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A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability
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作者 Jingyu Wang Ping Jiang Jianjun Qi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1889-1918,共30页
The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the... The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV swarm.Due to the high cost and long duration of operational tests,it is essential to plan the test in advance.To solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission reliability.Therefore,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test plans.This study first constructs a mission reliability model for the UAV swarm in the combat stage.Then,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability model.Finally,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the model.The optimal plans considering both reliability and cost are obtained.The proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning. 展开更多
关键词 UAV swarm PMS MOQPSO BDD mission reliability operational test planning
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True-temperature inversion algorithm for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization
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作者 Mei Liang Zhuo Sun +3 位作者 Jiasong Liu Yongsheng Wang Lei Liang Long Zhang 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期55-62,共8页
Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difficult inversion problems with unknown emissivity.Fractional-order... Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difficult inversion problems with unknown emissivity.Fractional-order calculus has the inherent advantage of easily jumping out of local extreme values;here,it is introduced into the particle-swarm algorithm to invert the true temperature.An improved adaptive-adjustment mechanism is applied to automatically adjust the current velocity order of the particles and update their velocity and position values,increasing the accuracy of the true temperature values.The results of simulations using the proposed algorithm were compared with three algorithms using typical emissivity models:the internal penalty function algorithm,the optimization function(fmincon)algorithm,and the conventional particle-swarm optimization algorithm.The results show that the proposed algorithm has good accuracy for true-temperature inversion.Actual experimental results from a rocket-motor plume were used to demonstrate that the true-temperature inversion results of this algorithm are in good agreement with the theoretical true-temperature values. 展开更多
关键词 Fractional-order particle swarm True-temperature inversion algorithm Multi-wavelength pyrometer
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Using Improved Particle Swarm Optimization Algorithm for Location Problem of Drone Logistics Hub
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作者 Li Zheng Gang Xu Wenbin Chen 《Computers, Materials & Continua》 SCIE EI 2024年第1期935-957,共23页
Drone logistics is a novel method of distribution that will become prevalent.The advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for ... Drone logistics is a novel method of distribution that will become prevalent.The advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for the company’s transportation operations.Logistics firms must discern the ideal location for establishing a logistics hub,which is challenging due to the simplicity of existing models and the intricate delivery factors.To simulate the drone logistics environment,this study presents a new mathematical model.The model not only retains the aspects of the current models,but also considers the degree of transportation difficulty from the logistics hub to the village,the capacity of drones for transportation,and the distribution of logistics hub locations.Moreover,this paper proposes an improved particle swarm optimization(PSO)algorithm which is a diversity-based hybrid PSO(DHPSO)algorithm to solve this model.In DHPSO,the Gaussian random walk can enhance global search in the model space,while the bubble-net attacking strategy can speed convergence.Besides,Archimedes spiral strategy is employed to overcome the local optima trap in