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101.
天津市海洋功能区划的比较研究   总被引:1,自引:0,他引:1  
利用对比分析法和GIS时空数据模型,研究2008年版天津市海洋功能区划相对2000年版的变化特征,分析区划分类体系和编制原则的变化,探讨了经济、社会、资源和环境等条件的变化,并分析区划空间结构和布局的变化特征。结果表明:(1)按照对人地关系疏密程度划分区划分类体系有利于识别开发、整治和保护区域界线;(2)兼容功能是解决当前区划体系存在主要问题的有效思路;(3)增殖区是天津市区划最大的变化来源,而围海造地区是主要的变化取向;(4)第二、三产业用海功能区呈现空间扩大趋势,近岸海域的增殖区呈现规模减小、空间布局转向较深海域趋势。  相似文献   
102.
江西丰城矿区障壁坝砂体内部构成及沉积模式   总被引:3,自引:0,他引:3  
江西丰城矿区上二叠统龙潭组狮子山段为障壁坝-湖体系沉积。该区障壁坝砂体包括前滨、临滨、入湖口潮道、涨潮三角洲、风暴冲越扇等成因相,这些成因相由10种构成单元组成。矿体内部可识别出五个等级界面,这些不同等级界面限定了不同级别沉积体的几何形态及其相互组合关系。  相似文献   
103.
本文在对贵州省织金地区含煤岩系进行成因地层分析的基础上,概括出了受潮汐作用影响的三角洲沉积体系的地方性沉积模式和聚煤特征。将三角洲体系划分为六种地貌单元:上三角洲平原、下三角洲平原、水下三角洲平原、边缘三角洲盆地、边缘三角洲潮汐平原及边缘三角洲沼泽平原。其中三角洲沼泽平原是最好的聚煤场所。  相似文献   
104.
分析和总结了"三规"关系及主要城市"三规合一"的实践工作。"三规合一"的发展可分为"两规"衔接和"三规"协调2个阶段。"三规"职责关系为:五年规划负责建设项目的类型和结构,城规负责建设项目的选址布局和规划设计,土规负责建设项目的用地规模落实;实施流程关系为:五年规划负责建设项目前期审核阶段的工作,城规负责建设项目的规划选址、设计施工阶段的工作,土规负责建设项目用地审批阶段的工作。现有"三规合一"工作可归纳为依托土规、依托城规和编制"三规合一"规划3种规划协调模式。  相似文献   
105.
ABSTRACT

The ground is one of the most highly variable of all engineering materials. As a result, geotechnical designs depend upon a site investigation to estimate the ability of the ground to perform acceptably. For example, when a shallow foundation is being proportioned to avoid a bearing capacity failure under a certain applied load, the frictional and cohesive properties of the ground under the foundation must first be estimated through a site investigation. Questions which arise are: How does the quality and intensity of the site investigation affect the design? Is more investigation cost effective? If the site is sampled at one location and the foundation placed at a different location, how does this mismatch affect the target design and the reliability of the final foundation? By modelling the ground as a spatially variable material, questions such as the above can be investigated through Monte Carlo simulation and sometimes theoretical probabilistic models. Using such tools, this paper looks specifically at how the intensity (frequency and spatial distribution) of a site sampling plan, and how the samples are used, affects the understanding of the ground properties under a foundation. Interestingly, it is found that removing the sample mean outperforms removing the best linear unbiased estimate (BLUE) when the actual field correlation length is small but the BLUE correlation length is assumed equal to the field size. Recommendations are made regarding number of samples and the type of trend to best characterise the field.

Abbreviations: BLUE: best linear unbiased estimate; MCS: Monte Carlo simulation; LAS: local average subdivision  相似文献   
106.
《The Cartographic journal》2013,50(3):274-286
Abstract

John Wood, the 19th-century urban cartographer, surveyed almost 150 towns spread widely across Great Britain. His detailed large-scale plans are an astounding achievement. In light of this, two questions are posed: did he have a strategy that guided the places which he surveyed; and how did he pay for his work, given that so few copies of his plans appear to have been produced for sale – or at least to have survived.  相似文献   
107.
根据高职土建类建筑工程专业的人才培养目标 ,结合测量新技术和人才市场的需求 ,提出了《建筑工程测量》课程改革与建设的办法与措施 ,符合教学认知规律 ,利于改进教学效果和提高教学质量。  相似文献   
108.
Climate change mitigation is a wicked problem that cuts horizontally across sectors and vertically across levels of government. To address it effectively, governments around the world, in particular in the EU, have developed several generations of multi-sectoral national mitigation strategies (NMS) since the early 1990s. Although NMS became the main effort to systematically coordinate mitigation policies, few works have studied them comparatively so far. The present article fills this gap by analysing how the EU-15 group of countries operationalized climate protection through NMS. First, we introduce the three roles policy strategies usually aim to fulfil: besides being policy documents they also represent governance processes (supposed to coordinate sectoral implementation), and capacity-building efforts. Empirically, we then explore the rationale, origins and prevalence of NMS. Subsequently, we characterize them as policy documents (with regards to their contents and structures) and as governance processes that address capacity building only implicitly. Based on existing assessments we finally review some performance indications of NMS. We find that in particular second- and third-generation NMS aimed to take their governance function seriously but resembled ‘lacklustre bookkeeping' of emissions, targets and mitigation options. Instead of approximating NMS towards their obviously overcharging governance function, we suggest to recalibrate them towards their communication and capacity-building function in a way that goes beyond bookkeeping.

Policy relevance

The present article shows that NMS fail to effectively govern climate change mitigation across a broad range of sectoral policy domains. Since most European countries have adopted not one but up to three generations of NMS since the 1990s, this finding is highly relevant for them – and for all others aiming to adopt similarly broad strategies. Instead of piling one strategy on top of another irrespective of their implementation, and instead of abolishing mitigation strategies altogether, we recommend recalibrating them towards what they can realistically accomplish: effective communication and capacity building so that NMS can advance from lacklustre bookkeeping to actively promoting a government-wide climate change mitigation vision. The article can help governments to realise that renewing integrated strategies such as NMS without overhauling them comes close to flogging a dead horse.  相似文献   

109.
以建筑平面图为数据源,提出了一种自动生成室内地图空间数据的方法。首先,结合室内地图空间数据的需求分析了建筑平面图的基本特征,提出了墙段、邻接节点和相邻墙段的概念,并在此基础上建立了自动生成室内地图空间数据的基本流程。然后,根据与柱子相交墙线的相邻关系,建立了与柱子关联墙体连通性的恢复方法;结合渐进扩张与图形推理判断门窗两侧墙体符号局部特征的类型,通过修正门窗外接矩形,建立了与门窗关联墙体连通性的恢复方法和将门窗转换为室内地图点状要素的方法。最后,基于相邻墙段中心线的几何关系,建立了墙体中线的提取算法。以某展览馆的建筑平面图为例进行试验,结果表明本文的方法针对多种复杂情况均有较好的适用性,有效实现了室内地图空间数据的自动生成。  相似文献   
110.
针对地下河流相储层内部建筑结构分析难度大、非均质性突出的问题,在岩芯、露头、钻井、测井资料分析的基础上,以胜坨油田二区沙二段3砂层组(胜二区S32)辫状河沉积体为例,运用Miall的结构要素分析法,进行层次界面解剖、岩相类型和建筑结构要素的划分,提取相应测井曲线特征参数,建立有效的结构要素定量模糊识别模型,并编成软件,对研究区进行了实际资料处理,结果与地质专家解释结果相当吻合,最后建立了储层建筑结构展布模型,精细表征了砂体间的接触方式和连通程度,为进行精确的储层预测和剩余油挖潜提供了地质依据。  相似文献   
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