Article
Environmental Sciences
Yue Zhao, Jian Luo
Summary: This research proposes a dimension-reduced quasi-Newton method within the geostatistical framework to lower computational costs by updating the approximate Jacobian of the forward model. The efficiency and validity of this approach are tested through numerical experiments, demonstrating its effectiveness in providing satisfactory inverse results.
WATER RESOURCES RESEARCH
(2021)
Article
Environmental Sciences
He Huang, Zhihua Chen, Tao Wang, Liang Zhang, Tianwen Liu, Gaoming Zhou
Summary: The study revealed that pore groundwater moves horizontally and rapidly, with synchronous response within an hour of groundwater level in upstream and downstream boreholes during riverbed dredging test; groundwater can vertically supply karst groundwater below, causing a one-week lasting groundwater level increase during the dry season test; injected tracer took more than seven months to eliminate, indicating a slow flow velocity in the karst aquifer.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Multidisciplinary
Chao-shuai Han, Xue-zheng Zhu, Jin Gu, Guo-hui Yan, Xiao-hui Gao, Qin-wen Zuo
Summary: This study improves the Four-Dimensional Variation source term inversion algorithm by introducing the observation error regularization factor. The estimation method of the observation error regularization factor based on Bayesian optimization is proposed. The experimental results show that the improved model achieves higher accuracy in estimating both source intensity and location compared to the previous algorithm.
DEFENCE TECHNOLOGY
(2023)
Article
Engineering, Civil
Mohammed Aliouache, Xiaoguang Wang, Pierre Fischer, Gerard Massonnat, Herve Jourde
Summary: The combination of tomographic pumping and flowmeter tests in an inverse approach allows for efficient characterization of three-dimensional aquifer properties, enhancing the realism of depositional features. This method offers a low-cost and rapid assessment of hydraulic properties in layered porous rocks, with good agreement between inverted hydraulic conductivity field and permeability measurements.
JOURNAL OF HYDROLOGY
(2021)
Article
Geosciences, Multidisciplinary
Dimitri Rambourg, Raphael Di Chiara, Philippe Ackerer
Summary: When modelling contamination transport in subsurface and aquifers, it is important to assess the heterogeneities of the porous medium and the vertical distribution of aquifer parameters. This study proposes a method that uses estimated hydraulic parameters from a 2D calibrated flow model as constraints for a 3D hydrogeological model. The method is tested using a synthetic model with known structure, and it successfully estimates parameters close to the known values.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Multidisciplinary Sciences
Kartik P. Iyer, Sachin S. Bharadwaj, Katepalli R. Sreenivasan
Summary: The study examines the circulation statistics around minimal area loops and finds that they only match those of planar loops circumscribing equivalent areas when normalized by an internal variable such as the standard deviation. This work highlights the previously unknown connection between minimal surfaces and turbulence.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Geosciences, Multidisciplinary
A. Pavlides, E. A. Varouchakis, D. T. Hristopulos
Summary: Mining activities can have a significant impact on groundwater reservoirs nearby. Different methods have been used to investigate the spatial variability of groundwater levels in mining areas, but face challenges such as small sample size, non-Gaussian data distribution, and clustering of sample locations near the mines. This research compares two stochastic methods, stochastic local interactions (SLI) and universal Kriging (UK), using water level data from 72 locations around three mines in Northern Greece. The results show that UK performs better overall, while SLI is slightly better for smaller sample sizes where reliable estimation of the variogram model is not possible.
HYDROGEOLOGY JOURNAL
(2023)
Article
Engineering, Civil
J. F. Martin-Rodriguez, M. Mudarra, B. De la Torre, B. Andreo
Summary: The joint use of statistical time-lag evaluation and dye tracer tests techniques is applied to assess the response time of a karst aquifer. This study aims to develop conceptual models on the hydrogeological functioning and establish a reference frame for predicting potential affections to springs from recharge events. By quantifying the empirical relationships between rainfall events intensity and time-lag in the springs, a reliable tool for predicting potential impacts on urban water supply is created. Additionally, comparing these relationships with results from tracer tests enhances the understanding of aquifer behavior and the influence of concentrated recharge.
