Dr. Michael S. Twardowski Profile

Dr. Michael S. Twardowski

Professor at Harbor Branch Oceanographic Institute

SPIE Involvement:

Author

Publications (21)

Proceedings Article | 12 June 2023 Presentation + Paper

Calibration and preliminary performance of an in-water, integrated total scattering and backscattering sensor

Matteo Ottaviani, Michael Twardowski, Ed Fry, Michael Dewey, Cristina Orrico, Nicole Stockley

Proceedings Volume 12543, 125430E (2023) https://doi.org/10.1117/12.2663954

KEYWORDS: Calibration, Sensors, Backscatter, Scattering, Particles, Light scattering, Optical spheres, Laser scattering, Absorption, Equipment

Read Abstract +

Proceedings Article | 12 June 2023 Presentation + Paper

Preliminary results of new calibration approach and uncertainty assessment for PSICAM

Christopher Strait, Alberto Tonizzo, Rüdiger Röttgers, Wayne Slade, Michael Twardowski

Proceedings Volume 12543, 125430F (2023) https://doi.org/10.1117/12.2663974

KEYWORDS: Absorption, Calibration, Optical spheres, Spectroscopy, Light sources, Light absorption

Read Abstract +

Proceedings Article | 12 June 2023 Presentation + Paper

Insights into flow-stimulated bioluminescence flash kinetics of larvae of the ctenophore Mnemiopsis leidyi

Abigail Blackburn, Francis Letendre, Edwin Malkiel, Malcolm McFarland, Carina Poulin, Michael Latz, Michael Twardowski

Proceedings Volume 12543, 125430A (2023) https://doi.org/10.1117/12.2663937

KEYWORDS: Bioluminescence, Integrating spheres, Photomultipliers, Calibration, Organisms, Sampling rates, Radiometric calibration, Cameras

Read Abstract +

Proceedings Article | 12 June 2023 Presentation + Paper

Decomposition of the total non-water absorption coefficient for retrieval of absorption subcomponents

Srinivas Kolluru, Shirishkumar Gedam, Michael Twardowski

Proceedings Volume 12543, 125430D (2023) https://doi.org/10.1117/12.2663892

KEYWORDS: Absorption, Ocean optics, Algorithm development, Optical properties, Data modeling, Absorption spectrum, Spectral models, Light absorption, Error analysis

Read Abstract +

The total non-water absorption coefficient of seawater, 𝑎_𝑝𝑔(𝜆) (𝑚⁻¹) (light absorption coefficient after subtraction of pure water contribution) provides information about the amount of light absorbed by various optically significant substances in natural waters (𝜆 is wavelength). Partitioning 𝑎_𝑝𝑔^(𝜆) into phytoplankton, 𝑎_𝑝ℎ^(𝜆)and colored detrital matter, 𝑎_𝑑𝑔(𝜆) is useful to understand the light interaction with the distribution and variability of constituent matter, light availability at various depths, and ecological and biogeochemical cycles, as these constituents represent pools of carbon and other elements. Some of the existing partitioning methods either require ancillary inputs or assume limited shapes for constituents absorption in deriving the 𝑎_𝑝ℎ(𝜆) and 𝑎_𝑑𝑔(𝜆) from 𝑎_𝑝𝑔(𝜆). In this study, we propose a decomposition method of 𝑎_𝑝𝑔(𝜆) using a spectral optimization routine utilizing a spectral library consisting of various shapes for both phytoplankton and colored detrital matter absorption components. The proposed method does not require any ancillary inputs in deriving absorption of the constituent subcomponents. Performance of the proposed method is evaluated using two dataset compilations covering a very wide range of water types with sampling locations. Among various parameterizations tested in the decomposition method, the parameterization with the phytoplankton shape model of Ciotti et al. (2005) combined with exponential, stretched exponential, and hyperbolic shapes for colored detrital matter resulted in lower Mean Absolute Percentage Errors (MAPE) consistently across all sites. The good performance of the proposed method is characterized by average MAPE values of 17% and 13% and average percentage absolute errors (%AE) of 15.5% and 11.5% for the derived 𝑎_𝑝ℎ(443) and 𝑎_𝑑𝑔(443) respectively. The proposed method exhibited better performance with 7 - 10% lower average spectral MAPE (MAPE averaged over all wavelengths) values compared to two other existing partitioning algorithms in optically complex waters. The proposed method can be used for deriving the constituents absorption from input data of 𝑎_𝑝𝑔(𝜆) collected from various oceanographic and remote-sensing platforms. Since apg is a core product of several semi-analytical ocean color inversion algorithms, this approach has relevance to the future hyperspectral NASA PACE ocean color imager, as it is directly adaptable to hyperspectral reflectance data.

