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1.
王勇  朱雅琴 《人文地理》2020,35(6):76-84
江南水乡古镇是江南地域社会经济活动的高度聚合体,而空间作为功能的载体,是古镇保护与发展中的关键一环.本文以周庄古镇为例,从行动者网络理论视角切入,解析不同旅游发展阶段古镇空间演化的行动者作用路径.研究发现,关键行动者意图、行动者网络结构的变化,推动了周庄古镇空间重构和演化.在观光旅游发展阶段,周庄镇政府为关键行动者,通...  相似文献   

2.
通过分析圣路易华人社区的发展与演变,提出了美国华人社区研究的新观点——“文化社区理论”。圣路易华人“文化社区”不同于传统的唐人街,也不同于当代美国东西海岸许多地区以商业利益而形成的新型郊区唐人街,它是由于中华文化凝聚力而产生的社区;华人聚集一堂,不仅是为了经商贸易,而更多是为了弘扬中华文化。文化社区现象标志着少数族裔在美国社会政治与经济地位的上升。  相似文献   

3.
一种饱水木质文物含水率无损检测方法的研究   总被引:1,自引:0,他引:1  
含水率是评估饱水木质文物糟朽程度最常用的物理参数之一。目前含水率检测常用方法有烘干法、电阻法、近红外光谱法等,但这些方法或属于破坏性分析,或检测范围不适用。为寻找一种适用于饱水木质文物含水率的无损检测方法,基于饱水木材组成理论模型,建立了含水率与湿态密度、灰分含量三者之间关系,进而提出一种检测含水率的便捷方法——溶液密度法。采用上述方法对天长、淮北等地出土饱水木质样品含水率进行测试,并与烘干法测得标准值进行验证。结果发现两者数据较为接近,相对误差在10%以内,证明了该方法的可靠性。进一步研究发现,样品越糟朽,使用该方法获取的数据与标准值之间相对误差越小。说明该方法更适用于糟朽饱水木材含水率的检测。  相似文献   

4.
本文就边界研究中的一系列重大问题,诸如边界概念、边界研究的内容和特点、边界研究中必须注意区别的几种关系、边界变化的规律、边界研究的条件和意义,以及我国过去边界问题研究的教训等,逐一进行了理性的思考,并在这种理性思考的过程中,根据新时期的新形势和我国政府提出的新安全观、国际观与睦邻友好的外交政策,提出边界是建立睦邻友好国家关系的纽带和桥梁的论点,进而提出边界学概念。期望能对我国边界理论的建设和边界问题研究事业的进展有所助益。  相似文献   

5.
    
In this paper we consider the prehistory of quantum gravity (1916–1930) from two perspectives. First, we investigate how this research field constituted itself and we propose for the first time a red thread to trace its evolution in this earliest period. Second, we focus on a case study: the earliest work of Léon Rosenfeld. In 1927 he tried to merge wave mechanics with general relativity in the context of a five‐dimensional universe. We describe how Oskar Klein, Louis de Broglie, and Théophile De Donder influenced Rosenfeld's work and analyze how and why Rosenfeld attempted to reconcile Einstein's theory with quantum phenomena. We argue that Rosenfeld investigated for the first time the corrections to a classical space‐time metric generated by a quantum source. As far as we know, Rosenfeld's approach has been largely ignored until today: he himself considered it “an accident.” After having reconsidered its connection with de Broglie's ideas and Rosenfeld's interpretation of the wave function in 1927, we argue that Rosenfeld's work can be interpreted as a first attempt to introduce the pilot‐wave theory in the context of quantum gravity and we infer that this was one of the reasons that ruled it out.  相似文献   

6.
    
The article presents the results of an experimental and numerical investigation on Azzone Visconti bridge, a 14th century arch bridge in Lecco (northern Italy). Starting from the historical data and from an extensive mechanical characterization of both the soil constituting the riverbed and of the masonry constituting the piers, the aim of the study is to investigate the bearing capacity of the bridge. A testing loading scheme defined according to the current Italian Code is adopted to check the structural behavior. A simplified finite element structural model was conceived and calibrated as a control tool to safely perform the experimental tests. Post-test nonlinear finite element analyses have allowed the prediction of the bridge bearing capacity and the definition of the bridge class according to the Italian regulations.  相似文献   

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