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Characterization of dissolved organic matter in urban sewage using excitation emission matrix fluorescence spectroscopy and parallel factor analysis 认领 引用 被引量：48
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作者 Weidong Guo Jing Xu +3 位作者 Jiangping Wang Yingrou Wen Jianfu Zhuo Yuchao Yan 《Journal of Environmental Sciences》 SCIE EI CAS 2010年第11期1728-1734,共7页
Wastewater dissolved organic matter （DOM） from different processing stages of a sewage treatment plant in Xiamen was characterized using fluorescence and absorption spectroscopy. Parallel factor analysis modeling of... Wastewater dissolved organic matter （DOM） from different processing stages of a sewage treatment plant in Xiamen was characterized using fluorescence and absorption spectroscopy. Parallel factor analysis modeling of excitation-emission matrix spectra revealed five fluorescent components occurring in sewage DOM： one protein-like （C1）, three humic-like （C2, C4 and C5） and one xenobiotic-like （C3） components. During the aerated grit chamber and primary sedimentation tank stage, there was only a slight decrease in fluorescence intensity and the absorption coefficient at 350 nm （a 350 ）. During the second aeration stage, high concentration of protein-like and short-wavelength-excited humic-like components were significantly degraded accompanied by significant loss of DOC （80%） and a 350 （30%）, indicating that C1 and C2 were the dominant constituents of sewage DOM. As a result, long-wavelength- excited C4 and C5 became the dominant humic-like components and the DOM molecular size inferred from the variation of spectral slope S （300–650 nm） and specific absorption （a 280 /DOC） increased. Combination use of F max of C1 and the ratio of C1/C5, or a 350 may provide a quantitative indication for the relative amount of raw or treated sewage in aquatic environment. 展开更多
关键词 dissolved organic matter sewage fluorescence EEM parallel factor analysis
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Assessment of phytoplankton class abundance using fluorescence excitation-emission matrix by parallel factor analysis and nonnegative least squares 认领 引用
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作者 苏荣国 陈小娜 +2 位作者 吴珍珍 姚鹏 石晓勇 《Chinese Journal of Oceanology and Limnology》 CSCD 2015年第4期878-889,共12页
The feasibility of using fluorescence excitation-emission matrix(EEM) along with parallel factor analysis(PARAFAC) and nonnegative least squares(NNLS) method for the differentiation of phytoplankton taxonomic groups w... The feasibility of using fluorescence excitation-emission matrix(EEM) along with parallel factor analysis(PARAFAC) and nonnegative least squares(NNLS) method for the differentiation of phytoplankton taxonomic groups was investigated. Forty-one phytoplankton species belonging to 28 genera of five divisions were studied. First, the PARAFAC model was applied to EEMs, and 15 fluorescence components were generated. Second, 15 fluorescence components were found to have a strong discriminating capability based on Bayesian discriminant analysis(BDA). Third, all spectra of the fluorescence component compositions for the 41 phytoplankton species were spectrographically sorted into 61 reference spectra using hierarchical cluster analysis(HCA), and then, the reference spectra were used to establish a database. Finally, the phytoplankton taxonomic groups was differentiated by