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1.
PatMoore 《成都信息工程学院学报》2002,17(4):289-299
尽管语法在交际教学法鼎盛时期一度遭到冷遇,但现在又重新被英语语言教学所接纳,作为一种新的语法教学方式,发现原则综合了传统归纳发和演绎法的长处,概述了发现原则的理论依据,指出发现原则旨在鼓励学习者积极参与而非被动接受,符合当前认知主义对二语学习的认识。 相似文献
2.
The analysis of the history of the management and distribution of electricity, water and sanitation networks in Santiago de Chile throws light on a problem which is central to thinking on the relationship between urban services management and territorial splintering: what is the impact of urban policy, in particular housing policy and urban planning, on access to services and on the potential levels of social segregation and institutional splintering of metropolises?The Chilean example is eminently anchored in its political and institutional history. We shall see, for example, that the authoritarian urban policy of the military government, associated with early liberal reform, enabled the improvement of access to networks in every municipality of the Greater Santiago area. However, this success, leading to the integration by urban services of a large territory, does not signify that networks remained neutral as regards the process of spatial segregation. Inversely, we can defend the theory that the presence of an integrated service was a necessary condition and a reinforcing factor of the process of urban spread and residential segregation. This paradoxical argument is a result of the ambivalent liberal network and urban policies of the military government. Urban expansion was largely sustained by the development of integrated infrastructures and universal services. The processes of liberalising land and urban services were mutually sustaining and provided the necessary conditions for the birth of an extremely intense movement of urban sprawl and segregation between 1985 and 2000. 相似文献
3.
This study takes cognizance of the fact that the TIOMIN (TIOMIN Resources Inc. of Canada) project has resulted in controversy over its handling of environmental issues and especially the Environmental Impact Assessment (EIA). The authors address many of the protracted issues that have slowed the development of the mining project in Kwale. The main emphasis is on the impacts of the mining and mineral separation processes on the environment, including the governing legislation, the role of consultation and public participation, and socioeconomic issues. In their public documents TIOMIN has specified neither the type of minerals it wants to extract from the area nor their chemical composition. It is well known, however that the titanium minerals and zircon targeted have impurities of iron, thorium and uranium. In the absence of an Environmental Management Plan, the effects of stockpiling radioactive wastes and other impurities that could possibly lead to environmental degradation in both the terrestrial and marine environments have not been publically addressed. The measures proposed to mitigate ecological damage as a result of the establishment of a minerals processing plant in the area seem inadequate. Pollution resulting from accidental spillage or breakage could have significant impact on marine life and residents living near the mining site. Other issues that have not been addressed satisfactorily pertain to the use of surface and underground water. The area already faces a huge water deficit and the calculations presented on aquifer recharge and stream flow rates do not indicate the large quantities of water that would be required in the mineral processing plant. The project, if approved in its present state, risks violation of international conventions. Furthermore, it could cause a conflict between Kenya and Tanzania in the event of an oil spill at the proposed ship loading facility at Shimoni. The proposed mining area includes the district's most fertile land, is home to many fisherfolk and is a major tourist destination. An analysis of the effects of this project on other available opportunities must be thoroughly understood to ascertain the economic and environmental benefits and costs of the mining venture. The proposed compensation rate of $1,000 per acre, for resettlement for example, appears to be grossly inadequate. Compensation should take into account family size and structure family assets and the cost of relocation. 相似文献
4.
首先对WebGIS的发展状况进行了分析,然后介绍了Web Services的工作原理,给出了面向Geo-Services的城市空间信息基础设施建设的结构模型,并依据该模型对北京市基础地理信息数据库集成项目进行了典型研究. 相似文献
5.
A multidisciplinary multi-scale framework for assessing vulnerabilities to global change 总被引:3,自引:0,他引:3
Marc J. Metzger Rik Leemans Dagmar Schrter 《International Journal of Applied Earth Observation and Geoinformation》2005,7(4):253-267
Terrestrial ecosystems provide a number of vital services for people and society, such as food, fibre, water resources, carbon sequestration, and recreation. The future capability of ecosystems to provide these services is determined by changes in socio-economic factors, land use, atmospheric composition, and climate. Most impact assessments do not quantify the vulnerability of ecosystems and ecosystem services under such environmental change. They cannot answer important policy-relevant questions such as 'Which are the main regions or sectors that are most vulnerable to global change?’ 'How do the vulnerabilities of two regions compare?’ 'Which scenario is the least harmful for a sector?’This paper describes a new approach to vulnerability assessment developed by the Advanced Terrestrial Ecosystem Analysis and Modelling (ATEAM) project. Different ecosystem models, covering biodiversity, agriculture, forestry, hydrology, and carbon sequestration are fed with the same Intergovernmental Panel on Climate Change (IPCC) scenarios based on the Special Report on Emissions Scenarios (SRES). Each model gives insights into specific ecosystems, as in traditional impact assessments. Moreover, by integrating the results in a vulnerability assessment, the policy-relevant questions listed above can also be addressed. A statistically derived European environmental stratification forms a key element in the vulnerability assessment. By linking it to other quantitative environmental stratifications, comparisons can be made using data from different assessments and spatial scales. 相似文献
6.
基于网格的空间信息模型与服务技术研究 总被引:12,自引:0,他引:12
空间信息基础设施是实现数字城市的核心与基础,现有的万维网已经不能满足空间信息访问与处理的需要。该文对以空间信息为核心和基础的数据网格——空间信息网格的基础理论及网格中的空间信息模型与服务技术:进行研究。提出了空间信息网格的若干关键技术及网格中的空间信息模型的特点与要求,并对空间信息网格服务进行了初步的探讨。 相似文献
7.
Application of discovery process models in estimating petroleum resources at the play level in China
Discovery process modeling has gained wide acceptance in the Chinese exploration community. In recent years, a variety of
discovery process models have been applied to the prediction of undiscovered petroleum resources at the play level in sedimentary
basins in China. However, challenging problems have been encountered, particularly when one method alone has been applied
to small plays in nonmarine sedimentary basins or in plays with an unusual order of discovery wells. This paper presents results
gotten by using the lognormal discovery process model of the Geological Survey of Canada and the geoanchored method for three
petroleum plays in basins with different geologic settings. Although the predicted shapes of the parentsize distributions
which use these two models, were not always similar, the expected values of the total resources and the number of fields (pools)
to be discovered are comparable. The combined use of two discovery process models in the same play compensates for the weaknesses
in one method compared with the other and vice versa. Thus, more reliable estimates are the result. 相似文献
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10.
玛纳斯县生态系统服务价值的动态评估 总被引:3,自引:1,他引:2
参考中国陆地生态系统单位面积生态服务价值表,对新疆玛纳斯县1988-2003 年的生态系统服务价值进行了动态评估.1988 年、1997 年和2003 年的生态系统服务价值分别为:58.98 亿元、49.76 亿元、50.22 亿元,1997 年的生态系统服务价值比1988 年减少了9.22 亿元,变化幅度为-15.6%;但2003年的生态系统服务价值比1997 年有所增长,增加了0.46 亿元,变化幅度为0.92%;1988-2003 年,该县生态系统服务价值总体减少了8.76亿元,变化幅度为-14.9%.同时,通过分析玛纳斯县各乡镇1988、1997 和2003 年生态系统服务价值的动态变化以及空间分布的差异,探讨了其生态系统服务价值动态变化的空间分异性. 相似文献