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Bidirectional parallel multi-branch convolution feature pyramid network for target detection in aerial images of swarm UAVs

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Defence Technology（防务技术） 2021年第4期17卷 1531-1541页

作者： Lei Fu wen-bin gu Wei Li Liang Chen Yong-bao Ai Hua-lei Wang College of Field Engineering Army Engineering University of PLANanjing210007China 93182 troops People's Liberation ArmyShenyang110000China 93033 troops People's Liberation ArmyShenyang110000China Automobile NCO Academy Army Military Transportation UniversityBengbu233011China

In this paper,based on a bidirectional parallel multi-branch feature pyramid network(BPMFPN),a novel one-stage object detector called BPMFPN Det is proposed for real-time detection of ground multi-scale targets by swarm unmanned aerial vehicles(UAVs).First,the bidirectional parallel multi-branch convolution modules are used to construct the feature pyramid to enhance the feature expression abilities of different scale feature ***,the feature pyramid is integrated into the single-stage object detection framework to ensure real-time *** order to validate the effectiveness of the proposed algorithm,experiments are conducted on four *** the PASCAL VOC dataset,the proposed algorithm achieves the mean average precision(mAP)of 85.4 on the VOC 2007 test *** regard to the detection in optical remote sensing(DIOR)dataset,the proposed algorithm achieves 73.9 *** vehicle detection in aerial imagery(VEDAI)dataset,the detection accuracy of small land vehicle(slv)targets reaches 97.4 *** unmanned aerial vehicle detection and tracking(UAVDT)dataset,the proposed BPMFPN Det achieves the mAP of *** with the previous state-of-the-art methods,the results obtained by the proposed algorithm are more *** experimental results demonstrate that the proposed algorithm can effectively solve the problem of real-time detection of ground multi-scale targets in aerial images of swarm UAVs.

关键词： Aerial images Object detection Feature pyramid networks Multi-scale feature fusion Swarm UAVs

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Monitoring and Prediction of the Vibration Intensity of Seismic Waves Induced in Underwater Rock by Underwater Drilling and Blasting

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Defence Technology（防务技术） 2022年第1期18卷 109-118页

作者： Zhen-xiong Wang wen-bin gu Ting Liang Shou-tian Zhao Peng Chen Liu-fang Yu Research Institute of Chemical Defence 102205 China Armry Engineering University 210007China Archives Department of Space System100094China

All underwater drilling and blasting operations generate seismic ***,due to a lack of suitable vibration sensing instruments,most studies on the propagation of seismic waves have been limited to shorelines near construction areas or wharfs,whereas comparatively few studies have beerconducted on the larger seafloor *** address this gap,a seafloor vibration sensor system was developed and applied in this study that consists of an autonomous acquisition storage terminal,soft-ware platform,and hole-plugging device that was designed to record the blasting vibration intensities received through submarine rocks at a given measurement ***,dimensional analyses were used to derive a predictive equation for the strength of blast vibrations that considered the in fluence of the water *** combining reliable vibration data obtained using the sensor system in submarine rock and the developed predictive equation,it was determined that the water depth was ar important factor influencing the measured vibration *** results using the newly derivedequation were compared to those determined using the Sadowski equation,which is commonly used on land,and it was found that predictions using the derived equation were closer to the experimental values with an average error of less than 10%,representing a significant *** on these results the developed sensor system and preliminary theoretical basis was deemed suitable for studying the propagation behavior of submarine seismic waves generated by underwater drilling and blasting operations.

关键词： Seismic wave Underwater drilling and blasting Blasting vibration Dimensional analysis Induced seismicity

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Study on dynamic response of multi-degree-of-freedom explosion vessel system under impact load

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Defence Technology（防务技术） 2020年第4期16卷 777-786页

作者： Yun-hao Hu wen-bin gu Jian-qing Liu Jing-lin Xu Xin Liu Yang-ming Han Zhen-xiong Wang College of Field Engineering Army Engineering University of PLANanjing 210007China Unit No.78102 of PLA Chengdu 610031China Unit No.31696 of PLA Jinzhou 121017China Research Institute of Chemical Defense Beijing 102205China

