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InSAR-derived surface deformation characteristics and mining subsidence parameters in mountain coal mines
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作者 JIANG Xiaowei SHI Wenbing +2 位作者 LIANG Feng GUI Jingjing LI Jiawei 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3139-3156,共18页
Mining-induced surface deformation disrupts ecological balance and impedes economic progress.This study employs SBAS-InSAR with 107-view of ascending and descending SAR data from Sentinel-1,spanning February 2017 to S... Mining-induced surface deformation disrupts ecological balance and impedes economic progress.This study employs SBAS-InSAR with 107-view of ascending and descending SAR data from Sentinel-1,spanning February 2017 to September 2020,to monitor surface deformation in the Fa’er Coal Mine,Guizhou Province.Analysis on the surface deformation time series reveals the relationship between underground mining and surface shifts.Considering geological conditions,mining activities,duration,and ranges,the study determines surface movement parameters for the coal mine.It asserts that mining depth significantly influences surface movement parameters in mountainous mining areas.Increasing mining depth elevates the strike movement angle on the deeper side of the burial depth by 22.84°,while decreasing by 7.74°on the shallower side.Uphill movement angles decrease by 4.06°,while downhill movement angles increase by 15.71°.This emphasizes the technology's suitability for local mining design,which lays the groundwork for resource development,disaster prevention,and ecological protection in analogous contexts. 展开更多
关键词 Time-series InSAR surface deformation Subsurface mining Mining subsidence
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Calculating real-time surface deformation for large active surface radio antennas using a graph neural network
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作者 Zihan Zhang Qian Ye +2 位作者 Li Fu Qinghui Liu Guoxiang Meng 《Astronomical Techniques and Instruments》 CSCD 2024年第5期267-274,共8页
This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible f... This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible for gravitational deformation but not for temperature-induced deformation.The introduction of this method facilitates real-time calculation of deformation caused both by gravity and temperature.Constructing the surrogate model involves two key steps.First,the gravitational and thermal loads are encoded,which facilitates more efficient learning for the neural network.This is followed by employing a graph neural network as an end-to-end model.This model effectively maps external loads to deformation while preserving the spatial correlations between nodes.Simulation results affirm that the proposed method can successfully estimate the surface deformation of the main reflector in real-time and can deliver results that are practically indistinguishable from those obtained using finite element analysis.We also compare the proposed surrogate model method with the out-of-focus holography method and yield similar results. 展开更多
关键词 Large radio telescope surface deformation Surrogate model Graph neural network
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Embedded System Development for Detection of Railway Track Surface Deformation Using Contour Feature Algorithm 被引量:1
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作者 Tarique Rafique Memon Tayab Din Memon +1 位作者 Imtiaz Hussain Kalwar Bhawani Shankar Chowdhry 《Computers, Materials & Continua》 SCIE EI 2023年第5期2461-2477,共17页
Derailment of trains is not unusual all around the world,especially in developing countries,due to unidentified track or rolling stock faults that cause massive casualties each year.For this purpose,a proper condition... Derailment of trains is not unusual all around the world,especially in developing countries,due to unidentified track or rolling stock faults that cause massive casualties each year.For this purpose,a proper condition monitoring system is essential to avoid accidents and heavy losses.Generally,the detection and classification of railway track surface faults in real-time requires massive computational processing and memory resources and is prone to a noisy environment.Therefore,in this paper,we present the development of a novel embedded system prototype for condition monitoring of railway track.The proposed prototype system works in real-time by acquiring railway track surface images and performing two tasks a)detect deformation(i.e.,faults)like squats,shelling,and spalling using the contour feature algorithm and b)the vibration signature on that faulty spot by synchronizing acceleration and image data.A new illumination scheme is also proposed to avoid the sunlight reflection that badly affects the image acquisition process.The contour detection algorithm is applied here to detect the uneven shapes and discontinuities in the geometrical structure of the railway track surface,which ultimately detects unhealthy regions.It works by converting Red,Green,and Blue(RGB)images into binary images,which distinguishes