JOURNAL OF HYDROLOGY
(2023)
Article
Computer Science, Interdisciplinary Applications
Byunguk Kim, Il Won Seo, Siyoon Kwon, Sung Hyun Jung, Yongju Choi
Summary: This study aimed to perform reactive transport modeling considering the reactivities of chemicals for sorption, volatilization, and biodegradation. The results showed that the volatility of solutes can lead to mass loss, while adsorption can delay the arrival time of substances.
ENVIRONMENTAL MODELLING & SOFTWARE
(2021)
Article
Chemistry, Multidisciplinary
Wenkai Liu, Songsong Chen, Yun Liu, Zhican Wen, Fuman Jiang, Zhongying Xue, Xing Wei, Yuehui Yu
Summary: A local three-dimensional model of heat and mass transfer is proposed for 300 mm Czochralski silicon crystal growth with a transverse magnetic field. The model includes a PID control system and main physical effects such as release of crystallization latent heat, crystallization interface correction, Marangoni effects, oxygen transport, and electromagnetic effects. A method for crystallization interface correction is developed, particularly suitable for non-axisymmetric flow when the crystal rotates. Simulation results show that temperature, growth-rate, and oxygen concentration on the crystallization interface are influenced by melt convection. The model is validated at different solidified fractions, and the simulation results of oxygen concentration are in good agreement with experimental results.
Article
Environmental Sciences
Asma El Ouni, Bo Guo, Hua Zhong, Mark L. Brusseau
Summary: The study successfully measured air-water interfacial areas in porous media using aqueous miscible-displacement column experiments, demonstrating good repeatability and accuracy of the test data under steady flow conditions.
Article
Biochemical Research Methods
Masataka Ohashi, Shin-ichi Maeda, Chikara Sato
Summary: In this study, we propose a method for three-dimensional reconstruction in cryogenic electron microscopy that utilizes structural symmetry as a constraint and employs iterative optimization with a single objective function to estimate subunit structure and helical parameters.
IEEE-ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS
(2023)
Article
Mechanics
Pranav Kumar Dileep, Jendrik-Alexander Troeger, Stefan Hartmann, Gerhard Ziegmann
Summary: This paper compares two analytical approaches to describe the deformation and resulting strains in fiber construction. The approaches are applied to experimental results and finite element computations. Furthermore, the paper determines material parameters using an image correlation system and proposes an indicator to improve specimen geometries.
COMPOSITE STRUCTURES
(2022)
Article
Biophysics
Esen Kocak, Aysegul Yildiz, Fusun Acarturk
Summary: 3D bioprinting is a technology that prints designed biological materials in three dimensions, with applications in producing tissues, organs, cells, and blood vessels for transplantation. It also finds uses in modeling, drug delivery systems, and drug screening. Despite limitations, this technology is of great significance in the medical field.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2021)
Article
Environmental Sciences
You Li, Yixuan Hou, Huan Tao, Hongying Cao, Xiaodong Liu, Ziwei Wang, Xiaoyong Liao
Summary: This article introduces a method called Variance-Octree-Kriging (VOK) to handle the three-dimensional interpolation problem of pollutants at contaminated sites. The VOK method is able to deal with the non-stationarity in variance of soil pollutants in the geographic space (G-space) and demonstrates higher interpolation accuracy in prediction.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Environmental
Mavrik Zavarin, Elliot Chang, Haruko Wainwright, Nicholas Parham, Rahul Kaukuntla, Jadallah Zouabe, Amanda Deinhart, Victoria Genetti, Sam Shipman, Frank Bok, Vinzenz Brendler
Summary: This paper presents a comprehensive data-to-model workflow, including the development of a FAIR sorption database and a data fitting workflow. The workflow efficiently optimizes surface complexation reaction constants and is used for parameterizing reactive transport models.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Environmental Sciences
Mohammad A. Moghaddam, Ty P. A. Ferre, Xingyuan Chen, Kewei Chen, Xuehang Song, Glenn Hammond
Summary: Temperature-based methods are widely used in hydrologic science to infer exchange flux, but they have limitations due to simplifying assumptions. Researchers conducted experiments to investigate the application and limitations of machine learning in inferring exchange flux, finding that machine learning methods need to perform well under perfect conditions before considering real data usage.
