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Group cooperative midcourse guidance law design considering time-to-go
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作者 ZHANG Ruitao FANG Yangwang +2 位作者 CHEN Zhan GUO Hang FU Wenxing 《Journal of Systems Engineering and Electronics》 2025年第3期835-853,共19页
To solve the problem of providing the best initial situation for terminal guidance when multiple missiles intercept multiple targets,a group cooperative midcourse guidance law(GCMGL)considering time-to-go is proposed.... To solve the problem of providing the best initial situation for terminal guidance when multiple missiles intercept multiple targets,a group cooperative midcourse guidance law(GCMGL)considering time-to-go is proposed.Firstly,a threedimensional(3D)guidance model is established and a cooperative trajectory shaping guidance law is given.Secondly,for estimating the unknown target maneuvering acceleration,an adaptive disturbance observer(ADO)is designed,combining finitetime theory with a radial basis function(RBF)neural network,and the convergence of the estimation error is proven using Lyapunov stability theory.Then,to ensure time-to-go cooperation among missiles within the same group and across different groups,the group consensus protocols of virtual collision point mean and the inter-group cooperative consensus protocol are designed respectively.Based on the group consensus protocols,the virtual collision point cooperative guidance law is given,and the finite-time convergence is proved by Lyapunov stability theory.Simultaneously,combined with trajectory shaping guidance law,virtual collision point cooperative guidance law and the intergroup cooperative consensus protocol,the design of GCMGL considering time-to-go is given.Finally,numerical simulation results show the effectiveness and the superiority of the proposed GCMGL. 展开更多
关键词 cooperative midcourse guidance virtual collision point TIME-to-go finite-time theory group consensus protocol
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基于SAM和ATOM的目标跟踪算法研究
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作者 胡银记 梁振起 +1 位作者 李国强 景元萍 《电光与控制》 北大核心 2025年第3期51-55,共5页
当前目标跟踪算法往往采用目标框或分割掩模初始化模板,然而在有限操作时间或恶劣场景时却难以提供目标框或分割掩模。提出一种点提示的目标跟踪算法,其仅需要提供位于目标分割掩模中的任一图像坐标即可完成模板初始化。首先,采用SAM对... 当前目标跟踪算法往往采用目标框或分割掩模初始化模板,然而在有限操作时间或恶劣场景时却难以提供目标框或分割掩模。提出一种点提示的目标跟踪算法,其仅需要提供位于目标分割掩模中的任一图像坐标即可完成模板初始化。首先,采用SAM对图像目标进行零样本分割,获取分割掩模,求外界矩形框作为ATOM跟踪算法的输入,从而完成模板初始化;然后,采用高斯-牛顿共轭梯度法对模板在线快速学习,获得目标定位器,与离线学习的IoU预测分支共同完成目标跟踪任务;最后,根据点提示输入完成目标跟踪算法仿真。仿真结果表明,在UAV123数据集上,算法的精度P达到79.7%,AUC达到60.6%,跟踪性能相较于经典算法有一定提升,同时,FPS达到87.4帧/s,满足实时跟踪要求。 展开更多
关键词 目标跟踪 点提示 零样本分割 深度学习
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Two-to-one differential game via improved MOGWO
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作者 BAI Yu ZHOU Di +2 位作者 ZHANG Bolun HE Zhen HE Ping 《Journal of Systems Engineering and Electronics》 2025年第1期233-255,共23页
When the maneuverability of a pursuer is not significantly higher than that of an evader,it will be difficult to intercept the evader with only one pursuer.Therefore,this article adopts a two-to-one differential game ... When the maneuverability of a pursuer is not significantly higher than that of an evader,it will be difficult to intercept the evader with only one pursuer.Therefore,this article adopts a two-to-one differential game strategy,the game of kind is generally considered to be angle-optimized,which allows unlimited turns,but these practices do not take into account the effect of acceleration,which does not correspond to the actual situation,thus,based on the angle-optimized,the acceleration optimization and the acceleration upper bound constraint are added into the game for consideration.A two-to-one differential game problem is proposed in the three-dimensional space,and an improved multi-objective grey wolf optimization(IMOGWO)algorithm is proposed to solve the optimal game point of this problem.With