the unhealthy regions by making them white color while the healthy regions in black color.We have used the multiprocessing technique to overcome the massive processing and memory issues.This embedded system is developed on Raspberry Pi by interfacing a vision camera,an accelerometer,a proximity sensor,and a Global Positioning System(GPS)sensors(i.e.,multi-sensors).The developed embedded system prototype is tested in real-time onsite by installing it on a Railway Inspection Trolley(RIT),which runs at an average speed of 15 km/h.The functional verification of the proposed system is done successfully by detecting and recording the various railway track surface faults.An unhealthy frame’s onsite detection processing time was recorded at approximately 25.6ms.The proposed system can synchronize the acceleration data on specific railway track deformation.The proposed novel embedded system may be beneficial for detecting faults to overcome the conventional manual railway track condition monitoring,which is still being practiced in various developing or underdeveloped countries. 展开更多
关键词 Railway track surface faults condition monitoring system fault detection contour detection deep learning image processing rail wheel impact
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Effect of longwall-induced subsurface deformations on shale gas well casing stability under deep covers 被引量:1
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作者 Daniel W.H.Su Peter Zhang +1 位作者 Mark Van Dyke Todd Minoski 《International Journal of Mining Science and Technology》 EI CSCD 2019年第1期3-8,共6页
This paper presents the results of a 2017 study conducted by the National Institute for Occupational Safety and Health(NIOSH), Pittsburgh Mining Research Division(PMRD), to evaluate the effects of longwall-induced sub... This paper presents the results of a 2017 study conducted by the National Institute for Occupational Safety and Health(NIOSH), Pittsburgh Mining Research Division(PMRD), to evaluate the effects of longwall-induced subsurface deformations within a longwall abutment pillar under deep cover. The 2017 study was conducted in a southwestern Pennsylvania coal mine, which extracts 457 m-wide longwall panels under 361 m of cover. One 198 m-deep, in-place inclinometer monitoring well was drilled and installed over a 45 m by 84 m center abutment pillar. In addition to the monitoring well, surface subsidence measurements and underground coal pillar pressure measurements were conducted as the 457 m-wide longwall panel on the south side of the abutment pillar was being mined. Prior to the first longwall excavation, a number of simulations using FLAC3D^(TM) were conducted to estimate surface subsidence, increases in underground coal pillar pressure, and subsurface horizontal displacements in the monitoring well. Comparisons of the pre-mining FLAC3D simulation results and the surface, subsurface,and underground instrumentation results show that the measured in-place inclinometer casing deformations are in reasonable agreement with those predicted by the 3D finite difference models. The measured surface subsidence and pillar pressure are in excellent agreement with those predicted by the 3D models.Results from this 2017 research clearly indicate that, under deep cover, the measured horizontal displacements within the abutment pillar are approximately one order of magnitude smaller than those measured in a 2014 study under medium cover. 展开更多
关键词 LONGWALL deformations SHALE gas WELLS CASING Safety and HEALTH
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Deformation,structure and potential hazard of a landslide based on InSAR in Banbar county,Xizang(Tibet)
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作者 Guan-hua Zhao Heng-xing Lan +4 位作者 Hui-yong Yin Lang-ping Li Alexander Strom Wei-feng Sun Chao-yang Tian 《China Geology》 CAS CSCD 2024年第2期203-221,共19页
The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan P... The Tibetan Plateau is characterized by complex geological conditions and a relatively fragile ecological environment.In recent years,there has been continuous development and increased human activity in the Tibetan Plateau region,leading to a rising risk of landslides.The landslide in Banbar County,Xizang(Tibet),have been perturbed by ongoing disturbances from human engineering activities,making it susceptible to instability and displaying distinct features.In this study,small baseline subset synthetic aperture radar interferometry(SBAS-InSAR)technology is used to obtain the Line of Sight(LOS)deformation velocity field in the study area,and then the slope-orientation deformation field of the landslide is obtained according to the spatial geometric relationship between the satellite’s LOS direction and the landslide.Subsequently,the landslide thickness is inverted by applying the mass conservation criterion.The results show that the movement area of the landslide is about 6.57×10^(4)m^(2),and the landslide volume is about 1.45×10^(6)m^(3).The maximum estimated thickness and average thickness of the landslide are 39 m and 22 m,respectively.The thickness estimation results align with the findings