bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-resolution reflected P- and SH-wave imaging for the shallow subsurface in the thick Quaternary area
Authors: Wang Kai , Feng Xuan , Wang Xiaojiang , Yue Hangyu , Zhang Baowei 
Published: February 2021

Abstract
For the construction of urban underground space, the shallow stratum structure from surface to 200 meters needs to be high-precision investigated. As limited in the theoretical level, the normal reflection P-wave can’t image in the very shallow subsurface especially in a thick Quaternary area. The SH-wave survey has a higher resolution in the theoretical level because the SH-wave has a lower velocity and shorter wavelength. The aim of this paper is to present a combined seismic reflection survey of P- and SH-wave in a thick Quaternary area where is close to Xiong’an New Area. By using the (λ/4) criterion, we obtain a resolution around 1.4m and 2.4 m for the SH-wave section in 9 m (v=169 m/s and f=30 Hz) and 50 m (v=209 m/s and f=22 Hz) depth separately and a resolution around 3.8m for the P-wave section in 200 meters depth (v=1878 m/s and f=125 Hz).
Monitoring surface deformation of high-speed railway using time-series InSAR method in northeast China
Authors: Meng Zhiguo , Shu Chuanzeng , Wu Qiong , Yang Ying , Fu Zhe 
Published: February 2021

Abstract
It is difficult to monitor the surface deformation along the high-speed railway for the complexity of the surface texture in extensive region. In this paper, based on sentinel-1A /B data, the surface deformation along the high-speed railway from Fuyu to Dehui was tried to evaluate using time-series PS-InSAR method. The results indicate that the surface deformation is not dangerous for the safe operation of the railway. Moreover, the surface depression near Dehuixi station is potentially dangerous for the safety of the railway. Finally, the cause of the surface deformation along the railway is mainly attributed to the human activity and the seasonal subgrade frost heave in the seasonal frozen soil.
Research on the detection effect of microgravity method in urban mined-out area
Authors: Zhang Youan , Lu Lichun , Deng Guocheng , Quan Haoli , Zhang Pei , Zhang Chong 
Published: February 2021

Abstract
The mined-out area is a potential geological hazard for urban safety. In particular, there are many mined-out areas in the Longgui nitrate mine in Guangzhou, which poses a serious threat to the safety of large-scale buildings in the city. Therefore, it is necessary to find out its specific spatial distribution location and center depth information. The micro-gravity detection method uses the residual density inversion and the re-focus weighted inversion method to identify the spatial distribution of urban underground goaf by observing the weak change of gravity field in the area The microgravity detection method combined with the effective processing and inversion interpretation method can realize the delineation of the specific distribution range and spatial distribution form of the cave in the goaf.
The Research of HuiZhou Urban Active Fault Detection
Authors: Li Yuhui 
Published: February 2021

Abstract
With the rapid development of society and economy, the speed of urban construction is accelerating, social wealth is rapidly gathering and the population is high. The degree of concentration is obvious and the damage caused by urban earthquakes are obviously on the rise. Underground fault zone activity causes the culprit of an urban earthquake. The ground rupture caused by the earthquake is causing damage to buildings and people’s lives. This paper studies the activity of Huizhou urban active faults by comprehensive methods such as drilling, earthquake, chronology analysis, and sedimentary environment analysis. It is determined that the Huizhou fault is an early Quaternary fault and is currently not active.
Three dimensional reverse time migration on common offset GPR data for void imaging
Authors: Wang Honghua , Gong Junbo , Liang Zhihuan 
Published: February 2021

Abstract
Three dimensional (3D) Reverse time migration (RTM), as an indispensable imaging technique, has been widely applied to the observed seismic data imaging. However, the RTM of Ground Penetrating radar (GPR) is usually implemented in its two-dimensional (2D) from. This paper proposes a 3D RTM algorithm on common offset GPR data for void imaging. In this algorithm, the 3D finite difference time domain (FDTD) method is applied to calculate the backward extrapolation of electromagnetic fields. And the time zero imaging condition is applied to obtain the final RTM results. Comparisons of the imaging results of 3D and 2D RTM demonstrated that the 3D RTM imaging results were superior to those of 2D RTM. And 3D spatial distribution of Void can be imaged by the proposed 3D RTM algorithm with high accuracy, which can help the subsequent interpretation of GPR profile.
Frequency 3D slice image visualization for GPR applications
Authors: He Wenchao , Hao Tong , Ke Hainan 
Published: February 2021

