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Frontiers of Structural and Civil Engineering 2024年第3期18卷 365-379页

作者： Bohao WANG Wei WANG Feng JIN handong tan Ning LIU Duruo HUANG State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China Institute of Science and Technology China Three Gorges CorporationBeijing 100038China School of Geophysics and Information Technology China University of GeosciencesBeijing 100083China

This study investigated the application of electrical resistance tomography(ERT)in characterizing the slurry spatial distribution in cemented granular materials(CGMs).For CGM formed by self-flow grouting,the voids in the accumulation are only partially filled and the bond strength is often limited,which results in difficulty in obtaining in situ samples for quality ***,it is usually infeasible to evaluate the grouting effect or monitor the slurry spatial distribution by a mechanical *** this research,the process of grouting cement paste into high alumina ceramic beads(HACB)accumulation is reliably monitored with *** shows that ERT results can be used to calculate the cement paste volume in the HACB accumulation,based on calibrating the saturation exponent n in Archie’s *** results support the feasibility of ERT as an imaging tool in CGM characterization and may provide guidance for engineering applications in the future.

关键词： electrical resistance tomography cemented granular material grouting spatial distribution Archie’s law

The parallel 3D magnetotelluric forward modeling algorithm

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Applied Geophysics 2006年第4期3卷 197-202页

作者： tan handong Tong Tuo Lin Changhong State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083China School of Geophysics and Information Technology China University of Geosciences Beijing 100083 China

The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the data in the frequency domain, which is very suitable for parallel computation. With the advantage of MPI and based on an analysis of the flow of the 3D magnetotelluric serial forward algorithm, we suggest the idea of parallel computation and apply it. Three theoretical models are tested and the execution efficiency is compared in different situations. The results indicate that the parallel 3D forward modeling computation is correct and the efficiency is greatly improved. This method is suitable for large size geophysical computations.

关键词： Magnetotelluric 3D forward modeling MPI parallel programming design 3D staggered-grid finite difference method parallel algorithm.

基于位移逆Krylov子空间的全波形航空瞬变电磁法三维数值模拟和响应特征

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现代地质 2023年第1期37卷 74-83页

作者：董岩谭捍东付兴中国地质大学(北京)地球物理与信息技术学院北京100083

为了研究复杂地电模型的航空瞬变电磁法全波形响应特征,需要开发考虑发射波形的三维数值模拟算法。本研究基于非结构四面体网格和位移逆Krylov子空间(Shift-and-Invert Krylov,简称SAI Krylov)方法,采用基于电偶极子离散的场源处理方法... 详细信息

为了研究复杂地电模型的航空瞬变电磁法全波形响应特征,需要开发考虑发射波形的三维数值模拟算法。本研究基于非结构四面体网格和位移逆Krylov子空间(Shift-and-Invert Krylov,简称SAI Krylov)方法,采用基于电偶极子离散的场源处理方法模拟场源,在时间域进行计算实现了全波形航空瞬变电磁法矢量有限元三维数值模拟。使用均匀半空间模型在阶跃波、半正弦波、三角波和梯形波激发下的全波形解析解、VTEM实际激发波形的后推欧拉算法计算结果,检验了本研究开发的数值模拟算法的正确性。设计地表起伏异常体模型,计算和分析了航空瞬变电磁响应特征。开发的基于位移逆Krylov子空间的全波形航空瞬变电磁法三维数值模拟算法适合模拟复杂地电模型的响应,具有较高的计算精度。

关键词：航空瞬变电磁法三维正演全波形位移逆Krylov子空间矢量有限元

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时移可控源音频大地电磁法三维反演研究

现代地质 2023年第1期37卷 90-98页

作者：胡琪璇谭捍东于翠中国地质大学(北京)地球物理与信息技术学院北京100083

时移地球物理监测是观测地下物性参数随时间动态变化的有效方法。地球物理反演结果会受到测量误差、测量环境的噪声污染以及地球物理反演多解性等系统性因素的影响。如果对时移地球物理数据进行不同时刻数据的单独反演,可能会导致不同... 详细信息

