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雅安地区监测井水位预测效能对比研究
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作者 鲁明贵 谷洪彪 +5 位作者 杨耀 芮雪莲 许多湛 马艺宁 张文旭 迟宝明 《地震》 CSCD 北大核心 2024年第3期215-231,共17页
为提高监测井水位映震效果的判别准确度并提升预测效能,本文运用不同方法对雅安地区两条断裂附近的6口监测井水位的映震效果开展了对比判别研究。首先,使用差分法对监测井水位数据进行处理和分析。然后,将水位数据与区域地震活动性的两... 为提高监测井水位映震效果的判别准确度并提升预测效能,本文运用不同方法对雅安地区两条断裂附近的6口监测井水位的映震效果开展了对比判别研究。首先,使用差分法对监测井水位数据进行处理和分析。然后,将水位数据与区域地震活动性的两种参数(能级和最大震级)相结合,分析区域地震活动性与水位波动的关系。接着,在时域和频域两个层面对该组合序列进行分析处理。最后,采用Molchan图表法检验5种方法的预测效能,并选出最佳处理方法及断裂附近预测效能最优的监测井。结果表明:水位与地震活动性参数结合处理相比单独使用水位差分法具有优势,前者能够准确排除地震活动性对水位异常的干扰。6口监测井的最优预测方法各不相同,最优预测天数均在60 d内。通过比较监测井水位对地震的预测效能检验结果,确定了两条断裂区域预测效能最优的监测井。虽然水位与地震活动性两种参数结合处理并不适用于所有监测井,但该方法能够体现水位受地震活动性影响的程度。 展开更多
关键词 井水位前兆 地震活动性 水位数据处理 Molchan图表法 预测效能
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承压含水层中孔压变化规律的振动台实验研究 被引量:1
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作者 张耀文 谷洪彪 +2 位作者 那金 宋洋 张艳 《科学技术与工程》 北大核心 2019年第17期18-24,共7页
为研究不同地震动作用下承压含水层中孔压变化规律及其主要影响因素,开展了基于地震模拟振动台的承压含水层孔隙水压力变化实验研究。结果表明:①地震动作用下孔压变化形态可分为振荡、振荡上升以及阶升三种类型,孔压变化形态及幅度均... 为研究不同地震动作用下承压含水层中孔压变化规律及其主要影响因素,开展了基于地震模拟振动台的承压含水层孔隙水压力变化实验研究。结果表明:①地震动作用下孔压变化形态可分为振荡、振荡上升以及阶升三种类型,孔压变化形态及幅度均与加速度峰值密切相关,而与频率相关度较低;②孔压增量随加速度峰值增大而增大,其增长规律可表示为以加速度峰值为自变量的二次函数;③孔压消散过程基本呈线性规律,且消散速率与加速度峰值大小有关,加速度峰值越大,振后孔压消散速率越快。实验可为后续探究地震动作用下孔压变化信息在含水层中的传递机理提供一定参考。 展开更多
关键词 孔压 加速度峰值 频率 振动台实验
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Effects of tallowtree seed coat on seed germination 被引量:7
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作者 LI Shu-xian gu hong-biao +2 位作者 MAO Yan Yin Tong-ming GAO Han-dong 《Journal of Forestry Research》 CAS CSCD 2012年第2期229-233,共5页
We measured physiological parameters including water uptake in-vitro embryo germination ratio, and seed coat structure observed by scanning electron microscopy (SEM) to explore the influence of seed coat on the germ... We measured physiological parameters including water uptake in-vitro embryo germination ratio, and seed coat structure observed by scanning electron microscopy (SEM) to explore the influence of seed coat on the germination of seeds of tallow tree (Sapium sebiferum (Linn) Roxb.). Tallow tree seeds had good water permeability. We found that germination of cabbage seeds was inhibited when cabbage seeds were soaked in extracted solutions from tallow tree seed coat. Seed coat structure at the side of the radicle appeared to be a barrier to seed germination. We tested methods to break tallow tree seed dormancy. Dormancy of tallow tree seeds was overcome by soaking the seeds in 500 mg·L^-1 or 1000 mg·L^-1 GA3, followed by 100 days of cold stratification. 展开更多
关键词 Sapium sebiferum seed dormancy cold stratification in- hibitory substances gibberellic acid
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Thirty years(1984–2014) of groundwater science teaching and research in China: A dissertation-based bibliometric survey
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作者 ZHAI Yuan-zheng JIANG Shi-jie +4 位作者 TENG Yan-guo WANG Jin-sheng gu hong-biao XIE Liang YIN Zhi-hua 《Journal of Groundwater Science and Engineering》 2015年第3期222-237,共16页