the reference spectra database using the NNLS method. The five phytoplankton groups were differentiated with the correct discrimination ratios(CDRs) of 100% for single-species samples at the division level. The CDRs for the mixtures were above 91% for the dominant phytoplankton species and above 73% for the subdominant phytoplankton species. Sixteen of the 85 field samples collected from the Changjiang River estuary were analyzed by both HPLC-CHEMTAX and the fluorometric technique developed. The results of both methods reveal that Bacillariophyta was the dominant algal group in these 16 samples and that the subdominant algal groups comprised Dinophyta, Chlorophyta and Cryptophyta. The differentiation results by the fluorometric technique were in good agreement with those from HPLC-CHEMTAX. The results indicate that the fluorometric technique could differentiate algal taxonomic groups accurately at the division level. 展开更多
关键词 fluorescence excitation-emission matrix parallel factor analysis nonnegative least squares phytoplankton fluorescence components
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Simulated photo-degradation of dissolved organic matter in lakes revealed by three-dimensional excitation-emission matrix with regional integration and parallel factor analysis 认领 引用 被引量：6
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作者 Jin Zhang Fanhao Song +5 位作者 Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第4期310-320,共11页
Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with t... Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic models.In the FRI analysis,fulvic-like and humic-like materials were the main constituents for both BH-FDOM and HF-FDOM.Four individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after photo-degradation.The multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(Radj2)(0.963-0.998).The photo-degradation rate constants(kn) showed differences of three orders of magnitude,from 1.09 × 10-6 to 4.02 × 10-4 min-1,and half-life of multi-order model(T1/2n)ranged from 5.26 to 64.01 min.The decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(PⅠ,n) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(PⅡ,n,while the largest decrease ratio was found for C3 components,and the lowest T1/2n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during photodegradation.This research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM. 展开更多
关键词 Fluorescent dissolved organic matter Photo-degradation Fluorescence regional integration Parallel factor analysis Three-dimensional excitationemission matrix Multi-order kinetic models
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A Comprehensive Review of Parallel Optimization Algorithms for High-Dimensional and Incomplete Matrix Factorization 认领 引用
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作者 Qicong Hu Hao Wu Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2025年第12期2399-2426,共28页