the model and improve the exploitation of the algorithm.DHPSO maintains a balance between exploration and exploitation while better defining the distribution of logistics hub locations Numerical experiments show that the newly proposed model always achieves better locations than the current model.Comparing DHPSO with other state-of-the-art intelligent algorithms,the efficiency of the scheme can be improved by 42.58%.This means that logistics companies can reduce distribution costs and consumers can enjoy a more enjoyable shopping experience by using DHPSO’s location selection.All the results show the location of the drone logistics hub is solved by DHPSO effectively. 展开更多
关键词 Drone logistics location problem mathematical model DIVERSITY particle swarm optimization
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Synergistic Swarm Optimization Algorithm
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作者 Sharaf Alzoubi Laith Abualigah +3 位作者 Mohamed Sharaf Mohammad Sh.Daoud Nima Khodadadi Heming Jia 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2557-2604,共48页
This research paper presents a novel optimization method called the Synergistic Swarm Optimization Algorithm(SSOA).The SSOA combines the principles of swarmintelligence and synergistic cooperation to search for optima... This research paper presents a novel optimization method called the Synergistic Swarm Optimization Algorithm(SSOA).The SSOA combines the principles of swarmintelligence and synergistic cooperation to search for optimal solutions efficiently.A synergistic cooperation mechanism is employed,where particles exchange information and learn from each other to improve their search behaviors.This cooperation enhances the exploitation of promising regions in the search space while maintaining exploration capabilities.Furthermore,adaptive mechanisms,such as dynamic parameter adjustment and diversification strategies,are incorporated to balance exploration and exploitation.By leveraging the collaborative nature of swarm intelligence and integrating synergistic cooperation,the SSOAmethod aims to achieve superior convergence speed and solution quality performance compared to other optimization algorithms.The effectiveness of the proposed SSOA is investigated in solving the 23 benchmark functions and various engineering design problems.The experimental results highlight the effectiveness and potential of the SSOA method in addressing challenging optimization problems,making it a promising tool for a wide range of applications in engineering and beyond.Matlab codes of SSOA are available at:https://www.mathworks.com/matlabcentral/fileexchange/153466-synergistic-swarm-optimization-algorithm. 展开更多
关键词 Synergistic swarm optimization algorithm optimization algorithm METAHEURISTIC engineering problems benchmark functions
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Revolutionary entrapment model of uniformly distributed swarm robots in morphogenetic formation
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作者 Chen Wang Zhaohui Shi +3 位作者 Minqiang Gu Weicheng Luo Xiaomin Zhu Zhun Fan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期496-509,共14页
This study proposes a method for uniformly revolving swarm robots to entrap multiple targets,which is based on a gene regulatory network,an adaptive decision mechanism,and an improved Vicsek-model.Using the gene regul... This study proposes a method for uniformly revolving swarm robots to entrap multiple targets,which is based on a gene regulatory network,an adaptive decision mechanism,and an improved Vicsek-model.Using the gene regulatory network method,the robots can generate entrapping patterns according to the environmental input,including the positions of the targets and obstacles.Next,an adaptive decision mechanism is proposed,allowing each robot to choose the most well-adapted capture point on the pattern,based on its environment.The robots employ an improved Vicsek-model to maneuver to the planned capture point smoothly,without colliding with other robots or obstacles.The proposed decision mechanism,combined with the improved Vicsek-model,can form a uniform entrapment shape and create a revolving effect around targets while entrapping them.This study also enables swarm robots,with an adaptive pattern formation,to entrap multiple targets in complex environments.Swarm robots can be deployed in the military field of unmanned aerial vehicles’(UAVs)entrapping multiple targets.Simulation experiments demonstrate the feasibility and superiority of the proposed gene regulatory network method. 展开更多
