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811.
吕占林  张国富  王莉 《山东国土资源》2007,23(6):2007/3/19-2007/6/16
烟台三菱水泥有限公司燕地石灰石矿,位于山东省栖霞市臧家庄镇燕地村东。矿山南北长约1000m,东西宽300~500m,属水泥厂石灰石原料专用矿山,矿山固定资产1.32亿元,各类机械设备以进口为主,功能齐全,性能优良。矿山总体为凹陷露天开采,公路运输开拓,开采工艺为:钻孔→爆破→采装→运输→破碎→均化堆积。采用垂直走向拉开段沟,水平分层,由上而下的开采方法,台段高度10m,同时生产的平台2~3个。  相似文献   
812.
Based on research on information organization and visualization mechanism of multimedia electronic map, this paper proposes an organization method about spatial information and multimedia information of multimedia electronic map: seamless spatial data were organized and managed by stratified expansion R-tree and Quad-tree hierarchy; and multimedia information data were organized and managed by hypermedia model based on an electronic map. Considering electronic map features, the paper also proposes a method for spatial date organization, which integrates Digital Landscape Model and Digital Cartographic Model, and a hybrid model between vector and raster spatial data. Then, the paper studies information visualization mechanism of multimedia electronic map. Finally, the paper certifies the results via a case of multimedia electronic map authoring tools software-Atlas2005.  相似文献   
813.
Miao  Zhi-yong  Lv  Yun-long  Xu  Ding-jie  Shen  Feng  Pang  Shun-wan 《GPS Solutions》2017,21(1):111-122
GPS Solutions - Under high dynamic conditions, a robust tracking loop is essential for accuracy positioning with the global position system. In previous studies, the extended Kalman filter...  相似文献   
814.
通过中国极地考察"十五"能力南极两站卫星通信网络系统项目的建设,我国南极考察站的广域网通信能力和站区网络通信能力已经有了很大提高。系统阐述南极两站的广域网通信现状,内容包括南极两站卫星通信链路的建设情况、考察站计算机网络系统建设情况以及该系统所提供的服务情况,涉及卫星通信、局域网以及VOIP等技术;对未来几年极地考察通信中可能会采用的通信技术建设提出建议。  相似文献   
815.
结合国内征地拆迁的现状和特点,构建失地民众征地拆迁满意度模型,利用湖北省嘉通高速公路沿线村落的调查数据,采用基于PLS法的结构方程模型对征地拆迁民众满意度进行了实证分析。研究表明:失地民众对征地拆迁满意度不高,主要与民众对补偿款的满意程度、就业扶持力度以及信息是否公开透明等影响因素有关,此外,民众除了重视物质方面的补偿,还同等看重信息透明度、政策公平度等“无形”补偿。根据研究结果,建议政府与开发商合作提高就业扶持力度,利用新媒体平台拓展信息覆盖程度,完善纠纷解决机制。  相似文献   
816.
Glacier variations in the Tibetan Plateau and surrounding mountain ranges in China affect the livelihood of over one billion people who depend on water from the Yellow, Yangtze, Brahmaputra, Ganges and Indus rivers originating in these areas. Based on the results of the present study and published literature, we found that the glaciers shrank 15.7% in area from 1963 to 2010 with an annual area change of -0.33%. The shrinkage generally decreased from peripheral mountain ranges to the interior of Tibet.The linear trends of annual air temperature and precipitation at 147 stations were 0.36°C(10a)~(-1) and 8.96 mm(10a)~(-1) respectively from 1961 to 2010. The shrinkage of glaciers was well correlated with the rising temperature and the spatial patterns of the shrinkage were influenced by other factors superimposed on the rising temperature such as glacier size, type, elevation, debris cover and precipitation.  相似文献   
817.
818.
The Kuluketage block, located in the northeast Tarim craton, is one of the largest Precambrian blocks in the Xinjiang province. Recently, many banded iron formation (BIF)‐type (Superior‐type) deposits have been discovered in the western part of the Kuluketage block. These deposits occurred in the Paleoproterozoic Shayiti Formation, Xingditage Group, which has a nearly E–W distribution in the southern Xinger and Xingdi faults. Tremolite biotite schist and quartzite are the main wall rocks. The geochemical characteristics of schist indicate that the BIFs occurred in a passive continental margin environment. The LA–ICP–MS zircon 206Pb/238U ages of BIF and late syenite are 1945 ± 10 Ma(MSWD = 0.77) (weighted average age) and 1974 ± 27 Ma(MSWD = 1.05) (upper intercept age), respectively, indicating that the BIFs occurred in the Paleoproterozoic. In addition, the approximately 1.9 Ga magmatic and metamorphic events are consistent with the global‐scale 2.1–1.8 Ga collisional orogen events which are associated with the assembly of the Columbia supercontinent. The geochemical characteristics show that magnetite and quartz are dominant components (total content, 91.65–98.22 wt.%), and the Zr(Nb) and TiO2, Zr(Nb) and Al2O3 and Zr and Y/Ho display strongly positive correlations, illustrating the addition of crustal materials into the chemical precipitate of the original BIFs. The higher Zr, Nb and Al2O3 contents and a lower Y/Ho ratio of the Kuluketage BIFs indicate a higher terrigenous detrital component contaminant compared to BIFs of North China Craton (NCC). The rare earth and yttrium (REY) distribution patterns show a slight LREE enrichment and weak Eu positive anomaly features, indicating that the source of Fe and Si of the Kuluketage BIFs is mainly from the contribution of low‐temperature hydrothermal alteration of the oceanic crust. In addition, along with the decreasing BIF depositional age, the declining of Eu anomaly values reflects the increasing importance of low‐temperature hydrothermal solutions relative to high‐temperature hydrothermal solutions. Moreover, no Ce anomalies in studied BIFs, NCC and Xinyu BIFs are attributed to relative reducing environmental condition when the original BIFs precipitated.  相似文献   
819.
820.
Lv  Mingzhu  Song  Yan  Li  Xijia  Wang  Mengsi  Qu  Ying 《Theoretical and Applied Climatology》2022,147(1-2):737-752
Theoretical and Applied Climatology - As an important parameter of the Earth’s energy budget, the planetary albedo of Earth varies with the dynamics of atmospheric and surface variables. In...  相似文献   
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