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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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偏高岭土对聚合物改性PC-CSA-FGD防腐砂浆性能的影响
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作者 许慧杰 张国防 +1 位作者 罗顺 张震雷 《建筑材料学报》 北大核心 2025年第4期358-366,共9页
本文研究了偏高岭土(MK)对聚合物改性硅酸盐水泥-硫铝酸盐水泥-脱硫石膏(PC-CSA-FGD)三元胶凝体系防腐砂浆(简称防腐砂浆)凝结时间、力学性能、抗硫酸盐侵蚀性能、抗氯离子侵蚀性能、水化产物和孔结构的影响.结果表明:随着MK掺量的增大... 本文研究了偏高岭土(MK)对聚合物改性硅酸盐水泥-硫铝酸盐水泥-脱硫石膏(PC-CSA-FGD)三元胶凝体系防腐砂浆(简称防腐砂浆)凝结时间、力学性能、抗硫酸盐侵蚀性能、抗氯离子侵蚀性能、水化产物和孔结构的影响.结果表明:随着MK掺量的增大,防腐砂浆的凝结时间逐渐缩短,掺30%MK防腐砂浆的初凝时间和终凝时间较初始值分别缩短了28、47 min;当掺量较低时,MK能提高防腐砂浆的力学性能、抗硫酸盐侵蚀性能和抗氯离子侵蚀性能,掺10%MK防腐砂浆的90 d抗折强度和抗压强度分别为13.6、73.4 MPa,氯离子扩散系数仅为0.30×10^(-12)m^(2)/s,这与MK能优化孔结构、降低水化产物氢氧化钙和钙矾石含量、反应生成更多水化硅酸钙凝胶和水化硅铝酸钙凝胶有关;MK在防腐砂浆中的掺量不宜超过20%,以10%最佳. 展开更多
关键词 防腐砂浆 硅酸盐水泥-硫铝酸盐水泥-脱硫石膏三元胶凝体系 偏高岭土 物理力学性能 抗硫酸盐侵蚀性能 抗氯离子侵蚀性能
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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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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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基于INGO-CSA-LSTMN的变转速齿轮故障智能识别方法
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作者 陈向民 李博 +3 位作者 张亢 姚鹏 李泳辉 雷瀚霖 《动力工程学报》 北大核心 2025年第6期913-923,共11页
为提高齿轮在变转速工况下的故障识别效率和准确率,提出了一种基于改进北方苍鹰优化(improved northern goshawk optimization,INGO)算法优化卷积自注意力长短期记忆网络(convolutional self-attention long short-term memory network,... 为提高齿轮在变转速工况下的故障识别效率和准确率,提出了一种基于改进北方苍鹰优化(improved northern goshawk optimization,INGO)算法优化卷积自注意力长短期记忆网络(convolutional self-attention long short-term memory network,CSA-LSTMN)的变转速齿轮故障智能识别方法,即INGO-CSA-LSTMN。针对传统北方苍鹰优化算法训练时间过长和容易陷入局部最优的问题,引入正弦脉冲调制混沌映射和随机莱维飞行策略,提出一种INGO算法,并将其应用于所构建的CSA-LSTMN模型的关键参数寻优,以提高该模型的稳定性及训练效率。通过测试函数的检验表明:INGO算法具有更快的收敛速度,可更准确地找到最优解。通过2种不同试验台齿轮数据集的分析表明:相较于其他常用网络模型,INGO-CSA-LSTMN模型对于不同工况下的齿轮故障具有更高的识别精度,准确率均在99.9%以上。 展开更多
关键词 变转速工况 齿轮 北方苍鹰优化算法 卷积自注意力长短期记忆网 智能诊断
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基于CSA-PLS算法的养殖水体水质快速高光谱预测反演模型研究 被引量:3
