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41.
我国省市级大地水准面精化的现状及技术模式 总被引:46,自引:5,他引:41
高精度局部大地水准面将为测绘学、地球物理、地球动力学及海洋学等相关学科的发展和应用提供重要的基础地球空间信息。GPS技术结合高精度大地水准面模型可应用于取代传统的高程测量(如三角高程测量和低等级水准测量),这是当前精化我国省市级大地水准面在测绘领域的主要目的之一。在总结和分析我国目前省市级大地水准面精化的现状、技术模式及特点的基础上,提出了今后精化我国省市级大地水准面的若干建议。 相似文献
42.
Bioreactor landfill 总被引:2,自引:0,他引:2
WANGHao XINGKai AnthonyAdzomani 《东北亚地学研究》2004,7(1):85-91
Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In contrast to the conventional landfill, this paper introduces a new technique named bioreactor landfill (BL). Mechanisms, operation conditions as well as the advantages and disadvantages of BL are also discussed in this paper. 相似文献
43.
城市垃圾的生物处理技术 总被引:1,自引:0,他引:1
生物技术是实现城市垃圾无害化和资源化的一种有效手段。重点阐述了城市垃圾生物处趣的基本原理及3种主要的生物处理方法,简要介绍了城市垃圾生物处理方法中的一些新技术及发展趋势,为寻找适合我国国情的垃圾处理技术提供一些参考。 相似文献
44.
Following the population expansion, there is a growing threat brought by municipal solid waste (MSW) against environment and human health. Sanitary landfill is the most important method of MSW disposal in China. In contrast to the conventional landfill, this paper introduces a new technique named bioreactor landfill (BL). Mechanisms, operation conditions as well as the advantages and disadvantages of BL are also discussed in this paper. 相似文献
45.
合肥市生活垃圾处理项目是安徽省内规模最大的垃圾处理填埋场,工程区地质条件复杂,防渗设计要求严苛,经过工程地质水文地质测绘、钻(静)探、取样测试、地球物理勘探、原位测试、水文地质试验等综合手段勘察,取得了科学准确的参数,对建筑物的地基持力层的选择、设计参数、防渗处理等提出了经济合理的结论和建议,为优化设计、节省投资、安全施工奠定了基础,取得了良好的经济效益及社会效益,同时也积累了同类型项目在花岗岩地区复杂地质条件下的水文地质工程地质勘察经验. 相似文献
46.
基于城市固体废弃物(MSW)的降解及土力学特征,在应力降解模型、等向压缩特性和邓肯-张模型的理论基础上,建立了一个能够描述MSW应力和降解耦合作用的全量非线性本构模型。给出了不同应力状态下单元体体积和轴向变形随时间变化的数学表达,同时给出了所有参数的确定方法。采用该模型对不同龄期和不同围压条件下填埋场现场试样的三轴CD应力-应变曲线以及室内长期一维降解压缩试验进行了模拟。结果表明,模型概念合理、参数明确,能够较全面地描述不同降解龄期垃圾的本构关系,可用于分析填埋场的长期变形。 相似文献
47.
A clear understanding of the relationship between development patterns and municipal expenditures is complicated by how one chooses to quantify these patterns. Extant literature often employs a single density measure to capture the low-density nature of sprawl. While density provides an intuitive link to economies of scale and congestion costs, it fails to capture other spatial characteristics of sprawl related to centrality, connectedness, and mixed use that may influence municipal expenditures according to Smart Growth and New Urbanism advocates. This study uses Massachusetts orthoimagery data to construct multidimensional measures of residential and commercial land use patterns. Municipal expenditures associated with public works, fire, and police are regressed on multidimensional measures of land use as well as a number of demand controls. Findings indicate that economies and diseconomies do exist with respect to the multidimensional metrics considered. Support is mixed for development patterns emphasized by Smart Growth and New Urbanism advocates. 相似文献
48.
《Urban geography》2013,34(4):568-588
The incorporation of a city is a complex geographic event, yet the geography of newly incorporated municipalities (NIM) has been understudied. This paper first explores the highly uneven spatial distribution of NIMs in the United States, arguing that one potential explanation for the underlying geographic concentration of NIMs to a select few states may lie with the varied annexation standards of each state. However, it is also argued that the concentration of NIMs in particular "hotspots" within specific states suggests that something more is at play, and the localized clustering effect seems to be stimulated by a process of knowledge spillover and social networks of learning. Second, little research has been conducted that empirically compares the socio-economic characteristics of NIMs to a set of nearby cohort cities. It is argued that while race, income, population size, and population density are key differentiating variables between NIMs and cohort cites, nuanced differences and similarities exist that make it difficult to support sweeping generalizations. 相似文献
49.
Scholarly literature on newly incorporated municipalities (nims ) often focuses on why nims form. Instead of asking why nims formed, however, we ask why nims stopped forming. We first establish a temporal context for nims from 1950 to 2010, revealing an 86.2 percent decline in nim formation. The decline, triggered by stricter laws, smaller annexations, declining suburbanization, and boundary ossification, has profound implications for metropolitan fragmentation and public choice. We then establish a state‐level spatial context, revealing distinct high‐nim , low‐nim , and flux states due to boundary ossification, growth, and state/regional policy stimuli such as consolidation efforts, grants, and growth management provisions. 相似文献
50.
Recent years have seen a rapid rise in the political saliency of the ever growing volumes of municipal waste produced in the UK. In this paper, we examine how one particular part of the municipal waste stream – biodegradable waste – has come under the policy spotlight. As targets to divert biodegradable waste from landfill under the Landfill Directive come into force, the need to focus explicitly on recovering value from biodegradable materials has risen up national and local policy agendas, not least with the introduction of the Landfill Allowance Trading Scheme. Accompanying this new rationality for managing waste has been a suite of different policy interventions. In this paper we examine the impact of the changing nature of municipal waste policy and the ways in which it has sought to rework the disposal and collection of biodegradable waste. We argue that the predominantly technical framing and instrumental rationality of these interventions does not sufficiently challenge entrenched understandings regarding the boundaries between public and private responsibility for waste, and thus short-circuits their capacity to engage with everyday community/individual waste practices. In conclusion, we suggest that, in order to move waste management towards sustainability, there is a need both to engage with the institutional and infrastructural dimensions of the systems of provision within which waste management occurs, and to take seriously the everyday contexts within which making waste is practiced. 相似文献