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改进Deep Q Networks的交通信号均衡调度算法
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作者 贺道坤 《机械设计与制造》 北大核心 2025年第4期135-140,共6页
为进一步缓解城市道路高峰时段十字路口的交通拥堵现象,实现路口各道路车流均衡通过,基于改进Deep Q Networks提出了一种的交通信号均衡调度算法。提取十字路口与交通信号调度最相关的特征,分别建立单向十字路口交通信号模型和线性双向... 为进一步缓解城市道路高峰时段十字路口的交通拥堵现象,实现路口各道路车流均衡通过,基于改进Deep Q Networks提出了一种的交通信号均衡调度算法。提取十字路口与交通信号调度最相关的特征,分别建立单向十字路口交通信号模型和线性双向十字路口交通信号模型,并基于此构建交通信号调度优化模型;针对Deep Q Networks算法在交通信号调度问题应用中所存在的收敛性、过估计等不足,对Deep Q Networks进行竞争网络改进、双网络改进以及梯度更新策略改进,提出相适应的均衡调度算法。通过与经典Deep Q Networks仿真比对,验证论文算法对交通信号调度问题的适用性和优越性。基于城市道路数据,分别针对两种场景进行仿真计算,仿真结果表明该算法能够有效缩减十字路口车辆排队长度,均衡各路口车流通行量,缓解高峰出行方向的道路拥堵现象,有利于十字路口交通信号调度效益的提升。 展开更多
关键词 交通信号调度 十字路口 Deep Q networks 深度强化学习 智能交通
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基于1DCNN和LSTM融合的超宽带NLoS/LoS识别方法研究
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作者 郑恩让 孟鑫 +3 位作者 姜苏英 薛晶 张毅 李强 《通信学报》 北大核心 2025年第6期285-302,共18页
为提升超宽带(UWB)定位系统在非视距(NLoS)条件下的测距精度与定位性能,提出一种基于一维卷积-卷积长短期记忆(LSTM)注意力网络(1DCNN-CLANet)的深度学习模型。该模型首先利用卷积神经网络(CNN)提取通道脉冲响应(CIR)的空间特征,并利用... 为提升超宽带(UWB)定位系统在非视距(NLoS)条件下的测距精度与定位性能,提出一种基于一维卷积-卷积长短期记忆(LSTM)注意力网络(1DCNN-CLANet)的深度学习模型。该模型首先利用卷积神经网络(CNN)提取通道脉冲响应(CIR)的空间特征,并利用长短期记忆网络捕捉CIR的时序特征。其次,利用CNN深度挖掘距离数据、信号振幅、最大噪声强度等额外特征。最后,引入注意力机制并构建CIR分支和额外特征分支的融合模型,实现对UWB信号的非视距/视距识别。实验结果表明,复杂环境下1DCNN-CLANet的二分类和四分类识别准确率分别为99.51%和98.47%,优于其他方案。该模型在UWB定位系统中表现出良好的非视距识别能力,具有较强的应用前景。 展开更多
关键词 超宽带 非视距 深度学习模型 卷积神经网络 长短期记忆网络
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基于高光谱成像和MSC1DCNN的大豆种子热损伤无损检测
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作者 谭克竹 孙伟奇 +3 位作者 卓宗慧 李凯诺 张喜海 闫超 《光谱学与光谱分析》 北大核心 2025年第10期2897-2905,共9页
大豆种子由于存储和运输不当,容易产生热损伤问题。热损伤会影响种子的种质质量和发芽率,因此准确地检测热损伤大豆种子对于提高种子品质和农业生产具有重要意义。本文提出了一种基于高光谱成像和多尺度跨通道一维卷积神经网络(MSC1DCNN... 大豆种子由于存储和运输不当,容易产生热损伤问题。热损伤会影响种子的种质质量和发芽率,因此准确地检测热损伤大豆种子对于提高种子品质和农业生产具有重要意义。本文提出了一种基于高光谱成像和多尺度跨通道一维卷积神经网络(MSC1DCNN)的大豆种子热损伤无损检测方法。首先,通过高光谱成像系统获取大豆种子在400~1000 nm波段的光谱数据,并对比分析不同热损伤大豆种子(正常、轻微热损伤、严重热损伤)的光谱曲线特点。发现在420~500 nm蓝光区域和750~1000 nm近红外区域,光谱反射率随着热损伤程度的加深逐渐增大。这些变化为后续的热损伤检测提供了有效的光谱特征依据。其次,采用MSC1DCNN模型进行分类,该模型在测试集上的准确率、召回率和F1分数均达到99.07%,优于支持向量机(SVC)(F1分数为88.32%)、k-近邻算法(KNN)(F1分数为84.39%)及一维卷积神经网络(1D CNN)(F1分数为92.90%)。特别地,MSC1DCNN模型在鉴别轻微热损伤与正常大豆种子时误判率为1.39%,显著低于SVC(12.04%)、KNN(15.74%)和1D CNN(9.72%)模型。最后,还通过发芽试验验证了热损伤对大豆种子发芽率的影响。实验结果表明,热损伤显著降低了大豆种子的发芽率,进一步证实了热损伤对大豆生长的潜在危害。综上所述,本研究提出的MSC1DCNN模型为热损伤大豆种子的无损检测提供了一种有效解决方案,对种质质量检测和自动化筛选工作提供了新的思路。 展开更多
关键词 大豆种子 高光谱 热损伤 一维卷积
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基于1DCNN特征提取和RF分类的滚动轴承故障诊断
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作者 张豪 刘其洪 +1 位作者 李伟光 李漾 《中国测试》 北大核心 2025年第4期137-143,共7页
针对深度学习技术在滚动轴承故障诊断识别中依赖于大量测量数据,相对较少的数据可能会导致过度拟合并降低模型的稳定性等问题,提出一种一维卷积神经网络(1DCNN)和随机森林(RF)相结合的轴承故障诊断模型。将原始时域信号输入搭建的1DCNN... 针对深度学习技术在滚动轴承故障诊断识别中依赖于大量测量数据,相对较少的数据可能会导致过度拟合并降低模型的稳定性等问题,提出一种一维卷积神经网络(1DCNN)和随机森林(RF)相结合的轴承故障诊断模型。将原始时域信号输入搭建的1DCNN网络中,提取原始数据特征向量,对特征向量进行t-SNE降维可视化,验证1DCNN特征提取的有效性。将特征向量输入随机森林实现故障状态识别,解决小样本的滚动轴承故障分类问题。在CWRU数据集和Paderborn数据集上进行实验,针对不同类型、不同损伤程度的轴承,得到分类结果准确率分别达到99.69%和99.16%。与传统的神经网络和机器学习分类模型相比,1DCNN-RF模型具有更高的诊断准确率,可验证所提模型的泛化性和有效性。 展开更多
关键词 滚动轴承 故障诊断 一维卷积神经网络 随机森林
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基于MC2DCNN-LSTM模型的齿轮箱全故障分类识别模型