from on-site investigation,indicating the applicability of this method to large-scale earth slides.The deformation rate of the landslide exhibits a notable correlation with temperature variations,with rainfall playing a supportive role in the deformation process and displaying a certain lag.Human activities exert the most substantial influence on the spatial heterogeneity of landslide deformation,leading to the direct impact of several prominent deformation areas due to human interventions.Simultaneously,utilizing the long short-term memory(LSTM)model to predict landslide displacement,and the forecast results demonstrate the effectiveness of the LSTM model in predicting landslides that are in a continuous development and movement phase.The landslide is still active,and based on the spatial heterogeneity of landslide deformation,new recommendations have been proposed for the future management of the landslide in order to mitigate potential hazards associated with landslide instability. 展开更多
关键词 LANDSLIDE INSAR Human activity deformation STRUCTURE LSTM model Engineering construction Thickness Neural network Machine learning Prediction and prevention Tibetan Plateau Geological hazards survey engineering
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A Laplacian Surface Deformation and Optimization Based 3D Registration Algorithm for Image Guided Prostate Radiotherapy
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作者 Jinghao Zhou Shaoting Zhang +5 位作者 Sung Kim Salma Jabbour Sharad Goyal Bruce Haffty Dimitris Metaxas Ning J. Yue 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2012年第2期40-49,共10页
Purpose: To develop a fast landmark-based deformable registration method to capture the soft tissue transformation between the planning 3D CT images and treatment 3D cone-beam CT (CBCT) images for the adaptive externa... Purpose: To develop a fast landmark-based deformable registration method to capture the soft tissue transformation between the planning 3D CT images and treatment 3D cone-beam CT (CBCT) images for the adaptive external beam radiotherapy (EBRT). Method and Materials: The developed method was based on a global-to-local landmark-based deformable registration algorithm. The landmarks were first acquired by applying a fast segmentation method using the active shape model. The global registration method was applied to establish a registration framework. The Laplacian surface deformation (LSD) and Laplacian surface optimization (LSO) method were then employed for local deformation and remeshing respectively to reach an optimal registration solution. In LSD, the deformed mesh is generated by minimizing the quadratic energy to keep the shape and to move control points to the target position. In LSO, a mesh is reconstructed by minimizing the quadratic energy to smooth the object by minimizing the difference while keeping the landmarks unchanged. The method was applied on 8 EBRT prostate datasets. The distance and volume based estimators were used to evaluate the results. The target volumes delineated by physicians were used as gold standards in the evaluation. Results: The entire segmentation and registration processing time was within 1 minute for all the datasets. The mean distance estimators ranged from 0.43 mm to 2.23 mm for the corresponding model points between the treatment CBCT images and the registered planning images. The mean overlap ratio ranged from 85.5% to 93.2% of the prostate volumes after registration. These results demonstrated reasonably good agreement between the developed method and the gold standards. Conclusion: A novel and fast landmark-based deformable registration method is developed to capture the soft tissue transformation between the planning and treatment images for prostate target volumes. The results show that with the method the image registration and transformation can be completed within one minute and has the potential to be applied to real-time adaptive radiotherapy. 展开更多
关键词 LAPLACIAN surface deformation LAPLACIAN surface Optimization 3D Deformable REGISTRATION PROSTATE
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Hierarchical microstructures with high spatial frequency laser induced periodic surface structures possessing different orientations created by femtosecond laser ablation of silicon in liquids 被引量:17
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作者 Dongshi Zhang Koji Sugioka 《Opto-Electronic Advances》 2019年第3期1-18,共18页
High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or micro... High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles. 展开更多
关键词 HIGH spatial frequency LASER induced periodic surface structures SILICON LASER ablation in liquids HIERARCHICAL MICROSTRUCTURES femtosecond LASER HIGH fluence formation mechanism surface melting nanocapillary wave surface plasmon polaritons second-harmonic generation
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Investigation of Physico-Chemical Characteristics of Stainless Steel Surface and Their Effect on the Appearance Aspects of the Alloy Surface
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作者 Shilpa Vaidya N. C. Debnath 《Journal of Surface Engineered Materials and Advanced Technology》 2019年第4期55-87,共33页