the equations that describe the relative motions between the pursuers and the evader in the three-dimensional space,a multi-objective function with constraints is given as the performance index to design an optimal strategy for the differential game.Then the optimal game point is solved by using the IMOGWO algorithm.It is proved based on Markov chains that with the IMOGWO,the Pareto solution set is the solution of the differential game.Finally,it is verified through simulations that the pursuers can capture the escapee,and via comparative experiments,it is shown that the IMOGWO algorithm performs well in terms of running time and memory usage. 展开更多
关键词 differential game improved multi-objective grey wolf optimization(IMOGWO) cooperative pursuit optimal game point
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基于TOF激光雷达扫描的烟丝堆积体积测量研究
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作者 孙名豫 周沅桢 +3 位作者 乔俊峰 吴合典 孙榕杏 资文华 《中国烟草学报》 北大核心 2025年第3期39-47,共9页
【目的】探究TOF激光雷达扫描烟丝堆积体积在线测量应用前景。【方法】采用自主搭建的传送带烟丝堆积体积在线测量系统,研究了TOF激光雷达扫描高度、传送带颜色和运行速度对系统的影响,并对算法处理后的烟丝点云进行2.5D体积计算。【结... 【目的】探究TOF激光雷达扫描烟丝堆积体积在线测量应用前景。【方法】采用自主搭建的传送带烟丝堆积体积在线测量系统,研究了TOF激光雷达扫描高度、传送带颜色和运行速度对系统的影响,并对算法处理后的烟丝点云进行2.5D体积计算。【结果】(1)激光雷达扫描测量高度对检测点云异常值比例有较大影响,1200 mm高度扫描的点云数据比较适用于传送带烟丝堆积体积测量;传送带颜色为白色时,TOF激光雷达对传送带距离的测定误差最小;传送带运行速度40~130 mm/s范围内,点云数据量对物料扫描轮廓重建影响均较小;(2)激光雷达扫描测量高度变化过程中会出现“断层”现象,体积计算时选用interpolate模式对空缺值进行插值处理可补全断层位置,有效提高测量结果准确性。(3)基于TOF激光雷达扫描测量传送带物料堆积体积平均相对误差小于3.0%,较好地验证了该在线测量系统具有较高的测量准确度。【结论】采用TOF激光雷达扫描进行烟丝堆积体积在线测量具有良好可行性和准确性。 展开更多
关键词 toF激光雷达 烟丝堆积体积 点云处理 2.5D体积计算
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一类具有瞬时和非瞬时脉冲的ψ-Caputo型分数阶微分方程的多解性
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作者 姚旺进 张慧萍 《数学物理学报(A辑)》 北大核心 2025年第3期807-823,共17页
作为整数阶微分方程的推广,分数阶微分方程近年来是一个十分热门的研究对象.分数阶微分方程在反常扩散、流体流动、流行病学和粘弹性力学等许多科学与工程实际问题的建模中发挥着重要作用.该文研究一类包含ψ-Caputo分数阶导数和具有瞬... 作为整数阶微分方程的推广,分数阶微分方程近年来是一个十分热门的研究对象.分数阶微分方程在反常扩散、流体流动、流行病学和粘弹性力学等许多科学与工程实际问题的建模中发挥着重要作用.该文研究一类包含ψ-Caputo分数阶导数和具有瞬时和非瞬时脉冲的分数阶微分方程.当参数μ∈R时,利用变分方法和两类三临界点定理,获得至少三个古典解的存在性.并且,该文改进和推广了最近的一些结果.最后,给出两个例子来验证所得结果的可行性和有效性. 展开更多
关键词 ψ-Caputo分数阶导数 分数阶微分方程 变分方法 三临界点定理
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SIMD-to-RVV动态二进制翻译中的跨架构编程模型适配优化
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作者 赖远明 李亚龙 +3 位作者 胡瀚之 谢梦瑶 王喆 武成岗 《计算机研究与发展》 北大核心 2025年第6期1469-1491,共23页
RISC-V因其开源和模块化设计等特性,已在嵌入式领域取得显著成功,并逐步向高性能计算(HPC)领域拓展.面向HPC的RISC-V硬件(如Sophon SG2042多核处理器)已展现出与x86/ARM同类型产品相当的性能水平,但不完善的软件生态是阻碍其发展的最大... RISC-V因其开源和模块化设计等特性,已在嵌入式领域取得显著成功,并逐步向高性能计算(HPC)领域拓展.面向HPC的RISC-V硬件(如Sophon SG2042多核处理器)已展现出与x86/ARM同类型产品相当的性能水平,但不完善的软件生态是阻碍其发展的最大障碍之一.开发了面向RISC-V的进程级动态二进制翻译(DBT)器RVBT,用于将成熟的x86软件生态移植到RISC-V平台,加速RISC-V在HPC领域的应用进程.针对HPC程序广泛依赖SIMD指令的特性,聚焦于解决SIMD与RVV间显著的编程模型差异导致的翻译性能瓶颈问题,提出了3项创新的优化方案.x86SIMD将数据类型硬编码于操作码,而RVV需动态配置vtype和掩码寄存器,这导致直接翻译产生了大量冗余操作,严重拉低了翻译运行的效率.通过充分利用程序数据类型的局部性,优化方案可删除跨架构适配编程模型导致的冗余设置,混合使用浮点扩展和向量扩展翻译SIMD指令并按需同步数据,大幅提升了SIMD指令的翻译运行效率.3项优化方案具备通用性,也适用于ARM平台的SIMD到RVV的翻译.实验表明,以SPECCPU2006作为测试集,优化方案对csrr,vsetvl,vsetvli指令的平均动态消除率分别达到了100%,100%和56.31%,在浮点测试集上,掩码设置操作的平均动态消除率达到了74.66%,数据的平均动态同步率为67.35%.优化后的RVBT在整点和浮点测试集上的平均运行效率达到了本地执行的47.39%和40.06%,相比优化前的加速比分别为1.21和8.31,并远超QEMU18.84%和4.81%,展现出了应用于部分HPC场景的潜力. 展开更多
关键词 二进制翻译 RISC-V向量扩展 x86SIMD 跨架构编程模型适配 浮点计算 冗余设置消除 混合翻译
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The Applied Research of Fracture in Three-point Bending to Blanking of Bearing Steel
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作者 Youtang Li Ping Ma Changfeng Yan 《上海交通大学学报》 EI CAS CSCD 北大核心 2004年第z2期199-205,共7页
