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Process Optimization for Cerium Oxide Based Conversion Coating of AZ91D Magnesium Alloy at Room Temperature

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稀有金属材料与工程 2012年第S1期41卷 243-246页

作者： Chen Dongchu Wu Jianfeng ye shulin Foshan Univ Sch Sci Foshan 528000 Peoples R China

The Ce2SO4/H2O2 containing solution is used to prepare a chrome-free cerium oxide based chemical conversion coating on AZ91D magnesium alloy at room temperature,and an orthogonal experiment was carried out to optimize the treating *** effect of preparing parameters on the coating growth and the corrosion resistance were *** was found that H2O2 is the dominant influence factor on the coating weight gain in the orthogonal experiment,with Ce(SO4)2 coming next and immersion time having the least impact,while the most dominant influence factor on the corrosion resistance is Ce(SO4)2,with H2O2 coming next and immersion time having the least *** coating has the best corrosion resistance,treated in the solution of 10 g/l Ce(SO4)2 and 12 ml/l H2O2 for 4 *** was adopted to study the micro-morphology of the conversion coating on magnesium alloy surface The prolonged immersion time duration or the increased concentration of Ce(SO4)2 and H2O2 will increase the coating thickness,but tiny cracks appears resulted from the fast coating deposition.

关键词： magnesium alloy cerium conversion coating chrome-free room temperature

基于改进SSA-DNN的工业机器人定位误差补偿研究

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自动化应用 2024年第3期65卷 9-14页

作者：周雨祺叶树林杨林佛山科学技术学院机电工程与自动化学院广东佛山528000 佛山智能装备技术研究院广东佛山528200

针对工业机器人定位精度不高和传统误差补偿方法复杂的问题,提出了一种改进SSA-DNN神经网络的工业机器人定位误差补偿模型。首先,在笛卡尔空间优化空间网格分割采样规划,获得目标点位与其定位误差的规律;其次,提出一种基于Tent混沌映射... 详细信息

针对工业机器人定位精度不高和传统误差补偿方法复杂的问题,提出了一种改进SSA-DNN神经网络的工业机器人定位误差补偿模型。首先,在笛卡尔空间优化空间网格分割采样规划,获得目标点位与其定位误差的规律;其次,提出一种基于Tent混沌映射的ISSA算法,结合Levy飞行机制,提升SSA算法的搜索能力与加快收敛速度;最后,建立ISSA-DNN定位误差补偿模型,为验证补偿模型的有效性,以自由度工业机器人为对象,与其他模型进行对比实验,实现了对机器人实际点位的补偿,提高了机器人的定位精度。结果表明,在机器人定位误差补偿方面,与DNN与SSA-DNN等神经网络模型相比,ISSA-DNN神经网络模型具有更高的补偿精度和稳定性。

关键词：误差补偿采样优化混沌映射 Levy飞行

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海上风电安装平台升降系统同步控制研究

中国修船 2024年第2期37卷 55-60页

作者：刘伟叶树林刘会涛佛山科学技术学院机电工程与自动化学院广东佛山528000 广东精铟海洋工程股份有限公司广东佛山528000

文章针对海上风电安装平台的升降系统在升/降过程中受到扰动后同步性能变差的问题,设计了基于幂次趋近律的滑模变结构控制方法,用来提高升降系统的同步性能和抗干扰能力。文章采用滑模控制器设计转速环控制器,应用偏差耦合同步控制策略... 详细信息

文章针对海上风电安装平台的升降系统在升/降过程中受到扰动后同步性能变差的问题,设计了基于幂次趋近律的滑模变结构控制方法,用来提高升降系统的同步性能和抗干扰能力。文章采用滑模控制器设计转速环控制器,应用偏差耦合同步控制策略,对同步误差控制器作出改进。利用Simulink建立了4台异步电机的同步控制模型,分别验证了单电机的滑模控制和多电机的滑模同步控制的控制效果,并根据仿真图像分析,得出了以下结论,即对于单电机控制,滑模控制的效果较PI控制器具有更高的鲁棒性;对于多电机同步控制,滑模同步误差控制器相较传统偏差耦合控制策略,同步精度高,且鲁棒性强。

