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基于人脸识别NMF算法的鲁棒性研究
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作者 吴思远 陈良维 张靓 《成都航空职业技术学院学报》 2025年第2期78-83,共6页
非负矩阵分解(NMF)是一种有效的多变量数据分解方法,而采用不同正则化的NMF算法在特定类型的数据上会具有不同的鲁棒性。通过对比标准NMF算法与基于L_(2,1)范数正则化条件下的NMF算法,在处理不同规模噪声时的数据重建和图像分类能力,以... 非负矩阵分解(NMF)是一种有效的多变量数据分解方法,而采用不同正则化的NMF算法在特定类型的数据上会具有不同的鲁棒性。通过对比标准NMF算法与基于L_(2,1)范数正则化条件下的NMF算法,在处理不同规模噪声时的数据重建和图像分类能力,以此来评估NMF算法在人脸识别中的鲁棒性。其中原始数据集有两种,分别为ORL数据集和YalB数据集;噪声类型有三种:随机噪声、块遮挡噪声和高斯噪声。结果表明,噪声的尺度越小,NMF算法受到的影响越小,集群的性能越好;在相同数据集受到相同噪声污染的情况下,基于L_(2,1)范数的NMF的整体鲁棒性优于标准的NMF算法。 展开更多
关键词 非负矩阵分解 鲁棒性 噪声 人脸识别
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NMF声场分离技术在语音识别中的优化研究
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作者 王树斌 《电声技术》 2025年第1期68-70,共3页
研究基于L2正则化非负矩阵分解(Non-negative Matrix Factorization,NMF)技术的声场分离方法在语音识别中的优化效果。介绍基于声场分离技术的语音识别方法,随后提出通过引入L2正则化项增强NMF的稳定性和稀疏性。为验证所提方法的有效性... 研究基于L2正则化非负矩阵分解(Non-negative Matrix Factorization,NMF)技术的声场分离方法在语音识别中的优化效果。介绍基于声场分离技术的语音识别方法,随后提出通过引入L2正则化项增强NMF的稳定性和稀疏性。为验证所提方法的有效性,实验使用WSJ0-2mix数据集并基于Python实现L2正则化NMF算法,结合HuggingFace Transformers框架对分离后的语音信号进行语音识别测试。结果表明,L2正则化显著降低词错误率,证明了该方法在复杂声场环境下的有效性。 展开更多
关键词 声场分离 L2正则化 非负矩阵分解(nmf) 语音识别
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基于自适应空谱约束的加权残差NMF高光谱图像解混
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作者 陈善学 戚俊杰 《信号处理》 北大核心 2025年第3期553-568,共16页
标准的非负矩阵分解(Nonnegative Matrix Factorization,NMF)模型应用于高光谱图像解混时,由于模型的非凸性、光谱和空间先验信息未充分利用的问题,导致解混精度不高。为提高解混性能,提出了一种基于自适应空谱约束的加权残差非负矩阵... 标准的非负矩阵分解(Nonnegative Matrix Factorization,NMF)模型应用于高光谱图像解混时,由于模型的非凸性、光谱和空间先验信息未充分利用的问题,导致解混精度不高。为提高解混性能,提出了一种基于自适应空谱约束的加权残差非负矩阵分解高光谱图像解混算法。该算法首先,对传统的NMF模型进行改进,利用在迭代过程中原始高光谱图像矩阵与重构图像矩阵之间的残差来构建残差权重因子,为损失函数的每一行分配贡献权重,以减轻噪声的影响,提高算法的鲁棒性。其次,为利用高光谱图像丰富的先验信息,算法引入像元空谱相似度来衡量像元间的相似性以捕获像元在空间及光谱上的联系,并由相似度矩阵自适应地确定像元邻域来构造空间权重因子,提升了丰度的分段平滑性。此外,结合丰度矩阵的固有特征,构造光谱权重因子,促进了丰度的稀疏性。最后,由于高光谱图像具有较高的光谱分辨率,相邻波段的反射值变化较小,因此端元光谱具有一定的平滑度,算法通过端元光谱反射值间的差异分配平滑权重,以调整在迭代过程中端元光谱的平滑程度。本文利用梯度下降推导出算法的乘法更新规则,为证明所提算法的有效性,将其与其他几种算法在模拟数据以及Jasper Ridge和Urban两个真实高光谱数据上进行实验,实验结果验证了该算法具有更好的解混性能。 展开更多
关键词 高光谱图像解混 非负矩阵分解 加权残差 像元空谱相似度 平滑权重
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基于WPG-KNMF的非线性动态过程监控研究
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作者 张成 邓成龙 李元 《控制理论与应用》 北大核心 2025年第3期569-578,共10页
针对非线性动态过程故障检测问题,本文提出一种基于Wasserstein距离投影梯度核非负矩阵分解(WPGKN-MF)的故障检测方法.首先,采用投影梯度方法对KNMF的基矩阵和系数矩阵进行更新.其次,在高维特征空间中,使用Wasserstein距离结合滑动窗口... 针对非线性动态过程故障检测问题,本文提出一种基于Wasserstein距离投影梯度核非负矩阵分解(WPGKN-MF)的故障检测方法.首先,采用投影梯度方法对KNMF的基矩阵和系数矩阵进行更新.其次,在高维特征空间中,使用Wasserstein距离结合滑动窗口方法,构造新的统计量进行故障检测.本文方法将KNMF中迭代方法改进为投影梯度方法,通过KNMF将数据的非线性结构捕获,并结合Wasserstein距离消除样本间自相关性影响.通过一个数值例子和基于工业控制系统执行器诊断方法的开发与应用(DAMADICS)过程的实验数据进行仿真实验,与传统核主成分分析(KPCA)、核非负矩阵分解等方法进行对比,仿真结果验证了本文所提方法的有效性. 展开更多
关键词 核非负矩阵分解 非线性过程 动态过程 投影梯度 Wasserstein距离 故障检测
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Neural Tucker Factorization
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作者 Peng Tang Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期475-477,共3页
Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-... Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-factorization-of-tensors model under the Tucker decomposition framework. 展开更多
关键词 neu tuc f neural tucker factorization latent factorization model high dimensional tensor tucker decomposition framework neural network incomplete tensor latent factorization
