Ndt & E International最新文献_第2页

Wall thinning quantification with a lift-off distance for ferromagnetic structures using pulsed ECT equipped with ICA-Gauss filter and Hough Transform 利用配备 ICA-Gauss 滤波器和 Hough 变换的脉冲 ECT，对铁磁性结构的壁薄进行升程量化

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-12 DOI: 10.1016/j.ndteint.2024.103272

Jizhou Zhang , Siwei Fan , Guohang Lu , Shuyan Yang , Shejuan Xie , Zhenmao Chen , Yang Zheng , Tetsuya Uchimoto , Toshiyuki Takagi

{"title":"Wall thinning quantification with a lift-off distance for ferromagnetic structures using pulsed ECT equipped with ICA-Gauss filter and Hough Transform","authors":"Jizhou Zhang , Siwei Fan , Guohang Lu , Shuyan Yang , Shejuan Xie , Zhenmao Chen , Yang Zheng , Tetsuya Uchimoto , Toshiyuki Takagi","doi":"10.1016/j.ndteint.2024.103272","DOIUrl":"10.1016/j.ndteint.2024.103272","url":null,"abstract":"<div><div>Determining the thickness of ferromagnetic materials with a lift-off distance poses a significant challenge for current non-destructive testing (NDT) techniques. Pulsed eddy current (PEC) testing is deemed as a powerful candidate to evaluate this type of defect. However, the signal-to-noise ratio (SNR) of the PEC response signal obtained with large lift-off distance is very poor, so that the signal feature can hardly be extracted. To improve the SNR of PEC response signals and capture the signal feature adaptively, this paper proposed a novel PEC signal processing algorithm based on ICA-Gauss filter and Hough Transform (HT). Firstly, the principle of the proposed method was introduced. Then, two case studies, a comparison experiment and an application experiment were conducted to verify the effectiveness and accuracy of this method. Results from these experiments show that (a) the ICA-Gauss filter can effectively suppress the power-line noises and random noises in PEC signals, (b) the ICA-Gauss filter outperforms traditional filters in feature robustness and computing efficiency, including double-logarithmic median filter and Savitzky-Golay filter, and (c) HT is an adaptive and accurate method to extract the PEC signal feature, thus achieving a small detection error.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103272"},"PeriodicalIF":4.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimising full waveform inversion with inhomogeneous transducers: Parameters and considerations for successful implementation 利用非均质传感器优化全波形反演：成功实施的参数和注意事项

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-07 DOI: 10.1016/j.ndteint.2024.103265

Carlos-Omar Rasgado-Moreno , Panpan Xu , Marek Rist , Madis Ratassepp

{"title":"Optimising full waveform inversion with inhomogeneous transducers: Parameters and considerations for successful implementation","authors":"Carlos-Omar Rasgado-Moreno , Panpan Xu , Marek Rist , Madis Ratassepp","doi":"10.1016/j.ndteint.2024.103265","DOIUrl":"10.1016/j.ndteint.2024.103265","url":null,"abstract":"<div><div>Guided wave tomography (GWT) based full waveform inversion (FWI) is an emerging technique for structural health monitoring applications, primarily for plates and pipeline structures. Generally, FWI employs a two-dimensional (2-D) forward model to circumvent the high computational cost associated with the inversion scheme. Consequently, a re-scaling step is implemented to compensate for any potential discrepancies between the 2-D model and the observed data. Druet et al., (2019) introduced the autocalibration method, which utilises the information from the healthy rays to calibrate those rays that pass through the defect. In this method, only the phase information is re-scaled, given that phase information is the dominant factor in FWI. However, overlooking amplitude discrepancies might lead the inversion scheme to become trapped in a local minimum. In this study, we propose to include the amplitude information as well, following the autocalibration method. We use an updated autocalibration method to reconstruct a 100 mm wide defect on an 8 mm thick steel straight pipe with traditional GWT using the <span><math><msub><mrow><mi>A</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> mode. This novel approach provides a more accurate representation of the defect and avoids becoming trapped in a local minimum, thereby improving the reliability and effectiveness of FWI. Furthermore, we offer guidance for the successful implementation of this method in the presence of inhomogeneous transducers, a common challenge in practical applications.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103265"},"PeriodicalIF":4.1,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A simplified procedure for evaluation of damage-depth in concrete exposed to high temperature using the impact-echo method 利用冲击回波法评估暴露于高温下的混凝土的破坏深度的简化程序

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-07 DOI: 10.1016/j.ndteint.2024.103270