关键词：升降系统多电机同步控制矢量控制偏差耦合滑模控制

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王沛论治乳腺癌经验

中华中医药杂志 2024年第3期39卷 1294-1297页

作者：江洋谭曦叶书林钟元涛弓铭刘传波胡凯文北京中医药大学深圳医院深圳518000 北京中医药大学东方医院北京100078

王沛教授认为乳腺癌的形成是由于肝气不疏,情志不遂,进而气机壅滞上焦,痰浊凝集不化,与癌毒相结合,遂成形而结块。治疗上,应以调畅气机,疏肝解郁为本,化痰散瘀,清热解毒为要。用药上,辨病与辨证相结合,内治与外治相结合,自拟瓜蒌五物汤... 详细信息

王沛教授认为乳腺癌的形成是由于肝气不疏,情志不遂,进而气机壅滞上焦,痰浊凝集不化,与癌毒相结合,遂成形而结块。治疗上,应以调畅气机,疏肝解郁为本,化痰散瘀,清热解毒为要。用药上,辨病与辨证相结合,内治与外治相结合,自拟瓜蒌五物汤为基础方,辅以虫类药,小毒药以毒攻毒,补脾肾先后天之本,在治疗上收取较好疗效。

关键词：乳腺癌疏肝解郁化痰散瘀名医经验王沛

舞台上的科幻现实:艾克本的机器人剧作及其意义

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戏剧艺术 2023年第1期 174-184页

作者：叶书林上海戏剧学院戏文系

人们历来认为戏剧反映生活,机器人的出现却说明戏剧也可以有先于生活的预见性。当机器人站上舞台,戏剧创作的趋势之一是在科幻的背景下探讨现实。剧作家用想象创造了各种类型的机器人角色,从新的视角审视新的问题,追问人类的关系和境遇... 详细信息

人们历来认为戏剧反映生活,机器人的出现却说明戏剧也可以有先于生活的预见性。当机器人站上舞台,戏剧创作的趋势之一是在科幻的背景下探讨现实。剧作家用想象创造了各种类型的机器人角色,从新的视角审视新的问题,追问人类的关系和境遇。戏剧也因此扩展了对现实的探索维度,提供了一种观察社会与人类自省的陌生目光。英国当代剧作家艾伦·艾克本的《从头开始》等剧作是此类作品中的几个范例。

关键词：人机关系机器人戏剧艾伦·艾克本从头开始

Observing the collapse of super-Bloch oscillations in strong-driving photonic temporal lattices

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Advanced Photonics 2024年第4期6卷 14-24页

作者： Xinyuan Hu shulin Wang Chengzhi Qin Chenyu Liu Lange Zhao Yinglan Li Han ye Weiwei Liu Stefano Longhi Peixiang Lu Bing Wang Huazhong University of Science and Technology School of PhysicsWuhan National Laboratory for OptoelectronicsWuhanChina Wuhan Institute of Technology Hubei Key Laboratory of Optical Information and Pattern RecognitionWuhanChina Politecnico di Milano Dipartimento di FisicaMilanoItaly IFISC(UIB-CSIC) Instituto de Fisica Interdisciplinary Sistemas ComplejosPalma de MallorcaSpain

Super-Bloch oscillations(SBOs)are amplified versions of direct current(dc)-driving Bloch oscillations realized under the detuned dc-and alternating current(ac)-driving electric fields.A unique feature of SBOs is the coherent oscillation inhibition via the ac-driving renormalization effect,which is dubbed as the collapse of ***,previous experimental studies on SBOs have only been limited to the weak ac-driving regime,and the collapse of SBOs has not been ***,by harnessing a synthetic temporal lattice in fiber-loop systems,we push the ac-field into a strong-driving regime and observe the collapse of SBOs,which manifests as the oscillation-trajectory localization at specific ac-driving amplitudes and oscillation-direction flip by crossing collapse *** adopting arbitrary-wave ac-driving fields,we also realize generalized SBOs with engineered collapse ***,we exploit the oscillation-direction flip features to design tunable temporal beam routers and *** initiate and demonstrate the collapse of SBOs,which may feature applications in coherent wave localization control for optical communications and signal processing.

关键词： super-Bloch oscillations band collapse ac-driving renormalization effect photonic temporal lattices strong-driving regime

Investigations of Water Flow Behaviors Induced by Local Temperature Variations through a Single Rough Fracture for the Enhanced Geothermal Systems

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Journal of Thermal Science 2024年第3期33卷 1055-1064页

