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基于PSO-BP神经网络的分拣机器人视觉反馈跟踪 被引量:1
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作者 杨静宜 白向伟 《国外电子测量技术》 2024年第1期166-172,共7页
针对分拣机器人视觉反馈跟踪精度差、耗时较长的问题,研究基于粒子群算法-反向传播(particle swarm optimization-back propagation,PSO-BP)神经网络的分拣机器人视觉反馈跟踪方法,以提升视觉反馈跟踪效果。依据分拣机器人的视觉反馈信... 针对分拣机器人视觉反馈跟踪精度差、耗时较长的问题,研究基于粒子群算法-反向传播(particle swarm optimization-back propagation,PSO-BP)神经网络的分拣机器人视觉反馈跟踪方法,以提升视觉反馈跟踪效果。依据分拣机器人的视觉反馈信息,建立分拣机器人运动学模型,并求解分拣机器人机械臂输出位置和输入位置的误差函数;利用PSO算法优化BP神经网络的权值与偏置;在权值与偏置优化后的BP神经网络内,输入误差函数,预测分拣机器人视觉反馈跟踪控制量;利用预测视觉反馈跟踪控制量,在线调整增量式比例-积分-微分(proportional-integral-derivative,PID)的参数,输出高精度的分拣机器人视觉反馈跟踪控制量,实现分拣机器人视觉反馈跟踪。实验结果表明,该方法可有效视觉反馈跟踪分拣机器人机械臂的关节角;存在干扰情况下,在运行时间为10 s左右时,阶跃响应趋于稳定;有干扰情况下,视觉反馈跟踪的平均误差为0.09 cm,耗时平均值为0.10 ms;无干扰情况下,平均误差为0.03 cm,耗时平均值为0.04 ms。 展开更多
关键词 pso-bp神经网络 分拣机器人 视觉反馈跟踪 运动学模型 误差函数 增量式PID
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基于泥水平衡盾构掘进参数的PSO-BP神经网络掘进地层识别模型研究 被引量:1
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作者 陈志鼎 李小龙 +2 位作者 李广聪 万山涛 董亿 《水电能源科学》 北大核心 2024年第2期67-71,共5页
为解决泥水平衡盾构机在掘进时无法准确地实时识别掘进地层的问题,以珠三角水资源配置工程为例,研究泥水平衡盾构机的盾构推力、掘进速度、刀盘转速、刀盘扭矩在不同地层下的变化规律,提出基于掘进参数的PSO-BP神经网络掘进地层识别方法... 为解决泥水平衡盾构机在掘进时无法准确地实时识别掘进地层的问题,以珠三角水资源配置工程为例,研究泥水平衡盾构机的盾构推力、掘进速度、刀盘转速、刀盘扭矩在不同地层下的变化规律,提出基于掘进参数的PSO-BP神经网络掘进地层识别方法,建立盾构推力、掘进速度、刀盘转速、刀盘扭矩4种掘进参数为输入集,地层编码为输出集的地层识别模型。工程数据的验证结果表明,该模型在珠三角水资源配置工程数据集上的掘进地层的识别准确率达99.07%,PSO-BP神经网络算法的识别准确率明显高于BP、RF、RBF、CNN等机械学习算法。 展开更多
关键词 泥水平衡盾构机 掘进参数 地层识别 pso-bp神经网络
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基于改进 PSO-BPNN 的拖拉机液压油品质监测
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作者 李仲兴 朱方喜 +1 位作者 刘炳晨 郗少华 《中国农机化学报》 北大核心 2024年第10期140-146,共7页
为实现对拖拉机液压油品质的有效监测,保障拖拉机液压系统的平稳运行,基于改进PSO-BPNN设计一种针对拖拉机液压油品质的监测方法。首先,为研究拖拉机液压油品质恶化情况,在液压油新油的基础上配制不同比例的液压油油样。随后,搭建拖拉... 为实现对拖拉机液压油品质的有效监测,保障拖拉机液压系统的平稳运行,基于改进PSO-BPNN设计一种针对拖拉机液压油品质的监测方法。首先,为研究拖拉机液压油品质恶化情况,在液压油新油的基础上配制不同比例的液压油油样。随后,搭建拖拉机液压油品质监测试验装置,并依据试验装置采集与监测液压油粘度、介电常数和温度参数。然后,设计并搭建一种基于改进PSO-BPNN的拖拉机液压油品质监测模型,该模型利用正弦调整惯性权重的PSO算法优化BPNN的权值和阈值初始值,提高模型收敛效率。最后,为验证基于改进PSO-BPNN的液压油品质监测方法的可行性,与基于传统BPNN、标准PSO-BPNN的拖拉机液压油品质监测模型进行对比。结果表明,基于改进PSO-BPNN的拖拉机液压油品质监测方法具有较快的收敛速度,监测正确率达到97.78%,为优化拖拉机液压油品质监测方法提供参考。 展开更多
关键词 拖拉机 液压油品质 改进PSO算法 BP神经网络
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基于PSO-BP的岩性识别方法研究
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作者 高雅田 杨俊国 《计算机与数字工程》 2024年第4期1119-1124,共6页
近些年来,数据分析、深度学习技术取得了长足的发展,并为社会带来了可观的收益。故利用深度学习手段进行岩性识别也成为了一个研究热点。岩性识别是录井解释的核心业务,准确而有效地预测储层性质对石油勘探工作有着重大意义。为解决传... 近些年来,数据分析、深度学习技术取得了长足的发展,并为社会带来了可观的收益。故利用深度学习手段进行岩性识别也成为了一个研究热点。岩性识别是录井解释的核心业务,准确而有效地预测储层性质对石油勘探工作有着重大意义。为解决传统岩性识别方法成本高、耗时长等缺点。论文利用松辽盆地中若干井的测井数据进行模型研究,提出了一种基于PSO-BP的岩性识别方法。通过对测井源数据进行数据预处理、构建网络识别模型、优化岩性识别模型、评价模型输出结果等步骤,实现基于PSO-BP岩性识别方法。经过反复试验,结果表明采用PSO-BP的岩性识别方法对岩性进行识别的平均准确率可达92.2%,为储层预测工作提供了可靠的支撑。 展开更多
关键词 BP神经网络 粒子群优化算法 岩性识别 数据预处理 KNN 支持向量机
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基于SBAS-InSAR和PSO-BP模型的鲁南高铁沿线地表沉降监测与预测 被引量:1
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作者 何虎振 刘国林 +1 位作者 王凤云 陶秋香 《大地测量与地球动力学》 CSCD 北大核心 2024年第8期820-826,共7页
