Results 31 to 40 of about 3,752,884 (240)

Case studies of ultrasonic full waveform inversion for inspecting concrete structures

e-Journal of Nondestructive Testing
The non-destructive evaluation of reinforced pre-stressed concrete structures is critical to prevent catastrophic failures of aging infrastructure. Conventional non-destructive inspection methods often rely on manual and subjective interpretation of the
David Sollberger, Chris Udell, Lion Krischer, Christian Boehm, Elmar Strobach, David Corbett   +5 more
doaj   +1 more source

Seismic Waveform Inversion Using the Finite-Difference Contrast Source Inversion Method

Journal of Applied Mathematics, 2014
This paper extends the finite-difference contrast source inversion method to reconstruct the mass density for two-dimensional elastic wave inversion in the framework of the full-waveform inversion.
Bo Han, Qinglong He, Yong Chen, Yixin Dou   +3 more
doaj   +1 more source

Constrained Full Waveform Inversion for Borehole Multicomponent Seismic Data

Geosciences, 2019
Full-waveform inversion for borehole seismic data is an ill-posed problem and constraining the problem is crucial. Constraints can be imposed on the data and model space through covariance matrices. Usually, they are set to a diagonal matrix.
Marwan Charara, Christophe Barnes
doaj   +1 more source

Progress and prospect of surface-wave imaging techniques in near-surface applications

地球与行星物理论评, 2022
Elastic properties of near-surface materials and their effects on seismic wave propagation are of fundamental interest in groundwater, engineering, and environmental studies. Shear-wave velocity is used to determine 'stiffness', one of the key properties
Limin Wang, Jianghai Xia, Yinhe Luo, Aifei Bian   +3 more
doaj   +1 more source

Parameterization Analysis in Elastic Full-Waveform Inversion of Multi-Component Seismic Data

, 2022
International audienceMain objectives This study analyses the influence of different model parameterizations in the elastic full-waveform inversion of multi-component ocean-bottom seismic data, so as to design an effective FWI workflow to reconstruct P ...
Métivier, Ludovic, Cao, Jian, Brossier, Romain   +2 more
core   +1 more source

Recent Advances in the GPR Detection of Grouting Defects behind Shield Tunnel Segments

Remote Sensing, 2021
Injecting grout into the gaps between tunnel shield segments and surrounding rocks can reduce ground subsidence and prevent ground water penetration. However, insufficient grouting and grouting defects may cause serious geological disasters.
Ming Peng, Dengyi Wang, Liu Liu, Zhenming Shi, Jian Shen, Fuan Ma   +5 more
doaj   +1 more source

Estimation of gas hydrate concentration from multi-component seismic data at sites on the continental margins of NW Svalbard and the Storegga region of Norway [PDF]

, 2008
High-resolution seismic experiments, employing arrays of closely spaced, four-component ocean-bottom seismic recorders, were conducted at a site off western Svalbard and a site on the northern margin of the Storegga slide, off Norway to investigate how ...
Mienert, J., Chand, S., Westbrook, Graham, Reston, Timothy J., Haacke, R. R., Gei, D., Carcione, JM, Dean, S, Mienert, Jürgen, Gei, D, Minshull, TA, Westbrook, G.K., Madrussani, G, Long, C, Reston, T.J., Westbrook, G. K., Flueh, E., Carcione, J.M., Peacock, S., Foucher, JP, Peacock, S, Bünz, S., Carcione, J. M., Flueh, E, Zillmer, Matthias, Zillmer, M, Camerlenghi, A, Rossi, G., Flueh, Ernst R., Chand, S, Foucher, J-P., Haacke, R.R., Minshull, T. A., Vanneste, M, Haacke, RR, Buenz, S, Minshull, T.A., Nouze, H, Camerlenghi, A., Dean, S., Nouzé, H., Rossi, G, Mienert, J, Reston, Timothy, Long, C., Vanneste, M., Foucher, J.-P., Madrussani, G., Zillmer, M.   +48 more
core   +1 more source

Elastic Wave Phase Inversion in the Local-Scale Frequency–Wavenumber Domain with Marine Towed Simultaneous Sources

Journal of Marine Science and Engineering
Elastic full waveform inversion (EFWI) is a crucial technique for retrieving high-resolution multi-parameter information. However, the lack of low-frequency components in seismic data may induce severe cycle-skipping phenomena in elastic full waveform ...
Shaobo Qu, Yong Hu, Xingguo Huang, Jingwei Fang, Zhihai Jiang   +4 more
doaj   +1 more source

Elastic full-waveform inversion for earthquake source parameters [PDF]

Geophysical Journal International, 1996
SUMMARY 2-D full-waveform inversion of double-couple earthquake sources is implemented. Temporally and spatially extended sources are represented by superposition of doublecouples. The source parameters solved for are the spatial location, origin time, amplitude and orientation of each double-couple.
Yafei Wu, George A. McMechan
openaire   +1 more source

A Magneto‐Mechanically Activated Nerve Guidance Conduit Promotes Peripheral Nerve Regeneration via TIMP1‐Mediated Membrane Tension Transfer

Advanced Functional Materials, EarlyView.
This study presents a magneto‐mechanical strategy that incorporates FP@MSCs into an aligned PCL/GelMA nerve guidance conduit. Magnetic stimulation increases membrane tension in FP@MSCs, triggering cytoskeletal remodeling, Schwann cell‐like differentiation, and TIMP1 secretion. TIMP1 activates ITGB1/CD63–FAK signaling in NE‐4C cells, increasing membrane
Xinyu Zhu, Yumin Wu, Xiang Gao, Tianlu Wang, Wanting Jia, Xueying Mei, Huanzhong Ji, Zongxi Wu, Yujie Liang, Xiang Li, Kan Li, Jingyuan Li, Guangsen Zheng, Guiqing Liao, Siyong Gao   +14 more
wiley   +1 more source