Stainless steel alloy SS-304 is widely used in many engineering applications primarily for its excellent corrosion resistance, ease of fabrication and aesthetic appeal. Many kitchen appliances are made from SS-304 all... Stainless steel alloy SS-304 is widely used in many engineering applications primarily for its excellent corrosion resistance, ease of fabrication and aesthetic appeal. Many kitchen appliances are made from SS-304 alloy because of its durability, ease of cleaning and beautiful finish. However, over the years of continuous usage and cleaning by detergent bar and abrasive clothes the initial brightness and shine of the plates and dishes undergo considerable degradation. In this work, we report the results of a thorough investigation of the physico-chemical characteristics of the surface regions of both new and old SS-304 plates of known history of continuous usage to identify the key physical and chemical factors that are responsible for the loss of shine. Several analytical techniques viz. SEM/EDX, AFM, XPS, XRD, Reflectance FTIR, Profilometry and Reflectance spectrometry in the visible region have been used for experimental investigation of surface structure, morphology, roughness profile, chemical composition and appearance measurements of several steel samples. In addition, glossmeter has been used to measure the gloss of the samples at certain specific angles. It seems that surface roughness is one of the key physical parameters that play an important role in the reduction of brightness and shine. The other parameter is the presence of a thin surface film on the steel surface. In order to analyze the experimental data and to predict the shine and brightness phenomena quantitatively, we have used Fresnel’s theory to compute first the reflectance from each component of SS-304 alloy assuming it to be a smooth surface and then extended it to compute the reflectance of the alloy surface (SS-304). In order to interpret the reflectance from old and used plates, we have further used Beckmann’s theory of light scattering from random rough surface to analyze and predict the appearance aspects of the alloy surface quantitatively. Both the experimental and computed results show good agreement, thus validating the reflectance model used for computing the reflectance from SS-304 alloy surface and the appropriateness of Beckmann’s model of random rough surface. 展开更多
关键词 Loss of SHINE in SS-304 ALLOY surface surface Roughness APPEARANCE Measurements SEM/EDX AFM XPS XRD Reflectance FTIR Profilometry Reflectance Spectroscopy GLOSS Presence of Thin surface Film Beckmanns Model of Random Rough surface
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Numerical simulation of dynamic surface deformation based on DInSAR monitoring 被引量:2
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作者 阎跃观 戴华阳 +3 位作者 葛林林 郭俊廷 AlexHay-ManNG 李晓静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1248-1254,共7页
Differential interferometric synthetic aperture radar (DInSAR) technology is a new method to monitor the dynamic surface subsidence. It can monitor the large scope of dynamic deformation process of surface subsidenc... Differential interferometric synthetic aperture radar (DInSAR) technology is a new method to monitor the dynamic surface subsidence. It can monitor the large scope of dynamic deformation process of surface subsidence basin and better reflect the surface subsidence form in different stages. But under the influence of factors such as noise and other factors, the tilt and horizontal deformation curves regularity calculated by DInSAR data are poorer and the actual deviation is larger. The tilt and horizontal deformations are the important indices for the safety of surface objects protection. Numerical simulation method was used to study the dynamic deformation of LW32 of West Cliff colliery in Australia based on the DInSAR monitoring data. The result indicates that the subsidence curves of two methods fit well and the correlation coefficient is more than 95%. The other deformations calculated by numerical simulation results are close to the theory form. Therefore, considering the influence, the surface and its subsidiary structures and buildings due to mining, the numerical simulation method based on the DInSAR data can reveal the distribution rules of the surface dynamic deformation values and supply the shortcomings of DInSAR technology. The research shows that the method has good applicability and can provide reference for similar situation. 展开更多
关键词 DInSAR monitoring numerical simulation dynamic surface deformation SUPPLEMENT
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The Role of Radiative Surface Modes and Longitudinal Excitons in the Formation of Exciton-Polariton Luminescence Spectra of CdS-Type Crystals
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作者 Bozorboy J. Akhmadaliev Nosirjon Kh. Yuldashev Iftikhorjon I. Yulchiev 《Optics and Photonics Journal》 2018年第3期50-65,共16页
