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- Creator:
- Crisp, Dakota N., Parent, Rachel, Nakatani, Mitsuyoshi, Murphy, Geoffrey G. , and Stacey, William C.
- Description:
- This data and scripts are meant to test and show that seizure onset dynamics can be modulated using anti-epileptic drugs. A zip file is included that contains all waveform data, MATLAB processing scripts, and metadata. The MATLAB scripts allow for visual review validation and objective feature analysis. The file includes various README files explaining the scripts and their relationships in greater detail.
- Keyword:
- Bifurcation, Epilepsy, Seizure, and Electrophysiology
- Discipline:
- Health Sciences, Engineering, and Science
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- Creator:
- Nikolov, Denislav P, Srivastava, Siddhartha, Abeid, Bachir A, Scheven, Ulrich M, Arruda, Ellen M, Garikipati, Krishna, and Estrada, Jonathan B
- Description:
- Contemporary material characterisation techniques that leverage deformation fields and the weak form of the equilibrium equations face challenges in the numerical solution procedure of the inverse characterisation problem. As material models and descriptions differ, so too must the approaches for identifying parameters and their corresponding mechanisms. The widely-used Ogden material model can be comprised of a chosen number of terms of the same mathematical form, which presents challenges of parsimonious representation, interpretability, and stability. Robust techniques for system identification of any material model are important to assess and improve experimental design, in addition to their centrality to forward computations. Using fully 3D displacement fields acquired in silicone elastomers with our recently-developed magnetic resonance cartography (MR-u) technique on the order of ~20,000 points per sample, we leverage PDE-constrained optimisation as the basis of variational system identification of our material parameters. We incorporate the statistical F-test to maintain parsimony of representation. Using a new, local deformation decomposition locally into mixtures of biaxial and uniaxial tensile states, we evaluate experiments based on an analytical sensitivity metric, and discuss the implications for experimental design. This repository contains the acquired data and MRI processing code used in this work.
- Keyword:
- continuum mechanics, magnetic resonance, sensitivity, full-field deformations, physics inference, mechanics, mechanical engineering, and computational mechanics
- Citation to related publication:
- https://doi.org/10.48550/arXiv.2204.03122
- Discipline:
- Engineering
-
- Creator:
- BIRDS Lab, U. Michigan
- Description:
- These data were produced in an attempt to characterize the turning and steering behaviors of 1-DoF multi-legged (hexpedal in this case) robots. Such turning behaviors require sliding contact points. All the data is provided in a single, large .csv.gz file (416256 rows); additional details and example code in the README
- Keyword:
- robot, multilegged, and steering
- Citation to related publication:
- BIRDS Lab, U. BigAnt v6 robot motion tracking data - RAW dataset [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/024q-kk06, Revzen, S., & Guckenheimer, J. (2008). Estimating the phase of synchronized oscillators. Phys. Rev. E, 78, 051907. http://dx.doi.org/10.1103/PhysRevE.78.051907, and Dan Zhao and Shai Revzen 2020 Bioinspir. Biomim. 15 045001 https://doi.org/10.1088/1748-3190/ab84c0
- Discipline:
- Engineering
-
- Creator:
- Mukhopadhyay, Agnit, Daniel T Welling, Michael W Liemohn, Aaron J Ridley, Shibaji Chakrabarty, and Brian J Anderson
- Description:
- An updated auroral conductance module is built for global models, using nonlinear regression & empirical adjustments to span extreme events., Expanded dataset raises the ceiling of conductance values, impacting the ionospheric potential dB/dt & dB predictions during extreme events., and Application of the expanded model with empirical adjustments refines the conductance pattern, and improves dB/dt predictions significantly.
