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超级马氏体不锈钢X3CrNiMo13-4泵轴开裂原因分析

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金属热处理 2019年第S1期44卷 402-408页

作者：左敦桂张忠伟赖云亭张国栋苏州热工研究院有限公司苏州215004

通过宏观检查、拉伸性能试验、硬度试验、金相检验和扫描电镜分析等实验,对超级马氏体不锈钢X3CrNiMo13-4前置给水泵轴发生开裂进行原因分析,试验研究结果表明,机械密封O型圈失效导致泵轴表面发生点腐蚀,进而在交变载荷作用下,裂纹在表... 详细信息

通过宏观检查、拉伸性能试验、硬度试验、金相检验和扫描电镜分析等实验,对超级马氏体不锈钢X3CrNiMo13-4前置给水泵轴发生开裂进行原因分析,试验研究结果表明,机械密封O型圈失效导致泵轴表面发生点腐蚀,进而在交变载荷作用下,裂纹在表面腐蚀坑处萌生并扩展,进而发生疲劳开裂。

关键词：辅助给水泵机械密封疲劳裂纹

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n型光伏组件的电性能测试技术研究

太阳能学报 2015年第6期36卷 1533-1538页

作者：陈喜平何涛张昌远张忠卫阮忠立秦涛涛杜军伟连云港神舟新能源有限公司连云港222100 上海神舟新能源发展有限公司上海201112

针对常规瞬态I-V测试仪（脉冲时间一般为5～20ms）在高效率、高电容的n型光伏组件测试时出现，I-V曲线失真，从而导致开路电压、填充因子、最大功率出现偏差的问题，从电池结构和测试机理上出发，分析产生这种偏差的原因，提出解决该问... 详细信息

针对常规瞬态I-V测试仪（脉冲时间一般为5～20ms）在高效率、高电容的n型光伏组件测试时出现，I-V曲线失真，从而导致开路电压、填充因子、最大功率出现偏差的问题，从电池结构和测试机理上出发，分析产生这种偏差的原因，提出解决该问题的关键方法。采用宽脉冲测试、分段测试等测试方法，对n型常规、IBC电池等n型光伏组件进行测试，研究不同测试方法和电池电容对n型光伏组件测试结果的影响，获得该类光伏组件电性能的精准测试方法，可解决n型高电容光伏组件的测试问题。

关键词：光伏组件电容效应脉冲时间电性能测试

晶圆制造双闭环Interbay物料运输系统性能分析模型

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工业工程与管理 2023年第3期28卷 135-144页

作者：吴立辉张中伟胡文博张洁上海应用技术大学机械工程学院上海201418 河南工业大学机电工程学院河南郑州450001 东华大学人工智能研究院上海201620

双闭环Interbay物料运输系统是300 mm晶圆制造系统至关重要的组成部分。为在设计阶段快速有效分析其运行性能,本文提出了一种扩展马尔可夫模型。该模型充分考虑了运输小车在外环、内环和捷径导轨关键节点的运行、堵塞、装卸晶圆卡等系... 详细信息

双闭环Interbay物料运输系统是300 mm晶圆制造系统至关重要的组成部分。为在设计阶段快速有效分析其运行性能,本文提出了一种扩展马尔可夫模型。该模型充分考虑了运输小车在外环、内环和捷径导轨关键节点的运行、堵塞、装卸晶圆卡等系统状态,抑制了多运输小车运行环境下的模型状态空间规模爆炸,提高了性能分析模型的准确性与运算效率。采用某晶圆制造企业实际生产数据,将扩展马尔可夫模型与仿真模型进行比较。结果表明:两者在空载运输小车到达时间间隔、系统搬运能力和运输小车利用率等关键指标方面相对误差值较小;扩展马尔可夫模型明显具有更高的分析效率。由此验证了提出的扩展马尔可夫模型用于双闭环Interbay系统性能分析是有效的。

关键词：晶圆制造 Interbay物料运输系统双闭环扩展马尔可夫模型性能分析

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嗜酸性实性和囊性肾细胞癌一例

中华放射学杂志 2021年第6期55卷 673-674页

作者：傅孙亚陈达巍张忠伟张玉琴郑建军宁波大学附属李惠利医院影像科 315040 宁波大学附属李惠利医院消化内科 315040 中国科学院大学宁波华美医院放射科 315010

本文报道1例50岁女性左肾嗜酸性实性和囊性肾细胞癌的影像表现。病灶呈类圆形囊实性,边界清晰,CT平扫实性成分呈等密度,增强肾皮质期及实质期持续渐进性强化,排泄期强化减退,强化程度均稍低于同期肾皮质,囊性部分无强化。MRI平扫实性部... 详细信息

