内蒙古浩尧尔忽洞金矿三维建模与深部成矿预测     

李楠  曹瑞  叶会寿  李强  王义天  吕喜平  郭娜  苏元祥  郝建瑞  肖扬  张帅  楚文楷 《地学前缘》2021,28(3):170-189

内蒙古浩尧尔忽洞金矿位于华北克拉通北缘,是我国黑色岩系金矿的典型代表,其赋存于白云鄂博群比鲁特组的碳质板岩中,品位低而可采储量大.针对金矿增储保障问题,本文以矿床模型和"三位一体"找矿预测方法为指导,采用三维建模可视化技术,首先,构建了浩尧尔忽洞金矿三维找矿模型,实现了矿区的透明化、立体化;其次,开展了地球物理电磁联合...  相似文献   

基于不同GNSS增强系统的激光巡线数据分析          下载免费PDF全文

吴涛  张星炜  王红星  黄郑  宋煜  梁森 《全球定位系统》2021,46(1):77-82

无人直升机搭载激光雷达(LiDAR)进行输电线路巡检具有高精度、低成本的优点,为了获取高精度输电线路三维点云高精度地理空间坐标,采用基于基站差分动态后处理(PPK)、江苏省连续运行参考站(JS-CORS)、千寻位置(QX-CORS)等三种不同定位服务方式进行输电线路巡检,分析了三种定位下获取的点位定位精度以及点云质量....  相似文献   

面向卫星遥感影像检索定位的深度学习全局表征模型评估与分析     

施群山  蓝朝桢  徐青  周杨  胡校飞 《地球信息科学学报》2022,24(11):2245-2263

如何快速获取无辅助参数卫星遥感影像地理位置是非合作方式获取的遥感影像信息充分利用的一个关键,利用影像特征的相似性对卫星遥感影像检索来实现定位,是获取无辅助参数卫星遥感影像地理位置的有效手段。为了探寻影像深度学习全局特征用于无辅助参数卫星遥感影像检索定位的可行性,建立了包括Precision@K、平均排序、特征提取时间、特征相似性计算时间、硬件消耗等,涵盖有效性、效率2个方面共计5类指标的评估体系。采用谷歌地球提供的影像数据作为基准影像,在资源三号夏季及冬季数据集上,分别利用AlexNet、VggNet、ResNet、DenseNet、EfficientNet等几种代表性的卷积神经网络预训练模型提取基准影像及查询影像的全局特征,依据评估体系中的指标,对这些网络模型的影像表征效果进行全面的量化评估与分析。试验分析结果表明,DenseNet、ResNet-18、VggNet这3个深度学习神经网络预训练模型提取的全局特征,综合表征效果较好,可有效用于卫星遥感影像检索定位;当K值取200时,DenseNet网络模型的Precision@K值可以达到59.5%,ResNet-18和VggNet网络...  相似文献   

基于等角边界距离相似性的遥感影像面状图斑匹配研究     

陈军  马世岩  陈玲  江明桦 《地球信息科学学报》2022,24(11):2234-2244

基于形态特征的目标匹配是地图空间认知、地表位置自动感知等领域的重要方法。然而,由于不同数据源的遥感影像提取的同一个空间目标在空间尺度和局部形态上存在一定的差异,现有形态匹配算法难以获得较高的匹配精度。本文以等角边界距离编码及相似性算法为核心,提出了面向遥感影像的面状图斑匹配方法。(1)从面目标的质心以10°为间隔,顺时针方向从质心向外引36条射线,获取面目标的边缘点,形成等角边界距离编码;(2)提出了与该编码相适应的几个综合形态指标,包括自相似度、圆形度、形态复杂度和质心偏移度,并建立了面状图斑相似度算法;在此基础上,结合近邻目标的形态相似度,构建了遥感影像面状图斑匹配算法;(3)从不同数据源的在线遥感影像上提取中国西部湖泊与全球湖泊,开展面状图斑匹配实验。通过实验,发现本文的面状图斑相似度算法相对于按距离采样的相似度算法,召回率提升了13.8%;在添加近邻目标相似度约束的基础上,面状图斑匹配精度达到90%以上。通过算法适应性分析,发现该算法在一定的投影变形下仍能保持一定的匹配精度;如果空间目标及其邻域目标的总体形态和分布接近,不同空间尺度的匹配精度保持在80%以上。本文的研究为地图空...  相似文献   

GENDER DIFFERENCES IN COMMUTING DISTANCE,RESIDENCE, AND EMPLOYMENT LOCATION: METROPOLITAN HAIFA 1972 AND 1983*     

Orna Blumen  Aharon Kellerman 《The Professional geographer》1990,42(1):54-71

This paper highlights three major aspects of gender differences in employment in Haifa, Israel (1972 and 1983): commuting distance, place of residence, and employment location. In 1972 working womenaposs residences were more central-city-oriented, whereas in 1983 they were more suburbanized. Commuting distances increased between 1972 and 1983 for both sexes, but more for men than for women. This shorter “female'’distance is related to the location of employment and its occupational segregation. The lower commuting values in Haifa compared to other places relate to the size, housing patterns, and structure of the study area, and to its levels of suburbanization and automobile ownership.  相似文献   

