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排序方式: 共有260条查询结果,搜索用时 31 毫秒
181.
图斑合并(聚合和融合)是专题地图综合中一个很重要的任务。将小于面积阈值的图斑群的空间视觉冲突分为四类,针对不同的类型采取不同的策略,重点讨论了邻接小图斑群的渐进式合并方法。该方法有效地简化了整个计算过程,提高了计算效率,并使得合并前后的变化值达到最小。 相似文献
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规则格网DEM是DEM的主要表示方式,应用最为广泛,影响DEM质量的关键因素便是内插过程,包括内插精度和效率两个方面。现有的诸多规则格网DEM内插方法基本都不能兼顾内插精度和效率,很大程度上制约了DEM的生产。本文在分析已有方法的基础上,提出了基于Delaunay冲突区域搜索策略的TIN内插规则格网DEM方法,并以实验对该方法进行验证和分析。实验结果表明文中所提方法对规则格网DEM内插精度与效率行之有效。 相似文献
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地图数据库图形输出中要素关系处理 总被引:3,自引:2,他引:3
本文提出了利用地图数据库的检索功能,建立要素图形输出的定量优先级、地理要素图形大小,及基于地图数据库的图形冲突位置的探测方法,并将要素图形输出中的关系划分为五种进行分别处理。 相似文献
187.
Jacob van Etten Joost Jongerden Hugo J. de Vos Annemarie Klaasse Esther C.E. van Hoeve 《Geoforum》2008,39(5):1786-1797
We examine environmental aspects of the conflict between the Turkish state and the insurgent Kurdistan Workers Party (Partiya Karkerên Kurdistan or PKK). Since the early 1990s, several civil society groups have claimed that the Turkish army burned forests and destroyed other livelihood resources in the Kurdistan region of Turkey as it evacuated settlements. We report the results of a case study of destruction in Tunceli, eastern Turkey, undertaken in order to evaluate support for such claims. We demonstrate the use of geospatial techniques in case-specific approaches to the study of armed conflict. Through the analysis of satellite images, we verified eyewitness reports and confirmed that substantial burnings did indeed take place in the study area between 1991 and 1994. We argue that this destruction was not irrational or wanton, but that it was part of a strategy used by the Turkish army in the early 1990s that aimed at actively transforming the war environment. 相似文献
188.
Human–wildlife conflict (HWC) is a growing problem for communities located at the borders of protected areas. Such conflicts commonly take place as crop-raiding events and as attack by wild animals, among other forms. This paper uses a feminist political ecology approach to examine these two problems in an agricultural village located at the border of Rajaji National Park in Uttarakhand (formerly Uttaranchal), India. Specifically, it investigates the following three questions: What are the “visible” and “hidden” costs of such conflict with wildlife? To what extent are these costs differentially borne by men and women? How do villagers perceive any such differences? Survey and interview data were collected from over 100 individuals in the study site over a period of 9 months in 2003–2004. It was found that for participants in this study, costs of HWC included decreased food security, changes to workload, decreased physical and psychological wellbeing, economic hardship, and at times an increase in illegal or dangerous activities. The research also showed that although women in the study area bore a disproportionate burden of these effects, roughly half of survey respondents perceived that men and women were equally affected. A possible explanation for this gap considers the relationships between gendered uses of space, work, status, and identity. The findings illustrate the importance of addressing both visible and hidden costs of HWC for members of park communities and support a call for increased gender-sensitivity in HWC research. 相似文献
189.
对动态多目标TSP的动态程度和目标冲突程度的度量问题进行了研究,首次给出了问题的动态程度和目标冲突程度的度量方法.根据这些方法,可计算出动态多目标TSP问题状态的变化程度和目标之间的冲突程度.它们对动态多目标TSP的算法设计具有重要的指导意义. 相似文献
190.
National parks are an important manifestation of the United States’ democratic ideal and attract more than 300 million visits annually. However, racial/ethnic minorities are substantially underrepresented among visitors, and this has led to three hypotheses—marginality, subculture, and discrimination—designed to help explain this pattern of visitation. Moreover, research suggests that the awareness of and visitation to national parks may relate to several variables, including race/ethnicity, socio-economic characteristics, and childhood visitation history. To investigate these issues, an online general population survey of New York City residents was conducted. Study findings suggest that (1) racial/ethnic minorities are underrepresented at some types of parks but not others, (2) Hispanics and Blacks generally have lower rates of awareness about national parks than Whites, and (3) awareness and childhood visitation history significantly affect visitation to national parks. These findings suggest potential approaches to enable and encourage diverse racial/ethnic groups to engage with national parks. 相似文献