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Resistance of grid steel-tube-confined concrete targets against projectile impact: Experimental investigation and analytical engineering model

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Defence Technology（防务技术） 2022年第9期18卷 1622-1642页

作者： dian-yi song Qing-hua Tan Chao-mei Meng yi-min Huang Yang-yueye Cao Zhi-gang Jiang Undergraduate School National University of Defense TechnologyChangsha410072PR China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073PR China College of Aerospace Engineering Air Force Engineering UniversityXi'an710038PR China

Steel-tube-confined concrete(STCC) targets are provided with excellent anti-penetration performance over semi-infinite concrete(SIC) targets since the steel tube imposes passive restraint on the in-filled concrete during the penetration process. Grid STCC system with square steel tubes is a potential solution to protective structures. In this paper, experiments of 9-cell grid STCC targets penetrated by 12.7 mm Armor Piercing Projectile(APP) were performed. The influence of side length and thickness of steel tube,steel ratio and impact velocity on anti-penetration performance were taken into account. Additionally,single-cell square STCC targets were also designed and tested for comparison with the 9-cell grid STCC targets. Damage modes and parameters of the tested targets were measured and discussed. Moreover,the stiffness of radial confinement of grid STCC targets is achieved according to the elastic solution of infinite cylindrical shell in Winkler medium. Furthermore, the penetration resistance and depth of penetration(DOP) for grid STCC targets are obtained on the basis of the dynamic finite spherical cavityexpansion(FSCE) models including radial confinement effect. It is shown that the 9-cell grid STCC targets with optimal dimension match of thickness and side length of steel tube can reduce the DOP by about17 % and 23 % in comparison with the SIC targets and single-cell square STCC targets, respectively, due to both the confinement of square steel tube to concrete in the impacted cell and the additional confinement of the surrounding cells to the impacted cell;the penetration resistance and DOP of the grid and cellular STCC targets with similar steel ratio is close, and thus the grid STCC targets with simpler manufacturing process and excellent in-plane expandability are preferred in engineering practice;moreover, the predicted results of DOP model based on the FSCE models agree well with the tested results with the maximum disparity less than 12 % and the prop

关键词： Penetration mechanics Grid structural system Steel-tube-confined concrete(STCC)targets Armor piercing projectile(APP) Depth of penetration(DOP) Finite spherical cavity expansion(FSCE)

Analytical solutions for finite cylindrical dynamic cavity expansion in compressible elastic-plastic materials

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Applied Mathematics and Mechanics(English Edition) 2014年第8期35卷 1039-1050页

作者：甄明蒋志刚宋殿义刘飞 College of Basic Education National University of Defense Technology

Analytical solutions for the dynamic cylindrical cavity expansion in a com-pressible elastic-plastic cylinder with a finite radius are developed by taking into account of the effect of lateral free boundary, which are different from the traditional cavity expan-sion models for targets with infinite dimensions. The finite cylindrical cavity expansion process begins with an elastic-plastic stage followed by a plastic stage. The elastic-plastic stage ends and the plastic stage starts when the plastic wave front reaches the lateral free boundary. Approximate solutions of radial stress on cavity wall are derived by using the Von-Mise yield criterion and Forrestal’s similarity transformation method. The effects of the lateral free boundary and finite radius on the radial stress on the cavity wall are discussed, and comparisons are also conducted with the finite cylindrical cavity expansion in incompressible elastic-plastic materials. Numerical results show that the lateral free boundary has significant influence on the cavity expansion process and the radial stress on the cavity wall of metal cylinder with a finite radius.

