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Revealing the interaction mechanism of pulsed laser processing with the application of acoustic emission

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Frontiers of Optoelectronics 2023年第2期16卷 91-101页

作者： weinan liu Youmin Rong Ranwu Yang Congyi Wu Guojun Zhang Yu Huang State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

The mechanisms of interaction between pulsed laser and materials are complex and indistinct,severely infuencing the stability and quality of laser processing.This paper proposes an intelligent method based on the acoustic emission(AE)technique to monitor laser processing and explore the interaction mechanisms.The validation experiment is designed to perform nanosecond laser dotting on foat glass.Processing parameters are set diferently to generate various outcomes:ablated pits and irregular-shaped cracks.In the signal processing stage,we divide the AE signals into two bands,main and tail bands,according to the laser processing duration,to study the laser ablation and crack behavior,respectively.Characteristic parameters extracted by a method that combines framework and frame energy calculation of AE signals can efectively reveal the mechanisms of pulsed laser processing.The main band features evaluate the degree of laser ablation from the time and intensity scales,and the tail band characteristics demonstrate that the cracks occur after laser dotting.In addition,from the analysis of the parameters of the tail band very large cracks can be efciently distinguished.The intelligent AE monitoring method was successfully applied in exploring the interaction mechanism of nanosecond laser dotting foat glass and can be used in other pulsed laser processing felds.

关键词： Laser dotting Acoustic emission Monitoring Laser ablation Cracks

Total organic carbon content logging prediction based on machine learning:A brief review

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能源地球科学(英文)

能源地球科学(英文) 2023年第2期4卷 100-107页

作者： Linqi Zhu Xueqing Zhou weinan liu Zheng Kong Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanyaHainan572000China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai ZhuhaiGuangdong519000China CNOOC China Limited LtdShenzhen BranchShenzhen518054China Exploration and Development Research Institute Shengli Oilfield CompanySINOPECDongyingShandong257029China

The total organic carbon content usually determines the hydrocarbon generation potential of a formation.A higher total organic carbon content often corresponds to a greater possibility of generating large amounts of oil or gas.Hence,accurately calculating the total organic carbon content in a formation is very important.Present research is focused on precisely calculating the total organic carbon content based on machine learning.At present,many machine learning methods,including backpropagation neural networks,support vector regression,random forests,extreme learning machines,and deep learning,are employed to evaluate the total organic carbon content.However,the principles and perspectives of various machine learning algorithms are quite different.This paper reviews the application of various machine learning algorithms to deal with total organic carbon content evaluation problems.Of various machine learning algorithms used for TOC content predication,two algorithms,the backpropagation neural network and support vector regression are the most commonly used,and the backpropagation neural network is sometimes combined with many other algorithms to achieve better results.Additionally,combining multiple algorithms or using deep learning to increase the number of network layers can further improve the total organic carbon content prediction.The prediction by backpropagation neural network may be better than that by support vector regression;nevertheless,using any type of machine learning algorithm improves the total organic carbon content prediction in a given research block.According to some published literature,the determination coefficient(R^(2))can be increased by up to 0.46 after using machine learning.Deep learning algorithms may be the next breakthrough direction that can significantly improve the prediction of the total organic carbon content.Evaluating the total organic carbon content based on machine learning is of great significance.

关键词： Total organic carbon content Well logging Machine learning Backpropagation neural network Support vector regression

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亚临界雷诺数下串列双波浪锥柱绕流数值模拟

北京航空航天大学学报 2024年第3期50卷 706-715页

作者：邹琳吴伟男刘健柳迪伟王家辉武汉理工大学机电工程学院武汉430000

针对风力俘能结构布局问题,基于大涡模拟(LES)方法,在亚临界雷诺数下(Re=3900)研究有限长串列双波浪锥柱的升阻力特性及其流动结构随间距比的变化规律。结果表明:由于上游波浪锥柱的影响,下游波浪锥柱的脉动升力系数大幅增大,当间距比为... 详细信息

针对风力俘能结构布局问题,基于大涡模拟(LES)方法,在亚临界雷诺数下(Re=3900)研究有限长串列双波浪锥柱的升阻力特性及其流动结构随间距比的变化规律。结果表明:由于上游波浪锥柱的影响,下游波浪锥柱的脉动升力系数大幅增大,当间距比为3时,表面时均压力系数分布形式呈反向分布;随间距比增加,上游波浪锥柱尾流充分发展,并产生大量肋状涡撞击在下游波浪锥柱表面,下游波浪锥柱产生大的脉动升力,相较于单直圆柱提升约15.3倍,阻力系数降低约0.172。所得结果可为风力俘能结构布局提供有益参考。

关键词：串列双波浪锥柱间距比升阻力特性流动结构大涡模拟

Tanshinone IIa antagonizes spinal ischemia/reperfusion injury by interfering with upstream glutamic acid factors