选取38景Sentinel-1A SAR影像,利用SBAS-InSAR技术获取2019-02~2022-11鲁南高铁曲阜-菏泽段沿线5 km区域的地表沉降结果,分析其分布特征和规律,并利用PSO-BP模型对若干特征点进行沉降预测。结果表明,高铁沿线0.1 km范围内地表年均形变... 选取38景Sentinel-1A SAR影像,利用SBAS-InSAR技术获取2019-02~2022-11鲁南高铁曲阜-菏泽段沿线5 km区域的地表沉降结果,分析其分布特征和规律,并利用PSO-BP模型对若干特征点进行沉降预测。结果表明,高铁沿线0.1 km范围内地表年均形变速率为-20~15 mm/a,最大沉降速率为25.46 mm/a,最大抬升速率为17.43 mm/a;PSO-BP模型得到的沉降预测值的RMSE为5.8~12.4 mm,可对地表沉降进行较好的预测。 展开更多
关键词 鲁南高铁 SBAS-InSAR pso-bp模型 地表沉降 沉降预测
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基于GA-BP和PSO-BP神经网络的SLM GH3625高温合金残余应力预测研究
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作者 曾权 李鑫 +5 位作者 王克鲁 鲁世强 刘杰 黄文杰 周潼 汪增强 《塑性工程学报》 CAS CSCD 北大核心 2024年第3期193-199,共7页
采用PSO-BP和GA-BP混合算法的人工神经网络模型预测了选区激光熔化成形GH3625高温合金的残余应力。通过响应面法为实验设计生成样本集,以激光功率、扫描速度和扫描间距作为模型的输入层,以残余应力作为模型的输出层进行预测优化。采用... 采用PSO-BP和GA-BP混合算法的人工神经网络模型预测了选区激光熔化成形GH3625高温合金的残余应力。通过响应面法为实验设计生成样本集,以激光功率、扫描速度和扫描间距作为模型的输入层,以残余应力作为模型的输出层进行预测优化。采用相关系数R^(2)和平均绝对相对误差e_(AARE)评价指标对预测模型进行了验证和对比分析。结果表明:BP、 GA-BP和PSO-BP神经网络模型均能够较好地预测不同工艺参数下GH3625高温合金的残余应力,且通过算法优化后的BP神经网络具有更高的预测精度。其中GA-BP神经网络对选区激光熔化成形GH3625高温合金残余应力的预测精度最高,模型性能更优越,其相关系数R^(2)和相对平均绝对误差e_(AARE)分别为0.909和2.06%。 展开更多
关键词 选区激光熔化 GH3625高温合金 残余应力 GA-BP神经网络 pso-bp神经网络
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Multi-Source Underwater DOA Estimation Using PSO-BP Neural Network Based on High-Order Cumulant Optimization
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作者 Haihua Chen Jingyao Zhang +3 位作者 Bin Jiang Xuerong Cui Rongrong Zhou Yucheng Zhang 《China Communications》 SCIE CSCD 2023年第12期212-229,共18页
Due to the complex and changeable environment under water,the performance of traditional DOA estimation algorithms based on mathematical model,such as MUSIC,ESPRIT,etc.,degrades greatly or even some mistakes can be ma... Due to the complex and changeable environment under water,the performance of traditional DOA estimation algorithms based on mathematical model,such as MUSIC,ESPRIT,etc.,degrades greatly or even some mistakes can be made because of the mismatch between algorithm model and actual environment model.In addition,the neural network has the ability of generalization and mapping,it can consider the noise,transmission channel inconsistency and other factors of the objective environment.Therefore,this paper utilizes Back Propagation(BP)neural network as the basic framework of underwater DOA estimation.Furthermore,in order to improve the performance of DOA estimation of BP neural network,the following three improvements are proposed.(1)Aiming at the problem that the weight and threshold of traditional BP neural network converge slowly and easily fall into the local optimal value in the iterative process,PSO-BP-NN based on optimized particle swarm optimization(PSO)algorithm is proposed.(2)The Higher-order cumulant of the received signal is utilized to establish the training model.(3)A BP neural network training method for arbitrary number of sources is proposed.Finally,the effectiveness of the proposed algorithm is proved by comparing with the state-of-the-art algorithms and MUSIC algorithm. 展开更多
关键词 gaussian colored noise higher-order cumulant multiple sources particle swarm optimization(PSO)algorithm pso-bp neural network
