SmartDATA Lab Publications
2025

Yi Wang, Zipeng Xu, Vivekanand Muralikrishnan, Joel B Harley, Michael R Tonks, Gregory S Rohrer, Amanda R Krause
4D Observations of the initiation of abnormal grain growth in commercially pure Ni Journal Article
In: Scripta materialia, vol. 264, no. 116715, pp. 116715, 2025.
@article{Wang2025-qz,
title = {4D Observations of the initiation of abnormal grain growth in
commercially pure Ni},
author = {Yi Wang and Zipeng Xu and Vivekanand Muralikrishnan and Joel B Harley and Michael R Tonks and Gregory S Rohrer and Amanda R Krause},
url = {https://www.sciencedirect.com/science/article/pii/S1359646225001782},
doi = {10.1016/j.scriptamat.2025.116715},
year = {2025},
date = {2025-07-01},
urldate = {2025-07-01},
journal = {Scripta materialia},
volume = {264},
number = {116715},
pages = {116715},
publisher = {Elsevier BV},
keywords = {},
pubstate = {published},
tppubtype = {article}
}

Kang Yang, Zekun Yang, Hanbo Yang, Junkai Zhou, Zhongzheng Ren Zhang, Linyuan Wang, Zhihui Tian, Sungwon Kim, J Harley
Dataset on guided waves from long-term structural health monitoring under uncontrolled and dynamic conditions Miscellaneous
2025.
@misc{Yang2025-oq,
title = {Dataset on guided waves from long-term structural health
monitoring under uncontrolled and dynamic conditions},
author = {Kang Yang and Zekun Yang and Hanbo Yang and Junkai Zhou and Zhongzheng Ren Zhang and Linyuan Wang and Zhihui Tian and Sungwon Kim and J Harley},
url = {http://dx.doi.org/10.1038/s41597-025-05300-5},
doi = {10.1038/s41597-025-05300-5},
year = {2025},
date = {2025-06-01},
urldate = {2025-06-01},
publisher = {Nature Publishing Group},
abstract = {Few studies address guided wave structural health monitoring
under controlled and dynamic environments, largely due to the
lack of a public benchmark dataset. To address this gap, this
paper presents a public dataset from a long-term outdoor
structural monitoring experiment conducted at the University of
Utah, Salt Lake City. The monitoring, spanning over 4.5 years,
collected approximately 6.4 million guided waves under both
regular environmental variations (e.g., daily temperature changes
ranging from 260.95 K (−12.2 °C) to 325.65 K (52.5 °C)) and
irregular variations (e.g., rain and snow). The measured guided
waves in the public dataset are also affected by sensor drift and
installation shifts consistently over time. Additionally,
thirteen types of damage were introduced to the monitored
structure to support damage detection and severity evaluation
under these conditions. The dataset includes measurement times,
temperature, humidity, air pressure, brightness, and weather
information to aid in damage detection. The provided public
dataset aims to assist researchers in developing more practical
methods for structural health monitoring in uncontrolled and
dynamic environments.},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}
under controlled and dynamic environments, largely due to the
lack of a public benchmark dataset. To address this gap, this
paper presents a public dataset from a long-term outdoor
structural monitoring experiment conducted at the University of
Utah, Salt Lake City. The monitoring, spanning over 4.5 years,
collected approximately 6.4 million guided waves under both
regular environmental variations (e.g., daily temperature changes
ranging from 260.95 K (−12.2 °C) to 325.65 K (52.5 °C)) and
irregular variations (e.g., rain and snow). The measured guided
waves in the public dataset are also affected by sensor drift and
installation shifts consistently over time. Additionally,
thirteen types of damage were introduced to the monitored
structure to support damage detection and severity evaluation
under these conditions. The dataset includes measurement times,
temperature, humidity, air pressure, brightness, and weather
information to aid in damage detection. The provided public
dataset aims to assist researchers in developing more practical
methods for structural health monitoring in uncontrolled and
dynamic environments.

Kang Yang, Tianqi Liu, Zekun Yang, Yang Zhou, Zhihui Tian, Nam H Kim, Joel B Harley
Baseline optimized autoencoder-based unsupervised anomaly detection in uncontrolled dynamic structural health monitoring Journal Article
In: Structural health monitoring, pp. 14759217251324107, 2025.
@article{Yang2025-jp,
title = {Baseline optimized autoencoder-based unsupervised anomaly
detection in uncontrolled dynamic structural health monitoring},
author = {Kang Yang and Tianqi Liu and Zekun Yang and Yang Zhou and Zhihui Tian and Nam H Kim and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:qwy9JoKyICEC},
doi = {10.1177/14759217251324107},
year = {2025},
date = {2025-03-01},
urldate = {2025-03-01},
journal = {Structural health monitoring},
pages = {14759217251324107},
publisher = {SAGE Publications},
abstract = {Autoencoder reconstruction-based unsupervised anomaly detection
is widely used in structural health monitoring. However, these
methods typically require training on historical data from
healthy structures, collected under environmental conditions
similar to the test data. This limits their practical use, as it
demands a comprehensive dataset of historical guided waves
gathered across various environmental and operational conditions.
Additionally, these methods fail when the training data contain a
significant portion of damage-induced guided waves, as the
autoencoder may reconstruct damaged waves just as effectively as
normal ones. To overcome these challenges, our anomaly detection
model is trained directly on current measurements, eliminating
the risk of environmental discrepancies between training and test
data. Furthermore, our baseline optimization strategy biases the
autoencoder toward reconstructing normal guided waves, enabling
reliable anomaly detection even when a large proportion of the
training data are damage-induced waves. Additionally, we present
a strategy to enhance the model’s practical performance by
optimizing the weight factor for baseline loss and the baseline
set size, based on guided wave reconstruction performance,
without relying on damage labels. The effectiveness of this
baseline-optimized autoencoder model, even when the training data
contain significant damage-induced guided waves, is validated
through measurements from 10 regions, each spanning 80 days of
guided wave data collected under uncontrolled and dynamic
environmental conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
is widely used in structural health monitoring. However, these
methods typically require training on historical data from
healthy structures, collected under environmental conditions
similar to the test data. This limits their practical use, as it
demands a comprehensive dataset of historical guided waves
gathered across various environmental and operational conditions.
Additionally, these methods fail when the training data contain a
significant portion of damage-induced guided waves, as the
autoencoder may reconstruct damaged waves just as effectively as
normal ones. To overcome these challenges, our anomaly detection
model is trained directly on current measurements, eliminating
the risk of environmental discrepancies between training and test
data. Furthermore, our baseline optimization strategy biases the
autoencoder toward reconstructing normal guided waves, enabling
reliable anomaly detection even when a large proportion of the
training data are damage-induced waves. Additionally, we present
a strategy to enhance the model’s practical performance by
optimizing the weight factor for baseline loss and the baseline
set size, based on guided wave reconstruction performance,
without relying on damage labels. The effectiveness of this
baseline-optimized autoencoder model, even when the training data
contain significant damage-induced guided waves, is validated
through measurements from 10 regions, each spanning 80 days of
guided wave data collected under uncontrolled and dynamic
environmental conditions.

