The Problems of Utilizing ‘Direct Experience’ in Geography Education

In response to the various calls for sustainable development, a range of activities has been initiated by central and local government, business, NGOs and other institutions. In this paper, the authors focus on the important learning context of higher education. They review the agenda established at Rio and, through a critical examination of developments within the UK, comment on issues and challenges facing the sector.     

Effect of AAC Infill Walls on Structural System Dynamics of a Concrete Building

The effect of autoclaved aerated concrete (AAC) infill walls on the structural system dynamics of a two-story reinforced concrete building is investigated using its finite element structural model, which is calibrated to simulate the acceleration-frequency response curves from its forced vibration test. The model incorporating the AAC infill walls by equivalent diagonal struts captures the increase in lateral stiffness of the building and the torsional motions induced due to the asymmetrically placed AAC infill walls. A higher strut width coefficient than in ASCE/SEI 41-06 is recommended to model the stiffness of the AAC infill walls in the elastic range.     

金塔县长城破坏风险影响因素调查与研究

本文以甘肃省金塔县为对象,对长城资源调查工作所记录的长城遗迹进行抽样复查。对长城本体存状及变化情况、长城所处环境、破坏因素、保护管理状况等进行记录与分析,并从中分辨出长城破坏的主要原因,以期对长城遗产的合理监测提供依据,为长城保护工程下一阶段工作的开展奠定基础。     

潮湿环境下古象牙的现场提取与保护——以三星堆遗址三号坑出土象牙为例

2020年10月,三星堆遗址新发现祭祀坑正式启动考古发掘工作。随着发掘工作的推进,大量象牙相继出土。由于长期埋藏于潮湿的地下环境,象牙基本处于饱水状态,保存状况较差。为了使象牙保持相对稳定的状态,在考古发掘现场针对不同象牙的发掘情况,采用高分子绷带进行固形处理,然后整体提取回实验室清理。清理完成的象牙,经过保湿杀菌处理后存放至低温高湿专用库房。三星堆遗址三号祭祀坑出土象牙的成功提取与保护,表明医用高分子绷带具有超越石膏提取法的应用优势,对类似出土遗物的现场保护工作有一定的借鉴作用。     

Narratives and counter-narratives of climate change: North Atlantic glaciology and meteorology,c.1930–1955

This paper seeks to uncover narratives of climate change shaped within two distinct but related research communities in glaciology and meteorology, both institutionally located at the Stockholm Högskola, later Stockholm University, and with widespread collaborative networks in the Nordic countries, the United Kingdom, and the United States. During the 1930s, Stockholm glaciology under Hans W:son Ahlmann provided an early theory of ‘polar warming’, based on solid field data from the North Atlantic and Arctic realm, but remained resistant to ideas of human climate forcing and thus lost a lot of its emerging policy influence. Stockholm meteorology under Carl-Gustaf Rossby followed a different trajectory. Based on geophysical theory and computer science experimentation funded by military sources on both sides of the Atlantic, the Rossby school established an early institutional acceptance of greenhouse explanations of climate change with strong links to policy. This account of divergent research agendas, differential extra-scientific conditions, and contradictory representations of the direction and causes of climate change should caution against viewing the history of climate science and policy as a cumulative affair based on ever more precise and better knowledge. The narratives presented here highlight, on the contrary, the importance of broad science politics as well as local and disciplinary methods, traditions, and institutional trajectories in shaping attitudes among scientists to climate change.     

Lithology and fluid prediction from amplitude versus offset (AVO) seismic data

Seismic reflection data as used in the oil industry is acquired and processed as multitrace data with source‐receiver offsets from a few hundred metres (short offset) to several kilometres (long offset). This set of data is referred to as ‘pre‐stack’. The traces are processed by velocity analysis, migration and stacking to yield a data volume of traces with ‘zero‐offset’. The signal‐to‐noise enhancement resulting from this approach is very significant. However, reflection amplitude changes in the pre‐stack domain may also be analysed to yield enhanced rock physics parameter estimates. Pre‐stack seismic data is widely used to predict lithology, reservoir quality and fluid distribution in exploration and production studies. Amplitude versus offset (AVO) data, especially anomalous signals, have been used for decades as indicators of hydrocarbon saturation and favourable reservoir development. Recently, enhanced quantification of these types of measurement, using seismic inversion techniques in the pre‐stack domain, have significantly enhanced the utility of such measurements. Using these techniques, for example, probability of the occurrence of hydrocarbons throughout the seismic data can be estimated, and as a consequence the many pre‐stack volumes acquired in a three‐dimensional (3D) can be survey, reduced to a single, more interpretable volume. The possibilities of 4D time lapse observation extend the measurements to changes in fluid content (and pressure) with time, and with obvious benefits in establishing the accuracy of dynamic reservoir models and improvements in field development planning. As an illustration, recent results from the Nelson Field (UK North Sea), are presented where we show the method by which probability volumes for oil sands may be calculated. The oil–sand probability volumes for three 3D seismic datasets acquired in 1990, 1997 and 2000 are compared and production effects in these data are demonstrated.     

宋朝西南边疆民族地区的土地赋税政策

除少数几次“开边”之外,宋朝政府在西南边疆民族地区实行较为温和的开拓政策,“纳土”以及“赐土”行动伴随两宋始终。在所谓“变夷为汉”的实施过程中,对夷民征收赋税是一项关键措施。宋政府的土地赋税政策并不确定,各地的实际情况有很大差异。田土交易也大体经历了从禁到开禁．到再禁三个阶段。     

Practical Application of Digital Photogrammetry for Fieldwork in the American Midwest: An Example from the Middle Ohio Valley

The use of close-range digital photogrammetry for field documentation has been steadily increasing in the past half decade in several parts of the world. However, this technology has not been widely utilized in archaeological contexts in the American Midwest. We explore the utility of close-range photogrammetry in this region with examples from the Guard site (12D29), a Fort Ancient village located in southeastern Indiana. This article outlines the methods utilized for production of georeferenced 3-D models of several units excavated during the 2016 field season. These models as well as plan and profile orthophotos derived from them act as important supplements to standard photographs and drawings made in the field and easily integrate with the site GIS. Overall, we found close-range digital photogrammetry to be very useful to better document excavation details, doing so for limited cost and time expenditure.     

宁波“小白礁Ⅰ号”船体病害调查和现状评估

宁波"小白礁Ⅰ号"清代沉船位于浙江宁波象山石浦北渔山岛海域,于2014年发掘出水。经过长期的水下埋藏,"小白礁Ⅰ号"残存船体构件遭受多种病害破坏,亟需开展保护修复。通过对"小白礁Ⅰ号"船体构件的全面调查,并采样进行了树种、含水率、形貌、化学组分、可溶盐及微生物等多方面的分析,得知残存船体大部分保存状况较好,但不同部位保存状况差别较大,病害类型多样。相关分析和评估工作为船体后续保护处理提供了依据。