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41.
Life-history or personal narrative techniques have considerable potential as a way of recovering hidden histories, contesting academic androcentrism, and reinstating the marginalized and dispossessed as makers of their own past. Drawing on a large methodological literature on life-history collection, and applications of these techniques in Africa, we argue that geographers might explore these methodologies as a means of recovering lost geographies and venting alternative voices in academic texts. Drawing on our own project on Swazi migrant women, we suggest that life-histories cannot, however, be seen purely as vehicles for the delivery of uncontaminated fact about the past. Rather personal narratives should be viewed and interpreted as interactive texts. This leads us to a consideration of a number of methodological and interpretive issues surrounding life-history collection: the positional advantages of insider status, the “terrible assymetries” of the interview process, and the power (and pitfalls) of narrative forms of representation. 相似文献
42.
Installation of a vertical slurry wall around an Italian quarry lake: complications arising and simulation of the effects on groundwater flow 总被引:1,自引:0,他引:1
Slurry walls are non-structural barriers that are constructed underground to impede groundwater flow or manage groundwater
control problems. The study area is in the Piemonte plain (Italy), close to the River Po. Quarrying works carried out below
the piezometric surface created two big quarry lakes. The local groundwater system is characterized by a lower semi-confined
aquifer, which is overlain by a semi-permeable bed of clayey peat (aquitard) and an upper unconfined aquifer. Locally, the
peat fades away and the granulometry of this horizon becomes silty sandy. A planned enlargement of the quarry will increase
the size and depth of the quarry lakes. So the aquitard bed between the two aquifers will be damaged, creating a mixing rate
of groundwater. Such a procedure would not be compatible with the presence of two municipal wells upstream from the quarries.
Consequently, the installation of a vertical diaphragm (slurry wall) is recommended to separate the aquifers and to act as
a filter for the groundwater flowing from the unconfined to the semi-confined aquifer. To predict the consequences caused
by the installation of the vertical diaphragm separating the unconfined aquifer and the semi-confined one, a specifically
adjusted finite-difference model was used. The model showed a maximum rising of the water table equal to 12 cm, just upstream
of the diaphragm and for a distance of about 100 m, and a maximum lowering of 2 cm just downstream of the diaphragm. However,
the slurry wall would not cause any change in the piezometric head in the area where there are municipal wells and, hence,
will not have any negative effect on the functionality of the municipal wells. Moreover, the migration of water from the unconfined
aquifer through the vertical diaphragm will stimulate a series of attenuation and auto-depuration processes of eventual contaminants.
These processes are due to the higher crossing time that the groundwater flow takes to go through the vertical barrier (t
a = 96.5 days, whereas for the horizontal semi-permeable layer t
a = 9.6 days). So, the vertical diaphragm can be a resolutive element, representing a mediation and separation factor between
the unconfined and the semi-confined aquifers along the border of the quarrying areas, and a protective barrier for the water
quality of the quarry lake and the semi-confined aquifer. 相似文献
43.
根据2000~2005年安徽省星级饭店统计资料,利用变异系数这一度量标准分析了安徽省饭店在时间序列上和星级结构上的地域差异,结果表明:随着时间的变化饭店总数在各市间的差异在渐渐缩小.星级结构上五星级饭店地域分异程度最大,其次依次为一星级、四星级、三星级和二星级,通过安徽省各市国内旅游收入区位商和餐饮住宿业就业人员区位商与各市星级饭店数量相对水平的比较,找出不符合一般趋势的城市加以讨论.最后,运用SPSS分析软件对安徽省17个地市的星级饭店发展水平进行聚类分析,并讨论了运行结果所分出的4类城市,提出了饭店业发展的若干建议. 相似文献
44.
Abstract: So-called 'boy racers' form a subculture, which is subject to ongoing public scrutiny and media attention, usually negative. This study aimed to deconstruct the term 'boy racer' and to explore the subculture in detail, within the context of Christchurch, New Zealand, using a phenomenological ethnographic approach. This included conducting semistructured interviews and observing the activities of participants. Results show the subculture has a relatively diverse membership and a range of associated behaviours, activities and attitudes. Moreover, performances within the subculture are linked to place, and are seen by other members of the community as threats to normative boundaries. 相似文献
45.
The essential of feature matching technology lies in how to measure the similarity of spatial entities.Among all the possible similarity measures,the shape similarity measure is one of the most important measures because it is easy to collect the necessary parameters and it is also well matched with the human intuition.In this paper a new shape similarity measure of linear entities based on the differences of direction change along each line is presented and its effectiveness is illustrated. 相似文献
46.
本文从比较文化学与文化地理学的角度,较全面、系统地分析比较了东西文化的诸多差异,侧重剖析了东西方文化差异的地理原因,评介了“东化”与“西化”之争的基本观点,说明了东西方文化的关系及其发展前景。 相似文献
47.
Burša Milan Kouba Jan Müller Achim Raděj Karel True Scott A. Vatrt Viliam Vojtíšková Marie 《Studia Geophysica et Geodaetica》1999,43(1):1-6
Geopotential values W of the mean equipotential surfaces representing the mean ocean topography were computed on the basis of four years (1993 - 1996) TOPEX/POSEIDON altimeter data: W = 62 636 854.10m
2
s
–2
for the Pacific (P), W = 62 636 858.20m
2
s
–2
for the Atlantic (A), W = 62 636 856.28m
2s–2
for the Indian (I) Oceans. The corresponding mean separations between the ocean levels were obtained as follows: A – P = – 42 cm, I– P = – 22 cm, I – A = 20 cm, the rms errors came out at about 0.3 cm. No sea surface topography model was used in the solution. 相似文献
48.
顾及密度差异的河系简化 总被引:7,自引:2,他引:7
河系简化是地图综合中经常需要处理的任务,其难点主要在于依据上下文环境对河流进行结构化选取,以保持河网密度差异等宏观特征。提出一种新的河流等级规则,依据河流的各级支流的数量确定河流的等级,以反映河流的密度差异;设计一种结合河流等级、长度与所在层次的综合指标进行河流选取;探讨在自动构建河系树的基础上计算河流等级、所在层次等指标的方法;最后使用综合指标进行河流结构化选取试验。结果表明,以新等级规则为基础的综合指标切实可行,能够在一定程度上保持河网密度的区域差异。 相似文献
49.
人工神经网络在色彩变换中的应用 总被引:1,自引:0,他引:1
给出了一种针对数字彩色硬拷贝的输出设备,建立了由CIE色度值到设备控制值色彩变换的神经网络方法。基于蒙版方程的颜色传递机理,由色度密度变量实现色彩变换。结果表明,该色彩变换对各种色调均有较明显的校正作用,且保持了高饱和色的饱和度。 相似文献
50.