Lee Shi Yn, Zairil Zaludin, Joel B Harley, Jung-Ryul Lee, Mohammad Yazdi Harmin, Chia Chen Ciang
Statistical Thresholding of Ultrasonic Amplitude Maps for Automated Damage Segmentation Journal Article
In: Journal of Aeronautics, Astronautics and Aviation, vol. 57, no. 3S, pp. 319–327, 2025.
@article{Yn2025-bx,
title = {Statistical Thresholding of Ultrasonic Amplitude Maps for
Automated Damage Segmentation},
author = {Lee Shi Yn and Zairil Zaludin and Joel B Harley and Jung-Ryul Lee and Mohammad Yazdi Harmin and Chia Chen Ciang},
url = {https://www.airitilibrary.com/Article/Detail/P20140627004-N202504100011-00005},
doi = {10.6125/JoAAA.202503_57(3S).04},
year = {2025},
date = {2025-03-01},
urldate = {2025-03-01},
journal = {Journal of Aeronautics, Astronautics and Aviation},
volume = {57},
number = {3S},
pages = {319–327},
publisher = {Aeronautical and Astronautical Society of the Republic of China},
abstract = {Amplitude maps generated by ultrasound imaging are frequently
utilized to visualize invisible damages in thin-walled
aero-mechanical structures. Accurate evaluation of damage size
from these maps is crucial; however, a reliable automated method
for this purpose under the influence of imaging noise is not
available. To address this issue, four threshold calculation
methods based on statistical analysis of noise content in an
amplitude map were developed. These candidates were numerically
optimized using amplitude maps containing damages of various
sizes and Gaussian noise of differing intensities. The candidate
demonstrating the greatest immunity to parameter variations and
the highest potential for accurate damage size evaluation was
identified. This candidate was then parametrically optimized and
benchmarked against k-means clustering. The results demonstrate
that the newly proposed statistical …},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
utilized to visualize invisible damages in thin-walled
aero-mechanical structures. Accurate evaluation of damage size
from these maps is crucial; however, a reliable automated method
for this purpose under the influence of imaging noise is not
available. To address this issue, four threshold calculation
methods based on statistical analysis of noise content in an
amplitude map were developed. These candidates were numerically
optimized using amplitude maps containing damages of various
sizes and Gaussian noise of differing intensities. The candidate
demonstrating the greatest immunity to parameter variations and
the highest potential for accurate damage size evaluation was
identified. This candidate was then parametrically optimized and
benchmarked against k-means clustering. The results demonstrate
that the newly proposed statistical …

Maximillian T Diaz, Lavanya Durai, Kalyn M Kearney, Erica M Lindbeck, Isaly Tappan, Joel B Harley, Jennifer A Nichols
Evaluating recruitment methods for selection bias: A large, experimental study of hand biomechanics Journal Article
In: Journal of biomechanics, vol. 182, no. 112558, pp. 112558, 2025.
@article{Diaz2025-cm,
title = {Evaluating recruitment methods for selection bias: A large,
experimental study of hand biomechanics},
author = {Maximillian T Diaz and Lavanya Durai and Kalyn M Kearney and Erica M Lindbeck and Isaly Tappan and Joel B Harley and Jennifer A Nichols},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:CYCckWUYoCcC},
doi = {10.1016/j.jbiomech.2025.112558},
year = {2025},
date = {2025-03-01},
urldate = {2025-03-01},
journal = {Journal of biomechanics},
volume = {182},
number = {112558},
pages = {112558},
publisher = {Elsevier BV},
abstract = {Biomechanics studies rely on non-random recruitment methods to
obtain study participants. However, the use of common recruitment
methods and small sample sizes may influence a given study's
generalizability due to selection bias. To improve
generalizability, ecological validity, and participant
convenience, recent biomechanics studies have moved beyond lab
conditions. However, it is unknown if simply leaving the lab
space and increasing sample sizes reduces the risks associated
with selection bias. Previous studies relied on chart and
literature reviews to identify selection bias. Herein, we build
upon this work by exploring the potential for and influence of
selection bias in three common recruiting methods by performing
an experimental, population-level study on hand biomechanics.
Hand biomechanics was assessed in the community using a portable
lab setup to measure hand function, grip strength, and pinch
strength. A total of 642 apparently healthy participants were
recruited across 18 locations, with 426 participants selected
based on complete data responses and being between the ages of 18
to 35. Sex stratified analysis was performed to see how
recruiting only biomechanists, undergraduate students, or
university affiliates changed population estimates of hand
strength. The presence of selection bias was observed in all
three test cases with both male and female biomechanists,
graduate students, and non-university affiliates having
significant increases in pinch and grip strengths ranging from
6.2% to 19.4% above overall population values. This study
quantitively shows how simply leaving the lab and increasing
subject recruitment does not eliminate the potential for
selection bias in studies of hand biomechanics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
obtain study participants. However, the use of common recruitment
methods and small sample sizes may influence a given study's
generalizability due to selection bias. To improve
generalizability, ecological validity, and participant
convenience, recent biomechanics studies have moved beyond lab
conditions. However, it is unknown if simply leaving the lab
space and increasing sample sizes reduces the risks associated
with selection bias. Previous studies relied on chart and
literature reviews to identify selection bias. Herein, we build
upon this work by exploring the potential for and influence of
selection bias in three common recruiting methods by performing
an experimental, population-level study on hand biomechanics.
Hand biomechanics was assessed in the community using a portable
lab setup to measure hand function, grip strength, and pinch
strength. A total of 642 apparently healthy participants were
recruited across 18 locations, with 426 participants selected
based on complete data responses and being between the ages of 18
to 35. Sex stratified analysis was performed to see how
recruiting only biomechanists, undergraduate students, or
university affiliates changed population estimates of hand
strength. The presence of selection bias was observed in all
three test cases with both male and female biomechanists,
graduate students, and non-university affiliates having
significant increases in pinch and grip strengths ranging from
6.2% to 19.4% above overall population values. This study
quantitively shows how simply leaving the lab and increasing
subject recruitment does not eliminate the potential for
selection bias in studies of hand biomechanics.

