Dizhen xuebao, 2022 地震动合成方法的应用前景与其所能表达的有效频带范围紧密相关。本文研究基于频率波数域格林函数的地震动合成方法（FK法），分析频带范围的关键影响要素及处理措施。在介绍计算原理的基础上，概括FK法合成地震动的主要影响要素，分析地壳速度模型对子源地震矩、破裂时间和传播时间的影响。随后，分析格林函数传播宽频带地震波的能力，提出格林函数计算中的频带影响参数的建议值。为分析FK法的震源模型辐射宽频带地震波的能力，重点考察控制子源错动过程的震源时间函数和上升时间。研究认为，FK法具有合成宽频带地震动的能力 ...
Zelin Cao +3 more
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Multi frequency hopping network station sorting based on joint feature clustering in complex environment [PDF]
, 2023 In order to remove interference from hybrid signals and sort each frequency hopping station signal, a multi frequency hopping network station sorting algorithm based on joint feature clustering was proposed.Firstly, short-time Fourier transform was ...
Jiazheng WANG +4 more
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Fast blind detection of short-wave frequency hopping signal based on MeanShift [PDF]
, 2022 In the complex short-wave channel environment, combined with time-frequency analysis technology, a fast blind detection algorithm of the connected domain labeled frequency hopping signals based on MeanShift algorithm was proposed to reduce the influence ...
Jing LIANG +6 more
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Short wave protocol signals recognition based on Swin-Transformer [PDF]
, 2022 Aiming at the problem that it is difficult to identify the protocol to which the signal belongs in the complex SW channel environment, a SW protocol signal recognition algorithm based on Swin-Transformer neural network model was proposed.Firstly, the ...
Di WU +5 more
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Time-frequency analysis of freqency-hopping signals based on sparse recovery [PDF]
, 2013 To overcome the common shortcomings shared by the existing methods: weak suppression noise interference and feeble performance of time-frequency concentration,a novel time-frequency analysis method based on sparse repre-sentation was developed,which ...
Jun-hua WANG +3 more
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基于小波变换的2013年芦山MS7.0地震前姑咱台钻孔应变异常时频分析
Dizhen xuebao, 2019 2013年4月20日芦山MS7.0地震前，四川省姑咱台四分量YRY-4型钻孔应变仪记录到显著的高频应变畸变信号。为了避免该畸变信号的高频部分在时频演化过程中发生频率混叠现象，同时便于讨论同一研究频段内震前更早记录到的弱应变异常时段与显著应变异常时段的相关性，本文对2012年1月1日至2013年4月20日期间姑咱台的钻孔应变数据进行了时频分析，并使用时域分段的小波变换方法，在局部时频谱中提取了应变异常，分析了各应变异常的频率相关性。结果表明，研究频段内存在两个峰值频率 ...
Weichen Zhang +4 more
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Application of invariant moment method for HAPS ISAR imaging with micro parts [PDF]
, 2013 To resolve the micromotion in the HAPS(high altitude platform station) ISAR system,the invariant moment method for ISAR imaging with micro parts was proposed.Firstly,invariant moment tool was applied to classify the echoes of different sub-aperture,and ...
Hai-bin SUN +3 more
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Application of iterative generalized short-time Fourier transform to fault diagnosis of planetary gearboxes [PDF]
, 2017 Due to the effect of the modulation part, the energy diffuses around the surrounding area of dominating frequencies and diminishes the readability of the time-frequency representation when short-time Fourier transform (STFT) is used to process ...
FENG Zhi-peng, ZHANG Dong
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Non-stationary signal combined analysis based fault diagnosis method [PDF]
, 2020 Considering the complementarity between the deep learning,spectrum and time frequency analysis methods,a multi-stream framework was designed by combining the convolutional network,Fourier transform and wavelet package decomposition methods,with the aim ...
Huimin LU +4 more
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Exploration for effects of acoustic stimulus on movement behavior and HSP70 expression of two kinds of marine crustaceans [PDF]
, 2016 水下噪声会潜在的引起海洋生物紧张，分散和掩蔽这些海洋生物重要的声信号，进而对海洋生物的行为和生存造成影响。近几十年来，随着人类社会的不断发展，人们将发展目光投向了占有全球71%面积的海洋。伴随海洋事业的快速发展，海洋工程噪声对海洋生物的影响引起了人们的极大关注。虽然目前已有不少研究成果评估了水下工程噪声对海洋生物的影响，这些噪声包括轮船、打桩、地震勘探以及风电场等水下噪声，表明海洋工程等人为噪声对鱼类以及海洋哺乳动物都将造成了不同程度的影响和伤害。但是 ...
周韦峥嵘
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