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91.
Oxygen is a key parameter in the degradation of archaeological material, but little is known of its dynamics in situ. In this study, 10 optical oxygen sensors placed in a 2 m deep test pit in the cultural deposits at Bryggen in Bergen have monitored oxygen concentrations every half hour for more than a year. It is shown that there is a significant spatial and temporal variation in the oxygen concentration, which is correlated to measured soil characteristics, precipitation, soil water content and degradation of organic material. In these deposits oxygen typically occurs when the air content of the soil exceeds 10–15% vol, while oxygen dissolved in infiltrating rainwater is of less importance for the supply of oxygen in the unsaturated zone. 相似文献
92.
Kristin Reynolds 《对极》2015,47(1):240-259
Many studies have documented the benefits of urban agriculture, including increased food access, job creation, educational opportunities, and green space. A focus on its social benefits has fed an association of urban agriculture with social justice, yet there is a distinction between alleviating symptoms of injustice (such as disparate access to food or environmental amenities) and disrupting structures that underlie them. Despite its positive impacts, urban agriculture systems may reinforce inequities that practitioners and supporters aim to address. This paper reports findings from a 2‐year study of urban agriculture in New York City, which found race‐ and class‐based disparities among practitioners citywide. Using the lens of critical race theory, it argues that a failure to examine urban agriculture's role in either supporting or dismantling unjust structures may perpetuate an inequitable system. The paper concludes with recommendations for urban agriculture supporters and scholars to help advance social justice at structural levels. 相似文献
93.
Enclosed, controlled environments, stretching from sites of luxury consumption to urban food production, are proliferating in cities around the world, utilising increasingly advanced techniques for (re)creating and optimising microclimatic conditions for different purposes. However, the role of automated control systems—to filter, reprocess and reassemble atmospheric and metabolic flows with growing precision—remains under-researched. In this article, we explore the phenomenon of automated environmental control at three sites in the UK city of Sheffield: a botanical glasshouse, a luxury hotel and a university plant growth research lab. In doing so, we first show how controlled environments are constituted through specific relations between the inside and outside, which are embedded in inherently political urban contexts and processes. Second, we identify the technical and ecological tensions and limits of indoor environmental control at each site which limit the scope of automation, and the considerable amount of hidden labour and energy required to maintain and restabilise desired conditions. Drawing on these more established examples of ecological interiorisation in a key moment of transition, we raise urgent questions for critical urban and environmental geographers about the possible futures of controlled environments, their practical or selective scalability, and who and what will be left “outside”, when they are emerging as a strategic form of urban adaptation and immunisation in the face of converging ecological pressures. 相似文献
94.
Daniela Kraemer 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》2020,90(1):40-54
A contentious issue for Pacific Islanders, as well as researchers of the Pacific Islands, is ni-Vanuatu notions of ‘belonging’ to urban centres. Previous research in Vanuatu has shown that despite generations of people born and raised in Port Vila, the nation's capital, the urban centre is not generally perceived as a ‘place’ to which urban migrants can say they are from. For many, exclaiming that one is ‘from’ town is tantamount to admitting one has ‘no place’. This paper, based on fieldwork among a group of urban young men in Freswota, a residential community of Port Vila, argues that in contrast to this, Freswota young men are generating a new locative identity. Their urban community rather than their parents' home island places is emerging as their primary location of belonging and the source of their sense of self, personhood and social identification. As such, these young men are the urban autochthones of the country. 相似文献
95.
This article explores the social and material repercussions of middle class aspirations in a system that is still infused by socialist aesthetics in Maputo, Mozambique. We argue the activation of “middle classness” reproduces ingrained inequalities and boundaries. This is demonstrated through two ethnographic case studies of urban housing, long central to imaginaries of prosperity. First, fearing downward mobility, members of the upper middle class seek to embody a liberal ideology of “autonomy”, while simultaneously being dependent on state structures. Second, members of the lower middle class attempt to create enclaves to experiment with forms of privatisation normally only accessible to a privileged elite. Through this examination of the ways in which a spectrum of privileged urbanites attempts to secure their position in the face of a precarious future, the article outlines middle classness under contemporary capitalist conditions and how this is shaped by the legacies of the past. 相似文献
96.