Abstract
Ground Penetrating Radar (GPR) is an efficient tool for the detection of the underground utilities. However, most data collected by GPR are in the spatial/time domain, the information in frequency domain is sometimes neglected. Joint Time-frequency Analysis (JTFA) methods are widely used to deal with the problem. In this paper, we propose a further application based on JTFA method to re-construct the frequency 3D slice image visualization (frequency C-scan) to represent the distributions of the main frequency components of the surveying area. The experiments are conducted in our sandbox with a PVC pipe buried in. After employing the proposed signal processing flow, the frequency C-scan can be re-constructed. By segmenting the frequency C-scan, frequency distribution over a surface at particular radar time/depth can be obtained. The results exhibit the capability of the proposed method to show the spatial and frequency signatures of the buried objects at certain depth.
Roadbed defect detection from ground penetrating radar B-scan data using Faster RCNN
Authors: Fang Zheng , Shi Zhensheng , Wang Xiaokai , Chen Wenchao 
Published: February 2021

Abstract
Ground penetrating radar (GPR) is the main technical method to detect roadbed subgrade defect. The recognition of subgrade defect is still mainly based on manual interpretation, which requires high professional knowledge of interpreters, resulting in the demand for automatic detection technology. In this paper, a solution for automatic detection of roadbed defect by implementing Faster RCNN with GPR system is presented. We simulated 30000 roadbed defect GPR B-scan data by simulation software gprMax, labeled them appropriately and automatically. Specifically, Faster RCNN was chosen, as a compromise between accuracy and ease of comparison. Preliminary detection results show that the AP (Average Precision) is 0.8067, proving that our simulation for defect is reasonable and reliable. And the Faster RCNN trained on the simulation dataset without any actual data also has excellent performance on the actual GPR data. Our method of detecting defects automatically with CNN can be easily generalized to other GPR tasks, e.g., detecting pipe, horizon extraction. It’s the biggest open-source GPR B-scan dataset as far as we know. Our simulation dataset and trained model will be made available.
Modeling of near-surface structure and Response simulation of GPR in the Jezero crater, Mars
Authors: Zhang Ling , Zeng Zhaofa , Xu Yi 
Published: February 2021

AbstractNASA’s upcoming Mars 2020 will carry Ground Penetrating Radar (GPR) named RIMFAX to Mars for exploration. Mars 2020 will land at Jezero crater, located to the northwest of the Isidis basin. The landing site experienced series of geological processes such as delta formation, lavas coverage and surface weathering. Establishing the electromagnetic model here, which is used for forward simulation of RIMFAX will help the later data processing and interpretation. This paper considers the interface fluctuations, the randomness of the background medium, and the randomness of the cracks to establish a Mars near-surface electrical model, and performs forward result based on the parameters of RIMFAX. The research will support the later data processing and interpretation.
A High-resolution GPR horizon extraction method based on local reflection and global correlation
Authors: Zhu Dongyi , Shi Zhensheng , Wang Xiaokai , Chen Wenchao 
Published: February 2021

Abstract
Horizon extraction is a very basic and important part of ground penetrating radar (GPR) interpretation. Most GPR horizon extraction methods are based on local reflection of the GPR event such as the trace correlation algorithm, and hidden Markov model algorithm. These methods use only local structural characteristics of the GPR data and often fail to pick the layer correctly across discontinuous caused by faults and noise. In order to overcome shortcomings of the above methods, a novel method based on gradient structure tensor algorithm (GST) and dynamic time warping algorithm (DTW) is used in this paper to extract the horizon accurately which has been proved to be effective in the complex seismic data. GPR electromagnetic wave and seismic wave have certain similarity in kinematics and dynamics, we apply this method to realistic GPR data and prove its effectiveness.
Experimental study on the refinement detection at the bottom of foundation pit used by GPR in the strong interference environment
Authors: Li Yaohua , Li Xu 
Published: February 2021

