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Characterization of dissolved organic matter fluorescence in the South Atlantic Bight with use of parafac model: Relationships between fluorescence and its components, absorption coefficients and organic carbon concentrations

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MARINE CHEMISTRY 2010年第1-2期118卷 22-36页

作者： Kowalczuk, Piotr Cooper, William J. Durako, Michael J. Kahn, Amanda E. Gonsior, Michael Young, Heather Polish Acad Sci Inst Oceanol PL-81712 Sopot Poland Univ Calif Irvine Urban Water Res Ctr Irvine CA 92697 USA Univ Calif Irvine Dept Civil & Environm Engn Irvine CA 92697 USA Univ N Carolina Wilmington Ctr Marine Sci Wilmington NC 28409 USA

In this study, the CDOM absorption coefficient at 350 nm [a(CDOM)(350)] and CDOM excitation emission matrix (EEM) fluorescence were used to estimate annual fluxes of dissolved organic carbon (DOC) from the Cape Fear River to Long Bay in the South Atlantic Bight. Water samples were collected during a 3.5 year period, from October 2001 through March 2005. in the vicinity of the Cape Fear River (CFR) outlet and adjacent Onslow Bay (OB). Parallel factor analysis (parafac) of CDOM EEM spectra identified six components: three terrestrial humic-like, one marine humic-like and two protein-like. Empirical relationships were derived from the parafac model between DOC concentration and a(CDOM)(350). total fluorescence intensity and the intensities of respective EEM components. DOC concentration and CDOM optical parameters were very well correlated and R(2) values ranged from 0.77 to 0.90. Regression analyses revealed that the non-absorbing DOC fraction, in DOC concentration estimated from CDOM optical parameters, varied with the qualitative composition of the COOK DOC concentration and intensity of the humic-like CDOM components c by excitation maxima at longer wavelengths have significantly higher estimated non-absorbing DOC compared to the analogous relationships between DOC and intensity of the humic-like CDOM components characterized by excitation maxima at shorter wavelengths. The relationships between DOC concentration and intensity of one of the protein-like components resulted in significantly reduced non-absorbing DOC fraction in DOC concentration estimation. Results of regression analyses between fluorescence intensities of specific EEM components and CDOM-specific absorption coefficients suggest that the relative proportion of humic-like CDOM components (characterized by excitation maximum at longer wavelengths) and the main protein-like component have the most impact on the values of a(CDOM)*(350). Based on the relationships between a(CDOM)(350), Cape Fear River fl

关键词： Chromophoric dissolved organic matter Absorption Fluorescence Excitation emission Matrix parafac model Dissolved organic carbon Organic carbon flux South Atlantic Bight

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Characterization of dissolved organic matter fluorescence in the South Atlantic Bight with use of parafac model: Interannual variability

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MARINE CHEMISTRY 2009年第3-4期113卷 182-196页

作者： Kowalczuk, Piotr Durako, Michael J. Young, Heather Kahn, Amanda E. Cooper, William J. Gonsior, Michael Polish Acad Sci Inst Oceanol PL-81712 Sopot Poland Univ N Carolina Ctr Marine Sci Wilmington NC 28409 USA Univ Calif Irvine Urban Water Res Ctr Irvine CA 92697 USA Univ Calif Irvine Dept Civil & Environm Engn Irvine CA 92697 USA

Systematic water sampling for characterization of chromophoric dissolved organic matter (CDOM) in the coastal South Atlantic Bight, was conducted as part of the long term Coastal Ocean Research and Monitoring Program (CORMP). Water samples were collected during a 3.5 year period, from October 2001 until March 2005, in the vicinity of the Cape Fear River (CFR) outlet and in adjacent Onslow Bay (OB). During this study there were two divergent hydrological and meteorological conditions in the CFR drainage area: a severe drought in 2002, followed by the very wet year of 2003. CDOM was characterized optically by the absorption coefficient at 350 rim, the spectral slope coefficient (S), and by Excitation Emission Matrix (EEM) fluorescence. Parallel Factor Analysis (parafac) was used to assess CDOM composition from EEM spectra and six components were identified: three terrestrial humic-like components, one marine humic-like component and two protein-like components. Terrestrial humic-like components contributed most to dissolved organic matter (DOM) fluorescence in the low salinity plume of the CFR. The contribution of terrestrial humic-like components to DOM fluorescence in OB was much smaller than in the CFR plume area. Protein-like components contributed significantly to DOM fluorescence in the coastal ocean of OB and they dominated DOM fluorescence in the Gulf Stream waters. Hydrological conditions during the observation period significantly impacted both concentration and composition of CDOM found in the estuary and coastal ocean. In the CFR plume, there was an order of magnitude difference in CDOM absorption and fluorescence intensity between samples collected during the drought compared to the wet period. During the drought, CDOM in the CFR plume was composed of equal proportions of terrestrial humic-like components (ca. 60% of the total fluorescence intensity) with a significant contribution of proteinaceous substances (ca. 20% of the total fluorescence). During hi

