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Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

DEFENCE TECHNOLOGY 2024年第9期39卷 23-41页

作者： Zhao, Ziqi Li, Tong Sheng, Donglin Chen, Jian yan, amin Chen, yan Wang, Haiying Chen, Xiaowei Dai, Lanhong Chinese Acad Sci Inst Mech State Key Lab Nonlinear Mech Beijing 100190 Peoples R China Univ Chinese Acad Sci Sch Future Technol Beijing 100049 Peoples R China Univ Chinese Acad Sci Sch Engn Sci Beijing 100049 Peoples R China Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China

Shaped charge liner (SCL) has been extensively applied in oil recovery and defense industries. Achieving superior penetration capability through optimizing SCL structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse, high-speed jet stretching, and penetration. This study introduces an innovative optimization strategy for SCL structures that employs jet penetration efficiency as the primary objective function. The strategy combines experimentally validated finite element method with machine learning (FEM-ML). We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine learning. This index effectively evaluates the jet penetration performance. Furthermore, a multi-model fusion based on a machine learning optimization method, called XGBOOST-MFO, is put forward to optimize SCL structure over a large input space. The strategy's feasibility is demonstrated through the optimization of copper SCL implemented via the FEM-ML strategy. Finally, this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper liners. Therefore, the strategy can provide helpful guidance for the engineering design of SCL. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license.

关键词： Jet penetration efficiency Shaped charge liner FEM-ML XGBOOST MFO High-entropy alloy LONG ROD PERFORMANCE COMPRESSIBILITY EXTENSION SEARCH DESIGN MODEL

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Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

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Defence Technology 2024年第09期 23-41页

作者： Ziqi Zhao Tong Li Donglin Sheng Jian Chen amin yan yan Chen Haiying Wang Xiaowei Chen Lanhong Dai State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences School of Future Technology University of Chinese Academy of Sciences School of Engineering Science University of Chinese Academy of Sciences State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Shaped charge liner(SCL) has been extensively applied in oil recovery and defense industries. Achieving superior penetration capability through optimizing SCL structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse, high-speed jet stretching,and penetration. This study introduces an innovative optimization strategy for SCL structures that employs jet penetration efficiency as the primary objective function. The strategy combines experimentally validated finite element method with machine learning(FEM-ML). We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine learning. This index effectively evaluates the jet penetration performance. Furthermore, a multi-model fusion based on a machine learning optimization method, called XGBOOST-MFO, is put forward to optimize SCL structure over a large input space. The strategy's feasibility is demonstrated through the optimization of copper SCL implemented via the FEM-ML strategy. Finally, this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper liners. Therefore, the strategy can provide helpful guidance for the engineering design of SCL.

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Comparative Transcriptomic Analysis of Two Tomato Cultivars with Different Shelf-Life Traits

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 2075-2093页

作者： Abdul Karim amin yan He Xianglong Wang Pengwei Li Muhammad Ahmad Hassan Mohammad Yousof Soltani Yiling Zhang Mohammad Alem amin Ahmad Shah Ahmadzai Yajing Liu Songhu Wang Anhui Province Key Laboratory of Horticultural Crop Quality Biology School of HorticultureAnhui Agricultural UniversityHefei230036China Anhui Academy of Agricultural Sciences Hefei230001China Anhui Province Key Laboratory of Soybean Molecular Breeding and Crop Quality Biology School of AgronomyAnhui Agricultural UniversityHefei230036China Department of Horticulture Ghazni UniversityGhazni2301Afghanistan State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing210095China

