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61.
Abstract:  This paper identifies and explains the pattern of memorialization in New Zealand for English nurse Edith Cavell, arguing that while the influences of empire and colonial mimicry provided a strong overarching framework, local context and parochial expressions were also strong at the colonial edge. In 1915 Cavell was executed by the occupying German forces in Belgium for her resistance work. The general transnational pattern of remembrance that resulted from the huge reaction to her death is explained. The paper then turns to the New Zealand memorialization of Cavell. With reference to monuments for other medical women, and addressing where Cavell does not appear in the landscape, the last section contextualizes Cavell's New Zealand memorialization.  相似文献   
62.
Chemical methods are generally chosen to monitor soil pollution but magnetic measurements proved to yield additional information at low cost and less time consumption. In this investigation, the novel use of rapid and non-destructive magnetic measurements to characterize Br levels in Xuzhou (China) urban roadside soils was reported. X-ray fluorescence spectrometry (XRF) was used to quantify Br in the soil samples. Data from 21 roadside soil samples confirm Br contamination, with a mean level of 4.36 mg kg−1 and a range of 2.4–8.7 mg kg−1. These values are higher than that of unpolluted soils in Xuzhou that averages 1.1 mg kg−1. Hierarchical clustering analysis shows Br in Xuzhou roadside soils is mainly from road traffic. Clear correlations between Br levels and simple magnetic parameters [mass specific susceptibility (χ LF), susceptibility of anhysteretic remanent magnetization (χ ARM), saturation isothermal remanence (SIRM)] are observed. The present study shows that these three magnetic parameters can be used as a proxy for Br levels in Xuzhou urban roadside soils.  相似文献   
63.
圆形标志中心子像素定位方法的研究与实现   总被引:18,自引:1,他引:18  
采用回光反射材料制作圆形回光反射标志,经摄影后得到标志的“准二值影像”;对标志的椭圆影像进行亚像素边缘提取,经最小二乘椭圆拟合后得到标志中心的子像素级位置。试验表明,可以达到0.02像素的定位精度。  相似文献   
64.
对中国大陆科学钻探主孔的岩心进行了声发射测量,确定了301~1531m深度的最大主应力。并与钻孔崩落法(深度1269~1655m)测量结果进行了对比,结果表明,声发射测量所得测值基本上落在钻孔崩落法测值的趋势线上,两种方法所得结果一致,说明测量结果可信。测量结果表明科学钻探主孔地应力大小随深度增加,在浅部301m最大主应力为13.4MPa,在深部1655m为55.2MPa。随深度的增加率为0.0279MPa/m。最大主应力方向为N54°±3.3°E,且方向不随深度变化。  相似文献   
65.
文章通过对贵州省大方县以公鸡山地裂隙实地调查,认为地裂隙的形成主要与公鸡山一带地下采煤有关。即采煤虚脱,沿先存构造断裂拉张而成。同时叙述了地裂缝特征及危害,并提出防灾减灾措施。  相似文献   
66.
城市热岛效应监测方法研究进展   总被引:16,自引:0,他引:16  
城市热岛效应是一种由于城市建筑及人们活动导致的热量在城区空间范围内聚集的现象,是城市气候最明显的特征之一.由于城市热岛影响因素以及相互关系的复杂性,为了精确细致地描述其时空分布,人们采用了多种方法来研究城市热岛现象,主要归纳为:气象站法、定点观测法、运动样带法、遥感测定法以及模拟预测等.最后,认为各种测定方法都存在一定的缺陷,建议多种测定方法综合运用.  相似文献   
67.
等距等高电磁波测距三角高程测量及精度分析   总被引:7,自引:0,他引:7  
介绍了等距等高电磁波测距三角高程测量的原理,详细深入地分析了这种高程测量方法的精度,通过计算和作图表示,可直观地反映在不同条件下的精度变化情况,讨论了代替国家等级水准测量的范围和条件,可供生产实际和进一步研究参考。  相似文献   
68.
A generic network design in close range photogrammetry is one where optimal multi-ray intersection geometry is obtained with as few camera stations as practicable. Hyper redundancy is a concept whereby, once the generic network is in place, many additional images are recorded, with the beneficial impact upon object point precision being equivalent to the presence of multiple exposures at each camera position within the generic network. The effective number of images per station within a hyper redundant network might well be in the range of 10 to 20 or more. As is apparent when it is considered that a hyper redundant network may comprise hundreds of images, the concept is only applicable in practice to fully automatic vision metrology systems, where it proves to be a very effective means of enhancing measurement accuracy at the cost of minimal additional work in the image recording phase. This paper briefly reviews the network design and accuracy aspects of hyper redundancy and illustrates the technique by way of the photogrammetric measurement of surface deformation of a radio telescope of 26 m diameter. This project required an object point measurement accuracy of σ  = 0·065 mm, or 1/400 000 of the diameter of the reflector.  相似文献   
69.
The electrical aerosol spectrometer (EAS) of the parallel measuring principle at Tartu University is an efficient instrument for rapid measurement of the unstable size spectrum of aerosol particles. The measuring range from 10 nm to 10 μm is achieved by simultaneously using a pair of differential mobility analyzers with two different particle chargers. The particle spectrum is calculated and measurement errors are estimated in real time by using a least-squares method. Experimental calibration ensures reliability of measurement. The instrument is well suited for continuous monitoring of atmospheric aerosol.  相似文献   
70.
The paper presents a numerical investigation aimed at evaluating the improvements achievable through devices for passive seismic protection of buildings based on the use of shape memory alloys (SMA) in place of conventional steel or rubber devices. To get some generality in the results, different resisting reinforced concrete plane frames were analysed, either protected or not. ‘New’ and ‘existing’ buildings were considered depending on whether seismic provisions are adopted in the building design or not. Base isolation and energy dissipation were equally addressed for both conventional and innovative SMA‐based devices. Fragility analyses were performed using specific damage measures to account for comparisons among different damage types; the results were then used to estimate quantitatively the effectiveness of the various protection systems. More specifically, the assessment involved a direct comparison of the damage reduction provided by each protection system with respect to the severe degradation experienced by the corresponding non‐protected frame. Structural damage, non‐structural damage and damage to contents were used on purpose and included in a subsequent phase of cost analysis to evaluate the expected gains also in terms of economic benefits and life loss prevention. The results indicate that base isolation, when applicable, provides higher degrees of safety than energy dissipation does; moreover, the use of SMA‐based devices generally brings about better performances, also in consideration of the reduced functional and maintenance requirements. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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