- Keyword:
- Space Weather Forecasting, Extreme Weather, Ionosphere, Magnetosphere, MI Coupling, Ionospheric Conductance, Auroral Conductance, Aurora, SWMF, SWPC, Nonlinear Regression, and dB/dt
- Citation to related publication:
- Mukhopadhyay, A., Welling, D. T., Liemohn, M. W., Ridley, A. J., Chakraborty, S., & Anderson, B. J. (2020). Conductance Model for Extreme Events: Impact of Auroral Conductance on Space Weather Forecasts. Space Weather, 18(11), e2020SW002551. https://doi.org/10.1029/2020SW002551
- Discipline:
- Engineering and Science
-
- Creator:
- Smith, Joeseph P., Gronewold, Andrew D., Read, Laura, Crooks, James L., School for Environment and Sustainability, University of Michigan, Department of Civil and Environmental Engineering, University of Michigan, and Cooperative Institute for Great Lakes Research
- Description:
- Using the statistical programming package R ( https://cran.r-project.org/), and JAGS (Just Another Gibbs Sampler, http://mcmc-jags.sourceforge.net/), we processed multiple estimates of the Laurentian Great Lakes water balance components -- over-lake precipitation, evaporation, lateral tributary runoff, connecting channel flows, and diversions -- feeding them into prior distributions (using data from 1950 through 1979), and likelihood functions. The Bayesian Network is coded in the BUGS language. Water balance computations assume that monthly change in storage for a given lake is the difference between beginning of month water levels surrounding each month. For example, the change in storage for June 2015 is the difference between the beginning of month water level for July 2015 and that for June 2015., More details on the model can be found in the following summary report for the International Watersheds Initiative of the International Joint Commission, where the model was used to generate a new water balance historical record from 1950 through 2015: https://www.glerl.noaa.gov/pubs/fulltext/2018/20180021.pdf. Large Lake Statistical Water Balance Model (L2SWBM): https://www.glerl.noaa.gov/data/WaterBalanceModel/, and This data set has a shorter timespan to accommodate a prior which uses data not used in the likelihood functions.
- Keyword:
- Water, Balance, Great Lakes, Laurentian, Machine, Learning, Lakes, Bayesian, and Network
- Citation to related publication:
- Smith, J., Gronewald, A. et al. Summary Report: Development of the Large Lake Statistical Water Balance Model for Constructing a New Historical Record of the Great Lakes Water Balance. Submitted to: The International Watersheds Initiative of the International Joint Commission. Accessible at https://www.glerl.noaa.gov/pubs/fulltext/2018/20180021.pdf, Large Lake Statistical Water Balance Model (L2SWBM). https://www.glerl.noaa.gov/data/WaterBalanceModel/, and Gronewold, A.D., Smith, J.P., Read, L. and Crooks, J.L., 2020. Reconciling the water balance of large lake systems. Advances in Water Resources, p.103505.
- Discipline:
- Science and Engineering
-
- Creator:
- van Velden, Grace and Reddy, Raghav
- Description:
- A household survey was developed to capture household perceptions and behaviors around drinking water use. It consisted of several modules: key informant and household demographics, household assets and consumption, water use behaviors in the dry season, water use behaviors during the rest of the year, and water supply maintenance and repair. Intervention and safe water device surveys were also developed; the household and intervention surveys were administered via Qualtrics. and This record consists of several survey instruments, exported where appropriate from Qualtrics into PDF and .qsf.
- Keyword:
- Bangladesh, arsenic, sustainability, survey
- Discipline:
- Engineering
-
- Creator:
- Huang, Cheng MI
- Description:
- A 2D planar representation of a generic laboratory-scale combustor is established to assess the capabilities of ROMs for representing realistic combustion flowfields. The purpose of this dataset is to provide a testbed to build reduced model for relevant challenging reacting flow problems using different methods. The dataset was generated under the Air Force Center of Excellence on Multi-Fidelity Modeling of Rocket Combustion Dynamics and the goal of the center is to advance the state-of-the-art in Reduced Order Models (ROMs) and enable efficient prediction of instabilities in liquid fueled rocket combustion systems., Detailed documentation of how the data is generated can be found in: https://afcoe.engin.umich.edu/benchmark-data. Instrument and/or Software specifications: - recommendation: Matlab and Tecplot. , 1. Data_150000to159999.tar: the unsteady flow field data from time step 150000 to 159999 (time increment, dt, between each time step is 1E-7 sec). 2. Data_160000to169999.tar: the unsteady flow field data from time step 160000 to 169999 (time increment, dt, between each time step is 1E-7 sec). , 3. Data_170000to179999.tar: the unsteady flow field data from time step 170000 to 179999 (time increment, dt, between each time step is 1E-7 sec). 4. Data_180000to189999.tar: the unsteady flow field data from time step 180000 to 189999 (time increment, dt, between each time step is 1E-7 sec)., 5. Data_190000to199999.tar: the unsteady flow field data from time step 190000 to 199999 (time increment, dt, between each time step is 1E-7 sec). 6. Data_200000to209999.tar: the unsteady flow field data from time step 200000 to 209999 (time increment, dt, between each time step is 1E-7 sec). , 7. Data_210000to219999.tar: the unsteady flow field data from time step 210000 to 219999 (time increment, dt, between each time step is 1E-7 sec). 8. Data_220000to229999.tar: the unsteady flow field data from time step 220000 to 229999 (time increment, dt, between each time step is 1E-7 sec). , and 9. grid.dat: the topology of the CFD mesh used to generate this data (can be directly loaded in Tecplot). 10. the file "sample_code.zip" contains the sample Matlab scripts to load and output the .dat files to help the researchers to get started. To run the script, the software Matlab is required and the researchers can simply run sampleIO.m script in Matlab to test the code.