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作者 陈蓉 王磊 《机电工程》 北大核心 2025年第2期287-297,共11页
针对轧机齿轮箱结构复杂、故障信号识别困难、故障部位分类不清等难题,提出了一种基于多通道二维卷积神经网络(MC2DCNN)与长短期记忆神经网络(LSTM)特征融合的故障诊断方法。首先,设计了一种三通道混合编码的二维样本结构,以达到故障识... 针对轧机齿轮箱结构复杂、故障信号识别困难、故障部位分类不清等难题,提出了一种基于多通道二维卷积神经网络(MC2DCNN)与长短期记忆神经网络(LSTM)特征融合的故障诊断方法。首先,设计了一种三通道混合编码的二维样本结构,以达到故障识别与分类目的,对齿轮箱典型故障进行了自适应分类;其次,该模型将齿轮箱的垂直、水平和轴向三个方向的振动信号融合构造输入样本,结合了二维卷积神经网络与长短时记忆神经网络的优势,设计了与之对应的二维卷积神经网络结构,其相较于传统的单通道信号包含了更多的状态信息;最后,分析了轧制过程数据和已有实验数据,对齿轮故障和齿轮箱全故障进行了特征识别和分类,验证了该模型的准确率。研究结果表明:模型对齿轮箱齿面磨损、齿根裂纹、断齿以及齿面点蚀等典型故障识别的平均准确率达到95.9%,最高准确率为98.6%;相较于单通道信号,多通道信号混合编码方式构造的分类样本极大地提升了神经网络分类的准确性,解调出了更丰富的故障信息。根据轧制过程中的运行数据和实验台数据,验证了该智能诊断方法较传统方法在分类和识别准确率上更具优势,为该方法的工程应用提供了理论基础。 展开更多
关键词 高精度轧机齿轮箱 智能故障诊断 多通道二维卷积神经网络 长短期记忆神经网络 数据分类
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波长注意力1DCNN近红外光谱定量分析算法研究
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作者 陈蓓 蒋思远 郑恩让 《光谱学与光谱分析》 北大核心 2025年第6期1598-1604,共7页
近红外光谱(NIRS)技术因其快速、无损和高效的特点,广泛应用于石油、纺织、食品、制药等领域。然而传统的分析方法在处理变量多、冗余大的光谱数据时,往往存在特征提取困难和建模精度不高等问题。因此提出一种适用于近红外光谱且无需变... 近红外光谱(NIRS)技术因其快速、无损和高效的特点,广泛应用于石油、纺织、食品、制药等领域。然而传统的分析方法在处理变量多、冗余大的光谱数据时,往往存在特征提取困难和建模精度不高等问题。因此提出一种适用于近红外光谱且无需变量筛选的一维波长注意力卷积神经网络(WA-1DCNN)定量建模方法,该建模方法结构简单、通用性强、准确率高。该研究引入波长注意力机制,通过赋予不同波长数据不同的权重,增强模型对重要波长特征的捕捉能力,从而提高定量分析的准确性和鲁棒性。为了验证所提出方法的可行性,采用了公开的4种近红外光谱数据集,将所提出的算法与加入波长筛选偏最小二乘法(PLS)、支持向量回归(SVR)、极限学习机(ELM)三种传统建模方法和一维卷积神经网络(1DCNN)建模方法进行了对比,并通过模型性能指标均方根误差(RMSE)和决定系数(R^(2))对模型性能评估。结果表明没有使用波长筛选算法的WA-1DCNN建模方法性能指标均优于加入波长筛选算法的传统建模方法和1DCNN建模方法。其中在655药片数据集中测试集决定系数为0.9563,相比于1DCNN和加入波长筛选的PLS、SVR、ELM提升了4.34%、12.56%、18.42%、11.59%;在310药片数据集中测试集决定系数为0.9574,相比于1DCNN和加入波长筛选的PLS、SVR、ELM、1DCNN提升了2.72%、8.28%、7.27%、1.17%;在玉米水分和蛋白质数据集中测试集决定系数分别为0.9803和0.9685,相比于1DCNN和加入波长筛选的PLS、SVR、ELM提升了6.24%、1.48%、1.75%、6.08%和5.81%、1.85%、1.58%、2.96%;在小麦蛋白质数据集中测试集决定系数为0.9600,相比于DCNN和加入波长筛选的PLS、SVR、ELM提升了8.67%、5.79%、7.94%、0.56%。为了验证WA-1DCNN模型结构的最佳性,在4种近红外光谱数据集上进行了改变WA-1DCNN模型结构的消融实验。研究结果表明:基于波长注意力卷积神经网络是一种结构简单、通用性强、准确率高的光谱定量分析方法,该方法对于近红外光谱定量分析具有促进作用。 展开更多
关键词 近红外光谱 定量分析 波长注意力机制 一维卷积神经网络
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基于MS1DCNN-BOA-SVM的智能液压系统故障诊断方法
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作者 闫锋 肖成军 +2 位作者 孙一伟 孙有朝 谭忠睿 《机床与液压》 北大核心 2025年第8期174-181,共8页
针对液压系统故障特征提取困难、诊断准确率低等问题,提出一种基于多尺度一维卷积神经网络(MS1DCNN)和贝叶斯搜索优化支持向量机(SVM)的智能故障诊断模型。将多个传感器信号合并为单一输入信号;通过多尺度卷积处理提取关键故障特征,构... 针对液压系统故障特征提取困难、诊断准确率低等问题,提出一种基于多尺度一维卷积神经网络(MS1DCNN)和贝叶斯搜索优化支持向量机(SVM)的智能故障诊断模型。将多个传感器信号合并为单一输入信号;通过多尺度卷积处理提取关键故障特征,构建特征向量;然后,利用贝叶斯搜索优化SVM进行分类识别,构建故障诊断模型;最后,对模型进行训练。结果表明:该模型对柱塞泵和蓄能器的故障诊断准确率分别为99.63%、99.17%;与MS1DCNN、1DCNN、SVM模型相比,该模型在液压系统故障诊断方面具有高准确率、高可靠性和强泛化能力的优势。 展开更多
关键词 液压系统 多尺度卷积神经网络 支持向量机 贝叶斯搜索优化 故障诊断
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基于MSIF-2DCNN的航空发动机中介轴承故障诊断方法
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作者 郭伟超 辛晓行 +3 位作者 杜亮 王景琪 思悦 李淑娟 《振动与冲击》 北大核心 2025年第21期248-257,共10页
由于航空发动机工作环境复杂,故障数据稀缺,且单一传感器难以全面表征中介轴承状态,导致现有诊断方法准确率较低。为此,提出了一种基于多传感器信息融合(multi-sensor information fusion,MSIF)和二维卷积神经网络(2-dimensional convol... 由于航空发动机工作环境复杂,故障数据稀缺,且单一传感器难以全面表征中介轴承状态,导致现有诊断方法准确率较低。为此,提出了一种基于多传感器信息融合(multi-sensor information fusion,MSIF)和二维卷积神经网络(2-dimensional convolutional neural network,2DCNN)的航空发动机中介轴承故障诊断方法。该方法将多个传感器的时域和频域特征融合为一张RGB图像,从而更加全面地表征中介轴承状态。然后,将生成的RGB图像输入2DCNN模型完成故障诊断。在真实航空发动机试验台的轴承故障数据上的测试中,当训练集与测试集比例为1∶9的小样本条件时,部分传感器组合的诊断准确率即可达99%;比例为7∶3时所有传感器组合的准确率均达100%。此外,所提方法的诊断准确率与基础研究相比,至少提高了13%;且超越了进行对比的5种先进方法。结果表明,该方法不仅实现了航空发动机中介轴承故障的快速精准识别,还在小样本条件下展现出了卓越的诊断性能。 展开更多
