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1.
利用三维扫描技术获取兵马俑残片的三维点云数据,结合Geomagic Studio和Hypermesh建立高精度的兵马俑足踝残片三维实体网格模型。通过基于ABAQUS的重力作用下的有限元分析,研究足踝部分的Von Mises应力和变形特征,以确定足踝处的受力薄弱部位。为进一步探究模型各残片的最佳点云简化比例,采用点云简化模型进行相同工况的有限元分析,以验证点云简化的可靠性。结果表明:结构在重力作用下可保持安全稳定的状态,相对薄弱部位位于左腿足踝处;对于大部分残片,其最佳简化比例在60%~70%,简化后可有效缩短模型实体化处理时间;采用简化模型得到的有限元结果,其最大Mises应力相比于原始模型的误差小于15%,且应力云图和变形图形状接近,模型简化具有可靠性。  相似文献   
2.
European Union spatial policies have become a key institutional context in which to study policy transfer processes in European border areas. These policies are, however, only the most recent part of these transformation processes which raises a need for more historically sensitive approaches. An historical perspective is important, since border regions are historical processes with particular path-dependent development trajectories and power structures. This paper aims to contribute to the discussion concerning the transformation of European border regions by looking at the policy transfer of regional development discourses in the Finnish Torne Valley. The study material consists of strategic development documents produced by the Finnish border municipalities and the municipal-based co-operation organizations from the 1930s to 2013. The examination, based on critical discourse analysis, shows that the transformation process is driven by national trends and the dominant planning discourse. Nevertheless, the particular border setting and local discourse on ‘united Torne Valley’ have also intertwined with political and economic processes during different time periods.  相似文献   
3.
建于南宋嘉定六年(公元1213年),位于浙江省义乌市的古月桥是折边拱桥这种桥梁发展过渡形式中不可多见的典型实证,具有极高的历史、科学、艺术、文化和社会价值。为了明确古月桥目前的状态,分析其主要威胁及病害原因,判断结构稳定性,进而制定有针对性的修缮方案,采用多种科技方法对古月桥进行了勘察和综合判断。面对桥身残破的现状,工作组采取了三维激光扫描、微观实验、结构分析等多种科技方法综合勘察,不仅较为清晰的地了解了古月桥的病害威胁,也分析了其背后致因及相互之间的联系;最终对古月桥稳定性及保存状况做出了综合判断。上述多种方法的应用,不仅相互印证了勘察结论,也为后续保护工作提供了重要的依据。  相似文献   
4.
Trust is a key mechanism for explaining the ease and frequency of knowledge spillovers within regions. While the importance of trust is virtually uncontested, there have been few attempts to rigorously disentangle the way in which trust formation is related to space and proximity. The aim of this paper is to advance the understanding of trust formation in terms of its main antecedents within the context of regional studies. This is done by reviewing the rich literature on trust formation from psychology, sociology, and organization studies and connecting it conceptually to different types of proximity. In doing so, the paper maps out a number of avenues for future research on trust and geography.  相似文献   
5.
This paper presents a new method for estimating the amount of an artefact class in use at a given moment in the past from a random assemblage of archaeological finds. The method is based on the use of simulation, since an analytical solution is computationally impractical. Estimating the number of artefacts in use at any time t is shown to follow a Poisson distribution, which allows for credible intervals to be established using the Jeffreys prior. This estimator works from minimal assumptions about the dating and duration of finds, as well as the intensity of collection, and is applied to coinage from four Roman‐period sites excavated by the Roman Peasant Project (2009–14). The result provides an estimation of the abundance of material according to an interval of certainty.  相似文献   
6.
The impacts and activities of international retailers have beenlargely ignored in the globalisation discourse. A possible reasonfor this is the absence, in international retailing, of conceptand theory that does not hang on the coat-tails of internationalproduction. The paper attempts to consider international retailingin its own right. Three linked questions are explored. Has theinternationalisation process of the large retailers resultedin an increase in the global concentration of sales? In whatways does the process of retailer internationalisation differfrom the internationalisation of production? What does the committedinternational retailer transfer to the host country during theinternationalisation process?  相似文献   
7.
The generation of computational meshes of complex geological objects is a challenge: their shape needs to be retained, resolution has to adapt to local detail, and variations of material properties in the objects have to be represented. Also mesh refinement and adaptation must be sufficient to resolve variations in the computed variable(s). Here, we present an unstructured hybrid finite element, node‐centred finite‐volume discretization suitable for solving fluid flow, reactive transport, and mechanical partial differential equations on a complex geometry with inhomogeneous material domains. We show that resulting meshes accurately capture free‐form material interfaces as defined by non‐uniform rational B‐spline curves and surfaces. The mesh discretization error is analysed for the elliptic pressure equation and an error metric is introduced to guide mesh refinement. Finite elements and finite volumes are represented in parametric space and integrations are conducted numerically. Subsequently, integral properties are mapped to physical space using Jacobian transformations. This method even retains its validity when the mesh is deformed. The resulting generic formulation is demonstrated for a transport calculation performed on a complex discrete fracture model.  相似文献   
8.
At the hill of Agios Symeon, on the island of Kea, Aegean Sea, Greece, ancient metallurgical slags with a high Pb–Zn–Cu content have been found. Thermodynamic simulations have been carried out, using the FactSage? thermodynamic database computing system, with a view to understanding the ancient metallurgical processes that produced the observed slag compositions and morphologies. The simulations demonstrate that the slag samples resulted from Cu‐making processes. It would thus appear that mixed ores were used, containing Cu2S–FeS–PbS with significant amounts of sphalerite (ZnS) as impurity. The roasted ores were reduced at relatively high oxygen potentials at ~1125°C to form Cu containing low levels of Pb, Fe and Zn.  相似文献   
9.
基于九寨沟景区的地理标记照片数据,利用Voronoi图、点中心度和马尔科夫链方法,从景点、景段和风景线尺度分析游客在景区内的拍照行为模式。根据数据呈现的时间转移峰值特征和空间转移概率特征,将景点尺度下的游客拍照行为总结为邻近快速转移、多中心慢速转移、跨越缓慢转移3种模式,景段尺度下的游客拍照行为总结为单向快速转移、跨越慢速转移两种模式,风景线尺度下的游客拍照行为总结为直接快速转移和间接慢速转移两种转移模式。景区内时空转移模式整体上呈现邻近景点、景段之间的空间转移概率较大,出现拍照高峰的时间较为接近,转移概率较高的区域都集中在热度较高的景点、景段,研究结果可以为游客规划游览路径提供理论依据,为景区管理人员提供决策支持。  相似文献   
10.
Abstract

This paper studies how the local governance reforms carried out between 1997–2014 shape state-society relations at Georgia’s local level. Drawing on Foucault’s concept of governmentality, I analyze how the reforms shape practices and actors at the local level. Research interviews with state officials at the national and subnational levels and citizens of the Georgian district Marneuli highlight both government rationalities and how people react to them. I argue that the reforms, which have been declared to promote participation and accountability, hardly contribute to bridging the huge gap between state and society, particularly with respect to the case of the Azeri minority in Marneuli. Thus far, the newly introduced formal actors at the local level, the municipalities, lack power. Societal action in absence of the state and interaction with the state via informal networks remains dominant. The study contributes to literature on state-building and transformation in Georgia by shedding light on the often-neglected local level and to the debate on external democracy promotion and policy transfer by empirically studying the effect of a policy transfer.  相似文献   
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