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231.
《Geoforum》2017
This research is located at the intersection of three canals in periurban Gurugram. Two of these canals were built to provide water for the growing city of Gurugram and one of them carries the wastewater of the city back to the villages. These canals cut through periurban villages that are excluded in principle from taking benefit of these canals. They are meant to be at their receiving end, as recipients of these waters. The paper, using a socio-technical lens, explores the mixed impacts of these canals on the villages through which they traverse. The paper further describes the strategies that periurban communities devise to circumvent the situation of exclusion. Using a qualitative, ethnographic research design, the paper describes the socio-technical mediation of periurban water insecurity, focusing on the mix of technologies and institutions that spring up around these canals that shape the periurban water users’ access to water. The paper concludes that approaches for promoting community resilience and periurban water security need to start from an understanding of the strategies devised by periurban communities to improve their access to water. In the larger discourse on building community resilience in the face of urbanization and climate change it is important to pay attention to local norms of cooperation that enable periurban communities to access water, rather than start from a premise that water insecurity caused by urbanization and climate change will lead to conflicts or necessitate capacity-building to promote avoid conflict and promote cooperation. 相似文献
232.
R. S. Stobie 《Astrophysics and Space Science》1995,230(1-2):9-15
Because of its geographical location and (astronomically) excellent climate South Africa can make an unique contribution to international astronomical research. An assessment of recent developments in telescope technology has shown that an advanced technology telescope of 4m-class can be constructed which will out-perform most existing 4m-class telescopes. Detailed consideration is given to the construction of such a telescope for optical/infrared astronomy, the new science that this will enable and the selection of a site of sufficiently good quality to justify the erection of such a telescope. If a telescope of this nature is sited in southern Africa it would provide the premier astronomical facility in Africa for decades to come. 相似文献
233.
Liang Shuangyou 《时间频率学报》1995,(1)
根据我国同步广播卫星的现状,本文提出在不专门占用卫星信道的情况下,保留现有的CCTV中的时间信号,并将卫星轨道参数以及其它参数插入到CCTV信号中去的技术问题以及控制方法,完成同步卫星的高精度授时工作。 相似文献
234.
《The Professional geographer》1985,37(2):226-262
Book Reviewed in this article: The City in Cultural Context . John Agnew, John Mercer, David Sopher, eds. Soils and Geomorphology Peter W. Birkeland. Urbanization and Settlement Systems, International Perspectives . L. S. Bourne, R. Sinclair, and K. Dziewoński. eds. An Introduction to Urban Historical Geography . Harold Carter. Overshoot, The Ecological Basis of Revolutionary Change . William J. Catton, Jr. Rivers of the World . Eberhard Czaya. Jewish Communities in Frontier Societies: Argentina, Australia and South Africa . Daniel J. Elazar with Peter Medding. Color in Public Spaces: Toward a Communication-Based Theory of the Urban Built Environment. Kenneth E. Foote. Spatial Statistics and Models. Gary L. Gaile and Cort J. Willmott, eds. Mega-Geomorphology. Rita Gardner and Helen Scoging, eds. Technological Change and Regional Development. Gillespie, ed. The Arid Lands: Their Use and Abuse. R. L. Heathcote. The Location of Industry in Britain. A. G. Hoare. Groundwater as a Geomorphic Agent . R. G. LaFleur, ed. Rural Public Services: International Comparisons. Richard E. Lonsdale and Gyorgy Enyedi, eds. Saving Water in a Desert City. William E. Martin, Helen M. Ingram, Nancy K. Laney, and Adrian H. Griffin. Water Resources: Distribution, Use and Management. John R. Mather. Transnationals and the Third World: The Struggle for Culture. Armand Mattelart. South Hadley, MA: USGS Digital Cartographic Data Standards. R. B. McEwen, R. E. Witmer, and