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基于DHPA^(*)-DSACO算法的AGV路径规划研究
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作者 王俊岭 刘佳年 +1 位作者 边俊君 王振东 《机床与液压》 北大核心 2025年第5期15-23,共9页
自主引导车(AGV)的路径规划算法是确保其正常运行的关键部分。针对A^(*)算法在路径规划过程中存在的搜索效率低、路径曲率大的问题,以及蚁群ACO算法收敛速度慢和对参数敏感等缺陷,提出一种动态启发式惩罚A^(*)与动态感知蚁群优化算法相... 自主引导车(AGV)的路径规划算法是确保其正常运行的关键部分。针对A^(*)算法在路径规划过程中存在的搜索效率低、路径曲率大的问题,以及蚁群ACO算法收敛速度慢和对参数敏感等缺陷,提出一种动态启发式惩罚A^(*)与动态感知蚁群优化算法相融合的算法—DHPA^(*)-DSACO。DHPA^(*)算法通过设置动态权重因子,结合父节点启发距离,并引入转弯惩罚项,以降低运行时间和路径曲率。DSACO算法通过设置自适应蚁群启发因子和动态挥发因子,优化信息素更新策略,从而缩短路径长度。同时,该算法利用B样条曲线对路径进行平滑处理。为验证算法的可行性,在PyCharm环境中将DHPA^(*)-DSACO算法与其他算法进行对比测试,并对实验结果进行了分析。最后,为了模拟真实世界中的情况,基于ROS系统建立仿真平台,验证了DHPA^(*)-DSACO算法的有效性。结果表明:DHPA^(*)-DSACO算法有效降低了路径长度、曲率和运行时间,显著提升了运行效率。此外,该算法还能有效避免算法陷入局部最优解,减少收敛迭代次数,进一步增强了算法的鲁棒性,使其更好地适应AGV的实际运行情况。 展开更多
关键词 路径规划 蚁群算法 A^(*)算法 B样条曲线
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基于可靠性分析的DSA200型受电弓检修参数优化研究
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作者 毛永文 李勇 《机械强度》 北大核心 2025年第2期103-110,共8页
针对DSA200型受电弓预防维修存在欠维修或过维修问题,提出一种利用受电弓失效数据来优化检查维修参数的方法。首先,利用图参数法对受电弓部件失效数据进行分析,拟合失效时间分布模型,初步判定失效数据服从指数分布,进一步采用Bartlett值... 针对DSA200型受电弓预防维修存在欠维修或过维修问题,提出一种利用受电弓失效数据来优化检查维修参数的方法。首先,利用图参数法对受电弓部件失效数据进行分析,拟合失效时间分布模型,初步判定失效数据服从指数分布,进一步采用Bartlett值法,验证失效数据服从指数分布的有效性;其次,基于受电弓组成结构和工作特性,构建受电弓为各部件串联的可靠性框图模型,根据受电弓部件具有恒定失效率特征,得出受电弓失效率;再次,建立受电弓预防性维修和更换最小费用模型,得到受电弓最优预防性维修的间隔时间和最优备件数量;最后,利用故障树分析法,分析受电弓部件的结构重要度、概率重要度和关键重要度,得出受电弓故障概率及检查维修中重点关注的部件。优化后的受电弓检查维修参数能够为检修人员提升维修水平和降低维修成本提供科学参考。 展开更多
关键词 dsa200型受电弓 指数分布 检修间隔时间 备件数量 故障树分析法
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DSA阳极表征及电催化氧化络合态废水的研究
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作者 吴金健 郑元武 +3 位作者 许海亮 钟晓丽 陈伟龙 毋浪鹏 《水处理技术》 北大核心 2025年第3期72-79,共8页
络合态废水由于其具有强络合性从而难以被常规污水处理工艺处理。本研究通过选用Ti/PbO2极板,采用电催化氧化(EO)与次氯酸钠氧化组合工艺成功实现了对实际络合态重金属废水的处理。通过电化学工作站对实际应用中较多的三种DSA阳极的电... 络合态废水由于其具有强络合性从而难以被常规污水处理工艺处理。本研究通过选用Ti/PbO2极板,采用电催化氧化(EO)与次氯酸钠氧化组合工艺成功实现了对实际络合态重金属废水的处理。通过电化学工作站对实际应用中较多的三种DSA阳极的电催化性能进行分析,并探究其实际废水处理效果、加速寿命以及成本等,结果表明Ti/PbO2极板电催化性能最佳且成本效益最高。实际废水实验结果表明,络合态废水在电流密度为80 A·m^(-2)下电催化氧化2.5 h,投加200 m L/L次氯酸钠氧化1 h,出水Ni和Zn质量浓度分别为0.214、0.14 mg/L,满足浙江省电镀水污染物排放标准(DB33/2260-2020)的要求,同时运行成本降低了37%,成功实现了降本增效。此外,通过研究络合态Ni的去除规律与处理过程中的氮素变化,探究出电催化氧化工艺具有预氧化破络效果。 展开更多
关键词 dsa阳极 阳极材料表征 电催化氧化 络合态废水 预氧化破络
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Research on Euclidean Algorithm and Reection on Its Teaching
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作者 ZHANG Shaohua 《应用数学》 北大核心 2025年第1期308-310,共3页
In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and t... In this paper,we prove that Euclid's algorithm,Bezout's equation and Divi-sion algorithm are equivalent to each other.Our result shows that Euclid has preliminarily established the theory of divisibility and the greatest common divisor.We further provided several suggestions for teaching. 展开更多
关键词 Euclid's algorithm Division algorithm Bezout's equation
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An Algorithm for Cloud-based Web Service Combination Optimization Through Plant Growth Simulation
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作者 Li Qiang Qin Huawei +1 位作者 Qiao Bingqin Wu Ruifang 《系统仿真学报》 北大核心 2025年第2期462-473,共12页
In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-base... In order to improve the efficiency of cloud-based web services,an improved plant growth simulation algorithm scheduling model.This model first used mathematical methods to describe the relationships between cloud-based web services and the constraints of system resources.Then,a light-induced plant growth simulation algorithm was established.The performance of the algorithm was compared through several plant types,and the best plant model was selected as the setting for the system.Experimental results show that when the number of test cloud-based web services reaches 2048,the model being 2.14 times faster than PSO,2.8 times faster than the ant colony algorithm,2.9 times faster than the bee colony algorithm,and a remarkable 8.38 times faster than the genetic algorithm. 展开更多
