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Comparison of the earthquake detection abilities of PhaseNet and EQTransformer with the Yangbi and Maduo earthquakes

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Earthquake Science 2021年第5期34卷 425-435页

作者： Ce Jiang lihua Fang liping Fan boren li Institute of Geophysics China Earthquake AdministrationBeijing 100081China Guangdong Earthquake Agency Guangzhou 510070China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Institute of Disaster Prevention Sanhe 065201China

PhaseNet and EQTransformer are two state-of-the-art earthquake detection methods that have been increasingly applied *** evaluate the generaliz-ation ability of the two models and provide insights for the development of new models,this study took the sequences of the Yunnan Yangbi M6.4 earthquake and Qinghai Maduo M7.4 earthquake as examples to compare the earthquake detection effects of the two abovementioned models as well as their abilities to process dense seismic *** has been demonstrated from the corresponding research that due to the differences in seismic waveforms found in different geographical regions,the picking performance is reduced when the two models are applied directly to the detection of the Yangbi and Maduo *** has a higher recall than EQTransformer,but the recall of both models is reduced by 13%-56%when compared with the results rep-orted in the original *** analysis results indicate that neural networks with deeper layers and complex structures may not necessarily enhance earthquake detection *** designing earthquake detection models,attention should be paid to not only the balance of depth,width,and architecture but also to the quality and quantity of the training *** addition,noise datasets should be incorporated during *** to the continuous waveforms detected 21 days before the Yangbi and Maduo earthquakes,the Yangbi earthquake exhibited foreshock,while the Maduo earthquake showed no foreshock activity,indicating that the two earthquakes’nucleation processes were different.

关键词： earthquake detection deep learning PhaseNet EQTransformer Yangbi earthquake Maduo earth-quake

Relocation of the Foreshocks and Aftershocks of the 2021 Ms 6.4 Yangbi Earthquake Sequence,Yunnan,China

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Journal of Earth Science 2022年第4期33卷 892-900页

作者： Ting Yang boren li lihua Fang Youjin Su Yusheng Zhong Jingqiong Yang Min Qin Yaji Xu Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Institute of Disaster Prevention Sanhe 065201China Yunnan Earthquake Agency Kunming 650224China

An Ms 6.4 earthquake occurred in Yangbi,Yunnan,China on May 21,2021,which has obvious foreshock activity and abundant *** on the seismic observation data recorded by the Yunnan Seismic Network three days before and seven days after the mainshock,a doubledifference location method was used to relocate 2133 earthquakes of the Yangbi *** are mostly distributed to the southeast of the mainshock in a unilateral rupture *** sequence exhibits a SE-trending linear alignment with a length of about 25 km,and most of the focal depth is above 12 *** with the seismic distribution and focal mechanism results,we infer that the strike of the seismogenic fault is about 140°,and dipping to the *** fault structure revealed by the seismic sequence is complex,with the NW segment exhibiting a steep dip and relatively simple structure of strike-slip rupture and the SE segment consisting of several branching *** Yangbi Earthquake is a typical foreshock-mainshock-aftershock sequence,and the mainshock is likely triggered by the largest *** earthquake occurred in the boundary between high-and lowvelocity anomalous zone,where is susceptible to generate large earthquakes.

关键词： Yangbi Earthquake Weixi-Qiaohou-Weishan fault earthquake sequence double-difference relocation earthquakes

High-precision relocation of the aftershock sequence of the January 8,2022,M_(S)6.9 Menyuan earthquake

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Earthquake Science 2022年第2期35卷 138-145页

作者： liping Fan boren li Shirong liao Ce Jiang lihua Fang Institute of Geophysics China Earthquake AdministrationBeijing 100081China Guangdong Earthquake Agency Guangzhou 510405China Fujian Earthquake Agency Fuzhou 350003China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China