Kang Yang, Kang Gao, Junkai Zhou, Chao Gao, Tingsong Xiao, Harsha Vardhan Tetali, Joel B Harley
In: Ultrasonics, no. 107632, pp. 107632, 2025.
@article{Yang2025-aj,
title = {Optimal principal component and measurement interval selection
for PCA reconstruction-based anomaly detection in uncontrolled
structural health monitoring},
author = {Kang Yang and Kang Gao and Junkai Zhou and Chao Gao and Tingsong Xiao and Harsha Vardhan Tetali and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:hSRAE-fF4OAC},
doi = {10.1016/j.ultras.2025.107632},
year = {2025},
date = {2025-03-01},
urldate = {2025-03-01},
journal = {Ultrasonics},
number = {107632},
pages = {107632},
publisher = {Elsevier BV},
abstract = {PCA reconstruction-based techniques are widely used in guided
wave structural health monitoring to facilitate unsupervised
damage detection. The measurement interval of collecting
evaluation data significantly influences the correlation among
the data points, impacting principal component values and,
consequently, the accuracy of damage detection. Despite its
importance, there has been limited research on the selection of
suitable components and measurement intervals to reduce false
alarms. This paper seeks to develop strategies for identifying
the optimal number of principal components and measurement
intervals for PCA reconstruction-based damage detection methods.
Our results indicate that the patterns of change in
reconstruction coefficients, based on the number of components
used in PCA reconstruction and the measurement interval for
collecting evaluation data, are effective indicators for
determining the optimal principal components and measurement
intervals for damage detection, without using any damage
information. The effectiveness of the indicators for determining
optimal components and measurement intervals is validated using
evaluation sets collected under uncontrolled and dynamic
monitoring conditions, with measurement intervals ranging from 86
to 8600 s per measurement.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
wave structural health monitoring to facilitate unsupervised
damage detection. The measurement interval of collecting
evaluation data significantly influences the correlation among
the data points, impacting principal component values and,
consequently, the accuracy of damage detection. Despite its
importance, there has been limited research on the selection of
suitable components and measurement intervals to reduce false
alarms. This paper seeks to develop strategies for identifying
the optimal number of principal components and measurement
intervals for PCA reconstruction-based damage detection methods.
Our results indicate that the patterns of change in
reconstruction coefficients, based on the number of components
used in PCA reconstruction and the measurement interval for
collecting evaluation data, are effective indicators for
determining the optimal principal components and measurement
intervals for damage detection, without using any damage
information. The effectiveness of the indicators for determining
optimal components and measurement intervals is validated using
evaluation sets collected under uncontrolled and dynamic
monitoring conditions, with measurement intervals ranging from 86
to 8600 s per measurement.

Kang Yang, Chao Zhang, Hanbo Yang, Linyuan Wang, Nam H Kim, Joel B Harley
Improving unsupervised long-term damage detection in an uncontrolled environment through noise-augmentation strategy Journal Article
In: Mechanical systems and signal processing, vol. 224, no. 112076, pp. 112076, 2025.
@article{Yang2025-ur,
title = {Improving unsupervised long-term damage detection in an
uncontrolled environment through noise-augmentation strategy},
author = {Kang Yang and Chao Zhang and Hanbo Yang and Linyuan Wang and Nam H Kim and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:TlpoogIpr_IC},
doi = {10.1016/j.ymssp.2024.112076},
year = {2025},
date = {2025-02-01},
urldate = {2025-02-01},
journal = {Mechanical systems and signal processing},
volume = {224},
number = {112076},
pages = {112076},
publisher = {Elsevier BV},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Ziqin Ding, Si Chen, Hanbo Yang, Kang Yang, Vladimir A Rakov, Joel B Harley, Yanan Zhu
Identification of lightning strikes to towers using machine-learning approach Miscellaneous
105th Annual Meeting of the American Meteorological Society, 2025.
@misc{Ding2025-zl,
title = {Identification of lightning strikes to towers using
machine-learning approach},
author = {Ziqin Ding and Si Chen and Hanbo Yang and Kang Yang and Vladimir A Rakov and Joel B Harley and Yanan Zhu},
url = {https://ams.confex.com/ams/105ANNUAL/meetingapp.cgi/Paper/447159},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
publisher = {AMS},
abstract = {Lightning often strikes tall objects and, hence, poses
significant threat to infrastructure. Modern lightning
locating systems can provide crucial information about
lightning, such as strike coordinates, peak current, etc., but
cannot tell whether the stroke terminated on a tall object
such as tower. Lightning electromagnetic field pulses (LEMP)
have been used to infer lightning currents. Using the unique
electric field pulse signatures of the tower terminated
lightning collected at the Lightning Observatory in
Gainesville (LOG), Florida, we present a machine-learning
approach to classify lightning strikes to towers. The
classification model used in this study is based on supervised
Multi-Layer Perceptron model (MLP), aiming to capture complex
pulse patterns with the neural network architecture. We
refined the model by tuning the configuration of the training
dataset, and validated its performance with Local
Interpretable Model-agnostic Explanations. The result shows
that an overall 99.97% classification accuracy can be
achieved, with 90% and 99.97% classification accuracy for
tower terminated lightning and non-tower terminated lightning,
respectively.},
howpublished = {105th Annual Meeting of the American Meteorological Society},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}
significant threat to infrastructure. Modern lightning
locating systems can provide crucial information about
lightning, such as strike coordinates, peak current, etc., but
cannot tell whether the stroke terminated on a tall object
such as tower. Lightning electromagnetic field pulses (LEMP)
have been used to infer lightning currents. Using the unique
electric field pulse signatures of the tower terminated
lightning collected at the Lightning Observatory in
Gainesville (LOG), Florida, we present a machine-learning
approach to classify lightning strikes to towers. The
classification model used in this study is based on supervised
Multi-Layer Perceptron model (MLP), aiming to capture complex
pulse patterns with the neural network architecture. We
refined the model by tuning the configuration of the training
dataset, and validated its performance with Local
Interpretable Model-agnostic Explanations. The result shows
that an overall 99.97% classification accuracy can be
achieved, with 90% and 99.97% classification accuracy for
tower terminated lightning and non-tower terminated lightning,
respectively.
2024
Liza Garcia, Jose C B Dubeux, Igor Lima Bretas, Luana M Dantas Queiroz, Cristian T E Mendes, Chang Zao, Joel Harley, Alina Zare, Zhou Tang
Exploring Soil Carbon Sequestration Potential in Florida: A Comparative Analysis of Beef Cattle Management Practices Miscellaneous
ASA, CSSA, SSSA International Annual Meeting, 2024.
@misc{Garcia2024-hq,
title = {Exploring Soil Carbon Sequestration Potential in Florida: A
Comparative Analysis of Beef Cattle Management Practices},
author = {Liza Garcia and Jose C B Dubeux and Igor Lima Bretas and Luana M Dantas Queiroz and Cristian T E Mendes and Chang Zao and Joel Harley and Alina Zare and Zhou Tang},
url = {https://scisoc.confex.com/scisoc/2024am/meetingapp.cgi/Paper/156762},
year = {2024},
date = {2024-11-01},
booktitle = {ASA, CSSA, SSSA International Annual Meeting},
publisher = {ASA-CSSA-SSSA},
abstract = {Florida's beef cattle systems rely on grazing forages, with
grazing lands conta...},
howpublished = {ASA, CSSA, SSSA International Annual Meeting},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}
grazing lands conta...