The application of fracture in three-point bending to blanking of bearing steel is studied in this paper. Several mechanical models of stress blanking are discussed at first. And then the experiments have been made in... The application of fracture in three-point bending to blanking of bearing steel is studied in this paper. Several mechanical models of stress blanking are discussed at first. And then the experiments have been made in special equipment of three-point bending designed by us. Several problems, such as the suitable span, the relations between bending and tension bending complex, the ratio of blanking length to the diameter, the relations of blank length to force, the feature of fracture, are studied through the experiments. The suitable parameters of three-point bending to blanking, depth and tip radius of notch and the ratio between blanking length and stick diameter have been proposed. 展开更多
关键词 BEARING steel three points BENDING BLANKING CRACK technique FRACTURE design
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基于TOF相机的振动筛上物料状态动态监测方法 被引量:1
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作者 卢军 谭兴富 +2 位作者 成举炳 华智诚 刘畅 《煤炭工程》 北大核心 2024年第9期202-210,共9页
振动筛筛上物料载荷异常不仅影响生产效率还可能导致安全隐患,实时准确地监测筛上物料状态具有重要意义。针对传统人工监测方法劳动强度大、速度慢、有极高安全隐患并且不容易发现设备微小故障等问题。基于TOF相机物料动态监测技术,提... 振动筛筛上物料载荷异常不仅影响生产效率还可能导致安全隐患,实时准确地监测筛上物料状态具有重要意义。针对传统人工监测方法劳动强度大、速度慢、有极高安全隐患并且不容易发现设备微小故障等问题。基于TOF相机物料动态监测技术,提出了一种联合KD树与帧差法的点云数据补全方法和基于曲面重构的筛上物料动态监测方法。该点云数据补全方法有效修补了因筛上物料表面水分和物料缝隙导致的TOF相机拍摄过程中的点云数据缺失问题,通过对补全后的筛上物料进行点云曲面重构分析,判断欠载、过载、左偏载和右偏载四种筛上物料状态,实时监测筛上物料状态。研究通过TOF相机直接获取筛上物料状态信息,对筛上物料实时检测,减少了人工干预的需求且具备实时性。为筛上物料状态实时监测问题提供了一个可靠的解决方案。 展开更多
关键词 振动筛 toF相机 3D点云 计算机视觉 筛面监测
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Automatic three-dimensional reconstruction based on four-view stereo vision using checkerboard pattern 被引量:5
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作者 XIONG Jie ZHONG Si-dong +1 位作者 LIU Yong TU Li-fen 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1063-1072,共10页
An automatic three-dimensional(3D) reconstruction method based on four-view stereo vision using checkerboard pattern is presented. Mismatches easily exist in traditional binocular stereo matching due to the repeatable... An automatic three-dimensional(3D) reconstruction method based on four-view stereo vision using checkerboard pattern is presented. Mismatches easily exist in traditional binocular stereo matching due to the repeatable or similar features of binocular images. In order to reduce the probability of mismatching and improve the measure precision, a four-camera measurement system which can add extra matching constraints and offer multiple measurements is applied in this work. Moreover, a series of different checkerboard patterns are projected onto the object to obtain dense feature points and remove mismatched points. Finally, the 3D model is generated by performing Delaunay triangulation and texture mapping on the point cloud obtained by four-view matching. This method was tested on the 3D reconstruction of a terracotta soldier sculpture and the Buddhas in the Mogao Grottoes. Their point clouds without mismatched points were obtained and less processing time was consumed in most cases relative to binocular matching. These good reconstructed models show the effectiveness of the method. 展开更多
关键词 three-dimensional reconstruction four-view STEREO VISION CHECKERBOARD pattern DENSE point
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Spectral matching algorithm based on nonsubsampled contourlet transform and scale-invariant feature transform 被引量:4
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作者 Dong Liang Pu Yan +2 位作者 Ming Zhu Yizheng Fan Kui Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期453-459,共7页
A new spectral matching algorithm is proposed by us- ing nonsubsampled contourlet transform and scale-invariant fea- ture transform. The nonsubsampled contourlet transform is used to decompose an image into a low freq... A new spectral matching algorithm is proposed by us- ing nonsubsampled contourlet transform and scale-invariant fea- ture transform. The nonsubsampled contourlet transform is used to decompose an image into a low frequency image and several high frequency images, and the scale-invariant feature transform is employed to extract feature points from the low frequency im- age. A proximity matrix is constructed for the feature points of two related images. By singular value decomposition of the proximity matrix, a matching matrix (or matching result) reflecting the match- ing degree among feature points is obtained. Experimental results indicate that the proposed algorithm can reduce time complexity and possess a higher accuracy. 展开更多
