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GPR图像的数据集构建及其DRDU-Net去噪算法

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湖南大学学报（自然科学版） 2024年第6期51卷 20-28页

作者：王惠琴高大庆何永强刘宾灿王莹曹明华兰州理工大学计算机与通信学院甘肃兰州730050 西北民族大学土木工程学院甘肃兰州730106 陕西建工安装集团有限公司陕西西安710068

为了解决生成对抗网络(Generative Adversarial Network,GAN)在生成探地雷达(Ground Penetrating Radar,GPR)图像时存在训练不稳定的问题,提出利用带有梯度惩罚的Wasserstein距离生成对抗网络(WGAN-GP)生成GPR图像,并结合时域有限差分... 详细信息

为了解决生成对抗网络(Generative Adversarial Network,GAN)在生成探地雷达(Ground Penetrating Radar,GPR)图像时存在训练不稳定的问题,提出利用带有梯度惩罚的Wasserstein距离生成对抗网络(WGAN-GP)生成GPR图像,并结合时域有限差分法和实地采集图像提出了一种构建GPR图像数据集的方法.相较于原始GAN与Wasserstein GAN等方法,WGAN-GP具有更好的稳定性,而且生成的GPR图像更接近真实图像.在此基础之上,将密集残差块和U-Net相结合提出了一种适合于GPR图像的密集残差去噪U-Net方法.该方法利用U-Net中编码-解码结构提高了GPR图像的去噪性能;同时,密集残差块的引入加强了GPR图像的特征复用,且使U-Net训练更加稳定.最后,利用仿真实验验证了所提去噪方法的性能,并与三维块匹配(BM3D)和U-Net方法进行了对比.结果表明:所提方法与BM3D以及U-Net去噪方法相比,具有更好的去噪效果.当σ等于20时,在模拟和实测数据上取平均值,其峰值信噪比分别提升了约6.5 dB和2.4 dB;结构相似性分别提升了约0.09和0.04.

关键词： GPR数据集构建 GPR图像去噪 WGAN-GP 密集残差块

改进YOLOv5的探地雷达常见地下管线识别

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地球物理学报 2024年第9期67卷 3588-3604页

作者：王惠琴罗佳何永强曹明华高大庆李佳豪兰州理工大学计算机与通信学院兰州730050 西北民族大学土木工程学院兰州730030

针对当前探地雷达(Ground Penetrating Radar,GPR)图像识别准确率低,且小目标识别困难等问题,本文将YOLOv5(You Only Look Once)和ConvNeXt网络相结合,提出一种适用于GPR图像的常见地下管线识别网络ConvNeXt-YOLOv5,显著提高了雷达图像... 详细信息

针对当前探地雷达(Ground Penetrating Radar,GPR)图像识别准确率低,且小目标识别困难等问题,本文将YOLOv5(You Only Look Once)和ConvNeXt网络相结合,提出一种适用于GPR图像的常见地下管线识别网络ConvNeXt-YOLOv5,显著提高了雷达图像中小目标的识别精度.同时,为了解决因地下管线原始信息不足而导致的模型训练精度低的问题,使用实测GPR图像、时域有限差分法(Finite-Difference Time-Domain,FDTD)与混类增强算法Mixup模拟图像构建数据集.然后,在此数据集上验证了本文所提方法对常见地下管线的识别效果,并用识别后的二维GPR B-scan图像还原出地下管线的三维图像.实验结果表明,对镀锌输水钢管、PVC管、电缆线和含水塑料瓶等常见地下管线进行识别时,ConvNeXt-YOLOv5表现出优良的识别性能.尤其是对PVC管的识别精度提升明显.与YOLOv4、YOLOv5、YOLOv7和Faster R-CNN模型相比,其平均精度均值分别提高了3.83%、2.82%、1.9%和3.72%.同时,三维探地雷达图像更直观的还原了地下管线信息.

关键词：探地雷达地下管线深度学习 ConvNeXt 三维显示

INVESTIGATION ON THE FLOW STABILITY OF NEWTONIAN FLUID IN ECCENTRIC ANNULUS VIA THE AXIAL RECIPROCATION OF THE INNER TUBE

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Journal of Hydrodynamics 2007年第6期19卷 671-676页

作者： YUAN Ai-wu CUI Hai-qing gao Tao Management Institute Tianjin University Tianjin 300072 China Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China daqing Exploration and Development Institute Daqing 163712 China

The governing equation, together with the formulas of the averaged flux and the stability parameter for Newtonian fluid flowing in eccentric annulus via the axial reciprocation of the inner tube was established in the bipolar coordinate system. Numerical calculation was conducted for the measurement of water flow using the formulas above, of which the results agree well with the experimental data. It is shown that the flow instability can be induced by the increase of the stroke, the frequency, and the eccentricity of annulus, making the sucker rod more susceptible to partial abrasion. Some protecting methods, including adding centralizers, adjusting the stroke and frequency, are proposed to protect the sucker rod from the partial abrasion, and satisfactory results have been achieved in the oilfields.