High-dimensional and incomplete(HDI) matrices are commonly encountered in various big data-related applications for illustrating the complex interactions among numerous entities, like the user-item interactions in a c... High-dimensional and incomplete(HDI) matrices are commonly encountered in various big data-related applications for illustrating the complex interactions among numerous entities, like the user-item interactions in a commercial recommender system or the user-user interactions in a social network services system. The factorization of such an HDI matrix can embed the involved entities into the low-dimensional feature space for acquiring their principal representation, which is a vital task in various application scenes and is often established through the Latent Factor Analysis(LFA). Nevertheless, an HDI matrix can be huge when the corresponding application explodes to involve millions of users, items, or other interactive nodes. In this case, a parallel optimization algorithm is desired for raising the scalability and time efficiency of an LFA model. This paper provides a comprehensive review of the existing parallel optimization algorithms for the LFA model. Specifically, it performs: 1) discussion and summary of these algorithms based on computing architecture and mode, 2) empirical studies of representative models, and3) summary of the current challenges and future directions in this domain. This survey aims to offer an exhaustive review of Parallel Optimization Algorithms for High-Dimensional and Incomplete Matrix Factorization, thereby fostering further research in this field. 展开更多
关键词 Data-related application high-dimensional and incomplete(HDI)data high-performance computing latent feature analysis(LFA) matrix factorization parallel optimization algorithm
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Discrimination of marine algal taxonomic groups based on fluorescence excitation emission matrix, parallel factor analysis and CHEMTAX 认领 引用 被引量：1
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作者 CHEN Xiaona SU Rongguo +2 位作者 BAI Ying SHI Xiaoyong YANG Rujun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第12期192-205,共14页
An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor analysis （PARAFAC） and CHEMTAX. The PARAFAC model was applied to fluo-rescence exc... An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor analysis （PARAFAC） and CHEMTAX. The PARAFAC model was applied to fluo-rescence excitation-emission matrix （EEM） of 60 algae species belonging to five divisions and 11 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. By the 11 fluorescent components, the algae species at different growth stages were classified correctly at the division level using Bayesian discriminant analysis （BDA）. Then the reference fluo-rescent component ratio matrix was constructed for CHEMTAX, and the EEM-PARAFAC-CHEMTAX method was developed to differentiate algae taxonomic groups. The correct discrimination ratios （CDRs） when the fluorometric method was used for single-species samples were 100% at the division level, except for Bacil-lariophyta with a CDR of 95.6%. The CDRs for the mixtures were above 94.0% for the dominant algae species and above 87.0% for the subdominant algae species. However, the CDRs of the subdominant algae species were too low to be unreliable when the relative abundance estimated was less than 15.0%. The fluorometric method was tested using the samples from the Jiaozhou Bay and the mesocosm experiments in the Xiaomai Island Bay in August 2007. The discrimination results of the dominant algae groups agreed with microscopy cell counts, as well as the subdominant algae groups of which the estimated relative abundance was above 15.0%. This technique would be of great aid when low-cost and rapid analysis is needed for samples in a large batch. The fluorometric technique has the ability to correctly identify dominant species with proper abundance both in vivo and in situ. 展开更多