关键词 point pattern matching nonsubsampled contourlet transform scale-invariant feature transform spectral algorithm.
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猪圆环病毒3型LAMP-PfAgo检测方法的建立
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作者 祁钊 余相宇 +1 位作者 陈魏圆 宋祥军 《西北农林科技大学学报(自然科学版)》 北大核心 2025年第2期1-9,31,共10页
【目的】利用PfAgo蛋白结合环介导等温扩增技术(LAMP)建立一种新的PCV3检测方法LAMP-PfAgo法,用于PCV3的快速鉴别诊断。【方法】PCR扩增PCV3 Rep基因,构建重组阳性质粒pMD19-T-PCV3-Rep,对其进行PCR和测序鉴定。根据PCV3 Rep基因的保守... 【目的】利用PfAgo蛋白结合环介导等温扩增技术(LAMP)建立一种新的PCV3检测方法LAMP-PfAgo法,用于PCV3的快速鉴别诊断。【方法】PCR扩增PCV3 Rep基因,构建重组阳性质粒pMD19-T-PCV3-Rep,对其进行PCR和测序鉴定。根据PCV3 Rep基因的保守区域设计PCV3-T1~PCV3-T4等4组引物(每组包括1对内引物和1对外引物),以pMD19-T-PCV3-Rep为模板进行LAMP,筛选最佳引物组,并对LAMP反应的Mg ^(2+)浓度、内外引物浓度、反应温度、反应时间进行优化。根据PCV3 Rep基因的保守序列,设计PCV3-gs1~PCV3-gs5等5组gDNAs和一条特异性探针,进行LAMP-PfAgo反应,筛选最佳的gDNAs,并对LAMP-PfAgo反应体系中PfAgo蛋白浓度、gDNAs浓度、Mn 2+浓度和反应时间进行优化。对该LAMP-PfAgo方法的特异性、敏感性进行评价;并用该方法和实时荧光定量PCR方法对疑似感染PCV3的46份临床样品进行检测,比较结果的一致性。【结果】重组阳性质粒pMD19-T-PCV3-Rep PCR和测序均获得了891 bp的序列,表明重组阳性质粒构建成功。LAMP最佳引物为PCV3-T1,最佳Mg ^(2+)终浓度为6 mmol/L,最佳内外引物终浓度分别为1.6和1.2μmol/L,最适的反应温度65℃,最佳反应时间60 min。使用优化后的LAMP反应条件对PCV3 Rep基因保守序列进行扩增,并将其用于后续试验。LAMP-PfAgo反应最佳的gDNAs为PCV3-gs1;优化后的PfAgo蛋白终浓度为40 U/μL,gDNAs终浓度为1.50μmol/L,Mn 2+终浓度为1.50 mmol/L,反应时间为30 min。LAMP-PfAgo法的灵敏度为10拷贝/μL,且与猪圆环病毒2型、猪细小病毒、猪繁殖与呼吸综合征病毒、猪传染性胃肠炎病毒、猪瘟病毒及猪伪狂犬病毒等常见猪源病原核酸无交叉反应。临床样本检测结果显示,LAMP-PfAgo法与实时荧光定量PCR方法检测结果的符合率为100%。【结论】基于PfAgo蛋白结合LAMP技术建立了对PCV3的核酸检测方法,该方法灵敏度高和特异性强,具有潜在的临床应用价值。 展开更多
关键词 猪圆环病毒3型 PfAgo 环介导等温扩增 即时检验
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Probabilistic modeling of multifunction radars with autoregressive kernel mixture network
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作者 Hancong Feng Kaili.Jiang +4 位作者 Zhixing Zhou Yuxin Zhao Kailun Tian Haixin Yan Bin Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期275-288,共14页
The task of modeling and analyzing intercepted multifunction radars(MFRs)pulse trains is vital for cognitive electronic reconnaissance.Existing methodologies predominantly rely on prior information or heavily constrai... The task of modeling and analyzing intercepted multifunction radars(MFRs)pulse trains is vital for cognitive electronic reconnaissance.Existing methodologies predominantly rely on prior information or heavily constrained models,posing challenges for non-cooperative applications.This paper introduces a novel approach to model MFRs using a Bayesian network,where the conditional probability density function is approximated by an autoregressive kernel mixture network(ARKMN).Utilizing the estimated probability density function,a dynamic programming algorithm is proposed for denoising and detecting change points in the intercepted MFRs pulse trains.Simulation results affirm the proposed method's efficacy in modeling MFRs,outperforming the state-of-the-art in pulse train denoising and change point detection. 展开更多
关键词 Probabilistic forecasting Multifunction radar Unsupervised learning Change point detection Outlier detection
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New sigma point filtering algorithms for nonlinear stochastic systems with correlated noises 被引量:2
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作者 王小旭 潘泉 +1 位作者 程咏梅 赵春晖 《Journal of Central South University》 SCIE EI CAS 2012年第4期1010-1020,共11页