关键词： Chromophoric dissolved organic matter Fluorescence Excitation Emission Matrix parafac model Inter-annul variability South Atlantic Bight

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Structure Constrained parafac model with Application to Signal Processing

Structure Constrained PARAFAC Model with Application to Sign...

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International Symposium on Knowledge Acquisition and modeling

作者： Liu, Xu Xu, Zongze Nanjing Univ Aeronaut & Astronaut Coll Info Sci & Tech Nanjing 210016 Peoples R China

ISBN: (纸本)9781424435296

Structure constrained PARAllel FACtor (parafac) model, which combines the structural property of communication signal with the parafac analysis, was presented in this paper. The uniqueness property of the model was discussed and developed. Structure constrained trilinear alternative least square (SCTALS) algorithm was proposed to fit the constrained model. Simulation results showed that, compared to the normal parafac model, the structure constrained parafac was more suitable to describe communication signal. The blind signal processing algorithm based on the constrained model had better fitting performance, and still worked well in some conditions where the normal parafac-based algorithm failed.

关键词： blind signal processing parafac model structure constraint uniqueness property

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Semi-Blind Receivers for Multi-User Massive MIMO Relay Systems Based on Block Tucker2-parafac Tensor model

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IEEE ACCESS 2020年 8卷 32170-32186页

作者： Du, Jianhe Han, Meng Jin, Libiao Hua, Yan Li, Xingwang Commun Univ China Sch Informat & Commun Engn Beijing 100024 Peoples R China Henan Polytech Univ Sch Phys & Elect Informat Engn Jiaozuo 454000 Henan Peoples R China

Massive multiple-input multiple-output (MIMO) relay can significantly improve the capacity and throughput of wireless networks, thus has been a sought-after technique for future communication systems. However, the development of massive MIMO relay systems faces several major challenges. For example, the knowledge of instantaneous channel state information (CSI) is needed to estimate signals and optimize systems. Traditional estimation schemes need to transmit pilot sequences, which occupy the spectrum resources. In this paper, we propose a tensor-based method for joint signal and channel estimation for multi-user massive MIMO relay systems without using pilot sequences, and develop two tensor-based semi-blind receivers. Through multidimensional signaling scheme, the signals received by each user are formulated as the block Tucker2-parafac (TP) tensor model. Then, two semi-blind receivers are proposed to jointly estimate the information signals and channel matrices. One is based on the tensor-based closed-form receiver, the other is based on the tensor-based iterative receiver. The proposed closed-form approach can also be used to initialize the iterative receiver for improving the convergence speed. In particular, the proposed schemes are practicable for both time division duplexing (TDD) and frequency division duplexing (FDD) modes. Uniqueness, identifiability and complexity are analyzed for our receivers. Compared with existing receivers, our receivers offer superior bit error rate (BER) and normalized mean square error (NMSE) performance. Numerical examples are shown to demonstrate the effectiveness of the proposed tensor-based receivers.

关键词： Massive MIMO cooperative communication block Tucker2 model parafac model signal and channel estimation

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Structure Constrained parafac model with Application to Signal Processing

Structure Constrained PARAFAC Model with Application to Sign...