The 2022 Menyuan M_(S)6.9 earthquake,which occurred on January 8,is the most destructive earthquake to occur near the Lenglongling(LLL)fault since the 2016 Menyuan M_(S)6.4 *** relocated the mainshock and aftershocks with phase arrival time observations for three days after the mainshock from the Qinghai Seismic Network using the double-difference *** total length and width of the aftershock sequence are approximately 32 km and 5 km,respectively,and the aftershocks are mainly concentrated at a depth of 7-12 *** relocated sequence can be divided into 18 km west and 13 km east segments with a boundary approximately 5 km east of the mainshock,where aftershocks are *** east and west fault structures revealed by aftershock locations differ *** west fault strikes EW and inclines to the south at a 71°-90°angle,whereas the east fault strikes 133°and has a smaller dip *** strain accumulates at conjunctions of faults with different slip rates where it is prone to large *** on surface traces of faults,the distribution of relocated earthquake sequence and surface ruptures,the mainshock was determined to have occurred at the conjunction of the Tuolaishan(TLS)fault and LLL fault,and the west and east segments of the aftershock sequence were on the TLS fault and LLL fault,*** migrate in the early and late stages of the earthquake *** the first 1.5 h after the mainshock,aftershocks expand westward from the *** the late stage,seismicity on the northeast side of the east fault is higher than that in other *** migration rate of the west segment of the aftershock sequence is approximately 4.5 km/decade and the afterslip may exist in the source region.

关键词： Menyuan earthquake aftershock sequence double-difference relocation Lenglongling fault Tuolaishan fault

Robust stabilization of uncertain stochastic time-varying delay systems with nonlinearity

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Robust stabilization of uncertain stochastic time-varying de...

具有非线性扰动的线性多时变时滞系统的鲁棒镇定

第37届中国控制会议

作者： boren li School of Computer Science and Network Security Dongguan University of Technology

The problem of robust stabilization for uncertain stochastic time-varying delay system with nonlinearity is studied in this ***,by using new method to deal with the integral terms,novel delay-dependent robust stochastic stability criterion is presented for stochastic system without the time-varying parameter *** with previous results,the novel method can sufficiently utilize more negative items ***,based on the criterion obtained,robustly stochastic stability condition is proposed for uncertain stochastic ***,robustly stochastic stabilization result is obtained,and an appropriate memory state feedback controller can be ***,a numerical example is given to show our results are effective and less conservative than other reports in previous literatures.

关键词： Robust stabilization Time-varying delay Nonlinearity Stochastic system

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系统科学与数学 2014年第4期34卷 392-401页

作者：李伯忍东莞理工学院计算机学院东莞523808

研究了一类非线性扰动满足范数有界的线性多时变时滞系统的鲁棒镇定问题,通过引入适当的自由权矩阵,应用线性矩阵不等式技术和构造恰当的Lyapunov泛涵,得到了系统镇定的时滞相关的充分条件,此外,还给出了求解无记忆状态反馈控制器的设... 详细信息

研究了一类非线性扰动满足范数有界的线性多时变时滞系统的鲁棒镇定问题,通过引入适当的自由权矩阵,应用线性矩阵不等式技术和构造恰当的Lyapunov泛涵,得到了系统镇定的时滞相关的充分条件,此外,还给出了求解无记忆状态反馈控制器的设计方法,最后,用数值例子验证了文中所得的结论的正确性及求解方法的有效性.

关键词：自由权矩阵非线性扰动时变时滞鲁棒镇定

具有非线性扰动的线性多时变时滞系统的鲁棒稳定性

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系统科学与数学 2010年第7期30卷 887-894页

作者：李伯忍胥布工华南理工大学自动化科学与工程学院广州510640 东莞理工学院计算机学院东莞523808

采用了一类新型积分等式,研究了具有非线性扰动的线性多时变时滞系统的时滞相关鲁棒稳定性问题,并推广得到一般的时滞相关-时滞变化率无关的鲁棒稳定性条件.数值实例表明,稳定性条件的保守性也有所减少.