- Citation to related publication:
- McQuarrie, S., Huang, C., and Willcox, K., Data-driven reduced-order models via regularised Operator Inference for a single-injector combustion process, Journal of the Royal Society of New Zealand, 2021. (code available: https://github.com/Willcox-Research-Group/ROM-OpInf-Combustion-2D)., McQuarrie, S. A., Huang, C., & Willcox, K. E. (2021). Data-driven reduced-order models via regularised Operator Inference for a single-injector combustion process. Journal of the Royal Society of New Zealand, 51(2), 194–211. https://doi.org/10.1080/03036758.2020.1863237 , Swischuk, R., Kramer, B., Huang, C., & Willcox, K. (2020). Learning Physics-Based Reduced-Order Models for a Single-Injector Combustion Process. AIAA Journal, 58(6), 2658–2672. https://doi.org/10.2514/1.J058943, Huang, C., Duraisamy, K., & Merkle, C. L. (2019). Investigations and Improvement of Robustness of Reduced-Order Models of Reacting Flow. AIAA Journal, 57(12), 5377–5389. https://doi.org/10.2514/1.J058392 , and Harvazinski, M. E., Huang, C., Sankaran, V., Feldman, T. W., Anderson, W. E., Merkle, C. L., & Talley, D. G. (2015). Coupling between hydrodynamics, acoustics, and heat release in a self-excited unstable combustor. Physics of Fluids, 27(4), 045102. https://doi.org/10.1063/1.4916673
- Discipline:
- Engineering
-
- Creator:
- Troesch, Armin, W. and Kang, C.-G.
- Description:
- This scaled acceleration time series has been used in the graduate class, NA540, as an example of hydrodynamic impact. For a more detailed description of the tests, please see: Troesch, A.W. and Kang, C.-G., "Hydrodynamic Impact Loads on Three Dimensional Bodies," Proceedings of the 16th Symposium on Naval Hydrodynamics, Berkeley, July 1986, National Academy Press, Washington, D.C., 1987, pp. 537-558.
- Keyword:
- hydrodynamic impact
- Citation to related publication:
- Troesch, A.W. and Kang, C.-G., "Hydrodynamic Impact Loads on Three Dimensional Bodies," Proceedings of the 16th Symposium on Naval Hydrodynamics, Berkeley, July 1986, National Academy Press, Washington, D.C., 1987, pp. 537-558. This item is not available online due to copyright restrictions, but the text can be searched using Hathi Trust: https://babel.hathitrust.org/cgi/pt?id=mdp.39015040312475
- Discipline:
- Engineering and Science
-
- Creator:
- Moore, Talia Y, Villacis Nunez, C Nathaly, Ray, Andrew P, and Cooper, Kimberly L
- Description:
- Hind limbs can undergo dramatic changes in loading conditions during the transition from quadrupedal to bipedal locomotion. For example, the most early diverging bipedal jerboas (Rodentia: Dipodidae) are some of the smallest mammals in the world, with body masses that range 2-4 grams. The larger jerboa species exhibit developmental and evolutionary fusion of the central three metatarsals into a single cannon bone. We hypothesize that body size reduction and metatarsal fusion are mechanisms to maintain the safety factor of the hind limb bones despite the higher ground reaction forces associated with bipedal locomotion. Using finite element analysis to model collisions between the substrate and the metatarsals, we found that body size reduction was insufficient to reduce bone stress on unfused metatarsals, based on the scaled dynamics of larger jerboas, and that fused bones developed lower stresses than unfused bones when all metatarsals are scaled to the same size and loading conditions. Based on these results, we conclude that fusion reinforces larger jerboa metatarsals against high ground reaction forces. Because smaller jerboas with unfused metatarsals develop higher peak stresses in response to loading conditions scaled from larger jerboas, we hypothesize that smaller jerboas use alternative dynamics of bipedal locomotion that reduces the impact of collisions between the foot and substrate.
