农村集体土地确权测量中的塔尖交会技术研究     

张太鹏 《测绘与空间地理信息》2016,(9):192-194

简要介绍了农村集体土地确权测量中的塔尖交会技术,生成平差文件的方法,以及平差计算的理论模型,最后给出了平差实例,极大地提高了作业效率,达到了满意的效果。  相似文献   

GPS精密卫星钟差估计研究     

孟范伟 《测绘与空间地理信息》2016,(9):77-79

随着精密单点定位技术的发展,对于精确的卫星坐标以及卫星钟差改正精度的要求越来越高,精密卫星星历以及精密卫星钟差的求解成为制约精密单点定位技术发展的瓶颈。本文基于修复周跳的载波相位观测值与相位平滑伪距观测值,采用无电离层延迟星间单差精密卫星钟差估计模型,在先估计出整周模糊度后,进行了精密卫星钟差的估计,并采用与IGS事后精密钟差作二次差的方法进行精度分析,这对于提高精密单点定位精度具有一定的意义。  相似文献   

高分二号卫星影像融合方法探析   总被引：2，自引：0，他引：2  

熊德峰 《测绘与空间地理信息》2016,(9)

图像融合技术是卫星影像处理过程中的一个重要步骤,它可以将全色影像的高空间分辨率特点与多光谱影像的高光谱分辨率特点有机地结合起来,使得融合后的影像更利于后续解译。由于融合处理方法的原理以及获取影像的传感器特性不同,不同的卫星影像适合于不同的融合方法。针对高分二号卫星影像的特点,本文采用Gram-Schmidt融合法、FIHS变换方法、HPF方法、Pansharp方法进行试验。实验结果表明:HPF方法所得融合结果在光谱特性保持方法性能最优,而Pansharp方法融合结果在信息量的保持以及清晰度方面效果更优,因此,在实际应用中,应根据具体需求进行方法选择。  相似文献   

基于线要素动态化简的匹配算法比较与评价     

陈竞男  钱海忠  王骁  何海威  胡慧明 《测绘科学技术学报》2016,(1)

矢量线要素数据来源多样,细节层次不一,限制了已有匹配算法正确率的提高,同时也给算法评价带来困难。化简可以减少线要素细节层次,提取其主要形态,据此提出一种基于线要素动态化简的匹配算法评价新方法。对不同匹配算法采用相同数据,在相同化简算法支撑下进行匹配,从而实现对不同匹配算法的评价。首先,阐述动态化简方法提取线要素主要形态的过程;其次,利用动态化简分别辅助4种已有匹配算法,获取每个匹配算法的最优匹配正确率;最后,将4种匹配算法的原始匹配结果与加入动态化简后的匹配结果进行对比,分析化简对匹配结果的影响,并把该影响运用到匹配算法的比较和评价中来。其中,1通过匹配正确率变化、误匹配等分析了匹配算法的数据适用性;2通过化简比例系数K变化时新增匹配数量的统计,评价了匹配算法对线要素局部细节的敏感程度并提出该指标的量化方法;3结合匹配算法采用的匹配相似度指标对其作出评价。  相似文献   

Rights in places: An analytical extension of the right to the city     

《Geoforum》2016

Following recent scholarship on place and place-making, we identify key challenges for contemporary empirical research using the “Right to the City” as an analytic. We seek to distinguish between the aspirational “right” articulated as a political and conceptual call to arms on one hand, and the “actually existing rights” that are carved out through both formal and informal mechanisms (including political protest) in the everyday city on the other. Actually existing rights are defined not through fiat or via momentary revolutionary acts, but through the durability of relationships between multiple actors, including residents, citizens, states, and corporate agents. We re-articulate urban rights as actually contingent and agonistic properties of the relationships that citizens have with places. This paper uses the historic conflict over community gardens in New York as an illustration of how thinking of rights regimes as multiple, overlapping, and placed helps better illuminate potential political interventions. Thinking of rights and places as plural, overlapping, and contingent is analytically productive because it highlights (rather than overwriting) conflicts between competing articulations of rights and privileges in cities.  相似文献   