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Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana
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作者 Baoshuang Liu Tao Yang +9 位作者 Sicong Kang Fuquan Wang Haixu Zhang Man Xu Wei Wang Jinrui Bai Shaojie Song Qili Dai Yinchang Feng Philip K.Hopke 《Journal of Environmental Sciences》 2025年第5期627-639,共13页
Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data ... Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles.Hourly speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct study.The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,respectively.Alkanes and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite tendency.The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly small.The reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses.Photochemical losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high reactivities.Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its profile.Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles.This study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty. 展开更多
关键词 Volatile organic compounds Dispersion normalization Photochemical loss Factor profile Positive matrix factorization
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萃取精馏回收废剥离液中二乙二醇单甲醚(MDG)和N-甲基甲酰胺(NMF)的研究
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作者 李璟 邓国平 张井峰 《精细石油化工进展》 2025年第4期47-51,共5页
以丙三醇为萃取剂,对废剥离液中沸点接近的二乙二醇单甲醚(MDG)和N-甲基甲酰胺(NMF)进行萃取精馏,逐步分离和回收,并通过流程模拟分析最佳的萃取剂加入量和回流比等设计工况,优化精馏系统的主要工艺参数。结果表明:脱轻塔和脱重塔的最... 以丙三醇为萃取剂,对废剥离液中沸点接近的二乙二醇单甲醚(MDG)和N-甲基甲酰胺(NMF)进行萃取精馏,逐步分离和回收,并通过流程模拟分析最佳的萃取剂加入量和回流比等设计工况,优化精馏系统的主要工艺参数。结果表明:脱轻塔和脱重塔的最佳回流比分别为3.7和0.8;萃取塔的剂液比为10,回流比为12.5;回收塔的最佳回流比为0.6,回收得到的MDG产品质量分数为99.01%,NMF产品质量分数为99.01%,精馏回收系统能耗为16.78 MJ(按每千克产品计算)。采用萃取精馏工艺回收得到高纯度的MDG和NMF产品,拓宽了产品的应用范围,提升了危险废物的资源化利用效果。 展开更多
关键词 废剥离液 二乙二醇单甲醚 N-甲基甲酰胺 萃取精馏
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Predicting CircRNA-Disease Associations via Non-Negative Matrix Factorization Fused with Multiple Similarity Networks
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作者 LU Pengli LI Shiying 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期709-719,共11页
CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs a... CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs and diseases can enhance our understanding of diseases and provide new strategies and tools for early diagnosis,treatment,and disease prevention.However,existing models have limitations in accurately capturing similarities,handling the sparse and noise attributes of association networks,and fully leveraging bioinformatical aspects from multiple viewpoints.To address these issues,this study introduces a new non-negative matrix factorization-based framework called NMFMSN.First,we incorporate circRNA sequence data and disease semantic information to compute circRNA and disease similarity,respectively.Given the sparse known associations between circRNAs and diseases,we reconstruct the network to complete more associations by imputing missing links based on neighboring circRNA and disease interactions.Finally,we integrate these two similarity networks into a non-negative matrix factorization framework to identify potential circRNA-disease associations.Upon conducting 5-fold cross-validation and leave-one-out cross-validation,the AUC values for NMFMSN reach 0.9712 and 0.9768,respectively,outperforming the currently most advanced models.Case studies on lung cancer and hepatocellular carcinoma show that NMFMSN is a good way to predict new associations between circRNAs and diseases. 展开更多