Rishabh Gupta, Satya K Pothapragada, Weihuang Xu, Prateek Kumar Goel, Miguel A Barrera, Mira S Saldanha, Joel B Harley, Kelly T Morgan, Alina Zare, Lincoln Zotarelli
Estimating soil mineral nitrogen from data-sparse field experiments using crop model-guided deep learning approach Journal Article
In: Computers and electronics in agriculture, vol. 225, no. 109355, pp. 109355, 2024.
@article{Gupta2024-zx,
title = {Estimating soil mineral nitrogen from data-sparse field
experiments using crop model-guided deep learning approach},
author = {Rishabh Gupta and Satya K Pothapragada and Weihuang Xu and Prateek Kumar Goel and Miguel A Barrera and Mira S Saldanha and Joel B Harley and Kelly T Morgan and Alina Zare and Lincoln Zotarelli},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:QUX0mv85b1cC},
doi = {10.1016/j.compag.2024.109355},
year = {2024},
date = {2024-10-01},
urldate = {2024-09-01},
journal = {Computers and electronics in agriculture},
volume = {225},
number = {109355},
pages = {109355},
publisher = {Elsevier BV},
abstract = {Sandy soils are susceptible to excessive nitrogen (N) leaching
under intensive crop production which is linked with the soil's
low nutrient holding capacity and high-water infiltration rate.
Estimating soil mineral nitrogen (SMN) at the daily time-step is
crucial in providing fertilizer recommendations balancing plant
nitrogen use efficiency (NUE) and N losses to the environment.
Crop models [e.g., Decision Support System for Agrotechnology
Transfer (DSSAT)] can simulate the trend of SMN in varied
fertilizer rates and timing of application but are unable to
replicate its magnitude due to the inability to capture
high-water table conditions in a sub-irrigated soil. As an
alternative to such physics-based model, time-series deep
learning (DL) models based on a long short-term memory (LSTM) are
promising in understanding nonlinearity among complex variables.
Yet, purely data-driven DL models for crops are difficult to
obtain due to the insufficient amount of data available and the
excessive costs with producing more data. To address this
challenge, a hybrid model (hybrid-LSTM) was developed by
leveraging both the DSSAT andLSTM models to estimate daily SMN
primarily using daily weather, applied fertilizer rates- timings,
and the SMN sparse observations. This study used the observations
from field trials conducted between 2010-2014 in Hastings, FL.
The first step was to calibrate the DSSAT-SUBSTOR-Potato model to
produce reliable SMN of the topsoil for treatments with varied N
applied fertilizer rates split among the pre-planting, emergence,
and tuber-initiation stages of the potato crop. Thereafter, the
hybrid-LSTM model was trained on the calibrated DSSAT simulated
SMN time-series and fine-tuned its predictions using the observed
SMN to improve DSSAT simulated SMN. The hybrid-LSTM model was
then tested on both calibrated and uncalibrated DSSAT SMN
simulations where it outperformed the DSSAT model (range of
improvement ranged ~18-30% on comparing the normalized root mean
squared error) in providing reliable estimates of SMN across most
of the farms and years. This novel hybrid modeling approach could
guide stakeholders and farmers to build sustainable N management
with improved crop NUE and yield and help in minimizing
environmental losses.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
under intensive crop production which is linked with the soil's
low nutrient holding capacity and high-water infiltration rate.
Estimating soil mineral nitrogen (SMN) at the daily time-step is
crucial in providing fertilizer recommendations balancing plant
nitrogen use efficiency (NUE) and N losses to the environment.
Crop models [e.g., Decision Support System for Agrotechnology
Transfer (DSSAT)] can simulate the trend of SMN in varied
fertilizer rates and timing of application but are unable to
replicate its magnitude due to the inability to capture
high-water table conditions in a sub-irrigated soil. As an
alternative to such physics-based model, time-series deep
learning (DL) models based on a long short-term memory (LSTM) are
promising in understanding nonlinearity among complex variables.
Yet, purely data-driven DL models for crops are difficult to
obtain due to the insufficient amount of data available and the
excessive costs with producing more data. To address this
challenge, a hybrid model (hybrid-LSTM) was developed by
leveraging both the DSSAT andLSTM models to estimate daily SMN
primarily using daily weather, applied fertilizer rates- timings,
and the SMN sparse observations. This study used the observations
from field trials conducted between 2010-2014 in Hastings, FL.
The first step was to calibrate the DSSAT-SUBSTOR-Potato model to
produce reliable SMN of the topsoil for treatments with varied N
applied fertilizer rates split among the pre-planting, emergence,
and tuber-initiation stages of the potato crop. Thereafter, the
hybrid-LSTM model was trained on the calibrated DSSAT simulated
SMN time-series and fine-tuned its predictions using the observed
SMN to improve DSSAT simulated SMN. The hybrid-LSTM model was
then tested on both calibrated and uncalibrated DSSAT SMN
simulations where it outperformed the DSSAT model (range of
improvement ranged ~18-30% on comparing the normalized root mean
squared error) in providing reliable estimates of SMN across most
of the farms and years. This novel hybrid modeling approach could
guide stakeholders and farmers to build sustainable N management
with improved crop NUE and yield and help in minimizing
environmental losses.