关键词 CHEMTAX fluorescence excitatiqn-emission matrices in vivo fluorescent components,parallel factor analysis phytoplankton
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基于EEM-PARAFAC方法的北方典型城市溢流污染溯源研究 认领 引用
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作者 张贵鹏 袁鹏 +3 位作者 胡成 李亚峰 刘佳驹 杨康达 《水电能源科学》 北大核心 2026年第1期57-61,共5页
当前,城市雨季溢流污染已成为制约城市水环境质量提升的关键因素之一。开展溢流污染溯源研究,对于揭示污染物输出规律及实现溢流污染的精准控制具有重要意义。为此,以北京市清河沿岸某典型合流制排水分区为例,针对2024年7月单次降雨过... 当前,城市雨季溢流污染已成为制约城市水环境质量提升的关键因素之一。开展溢流污染溯源研究,对于揭示污染物输出规律及实现溢流污染的精准控制具有重要意义。为此,以北京市清河沿岸某典型合流制排水分区为例,针对2024年7月单次降雨过程中溢流口的溢流污水及附近区域地表径流进行了水质采样与系统监测,并采用三维荧光光谱(3D-EEM)结合平行因子分析(PARAFAC)方法,对溢流污水中溶解性有机质(DOM)的来源进行了溯源分析。结果表明,降雨初期地表径流中的污染物浓度高于溢流污水,但随着降雨的持续,地表径流污染物浓度逐渐降低并最终低于溢流污水。溢流污水中检测出三种荧光组分,分别为类富里酸组分C1、氨基酸和类腐殖质混合物混合组分C2及类酪氨酸组分C3,其占总荧光组分的比例分别为37.20%、49.29%和13.51%。溯源分析进一步表明,管道沉积物对溢流污水中DOM的贡献率最大,是其主要来源。 展开更多
关键词 地表径流 溢流污水 平行因子分析 三维荧光光谱 溯源分析
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基于EEM-PARAFAC-机器学习的变温期藻源嗅味风险预测 认领 引用
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作者 俞慧影 吴庆余 +4 位作者 梁嘉豪 郑国庆 邱怡敏 温馨 岑程 《宁波大学学报（理工版）》 CAS 2026年第4期102-110,共9页
针对藻源性嗅味物质(如β-环柠檬醛)随温度快速波动、常规气相色谱-质谱检测频次不足的问题,探索三维荧光光谱快速预测藻源嗅味总负荷的可行性。本文以铜绿微囊藻(Microcystis aeruginosa)变温培养体系为对象,定义总嗅味指标表征综合嗅... 针对藻源性嗅味物质(如β-环柠檬醛)随温度快速波动、常规气相色谱-质谱检测频次不足的问题,探索三维荧光光谱快速预测藻源嗅味总负荷的可行性。本文以铜绿微囊藻(Microcystis aeruginosa)变温培养体系为对象,定义总嗅味指标表征综合嗅味负荷,构建平行因子分析荧光组分及多维输入特征,系统比较18种回归模型,并对最优模型开展可解释性分析。结果表明,PARAFAC四组分方案兼顾92.2%解释方差与0.997拆半相似度;调优后XGBoost在独立测试集上R2=0.882、RMSE=0.732、MAE=0.426;置换重要性与SHAP等多种方法一致识别培养时间、D峰和C峰为前三位主控因子(累计贡献55.4%)。 展开更多
关键词 三维荧光光谱 平行因子分析 XGBoost 藻源性嗅味 可解释机器学习
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基于3DEEMs-PARAFAC的长荡湖溶解性有机物(DOM)来源及分布特征研究 认领 引用 被引量：2
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作者 宦娟 郑永春 +4 位作者 徐宪根 张浩 袁佳龙 李鑫城 周立万 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2025年第2期591-600,共10页
湖泊水质直接影响周边生态、人类健康和经济,而现代工业、城市化带来的压力使得湖泊面临着严峻挑战,需要深入了解变化、寻找污染源,并采取有效措施维护生态健康和人民生活水质安全。因此,基于三维荧光(3DEEMs)和平行因子(PARAFAC)方法,... 湖泊水质直接影响周边生态、人类健康和经济,而现代工业、城市化带来的压力使得湖泊面临着严峻挑战,需要深入了解变化、寻找污染源,并采取有效措施维护生态健康和人民生活水质安全。因此,基于三维荧光(3DEEMs)和平行因子(PARAFAC)方法,对2022年长荡湖及其周边面源的水质溶解性有机物(DOM)的荧光光谱进行分析,探讨了长荡湖DOM的荧光组分来源及时空分布,同时对比周边面源荧光与湖体荧光的相似性。结果表明,长荡湖水体的溶解有机质(DOM)荧光主要由两类荧光组分构成:类蛋白荧光组分(C1)和类腐殖质组分(C2、C3、C4)。这些组分与周边印染、生活排放以及水产养殖等源头的荧光组分相似度较高。长荡湖在不同水期各类荧光分布存在差异,特别是丰水期,荧光强度主要集中于下游出湖口。长荡湖荧光特征参数FI的值为(1.68~1.75),BIX的值在(0.92~0.93),HIX的值在(0.56~0.7),表明长荡湖DOM的增量以内源为主。综合分析显示,长荡湖的有机质主要来自水生动植物和藻类的腐解等内源增量。冗余分析结果表明,与湖体DOM相关性较大的环境因子主要包括Chl-a和COD。本研究不仅对解决当地生态环境问题具有积极作用,同时也为其他湖泊生态系统的研究提供了有价值的实践经验。 展开更多
关键词 长荡湖 三维荧光 平行因子分析 DOM时空分布 有机污染
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Fast parallel factor decomposition technique for coherently distributed source localization 认领 引用 被引量：2
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作者 CHENG Qianlin ZHANG Xiaofei CAO Renzheng 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2018年第4期667-675,共9页
This paper links parallel factor（PARAFAC） analysis to the problem of nominal direction-of-arrival（DOA） estimation for coherently distributed（CD） sources and proposes a fast PARAFACbased algorithm by establishing... This paper links parallel factor（PARAFAC） analysis to the problem of nominal direction-of-arrival（DOA） estimation for coherently distributed（CD） sources and proposes a fast PARAFACbased algorithm by establishing the trilinear PARAFAC model.Relying on the uniqueness of the low-rank three-way array decomposition and the trilinear