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231.
叠前深度偏移述评   总被引:4,自引:2,他引:4  
叠前深度偏移是理想的改善复杂地区和强横向速度变化的地震资料成像技术,笔者就4种典型叠前深度偏移方法的理论基础与技术特点,存在的问题及国内外最新进展进行了讨论.  相似文献   
232.
天山北麓玛纳斯河流域山问洼地位于低山丘陵区山前坳陷带的南部,该区褶皱、断裂、近NS向次级张性断裂与平移构造以及山间洼地的第四系沉积物发育.山区地表水流经该段入渗,加之南部中山区的侧向补给形成山间洼地地下水库.正确认识玛纳斯河流域山间洼地地下水库的形成机理并对其进行合理的开发利用,对解决玛纳斯河流域季节性缺水及枯水年缺水有重要意义.笔应用构造及地表水由山区水站至山口渠首站实测流量损失的研究成果,揭示了玛纳斯河流域山间洼地地下水库的形成及调蓄作用,并概算了补给量,为今后开发利用山间洼地地下水库水资源提供了依据.  相似文献   
233.
环境岩土工程研究现状与展望   总被引:5,自引:0,他引:5  
苏燕  周健 《岩土力学》2004,25(9):1510-1514
小环境岩土工程问题已经逐渐成为环境岩土工程研究的热点问题。笔者对环境岩土工程的研究内容作了简要介绍,简述了国内外在小环境岩土工程研究方面的现状和进展,重点就垃圾卫生填埋问题,特别是沿海软土地区垃圾堆埋场的设计等问题进行了讨论,对国内环境岩土工程的发展提出了一些看法。  相似文献   
234.
结合西部地区某深埋长大公路隧道信息化施工 ,对深埋长隧地应力演化及围岩应力位移进行了弹塑性有限元数值模拟研究。研究结果表明 ,隧道轴线现代地应力状况与隧道埋深、地层岩性及构造发育程度有关 ,最大地应力为40 0MPa左右 ;隧道周边围岩应力在曲边墙底部最大 ,约 3 8 0MPa ,隧道开挖引起的围岩应力影响范围约 2 5 0m ;隧道水平收敛和拱顶下沉位移与隧道埋深近于成直线关系。这些研究结果为深埋长隧信息化设计和施工以及围岩稳定性分析提供了科学依据。  相似文献   
235.
李军政 《陕西地质》2004,22(1):93-100
地理信息系统是国家信息资源的重要组成部分。地理信息技术经过20多年的飞速发展,已经渗透到社会各个方面,促使人们生产、生活方式发生深刻变化。我国地理信息系统(GIS)技术正在向信息化方向发展,并正在逐步成为面向21世纪的支柱产业一信息产业的重要组成部分。国际GIS技术的发展趋势,主要体现在两个方面,一是综合,二是分化。从空间信息处理的角度看,可将GIS的发展分为空间信息的管理、分析、模拟和调控四个阶段。GIS技术的应用表现在一是面向大型项目,二是面向公众。  相似文献   
236.
关中盆地水资源可持续开发利用对策研究--以渭南市为例   总被引:4,自引:0,他引:4  
以关中盆地东部的渭南市为例,概述了水资源的分布特征及其开发利用现状。认为水资源开发利用中存在水资源浪费严重,重复利用率低;行政区块限制,水资源调配不够;不合理开采地下水,出现负环境效应;地下水人工调控力度不够,不能有效的促进生态环境良性循环;对地下水资源的研究、规划和管理滞后等五个方面的主要问题。针对存在的主要问题,提出了六项水资源可持续开发利用对策,包括节水对策、开源对策、改水对策、调水对策、增补对策以及管理对策。  相似文献   
237.