Review
Environmental Sciences
Dipankar Dwivedi, Carl Steefel, Bhavna Arora, Jill Banfield, John Bargar, Maxim Boyanov, Scott C. Brooks, Xingyuan Chen, Susan S. Hubbard, Dan Kaplan, Kenneth M. Kemner, Peter S. Nico, Edward J. O'Loughlin, Eric M. Pierce, Scott L. Painter, Timothy D. Scheibe, Haruko M. Wainwright, Kenneth H. Williams, Mavrik Zavarin
Summary: This paper reviews the extensive research conducted by the US Department of Energy at representative sites and testbeds, exploring the distribution of contaminants and nutrients in water resources and their interactions with carbon and nitrogen dynamics. The paper also describes state-of-the-art characterization approaches and models for predicting contaminant fate and transport.
ENVIRONMENTAL RESEARCH LETTERS
(2022)
Article
Engineering, Environmental
Aurelien O. Meray, Savannah Sturla, Masudur R. Siddiquee, Rebecca Serata, Sebastian Uhlemann, Hansell Gonzalez-Raymat, Miles Denham, Himanshu Upadhyay, Leonel E. Lagos, Carol Eddy-Dilek, Haruko M. Wainwright
Summary: In this study, a comprehensive machine learning framework called PyLEnM is developed for long-term groundwater contamination monitoring. The framework includes various utility functions and key ML innovations, such as time series clustering, automated model selection, and proxy-based spatial interpolation. The methodology is demonstrated using monitoring data at the Savannah River Site F-Area.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Environmental Sciences
Kewei Chen, Xingyuan Chen, Xuehang Song, Martin A. Briggs, Peishi Jiang, Pin Shuai, Glenn Hammond, Hongbin Zhan, John M. Zachara
Summary: Quantifying dynamic hydrologic exchange flows (HEFs) within river corridors that experience high-frequency flow variations caused by dam regulations is important for understanding the biogeochemical processes at the river water and groundwater interfaces. In this study, a data assimilation-based approach was developed to estimate the sub-daily flux under highly dynamic flow conditions using multi-depth temperature observations. The results showed that this method can accurately capture vertical sub-daily fluxes even in the presence of multidimensional flow. The approach was successfully applied to real field temperature data collected at the Hanford site.
WATER RESOURCES RESEARCH
(2022)
Article
Multidisciplinary Sciences
Sebastian Uhlemann, Baptiste Dafflon, Haruko Murakami Wainwright, Kenneth Hurst Williams, Burke Minsley, Katrina Zamudio, Bradley Carr, Nicola Falco, Craig Ulrich, Susan Hubbard
Summary: This study quantifies the relationships between bedrock geophysical/hydrological properties and geomorphological/vegetation indices using machine learning, based on the covariability analysis of above- and belowground features on a watershed scale. The results show that machine learning can estimate most of their covariability, but regions of lower variability in the input parameters provide better estimates, indicating a limitation of commonly applied geomorphological models.
Article
Water Resources
Heeho D. Park, Matthew Paul, Glenn E. Hammond, Albert J. Valocchi
Summary: Coupling multiphase flow with energy transport due to high temperature heat sources introduces significant challenges. The standard NR iteration may not converge, requiring more sophisticated optimization methods like trust-region. Trust-region methods, modified for Primary Variable Switching (PVS), successfully converge in simulations with high-temperature heat sources. The methods show strong scalability on both single and multiple nodes in an HPC cluster.
ADVANCES IN WATER RESOURCES
(2022)
Article
Environmental Sciences
Lea Enguehard, Nicola Falco, Myriam Schmutz, Michelle E. Newcomer, Joshua Ladau, James B. Brown, Laura Bourgeau-Chavez, Haruko M. Wainwright
Summary: Coastal wetlands in the Great Lakes Region, specifically along Lake Erie, were studied using a machine learning clustering approach to identify spatial regions with co-varied properties. The study found that topography, soil texture, and plant productivity influence the distribution of wetland land covers. Clustering analysis also revealed regions with distinct environmental characteristics and sensitivity to lake-level variations.