清代东北地区基层社会的官制,长期具有"旗民分治"的特点。在各处八旗驻防地,尽管八旗制度长期存在,但在八旗制度内部,为应对旗人越旗居住、耕种,以及同一村屯内旗民杂处等若干新问题,各地方旗署将驻防地的村屯按照地域划分成若干界,拣选在旗当差的佐领、防御及世职云骑尉等,委为一界之界官,专办管界内的各项差务。清代东北各八旗驻防地的界官名称不同,设置时间不一,所司职责呈现一定的时空差异,但其旗界内基层承管官的角色不曾改变。界官所承办差务繁杂,主要是维护管界内的社会治安,承办界内旗民人等的涉农事务,督倡本界旗民的风俗教化等。东北地区的八旗界官,在咸丰至同治年间发展到鼎盛时期,自同治朝以降的同光宣三朝,因民治地方官的增设,练、防军及乡团练勇的募练,尤其是光绪末年至宣统年间四乡巡警的创办,八旗界官的职权被分割,因而迅速走向衰亡,但其作为清代东北八旗驻防地区基层行政官制演进中重要一环的地位无可替代。 相似文献
97.
Luigi Patruno 《Journal of Latin American Cultural Studies (Travesia)》2020,29(1):63-84
This article examines the under-studied film productions known in Peronist Argentina as “docudramas”. Placing documentary elements within a fictional plot, docudramas marked a significant change in the state propaganda machine and were used as a new vehicle to influence social habits. I focus particularly on Soñemos [Let’s Dream], a short film directed in 1951 by Luis César Amadori to showcase urban reforms. Through an analysis of Amadori’s docudrama in regard to its representation of the Children’s City built by the Eva Perón Foundation, I discuss relationships between entertainment, the constitution of a political hegemony, and modernisation. With film techniques such as the dissolve, Soñemos depicts the Children’s City as an enterprise capable of delivering material happiness and amplifies the narrative of a fairy tale come true promised by Evita’s social service programmes. Ultimately, the docudrama affirms the central role played by the state in the definition of the “right to a home” – from supportive benefactor to constitutive replacement. 相似文献
98.
Hu Xiangyu 《Frontiers of History in China》2020,15(4):579
The judicial system in Qing Beijing integrated both Ming and Manchu institutions. In the Ming judicial system, the first level of courts in Beijing included the Ministry of Justice and the Censorate, and on the second level was the Court of Judicial Review. During the Ming, however, this system became heavily disrupted by the intelligence security apparatuses, like the Eastern Depot. In the Manchu system, on the first level of courts was the banner company captains and on the second level was the Ministry of Justice. After 1644, the Ming’s institutional legacies and lessons remained so important to Manchu rulers that they eventually created an integrated legal system that primarily drew from the Ming system. This integration reflected the Qing dynasty’s endeavor to adopt Ming institutions. Prince Regent Dorgon insisted upon judicial separation on the first level of the courts—Censors of the Five Wards could not settle cases involving banner people, nor could the banner system handle cases involving civilians—while the Shunzhi emperor and his successors wanted judicial unity in Beijing and ordinary banner people and civilians to be adjudicated by the same courts. 相似文献
99.
Marica L. Pecorelli Rodolfo Epicoco 《International Journal of Architectural Heritage》2020,14(4):630-644
ABSTRACTThe interest in automatic modal parameter extraction techniques has increased significantly in recent years because of the rising demand for Continuous Structural Health Monitoring (CSHM) of civil structures and infrastructures. The wider use of CSHM is related to its capability for early damage detection and therefore to its usefulness for planning maintenance and strengthening interventions. This article presents the main steps followed in creating a robust routine to run on an online basis the first-ever Continuous Vibration-Based Structural Health Monitoring (CVB-SHM) of a large masonry oval dome, i.e., the dome of the Regina Montis Regalis Basilica, also known as Sanctuary of Vicoforte. The procedure uses an output-only stochastic subspace identification method complemented by an automatic analysis applied to identification results, which are typically provided in terms of stabilization diagrams. In this study, the fully automatic procedure also includes a hierarchical clustering algorithm to separate authentic from spurious modes. 相似文献
100.
敦煌文献中保存了许多唐五代时期地方各级水利官吏的设置运作状况记录。唐代前期设都水令,为当时敦煌“统以千渠”的最高级别水利官员。中唐吐蕃统治时期设“水官”“部落水官”以及“水监”“部落水监”“地方总水监”。晚唐五代归义军时期专设水司,长官为都渠泊使,下设多名水官。敦煌绿洲四界及寿昌灌区分别设置多名有特殊责任的水官“平水”,以“平治水利”,平水“相量”为务。此外,每条灌渠、每座斗门均设渠头或斗门长,属基层一级。这套水利官吏系统层层负责,相互配合,有效保证了农田灌溉顺利进行。同时敦煌民间还自发地组织起一批“渠人社”,这对地方政府水利管理体系是有益的补充。研究历史上水利官吏系统及其运作状况,对今天河湖运行和治理管护也具有借鉴作用。 相似文献