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Defence Technology（防务技术） 2024年第2期32卷 209-221页

作者： Mingming Wang Linfang qian Guangsong Chen Tong Lin Junfei Shi shijie Zhou Nanjing University of Science and Technology Nanjing 210094JiangsuChina Northwest Institute of Mechanical and Electrical Engineering Xianyang 712099ShaanxiChina Nanjing Vocational University of Industry Technology Nanjing 210023JiangsuChina

This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted ***,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the ***,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test ***,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile *** engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is *** results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle.

关键词： Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method

Enhancing Diagnosis and Treatment Adjustments for Travelers Infected with Burkholderia pseudomallei:A Case Report-Beijing Municipality,China,June 2023

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China CDC weekly 2024年第25期6卷 614-616页

作者： shijie Li Yushan He Yiyang Mao Jun Liu Wenmiao Xu Suyun qian Quan Wang Pediatric Intensive Care Unit Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina Capital Medical University BeijingChina

Summary What is already known about this topic?Burkholderia pseudomallei(BP)infection leads to melioidosis,a tropical disease endemic to coastal provinces of southern *** in nonendemic areas,do not commonly consider this disease as a primary differential diagnosis for febrile *** is added by this report?This article discusses a case of melioidosis in Northern *** patient,who had recently visited a Southeast Asian region with high melioidosis prevalence,fell ill after exposure to contaminated *** disease progressed quickly and with *** are the implications for public health practice?Healthcare workers need to remain vigilant regarding travel-related diseases for accurate differential diagnosis and to provide timely and effective treatment,especially for patients with recent travel history or symptoms during travel.

关键词： diagnosis China. travel

Physics-informed deep learning for fringe pattern analysis

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Opto-Electronic Advances 2024年第1期7卷 4-15页

作者： Wei Yin Yuxuan Che Xinsheng Li Mingyu Li Yan Hu shijie Feng Edmund Y.Lam qian Chen Chao Zuo Smart Computational Imaging Laboratory(SCILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart Computational Imaging Research Institute(SCIRI)of Nanjing University of Science and Technology Nanjing 210019China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing 210094China Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong Kong SAR 999077China

Recently,deep learning has yielded transformative success across optics and photonics,especially in optical *** neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe ***,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning *** this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) *** parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning *** by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end *** results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during *** proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.

关键词： optical metrology deep learning physics-informed neural networks fringe analysis phase retrieval

Modeling study of solid-particle erosion with consideration of particle velocity dependent model parameters

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 243-262页

作者： shijie qian Kuiying Chen Rong Liu Ming Liang Department of Mechanical Engineering University of Ottawa 770 King Edward Avenue OttawaONK1N 6N5Canada Institute for Aerospace Research National Research Council Canada 1200 Montreal Road OttawaONK1A 0R6Canada Department of Mechanical and Aerospace Engineering Carleton University 1125 Colonel By Drive OttawaONK1S 5B6Canada

An advanced erosion model that correlates two model parameters—the energies required to remove unit mass of target material during cutting wear and deformation wear,respectively,with particle velocity,particle size and density,as well as target material properties,is *** model is capable of predicting the erosion rates for a material under solid-particle impact over a specific range of particle velocity at the impingement angle between 0◦and 90◦,provided that the experimental data of erosion rate for the material at a particle velocity within this range and at impingement angles between 0◦and 90◦are *** proposed model is applied on three distinct types of materials:aluminum,perspex and graphite,to investigate the dependence behavior of the model parameters on particle velocity for ductile and brittle *** predicted model parameters obtained from the model are validated by the experimental data of aluminum plate under Al2O3 particle *** significance and limitation of the model are discussed;possible improvements on the model are suggested.

关键词： Solid-particle erosion particle impact velocity particle impingement angle cutting wear deformation wear erosion rate

Fluorine-Doped High-Performance Li_6PS_5Cl Electrolyte by Lithium Fluoride Nanoparticles for All-Solid-State Lithium-Metal Batteries

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Transactions of Tianjin University 2024年第3期30卷 250-261页

作者： Xiaorou Cao shijie Xu Yuzhe Zhang Xiaohu Hu Yifan Yan Yanru Wang Haoran qian Jiakai Wang Haolong Chang Fangyi Cheng Yongan Yang Institute of Molecular Plus School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

