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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:
- 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:
- 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
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- Creator:
- Fu, Xun, Zhang, Bohao, Weber, Ceri J., Cooper, Kimberly L., Vasudevan, Ram, and Moore, Talia Y.
- Description:
- Tails used as inertial appendages induce body rotations of animals and robots---a phenomenon that is governed largely by the ratio of the body and tail moments of inertia. However, vertebrate tails have more degrees of freedom (e.g., number of joints, rotational axes) than most current theoretical models and robotic tails. To understand how morphology affects inertial appendage function, we developed an optimization-based approach that finds the maximally effective tail trajectory and measures error from a target trajectory. For tails of equal total length and mass, increasing the number of equal-length joints increased the complexity of maximally effective tail motions. When we optimized the relative lengths of tail bones while keeping the total tail length, mass, and number of joints the same, this optimization-based approach found that the lengths match the pattern found in the tail bones of mammals specialized for inertial maneuvering. In both experiments, adding joints enhanced the performance of the inertial appendage, but with diminishing returns, largely due to the total control effort constraint. This optimization-based simulation can compare the maximum performance of diverse inertial appendages that dynamically vary in moment of inertia in 3D space, predict inertial capabilities from skeletal data, and inform the design of robotic inertial appendages. and 2025-01-31: In this update, we include the code required to run the simulations and optimizations. We updated the readme file to reflect this addition
- Keyword:
- simulation, inertial maneuvering, caudal vertebrae, trajectory optimization, and reconfigurable appendages
- Citation to related publication:
- Xun Fu, Bohao Zhang, Ceri J. Weber, Kimberly L. Cooper, Ram Vasudevan, Talia Y. Moore. (in review) Jointed tails enhance control of three-dimensional body rotation.
- Discipline:
- Engineering and Science
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- Creator:
- An, Yifu
- Description:
- We have ported our MHD code, BATSRUS ( https://github.com/SWMFsoftware/BATSRUS), to the GPU. This dataset contains the input parameters and raw timing results for the Paper. To reproduce the results, please follow the instructions and use the software specifications contained in readme.txt. and Abstract: BATSRUS, our state-of-the-art extended magnetohydrodynamic code, is the most used and one of the most resource-consuming models in the Space Weather Modeling Framework. It has always been our objective to improve its efficiency and speed with emerging techniques, such as GPU acceleration. To utilize the GPU nodes on modern supercomputers, we port BATSRUS to GPUs with the OpenACC API. Porting the code to a single GPU requires rewriting and optimizing the most used functionalities of the original code into a new solver, which accounts for around 1% of the entire program in length. To port it to multiple GPUs, we implement a new message passing algorithm to support its unique block-adaptive grid feature. We conduct weak scaling tests on as many as 256 GPUs and find good performance. The program has 50-60% parallel efficiency on up to 256 GPUs, and up to 95% efficiency within a single node (4 GPUs). Running large problems on more than one node has reduced efficiency due to hardware bottlenecks. We also demonstrate our ability to run representative magnetospheric simulations on GPUs. The performance for a single A100 GPU is about the same as 270 AMD "Rome" CPU cores, and it runs 3.6 times faster than real time. The simulation can run 6.9 times faster than real time on four A100 GPUs.
- Keyword:
- BATSRUS, GPU, and MHD simulation
- Citation to related publication:
- An, Y., Chen, Y., Zhou, H., Gaenko, A. and Toth, G. (2024). BATSRUS GPU: Faster than Real Time Magnetospheric Simulations with a Block Adaptive Grid Code. Being revised. A preprint is available at http://arxiv.org/abs/2501.06717.
- Discipline:
- Engineering