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Portable Structure Surface Crack Detection System Based on Android Platform

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Wuhan University Journal of Natural Sciences 2024年第2期29卷 154-164页

作者： WANg Huifeng PENg haonan TANg Yu gUAN Yueyuan LIANg Yaru WANg Lisha ZHAO Yu WANg Xiaoyan gAO Rong HUANg He School of Electronics and Control Engineering Chang'an UniversityXi'an 710000ShaanxiChina Research Institute of Highway Ministry of Transport Beijing 100000China State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610000SichuanChina Highway School Chang'an UniversityXi'an 710000ShaanxiChina

Cracks,potholes,and other defects often occur on infrastructure such as bridges,among which cracks are one of the most frequent *** have diverse shapes and are difficult to *** manual inspection methods are inefficient and have low accuracy,while automated inspection machines are bulky and inconvenient to carry and *** on the shortcomings of existing detection technologies,this paper proposes a portable structural surface crack detection system based on the Android platform using a portable hand-held image acquisition *** system captures cracks on the structure's surface and obtains high-definition crack ***,these images are transmitted to portable smartphone terminals through ***,the image is pre-processed using weighted averaging,grayscale linear transformation,and adaptive median ***,the improved Canny edge detection algorithm is applied to identify crack information,and the edge segmentation algorithm is used to determine the crack ***,based on camera calibration,the pixels are converted into the length data required for actual *** results show that the system is easy to operate,and it not only has crack storage and tracking functions,but also can effectively measure the crack width on the surface of *** measurement accuracy of this system reaches the sub-pixel level,and in actual testing,compared with the crack width gauge,the maximum relative error does notexceed6.25%.

关键词： structural crack portable image processing detection accuracy crack parameter

Spectroscopy and molecule opacity investigation on excited states of SiS

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Chinese Physics B 2024年第5期33卷 381-387页

作者：李瑞吕浩男桑纪群刘晓华梁桂颖吴勇 College of Teacher Education Qiqihar UniversityQiqihar 161006China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China Department of Physics College of ScienceQiqihar UniversityQiqihar 161006China School of Data Science and Artificial Intelligence Jilin Engineering Normal UniversityChangchun 130052China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100084China

The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many *** to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is *** obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been *** method is used to calculate the potential energy curves(PECs)of the 18Λ–S states corresponding to the lowest dissociation limit of *** core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI *** on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental *** transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI *** addition,the abrupt variations of the DMs for the 1^(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic *** opacity of SiS at a pressure of 100 atms is presented across a series of *** increasing temperature,the expanding population of excited states blurs the band boundaries.

关键词： SiS opacity excited state spectroscopic constant configuration interaction

The Impact of Bias Row Noise to Photometric Accuracy:Case Study Based on a Scientific CMOS Detector

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Research in Astronomy and Astrophysics 2024年第2期24卷 228-246页

作者： Li Shao Hu Zhan Chao Liu haonan Chi Qiuyan Luo Huaipu Mu Wenzhong Shi National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China University of Chinese Academy of Sciences Beijing 100049China Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 100875China

We tested a new model of CMOS detector manufactured by the gpixel Inc,for potential space astronomical *** laboratory,we obtain some bias images under the typical application *** these bias images,clear random row noise pattern is *** row noise also contains some characteristic spatial *** quantitatively estimated the impact of this feature to photometric measurements,by making simulated *** compared different bias noise types under strict parameter *** result shows the row noise will significantly deteriorate the photometric *** effectively increases the readout noise by a factor ***,if it is properly removed,the image quality and photometric accuracy will be significantly improved.

关键词： instrumentation detectors-methods statistical-techniques image processing

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串列双颗粒绕流传热大涡模拟研究

工程热物理学报 2024年第2期45卷 488-493页

作者：贾浩楠杨剑王秋旺西安交通大学热流科学与工程教育部重点实验室西安710049

本文采用大涡模拟的方法对串列双颗粒绕流的流动和换热特性进行了研究,分析了前后颗粒的阻力系数和努塞尔数随时间变化的关系,此外,对比分析了光滑双颗粒和凹坑双颗粒的流动和换热特性。研究发现不同表面结构的双颗粒绕流时的流动和换... 详细信息

本文采用大涡模拟的方法对串列双颗粒绕流的流动和换热特性进行了研究,分析了前后颗粒的阻力系数和努塞尔数随时间变化的关系,此外,对比分析了光滑双颗粒和凹坑双颗粒的流动和换热特性。研究发现不同表面结构的双颗粒绕流时的流动和换热特性存在明显差异,且相比与光滑双颗粒,凹坑双颗粒的前后颗粒分别减小18.27%和3.08%的流动阻力,同时换热性能分别提升14.26%和7.77%。凹坑结构呈现出更优异的流动和换热性能。

关键词：串列双颗粒凹坑结构阻力减小换热强化大涡模拟

Chinese expert consensus on the clinical application of drugcoated balloon(2^(nd) Edition)

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Journal of geriatric Cardiology 2024年第2期21卷 135-152页

作者： The Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon(2^(nd)Edition) Jun-Bo gE Yun-Dai CHEN 不详 Zhongshan Hospital Fudan University Chinese PLA general Hospital

