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91.
在对中国西部的区域划分进行界定并阐述中国西部区域特征的基础上,对中国西部的开发进行了历史回顾,并对中国西部开发的历史背景和现实基础、中国西部开发的优势和制约条件进行分析,最后提出了中国西部开发的发展战略和政策措施. 相似文献
92.
构建区域创新政策评价的理论框架,在宏观知识生产函数中引入信息化作为创新技术进步的替代变量,基于DEA与Malmquist指数,用全要素生产率指数存量来衡量区域创新政策。并以省际高技术产业为例进行了实证,研究结果表明:区域创新政策的特征和评价维度决定评价的多样性,基于政策效果与政策交互作用的区域创新政策评价具有重要意义;区域创新政策总体上处于稳步提高阶段,较低地区以西部中部地区为主;区域创新政策测度模型系统性较好,其检验方法有待进一步深化;采用政府研发经费投入作为区域创新政策的替代变量值得商榷。 相似文献
93.
核废物地质处置中热-水-应力耦合对迁移影响的三维有限元模拟 总被引:1,自引:0,他引:1
将所建立的热-水-应力-迁移耦合模型及开发的有限元程序,由二维分析拓展到三维分析,并从方法论研究的角度,以一个简单的核废物地质处置模型为算例,进行热-水-应力-迁移耦合过程的三维数值模拟,考察了近场的温度、饱和度、核素浓度、孔隙水压力、位移、正应力、流速等的分布与变化,认为计算结果符合规律,得出了若干结论:为了精确地模拟放射性核素迁移,就必须将温度场、渗流场、应力场和核素浓度场进行耦合分析;核废物埋存若干年后将在处置孔壁附近产生较高的压应力;缓冲层内各点的核素浓度达到相对稳定的时间要比温度和饱和度达到相对稳定的时间长得多。 相似文献
94.
50年来我国化工地质找矿及相关的研究工作都取得了显著的成绩,虽然我国化工矿产种类较齐全,但人均占有资源量偏低,保证程度与需求相比尚有不同程度的差距。化工地质工作今后应统筹规划,突出重点;发挥优势,确保化工;面向市场,拓宽领域,狠抓基础,强化竟争;严格质量,规范管理;科技创新,加强装备;突出效益,转变机制;争取政策,多元投入。在化工地质队伍推行“三新、两高、两精”的运行机制。为确保“十五”期间工作部署能顺利实施,需要国家在宏观层面上给子相应的政策支持。 相似文献
95.
Gerardo Bocco Angel Priego Helena Cotler 《Singapore journal of tropical geography》2010,31(2):215-223
In recent years, physical geography in Mexico has contributed to the enterprise of geographical science by integrating with fields of study closely related to topics of sustainable development. This paper outlines the contribution of the discipline to environmental public policy development, particularly ecological land use planning and integrated watershed management. In terms of applications, physical geography appears to have reached a stage of maturity in Mexico. However, it must offer a stronger leadership in areas such as ecoregional analysis (in an integrated fashion, and not only from the biological‐ecological perspective) and regional vulnerability to global change processes. An excellent opportunity exists for scientists and decision makers to develop a common agenda. 相似文献
96.
97.
Geoff Kelly 《Geoforum》2007,38(2):326-338
The development of renewable energy sources is of prime interest to many countries seeking to pursue greenhouse gas emission reduction obligations. The increased use of renewables offers the possibility of not only contributing to emission reduction, but at the same time improving energy supply diversity and security, and developing employment and business in related supply industries. Two main mechanisms are in common use, one a quota (quantity) instrument often associated with tradable certificates, and the other a prescribed pricing mechanism. This paper considers the renewable energy development strategies of three countries (the UK, Australia, and New Zealand) all using a variant of the quota/certificate approach as the central instrument in their programs. The regulatory frameworks defining the application of the certificate systems differ notably, and the likely differing outcomes suggest that these regulatory settings may be at least as important as the selection of the basic policy instrument, in determining the overall success of programs of this nature. 相似文献
98.
99.
Iain Docherty 《Area》2001,33(3):321-328
This paper presents an analysis of Transport 2010, the government's ten-year plan for transport. It develops discussions held by members of the RGS-IBG's Transport Geography Research Group (TGRG) in September 2000. It is argued that the plan marks something of a return to previous policies designed to accommodate increasing mobility. 相似文献
100.
Matej Cebecauer Konštantín Rosina Ľuboš Buzna 《International journal of geographical information science》2016,30(4):765-784
Public service systems, such as emergency health care, police or fire brigades, are critical for day-to-day functioning of the society. To design and operate these systems efficiently much data needs to be collected and properly utilised. Here, we use the OpenStreetMap (OSM) data to model the demand points (DPs), which approximate the geographical location of customers, and the road network, which is used to access or distribute services. We consider all inhabitants as customers, and therefore to estimate the demand, we use the available population grids. People are changing their location in the course of the day and thus the demand for services is changing accordingly. In this paper, we investigate how the used demand estimate affects the optimal design of a public service system. We calculate and compare efficient designs corresponding to two demand models, a night-time demand model when the majority of inhabitants rest at home and the demand model derived from the 24-hour average of the population density. We propose a simple measure to quantify the differences between population grids and we estimate how the size of differences affects the optimal structure of a public service system. Our analyses reveal that the efficiency of the service system is not only dependent on the placement strategy, but an inappropriate demand model has significant effects when designing a system as well as when evaluating its efficiency. 相似文献