Hsuan-Chih Yang , Yiching Lin

{"title":"A simplified procedure for evaluation of damage-depth in concrete exposed to high temperature using the impact-echo method","authors":"Hsuan-Chih Yang , Yiching Lin","doi":"10.1016/j.ndteint.2024.103270","DOIUrl":"10.1016/j.ndteint.2024.103270","url":null,"abstract":"<div><div>Concrete is widely recognized as a material capable of withstanding the intrusion of high temperatures during fires. However, under different high-temperature conditions, concrete can still experience strength reduction, cracking, or spalling, which can significantly impact the safety and durability of concrete structures. Conventionally, the wave refraction technique was used to detect the depth of this damage layer. However, the wave refraction technique is a time-consuming point-by-point detection method. In order to increase detection efficiency, this paper proposes a simplified method based on a single-point test. Numerical analysis of the thermal conduction of a concrete slab exposed to elevated temperature was performed first to investigate the temperature distribution within the concrete slab. Subsequently, the wave refraction technique was numerically simulated to evaluate the damage depth of the concrete slab. According to the refracted wave propagation path, a simplified procedure is proposed for the detection of the damage depth of concrete under high temperature. In the simplified procedure, a receiver is placed at an adequate distance from the impact source so that the first arrival wave at the receiver will be a wave refracted from the interface between the damaged layer and the sound layer inside the concrete. To verify the applicability of the proposed simplified procedure, concrete slab specimens subjected to an elevated temperature of 600 °C were tested in this study. The experimental results indicate that the simplified method proposed in this paper can indeed be used to detect the depth of high-temperature damage in concrete. In addition, the experimental results show that under the same high-temperature exposure conditions, the depth of fire damage increases with a decrease in the water-cement ratio. This can be attributed to the higher thermal conductivity coefficient of concrete with a lower water-cement ratio.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103270"},"PeriodicalIF":4.1,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Characterization of heat-treated bearing rings via measurement of electromagnetic properties for pulsed eddy current evaluation 通过测量脉冲涡流评估的电磁特性表征热处理轴承套圈

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-07 DOI: 10.1016/j.ndteint.2024.103268

Jingwei Sha , Hong Zhang , Mengbao Fan , Binghua Cao , Fengshan Sun

{"title":"Characterization of heat-treated bearing rings via measurement of electromagnetic properties for pulsed eddy current evaluation","authors":"Jingwei Sha , Hong Zhang , Mengbao Fan , Binghua Cao , Fengshan Sun","doi":"10.1016/j.ndteint.2024.103268","DOIUrl":"10.1016/j.ndteint.2024.103268","url":null,"abstract":"<div><div>Nondestructive evaluation of heat-treated bearing rings is a critical technique for quality control in industries. However, there are few reports addressing the complex mapping between hardness and electromagnetic properties due to the intricate changes in the microstructure. This paper proposes a dual-method approach, combining magnetic saturation eddy current techniques and Barkhausen noise reconstruction hysteresis loop techniques, to independently establish the relationship between hardness and electromagnetic properties. The results show that the electrical properties of unqualified specimens are significantly higher than those of other specimens, with qualified specimens have slightly higher properties than untreated ones. Additionally, an inverse relationship between hardness and magnetic properties is observed. Based on the obtained electromagnetic parameters, a pulsed eddy current hardness detection simulation model is established, which has the potential to improve purely data-driven methods for hardness detection in deep learning.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103268"},"PeriodicalIF":4.1,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel damage localization method of Circular Phased Array using Minimum Variance Distortionless Response Beamforming with Autocorrelation Matrix Diagonal Loading 利用自相关矩阵对角线加载的最小方差无失真响应波束成形的新型圆形相控阵损伤定位方法

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-05 DOI: 10.1016/j.ndteint.2024.103267