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2008 IEEE International Symposium on Knowledge Acquisition and modeling Workshop(KAM 2008)

作者： Xu Liu College of Info.Sci.and Tech.,Nanjing Univ.of Aeronautics and Astronautics Nanjing ,ChinaZongze Xu College of Info.Sci.and Tech.,Nanjing Univ.of Aeronautics and Astronautics Nanjing ,China

Structure constrained PARAllel FACtor (parafac) model,which combines the structural property of communication signal with the parafac analysis,was presented in this *** uniqueness property of the model was discussed and *** constrained trilinear alternative least square (SCTALS) algorithm was proposed to fit the constrained *** results showed that,compared to the normal parafac model,the structure constrained parafac was more suitable to describe communication *** blind signal processing algorithm based on the constrained model had better fitting performance,and still worked well in some conditions where the normal parafac-based algorithm failed.

关键词： blind signal processing parafac model structure constraint uniqueness property

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Compressed parafac model-based Two-Dimensional Angle Estimation for Acoustic Vector-Sensor Arrays

Compressed PARAFAC Model-based Two-Dimensional Angle Estimat...

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2017 2nd International Conference on Machinery,Electronics and Control Simulation(MECS 2017)

作者： Le Xu You Sun Na Shi Xiaofei Zhang College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics State Key Laboratory of Millimeter Waves Southeast University National Mobile Communications Research Laboratory Southeast University

In this paper, in order to estimate the angles for arbitrarily spaced arrays with acoustic vector-sensor, we combine the compressed sensing theory with parallel factor(parafac) model, and propose a neoteric angle estimation algorithm. The proposed algorithm firstly compressed the parafac model, then exploit trilinear alternating least square(TALS) algorithm to estimate the parameter matrices and obtains the angle estimation. Owing to compression, the proposed algorithm has smaller storage requirement and lower computational complexity, compared with the conventional parafac algorithm. It's also works well to achieve automatically paired azimuth and elevation angles. The angle estimation performance of the proposed algorithm is close to the conventional parafac algorithm, and is better than the estimation of signal parameters via rotational invariance techniques(ESPRIT) algorithm. Various simulation results demonstrate the effectiveness of our algorithm.

关键词： arbitrary array acoustic vector-sensor compress parafac model angle estimation

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A prompt technique to identify fluoroquinolone antibiotics (FQs) residue in the environments

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METHODSX 2025年 14卷 103287页

作者： Niloy, Nahin Mostofa Parvin, Fahmida Tareq, Shafi M. Jahangirnagar Univ Dept Environm Sci Hydrobiogeochem & Pollut Control Lab Dhaka 1342 Bangladesh Southern Cross Univ Ctr Coastal Biogeochem Sch Environm Sci & Engn Lismore NSW Australia

The widely used fluoroquinolone (FQ) antibiotics have become emerging contaminants due to their unconstrained usage. A prompt, straightforward, pr & eacute;cised, and advanced technique named fluorescence spectroscopy was applied to characterize and semi-quantify FQs. However, excitation wavelengths on the comparable ranges of FQs and ubiquitous humic substance (HS) complicate their identification in the mixture. This study develops a simple spectral technique that affirms the individual identification of FQs and HS in the natural environment. The following characteristics and methods can demonstrate the traces of FQs in the environment center dot Presence of fluorophore at Excitation/Emission = 225-230/285-295 nm wavelength in excitation-emission matrix (EEM) and parallel factor analysis (parafac) models. center dot FQs and HS have fluorophores at excitation wavelengths of 275 nm and 325 nm in parafac analysis. Unlike HS, the notable spectral presence in < 350 nm emission during 275 nm excitation in FQs ensures their distinct identification in the mixture. center dot FQ affirming component intensity at Excitation/Emission = 225-230/285-295 nm and the intensity < 350 nm emission during 275 nm excitation are considered in conjunction to quantify the amount of least FQ in any environmental sample.

关键词： Fluoroquinolone antibiotics Fluorescence spectroscopy Humic substance Excitation-emission Matrix (EEM) parafac model

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Fluorescence data of natural organic matter in groundwater from the Fontaine de Vaucluse karst system (2020 to 2021): Excitation-emission matrix (EEM) and 2D spectra at 254 nm excitation wavelength

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DATA IN BRIEF 2025年 60卷 111493页

作者： Serene, Leila Batiot-Guilhe, Christelle Mazzilli, Naomi Emblanch, Christophe Univ Avignon UMR 1114 EMMAH AU INRAE F-84000 Avignon France Univ Montpellier HSM CNRS IRD Montpellier France

