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- Creator:
- Liao, Jiankan, Deng, Sidi, Huan, Xun, and Cooper, Daniel R.
- Description:
- We apply Bayesian inference to reduce network structure uncertainty on material flow analysis (MFA) and demonstrate the methodology through a case study on U.S. steel flow. In addition, we derive an input/output-based analysis to conduct decision-making based on the uncertainty results from MFA
- Keyword:
- Bayesian inference, Network structure uncertainty, Bayesian model selection, and Input/output analysis
- Citation to related publication:
- Liao, Jiankan, Deng, Sidi, Xun Huan, and Daniel Cooper. "Bayesian Model Selection for Network Discrimination and Risk-informed Decision Making in Material Flow Analysis." arXiv preprint arXiv:2501.05556 (2025).
- Discipline:
- Engineering
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- Creator:
- Dorman, Cole J
- Description:
- CHIME provides accurate measurements while enabling inter-spacecraft calibration in constellation missions, offering a significantly more affordable alternative to traditional magnetometers without compromising measurement quality. The development of CHIME is motivated by the high number of magnetometers needed in spacecraft constellations that require a cost-effective commercial solution, as traditional, precise magnetometers are expensive and require complex ground and on-orbit calibration methods that depend on geomagnetic models or special conditions. CHIME Accuracy Calibration: - Various PNI RM3100s were used for data collection, each specified when used and how - Ground CHIME was used for experiments (50 turns per axis, hand wound) - Bartington HC1 500 mm Helmholtz coil was used for calibration baseline experiments. - Python 3.7+ Coil Homogeneity Simulations: - Python 3.7+ Optimal Calibration Pulse Parameters: - Python 3.7+ - ESA Swarm Simulation Data 50 Hz: Level 1B MAGx_HR ( https://swarm-diss.eo.esa.int). - ESA Swarm Simulation Data 1 Hz: Level 1B MAGx_LR. CHIME Calibration Accuracy Across Orbital Environments: - Python 3.7+ - ESA Swarm Simulation Data 50 Hz: Level 1B MAGx_HR ( https://swarm-diss.eo.esa.int). Comparison Simulations of Single Sensor Attitude Indepedent Calibration Methods: - Python 3.7+ - ESA Swarm Simulation Data 50 Hz: Level 1B MAGx_HR ( https://swarm-diss.eo.esa.int). Definitions: CHIME- protagonist of the dataset and accompanying manuscript, the self-calibrating magnetometer Scale Factor (SF), Non-Orthogonality (NO)- forms of magnetic sensor error PNI RM3100- internal magnetic sensor in CHIME Bartington HC1 Coil- calibration tool for the RM3100 and CHIME, a Helmholtz coil itself. ESA - European Space Agency and Updates: - March 2025: Changes to simulated calibration methodology, completed before publication initial submission or peer-review
- Keyword:
- magnetometer, calibration, Helmholtz, spacecraft, and remote sensing
- Citation to related publication:
- Dorman, C.J., Vata, J., Ojeda, L. V., Moldwin, M.B., The CHIME Magnetometer: A Self-Calibrating Approach for Enhanced Accuracy in Spaceborne Applications, Forthcoming.