- Keyword:
- finite element, functional morphology, bipedal, jerboa, metatarsus, and bone fusion
- Citation to related publication:
- Villacis Nunez, Ray, Cooper, Moore (submitted). Body size reduction and metatarsal fusion were distinct mechanisms to resist bending as jerboas (Dipodidae) transitioned from quadrupedal to bipedal.
- Discipline:
- Science and Engineering
-
- Creator:
- Curlis, JD, Renney, TJ, Davis Rabosky, AR, and Moore, TY
- Description:
- Efficient comparisons of biological color patterns are critical for understanding the mechanisms by which organisms evolve in ecosystems, including sexual selection, predator-prey interactions, and thermoregulation. However, elongate or spiral-shaped organisms do not conform to the standard orientation and photographic techniques required for automated analysis. Currently, large-scale color analysis of elongate animals requires time-consuming manual landmarking, which reduces their representation in coloration research despite their ecological importance. We present Batch-Mask: an automated and customizable workflow to facilitate the analysis of large photographic data sets of non-standard biological subjects. First, we present a user guide to run an open-source region-based convolutional neural network with fine-tuned weights for identifying and isolating a biological subject from a background (masking). Then, we demonstrate how to combine masking with existing manual visual analysis tools into a single streamlined, automated workflow for comparing color patterns across images. Batch-Mask was 60x faster than manual landmarking, produced masks that correctly identified 96% of all snake pixels, and produced pattern energy results that were not significantly different from the manually landmarked data set. The fine-tuned weights for the masking neural network, user guide, and automated workflow substantially decrease the amount of time and attention required to quantitatively analyze non-standard biological subjects. By using these tools, biologists will be able to compare color, pattern, and shape differences in large data sets that include significant morphological variation in elongate body forms. This advance will be especially valuable for comparative analyses of natural history collections, and through automation can greatly expand the scale of space, time, or taxonomic breadth across which color variation can be quantitatively examined.
- Keyword:
- convolutional neural network, photography, sensory ecology, color evolution, vision, and image segmentation
- Citation to related publication:
- Curlis, Renney, Davis Rabosky, Moore (submitted) Batch-Mask: An automated Mask R-CNN workflow to isolate non-standard biological specimens for color pattern analysis.
- Discipline:
- Engineering and Science
-
- Creator:
- Brady P. Strabel
- Description:
- The contained data comprises what was collected during the characterization of the quad-magnetometer as described in 'Quad-Mag Board for CubeSat Applications'. There are approximately 38 hours of data that compromise a stability test, 10 hours of noise floor testing data, and 10 minutes of sensitivity testing data. Each data file has three-axis measurements from four individual magnetometers over the specified time period at a 65 Hz sampling rate.
- Keyword:
- Magnetometer, COTS, and CubeSat
- Citation to related publication:
- Strabel, B. P., Regoli, L. H., Moldwin, M. B., Ojeda, L. V., Shi, Y., Thoma, J. D., Narrett, I. S., Bronner, B., and Pellioni, M.: Quad-Mag board for CubeSat applications, Geosci. Instrum. Method. Data Syst., 11, 375–388, https://doi.org/10.5194/gi-11-375-2022, 2022.
- Discipline:
- Engineering
-
- Creator:
- Minallah, Samar and Steiner, Allison L.
- Description:
- Data format: netcdf4 , Time series duration: 2016-06-01 to 2020-10-31, Temporal resolution: Daily, and Spatial resolution: The model output was regridded to a 0.05 degree rectilinear (lat/lon) grid using the conservative remapping method ("cdo remapcon" tool).