Tomato(Solanum lycopersicum)is a perishable fruit because of its fast water loss and susceptibility to pathogens in the post-harvest stage,which leads to huge economic losses every *** this study,firstly from 19 tomato cultivars,we screened out two cultivars,Riogrand and SalarF1,having long and short shelf-life spans,***,shelf-life analysis was carried out for both cultivars at room *** exhibited that Riogrand showed higher firmness and less weight loss than *** ethylene production was higher in SalarF1,compared with Riogrand during post-harvest *** performed transcriptomic analysis of both cultivars in different storage *** discovered 2913,2188,and 11,119 differentially expressed genes(DEGs)for three post-harvest stages(0,20,and 40 Days Post-Harvest(DPH)),*** genes are enriched in ethylene biosynthesis and response,as well as cell wall-related *** response factor(ERF)ERF2 and ERF4 were highly expressed in SalarF1 with a short shelf life in 40 DPH,and the ethylene biosynthetic genes ACO1,ACO4,ACS6,and ACS2 were significantly upregulated in *** cell wall loosening and cell wall-related genes XTH3,XTH7,XTH23,1,3;1,4-β-D-Gluc-like,pGlcT1,Cellulase,PGH1,PL5,PL-like 1,PL-like 2 exhibited the highest levels of significance,being notably upregulated in the last stage of *** quantitative real-time polymerase chain reaction(qRT-PCR)analysis validated these gene expressions,which is in line with the transcriptome *** findings suggested that the extension of tomato fruit shelf life is mostly dependent on ethylene biosynthesis,signaling pathway genes,cell wall loosening,and cell wall-associated genes.

关键词： Shelf life transcriptome analysis tomato differentially expressed genes(DEGs) ethylene

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Regulating microstructure and composition by carbonizing in-situ grown metal-organic frameworks on cotton fabrics for boosting electromagnetic wave absorption

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Nano Research 2024年第8期17卷 7290-7300页

作者： Jie Jin Hongsen Long Hu Liu yan Guo Tiantian Bai Ben Bin Xu Mohammed A.amin Hua Qiu Mohamed H.Helal Chuntai Liu Changyu Shen Zeinhom M.El-Bahy Zhanhu Guo State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410000China School of Electronic Engineering North China University of Water Resources and Electric PowerZhengzhou 450046China Complex Conditions of High-end Tire Technology Innovation Center Shuguang Rubber Industry Research&Design Institute Co.LtdGuilin 541004China Integrated Composites Lab Department of Mechanical and Civil EngineeringNorthumbria UniversityNewcastle Upon TyneNE18STUK Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Chemistry Faculty of Arts and ScienceNorthern Border UniversityRafha 73213Saudi Arabia Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr City 11884CairoEgypt

High-temperature carbonized metal-organic frameworks(MOFs)derivatives have demonstrated their superiority for promising electromagnetic wave(EMW)absorbers,but they still suffer from limited EMW absorption capacity and narrow *** the advantage of microstructure and chemical composition regulation for the design of EMW absorber,hierarchical heterostructured MoS_(2)/CoS_(2)-Co_(3)O_(4)@cabonized cotton fabric(CF)(MCC@CCF)is prepared by growing ZIF-67 MOFs onto CF surface,chemical etching,and *** from the dual loss mechanism of magnetic-dielectric multicomponent carbonized MOFs,chemical etching and carbonization process can effectively introduce abundant micro-gap structure that can result in better impedance matching and stronger absorption capacity via internal reflection,doped heteroatoms(Mo,N,S)to supply additional dipolar polarization loss,and numerous heterointerfaces among MoS_(2),CoS_(2),Co_(3)O_(4),and CCF that produce promoted conduction loss and interfacial polarization ***,a minimal reflection loss of−52.87 dB and a broadest effective absorption bandwidth of 6.88 GHz were achieved via tunning the sample thickness and filler loading,showing excellent EMW absorption *** research is of great value for guiding the research on MOFs derivatives based EMW absorbing materials.

关键词： metal-organic frameworks hierarchical structure chemical etching sulfurization electromagnetic wave absorption

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增材制造Ti6Al4V钛合金的激波压缩状态方程与动态变形机理研究

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力学学报 2023年第8期55卷 1673-1685页

作者：牛洋洋李统周文博盛冬林鄢阿敏曹富华陈艳汪海英戴兰宏中国科学院力学研究所非线性力学国家重点实验室北京100190 中国科学院大学工程科学学院北京100049

增材制造工艺具有快速成型、结构可控等优势,有广阔的应用前景,然而增材制造的合金材料的动态性能研究相对贫乏.文章针对在国防空天领域应用广泛的Ti6Al4V合金,选取增材制造与锻造Ti6Al4V钛合金为研究对象,利用一级轻气炮系统,对两种不... 详细信息