Yonghui An , Shilong Ni , Ranting Cui , Jinping Ou

{"title":"A novel damage localization method of Circular Phased Array using Minimum Variance Distortionless Response Beamforming with Autocorrelation Matrix Diagonal Loading","authors":"Yonghui An , Shilong Ni , Ranting Cui , Jinping Ou","doi":"10.1016/j.ndteint.2024.103267","DOIUrl":"10.1016/j.ndteint.2024.103267","url":null,"abstract":"<div><div>Damage localization methods based on Acoustic Emission (AE) can be classified into time-based and waveform-based. However, the former requires a large number of sensors while the latter is limited to 2D plane localization. In order to address the challenge of achieving more accurate 3D localization using a reduced number of sensors, this paper proposes a Circular Phased Array using Minimum Variance Distortionless Response (MVDR) Beamforming with Autocorrelation Matrix Diagonal Loading (AMDL) method. Firstly, a sparse circular array is utilized to form multiple beamforming for coherent shear wave signals, decomposing the original 3D localization problem into Direction Of Arrival (DOA) estimation. Secondly, azimuth angle, elevation angle and autocorrelation matrix diagonal loading methods are introduced, working in conjunction with the MVDR beamforming algorithm. Finally, spatial integration is performed through matrix decomposition to solve geometric overdetermined equations. The effectiveness of the proposed method is validated through numerical simulations and experimental verifications under various damage conditions. Results indicate that estimation errors for azimuth and elevation angles are both less than 2 %, while 3D damage source localization errors remain within a range of less than 3 %. This proposed method extends beamforming technology from 2D plane localization to 3D localization, significantly reducing the complexity of sensor arrangement and lowering the cost of structural health monitoring systems by utilizing a small number of sensors.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103267"},"PeriodicalIF":4.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Novel fast full-wavefield modeling of air-coupled surface waves and its implications for non-contact pavement testing 空气耦合表面波的新型快速全波场建模及其对非接触式路面测试的影响

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-05 DOI: 10.1016/j.ndteint.2024.103266

Quoc Kinh Tran , Chih-Ping Lin , Ernian Pan , Tsai-Jung Wu , Yin-Ming Po

{"title":"Novel fast full-wavefield modeling of air-coupled surface waves and its implications for non-contact pavement testing","authors":"Quoc Kinh Tran , Chih-Ping Lin , Ernian Pan , Tsai-Jung Wu , Yin-Ming Po","doi":"10.1016/j.ndteint.2024.103266","DOIUrl":"10.1016/j.ndteint.2024.103266","url":null,"abstract":"<div><div>We present a novel approach for deriving and modeling air-coupled surface waves with applications in non-contact non-destructive testing (NDT). It is based on the fast Fourier-Bessel series system in conjunction with the unconditionally stable dual-variable and position matrix method. Parametric studies, including sensitivity analysis, are conducted to assess the feasibility of using non-contact air-coupled measurements for pavement testing, focusing on Green's functions, time-domain waveforms, and experimental frequency-velocity spectra (FVS, i.e., the estimated Green's functions from acquired truncated wavefield). The predicted experimental FVS presented in this study are synthetic dispersion images, which are distinguished from the measured experimental FVS (i.e., measured dispersion images from multichannel analysis of surface wave (MASW) test). With the derived complete solution of air-coupled dynamic responses, we find that: <strong>(1)</strong> Striking similarities between the theoretical Green's functions of vertical displacement (on the pavement surface) and pressure (in the air), as well as in their corresponding experimental FVS. <strong>(2)</strong> The proposed accurate and efficient full-wave modeling of air-coupled surface waves avoids the need for good contact between geophones/accelerometers and pavement surface. This facilitates direct inversion of shear wave velocity profiles by fitting the predicted experimental FVS to the measured one. <strong>(3)</strong> Sensitivity analysis demonstrates no significant loss of information in the pressure measured in the air, supporting the feasibility of using non-contact measurement for non-destructive testing. These results suggest that non-contact air-coupled measurements hold great promise as a viable alternative to contact measurements in non-destructive testing.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103266"},"PeriodicalIF":4.1,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Image enhancement methods for inspection of planar and non-planar FRP structures using a noise-based microwave NDT inspection system 使用基于噪声的微波无损检测系统检测平面和非平面玻璃钢结构的图像增强方法

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-11-04 DOI: 10.1016/j.ndteint.2024.103264

Marc D. Navagato, Ram M. Narayanan

{"title":"Image enhancement methods for inspection of planar and non-planar FRP structures using a noise-based microwave NDT inspection system","authors":"Marc D. Navagato, Ram M. Narayanan","doi":"10.1016/j.ndteint.2024.103264","DOIUrl":"10.1016/j.ndteint.2024.103264","url":null,"abstract":"<div><div>Microwave nondestructive testing (MNDT) includes inspection techniques that assess a particular material’s health status using low-power and contactless inspection systems. In near-field microwave inspections, imaging results are heavily influenced by the standoff distance parameter, i.e., the physical separation between the microwave sensor and the sample under test (SUT). Variations in the standoff distance during an inspection tend to cause defect masking of disbonds and delaminations in fiber-reinforced polymer (FRP) materials, causing defects to go undetected frequently. An MNDT near-field inspection system using noise waveforms is used to identify engineered internal defects within carbon fiber-reinforced polymer (CFRP) samples. Tactics utilizing Principal Component Analysis (PCA), Stacked Sparse Autoencoders (SSAEs), and an autoencoder network trained in a manner for anomaly detection are used to minimize the effects of standoff distance, reduce defect masking, and increase the ability to identify hidden defects. The samples tested are constructed to possess planar and non-planar geometries, such that the viability of the data-driven image enhancement and standoff distance correction methods are demonstrated with respect to a wide variety of in situ inspection applications.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103264"},"PeriodicalIF":4.1,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142662192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Translation of MFL and UT data by using generative adversarial networks: A comparative study 使用生成式对抗网络翻译 MFL 和 UT 数据：比较研究

