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401.
利用SPOT-5卫星遥感影像更新1:10000地形图初探   总被引:2,自引:0,他引:2  
通过利用SPOT-5(2.5m)卫星遥感影像更新山地1:10000地形图试验研究,总结了利用SPOT-5(2.5m)卫星影像更新1:10000地形图的工艺方法。成功地用于重庆市部分无航片山区的1:10000地形图更新。  相似文献   
402.
The Makhonjwa Mountains, traditionally referred to as the Barberton Greenstone Belt, retain an iconic Paleoarchean archive against which numerical models of early earth geodynamics can be tested. We present new geologic and structural maps, geochemical plots, geo- and thermo-chronology, and geophysical data from seven silicic, mafic to ultramafic complexes separated by major shear systems across the southern Makhonjwa Mountains. All reveal signs of modern oceanic back-arc crust and subductionrelated processes. We compare the rates of processes determined from this data and balance these against plate tectonic and plume related models. Robust rates of both horizontal and vertical tectonic processes derived from the Makhonjwa Mountain complexes are similar, well within an order of magnitude, to those encountered across modern oceanic and orogenic terrains flanking Western Pacific-like subduction zones. We conclude that plate tectonics and linked plate-boundary processes were well established by 3.2-3.6 Ga. Our work provides new constraints for modellers with rates of a 'basket' of processes against which to test Paleoarchean geodynamic models over a time period close to the length of the Phanerozoic.  相似文献   
403.
专题地图是富有空间表现力的专题信息地图可视化工具,随着网络技术的发展,促进了网络与专题地图的结合,使得基于网络的专题信息的共享与交互操作变得日趋重要。本文简单介绍了Carto Vista软件的结构体系以及在网络专题制图过程中的优越性,并以安徽省专题数据库系统B/S平台为例,对利用Carto Vista软件进行网络专题地图制作方法、流程、特色等问题进行探讨与研究。经过实验与系统配置,取得了良好的效果,验证了Carto Vista在在线动态专题地图构筑中的可行性。  相似文献   
404.
Although climate change is highly prevalent in the media, people in Europe and the United States are often unsure about climate change terms, processes, and its personal consequences. In other words, climate change communication seems to be largely failing so far. Among other communication tools, maps are widely used for explanatory purposes by scientists and the media. Here two questions arise: first, whether high map complexity may be too intricate to be understood and discourage people from deciphering the map; and second, whether personal interest in climate change can be influenced by the phenomenon depicted or the map’s scale. In a survey conducted among 109 students in the USA, 63% of respondents preferred a simple map, but a substantial subset, 37%, asked for complexity to receive more information. Regional phenomena evoked more concern than far-off phenomena (concern level index difference of 0.93 on a 5-ranked Likert scale). The advantage of maps showing local areas could not be statistically confirmed.  相似文献   
405.
While academics increasingly recognize the complexity of phenomena that do not easily conform to our reductive understandings, it sometimes remains difficult to reconcile this with a need for clear and conclusive arguments. In this article I share the contradictory forces and unresolved discrepancies in my own work as a means to better understanding the process of coming to terms with empirical and theoretical messiness. In particular, I draw on the Theory of Cognitive Dissonance to better understand the psychological influence this concept has in pushing us to make sense of the world in a way that downplays contradictions, counter-trends, complexity, gaps and unresolved loose ends. Having identified this largely subconscious dynamic, the pursuit for an agentic suspension of the need for cognitive harmony can be a productive means for thinking through the results of our research. Using my own work understanding the impact of the U.S.–Mexico border on the Tohono O’odham, an indigenous group based in Arizona and Sonora, I share how the perspectives of the groups with which I work has helped me think through contradiction in writing up the results of my research. For a more complete understanding I must embrace the counter-currents at play and alternative understandings of these events and places-even if I cannot fully explain away such incongruent forces.  相似文献   
406.
朱园媛  朱庆  张叶廷  彭明军  高山 《测绘学报》2015,44(9):1036-1041
针对城市侧视地图上建筑物轮廓线主要依靠人工交互提取,成本高昂、效率低下且精细度和准确度有限的问题,提出了一种任意视角侧视地图中建筑物轮廓线的自动提取方法。采用深度缓冲区分割算法获取单个建筑物对象的颜色缓冲区,顾及了存在建筑群的情况和建筑物密集区域的遮挡问题,再基于颜色缓冲区追踪建筑物轮廓线。为了保持遮挡一致性且便于匹配提取出的矢量轮廓线与栅格侧视地图,本文还提出了基于投影空间分块加载三维城市模型的方法。最后,以武汉市典型三维城市模型数据为例,证明了该方法的有效性和可靠性。  相似文献   
407.
探讨移动影像与规划专题信息终端平台的设计与部分功能实现。分析平台建设的背景和实现的技术路线;论述平台总体构架及功能设计。用实例阐述历史影像对比、专题加载和查询统计3个功能模块的实现,介绍ArcGIS Runtime SDK for Android、JSON和SQLite技术在本项目中的应用。  相似文献   
408.
Highly technological in vitro fertilization (IVF) treatment is available at relatively few medical centers in rural United States. This research derives a spatial accessibility surface for IVF centers in a rural Midwestern state through the application of computational methods that consider spatial and non-spatial parameters to discover potentially underserved areas in the state. These methods include a modified gravity model and techniques from spatial interaction modeling. The approach develops an enhanced accessibility index that incorporates three key sociodemographic variables describing patients seeking infertility healthcare in Iowa that have been identified based on a survey of IVF care practitioners in the state. Self-organizing map techniques are used to reveal cluster locations based on the degree of match between census sociodemographic data and the expert-identified variables. The spatial accessibility surface is combined with the sociodemographic clusters to define an enhanced measure of spatial accessibility. The results suggest that while the state's IVF centers are located in tracts characterized by high spatial accessibility, at least 19% of patients travel from census tracts classed as moderate to low accessibility. This result reveals some opportunities for service improvements for these locations. Interestingly, for tracts that are characterized as having a lower patient sociodemographic match, high spatial accessibility does not appear to be a factor that improves the likelihood of patient care, at least for the variables investigated as part of this research.  相似文献   
409.
分析中国科学院(CAS)、法国国家空间研究中心(CNES)、加拿大自然资源部大地测量局(NRCan)和加泰罗尼亚理工大学(UPC)2021-01~08的全球实时电离层格网(RT-GIM)产品的精度。结果表明:1)以IGS事后全球电离层格网(GIM)为参考,CAS、CNES、NRCan和UPC产品的RMS分别为3.93 TECu、4.01 TECu、4.50 TECu和3.86 TECu;2)以基准站dSTEC为参考,CAS、CNES、NRCan和UPC产品的STD分别为4.42 TECu、4.40 TECu、4.96 TECu和4.42 TECu。在全球范围内选取21个测站进行连续7 d的定位测试,以高程方向残差95%分位数统计不同实时电离层产品的定位增益。相比于广播电离层模型的定位结果,CAS、CNES、NRCan和UPC产品在北半球高程方向的定位精度分别提升11.9%、18.3%、3.4%和15.5%。  相似文献   
410.
一种基于平面地质图的复杂断层三维构建方法   总被引:1,自引:0,他引:1  
在分析平面地质图数据特点的基础上,为准确表达复杂断层的空间几何形态和相互之间的关系,引入了由地质形体的轮廓线构建而成的线框架模型概念;修正了边界表示法模型有效构建的基本条件;从地层与断层之间的关系角度详细阐述了有效构建线框架模型的方法;提出了以线框架模型为基础的断层面整体构建技术思路,解决了复杂断层面三维构建问题。  相似文献   
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