时移地球物理监测是观测地下物性参数随时间动态变化的有效方法。地球物理反演结果会受到测量误差、测量环境的噪声污染以及地球物理反演多解性等系统性因素的影响。如果对时移地球物理数据进行不同时刻数据的单独反演,可能会导致不同时刻的反演结果可对比性差,从而影响时移地球物理的监测效果。针对可控源音频大地电磁法在监测领域的实际需求,将不同时刻的观测数据放在一起反演,不同时刻的电阻率模型相互约束,实现了时移可控源音频大地电磁法三维反演。设计三种类型模型进行合成数据的单独反演和时移反演对比试算,验证了时移反演算法的有效性。反演结果表明:通过加入相邻时刻模型约束,时移反演可以更好地聚焦异常体的位置,降低噪声以及测量环境变化对反演结果的影响,防止反演伪影掩盖真实的地下变化。研究成果为时移可控源音频大地电磁法的实际应用奠定了良好基础。

关键词：时移可控源音频大地电磁法有限内存拟牛顿反演时移约束

Seasonal Variation of Hearing Sensitivity in the Red-eared Slider(Trachemys scripta elegans)

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Asian Herpetological Research 2024年第2期15卷 82-89页

作者： Tongliang WANG Jinxia YANG handong LI Jinhong LEI Haitao SHI Jichao WANG Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158HainanChina

Seasonal variation of hearing sensitivity has been observed in many vertebrate groups with obvious vocal *** hormones,conspecific calling signals,and temperature are potential factors that drive these plasticity *** have a hearing range that appears to be limited to under 1.5 kHz and are often thought to be non-vocal;thus,they are commonly neglected in vocal communication *** this study,we aimed to determine whether the auditory phenotype exhibits seasonal variation in sensitivity and to analyze the potential factors driving such variation patterns in *** measured hearing sensitivity and sex hormone levels in female(estradiol)and male(testosterone and dihydrotestosterone)Red-eared sliders(Trachemys scripta elegans)during spring and *** results showed that auditory brainstem response(ABR)thresholds were significantly lower in spring than in winter at a frequency range of 0.5-0.9 *** hearing-sensitivity bandwidth was wider,and the ABR latency was significantly shorter in spring than in *** significant differences were found in estradiol,testosterone,and dihydrotestosterone levels in *** elegans between spring and *** study is the first to reveal the seasonal variation of peripheral hearing sensitivity in turtles,a special animal group with limited hearing range and less *** variations may be used to explain these seasonal effects,but further research is required to confirm our findings.

关键词： auditory plasticity seasonal variation temperature turtles

基于物性参数梯度累加约束的电阻率法和重力勘探数据二维联合反演

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地球物理学进展 2023年第1期38卷 171-184页

作者：陈卓谭捍东彭淼中国地质大学(北京)地球物理与信息技术学院北京100083

对不同地球物理方法的数据进行联合反演,通过模型参数的相互约束可以减小反演的多解性.本文对电阻率法和重力勘探数据开展了基于电阻率和剩余密度梯度累加约束的二维联合反演研究.电阻率法采用数据空间Occam反演,重力勘探采用基于对数... 详细信息

对不同地球物理方法的数据进行联合反演,通过模型参数的相互约束可以减小反演的多解性.本文对电阻率法和重力勘探数据开展了基于电阻率和剩余密度梯度累加约束的二维联合反演研究.电阻率法采用数据空间Occam反演,重力勘探采用基于对数障碍法的正则化反演.通过在电阻率法和重力勘探反演的目标函数中引入电阻率和剩余密度梯度累加约束项,利用交替迭代方式实现了电阻率法和重力勘探数据的二维联合反演.对理论模型合成数据进行了单方法反演和联合反演,对比了反演效果.结果表明:联合反演结果优于单方法反演结果,联合反演结果对异常体的物性值恢复和形态刻画效果更好.

关键词：电阻率法重力勘探二维联合反演物性参数梯度累加约束

Parallel rapid relaxation inversion of 3D magnetotelluric data

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Applied Geophysics 2009年第1期6卷 77-83,104页

作者：林昌洪谭捍东佟拓中国地质大学地质过程与矿产资源国家重点实验室北京100083 中国地质大学(北京)地球物理与信息技术学院北京100083

We implement a parallel algorithm with the advantage of MPI （Message Passing Interface） to speed up the rapid relaxation inversion for 3D magnetotelluric data. We test the parallel rapid relaxation algorithm with synthetic and real data. The execution efficiency of the algorithm for several different situations is also compared. The results indicate that the parallel rapid relaxation algorithm for 3D magnetotelluric inversion is effective. This parallel algorithm implemented on a common PC promotes the practical application of 3D magnetotelluric inversion and can be suitable for the other geophysical 3D modeling and inversion.