关键词： penetration cavity expansion metal target free boundary radial stress

基于改进QPSO的两轮移动机器人区间二型模糊逻辑控制

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控制与决策 2019年第2期34卷 261-268页

作者：佃松宜梁伟博赵涛四川大学电气信息学院成都610065

以两轮移动机器人(TWMR)为对象,针对机器人的非线性模型分别设计控制机器人平衡和位置的区间二型模糊逻辑控制器(IT2 FLC).针对区间二型模糊规则中参数难以设定的问题,通过改进的量子粒子群算法(LTQPSO)优化区间二型模糊集参数,并给出... 详细信息

以两轮移动机器人(TWMR)为对象,针对机器人的非线性模型分别设计控制机器人平衡和位置的区间二型模糊逻辑控制器(IT2 FLC).针对区间二型模糊规则中参数难以设定的问题,通过改进的量子粒子群算法(LTQPSO)优化区间二型模糊集参数,并给出优化算法的流程图.针对区间二型模糊逻辑控制器和一型模糊逻辑控制器(T1 FLC)对平衡和位置的控制效果进行对比.进一步考虑质量不确定和位置扰动对两种控制器控制效果的影响.仿真结果表明, IT2 FLC可以有效地达到设定的控制目标,与T1 FLC相比, IT2 FLC拥有更好的处理不确定性的能力以及更强的抗扰动能力.

关键词：区间二型模糊逻辑模糊集不确定性量子粒子群优化两轮移动机器人

多轴亚微米级平面定位台的滑模观测器无传感控制

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光学精密工程 2014年第11期22卷 3067-3073页

作者：佃松宜向国菲蒲明四川大学电气信息学院四川成都610065

针对Sawyer电机驱动的平面定位台的多轴精密定位问题(X、Y和θz轴),提出了一种新的部分无传感控制方法。用激光干涉仪检测定位台一个方向上的平移运动和摆动,并构建相应的闭环控制;同时,应用滑模观测器估计另一个方向上的平移运动并构... 详细信息

针对Sawyer电机驱动的平面定位台的多轴精密定位问题(X、Y和θz轴),提出了一种新的部分无传感控制方法。用激光干涉仪检测定位台一个方向上的平移运动和摆动,并构建相应的闭环控制;同时,应用滑模观测器估计另一个方向上的平移运动并构建对应轴的闭环控制。在此基础上,通过实验从开环控制、多轴全闭环控制及部分无传感控制三方面对比了定位性能。实验结果表明:采用部分无传感控制,多轴平面定位台的重复定位精度达到亚微米(0.25μm)级;部分无传感控制下的动子行程与开环控制相同(X轴300mm、Y轴300mm),远大于基于多轴位置传感的全闭环控制下的动子行程(X轴100mm、Y轴100mm);获得的结果可满足应用设计要求。

关键词：平面定位台滑模观测器无传感控制精密定位

When debugging encounters artificial intelligence: state of the art and open challenges

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Science China(Information Sciences) 2024年第4期67卷 42-84页

作者： yi song Xiaoyuan XIE Baowen XU School of Computer Science Wuhan University State Key Laboratory of Novel Software Technology Nanjing University

Both software debugging and artificial intelligence techniques are hot topics in the current field of software engineering. Debugging techniques, which comprise fault localization and program repair, are an important part of the software development lifecycle for ensuring the quality of software systems. As the scale and complexity of software systems grow, developers intend to improve the effectiveness and efficiency of software debugging via artificial intelligence(artificial intelligence for software debugging, AI4SD). On the other hand, many artificial intelligence models are being integrated into safety-critical areas such as autonomous driving, image recognition, and audio processing, where software debugging is highly necessary and urgent(software debugging for artificial intelligence, SD4AI). An AI-enhanced debugging technique could assist in debugging AI systems more effectively, and a more robust and reliable AI approach could further guarantee and support debugging techniques. Therefore, it is important to take AI4SD and SD4AI into consideration comprehensively. In this paper, we want to show readers the path, the trend, and the potential that these two directions interact with each other. We select and review a total of 165 papers in AI4SD and SD4AI for answering three research questions, and further analyze opportunities and challenges as well as suggest future directions of this cross-cutting area.