In order to track the footprint of groundwater science teaching and research in China during the past years, a bibliometric analysis was conducted based on the database of China National Knowledge Infrastructure(CNKI)... In order to track the footprint of groundwater science teaching and research in China during the past years, a bibliometric analysis was conducted based on the database of China National Knowledge Infrastructure(CNKI), which covered the time span from 1984 to present and included more than 2.6 million master and doctoral dissertations from hundreds of institutions of China's Mainland. The bibliometric analysis summarized output, geographical, and institutional patterns, as well as research directions and hotspots in groundwater studies in China in the period of 1984-2014. A total of 1 396 groundwater-related dissertations including 1 161 master dissertations and 235 doctoral dissertations, contributed by 128 institutions distributed in 53 cities nationwide, were searched out in the database. It can be seen obviously that, the groundwater science teaching and research in China has experienced a notable growth in the past three decades especially during 2000-2014. Groundwater modeling, resource, and exploitation were the top three major subject categories; China University of Geosciences(Beijing), Jilin University and Chang’an University were the top three productive institutions together accounting for more than one third of the total dissertations and 50% of the doctoral dissertations, which further prompted the cities(Beijing, Changchun, and Xi’an) to become the top three productive cities. The dissertations generally covered all the international research topics, which indicated that hydrogeologists in China have tracked the international frontier closely during the past decades. The keywords analysis revealed that,(1) numerical modeling was still the hottest topic and PHREEQC, MODFLOW, GMS, and FEFLOW were the four most used softwares;(2) the topics related with groundwater pollution and quality developed steadily and rapidly;(3) environmental isotopes and GIS were frequently used tools for hydrogeological condition analysis, and spatial data processing respectively; and(4) the unsaturated zone as an integral part of aquifers attracted more and more attentions from hydrogeologists focus on saturated zone. 展开更多
关键词 GROUNDWATER HYDROGEOLOGY Research hotspot SCIENTOMETRICS Bibliometrics analysis China National Knowledge Infrastructure(CNKI)
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基于核Fisher判别分析方法对北京温榆河及部分支流水质综合评价 被引量:1
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作者 于健 谷洪彪 +3 位作者 王贺 迟宝明 谭立云 刘玉丽 《数学的实践与认识》 北大核心 2020年第22期103-110,共8页
以北京温榆河及其部分支流的8组水样数据作为研究对象,选取F-,Se,As,Cd,Pb,Cr+6,DO,TP,NH3^+-H作为评价指标,将核Fisher判别分析方法引入水质综合评价,以《地表水环境质量标准》(GB3838-2002)Ⅰ~V类水质标准生成核Fisher判别分析法的训... 以北京温榆河及其部分支流的8组水样数据作为研究对象,选取F-,Se,As,Cd,Pb,Cr+6,DO,TP,NH3^+-H作为评价指标,将核Fisher判别分析方法引入水质综合评价,以《地表水环境质量标准》(GB3838-2002)Ⅰ~V类水质标准生成核Fisher判别分析法的训练数据与测试数据,选用高斯核函数,核参数的选取是以测试集分类准确度为衡量标准,建立核Fisher判别分析评价模型,核Fisher模型综合评价果显示南沙河中段水质为Ⅰ类水,南沙河下段,温榆河上段,温榆河中上段,清河,温榆河中段,坝河,温榆河下段水质均为V类水将模型评价结果与内梅罗指数法,Fisher线性判别模型,粒子群支持向量机等模型评价结果作对比,核Fisher判别分析方法能合理反映水质变化,给出符合实际问题的评价结果. 展开更多
关键词 机器学习 FISHER线性判别分析 核FISHER判别分析
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