In order to study the dynamic response and calculate the axial dynamic coefficient of the monolayer cylindrical explosion vessel,the wall of vessel is simplified as a multi-degree-of-freedom(MDoF) undamped elastic foundation *** the coupled motion equation and using Duhamel's integrals,the solutions in generalized coordinates of the equations under exponentially decaying loads,square wave loads and triangular wave loads are *** solutions are consistent in form with the solutions of single-degree-of-freedom(SDoF) undamped forced vibration simplified *** on the model,equivalent MDoF design method(also called MDoF dynamic coefficient method) of cylindrical explosion vessel is *** traditional method can only predict the dynamic coefficient of torus portion around the explosion center,but this method can predict that of the vessel wall at any axial n dividing point *** is verified that the prediction accuracy of this model is greatly improved compared with the SDoF model by comparing the results of this model with SDoF model and numerical simulation in different working ***,the prediction accuracy decreases as the scaled distance decreases and approaches the end of the vessel,which is related to the accuracy of the empirical formula of the implosion load,the simplification of the explosion load direction,the boundary conditions,and the loading time difference.

关键词： Explosion vessel Dynamic response Vibration analysis Dynamic coefficient Load feature

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Damage of a large-scale reinforced concrete wall caused by an explosively formed projectile(EFP)

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Defence Technology（防务技术） 2023年第10期28卷 280-297页

作者： Li-kai Hao wen-bin gu Ya-dong Zhang Qi Yuan Xing-bo Xie Shao-xin Zou Zhen Wang Ming Lu College of Field Engineering Army Engineering University of PLANanjing210000China Unit 31539 of PLA Beijing100000China Engineering Research Center of Safety and Protection of Explosion and Impact of Ministry of Education Southeast UniversityNanjing210000China Southwest University of Science and Technology Mianyang621000China

To quickly break through a reinforced concrete wall and meet the damage range requirements of rescuers entering the building,the combined damage characteristics of the reinforced concrete wall caused by EFP penetration and explosion shock wave were *** on LS-DYNA finite element software and RHT model with modified parameters,a 3D large-scale numerical model was established for simulation analysis,and the rationality of the material model parameters and numerical simulation algorithm were *** this basis,the combined damage effect of EFP penetration and explosion shock wave on reinforced concrete wall was studied,the effect of steel bars on the penetration of EFP was highlighted,and the effect of impact positions on the damage of the reinforced concrete wall was also *** results reveal that the designed shaped charge can form a crater with a large diameter and high depth on the reinforced concrete *** average crater diameter is greater than 67 cm(5.58 times of charge diameter),and crater depth is greater than 22 cm(1.83 times of charge diameter).The failure of the reinforced concrete wall is mainly caused by EFP *** only EFP penetration is considered,the average diameter and depth of the crater are 54.0 cm(4.50 times of charge diameter)and 23.7 cm(1.98 times of charge diameter),*** effect of explosion shock wave on crater depth is not significant,resulting in a slight increase in crater *** average crater depth is 24.5 cm(2.04 times of charge diameter)when the explosion shock wave is *** effect of explosion shock wave on the crater diameter is obvious,which can aggravate the damage range of the crater,and the effect gradually decreases with the increase of standoff *** with the results for a plain concrete wall,the crater diameter and crater depth of the reinforced concrete wall are reduced by 5.94%and 9.96%,*** to the case in which the steel bar is not hit,when

关键词： Reinforced concrete Explosively formed projectile(EFP) Penetration Explosion shock wave Numerical simulation

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Formation of explosively formed penetrator with fins and its flight characteristics

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Defence Technology（防务技术） 2014年第2期10卷 119-123页

作者： Jian-qing LIU wen-bin gu Ming LU Hao-ming XU Shuang-zhang WU College of Field Engineering PLA University of Science & Technology

The ultimate goal of weapon system employing an explosively formed penetrator(EFP) is to defeat a target at the longest *** order to do this,an EFP must be aerodynamically stable so as to strike the target at a small angle of obliquity,and the decay velocity per meter of EFP must be smaller at extended *** the angle of attack increases,the penetration ability of EFP greatly *** fins improve the EFP aeroballistic characteristics and decrease the flight drag of EFP as *** with fins formed by three-point initiation is *** formation of EFP with fins is studied by LS-DYNA,and the aeroballistics is studied through *** experimental results show that the decay velocity per meter of EFP with fins is much smaller than that of normal *** the attitude angle steadily decreases.