Percutaneous coronary interventions have progressed through the era of plain balloon dilation, bare-metal stent insertion to drug-eluting stent treatment, which has significantly reduced the acute occlusion and restenosis rates of target vessels and improved patient prognosis, making drug-eluting stents the mainstream interventional treatment for coronary artery disease. In recent years, drug-coated balloons(DCBs) have become a new treatment strategy for coronary artery disease, and the drugs used in the coating and the coating technology have progressed in the past years. Without permanent implant, a DCB delivers antiproliferative drugs rapidly and uniformly into the vessel wall via the excipient during a single balloon dilation. Many evidence suggests that DCB angioplasty is an effective measure for dealing with in-stent restenosis and de novo lesions in small coronary *** more clinical studies are published, new evidence is emerging for the use of DCB angioplasty in a wide range of coronary diseases, and the indications are expanding internationally. Based on the latest research from China and elsewhere, the Expert Writing Committee of the Chinese Expert Consensus on Clinical Applications of Drug-Coated Balloon has updated the previous DCB consensus after evidence-based discussions and meetings in terms of adequate preparation of in-stent restenosis lesions, expansion of the indications for coronary de novo lesions, and precise guidance of DCB treatment by intravascular imaging and functional evaluation.

关键词： balloon drugs dealing

Sliding Mode-Based Active Disturbance Rejection Control for 3D Overhead Crane with Payload Hoisting/Lowering

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Sliding Mode-Based Active Disturbance Rejection Control for ...

第35届中国过程控制会议

作者： Shourui Wang Wuyin Jin haonan Zhang An Wang Wenke Chen School of Mechanical and Electronical Engineering Lanzhou University of Technology

Based on the sliding mode control(SMC) and active disturbance rejection control(ADRC) theory, the controller design problem for a three-dimensional(3D) overhead crane with payload hoisting/lowering is investigated in this work. Firstly, a virtual controlled model is constructed by combining the actuated displacement state with the underactuated angle state, considering the complex situation of the overhead crane coupling multi-state. Secondly, a linear extended state observer(LESO) is designed based on the reconstructed virtual model, and a SMC method is proposed based on the observer output, with the stability of the closed-loop system being proved using Lyapunov theory. Finally, the effectiveness of the proposed control method is verified through the execution of three sets of simulation conditions.

关键词： 3D overhead crane sliding mode control active disturbance rejection control payload hoisting/lowering

来源： cnki会议评论

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cnki会议

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横向持股的反垄断规制路径研究

社会科学战线 2024年第3期345卷 202-215页

作者：王健雷昊楠浙江理工大学法政学院浙江杭州310018 武汉大学法学院湖北武汉430072

20世纪末,随着全球金融监管环境的宽松与多元化投资的流行,横向持股迎来了发展契机。作为风险分散、收益稳定的新型投资方式,横向持股会对市场竞争造成损害,故需要对此进行反垄断规制。然而,目前各国针对横向持股的反垄断规制的路径较... 详细信息

20世纪末,随着全球金融监管环境的宽松与多元化投资的流行,横向持股迎来了发展契机。作为风险分散、收益稳定的新型投资方式,横向持股会对市场竞争造成损害,故需要对此进行反垄断规制。然而,目前各国针对横向持股的反垄断规制的路径较为单一,无法涵盖所有可能产生排除、限制竞争效果的横向持股。为此,中国应当以传统反垄断规制路径为基础,包括经营者集中制度、垄断协议规制制度与滥用共同市场支配地位制度,进一步构建横向持股反垄断规制的多元化路径,具体表现为导入双维度的反垄断规制路径、建立寡头垄断名单制度与规定横向持股安全港规则。

关键词：横向持股竞争损害反垄断规制反垄断法

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气候智慧型林业发展现状及启示

世界林业研究 2024年第3期37卷 10-15页

作者：石浩男赵荣中国林业科学研究院林业科技信息研究所北京100091

为发挥森林在应对气候变化方面的重要作用,欧美学者提出了气候智慧型林业(climate-smart forestry)的概念和理论,得到欧美社会各界广泛关注。文中从核心概念、主要目标、与其他森林经营模式的关系、应用范畴、发展重点5个方面解释气候... 详细信息

为发挥森林在应对气候变化方面的重要作用,欧美学者提出了气候智慧型林业(climate-smart forestry)的概念和理论,得到欧美社会各界广泛关注。文中从核心概念、主要目标、与其他森林经营模式的关系、应用范畴、发展重点5个方面解释气候智慧型林业的概念,梳理气候智慧型林业的发展脉络和研究现状,讨论气候智慧型林业理念存在的问题,针对问题提出潜在的研究方向。我国重视林业在实现碳中和碳达峰、促进乡村振兴等多方面的作用。气候智慧型林业与我国林业政策方向相符,对加强森林经营、支持产业发展、发展林业金融、促进国家合作等具有启示意义。

关键词：气候智慧型林业森林经营森林碳汇林业经济林业政策

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2A tokamak

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Plasma Science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2A Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2A *** 20-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2026 mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82%at 122 nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~280 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2A campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet