Hydraulic Evaluation of the Design and Operation of Ancient Rome's Anio Novus Aqueduct

This paper evaluates conveyance and flow characteristics for the Anio Novus, the aqueduct bringing water from the greatest distance to ancient Rome. Travertine accumulations, deposited from water on floor and walls, were used to reconstruct the flow rate and associated spatial and temporal variations. Hydraulic quantities (e.g., flow depth and velocity) markedly varied over the course of the aqueduct, implying that constraints such as topography and construction techniques were combined with hydraulic considerations to determine the aqueduct layout. Design practices differed along the aqueduct and channel size design was not based exclusively on anticipated carrying capacity, tending towards larger‐than‐necessary design based on experience.     

故宫中和殿某中金檩断裂分析

勘查发现,故宫中和殿明间某中金檩在与上部爬梁相交位置出现局部断裂,造成下部中金枋产生较大挠度.为探明该中金檩产生断裂的原因,采取理论计算与数值模拟相结合的方法,对中金檩、中金枋体系进行了分析.基于榫卯连接边界条件的特征,分别考虑中金檩与中金枋叠合、中金檩与中金枋分离、中金檩完全断裂等三种工况,建立了中金檩-枋体系的受力模型,进行了静力分析,获得了中金檩、中金枋的变形及内力分布特征,讨论了中金檩断裂破坏的影响因素.结果表明:由于中金檩在爬梁作用位置截面削弱,造成中金檩自身拉、压、弯承载力不足,从而导致中金檩产生断裂;中金檩与中金枋分离条件下,中金檩断裂造成的中金枋内力增加,且比檩枋叠合条件更明显;中金檩完全断裂后,将造成中金枋内力及变形剧增,威胁中金枋安全.因此,对中金檩采取及时有效的加固措施极其重要.研究结果将为中金枋采取加固措施提供理论参考.     

微生物诱导矿化修复阿尔寨石窟红砂岩壁面酥碱病害试验研究

阿尔寨石窟寺是内蒙古地区规模最大且保存最为完整的石窟寺建筑群,其蕴含了珍贵的关于历史、宗教、科学、文化的艺术价值,被誉为“草原上的敦煌”。由于当地典型的沙旱寒区气候特征,酥碱成为石窟壁面最为严重的病害之一,目前阿尔寨石窟正处于保护阶段,因此通过室内对病害进行模拟和研究尤为重要。本研究通过微生物诱导碳酸钙沉淀(MICP)技术,对以红砂岩风化土为基质的壁面的酥碱病害进行修复,通过激光粒度分析了病害前后土颗粒粒径的变化,提出酥碱高度、酥粉体积、盐壳厚度的量化指标用以评价病害的发展程度。基于微生物矿化技术生成矿化覆膜对病害进行抑制,推荐使用微生物菌液浓度OD₆₀₀大于1.5的具有耐盐碱性能的矿化菌株,修复后酥碱高度下降幅度大于20%,酥粉体积下降幅度大于30%,盐壳厚度下降幅度大于25%。研究成果对生物矿化技术应用于红砂岩石窟壁面的酥碱病害的修复进行试验验证和可行性评估,为绿色生态环保的岩壁病害修复与加固技术的推广应用进行科学预研。     

COMPARISON AND TRANSFER – A FRUITFUL APPROACH TO NATIONAL HISTORY?

The aim of this article is to discuss how a combined comparative and transnational approach can widen our understanding of historical change. By using examples from the first wave of the women's movement in Sweden and Canada we argue that exploring national differences, investigating differences in class and political culture and finally even tracing the transfer of resources and ideas could open up for new perspectives in gender history. Comparisons of women's organizing in different countries, but within the same international organizations, could help us to discern common structures that otherwise tend to be regarded as unique in one national context. In addition, such an approach can help to highlight specific national opportunities, cultures or strategies influencing the outcome of women's organizing.     

The nonprofit arts organization concept and its transformation in Korea

ABSTRACT

After the Korean War, both the autocratic and later democratic South Korean governments actively fostered the development of Korea’s arts sector, in part by emulating the organizational and legal structures of U.S. nonprofits. Yet, in this policy transfer, Korea has taken a different path, notably rearticulating the U.S.-style hands-off facilitation model to reflect and accommodate Korean political, institutional, and cultural exigencies. We analyze the effects of the resulting cultural policy on Korean public arts institutions, using documentary evidence and narratives from our case studies of two national arts organizations restructured by the government: The National Theater Company of Korea and the Seoul Arts Center. We employ the concept of cultural statism, conditioned by "culture as glorification," resource dependence, and path dependence, to understand the development of Korea’s public arts sector. Specifically, we consider: the government’s desire to use the arts to enhance its image on an international stage shaped by western liberal democratic values; arts leaders’ desire for reliable support (resource dependence); and the tendancy of Koreans to want to be associated with the stability and prestige of the government (path dependence).     