alternating least squares regression, the proposed algorithm achieves nominal DOA estimation and outperforms the conventional estimation of signal parameter via rotational technique CD（ESPRIT-CD） and propagator method CD（PM-CD）methods in terms of estimation accuracy. Furthermore, by means of the initialization via the propagator method, this paper accelerates the convergence procedure of the proposed algorithm with no estimation performance degradation. In addition, the proposed algorithm can be directly applied to the multiple-source scenario,where sources have different angular distribution shapes. Numerical simulation results corroborate the effectiveness and superiority of the proposed fast PARAFAC-based algorithm. 展开更多
关键词 source localization coherently distributed （CD）source parallel factor analysis propagator method （PM） trilin-ear decomposition
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Attitude estimation for spacecraft docking based on EMVS array via PARAFAC algorithm 认领 引用
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作者 LIU Bingqi CHEN Guangdong +1 位作者 LIU Zhuhang SONG He 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2025年第3期623-633,共11页
A spacecraft attitude estimation method based on electromagnetic vector sensors(EMVS)array is proposed,which employs the orthogonally constrained parallel factor(PARAFAC)algorithm and makes use of measurements of the ... A spacecraft attitude estimation method based on electromagnetic vector sensors(EMVS)array is proposed,which employs the orthogonally constrained parallel factor(PARAFAC)algorithm and makes use of measurements of the two-dimensional direction-of-arrival(2D-DOA)and polarization angles,aiming to address the issues of incomplete,asynchronous,and inaccurate third-party reference used for attitude estimation in spacecraft docking missions by employing the electromagnetic wave’s three-dimensional(3D)wave structure as a complete third-party reference.Comparative analysis with state-ofthe-art algorithms shows significant improvements in estimation accuracy and computational efficiency with this algorithm.Numerical simulations have verified the effectiveness and superiority of this method.A high-precision,reliable,and cost-effective method for rapid spacecraft attitude estimation is provided in this paper. 展开更多
关键词 parallel factor(PARAFAC)analysis electromagnetic vector sensors attitude estimation state of polarization spacecraft docking
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基于PARAFAC和BP的齿轮裂纹故障诊断方法 认领 引用
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作者 梁晓培 李少义 +3 位作者 吴坚 易怀胜 王志刚 陈汉新 《传动技术（中英文）》 2025年第2期15-22,共8页
以平行因子分析理论为基础,将原始信号经小波分解构造三阶张量,再通过平行因子分解得到信号的空间加载因子、频率加载因子和时间加载因子,频率加载因子和时间加载因子可以明显表征齿轮箱裂纹的状态,以此进行特征提取构造特征向量映射不... 以平行因子分析理论为基础,将原始信号经小波分解构造三阶张量,再通过平行因子分解得到信号的空间加载因子、频率加载因子和时间加载因子,频率加载因子和时间加载因子可以明显表征齿轮箱裂纹的状态,以此进行特征提取构造特征向量映射不同齿轮裂纹的工况与特征信息,并将其作为波搜索算法优化后的BP神经网络模型的特征向量进行故障分类识别。与时频域信息特征提取方法相比较,所提出的方法用于齿轮裂纹故障诊断时稳定性更强,所构造的分类器模型准确度更高,且模型复杂度没有明显变化。 展开更多
关键词 故障诊断 平行因子分析 齿轮裂纹 BP神经网络
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不同空间尺度景观格局对丹江流域溶解性有机质的影响 认领 引用 被引量：1
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作者 陈新 徐国策 +5 位作者 王芸 任宗萍 万顺 赵梦圆 谷丰佑 张腾飞 《环境科学》 EI CAS CSCD 北大核心 2026年第5期2964-2978,共15页