关键词 circRNA-disease associations circRNA sequence data disease semantic information non-negative matrix factorization
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Nonlinear Control for Unstable Networked Plants in the Presence of Actuator and Sensor Limitations Using Robust Right Coprime Factorization
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作者 Yuanhong Xu Mingcong Deng 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期516-527,共12页
In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and l... In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and lower constraints and the sensor in the feedback loop is subjected to network-induced unknown time-varying delay and noise.With this nonlinear control method,we first employ right coprime factorization based on isomorphism and operator theory to factorize the plant,so that bounded input bounded output(BIBO)stability can be guaranteed.Next,continuous-time generalized predictive control(CGPC)is utilized for the unstable operator of the right coprime factorized plant to guarantee inner stability and enables the closed-loop dynamics of the system with predictive characteristics.Meanwhile,a second-Do F(degrees of freedom)switched controller that satisfies a perturbed Bezout identity and a robustness condition is designed.By using the CGPC controller that possesses predictive behavior and the second-Do F switched stabilizer,the overall stability of the plant subjected to actuator limitations is guaranteed.To address sensor limitations that exist in networked plants in the form of delay and noise which often cause system performance degradation,we implement an identity operator definition in the feedback loop to compensate for these adverse effects.Further,a pre-operator is designed to ensure that the plant output tracks the reference input.Finally,the effectiveness of the proposed design scheme is demonstrated by simulations. 展开更多
关键词 Actuator and sensor limitations identity operator definition network-induced limitations robust right coprime factorization unstable plant
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Source apportionment of PM_(2.5) using dispersion normalized positive matrix factorization(DN-PMF)in Beijing and Baoding,China
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作者 Ilhan Ryoo Taeyeon Kim +6 位作者 Jiwon Ryu Yeonseung Cheong Kwang-joo Moon Kwon-ho Jeon Philip K.Hopke Seung-Muk Yi Jieun Park 《Journal of Environmental Sciences》 2025年第9期395-408,共14页
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque... Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities. 展开更多
关键词 Source apportionment Dispersion normalized positive matrix factorization Adjacent cities Inter-city impact Source location Heating season Air quality management
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Latent-Factorization-of-Tensors-Incorporated Battery Cycle Life Prediction
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作者 Minzhi Chen Li Tao +1 位作者 Jungang Lou Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期633-635,共3页
Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and... Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and sustainability of a battery management system(BMS),which relies heavily on the quality of the measured BP data like the voltage(V),current(I),and temperature(T). 展开更多
关键词 health management battery pack bp can latent factorization tensors battery cycle life prediction health management phm battery cycle battery pack battery management system bms which
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基于LinNMF与OMLSA的语音增强算法
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作者 李佳欣 王晓雪 +1 位作者 张斌 杨琼 《无线互联科技》 2025年第16期10-17,23,共9页
针对复杂噪声环境下语音增强任务中传统单一方法难以兼顾结构化与非平稳噪声抑制的问题,文章提出一种融合线性非负矩阵分解(Linear Non-negative Matrix Factorization,LinNMF)与优化改进对数谱幅度估计(Optimally Modified Log-Spectra... 针对复杂噪声环境下语音增强任务中传统单一方法难以兼顾结构化与非平稳噪声抑制的问题,文章提出一种融合线性非负矩阵分解(Linear Non-negative Matrix Factorization,LinNMF)与优化改进对数谱幅度估计(Optimally Modified Log-Spectral Amplitude Estimation,OMLSA)的级联式语音增强框架。该方法通过LinNMF对语音信号进行时频分解,提取语音与结构化噪声的基向量以实现噪声源分离;随后利用OMLSA对残余非平稳噪声进行统计建模,通过时频掩码优化对数谱幅度。对低信噪比(SNR<0 dB)的复杂噪声进行的仿真实验表明,联合方法相较于单独使传统的非负矩阵分解(Nonnegative Matrix Factorization,NMF)或OMLSA,可将信噪比提升至3.5以上,适用于工业检测、车载通信及助听设备等领域。 展开更多
关键词 语音增强 线性非负矩阵分解 优化改进对数谱幅度估计 结构化噪声分离
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融合鲁棒NMF和多尺度CNN的手写气象档案识别算法
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作者 李子祺 勾志竟 雷鸣 《电子设计工程》 2025年第15期1-8,共8页
气象历史档案因年代久远、字迹模糊,现有的手写字符识别算法难以有效应对噪声,导致图像识别率低。针对此问题,应用集成学习思想,提出融合鲁棒非负矩阵分解和多尺度卷积的手写气象档案资料识别算法RNMF-MsCNN,以实现对噪声图像的准确识... 气象历史档案因年代久远、字迹模糊,现有的手写字符识别算法难以有效应对噪声,导致图像识别率低。针对此问题,应用集成学习思想,提出融合鲁棒非负矩阵分解和多尺度卷积的手写气象档案资料识别算法RNMF-MsCNN,以实现对噪声图像的准确识别。该模型分为重构器和分类器两个子模块,重构器模块扩展非负矩阵分解模型,学习低维潜在空间的特征,同时应用鲁棒的L21范数,解决噪声干扰等问题。分类器模块采用多尺度卷积加宽网络结构,更好地捕获节点特征。重构器和分类器相互依存、迭代更新,充分利用原图信息,消除噪声对图像的影响,更好地捕获手写数字的特征信息。通过迭代训练,模型的识别准确率达到了99%以上,优于其他对比算法。实验结果进一步验证了该模型在气象档案数据识别方面的有效性。 展开更多
关键词 深度学习 非负矩阵分解 多尺度卷积 气象档案 字符识别
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基于NMF的交通动态运行风险评估方法
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作者 张勇 谢永亮 +3 位作者 吴克文 王媛媛 吴行 栾森 《公路交通技术》 2025年第5期204-213,共10页
针对传统交通安全分析依赖事故指标存在偶然性、低概率性,且难以在网络层面广泛应用及支撑事前交通安全防控的问题,创新性地提出了一种基于激进驾驶行为ADBs和交通流数据驱动的交通风险替代指标,并采用非负矩阵分解算法NMF对多风险因素... 针对传统交通安全分析依赖事故指标存在偶然性、低概率性,且难以在网络层面广泛应用及支撑事前交通安全防控的问题,创新性地提出了一种基于激进驾驶行为ADBs和交通流数据驱动的交通风险替代指标,并采用非负矩阵分解算法NMF对多风险因素耦合下的风险进行量化研究,以表征交通动态运行风险TDOR。研究结果表明:1)基于事故数据分析,采用ADBs和交通流参数来量化交通安全风险合理可行;2)基于NMF的风险量化评估模型具有可解释性,评估结果合理可行;3)TDOR较高的路段往往集中分布在特定区域内,其峰值大多位于分合流或特殊路段;4)尽管交通事故频发的道路多伴随较高的TDOR值,但两者之间的关系并非完全呈线性关系。本文所提方法有望改变传统的基于事故指标的交通风险评估模式,为事故前的风险预防提供有力依据。 展开更多
关键词 交通安全 交通动态运行风险 非负矩阵分解法 驾驶行为 交通流
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基于NMF-KELM的资源环境承载力评价与预测
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作者 唐勇波 丰娟 龚国勇 《河北省科学院学报》 CAS 2024年第5期50-59,共10页
资源环境承载力评价与预测对区域可持续发展有重要的指导意义。本文提出了基于非负矩阵分解(NMF)和核极限学习机(KELM)的资源环境承载力评价与预测方法,在构建江西省资源环境承载力指标体系的基础上,引入NMF对2005—2020年该地区资源环... 资源环境承载力评价与预测对区域可持续发展有重要的指导意义。本文提出了基于非负矩阵分解(NMF)和核极限学习机(KELM)的资源环境承载力评价与预测方法,在构建江西省资源环境承载力指标体系的基础上,引入NMF对2005—2020年该地区资源环境承载力状况进行量化测度和系统分析,利用加权灰关联法和全排列多边形图示法对承载力结果验证分析,建立了基于NMF-KELM的承载力预测模型并对承载力的演变趋势进行预测。研究结果表明:①2005—2020年,江西省资源环境承载力指数由0.0963提高至0.7975,整体呈波动上升趋势,高速发展的社会经济是承载力的最直接驱动力。②NMF、加权灰关联法和全排列多边形图示法三者反映的趋势和结论是一致的,NMF评价结果更客观。③环境系统成为制约江西省资源环境承载力提高的主要因素,其中万元GDP工业废气排放量是最重要的影响因素。④与BP神经网络和灰色模型相比,基于NMF-KELM的承载力预测模型拟合精度高,能够更好地预测江西省资源环境承载力的演变趋势。 展开更多
关键词 资源环境承载力 非负矩阵分解 加权灰关联法 核极限学习机 江西省
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Evaluating Partitioning Based Clustering Methods for Extended Non-negative Matrix Factorization (NMF)