关键词： eccentric annulus axial reciprocation flow stability partial abrasion

R&D Progress of HIAF Kicker Power Supply

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IMP & HIRFL Annual Report 2022年第1期 231-232页

作者： gao Jie gao daqing 不详

Kicker power supply is one of the key components of the high-intensity heavy ion accelerator *** is also one of the main components to achieve fast extraction of the beam from BRing and fast injection of the beam to *** 1 shows the technical indicators of the BRing Kicker power supply and SRing Kicker power *** adopts the scheme of Blumlein-PFN and thyratron solution.

关键词： HIAF beam injection

Progress of Power Supply System In 2017

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IMP & HIRFL Annual Report 2017年第1期 261-263页

作者： gao daqing Zhou Zhongzu 不详

More than 100 power supplies are upgraded in the last two years based on full-digital power supply *** operation performance is getting better and *** 2017,HIRFL power supply system operated more than 7000 *** work of PS group focuses on *** nuclei mass measurement experiment at CSRe is the most important research in IMP in recent *** the dipole magnet power supply of the CSRe is not stable,which impacted the operation stability of *** new power supplies are designed and put into operation by the end of the *** first test results show the current stability and the ripple are improved *** the same time,a complex upgrade is done for good EMI performance at CSRe.

关键词： power stability performance

Progress of Power Supply Systems in 2018

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IMP & HIRFL Annual Report 2018年第1期 252-253页

作者： gao daqing Zhou Zhongzu 不详

Through continuous research and development,improving the stability and reliability of HIRFL(Heavy Ion Research Facility in Lanzhou)power supply equipment is an important work for the power supply *** 2018,cable tray reconstruction work has been done in RIBLL2(Radioactive Ion Beam Line in Lanzhou)to improve the electromagnetic compatibility environment of CSR(Cooling Storage Ring)equipment *** on the requirement of power supply system in HIAF(High Intensity Heavy-ion Accelerator Facility)project,the prototype of fast circulating fast ramping power supply has been developed,and fundamental progress has been *** the research and development of new power supply technology,a high density power module was developed to further reduce the power supply *** construction of power distribution monitoring center and upgrade of 10 kV high voltage integrated automatic protection system have been completed.

关键词： power system Power

6-18 Operation and Improvement of HIRFL Power Supply System

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IMP & HIRFL Annual Report 2015年第1期 285-286页

作者： gao daqing Zhou Zhongzu 不详

In order to continually meet the requirements of accelerator, power supply technique at IMP has developed from DC output to pulse output, from slow pulse output to fast pulse output, from analogue control to digital control. Through development and technology accumulation for about forty years, IMP has formed its own characteristics in many types of power supply, such as high stability DC power supply, PULSE power supply, injection and extraction power supply, etc. In 2015, the work was mainly focused on improving the performance of CSRe (cooling storage experimental ring) and RIBLL 2 (Radioactive Ion Beam Line in Lanzhou) power supplies.

关键词： Power Supply System

6 - 16 Progress of Power Supply System in 2013

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IMP & HIRFL Annual Report 2013年第1期 244-245页

作者： gao daqing Zhou Zhongzu

6-21 Progress of Power Supply System In 2016

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IMP & HIRFL Annual Report 2016年第1期 272-273页

作者： gao daqing Zhou Zhongzu 不详

In 2016,the power supply in CSRm was digitalized to further improve the reliability of operation.A new vector rectication technique is developed for the research of advanced power supply and electrical related technologies.A number of EMC and electrical safety testing items for HIMM Wuwei power supplies has been *** upgrade of the power supply CSRm power supply,including 30 sets quadrupole magnet power supply,6 sets sextupole magnet power supply and 8 sets bipolar correct magnet power supply,were transformed by using of digital controllers based on ***.1 displays the measurement results of the new digital power supply of quadrupole magnet,the current error(at top)was 1.7610?5,the tracking er-ror was 5.2810?*** performance and reliability of the power supply have been greatly improved.

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