景观格局会影响河流生态系统的生物地球化学循环.丹江流域是南水北调中线工程的重要水源地,探究景观格局对径流溶解性有机质(DOM)的影响对流域生态保护具有重要意义.基于平水期(2023年11月)、枯水期(2024年3月)及丰水期(2024年7月)野外... 景观格局会影响河流生态系统的生物地球化学循环.丹江流域是南水北调中线工程的重要水源地,探究景观格局对径流溶解性有机质(DOM)的影响对流域生态保护具有重要意义.基于平水期(2023年11月)、枯水期(2024年3月)及丰水期(2024年7月)野外采样数据,通过三维荧光-平行因子法(EEM-PARAFAC),解析了丹江流域径流DOM的时空变化特征,并运用随机森林模型、冗余分析(RDA)和方差分解分析(VPA)方法,量化了景观格局和水化学对DOM的影响.结果表明,丹江流域径流中ρ[溶解性有机碳(DOC)]均值为5.03 mg·L-1,变化范围为2.59~9.96 mg·L-1,浓度大小为:丰水期(5.80 mg·L-1)>枯水期(5.28 mg·L-1)>平水期(4.02 mg·L-1).平水期和丰水期DOM组分以类腐殖质为主,相对丰度分别为67.07%和79.45%,枯水期DOM中类腐殖质和类蛋白质相对丰度分别为49.21%和50.79%.丰水期和平水期水体DOM表现出更强的外源特征,枯水期水体DOM表现出更明显的自生源特征.景观格局对DOC浓度和DOM组分影响最大的时空尺度分别是枯水期500 m圆形缓冲区和丰水期200 m圆形缓冲区.建设用地、氨氮和斑块聚集指数是驱动DOC浓度变化的主要因子.水化学水温、电导率、总磷与土地利用林地、草地、农地及景观配置聚合度指数、连续度指数是影响丹江流域径流DOM组分变化的显著影响因子.研究结果可为土地利用合理规划提供可靠数据,并为丹江流域水环境管理提供参考. 展开更多
关键词 景观格局 溶解性有机质(DOM) 平行因子分析 径流 丹江
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Optical properties of soil water-extractable organic matter respond to changes in irrigation water quality 认领 引用
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作者 Mikhail BORISOVER Asher BAR-TAL +3 位作者 Nadezhda BUKHANOVSKY Anna BEREZKIN Marcos LADO Guy J.LEVY 《Pedosphere》 SCIE CAS CSCD 2026年第2期638-654,共17页
Treated wastewater(TWW)irrigation may harm soil and agricultural production.Adverse effects of TWW irrigation may be mitigated by changing irrigation water quality,e.g.,use of fresh water(FW),or management,e.g.,lower-... Treated wastewater(TWW)irrigation may harm soil and agricultural production.Adverse effects of TWW irrigation may be mitigated by changing irrigation water quality,e.g.,use of fresh water(FW),or management,e.g.,lower-frequency irrigation(LFI)with TWW.The influence of mitigation treatments on soil organic matter and water-extractable organic matter is unknown.To examine this influence,a study was conducted in an avocado orchard irrigated from 2009 with secondary TWW.Four parallel treatments were applied for six years(2016-2021),involving irrigation with FW,a 1:1 FW-TWW mixture,TWW at LFI(twice a week),and TWW irrigation three times a week as control.Soil samples from three depths were characterized for total organic and inorganic carbon and nitrogen and using Fourier-transform infrared spectra that were decomposed into components by nonnegative matrix factorization.Aqueous extracts of soil samples were characterized for dissolved organic carbon(DOC),inorganic carbon,and nitrogen concentrations,absorbance at254 nm(Abs254),and excitation-emission matrices of fluorescence that were decomposed into components by parallel factor analysis.The Abs254 and fluorescence of humic-like components in the soil extracts were the attributes most consistently responding to irrigation water quality.Irrigation with FW and a 1:1 FW-TWW mixture led to decreases in the concentrations of aromatic and humic-like constituents in the soil extracts compared with the control TWW irrigation.Changing soil irrigation management had no or little impact on those attributes compared with the control TWW irrigation.Results of the study support the use of optical properties related to the concentrations of ultraviolet-absorbing and light-emitting constituents in soil extracts,rather than the whole DOC concentration,as sensitive descriptors suitable for evaluating soil response in different agricultural scenarios. 展开更多
关键词 fluorescence Fourier-transform infrared spectroscopy humic-like substances nonnegative matrix factorization parallel factor analysis specific ultraviolet absorbance treated wastewater
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基于特征激发波长提取的三维荧光光谱水污染溯源效率优化研究 认领 引用 被引量：1