The low-temperature (T = 2 K) exciton-polariton luminescence (EPL) spectra in the vicinity of the exciton-resonance frequency An=1 for CdS-type crystals have been theoretically and experimentally investigated with all... The low-temperature (T = 2 K) exciton-polariton luminescence (EPL) spectra in the vicinity of the exciton-resonance frequency An=1 for CdS-type crystals have been theoretically and experimentally investigated with allowance for the mechanical exciton decay . The results of the numerical calculations of the partial and interference contributions of the bulk and radiative surface spectral modes to the EPL in the geometry of additional s- and p-polarized waves emitted into vacuum are analyzed. It is shown that the contributions of purely longitudinal excitons and their interference with polaritons of the upper dispersion branch near the longitudinal frequency ωL to the EPL are small (&sim;10% - 30%);nevertheless, they must be taken into account to obtain quantitative agreement with experimental data. Specifically these contributions are responsible for the formation of an additional line (along with the fundamental AT line) in the case of oblique incidence of radiation. 展开更多
关键词 EXCITON-POLARITON LUMINESCENCE Spatial Dispersion CdS EXCITON Decay Longitudinal EXCITONS RADIATIVE surface Spectral Modes EXCITON Greens Functions Keldysh Diagram Technique The Partial Contributions and Interference Component of the LUMINESCENCE
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Long-term deformation analysis of Shuibuya concrete face rockfill dam based on response surface method and improved genetic algorithm 被引量:12
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作者 Fu-hai Yao Shao-heng Guan +4 位作者 He Yang Yuan Chen Huan-feng Qiu Gang Ma Qi-wen Liu 《Water Science and Engineering》 EI CAS CSCD 2019年第3期196-204,共9页
Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained fr... Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained from laboratory triaxial tests often underestimate the deformation of high rockfill dams.Therefore, constitutive model parameters obtained by back analysis were used to calculate and predict the long-term deformation of rockfill dams.Instead of using artificial neural networks (ANNs), the response surface method (RSM) was employed to replace the finite element simulation used in the optimization iteration.Only 27 training samples were required for RSM, improving computational efficiency compared with ANN, which required 300 training samples.RSM can be used to describe the relationship between the constitutive model parameters and dam settlements.The inversion results of the Shuibuya concrete face rockfill dam (CFRD) show that the calculated settlements agree with the measured data, indicating the accuracy and efficiency of RSM. 展开更多
关键词 SHUIBUYA ROCKFILL DAM Parameter BACK analysis Response surface method Duncan EB model TIME-DEPENDENT deformation
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Near-field surface deformation during the April 20,2013,Ms7.0 Lushan earthquake measured by 1-Hz GNSS 被引量:3
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作者 Liu Gang Zhao Bin +5 位作者 Zhang Rui Huang Yong Wang Jun Nie Zhaosheng Qiao Xuejun Tan Kai 《Geodesy and Geodynamics》 2013年第2期1-5,共5页
The April 20, 2013, Ms7.0 Lushan earthquake was successfully recorded by closely spaced Continuous Global Positioning System (CGPS) stations owned by the Crustal Movement Observation Network of Chi- na (CMONC). Th... The April 20, 2013, Ms7.0 Lushan earthquake was successfully recorded by closely spaced Continuous Global Positioning System (CGPS) stations owned by the Crustal Movement Observation Network of Chi- na (CMONC). The 1-Hz GNSS data from eight CGPS stations, which are located between 30 km and 200 km from the hypocenter, were processed within quasi-real-time. The near-field surface deformation indicated the following characteristics : the near-field movements were limited to several centimeters ; the peak of the deformation wave was significantly larger than the static permanent offset; at the beginning of the event, the north wall of the fault moved to the southeast as the south wall moved to the southwest ; station SCTQ, which was the closest station to the hypocenter at 30 km, had the largest static permanent displacement of 2 cm; the peaks of the deformation waves were 1.5 cm, 5 cm and 3 cm, to the east, the south and vertically upward, respectively ; and the peaks of velocity and acceleration, derived from the deformation, were 3.4 cm/s and 5.3 cm/s^2,respectively. 展开更多
关键词 Ms7.0 Lushan earthquake CMONC 1-Hz GNSS near-field surface deformation
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Fractal Measures of Drainage Network to Investigate Surface Deformation from Remote Sensing Data: A Paradigm from Hindukush (NE-Afghanistan) 被引量:3
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作者 Syed Amer MAHMOOD Richard GLOAGUEN 《Journal of Mountain Science》 SCIE CSCD 2011年第5期641-654,共14页