All-solid-state lithium-metal batteries(ASSLMBs)are widely considered as the ultimately advanced lithium batteries owing to their improved energy density and enhanced safety *** various solid electrolytes,sulfide solid electrolyte(SSE)Li_(6)PS_(5)Cl has garnered significant ***,its application is limited by its poor cyclability and low critical current density(CCD).In this study,we introduce a novel approach to enhance the performance of Li_(6)PS_(5)Cl by doping it with fluorine,using lithium fluoride nanoparticles(LiFs)as the doping *** F-doped electrolyte Li_(6)PS_(5)Cl-0.2LiF(nano)shows a doubled CCD,from 0.5 to 1.0 mA/cm~2 without compromising the ionic conductivity;in fact,conductivity is enhanced from 2.82 to 3.30 mS/cm,contrary to the typical performance decline seen in conventionally doped Li_(6)PS_(5)Cl *** symmetric Li|SSE|Li cells,the lifetime of Li_(6)PS_(5)Cl-0.2LiF(nano)is 4 times longer than that of Li_(6)PS_(5)Cl,achieving 1500 h vs.371 h under a charging/discharging current density of 0.2 mA/cm~*** Li|SSE|LiNbO_3@NCM721 full cells,which are tested under a cycling rate of 0.1 C at 30℃,the lifetime of Li_(6)PS_(5)Cl-0.2LiF(nano)is four times that of Li_(6)PS_(5)Cl,reaching 100 cycles vs.26 ***,the doping of nano-LiF off ers a promising approach to developing high-performance Li_(6)PS_(5)Cl for ASSLMBs.

关键词： Sulfide solid electrolyte All-solid-state lithium batteries Li_6PS_5Cl Lithium fluoride F-doping

乡村振兴背景下央企社会责任实践路径与新模式研究——华侨城1996—2021年纵向案例研究

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农业经济问题 2024年第1期 63-83页

作者：李世杰刘倩海南大学国际商学院海口570228

央企积极履行社会责任,是适应国际国内经济社会发展趋势的必然要求,也是深化国有企业改革、完善现代企业制度、提升企业可持续发展能力的路径选择。企业社会责任在实业界已得到高度关注并形成较多实践,但关于央企在乡村振兴背景下动态... 详细信息

央企积极履行社会责任,是适应国际国内经济社会发展趋势的必然要求,也是深化国有企业改革、完善现代企业制度、提升企业可持续发展能力的路径选择。企业社会责任在实业界已得到高度关注并形成较多实践,但关于央企在乡村振兴背景下动态践行社会责任的过程研究仍显不足。研究华侨城集团参与美丽乡村建设中践行社会责任案例过程发现,央企社会责任的成长过程是企业责任治理能力从低阶到高阶进阶,并最终基于责任内化型实践演变为敏捷治理运行机制的过程;央企社会责任实践模式分为聚焦经济增长使命的责任嵌入型模式、聚焦绿色双赢使命的责任学习型实践模式、聚焦人权保障使命的责任内化型实践模式,其运行机制包括社会责任融入机制、负责任研究与创新机制、敏捷治理机制;据此本文尝试构建央企社会责任实践路径及“APCC”机理模型,以期形成一般性理论逻辑框架。

关键词：企业社会责任国家战略责任内化敏捷治理机制

重庆官栈河大桥主桥主墩基础锁口钢管桩围堰加固

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桥梁建设 2024年第1期54卷 148-154页

作者：钱骥荚瑞馨宋世杰杨纪鹏重庆交通大学土木工程学院重庆400074 重庆交通大学山区桥梁与隧道工程国家重点实验室重庆400074

重庆官栈河大桥主桥为(62+110+62)m三跨连续刚构桥,主墩基础采用锁口钢管桩围堰施工。围堰施工正常水位+325.300 m,施工期控制水位+330.500 m。在该桥主墩围堰完成四周锁口钢管桩插打及前4道内支撑安装后,因极端天气原因,长寿湖水位上涨... 详细信息

重庆官栈河大桥主桥为(62+110+62)m三跨连续刚构桥,主墩基础采用锁口钢管桩围堰施工。围堰施工正常水位+325.300 m,施工期控制水位+330.500 m。在该桥主墩围堰完成四周锁口钢管桩插打及前4道内支撑安装后,因极端天气原因,长寿湖水位上涨到+332.200 m,危及围堰安全。为解决钢管桩围堰的安全问题,提出采用水下施工内支撑的加固方案。待围堰内部水头与外部保持一致后,将已经插打的锁口钢管桩加高至标高+334.000 m,拆除已安装好的4道内支撑,重新安装6道内支撑。采用MIDAS Civil软件分别建立加固前、后钢管桩围堰结构有限元模型,分析钢管桩及内支撑的受力安全与稳定性。结果表明:施工控制水位+330.500 m下,围堰结构最大正应力由加固前的162.6 MPa下降到加固后的82.3 MPa,下降了49.3%;承载水位可从施工控制水位+330.500 m增加到目标控制水位+333.500 m,且强度和刚度等均留有一定储备。水下施工内支撑的加固方案可提升围堰的承载能力。该桥围堰加固后整体受力效果良好,已顺利完成承台浇筑施工。