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作者 马启良 刘梅 +2 位作者 祁亨年 杨小明 原居林 《海洋与湖沼》 CAS CSCD 北大核心 2024年第2期375-385,共11页
养殖水体水质的优劣直接影响养殖对象的成长,准确、快速、全面地掌控养殖水环境的水质参数变化情况具有重要意义。传统的水质指标监测方法都通过人工采样的方式,不仅耗费时间长,且只能体现局部水体情况。针对这些问题,提出了一种乌鸦搜... 养殖水体水质的优劣直接影响养殖对象的成长,准确、快速、全面地掌控养殖水环境的水质参数变化情况具有重要意义。传统的水质指标监测方法都通过人工采样的方式,不仅耗费时间长,且只能体现局部水体情况。针对这些问题,提出了一种乌鸦搜索算法(CSA)结合偏最小二乘回归(PLSR)的高光谱特征波段筛选方法,快速构建回归模型,实现光谱数据的精准预测反演。以连片的养殖小区为研究对象,采集养殖水体样本并拍摄同时期的高光谱影像数据。首先对提取的采样点光谱数据利用多种数据变换方法分别预处理;其次利用这些数据,对水质指标总氮(TN)、氨氮(NH_(4)^(+)-N)、总磷(TP)和化学需氧量(COD)分别构建全波段的SVR和AdaBoost回归模型,同时与提出的CSA-PLS自动筛选波段方法和传统的连续投影算法(SPA)筛选波段后构建的模型进行比较分析;最后根据决定系数(R^(2))和均方根误差(REMS)选出适合各水质指标的最优模型。从实验结果可以看出,所提波段筛选方法的AdaBoost模型预测结果优于SVR和传统SPA方法提取特征波段后构建的模型,与全波段最优模型相比,在评价指标R^(2)和RMSE上TN提升了18.32%和10.73%;NH_(4)^(+)-N提升了17.42%和11.19%;COD提升了2.15%和2.54%。结果表明,基于CSA-PLS算法的光谱波段自动筛选方法结合AdaBoost构建的预测反演模型是有效、可行的,具有较高的精准度,为实现养殖水环境实时准确的预警调控提供了一种新的数据预测模型。 展开更多
关键词 高光谱数据 水质预测 乌鸦搜索算法 养殖水环境 集成学习
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融合NSGA-II和CSA的多目标车间调度 被引量:4
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作者 杨青 席珍珍 +2 位作者 葛亮 林星宇 邢志超 《计算机工程与应用》 CSCD 北大核心 2024年第4期315-323,共9页
针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-do... 针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-dominated sorting genetic algorithms)和克隆选择(clonal selection algorithm,CSA)的改进算法INGCSA来解决此类问题。采用工件、加工机台和AGV三部分编码;引入非支配排序和目标函数值大小排序后总得分进行种群分层,从而有效地保留优秀个体;针对克隆后的种群,对不同等级的种群采取不同的变异概率,并对染色体进行内部交换与均匀交叉混合交换的基因重组,有效地提高了种群的多样性与防止陷入局部最优。通过三组对比实验,验证了该算法在探索最优解时,具有运行时间短、稳定性高和收敛性好等优点。 展开更多
关键词 NSGA-II 克隆选择算法 任务调度 运输调度 自动引导车(AGV)
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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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社区支持农业情境下亲子研学动机对CSA产品消费意愿影响机制研究
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作者 闫晓莹 刘保庵 尹青青 《安徽农业科学》 CAS 2024年第15期146-151,共6页
基于广州和深圳两市447份亲子家庭问卷数据,构建中介效应模型并予以验证,结果显示:CSA课程需求、社交需求均正向影响CSA产品消费意愿。进一步分析表明:亲子研学活动参与意愿在CSA课程需求及社交需求对CSA产品消费意愿的影响机制中均起... 基于广州和深圳两市447份亲子家庭问卷数据,构建中介效应模型并予以验证,结果显示:CSA课程需求、社交需求均正向影响CSA产品消费意愿。进一步分析表明:亲子研学活动参与意愿在CSA课程需求及社交需求对CSA产品消费意愿的影响机制中均起部分中介作用。兼顾CSA课程需求、社交需求的农场亲子研学活动可成为连接CSA城乡交流、提升CSA产品消费意愿的有效载体。 展开更多