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作者 Neetika Bhandari Payal Pahwa 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2043-2055,共13页
Data is humongous today because of the extensive use of World WideWeb, Social Media and Intelligent Systems. This data can be very important anduseful if it is harnessed carefully and correctly. Useful information can... Data is humongous today because of the extensive use of World WideWeb, Social Media and Intelligent Systems. This data can be very important anduseful if it is harnessed carefully and correctly. Useful information can beextracted from this massive data using the Data Mining process. The informationextracted can be used to make vital decisions in various industries. Clustering is avery popular Data Mining method which divides the data points into differentgroups such that all similar data points form a part of the same group. Clusteringmethods are of various types. Many parameters and indexes exist for the evaluationand comparison of these methods. In this paper, we have compared partitioningbased methods K-Means, Fuzzy C-Means (FCM), Partitioning AroundMedoids (PAM) and Clustering Large Application (CLARA) on secure perturbeddata. Comparison and identification has been done for the method which performsbetter for analyzing the data perturbed using Extended NMF on the basis of thevalues of various indexes like Dunn Index, Silhouette Index, Xie-Beni Indexand Davies-Bouldin Index. 展开更多
关键词 Clustering CLARA Davies-Bouldin index Dunn index FCM intelligent systems K-means non-negative matrix factorization(nmf) PAM privacy preserving data mining Silhouette index Xie-Beni index
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A Novel CCA-NMF Whitening Method for Practical Machine Learning Based Underwater Direction of Arrival Estimation
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作者 Yun Wu Xinting Li Zhimin Cao 《Journal of Beijing Institute of Technology》 EI CAS 2024年第2期163-174,共12页
Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical problem.Due to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based ... Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical problem.Due to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based DOA estimation methods trained on simulated Gaussian noised array data cannot be directly applied to actual underwater DOA estimation tasks.In order to deal with this problem,environmental data with no target echoes can be employed to analyze the non-Gaussian components.Then,the obtained information about non-Gaussian components can be used to whiten the array data.Based on these considerations,a novel practical sonar array whitening method was proposed.Specifically,based on a weak assumption that the non-Gaussian components in adjacent patches with and without target echoes are almost the same,canonical cor-relation analysis(CCA)and non-negative matrix factorization(NMF)techniques are employed for whitening the array data.With the whitened array data,machine learning based DOA estimation models trained on simulated Gaussian noised datasets can be used to perform underwater DOA estimation tasks.Experimental results illustrated that,using actual underwater datasets for testing with known machine learning based DOA estimation models,accurate and robust DOA estimation performance can be achieved by using the proposed whitening method in different underwater con-ditions. 展开更多
