Who governs here? Informal resource extraction,state enforcement,and conflict in Ghana     

《Global Environmental Change》2019

Over the past two decades, “illegal” natural resource extraction has become a significant driver of environmental change and social conflict across the Global South. In response, numerous Sub-Saharan African states have engaged in governance reforms that heed calls to securitize – or, establish and consolidate state control over – natural resources. In Ghana, securitization has served to entrench the informal economy as domestic producers, marginalized in the process of reform, continue to utilize non-state institutions to maintain access. While the Ghanaian state has branded “illegal” resource extraction a major environmental, social, and national security concern, it has responded to this threat unevenly; it has violently enforced its authority in some contexts but remained relatively indifferent in others. This article explores the phenomenon of selective enforcement to explain patterns of violence that have emerged between state and society in response to both securitization and informality. Drawing on a multimethod approach, I find that natural resource governance authority remains fragmented across resource contexts, and that the configuration of authority and interests on the ground shapes the extent of state intervention. I propose a natural resource typology that identifies when the state is most likely to enforce its authority, and the degree of violent conflict likely to result. Ultimately, I contend that domestic patterns of enforcement are shaped primarily by: 1) competition with local power holders over resource entitlements and 2) global conservation and extraction priorities. While specific to Ghana, this argument can provide important insights into the relationship between informal extraction, state enforcement, and social conflict in other Global South contexts.  相似文献   

面向带电作业的手臂末端输出力评估方法     

林子  熊鹏文  何孔飞  张发辉 《南京气象学院学报》2019,11(2):186-191

为了解决带电作业时手臂末端输出力的准确控制,提出一种基于表面肌电信号（sEMG信号）和支持向量机回归（SVR）实现对手臂末端施力的评估方法.通过手握机械手臂末端的手柄,做往复推拉运动,记录此时手柄处的力传感器的数据F,同时利用3组肌电信号传感器同步采集手臂的肌电信号.将肌电信号提取特征后,与力F组合成样本集合S,在样本集合中随机抽取50%的样本数据作为训练集,分别训练BP神经网络、GRNN神经网络以及SVR神经网络.最后用训练好的神经网络对整个样本集中的力F进行预测,并用均方根误差和相关系数评估模型的预测效果.结果显示,SVR神经网络的预测效果较好,其均方根误差为3.074 0,相关系数为0.951 7.  相似文献   

A GIS-based approach for detecting pollution sources and bioavailability of metals in coastal and marine sediments of Chabahar Bay,SE Iran     

《Chemie der Erde / Geochemistry》2015,75(2):185-195

Chabahar Bay in SE of Iran is a shallow semi-enclosed environment affected by anthropogenic activities. In this paper, 19 sediment samples were collected and concentration of selected metals (Cu, Pb, Zn, Cd, Ni, Cr, Co, V and Fe) was determined using ICP-MS analytical method. Sediment samples from five stations were also selected for sequential extraction analysis and concentration of metals in each fraction was determined using ICP-OES. In order to investigate the environmental quality of Chabahar Bay, geographic information system (GIS) along with geochemical data, environmental indices and statistical analyses were used. Calculated contamination degree (C_d) revealed that most contaminated stations (Ch3, S1 and S3) are located SE of Chabahar Bay and contamination decreases in a NW direction. The S9 station, west of the bay, is also contaminated. High organic matter (OM) content in the sediments is most likely the result of fuel and sewage discharge from fishing vessels along with discharge of fishing leftovers. Significant correlation coefficient among OM, Fe, Cu, Pb, Zn and Cd seemingly reflects the importance of the role that OM and Fe oxy-hydroxides play in the metals mobility. The results of hierarchical cluster analysis (HCA), computed correlation coefficient and sequential extraction analysis suggest that Cu, Pb, Zn and Cd probably come from antifouling and sea vessel paints, while Ni, Cr, Co, V and Fe are most likely contributed by ophiolitic formations located north of the bay and/or deep sea sediments. Average individual contamination factors (ICFs) indicated that the highest health hazard from the bay is posed by Cu, Pb and Zn.  相似文献   

戊基磷酸二戊酯萃取色层分离-电感耦合等离子体质谱法测定铀产品中9种杂质元素     

朱留超  王同兴  赵永刚  徐常昆  赵立飞  姜小燕  赵兴红 《岩矿测试》2015,34(4):414-419

铀产品中杂质元素的含量测定在核法证学溯源分析或燃料元件厂质量检验中具有重要应用价值,保证测量的准确度主要在于控制流程空白、提高杂质元素的回收率。本文建立了戊基磷酸二戊酯(UTEVA)树脂快速分离铀与杂质元素、电感耦合等离子体质谱法(ICP-MS)测定杂质元素含量的系统流程。结果表明,UTEVA树脂对铀的吸附能力强,铀样品取样量为16.43 mg时,全流程对铀的去污因子大于3×105,9种杂质元素(锰钼镍铜铬铝钛钒镉)的回收率为95.1%~105.1%,国家标准物质GBW04205中杂质元素的分析结果与参考值在不确定度(k=2)范围内一致。本工作建立的分离流程对铀的去污效果好,特别适用于样品量少的情况下铀中杂质元素的分析,为核法证分析最终的归因溯源或燃料质量检验提供了技术支持。  相似文献   

