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Differential game strategy in three-player evasion and pursuit scenarios

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Journal of Systems Engineering and Electronics 2018年第2期29卷 352-366页

作者： sun qilong QI Naiming XIAO Longxu LIN Haiqi Department of Aerospace Engineering Harbin Institute of TechnologyHarbin 150001China The Rocket Force Equipment Academy Beijing 100096China

A conflict of three players, including an attacker, a defender, and a target with bounded control is discussed based on the differential game theories in which the target and the defender use an optimal pursuit strategy. The current approach chooses the miss distance as the outcome of the conflict. Different optimal guidance laws are investigated, and feasible conditions are analyzed for the attacker to accomplish an attacking task. For some given conditions, the attacker cannot intercept the target by only using a one-to-one optimal pursuit guidance law; thus, a guidance law for the attacker to reach a critical safe value is ***, the guidance law is divided into two parts. Before the engagement time between the defender and the attacker, the attacker uses this derived guidance law to guarantee that the evasion distance from the defender is safe, and that the zero-effort-miss(ZEM) distance between the attacker and the target is the *** that engagement time, the attacker uses the optimal one-toone guidance law to accomplish the pursuit task. The advantages and limited conditions of these derived guidance laws are also investigated by using nonlinear simulations.

关键词： three players differential game theory zero-effort-miss(ZEM) distance guidance law

An optimal one-way cooperative strategy for two defenders against an attacking missile

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Chinese Journal of Aeronautics 2017年第4期30卷 1506-1518页

作者： qilong sun Naiming QI Zheyao XU Yanfang LIU Yong ZHANG Department of Aerospace Engineering Harbin Institute of Technology Harbin 150001 China

This paper investigates a cooperative strategy for protecting an aerial *** problem is solved as a game among four players（a target,two defenders,and a missile）.In this scenario,the target launches two defenders（defender-1 and defender-2）simultaneously,to establish a oneway cooperation system（OCS）against an attacking missile.A new optimal evasion strategy for the target is also *** the engagement,the target takes into account the reaction of the attacking missile,and guides defender-1 to the interception point by receiving information from *** on the control effort of the target,defender-2 can choose appropriate launch conditions and use very limited maneuvering capability to intercept the *** adversaries with first-order dynamics,simulation results show that the OCS allows two defenders to intercept the *** the engagement,even if one defender or communication channel is broken,the OCS still allows an interception to be made,thus increasing the target’s survivability.

关键词： Cooperative strategy Interception Increased survivability Navigation gain One-way cooperation system

Guidance laws for attacking defended target

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Chinese Journal of Aeronautics 2019年第10期32卷 2337-2353页

作者： qilong sun Chenfeng ZHANG Ning LIU Weixue ZHOU Naiming QI Beijing Institute of Space Long March Vehicle Beijing 100076China Department of Aerospace Engineering Harbin Institute of TechnologyHarbin 150001China

In this paper,two new guidance laws based on differential game theory are proposed and investigated for the attacker in an attacker-defender-target *** conditions for the attacker winning the game are analyzed when the target and defender using the differential game guidance law based on the linear *** core ideas underlying the two guidance laws are the attacker evading to a critical safe boundary from the defender,and then maintaining a critical miss *** guidance law more appropriate for the attacker to win the game differs according to the initial *** other guidance laws,when using the derived guidance laws there is no need to know the target and the defender’s control *** results of numerical simulations show that the attacker can evade the defender and hit the target successfully by using the proposed derived guidance laws.

关键词： Attacking Control effort Differential game theory Guidance law Miss distance

Experimental study on the dynamic modulus of compacted loess under bidirectional dynamic load

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Earthquake Research Advances 2022年第3期2卷 58-66页

作者： Liguo Yang Shengjun Shao qilong sun Ping Wang Institute of Geotechnical Engineering Xi0an University of TechnologyXi0an710048China Department of Civil and Traffic Engineering Yellow River Conservancy Technical InstituteKaifeng475003China Shaanxi Key Laboratory of Loess Mechanics and Engineering Xi0an University of TechnologyXi0an710048China

The dynamic characteristics of compacted loess are of great significance to the seismic construction of the Loess Plateau area in Northwest China,where earthquakes frequently *** study the change in the dynamic modulus of the foundation soil under the combined action of vertical and horizontal earthquakes,a hollow cy-lindrical torsion shear instrument capable of vibrating in four directions was used to perform two-way coupling of compression and torsion of Xi'an compacted loess under different dry density and deviator stress *** results show that increasing the dry density can improve the initial dynamic compression modulus and initial dynamic shear modulus of compacted *** an increase in the deviator stress ratio,the initial dynamic compression modulus increases,to a certain extent,but the initial dynamic shear modulus decreases *** dynamic modulus gradually decreases with the development of dynamic strain and tends to be stable,and the dynamic modulus that reaches the same strain increases with an increasing dry *** the initial stage of dynamic loading,the attenuation of the dynamic shear modulus with the strain development is faster than that of the dynamic compression *** with previous research results,it is determined that the dynamic modulus of loess under bidirectional dynamic loading is lower and the attenuation rate is faster than that under single-direction dynamic *** deviator stress ratio has a more obvious effect on the dynamic compression *** increase in the deviator stress ratio can increase the dynamic compression modulus,to a certain ***,the deviator stress ratio has almost no effect on the dynamic shear modulus,and can therefore be ignored.