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-10-23 DOI: 10.1016/j.ndteint.2024.103246

Jiatong Ling , Xiang Peng , Matthias Peussner , Kevin Siggers , Zheng Liu

{"title":"Translation of MFL and UT data by using generative adversarial networks: A comparative study","authors":"Jiatong Ling , Xiang Peng , Matthias Peussner , Kevin Siggers , Zheng Liu","doi":"10.1016/j.ndteint.2024.103246","DOIUrl":"10.1016/j.ndteint.2024.103246","url":null,"abstract":"<div><div>Magnetic flux leakage (MFL) and ultrasonic testing (UT) are widely used in-line inspection technologies to detect corrosion defects along pipelines. The integration of MFL and UT data has the potential to provide complementary insights that facilitate a comprehensive assessment of pipeline integrity. However, due to the inherent dissimilarity with their underlying physical principles, these techniques yield notable disparities in signal characteristics, posing challenges in integrating these multimodal data. This study aims to establish a translation mapping between MFL and UT signals to achieve consistent physical interpretations across the two modalities. Thus, this study explored the feasibility of generative adversarial network (GAN) based models encompassing both supervised and unsupervised translation approaches contingent on the availability of aligned data. Furthermore, two translation modes, MFL-UT and UT-MFL, were analyzed separately to understand the effectiveness of the translation direction. The experimental results demonstrate satisfactory performance for both aligned and unaligned data translation, with the UT-MFL translation direction yielding superior results. Overall, the translation approaches pave the way for future applications, especially in subsequent data analysis tasks such as registration, comparison, and fusion of multimodal data.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103246"},"PeriodicalIF":4.1,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a flexible phased array electromagnetic acoustic testing system with array pickups 开发带阵列拾波器的柔性相控阵电磁声学测试系统

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-10-21 DOI: 10.1016/j.ndteint.2024.103263

Jie Deng, Yuange Zhang, Yinqiang Qu, Cuixiang Pei, Tianhao Liu, Zhenmao Chen

{"title":"Development of a flexible phased array electromagnetic acoustic testing system with array pickups","authors":"Jie Deng, Yuange Zhang, Yinqiang Qu, Cuixiang Pei, Tianhao Liu, Zhenmao Chen","doi":"10.1016/j.ndteint.2024.103263","DOIUrl":"10.1016/j.ndteint.2024.103263","url":null,"abstract":"<div><div>The thermal barrier coatings (TBCs) used to protect blades of heavy-duty gas turbines is prone to debonding defects during fabrication and service. It is difficult to detect the debonding defects in the TBC system non-destructively and in situ due to the curved shape of blade and the narrow space between the blades setting in the gas turbine. In this paper, a flexible phased array electromagnetic acoustic (FPA-EMA) testing system with array pickups is developed, which is capable to drive a flexible phased array electromagnetic acoustic transducer (FPA-EMAT) to generate and receive ultrasonic wave directly in the metallic substrate of TBCs, and is potential to be applied to the inspection of debonding defects in the TBC system of gas turbine blades. A phased array excitation unit, a multi-channel signal receiving unit and a new signal post-processing algorithm are developed for the new EMA testing system to enhance the surface acoustic wave in the layered structure and to improve the low conversion efficiency of the conventional EMA testing system. In addition, a bias magnetic field coil fed with long pulse current of large amplitude is adopted to make the new EMAT thin and flexible in order to be applied in a narrow space. The interfering noise and geometric size problems brought by the multiple excitation and pickup channels are well addressed in the new system. The good performances of the developed FPA-EMA testing system were verified experimentally and show the system of good potential to be applied to NDT of practical curved structures.</div></div>","PeriodicalId":18868,"journal":{"name":"Ndt & E International","volume":"149 ","pages":"Article 103263"},"PeriodicalIF":4.1,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142531807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Mobius transformation-based liftoff effect reduction method for crack classification and prediction in eddy current testing 基于莫比乌斯变换的升力效应减弱法，用于涡流测试中的裂纹分类和预测

IF 4.1 2区材料科学

Ndt & E International Pub Date : 2024-10-21 DOI: 10.1016/j.ndteint.2024.103261

Yu Li , Zihan Xia , Saibo She , Yuchun Shao , Yinchao Yang , Wuliang Yin

引用次数: 0