关键词 航空发动机 中介轴承 多传感器信息融合(MSIF) 故障诊断 卷积神经网络
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基于Attention-1DCNN-CE的加密流量分类方法
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作者 耿海军 董赟 +3 位作者 胡治国 池浩田 杨静 尹霞 《计算机应用》 北大核心 2025年第3期872-882,共11页
针对传统加密流量识别方法存在多分类准确率低、泛化性不强以及易侵犯隐私等问题,提出一种结合注意力机制(Attention)与一维卷积神经网络(1DCNN)的多分类深度学习模型——Attention-1DCNN-CE。该模型包含3个核心部分:1)数据集预处理阶段... 针对传统加密流量识别方法存在多分类准确率低、泛化性不强以及易侵犯隐私等问题,提出一种结合注意力机制(Attention)与一维卷积神经网络(1DCNN)的多分类深度学习模型——Attention-1DCNN-CE。该模型包含3个核心部分:1)数据集预处理阶段,保留原始数据流中数据包间的空间关系,并根据样本分布构建成本敏感矩阵;2)在初步提取加密流量特征的基础上,利用Attention和1DCNN模型深入挖掘并压缩流量的全局与局部特征;3)针对数据不平衡这一挑战,通过结合成本敏感矩阵与交叉熵(CE)损失函数,显著提升少数类别样本的分类精度,进而优化模型的整体性能。实验结果表明,在BOT-IOT和TON-IOT数据集上该模型的整体识别准确率高达97%以上;并且该模型在公共数据集ISCX-VPN和USTC-TFC上表现优异,在不需要预训练的前提下,达到了与ET-BERT(Encrypted Traffic BERT)相近的性能;相较于PERT(Payload Encoding Representation from Transformer),该模型在ISCX-VPN数据集的应用类型检测中的F1分数提升了29.9个百分点。以上验证了该模型的有效性,为加密流量识别和恶意流量检测提供了解决方案。 展开更多
关键词 网络安全 加密流量 注意力机制 一维卷积神经网络 数据不平衡 成本敏感矩阵
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基于MPDCNN的强噪声环境下船舶电力推进器齿轮箱故障诊断方法
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作者 尚前明 蒋婉莹 +2 位作者 周毅 王正强 孙钰波 《中国舰船研究》 北大核心 2025年第2期30-38,共9页
[目的]针对旋转机械在实际工作中因噪声干扰而导致的故障诊断性能下降问题,为提高振动信号的故障特征提取质量和故障诊断能力,提出基于Mel-frequency倒谱系数(MFCC)的并行双通道卷积神经网络(PDCNN)故障诊断方法。[方法]利用MFCC提取含... [目的]针对旋转机械在实际工作中因噪声干扰而导致的故障诊断性能下降问题,为提高振动信号的故障特征提取质量和故障诊断能力,提出基于Mel-frequency倒谱系数(MFCC)的并行双通道卷积神经网络(PDCNN)故障诊断方法。[方法]利用MFCC提取含噪声的振动信号特征,同时设计一种新型并行双通道卷积神经网络结构,并利用该网络进一步挖掘数据的全局特征及更深层次的微小特征,从而提高该方法在强噪声环境下的诊断性能。[结果]不同噪声环境下的实验评估结果表明,该方法在强噪声环境下的故障诊断精度高于98%,其抗噪性能和诊断性能均明显优于其他传统方法。[结论]研究成果可为强噪声环境下的齿轮箱故障诊断提供参考。 展开更多
关键词 船舶电力推进 齿轮箱 故障分析 故障诊断 特征提取 梅尔频率倒谱系数 卷积神经网络
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev... Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller. 展开更多
关键词 pinning control projective synchronization drive system response network
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Exploration of the Biomedical Functions and Applications of Metal-Polyphenol Network Structures
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作者 LI Zhining XU Liangge +1 位作者 ZHANG Yuli WANG Chen 《有色金属(中英文)》 北大核心 2025年第9期1460-1482,共23页
The burgeoning development of nanomedicine has provided state-of-the-art technologies and innovative methodologies for contemporary biomedical research,presenting unprecedented opportunities for resolving pivotal biom... The burgeoning development of nanomedicine has provided state-of-the-art technologies and innovative methodologies for contemporary biomedical research,presenting unprecedented opportunities for resolving pivotal biomedical challenges.Nanomaterials possess distinctive structures and properties.Through the exploration of the fabrication of emerging nanomedicines,multiple functions can be integrated to enable more precise diagnosis and treatment,thereby compensating for the limitations of traditional treatment modalities.Among various substances,polyphenols are natural organic compounds classified as plant secondary metabolites and are