增材制造工艺具有快速成型、结构可控等优势,有广阔的应用前景,然而增材制造的合金材料的动态性能研究相对贫乏.文章针对在国防空天领域应用广泛的Ti6Al4V合金,选取增材制造与锻造Ti6Al4V钛合金为研究对象,利用一级轻气炮系统,对两种不同工艺的钛合金材料开展不同冲击速度的平板撞击实验,同时借助光子多普勒测速(PDV)系统与阻抗匹配技术获得自由表面的粒子速度和激波速度,进而得到两种钛合金的Hugoniot状态方程.进一步,对变形样品微结构开展透射电镜(TEM)和电子背散射衍射(EBSD)表征,揭示其动态变形机理.发现两种合金都具有很高的相变阈值(锻造合金>7.90 GPa,增材制造合金>7.87 GPa)与冲击弹性极限HEL(锻造合金为2.56 GPa,增材制造合金为2.78 GPa),两种Ti6Al4V合金的塑性变形机理均为位错滑移主控,锻造合金在变形后期产生滑移带,增材制造合金的片层状α相与β相的相界面起着阻碍位错运动的强化作用,在变形后期位错线从α相中越过相界面滑移至相邻的另一个α相中,位错滑移越过相界面需要较大的应力输入,因此表现出相比锻造合金更高的冲击弹性极限HEL.

关键词：增材制造 Ti6Al4V合金冲击压缩 Hugoniot状态方程变形机理

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非围产期成人单核细胞性李斯特菌感染者25例的临床特征分析

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中华传染病杂志 2024年第2期42卷 84-90页

作者：许文李阿敏李璟成艳张野空军军医大学第二附属医院(第四军医大学唐都医院)疾病预防控制科西安710038 空军军医大学第二附属医院(第四军医大学唐都医院)传染病科西安710038

目的探讨非围产期成人单核细胞性李斯特菌(LM)感染者的临床特征。方法纳入2010年1月至2023年7月第四军医大学唐都医院收治的经病原学确诊的25例非围产期李斯特菌病患者,回顾性分析患者人口学资料、基础疾病、临床表现、实验室检查指标... 详细信息

目的探讨非围产期成人单核细胞性李斯特菌(LM)感染者的临床特征。方法纳入2010年1月至2023年7月第四军医大学唐都医院收治的经病原学确诊的25例非围产期李斯特菌病患者,回顾性分析患者人口学资料、基础疾病、临床表现、实验室检查指标、头颅影像学表现、抗感染治疗方案、临床转归等特征。分别比较李斯特菌败血症组和李斯特菌性脑膜脑炎组、康复组和死亡组患者的临床特征。统计学分析采用独立样本t检验和曼-惠特尼U检验。结果25例患者年龄为(52.84±12.17)岁,男18例,女7例,主要临床表现为发热[23/25(92%)]、头痛[15/25(60%)]、意识障碍[12/25(48%)]、呕吐[8/25(32%)],13例(52%)患者存在基础疾病(包括血液系统疾病、自身免疫病、实体肿瘤、肝硬化等)。李斯特菌败血症组和李斯特菌性脑膜脑炎组在血常规、转氨酶、蛋白质水平、肾功能、电解质、血糖、炎症指标之间的差异均无统计学意义(均P>0.05)。死亡组血小板计数高于康复组,差异有统计学意义[(243.10±92.96)×10^(9)/L比(157.80±75.55)×10^(9)/L,t=2.45,P=0.022],但康复组和死亡组在生物化学、炎症指标之间的差异均无统计学意义(均P>0.05)。李斯特菌性脑膜脑炎患者头颅影像学检查表现为颅内感染、脑水肿/脑积水或脑疝。19例李斯特菌性脑膜脑炎患者的脑脊液压力[220.0(130.0,290.0)mmH_(2)O(1 mmH_(2)O=0.0098 kPa)]、脑脊液细胞总数[522.0(350.0,783.0)×10^(6)/L]、脑脊液白细胞数[356.0(266.0,668.0)×10^(6)/L]和脑脊液蛋白质定量[1817.0(822.5,6000.0)mg/L]均升高,15例患者脑脊液氯化物降低[(111.70±8.51)mmol/L],10例患者脑脊液葡萄糖水平降低[3.71(1.45,7.11)mmol/L]。血培养和脑脊液培养药物敏感试验结果示LM对氨苄西林均敏感,分别有1例、3例、3例患者对青霉素、美罗培南、复方磺胺甲噁唑耐药。17例康复患者中13例使用基于氨苄西林或青霉素等敏感抗菌药物的治疗方案。结论罹患基础疾病、免疫功能低下的患者出现高热、中枢神经系统感染等临床症状时,应警惕李斯特菌病可能,早期应用以氨苄西林为基础的治疗方案有利于患者临床康复。