关键词：刚构桥锁口钢管桩围堰加固有限元法桥梁施工

PEEK填充PTFE摩擦学性能的分子动力学模拟分析

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润滑与密封 2024年第8期49卷 44-49页

作者：王妍汤赫男赵晶王世杰张潜沈阳工业大学机械工程学院辽宁沈阳110870

采用分子动力学的模拟研究方法,建立不同质量比的聚醚醚酮(PEEK)填充聚四氟乙烯(PTFE)复合材料的无定型模型(PEEK质量分数分别为5%、10%、15%、20%),对模型进行几何优化和动力学优化,并构建PEEK/PTFE复合材料与Fe摩擦副对摩模型。模拟... 详细信息

采用分子动力学的模拟研究方法,建立不同质量比的聚醚醚酮(PEEK)填充聚四氟乙烯(PTFE)复合材料的无定型模型(PEEK质量分数分别为5%、10%、15%、20%),对模型进行几何优化和动力学优化,并构建PEEK/PTFE复合材料与Fe摩擦副对摩模型。模拟分析结果显示:质量分数10%PEEK填充的PEEK/PTFE复合材料的耐磨特性最佳,其磨损率与PTFE材料相比降低了26.44%,且减摩特性保持良好。通过分析摩擦界面处的结合能可以得出,在纯PTFE基材中加入PEEK可有效降低摩擦界面处的结合能,降低PTFE与对偶面的相互作用,从而降低磨损。通过分析摩擦界面处的原子含量、径向分布函数以及自由体积分数可以得出,质量分数为10%的PEEK/PTFE复合材料的PEEK和PTFE分子链分布更加均匀;然而PEEK质量分数过高时,晶胞内易出现不均匀变形和应力集中现象,使得PTFE分子在摩擦过程中更易出现脱落现象,耐磨性降低。研究结果从原子尺度揭示了PEEK对PTFE材料摩擦学性能的作用机制,从微观视域揭示了PEEK填充PTFE的增强机制,为研发新型PTFE基复合材料提供理论参考。

关键词：聚四氟乙烯聚醚醚酮分子动力学复合材料摩擦学性能

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基于共轭共聚物网络的动态褶皱的多重调控

Science China Materials 2024年第1期67卷 363-371页

作者：钱杰章露枝王泽鸿吴诗杰姜学松林绍梁姚远 Frontiers Science Center for Materiobiology and Dynamic Chemistry of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China School of Chemistry&Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

环境刺激响应的动态微/纳米图案可调节表面特性,为智能表面的按需制备提供了有效的解决方案.我们合成了一种光响应共轭聚合物(P(AEG-AAzo-AAN)),基于简单的策略构建了光驱动的双层动态褶皱图案系统.聚合物所含蒽侧基的光二聚和偶氮苯侧... 详细信息

环境刺激响应的动态微/纳米图案可调节表面特性,为智能表面的按需制备提供了有效的解决方案.我们合成了一种光响应共轭聚合物(P(AEG-AAzo-AAN)),基于简单的策略构建了光驱动的双层动态褶皱图案系统.聚合物所含蒽侧基的光二聚和偶氮苯侧基的光异构化可以分别调节交联密度和应力松弛,从而决定褶皱的产生/擦除,实现多级次褶皱的按需制备.硫酸掺杂后,褶皱图案能够对湿度做出响应,薄膜变为半导体.这种多重响应动态褶皱可能在智能显示器和防伪标签中获得潜在的应用.

关键词：防伪标签共轭聚合物光驱动光异构化多重响应应力松弛交联密度策略构建

二维石墨烯/橡胶复合材料的力学和摩擦学研究进展

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化工新型材料 2024年第2期52卷 271-276页

作者：李欣昊王世杰钱程赵晶宋淑媛沈阳工业大学机械工程学院沈阳110870 辽宁石油化工大学机械工程学院抚顺113001

在石油开采行业中,橡胶用量遥遥领先于其他产品,但纯橡胶材料的力学、摩擦学性能不足以满足当前的实际需求。因此,需对橡胶进行补强处理,来提高其使用性能。氧化石墨烯(GO)因具有较高比表面积、且官能团丰富等特点,常作为补强填料掺入... 详细信息

在石油开采行业中,橡胶用量遥遥领先于其他产品,但纯橡胶材料的力学、摩擦学性能不足以满足当前的实际需求。因此,需对橡胶进行补强处理,来提高其使用性能。氧化石墨烯(GO)因具有较高比表面积、且官能团丰富等特点,常作为补强填料掺入橡胶基体中。由于GO之间的强范德华力和π-π键堆积,使其极易在橡胶基体中出现“团聚”现象。因此需对GO进行改性处理提高其分散性。系统地综述了GO、改性GO对橡胶复合材料力学、摩擦学等性能的影响,并概述了其在橡胶基体中的补强机理。最后,对该研究领域存在的一些基本问题提供了解决思路,并对GO/橡胶复合材料的发展进行展望。

关键词：氧化石墨烯改性橡胶分散复合材料