关键词 swarm intelligence Revolutionary entrapment FLOCKING ROBOTS Gene regulatory network Vicsek-model Entrapping multiple targets
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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Xu Yang Ruiqing Sun Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1342-1357,共16页
Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.... Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed. 展开更多
关键词 Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.
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Identifying influential spreaders in social networks: A two-stage quantum-behaved particle swarm optimization with Lévy flight
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作者 卢鹏丽 揽继茂 +3 位作者 唐建新 张莉 宋仕辉 朱虹羽 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期743-754,共12页
The influence maximization problem aims to select a small set of influential nodes, termed a seed set, to maximize their influence coverage in social networks. Although the methods that are based on a greedy strategy ... The influence maximization problem aims to select a small set of influential nodes, termed a seed set, to maximize their influence coverage in social networks. Although the methods that are based on a greedy strategy can obtain good accuracy, they come at the cost of enormous computational time, and are therefore not applicable to practical scenarios in large-scale networks. In addition, the centrality heuristic algorithms that are based on network topology can be completed in relatively less time. However, they tend to fail to achieve satisfactory results because of drawbacks such as overlapped influence spread. In this work, we propose a discrete two-stage metaheuristic optimization combining quantum-behaved particle swarm optimization with Lévy flight to identify a set of the most influential spreaders. According to the framework,first, the particles in the population are tasked to conduct an exploration in the global solution space to eventually converge to an acceptable solution through the crossover and replacement operations. Second, the Lévy flight mechanism is used to perform a wandering walk on the optimal candidate solution in the population to exploit the potentially unidentified influential nodes in the network. Experiments on six real-world social networks show that the proposed algorithm achieves more satisfactory results when compared to other well-known algorithms. 展开更多
关键词 social networks influence maximization metaheuristic optimization quantum-behaved particle swarm optimization Lévy flight
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Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques
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作者 ZHAO Haijun WEI Aihua +3 位作者 MA Fengshan DAI Fenggang JIANG Yongbing LI Hui 《Journal of Mountain Science》 SCIE CSCD 2024年第2期397-412,共16页
The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques we... The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility results.In this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning algorithms.In total,133 historical debris flow records and 16 related factors were selected.The support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step process.First,the particle swarm optimization(PSO)algorithm was employed to select the SVM model hyperparameters.Second,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,respectively.Three statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the models.The results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM models.Moreover,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing processes.It was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment results.Moreover,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning algorithms.The high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intensive human activities and heavy rainfall events. 展开更多
关键词 Chengde Feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility
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Hybrid Hierarchical Particle Swarm Optimization with Evolutionary Artificial Bee Colony Algorithm for Task Scheduling in Cloud Computing
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作者 Shasha Zhao Huanwen Yan +3 位作者 Qifeng Lin Xiangnan Feng He Chen Dengyin Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1135-1156,共22页
Task scheduling plays a key role in effectively managing and allocating computing resources to meet various computing tasks in a cloud computing environment.Short execution time and low load imbalance may be the chall... Task scheduling plays a key role in effectively managing and allocating computing resources to meet various computing tasks in a cloud computing environment.Short execution time and low load imbalance may be the challenges for some algorithms in resource scheduling scenarios.In this work,the Hierarchical Particle Swarm Optimization-Evolutionary Artificial Bee Colony Algorithm(HPSO-EABC)has been proposed,which hybrids our presented Evolutionary Artificial Bee Colony(EABC),and Hierarchical Particle Swarm Optimization(HPSO)algorithm.The HPSO-EABC algorithm incorporates both the advantages of the HPSO and the EABC algorithm.Comprehensive testing including evaluations of algorithm convergence speed,resource execution time,load balancing,and operational costs has been done.The results indicate that the EABC algorithm exhibits greater parallelism compared to the Artificial Bee Colony algorithm.Compared with the Particle Swarm Optimization algorithm,the HPSO algorithmnot only improves the global search capability but also effectively mitigates getting stuck in local optima.As a result,the hybrid HPSO-EABC algorithm demonstrates significant improvements in terms of stability and convergence speed.Moreover,it exhibits enhanced resource scheduling performance in both homogeneous and heterogeneous environments,effectively reducing execution time and cost,which also is verified by the ablation experimental. 展开更多
关键词 Cloud computing distributed processing evolutionary artificial bee colony algorithm hierarchical particle swarm optimization load balancing
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Optimal Configuration of Fault Location Measurement Points in DC Distribution Networks Based on Improved Particle Swarm Optimization Algorithm
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作者 Huanan Yu Hangyu Li +1 位作者 He Wang Shiqiang Li 《Energy Engineering》 EI 2024年第6期1535-1555,共21页
The escalating deployment of distributed power sources and random loads in DC distribution networks hasamplified the potential consequences of faults if left uncontrolled. To expedite the process of achieving an optim... The escalating deployment of distributed power sources and random loads in DC distribution networks hasamplified the potential consequences of faults if left uncontrolled. To expedite the process of achieving an optimalconfiguration of measurement points, this paper presents an optimal configuration scheme for fault locationmeasurement points in DC distribution networks based on an improved particle swarm optimization algorithm.Initially, a measurement point distribution optimization model is formulated, leveraging compressive sensing.The model aims to achieve the minimum number of measurement points while attaining the best compressivesensing reconstruction effect. It incorporates constraints from the compressive sensing algorithm and networkwide viewability. Subsequently, the traditional particle swarm algorithm is enhanced by utilizing the Haltonsequence for population initialization, generating uniformly distributed individuals. This enhancement reducesindividual search blindness and overlap probability, thereby promoting population diversity. Furthermore, anadaptive t-distribution perturbation strategy is introduced during the particle update process to enhance the globalsearch capability and search speed. The established model for the optimal configuration of measurement points issolved, and the results demonstrate the efficacy and practicality of the proposed method. The optimal configurationreduces the number of measurement points, enhances localization accuracy, and improves the convergence speedof the algorithm. These findings validate the effectiveness and utility of the proposed approach. 展开更多