- Discipline:
- Engineering
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- Creator:
- Wan, Zhiwen, Pannala, Sravan, Solbrig, Charles, Stefanopoulou, Anna G. , Siegel, Jason B. , and Lee, Junseo
- Description:
- Lithium-ion batteries with silicon/graphite (Si/Gr) anodes achieve higher energy densities but face challenges such as rapid capacity fade, resistance growth, and complex expansion behavior under various cycling conditions. This study systematically addresses these challenges through a comprehensive test matrix to investigate the effects of pressure, temperature, state-of-charge (SoC) windows, and charge rates (C-rates) on the evolution of expansion, resistance, and capacity behavior over the lifetime of the battery. Increasing the applied pressure between 34 and 172 kPa reduced both reversible and irreversible expansion per cycle, as well as resistance growth over time, without significantly impacting capacity fade. Electrochemical Impedance Spectroscopy (EIS) confirmed that increased pressure lowered initial solution resistance and mitigated the growth of the solution and solid electrolyte interphase (SEI) resistance. Elevated temperature (45°C) extended battery cycle life despite an initial increase in resistance. Under these conditions, the lifetime impedance increase was dominated by SEI resistance. Consistent with prior studies, operating in a narrow SoC window at high SoC minimized capacity loss. Additionally, charge rates up to 2C had a limited effect on the overall degradation trends. Incremental capacity analysis (ICA) and differential voltage analysis (DVA) identified lithium inventory loss (LLI) as the primary driver of pre-knee degradation, whereas post-knee degradation resulted from a combination of LLI and anode-active material loss, particularly silicon. The deeper understanding of degradation mechanisms in batteries with Si/Gr anodes provided by this work enables the optimal packaging design and selection of operating conditions for the battery management system to extend battery cycle life.
- Keyword:
- Lithium-ion Batteries, Si/Gr Anodes, Battery Expansion, Incremental Capacity Analysis, Differential Voltage Analysis, Electrochemical Impedance Spectroscopy, and Lifetime Degradation Metrics
- Citation to related publication:
- Z. Wan et al. Degradation and Expansion of Lithium-Ion Batteries with Silicon/Graphite Anodes: Impact of Pretension, Temperature, C-rate and State-of-Charge Window
- Discipline:
- Engineering
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- Creator:
- Lorenz, James, Hildner, Matthew, van den Bogert, William, Zhu, Bizhong, Yee, Stanley, Fazeli, Nima, and Shih, Albert J
- Description:
- A transient flow model is developed to predict the flow of high-viscosity fluid dispensing for precision direct ink writing (DIW) in additive manufacturing. Models for pump deformation and fluid friction to accurately predict the flow of a high-viscosity non-Newtonian fluid through a progressive cavity pump, static mixer, and a tapered nozzle are created. Inside the progressive cavity pump, the effect of elastic deformation on modeling high-viscosity fluid transient flow is included. Based on the Characteristic Method (CM) and boundary conditions for DIW, the continuity and momentum equations are numerically solved. Using deformation modeling and CM, the transient response of the DIW system with step changes to the input volumetric flow rate is modeled for both a tube and spiral static mixer. The transient response of the DIW output volumetric flow rate is recorded using flow and pressure sensors and found to match the flow model. The deformation and CM models are applied to predict the corner swelling of a 90º corner DIW tool path from trapezoidal motion planning with accelerations from 100 to 2000 mm/s2. The predicted corner swelling is matched with the actual corner swelling found through image processing of the 90º corner produced via DIW. The corner swelling is significant, ranging from 0.76 to 0.37 mm for a line width of 0.25 mm and a height of 0.15 mm, and represents the model’s ability to quantify print errors. This study demonstrates that the flow model can accurately predict the transient response of the DIW volumetric flow rate, which is foundational to high-fidelity flow control and compensation in precision DIW.
- Keyword:
- Additive manufacturing, Direct ink writing, Progressive cavity pumping, High-viscosity fluids, and Computational fluid dynamics
- Discipline:
- Engineering
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- Creator:
- Best, T. Kevin, Seelhoff, C. Andrew, Wensman, Jeffrey, and Gregg, Robert D.