New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated no... New sigma point filtering algorithms, including the unscented Kalman filter (UKF) and the divided difference filter (DDF), are designed to solve the nonlinear filtering problem under the condition of correlated noises. Based on the minimum mean square error estimation theory, the nonlinear optimal predictive and correction recursive formulas under the hypothesis that the input noise is correlated with the measurement noise are derived and can be described in a unified framework. Then, UKF and DDF with correlated noises are proposed on the basis of approximation of the posterior mean and covariance in the unified framework by using unscented transformation and second order Stirling's interpolation. The proposed UKF and DDF with correlated noises break through the limitation that input noise and measurement noise must be assumed to be uneorrelated in standard UKF and DDF. Two simulation examples show the effectiveness and feasibility of new algorithms for dealing with nonlinear filtering issue with correlated noises. 展开更多
关键词 nonlinear system correlated noise sigma point unscented Kalman filter divided difference filter
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Summed volume region selection based three-dimensional automatic target recognition for airborne LIDAR 被引量:2
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作者 Qi-shu Qian Yi-hua Hu +2 位作者 Nan-xiang Zhao Min-le Li Fu-cai Shao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期535-542,共8页
Airborne LIDAR can flexibly obtain point cloud data with three-dimensional structural information,which can improve its effectiveness of automatic target recognition in the complex environment.Compared with 2D informa... Airborne LIDAR can flexibly obtain point cloud data with three-dimensional structural information,which can improve its effectiveness of automatic target recognition in the complex environment.Compared with 2D information,3D information performs better in separating objects and background.However,an aircraft platform can have a negative influence on LIDAR obtained data because of various flight attitudes,flight heights and atmospheric disturbances.A structure of global feature based 3D automatic target recognition method for airborne LIDAR is proposed,which is composed of offline phase and online phase.The performance of four global feature descriptors is compared.Considering the summed volume region(SVR) discrepancy in real objects,SVR selection is added into the pre-processing operations to eliminate mismatching clusters compared with the interested target.Highly reliable simulated data are obtained under various sensor’s altitudes,detection distances and atmospheric disturbances.The final experiments results show that the added step increases the recognition rate by above 2.4% and decreases the execution time by about 33%. 展开更多
关键词 3D automatic target recognition Point cloud LIDAR AIRBORNE Global feature descriptor
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Cluster segmentation algorithm based on the Vicsek with static summoning points 被引量:1
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作者 MA Yan MAO Zhaoyong +4 位作者 QIN Jian MENG Xiangyao XIAO Yujie CHEN Jianhua FENG Wei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期607-618,共12页
Because of the low convergence efficiency of the typical Vicsek model,a Vicsek with static summoning points(VSSP)algorithm based on the Vicsek model considering static summoning points is proposed.Firstly,the mathemat... Because of the low convergence efficiency of the typical Vicsek model,a Vicsek with static summoning points(VSSP)algorithm based on the Vicsek model considering static summoning points is proposed.Firstly,the mathematical model of the individual movement total cost on each summoning point is established.Then the individual classification rule is designed according to the initial state of the cluster to obtain the subclusters guided by each summoning point.Finally,the summoning factor is introduced to modify the course angle updating formula of the Vicsek model.To verify the effectiveness of the proposed algorithm and study the effect of the cluster summoning factor on the convergence rate,three groups of simulation experiments under different summoning factors are designed in this paper.To verify the superiority of the VSSP algorithm,the performance of the VSSP algorithm is compared with the classic algorithm by designing the algorithm performance comparison verification experiment.The results show that the algorithm proposed in this paper has good convergence and course angle consistency.The summoning factor is the sensitive factor of cluster convergence.This algorithm can provide a reference for efficient cluster segmentation movement. 展开更多
