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排序方式: 共有383条查询结果,搜索用时 15 毫秒
81.
目的 分析了四维地籍的概念与需求,提出了时空宗地的概念,探讨了时空宗地的演化过程,给出了土地的恒等、类型、收缩与扩展4种权益变换和产生、消亡、边界调整、划入、划出与复合分并6种空间演化。基于4种空间拓扑关系与13种时间拓扑关系,建立了时空宗地的时空拓扑关系。在此基础上,结合地籍相关理论与技术发展,构建了四维地籍概念模型,并依据实现策略不同,提出了标签式、混合式与完全式3种解决方案。 相似文献
82.
基于详细的统计数据,从时间、空间、结构等多个纬度,对中国探矿权及地质勘查投资情况进行了时间序列、因素相关性等对比分析和综合研究,为政府管理部门制定政策和规划提供参考依据。通过研究,揭示了影响探矿权及地质勘查投资的主要因素、底层逻辑和发展规律,并认为受国内外宏观经济增速放缓、地缘政治等因素影响,特别是国内相关产业政策、生态和环境保护压力,“十三五”期间中国探矿权数、地质勘查投入和新发现矿产地持续大幅度减少。“十三五”期间,新立探矿权同比减少52.1%,注销探矿权数是“十二五”期间的3.7倍多。油气矿产的探矿权登记面积和地质勘查投资分别占全国的96%和77.6%;非油气矿产探矿权数占全国的90%以上,有近60%的非油气探矿权在西部地区;非油气地质勘查投资中,水工环及科技等投资额占居半壁江山。预计中国在能源矿产、战略性矿产等勘查领域将增加勘查投入,地质勘查投资将于2024年后逐渐走出低谷。 相似文献
83.
Usage of an early warning and information system Web-site for real-time seismicity in Iceland 总被引:1,自引:1,他引:0
Iceland has been subjected to destructive earthquakes and volcanic eruptions throughout history. Such events are often preceded
by changes in earthquake activity over varying timescales. Although most seismicity is confined to micro-earthquakes, large
earthquakes have occurred within populated regions. Following the most recent hazardous earthquakes in 2000, the Icelandic
Meteorological Office (IMO) developed an early warning and information system (EWIS) Web-site for viewing near-real-time seismicity
in Iceland. Here we assess Web-site usage data in relation to earthquake activity, as recorded by the South Iceland Lowland
(SIL) seismic network. Between March 2005 and May 2006 the SIL seismic network recorded 12,583 earthquakes. During this period,
the EWIS Web-site logged a daily median of 91 visits. The largest onshore event (M
L 4.2) struck 20 km from Reykjavík on 06 March 2006 and was followed by an immediate, upsurge in usage resulting in a total
of 1,173 unique visits to the Web-site. The greatest cluster of large (≥M
L 3) events occurred 300 km offshore from Reykjavík in May 2005. Within this swarm, 9 earthquakes ≥M
L 3 were detected on 11 May 2005, resulting in the release of a media bulletin by IMO. During the swarm, and following the
media bulletin, the EWIS Web-site logged 1,234 unique visits gradually throughout the day. In summary, the data reveal a spatial
and temporal relationship between Web-site usage and earthquake activity. The EWIS Web-site is accessed immediately after
the occurrence of a local earthquake, whereas distant, unfelt earthquakes generate gradual interest prompted by media bulletins
and, possibly, other contributing factors. We conclude that the Internet is a useful tool for displaying seismic information
in near-real-time, which has the capacity to help increase public awareness of natural hazards. 相似文献
84.
This paper outlines mining aspect of view to reclamation studies based on rather simpler but more practical analyses in terms
of legislations and regulations in Turkey. This paper also presents the results of various multi-disciplinary experimental
studies aimed at the development of a reclamation proposal for an open pit mine located in the Istanbul Agacli region. Within
the scope of this study, the current conditions and environmental features of the working area and its surrounding were evaluated.
Various experimental studies were carried out on the representative samples taken from the overburden material and water sources
in order to detect the existence of any contamination and also to determine the properties of samples subjected to the reclamation.
Then, both environmental features and the results of experimental studies of the working area were evaluated. At the end of
the evaluation, a simple and practicable reclamation proposal was developed. 相似文献
85.