This approach represents the relative susceptibility of the topography of the earth to active deformation by means of geometrical distinctiveness of the river networks. This investigation employs the fractal analysis ... This approach represents the relative susceptibility of the topography of the earth to active deformation by means of geometrical distinctiveness of the river networks. This investigation employs the fractal analysis of drainage system extracted from ASTER Global Digital Elevation Model (GDEM-30m resolution). The objective is to mark active structures and to pinpoint the areas robustly influenced by neotectonics. This approach was examined in the Hindukush, NE-Afghanistan. This region is frequently affected by deadly earthquakes and the modern fault activities and deformation are driven by the collision between the northward-moving Indian subcontinent and Eurasia. This attempt is based on the fact that drainage system is strained to linearize due to neotectonic deformation. Hence, the low fractal dimensions of the Kabul, Panjsher, Laghman, Andarab, Alingar and Kocha Rivers are credited to active tectonics. A comprehensive textural examination is conducted to probe the linearization, heterogeneity and connectivity of the drainage patterns. The aspects for these natural textures are computed by using the fractal dimension (FD), lacunarity (LA) and succolarity (SA) approach. All these methods are naturally interrelated, i.e. objects with similar FD can be further differentiated with LA and/or SA analysis. The maps of FD, LA and SA values are generated by using a sliding window of 50 arc seconds by 50 arc seconds (50" × 50"). Afterwards, the maps are interpreted in terms of regional susceptibility to neotectonics. This method is useful to pinpoint numerous zones where the drainage system is highly controlled by Hindukush active structures. In the North-Northeast of the Kabul block, we recognized active tectonic blocks. The region comprising, Kabul, Panjsher, Andrab, Alingar and Badakhshan is more susceptible to damaging events. This investigation concludes that the fractal analysis of the river networks is a bonus tool to localize areas vulnerable to deadly incidents influencing the Earth’s topography and consequently intimidate human lives. 展开更多
关键词 FRACTAL Drainage network LACUNARITY Succolarity surface deformation and Hindukush
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ROLLING DEFORMATION LAW OF ALUMINIUM ALLOY CLAD SHEET
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作者 Zhou, HZ Wang, LY Huang, GJ 《中国有色金属学会会刊:英文版》 CSCD 1999年第2期77-81,共5页
1INTRODUCTIONAlSi/AlMntrilayerbrazedcladaluminiumsheetisthemainmaterialformakingevaporatorandcoolerinth... 1INTRODUCTIONAlSi/AlMntrilayerbrazedcladaluminiumsheetisthemainmaterialformakingevaporatorandcoolerintheairconditionerof... 展开更多
关键词 aluminium alloyclad sheetrolling deformationdeformation lawcan be divided into 3 stages: free (slip or nonrestraining) deformation STAGE PARTIAL restraining (partial clad) deformation STAGE full restraining (full clad) deformation stage.
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Reconstruction of surface deformation characteristics in alpine canyons under shadow conditions 被引量:1
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作者 GU Zhen-kui YAO Xin 《Journal of Mountain Science》 SCIE CSCD 2022年第11期3105-3117,共13页
Monitoring deformation in high undulating mountainous environments is critical for surface process research and disaster prevention studies. Although observations based on interferometric Synthetic Aperture Radar(InSA... Monitoring deformation in high undulating mountainous environments is critical for surface process research and disaster prevention studies. Although observations based on interferometric Synthetic Aperture Radar(InSAR) are an excellent tool for monitoring deformation, the shadow phenomena can limit its application. Based on a series of geomorphic parameters and limited InSAR observation data, surface deformations were reconstructed in areas with missing observations by constructing a random forest model to compensate for the shadow phenomenon at the grid-scale. The findings suggest that this method can be used to rebuild landscape variation characteristics in places where observation data is lacking. The dominant slope direction in the observation area corresponded to a more significant correlation between the reconstructed topography deformation characteristics and the observation. In addition, when building this model, consideration was given to the geomorphic parameter selection, elevation variation, hypsometric integral value, slope form, lithology, slope variation,and aspect variation;these parameters can significantly affect the surface deformation, which is closely related to their spatial autocorrelation. These findings are significant for eliminating the shadow phenomenon, which often occurs in In SAR observations taken over alpine canyon regions. The terrain and lithology of the underlying surface should be considered when reconstructing the surface deformation characteristics of the shadow region by using satellite observation data. 展开更多
关键词 Alpine canyon region surface deformation SHADOW INSAR Geomorphic parameter
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Evaluation of crustal deformation and associated strong motions induced by the 2022 Paktika earthquake,Afghanistan
