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我国矿产资源紧缺 能保证2020年需求的只有6种
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《探矿工程(岩土钻掘工程)》 2004年第7期24-24,共1页
关键词 矿产资源 市场需求 地质勘探 地质大调
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Establishment of Geomagnetic Observatories in Pakistan and Repeat Station Results from Northern Part of Pakistan
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作者 Madeeha Ashfaque Ghulam Murtaza +1 位作者 Jean Rasson Chris Turbitt 《Journal of Earth Science and Engineering》 2013年第1期42-49,共8页
A geomagnetic observatory was established at Karachi (geog coord: 24.95°N, 167.14° E), Pakistan in 1983 which comprised of AMOS-Ⅲ (Automatic Magnetic Observatory System). In 2006 SUPARCO (Space and Up... A geomagnetic observatory was established at Karachi (geog coord: 24.95°N, 167.14° E), Pakistan in 1983 which comprised of AMOS-Ⅲ (Automatic Magnetic Observatory System). In 2006 SUPARCO (Space and Upper Atmosphere Research Commission) planned to upgrade the old observatory of Karachi in order to qualify it as an IMO (Intermagnet Magnetic Observatory). Dr. Jean Rasson agreed to give support and assist us in the upgradation. BGS (British Geological Survey) provided a complete observatory instrument setup. Due to perturbations traceable to the increased urbanization, the observatory has been shifted to a site "Sonmiani", 80 km north-west of Karachi, where long term protection from cultural noise is offered. This site in a sparsely built research complex was selected after a magnetic survey. A new observatory has also been established at Islamabad (geog cord: 33.75° N, 72.87° E) which is mountainous region. SUPARCO purchased new equipment for the establishment of new observatories. Plan of upgradation of observatory at Quetta is also under consideration in order to improve the monitoring of geomagnetic field on the western part of Pakistan. Repeat station work has been done for the northern part of Pakistan with the collaboration of IRM, Belgium. The obtained results also compared with the global geomagnetic model (IGRF). 展开更多
关键词 Pakistan geomagnetic observatory KARACHI repeat station survey.
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基于小波消噪的EMD模型在GPS振动信号处理中的应用 被引量:4
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作者 李旋 孙磊 +2 位作者 骆辉 戴吾蛟 何伟 《工程勘察》 CSCD 北大核心 2011年第3期72-76,共5页
经验模式分解和小波分解是当前有效处理非平稳信号的两种时频分析方法,它们各具有其优缺点,适用于不同的应用。从对GPS振动信号的预处理、时域和频域处理入手,结果分析表明,对GPS振动信号先进行小波滤波消除随机噪声的干扰,再应用经验... 经验模式分解和小波分解是当前有效处理非平稳信号的两种时频分析方法,它们各具有其优缺点,适用于不同的应用。从对GPS振动信号的预处理、时域和频域处理入手,结果分析表明,对GPS振动信号先进行小波滤波消除随机噪声的干扰,再应用经验模式分解更有利于变形特征信息的分离和提取,提取的信号与振动平台记录数据更加吻合。 展开更多
关键词 经验模式分解(EMD) 小波分解(WD) 全球定位系统 振动变形
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