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作者 赵远 唐琪 +4 位作者 匡立涛 金梦 兰亚琼 徐灿灿 刘锐 《环境化学》 CAS CSCD 北大核心 2026年第5期2237-2250,共14页
针对传统三维荧光光谱(EEM)扫描耗时长、数据冗余、仪器成本高且笨重的问题,并结合现场快速水污染溯源需求,本研究提出了一种基于固定特征激发波长扫描与支持向量机(SVM)相结合的新型分类识别方法,为水污染溯源提供高效解决方案.收集并... 针对传统三维荧光光谱(EEM)扫描耗时长、数据冗余、仪器成本高且笨重的问题,并结合现场快速水污染溯源需求,本研究提出了一种基于固定特征激发波长扫描与支持向量机(SVM)相结合的新型分类识别方法,为水污染溯源提供高效解决方案.收集并检测来自化纤染整、毛纺织染整、皮革加工、金属表面加工、造纸以及生活污水在内的180个样本EEM数据.利用平行因子分析(PARAFAC)解析得到特征组分,确定特征激发波长,并结合相关性分析和特征重要性分析,筛选出7条特征激发波长.随后,基于这7条特征激发波长与原始EEM数据分别构建SVM和随机森林(RF)识别模型进行性能比较和评估.结果表明,相较于传统EEM扫描所获得的原始数据集,特征激发波长数据集的识别模型在保持较高识别准确率的同时,显著提升了识别效率;其中SVM的表现最为出色,模型运行时间由243.05 s降至34.56 s(降幅86%),识别准确率高达94.4%.此外,精确率、召回率和F1-score等指标上也验证了SVM结合特征激发波长的良好性能,尤其是在金属表面加工废水的识别中表现突出.本研究通过简化EEM扫描方法并结合SVM模型,为水体污染的快速溯源提供了一种高效可靠的技术方法,具有较高的应用价值.未来将进一步优化特征筛选策略,并探索更多样本类别与模型组合,以拓展更多应用场景. 展开更多
关键词 水污染溯源 三维荧光光谱 特征激发波长 支持向量机 随机森林 平行因子分析
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中小流域DOM来源的3D-EEMs-PARAFAC解析 认领 引用
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作者 冯轩成 王宸奥 +2 位作者 许世豪 钟惠舟 李芳 《中国给水排水》 CAS CSCD 北大核心 2025年第23期84-90,共7页
溶解性有机物(DOM)是较好的污染物溯源指标,可为流域水环境治理措施制定提供理论依据。为揭示中小流域水体的DOM特征及来源,采集源头型、近郊型、城镇型三类河流水体的38个样品,采用三维荧光光谱参数(FI、BIX、HIX、β∶α)、三维荧光光... 溶解性有机物(DOM)是较好的污染物溯源指标,可为流域水环境治理措施制定提供理论依据。为揭示中小流域水体的DOM特征及来源,采集源头型、近郊型、城镇型三类河流水体的38个样品,采用三维荧光光谱参数(FI、BIX、HIX、β∶α)、三维荧光光谱-平行因子(3D-EEMsPARAFAC)模型对DOM荧光特征进行分析。结果表明,FI、BIX、HIX、β∶α的范围分别为1.29~3.51、0.75~2.34、0.03~0.56、0.72~2.08,DOM主要为自生源,生物源组分占比较高,腐殖化程度较低,微生物活性较高。PARAFAC解析出5种组分:类色氨酸(C1)、芳香蛋白和可溶性微生物代谢产物(C2和C4)、胡敏酸(C3)、类酪氨酸(C5),其中C1、C2、C4、C5占总荧光强度的89.96%。源头型河流的DOM主要组分为芳香蛋白和可溶性微生物代谢产物(占比约54.03%);近郊型河流的DOM主要组分为类色氨酸、类酪氨酸(占比约70.78%);城镇型河流的DOM主要组分为芳香蛋白、可溶性微生物代谢产物、类酪氨酸(占比约79.78%)。根据DOM组分来源,可制定针对性的流域水环境治理措施。 展开更多
关键词 中小流域 溶解性有机物 三维荧光光谱 平行因子分析 荧光吸收峰
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城市河流排口水体溶解性有机质(DOM)季节变化及其与水质的联系—以合肥市南淝河-板桥河为例 认领 引用
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作者 唐晓先 尹浩杰 +4 位作者 陈希子 熊竹阳 张宪良 胡家伟 黄涛 《环境化学》 CAS CSCD 北大核心 2026年第6期2682-2692,共11页
于2023—2024年度,分季节采集、分析合肥市南淝河-板桥河选定排口排水的溶解性有机质(dissolved organic matter,DOM)和水质变化.通过水体DOM的三维荧光光谱-平行因子分析得到3种荧光组分,分别为紫外光区类富里酸C1、类色氨酸(类蛋白)C... 于2023—2024年度,分季节采集、分析合肥市南淝河-板桥河选定排口排水的溶解性有机质(dissolved organic matter,DOM)和水质变化.通过水体DOM的三维荧光光谱-平行因子分析得到3种荧光组分,分别为紫外光区类富里酸C1、类色氨酸(类蛋白)C2和陆源类腐殖质C3.南淝河-板桥河排口水体DOM荧光组分季节变化明显,冬春季类蛋白组分C2占比高于夏秋季,主要源于夏秋季(丰水期)雨水稀释和城市面源径流输入的影响.夏秋季排口水质指标浓度降低,主要受到丰水期雨水稀释的影响.排口水体DOM荧光指数和生物源指数分别大于1.9和1.0,表明DOM以自生源为主.夏秋季排口排水DOM腐殖化指数、紫外比吸收系数升高,光谱斜率比值降低,指示降雨引入更多城市面源径流的影响.南淝河-板桥河排口水体DOM的类蛋白组分C2和陆源类腐殖质组分C3与水质指标均呈显著正相关,可精确指示城市面源径流和生活污水对排口水体污染来源及其水质季节变化的影响,为后续开展排口综合治理提供了科学依据. 展开更多
关键词 城市河流 排口 溶解性有机质 平行因子分析 荧光组分
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玉米秸秆还田方式对土壤胡敏酸含量及组分的影响 认领 引用
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作者 高盼 蔡姗姗 +5 位作者 张巩亮 徐莹莹 杨慧莹 王宇先 申惠波 腾思远 《中国土壤与肥料》 CAS CSCD 北大核心 2026年第4期42-52,共11页
为探究不同秸秆还田方式对土壤胡敏酸含量及结构特征的影响,以长期(8年)秸秆还田的农田土壤为研究对象,设置无秸秆还田(CK)、秸秆覆盖还田(NTS)、秸秆翻埋还田(BTS)和秸秆碎混还田(MTS)处理,通过三维荧光光谱和平行因子分析方法相结合,... 为探究不同秸秆还田方式对土壤胡敏酸含量及结构特征的影响,以长期(8年)秸秆还田的农田土壤为研究对象,设置无秸秆还田(CK)、秸秆覆盖还田(NTS)、秸秆翻埋还田(BTS)和秸秆碎混还田(MTS)处理,通过三维荧光光谱和平行因子分析方法相结合,研究不同秸秆还田方式下土壤胡敏酸荧光光谱特征。结果表明,不同秸秆还田方式均有利于表土层(0~10和10~20 cm)胡敏酸含量的积累。NTS处理显著提高了0~10 cm土层胡敏酸含量(35.25%),而BTS处理在10~20 cm土层胡敏酸含量累积最佳(9.80%)。三维荧光光谱分析发现,土壤胡敏酸受自生源和外生源共同作用的影响,呈现强腐殖化特征。运用平行因子分析共识别出C1、C3、C4(腐殖酸类物质)和C2(富里酸类物质)4个荧光组分;3个秸秆还田处理表现出秸秆富集层土壤腐殖化程度更高。综上,不同秸秆还田方式显著影响各土层的土壤胡敏酸含量,进而影响不同土层土壤胡敏酸结构及组分。本研究结果为探明半干旱黑土区秸秆还田方式对胡敏酸含量及组分的影响提供了理论依据。 展开更多
关键词 秸秆还田方式 土壤胡敏酸 三维荧光光谱 平行因子分析
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一种稳健的互质空间步进频雷达参数估计方法 认领 引用
