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文章以MATLAB技术为平台,以西藏自治区雄村铜矿床为实例,详细讨论了如何开发以克立格理论为基础的固体资源储量估算系统,其中包括模块:数据预处理、变异函数分析、克立格估值、储量估算、地质可靠度评价等.论文使用该系统对西藏自治区雄村铜矿床进行储量预测,得出结果数据表格;并对原生矿体、次生矿体、氧化矿体、总矿体、矿体的自然形态以及在工业品位规范下的矿体形态进行拟合.通过与专业储量估算软件Minesjght的估算结果对比,证明了本系统的可靠性和实用性. 相似文献
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房屋建筑数据是地震重点危险区预评估工作的基础,需基于获取到的房屋建筑信息开展人员伤亡、经济损失、救援物资需求等预评估工作。历年地震重点危险区预评估工作能够通过现场调查得到的房屋建筑信息占比极小,仅能进行抽样调查。因此,为批量完成危险区内全部房屋建筑损失估算,需基于遥感影像获取房屋建筑矢量数据,并建立数据库。为实现全国地震重点危险区预评估工作中大批量建筑物矢量化数据的快速获取,本文采用基于遥感影像的建筑物空间分布数据批量获取方法,得到地震重点危险区内建筑物空间矢量数据,结合现场抽样调查得到的建筑物属性信息,建立地震重点危险区建筑物空间分布数据库,进而为地震重点危险区灾害损失预评估工作提供数据基础。本文采用的方法可广泛应用于地震重点危险区房屋建筑信息获取工作中,可提高工作效率,降低工作成本,提升预评估工作的科学性和准确性。 相似文献
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城乡结合部土地利用变化的信息提取技术与分析--以无锡市为例 总被引:11,自引:0,他引:11
作为两种截然不同的生态系统过渡区,城乡结合部是土地利用/土地覆被变化最激烈地区之一,城乡结合部的土地利用情况日益受到人们重视.本文以无锡市为例,利用3S技术提取城乡结合部的范围和土地利用/土地覆被状况信息,提出了确定无锡市城乡结合部范围边界的半自动提取模型和结合部土地利用类型半自动提取模型,并对无锡市城乡结合部土地利用结构及其变化进行分析,揭示了无锡市城乡结合部土地利用/土地覆被变化特征,据此提出城乡结合部土地合理利用的建议. 相似文献
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Paleoproterozoic volcanic rocks in the southern margin of the North China Craton,central China:Implications for the Columbia supercontinent 总被引:1,自引:0,他引:1
The volcanic rocks of the Xiong'er Group are situated in the southern margin of the North China Craton(NCC).Research on the Xiong er Group is important to understand the tectonic evolution of the NCC and the Columbia supercontinent during the Paleoproterozoic.In this study,to constrain the age of the Xiong'er volcanic rocks and identify its tectonic environment,we report zircon LA-ICP-MS data with Hf isotope,whole-rock major and trace element compositions and Sr-Nd-Pb-Hf isotopes of the volcanic rocks of the Xiong'er Group.The Xiong'er volcanic rocks mainly consist of basaltic andesite,andesite.dacite and rhyolite,with minor basalt.Our new sets of data combined with those from previous studies indicate that Xiong'er volcanism should have lasted from 1827 Ma to 1746 Ma as the major phase of the volcanism.These volcanics have extremely low MgO.Cr and Ni contents,are enriched in LREEs and LILEs but depleted in HFSEs(Nb,Ta,and Ti),similar to arc-related volcanic rocks.They are characterized by negative zircon ε_(Hf)_(t) values of-17.4 to 8.8,whole-rock initial ~(87)Sr/~(86)Sr values of 0.7023 to 0.7177 andε_(Nd)(t) values of-10.9 to 6.4.and Pb isotopes(~(206)Pb/~(204)Pb =14.366-16.431,~(207)Pb/~(204)Pb =15.106-15.371,~(208)Pb/~(204)Pb= 32.455-37.422).The available elemental and Sr-Nd-Pb-Hf isotope data suggest that the Xiong'er volcanic rocks were sourced from a mantle contaminated by continental crust.The volcanic rocks of the Xiong'er Group might have been generated by high-degree partial melting of a lithospheric mantle that was originally modified by oceanic subduction in the Archean.Thus,we suggest that the subduction-modified lithospheric mantle occurred in an extensional setting during the breakup of the Columbia supercontinent in the Late Paleoproterozoic,rather than in an arc setting. 相似文献