关键词 cloud-based service scheduling algorithm resource constraint load optimization cloud computing plant growth simulation algorithm
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Multi-QoS routing algorithm based on reinforcement learning for LEO satellite networks 被引量:1
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作者 ZHANG Yifan DONG Tao +1 位作者 LIU Zhihui JIN Shichao 《Journal of Systems Engineering and Electronics》 2025年第1期37-47,共11页
Low Earth orbit(LEO)satellite networks exhibit distinct characteristics,e.g.,limited resources of individual satellite nodes and dynamic network topology,which have brought many challenges for routing algorithms.To sa... Low Earth orbit(LEO)satellite networks exhibit distinct characteristics,e.g.,limited resources of individual satellite nodes and dynamic network topology,which have brought many challenges for routing algorithms.To satisfy quality of service(QoS)requirements of various users,it is critical to research efficient routing strategies to fully utilize satellite resources.This paper proposes a multi-QoS information optimized routing algorithm based on reinforcement learning for LEO satellite networks,which guarantees high level assurance demand services to be prioritized under limited satellite resources while considering the load balancing performance of the satellite networks for low level assurance demand services to ensure the full and effective utilization of satellite resources.An auxiliary path search algorithm is proposed to accelerate the convergence of satellite routing algorithm.Simulation results show that the generated routing strategy can timely process and fully meet the QoS demands of high assurance services while effectively improving the load balancing performance of the link. 展开更多
关键词 low Earth orbit(LEO)satellite network reinforcement learning multi-quality of service(QoS) routing algorithm
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联影集团重磅推出智慧仿生空中机器人DSA uAngio AVIVA 及ulnterv C550经皮介入手术机器人
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作者 《中国医学计算机成像杂志》 北大核心 2025年第1期106-106,共1页
在传统经皮介入手术中,医生依赖CT图像在脑海中构建肿瘤位置,然后进行多次尝试性穿刺和CT扫描验证。这种方式存在缺乏实时准确的术区信息感知、对医生技术依赖性大等临床痛点。手术机器人的应用,可以极大降低前述困难。经皮穿刺手术机... 在传统经皮介入手术中,医生依赖CT图像在脑海中构建肿瘤位置,然后进行多次尝试性穿刺和CT扫描验证。这种方式存在缺乏实时准确的术区信息感知、对医生技术依赖性大等临床痛点。手术机器人的应用,可以极大降低前述困难。经皮穿刺手术机器人也成为了行业探索的重要方向之一。 展开更多
关键词 CT图像 手术机器人 空中机器人 信息感知 AVI CT扫描 dsa 肿瘤位置
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Research on three-dimensional attack area based on improved backtracking and ALPS-GP algorithms of air-to-air missile
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作者 ZHANG Haodi WANG Yuhui HE Jiale 《Journal of Systems Engineering and Electronics》 2025年第1期292-310,共19页
In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of t... In the field of calculating the attack area of air-to-air missiles in modern air combat scenarios,the limitations of existing research,including real-time calculation,accuracy efficiency trade-off,and the absence of the three-dimensional attack area model,restrict their practical applications.To address these issues,an improved backtracking algorithm is proposed to improve calculation efficiency.A significant reduction in solution time and maintenance of accuracy in the three-dimensional attack area are achieved by using the proposed algorithm.Furthermore,the age-layered population structure genetic programming(ALPS-GP)algorithm is introduced to determine an analytical polynomial model of the three-dimensional attack area,considering real-time requirements.The accuracy of the polynomial model is enhanced through the coefficient correction using an improved gradient descent algorithm.The study reveals a remarkable combination of high accuracy and efficient real-time computation,with a mean error of 91.89 m using the analytical polynomial model of the three-dimensional attack area solved in just 10^(-4)s,thus meeting the requirements of real-time combat scenarios. 展开更多
关键词 air combat three-dimensional attack area improved backtracking algorithm age-layered population structure genetic programming(ALPS-GP) gradient descent algorithm