关键词： software debugging fault localization program repair artificial intelligence machine learning

Preparation and characterization of high-reactivity explosive-based nano-boron microspheres

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Particuology 2024年第10期93卷 125-136页

作者： Chen Dong yi Wang Kanghui Jia Dan song Xiaolan song Chongwei An School of Materials Science and Engineering North University of ChinaTaiyuan030051China Jinxi Group Shanxi Jiangyang Chemical Co. Ltd.Taiyuan030051China China Ordnance Institute of Science and Technology Beijing100089China School of Environment and Safety Engineering North University of ChinaTaiyuan030051China

Boron nanoparticles,with their remarkably high gravimetric and volumetric calorific values,emerge as the most promising fuel in energetic ***,challenges such as susceptibility to oxidation,high ignition temperature,and low combustion efficiency have constrained their further *** this study,we fabricated high explosives based nano-boron microspheres with uniform size using the electrostatic spray method,in which the boron nanoparticles and high explosives(CL-20 or PETN)are closely bonded together by fluorinated polymer(F2602)and evenly *** results indicated that the microspheres exhibited high sphericity and showed an enhanced antioxidant *** addition of high-energy explosives not only reduced the thermal oxidation temperature of nano-boron powder within the microspheres but also significantly enhanced the pressurization ***,the microspheres with added high-energy explosives released more energy during the combustion *** to physically mixed samples,electrostatically sprayed microspheres with a uniform microstructure still exhibited higher ***,the design and synthesis of microspheres with controllable structures using the electrostatic spray method show promising application prospects.

关键词： Nano-boron CL-20 PETN Electrospraying Ignition and combustion

Design,fabrication,and characterization of hierarchical mechanical metamaterials

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Frontiers of Mechanical Engineering 2024年第1期19卷 73-83页

作者： Jian song Junfei YAN Bengang yi Automotive Engineering Research Institute BYD Auto Industry Co.Ltd.Shenzhen 518000China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China

Natural mechanical materials,such as bamboo and bone,often exhibit superior specific mechanical properties due to their hierarchical porous *** the principle of hierarchy as inspiration can facilitate the development of hierarchical mechanical metamaterials(HMMs)across multiple length scales via 3D *** this work,we propose self-similar HMMs that combine octet-truss(OCT)architecture as the first and second orders,with cubic architecture as the third or more *** HMMs were fabricated using stereolithography 3D printing,with the length sizes ranging from approximately 200µm to the centimeter *** compressive stress–strain behaviors of HMMs exhibit a zigzag characteristic,and the toughness and energy absorption can be significantly enhanced by the hierarchical *** compressive moduli are comparable to that of natural materials,and the strengths are superior to that of most polymer/metal foams,alumina hollow/carbon lattices,and other natural ***,the flexural stress–strain curves exhibit a nonlinear behavior,which can be attributed to the hierarchical architecture and local damage *** relatively high mechanical properties can be attributed to the synergistic effect of the stretch-dominated OCT architecture and the bending-dominated cube ***,an ultralight HMM-integrated unmanned aerial vehicle(HMM-UAV)was successfully designed and *** HMM-UAV is~85%lighter than its bulk counterpart,remarkably extending the flight duration time(~53%).This work not only provides an effective design strategy for HMMs but also further expands the application benchmark of HMMs.

关键词： 3D printing mechanical metamaterials hierarchical architecture mechanical behavior unmanned aerial vehicle(UAV)

Honokiol Prevents Intestinal Barrier Dysfunction in Mice with Severe Acute Pancreatitis and Inhibits JAK/STAT1 Pathway and Acetylation of HMGB1

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Chinese Journal of Integrative Medicine 2024年第6期30卷 534-542页

作者： LI Jie CHEN Ya-feng GAO Lei LI yi-jie FENG dian-xu Department of General Surgery Putuo HospitalShanghai University of Traditional Chinese MedicineShanghai200062China