This dataset provides bimonthly fluorescence data from February 2020 to October 2021 at 4 springs, 1 loss and 9 unsaturated zone flows of the Fontaine de Vaucluse karst system (France). The data correspond to Excitation Emission Matrices (EEM) and emission spectra at 254 nm excitation wavelength of organic matter fluorescence. Analyses were performed with a SHIMADZU RF-5301 PC spectrofluorometer at the following wavelengths: EEM at lambda(ex) = [220;450] nm, interval = 10 nm;lambda(em) = [250;550] nm, interval = 1 nm;and 2D emission spectra at ?ex = 254nm, lambda(em) = [250;530] nm, interval = 1 nm. Milli-Q water EEMs are also provided, one for each day of analysis, to allow later correction of the Raman diffraction. Only raw data are provided to allow the user to adapt the corrections to his purpose. The originality of this dataset is the 20-months monitoring of different types of karst waters, from the saturated zone (springs with small or large catchments) to the unsaturated zone which was exceptionally accessible thanks to the Low Noise Underground Laboratory (LSBB, https://***/). This dataset was carried out to question the use of the main fluorescence indices (FI, BIX, HIX, [1] and to develop a new index to assess the qualitative groundwater transit time [2,3]. The use of this dataset could be extended to fields other than hydrogeology, such as pedology, microbiology or hydrobiology. It could be usefull to improve the understanding of the carbon cycle as carbon is the main atom constituting organic matter and fluorescence allows the characterization of the molecular structure of the molecule. (c) 2025 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://***/licenses/by/4.0/)

关键词： Humification index parafac model Unsaturated zone Carbonated aquifer Water quality

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The equivalence of Tucker3 and parafac models with two components

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CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS 2011年第1期106卷 21-26页

作者： Kroonenberg, P. M. ten Berge, J. M. F. Leiden Univ Inst Educ & Child Studies NL-2333 AK Leiden Netherlands Univ Groningen Heymans Inst Dept Psychol NL-9712 TS Groningen Netherlands

This study investigates similarities and differences between Tucker3 models with two components for each mode and parafac models with two components. If the core array of the 2 x 2 x 2 Tucker3 model is of rank 2 the solutions contain exactly the same information, but they do not when the rank of the core array is three. Two illustrative applications show the effect the different core arrays have on the solutions and their interpretability. (C) 2010 Elsevier B.V. All rights reserved.

关键词： parafac model Tucker3 model Two-component models Degeneracy Rank-two core array Rank-three core array

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Optical characterization of dissolved organic matter in the Amazon River plume and the Adjacent Ocean: Examining the relative role of mixing, photochemistry, and microbial alterations

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MARINE CHEMISTRY 2016年 186卷 178-188页

作者： Cao, Fang Medeiros, Patricia M. Miller, William L. Univ Georgia Dept Marine Sci Athens GA 30602 USA

The Amazon River is a major source of terrestrially-derived dissolved organic matter (DOM) to the Atlantic Ocean. Measurements of dissolved organic carbon (DOC) and its optical properties (absorbance and fluorescence) were made in the water within and adjacent to the Amazon River plume during two cruises conducted at periods of low (September-October/2011) and high (July/2012) river discharges. Four fluorescent components were resolved by excitation emission matrix fluoresces combined with parallel factor analysis (EEM-parafac) as two terrestrial humic-like components, one marine humic-like component, and one autochthonous protein-like component. The distribution and dynamics of optically active fraction of DOM were largely controlled by physical mixing along the Amazon River-ocean continuum, with the exception of the protein-like cornponent whose distribution was driven by factors other than dilution. Principal component analysis (PCA) enabled differentiation of water samples following gradient of terrestrial signatures and distinction of source materials associated with different fluorescent components. On board water incubation experiments with photochemical and microbial alterations revealed that photochemistry was primarily responsible for the removal of optically active fraction of DOM whereas the contribution of microbial transformation to this fraction was minor. Results from this work will provide a better understanding of DOM compositions and transformations in a globally significant river plume-ocean continuum. (C) 2016 Elsevier B.V. All rights reserved.

关键词： Amazon River plume Chromophoric dissolved organic matter (CDOM) Fluorescence Excitation emission matrix (EEM) parafac model Principal component analysis Photochemical degradation Microbial degradation

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