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基于PSO-BP神经网络的新能源汽车销量预测模型
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作者 王训洪 郝同铮 马聪 《科学技术与工程》 北大核心 2024年第31期13467-13474,共8页
为有效避免新能源汽车销量产销不平衡问题,通过粒子群优化算法(particle swarm optimization,PSO)优化反向传播(back propagation,BP)网络的参数迭代过程,弥补优化原本BP神经网络易陷入局部最优和收敛速度较慢的缺陷,构建了基于PSO-BP... 为有效避免新能源汽车销量产销不平衡问题,通过粒子群优化算法(particle swarm optimization,PSO)优化反向传播(back propagation,BP)网络的参数迭代过程,弥补优化原本BP神经网络易陷入局部最优和收敛速度较慢的缺陷,构建了基于PSO-BP神经网络的新能源汽车销量预测模型,以比亚迪为例进行指数平滑法预测、BP和PSO-BP神经网络预测。结果表明BP神经网络模型相比于指数平滑模型在均方误差(mean square error,MSE)、平均绝对值误差(mean absolute error,MAE)和平均绝对百分比误差(mean absolute percentage error,MAPE)指标上预测性能优势显著,经过粒子群算法优化后的BP神经网络模型的MSE下降近7×107,MAE下降3346,MAPE下降1.71%。可见基于PSO-BP神经网络的新能源汽车销量预测模型优于指数平滑模型和BP神经网络模型,粒子群优化的BP神经网络能够使模型跳出局部最优,加快收敛速度,预测结果的误差率更低,精度更高,且对企业的计划和生产具有指导作用。 展开更多
关键词 新能源汽车 PSO算法 pso-bp神经网络 销量预测模型
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基于PSO-BP模糊PID的变距取苗机构控制系统设计
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作者 李润泽 王卫兵 李小军 《农机化研究》 北大核心 2025年第2期9-18,共10页
为满足番茄、辣椒等蔬菜作物的移栽需求,基于向下取苗原理设计了一种适用72穴和128穴两种主要番茄钵苗穴盘规格的变距取苗机构,通过建立数学模型获得了取苗机械手参数的目标函数,并利用粒子群和模拟退火混合算法对其结构参数进行优化。... 为满足番茄、辣椒等蔬菜作物的移栽需求,基于向下取苗原理设计了一种适用72穴和128穴两种主要番茄钵苗穴盘规格的变距取苗机构,通过建立数学模型获得了取苗机械手参数的目标函数,并利用粒子群和模拟退火混合算法对其结构参数进行优化。同时,为实现变距取苗机构的精确控制,提出了一种基于PSO-BP的模糊PID算法以提高控制精度,介绍了系统的结构与工作原理,并通过选型计算与分析建模建立了控制系统的数学模型。针对传统PID控制器稳定性差、响应速度慢等不足之处,利用PSO-BP模糊PID对控制器的参数进行在线调整,以满足控制过程中对参数的不同需求。仿真结果与试验数据的分析表明:在参数相同条件下,基于PSO-BP模糊PID控制系统系统稳定性更好、响应速度更快,具有良好的鲁棒性,提升取苗成功率的同时降低了基质损伤率,能够满足变距取苗机构高精度快速稳定控制的需求。 展开更多
关键词 变距取苗机构 pso-bp神经网络 模糊PID算法 控制系统
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GA-BP和PSO-BP预测模型在九龙矿煤层底板突水预测中的应用研究
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作者 刘滢 卢兰萍 +3 位作者 王铁记 靳子栋 张会松 卫皓皓 《煤炭技术》 CAS 2024年第6期169-173,共5页
目前,煤层开采环境复杂,随着开采深度、开采强度的增加,面临多变的突水因素和复杂的突水机理,且各因素间相互联系的不确定性,使底板突水预测的难度不断增加。对GA-BP与PSO-BP两种组合优化方法进行描述、对比。两种组合优化方法克服了神... 目前,煤层开采环境复杂,随着开采深度、开采强度的增加,面临多变的突水因素和复杂的突水机理,且各因素间相互联系的不确定性,使底板突水预测的难度不断增加。对GA-BP与PSO-BP两种组合优化方法进行描述、对比。两种组合优化方法克服了神经网络容易收敛到局部最小值,以及收敛速度慢的缺点,对煤层底板突水都能实现较高精度,具有强大的泛化能力。通过对两种组合优化方法的预测模型做对比,发现GA-BP模型更优于PSO-BP模型,证明GA-BP组合优化方法更适合对底板突水危险性进行预测。 展开更多
关键词 GA-BP pso-bp BP神经网络 组合优化方法 底板突水
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基于PSO-BP神经网络的轮胎负荷测量方法
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作者 曹旭 张舜 +1 位作者 许彦峰 王青春 《轮胎工业》 CAS 2024年第5期312-315,共4页
研究基于粒子群优化(PSO)算法-BP神经网络的轮胎负荷测量方法。将采集的轮胎状态信息与提取到的加速度特征输入到BP神经网络,对轮胎负荷进行回归预测,使用PSO算法优化BP神经网络的权值与阈值,得到轮胎状态信息与轮胎负荷的关系。结果表... 研究基于粒子群优化(PSO)算法-BP神经网络的轮胎负荷测量方法。将采集的轮胎状态信息与提取到的加速度特征输入到BP神经网络,对轮胎负荷进行回归预测,使用PSO算法优化BP神经网络的权值与阈值,得到轮胎状态信息与轮胎负荷的关系。结果表明,采用PSO-BP神经网络预测轮胎负荷误差为1.8656%,PSO-BP神经网络预测精度较高,在转变工况条件下,预测误差为2.496%。 展开更多
关键词 轮胎负荷 轮胎状态信息 加速度特征 粒子群优化算法 BP神经网络
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基于PSO-BP的贵州省物流需求预测研究 被引量:1
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作者 于颖 王婷 《电子商务评论》 2024年第1期266-275,共10页