Instrument Transfer as Knowledge Transfer in Neurophysiology: François Magendie's (1783–1855) Early Attempts to Measure Cerebrospinal Fluid Pressure

François Magendie's (1783–1855) experimental model for measuring blood pressure in animals, which he developed in 1838, had a major impact on French physiology in the nineteenth century, especially upon Etienne-Jules Marey (1830–1904) in Paris. In due course it was also adopted by other European investigators, such as the Leipzig physiologist Carl Ludwig (1816–1895), and by clinicians who developed it into a major measuring tool. Historians of science, however, have paid hardly any attention to Magendie's further laboratory investigations conducted with the assistance of Jean-Louis Marie Poiseuille's (1799–1869) sphygmomètre (blood pressure meter). After having used the apparatus to conduct his experiments on a variety of blood vessels, Magendie also applied the sphygmomètre in 1840 to the ventricular system of the brain in order to measure cerebrospinal fluid (CSF) pressure. But the scope of this new procedure had yet to be defined: the new measuring device invited many speculative interpretations about the meaning of CSF flow for the physiology of the ventricular system in healthy and diseased brain function. As such, Magendie's experiments produced phenomena in very heterogeneous knowledge areas, and CSF measurement was situated at the interface of quite disparate investigative spaces regarding the structure and function of the brain. In his textbook Leçons sur les Fonctions et les Maladies du Système Nerveux (Lectures on the Functions and Diseases of the Nervous System), Magendie described extending application of the measuring “apparatus of Poiseuille” from blood vessels to parts of the brain. The instrument thus became something of a liquidodynamomètre (liquor dynamometer), that paved the way for later applications, including (after 1896) diagnostic intracranial pressure (ICP) measurement by Theodor Kocher (1841–1917) and Harvey Cushing (1869–1939). The current paper focuses on the experimental contingencies that prompted the instrument transfer in Magendie's laboratory and opened up new epistemological perspectives for research in neurophysiology.     

Numerical simulations of amethyst geode cavity formation by ballooning of altered Paraná volcanic rocks,South America

Numerical modelling by finite element methods provides two significant insights into the formation of the giant amethyst geodes of the Paraná volcanic province: the conditions needed to open the cavities and the conditions that control their size and shape. Giant amethyst geodes were formed in the Cretaceous (135 Ma) in altered volcanic rocks by water vapour pressure (Δp) at about 0.5 MPa under an altered basalt cover of 5–20 m. Only rocks with Young’s modulus values (E) in the range 1–2 GPa can sustain ballooning, which is the growth of a cavity in a ductile medium by the pressure of water and its vapour. The size of the proto‐geode is dependent on the water vapour pressure, which is directly related to thickness of the overlying basalt. Varying the yield points causes the formation of either prolate or oblate cavities. A low transition point (smaller than 0.18 MPa) generates a prolate‐shaped cavity, whereas a high transition point (larger than 0.18 MPa) generates oblate proto‐geodes. Proto‐geodes are smaller when Young’s modulus is higher (rock is less altered) or when water vapour pressure is lower (because of thinner overburden of basalt). The calculations are an indication that the processes operative in the altered basalts led to the opening of giant cavities by ballooning.     

Observations on the Geographical Dimensions of Russia's Resource Abundance

A UK-based authority on Russia's economic geography examines the geographical dimensions of Russia's resource abundance, devoting particular attention to the spatial redistribution of resource rents generated by extraction, primary processing, and fabrication. After establishing Russia's credentials as a "resource-abundant economy," the author identifies the country's resource regions and considers their relative importance in terms of population, territory, and national economic contribution. He then considers the various dimensions (and different geographies) of resource rent, focusing on the oil and gas sector. The paper extends Gaddy and Ickes' (2005) macro-economic assessment and discusses the consequences of rent redistribution for interregional income flows as well as Russia's territorial cohesion. Journal of Economic Literature, Classification Numbers: O11, O13, O18, Q30. 5 figures, 1 table, 55 references.     

从青州到济南:宋至明初山东半岛中心城市转移研究——一项城市比较视角的考察

本文从城市发展的内外部环境、城市本体、城市腹地三个方面,对宋金元时期青州与济南二城进行了比较研究。研究发现,在内外部环境方面,北宋时期,青州、济南二城均较为优越,金元时代却截然相反。从城市本体的相关指标来看,城市风貌上,北宋时期的济南城尚落后于青州城,金元时期青州城因迭遭战火,城市风貌已大不如济南;城市占地规模上,北宋时期青州城的占地规模明显大于济南城,而金元时代的济南城已后来居上。在城市腹地发展水平方面,宋金元时期,至少是金元时代,济南城市腹地的户口数量和经济发展程度已经完全超越青州城的腹地。进而指出,金元时代,至少在元代,山东半岛的经济中心城市实际已经转移至济南,明洪武九年(1376年)山东承宣布政使司由青州到济南的移治,只不过是行政中心"追逐"经济中心,对济南经济中心城市地位的一种政治承认而已。     

《商务谈判》在实践中的教学研讨

近年来社会对高校工商管理专业人才的需求趋势发生了改变,不但要求学生具有扎实的理论知识还特别强调学生具备较强的实践参与能力。《商务谈判》课程属于专业设置中的应用型专业课程,因而在新的就业形势下,教师在教学过程中应该改变以往重视理论而轻视实践的教学方式。本文针对课程教学中的实践环节的教学目标和要求,提出了教学方式和手段创新的具体方法,并介绍了在实际操作中的经验。