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作者 A.Bari Jahed Ömer Aydan +1 位作者 Takashi Ito Naoki Iwata 《Earthquake Science》 2024年第6期546-557,共12页
The 2022 Paktika earthquake(moment magnitude:6.2) occurred on June 22,2022,near the border between the Khost and Paktika Provinces of Afghanistan,causing heavy damage and casualties in Paktika Province.This study eval... The 2022 Paktika earthquake(moment magnitude:6.2) occurred on June 22,2022,near the border between the Khost and Paktika Provinces of Afghanistan,causing heavy damage and casualties in Paktika Province.This study evaluated the crustal deformation and associated strong motions induced by the Paktika earthquake.Crustal deformations were determined using the Differential Interferometric Synthetic Aperture Radar(DInSAR) technique and three-dimensional finite element method(3DFEM) and the results were compared.The permanent ground displacements obtained from the DInSAR and 3D-FEM analyses were similar in terms of amplitude and areal distribution.Strong motions were estimated using the 3D-FEM with and without considering regional topography.The estimations of maximum ground acceleration,velocity,and permanent ground deformations were compared among each other as well as with those inferred from failures of some simple structures in the Spera and Gayan districts.The inferred maximum ground acceleration and velocity from the failed adobe structures were more than 300 Gal and 50 cm/s,respectively,nearly consistent with the estimates obtained using empirical methods.The empirical method yielded a maximum ground acceleration of 347 Gal,whereas the maximum ground velocity was approximately50 cm/s.In light of these findings,some surface expressions of crustal deformations and strong ground motions,such as failures of soil and rock slopes and rockfalls,have been presented.The rock slope failures in the epicentral area were consistent with those observed during various earthquakes in Afghanistan and worldwide. 展开更多
关键词 Paktika earthquake FEM SAR AFGHANISTAN fault rupture surface deformation SLOPE ROCKFALL
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Surface seasonal mass changes and vertical crustal deformation in North China from GPS and GRACE measurements 被引量:6
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作者 Shuya Li Wenbin Shen +1 位作者 Yuanjin Pan Tengxu Zhang 《Geodesy and Geodynamics》 2020年第1期46-55,共10页
The Earth is an elastic body,and the surface mass loading changes will lead to elastic loading deformation on the surface of the Earth.In this study,we investigated the surface seasonal mass changes and vertical crust... The Earth is an elastic body,and the surface mass loading changes will lead to elastic loading deformation on the surface of the Earth.In this study,we investigated the surface seasonal mass changes and vertical crustal deformation in North China using the data obtained by the techniques of the Global Positioning System(GPS),Gravity Recovery and Climate Experiment(GRACE)and Surface Loading Models(SLMs).The seasonal annual signal and semi-annual signal obtained by the three techniques show strong correlations.The average value of the weighted root-mean-square(WRMS)of the all 30 sites is 58%after deducting the GRACE-obtained vertical deformation from the GPS-derived vertical deformation.However,the consistency of results between GPS and SLMs is not so good,with a 31%mean WRMS reduction,due to the fact that the global SLMs perform not well in North China.The GRACEmeasured long-term trend is deducted from the GPS-obtained vertical rates to reveal the crustal displacement caused by the underground factors such as tectonic movement and groundwater in North China.The results show that the rates of stations HECX and TJBH are very large,more than 10 mm/yr,which suggests that the surface subsidence is caused by excessive exploitation of groundwater. 展开更多
关键词 Continuous GPS MEASUREMENT GRACE MEASUREMENT surface Loading Models SEASONAL mass changes VERTICAL crustal displacement
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Modeling of co- and post-seismic surface deformation and gravity changes of M W 6.9 Yushu, Qinghai,earthquake 被引量:5
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作者 Chengli Liu Bin Shan +2 位作者 Yong Zheng Ying Jiang Xiong Xiong 《Earthquake Science》 CSCD 2011年第2期177-183,共7页
Based on the elastic dislocation theory, multilayered crustal model, and rupture model obtained by seismic waveform inversion, we calculated the coand post-seismic surface deformation and gravity changes caused by the... Based on the elastic dislocation theory, multilayered crustal model, and rupture model obtained by seismic waveform inversion, we calculated the coand post-seismic surface deformation and gravity changes caused by the Yushu M W 6.9 earthquake occurred on April 14, 2010. The observed GPS velocity field and gravity field in Yushu areas are disturbed by the coand post-seismic effects induced by Yushu earthquake, thus the theoretical coand post-seismic deformation and gravity changes will provide important modification for the background tectonic movement of Yushu and surrounding regions. The time relaxation results show that the influences of Yushu earthquake on Yushu and surrounding areas will last as long as 30 to 50 years. The maximum horizontal displacement, vertical uplift and settlement are about 1.96, 0.27 and 0.16 m, respectively, the maximal positive and negative value of gravity changes are 8.892×10-7 m·s-2 and -4.861×10-7 m·s-2 , respectively. Significant spatial variations can be found on the coand post-seismic effects: The co-seismic effect mainly concentrates in the region near the rupture fault, while viscoelastic relaxation mostly acts on the far field. Therefore, when using the geodetic data to research tectonic motion, we should not only consider the effect of co-seismic caused by earthquake, but also pay attention to the effect of viscoelastic relaxation. 