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Topological optimization of metamaterial absorber based on improved estimation of distribution algorithm
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作者 TAO Shifei LIU Beichen +2 位作者 LIU Sixing WU Fan WANG Hao 《Journal of Systems Engineering and Electronics》 2025年第3期634-641,共8页
An improved estimation of distribution algorithm(IEDA)is proposed in this paper for efficient design of metamaterial absorbers.This algorithm establishes a probability model through the selected dominant groups and sa... An improved estimation of distribution algorithm(IEDA)is proposed in this paper for efficient design of metamaterial absorbers.This algorithm establishes a probability model through the selected dominant groups and samples from the model to obtain the next generation,avoiding the problem of building-blocks destruction caused by crossover and mutation.Neighboring search from artificial bee colony algorithm(ABCA)is introduced to enhance the local optimization ability and improved to raise the speed of convergence.The probability model is modified by boundary correction and loss correction to enhance the robustness of the algorithm.The proposed IEDA is compared with other intelligent algorithms in relevant references.The results show that the proposed IEDA has faster convergence speed and stronger optimization ability,proving the feasibility and effectiveness of the algorithm. 展开更多
关键词 METAMATERIAL topological optimization estimation of distribution algorithm
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An improved genetic algorithm for causal discovery
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作者 MAO Tengjiao BU Xianjin +2 位作者 CAI Chunxiao LU Yue DU Jing 《Journal of Systems Engineering and Electronics》 2025年第3期768-777,共10页
The learning algorithms of causal discovery mainly include score-based methods and genetic algorithms(GA).The score-based algorithms are prone to searching space explosion.Classical GA is slow to converge,and prone to... The learning algorithms of causal discovery mainly include score-based methods and genetic algorithms(GA).The score-based algorithms are prone to searching space explosion.Classical GA is slow to converge,and prone to falling into local optima.To address these issues,an improved GA with domain knowledge(IGADK)is proposed.Firstly,domain knowledge is incorporated into the learning process of causality to construct a new fitness function.Secondly,a dynamical mutation operator is introduced in the algorithm to accelerate the convergence rate.Finally,an experiment is conducted on simulation data,which compares the classical GA with IGADK with domain knowledge of varying accuracy.The IGADK can greatly reduce the number of iterations,populations,and samples required for learning,which illustrates the efficiency and effectiveness of the proposed algorithm. 展开更多
关键词 genetic algorithm(GA) causal discovery convergence rate fitness function mutation operator
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Multi-platform collaborative MRC-PSO algorithm for anti-ship missile path planning
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作者 LIU Gang GUO Xinyuan +2 位作者 HUANG Dong CHEN Kezhong LI Wu 《Journal of Systems Engineering and Electronics》 2025年第2期494-509,共16页
To solve the problem of multi-platform collaborative use in anti-ship missile (ASM) path planning, this paper pro-posed multi-operator real-time constraints particle swarm opti-mization (MRC-PSO) algorithm. MRC-PSO al... To solve the problem of multi-platform collaborative use in anti-ship missile (ASM) path planning, this paper pro-posed multi-operator real-time constraints particle swarm opti-mization (MRC-PSO) algorithm. MRC-PSO algorithm utilizes a semi-rasterization environment modeling technique and inte-grates the geometric gradient law of ASMs which distinguishes itself from other collaborative path planning algorithms by fully considering the coupling between collaborative paths. Then, MRC-PSO algorithm conducts chunked stepwise recursive evo-lution