合理预测物流需求对物流业高质量发展具有重要意义。为提高预测结果的准确性,以贵州省为例,构建PSO-BP模型对未来三年的物流需求进行预测。首先选取12个指标建立指标体系,并进行灰色关联度验证。然后运用粒子群算法(PSO)优化反向传播网... 合理预测物流需求对物流业高质量发展具有重要意义。为提高预测结果的准确性,以贵州省为例,构建PSO-BP模型对未来三年的物流需求进行预测。首先选取12个指标建立指标体系,并进行灰色关联度验证。然后运用粒子群算法(PSO)优化反向传播网络(BP),实证结果显示,PSO-BP的预测效果和拟合能力均优于单一的BP模型。最后使用GM(1,1)获得12个指标未来三年的预测值,将其代入PSO-BP模型得到贵州省未来三年的物流需求量。 展开更多
关键词 物流需求 pso-bp模型 需求预测
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Pluggable multitask diffractive neural networks based on cascaded metasurfaces 被引量:4
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作者 Cong He Dan Zhao +8 位作者 Fei Fan Hongqiang Zhou Xin Li Yao Li Junjie Li Fei Dong Yin-Xiao Miao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been c... Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been considered as one of the powerful tools in promoting the fields of imaging processing and object recognition.However,the existing optical system architecture cannot be reconstructed to the realization of multi-functional artificial intelligence systems simultaneously.To push the development of this issue,we propose the pluggable diffractive neural networks(P-DNN),a general paradigm resorting to the cascaded metasurfaces,which can be applied to recognize various tasks by switching internal plug-ins.As the proof-of-principle,the recognition functions of six types of handwritten digits and six types of fashions are numerical simulated and experimental demonstrated at near-infrared regimes.Encouragingly,the proposed paradigm not only improves the flexibility of the optical neural networks but paves the new route for achieving high-speed,low-power and versatile artificial intelligence systems. 展开更多
关键词 optical neural networks diffractive deep neural networks cascaded metasurfaces
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Screening biomarkers for spinal cord injury using weighted gene co-expression network analysis and machine learning 被引量:5
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作者 Xiaolu Li Ye Yang +3 位作者 Senming Xu Yuchang Gui Jianmin Chen Jianwen Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2723-2734,共12页
Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is s... Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is still limited understanding of the peripheral immune inflammato ry response in spinal cord inju ry.In this study.we obtained microRNA expression profiles from the peripheral blood of patients with spinal co rd injury using high-throughput sequencing.We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus(GEO)database(GSE151371).We identified 54 differentially expressed microRNAs and 1656 diffe rentially expressed genes using bioinformatics approaches.Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways,such as neutrophil extracellular trap formation pathway,T cell receptor signaling pathway,and nuclear factor-κB signal pathway,we re abnormally activated or inhibited in spinal cord inju ry patient samples.We applied an integrated strategy that combines weighted gene co-expression network analysis,LASSO logistic regression,and SVM-RFE algorithm and identified three biomarke rs associated with spinal cord injury:ANO10,BST1,and ZFP36L2.We verified the expression levels and diagnostic perfo