本文报道1例50岁女性左肾嗜酸性实性和囊性肾细胞癌的影像表现。病灶呈类圆形囊实性,边界清晰,CT平扫实性成分呈等密度,增强肾皮质期及实质期持续渐进性强化,排泄期强化减退,强化程度均稍低于同期肾皮质,囊性部分无强化。MRI平扫实性部分T_(1)WI及T_(2)WI均呈稍低信号,DWI为高信号,增强表现类似CT强化。

关键词：癌肾细胞嗜酸性磁共振成像体层摄影术 X线计算机

Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： Lele REN Wei zhang Yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1:2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,while the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration

Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao zhang Ying FU Jun zhang School of Computer Science and Technology Beijing Institute of Technology Advanced Reasearch Institute of Multidisciplinary Science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Training Visualization Inverse problems Green products Noise reduction Pipelines Signal processing

三臂凿岩台车钻臂协同钻孔防碰撞路径规划研究

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隧道建设（中英文） 2023年第10期43卷 1801-1809页

作者：吕为盛崔孟豪姬会福张中伟河南工业大学机电工程学院河南郑州450001 河南农业大学烟草学院河南郑州450002

针对三臂凿岩台车3个钻臂协同钻孔时,由于路径规划不合理导致钻臂碰撞干涉,造成设备损坏、影响掘进施工效率的问题,提出一种基于改进人工势场法的钻臂协同钻孔防碰撞路径规划方法。首先,采用改进的D-H法建立三臂凿岩台车钻臂运动学模型... 详细信息

针对三臂凿岩台车3个钻臂协同钻孔时,由于路径规划不合理导致钻臂碰撞干涉,造成设备损坏、影响掘进施工效率的问题,提出一种基于改进人工势场法的钻臂协同钻孔防碰撞路径规划方法。首先,采用改进的D-H法建立三臂凿岩台车钻臂运动学模型,采用包络盒法对钻臂结构进行合理简化,建立碰撞检测数学模型;其次,对传统势场法中的势场函数进行重建,将势能引入钻臂各关节,保证势场可以约束钻臂的运动姿态;最后,以188孔位隧道掌子面为例,钻臂依据优化后的钻孔顺序进行作业,基于此对钻臂进行防碰撞路径规划仿真实验。仿真结果表明:1)基于距离最短钻孔顺序时中间钻臂与左右钻臂之间的最短距离分别为984.6、580.8 mm,均未发生碰撞干涉;2)基于关节变量最小钻孔顺序时中间钻臂与左右钻臂之间的最短距离分别为193.5、580.8 mm,此时考虑施工安全性及钻臂结构尺寸存在碰撞风险,故应选取距离最短钻孔顺序进行钻孔施工,以实现三臂凿岩台车多钻臂协同钻孔作业。

关键词：三臂凿岩台车防碰撞路径规划人工势场法钻臂碰撞干涉检测

Oxygen reduction electrocatalysis:From conventional to single-atomic platinum-based catalysts for proton exchange membrane fuel cells

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Frontiers in Energy 2024年第2期18卷 206-222页

作者： Cheng YUAN Shiming zhang Jiujun zhang Institute for Sustainable Energy/College of Sciences Shanghai UniversityShanghai 200444China

Platinum(Pt)-based materials are still the most efficient and practical catalysts to drive the sluggish kinetics of cathodic oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs).However,their catalysis and stability performance still need to be further improved in terms of corrosion of both carbon support and Pt catalyst particles as well as Pt loading *** on the developed synthetic strategies of alloying/nanostructuring Pt particles and modifying/innovating supports in developing conventional Pt-based catalysts,Pt single-atom catalysts(Pt SACs)as the recently burgeoning hot materials with a potential to achieve the maximum utilization of Pt are comprehensively reviewed in this *** design thoughts and synthesis of various isolated,alloyed,and nanoparticlecontained Pt SACs are *** single-atomic Pt coordinating with non-metals and alloying with metals as well as the metal-support interactions of Pt single-atoms with carbon/non-carbon supports are emphasized in terms of the ORR activity and stability of the *** advance further research and development of Pt SACs for viable implementation in PEMFCs,various technical challenges and several potential research directions are outlined.

关键词： oxygen reduction electrocatalysis Pt singleatom catalysts conventional Pt-based catalysts design thoughts and synthesis metal-support interactions

Value Iteration-Based Cooperative Adaptive Optimal Control for Multi-Player Differential Games With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 690-697页

作者： Yun zhang Lulu zhang Yunze Cai the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China

This paper presents a novel cooperative value iteration(VI)-based adaptive dynamic programming method for multi-player differential game models with a convergence *** players are divided into two groups in the learning process and adapt their policies *** method removes the dependence of admissible initial policies,which is one of the main drawbacks of the PI-based ***,this algorithm enables the players to adapt their control policies without full knowledge of others’ system parameters or control *** efficacy of our method is illustrated by three examples.

关键词： Adaptive dynamic programming incomplete information multi-player differential game value iteration