关键词 Optimal allocation improved particle swarm algorithm fault location compressed sensing DC distribution network
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Track correlation algorithm based on CNN-LSTM for swarm targets
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作者 CHEN Jinyang WANG Xuhua CHEN Xian 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期417-429,共13页
The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms... The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for correlation.In this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm targets.Precisely, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets. 展开更多
关键词 track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network
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Particle Swarm Optimization-Based Hyperparameters Tuning of Machine Learning Models for Big COVID-19 Data Analysis
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作者 Hend S. Salem Mohamed A. Mead Ghada S. El-Taweel 《Journal of Computer and Communications》 2024年第3期160-183,共24页
Analyzing big data, especially medical data, helps to provide good health care to patients and face the risks of death. The COVID-19 pandemic has had a significant impact on public health worldwide, emphasizing the ne... Analyzing big data, especially medical data, helps to provide good health care to patients and face the risks of death. The COVID-19 pandemic has had a significant impact on public health worldwide, emphasizing the need for effective risk prediction models. Machine learning (ML) techniques have shown promise in analyzing complex data patterns and predicting disease outcomes. The accuracy of these techniques is greatly affected by changing their parameters. Hyperparameter optimization plays a crucial role in improving model performance. In this work, the Particle Swarm Optimization (PSO) algorithm was used to effectively search the hyperparameter space and improve the predictive power of the machine learning models by identifying the optimal hyperparameters that can provide the highest accuracy. A dataset with a variety of clinical and epidemiological characteristics linked to COVID-19 cases was used in this study. Various machine learning models, including Random Forests, Decision Trees, Support Vector Machines, and Neural Networks, were utilized to capture the complex relationships present in the data. To evaluate the predictive performance of the models, the accuracy metric was employed. The experimental findings showed that the suggested method of estimating COVID-19 risk is effective. When compared to baseline models, the optimized machine learning models performed better and produced better results. 展开更多
关键词 Big COVID-19 Data Machine Learning Hyperparameter Optimization Particle swarm Optimization Computational Intelligence
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SWARM卫星时变重力场反演及其精度
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作者 杜向锋 魏德宏 《大地测量与地球动力学》 CSCD 北大核心 2023年第12期1240-1245,共6页
基于SWARM卫星的精密轨道数据,利用短弧积分法解算2015-01~2021-12共84个月的40阶次TVG-SWARM月时变重力场模型,并与ASU、COST-G、IGG和ITSG等机构的月时变重力场模型进行比较。结果表明:1)从大地水准面阶误差与模型位系数误差谱看,不同... 基于SWARM卫星的精密轨道数据,利用短弧积分法解算2015-01~2021-12共84个月的40阶次TVG-SWARM月时变重力场模型,并与ASU、COST-G、IGG和ITSG等机构的月时变重力场模型进行比较。结果表明:1)从大地水准面阶误差与模型位系数误差谱看,不同SWARM模型的低阶位系数精度相当,特别是前10阶均与ITSG-GRACE/GRACE-FO接近;2)不同SWARM模型与ITSG-GRACE/GRACE-FO模型全球陆地水储量变化趋势空间分布具有较好的一致性,在亚马孙流域、格陵兰岛、密西西比河流域和西西伯利亚等区域,TVG-SWARM与ITSG-GRACE/GRACE-FO模型的趋势差值分别为0.23 cm/a、0.27 cm/a、0.57 cm/a和0.47 cm/a,相关系数均达到0.85以上,并与IGG-SWARM模型结果最为接近。本文研究结果证明了TVG-SWARM模型精度可靠,可以用于监测大尺度陆地水储量变化。 展开更多
关键词 swarm卫星 时变重力场 陆地水储量变化 精度分析
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基于SWARM智能无人蜂群自组织作战行为模式仿真研究
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作者 李志强 李元龙 +1 位作者 刘经德 殷来祥 《火力与指挥控制》 CSCD 北大核心 2023年第11期145-151,共7页
智能无人蜂群作战以其低成本、大规模协同作战能力优势必将成为未来智能化战争的重要作战样式。根据智能无人蜂群作战系统组成结构和作战特点,以复杂系统自组织理论为基础,基于自底向上的自组织涌现性建模方法,在复杂系统Swarm建模仿真... 智能无人蜂群作战以其低成本、大规模协同作战能力优势必将成为未来智能化战争的重要作战样式。根据智能无人蜂群作战系统组成结构和作战特点,以复杂系统自组织理论为基础,基于自底向上的自组织涌现性建模方法,在复杂系统Swarm建模仿真平台上构建具有有限行为能力和局部交互规则的智能无人蜂群个体模型,通过仿真实验,探索研究无人蜂群作战系统宏观整体群体智能作战行为模式和作战能力与其微观组成个体行为规则的关系,为智能无人蜂群作战系统个体作战行为规则、宏观整体作战行为模式产生机制和作战能力研究提供借鉴与参考。 展开更多