关键词 社区支持农业 csa课程需求 社交需求 亲子研学活动参与意愿 消费意愿
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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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基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断
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作者 戚晓利 王兆俊 +3 位作者 毛俊懿 王志文 崔德海 赵方祥 《振动与冲击》 EI CSCD 北大核心 2024年第11期165-175,共11页
针对现有深度卷积神经网络对滚动轴承混合故障诊断效果不佳以及模型复杂度过高导致计算成本过大等问题,提出了一种基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断方法。该模型由RegNet-CSAM网络和ZOA-KELM分类算法组成。首先,将融合... 针对现有深度卷积神经网络对滚动轴承混合故障诊断效果不佳以及模型复杂度过高导致计算成本过大等问题,提出了一种基于RegNet-CSAM与ZOA-KELM模型的滚动轴承故障诊断方法。该模型由RegNet-CSAM网络和ZOA-KELM分类算法组成。首先,将融合了通道和空间特征的注意力机制CSAM与组卷积残差模块结合,提升该结构的表征能力,由此构建的RegNet-CSAM网络,模型复杂度为0.48GF;其次,在分类阶段将斑马优化核极限学习机(ZOA-KELM)替代原来网络中使用的Softmax函数完成最后的分类任务。滚动轴承故障诊断试验结果表明,RegNet网络对滚动轴承混合故障样本容易产生误判,CSAM的融入虽将RegNet网络的分类精度进一步提高,但是仍然存在一定程度的滚动轴承混合故障误判问题;而将ZOA-KELM替代Softmax函数后再对RegNet-CSAM网络输出特征进行分类,能够有效识别出滚动轴承的单一和混合故障,准确率达到了99.92%。所提方法对比其他网络,诊断精度最大提升5.02%,模型复杂度最大缩减32倍。 展开更多
关键词 故障诊断 滚动轴承 组卷积残差结构 注意力机制 斑马优化核极限学习机(ZOA-KELM)
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基于CSA-AFSA算法的集装箱港口连续型泊位分配优化
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作者 初良勇 章嘉文 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第10期61-69,共9页
为提升集装箱港口运营效率,笔者研究了考虑潮汐因素与泊位偏好的连续型泊位分配问题。引入了船舶时空矩形不可重叠约束和潮汐时间窗约束,构建以最小化船舶等待、延迟离港、泊位偏离以及在港期间油耗费用和最小为目标的混合整数线性规划... 为提升集装箱港口运营效率,笔者研究了考虑潮汐因素与泊位偏好的连续型泊位分配问题。引入了船舶时空矩形不可重叠约束和潮汐时间窗约束,构建以最小化船舶等待、延迟离港、泊位偏离以及在港期间油耗费用和最小为目标的混合整数线性规划模型;根据模型特征,采用CPLEX求解软件、鱼群算法、布谷鸟搜索算法和布谷鸟鱼群混合算法进行求解,以计划周期为36 h的20个不同规模的船舶到港数据为研究算例,通过算例求解得到符和潮汐时间窗、泊位偏好等要求的泊位分配方案。算例求解表明:算例规模较小时,CPLEX可以在较短时间内求出最优泊位分配方案;算例规模较大时,CPLEX求解时间较长,布谷鸟鱼群混合算法可以在平均3 min内求出与CPLEX差距为0.39%~4.20%的次优解;不同算法间的对比表明,布谷鸟鱼群混合算法求解能力更优,混合算法所得泊位分配方案中,乘潮船舶的进出港时刻均在潮汐高水位时段,且85%以上的船舶在偏好泊靠点200 m内接受装卸服务。 展开更多
关键词 港口与航道工程 布谷鸟鱼群混合算法 连续型泊位分配 混合整数线性规划模型 潮汐因素 泊位偏好
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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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