- Description:
- The dataset was collected to assess the clinical benefits of the latest generation Össur Power Knee with and without phase-based control compared to traditional passive microprocessor-controlled knees. The study included seven above-knee amputee participants and examined performance across a series of sit/stand and walking experiments. Data captured includes event logs, processed inverse kinematics and dynamics data, scaled OpenSim skeletons for each session, and raw motion capture and force plate data for various test conditions (HKIC, OSSR, PRES). All data is text-based and can be viewed in any compatible text editor. Data can be visualized in OpenSim. The dataset is organized by subject and test condition. Each folder includes a scaled subject OpenSim skeleton (*_skeleton.osim), a marker file for a range of motion trial (*_range_of_motion.trc), and three test folders each containing: Event Logs (*.event_log.csv): Time-stamped records of experimental events. Inverse Kinematics Data (*_IK.mot): Joint angle trajectories. Inverse Dynamics Data (*_ID.mot): Joint moment trajectories. Raw Marker Data (*_markers.csv): 3D coordinates of motion capture markers. Ground Reaction Force Data (*_GRF.mot): Force plate measurements of ground reactions during movement tasks.
- Keyword:
- Robotic Prostheses, Transfemoral Amputees, and Prosthesis Control
- Citation to related publication:
- T. Kevin Best, C. Andrew Seelhoff, Jeffrey Wensman, Robert D. Gregg, "The Össur Power Knee with Phase-Based Control Provides Clinical Benefits over Passive Microprocessor Knees," Submitted to the Journal of NeuroEngineering and Rehabilitation, 2025.
- Discipline:
- Engineering and Health Sciences
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- Creator:
- Shanehsazzadeh, Faezeh, DeLancey, John, and Ashton-Miller, James
- Description:
- Urinary incontinence affects many women, yet there are no monitoring devices capable of accurately capturing flow dynamics during everyday activities. Building on our initial development of a wearable personal uroflowmeter, this study enhances the device's performance under realistic, dynamic conditions similar to those encountered in daily living. We integrated an optimized 8-vane Etoile flow conditioner with a 0.2D opening into the device. Both computational fluid dynamics simulations and experimental tests demonstrated that this flow conditioner significantly reduced turbulence intensity by 82% and stabilized the axial velocity profile by 67%, increasing the R² of flow rate measurements from 0.44 to 0.92. Furthermore, our machine learning frame-work—utilizing Support Vector Machines (SVM) and Extreme Gradient Boosting (XGBoost) models with Principal Component Analysis (PCA)—accurately predicted the true flow rate with high correlations and robust performance with minimal overfitting. For the test dataset, the SVM achieved a correlation of 0.86, an R² of 0.74, and an MAE of 2.8, whereas the XGBoost-PCA model exhibited slightly stronger performance, with a correlation of 0.88, an R² of 0.76, and an MAE of 2.6. These advances established a solid foundation for developing a reliable, wearable uroflowmeter capable of effectively monitoring urinary incontinence in real-world settings.
- Keyword:
- Uroflowmeter; Urinary Incontinence; Wearable Device; Dynamic Flow Conditions; Flow Conditioner; Machine Learning; Extreme Gradient Boosting; Support Vector Ma-chines;
- Discipline:
- Engineering
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- Creator:
- Jones, Kaylin, Fernández Correa, Mariana I., Malherbe, Julien, and Cotel, Aline J.
- Description:
- Sea lampreys (Petromyzon marinus) are an invasive species of concern in the Laurentian Great Lakes. Their predation on native species has degraded the ecological and economic health of the region. They are thus targeted for removal through various means, including trapping. Currently, sea lamprey traps are somewhat inefficient, believed to be partially due to their “entrance flows”, or the flow patterns induced by these traps that are felt by approaching sea lampreys. This study experimentally quantifies these flows. Models of two common sea lamprey trap designs were built and installed in a water tunnel in the University of Michigan Hydraulics Lab, and attraction flows were measured using Particle Image Velocimetry (PIV) with minimal background turbulence. Velocity, velocity gradient, and vorticity distributions in the flow are evaluated from the PIV data. These same models were installed in larger-scale raceways at USGS’ Hammond Bay Biological Station, and attraction flows were again measured using PIV to explore how these patterns change in a more turbulent environment that better mimics natural conditions. and Hammond Bay Biological Station (HBBS) is a research center that aims to develop control measures for sea lampreys and conduct research to aid native fish restoration. HBBS is a field station of the USGS Great Lakes Science Center (GLSC) managed by the Great Lakes Fishery Commission (GLFC). More information on HBBS can be found here: https://www.usgs.gov/centers/great-lakes-science-center/science/hammond-bay-biological-station.
