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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

基于数字图像相关原理的埋头弹程序燃烧特性试验研究

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兵工学报 2024年第4期45卷 1047-1059页

作者：师军飞钱林方陈光宋尹强刘道坤李仲刚南京理工大学机械工程学院江苏南京210094 西北机电工程研究所陕西咸阳712099 北方工具有限公司黑龙江牡丹江157000

为分析埋头弹的装药程序燃烧特性和上膛挤进运动特性,对埋头弹两级点火发射过程进行试验研究。设计并建立程序燃烧特性试验系统,采用高速摄像系统获得各组弹丸的运动图像序列。基于数字图像相关原理,对各组图像序列进行定性和定量分析,... 详细信息

为分析埋头弹的装药程序燃烧特性和上膛挤进运动特性,对埋头弹两级点火发射过程进行试验研究。设计并建立程序燃烧特性试验系统,采用高速摄像系统获得各组弹丸的运动图像序列。基于数字图像相关原理,对各组图像序列进行定性和定量分析,对回收的弹带刻槽形貌分析测量,获得一级点火的弹丸运动特性,两级点火的程序燃烧特性以及弹带刻槽形貌特性。研究结果表明:速燃点火药的质量直接影响一级点火弹丸上膛性能,质量增加时弹丸上膛时间显著缩短,上膛速度大幅提高;可燃导向筒过早的破碎会导致上膛速度大幅增加,使弹带刻槽形貌非常恶劣,不能可靠密封弹后火药燃气和可靠导转弹丸运动,影响内弹道性能和弹丸的膛内运动姿态;需要对速燃点火药与可燃导向筒进行合理的匹配设计,保证可燃导向筒的破碎时机处于可控范围,从而实现理想的两级点火和程序燃烧设计目标。

关键词：埋头弹数字图像相关原理两级点火程序燃烧可燃导向筒上膛速度弹带刻槽

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Modification of CaO-based sorbents prepared from calcium acetate for CO_2 capture at high temperature

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Chinese Journal of Chemical Engineering 2017年第5期25卷 572-580页

作者： Xiaotong Liu junfei shi Liu He Xiaoxun Ma shisen Xu School of Chemical Engineering Northwest University Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energy Shaanxi Research Center of Engineering Technology for Clean Coal Conversion China Huaneng Group Clean Energy Technology Research Institute

CaO-based sorbent is considered to be a promising candidate for capturing CO_2 at high temperature. However,the adsorption capacity of CaO decreases sharply with the increase of the carbonation/calcination cycles. In this study, CaO was derived from calcium acetate(CaAc_2), which was doped with different elements(Mg, Al,Ce, Zr and La) to improve the cyclic stability. The carbonation conversion and cyclic stability of sorbents were tested by thermogravimetric analyzer(TGA). The sorbents were characterized by N_2 isothermal adsorption measurements, scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the cyclic stabilities of all modified sorbents were improved by doping elements, while the carbonation conversions of sorbents in the 1st cycle were not increased by doping different elements. After 22 cycles, the cyclic stabilities of CaO–Al, CaO–Ce and CaO–La were above 96.2%. After 110 cycles, the cyclic stability of CaO–Al was still as high as 87.1%. Furthermore, the carbonation conversion was closely related to the critical time and specific surface area.

关键词： CO2 capture CaO-based sorbent Carbonation conversion Cyclic stability Critical time Mesoporous structure

High-dimensional uncertainty quantifi cation of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method

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海上平台电解式生活污水处理装置生化适应性改造

Defence technology 2024年第2期

作者： Mingming Wang Linfang Qian Guangsong Chen Tong Lin junfei shi shijie Zhou

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化工设计通讯 2024年第1期50卷 136-138页

作者：石俊飞国健于文轩王丹中海油天津化工研究设计院有限公司天津300382

分析了某海上平台电解式生活污水处理装置存在的问题,通过工艺计算,将原有罐体作为生化功能罐,同时增加MBR处理单元,通过投加活性污泥及耐盐菌种,并经过培养驯化,设备COD去除率从58%提升至80%,出水COD稳定在125mg/L左右,有效解决了原设... 详细信息

分析了某海上平台电解式生活污水处理装置存在的问题,通过工艺计算,将原有罐体作为生化功能罐,同时增加MBR处理单元,通过投加活性污泥及耐盐菌种,并经过培养驯化,设备COD去除率从58%提升至80%,出水COD稳定在125mg/L左右,有效解决了原设备污染物去除效率低、设备运行不稳定的问题,消除了老旧设备存在的环保隐患。

关键词：电解式生活污水处理装置适应性改造 MBR

ANALYSIS OF LIQUEFACTION HAZARD DUE TO EARTHQUAKE

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ANALYSIS OF LIQUEFACTION HAZARD DUE TO EARTHQUAKE

High-speed GaN-based laser diode with modulation bandwidth exceeding 5 GHz for 20 Gbps visible light communication

中日双边软弱地基处理学术研讨会

作者： XIE junfei shi Zhaoji(Institute of Engineering Mechanics SSB China)

＜正＞The aim of this work is to establish a quantitative analysis approach of liquefaction hazard. Based on the microscopic field data of lique faction it is pointed out that non-uniform settlement of building is the primary type of damages caused by sand liquefcation during earthquake. Then a computation algorithem for evaluating settlements is programmed on the basis of "softening model" idea, and 33 liquefac tion settlement events are evaluated by use of this test-computation approach. The results of these evaluation are in good agreement with the observed ones.