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作者 贺顺 李梦瑶 杨志伟 《雷达科学与技术》 北大核心 2026年第3期308-319,共12页
互质空间步进频雷达通过构建虚拟孔径并合成等效大带宽,有效提升了角度与距离分辨率。然而,传统方法通过对样本协方差矩阵进行向量化来获取虚拟阵列数据时,会破坏接收信号在发射-接收-快拍维的固有结构,导致信息损失。尽管基于张量平行... 互质空间步进频雷达通过构建虚拟孔径并合成等效大带宽,有效提升了角度与距离分辨率。然而,传统方法通过对样本协方差矩阵进行向量化来获取虚拟阵列数据时,会破坏接收信号在发射-接收-快拍维的固有结构,导致信息损失。尽管基于张量平行因子分解的方法能够保留信号的三维结构,但其分解误差会在后续的互质阵虚拟化过程中被放大,从而影响参数估计的性能。为此,本文提出了一种基于Hankel矩阵重构的稳健参数估计方法。该方法首先构建接收信号的三阶张量模型,并引入了快拍维低秩近似以降低计算复杂度;随后,针对张量分解误差的放大问题,将虚拟导向矢量的估计值重构为Hankel矩阵,并结合截断奇异值分解,有效修正了导向矢量的估计偏差。仿真结果表明,在低信噪比和小快拍条件下,所提方法相较于2D-SSMUSIC、PARAFAC以及HOSVD-RDMUSIC算法,具有更高的估计精度和鲁棒性,且计算复杂度更低。 展开更多
关键词 互质空间步进频雷达 平行因子分解 Hankel矩阵重构 截断奇异值分解 误差抑制
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十五里河水体中DOM三维荧光特征及其来源解析 认领 引用
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作者 程雨涵 宋雨佩 《中国给水排水》 CAS CSCD 北大核心 2026年第11期59-65,共7页
利用三维荧光平行因子分析(EEMs-PARAFAC)模型研究十五里河水体溶解性有机物(DOM)的组分、荧光强度和可能来源,并探究DOM与COD、N、P浓度之间的相关性。结果表明,十五里河水体中的DOM主要有3种组分,分别为陆生源类腐殖质C1(240、320 nm/... 利用三维荧光平行因子分析(EEMs-PARAFAC)模型研究十五里河水体溶解性有机物(DOM)的组分、荧光强度和可能来源,并探究DOM与COD、N、P浓度之间的相关性。结果表明,十五里河水体中的DOM主要有3种组分,分别为陆生源类腐殖质C1(240、320 nm/405 nm)、自生源类腐殖质C2(225、265 nm/325、385、450 nm)和类色氨酸蛋白质C3(230、250 nm/250、340、410 nm),类腐殖质的占比最大,为67%,且C2和C3组分具有同源性。类腐殖质组分从上游至下游呈先上升后下降再上升趋势。结合荧光指数(FI)、自生源指数(BIX)、腐殖化指数(HIX)及新鲜度指数(β∶α)等各项荧光指标的分析发现,DOM浓度主要受陆生源影响,对DOM的影响高达40%。由DOM各荧光组分与营养物质的相关性分析结果可知,C1和C3组分与N、P等营养物质均呈正相关(p<0.05),说明DOM可以在一定程度上指示十五里河水体富营养化水平。此外,十五里河水体DOM各荧光组分与COD均具有正相关性(p<0.05),能通过DOM特征推演出COD浓度。 展开更多
关键词 十五里河 溶解性有机物 三维荧光分析 平行因子分析
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Comparison of the K1 Rule,Parallel Analysis,and the Bass-Ackward Method on Identifying the Number of Factors in Factor Analysis 认领 引用
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作者 Lingbo Tong Wen Qu Zhiyong Zhang 《Fudan Journal of the Humanities and Social Sciences》 2025年第1期17-44,共28页
Factor analysis is widely utilized to identify latent factors underlying the observed variables.This paper presents a comprehensive comparative study of two widely used methods for determining the optimal number of fa... Factor analysis is widely utilized to identify latent factors underlying the observed variables.This paper presents a comprehensive comparative study of two widely used methods for determining the optimal number of factors in factor analysis,the K1 rule,and parallel analysis,along with a more recently developed method,the bass-ackward method.We provide an in-depth exploration of these techniques,discussing their historical development,advantages,and limitations.Using a series of Monte Carlo simulations,we assess the efficacy of these methods in accurately determining the appropriate number of factors.Specifically,we examine two cessation criteria within the bass-ackward framework:BA-maxLoading and BA-cutoff.Our findings offer nuanced insights into the performance of these methods under various conditions,illuminating their respective advantages and potential pitfalls.To enhance accessibility,we create an online visualization tool tailored to the factor structures generated by the bass-ackward method.This research enriches the understanding of factor analysis methodology,assists researchers in method selection,and facilitates comprehensive interpretation of latent factor structures. 展开更多
关键词 Exploratory factor analysis Number of factors Bass-ackward method Parallel analysis K1 rule
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