关键词：爆炸成型弹丸飞行特性散热片 LS-DYNA EFP 衰减速度武器系统动力稳定

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Simulation and experimental research on line throwing rocket with flight

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Defence Technology（防务技术） 2014年第2期10卷 149-153页

作者： wen-bin gu Ming LU Jian-qing LIU Qin-xing DONG Zhen-xiong WANG Jiang-hai CHEN College of Field Engineering PLA University of Science and Technology Wuhan Ordnance N.C.O School

The finite segment method is used to model the line throwing rocket system.A dynamic model of line throwing rocket with flight motion based on Kane's method is presented by the kinematics description of the system and the consideration of the forces acting on the *** experiment designed according to the parameters of the dynamic model is *** simulation and experiment results,such as range,velocity and flight time,are compared and *** simulation results are basically agreed with the test data,which shows that the flight motion of the line throwing rocket can be predicted by the dynamic model.A theoretical model and guide for the further research on the disturbance of rope and the guidance,flight control of line throwing rocket are provided by the dynamic modeling.

关键词：火箭系统飞行运动实验仿真动态模型有限段方法参数设计飞行时间

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震后边坡植被多样性与土壤特性的相关性研究

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四川大学学报（自然科学版） 2016年第6期53卷 1415-1422页

作者：武文娟辜彬四川大学生命科学学院成都610064

通过对四川省北川县地震后生态恢复边坡的植物群落和土壤特性进行调查,并与周边未受地震破坏的自然边坡进行对比,记录了生态恢复边坡不同坡位样地的植物物种多样性和土壤特性因子,利用PCA排序和相关分析,研究了土壤特性与边坡植被物种... 详细信息

通过对四川省北川县地震后生态恢复边坡的植物群落和土壤特性进行调查,并与周边未受地震破坏的自然边坡进行对比,记录了生态恢复边坡不同坡位样地的植物物种多样性和土壤特性因子,利用PCA排序和相关分析,研究了土壤特性与边坡植被物种多样性变化的相关关系.结果表明:与自然边坡相比,震后边坡坡下、坡中和坡上的物种多样性和土壤特性值都大幅度下降;震后边坡不同坡位的物种多样性和土壤特性差异较大,整体呈现出坡下>坡中>坡上的特点;相关分析表明,Margalef丰富度指数与碱解氮、速效钾和细菌数量呈极显著相关,Shannon-Wiener多样性指数与碱解氮、过氧化氢酶活性、细菌数量和放线菌数量呈显著相关;主成分分析结果显示,全钾含量、全磷含量、脲酶活性、蔗糖酶活性和真菌数量在北川土壤因子与物种多样性变化的协同作用中居于主导地位.

关键词：生态恢复土壤特性物种多样性相关分析 PCA

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基于双孪生网络的可见光热红外目标实时鲁棒跟踪

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吉林大学学报（工学版） 2022年第12期52卷 2906-2915页

作者：符磊顾文彬艾勇保李伟郑南王留洋陆军工程大学野战工程学院南京210007 军事科学院国防科技创新研究院北京100071 中国人民解放军93182部队沈阳110000

针对可见光与热红外图像融合跟踪中采用孪生网络架构进行跟踪时鲁棒性较差的问题,提出了一种基于双孪生网络特征融合的可见光热红外(RGB-T)目标实时跟踪方法。首先,采用两个孪生网络分别对可见光和红外图像的模板分支和搜索分支进行特... 详细信息

