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801.
Paulo Cesar da Costa Gomes 《GeoJournal》2004,60(4):339-344
We are concerned here with the notion of space as a primary condition for building social relations. From this stand, we have
created two analytical matrixes that can help us characterize two modes: that of ‘being-there-in-space’ and that of ‘being-of-the-space’;
the nomospace and the genospace. While the nomospace is characterized by ‘cold’ connotations, which are ideally defined as a result of a logical option, the genospace is mainly characterized by emotional or ‘warm’ connotations, which originate from a feeling of shared nature and common destiny.
We believe that these matrixes could help us to identify the meanings of some behaviours and, therefore, make us more capable
of interpreting many dynamics that occur in modern societies. The importance of geography is justified by the existing relationship
between these behaviours and their proper spatial form.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
802.
MARIA ELISA CHRISTIE 《Geographical review》2004,94(3):368-390
ABSTRACT. The house‐lot garden in central Mexico is gendered space where changing cultural identities are negotiated, re‐created, and celebrated as “tradition” is continually redefined. No clear boundary separates the kitchen from the house‐lot garden or the private space of the household from the semipublic space of the community. During collective food preparation for religious fiestas, gendered reciprocity networks strengthen community relations and foster alliances between traditional neighborhoods and between communities in the region. At the intersection of everyday life and fiestas, food‐preparation spaces, or kitchenspaces, in the house‐lot garden are fertile areas in which to explore the cultural reproduction of nature‐society relations. They are vital to understanding gender, place, and culture in this region and represent people's symbolic connection with the land in increasingly urban contexts. This article analyzes the sense of place that Mexican women derive from their house‐lot gardens. 相似文献
803.
土钉墙空间效应和平滑破坏模式的三维分析 总被引:5,自引:2,他引:5
在实际工程中,土钉墙稳定性评估一般采用转动破坏模式,且不考虑其空间效应对设计方案的影响,其结果是有时得到的结论与实际状况不相符合.本文采用三维极限分析方法,对土钉墙空间效应和平滑破坏两个方面的问题进行了讨论,并结合一实际工程,对它们进行了分析,得到一些初步结论,以期对实际工程有一定的参考价值. 相似文献
804.
RS+GCPs获取滑坡基本信息 总被引:24,自引:2,他引:24
王治华 《中国地质灾害与防治学报》2004,15(1):94-101
在20多年滑坡遥感调查实践的基础上,文章介绍RS+GCPs获取滑坡基本信息的信息源、滑坡基本信息、遥感图像地面分辨率与最小可识别滑坡及不同比例尺滑坡遥感调查的关系.遥感图像是获取滑坡及其发育环境信息的最基本和最重要的信息源.目前用于滑坡调查的遥感数据可分为全色(panchromatic)、多光谱(Multispectral)和雷达(SAR)3类.据传感器又分为航摄和卫星两大类.获取地面控制点-GCPs信息源的方法主要有地形图采集GCPs、GPS现场实测GCPs以及用航片立体像对、卫星图像像对或雷达数据产生DEM.经过合格几何校正和地理位置配准的正射影像,才能作为获取数字滑坡基本信息的基础.滑坡基本信息就是滑坡要素及滑坡发育环境要素.一个发育完全的滑坡,一般具有下列要素滑坡体、滑坡周界、滑坡壁、滑坡台阶、滑坡舌、滑坡轴、滑坡鼓丘、拉张裂缝、剪切裂缝、扇形裂缝、鼓张裂缝、破裂缘、后缘洼地、滑动面、滑动带、滑坡床等.就滑坡解译而言,滑坡体和滑坡后壁两项为必要的最基本要素.产生滑坡的基本地质环境要素有①能产生滑动面的物质(地层、岩体、堆积),②使部分斜坡与山体分离的软弱结构面或带,③使与山体分离的部分斜坡可能向前运动的临空面.滑坡遥感调查还需收集及调查包括人类活动状况在内的触发因素资料.迄今,大多数滑坡遥感还是使用航片,航片的地面分辨率是由航摄胶片每毫米能区分出的最大线对数(Rh=可区分线对数/mm)、照相机镜头的分辨率及地物的反差比确定的.各类图像的最小可识别滑坡的规模-PRML除了与图像质量及地面分辨率有关以外,还与滑坡本身的类型、典型性以及与周围其它地物的反差比有关.就识别任一单要素而言,该要素在图像上应至少覆盖10 × 10个象元.由此,最小可识别的滑坡至少覆盖10×10×2个象元.不同地区不同类型滑坡的PRML是不同的.根据实践,至少覆盖1000个象元图像的滑坡体才有可能分析其各要素的特征,并进行定量分析,覆盖2000象元以上的滑坡才可能识别其要素的细部特征,所以不同比例尺滑坡遥感调查工作的详细程度不同,所需图像分辨率也不同. 相似文献
805.
The theory of physical interaction field by a differential geometrical approach combines the deformation field with the physical field (e.g., electromagnetic field), and derives a new tensorial relation between the deformation and the dielectric anisotropy of the crustal rocks. This relation can be applied to dielectric anisotropies of deformed natural rocks such as mylonites or gneisses. The dielectric anisotropies of mylonites are observed to increase as plastic strains of mylonites increase. Moreover, the derived tensorial relation can be linked to the electromagnetic potential field (deformational anomalies) in a deformed crust. A physico-geometrical consideration on this theory of physical interaction field is mathematically similar to ones on the theory of field in the Finsler space or on the concept of a unified gauge field. 相似文献
806.
Sheila Hones 《Geoforum》2004,35(5):549-552
This paper is a personal reflection on my participation in the panel “The Spaces of Critical Geography” at the ICGC in 2002, where my position as an European Americanist working in Asia was helpful in disrupting any tendency towards conflation of location, nationality, identity, and academic practice. These reflections focus on three topics: my interactions with various hegemonies and hierarchies; my relationship with the English language; and the contribution I believe critical geography can make to contemporary academic practice across the disciplines. 相似文献
807.
分析了传统边缘检测算法在多光谱影像应用中的局限性,提出了一种基于局部区域的光谱空间平均半径测度的边缘检测方法,该方法扩展了原有的单波段影像边缘检测的概念,将像元的灰度信息转化为光谱矢量,提高了检测的可靠性,并给出了多尺度边缘组合的算法。通过MAIS成像光谱仪对鄱阳湖30个波段数据试验,证明了此方法对边缘检测的有效性。 相似文献
808.
As the Mississippi River plays a major role in fulfilling various water demands in North America, accurate prediction of river flow and sediment transport in the basin is crucial for undertaking both short‐term emergency measures and long‐term management efforts. To this effect, the present study investigates the predictability of river flow and suspended sediment transport in the basin. As most of the existing approaches that link water discharge, suspended sediment concentration and suspended sediment load possess certain limitations (absence of consensus on linkages), this study employs an approach that presents predictions of a variable based on history of the variable alone. The approach, based on non‐linear determinism, involves: (1) reconstruction of single‐dimensional series in multi‐dimensional phase‐space for representing the underlying dynamics; and (2) use of the local approximation technique for prediction. For implementation, river flow and suspended sediment transport variables observed at the St. Louis (Missouri) station are studied. Specifically, daily water discharge, suspended sediment concentration and suspended sediment load data are analysed for their predictability and range, by making predictions from one day to ten days ahead. The results lead to the following conclusions: (1) extremely good one‐day ahead predictions are possible for all the series; (2) prediction accuracy decreases with increasing lead time for all the series, but the decrease is much more significant for suspended sediment concentration and suspended sediment load; and (3) the number of mechanisms dominantly governing the dynamics is three for each of the series. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
809.
LI Guowu YANG Guangming MA Zhengsheng SHI Nicheng XIONG Ming FAN Haifu SHENG Ganfu China University of Geosciences 《《地质学报》英文版》2005,79(3):325-331
1 Introduction Chevkinite groups can be assigned to the chevkinite-(Ce) subgroup and perrierite-(Ce) subgroup in accord with the angle β : β ≈ 100o for the chevkinite subgroup and β ≈ 113o for the perrierite subgroup. Chevkinite-(Ce), polykovite-(Ce) and Maoniupingite (new mineral No. 017 of 2003) belong to the former subgroup, while renjeite and matsubaraite belong to the latter group. As strontio-chevkinite is a Sr-analogue of perrierite, usually the natural chevkinite-(Ce) group min… 相似文献
810.