of particles while incorporating circumvent, coordination, and smoothing operators which facilitates local selection opti-mization of paths, gradually reducing algorithmic space, accele-rating convergence, and enhances path cooperativity. Simula-tion experiments comparing the MRC-PSO algorithm with the PSO algorithm, genetic algorithm and operational area cluster real-time restriction (OACRR)-PSO algorithm, which demon-strate that the MRC-PSO algorithm has a faster convergence speed, and the average number of iterations is reduced by approximately 75%. It also proves that it is equally effective in resolving complex scenarios involving multiple obstacles. More-over it effectively addresses the problem of path crossing and can better satisfy the requirements of multi-platform collabora-tive path planning. The experiments are conducted in three col-laborative operation modes, namely, three-to-two, three-to-three, and four-to-two, and the outcomes demonstrate that the algorithm possesses strong universality. 展开更多
关键词 anti-ship missiles multi-platform collaborative path planning particle swarm optimization(PSO)algorithm
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联合Landsat 8与Sentinel-2的煤火探测——以将军戈壁矿区为例
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作者 朱艳茵 顾皓天 +2 位作者 郑屹 唐杨玉 郎丰铠 《遥感信息》 北大核心 2025年第2期149-158,共10页
煤火燃烧会造成温室效应加剧及煤炭资源浪费等问题,监测煤火发生趋势,实现精准的煤火区域探测具有重要意义。针对现有星载热红外数据空间分辨率较低,在小尺度煤火探测中受限及煤火区边缘探测不准确的问题,利用stacking集成学习降尺度方... 煤火燃烧会造成温室效应加剧及煤炭资源浪费等问题,监测煤火发生趋势,实现精准的煤火区域探测具有重要意义。针对现有星载热红外数据空间分辨率较低,在小尺度煤火探测中受限及煤火区边缘探测不准确的问题,利用stacking集成学习降尺度方法提高地表温度(land surface temperature,LST)数据分辨率,并结合孤立森林法探测煤火热异常区。首先将Landsat 8反演的100 m LST作为输入,以Sentinel-2计算的NDVI(normalized difference vegetation index)、MNDWI(modified normalized difference water index)、NDBI(normalized difference build-up index),结合DEM作为降尺度因子,利用stacking集成学习法降尺度得到10 m LST数据,并采用孤立森林法通过考虑温度与空间距离提取煤田热异常区。结果表明,降尺度后利于识别小范围的煤火,孤立森林法探测煤火区能有效减少误判,最终提高火区探测精度。 展开更多
关键词 降尺度 煤火 异常探测 地表温度 孤立森林法
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超声联合DSA引导下经上臂静脉输液港植入术在恶性肿瘤化疗患者中的临床应用研究 被引量:3
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作者 金光鑫 张芳琴 +3 位作者 王雅雯 郭艳 仇晓霞 张学彬 《介入放射学杂志》 CSCD 北大核心 2024年第7期733-737,共5页
目的 探讨超声联合DSA引导下经上臂静脉植入式输液港(TIVAP)作为恶性肿瘤患者化疗通路的安全性和有效性。方法 回顾性分析2020年1月至2022年1月上海交通大学医学院附属仁济医院1 546例接受经上臂TIVAP的恶性肿瘤患者临床资料,分析比较P... 目的 探讨超声联合DSA引导下经上臂静脉植入式输液港(TIVAP)作为恶性肿瘤患者化疗通路的安全性和有效性。方法 回顾性分析2020年1月至2022年1月上海交通大学医学院附属仁济医院1 546例接受经上臂TIVAP的恶性肿瘤患者临床资料,分析比较PICC置管室和DSA手术室实施该手术的植入成功率、一次置管成功率、手术时间和并发症率。结果 1 546例患者植入成功率100%,一次置管成功率99.48%;手术时间(22.7±3.1) min;总并发症率7.37%(114/1 546);置管室操作766例,DSA下操作780例,与置管室组比较,DSA组手术时间更短[(20.1±1.3) min vs (25.4±1.9) min],原发导管异位发生率更低(0%vs 0.78%),差异有统计学意义(P<0.05)。感染、血栓形成、上肢运动障碍、导管堵塞、港体外露、港体翻转等并发症两组间比较无统计学差异(P>0.05)。结论 超声引导下经上臂TIVAP对肿瘤化疗患者是一种安全有效的输液通路,联合术中DSA引导可减少手术时间,降低手术相关并发症率。 展开更多
关键词 超声 dsa引导 上臂静脉 输液港 并发症
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锰掺杂DSA电极及其对印染废水处理的过程优化
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作者 朱连燕 周幸福 《化工进展》 EI CAS CSCD 北大核心 2024年第6期3459-3467,共9页
以Ti/SnO_(2)-Sb形稳电极(DSA)为基底,采用浸渍法制备负载有活性层的Ti/SnO_(2)-Sb/SnO_(2)-Sb-Mn电极并进行了表征。利用box-behnken实验设计及响应曲面分析法,探讨槽压、搅拌速率、电极间距这三个因素对亚甲基蓝电催化脱色效率的影响... 以Ti/SnO_(2)-Sb形稳电极(DSA)为基底,采用浸渍法制备负载有活性层的Ti/SnO_(2)-Sb/SnO_(2)-Sb-Mn电极并进行了表征。利用box-behnken实验设计及响应曲面分析法,探讨槽压、搅拌速率、电极间距这三个因素对亚甲基蓝电催化脱色效率的影响,并建立相应的多元二次回归模型,方差分析结果表明,模型的拟合效果好,影响因素的显著性顺序依次为:槽压>电极间距>搅拌速率。验证实验结果显示,当槽压为4.8V、搅拌速率为320r/min、电极间距为1.5cm时,亚甲基蓝的脱色效果达到最佳,此时脱色率达到99.3%,模型的预测值非常接近实验值,验证了该方法的可行性和有效性,可为电催化脱色处理印染废水提供一定的技术指导。 展开更多
关键词 box-behnken响应曲面法 锰掺杂dsa电极 电催化氧化 脱色 印染废水
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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm 被引量:3
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作者 Guangbo Xu Bingting Zha +2 位作者 Hailu Yuan Zhen Zheng He Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期1-13,共13页
The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant ... The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering algorithm.This enhances the algorithm loading capability of the fuze.In order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)algorithm.We also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the fuze.Finally,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo signals.The experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance. 展开更多