关键词：积分等式非线性扰动时变时滞鲁棒稳定性

Stability Criteria for Systems with Interval Time-Varying Delay

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Stability Criteria for Systems with Interval Time-Varying De...

具有非线性扰动的不确定多个变时滞系统的有记忆非脆弱状态反馈控制（英文）

第三十届中国控制会议

作者： li boren College of Computer,Dongguan University of Technology,Dongguan,Guangdong,523808,P.R.China

＜正＞The cross-product terms in the derivative of Lyapunov-Krasovskii functional are disposed by using two integral-inequalities, and the state derivative term is reserved by employing Newton-Leibnitz formula and free-weighting ***, stability criterion for nominal system is obtained,then applying S-procedure,stability criterion for linear fractional norm-bounded uncertainty system *** system matrices and Lyapunov matrices in the stability condition of nominal system are separated, parameter-dependent Lyapunov-Krasovskii functional is used to deal with polytopic-type uncertainty ***, numerical examples are given to demonstrate the effectiveness and are improvement of the proposed criteria.

关键词： Lyapunov-Krasovskii functional Robust Stability Time-varying Delay Integral-equality linear matrix inequality(LMI)

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应用数学 2015年第3期28卷 617-627页

作者：李伯忍曾金平东莞理工学院计算机学院广东东莞523808

本文研究不确定非线性多时滞系统的非脆弱鲁棒镇定问题.状态和输入矩阵中的参数不确定性假设是范数有界.延迟是未知的,但随时间变化范围是已知的.对所有容许的参数不确定性,非脆弱鲁棒镇定问题是设计一个记忆脆弱的状态反馈控制器使得... 详细信息

本文研究不确定非线性多时滞系统的非脆弱鲁棒镇定问题.状态和输入矩阵中的参数不确定性假设是范数有界.延迟是未知的,但随时间变化范围是已知的.对所有容许的参数不确定性,非脆弱鲁棒镇定问题是设计一个记忆脆弱的状态反馈控制器使得闭环系统是鲁棒稳定.利用Lyapunov泛函和自由权矩阵方法,以线性矩阵不等式(LMI)的的形式,得到时滞依赖充分镇定判据.数值例子说明所提出的理论结果的有效性.

关键词：自由权矩阵非线性扰动时变时滞反馈控制

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克拉美丽气田石炭系火山岩复杂岩性岩电特征

岩石学报 2010年第1期26卷 291-301页

作者：寇彧师永民李珀任秦小双王磊李晓敏北京大学地球与空间科学学院石油与天然气研究中心北京100871

准噶尔盆地东部克拉美丽气田石炭系火山岩岩石类型复杂多样,且同一岩性由于结构、构造和成分的差异,电性特征差异亦较大,岩性识别困难。本文通过对该区14口井取心段岩电关系研究,认为自然伽马、电阻率、密度三种曲线岩性特征响应明显;... 详细信息

准噶尔盆地东部克拉美丽气田石炭系火山岩岩石类型复杂多样,且同一岩性由于结构、构造和成分的差异,电性特征差异亦较大,岩性识别困难。本文通过对该区14口井取心段岩电关系研究,认为自然伽马、电阻率、密度三种曲线岩性特征响应明显;电阻率、中子、密度、声波四条曲线对火山岩岩石构造特征响应明显。并编制了岩性和岩石构造测井识别交会图版11张。进而利用电测资料识别出该区11种火山岩岩石类型:正长斑岩、二长斑岩、玄武岩、粗面岩、英安岩、流纹岩、霏细岩、沉凝灰岩、熔结凝灰岩、火山角砾岩和熔结火山角砾岩;识别出5种岩石构造类型:正长斑岩中气孔及块状构造和玄武岩中杏仁、碎裂及块状构造。通过本区12口钻井取心后验,测井识别结果与钻井岩心分析结果吻合良好,可作为地区性火山岩测井岩性、岩石构造识别模式。

关键词：准噶尔盆地克拉美丽气田火山岩岩电关系交会图