关键词 static summoning point Vicsek model summoning factor cluster system
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A method to determine the shell layout scheme for equipment battlefield damage tests under artillery fire 被引量:1
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作者 Cai Chen Quan Shi +2 位作者 Zhi-feng You Hong-yu Ge Fang Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期682-691,共10页
In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method i... In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method is based on the analysis of the impact point distribution and effective damage area of equipment.In order to obtain the position of the impact points,an impact point distribution model under artillery fire was established.Similarly,in order to obtain the effective damage area of equipment,the concepts of generalized damage area and task-based equipment functional damage probability were demonstrated,and the corresponding calculation model was established.Through case analysis,the shell layout scheme was effectively obtained,verifying the correctness of the proposed method. 展开更多
关键词 Battlefield damage test Projectile impact point Effective damage area Functional damage
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Traffic assignment problem under tradable credit scheme in a bi-modal stochastic transportation network: A cumulative prospect theory approach 被引量:3
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作者 HAN Fei ZHAO Xiang-mo CHENG Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期180-197,共18页
The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertain... The traffic equilibrium assignment problem under tradable credit scheme(TCS) in a bi-modal stochastic transportation network is investigated in this paper. To describe traveler’s risk-taking behaviors under uncertainty, the cumulative prospect theory(CPT) is adopted. Travelers are assumed to choose the paths with the minimum perceived generalized path costs, consisting of time prospect value(PV) and monetary cost. At equilibrium with a given TCS, the endogenous reference points and credit price remain constant, and are consistent with the equilibrium flow pattern and the corresponding travel time distributions of road sub-network. To describe such an equilibrium state, the CPT-based stochastic user equilibrium(SUE) conditions can be formulated under TCS. An equivalent variational inequality(VI) model embedding a parameterized fixed point(FP) model is then established, with its properties analyzed theoretically. A heuristic solution algorithm is developed to solve the model, which contains two-layer iterations. The outer iteration is a bisection-based contraction method to find the equilibrium credit price, and the inner iteration is essentially the method of successive averages(MSA) to determine the corresponding CPT-based SUE network flow pattern. Numerical experiments are provided to validate the model and algorithm. 展开更多
关键词 tradable credit scheme cumulative prospect theory endogenous reference points generalized path costs stochastic user equilibrium variational inequality model heuristic solution algorithm
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A sparse algorithm for adaptive pruning least square support vector regression machine based on global representative point ranking 被引量:2