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Neural Regeneration Research 2010年第20期5卷 1573-1577页

作者： Li Zhang Xiang Lin weinan liu Jianhua Lin School of Traumatology and Orthopedics Fujian University of Traditional Chinese Medicine Fuzhou 350108 Fujian Province China Department of Traumatology and Orthopedics People's Hospital of Fujian University of Traditional Chinese Medicine Fuzhou 350004 Fujian Province China Department of Orthopedics First Affiliated Hospital of Fujian Medical University Fuzhou 350005 Fujian Province China

Based on the hypothesis that upstream factor inhibition results in better treatment effects than downstream factor inhibition,the present study interfered with glutamic acid（Glu）-released upstream factors,such as Glu transporter function and Na＋-K＋-adenosine triphosphatases（ATPase）activity relativly.Rats with spinal cord ischemia/reperfusion injury received intraperitoneal injections of tanshinone Ila and Glu uptake and Na＋-K＋-ATPase activity were increased.Results showed that tanshinone Ila influenced Glu-released upstream factors following spinal ischemia/reperfusion injury and protected against spinal ischemia/reperfusion injury.

关键词： spinal cord ischemia/reperfusion injury tanshinone glutamic acid transporter Na＋-K＋-ATPase neural regeneration

基于乐观行动-评判深度强化学习的含氢综合能源系统低碳经济调度

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电网技术 2024年第5期48卷 1873-1883,I0016,I0018-I0020页

作者：孙惠娟段伟男陈俐刘金祥彭春华华东交通大学电气与自动化工程学院江西省南昌市330013

“双碳”背景下,以氢能为能源载体的含氢综合能源系统是中国能源行业低碳化转型的重要支撑。为保证含氢综合能源系统中的氢能供给并提高用氢效率,该文提出了一种电气混合制氢及氢能综合利用的综合能源系统运行模式;并基于碳捕集装置和... 详细信息

“双碳”背景下,以氢能为能源载体的含氢综合能源系统是中国能源行业低碳化转型的重要支撑。为保证含氢综合能源系统中的氢能供给并提高用氢效率,该文提出了一种电气混合制氢及氢能综合利用的综合能源系统运行模式;并基于碳捕集装置和综合需求响应建立了源荷互补降碳机制,以充分挖掘系统降碳潜能,进一步提升可再生能源消纳率及系统低碳化水平;此外,为了对含氢综合能源系统中的源荷随机波动实现快速响应,提出基于乐观行动-评判深度强化学习方法对系统优化调度模型进行离线训练和在线优化求解,可高效实现含氢综合能源系统的低碳经济在线优化调度。最后通过算例应用验证了所提方法的优越性。

关键词：含氢综合能源系统互补降碳低碳经济调度深度强化学习氢能综合利用

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利用光学影像的滑坡位移监测

测绘通报 2024年第6期 41-45,64页

作者：刘卫南宋红克李清波谢谟文黄河勘测规划设计研究院有限公司河南郑州450003 水利部黄河流域水治理与水安全重点实验室(筹) 河南郑州450003 北京科技大学土木与资源工程学院北京100083

为充分挖掘光学遥感图像在滑坡监测中的应用潜力,本文基于数字图像相关法推导了适应滑坡非均匀形变和自然光照影响的滑坡位移光学影像计算公式,形成了基于光学影像的滑坡位移监测方法。试验分析了地表形变方式和形变量对滑坡位移光学影... 详细信息

为充分挖掘光学遥感图像在滑坡监测中的应用潜力,本文基于数字图像相关法推导了适应滑坡非均匀形变和自然光照影响的滑坡位移光学影像计算公式,形成了基于光学影像的滑坡位移监测方法。试验分析了地表形变方式和形变量对滑坡位移光学影像计算公式的影响,给出了地表平移、旋转、扭曲3种不同形变方式下,计算误差的概率累计值变化曲线,证明了该公式95%计算结果的相对误差在0.04以内;利用两期SkySat卫星光学影像计算了某滑坡的平面位移场,分析了该滑坡的表面形变特征。本文研究为滑坡灾害监测预警提供了新的技术参考。

关键词：滑坡监测数字图像相关光学影像遥感

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金属磁记忆检测的关键技术研究现状与展望

压力容器 2024年第1期41卷 70-82页

作者：邢海燕段成凯刘长皓徐成刘伟男刘传东北石油大学机械科学与工程学院黑龙江大庆163318

金属磁记忆检测技术是一种绿色无污染、可检出早期应力集中、隐性损伤以及宏观缺陷的全寿命无损检测技术,经过20多年发展,已取得众多研究成果并应用于压力容器、石油管道、铁路桥梁、能源电力、航空航天等重要领域。针对金属磁记忆检测... 详细信息