Hao Jiang Qian Li Xian Zhou Yanqiu Chen Shuwen Yi Hai Wang 《International journal of geographical information science》2017,31(12):2359-2381
Human mobility patterns have been widely investigated due to their application in a wide variety of fields, for example urban planning and epidemiology. Many studies have introduced spatial networks into human mobility analyses at the collective level. However, these studies merely analyzed spatial network structure, and the underlying collective mobility patterns were not further discussed. In this paper, we propose a collective mobility discovery method based on community differences (CMDCD). We constructed spatial networks where nodes represent geographical entities and edge weights denote collective mobility intensity between geographical entities. The differences between communities detected from the networks constructed in different periods were then identified. Since collective spatial movement has a large influence on network structure, we can discover groups with different mobility patterns based on community differences. By applying the method to data usage detail records collected from the cellular networks in a city of China, we analyzed different collective mobility patterns between the Spring Festival vacation and workdays. The experimental results show that our method can solve these two problems of identifying community differences and discovering users with different mobility patterns simultaneously. Moreover, the CMDCD method is an integrated approach to discover groups whose mobility patterns have changed in different periods at the large spatial scale and the small spatial scale. The discovered collective mobility patterns can be used to guide urban planning, traffic forecasting, urban resource allocation, providing new insights into human mobility patterns and spatial interaction analyses. 相似文献
86.
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88.
基于倾斜摄影技术在农村房屋权籍调查测量中的应用 总被引:2,自引:0,他引:2
李颀 《测绘与空间地理信息》2016,(6)
介绍了基于无人机倾斜摄影系统,快速实现真实三维自动建模并利用三维模型进行立体量测的技术流程和作业方法。利用上述技术在农村房屋权籍调查测量中进行了应用探索,为突破以往只能依靠野外实地测量提供了另外一种高效的解决方案。 相似文献
89.
We used a mixed-methods approach to assess the impact of a ‘forest-friendly’ titling program on previously untitled lands surrounding the Cuyabeno Reserve in Ecuador. Such programs are part of an increasing trend in tenure formalization intended to simultaneously strengthen tenure security, reduce deforestation, and open the door for more incentive-based conservation programs. We use quasi-experimental methods to estimate and compare the impact of titling on forest outcomes for lands that are titled with certain limitations on the ownership bundle of rights, alongside lands titled but without these restrictions. This quantitative analysis is paired with results from a series of focus group interviews with landowners to understand their experiences with the titling effort, particularly tied to the restrictions. Our results point to a statistically significant impact of titling with restrictions on reducing deforestation by 34%, whereas titling without such restrictions resulted in no significant effect. When we explore impacts according to annual deforestation rates, the results suggest that titled lands are buffered from the surges in deforestation that otherwise occurred on untitled lands and more broadly across the region. While ‘forest-friendly’ restrictions had more of an effect on forest outcomes than titled lands without, the insights shared by landowners suggest important concerns about equity and unjust burdens on current households that could risk livelihood options for future generations. 相似文献
90.
哈萨克斯坦地处中亚核心位置,是丝绸之路经济带的重要节点和战略枢纽,具有丰富的矿产资源,地缘政治经济意义重大,是中国企业开展国际矿业投资合作的重要目标国之一。本文在系统梳理哈萨克斯坦基本国情、主要矿产资源特征及开发现状、地质工作程度和地矿管理体系等基础上,对哈萨克斯坦的矿业投资环境进行了评价,分析了矿业投资的有利和不利条件。研究认为哈萨克斯坦矿产资源禀赋优势突出,油气、铀、铬、金、钨、铅、锌及铜等矿种的资源储量居世界前列;全国仅有10%~15%的已探明矿产资源处于开发阶段,采矿业发展潜力巨大;哈萨克斯坦的总体投资环境优越,吸引外资力度逐渐加大,矿产勘探开发水平不断提升。但中国企业开展矿业投资也存在竞争力不足,以及面临政策法规不稳定、地质技术资料不可靠及运营等方面的风险。为此,建议中国投资者一方面要加强对哈萨克斯坦优势矿产的投资力度,积极拓展合作方式及合作领域;另一方面要注重与哈萨克斯坦各利益集团建立良好关系,结合企业优势,综合评价矿业项目,做好风险预警防范;同时,在投资过程中要尊重地方文化习俗,积极履行社会责任。 相似文献