关键词：单核细胞增生利斯特菌中枢神经系统感染败血症临床特征

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基于薄层单元模型的弹体与引信系统螺纹连接参数确定方法

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兵工学报 2021年第4期42卷 743-754页

作者：鄢阿敏皮爱国王健黄风雷王晓锋北京理工大学爆炸科学与技术国家重点实验室北京100081 北京系统工程研究所北京100034

螺纹连接是侵彻弹体与引信体连接的主要形式之一,直接影响着弹体与引信系统振动响应特性。针对现有数值仿真手段难以准确表征螺纹连接的问题,提出用薄层单元模拟螺纹连接的有效方案,结合理论与试验研究建立薄层单元材料参数的确定方法... 详细信息

螺纹连接是侵彻弹体与引信体连接的主要形式之一,直接影响着弹体与引信系统振动响应特性。针对现有数值仿真手段难以准确表征螺纹连接的问题,提出用薄层单元模拟螺纹连接的有效方案,结合理论与试验研究建立薄层单元材料参数的确定方法。基于螺纹连接弹性模型与薄层单元理论推导出薄层单元的材料参数;将薄层单元材料参数传递到有限元模型中进行建模,通过螺纹管以及弹体与引信系统模态试验对薄层单元模型的计算结果进行验证。结果表明:与不同螺距及不同旋合长度螺纹管模态试验结果比较,薄层单元模型计算误差最大为5.11%;与节点融合建模方式比较,弹体与引信系统采用薄层单元建模方式进行计算后,前3阶模态频率最大误差从17.72%下降到2.54%.

关键词：弹体与引信系统螺纹连接模态试验薄层单元弹性模型动态响应分析

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Photothermally Enhanced Dual Enzyme-mimic Activity of Gold-Palladium Hybrid Nanozyme for Cancer Therapy

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Chinese Journal of Chemistry 2023年第23期41卷 3189-3196页

作者： yan Kang Chao Li Huali Shi amin Zhang Chusen Huang Chaohui Zhou Nengqin Jia The Education Ministry Key Lab of Resource Chemistry Joint International Research Laboratory of Resource ChemistryShanghai Key Laboratory of Rare Earth Functional MaterialsCollege of Chemistry and Materials ScienceShanghai Normal University100 Guilin RDShanghai200234 China Institute of Nano Biomedicine and Engineering Shanghai Engineering Research Center for Intelligent Diagnosis and Treatment InstrumentDepartment of Instrument Science and EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong University800 Dongchuan RDShanghai200240 China