金属磁记忆检测技术是一种绿色无污染、可检出早期应力集中、隐性损伤以及宏观缺陷的全寿命无损检测技术,经过20多年发展,已取得众多研究成果并应用于压力容器、石油管道、铁路桥梁、能源电力、航空航天等重要领域。针对金属磁记忆检测技术近年来的热点与难点问题,从理论基础到工程应用中的关键技术出发,归纳总结了磁记忆检测技术的机理、信号降噪与特征提取,以及机器学习在磁记忆检测评价中的应用等方面的研究现状,并对磁记忆检测技术亟待解决的关键难点问题与未来发展方向进行了探讨。

关键词：磁记忆机理信号降噪特征提取定量评价机器学习

Clinical Application of X-ray,B-scan,and CT in the Diagnosis of Ocular Foreign Bodies

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Eye Science 2013年第1期28卷 11-14页

作者： Shihuai Nie Zhonghao Wang weinan liu Xuanwei Liang State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Department of Radiology Qifu Hospital Guangzhou University of Chinese Medicine

Purpose:To analyze the sensitivity and specificity of X-ray, B-ultrasound, and CT scan in diagnosing ocular foreign bodies, and to compare the accuracy of these three imaging tools in locating these foreign bodies. Methods:A retrospective review was conducted of radio graphic and clinical eye examination data from 62 patients (66 eyes),suspected of having ocular foreign bodies at time of first presentation to the Zhongshan Ophthalmic Center (Guangzhou, China) between August 2007 and October 2011. The sensitivity and specificity of X-ray, B-ultrasound and CT scan in the diagnosis of ocular foreign bodies were investigated and their accuracy in locating these foreign bodies was compared. Results: A total of 75.8% (n=47) subjects had ocular foreign bodies; 66% of these were metallic. Patients with intraocular, eye wall,and extraocular foreign bodies accounted for 46, 28, and 26% of the total, respectively. The sensitivities of X-ray,CT scan,and B-ultrasound in the diagnosis of ocular foreign bodies were 58.3%, 61.7%, and 75%, the specificityies were 63.3%, 100%, and 87.5%, and the accuracy in locating foreign bodies was 73.4%, 94.7%, and 86.5%, respectively. The properties of foreign bodies affected the diagnosistic accuracy of X-ray,but exerted little impact upon B-ultrasound and CT scan. Conclusion:A fairly high incidence of ocular foreign bodies was noted in patients suspected with ocular foreign bodies at their first presentations.X-ray combined with CT scan or X-ray in combination with B-ultrasound showed a relatively high sensitivity and specificity in diagnosing ocular foreign bodies. CT scan had the highest accuracy in locating ocular foreignbodies. (Eye Science 2013; 28:11-14)

关键词： CT扫描 B超诊断 B超扫描临床应用 X射线异物眼部定位精度

急性感染性腹泻血清IL-1β、IL-17、TNF-α水平与肠道菌群相关性

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医学动物防制 2024年第3期40卷 252-257页

作者：隋航烁刘伟鲁文靖李伟男张丽萍承德市中心医院营养科河北承德067000 承德市中心医院消化内科

目的探究急性感染性腹泻患者血清白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-17(interleukin-17,IL-17)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平与肠道菌群的相关性。方法选取148例急性感染性腹泻患者作为... 详细信息

目的探究急性感染性腹泻患者血清白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-17(interleukin-17,IL-17)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平与肠道菌群的相关性。方法选取148例急性感染性腹泻患者作为研究组,148例健康体检者作为对照组。对比研究组和对照组血清IL-1β、IL-17、TNF-α水平,并比较研究组不同血清IL-1β、IL-17、TNF-α水平下的肠道菌群,采用Pearson分析研究组血清IL-1β、IL-17、TNF-α水平与肠道菌群的相关性,通过受试者操作特征(receiver operating characteristic, ROC)曲线分析血清IL-1β、IL-17、TNF-α水平诊断急性感染性腹泻的价值。结果研究组的血清IL-1β、IL-17、TNF-α水平高于对照组,差异有统计学意义(t=27.405、11.562、11.390,P<0.05);血清IL-1β、IL-17和TNF-α联合诊断急性感染性腹泻的曲线下面积(area under the curve, AUC)为0.876,大于各指标单一诊断;急性感染性腹泻患者血清IL-1β、IL-17、TNF-α水平与双歧杆菌、乳酸菌呈负相关(r=-0.527、-0.613、-0.594、-0.536、-0.621、-0.589,P<0.05),与肠杆菌呈正相关(r=0.074、0.082、0.089,P<0.05)。结论急性感染性腹泻患者的血清IL-1β、IL-17、TNF-α水平升高,与患者肠道菌群含量存在密切相关性,且在急性感染性腹泻诊断方面有一定应用价值。

关键词：急性感染性腹泻白细胞介素-1β 白细胞介素-17 肿瘤坏死因子感染标志物肠道菌群