展开更多
关键词 Yushu earthquake viscoelastic relaxation surface deformation GRAVITY
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Rainfall-triggered waste dump instability analysis based on surface 3D deformation in physical model test
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作者 LI Hanlin JIN Xiaoguang +2 位作者 HE Jie XUE Yunchuan YANG Zhongping 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1549-1563,共15页
Landslide is the second largest natural disaster after earthquake. It is of significance to study the evolution laws and failure mechanism of landslides based on its surface 3D deformation information. Based on the ra... Landslide is the second largest natural disaster after earthquake. It is of significance to study the evolution laws and failure mechanism of landslides based on its surface 3D deformation information. Based on the rainfall-triggered waste dump instability model test, we studied the failure mechanisms of the waste dump by integrating surface deformation and internal slope stress and proposed novel parameters for identifying landslide stability. We developed a noncontact measurement device, which can obtain millimeter-level 3D deformation data for surface scene in physical model test;Then we developed the similar materials and established a test model for a waste dump. Based on the failure characteristics of slope surface, internal stress of slope body and displacement contours during the whole process, we divided the slope instability process in model test into four stages: rainfall infiltration and surface erosion, shallow sliding, deep sliding, and overall instability. Based on the obtained surface deformation data, we calculated the volume change during slope instability process and compared it with the point displacement on slope surface. The results showed that the volume change can not only reflect the slow-ultra acceleration process of slope failure, but also fully reflect the above four stages and reduce the fluctuations caused by random factors. Finally, this paper proposed two stability identification parameters: the volume change rate above the slip surface and the relative velocity of volume change rate. According to the calculation of these two parameters in model test, they can be used for study the deformation and failure mechanism of slope stability. 展开更多
关键词 Waste dump stability Physical model test surface 3D deformation Stability identification
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Co-and post-seismic surface deformation and gravity changes of MS 7.0 Lushan,earthquake 被引量:2
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作者 Kai Wang Chengli Liu +1 位作者 Xiong Xiong Yong Zheng 《Earthquake Science》 2013年第3期207-212,共6页
On April 20, 2013, an earthquake with mag- nitude 7.0 occurred in the southwest of the Longmenshan fault system in and around Lushan County, Sichuan Province, China. This devastating earthquake killed hun- dreds of pe... On April 20, 2013, an earthquake with mag- nitude 7.0 occurred in the southwest of the Longmenshan fault system in and around Lushan County, Sichuan Province, China. This devastating earthquake killed hun- dreds of people, injured 10 thousand others, and collapsed countless buildings. In order to analyze the potential risk of this big earthquake, we calculate the co- and post-seismic surface deformation and gravity changes of this event. In this work, a multilayered crustal model is designed, and the elastic dislocation theory is utilized to calculate the co- and post-seismic deformations and gravity changes. During the process, a rupture model obtained by seismic waveform inversion (Liu et al. Sci China Earth Sci 56(7): 1187-1192, 2013) is applied. The time-dependent relaxation results show that the influences on Lushan and its surrounding areas caused by the Ms7.0 Lushan earthquake will last as long as 10 years. The maximum horizontal displacement, vertical uplift, and settlement are about 5 cm, 21.24 cm, and 0.16 m, respectively; the maximal positive and nega- tive values of gravity changes are 45 and -0.47 μGal, respectively. These results may be applied to evaluate the long-term potential risk caused by this earthquake and to provide necessary information for post-earthquake reconstruction. 展开更多
关键词 Lushan earthquake Viscoelasticrelaxation surface deformation GRAVITY
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