关键词： Bidirectional dynamic load Compacted loess Dynamic modulus Dry density Deviator stress ratio Ground treatment

Two-dimensional square transition metal dichalcogenides with lateral heterostructures

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Nano Research 2017年第11期10卷 3909-3919页

作者： qilong sun Ying Dai Na Yin Lin Yu Yandong Ma Wei Wei Baibiao Huang School of Physics Shandong University Jinan 250100 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

Fabrication of lateral heterostructures （LHS） is promising for a wide range of next-generation devices and could sufficiently unlock the potential of two-dimensional ***,we demonstrate the design of lateral heterostructures based on new building materials,namely 1S-MX2 LHS,using first-principles calculations.1S-MX2 LHS exhibits excellent stability,demonstrating high feasibility in the *** desired bandgap opening can endure application at room temperature and was confirmed in 1S-MX2 LHS with spin-orbit coupling （SOC）.A strain strategy further resulted in efficient bandgap engineering and an intriguing phase *** also found that black phosphorus can serve as a competent substrate to support 1S-MX2 LHS with a coveted type-Ⅱ band alignment,allowing versatile functionalized bidirectional heterostructures with built-in device ***,the robust electronic features could be maintained in the 1S-MX2 LHS with larger *** findings will not only renew interest in LHS studies by enriching their categories and properties,but also highlight the promise of these lateral heterostructures as appealing materials for future integrated devices.

关键词： two-dimensional lateral heterostructure transition metal dichalcogenide black phosphorus density functional theory

Grafting of MIPs from PVDF Membranes via Reversible Addition-fragmentation Chain Transfer Polymerization for Selective Removal of p-Hydroxybenzoic Acid

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Chemical Research in Chinese Universities 2018年第6期34卷 1051-1057页

作者： DONG Yanying YU Ping sun qilong LU Yang TAN Zhenjiang YU Xiaopeng School of Computer Science Key Laboratory of Numerical Simulation of Jilin Province School of Management Jilin Normal University Siping 136000 P. R. China

Effective molecularly imprinted membranes（MIMs） were developed as an efficient adsorbent for the selective removal ofp-hydroxybenzoic acid（p-HB） from acetylsalicylic acid（ASA, aspirin）. The MIMs were grafted successfully from poly（vinylidene fluoride） microfiltration membranes via reversible addition-fragmentation chain transfer（RAFT） polymerization. The graft copolymerization of acrylic acid（AA） in the presence of template p-hydroxybenzoic acid led to molecularly imprinted polymer（MIP） film coated membranes. The obtained MIMs were characterized by scanning electron microscopy（SEM）, Fourier transform infrared spectrophotometer（FTIR） and Raman spectra, and batch mode adsorption studies were carried ont to investigate the specific adsorption equilibrium, kinetics and selective recognition properties of different MIMs. The kinetic properties of the MIMs could be well described by the pseudo-second-order rate equation. Selective permeation experiments were performed to evaluate the permeation selectivity of the p-HB imprinted membranes. The observed performances of the MIMs are applicable to the further purification of aspirin. Keywords Acetylsalicylic acid; Reversible addition-fragmentation chain transfer; Molecularly imprinted membrane; p-Hydroxybenzoic acid; Selective adsorption

关键词： Acetylsalicylic acid Reversible addition-fragmentation chain transfer Molecularly imprinted membrane p-Hydroxybenzoic acid Selective adsorption

磁性颗粒/碳纤维轻质柔软复合材料制备及其吸波性能

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纺织学报 2019年第1期40卷 97-102页

作者：叶伟孙雷余进孙启龙南通大学安全防护用特种纤维复合材料研发国家地方联合工程研究中心江苏南通226019 南通大学纺织服装学院江苏南通226019

为开发兼具电损耗和磁损耗的新型轻质柔软吸波复合材料,采用聚丙烯腈(PAN)基预氧丝毡浸渍金属盐溶液,经高温处理工艺制备了磁性颗粒/碳纤维轻质柔软复合材料。通过弓形法吸波测试、X射线衍射、X射线能谱分析、扫描电子显微镜观察等方法... 详细信息