rmance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve.Quantitative polymerase chain reaction results showed that ANO20 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients.We also constructed a small RNA-mRNA interaction network using Cytoscape.Additionally,we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal co rd injury patients using the CIBERSORT tool.The proportions of naive B cells,plasma cells,monocytes,and neutrophils were increased while the proportions of memory B cells,CD8^(+)T cells,resting natural killer cells,resting dendritic cells,and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects,and ANO10,BST1 and ZFP26L2we re closely related to the proportion of certain immune cell types.The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal co rd inju ry and suggest that ANO10,BST2,and ZFP36L2 are potential biomarkers for spinal cord injury.The study was registe red in the Chinese Clinical Trial Registry(registration No.ChiCTR2200066985,December 12,2022). 展开更多
关键词 bioinformatics analysis BIOMARKER CIBERSORT GEO dataset LASSO miRNA-mRNA network RNA sequencing spinal cord injury SVM-RFE weighted gene co-expression network analysis
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基于PSO-BP-UKF算法的锂电池SOC估计方法研究
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作者 李洋 石振刚 《电器与能效管理技术》 2024年第6期42-48,共7页
锂电池的荷电状态(SOC)是锂电池质量管理的核心之一。基于有效的SOC估计是确保锂电池安全高效工作的必要条件,提出一种利用粒子群算法(PSO)优化反向传播(BP)神经网络,并将优化后的BP神经网络SOC输出值作为无迹卡尔曼滤波(UKF)观测值的... 锂电池的荷电状态(SOC)是锂电池质量管理的核心之一。基于有效的SOC估计是确保锂电池安全高效工作的必要条件,提出一种利用粒子群算法(PSO)优化反向传播(BP)神经网络,并将优化后的BP神经网络SOC输出值作为无迹卡尔曼滤波(UKF)观测值的锂电池SOC估计方法。使用来自马里兰大学的FUDS工况电池测试数据,将所提的PSO-BP-UKF算法与GA-BP-UKF算法、BP算法进行对比。结果表明,在25℃环境下,PSO-BP-UKF算法的最大偏差<3.17%,平均误差<6.44%,均方根偏差<0.0025,相比GA-BP-UKF算法和BP方法都有较大幅度的提高,说明所提算法具备有效性与实用性。 展开更多
关键词 SOC估计 无迹卡尔曼滤波算法 锂电池 粒子群算法 BP神经网络
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Social-ecological perspective on the suicidal behaviour factors of early adolescents in China:a network analysis 被引量:3
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作者 Yuan Li Peiying Li +5 位作者 Mengyuan Yuan Yonghan Li Xueying Zhang Juan Chen Gengfu Wang Puyu Su 《General Psychiatry》 CSCD 2024年第1期143-150,共8页
Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To expl... Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To explore the risk and protective factors of suicidal behaviours(ie,suicidal ideation,plans and attempts)in early adolescence in China using a social-ecological perspective.Methods Using data from the cross-sectional project‘Healthy and Risky Behaviours Among Middle School Students in Anhui Province,China',stratified random cluster sampling was used to select 5724 middle school students who had completed self-report questionnaires in November 2020.Network analysis was employed to examine the correlates of suicidal ideation,plans and attempts at four levels,namely individual(sex,academic performance,serious physical llness/disability,history of self-harm,depression,impulsivity,sleep problems,resilience),family(family economic status,relationship with mother,relationship with