ubiquitously present in vegetables,teas,and other plants.Polyphenols are rich in active groups,including hydroxyl,carboxyl,amino,and conjugated double bonds.They exhibit robust adhesion,antioxidant,anti-inflammatory,and antibacterial biological activities and are extensively applied in pharmaceutical formulations.Additionally,polyphenols are characterized by their low cost,ready availability,and do not necessitate intricate chemical synthesis processes.Nevertheless,when natural polyphenol-based nanomedicines are utilized in isolation,they encounter several issues.These include poor water solubility,feeble stability,low bioavailability,the requirement for high dosages,and difficulties in precisely reaching the site of action.To address these concerns,researchers have developed nanomedicines by combining metal ions and functional ligands through metal coordination strategies.Nanomaterials,owing to their unique electronic and optical properties,have been successfully introduced into the realm of medical biology.Nano preparations not only enhance the stability of natural products but also endow them with targeting capabilities,thus enabling precise drug delivery.Polyphenols can further synergize with metal ions,anti-cancer drugs,or photosensitizers via supramolecular interactions to achieve multifunctional synergistic therapies,such as targeted drug delivery,efficacy enhancement,and the construction of engineering scaffolds.Metal-Polyphenol Coordination Polymers(MPCPs),composed of metal ions and phenolic ligands,are regarded as ideal nanoplatforms for disease diagnosis and treatment.In recent years,MPCPs have attracted extensive research in the biomedical field on account of their advantages,including facile synthesis,adjustable structure,excellent biocompatibility,and pH responsiveness.In this review,the classification and preparation strategies of MPCPs were systematically presented.Subsequently,their remarkable achievements in biomedical domains,such as bioimaging,biosensing,drug delivery,tumor therapy,and antimicrobial applications were highlighted.Finally,the principal limitations and prospects of MPCPs were comprehensi vely discussed. 展开更多
关键词 metal polyphenol network NANOTECHNOLOGY NANO-COPPER tumor therapy
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Detection of geohazards caused by human disturbance activities based on convolutional neural networks
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作者 ZHANG Heng ZHANG Diandian +1 位作者 YUAN Da LIU Tao 《水利水电技术(中英文)》 北大核心 2025年第S1期731-738,共8页
Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the envir... Human disturbance activities is one of the main reasons for inducing geohazards.Ecological impact assessment metrics of roads are inconsistent criteria and multiple.From the perspective of visual observation,the environment damage can be shown through detecting the uncovered area of vegetation in the images along road.To realize this,an end-to-end environment damage detection model based on convolutional neural network is proposed.A 50-layer residual network is used to extract feature map.The initial parameters are optimized by transfer learning.An example is shown by this method.The dataset including cliff and landslide damage are collected by us along road in Shennongjia national forest park.Results show 0.4703 average precision(AP)rating for cliff damage and 0.4809 average precision(AP)rating for landslide damage.Compared with YOLOv3,our model shows a better accuracy in cliff and landslide detection although a certain amount of speed is sacrificed. 展开更多