Article
Environmental Sciences
Dajie Sun, Haruko Wainwright, Ishita Suresh, Akiyuki Seki, Hiroshi Takemiya, Kimiaki Saito
Summary: In this paper, a methodology is developed to estimate the spatial and temporal distribution of radiation air dose rates around the Fukushima Daiichi Nuclear Power Plant (FDNPP). The temporal evolution of dose rates is found to have a log-linear decay trend and spatially correlated fluctuations. A random forest method is used to estimate the log-linear decay trend at each location, and a modified Kalman filter coupled with a Gaussian process model is developed to estimate the dose-rate time series at a given location and time. The method is applied to the Fukushima evacuation zone, and accurate spatial and temporal predictions of radiation dose-rate maps are obtained using limited spatiotemporal measurements.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2022)
Article
Environmental Sciences
Ian A. Shirley, Zelalem A. Mekonnen, Haruko Wainwright, Vladimir E. Romanovsky, Robert F. Grant, Susan S. Hubbard, William J. Riley, Baptiste Dafflon
Summary: Discontinuous permafrost environments exhibit strong spatial heterogeneity, impacting soil temperatures and vegetation composition, which in turn affect ecosystem productivity. Ignoring observed landscape heterogeneity can lead to significant prediction uncertainty and bias in high-latitude carbon budget predictions.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Fadji Z. Maina, Haruko M. Wainwright, Peter James Dennedy-Frank, Erica R. Siirila-Woodburn
Summary: This study introduces a holistic bottom-up hillslope clustering approach based on hydrodynamic response, capable of capturing recharge and discharge processes, and demonstrates good performance in experiments.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Glenn E. Hammond
Summary: As modern reactive transport simulators evolve, researchers need a platform to prototype new biogeochemical processes. The PFLOTRAN Reaction Sandbox is a tool that leverages modern Fortran to customize reaction formulas and test kinetic rate expressions.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2022)
Article
Geosciences, Multidisciplinary
Zexuan Xu, Rebecca Serata, Haruko Wainwright, Miles Denham, Sergi Molins, Hansell Gonzalez-Raymat, Konstantin Lipnikov, J. David Moulton, Carol Eddy-Dilek
Summary: In this study, a reactive transport model is developed to evaluate the impact of different climate change scenarios on contaminant plume conditions and groundwater well concentrations. The results indicate that the competition between dilution and remobilization significantly influences the sorption of uranium. By integrating climate modeling data and hydrogeochemistry models, the study enables the quantification of climate change impacts and assists in planning for climate resiliency efforts and site management.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Haruko M. Wainwright, Sebastian Uhlemann, Maya Franklin, Nicola Falco, Nicholas J. Bouskill, Michelle E. Newcomer, Baptiste Dafflon, Erica R. Siirila-Woodburn, Burke J. Minsley, Kenneth H. Williams, Susan S. Hubbard
Summary: In this study, a watershed zonation approach was developed to characterize watershed organization and functions by integrating multiple spatial data layers. The approach successfully identified watershed hillslope zones with unique property distributions and demonstrated their associations with zone-based functions. The results showed that the clustering methods used generated similar zoning patterns across the watershed, and the identified zones provided information about watershed functions.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Water Resources
Jiancong Chen, Baptiste Dafflon, Haruko M. Wainwright, Anh Phuong Tran, Susan S. Hubbard
Summary: Evapotranspiration (ET) is influenced by climate change and meteorological conditions. This study developed the concept of subseasonal regimes using Hidden Markov Models (HMM) to quantify the variability of seasonal and subseasonal events. Snowmelt and monsoon timing have an impact on regime transitions and duration, with earlier snowmelt potentially leading to decrease in subseasonal ET.
FRONTIERS IN WATER
(2022)