Kalyn M Kearney, Tamara Ordonez Diaz, Joel B Harley, Jennifer A Nichols
From simulation to reality: Predicting torque with fatigue onset via transfer learning Journal Article
In: IEEE transactions on neural systems and rehabilitation engineering: a publication of the IEEE Engineering in Medicine and Biology Society, vol. 32, pp. 3669–3676, 2024.
@article{Kearney2024-ys,
title = {From simulation to reality: Predicting torque with fatigue onset
via transfer learning},
author = {Kalyn M Kearney and Tamara Ordonez Diaz and Joel B Harley and Jennifer A Nichols},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:mWEH9CqjF64C},
doi = {10.1109/TNSRE.2024.3465016},
year = {2024},
date = {2024-10-01},
urldate = {2024-10-01},
journal = {IEEE transactions on neural systems and rehabilitation
engineering: a publication of the IEEE Engineering in Medicine
and Biology Society},
volume = {32},
pages = {3669–3676},
publisher = {Institute of Electrical and Electronics Engineers (IEEE)},
abstract = {Muscle fatigue impacts upper extremity function but is often
overlooked in biomechanical models. The present work leveraged a
transfer learning approach to improve torque predictions during
fatiguing upper extremity movements. We developed two artificial
neural networks to model sustained elbow flexion: one trained
solely on recorded data (i.e., direct learning) and one
pre-trained on simulated data and fine-tuned on recorded data
(i.e., transfer learning). We simulated muscle activations and
joint torques using a musculoskeletal model and a muscle fatigue model (n = 1,701 simulations). We also recorded static
subject-specific features (e.g., anthropometric measurements) and
dynamic muscle activations and torques during sustained elbow flexion in healthy young adults (n = 25 subjects). Using the
simulated dataset, we pre-trained a long short-term memory neural
network (LSTM) to regress fatiguing elbow flexion torque from
muscle activations. We concatenated this pre-trained LSTM with a
feedforward architecture, and fine-tuned the model on recorded
muscle activations and static features to predict elbow flexion
torques. We trained a similar architecture solely on the recorded
data and compared each neural network's predictions on 5
leave-out subjects' data. The transfer learning model
outperformed the direct learning model, as indicated by a
decrease of 24.9% in their root-mean-square-errors (6.22 Nm and
8.28 Nm, respectively). The transfer learning model and direct
learning model outperformed analogous musculoskeletal
simulations, which consistently underpredicted elbow flexion
torque. Our results suggest that transfer learning from simulated
to recorded datasets can decrease reliance on assumptions
inherent to biomechanical models and yield predictions robust to
real-world conditions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
overlooked in biomechanical models. The present work leveraged a
transfer learning approach to improve torque predictions during
fatiguing upper extremity movements. We developed two artificial
neural networks to model sustained elbow flexion: one trained
solely on recorded data (i.e., direct learning) and one
pre-trained on simulated data and fine-tuned on recorded data
(i.e., transfer learning). We simulated muscle activations and
joint torques using a musculoskeletal model and a muscle fatigue model (n = 1,701 simulations). We also recorded static
subject-specific features (e.g., anthropometric measurements) and
dynamic muscle activations and torques during sustained elbow flexion in healthy young adults (n = 25 subjects). Using the
simulated dataset, we pre-trained a long short-term memory neural
network (LSTM) to regress fatiguing elbow flexion torque from
muscle activations. We concatenated this pre-trained LSTM with a
feedforward architecture, and fine-tuned the model on recorded
muscle activations and static features to predict elbow flexion
torques. We trained a similar architecture solely on the recorded
data and compared each neural network's predictions on 5
leave-out subjects' data. The transfer learning model
outperformed the direct learning model, as indicated by a
decrease of 24.9% in their root-mean-square-errors (6.22 Nm and
8.28 Nm, respectively). The transfer learning model and direct
learning model outperformed analogous musculoskeletal
simulations, which consistently underpredicted elbow flexion
torque. Our results suggest that transfer learning from simulated
to recorded datasets can decrease reliance on assumptions
inherent to biomechanical models and yield predictions robust to
real-world conditions.

Raid S Alrashidi, Rami Zamzami, Megan S Voss, Daniel J Alabi, Christopher C Ferraro, H R Hamilton, Joel B Harley, Kyle A Riding
UHPC Fresh Chloride Limit Testing Journal Article
In: Special Publication of the American Concrete Institute, vol. 363, pp. 1–20, 2024.
@article{Alrashidi2024-np,
title = {UHPC Fresh Chloride Limit Testing},
author = {Raid S Alrashidi and Rami Zamzami and Megan S Voss and Daniel J Alabi and Christopher C Ferraro and H R Hamilton and Joel B Harley and Kyle A Riding},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&user=Isf8yn0AAAAJ&cstart=100&pagesize=100&citation_for_view=Isf8yn0AAAAJ:SGW5VrABaM0C},
doi = {10.14359/51742104},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
journal = {Special Publication of the American Concrete Institute},
volume = {363},
pages = {1–20},
publisher = {American Concrete Institute},
abstract = {UHPC Fresh Chloride Limit Testing Search Subscribe to Email ▼
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read
more about membership Types of Membership Individual Student
Young Professional Organizational Sustaining ACI MEMBERSHIP Enjoy
the benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the
American Concrete Institute is a leading authority and resource
worldwide for the development, dissemination, and adoption of its
consensus-based standards, technical resources, …},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read
more about membership Types of Membership Individual Student
Young Professional Organizational Sustaining ACI MEMBERSHIP Enjoy
the benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the
American Concrete Institute is a leading authority and resource
worldwide for the development, dissemination, and adoption of its
consensus-based standards, technical resources, …

