Geochemical evidence for the manufacture,logistics and supply‐chain management of Emperor Qin Shihuang's Terracotta Army,China

Non‐invasive materials characterisation of reconstructed statues of Emperor Qin Shihuang's Terracotta Army has revealed distinct micro‐geochemical patterning within the clay paste used in their manufacture. The significance of this is explored in terms of the production sequence, logistics and supply‐chain management involved in the construction of this enormous funerary assemblage. Of particular interest is a compositional distinction between figures marked with the names ‘Gong’ (宫) and ‘Xianyang’ (咸阳). These seem to represent the products of two workshops involved in the supply of ceramic objects for this ambitious, large‐scale building project undertaken by the Qin Empire during the third century bce .     

Refugee Shelter in a Logistical World: Designing Goods for Supply‐Chain Humanitarianism

Focusing on the design and production of the IKEA Foundation “Better Shelter” and on its use in a camp on the island of Lesvos, Greece, this article explores the role of logistical calculative rationales in the provision of emergency shelters to refugees. It argues that an engagement with the critical geographies of logistics contributes to the study of such “humanitarian goods” in two main ways. First, it foregrounds the technologies that allow emergency shelter products to circulate across production sites and disaster and border zones, and their connections to broader infrastructures and commercial networks in what recent literature has called “supply‐chain humanitarianism”. Second, a logistical lens highlights the disruptions that characterise the production and usage of emergency shelter products. The analysis adds to a body of work that exposes humanitarian technology and design as sites of friction, deeply embedded in global processes of bordering and accumulation.     

基于三维扫描模型的兵马俑足踝有限元分析

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。     

多种科技方法在古月桥勘察修缮设计中的应用

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。     

Quantifying artefacts over time: Interval estimation of a Poisson distribution using the Jeffreys prior

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.     

Hybrid finite element–finite volume discretization of complex geologic structures and a new simulation workflow demonstrated on fractured rocks

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.     

The Origin and Archaeometallurgy of a Mixed Sulphide Ore for Copper Production on the Island of Kea,Aegean Sea,Greece

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.     

中国外资银行空间网络演化的结构特征及其影响因素

本文基于外资银行网点数据,借鉴连锁型网络模型,构建了1990年、2001年和2015年中国外资银行空间网络并分析演化结构特征,最后借助条件Logit模型探讨了外资银行空间分布的影响因素。研究表明：①中国外资银行空间网络小世界网络特征明显,具有较大的集聚系数和较小的平均路径长度,网络中局域小集团网络化特征和核心-边缘结构明显。②随着网络规模的平稳增长,网络的有序性呈现出增强趋势,网络中金融连接度和金融可达性增加,金融传输效率和组织效率进一步提高,核心-边缘结构现象有所加剧。③外资银行空间分布的主导因素在不同时期不一样,1990年主导因素是市场机会和区位效应,2001年和2015年的主导因素是金融集聚,但指标的具体影响概率有所降低。     

位置照片表征的景区游客拍照行为时空模式

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。