关键词 convolutional neural network DETECTION environment damage CLIFF LANDSLIDE
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Network Pharmacology and Experimental Verification Unraveled The Mechanism of Pachymic Acid in The Treatment of Neuroblastoma
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作者 LIU Hang ZHU Yu-Xin +6 位作者 GUO Si-Lin PAN Xin-Yun XIE Yuan-Jie LIAO Si-Cong DAI Xin-Wen SHEN Ping XIAO Yu-Bo 《生物化学与生物物理进展》 北大核心 2025年第9期2376-2392,共17页
Objective Traditional Chinese medicine(TCM)constitutes a valuable cultural heritage and an important source of antitumor compounds.Poria(Poria cocos(Schw.)Wolf),the dried sclerotium of a polyporaceae fungus,was first ... Objective Traditional Chinese medicine(TCM)constitutes a valuable cultural heritage and an important source of antitumor compounds.Poria(Poria cocos(Schw.)Wolf),the dried sclerotium of a polyporaceae fungus,was first documented in Shennong’s Classic of Materia Medica and has been used therapeutically and dietarily in China for millennia.Traditionally recognized for its diuretic,spleen-tonifying,and sedative properties,modern pharmacological studies confirm that Poria exhibits antioxidant,anti-inflammatory,antibacterial,and antitumor activities.Pachymic acid(PA;a triterpenoid with the chemical structure 3β-acetyloxy-16α-hydroxy-lanosta-8,24(31)-dien-21-oic acid),isolated from Poria,is a principal bioactive constituent.Emerging evidence indicates PA exerts antitumor effects through multiple mechanisms,though these remain incompletely characterized.Neuroblastoma(NB),a highly malignant pediatric extracranial solid tumor accounting for 15%of childhood cancer deaths,urgently requires safer therapeutics due to the limitations of current treatments.Although PA shows multi-mechanistic antitumor potential,its efficacy against NB remains uncharacterized.This study systematically investigated the potential molecular targets and mechanisms underlying the anti-NB effects of PA by integrating network pharmacology-based target prediction with experimental validation of multi-target interactions through molecular docking,dynamic simulations,and in vitro assays,aimed to establish a novel perspective on PA’s antitumor activity and explore its potential clinical implications for NB treatment by integrating computational predictions with biological assays.Methods This study employed network pharmacology to identify potential targets of PA in NB,followed by validation using molecular docking,molecular dynamics(MD)simulations,MM/PBSA free energy analysis,RT-qPCR and Western blot experiments.Network pharmacology analysis included target screening via TCMSP,GeneCards,DisGeNET,SwissTargetPrediction,SuperPred,and PharmMapper.Subsequently,potential targets were predicted by intersecting the results from these databases via Venn analysis.Following target