Proceedings Article | 30 May 2022 Presentation + Paper

Frugal hyperspectral imaging via low rank tensor reconstruction

Oscar Lopez, Bing Ouyang, Tom Lawrence, Alexa Ernce, Sue Gong, Nathan Gilly, Ed Malkiel, Michael Twardowski

Proceedings Volume 12118, 121180H (2022) https://doi.org/10.1117/12.2623925

KEYWORDS: Signal to noise ratio, Image segmentation, Smoothing, Hyperspectral imaging, Computer programming, Reconstruction algorithms, Compressed sensing, Modulation, Image compression, RGB color model

Read Abstract +

Proceedings Article | 4 March 2019 Presentation + Paper

Prototyping a compressive line sensing hyperspectral imaging sensor

Bing Ouyang, Michael Twardowski, Frank Caimia, Fraser Dalgleish, Cuiling Gong, Yanjun Li

Proceedings Volume 10932, 109320U (2019) https://doi.org/10.1117/12.2511981

KEYWORDS: Compressive imaging, Sensors, Digital micromirror devices, Imaging systems, CCD image sensors, Hyperspectral imaging, Image sensors, Space operations, Detector arrays, Image compression

Read Abstract +

Proceedings Article | 25 May 2018 Presentation + Paper

On plankton distributions and biophysical interactions in diverse coastal and limnological environments

Aditya Nayak, Malcolm McFarland, Michael Twardowski, James Sullivan

Proceedings Volume 10631, 106310P (2018) https://doi.org/10.1117/12.2309798

KEYWORDS: Particles, Holograms, Holography, Ocean optics, Turbulence, Imaging systems, Digital holography

Read Abstract +

Proceedings Article | 25 May 2018 Presentation + Paper

Analytical model to derive suspended particulate matter concentration in natural waters by inversion of optical attenuation and backscattering

Michael Twardowski, Cedric Jamet, Hubert Loisel

Proceedings Volume 10631, 106310H (2018) https://doi.org/10.1117/12.2309995

KEYWORDS: Particles, Scanning probe microscopy, Data modeling, Signal attenuation, Refractive index, Optical properties, Backscatter, Scattering, Water, Ocean optics

Read Abstract +

Proceedings Article | 25 May 2018 Paper

Propagation of bioluminescent signals to near-surface from mesopelagic waters

Alberto Tonizzo, Brandon Russell, James Sullivan, Michael Twardowski

Proceedings Volume 10631, 1063113 (2018) https://doi.org/10.1117/12.2310006

KEYWORDS: Absorption, Organisms, Signal to noise ratio, Water, Signal detection, Signal attenuation, Sensors, Radiative transfer, Ocean optics

Read Abstract +

Proceedings Article | 25 May 2018 Presentation + Paper

Development and assessment of lidar modeling to retrieve IOPs

Christopher Strait, Michael Twardowski, Fraser Dalgleish, Alberto Tonizzo, Anni Vuorenkoski

Proceedings Volume 10631, 106310U (2018) https://doi.org/10.1117/12.2309998

KEYWORDS: LIDAR, Signal attenuation, Multiple scattering, Particles, Scattering, Monte Carlo methods, Light scattering

Read Abstract +

Proceedings Article | 24 May 2018 Paper

Investigation of a compressive line sensing hyperspectral imaging sensor

Bing Ouyang, Michael Twardowski, Yanjun Li, Fraser Dalgleish

Proceedings Volume 10677, 106773Q (2018) https://doi.org/10.1117/12.2309937

KEYWORDS: Sensors, Digital micromirror devices, Imaging systems, Principal component analysis, Hyperspectral imaging, Signal to noise ratio, Image compression, Image sensors, Space operations, Detector arrays, Compressive imaging

Read Abstract +

Proceedings Article | 7 June 2017 Presentation

In situ particle characterization and evidence of ubiquitous particle orientation in the ocean using a submersible holographic imaging system (Conference Presentation)

Aditya Nayak, Malcolm McFarland, Nicole Stockley, Michael Twardowski, James Sullivan

Proceedings Volume 10186, 101860C (2017) https://doi.org/10.1117/12.2262880

KEYWORDS: Particles, Holography, Imaging systems, Digital holography, Databases, Holograms, Acoustics, Doppler effect, Turbulence, Ocean optics

Read Abstract +

Proceedings Article | 28 May 2015 Paper

Semi-empirical inversion technique for retrieval of quantitative attenuation profiles with underwater scanning lidar systems