关键词： Magnetotelluric MPI 3D rapid relaxation inversion parallel algorithm

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基于乘积型目标函数的电阻率法三维反演

现代地质 2023年第1期37卷 67-73页

作者：谢海军谭捍东马逢群中国地质大学(北京)地球物理与信息技术学院北京100083

为了减小地球物理反演的多解性,通常采用累加型目标函数,即数据拟合差项加上正则化项。基于累加型目标函数的反演存在如何优选正则化因子的问题,这个过程通常需要做大量的反演计算。本研究系统分析和实现了基于乘积型目标函数(数据拟合... 详细信息

为了减小地球物理反演的多解性,通常采用累加型目标函数,即数据拟合差项加上正则化项。基于累加型目标函数的反演存在如何优选正则化因子的问题,这个过程通常需要做大量的反演计算。本研究系统分析和实现了基于乘积型目标函数(数据拟合差项和正则化项相乘)的电阻率法三维反演,乘积型目标函数的反演不存在优选正则化因子的问题。三维正演采用非结构化有限单元法,三维反演采用有限内存拟牛顿方法。使用理论模型合成数据进行了三维反演,检验了基于乘积型目标函数的电阻率法三维反演的可行性与有效性。反演算例结果表明:基于乘积型目标函数的反演方法能够可靠恢复异常体的电阻率值、形态和位置。

关键词：电阻率法正则化乘积型目标函数三维反演

Three-dimensional conjugate gradient inversion of magnetotelluric sounding data

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Applied Geophysics 2008年第4期5卷 314-321页

作者：林昌洪谭捍东佟拓中国地质大学(北京)地球物理与信息技术学院北京100083

Based on the analysis of the conjugate gradient algorithm, we implement a threedimensional （3D） conjugate gradient inversion algorithm with magnetotelluric impedance data. During the inversion process, the 3D conjugate gradient inversion algorithm doesn＇ t need to compute and store the Jacobian matrix but directly updates the model from the computation of the Jacobian matrix. Requiring only one forward and four pseudo-forward modeling applications per frequency to produce the model update at each iteration, this algorithm efficiently reduces the computation of the inversion. From a trial inversion with synthetic magnetotelluric data, the validity and stability of the 3D conjugate gradient inversion algorithm is verified.

关键词： magnetotelluric 3D inversion conjugate gradient

Anomalous phenomena in DC–ULF geomagnetic daily variation registered three days before the 12 May 2008 Wenchuan M_S 8.0 earthquake

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Earth and Planetary Physics 2019年第4期3卷 330-341页

作者： Mei Li Li Yao YaLi Wang Michel Parrot Masashi Hayakawa Jun Lu handong tan Tao Xie China Earthquake Networks Center China Earthquake Administration Beijing 100045 China Laboratoire de Physique et Chimie de l’Environnement et de l’Espace Université d’Orléans CNRS Orléans France Hayakawa Institute of Seismo Electromagnetics Co. Ltd. University of Electro–Communications (UEC) Chofu Japan UEC Advanced Wireless Communications Research Center Chofu Japan School of Geophysics and Information Technology China University of Geosciences Beijing 100083 China

The hourly data of the vertical Z and the horizontal H components of 37 ground-based DC-ULF geomagnetic stations are examined during 20 April-12 May 2008. On 9 May 2008, three days before the Wenchuan MS 8.0 shock, anomalies-a double low-point and a decreased amplitude-are registered on the curves of the Z component at 25 stations in a large-scale area surrounding the Wenchuan epicentral area. The H component shows none of the double low-point phenomenon but does exhibit a reduced magnitude at the same time. The geomagnetic index Kp is also examined and indicates that the anomalies appear at a solar quiet period. The appearing time shift(Tzs) between the first low-point on May 9 and the minimum point occurring time of May 1-5, 2008 is also *** results show that Tzs is on the order of 1-2 hours earlier or later than usual and there is a 2-6 hours’ gap between these two lowpoints. However, there is still a transition area which includes the epicenter where Tzs=0. Variation amplitude examined on vertical Z increases as the distance from the epicenter decreases. An Earth-air-ionosphere model has been employed to investigate a possible mechanism of this phenomenon and positive results have been unexpectedly attained. All these above-related results tend to prove that the variations of the Z and H on May 9, 2008 during the solar quiet period are probably associated with the forthcoming Wenchuan MS 8.0 earthquake.

关键词： Wenchuan MS 8.0 earthquake geomagnetic abnormity spatial variations Earth-air-ionosphere model