Objective To investigate the effect of honokiol(HON)and the role of high-mobility group protein B1(HMGB1)on the pathogenesis of severe acute pancreatitis(SAP).Methods Thirty mice were numbered according to weight,and randomly divided into 5 groups using a random number table,including control,SAP,SAP and normal saline(SAP+NS),SAP and ethyl pyruvate(SAP+EP),or SAP+HON groups,6 mice in each *** of pancreas,intestine,and blood were collected 12 h after SAP model induction for examination of pathologic changes,immune function alterations by enzyme linked immunosorbent assay(ELISA),and Western *** vitro experiments,macrophages were divided into 5 groups,the control,lipopolysaccharide(LPS),LPS+DMSO(DMSO),LPS+anti-HMGB1 monoclonal antibody(mAb),and LPS+HON *** tight connection level was determined by transmission electron microscopy and fluorescein *** location and acetylation of HMGB1 were measured by Western ***,pyridone 6 and silencing signal transducer and activator of the transcription 1(siSTAT1)combined with honokiol were added to determine whether the Janus kinase(JAK)/STAT1 participated in the regulation of honokiol on *** protein expression levels of HMGB1,JAK,and STAT1 were detected using Western *** Mice with SAP had inflammatory injury in the pancreas,bleeding of intestinal tissues,and cells with disrupted *** in the SAP+HON group had significantly fewer pathological *** with SAP also had significant increases in the serum levels of amylase,lipase,HMGB1,tumor necrosis factor-α,interleukin-6,diamine oxidase,endotoxin-1,and *** in the SAP+HON group did not show these abnormalities(P<0.01).Studies of Caco-2 cells indicated that LPS increased the levels of occludin and claudin-1 as well as tight junction permeability,decreased the levels of junctional adhesion molecule C,and elevated intercellular permeability(P<0.01).HON treatment blocked these *** of

关键词： severe acute pancreatitis intestinal barrier dysfunction honokiol high-mobility group protein B1 Januskinase signal transducerand activatorof transcription1

Effects of the urban landscape on heatwave-mortality associations in Hong Kong: comparison of different heatwave definitions

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 145-156页

作者： Jinglu song yi Lu Thomas Fischer Kejia Hu Department of Urban Planning and Design Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China Department of Architecture and Civil Engineering City University of Hong KongKowloon TongHong Kong 999077China Environmental Assessment and Management Research Centre School of Environmental SciencesUniversity of LiverpoolLiverpool L35TRUK Research Unit for Environmental Sciences and Management Faculty of Natural and Agricultural SciencesNorth West UniversityPotchefstroom 31750South Africa Institute of Big Data in Health Science School of Public HealthZhejiang UniversityZijingang CampusHangzhou 310058China

Despite increased attention given to potential modifiers of temperature-mortality associations, evidence for variations between different urban landscape characteristics remains limited. It is in this context that in this paper effect modifications of multiple urban landscape characteristics are explored under different heatwave definitions for different age groups and gender in Hong Kong, China. Daily meteorological data and heatwave-related mortality counts from 2008 to 2017 were collected from the Hong Kong Census and Statistics Department, China. A case-only design was adopted, combined with logistic regression models to examine the modification effects of five urban landscape characteristics under six heatwave definitions. Stratified analyses were conducted to investigate age- and gender-specific effect modifications. It is found that individuals living in greener areas experienced lower levels of mortality during or immediately after heatwaves. In contrast, a higher building density and nighttime land surface temperature (LST) were associated with a higher heatwave-related mortality risk. Pronounced effect modifications of these urban landscape characteristics were observed under hotter and longer heatwaves, and in older adults (age ≥ 65 years) and males. The findings provide a scientific basis for policymakers and practitioners when considering measures for coping with hotter, longer, and more frequent heatwaves in the context of global climate change.

关键词： Urban landscape Heatwave Mortality Effect modification Intra-urban differences Health risk reduction