Abstract
Due to the refraction of the detection environment and conditions, the electromagnetic waves emitted by the ground penetrating radar are susceptible to interference from external factors. The received reflected waves often have the characteristics of “weak signals and strong interference”, resulting in low sensitivity and low signal-to-noise in the collected data. Resolution tolerances cause difficulties in data interpretation. Based on the uniqueness characteristics of spectral response for the single medium, and the differences of energy intensity between effective signal and interference signal, the spectrum energy intensity analysis is introduced into signal processing in this article, the spectral response feature of different target mediums have been extract from the signal of radar reflected wave, the spectral energy strength about the underground target medium has been calculated, and the geological distribution feature of underground soil has been inversed according to three-dimensional reconstruction technology in further. It showed that this data processing method proposed in this article can remove interference and preserve effective signal which even weak and deep at the same time by the detection and application effect in the strong interference environment at the bottom of construction foundation pit, the interpretation accuracy of ground penetrating radar had improved and the purpose of refinement data processing had achieved.
Targets Imaging Method for A New MIMO Through-wall Radar
Authors: Cheng Dandan , Zeng Zhaofa , Hu Zhipeng , Kang Xiaoqian 
Published: February 2021

Abstract
The ultra-wideband (UWB) multi-input multi-output (MIMO) radar technique is playing a more and more important role in the application of through-wall detection because of its high resolution, lower antenna requirements, and efficient data capturing ability. A new UWB MIMO sparse array radar system with eight pairs of transmitting and receiving miniaturized Vivaldi antennas is designed in this paper and reverse time migration of the acoustic wave equation based on finite difference is used for target imaging. How to locate the target and reconstruct velocity model is the key in this paper. Finally, we found that this processing method is completely effective for forward single-target imaging, but there is still a lot of research space, and if we want to apply them in practice, further study must be done.
Stratification of Lunar Regolith Based on Attribute Analysis
Authors: Cheng Siyuan , Zhang Ling , Jia Zhuo , Zhao Xueran , Lu Qi , Liu Sixin 
Published: February 2021

Abstract
On December 14, 2013, China’s Chang ’e-3 missions landed on the lunar surface, providing valuable information for better study of the moon. LPR (Lunar penetrating radar) is a very important and effective detection method. The lunar surface shallow radar data we obtained through the lunar exploration radar can be used to understand the geological structure of the lunar surface and the thickness of the lunar regolith. This paper analyzes the processed LPR data of “Chang’e-3” by using instantaneous attributes, and obtains the instantaneous amplitude attributes, instantaneous phase attributes, and instantaneous frequency attributes of the radar profile. According to the results of the instantaneous attribute analysis, the lunar regolith structure of the radar profile is divided, and it is found that it can be well matched with the previous research results.
PCA applied to Data Fusion for Subsurface Target Imaging of Full-polarimetric GPR
Authors: Xue Cewen , Feng Xuan , Zhou Haoqiu , Li Xiaotian , Liang Wenjing , Wang Ying 
Published: February 2021

Abstract
Full-polarimetric ground penetrating radar (GPR) can obtain more comprehensive polarization data (called VV, HH, VH) for the same target than traditional commercial radar (only VV). We need to use data fusion technology to combine the polarization information of the three different polarization modes. However, the full-polarimetric GPR data fusion method has one weighted average fusion, which will mask the advantages of full polarization. Principal component analysis (PCA) is a technology of data dimensionality reduction and compression which can use VV, HH and VH as a three-dimensional data to conduct data dimensionality reduction and find the best data fusion results. In order to check the reliability, we obtained the full-polarimetric GPR data of three typical targets in the laboratory for analysis. Then we compare PCA with the weighted average fusion method by using the instantaneous amplitude and conclude that PCA can fuse full-polarimetric GPR data better than weighted average fusion.
GPR attribute analysis for the detection of LNAPL contaminated soils
Authors: Lu Qi , Wang Yan , Li Hongli 
Published: February 2021