关键词 无人蜂群 自组织 涌现性 作战实验
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SWARM监测松辽流域陆地水储量变化的适用性分析
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作者 孙炜程 魏德宏 +2 位作者 罗朱键 禤键豪 张兴福 《测绘通报》 CSCD 北大核心 2023年第11期107-111,共5页
针对GRACE与GRACE-FO卫星存在衔接空白且卫星加速度计已出现受损的情况,SWARM卫星监测可作为一种有效补充的技术手段。本文选择ASU、IGG和COST-G等机构的SWARM时变模型监测松辽流域陆地水储量变化,并与GRACE、GRACE-FO时变模型进行比较... 针对GRACE与GRACE-FO卫星存在衔接空白且卫星加速度计已出现受损的情况,SWARM卫星监测可作为一种有效补充的技术手段。本文选择ASU、IGG和COST-G等机构的SWARM时变模型监测松辽流域陆地水储量变化,并与GRACE、GRACE-FO时变模型进行比较。结果表明:①各SWARM时变模型的前10阶位系数与GRACE模型精度接近,其中IGG-SWARM模型经1200 km高斯滤波后的信噪比,相较于ASU和COST-G模型分别高62.47%、55.99%;②IGG-SWARM时变模型可探测松辽流域大尺度陆地水储量的时空变化特征,识别流域内的显著旱涝事件,与GRACE、GRACE-FO时变模型均反映出松辽流域在2015年7月—2020年12月的陆地水储量整体呈上升趋势,两者在数据重叠时段的相关系数可达0.6以上。因此,SWARM时变模型可适用于监测松辽流域的陆地水储量变化研究。 展开更多
关键词 swarm GRACE GRACE-FO 松辽流域 陆地水储量
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Swarm卫星星载接收机GPS信号中断统计特征分析
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作者 胡洋 熊超 +6 位作者 尹凡 万欣 郑宇豪 黄宇阳 刘裔文 朱艺洵 王丰珏 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2023年第11期4464-4477,共14页
本文聚焦于欧空局Swarm卫星星载接收机在中纬地区出现的GPS信号中断事件,利用其近9年(2014年1月至2022年9月)的观测数据,详细统计了GPS信号中断事件发生的时空分布特征及与背景等离子体密度起伏的关系.研究结果表明Swarm卫星在其接收机... 本文聚焦于欧空局Swarm卫星星载接收机在中纬地区出现的GPS信号中断事件,利用其近9年(2014年1月至2022年9月)的观测数据,详细统计了GPS信号中断事件发生的时空分布特征及与背景等离子体密度起伏的关系.研究结果表明Swarm卫星在其接收机锁相环带宽从0.75 Hz调整至1.0 Hz前后,GPS信号中断事件表现出不同的时空分布特征.在前一个时期,2014年1月1日至2016年8月11日,GPS信号中断事件主要分布在低纬磁赤道附近和高纬极区附近,少量中断事件分布在中国东部地区;而在后一个时期,2016年8月12日至2022年9月30日,GPS信号中断事件则出现在了所有的纬度,同时表现出显著的经度差异.前一个时期内GPS信号中断事件表现出了明显的季节依赖,而后一个时期内出现的GPS信号中断事件则出现了无季节特性的弥散状分布.该结果表明当Swarm星载接收机锁相环带宽调整至1.0 Hz时,虽然提升了其应对电离层闪烁条件下多普勒频移的动态调整范围,但同时也增加了接收机载波相位观测的热噪声,进而导致接收机产生了一些随机的短时信号中断.除了上述不同,两个时期内的GPS信号中断事件也表现出了一些共同特征,比如信号中断事件主要均集中在GPS卫星相对于Swarm处于较低仰角(<20°)的情况下;同时这些事件主要发生在发射较早的BlockⅡR和BlockⅡA类型GPS卫星上,暗示了随着发射年限的增加与星载设备的老化,GPS卫星的稳定性会逐渐降低.通过进一步对比分析Swarm卫星出现与未出现GPS信号中断轨道对应的原位电子密度观测数据,发现GPS信号中断的轨道其对应的电子密度波动更剧烈,表明背景等离子体密度的梯度强度是引起Swarm星载接收机在中纬地区出现GPS信号中断的重要原因.本文的研究结果对于星载接收机的设计优化,特别是提升其在电离层闪烁条件下的稳定性有重要的参考意义. 展开更多
关键词 swarm卫星 星载GPS信号中断 接收机锁相环带宽 背景电子密度起伏
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基于Swarm卫星数据及CHAOS-6模型的中国地区岩石圈磁场研究
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作者 姜乙 Richard Holme 蒋勇 《Applied Geophysics》 SCIE CSCD 2023年第4期422-431,669,670,共12页
本研究主要关注Swarm卫星数据及CHAOS-6模型对岩石圈磁场的应用。重点考察该模型能否较好地模拟中国地区岩石圈磁场,同时检验高质量的卫星数据中是否还包含模型模拟部分以外的其他信息,特别是岩石圈磁场中的一些小尺度特征,这些信息有... 本研究主要关注Swarm卫星数据及CHAOS-6模型对岩石圈磁场的应用。重点考察该模型能否较好地模拟中国地区岩石圈磁场,同时检验高质量的卫星数据中是否还包含模型模拟部分以外的其他信息,特别是岩石圈磁场中的一些小尺度特征,这些信息有助于研究岩石圈磁场并提高模型的精度。基于Swarm卫星数据和CHAOS-6模型,将卫星数据沿轨道按纬度1^°为间隔网格化后,计算相邻网格的差值,即差分计算。对比不同轨道,不同时间段之间的轨道差分,同时还考虑模型中15-20阶磁场的长期变化,以研究岩石圈磁场中所包含的小尺度成分。结果显示CHAOS-6模型可以很好地模拟Swarm卫星数据,均方偏差在3nT左右,模型基本反映了地磁场的长期变化。此外,从数据上还发现了一个未被模拟的磁异常,该异常位于磁赤道附近,有可能是外源场影响的结果。对于岩石圈磁场的研究应更侧重于所建立的模型而非卫星数据本身。 展开更多
关键词 地磁场 swarm卫星任务 岩石圈磁场 CHAOS-6模型
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Optimal deployment of swarm positions in cooperative interception of multiple UAV swarms 被引量:1
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作者 Chengcai Wang Ao Wu +3 位作者 Yueqi Hou Xiaolong Liang Luo Xu Xiaomo Wang 《Digital Communications and Networks》 SCIE CSCD 2023年第2期567-579,共13页
In order to prevent the attacker from breaking through the blockade of the interception,deploying multiple Unmanned Aerial Vehicle(UAV)swarms on the interception line is a new combat style.To solve the optimal deploym... In order to prevent the attacker from breaking through the blockade of the interception,deploying multiple Unmanned Aerial Vehicle(UAV)swarms on the interception line is a new combat style.To solve the optimal deployment of swarm positions in the cooperative interception,an optimal deployment optimization model is presented by minimizing the penetration zones'area and the analytical expression of the optimal deployment positions is deduced.Firstly,from the view of the attackers breaking through the interception line,the situations of vertical penetration and oblique penetration are analyzed respectively,and the mathematical models of penetration zones are obtained under the condition of a single UAV swarm and multiple UAV swarms.Secondly,based on the optimization goal of minimizing the penetration area,the optimal deployment optimization model for swarm positions is proposed,and the analytical solution of the optimal deployment is solved by using the convex programming theory.Finally,the proposed optimal deployment is compared with the uniform deployment and random deployment to verify the validity of the theoretical analysis. 展开更多