prediction,topological analysis was performed to identify key targets using Cytoscape software.Molecular docking was conducted using AutoDock Vina,with the binding pocket defined based on crystal structures.MD simulations were performed for 100 ns using GROMACS,and RMSD,RMSF,SASA,and hydrogen bonding dynamics were analyzed.MM/PBSA calculations were carried out to estimate the binding free energy of each protein-ligand complex.In vitro validation included RT-qPCR and Western blot,with GAPDH used as an internal control.Results The CCK-8 assay demonstrated a concentration-dependent inhibitory effect of PA on NB cell viability.GO analysis suggested that the anti-NB activity of PA might involve cellular response to chemical stress,vesicle lumen,and protein tyrosine kinase activity.KEGG pathway enrichment analysis suggested that the anti-NB activity of PA might involve the PI3K/AKT,MAPK,and Ras signaling pathways.Molecular docking and MD simulations revealed stable binding interactions between PA and the core target proteins AKT1,EGFR,SRC,and HSP90AA1.RT-qPCR and Western blot analyses further confirmed that PA treatment significantly decreased the mRNA and protein expression of AKT1,EGFR,and SRC while increasing the HSP90AA1 mRNA and protein levels.Conclusion It was suggested that PA may exert its anti-NB effects by inhibiting AKT1,EGFR,and SRC expression,potentially modulating the PI3K/AKT signaling pathway.These findings provide crucial evidence supporting PA’s development as a therapeutic candidate for NB. 展开更多
关键词 pachymic acid network pharmacology molecular dynamics simulation
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Estimation of peer pressure in dynamic homogeneous social networks
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作者 Jie Liu Pengyi Wang +1 位作者 Jiayang Zhao Yu Dong 《中国科学技术大学学报》 北大核心 2025年第5期36-49,35,I0001,I0002,共17页
Social interaction with peer pressure is widely studied in social network analysis.Game theory can be utilized to model dynamic social interaction,and one class of game network models assumes that people’s decision p... Social interaction with peer pressure is widely studied in social network analysis.Game theory can be utilized to model dynamic social interaction,and one class of game network models assumes that people’s decision payoff functions hinge on individual covariates and the choices of their friends.However,peer pressure would be misidentified and induce a non-negligible bias when incomplete covariates are involved in the game model.For this reason,we develop a generalized constant peer effects model based on homogeneity structure in dynamic social networks.The new model can effectively avoid bias through homogeneity pursuit and can be applied to a wider range of scenarios.To estimate peer pressure in the model,we first present two algorithms based on the initialize expand merge method and the polynomial-time twostage method to estimate homogeneity parameters.Then we apply the nested pseudo-likelihood method and obtain consistent estimators of peer pressure.Simulation evaluations show that our proposed methodology can achieve desirable and effective results in terms of the community misclassification rate and parameter estimation error.We also illustrate the advantages of our model in the empirical analysis when compared with a benchmark model. 展开更多