关键词 Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm
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Product quality prediction based on RBF optimized by firefly algorithm 被引量:3
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作者 HAN Huihui WANG Jian +1 位作者 CHEN Sen YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期105-117,共13页
With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality pred... With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality prediction models have many disadvantages,such as high complexity and low accuracy.To overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data distribution.Then the RBFFALFM is used to predict product quality.Comprehensive expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality. 展开更多
关键词 product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm
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Optimization of jamming formation of USV offboard active decoy clusters based on an improved PSO algorithm 被引量:1
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作者 Zhaodong Wu Yasong Luo Shengliang Hu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期529-540,共12页
Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for t... Offboard active decoys(OADs)can effectively jam monopulse radars.However,for missiles approaching from a particular direction and distance,the OAD should be placed at a specific location,posing high requirements for timing and deployment.To improve the response speed and jamming effect,a cluster of OADs based on an unmanned surface vehicle(USV)is proposed.The formation of the cluster determines the effectiveness of jamming.First,based on the mechanism of OAD jamming,critical conditions are identified,and a method for assessing the jamming effect is proposed.Then,for the optimization of the cluster formation,a mathematical model is built,and a multi-tribe adaptive particle swarm optimization algorithm based on mutation strategy and Metropolis criterion(3M-APSO)is designed.Finally,the formation optimization problem is solved and analyzed using the 3M-APSO algorithm under specific scenarios.The results show that the improved algorithm has a faster convergence rate and superior performance as compared to the standard Adaptive-PSO algorithm.Compared with a single OAD,the optimal formation of USV-OAD cluster effectively fills the blind area and maximizes the use of jamming resources. 展开更多
关键词 Electronic countermeasure Offboard active decoy USV cluster Jamming formation optimization Improved PSO algorithm
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Novel method for extraction of ship target with overlaps in SAR image via EM algorithm 被引量:1
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作者 CAO Rui WANG Yong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期874-887,共14页
The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition... The quality of synthetic aperture radar(SAR)image degrades in the case of multiple imaging projection planes(IPPs)and multiple overlapping ship targets,and then the performance of target classification and recognition can be influenced.For addressing this issue,a method for extracting ship targets with overlaps via the expectation maximization(EM)algorithm is pro-posed.First,the scatterers of ship targets are obtained via the target detection technique.Then,the EM algorithm is applied to extract the scatterers of a single ship target with a single IPP.Afterwards,a novel image amplitude estimation approach is pro-posed,with which the radar image of a single target with a sin-gle IPP can be generated.The proposed method can accom-plish IPP selection and targets separation in the image domain,which can improve the image quality and reserve the target information most possibly.Results of simulated and real mea-sured data demonstrate the effectiveness of the proposed method. 展开更多