针对可见光与热红外图像融合跟踪中采用孪生网络架构进行跟踪时鲁棒性较差的问题,提出了一种基于双孪生网络特征融合的可见光热红外(RGB-T)目标实时跟踪方法。首先,采用两个孪生网络分别对可见光和红外图像的模板分支和搜索分支进行特征提取,得到两种模态特征层;然后,利用自注意力特征增强模块(SFEM)对两种模态的特征进行增强,并使用双模特征融合(DMFF)模块对模板分支和搜索分支增强后的特征分别进行融合;最后,将融合后的模板分支和搜索分支进行特定任务的互相关操作,并通过分类和回归分支得到目标位置,从而完成跟踪。在灰度热红外目标跟踪数据集(GTOT)上的测试结果表明,本文方法的精确率(PR)为91.8%,成功率(SR)为78.1%,运行速度为60 f/s。与其他RGB-T融合跟踪方法相比,本文方法能够在保持实时处理速度的同时具备较高的鲁棒性。

关键词：计算机应用可见光热红外双孪生网络通道注意力空间注意力

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纳米TiO_2晶粒生长动力学研究

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无机材料学报 2002年第3期17卷 429-436页

作者：刘河洲胡文彬顾明元吴人洁上海交通大学金属基复合材料国家重点实验室 200030

研究了纳米ＴｉＯ２粒子热处理过程的晶粒生长,结果表明:低于８２３Ｋ锐钛矿晶粒的长大速率较小,８２３Ｋ后锐钛矿晶粒的长大速率显著增加．锐钛矿晶粒的生长动力学符合五次方方程,表观生长活化能由于纳米尺寸和相变效应的影响在高温区... 详细信息

研究了纳米ＴｉＯ２粒子热处理过程的晶粒生长,结果表明:低于８２３Ｋ锐钛矿晶粒的长大速率较小,８２３Ｋ后锐钛矿晶粒的长大速率显著增加．锐钛矿晶粒的生长动力学符合五次方方程,表观生长活化能由于纳米尺寸和相变效应的影响在高温区和低温区表现不同,高于８２３Ｋ时为(２０１．５５±５．６２)ｋＪ/ｍｏｌ,低于８２３Ｋ时为(３８．６７±６．３７)ｋＪ/ｍｏｌ;金红石晶粒的生长符合二次方方程,表观生长活化能为(１０８．７２±５．０６)ｋＪ/ｍｏｌ．

关键词：纳米TiO2 热处理晶粒生长锐钛矿金红石活化能二氧化钛光催化剂动力学

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人工晶状体囊袋内缝线睫状沟固定术的临床应用

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国际眼科杂志 2010年第5期10卷 940-941页

作者：顾文斌杨新毕鸿耘顾宝玉叶楠中国新疆维吾尔自治区乌鲁木齐市眼耳鼻喉专科医院 830002 中国新疆乌维吾尔自治区昌吉市医院眼科 848400

目的:观察探讨人工晶状体囊袋内缝线睫状沟固定术的临床应用、手术方法及效果。方法:对19例19眼伴晶状体不全脱位和4例4眼超声乳化术或手法小切口囊外摘除术中误吸囊袋或其他操作致局限性悬韧带离断的白内障患者(悬韧带离断≥3个钟点位... 详细信息

目的:观察探讨人工晶状体囊袋内缝线睫状沟固定术的临床应用、手术方法及效果。方法:对19例19眼伴晶状体不全脱位和4例4眼超声乳化术或手法小切口囊外摘除术中误吸囊袋或其他操作致局限性悬韧带离断的白内障患者(悬韧带离断≥3个钟点位～≤6个钟点位14眼,>6个钟点位～≤9个钟点位者9眼),行计划性或术中一期人工晶状体囊袋内缝线睫状沟固定术。结果:所有患者经过6～36mo的随访,视力稳定;人工晶状体位置:正常者17眼,轻度倾斜者2眼,偏中心者4眼,瞳孔不圆者4眼,患者均无不良主诉;4眼后囊膜轻度混浊,未做处理;无固定缝线松解脱落及囊袋皱缩发生。结论:人工晶状体囊袋内缝线睫状沟固定术对伴有晶状体不全脱位、悬韧带形态异常、功能缺陷的白内障病例,临床效果好,费用低,可替代人工囊袋内张力环。

关键词：人工晶状体囊袋内缝线睫状沟固定

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