father,family violence,childhood abuse,parental mental illness),school(relationship with teachers,relationship with classmates,school-bullying victimisation and perpetration)and social(social support,satisfaction with society).Results In total,37.9%,19.0%and 5.5%of the students reported suicidal ideation,plans and attempts in the past 6 months,respectively.The estimated network revealed that suicidal ideation,plans and attempts were collectively associated with a history of self-harm,sleep problems,childhood abuse,school bullying and victimisation.Centrality analysis indicated that the most influential nodes in the network were history of self-harm and childhood abuse.Notably,the network also showed unique correlates of suicidal ideation(sex,weight=0.60;impulsivity,weight=0.24;family violence,weight=0.17;relationship with teachers,weight=-0.03;school-bullying perpetration,weight=0.22),suicidal plans(social support,weight=-0.15)and suicidal attempts(relationship with mother,weight=-0.10;parental mental llness,weight=0.61).Conclusions This study identified the correlates of suicidal ideation,plans and attempts,and provided practical implications for suicide prevention for young adolescents in China.Firstly,this study highlighted the importance of joint interventions across multiple departments.Secondly,the common risk factors of suicidal ideation,plans and attempts were elucidated.Thirdly,this study proposed target interventions to address the unique influencing factors of suicidal ideation,plans and attempts. 展开更多
关键词 network ANALYSIS PREVENTION
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基于PSO-BP神经网络的磨机传动系统模型修正
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作者 陶征 鲍现乐 +1 位作者 郭勤涛 周天洋 《机械传动》 北大核心 2024年第2期48-53,共6页
针对磨机传动系统结构的复杂性、部件间约束条件的不确定性以及非线性等因素,提出了一种基于PSO-BP神经网络的有限元模型修正方法。通过改进BP神经网络逼近设计参数和特征量间的非线性映射关系,结合实际结构响应,利用神经网络的泛化特性... 针对磨机传动系统结构的复杂性、部件间约束条件的不确定性以及非线性等因素,提出了一种基于PSO-BP神经网络的有限元模型修正方法。通过改进BP神经网络逼近设计参数和特征量间的非线性映射关系,结合实际结构响应,利用神经网络的泛化特性,得到了模型设计参数值。修正后频率误差从最高18%降到4%左右,修正系数误差范围均在0.5%以内,明显提高了有限元模型精度;同时,又不需要大量迭代求解步骤,避开了传统反问题模型修正法的复杂非线性优化过程,提升了效率,验证了PSO-BP神经网络法应用于大型磨机传动系统上的可行性,为后续传动系统整体分析奠定了基础。 展开更多
关键词 模型修正 神经网络 模态分析 相似设计 分层修正
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基于SBAS-InSAR与MA-PSO-BP的南京河西地区地表沉降监测及预测分析 被引量:1
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作者 毕凌宇 孙承志 乔申 《测绘通报》 CSCD 北大核心 2024年第4期48-53,82,共7页
针对南京河西地区城市化进展的不断加快及对该地区的沉降预测研究较少的问题,本文提出一种基于小基线集合成孔径雷达干涉测量(SBAS-InSAR)与滑动平均-粒子群优化-反向传播神经网络算法(MA-PSO-BP)的城市地表形变监测及预测模型。利用202... 针对南京河西地区城市化进展的不断加快及对该地区的沉降预测研究较少的问题,本文提出一种基于小基线集合成孔径雷达干涉测量(SBAS-InSAR)与滑动平均-粒子群优化-反向传播神经网络算法(MA-PSO-BP)的城市地表形变监测及预测模型。利用2020年3月—2022年3月的22景Sentinel-1A升降轨数据对南京河西地区进行沉降监测,获取研究区升降轨形变量,分析河西地区的沉降趋势与成因,并对监测得到的沉降值进行滑动平均插值,将其作为PSO-BP网络模型的样本输入,构建网络预测模型。结果表明,SBAS-InSAR技术能够有效监测城市长时间的沉降,南京河西地区存在不同程度的沉降,沉降速率为-25.3~20.5 mm/a。对比历史沉降研究,沉降趋势由北部向南部扩张,结合SBAS-InSAR沉降监测数据,分别与BP神经网络和PSO-BP神经网络预测模型进行对比,样本数据经过插值后沉降预测模型的精度最高。 展开更多
关键词 地表形变监测 预测模型 滑动平均插值 SBAS-InSAR pso-bp
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Image super‐resolution via dynamic network 被引量:1