Woohyun Eum, G Austin Simon, Charlie Tran, Joel B Harley
Lamb wave anomaly detection by ensembling spatial and wavenumber domains Proceedings Article
In: Annual Review of Progress in Quantitative Nondestructive Evaluation, pp. V001T07A005, American Society of Mechanical Engineers, 2024.
@inproceedings{Eum2024-yo,
title = {Lamb wave anomaly detection by ensembling spatial and wavenumber
domains},
author = {Woohyun Eum and G Austin Simon and Charlie Tran and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:SnGPuo6Feq8C},
doi = {10.1115/qnde2024-136845},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
booktitle = {Annual Review of Progress in Quantitative Nondestructive
Evaluation},
volume = {88162},
pages = {V001T07A005},
publisher = {American Society of Mechanical Engineers},
abstract = {Abstract Guided wave field anomaly detection has proven to be a
feasible tool for nondestructive evaluation and structural health
monitoring. These anomaly detection methods are often based on
the fact that waves in damaged regions and undamaged regions
propagate differently. Yet, most anomaly detection approaches are
performed over a single domain, resulting in poor damage
discrimination under certain conditions. By analyzing wave
propagation in multiple domains, we should be able to achieve
more robust detection. We present two methods for analyzing wave
propagation in the spatial domain and wavenumber domain to detect
and locate damaged regions. To validate our approach, we generate
simulated guided wave fields and varied wave speed in two
square-shaped regions, representing damage. In the spatial
domain, we utilize pixel intensity change to detect anomalies. In
the wavenumber domain, we cluster wave modes in polar coordinates
using insights from solutions to the Helmholtz equation. By
ensembling results from our detection methods in both domains, we
can achieve more robust damage detection. We employ the
intersection over union (IOU) score to quantitatively assess this
approach. Our approach achieves an IoU score of 47% when
utilizing only the spatial domain, with improvements to 78.5%
upon model ensembling.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
feasible tool for nondestructive evaluation and structural health
monitoring. These anomaly detection methods are often based on
the fact that waves in damaged regions and undamaged regions
propagate differently. Yet, most anomaly detection approaches are
performed over a single domain, resulting in poor damage
discrimination under certain conditions. By analyzing wave
propagation in multiple domains, we should be able to achieve
more robust detection. We present two methods for analyzing wave
propagation in the spatial domain and wavenumber domain to detect
and locate damaged regions. To validate our approach, we generate
simulated guided wave fields and varied wave speed in two
square-shaped regions, representing damage. In the spatial
domain, we utilize pixel intensity change to detect anomalies. In
the wavenumber domain, we cluster wave modes in polar coordinates
using insights from solutions to the Helmholtz equation. By
ensembling results from our detection methods in both domains, we
can achieve more robust damage detection. We employ the
intersection over union (IOU) score to quantitatively assess this
approach. Our approach achieves an IoU score of 47% when
utilizing only the spatial domain, with improvements to 78.5%
upon model ensembling.
Megan S Voss, Daniel Alabi, Raid S Alrashidi, Taylor A Rawlinson, Christopher C Ferraro, H R Hamilton, Joel B Harley, Kyle A Riding
Development of Modified Double-Punch Test for Quality-Control Testing of UHPC Tensile Performance Journal Article
In: Special Publication, vol. 363, pp. 38–59, 2024.
@article{Voss2024-sc,
title = {Development of Modified Double-Punch Test for Quality-Control
Testing of UHPC Tensile Performance},
author = {Megan S Voss and Daniel Alabi and Raid S Alrashidi and Taylor A Rawlinson and Christopher C Ferraro and H R Hamilton and Joel B Harley and Kyle A Riding},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:eO3_k5sD8BwC},
year = {2024},
date = {2024-07-01},
journal = {Special Publication},
volume = {363},
pages = {38–59},
abstract = {Development of Modified Double-Punch Test for Quality-Control
Testing of UHPC Tensile Performance Search Subscribe to Email ▼
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read more
about membership Types of Membership Individual Student Young
Professional Organizational Sustaining ACI MEMBERSHIP Enjoy the
benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the American
Concrete Institute is a leading authority and resource worldwide
for the development, dissemination, …},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Testing of UHPC Tensile Performance Search Subscribe to Email ▼
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read more
about membership Types of Membership Individual Student Young
Professional Organizational Sustaining ACI MEMBERSHIP Enjoy the
benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the American
Concrete Institute is a leading authority and resource worldwide
for the development, dissemination, …

Daniel J Alabi, Megan S Voss, Raid S Alrashidi, Christopher C Ferraro, Kyle Riding, Joel B Harley
Electromagnetic Sensor for the Nondestructive Testing of Ultra-High Performance Concrete Journal Article
In: Special Publication of the American Concrete Institute, vol. 363, pp. 21–37, 2024.
@article{Alabi2024-cn,
title = {Electromagnetic Sensor for the Nondestructive Testing of Ultra-High Performance Concrete},
author = {Daniel J Alabi and Megan S Voss and Raid S Alrashidi and Christopher C Ferraro and Kyle Riding and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:DkZNVXde3BIC},
doi = {10.14359/51742105},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
journal = {Special Publication of the American Concrete Institute},
volume = {363},
pages = {21–37},
publisher = {American Concrete Institute},
abstract = {Electromagnetic Sensor for the Nondestructive Testing of
Ultra-High Performance Concrete Search Subscribe to Email ▼
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read
more about membership Types of Membership Individual Student
Young Professional Organizational Sustaining ACI MEMBERSHIP Enjoy
the benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the
American Concrete Institute is a leading authority and resource
worldwide for the development, dissemination, and adoption …},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Ultra-High Performance Concrete Search Subscribe to Email ▼
Membership Membership In today’s market, it is imperative to be
knowledgeable and have an edge over the competition. ACI members
have it…they are engaged, informed, and stay up to date by taking
advantage of benefits that ACI membership provides them. Read
more about membership Types of Membership Individual Student
Young Professional Organizational Sustaining ACI MEMBERSHIP Enjoy
the benefits of an ACI Membership Learn More Become an ACI Member
Member Directory Sustaining Members Honors and Awards Career
Center About ACI The American Concrete Institute Founded in 1904
and headquartered in Farmington Hills, Michigan, USA, the
American Concrete Institute is a leading authority and resource
worldwide for the development, dissemination, and adoption …

