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Showing 1 to 11 of 11 for “"positive matrix factorization"”.

  1. Bayesian and Positive Matrix Factorization approaches to pollution source apportionment

    Lingwall, Jeff William2006

    The use of Positive Matrix Factorization (PMF) in pollution source apportionment (PSA) is examined and illustrated. A study of its settings is conducted in order to optimize them in the context of PSA. The use of a priori information in PMF is examined, in the form of target factor profiles and …

    byu Repository record

  2. Evaluating sources of volatile organic compounds in Colorado workplaces via positive matrix factorization

    Lippmann, Jadelyn, author, Carter, Ellison, advisor, Burt, Melissa, committee member, Atadero, Rebecca, committee memberColorado State University. Libraries2025

    … analyzed 61 target VOCs via EPA Method TO-15. Positive Matrix Factorization (PMF) modeling was employed to identify and apportion the sources of VOCs, providing insights into the relative contributions of indoor and outdoor pollutants. The findings inform further understanding of patterns of …

    colostate Repository record

  3. Assessment of Atlanta’s PM [subscript 2.5] source profiles using principle component analysis and positive matrix factorization

    Holm, Klaus HermanGeorgia Institute of Technology2002

    gatech Repository record

  4. Analysis of Ambient VOCs Levels and Potential Sources in Windsor

    Wang, XiaolinUniversity of Windsor2014

    Chemical Mass Balance (CMB), Positive Matrix Factorization (PMF), and Principal Component Analysis (PCA) were applied to investigate the major sources of Windsor ambient Volatile Organic Compounds (VOCs). The annual average total VOC concentrations declined from 2005 to 2006. Summer concentrations …

    windsor Repository record

  5. Simulating the atmospheric primary and secondary organic aerosols

    Τσιμπίδη, Αλεξάνδρα2009

    … Mass Spectrometry (AMS) observations and their Positive Matrix Factorization (PMF) analysis. The final goal of this work is to provide information to the policy makers regarding the response of fine PM to emission controls. PMCAMx is used to investigate changes in PM2.5 concentrations in …

    patras-thes Repository record

  6. A Diverse and Comprehensive Air Quality Modeling Analysis of Houston, Texas: How Will Changing Emissions, Industries, and Legislation Impact the Air and Human Health?

    Nelson, Delaney LynnUniversity of Houston2025

    … using a novel two-step approach that combines Positive Matrix Factorization (PMF) with Random Forest machine learning interpreted by SHapley Additive exPlanation (SHAP). VOC and NOx data from the urban Milby Park and industrial Lynchburg Ferry sites were analyzed for the O3 seasons of …

    houston Repository record

  7. Ozone Precursor Sources and Box Modeling of Ozone in Mexico City Under Altered Emission Conditions

    Akther, Tanzina 1993-University of Houston2025

    … emissions. In the second task, a modified positive matrix factorization (PMF) with Fpeak rotation (0.3 for MC-PMF and 0.5 for IC-PMF) was utilized to identify VOC emission sources. Similar eight main sources were found, albeit with differing contributions from MC-PMF and IC-PMF. While …

    houston Repository record

  8. Intraurban Spatiotemporal Variability of Ambient Air Pollutants across Metropolitan St. Louis

    Du, Li2015

    … including metrics recently added to the US EPA Positive Matrix Factorization (EPA PMF) modeling software and the sensitivity of modeling results to perturbations on the measurement uncertainties.</p>

    wustl Repository record

  9. SET-UP OF INNOVATIVE EXPERIMENTAL METODOLOGIES FOR THE ATMOSPHERIC AEROSOL CHARACTERISATION AND SOURCE APPORTIONMENT

    V. BernardoniUniversità degli Studi di Milano2010

    … (see next paragraph); 2)application of the PMF (Positive Matrix Factorization) receptor model to a 4-hour resolved dataset already available. In this work, PMF resolved seven main sources affecting the Milan urban area (re-suspended dust, construction work, secondary compounds, combustion, …

    milano Repository record

  10. Air Quality in Mexico City: Spatial and Temporal Variations of Particulate Polycyclic Aromatic Hydrocarbons and Source Apportionment of Gasoline-Versus-Diesel Vehicle Emissions

    Thornhill, Dwight Anthony CoreyVirginia Tech2007

    … types of engine emissions within the MCMA using positive matrix factorization (PMF) receptor modeling. The Aerodyne Mobile Laboratory drove throughout the MCMA in March 2006 and measured on-road concentrations of a large suite of gaseous and particulate pollutants, including carbon dioxide, …

    vt Repository record

  11. A Statistical Methods-Based Novel Approach for Fully Automated Analysis of Chromatographic Data

    Kim, SungwooVirginia Tech2024

    Atmospheric samples are complex mixtures that contain thousands of volatile organic compounds (VOCs) with diverse physicochemical properties and multiple isomers. These compounds can interact with nitrogen oxides, leading to the formation of ozone and particulate matter, which have detrimental …

    vt Repository record