Abstract
Light non-aqueous phase liquids (LNAPL) are hydrocarbons, immiscible in water and less dense than water. This paper uses GPR attribute analysis to evaluate the LNAPL contaminated soils. A GPR experiment for LNAPL leakage in a sand box is set up in the laboratory. After GPR data processing, three types of attributes are calculated. The instantaneous amplitude attribute describes the LNAPL pollution range even though the difference of electromagnetic properties is small between the target and the surrounding media. The similarity attribute delineates the boundary of LNAPL contaminated area based on the variations of the media through calculating the similarity of the adjacent traces’ waveforms and amplitude. The energy attribute helps to determine the source point of LNAPL leakage in recent LNAPL leakages. We believe that the GPR attribute analysis has a great potential to improve the interpretation of the GPR detection at actual LNAPL contaminated sites.
Three-Dimensional Inversion of Controlled-Source Electromagnetic Data in Fanchang Region, Anhui Province
Authors: Zhou Zikun , Wang Xueqiu , Yin Jian , Zhang Jinhui , Weng Aihua , Wang Tianqi 
Published: February 2021

Abstract
Fanchang area of Anhui Province is an important link in the middle and lower reaches of the Yangtze River. To study the distribution of rock mass near the surface of the area and the contact relationship between the strata, and to determine the possible ore body space, we carry out a 15km controlled-source electromagnetic(CSEM) survey. The observed data is the electric field amplitude data simulating wide-area electromagnetic. For the single-section electric field amplitude data of controlled source, because of the lack of magnetic field data, the impedance data needed for audio geomagnetic inversion cannot be formed. This paper uses the limited memory quasi-Newton(L-BFGS) method to perform a three-dimensional inversion with the source directly. The theoretical model test results show that the inversion method can recover the underground resistivity structure and obtain better anomalous body resolution. The three-dimensional inversion of the CSEM data in Fanchang area shows that we could get the best inversion results when the grid size is about 1/3~1/2 of the dot pitch, the background resistivity is 100 Ω·m, and the error level is 5%. The inversion result of the full-section data, including two sources, shows that the south and north end of the profile is high-resistivity, and the intermediate resistivity is low. However, in the middle of the profile, the resistivity is significantly higher than the two sides. Combined with geological data, this change reflects the distribution of strata/rock masses on the surface of the work area and the contact relationship between them. This consistency verifies the feasibility and necessity of three-dimensional source inversion for the CSEM field amplitude |Ex| data of multi-source and single profile. The underground three-dimensional resistivity structure can be effectively obtained by using the L-BFGS method with the controlled source.
Comparative Analysis on Multimode Sensitivity Kernels of Rayleigh Wave Based on Adjoint Method
Authors: Yao Yongkang , Zhang Yu , Cai Jianfeng , Zhang Shuangxi 
Published: February 2021

Abstract
Different modes of surface waves possess different phase velocities for each wavelength, which reflects the layer information of different depths. Penetrating depth of surface wave data is significant to determine stratigraphic models and invert their velocity structures. Instead of ray theory, we use the sensitivity kernels to investigate the relationship between multimode wavelengths and penetrating depth for a layered model based on the adjoint wave equation. We use linear Radon transform to perform Rayleigh-wave multimode separation and reconstruction. The results confirm that longer wavelength components are sensitive to deeper layers. Different modes of surface waves are sensitive to different depths. The kernels in HVL (high-velocity-layer model) and LVL (low-velocity-layer model) suggest that the velocity anomaly layer has a shielding effect on sensitivity penetrating. Rayleigh waves are insensitive to the layers beneath a velocity anomaly layer and the HVL itself.
Application of In-situ Stress Calculation in Engineering
Authors: Wang Shengao , Han Fuxing , Bing Qi 
Published: February 2021