作者： LI Jiawei ye Lin Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

In recent years,Enhanced Geothermal System(EGS)technologies have been applied to the geothermal resources production in the Hot Dry Rock(HDR).The core of EGS technologies is to adopt hydraulic fracturing in the reservoir to create a connected network of discrete fractures with the consideration of water as a working fluid for hydraulic fracturing and heat *** paper investigates the characteristics of water flow behaviors through a single rough fracture under different temperature and pressure conditions.A single fracture model with rough fracture surfaces is constructed and then characterized,and influences of the anisotropic factor on the average tortuosity and frictional resistance coefficient of water flow through a single fracture with rough surfaces have been compared and *** consideration of other impacting factors(temperature,pressure,fracture roughness),the impact of mass flow rate has also been *** simulation results present that changes of average tortuosity for water flow through a single rough facture are mainly affected by *** can be observed that higher temperature leads to larger average tortuosity but the frictional resistance coefficient shows an opposite *** for pressure conditions,it is found that effects of pressure on average tortuosity and frictional resistance coefficient is very small,which can be neglected under high pressure ***,the average tortuosity shows a progressively linear relationship with the mass flow *** the contrary,the frictional resistance coefficient has a negative relationship with the mass flow *** is revealed that when the mass flow rate reaches a critical point,the influences of temperature on the frictional resistance coefficient will be *** of single rough fractures with different anisotropic factors show that values of average tortuosity and frictional resistance coefficient have positive relationships with the increase

关键词： single rough fracture tortuosity frictional resistance enhanced geothermal system

Path-Dependent Progressive Failure Analysis for 3D-Printed Continuous Carbon Fibre Reinforced Composites

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 84-93页

作者： Yuan Chen Lin ye School of System Design and Intelligent Manufacturing(SDIM) Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Intelligent Manufacturing for Continuous Carbon Fibre Reinforced Composites Southern University of Science and TechnologyShenzhen 518055China

In order to predict the damage behaviours of 3D-printed continuous carbon fibre(CCF)reinforced composites,when additional short carbon fibre(SCF)composite components are employed for continuous printing or special functionality,a novel path-dependent progressive failure(PDPF)numerical approach is ***,a progressive failure model using Hashin failure criteria with continuum damage mechanics to account for the damage initiation and evaluation of 3D-printed CCF reinforced polyamide(PA)composites is developed,based on actual fibre placement trajectories with physical measurements of 3D-printed CCF/PA ***,an elastic-plastic model is employed to predict the plastic damage behaviours of SCF/PA ***,the accuracy of the PDPF model was validated so as to study 3D-printed CCF/PA composites with either negative Poisson's ratio or high *** results demonstrate that the proposed PDPF model can achieve higher prediction accuracies in mechanical properties of these 3D-printed CCF/PA *** analyses show that the stress distribution is generally aggregated in the CCF areas along the fibre placement paths,and the shear damage and matrix tensile/compressive damage are the key damage *** study provides a new approach with valuable information for characterising complex 3D-printed continuous fibre-matrix composites with variable mechanical properties and multiple constituents.

关键词： 3D printing Continuous carbon fibre Modelling Energy absorption Negative Poisson's ratio

A modified stochastic model for LS+AR hybrid method and its application in polar motion short-term prediction

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Geodesy and Geodynamics 2024年第1期15卷 100-105页

作者： Fei ye Yunbin Yuan State Key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China BeiDou High-precision Satellite Navigation and Location Service Hunan Engineering Research Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China Hunan Continuously Operating Reference Stations(HNCORS)Data Center Hunan Institute of Geomatics Sciences and TechnologyChangsha 410007China

Short-term(up to 30 days)predictions of Earth Rotation Parameters(ERPs)such as Polar Motion(PM:PMX and PMY)play an essential role in real-time applications related to high-precision reference frame ***,least squares(LS)+auto-regressive(AR)hybrid method is one of the main techniques of PM ***,the weighted LS+AR hybrid method performs well for PM short-term ***,the corresponding covariance information of LS fitting residuals deserves further exploration in the AR *** this study,we have derived a modified stochastic model for the LS+AR hybrid method,namely the weighted LS+weighted AR hybrid *** using the PM data products of IERS EOP 14 C04,the numerical results indicate that for PM short-term forecasting,the proposed weighted LS+weighted AR hybrid method shows an advantage over both the LS+AR hybrid method and the weighted LS+AR hybrid *** to the mean absolute errors(MAEs)of PMX/PMY sho rt-term prediction of the LS+AR hybrid method and the weighted LS+AR hybrid method,the weighted LS+weighted AR hybrid method shows average improvements of 6.61%/12.08%and 0.24%/11.65%,***,for the slopes of the linear regression lines fitted to the errors of each method,the growth of the prediction error of the proposed method is slower than that of the other two methods.

关键词： Stochastic model LS+AR Short-term prediction The earth rotation parameter(ERP) Observation model