- Keyword:
- Land surface hydrology, Great Lakes, Land surface model, NOAH-MP, WRF-Hydro, and Hydrologic modeling
- Citation to related publication:
- Minallah, S. (2022). A Study on the Atmospheric, Cryospheric, and Hydrologic Processes Governing the Evolution of Regional Hydroclimates (Doctoral dissertation, University of Michigan Ann Arbor). https://dx.doi.org/10.7302/6223
- Discipline:
- Science and Engineering
-
- Creator:
- Figueroa, C. Alberto
- Description:
- This information provides the data and commands to manually setup the computational simulations used in the PLOS ONE paper 'Patient-specific modeling of right coronary circulation vulnerability post-liver transplant in Alagille’s syndrome' using CRIMSON (CARDIOVASCULAR INTEGRATED MODELLING & SIMULATION) a prototype simulation environment developed under the support of the European Research Council (( http://www.crimson.software/)., Note that a Windows version of the CRIMSON flowsolver is provided as part of the CRIMSON Windows installer, but you will need a very powerful Windows computer to run these simulations, as the models used in the present work are extremely computationally-demanding. It is recommended that you use a Linux version of the CRIMSON flowsolver on a high-performance computer., Option 1 (ready-to-use files to immediately start the simulation): 1. Please unzip the Ready-to-use files. 2. Copy the folders of each of the three conditions to the high performance computer. 3. In addition to different codes used, each folder provides the boundary conditions applied in the simulations described in the manuscript (e.g. LPN parameters). To run the 3D simulations for each condition simply launch the it using the CRIMSON flowsolver. In addition, the solver.inp file can be modified to run a 0D "real-time simulation" (please open solver.inp with a text editor and modify line 4 "Simulate in Purely Zero Dimensions:" to "True")., Option 2 (using the MITK files): 1. Please download and install Crimson software ( http://www.crimson.software/). 2. Please unzip the MITK files and the Ready-to-use files. 3. From amongst the provided MITK files, load the MITK file of interest to CRIMSON (using the MITK files, additional changes can be made to the computational model in case the user wants to explore different settings/boundary conditions e.g. change the vascular wall properties, introducing a change in the geometry to create a virtual stenosis). 3. Navigate to the tree in the "Data Manager" panel and select the "Pulmonaries", "CRIMSON SOLVER" and then "Solver study 3D" items, in the described order. 4. In the right hand panel select the "CRIMSON Solver setup" tab and scroll down the right hand bar until to find the "Setup Solver" box; click to output the simulation files (faceInfo.dat, geombc.dat.1, multidomain.dat, netlist_surface.dat,numstart.dat, presolver folder, solver.inp, restart.0.1). 5. Copy and replace the geombc.dat.1 and restart.0.1 generated by CRIMSON for each individual condition to the respective unziped folder in the Ready-to-use file (discard the remaining files that were output by CRIMSON). Note that if you have not changed anything about the model (e.g. vascular wall properties), then doing this will produce restart.0.1 and geombc.dat.1 files which are identical to the ready-to-use versions. 6. Finally copy each Condition folder to the high performance computer and simply launch the simulation using the CRIMSON flowsolver., and For technical queries please contact crimson-users@googlegroups.com. --October 2018.
- Citation to related publication:
- Silva Vieira M, Arthurs CJ, Hussain T, Razavi R, Figueroa CA (2018) Patient-specific modeling of right coronary circulation vulnerability post-liver transplant in Alagille’s syndrome. PLOS ONE 13(11): e0205829. https://doi.org/10.1371/journal.pone.0205829
- Discipline:
- Engineering and Health Sciences
-
- Creator:
- Crisp, Dakota N., Cheung, Warwick, Gliske, Stephen V., Lai, Alan, Freestone, Dean R., Grayden, David B., Cook, Mark J., and Stacey, William C.
- Description:
- The data and the scripts are to show that seizure onset dynamics and evoked responses change over the progression of epileptogenesis defined in this intrahippocampal tetanus toxin rat model. All tests explored in this study can be repeated with the data and scripts included in this repository. and Dataset citation: Crisp, D.N., Cheung, W., Gliske, S.V., Lai, A., Freestone, D.R., Grayden, D.B., Cook, MJ., Stacey, W.C. (2019). Epileptogenesis modulates spontaneous and responsive brain state dynamics [Data set]. University of Michigan Deep Blue Data Repository. https://doi.org/10.7302/r6vg-9658
- Keyword:
- evoked response, stimulation, bifurcation, epilepsy, seizure, divergence, and dynamics
- Citation to related publication:
- Crisp, D. N., Cheung, W., Gliske, S. V., Lai, A., Freestone, D. R., Grayden, D. B., Cook, M. J., & Stacey, W. C. (2020). Quantifying epileptogenesis in rats with spontaneous and responsive brain state dynamics. Brain Communications, 2(1). https://doi.org/10.1093/braincomms/fcaa048
- Discipline:
- Science, Engineering, and Health Sciences
-
- Creator:
- Siegel, Jason B. , Stefanopoulou, Anna G., and McKahn, Denise (McKay)
- Description:
- This section contains work related to the modeling of voltage degradation in a 24 cell PEM fuel cell stack with 300 cm2 cross-sectional area. The experimental hardware used to validate the model consists of a computer controlled system that coordinates air, hydrogen, cooling, and electrical subsystems to operate the stack. Dry hydrogen is pressure regulated for full utilization in the dead-ended anode. Using a solenoid valve, the anode is periodically purged to recover the gradual degradation in voltage. A membrane based humidifier controls the vapor content of the cathode gas stream while a mass flow controller is used to regulate the flow to the desired stoichiometry.