Erica M Lindbeck, Maximillian T Diaz, Jennifer A Nichols, Joel B Harley
Surrogate simulation of subject-specific lateral pinch via deep learning Proceedings Article
In: Proc. of the Annu. Int. Conf. IEEE Eng. Med. Biol. Soc., pp. 1–4, IEEE, 2024.
@inproceedings{Lindbeck2024-vo,
title = {Surrogate simulation of subject-specific lateral pinch via deep
learning},
author = {Erica M Lindbeck and Maximillian T Diaz and Jennifer A Nichols and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:jSAVyFp_754C},
doi = {10.1109/EMBC53108.2024.10782182},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
booktitle = {Proc. of the Annu. Int. Conf. IEEE Eng. Med. Biol. Soc.},
volume = {2024},
pages = {1–4},
publisher = {IEEE},
abstract = {Musculoskeletal modeling and simulation is often a lengthy and
computationally expensive process, particularly when developing
and using personalized models. We present a deep learning-based
adaptive surrogate model for lateral pinch, which accepts both
musculoskeletal parameters and muscle activations as input for
personalization and simulation. This model matches traditional
OpenSim forward dynamics with an average root-mean-squared error
(RMSE) of 2.27 N, within standard errors of experimental
measurements, while demonstrating sensitivity to both categories
of input and performing thousand of simulations in seconds
(10-1000x faster than traditional multi-body simulations). In
addition to direct use as a surrogate, the differentiable nature
of the model may support future use in optimization problems,
while its flexibility may support adaptation to modeling of
experimental data.},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
computationally expensive process, particularly when developing
and using personalized models. We present a deep learning-based
adaptive surrogate model for lateral pinch, which accepts both
musculoskeletal parameters and muscle activations as input for
personalization and simulation. This model matches traditional
OpenSim forward dynamics with an average root-mean-squared error
(RMSE) of 2.27 N, within standard errors of experimental
measurements, while demonstrating sensitivity to both categories
of input and performing thousand of simulations in seconds
(10-1000x faster than traditional multi-body simulations). In
addition to direct use as a surrogate, the differentiable nature
of the model may support future use in optimization problems,
while its flexibility may support adaptation to modeling of
experimental data.

Zhihui Tian, John Upchurch, G Austin Simon, José Dubeux, Alina Zare, Chang Zhao, Joel B Harley
Quantifying heterogeneous ecosystem services with multi-label soft classification Proceedings Article
In: IGARSS 2024 - 2024 IEEE International Geoscience and Remote Sensing Symposium, pp. 427–431, IEEE, 2024.
@inproceedings{Tian2024-ml,
title = {Quantifying heterogeneous ecosystem services with multi-label
soft classification},
author = {Zhihui Tian and John Upchurch and G Austin Simon and José Dubeux and Alina Zare and Chang Zhao and Joel B Harley},
url = {http://dx.doi.org/10.1109/igarss53475.2024.10642804},
doi = {10.1109/igarss53475.2024.10642804},
year = {2024},
date = {2024-07-01},
urldate = {2024-07-01},
booktitle = {IGARSS 2024 - 2024 IEEE International Geoscience and Remote
Sensing Symposium},
pages = {427–431},
publisher = {IEEE},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}

Ishan D Khurjekar, Joel B Harley
Reliability assessment of guided wave damage localization with deep learning uncertainty quantification methods Journal Article
In: NDT & E international: independent nondestructive testing and evaluation, vol. 144, no. 103099, pp. 103099, 2024.
@article{Khurjekar2024-cj,
title = {Reliability assessment of guided wave damage localization with deep learning uncertainty quantification methods},
author = {Ishan D Khurjekar and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&user=Isf8yn0AAAAJ&sortby=pubdate&citation_for_view=Isf8yn0AAAAJ:kzcSZmkxUKAC},
doi = {10.1016/j.ndteint.2024.103099},
year = {2024},
date = {2024-06-01},
urldate = {2024-06-01},
journal = {NDT & E international: independent nondestructive testing and evaluation},
volume = {144},
number = {103099},
pages = {103099},
publisher = {Elsevier BV},
abstract = {Guided wave-based structural health monitoring is an attractive
option for detecting structural defects in an automated manner.
In this work, we focus on the task of damage localization. Deep
learning methods have been shown to have superior performance for
damage localization. Yet, environmental variations introduce
uncertainty in the system and reduce its reliability. For this
reason, it is crucial to assess the reliability of estimates
taken from structural health monitoring systems. In this work, we
estimate the localization reliability from a single snapshot of
sparse array guided wave measurements instead of reporting values
averaged over an entire set of test measurements. The assessment
strategy can be added to any deep learning localization model and
produces both a localization and uncertainty estimate. The deep
learning model is trained using only guided wave simulations. We
assess the uncertainty using both simulated and experimental data
with temperature variations. Multiple deep learning-based
uncertainty quantification methods are analyzed. Results
demonstrate correlations between uncertainty, temperature
variations, and the presence of synthetic damage. We also compare
with reliability derived from delay-and-sum localization. We find
that a deep ensemble learning strategy provides the most reliable
damage localization and uncertainty quantification.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
option for detecting structural defects in an automated manner.
In this work, we focus on the task of damage localization. Deep
learning methods have been shown to have superior performance for
damage localization. Yet, environmental variations introduce
uncertainty in the system and reduce its reliability. For this
reason, it is crucial to assess the reliability of estimates
taken from structural health monitoring systems. In this work, we
estimate the localization reliability from a single snapshot of
sparse array guided wave measurements instead of reporting values
averaged over an entire set of test measurements. The assessment
strategy can be added to any deep learning localization model and
produces both a localization and uncertainty estimate. The deep
learning model is trained using only guided wave simulations. We
assess the uncertainty using both simulated and experimental data
with temperature variations. Multiple deep learning-based
uncertainty quantification methods are analyzed. Results
demonstrate correlations between uncertainty, temperature
variations, and the presence of synthetic damage. We also compare
with reliability derived from delay-and-sum localization. We find
that a deep ensemble learning strategy provides the most reliable
damage localization and uncertainty quantification.