为开发兼具电损耗和磁损耗的新型轻质柔软吸波复合材料,采用聚丙烯腈(PAN)基预氧丝毡浸渍金属盐溶液,经高温处理工艺制备了磁性颗粒/碳纤维轻质柔软复合材料。通过弓形法吸波测试、X射线衍射、X射线能谱分析、扫描电子显微镜观察等方法对材料性能进行表征和分析。结果表明:所制备的复合材料由碳纤维和具有磁损耗性能的Fe—Co—Ni、Fe_3O_4、Fe—Ni、Fe—Co等颗粒组成,磁性颗粒沿着纤维轴向均匀分布,电损耗与磁损耗间的协同作用使磁性颗粒/碳纤维复合材料表现出优异的吸波性能。当处理温度为650℃和700℃时,试样电磁波发射损耗小于-5 d B的吸收波段分别为8. 6~18 GHz和10~18 GHz,电磁波反射损耗小于-10 d B的吸收波段分别为13. 9~18 GHz和14~18 GHz。结果表明,过高或过低的处理温度会降低材料电磁波损耗,通过调节处理温度可控制材料的吸波性能。

关键词：复合材料碳纤维金属盐磁性颗粒吸波性能

一种改进RetinaNet的室内人员检测算法

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西安电子科技大学学报 2019年第5期46卷 69-74,104页

作者：王璐璐张为孙琦龙天津大学电气自动化与信息工程学院天津300072 天津大学微电子学院天津300072 青海民族大学计算机学院青海西宁810007

由于现有的人员检测算法研究对象主要是室外直立行人,而室内人员姿态多变,且图像拍摄角度与室外行人差别较大,所以使用以往的检测方法得到的效果并不理想。基于此,笔者针对室内人员检测数据集提出了一种高精度检测模型。该模型以Retina... 详细信息

由于现有的人员检测算法研究对象主要是室外直立行人,而室内人员姿态多变,且图像拍摄角度与室外行人差别较大,所以使用以往的检测方法得到的效果并不理想。基于此,笔者针对室内人员检测数据集提出了一种高精度检测模型。该模型以RetinaNet网络为基础,在残差网络中引入通道注意力模块,间接实现卷积层的随机失活,增强模型泛化能力;通过维度聚类算法找出锚点的最佳尺寸,并据此找到合适的特征图进行预测。实验表明,这种算法在室内人员检测数据集上检测精度可达99.84%,且在速度和内存占用方面也优于其他算法。

关键词：机器视觉卷积神经网络室内人员检测

嵌入中心点预测模块的Yolov3遮挡人员检测网络

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天津大学学报（自然科学与工程技术版） 2021年第5期54卷 517-525页

作者：梁煜李佳豪张为孙琦龙天津大学微电子学院天津300072 青海民族大学计算机学院西宁810007

为解决目前实际监控场景下人员检测任务中存在的遮挡问题,提出了一种改进的Yolov3检测网络.首先,针对现有人员检测算法的被检测目标姿态单一且大多是室外直立行人的问题,自建了一个包含16832张样本的多场景人员检测数据集用于对检测网... 详细信息

为解决目前实际监控场景下人员检测任务中存在的遮挡问题,提出了一种改进的Yolov3检测网络.首先,针对现有人员检测算法的被检测目标姿态单一且大多是室外直立行人的问题,自建了一个包含16832张样本的多场景人员检测数据集用于对检测网络进行训练和测试,其中包含训练集样本12090张,测试集样本4742张.随后,为了提升网络在遮挡情况下的检测效果,设计了中心点预测模块(CPM)并将其嵌入到原Yolov3网络中3个尺度的输出特征图上,通过该模块首先确定目标的中心位置作为预提取的中心点,随后在此预提取的中心点上对目标的位置和尺寸进行精确的回归.最后,候选框的精确回归中采用广义的交并比指标来构造损失函数进行优化,通过准确地构造候选框和真实目标框的位置关系来提高其回归精度,同时降低损失函数在不同尺度目标下的波动.实验结果表明:优化网络结构和损失函数后的检测网络在测试集上的检测精度提高了2.92%,漏检率下降2.94%,针对实际监控场景下的遮挡情形取得了很好的检测效果,而且对多姿态人员目标的检测结果具有很好的鲁棒性;同时检测速度达到了28帧/s,保证了检测的实时性.另外,在Caltech行人数据库上该网络的漏检率为6.02%,相对于传统的检测网络同样达到了最优的效果,进一步印证了网络在行人检测任务上的优越性.

关键词：计算机视觉视频监控卷积神经网络人员检测人员遮挡