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作者 Chunwei Tian Xuanyu Zhang +2 位作者 Qi Zhang Mingming Yang Zhaojie Ju 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期837-849,共13页
Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely exp... Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction block.The residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐resolution.To enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying scenes.To prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained features.Also,a residual learning operation is embedded in the refinement block to prevent long‐term dependency problem.Finally,a construction block is responsible for reconstructing high‐quality images.Designed heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital devices.Experimental results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and complexity.The code of DSRNet can be obtained at https://github.com/hellloxiaotian/DSRNet. 展开更多
关键词 CNN dynamic network image super‐resolution lightweight network
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Mapping Network-Coordinated Stacked Gated Recurrent Units for Turbulence Prediction 被引量:1
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作者 Zhiming Zhang Shangce Gao +2 位作者 MengChu Zhou Mengtao Yan Shuyang Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1331-1341,共11页
Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes i... Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes in the flow field.In this study,we propose a novel deep learning method,named mapping net-work-coordinated stacked gated recurrent units(MSU),for pre-dicting pressure on a circular cylinder from velocity data.Specifi-cally,our coordinated learning strategy is designed to extract the most critical velocity point for prediction,a process that has not been explored before.In our experiments,MSU extracts one point from a velocity field containing 121 points and utilizes this point to accurately predict 100 pressure points on the cylinder.This method significantly reduces the workload of data measure-ment in practical engineering applications.Our experimental results demonstrate that MSU predictions are highly similar to the real turbulent data in both spatio-temporal and individual aspects.Furthermore,the comparison results show that MSU predicts more precise results,even outperforming models that use all velocity field points.Compared with state-of-the-art methods,MSU has an average improvement of more than 45%in various indicators such as root mean square error(RMSE).Through comprehensive and authoritative physical verification,we estab-lished that MSU’s prediction results closely align with pressure field data obtained in real turbulence fields.This confirmation underscores the considerable potential of MSU for practical applications in real engineering scenarios.The code is available at https://github.com/zhangzm0128/MSU. 展开更多
关键词 Convolutional neural network deep learning recurrent neural network turbulence prediction wind load predic-tion.
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