- Citation to related publication:
- Denise A. McKay, Jason B. Siegel, William Ott, and Anna G. Stefanopoulou. Parameterization and prediction of temporal fuel cell voltage behavior during flooding and drying conditions. Journal of Power Sources, 178(1):207 - 222, 2008. https://doi.org/10.1016/j.jpowsour.2007.12.031
- Discipline:
- Engineering
-
- Creator:
- Bowen Li, Yiling Zhang, Siqian Shen, and Johanna Mathieu
- Description:
- The project outputs summarize all the publications, talks, and codes we accomplished under this NSF funding. In the project, we develop methodologies to manage uncertainty in future electric power systems and quantify how uncertainty affects power system sustainability. and Talks, papers, and poster in Deep Blue: http://hdl.handle.net/2027.42/149653
- Keyword:
- chance constraint, distributionally robust optimization, optimal power flow, demand response, and unimodality
- Citation to related publication:
- B. Li and J. L. Mathieu, "Analytical reformulation of chance-constrained optimal power flow with uncertain load control," 2015 IEEE Eindhoven PowerTech, Eindhoven, 2015, pp. 1-6. https://doi.org/10.1109/PTC.2015.7232803, B. Li, J. L. Mathieu and R. Jiang, "Distributionally Robust Chance Constrained Optimal Power Flow Assuming Log-Concave Distributions," 2018 Power Systems Computation Conference (PSCC), Dublin, 2018, pp. 1-7. https://doi.org/10.23919/PSCC.2018.8442927, B. Li, M. Vrakopoulou and J. L. Mathieu, "Chance Constrained Reserve Scheduling Using Uncertain Controllable Loads Part II: Analytical Reformulation," in IEEE Transactions on Smart Grid, vol. 10, no. 2, pp. 1618-1625, March 2019. https://doi.org/10.1109/TSG.2017.2773603, B. Li, R. Jiang and J. L. Mathieu, "Distributionally Robust Chance-Constrained Optimal Power Flow Assuming Unimodal Distributions With Misspecified Modes," in IEEE Transactions on Control of Network Systems, vol. 6, no. 3, pp. 1223-1234, Sept. 2019. https://doi.org/10.1109/TCNS.2019.2930872, B. Li, R. Jiang and J. L. Mathieu, "Distributionally robust risk-constrained optimal power flow using moment and unimodality information," 2016 IEEE 55th Conference on Decision and Control (CDC), Las Vegas, NV, 2016, pp. 2425-2430. https://doi.org/10.1109/CDC.2016.7798625, B. Li, S. D. Maroukis, Y. Lin and J. L. Mathieu, "Impact of uncertainty from load-based reserves and renewables on dispatch costs and emissions," 2016 North American Power Symposium (NAPS), Denver, CO, 2016, pp. 1-6. https://doi.org/10.1109/NAPS.2016.7747830, G. Martínez, J. Liu, B. Li, J. L. Mathieu and C. L. Anderson, "Enabling renewable resource integration: The balance between robustness and flexibility," 2015 53rd Annual Allerton Conference on Communication, Control, and Computing (Allerton), Monticello, IL, 2015, pp. 195-202. https://doi.org/10.1109/ALLERTON.2015.7447004, J. Liu, M. G. Martinez, B. Li, J. Mathieu and C. L. Anderson, "A Comparison of Robust and Probabilistic Reliability for Systems with Renewables and Responsive Demand," 2016 49th Hawaii International Conference on System Sciences (HICSS), Koloa, HI, 2016, pp. 2373-2380. https://doi.org/10.1109/HICSS.2016.297, Li, B., Jiang, R. & Mathieu, J.L. "Ambiguous risk constraints with moment and unimodality information." Math. Program. 173, 151–192 (2019). https://doi.org/10.1007/s10107-017-1212-x, M. Vrakopoulou, B. Li and J. L. Mathieu, "Chance Constrained Reserve Scheduling Using Uncertain Controllable Loads Part I: Formulation and Scenario-Based Analysis," in IEEE Transactions on Smart Grid, vol. 10, no. 2, pp. 1608-1617, March 2019. https://doi.org/10.1109/TSG.2017.2773627, Y. Zhang, S. Shen and J. L. Mathieu, "Data-driven optimization approaches for optimal power flow with uncertain reserves from load control," 2015 American Control Conference (ACC), Chicago, IL, 2015, pp. 3013-3018. https://doi.org/10.1109/ACC.2015.7171795, Y. Zhang, S. Shen and J. L. Mathieu, "Distributionally Robust Chance-Constrained Optimal Power Flow With Uncertain Renewables and Uncertain Reserves Provided by Loads," in IEEE Transactions on Power Systems, vol. 32, no. 2, pp. 1378-1388, March , and Y. Zhang, S. Shen, B. Li and J. L. Mathieu, "Two-stage distributionally robust optimal power flow with flexible loads," 2017 IEEE Manchester PowerTech, Manchester, 2017, pp. 1-6. https://doi.org/10.1109/PTC.2017.7981202
