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Printed Circuit Board (PCB) Surface Micro Defect Detection Model Based on Residual Network with Novel Attention Mechanism

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Computers, Materials & Continua 2024年第1期78卷 915-933页

作者： Xinyu Hu defeng Kong Xiyang Liu Junwei Zhang Daode Zhang School of Mechanical Engineering Hubei University of TechnologyWuhan430068Chain

Printed Circuit Board(PCB)surface tiny defect detection is a difficult task in the integrated circuit industry,especially since the detection of tiny defects on PCB boards with large-size complex circuits has become one of the *** improve the performance of PCB surface tiny defects detection,a PCB tiny defects detection model based on an improved attention residual network(YOLOX-AttResNet)is ***,the unsupervised clustering performance of the K-means algorithm is exploited to optimize the channel weights for subsequent operations by feeding the feature mapping into the SENet(Squeeze and Excitation Network)attention network;then the improved K-means-SENet network is fused with the directly mapped edges of the traditional ResNet network to form an augmented residual network(AttResNet);and finally,the AttResNet module is substituted for the traditional ResNet structure in the backbone feature extraction network of mainstream excellent detection models,thus improving the ability to extract small features from the backbone of the target detection *** results of ablation experiments on a PCB surface defect dataset show that AttResNet is a reliable and efficient *** Torify the performance of AttResNet for detecting small defects in large-size complex circuit images,a series of comparison experiments are further *** results show that the AttResNet module combines well with the five best existing target detection frameworks(YOLOv3,YOLOX,Faster R-CNN,TDD-Net,Cascade R-CNN),and all the combined new models have improved detection accuracy compared to the original model,which suggests that the AttResNet module proposed in this paper can help the detection model to extract target *** them,the YOLOX-AttResNet model proposed in this paper performs the best,with the highest accuracy of 98.45% and the detection speed of 36 FPS(Frames Per Second),which meets the accuracy and real-time requirements for the detection of tiny defect

关键词： Neural networks deep learning ResNet small object feature extraction PCB surface defect detection

Iterative Model Predictive Control for Automatic Carrier Landing of Carrier-Based Aircrafts Under Complex Surroundings and Constraints

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Journal of Shanghai Jiaotong university(Science) 2024年第4期29卷 712-724页

作者： ZHANG Xiaotian HE defeng LIAO Fei College of Information Engineering Zhejiang University of TechnologyHangzhou310023China Aerospace Technology Institute China Aerodynamics Research and Development CenterMianyang621000SichuanChina

This paper considers the automatic carrier landing problem of carrier-based aircrafts subjected to constraints,deck motion,measurement noises,and unknown *** iterative model predictive control(MPC)strategy with constraints is proposed for automatic landing control of the ***,the long short-term memory(LSTM)neural network is used to calculate the adaptive reference trajectories of the *** the Sage-Husa adaptive Kalman filter and the disturbance observer are introduced to design the composite ***,an iterative optimization algorithm is presented to fast solve the receding horizon optimal control problem of MPC based on the Lagrange’s ***,some sufficient conditions are derived to guarantee the stability of the landing system in a closed loop with the ***,the simulation results of F/A-18A aircraft show that compared with the conventional MPC,the presented MPC strategy improves the computational efficiency by nearly 56%and satisfies the control performance requirements of carrier landing.

关键词： automatic carrier landing model predictive control(MPC) long short-term memory(LSTM)neural network stability computational efficiency

Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors

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International Journal of Mining Science and Technology 2024年第2期34卷 211-225页

作者： Xingsen Guo Ning Fan defeng Zheng Cuiwei Fu Hao Wu Yanjun Zhang Xiaolong Song Tingkai Nian State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Department of Civil Environmentaland Geomatic EngineeringUniversity College LondonLondon WC1E 6BTUnited Kingdom Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Civil Engineering and Architecture Wenzhou UniversityWenzhou 325035China Key Laboratory of Engineering and Technology for Soft Soil Foundation and Tideland Reclamation of Zhejiang Province Wenzhou 325035China Zhejiang International Science and Technology Cooperation Base of Ultra-soft Soil Engineering and Smart Monitoring Wenzhou 325035China School of Geography Liaoning Normal UniversityDalian 116029China China Railway First Survey and Design Institute Group Co. Ltd.Xi’an 710043China Department of Geotechnical Engineering Nanjing Hydraulic Research InstituteNanjing 210024China Wuhan Center China Geological Survey(Central South China Innovation Center for Geosciences)Wuhan 430205China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China

Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental ***,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine *** incidents have highlighted the substantial damage to pipelines due to ***,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant *** assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline *** study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact *** factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of ***,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with *** upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.