Amanda Krause, Michael Tonks, Joel Harley
Elucidating Abnormal Grain Growth in Thermomagnetic Processed Materials with Transfer Learning and Reinforcement Learning Journal Article
In: no. DOE-UF-20384, 2024.
@article{Krause2024-tz,
title = {Elucidating Abnormal Grain Growth in Thermomagnetic Processed Materials with Transfer Learning and Reinforcement Learning},
author = {Amanda Krause and Michael Tonks and Joel Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&citation_for_view=Isf8yn0AAAAJ:PkcyUWeTMh0C},
year = {2024},
date = {2024-04-01},
urldate = {2024-04-01},
number = {DOE-UF-20384},
publisher = {Univ. of Florida, Gainesville, FL (United States)},
abstract = {The goal of this research program is to establish the mechanism
governing local grain boundary motion, which is needed to design
and process desirable microstructures for better performance, by
identifying the relative contributions of grain boundary (GB)
energy and mobility to grain growth. Classical models for grain
growth assume that the primary mechanism for reducing the total
interfacial energy is area reduction and that GB restructuring is
not significant. This assumption implies that grain growth is
locally driven by curvature. However, recent experimental
observations using new non-destructive 3D x-ray diffraction
microscopy techniques (3D-XRM) reveal that classic descriptors
(i.e., curvature, number of neighbors, grain size) do not predict
real grain growth. Instead, local GB motion appears to be
governed by its energy relative to its neighbors such that
low-energy boundaries replace those of higher energy. However,
simulations that incorporate GB energy anisotropy still fail to
reproduce these observations. These discrepancies suggest that
the common assumption for grain growth theory must be re-examined
to predict and, thus, control microstructure evolution in real
polycrystals. A significant challenge to testing this assumption
is due to anisotropic GB mobility. Mobility may cause abnormal
grain growth or affect the final grain shapes or growth rate but
its true contributions are unknown because it is difficult to
measure. For example, observations in Fe have found that grains
associated with high energy and high mobility boundaries tend to
experience abnormal grain growth, whereas abnormal grain growth
is associated with low energy …},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
governing local grain boundary motion, which is needed to design
and process desirable microstructures for better performance, by
identifying the relative contributions of grain boundary (GB)
energy and mobility to grain growth. Classical models for grain
growth assume that the primary mechanism for reducing the total
interfacial energy is area reduction and that GB restructuring is
not significant. This assumption implies that grain growth is
locally driven by curvature. However, recent experimental
observations using new non-destructive 3D x-ray diffraction
microscopy techniques (3D-XRM) reveal that classic descriptors
(i.e., curvature, number of neighbors, grain size) do not predict
real grain growth. Instead, local GB motion appears to be
governed by its energy relative to its neighbors such that
low-energy boundaries replace those of higher energy. However,
simulations that incorporate GB energy anisotropy still fail to
reproduce these observations. These discrepancies suggest that
the common assumption for grain growth theory must be re-examined
to predict and, thus, control microstructure evolution in real
polycrystals. A significant challenge to testing this assumption
is due to anisotropic GB mobility. Mobility may cause abnormal
grain growth or affect the final grain shapes or growth rate but
its true contributions are unknown because it is difficult to
measure. For example, observations in Fe have found that grains
associated with high energy and high mobility boundaries tend to
experience abnormal grain growth, whereas abnormal grain growth
is associated with low energy …

Joseph Melville, Vishal Yadav, Lin Yang, Amanda R Krause, Michael R Tonks, Joel B Harley
Anisotropic physics-regularized interpretable machine learning of microstructure evolution Journal Article
In: Computational materials science, vol. 238, no. 112941, pp. 112941, 2024.
@article{Melville2024-lu,
title = {Anisotropic physics-regularized interpretable machine learning of microstructure evolution},
author = {Joseph Melville and Vishal Yadav and Lin Yang and Amanda R Krause and Michael R Tonks and Joel B Harley},
url = {https://scholar.google.com/citations?view_op=view_citation&hl=en&user=Isf8yn0AAAAJ&sortby=pubdate&citation_for_view=Isf8yn0AAAAJ:kF1pexMAQbMC},
doi = {10.1016/j.commatsci.2024.112941},
year = {2024},
date = {2024-04-01},
urldate = {2024-04-01},
journal = {Computational materials science},
volume = {238},
number = {112941},
pages = {112941},
publisher = {Elsevier BV},
abstract = {Anisotropic Physics-Regularized Interpretable Machine Learning
Microstructure Evolution (APRIMME) is a general-purpose machine
learning solution for grain growth simulations. In prior work,
PRIMME employed a deep neural network to predict site-specific
migration as a function of its neighboring sites to model normal,
isotropic, grain growth behavior. This work aims to extend this
method by incorporating grain boundary misorientation-based grain
growth behavior. APRIMME is trained on anisotropic simulations
created using the Monte Carlo-Potts (MCP) model. The results of
this work are compared statistically using grain radius, number
of sides per grain, mean neighborhood misorientations, and the
standard deviation of triple junction dihedral angles, and are
found to match in most cases. The exceptions are small and seem
to be related to two causes: (1) the deterministic model of
APRIMME is learning from the stochastic simulations of MCP, which
seems to accentuate triple junction behaviors; and, (2) a bias
against very small grains is made evident in a quicker decrease
in grains than expected at the beginning of an APRIMME
simulation. APRIMME is also evaluated for its general ability to
capture anisotropic grain growth behavior by first investigating
different test case initial conditions, including a circle grain,
three grain, and hexagonal grain microstructures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Microstructure Evolution (APRIMME) is a general-purpose machine
learning solution for grain growth simulations. In prior work,
PRIMME employed a deep neural network to predict site-specific
migration as a function of its neighboring sites to model normal,
isotropic, grain growth behavior. This work aims to extend this
method by incorporating grain boundary misorientation-based grain
growth behavior. APRIMME is trained on anisotropic simulations
created using the Monte Carlo-Potts (MCP) model. The results of
this work are compared statistically using grain radius, number
of sides per grain, mean neighborhood misorientations, and the
standard deviation of triple junction dihedral angles, and are
found to match in most cases. The exceptions are small and seem
to be related to two causes: (1) the deterministic model of
APRIMME is learning from the stochastic simulations of MCP, which
seems to accentuate triple junction behaviors; and, (2) a bias
against very small grains is made evident in a quicker decrease
in grains than expected at the beginning of an APRIMME
simulation. APRIMME is also evaluated for its general ability to
capture anisotropic grain growth behavior by first investigating
different test case initial conditions, including a circle grain,
three grain, and hexagonal grain microstructures.