Abstract
In-situ stress is an important factor affecting the stability of underground structure and the main driving force of oil and gas migration in underground. It is of great significance to the implementation of engineering, the exploitation of oil and gas and the guarantee of safety. Therefore, through the analysis of logging curves, the relevant rock mechanical parameters are extracted, then a layered model is established to calculate the ground stress and evaluate the stability of the surrounding rock. The in-situ stress obtained by parameter extraction also plays a guiding role in oil and gas exploitation and drilling target implementation.
An Automated Segment Selection Algorithm Based on the Assessment of Surface Wave Characteristic in Ambient Noise Recordings
Authors: Liu Ya , Xia Jianghai , Dai Tianyu , Xi Chaoqiang , Ning Ling , Xing Huaixue , Chang Xiaojun 
Published: February 2021

Abstract
Passive surface wave methods have been widely used to reconstruct velocity structures on different scales. The methods are becoming increasingly popular in urban areas because of the urgent needs of urban development. Unlike years of recordings on continental scales, the duration of recordings in urban areas usually lasts only for hours, even minutes. Thanks to huge amounts of cultural noise, especially from traffic, passive surface wave methods have proved their efficiency in urban areas, even with relatively short-time recordings. However, data needs to be processed more carefully for obtaining valuable information with limited recordings. Based on the characteristic of surface waves in − domain, we propose a formula to assess the intensity of surface waves in a linear array, thereby forming an automated data selection algorithm by selecting those segments with energetic surface waves. Results of a real-world example demonstrated the procedures of the proposed algorithm, and its effectiveness and reliability are therefore validated.
A Comparative Study on the Exploration Depth and Resolution of Winner and Schlenberg Methods Based on Potential, Current and Field Fields
Authors: Mu Qian , Liu Lijia , Han Jiangtao 
Published: February 2021

Abstract
High-density electrical method is widely used in hydrology, engineering, environment, and other fields. It is of great practical significance to study its exploration depth and resolution. The traditional theoretical research is to analyze and explore the exploration depth and resolution through the current density. Based on the theory of field theory, this paper proposes to study the depth and resolution of high-density electrical exploration based on a stable DC electric field. First, the derivation of the three field quantities of potential, current, and field lines in the normal field was completed, and related numerical simulation calculations were realized. Through theoretical model calculation and analysis, qualitative comparison conclusions of the two methods of Winner and Schlumberger are obtained. It is believed that the detection depth and resolution of the Winner method are lower than those of the Schlumberger, but the observation accuracy of the Winner method is higher than the Schlumberger method. Furthermore, the reliability of this conclusion is verified by physical model experiments. At the same time, the feasibility of the research on exploration depth and resolution based on the three electric field components of potential, current, and field lines is also proved.
Bidirectional Angle Limited Shortest Path Ray Tracing in Complex Topographical Conditions
Authors: Bing Qi , Sun Zhangqing , Wang Shengao 
Published: February 2021

Abstract
Ray tracing technology in complex topographical conditions has an important influence on mountain velocity modeling and migration imaging. In order to realize the stable and high precision ray tracing in the conditions, the bidirectional angle limited shortest path ray tracing method with under the condition of irregular calculation boundary is proposed. Firstly, based on the shortest path ray-tracing method, a new algorithm of local traveltime is given under the condition of bidirectional angle limited. Secondly, combining this algorithm with narrowband technology, a ray-tracing algorithm is proposed to adapt to arbitrary complex terrain; Then, we compare the accuracy of this method and the first-order finite-difference method; Finally, the adaptability and stability of the complex surface are verified by the calculation example, and the corresponding conclusions are given.
Numerical Analysis of Distributed Acoustic Sensing Data Full-waveform Inversion
Authors: Liu Hui , Li Jing 
Published: February 2021

Abstract
Distributed Acoustic Sensing (DAS) is a new type of seismic technique developed rapidly in recent years. Compared with conventional geophones, DAS receives strain rate signals with a continuous density survey. It has the advantages of low cost, high resolution, and wide application range. This abstract uses the elastic wave finite-difference method to simulate the DAS signal response and analyze surface wave dispersion characteristics. Then, we carry out 1-D dispersion curve inversion and revised 2-D DAS full-waveform inversion (FWI) tests on the DAS data under different gauge length conditions. The results show that our proposed DAS 1D dispersion inversion and 2D FWI method can provide a reliable velocity inversion result similar to conventional geophone data.