Based on characteristics of the tumor microenvironment(TME),including acidity,hypoxia,inflammation and hydrogen peroxide overload,combined with emerging nanotechnologies,designing nanoplatforms with TME specificity/responsiveness for tumor treatment is a promising nanotherapeutic *** this work,a multifunctional gold-palladium bimetallic cascade nanozyme was constructed for effective photothermal-enhanced cascade catalyzed synergistic therapy of *** dumbbell-like Au-Pd bimetallic nanomaterial(Au NRs-Pd@HA)was obtained by reducing palladium on gold nanorods with ascorbic acid(AA)and further modified with hyaluronic acid(HA).The introduction of HA brings biocompatibility and targeting *** zebrafish embryos model showed that Au NRs-Pd@HA had good biocompatibility and low *** NRs-Pd@HA can induce catalytic conversion of glucose to generate H_(2)O_(2) efficiently,and subsequently undergo cascade reaction to produce abundant·OH radicals,exhibiting peroxidase-like(POD-like)and glucose oxidase-like(GOD-like)*** generated·OH was a key factor for tumor ***,Au NRs-Pd@HA exhibits good photothermal performance under 808 nm irradiation,in favor of photothermal therapy(PTT).Especially,the POD-like and GOD-like activities were significantly enhanced due to the photothermal *** synergistic PTT and photothermal-enhanced nanozymes with cascade catalytic effect enabled efficient and safe cancer therapy.

关键词： Nanozymes catalyzed therapy Photothermal therapy Cascade catalytic Good biocompatibility Cancer Antitumor agents Catalytic therapy

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How Challenge Stress Affects Mental Health among College Students during the COVID-19 Pandemic: The Moderating Role of Self-Efficacy

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International Journal of Mental Health Promotion 2021年第2期23卷 167-175页

作者： yan Zeng Shaoping Qiu amin Alizadeh Tiefang Liu The School of Literature and Communication Guangdong Polytechnic Normal UniversityGuangzhou510665China The Department of Engineering Technology&Industrial Distribution Texas A&M UniversityCollege Station77843USA The Department of Educational Administration&Human Resource Development Texas A&M UniversityCollege Station77843USA The School of Educational Science Hunan Normal UniversityChangsha410081China

While a plethora of studies has been conducted to examine stress and its impact on mental health in western countries,research is scarce investigating the relationship between student challenge stress and health illness in the context of Chinese *** studies examined the moderating effect of self-efficacy on the relationship between challenge stress and health *** study attempted to investigate the relationships between these three variables among Chinese college ***,this study focused on examining whether self-efficacy moderated the effect of perceived challenge stress on students’mental ***,the differences were tested between male and female students in terms of these three variables.A sample of 578 Chinese college students was recruited over an approximately 12-week period from 7 Chinese *** online survey link was dis-tributed through *** SPSS version 26 software was used to analyze the *** showed that there is no significant difference between genders in terms of perceived challenge stress,self-efficacy,and students’mental *** addition,challenge stress was positively related to the students’mental health(β=0.35,p<0.01)while there was a negative association between self-efficacy and mental health(β=-0.41,p<0.01).Furthermore,self-efficacy plays a moderating role in the relationship between challenge stress and mental health(β=-0.11,p=0.02).Students with low self-efficacy tend to experience more mental health *** is suggested that Chinese colleges and universities pay more attention to students with low self-efficacy,either through faculty/staff interven-tions or peer *** consider reducing students’academic stress to improve their mental health.

关键词： Challenge stress self-efficacy mental health college students

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月基甚低频射电干涉仪Tripole天线特性研究

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电波科学学报 2010年第6期25卷 1064-1072页

作者：陈林杰 amin aminaei 颜毅华中国科学院国家天文台北京100012 中国科学院太阳活动重点实验室(国家天文台) 北京100012 Radboud University Nijmegen

对月基甚低频射电干涉仪所用Tripole矢量有源天线进行理论分析,计算了不同激励下的辐射方向图以及给定方向图时所需的激励。不同于传统的天线阵列方法,单一的Tri-pole(三阵子)天线即可实现对入射波达波方向(DOA)的估计。运用改进的基于... 详细信息

对月基甚低频射电干涉仪所用Tripole矢量有源天线进行理论分析,计算了不同激励下的辐射方向图以及给定方向图时所需的激励。不同于传统的天线阵列方法,单一的Tri-pole(三阵子)天线即可实现对入射波达波方向(DOA)的估计。运用改进的基于单位矩阵束(UMP)和最小二乘法(LS)的算法实现了对Tripole天线达波方向的估计,该算法适用于对入射波不同频率分量的DOA估计,计算量小,且估计精度更高,仿真结果表明了算法的有效性。

关键词：射电干涉仪 Tripole天线 DOA估计

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