关键词： Deep-sea fluidized slides Pipes Impact forces Shear behavior of slides Interface contact conditions Spatial relation

CBF-Based Distributed Model Predictive Control for Safe Formation of Autonomous Mobile Robots

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Journal of Shanghai Jiaotong university(Science) 2024年第4期29卷 678-688页

作者： MU Jianbin YANG Haili HE defeng College of Information Engineering Zhejiang University of TechnologyHangzhou310023China

A distributed model predictive control(DMPC)method based on robust control barrier function(RCBF)is developed to achieve the safe formation target of multi-autonomous mobile robot systems in an uncertain disturbed *** first step is to analyze the safety requirements of the system during safe formation and categorize them into collision avoidance and distance connectivity *** constraints are designed based on collision avoidance and connectivity maintenance requirements,and security constraints are achieved through a ***,the specified safety constraints are integrated with the objective of forming a multi-autonomous mobile robot *** ensure safe control,the optimization problem is integrated with the DMPC ***,the RCBF-DMPC algorithm is proposed to ensure iterative feasibility and stability while meeting the constraints and expected *** experiments illustrate that the designed algorithm can achieve cooperative formation and ensure system security.

关键词： distributed model predictive control(DMPC) robust control barrier function(RCBF) autonomous mobile robot formation control collision avoidance

Dating Kimberlite Using Apatite U-Pb Geochronology: A Case Study from Diamond-Bearing Dikes in South China

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Journal of Earth Science 2024年第3期35卷 1059-1062页

作者： Jiawei Zhang Huan Wang defeng He Yuhua Zhu Kun Wang Yuan Qiu Guizhou Geological Survey Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang 550081China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Yanduzhongshi Geological Analysis Laboratory Ltd. Beijing 100080China State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Kimberlite,one of the deepest known magmatic rocks on Earth,offers valuable glimpses into the deep mantle composition(Woodhead et al.,2019),craton structure(Gardiner et al.,2020),global geodynamic variation(Tappe et al.,2018),and diamond formation(Giuliani et al.,2023).The accurate determination of the emplacement of this special rock is crucial for revealing such ***,dating kimberlite is challenging due to its silica-poor,volatile-rich,strongly altered,and hybrid nature(Mitchell et al.,2019).Zircon is unsuitable for dating kimberlite and related rocks due to its preference for crystallizing in intermediate to felsic melts(Gervasoni et al.,2016)rather than silica-poor *** if present,zircon is prone to Pb loss through hydrothermal alteration(Zi et al.,2022)in a volatile-rich system like kimberlitic magmas.

关键词： dating magma alteration

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缅甸英雄岛始新世孢粉组合及其古环境意义

石油实验地质 2024年第1期46卷 136-145页

作者：史德锋祝幼华中海石油(中国)有限公司海南分公司海口570312 中国科学院南京地质古生物研究所南京210008

为配合中缅合作的M区块油气勘探,确定该区块英雄岛含油气地层时代与沉积环境,对缅甸英雄岛R-3井2562~2844 m井段10个烃源岩样品进行了孢粉实验分析。通过观察,在每个样品中均发现了较丰富的孢粉化石,共鉴定出85属135种或未定种。该井段... 详细信息

为配合中缅合作的M区块油气勘探,确定该区块英雄岛含油气地层时代与沉积环境,对缅甸英雄岛R-3井2562~2844 m井段10个烃源岩样品进行了孢粉实验分析。通过观察,在每个样品中均发现了较丰富的孢粉化石,共鉴定出85属135种或未定种。该井段的孢粉化石以Momipites和Quercoidites含量丰富,始新世常见分子Sabalpolllenites areolatus断续出现,并见有特征分子Schizaeoisporites eocenicus为主要特征,根据孢粉特征分子和优势属种的分布规律,命名为Schizaeoisporites eocenicus-Quercoidites-Momipites-Sabalpollenites areolatus组合;对比相同井段有孔虫和钙质超微化石的分布时代,推测当前的孢粉组合时代为中晚始新世。依据孢粉组合面貌,对照我国油气区古近纪—新近纪孢粉序列的数据统计结果,系统研究后所建立的划分孢粉植物类型、气温带和干湿度带的3个模式,并结合本钻井其他孢型化石分布特征,认为研究区中晚始新世地层为近海陆地环境,北亚热带、暖温带湿润型古气候沉积。