B. S. Ramey, eds. The Ecosystem Concept in Anthropology. Emilio F. Moran, ed. Boulder, CO: Women, Men, and the International Division of Labor. June Nash and Maria Patricia Fernandez-Kelly, eds. Nuclear Power: Assessing and Managing Hazardous Technology. Martin J. Pasqualetti and K. David Pijawka, eds. Mary Somerville and the Cultivation of Science 1815-1840. Elizabeth Chalmers Patterson. An Introduction to Coastal Geomorphology. John Pethick. Late Quaternary Environments of the United States , Vol. 1, The Late Pleistocene. Stephen C. Porter, ed. Planning and Ecology. R. D. Roberts and T. M. Roberts, eds. Regionalism and the Pacific Northwest. William G. Robbins, Robert J. Frank, and Richard E. Ross, eds. Environment and Health. Anthony J. Rowland and Paul Cooper. Sunbelt/Snowbelt: Urban Development and Regional Restructuring. Larry Sawers and William K. Tabb, eds. The Bad Earth. Environmental Degradation in China. Vaclav Smil. Armonk, NY: Voyage into Substance: Art, Science, Nature, and the Illustrated Travel Account, 1760–1840. Barbara Maria Stafford. The Institute of British Geographers: The First Fifty Years. Robert W. Steel. Visions of the Past. Christopher Taylor and Richard Muir. Glacial Lake Agassiz. J. T. Teller and Lee Clayton, eds. The Tule Breakers: The Story of the California Dredge. John Thompson and Edward A. Dutra. The Balkan City 1400–1900. Nikolai Todorov. Explanation, Prediction and Planning: the Lowry model. Michael J. Webber. Mercedes Reales: Hispanic Land Grants of the Upper Rio Grande Region. Victor Westphall. The World Atlas of Revolutions. Andrew J. M. Wheatcroft. The West European City, A Social Geography. Paul White. Urban Elites and Mass Transportation. J. Allen Whitt. Princeton, NJ: Urban Life In Contemporary China. Martin King Whyte and William L. Parish. The Demand for Energy in the Soviet Union. David Wilson. London and Canberra: Rethinking Geographical Inquiry. J. David Wood, ed. 相似文献
235.
236.
国土资源遥感技术进展与展望 总被引:2,自引:2,他引:2
本文简要回顾了中国国土资源航空物探遥感中心的遥感技术发展历程,着重介绍新一轮国土资源大调查实施以来的主要技术进展与应用成果,并对今后我国国土资源遥感技术的发展方向进行分析。 相似文献
237.
Review on researchesof nitrous oxide inthe Southern Oceanand relative new technologies 总被引:1,自引:0,他引:1
Nitrous oxide is an important greenhouse gas,which has a long lifetime of about 120 years and has a 310 times greenhouse effect than CO2. Since the industrial revolution, the atmospheric N2O concentration has increased significantly by 20%. Ocean is a net source, about 1/3 of total oceanic souce. Southern Ocean is an important part of the global ocean system, has a unique hydrological characteristics. So far it is regarded as a significant natural source to the global N2O flux according to the model studies. However,the field work is very limit, due to the fierce in situ conditions. The importance of N2O reseaches of Southern Ocean, progresses of nitrous oxide researches, especially new technologies applied to underway N2O measurements in the Southern Ocean are reviewed. The advance of field, model studies and their problems or uncertainties that need to be resolved are also discussed. The using of stable isotope methods will provide powerful tools for marine N2O mechanism. Development of high precision monitoring technology is generally the driving force of future research. Developing techniques of laser spectroscopy in marine N2O studies and measurment of N2O in sea ice will provide powerful tools to differeciate the N2O source sink characteristic, constrain their budget and formation mechanism in region such as Southern Ocean. 相似文献
238.
北斗地基增强系统是推广高精度“北斗+”应用的重要基础设施。本文首次研究千寻位置、六分科技及中国移动3家覆盖全国的北斗地基增强系统的定位服务性能,通过对2021-07-21~22采集的2次8~9 h观测数据进行分析,得到以下结论: 1) 千寻位置和中国移动的官方推荐挂载点支持BDS-2三频信号和BDS-3双频信号(B1I、B3I),六分科技支持BDS-2和BDS-3双频信号(B1I、B3I); 2) 3家北斗地基增强系统都能提供100%的北斗数据完整率; 3) 静态基线结果表明,3家北斗地基增强系统虚拟基站组成的闭合环相对误差均小于2×10-6; 4) 单历元RTK解算结果表明,3家北斗地基增强系统均能够提供水平向优于3 mm、垂直向优于9 mm的内符合精度,但不同北斗地基增强系统之间存在cm~dm级的定位结果偏差,因此不建议在RTK作业时使用不同的北斗地基增强系统。 相似文献
239.
2011年,发达国家受主权债务危机影响,新兴经济体通货膨胀压力上升,各国经济增速普遍下滑在这样的大环境下,我国非开挖行业仍取得了骄人的成绩。本文首先概述了2011年在我国非开挖行业影响较大的重大事件,然后较详细地介绍了中关两国非开挖市场的调查情况,包括中美水平定向钻机情况和美国市政管线建设投资情况,最后对未来我国非开挖行业的发展趋势进行了预测。 相似文献
240.