关键词 dynamic network game theory HOMOGENEITY peer pressure social interaction
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Learning the parameters of a class of stochastic Lotka-Volterra systems with neural networks
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作者 WANG Zhanpeng WANG Lijin 《中国科学院大学学报(中英文)》 北大核心 2025年第1期20-25,共6页
In this paper,we propose a neural network approach to learn the parameters of a class of stochastic Lotka-Volterra systems.Approximations of the mean and covariance matrix of the observational variables are obtained f... In this paper,we propose a neural network approach to learn the parameters of a class of stochastic Lotka-Volterra systems.Approximations of the mean and covariance matrix of the observational variables are obtained from the Euler-Maruyama discretization of the underlying stochastic differential equations(SDEs),based on which the loss function is built.The stochastic gradient descent method is applied in the neural network training.Numerical experiments demonstrate the effectiveness of our method. 展开更多
关键词 stochastic Lotka-Volterra systems neural networks Euler-Maruyama scheme parameter estimation
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利用WDCNN-GRU模型的变转速轴承故障诊断技术研究
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作者 刘馨雅 马超 +1 位作者 黄民 张占一 《组合机床与自动化加工技术》 北大核心 2025年第1期138-142,149,共6页
针对变转速工况下,为了提高轴承故障诊断的效率、准确度和稳定性,提出一种基于宽卷积核门控循环的混合神经网络模型。首先,采用计算阶次跟踪对原始信号做角域重采样处理,消除变转速带来的信号不具备周期性、特征混叠、频率偏移等问题;然... 针对变转速工况下,为了提高轴承故障诊断的效率、准确度和稳定性,提出一种基于宽卷积核门控循环的混合神经网络模型。首先,采用计算阶次跟踪对原始信号做角域重采样处理,消除变转速带来的信号不具备周期性、特征混叠、频率偏移等问题;然后,通过宽卷积核卷积网络提取角域信号特征,结合门控循环神经网络捕捉时序信息,使信号特征挖掘更加全面。为验证该方法的有效性,从多个方面结合多个模型进行对比实验。实验结果表明,所提模型的平均准确率均高于对比模型,具备高准确率、高效率及稳定性的特点。 展开更多
关键词 变转速轴承 故障诊断 宽卷积核网络 门控循环网络
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DnCNN-RM:an adaptive SAR image denoising algorithm based on residual networks
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作者 OU Hai-ning LI Chang-di +3 位作者 ZENG Rui-bin WU Yan-feng LIU Jia-ning CHENG Peng 《中国光学(中英文)》 北大核心 2025年第5期1209-1218,共10页
In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantl... In the field of image processing,the analysis of Synthetic Aperture Radar(SAR)images is crucial due to its broad range of applications.However,SAR images are often affected by coherent speckle noise,which significantly degrades image quality.Traditional denoising methods,typically based on filter techniques,often face challenges related to inefficiency and limited adaptability.To address these limitations,this study proposes a novel SAR image denoising algorithm based on an enhanced residual network architecture,with the objective of enhancing the utility of SAR imagery in complex electromagnetic environments.The proposed algorithm integrates residual network modules,which directly process the noisy input images to generate denoised outputs.This approach not only reduces computational complexity but also mitigates the difficulties associated with model training.By combining the Transformer module with the residual block,the algorithm enhances the