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作者 HU Lei YI Guoxing HUANG Chao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期151-162,共12页
Least square support vector regression(LSSVR)is a method for function approximation,whose solutions are typically non-sparse,which limits its application especially in some occasions of fast prediction.In this paper,a... Least square support vector regression(LSSVR)is a method for function approximation,whose solutions are typically non-sparse,which limits its application especially in some occasions of fast prediction.In this paper,a sparse algorithm for adaptive pruning LSSVR algorithm based on global representative point ranking(GRPR-AP-LSSVR)is proposed.At first,the global representative point ranking(GRPR)algorithm is given,and relevant data analysis experiment is implemented which depicts the importance ranking of data points.Furthermore,the pruning strategy of removing two samples in the decremental learning procedure is designed to accelerate the training speed and ensure the sparsity.The removed data points are utilized to test the temporary learning model which ensures the regression accuracy.Finally,the proposed algorithm is verified on artificial datasets and UCI regression datasets,and experimental results indicate that,compared with several benchmark algorithms,the GRPR-AP-LSSVR algorithm has excellent sparsity and prediction speed without impairing the generalization performance. 展开更多
关键词 least square support vector regression(LSSVR) global representative point ranking(GRPR) initial training dataset pruning strategy SPARSITY regression accuracy
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Analytical Properties of Solutions and First Integrals of a Class of the Third-Order Autonomous Systems
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作者 CHEN Yang I.P.Martynov 《重庆理工大学学报(自然科学)》 CAS 北大核心 2018年第6期199-204,共6页
The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of g... The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of general solutions,instances of availability logarithmic branch points).The method for constructing the first integrals of the systems under consideration is indicated. 展开更多
关键词 MEROMORPHIC function logarithmic branch POINT FIRST INTEGRAL
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Utilization of Livestock's Dejection as Biogas Origin in Building New Countryside in Heilongjiang Province--Developing Utilization of Biogas and Promoting Energy-saving and Emission Reduction
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作者 SHEN Xueqing CUI Lijuan ZHOU Dongxing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期91-96,共6页
With the startup and execution of new socialistic countryside construction in Heilongjiang Province,the transition from castoff to resource is strengthened in the countryside,aiming at neat appearance of the countrysi... With the startup and execution of new socialistic countryside construction in Heilongjiang Province,the transition from castoff to resource is strengthened in the countryside,aiming at neat appearance of the countryside,clean production and saving energy.People produce biogas and provide the countryside with new energy by means of turning livestock's dejection into resources,composting of the plant and animal's leavings in the courtyard and even in the factory.It is helpful for the countryside to conserve the energy and reduce emission of the waste.And it also plays an important role in protecting the eco-environment,beautifying homestead and developing the ecological agriculture and so on.The liquid and solid residue in the biogas production can be reused as fertilizer for crops or food for animals after pretreatment,which is propitious to accelerate the development of the circular economy in Heilongjiang Province. 展开更多
关键词 new socialistic countryside construction composting of livestock's dejection energy saving and emission reduction
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