- Discipline:
- Engineering
-
- Creator:
- Chen, Yang and Manchester, Ward IV
- Description:
- GOES_flare_list: contains a list of more than 10,000 flare events. The list has 6 columns, flare classification, active region number, date, start time end time, emission peak time, GOES_B_flare_list: contains time series data of SDO/HMI SHARP parameters for B class solar flares , GOES_MX_flare_list: contains time series data of SDO/HMI SHARP parameters for M and X class solar flares, SHARP_B_flare_data_300.hdf5 and SHARP_MX_flare_data_300.hdf5 files contain time series more than 20 physical variables derived from the SDO/HMI SHARP data files. These data are saved at a 12 minute cadence and are used to train the LSTM model., and B_HARPs_CNNencoded_part_xxx.hdf5 and M_X HARPs_CNNencoded_part_xxx.hdf5 include neural network encoded features derived from vector magnetogram images derived from the Solar Dynamics Observatory (SDO) Helioseismic and Magnetic Imager (HMI). These data files typically contains one or two sequences of magnetograms covering an active region for a period of 24h with a 1 hour cadence. We encode each magnetogram with frames of a fixed size of 8x16 with 512 channels.
- Keyword:
- machine learning, data science, and solar flare prediction
- Citation to related publication:
- Chen, Y., Manchester, W., Hero, A., Toth, G., DuFumier, B. Zhou, T., Wang, X., Zhu, H., Sun, Zeyu, Gombosi, T., Identifying Solar Flare Precursors Using Time Series of SDO/HMI Images and SHARP Parameters, Space Weather, 17, 1404–1426. https://doi.org/10.1029/2019SW002214 and Jiao, Z., Chen, Y., Manchester, W. (2020). Data for Solar Flare Intensity Prediction with Machine Learning Models [Data set]. University of Michigan - Deep Blue. https://doi.org/10.7302/b07j-bj08
- Discipline:
- Engineering and Science
-
- Creator:
- Holmes, Patrick
- Description:
- This work was collected to evaluate Stability Basins for characterizing the limits of human stability during Sit-to-Stand. and MATLAB code was used to process the data into individual trials. Trials are labeled by Sit-to-Stand type (Natural, Momentum-Transfer, or Quasi-Static) and experimental condition. MATLAB code for analyzing the data and computing Stability Basins is provided. A GUI is provided to animate a subject's movement and display projections of the Stability Basins in the horizontal and vertical planes.
- Keyword:
- biomechanics, mathematical model, locomotion, fall risk, reachability, and feedback control
- Citation to related publication:
- https://arxiv.org/abs/1908.01876 and Holmes, P. D., Danforth, S. M., Fu, X.-Y., Moore, T. Y., & Vasudevan, R. (n.d.). Characterizing the limits of human stability during motion: Perturbative experiment validates a model-based approach for the Sit-to-Stand task. Royal Society Open Science, 7(1), 191410. https://doi.org/10.1098/rsos.191410
- Discipline:
- Engineering
-
- Creator:
- Ahluwalia, Vinayak S., Steimle, Lauren N., and Denton, Brian T.
- Description:
- This repository includes test instances of infinite-horizon Markov decision processes with multiple models of parameters (i.e., "Multi-model Markov decision processes"). We generated each test instance in the dataset using a Python script. The test instances can be read in using the provided C++ and Python script. See the README for details.
- Keyword:
- Markov decision processes, mixed-integer programming, stochastic programming, and dynamic programming
- Citation to related publication:
- Ahluwalia, Steimle, and Denton. "Policy-based branch-and-bound for infinite-horizon Multi-model Markov decision processes". 2020.