The devolution and regionalisation of political and administrative structures following the election of New Labour in 1997 have changed the nature of the state and territorial development and governance in the UK. A regional and sub-national tier has opened up within the existing multi-layered governance system operating at the supra-national, national and local scales. This ‘new institutional space’ is increasingly open to the participation of social institutions--including trade unions--in economic and social governance. Drawing upon empirical analysis of the experience of the Northern Trade Union Congress (NTUC) in the North East region of England, the paper argues that the NTUC--in contrast to its national organisation--is beginning to engage with the emergent institutional structures but its role is inhibited by the centralised strategy and structure of the TUC nationally, its own need for upgrading, capacity building and greater financial resources and the interaction between the North East’s particular legacy of tripartite corporatism and the more pluralist modes of regional development governance emerging in the English regions. Unless such issues are addressed regional trade union centres--such as the NTUC--risk remaining relatively junior partners in the emergent regional governance structures.  相似文献   
238.
Urban land transformation for pro-poor economies   总被引:1,自引:0,他引:1  
Solomon Benjamin 《Geoforum》2004,35(2):177-187
The transformation of land into a setting for clustering local economies can become an important cornerstone of poverty policy. This transformation has several functional aspects, which in turn have important institutional and political aspects. Underlying both the functional and institutional factors is the role of local government and local democracy. Such a conceptualization puts to center stage several paradoxes: A terrain that seems “slum-like” turns out to be highly productive and employment generating. Complex tenure forms and mixed land use seen as “unplanned” turn out to be pre-requisites for economic development. There are institutional paradoxes that contrast efforts at “transparency” and managerial “best practices”. Here, the messiness of local bureaucracies in municipal government turns out to be critical for poor groups to influence interventions in their favor. Influencing the public process may be more effective in stealth-like ways rather taking a more visible approach. Most fundamentally these issues remind us that the potential of cities to reinforce or reduce poverty moved far beyond projects and programs and the normative frameworks used by planners and administrators. Instead, it is the transformative process of turning land into economic settings that might be at the center stage. This is a stage where poor groups are the central actors who stealth-like draw on complex alliances across ethnic and class lines to shapes cities in their interests.  相似文献   
239.
Liisa Rohweder 《GeoJournal》2004,60(2):175-181
Environmental education in business school context has a significant effect on the way companies view environmental problems. Business schools train the future decision makers who can, with their own attitudes and practical actions, influence the contribution of business to the process of ecologically sustainable development. However, several studies show that no systematic thinking has been undertaken within business education as to what the educational prerequisites of the process of ecologically sustainable development are. In this article, I will firstly analyze by means of environmental education how business polytechnics in Finland have taken into consideration ecologically sustainable development. Secondly, I will raise the starting points for the development of the implementation of environmental education as part of the business schools▪ educational plans. Integrating environmental education into the vocational courses is identified as being one of the most effective ways of increasing the effectiveness of environmental education. Thirdly, the emphasis is on identification of barriers of integrating environmental education into the educational plans of business polytechnics. Theoretically, the article is attached to the objectives and learning concepts of environmental education and to educational planning theory in general. The empirical data are based on interviews I conducted 1999–2000 in all Finnish polytechnics offering business education. My article increases theoretical and practical understanding of how environmental education should be implemented in business education and how the current situation could be developed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
240.
The British city centre has been the focus of dynamic housing development and repopulation strategies as a key dimension of the government's urban renaissance programme. Through large scale interview surveys in the provincial city centres of Bristol and Swansea, this paper explores the positive and negative features of city centre living, and how these vary amongst a range of social and physical characteristics. The findings suggest that the practical and mundane attractions of city centre living are more important than the more widely publicised lifestyle and cultural attractions of the city centre commonly emphasised in the gentrification literature. Moreover, the research points to differences in attitudes between age groups, with younger adults placing greater value on the range of social and cultural activities in the city centre, whilst older people express high levels of satisfaction with the attractiveness of the environment. A number of policy implications emerge to encourage inclusive marketing strategies within the continued urban renaissance, particularly to challenge the negative perceptions and promote the varied attractions of city centre living to a mix of social groups.  相似文献   
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