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101.
介绍了平面控制网精度评估的原理,并以佛山市某体育馆变形观测平面控制网设计方案之一为例,对控制网的布设要求、设计数据的组织方法、用MATLAB语言实现精度评估的方法做了详细阐述。就平面控制测量优化设计的实现方法做了一些新尝试,对于高精度变形观测平面控制网的优化设计具有一定的参考价值。  相似文献   
102.
Plural valuation is about eliciting the diverse values of nature articulated by different stakeholders in order to inform decision making and thus achieve more equitable and sustainable outcomes. We explore what approaches align with plural valuation on the ground, as well as how different social-ecological contexts play a role in translating plural valuation into decisions and outcomes. Based on a co-constructed analytical approach relying on empirical information from ten cases from the Global South, we find that plural valuation contributes to equitable and sustainable outcomes if the valuation process: 1) is based on participatory value elicitation approaches; 2) is framed with a clear action-oriented purpose; 3) provides space for marginalized stakeholders to articulate their values in ways that can be included in decisions; 4) is used as a tool to identify and help reconcile different cognitive models about human-nature relations; and 5) fosters open communication and collaboration among stakeholders. We also find that power asymmetries can hinder plural valuation. As interest and support for undertaking plural valuation grows, a deeper understanding is needed regarding how it can be adapted to different purposes, approaches, and social-ecological contexts in order to contribute to social equity and sustainability.  相似文献   
103.
This paper uses the Kristrom (logit) spike model to analyse contingent valuation (payment card) data from a study of 2180 domestic and international visitors taking reef trips to the Northern section of the Great Barrier Reef. It investigates: (a) their willingness to pay for a “100% guaranteed sighting” of several different marine species; and (b) the sensitivity of final estimates to various methodological issues. It finds that final estimates are particularly sensitive to questionnaire design, but that the ranking of species (from most to least ‘valued’) is robust across a range of methodological specifications. The most valued groups of species were (in order): whales and dolphins; sharks and rays; ‘variety’; marine turtles; and finally large fish. Evidently, whale watching is not the only potentially lucrative source of tourism revenue; other marine species may be similarly appealing. These potential revenues need to be considered when making decisions about whether or not to conserve marine species.  相似文献   
104.
通过对8种因素、77种状态的信息量计算,得出研究区稳定性信息的权值。在取得128个预测单元的信息量预测值之后,划分出53个活动单元和较活动单元,其中12个为新预测的不稳定区。与仪器观测结果比较,一些新预测区的不稳定性得到证实。研究表明,信息量法对评价工程高边坡稳定性,特别是消除工程隐患具有重要意义。  相似文献   
105.
The Irish marine economy and regional development   总被引:1,自引:0,他引:1  
The economic impact of the marine economy is poorly understood at both national and regional levels in Ireland. A recent paper estimated the national level economic value of the sector for Ireland. This paper presents a follow up analysis of the Irish marine sector at the regional level for 2007. The paper examines the impact of the marine sector in addressing regional disparities in Ireland, and the key marine sectors that drive regional economic performance within the marine sector. The analysis finds that in absolute values Dublin and the South West provide the highest levels of marine GVA; however, as a percentage of regional GVA, the marine sector is more important in the West and South West region. In terms of employment, the West and South-West provide the highest levels of marine employment, and this relationship is maintained when one examines marine employment as a percentage of regional employment. Finally, productivity rates for the sector were highest in the Dublin region. However, productivity in the marine-based sector was higher than the overall regional rate for five of the eight Irish regions.  相似文献   
106.
The Kolar Gold Fields are some of the best known gold deposits in India. An example of ore valuation utilizing 49 ore blocks of the Oriental lode of the West Reefs, explored and developed in the Nundydroog mines, is given. In this reef system, there are large ore reserves of sulfidebearing quartz reefs, and the gold distribution is erratic both along strike and downdip. Ore valuation at present is based on the arithmetic mean of samples taken at peripheral positions of the blocks. Samples taken from internal portions of the blocks give a totally different picture of the value. To correct this discrepancy, normal regression and lognormal regression of internal block and total block values, over peripheral block values have been used to evaluate the deposits. The valuation efficiency criterion shows the logarithmic variance for distribution of ratios of unregressed and regressed block values with the corresponding arithmetic mean of internal stope values as observed inside the blocks. The studies have shown that the logarithmic variance is minimum if the logarithmic regression is used, thereby indicating maximum efficiency. Further, the undervaluation and overvaluation of low- and high-grade blocks is less for the logarithmic example. With help of the logarithmic regression equation an effective pay limit of 177.8 in.-dwt has been found for selective mining, for peripheral block values corresponding to the official pay limit of 240 in.-dwt.NGRI contribution number 71-281.  相似文献   
107.
人居环境评价在城市规划政策研究中的工具性作用   总被引:1,自引:0,他引:1  
从认识论的视角出发,提出人居环境评价作为一种工具,在城市规划与城市发展政策中具有三个层面的作用,一是表达,二是交流与合意,三是分析和决策。结合上述观点,对国内外相关研究的进展进行了评述。结果表明,目前,我国人居环境评价的研究成果大部分定位于空间表述,以交流与合意,分析和决策为目标的研究很少,因此限制了研究成果在政策中的深层次应用。为了改变这一现状,急需加强人居环境的价值化评价和政策效果的分析,使人居环境评价上升为更高级的研究工具,以便在政策实践中发挥更大作用。  相似文献   
108.
不动产估价模式研究综述   总被引:1,自引:0,他引:1  
回顾了传统估价理论与方法及其存在的不足,评述了基于多元回归技术、神经网络技术、空间统计学等方法的自动估价模式,探讨了地理信息技术对不动产估价的重要作用。  相似文献   
109.
以山东华能德州发电厂现役储灰库"灰水"对潜水位的影响和水量均衡原理,确定其对库区潜水位影响范围;对拟建储灰库区根据水文地质条件,采用非稳定流基本方程对库区潜水水位进行预测,得出平原储灰库区地下潜水位最大影响范围为750m.  相似文献   
110.
基于土地利用数据集的三江源地区生态系统服务价值变化   总被引:1,自引:0,他引:1  
本文采用千年生态系统评估(Millennium Ecosystem Assessment, MA)的理论框架, 结合市场价值法、影子工程法、机会成本法等方法, 以土地利用变化数据、社会经济调查资料为数据源, 对三江源地区1985、1996、2000、2008 年生态系统服务价值进行了评估, 评估的生态系统服务类型包括食物生产、调节气候、净化空气、水源涵养、控制侵蚀、废弃物降解、营养物质循环7 项。结果表明:三江源地区1985、1996、2000、2008 年生态系统服务总价值分别达到602.94 亿元、601.58 亿元、603.60 亿元、669.90 亿元, 整体呈现先降低后增加的趋势。其中, 调节气候、涵养水源的价值占据较大比例。三江源地区的生态系统服务所蕴含的巨大经济价值将对维持该地区生态平衡、保障区域可持续发展发挥重要作用。  相似文献   
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