、活性炭吸附材料等具有一定的微环境调控效果。由于装饰材料和橱柜材料等散发污染物的影响、恒温恒湿系统的间歇式运转模式、部分老库房和展厅采用无防护自然采光设计等原因,现文物保存环境中还存在主要污染气体浓度普遍偏高、湿度呈现短周期性波动、局部光照水平偏高等情况。对此,给出了一些建议。 相似文献
485.
影响旅游英语教学质量诸因素的思考与对策 总被引:8,自引:0,他引:8
本文着力分析了影响旅游英语教学质量的因素,提出提高旅游教学质量的构想. 相似文献
486.
John P. Cooper Andrew Wetherelt Chiara Zazzaro Matthew Eyre 《International Journal of Nautical Archaeology》2018,47(2):419-442
This article presents the results of a project to 3D laser scan and digitally model 14 watercraft from the Qatar Museums collection, comprising a range of regional vessels: most had not been surveyed previously. The project used the resulting point clouds generated 2D naval lines and orthographic records of the vessels in their current condition, and photorealistic 3D digital models for gallery display. This case study provides illustrative examples of the intermediate stages and final outputs. It assesses the pros and cons of 3D laser scanning as a survey technology for nautical scholars in terms of the time, cost, and skillset, as well as logistical considerations. It also compares the accuracy of traditional hand survey methods. 相似文献
487.
《Conservation and Management of Archaeological Sites》2013,15(1-4):60-71
AbstractIncreasingly, developers and archaeologists search for ways to build on archaeological sites, while at the same time preserving the remains underneath. However, deciding which effects of construction on archaeological sites are acceptable and which are not is hampered by the lack of knowledge on the impacts of construction on archaeological sites. This paper provides an update on some of the effects of building on archaeological sites. Recent research had shown that displacement piles cause less disturbance in soft soils than previously thought. Moreover, replacement piles may be less benign that assumed up till now. Effects of loading on archaeological sites are described, and gaps in the knowledge on these effects are indicated. More research is needed in this field, especially on predicting soil disturbance and damage to weak materials. Impermeable surfaces and constructions on top of sites may affect the visibility of soil features due to decreased rainwater infiltration. Finally, a series of non-physical effects are mentioned that will have to be taken into account when deciding on allowing building on archaeological sites. 相似文献
488.
AbstractIn the 25 years since the dissolution of the Soviet Union, sweeping political, economic, and social changes have profoundly influenced environmental protection in Russia, the world’s largest country and one of global importance with respect to natural resources, biodiversity conservation, wilderness preservation, and climate change mitigation. This paper reviews the state of the environment by assessing post-Soviet era changes to legislation, government regulatory institutions, and civil society. A gulf exists between Russia’s formal environmental laws and state agency capacity and interest in enforcing them. This stems, in part, from repeated bureaucratic reorganizations that have progressively eroded environmental institutions. The Russian environmental movement, which blossomed during Gorbachev’s reforms in the late 1980s, struggled in the 1990s to mobilize the broader public due to economic hardship and political instability. Since then, the Putin administration has labeled many environmental groups “anti-Russian” and used aggressive tactics such as raiding NGO offices, intimidating journalists, and instituting severe legislative measures to quash advocacy and dissent. Post-Soviet environmental successes have been relatively few, with expansion of the protected area system and forest certification notable exceptions. These successes can partially be attributed to efforts by large environmental organizations, but expansion of certification and corporate social responsibility is also tied to Russian business interests dependent on natural resource export to global markets increasingly sensitive to environmental concerns. The paper concludes by illustrating how corruption, poor enforcement, and the muzzling of civil society render the state incapable of resolving arguably its most significant environmental challenge: illegal and unregulated resource use. 相似文献
489.
本文分析了近90年来160多种中国考古文物类期刊的创办与发展情况,提出中国考古文物类期刊的发展与中国考古学学科的发展一样,经历了初创与早期发展、全面发展、复苏时期、成熟发展等四个阶段。现在的中国考古文物类期刊的格局,是1979年以来形成的。目前主要刊物的栏目形式有所变化.但研究论文与田野资料并重的办刊方针总体上没有变化。近10年来一些刊物新增加了文化遗产保护、科技考古、公众考古的内容,这应是中国考古学在21世纪发展的三项新的内容。 相似文献
490.
Víctor Manuel Velzquez Durn Rocío Rosales Ortega 《Tijdschrift voor economische en sociale geografie = Journal of economic and social geography = Revue de géographie économique et humaine = Zeitschrift für ?konomische und soziale Geographie = Revista de geografía económica y social》2017,108(5):625-640
This paper examines the governance of local productive systems by articulating two fundamental concepts from geographical institutionalism: path dependency and contingency. We identify internal and external contingencies that have significantly impacted the development trajectory of pyrotechnic production in Tultepec, Mexico, giving rise to governance dynamics characterised by a lack of co‐ordination among local producer associations. Consequently, the main local institutional arrangements are controlled by particular interest groups. This limits the participation of local actors in defining national regulations relating to pyrotechnic production, resulting in a vertical/centralised law mainly defined by the state. We argue that improving the governance of the pyrotechnic productive system in Tultepec requires the co‐ordination of private and public actors at different territorial scales, in order to build up an inclusive regulatory framework which can take into consideration the diversity of local producers. 相似文献