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PurposeEvaluate the sensitivity of Gunshot Detection Technology (GDT) relative to Calls for Service. Existing crime data sources have biases that do not present a complete picture of gun-related crime. GDT may offer a new metric for firearm crimes. However, few studies have assessed the accuracy of GDT and its relationship to other measures of violence.MethodsGDT and gun crime-related Calls for Service in Washington, DC during 2010 were studied. Using temporal comparisons for month, day of year, weekday, and hour of the day, spatial comparisons on a quarter-mile square grid, and a Poisson-Lognormal-CAR spatial regression model on a combined grid by time period dataset, we examined the sensitivity of GDT activations relative to gunshot-related calls for service.ResultsThe results showed that relative GDT sensitivity changed by time and by space. In particular, the relative sensitivity of GDT was much stronger in the evening and at nighttime than in the daytime. In terms of spatial variation, we found that GDT sensitivity decreased with distance from the nearest zone centroid. In addition, there were two small geographic areas in the study area in which the relative GDT sensitivity was lower than expected.ConclusionsGDT systems identify the frequency and locational accuracy of gunshot incidents, particularly at nighttime. This technology has the potential to improve data collection on gun use and violence and produce more accurate representations if the temporal and distance limitations of the technology are understood. GDT may improve gun detection and, thereby, improve police operations and public support for police. 相似文献
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中国林业可持续发展及其关键科学问题 总被引:21,自引:0,他引:21
在扼要介绍和分析中国森林资源的状况、演变和存在问题的基础上,着重探讨了中国林业可持续发展的战略和为实现林业可持续发展所必需研究解决的关键科学问题。在林业可持续发展战略部分全面论述了它的前提、目标、方针和六项对策措施。在关键科学问题部分则分别从森林的环境功能、森林的生产功能、林木遗传改良、森林保护和森林资源管理等五个方面列出所需要研究解决的关键科学问题,为制订今后的科学研究规划提供参考。 相似文献
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With the continuous emergence of global development problems, the dynamic conservation and sustainable development of Important Agricultural Heritage Systems (IAHS) have been assigned greater importance. However, due to the complex structure, multi-component, dynamic, and open characteristics of IAHS, there are neglected problems which need to be solved in conservation practice, such as component element ambiguity, obscurity of the conservation redline, etc. This study defined the concept of key elements (KE) of IAHS, put forward a conceptual framework of KE identification, conducted empirical research by taking Honghe County of Honghe Hani Rice Terraces System (HHRTS) as an example and analyzed the level of recognition motivations for different stakeholder groups. The following conclusions were drawn: 1) The KE of HHRTS are grain crops, rice species biodiversity, terrace construction and maintenance technique, Hani traditional festivals, Hani traditional foods, and virgin forest; 2) The reasons behind the KE priorities of farmers, businessmen and tourists were at the micro level, the reasons of officers were at the middle level and the reasons of researchers were at the macro level. The empirical study conducted in HHRTS showed that the proposed conceptual framework could identify KE of IAHS effectively, and provided a theoretical perspective for the structuring of and essential need for IAHS research. Moreover, the KE recognition levels of different stakeholder groups reflected their potential action strategies. We should focus on the coherence of policies and measures in both the microscale and macroscale to balance the diversified demands of stakeholders, and to stimulate their enthusiasm for participation in the conservation in order to improve the management level of IAHS sites. 相似文献