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来源： cnki会议评论

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Photonics Research 2024年第6期12卷 1186-1193页

作者： junfei WANG JUNHUI HU CHAOWEN GUAN YUQI HOU ZENGYI XU LEIHAO SUN YUE WANG YUNING ZHOU BOON S.OOI JIANYANG shi ZIWEI LI JUNWEN ZHANG NAN CHI SHAOHUA YU CHAO SHEN School of Information Science and Technology Fudan UniversityShanghai 200433China Peng Cheng Laboratory Shenzhen 518000China ZGC Institute of Ubiquitous-X Innovation and Applications Beijing 100876China Photonics Laboratory King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Visible light communication(VLC)based on laser diodes demonstrates great potential for high data rate maritime,terrestrial,and aerial wireless data ***,we design and fabricate high-speed blue laser diodes(LDs)grown on c-plane gallium nitride(GaN)*** was achieved through active region design and miniaturization toward a narrow ridge waveguide,short cavity length,and single longitudinal mode Fabry–Perot laser *** fabricated mini-LD has a low threshold current of 31 mA and slope efficiency of 1.02 W/A.A record modulation bandwidth of 5.9 GHz(−3dB)was measured from the *** the developed mini-LD as a transmitter,the VLC link exhibits a high data transmission rate of 20.06 Gbps adopting the bit and power loading discrete multitone(DMT)modulation *** corresponding bit error rate is 0.003,satisfying the forward error correction *** demonstrated GaN-based mini-LD has significantly enhanced data transmission rates,paving the path for energy-efficient VLC systems and integrated photonics in the visible regime.

关键词： communication diode waveguide

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采用联合相似度谱聚类集成的极化SAR分类

西安电子科技大学学报 2015年第3期42卷 48-53,128页

作者：刘璐王蓉芳焦李成石俊飞西安电子科技大学智能感知与图像理解教育部重点实验室陕西西安710071

为了降低谱聚类算法尺度参数对分类结果的影响,避免Nystrm逼近导致的分类结果不稳定,提出了一种基于谱聚类集成的极化合成孔径雷达(SAR)地物分类方法.首先,利用像素间的空间关系和极化信息,将基于相干矩阵Wishart距离的相似性测度和... 详细信息

为了降低谱聚类算法尺度参数对分类结果的影响,避免Nystrm逼近导致的分类结果不稳定,提出了一种基于谱聚类集成的极化合成孔径雷达(SAR)地物分类方法.首先,利用像素间的空间关系和极化信息,将基于相干矩阵Wishart距离的相似性测度和基于极化特征矢量欧氏距离的相似性测度相结合,引入马尔可夫随机场势函数,构造谱聚类的相似性矩阵;然后,采用基于Nystrm逼近的谱聚类实现极化SAR数据的单次谱分类;最后,采用集成策略完成对极化SAR图像的地物分类.实验结果表明,该算法提高了分类精度,区域一致性保持较好,且分类结果稳定.

关键词：极化合成孔径雷达谱聚类集成 Wishart距离马尔可夫随机场

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埋头弹高速冲击挤进入膛特性研究

兵工学报 2023年第3期44卷 656-669页

作者：师军飞钱林方陈红彬付佳维南京理工大学机械工程学院江苏南京210094 西北机电工程研究所陕西咸阳712099

为研究埋头弹高速冲击挤进入膛过程的力学机理和运动规律,将某40 mm口径埋头弹火炮作为对象,分析建立其内弹道过程的数理模型,并通过实弹射击试验验证内弹道模型的准确性。考虑界面间的摩擦和接触特性,采用FEM-SPH耦合算法建立了高速冲... 详细信息

为研究埋头弹高速冲击挤进入膛过程的力学机理和运动规律,将某40 mm口径埋头弹火炮作为对象,分析建立其内弹道过程的数理模型,并通过实弹射击试验验证内弹道模型的准确性。考虑界面间的摩擦和接触特性,采用FEM-SPH耦合算法建立了高速冲击挤进模型,将内弹道数值解作为边界条件,通过数值计算得到弹带变形、弹丸运动、弹丸姿态和挤进阻力等变化规律。研究结果表明:所建立的弹道模型准确合理,弹丸的初始上膛速度为78.2 m/s;整个挤进过程分为减速挤进和加速挤进阶段,两阶段之间弹丸处于准静止状态,减速挤进过程中弹丸姿态发生周期性的变化,摆动角幅值不断下降,加速挤进过程,摆动角迅速增大,随着挤进完成摆动角呈现出减小的趋势,完成挤进用时2.65 ms,完成挤进时弹丸速度为73.92 m/s;挤进过程弹带表面温度接近材料熔点;动态挤进阻力呈现两次“上升-下降”过程,最大挤进阻力为95.288 kN,完全挤进时阻力降低并稳定到10 kN。

关键词：埋头弹内弹道冲击挤进 FEM-SPH耦合算法弹丸姿态挤进阻力

维普期刊数据库博看期刊

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无钴超高强钢G50两种工艺路线的探讨

特钢技术 2006年第2期11卷 14-16页

作者：史骏飞攀钢集团四川长城特殊钢有限责任公司

就G50电极棒真空冶炼与EBT+LF+VOD精炼两种冶炼工艺的对比分析,着重对精炼工艺进行探讨,认为新工艺冶炼效果完全达到了技术要求与冶炼目的,该工艺在我厂完全可以实施。

关键词： G50 成分性能效益