network's ability to extract global features,offering superior feature extraction capabilities compared to CNN-based residual modules.Additionally,the algorithm employs the adaptive activation function Meta-ACON,which dynamically adjusts the activation patterns of neurons,thereby improving the network's feature extraction efficiency.The effectiveness of the proposed denoising method is empirically validated using real SAR images from the RSOD dataset.The proposed algorithm exhibits remarkable performance in terms of EPI,SSIM,and ENL,while achieving a substantial enhancement in PSNR when compared to traditional and deep learning-based algorithms.The PSNR performance is enhanced by over twofold.Moreover,the evaluation of the MSTAR SAR dataset substantiates the algorithm's robustness and applicability in SAR denoising tasks,with a PSNR of 25.2021 being attained.These findings underscore the efficacy of the proposed algorithm in mitigating speckle noise while preserving critical features in SAR imagery,thereby enhancing its quality and usability in practical scenarios. 展开更多
关键词 SAR images image denoising residual networks adaptive activation function
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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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Studies on the anti-hair loss mechanism of Aquilaria sinensis leaf extract by integrated metabolomics and network pharmacology
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作者 Zhengang Peng Zhengwan Huang +1 位作者 Zhe Liu Xiaoxiao Lin 《日用化学工业(中英文)》 北大核心 2025年第6期767-778,共12页
The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,... The anti-hair loss mechanism of Aquilaria sinensis leaf extract(ASE)has been studied by using metabolomics and network pharmacology.Metabolomics was utilized to comprehensively identify the active constituents of ASE,and the network pharmacology was used to elucidate their anti-hair loss mechanism,which was verified by molecular docking technology.572 active compounds were identified from the ASE by metabolomics methods,where there are 1447 corresponding targets and 492 targets related to hair loss,totaling 88 targets.20 core active substances were identified by constructing a network between common targets and active substances,which include vanillic acid,chorionic acid,caffeic acid and apigenin.The five key targets of TNF,TP53,IL6,PPARG,and EGFR were screened out by the PPI network analysis on 88 common targets.The GO and KEGG pathway enrichment analysis showed that the inflammation,hormone balance,cell growth,proliferation,apoptosis,and oxidative stress are involved.Molecular docking studies have confirmed the high binding affinity between core active compounds and key targets.The drug similarity assessment on these core compounds suggested that they have the potential to be used as potential hair loss treatment drugs.This study elucidates the complex molecular mechanism of ASE in treating hair loss,and provides a reference for the future applications in hair care products. 展开更多
关键词 metabolomics network pharmacology hair loss Aquilaria sinensis leaf extract molecular docking
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