Fairtrade bananas in the Caribbean: Towards a moral economy of recognition     

《Geoforum》2016

Working through a Caribbean case study, this paper examines the networks and associations of Fair Trade bananas as they move both materially and morally from farms in St Vincent and the Grenadines to supermarkets and households in the United Kingdom. In doing so, the paper provides grounded empirical evidence of Fair Trade’s moral economy as experienced by banana producers in the Caribbean. The paper follows Nancy Fraser’s distinction between ways of framing justice to argue that, in order to transcend its complex postcolonial positionalities, the Fair Trade Foundation needs to include recognition in its moral economy as well as representation and redistribution. The paper compares the moral framework of Fair Trade as an ideology and social movement with the lived experience of certified Fairtrade banana farmers in the Windward Islands who work mostly for, rather than within, an idealized moral economy. The paper also contributes to several recent debates in the agri-food literature exploring the interconnections between production and consumption, the role of materiality in contemporary food networks, the historical and (post)colonial nature of food moralities, and links between political and moral economies of food. Following an outline of recent debates about the moral economies of food and its relation to Fair Trade as a movement, the paper dissects the moral economy of the Fairtrade Foundation, highlighting the historical and geographical, material and symbolic, gendered and generational ways that food producers in the Global South (in this case, banana farmers in St Vincent and the Grenadines) may be counterposed to ‘responsible’ consumers in the Global North. Despite the good intentions of those who promote the Fair Trade movement through the Fairtrade Foundation and the Fairtrade Labelling Organisation (FLO), our case study reveals a moral economy of non- (or partial) recognition, which has a range of unintended consequences and paradoxical effects.  相似文献   

Flow processes and sedimentation in unidirectionally migrating deep‐water channels: From a three‐dimensional seismic perspective          下载免费PDF全文

Chenglin Gong  Yingmin Wang  Ronald J. Steel  Jeff Peakall  Xiaoming Zhao  Qiliang Sun 《Sedimentology》2016,63(3):645-661

Three‐dimensional seismic data were used to infer how bottom currents control unidirectional channel migration. Bottom currents flowing towards the steep bank would deflect the upper part of sediment gravity flows at an orientation of 1° to 11° to the steep bank, yielding a helical flow circulation consisting of a faster near‐surface flow towards the steep bank and a slower basal return flow towards the gentle bank. This helical flow model is evidenced by the occurrence of bigger, muddier (suggested by low‐amplitude seismic reflections) lateral accretion deposits and gentle channel wall with downlap terminations on the gentle bank and by smaller, sandier (indicated by high‐amplitude seismic reflectors) channel fills and steep channel walls with truncation terminations on the steep bank. This helical flow circulation promotes asymmetrical depositional patterns with dipping accretion sets restricted to the gentle bank, which restricts the development of sinuosity and yields unidirectional channel migration. These results aid in obtaining a complete picture of flow processes and sedimentation in submarine channels.  相似文献   

塔里木盆地西部阿克莫木气藏地层压力特征          下载免费PDF全文

刘强  徐怀民  江同文 《地质科学》2016,(1):149-156

阿克莫木气田目前已有多口井完钻,各井在钻揭白垩系砂岩储层前,对地层压力纵向上的变化规律认识不清,在什么层位及深度下7″套管意见仍不统一。本文根据目前研究现状和生产面临问题,对白垩系各组地层分布规律、压力特征进行了详细研究,认为白垩系克孜勒苏群、库克拜组分布稳定,压力窗口相近,白垩系东巴组与上覆古近系阿尔塔什组压力窗口相近。建议今后该区钻探7″套管应下至库克拜组顶部-东巴组底部,减少地层漏失和油气勘探风险。  相似文献   

新疆三塘湖盆地牛圈湖区块异常低压成因及压力演化定量分析     

康媛  孙卫  盛军  时建超  刘艳妮  赵婷 《地质论评》2016,62(1):103-110

三塘湖盆地牛圈湖区块中生界侏罗系西山窑组储层具有典型的异常低压油藏特征,晚白垩末期储层达到最大埋深,此时下部芦草沟组烃源岩演化程度达到最大,随着油气持续向储层充注,此时地层压力达到最大,可达30.33~50.74MPa。本文从引起油藏异常低压的主要因素入手,定量分析了构造抬升与地层剥蚀、地层温度降低、成岩作用中的"耗水作用"以及矿物蚀变引起的自生体积缩小等因素对地层压力的影响。这些因素共同作用导致了地层压力降低,其中溶蚀作用中矿物蚀变所形成的"耗水作用",使地层压力下降24.4%~37.1%,是造成储层异常低压的首要因素,同时矿物蚀变导致自身体积缩小并导致储层压力下降16.5%~24.8%,地层温度降低和构造运动对储层压力降低影响相对较弱,降低幅度分别为7.9%~8.6%和4.8%~8.1%。以上种种因素的共同作用,使得地层压力下降17.45~37.85MPa,最终形成现今异常低压的分布格局。  相似文献   

丝绸之路经济带甘肃黄金段找矿勘查新进展     

刘建宏  黄万堂  贾志磊 《地质论评》2016,62(S1):169-170

丝绸之路经济带已成为国家战略,赋于了上合组织新的内涵,也给地质工作者提出了新的要求。甘肃是古丝绸之路的锁匙之地,是丝绸之路经济带上的“黄金路段”。2014年甘肃省提出利用拥有古丝绸之路贯穿境内1600 km的战略通道优势,打造丝绸之路经济带的黄金段,使其成为向西开放的战略平台、经贸物流的区域中心、产业合作的示范基地、人才交流的桥梁纽带。本文就甘肃省矿产资源优势、找矿勘查新进展及向西走出去提出建议。  相似文献