- Keyword:
- Entrance Flows, sea lamprey, Great Lakes, hydrodynamics, invasive species, particle image velocimetry, sea lamprey, sea lamprey traps, and turbulence
- Citation to related publication:
- Jones, Kaylin, et. al. 2024. Investigating entrance hydrodynamics of sea lamprey traps. Canadian Journal of Fisheries and Aquatic Sciences. XX(X): XXX-XXX. https://doi.org/XX.XXXX/cjfas-XXXX.
- Discipline:
- Engineering
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- Creator:
- Zhu, Yongxian, Deng, Sidi, and Cooper, Daniel R
- Description:
- This dataset is curated as a byproduct of the "Material and Vehicle Design for High-Value Recycling of Aluminum and Steel Automotive Sheet" project, funded by the REMADE Institute of the Department of Energy and referred to as the "Clean Sheet Project" in the file "electricity scenarios slides.pptx." The dataset presents projected U.S. electricity emission factors (MJ primary energy or gCO2/kWh electricity delivered) under various scenarios, including different levels of uptake of the U.S. Inflation Reduction Act. The projections are based on estimated trends in the U.S. electricity generation mix, along with the authors' analysis of the energy and emission intensities of relevant power sources. The dataset supports research—particularly life cycle assessment—relying on U.S. regional energy profile and emissions factors.
- Keyword:
- Electricity Mix, Renewable Energy, Greenhouse Gas Emissions, Decarbonization, and Net-Zero
- Discipline:
- Engineering and General Information Sources
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- Creator:
- Ma, Zhenyu
- Description:
- Related research overview: Airborne transmission of infectious diseases poses a great threat to public health and the global economy, making the disinfection of airborne pathogens a priority. Detection of airborne pathogens, particularly their infectivity and changes thereof, can be challenging and labor-intensive. Laser-induced fluorescence (LIF) has been used to detect and characterize aerosols of biological origin. In this study, the fluorescence of MS2 bacteriophage aerosol is studied using aWideband Integrated Bioaerosol Sensor (WIBS). Infectivity assays and fluorescence measurements of viral aerosols are taken before and after non-thermal plasma (NTP) treatment. It is found that NTP treatment induces 1) infectivity loss for MS2 aerosol, 2) a change in aerosol fluorescence, and 3) viral protein damage. Increasing NTP applied voltage and power is positively correlated with infectivity loss and reduction in mean viral aerosol fluorescence intensity. The findings in this study suggest fast detection of airborne virus infectivity and protein damage is possible via aerosol fluorescence methods. and Description of files in the dataset: 20240716 repaired WIBS MS2 - size.xlsx - this file contains the particle fluorescence and size data for aerosolized viruses 20240729 PBSbuffer size&fluor.xlsx - this file contains the particle fluorescence and size data for the buffer (i.e. control) 20240812 repairedWIBS diffVoltage.pxp - this file contains the virus particle fluorescence data when exposed to plasmas of different voltages. This file also contains the instrument background fluorescence data measurements.
- Discipline:
- Science and Engineering
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- Creator:
- Mirshams Shahshahani, Payam
- Description:
- Please see Payam Mirshams Shahshahani's University of Michigan doctoral dissertation: https://deepblue.lib.umich.edu/bitstream/handle/2027.42/155254/mirshams_1.pdf?sequence=1
- Keyword:
- unipedal balance, hip muscle strength and endurance, age, hip moment
- Citation to related publication:
- Mirshams Shahshahani, Masteling and Ashton-Miller, article under review in IISE Transactions on Occupational Ergonomics & Human Factors, Supplement, Festschrift for Professor Thomas J. Armstrong
- Discipline:
- Engineering