A study on regional difference of China’s paid urban landuse system and grading     

Liming Dong  Xiangming Li  Changchun Feng 《中国地理科学(英文版)》1994,4(3):193-203

At present, paid urban landuse system is one of the most important economic reform in China. In the other words, landuse right can be transferred and land users must pay the rent to the state according to the quality of land. It is necessary to apply the theory of rent and location to the economic approaisal of urban land. China is vast in territory. Is’s geographical condition and economic development vary from place to place, so does the urban land value. In order to reveal the difference of land value between different cities, the following method is used. (1) Analysing the factors and elements that affect the quality of urban land. Six factors including 17 elements were selected in this paper: macrolocation of a city, benefit of urban aggregation, infrastructure investment, output value of urban land, potential of urban land, and investment intensity. (2) Deciding the weight andvalue of each factor. (3) Appraising each element separately. (4) Accounting the value of all factors and getting the total appraisal score of each city. (5) Grouping the 430 Chinese cities into sevencategories according to the appraisal values. The result shows that all the cities in the category with the highest land output values are in the coast belt, whereas most cities in the inland and outlying areas are belong to the category with low rank. For example, 87% of the cities in the outlying regions are belong to the lowest rank. Although there are some relationship between the size of cities and urban land rank, generally speaking, the larger the city, the higher the urban land rank. In fact, the locational condition is the most important factor which influences the rank of urban land.  相似文献   

A STUDY ON RATIONAL LOCATION OF THE COTTON PRODUCTION IN CHINA     

祝卓 《中国地理科学(英文版)》1991,1(2):129-140

Cotton is the leading cash crop in China. The cotton sown area accounts for about 30per cent of the total sown area of all the various cash crops. It is the main material used in the textile industry in China. More than 95per cent of textile materials were cotton during the 1950s; and it still occupies 80per cent at present. There are some problems concerning rational location of cotton production in China. In order to solve the problems existing in civil cotton production and supply, in view of strategy, a number of cotton production bases must be selected and built step by step in a planned way. The location of cotton production should be adjusted progressively in accordance with the existing problems. The existing cotton production regions should be consolidated and improved. The cotton production region of the middle and lower reaches of the Huanghe River should be renewed quichly to make it become the largest stable and high-yield cotton preduction region. In the regions with suitable natural condi  相似文献   

PRINCIPLES FOR THE LOCATION OF SYNAGOGUES: SYMBOLISM AND FUNCTIONALISM IN A SPATIAL CONTEXT     

Yosseph Shilhav 《The Professional geographer》1983,35(3):324-329

Two traditional Jewish approaches to the location of synagogues can be found, one symbolic and one functional. The locational requirements are not identical; the symbolic approach deals with idealistic spatial status while the functional approach poses realistic locational demands. This spatio-locational conflict reflects a problematic situation on both theoretical and practical levels.  相似文献   

Seismic regime of the west Bohemian earthquake swarm region: Preliminary results     

J. Horálek  F. Hampl  A. Boušková  T. Fischer 《Studia Geophysica et Geodaetica》1996,40(4):398-412

Summary The western part of the Bohemian Massif located between two tectonic units, the Moldanubian and the Saxo-Thuringian, is characterized by the re-occurrence of earthquake swarms. The focal region for these swarms includes the territory of West Bohemia and the adjacent territory of SE Saxony and NE Bavaria. During the most recent swarm in December 1985 – January 1986, more than 8000 small earthquakes were recorded; the two largest earthquakes with local magnitudes (M_L) of 4·6 and 4·1. This paper presents a summary of the seismic energy release in space and time for the western part of the Bohemian Massif, based on seismic observations of permanent seismic stations established in West Bohemia since 1986. It was found out that microearthquake activity, mostly of a swarm-like character, persisted between two macroseismically observed swarms. The foci of the microearthquakes predominantly cluster in six main epicentral zones, four of which are located in West Bohemia or in its immediate vicinity in Saxony. The remaining two are in Saxony and in Bavaria. The four epicentral zones in West Bohemia were studied in detail. It was found that the individual zones differ in size, in depth of hypocentres, in geometry, as well as in temporal activity. Moreover, it was found that the seismicity in the most active epicentral zone is closely related to the system of principal tectonic faults referred to as the Kruné Hory fault and the Mariánské Lázn fault.  相似文献   

渭河断陷及邻近地区震源空间分布规律探讨   总被引：1，自引：0，他引：1       下载免费PDF全文

袁志祥  狄秀玲  丁韫玉 《地震工程学报》1998,20(3):73-78

选取１０３°～１１３°Ｅ,３１°～３９°Ｎ范围内陕西、山西、河南、湖北、甘肃、宁夏等省（区）共７９个地震观测台站１９８４—１９９３年的观测资料,对于被４个以上台站所记录到的地震,根据其直达横波与纵波的到时差,采用鲍威尔（Ｐｏｗｅｌ）搜索法重新进行了定位,测定了震源深度,共得到２０５１个可定震中的地震的震源深度数据．作出了渭河断陷及邻近地区现代地震的震中分布图、震源空间分布图、震源深度的平均等值线分布图、震源深度的经向剖面图和纬向剖面图．根据这些资料对震源空间分布规律进行了初步探讨．结果表明,渭河断陷及邻近地区震源的空间分布是不均匀的,与该地区大地构造的差异性及地壳速度结构的非均匀性密切相关．  相似文献