- Discipline:
- Engineering
-
- Creator:
- Whitaker, Steven T., Nataraj, Gopal, Nielsen, Jon-Fredrik, and Fessler, Jeffrey A.
- Description:
- File: P,jf06Sep2019,mese.7 The multi-echo spin echo (MESE) data was acquired using a 3D acquisition with an initial 90 degree excitation pulse followed by 32 refocusing (180 degree) pulses, resulting in 32 echoes with echo spacing of 10 ms. The repetition time of the sequence was 1200 ms. Each refocusing pulse was flanked by crusher gradients to impart 14 cycles of phase across the imaging volume. The initial excitation pulse had time-bandwidth product of 6, duration of 3 ms, and slab thickness of 0.9 cm, and each refocusing pulse had time-bandwidth product of 2, duration of 2 ms, and slab thickness of 2.1 cm. The scan took 36 min 11 s and covered a field of view (FOV) of 22 x 22 x 0.99 cm^3 with matrix size 200 x 200 x 9., File: P,jf06Sep2019,b1.7 The Bloch-Siegert (BS) scans were acquired using a 3D acquisition. The excitation pulse of these scans had time-bandwidth product of 8 and duration of 1 ms. The pair of scans used +/-4 kHz off-resonant Fermi pulses between excitation and readout. The BS scans took 2 min 40 s in total and covered a FOV of 22 x 22 x 0.99 cm^3 with matrix size 200 x 50 x 9., File: P,jf06Sep2019,mwf.7 The small-tip fast recovery (STFR) scans were acquired using a 3D acquisition. The first two and last two scans were pairs of spoiled gradient-recalled echo (SPGR) scans with echo time difference of 2.3 ms. (In the related paper, only the first set was used, i.e., only 11 of the 13 scans were used.) The remaining scans used scan parameters that were optimized to minimize the Cramer-Rao Lower Bound (CRLB) of estimates of myelin water fraction (MWF). The RF pulses had time-bandwidth product of 8 and duration of 1 ms. Each pair of SPGR scans took 58 s and the nine STFR scans took 3 min 36 s for a total scan time of 5 min 32 s (4 min 34 s if one pair of SPGR scans is ignored). The scans covered a field of view (FOV) of 22 x 22 x 0.99 cm^3 with matrix size 200 x 200 x 9., File: meseslice5.mat Contains the 32 echoes of the MESE image data for the middle slice of the imaging volume. Saved using Mathworks MATLAB R2019a., File: b1slice5.mat Contains the transmit field inhomogeneity map for the middle slice of the imaging volume., File: recon.jld Key "img" contains the 11 STFR images for the middle slice of the imaging volume. Key "b0map" contains a field map estimated from the two SPGR scans. Key "mask" contains a mask of the voxels for which to estimate MWF. Key "T1img" contains a T1-weighted image for anatomical reference., File: headmask.mat Contains a mask for visualizing just the brain (ignores the skull) for the middle slice of the imaging volume., File: rois.mat Contains masks for various regions of interest (ROIs), used for computing statistics. Keys "mtopleft", "mtopright", "mbottomleft", and "mbottomright" refer to the corresponding locations on the anatomical reference image (see related paper). Key "mic" refers to the internal capsules, and key "mgm" refers to a gray matter ROI., The raw data files (P-files) can be read into the Julia programming language using the Julia version of the Michigan Image Reconstruction Toolbox ( https://github.com/JeffFessler/MIRT.jl) or into MATLAB using TOPPE ( https://github.com/toppeMRI/toppe). The reconstructed slices used in the related paper are provided for convenience, and are stored in .mat files that can be loaded into Julia (using the package MAT.jl) or MATLAB, and a .jld file that can be loaded into Julia (using the package JLD.jl). The Julia code for processing the data to create MWF maps is hosted publicly on GitHub at https://github.com/StevenWhitaker/STFR-MWF., and Files: toppe-master.zip and MIRT.jl-master.zip are archived versions of the TOPPE and Michigan Image Reconstruction Toolbox code sets from GitHub as of 2/28/2020.
- Keyword:
- myelin, machine learning, kernel learning, magnetic resonance imaging, and scan design
- Citation to related publication:
- Whitaker, S. T., Nataraj, G., Nielsen, J.-F., & Fessler, J. A. (2020). Myelin water fraction estimation using small-tip fast recovery MRI. Magnetic Resonance in Medicine, 84(4), 1977–1990. https://doi.org/10.1002/mrm.28259
- Discipline:
- Health Sciences and Engineering