关键词 expectation maximization(EM)algorithm image processing imaging projection plane(IPP) overlapping ship tar-get synthetic aperture radar(SAR)
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Topological optimization of ballistic protective structures through genetic algorithms in a vulnerability-driven environment
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作者 Salvatore Annunziata Luca Lomazzi +1 位作者 Marco Giglio Andrea Manes 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期125-137,共13页
Reducing the vulnerability of a platform,i.e.,the risk of being affected by hostile objects,is of paramount importance in the design process of vehicles,especially aircraft.A simple and effective way to decrease vulne... Reducing the vulnerability of a platform,i.e.,the risk of being affected by hostile objects,is of paramount importance in the design process of vehicles,especially aircraft.A simple and effective way to decrease vulnerability is to introduce protective structures to intercept and possibly stop threats.However,this type of solution can lead to a significant increase in weight,affecting the performance of the aircraft.For this reason,it is crucial to study possible solutions that allow reducing the vulnerability of the aircraft while containing the increase in structural weight.One possible strategy is to optimize the topology of protective solutions to find the optimal balance between vulnerability and the weight of the added structures.Among the many optimization techniques available in the literature for this purpose,multiobjective genetic algorithms stand out as promising tools.In this context,this work proposes the use of a in-house software for vulnerability calculation to guide the process of topology optimization through multi-objective genetic algorithms,aiming to simultaneously minimize the weight of protective structures and vulnerability.In addition to the use of the in-house software,which itself represents a novelty in the field of topology optimization of structures,the method incorporates a custom mutation function within the genetic algorithm,specifically developed using a graph-based approach to ensure the continuity of the generated structures.The tool developed for this work is capable of generating protections with optimized layouts considering two different types of impacting objects,namely bullets and fragments from detonating objects.The software outputs a set of non-dominated solutions describing different topologies that the user can choose from. 展开更多
关键词 Topological optimization Protective structure Genetic algorithm SURVIVABILITY VULNERABILITY
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Research on User Profile Construction Method Based on Improved TF-IDF Algorithm
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作者 SHAO Ze-ming LI Yu-ang +4 位作者 YANG Ke WANG Guo-peng LIU Xing-guo CHEN Han-ning SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第6期110-116,共7页
In the data-driven era of the internet and business environments,constructing accurate user profiles is paramount for personalized user understanding and classification.The traditional TF-IDF algorithm has some limita... In the data-driven era of the internet and business environments,constructing accurate user profiles is paramount for personalized user understanding and classification.The traditional TF-IDF algorithm has some limitations when evaluating the impact of words on classification results.Consequently,an improved TF-IDF-K algorithm was introduced in this study,which included an equalization factor,aimed at constructing user profiles by processing and analyzing user search records.Through the training and prediction capabilities of a Support Vector Machine(SVM),it enabled the prediction of user demographic attributes.The experimental results demonstrated that the TF-IDF-K algorithm has achieved a significant improvement in classification accuracy and reliability. 展开更多
关键词 TF-IDF-K algorithm User profiling Equalization factor SVM
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