关键词 UAV swarm Cooperative interception Deployment optimization Convex programming
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Improved cat swarm optimization for parameter estimation of mixed additive and multiplicative random error model 被引量:2
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作者 Leyang Wang Shuhao Han 《Geodesy and Geodynamics》 EI CSCD 2023年第4期385-391,共7页
To estimate the parameters of the mixed additive and multiplicative(MAM)random error model using the weighted least squares iterative algorithm that requires derivation of the complex weight array,we introduce a deriv... To estimate the parameters of the mixed additive and multiplicative(MAM)random error model using the weighted least squares iterative algorithm that requires derivation of the complex weight array,we introduce a derivative-free cat swarm optimization for parameter estimation.We embed the Powell method,which uses conjugate direction acceleration and does not need to derive the objective function,into the original cat swarm optimization to accelerate its convergence speed and search accuracy.We use the ordinary least squares,weighted least squares,original cat swarm optimization,particle swarm algorithm and improved cat swarm optimization to estimate the parameters of the straight-line fitting MAM model with lower nonlinearity and the DEM MAM model with higher nonlinearity,respectively.The experimental results show that the improved cat swarm optimization has faster convergence speed,higher search accuracy,and better stability than the original cat swarm optimization and the particle swarm algorithm.At the same time,the improved cat swarm optimization can obtain results consistent with the weighted least squares method based on the objective function only while avoiding multiple complex weight array derivations.The method in this paper provides a new idea for theoretical research on parameter estimation of MAM error models. 展开更多
关键词 Mixed additive and multiplicative random error model Parameter estimation Least squares Cat swarm optimization Powell method
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Fault Diagnosis of Power Electronic Circuits Based on Adaptive Simulated Annealing Particle Swarm Optimization 被引量:1
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作者 Deye Jiang Yiguang Wang 《Computers, Materials & Continua》 SCIE EI 2023年第7期295-309,共15页
In the field of energy conversion,the increasing attention on power electronic equipment is fault detection and diagnosis.A power electronic circuit is an essential part of a power electronic system.The state of its i... In the field of energy conversion,the increasing attention on power electronic equipment is fault detection and diagnosis.A power electronic circuit is an essential part of a power electronic system.The state of its internal components affects the performance of the system.The stability and reliability of an energy system can be improved by studying the fault diagnosis of power electronic circuits.Therefore,an algorithm based on adaptive simulated annealing particle swarm optimization(ASAPSO)was used in the present study to optimize a backpropagation(BP)neural network employed for the online fault diagnosis of a power electronic circuit.We built a circuit simulation model in MATLAB to obtain its DC output voltage.Using Fourier analysis,we extracted fault features.These were normalized as training samples and input to an unoptimized BP neural network and BP neural networks optimized by particle swarm optimization(PSO)and the ASAPSO algorithm.The accuracy of fault diagnosis was compared for the three networks.The simulation results demonstrate that a BP neural network optimized with the ASAPSO algorithm has higher fault diagnosis accuracy,better reliability,and adaptability and can more effectively diagnose and locate faults in power electronic circuits. 展开更多
关键词 Fault diagnosis power electronic circuit particle swarm optimization backpropagation neural network
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