Anni Vuorenkoski, Fraser Dalgleish, Michael Twardowski, Bing Ouyang, Charles Trees

Proceedings Volume 9459, 94590E (2015) https://doi.org/10.1117/12.2180158

KEYWORDS: LIDAR, Signal attenuation, Sensors, Scattering, Backscatter, Model-based design, Underwater imaging, Calibration, Multiple scattering, Ocean optics

Read Abstract +

Proceedings Article | 12 June 2012 Paper

Application of in-situ digital holography in the study of particles, organisms and bubbles within their natural environment

Siddharth Talapatra, James Sullivan, Joseph Katz, Michael Twardowski, Helen Czerski, Percy Donaghay, Jiarong Hong, Jan Rines, Malcolm McFarland, Aditya Nayak, Cao Zhang

Proceedings Volume 8372, 837205 (2012) https://doi.org/10.1117/12.920570

KEYWORDS: Particles, Holograms, Holography, Acoustics, Digital holography, Resonators, Data acquisition, Organisms, Ocean optics, Water

Read Abstract +

Proceedings Article | 12 June 2012 Paper

Biological thin layers: history, ecological significance and consequences to oceanographic sensing systems

James Sullivan, Michael Twardowski, Percy Donaghay, Jan Rines, Malcolm McFarland, Siddharth Talapatra, Joseph Katz, James Churnside, Alan Weidemann

Proceedings Volume 8372, 83720U (2012) https://doi.org/10.1117/12.921156

KEYWORDS: Acoustics, Organisms, Ocean optics, Scattering, Sensing systems, Particles, Defense and security, Backscatter, Neodymium, Imaging systems

Read Abstract +

Proceedings Article | 28 May 2010 Paper

A method for determining oceanic particle size distributions and particle composition using scanning electron microscopy coupled with energy dispersive spectroscopy

Heather Groundwater, Michael Twardowski, Heidi Dierssen, Antoine Sciandre, Scott Freeman

Proceedings Volume 7729, 77290E (2010) https://doi.org/10.1117/12.853455

KEYWORDS: Particles, Scanning electron microscopy, Chemical analysis, Image analysis, Image processing, Image filtering, Magnesium, Binary data, Spectroscopy, Ocean optics

Read Abstract +

Proceedings Article | 20 April 2010 Paper

Estimation of the polarized water leaving radiance from above water measurements

A. Tonizzo, A. Ibrahim, J. Zhou, A. Gilerson, M. Twardowski, B. Gross, F. Moshary, S. Ahmed

Proceedings Volume 7678, 767803 (2010) https://doi.org/10.1117/12.850930

KEYWORDS: Water, Sensors, Absorption, Polarization, Signal attenuation, Scattering, Ocean optics, Optical properties, Particles, Reflectivity

Read Abstract +

Proceedings Article | 29 April 2009 Paper

Polarization characteristics of coastal waters and their impact on in-water visibility

Jing Zhou, Alberto Tonizzo, Alex Gilerson, Michael Twardowski, Deric Gray, Alan Weidemann, Robert Arnone, Barry Gross, Fred Moshary, Sam Ahmed

Proceedings Volume 7317, 73170H (2009) https://doi.org/10.1117/12.820738

KEYWORDS: Polarization, Scattering, Light scattering, Monte Carlo methods, Visibility, Ocean optics, Submerged target modeling, Cameras, Polarizers, Point spread functions

Read Abstract +

Proceedings Article | 25 October 2007 Paper

Laser line scan performance prediction

Kevin Mahoney, Oscar Schofield, John Kerfoot, Tom Giddings, Joe Shirron, Mike Twardowski

Proceedings Volume 6675, 66750N (2007) https://doi.org/10.1117/12.734617

KEYWORDS: Signal attenuation, Ocean optics, Backscatter, Sensors, Data modeling, Performance modeling, Mining, Environmental sensing, Sensor performance, Optical testing

Read Abstract +

Proceedings Article | 19 May 2005 Paper

Monitoring water transparency and diver visibility in ports and harbors using aircraft hyperspectral remote sensing

Charles Trees, Paul Bissett, Heidi Dierssen, David Kohler, Mark Moline, James Mueller, Richard Pieper, Michael Twardowski, J. Ronald Zaneveld

Proceedings Volume 5780, (2005) https://doi.org/10.1117/12.607554

KEYWORDS: Visibility, Ocean optics, Remote sensing, Sensors, Transparency, Water, Signal attenuation, CCD image sensors, Hyperspectral imaging, Defense and security

Read Abstract +