关键词 direction of arrival(DOA) sonar array data underwater disturbance machine learn-ing canonical correlation analysis(CCA) non-negative matrix factorization(nmf)
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基于Deep-Semi-NMF的苹果斑点落叶病检测方法 被引量:1
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作者 傅卓军 胡政 +2 位作者 邓阳君 龙陈锋 朱幸辉 《智慧农业(中英文)》 CSCD 2024年第6期144-154,共11页
[目的/意义]苹果斑点落叶病易导致苹果树叶过早脱落,从而影响苹果品质和产量。因此,如何准确检测此病一直是苹果树病害精准防治的热点问题。由于逆光等因素影响,传统基于图像分割的病斑检测方法难以在复杂背景下准确检测病斑区域边界,... [目的/意义]苹果斑点落叶病易导致苹果树叶过早脱落,从而影响苹果品质和产量。因此,如何准确检测此病一直是苹果树病害精准防治的热点问题。由于逆光等因素影响,传统基于图像分割的病斑检测方法难以在复杂背景下准确检测病斑区域边界,亟需发展苹果斑点落叶病检测新方法,助力苹果树病害精准防治。[方法]针对上述问题,本研究从图像异常检测的角度出发,考虑复杂背景干扰,采用深度半非负矩阵分解理论,结合鲁棒性好的马氏距离度量,提出一种新的深度半非负矩阵分解的马氏距离异常检测方法(Deep Semi-Non-Negative Ma⁃trix Factorization-Based Mahalanobis Distance-Anomaly Detector,DSNMFMAD)。该方法首先利用深度非负矩阵分解(Deep Semi-Non-Negative Matrix Factorization,DSNMF)提取图像中低秩的背景部分和稀疏的异常部分。然后采用基于奇异值分解特征子空间的马氏距离构建病斑检测器,检测器通过计算异常部分每个像元的异常度来标记病斑。最后,分别构建了实验室和自然条件下的两个苹果斑点落叶病数据集,用以验证提出方法的有效性。[结果和讨论]DSNMFMAD在实验室条件和自然条件下对苹果斑点落叶病的识别准确率分别达到了99.8%和87.8%;平均检测速度为0.087和0.091 s/幅。相较于4种经典的异常检测方法和1种深度学习模型,本研究所提出方法的检测准确率在实验室条件下分别提高了0.2%、37.9%、10.3%、0.4%和24.5%;在自然条件下分别提高了2.5%、32.7%、5%、14.8%和3.5%。[结论]本研究提出的DSNMFMAD能够通过DSNMF有效地将图像中的异常部分提取出来,并利用构建的病斑检测器准确地将苹果斑点落叶病位置检测出来。即使在复杂背景条件下,该方法亦获得了比对比方法更高的检测准确度,展现出了优异的病斑检测性能,为苹果斑点落叶病的检测与防治提供了技术参考依据。 展开更多
关键词 图像分割 苹果斑点落叶病 异常检测 深度半非负矩阵分解 马氏距离
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基于改进NMF与相位补偿的胎心音降噪算法 被引量:3
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作者 傅晓雯 李霞 《计算机应用与软件》 北大核心 2024年第4期256-261,共6页
在孕妇体表,通过声音传感器对胎儿心音信号进行采集,结果通常包含多种噪声,常用的滤波方法无法取得满意的降噪效果。为了能够更好地滤除与胎儿心音信号同频的噪声信号,提出改进的非负矩阵分解算法(NMF),对短时幅度谱利用奇异值分解得到... 在孕妇体表,通过声音传感器对胎儿心音信号进行采集,结果通常包含多种噪声,常用的滤波方法无法取得满意的降噪效果。为了能够更好地滤除与胎儿心音信号同频的噪声信号,提出改进的非负矩阵分解算法(NMF),对短时幅度谱利用奇异值分解得到用于NMF的特征数和初始化矩阵,对NMF增加L2,1稀疏限制,使分解得到的胎心音特征呈现更多细节;对短时相位谱采用了增加稀疏限制的相位补偿算法(PSC)。实验结果表明:与常用降噪方法相比,该方法的信噪比至少提升0.52 dB,能更好保留胎儿心音信号特征。 展开更多
关键词 胎儿心音 降噪 非负矩阵分解 相位补偿算法 稀疏限制
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Health risk assessment of trace metal(loid)s in agricultural soils based on Monte Carlo simulation coupled with positive matrix factorization model in Chongqing, southwest China 被引量:4
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作者 MA Jie CHU Lijuan +3 位作者 SUN Jing WANG Shenglan GE Miao DENG Li 《Journal of Mountain Science》 SCIE CSCD 2024年第1期100-112,共13页
This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed ... This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)<total carcinogenic risk ≤ 10^(-4)), with higher risks observed for children compared to adults. The relationship between TMs, their sources, and health risks indicated that urban and industrial sources were primarily associated with As, contributing to 75.1% of carcinogenic risks and 55.7% of non-carcinogenic risks, making them the primary control factors. Meanwhile, agricultural sources were primarily linked to Cd and Pb, contributing to 13.1% of carcinogenic risks and 21.8% of non-carcinogenic risks, designating them as secondary control factors. 展开更多
关键词 Monte Carlo simulation Health risk assessment Trace metal(loid)s Positive matrix factorization Agricultural soils
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