关键词：孢粉组合古环境中晚始新世英雄岛缅甸

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违约金司法酌减的依据及其限度

法学 2024年第4期 110-123页

作者：许德风北京大学法学院

与合同中的本给付义务不同,支付违约金的义务系因违反本给付义务所产生的次给付义务。出于对意思自治的尊重,裁判者在判断应否酌减违约金时,应首先区分本给付义务与次给付义务,避免干涉当事人经充分协商后所达成的有关本给付义务的约定... 详细信息

与合同中的本给付义务不同,支付违约金的义务系因违反本给付义务所产生的次给付义务。出于对意思自治的尊重,裁判者在判断应否酌减违约金时,应首先区分本给付义务与次给付义务,避免干涉当事人经充分协商后所达成的有关本给付义务的约定。酌减违约金的最终目的在于贯彻公序良俗与诚实信用等原则,维护合同公正。在具体判断标准上,应对合同进行体系解释,充分考虑违约金约定与合同其他条款的关系,维护非违约方关于合同履行的全部合法利益,对超过本给付义务总额的违约金和不区分情形一揽子适用的违约金给予特别关注。私法并不当然排斥惩罚,在确定违约金应否酌减时,裁判者既应维护合同公正,也应重视违约金预防、惩罚违约行为及鼓励守约的社会功能。对于法律特别允许的惩罚性措施如定金约定等,原则上不应干涉或调整。

关键词：违约金司法酌减定金本给付义务次给付义务惩罚性违约金

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日间手术麻醉规范化管理策略

实用医学杂志 2024年第3期40卷 283-288页

作者：孙德峰大连医科大学附属第一医院麻醉科辽宁大连116011

日间手术具有床位周转快、患者满意度高、医疗费用少、院内感染率低等优势,是目前国内外大力探索和发展的一种手术模式。安全是日间手术开展的底线,舒适是日间手术的核心追求,二者的保障均离不开对高质量的围术期麻醉管理。因此,在快速... 详细信息

日间手术具有床位周转快、患者满意度高、医疗费用少、院内感染率低等优势,是目前国内外大力探索和发展的一种手术模式。安全是日间手术开展的底线,舒适是日间手术的核心追求,二者的保障均离不开对高质量的围术期麻醉管理。因此,在快速周转的日间手术模式下,本文就如何实施规范化的麻醉管理策略,分别从日间手术麻醉临床路径的制定、硬件设施以及人员的配备,麻醉术前评估与术前准备,麻醉方式的选择,围术期疼痛管理,术后恶心呕吐(postoperative nausea and vomiting,PONV)管理,麻醉后监测治疗,术后随访几方面加以阐述。

关键词：日间手术麻醉规范化管理围术期疼痛术后恶心呕吐

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首采工作面过浅埋深薄煤区安全回采技术研究

矿业研究与开发 2024年第4期44卷 25-32页

作者：鲁德丰阚磊内蒙古智能煤炭有限责任公司 P内蒙古鄂尔多斯市010400

为解决浅埋深、薄煤层等特殊地质条件易造成工作面溃水、溃砂、压架、冒顶等安全事故的问题。以麻地梁煤矿特殊地质条件及生产方式为背景,提出了以“破底割煤”“只采不放”为核心的首采工作面过浅埋深、薄煤区安全回采技术,并在工作面... 详细信息

为解决浅埋深、薄煤层等特殊地质条件易造成工作面溃水、溃砂、压架、冒顶等安全事故的问题。以麻地梁煤矿特殊地质条件及生产方式为背景,提出了以“破底割煤”“只采不放”为核心的首采工作面过浅埋深、薄煤区安全回采技术,并在工作面矿压显现及两巷超前支承压力分布等方面进行了应用效果分析。结果表明,工作面区域周期来压呈现出显著的“空间阶段性”,强烈来压主要出现在工作面的中部区域;相较于浅埋深区域,薄煤区及重叠区周期来压步距及持续距离增加,“局部来压”明显,但来压强度均处于较低水平;工作面过浅埋深、薄煤层区域时,巷道围岩收敛速度慢、变形量小,煤层顶板无显著离层,0~3m浅基点及3~7m深基点处相对离层量均不超过4mm,超前支承压力不明显,工作面对两巷超前支撑压力影响范围为40m,平均峰值强度为17.3MPa。研究结果有效验证了该安全回采技术的合理性和可靠性。

关键词：安全回采技术浅埋煤层薄煤层矿压显现规律