基于FastICA算法和MODIS数据的水稻面积提取   总被引：1，自引：0，他引：1       下载免费PDF全文

耿利宁  景元书  杨沈斌  浩宇 《大气科学学报》2015,38(6):819-826

以苏、皖、赣三省为研究区域,采用FastICA算法从MODIS数据中提取2010年水稻种植面积,并验证该算法在混合像元分解中的有效性。在对2010年46景8 d合成地表反射率产品数据进行预处理的基础上,结合MODIS土地利用产品和平滑滤波算法,构建耕地类型像元的I_LSW和I_NDV时相变化曲线。依据I_LSW和I_NDV曲线在水稻移栽期前后的变化规律,并根据由各地区水稻I_NDV时相曲线计算得到水稻相似性指数,从MODIS影像中提取水稻像元。采用FastICA算法对潜在水稻像元水稻生长期内的I_NDV时相曲线进行分解,计算每个像元的水稻丰度,绘制水稻丰度图,获取研究区各省水稻分布和种植面积。利用统计年鉴数据和样方资料对FastICA算法提取的水稻面积进行了验证。结果显示:采用水稻相似性曲线有利于提高稻田识别效率,所获取的水稻分布与实际情况吻合;FastICA算法能够分解不同地区水稻I_NDV时相曲线;与统计资料比较,江苏、安徽、江西三省水稻面积的提取精度分别为86.4%、87.9%、51.5%。江西水稻面积提取误差主要出现在地形起伏较大的山区。  相似文献   

激光雷达点云电力线自动提取算法     

李德友  李彩林  李祥珅  王柏涛 《测绘通报》2021,(6):33-38

针对当前电力线提取方法自动化程度和精度不高的问题,本文从点云数据的空间分布特征出发,提出了一种高效的电力线自动提取方法。首先基于自然裂点法,将点云数据按高程分类后去除地面点;然后对数据进行空间划分,基于子空间的点密度及空间结构特征的差异化,利用地物分割算法去除电塔点和残留的植被点;最后利用基于欧氏距离分割的电力线自动检测算法,实现单根电力线的快速、高精度提取。提取结果和拟合试验表明,该方法能在复杂地形下实现电力线的自动提取,极大提高了电力线的提取效率和精度。  相似文献   

室内楼层平面导航路网模型的自动生成     

李华蓉  彭映雪  李海明 《测绘通报》2021,(4):79-84,104

室内路网模型作为室内导航研究的基础,如何自动生成室内路网模型成为近年的研究热点。对于目前自动路网模型研究中出现的复杂环境适应度不够的问题,本文提出了一种室内楼层平面路网模型的自动提取方法。它将室内空间分为公共空间和专属空间两类,从而形成公共空间路径和专属空间路径,并用转换点将两类路径进行衔接;最终利用提取的公共空间路径、专属空间路径和连接路径构成楼层平面导航路网模型。基于此方法,将某学校教学楼一层建筑平面图生成平面自动路网模型,并从路径完整度、准确度及寻路情况3个方面与手动路网模型进行了对比分析,其表现良好。  相似文献   

面向野外地质调查工作的道路提取方法研究     

高婷  黄颖  郭明强 《测绘工程》2021,30(2):13-16

为弥补传统的依靠管理组织、法律、经济、教育等进行对野外地质工作安全管理工作的不足,通过百度SDK采集GPS步行轨迹数据,基于单向GPS轨迹数据的特点,进行轨迹的分割分段处理。最后利用BP神经网络算法拟合道路,通过反复实验确定BP网络的参数配置信息。并以中国地质大学西区为研究区域,提取路网信息,验证算法的有效性和实用性。为野外地质调查工作的信息化建设和救援指挥调度系统建设提供重要的技术支撑。  相似文献   

一种基于室内点云数据的建筑墙线提取     

孙宪龙  韩李涛  周丽娟  郭佳 《测绘工程》2021,30(2):65-71

针对室内点云数据无结构化属性、数据间无连接、不承载语义信息且数据点密度高的特点,结合建筑物点云几何特征和室内导航需求,通过数据降维简化建筑几何特征提取的复杂性,提出一种基于室内点云数据提取建筑物墙线的方法。该方法首先通过向特定方向投影,利用点云密度直方图完成天花板面、地板面和房间墙面的初步分割;然后将房间墙面点云数据向地面投影,生成点云分布矩阵并将其转化为二值图,利用Hough变换算法提取直线,并利用直线方程求取交点得到备选墙线;最后将备选墙线和墙线点云二值图进行叠加从而获取最终建筑墙线。  相似文献   

车载LiDAR点云中的建筑物特征提取     

王婷婷 《北京测绘》2021,35(1):41-45

针对车载LiDAR点云数据处理复杂、时间长的问题,本文以地物不同特征值作为建筑物自动提取算法的依据,通过点云数据预处理、聚类分析等一系列流程最终实现一般建筑物点云的自动提取。通过两个实验区点云数据的提取与相应的实际地物进行精度分析对比,结果表明本文算法对实例测区环境下的不同建筑物点云提取具有较好的有效性,满足数字城市三维建模的精度要求。  相似文献